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Cao X, Xiong H, Fan Y, Xiong L. Comparing the Effects of Two Culture Methods to Determine the Total Heterotrophic Bacterial Colony Count in Hospital Purified Water. J Epidemiol Glob Health 2024; 14:184-192. [PMID: 38358615 PMCID: PMC11043230 DOI: 10.1007/s44197-023-00186-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2023] [Accepted: 12/26/2023] [Indexed: 02/16/2024] Open
Abstract
BACKGROUND Accurately detecting the quantity of microorganisms in hospital purified water is of significant importance for early identification of microbial contamination and reducing the occurrence of water-borne hospital infections. The choice of detection method is a prerequisite for ensuring accurate results. Traditional Plate Count Agar (PCA) belongs to a high-nutrient medium, and there may be limitations in terms of accuracy or sensitivity in detecting microorganisms in hospital purified water. On the other hand, Reasoner's 2A agar (R2A) has characteristics, such as low-nutrient levels, low cultivation temperature, and extended incubation time, providing advantages in promoting the growth of aquatic microorganisms. This study, through comparing the differences in total colony counts between two detection methods, aims to select the method more suitable for the growth of aquatic microorganisms, offering new practical insights for accurately detecting the total count of heterotrophic bacteria in hospital purified water. METHODS The most commonly used plate count agar (PCA) method, and the R2A agar culture were adopted to detect microorganisms and determine the total number of bacterial colonies in the water for oral diagnosis and treatment water and terminal rinse water for endoscopes in medical institutions. The two water samples were inoculated by pour plate and membrane filtration methods, respectively. Using statistical methods including Spearman and Pearson correlation, Wilcoxon signed-rank sum test, paired-Chi-square test, and linear regression, we analyze the differences and associations in the bacterial counts cultivated through two different methods. RESULTS In 142 specimens of the water, the median and interquartile range of the heterotrophic bacterial colony number under the R2A culture method and under the PCA culture method were 200 (Q1-Q3: 25-18,000) and 6 (Q1-Q3: 0-3700). The total number of heterotrophic bacteria colonies cultured in R2A medium for 7 days was more than that cultured in PCA medium for 2 days (P < 0.05). The linear regression results showed a relatively strong linear correlation between the number of colonies cultured by the R2A method and that cultured by the PCA method (R2 = 0.7264). The number of bacterial species detected on R2A agar medium is greater than that on PCA agar medium. CONCLUSION The R2A culture method can better reflect the actual number of heterotrophic bacterial colonies in hospital purified water. After logarithmic transformation, the number of colonies cultured by the two methods showed a linear correlation.
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Affiliation(s)
- Xiongjing Cao
- Department of Hospital Infection Management, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1277 Jiefang Ave, Wuhan, 430022, China
| | - Huangguo Xiong
- Department of Hospital Infection Management, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1277 Jiefang Ave, Wuhan, 430022, China
| | - Yunzhou Fan
- Department of Hospital Infection Management, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1277 Jiefang Ave, Wuhan, 430022, China
| | - Lijuan Xiong
- Department of Hospital Infection Management, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1277 Jiefang Ave, Wuhan, 430022, China.
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Akange ET, Aende AA, Rastegari H, Odeyemi OA, Kasan NA. Swinging between the beneficial and harmful microbial community in biofloc technology: A paradox. Heliyon 2024; 10:e25228. [PMID: 38352782 PMCID: PMC10861956 DOI: 10.1016/j.heliyon.2024.e25228] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2023] [Revised: 12/28/2023] [Accepted: 01/23/2024] [Indexed: 02/16/2024] Open
Abstract
Biofloc Technology (BFT) is proven to be the fulcrum of sustainable recirculating aquaculture system especially under zero water discharge condition. The efficiency of BFT system is reinforced by an unswerving microbial community in the system. Several researchers have made copious reports on the microorganisms in BFT and identified heterotrophic bacteria predominant in the microbial composition. A summary of these researches considers these microorganisms playing the role of chemo-photosynthetic autotrophs, organic detoxifiers, probiotic, decomposers/bioflocculants, bio-leachers and pathogens. Although these functional roles are well identified, the reports have failed to sufficiently illustrate the borderline at which these microbial communities fail to serve their beneficial roles in BFT system. This review paper firstly presents a snapshot of some indispensable water quality conditions and zootechnical variables aided by the microbial community in floc as well as the amphibolic process that synthesizes nutrient from the organic deposit in BFT. Furthermore, information on the microbial community in BFT is evaluated to have Bacillus sp., Lecane sp. and Pseudomonas sp. serving all-encompassing role in BFT while Vibrio sp. and Enterobacter sp. are pathogenic under unsuitable water quality conditions. Functional characterisation of the commonly reported microorganisms in BFT categorised 21.95 % as most critical, whose abundance indicates an efficient BFT.
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Affiliation(s)
- Edward Terhemen Akange
- Higher Institution Centre of Excellence (HICoE), Institute of Tropical Aquaculture and Fisheries (AKUATROP), Universiti Malaysia Terengganu, 21030 Kuala Nerus, Terengganu, Malaysia
- Department of Fisheries and Aquaculture, Joseph Sarwuan Tarka University (formerly, Federal University of Agriculture), Makurdi, P.M.B.2373, Benue State, Nigeria
| | - Athanasius Aondohemen Aende
- Department of Fisheries and Aquaculture, Joseph Sarwuan Tarka University (formerly, Federal University of Agriculture), Makurdi, P.M.B.2373, Benue State, Nigeria
| | - Hajar Rastegari
- Higher Institution Centre of Excellence (HICoE), Institute of Tropical Aquaculture and Fisheries (AKUATROP), Universiti Malaysia Terengganu, 21030 Kuala Nerus, Terengganu, Malaysia
| | - Olumide A. Odeyemi
- Office of Research Services, Research Division, University of Tasmania, Launceston, Australia
| | - Nor Azman Kasan
- Higher Institution Centre of Excellence (HICoE), Institute of Tropical Aquaculture and Fisheries (AKUATROP), Universiti Malaysia Terengganu, 21030 Kuala Nerus, Terengganu, Malaysia
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Song T, Xie W, Li Y, Li J, Zhang X, Dong W, Wang H. Rapid static feeding combined with Fe 2+ addition for improving the formation and stability of aerobic granular sludge in low-strength wastewater. Environ Res 2024; 242:117770. [PMID: 38029821 DOI: 10.1016/j.envres.2023.117770] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/21/2023] [Revised: 11/12/2023] [Accepted: 11/20/2023] [Indexed: 12/01/2023]
Abstract
Aerobic granular sludge (AGS) needs a long start-up time and always shows unstable performance when it is used to treat low-strength wastewater. In this study, a rapid static feeding combined with Fe2+ addition as a novel strategy was employed to improve the formation and stability of AGS in treating low-strength wastewater. Fe-AGS was formed within only 7 days and showed favorable pollutant removal capability and settling performance. The ammonia nitrogen (NH4+-N) and chemical oxygen demand (COD) concentration in the effluent were lower than 5 mg/L and 50 mg/L after day 23, respectively. The sludge volume index (SVI) and mixed liquid suspended solids (MLSS) was 37 mL/g and 2.15 g/L on day 50, respectively. Rapid static feeding can accelerate granules formation by promoting the growth of heterotrophic bacteria, but the granules are unstable due to filamentous bacteria overgrowth. Fe2+ addition can inhibit the growth of filamentous bacteria and promote the aggregation of functional bacteria (eg. Nitrosomonas, Nitrolancea, Paracoccus, Diaphorobacter) by enhancing the secretion of extracellular polymeric substances (EPS). This study provides a new way for AGS application in low-strength wastewater treatment.
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Affiliation(s)
- Tao Song
- School of Civil and Environmental Engineering, Harbin Institute of Technology, Shenzhen, Shenzhen, Guangdong, 518055, PR China; School of Ecology and Environment, Inner Mongolia University, Hohhot, 010021, PR China
| | - Wanying Xie
- College of Civil Engineering and Architecture, Xinjiang University, Urumqi, Xinjiang, 830017, PR China
| | - Yong Li
- School of Civil and Environmental Engineering, Harbin Institute of Technology, Shenzhen, Shenzhen, Guangdong, 518055, PR China
| | - Ji Li
- School of Civil and Environmental Engineering, Harbin Institute of Technology, Shenzhen, Shenzhen, Guangdong, 518055, PR China; Shenzhen Key Laboratory of Water Resource Utilization and Environmental Pollution Control, Shenzhen, 518055, PR China; State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, 150090, PR China
| | - Xiaolei Zhang
- School of Civil and Environmental Engineering, Harbin Institute of Technology, Shenzhen, Shenzhen, Guangdong, 518055, PR China.
| | - Wenyi Dong
- School of Civil and Environmental Engineering, Harbin Institute of Technology, Shenzhen, Shenzhen, Guangdong, 518055, PR China; Shenzhen Key Laboratory of Water Resource Utilization and Environmental Pollution Control, Shenzhen, 518055, PR China; State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, 150090, PR China
| | - Hongjie Wang
- School of Civil and Environmental Engineering, Harbin Institute of Technology, Shenzhen, Shenzhen, Guangdong, 518055, PR China; Shenzhen Key Laboratory of Water Resource Utilization and Environmental Pollution Control, Shenzhen, 518055, PR China; State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, 150090, PR China
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Mohan R, Pillai SS, Purushothaman A, Thomas LC, Padmakumar KB. Phylogenic diversity of bacteria associated with potentially toxic cyanobacteria Microcystis aeruginosa: a synthesis on its bloom dynamics. Folia Microbiol (Praha) 2023:10.1007/s12223-023-01108-1. [PMID: 37991690 DOI: 10.1007/s12223-023-01108-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2023] [Accepted: 11/10/2023] [Indexed: 11/23/2023]
Abstract
The occurrence of toxic bloom-forming cyanobacteria, Microcystis aeruginosa, has been frequently reported worldwide. These colony forming toxic cyanobacteria harbour a wide range of heterotrophic bacterial communities. The present study has attempted to understand the bloom dynamics of M. aeruginosa along with isolating their colony-associated culturable heterotrophic bacteria from two freshwater ponds in south India with a persisting cyanobacterial bloom. The monthly monitoring of these study areas revealed the conducive role of warm, stagnant waters with high nutrients in forming M. aeruginosa bloom. The peak values of temperature, nitrate, and phosphate at station 1 reached up to 30.5 °C, 4.48 mg/L, 1.64 mg/L, and at station 2, 31 °C, 3.45 mg/L, and 0.62 mg/L, respectively. Twenty-eight bacterial isolates belonging to Alphaproteobacteria, Betaproteobacteria, Gammaproteobacteria, Actinobacteria, and Firmicutes were obtained during the study. Among these 28 isolates, Firmicutes was dominant with the M. aeruginosa bloom from both the study areas.
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Affiliation(s)
- Renju Mohan
- Department of Marine Biology, Microbiology & Biochemistry, School of Marine Sciences, Cochin University of Science and Technology, Kochi-16, Kerala, India
| | - Sreya S Pillai
- Department of Marine Biology, Microbiology & Biochemistry, School of Marine Sciences, Cochin University of Science and Technology, Kochi-16, Kerala, India
| | - Aishwarya Purushothaman
- Department of Marine Biology, Microbiology & Biochemistry, School of Marine Sciences, Cochin University of Science and Technology, Kochi-16, Kerala, India
| | - Lathika Cicily Thomas
- Department of Marine Biology, Microbiology & Biochemistry, School of Marine Sciences, Cochin University of Science and Technology, Kochi-16, Kerala, India
| | - K B Padmakumar
- Department of Marine Biology, Microbiology & Biochemistry, School of Marine Sciences, Cochin University of Science and Technology, Kochi-16, Kerala, India.
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Sanghani AD, Patel RK, Dave SR, Tipre DR. Culturable heterotrophic bacterial diversity study from an Indian lignite mine habitat. Environ Monit Assess 2023; 195:649. [PMID: 37160469 DOI: 10.1007/s10661-023-11176-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/09/2022] [Accepted: 03/29/2023] [Indexed: 05/11/2023]
Abstract
Diversity lifts the productivity of any ecosystem as all the species have a vital role to play that is present within the ecosystem. The characterization is essential to delve into the ecological functions of microbial communities and discover the type of microorganisms present within the ecosystem. As microbial diversity in ecosystems responds to environmental disturbances, it functions as a marker to indicate the change in such ecosystems. Mine ecology differs significantly from other habitats due to the presence of acidic runoff. This paper provides insight into the diversity of cultivable bacteria isolated from lignite mines located in south Gujarat. A total of 67 heterotrophic isolates were successfully cultivated from the collected solid and water samples of the Rajpardi and Tadkeshwar Lignite mine sites. The isolates were characterized morphologically and biochemically, and intra- and extracellular enzyme synthesis were studied. Moreover, the relative density and frequency of cultivated isolates from the samples were calculated. The similarity and evenness of the heterotrophic isolated were studied by calculating diversity indices such as Shannon and Simpson. Alpha diversity was calculated in PAST software to analyse the similarity between the selected two mine sites. This research also explored the relationship between the variance in heterotrophic microbial diversity and substrate utilization richness of the studied lignite mines of Gujarat.
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Affiliation(s)
- Anjana D Sanghani
- Department of Microbiology and Biotechnology, School of Sciences, Gujarat University, Ahmedabad, 380009, India
- Bioinformatics and Supercomputer Lab, Department of Biosciences, Veer Narmad South Gujarat University, Surat, 395007, India
| | - Rajesh K Patel
- Bioinformatics and Supercomputer Lab, Department of Biosciences, Veer Narmad South Gujarat University, Surat, 395007, India
| | - Shailesh R Dave
- Xavier's Research Foundation, Loyola Centre for R & D, St. Xavier College Campus, Navarangpura, Ahmedabad, 380009, India
| | - Devayani R Tipre
- Department of Microbiology and Biotechnology, School of Sciences, Gujarat University, Ahmedabad, 380009, India.
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Bhatawadekar VC, Damare SR, Garg A. Folin-Ciocalteu assay as a rapid colourimetric screening method for evaluating PAH degradation abilities of heterotrophic bacteria. 3 Biotech 2023; 13:144. [PMID: 37124990 PMCID: PMC10140204 DOI: 10.1007/s13205-023-03549-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2022] [Accepted: 03/28/2023] [Indexed: 05/02/2023] Open
Abstract
Bioremediation using microbes is an eco-friendly approach being explored for reclaiming PAH-contaminated areas. However, isolation and screening of potential bacteria to degrade PAHs are very laborious and cumbersome. To alleviate this issue, we describe a rapid method for screening the bacterial cultures for their ability to degrade PAHs using Folin-Ciocalteu (FC) assay. Six hundred bacterial isolates were tested for their ability to degrade PAH using FC assay. The cultures capable of degrading PAH show blue colouration, resulting from the reaction of FC reagent with phenolic intermediates generated during PAH degradation. Out of the 600 cultures screened, 64 showed an ability to degrade PAH. This study provides a very easy, rapid, less laborious, and sensitive method to screen a large number of bacterial cultures for their ability to degrade PAH. Supplementary Information The online version contains supplementary material available at 10.1007/s13205-023-03549-4.
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Affiliation(s)
- Vasudha C. Bhatawadekar
- Biological Oceanography Division, CSIR-National Institute of Oceanography, Dona Paula, Goa 403004 India
- Department of Microbiology, Goa University, Taleigao Plateau, Goa India
| | - Samir R. Damare
- Biological Oceanography Division, CSIR-National Institute of Oceanography, Dona Paula, Goa 403004 India
| | - Anita Garg
- Analytical Services Division, CSIR-National Institute of Oceanography, Dona Paula, Goa 403004 India
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Ya T, Huang Y, Wang K, Wang J, Liu J, Hai R, Zhang T, Wang X. Functional stability correlates with dynamic microbial networks in anammox process. Bioresour Technol 2023; 370:128557. [PMID: 36587773 DOI: 10.1016/j.biortech.2022.128557] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/14/2022] [Revised: 12/26/2022] [Accepted: 12/27/2022] [Indexed: 06/17/2023]
Abstract
Understanding the relationship between dynamic microbial networks and functional stability is critical for the stable operation of anammox systems. Here, by operating an anammox reactor under constant condition over 250 days, it was found that the relative abundance of Planctomycetota gradually decreased while Chloroflexi and Proteobacteria increased, with stochasticity predominating the bacterial assembly as the reactor operation. Network analysis revealed a successional dynamic pattern of microbial interaction despite stable performance. The variation of subnetworks indicated Chloroflexi and Proteobacteria alternately played important role in anammox microbial network, and the negative relationship between anammox bacteria and heterotrophs could achieve a balance to keep functional stability under long-term operation. Furthermore, the identified keystone species mainly belonged to heterotrophs that were critical in maintaining network structure and system function. The results of this study revealed clear changing patterns of microbial community and network succession, which could provide valuable reference for other stably operated bioreactors.
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Affiliation(s)
- Tao Ya
- Beijing Engineering Research Center of Environmental Material for Water Purification, College of Chemical Engineering, Beijing University of Chemical Technology, Beijing 100029, China
| | - Yan Huang
- Beijing Engineering Research Center of Environmental Material for Water Purification, College of Chemical Engineering, Beijing University of Chemical Technology, Beijing 100029, China
| | - Kening Wang
- Beijing Engineering Research Center of Environmental Material for Water Purification, College of Chemical Engineering, Beijing University of Chemical Technology, Beijing 100029, China
| | - Jiaao Wang
- Beijing Engineering Research Center of Environmental Material for Water Purification, College of Chemical Engineering, Beijing University of Chemical Technology, Beijing 100029, China
| | - Junyu Liu
- Beijing Engineering Research Center of Environmental Material for Water Purification, College of Chemical Engineering, Beijing University of Chemical Technology, Beijing 100029, China
| | - Reti Hai
- Beijing Engineering Research Center of Environmental Material for Water Purification, College of Chemical Engineering, Beijing University of Chemical Technology, Beijing 100029, China
| | - Tingting Zhang
- Beijing Engineering Research Center of Environmental Material for Water Purification, College of Chemical Engineering, Beijing University of Chemical Technology, Beijing 100029, China
| | - Xiaohui Wang
- Beijing Engineering Research Center of Environmental Material for Water Purification, College of Chemical Engineering, Beijing University of Chemical Technology, Beijing 100029, China.
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Ashok A, Agusti S. Contrasting sensitivity among oligotrophic marine microbial communities to priority PAHs. Chemosphere 2022; 309:136490. [PMID: 36210574 DOI: 10.1016/j.chemosphere.2022.136490] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/20/2022] [Revised: 09/14/2022] [Accepted: 09/15/2022] [Indexed: 06/16/2023]
Abstract
Oligotrophic areas represent a large proportion of the oceans, wherein microbial food webs largely determine carbon flux dynamics and biogeochemical cycles. However, little is known regarding the sensitivity of microbial planktonic communities to pollutants in such areas. Organic pollutants such as polycyclic aromatic hydrocarbons (PAH/s) are toxic oil derivatives that occur as complex mixtures and reach marine environments through different sources. Therefore, our study analyzed the PAH tolerance of natural photosynthetic and heterotrophic bacteria and eukaryotes from the oligotrophic Red Sea, which is uniquely susceptible to high oil contamination. Natural communities sampled from the surface layer were exposed to a concentration gradient of a mixture of 16 priority PAHs at in situ conditions for 48 h. The populations of the dominant picocyanobacteria Synechococcus sp., picophytoeukaryotes, and low nucleic acid (LNA) bacteria decreased upon exposure to PAHs in a strong dose-dependent manner. Chlorophyll-a, which was measured as an indicator of the total autotrophic community response, also decreased substantially. High nucleic acid (HNA) bacteria, however, exhibited lower growth inhibition (<50%). The lethal concentration (LC10) thresholds to the 16-PAH mixture demonstrated contrasting sensitivities among the microbial communities studied increasing from picoeukaryotes (5.98 ± 2.08 μg L-1) < chlorophyll-a (19.51 ± 8.11 μg L-1) < LNA bacteria (23.63 ± 10.64 μg L-1) < Synechococcus sp. (26.77 ± 13.34 μg L-1) < HNA bacteria (97.13 ± 17.28 μg L-1). The sensitivity of Red Sea Synechococcus and picophytoeukaryotes to the 16-PAH mixture was between 2 and 6.5 times higher compared to single PAH compounds tested previously. However, some populations of HNA bacteria and Synechococcus sp., were highly tolerant, suggesting an adaptation to chronic pollution. Concerningly, the LC10 toxicity thresholds approached the ambient PAH concentrations in the Red Sea, suggesting that environmental oil pollution actively shapes the microbial community structures in the region.
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Affiliation(s)
- Ananya Ashok
- Red Sea Research Center, King Abdullah University of Science and Technology, Saudi Arabia.
| | - Susana Agusti
- Red Sea Research Center, King Abdullah University of Science and Technology, Saudi Arabia
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Ya T, Liu J, Zhang M, Wang Y, Huang Y, Hai R, Zhang T, Wang X. Metagenomic insights into the symbiotic relationship in anammox consortia at reduced temperature. Water Res 2022; 225:119184. [PMID: 36206682 DOI: 10.1016/j.watres.2022.119184] [Citation(s) in RCA: 32] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/09/2022] [Revised: 09/27/2022] [Accepted: 09/29/2022] [Indexed: 06/16/2023]
Abstract
Anammox as a promising biological nitrogen removal technology has attracted much attention. However, cold temperature would limit its wide application and little is known about the microbial interactions between anammox bacteria (AnAOB) and heterotrophic bacteria at cold temperature. Here, we observed reduced temperature (25-15 °C) promoted the secretion of EPS and thus stimulated bigger size of granular sludge in a laboratory-scale anammox reactor. We further combined co-occurrence network analysis and genome-centered metagenomics to explore the potential interactions between AnAOB and heterotrophic bacteria. Network analysis suggested 22 out of 25 positively related species were reported as definite heterotrophic bacteria in subnetwork of AnAOB. Genome-centered metagenomics analysis yielded 23 metagenomic assembly genomes (MAGs), and we found that Acidobacteriota-affiliated bacteria could biosynthesize most polysaccharides (PS) precursors and contain the most glycosyltransferases and transporters to facilitate exopolysaccharides biosynthesis, together with partial PS precursors produced by AnAOB. AMX1 as the only anammox genome could synthesize most amino acids and cross feed with some heterotrophs to affect the extracellular protein function. Additionally, Bacteroidota, Planctomycetota, Chloroflexota, and Proteobacteria could contribute folate and molybdopterin cofactor for AMX1 to benefit their activity and growth. Superphylum Patescibacteria could survive by cross-feeding with AnAOB and heterotrophic organisms about organic compounds (Glyceraldehyde-3P and lactate). These cross-feedings maintained the stability of anammox reactor performance and emphasize the importance of heterotrophs in anammox system at reduced temperature.
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Affiliation(s)
- Tao Ya
- Beijing Engineering Research Center of Environmental Material for Water Purification, College of Chemical Engineering, Beijing University of Chemical Technology, Beijing 100029, China
| | - Junyu Liu
- Beijing Engineering Research Center of Environmental Material for Water Purification, College of Chemical Engineering, Beijing University of Chemical Technology, Beijing 100029, China
| | - Minglu Zhang
- State Environmental Protection Key Laboratory of Food Chain Pollution Control, Beijing Technology and Business University, Beijing 100048, China
| | - Yulin Wang
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao 266000, PR China
| | - Yan Huang
- Beijing Engineering Research Center of Environmental Material for Water Purification, College of Chemical Engineering, Beijing University of Chemical Technology, Beijing 100029, China
| | - Reti Hai
- Beijing Engineering Research Center of Environmental Material for Water Purification, College of Chemical Engineering, Beijing University of Chemical Technology, Beijing 100029, China
| | - Tingting Zhang
- Beijing Engineering Research Center of Environmental Material for Water Purification, College of Chemical Engineering, Beijing University of Chemical Technology, Beijing 100029, China.
| | - Xiaohui Wang
- Beijing Engineering Research Center of Environmental Material for Water Purification, College of Chemical Engineering, Beijing University of Chemical Technology, Beijing 100029, China.
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Chuah LF, Chew KW, Bokhari A, Mubashir M, Show PL. Biodegradation of crude oil in seawater by using a consortium of symbiotic bacteria. Environ Res 2022; 213:113721. [PMID: 35738420 DOI: 10.1016/j.envres.2022.113721] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/20/2022] [Revised: 05/06/2022] [Accepted: 06/15/2022] [Indexed: 06/15/2023]
Abstract
This work presents the enhancement of oil biodegradation in seawater using a mixture of oil and microorganisms. Retardation of crude oil biodegradation in seawater is hypothetically due to the inhibiting of metabolites produced by the oil bacterium which inhibit its enzymes. For this purpose, the bacteria consortium consisting of an active oil-oxidizing bacterium (AR3-Pseudomonas pseudoalcaligenes) and two oil-resistant and active heterotrophic bacteria (OG1 and OG2-Erythrobacter citreus) were formed. The heterotrophic bacteria, OG1 and OG2 were able to remove metabolites produced during oil degradation. It was found that AR3 was retarded by metabolites, while OG1 and OG2 were able to grow in the metabolites. OG1 and OG2 were applied together to enhance growth and removal of the metabolites. About 59.9% of crude oil degradation was degraded by AR3 pure culture, while 68.6% was degraded by the bacteria consortium. About 31.4% of the crude oil was found to remain in seawater due to the presence of asphaltenes and resin hydrocarbons. The bacteria consortium was able to degrade 84.1% of total hydrocarbons while 67.0% was degraded by AR3. A total of 99.8% of the aliphatic content and 38.4% of the total aromatic hydrocarbons were degraded by the bacteria consortium, while a lower 79.4% of total aliphatic and 31.0% of total aromatic were degraded by AR3 under the same experimental conditions. The results which were obtained from this study support the hypothesis that the retardation of oil degradation by AR3 is due to the inhibition of metabolites on the growth.
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Affiliation(s)
- Lai Fatt Chuah
- Faculty of Maritime Studies, Universiti Malaysia Terengganu, Terengganu, Malaysia.
| | - Kit Wayne Chew
- School of Energy and Chemical Engineering, Xiamen University Malaysia, 43900, Sepang, Selangor, Malaysia; College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, 361005, Fujian, China
| | - Awais Bokhari
- Chemical Engineering Department, COMSATS Institute of Information Technology, Lahore, Pakistan
| | - Muhammad Mubashir
- Department of Petroleum Engineering, School of Engineering, Asia Pacific University of Technology and Innovation, 57000, Kuala Lumpur, Malaysia
| | - Pau Loke Show
- Department of Chemical and Environmental Engineering, Faculty of Science and Engineering, University of Nottingham Malaysia, 43500, Semenyih, Selangor, Malaysia.
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Kalkan S. Multimodal analysis of south-eastern Black Sea sediment bacterial population diversity. Mar Pollut Bull 2022; 183:114063. [PMID: 36057154 DOI: 10.1016/j.marpolbul.2022.114063] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/17/2022] [Revised: 07/15/2022] [Accepted: 08/18/2022] [Indexed: 06/15/2023]
Abstract
This study focused on marine sediments from the Black Sea, mainly due to bacterial diversity-induced public health / biotechnology application value. Sediment samples were gathered from 14 locations at differing depths across Turkish shores on a seasonal basis over 10 months, with bacterial identifications performed through using multimodal analytical platforms. Overall, 26 differing, predominantly Gram-positive (57.5 %) bacterial species were identified for this region, including Bacillaceae (50.0 %) and Pseudomonadaceae (15.0 %). The most dominant classes were identified as Bacilli (52.5 %) and Gammaproteobacteria (40.0 %). Ten isolates (25 %) to the species level and thirty-six isolates (90 %) to the genus level were identified using VITEK® MS and Bruker Microflex® LT/SH, in comparison to 16S rRNA sequencing results. Identified species - particularly, novel reported species - can contribute to the knowledge of microbial life dwelling upon sediments of the south-eastern regions of the Black Sea.
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Affiliation(s)
- Samet Kalkan
- Recep Tayyip Erdogan University, Faculty of Fisheries, Ataturk Street Fener District, 53100 Merkez, Rize, Turkey.
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12
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Furukawa T, Mekata T, Amarasiri M, Sei K. Concentration and reduction efficiency of vancomycin-resistant heterotrophic bacteria and vanA and vanB genes in each wastewater treatment unit processes. J Glob Antimicrob Resist 2022; 30:340-347. [PMID: 35830952 DOI: 10.1016/j.jgar.2022.07.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2022] [Revised: 06/20/2022] [Accepted: 07/05/2022] [Indexed: 10/17/2022] Open
Abstract
OBJECTIVES This study elucidated the distribution and fate of vancomycin (VCM)-resistant heterotrophic bacteria (HTB) and resistance genes, vanA and vanB, during each treatment unit process of a wastewater treatment plant (WWTP). METHODS Several bacterial counts as well as copy numbers of vanA and vanB genes were determined in each wastewater and sludge. In addition, HTB strains isolated from wastewater and sludge were analyzed for VCM susceptibility. Then, the fate and reduction ratios of each bacterial counts, copy numbers of vanA and vanB genes, and the existence ratio of VCM-resistant HTB strains in the wastewater treatment unit process were evaluated. RESULTS VCM-resistant HTB were detected in all wastewater and sludge samples, and their existence ratio decreased along the treatment (92.9% in influent wastewater to 39.4% in chlorinated water). Notably, most of the HTB isolated from the influent wastewater were resistant to 8.0 µg/mL of VCM, strongly suggesting that a significant amount of ARB is flowing into the WWTP from urban areas through the sewerage system. The vanA and vanB genes were also detected in all wastewater and sludge, with high copy numbers (102-104 copies/mL) even in chlorinated water samples. CONCLUSIONS The results revealed that residual VCM-resistant HTB, and resistance genes, which could not be completely removed, were ubiquitously released into the aquatic environment. Furthermore, a high existence ratio of VCM-resistant HTB and high copy numbers of resistance genes were also detected in the sludge, indicating that they are constantly circulating in the wastewater treatment system via the returned sludge.
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Affiliation(s)
- Takashi Furukawa
- Laboratory of Environmental Hygiene, Department of Health Science, School of Allied Health Sciences, Kitasato University, 1-15-1, Kitasato, Sagamihara-Minami, 252-0373, Japan.
| | - Tohru Mekata
- Department of Veterinary Medicine, Faculty of Veterinary Medicine, Okayama University of Science, 1-3 Ikoinooka, Imabari, Ehime 794-8555, Japan.
| | - Mohan Amarasiri
- Laboratory of Environmental Hygiene, Department of Health Science, School of Allied Health Sciences, Kitasato University, 1-15-1, Kitasato, Sagamihara-Minami, 252-0373, Japan.
| | - Kazunari Sei
- Laboratory of Environmental Hygiene, Department of Health Science, School of Allied Health Sciences, Kitasato University, 1-15-1, Kitasato, Sagamihara-Minami, 252-0373, Japan.
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13
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Kalkan S. Heavy metal resistance of marine bacteria on the sediments of the Black Sea. Mar Pollut Bull 2022; 179:113652. [PMID: 35500375 DOI: 10.1016/j.marpolbul.2022.113652] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/29/2021] [Revised: 03/22/2022] [Accepted: 04/05/2022] [Indexed: 06/14/2023]
Abstract
The Black Sea is unfortunately globally established as a highly polluted sea, with contaminants from various sources polluting its marine sediments. This study aimed at analyzing heavy metal resistance levels by heterotrophic bacteria colonizing marine sediments across Black Sea shores within Turkey. Twenty-nine bacterial samples from marine sediments were investigated through exposure to sixteen heavy metal salts using the microdilution method. The minimum inhibitory concentration values for bacterial colonies within such marine sediment samples ranged from <0.97 mM/L to >1000 mM/L. Trough and peak minimum inhibitory concentration values were determined at <0.17 mg/mL and > 331 mg/mL. Peak tolerated and peak toxic heavy metals were identified as iron and cadmium, respectively. Resistance ratios were also obtained in this study. Bacillus wiedmannii was identified as the most resistant bacterial population when exposed to heavy metal salts. This study shows occurrence of heavy metal resistant bacteria within Black Sea sediments.
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Affiliation(s)
- Samet Kalkan
- Recep Tayyip Erdogan University, Faculty of Fisheries, Ataturk Street Fener District, 53100 Merkez, Rize, Turkey.
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14
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Su Y, Gan Y, Shi L, Li K, Liu Z. Does ancient permafrost-derived organic carbon affect lake zooplankton growth? An experimental study on Daphnia magna. Environ Pollut 2022; 300:118968. [PMID: 35134428 DOI: 10.1016/j.envpol.2022.118968] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2021] [Revised: 01/20/2022] [Accepted: 02/04/2022] [Indexed: 06/14/2023]
Abstract
The popular paradigm in trophic dynamic theory is that contemporary autochthonous organic matter (e.g., phytoplankton) sustains consumer growth, whereas aged allochthonous organic matter is conceptually considered recalcitrant resources that may only be used to support consumer respiration but suppress consumer growth. This resource-age paradigm has been challenged by a growing body of recent evidence that ancient (radiocarbon depleted) organic carbon (OC) released from glaciers and permafrost can be incorporated by consumers in aquatic systems. However, little information is available regarding the food quality of ancient terrestrial OC and how it impacts the growth of consumers in lakes. Here, ancient dissolved organic carbon (DOC) was extracted from frozen soils in an alpine lake catchment. The contents of polyunsaturated fatty acids (PUFAs) in soil DOC increased significantly after bioconversion by heterotrophic bacteria. The utilization of soil DOC by heterotrophic bacteria also increased the total phosphorus concentration in the systems. Gammaproteobacteria and Betaproteobacteria showed a strong negative correlation with the percentage contents of fluorescent components, including humic-like and tyrosine-like components. Daphnia magna were fed Auxenochlorella vulgaris and ancient DOC plus heterotrophic bacteria. The contents of PUFAs and the growth of zooplankton were influenced by the pre-conversion time of ancient DOC by bacteria. When ancient DOC was pre-converted by bacteria for 27 days, D. magna fed on the mixed diets showed the highest body length (3.40 mm) and intrinsic rate of increase in population (0.49 d-1). Our findings provide direct evidence that ancient terrestrial OC can be an important subsidy for lake secondary production, which have important implications for food webs in high-altitude and polar lakes.
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Affiliation(s)
- Yaling Su
- State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, 73 East Beijing Road, Nanjing, 210008, China.
| | - Yingxin Gan
- State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, 73 East Beijing Road, Nanjing, 210008, China
| | - Limei Shi
- State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, 73 East Beijing Road, Nanjing, 210008, China
| | - Kuanyi Li
- State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, 73 East Beijing Road, Nanjing, 210008, China
| | - Zhengwen Liu
- State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, 73 East Beijing Road, Nanjing, 210008, China; Sino-Danish Center for Education and Research (SDC), University of Chinese Academy of Sciences, Beijing, China
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15
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Wang S, Yu H, Su Q, Zuo J. Exploring the role of heterotrophs in partial nitritation-anammox process treating thermal hydrolysis process - anaerobic digestion reject water. Bioresour Technol 2021; 341:125762. [PMID: 34450441 DOI: 10.1016/j.biortech.2021.125762] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/14/2021] [Revised: 08/07/2021] [Accepted: 08/10/2021] [Indexed: 06/13/2023]
Abstract
Heterotrophic bacteria (HB) are generally prevalent in anammox-based processes, but their functional and ecological roles in partial nitritation-anammox (PN/A) process treating high-organics wastewater remained unclear. This study aimed to elucidate HB activities and microbial interactions in a one-stage PN/A treating thermal hydrolysis process (THP) - anaerobic digestion (AD) reject water. The PN/A reactor achieved a satisfactory nitrogen removal rate of 0.58 ± 0.06 g N/(L·d), and around 12% of COD in the THP-AD reject water was removed. N2O emission factors of the PN/A reactor were 1.15% ± 0.18% treating synthetic wastewater, and 0.95% ± 0.06% treating reject water. A balanced symbiotic relationship was maintained between HB and functional groups (i.e., anammox bacteria and aerobic-ammonia-oxidizing bacteria) over the reactor operation. The relative abundances of Anaerolineae spp. clearly increased, while Denitratisoma, capable of denitrification, slightly decreased when treating THP-AD reject water. The preference for electron donors of heterotrophs explained discrepant growth trends.
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Affiliation(s)
- Sike Wang
- Department of Material and Environmental Engineering, Shenzhen Polytechnic, Shenzhen 518055, China; State Key Joint Laboratory of Environmental Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China
| | - Heng Yu
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China; College of Chemistry and Chemical Engineering, Xi'an Shiyou University, Xi'an, Shaanxi Province 710065, China
| | - Qingxian Su
- Department of Environmental Engineering, Technical University of Denmark, Kgs., Lyngby 2800, Denmark
| | - Jiane Zuo
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China; Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, China.
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16
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Golzar-Ahmadi M, Mousavi SM. Extraction of valuable metals from discarded AMOLED displays in smartphones using Bacillus foraminis as an alkali-tolerant strain. Waste Manag 2021; 131:226-236. [PMID: 34171827 DOI: 10.1016/j.wasman.2021.06.006] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/02/2021] [Revised: 06/09/2021] [Accepted: 06/13/2021] [Indexed: 06/13/2023]
Abstract
With the alarming rate of e-waste generation, resource recovery from secondary metal sources is essential for sustainable resource utilization and to prevent the release of potentially toxic elements into the environment. In the current study, the first-time extraction of Ag, Mo, and Cu from active-matrix organic light-emitting diode (AMOLED) screens of discarded smartphones have been achieved using organic acids produced by Bacillus foraminis cultured on a modified Horikoshi medium. The influences of initial pH, inoculation size, and pulp density on the bioleaching process were evaluated over six-day experiment. Maximum extraction of Ag, Mo, and Cu (100, 56.8, and 41.4%) at optimal values of three investigated factors was obtained over a 12-day bioleaching experiment. A diverse assemblage of organic acid was produced in the optimized bioleaching condition, including tartaric (12.1 mM), formic (49.8 mM), acetic (21.5 mM), lactic (78.5 mM), citric (2.7 mM), and propionic (69.6 mM) acid. The contact angle analysis highlighted more hydrophobicity of powder after the bioleaching. FTIR and CHNO data also confirmed the role of bioleaching in the powder wettability alteration. The sequential extraction method revealed high mobility of In, Fe, Co, Cu, Cr, and Mo and low mobility of Ag. The results exhibited high tolerance of alkali-tolerant bacteria to potentially toxic elements and its superior performance in the bioleaching of discarded mobile screens at high pulp density.
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Affiliation(s)
- Mehdi Golzar-Ahmadi
- Biotechnology Group, Chemical Engineering Department, Tarbiat Modares University, Tehran, Iran
| | - Seyyed Mohammad Mousavi
- Biotechnology Group, Chemical Engineering Department, Tarbiat Modares University, Tehran, Iran; Modares Environmental Research Institute, Tarbiat Modares University, Tehran, Iran.
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17
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Xiang T, Liang H, Wang P, Gao D. Insights into two stable mainstream deammonification process and different microbial community dynamics at ambient temperature. Bioresour Technol 2021; 331:125058. [PMID: 33812136 DOI: 10.1016/j.biortech.2021.125058] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/27/2021] [Revised: 03/20/2021] [Accepted: 03/21/2021] [Indexed: 06/12/2023]
Abstract
How to achieve stable mainstream deammonification is still a huge challenge. In this work, satisfactory nitrogen removal were achieved in a deammonification granular sludge reactor (R1, 0.42 ± 0.03 kg N / (m3·d)) and a mixed flocculent with granular sludge reactor (R2, 0.39 ± 0.04 kg N / (m3·d)) at ambient temperature (21-28 ℃) . The good adaptability of anammox bacteria (Candidatus Jettenia) to ambient temperature ensured its efficient activity (0.84-1.54 mg N/(g VSS·h)). The overexpression ammonia monooxygenase gene abundances in ammonia oxidizing bacteria (Nitrosomonas) was also predicted. The inhibition of hydrazine and the competition of denitrifying bacteria (Denitratisoma) to nitrite nitrogen, leading to a low Nitrospira relative abundances (0.2%-2.1%) . It was also found that R1 was more resistant to the unfavorable condition. For R2, higher Denitratisoma abundances (9.2%-18.5%) and predicted metabolic pathway abundances related to carbon metabolism were observed.
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Affiliation(s)
- Tao Xiang
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Hong Liang
- Center for Urban Environmental Remediation, Beijing University of Civil Engineering and Architecture, Beijing 100044, China
| | - Peng Wang
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Dawen Gao
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, China; Center for Urban Environmental Remediation, Beijing University of Civil Engineering and Architecture, Beijing 100044, China.
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18
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Donohue MJ. Quantification of Legionella pneumophila by qPCR and culture in tap water with different concentrations of residual disinfectants and heterotrophic bacteria. Sci Total Environ 2021; 774:145142. [PMID: 33610980 PMCID: PMC8358786 DOI: 10.1016/j.scitotenv.2021.145142] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/14/2020] [Revised: 01/07/2021] [Accepted: 01/08/2021] [Indexed: 05/21/2023]
Abstract
Legionellosis prevalence is increasing in the United States. This disease is caused primarily by the bacterium Legionella pneumophila found in water and transmitted by aerosol inhalation. This pathogen has a slow growth rate and can "hide" in amoeba, making it difficult to monitor by the traditional culture method on selective media. Tap water samples (n = 358) collected across the United States were tested for L. pneumophila by both culture and quantitative Polymerase Chain Reaction (qPCR). The presence of other bacteria was quantified by heterotrophic plate counts (HPC). Residual disinfectant concentrations (free chlorine or monochloramine) were measured in all samples. Legionella pneumophila had the highest prevalence and concentration in the chlorinated water samples that had a free‑chlorine value of less than 0.2 mg Cl2/L. In total, 24% (87/358) of the samples were positive for L. pneumophila either by qPCR or 3% (11/358) were positive by culture. In chloramine-treated samples, L. pneumophila was detected by qPCR in 21% (31/148) and 1% (2/148) by culture, despite a high monochloramine residual >1 mg Cl2/L. Despite the presence of a high disinfectant residual (>1 mg Cl2/L), HPC counts were substantial. This study indicates that both culture and qPCR methods have limitations when predicting a potential risk for disease associated with L. pneumophila in tap water. Measuring disinfectant residuals and quantifying HPC in water samples may be useful adjunct parameters for reducing Legionellosis' risk from public water supplies at high-risk locations.
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Affiliation(s)
- Maura J Donohue
- United States Environmental Protection Agency, Office Research and Development, Center for Environmental Solutions and Emergency Response, Cincinnati, OH 45268, United States of America.
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19
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Liu J, Sun J, Lu C, Yue P, Kang X, Liu X. Bioaerosol emissions of pilot-scale low-pH and neutral-pH biofilters treating odors from landfill leachate: Characteristics and impact factors. Waste Manag 2021; 128:64-72. [PMID: 33965674 DOI: 10.1016/j.wasman.2021.04.040] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/11/2020] [Revised: 04/11/2021] [Accepted: 04/15/2021] [Indexed: 06/12/2023]
Abstract
Large amounts of bioaerosols are generated during the treatment of landfill leachate, which poses potential threat to public health safety. In this study, the concentrations, particle size distribution, and microbial community of bioaerosols emitted from the low-pH biofilter (LPB) and neutral-pH biofilter (NPB) used to treat the odors from landfill leachate, as well as the effect of the inlet flow rate (IFR) and water-containing rate (WCR) were investigated. The results showed that the removal efficiency of the LPB for heterotrophic bacteria and the NPB for fungi were higher when the IFR was higher. The outlet concentrations (OCs) of heterotrophic bacteria, neutral sulfur bacteria, ammonia-oxidizing bacteria, nitrite-oxidizing bacteria, NO2-, and NO3- were negatively correlated with the IFR in the LPB, whereas those of fungi and acidophilic sulfur bacteria were positively correlated with the IFR. Inverse correlation between the OCs and IFR was exhibited in the NPB. The proportions of dominant microorganisms with large particle size (> 3.3 μm) reduced significantly after both the LPB and NPB, which was aggravated under higher WCR. The analysis of microbial community illustrated that the dominant heterotrophic bacteria were different, while the dominant fungi were similar in the bioaerosols between the LPB and NPB, respectively. Due to the different emission characteristics, bioaerosols in the LPB and NPB outlet should be distinguished and taken seriously.
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Affiliation(s)
- Jianwei Liu
- Beijing Engineering Research Center of Sustainable Urban Sewage System Construction and Risk Control, Beijing University of Civil Engineering and Architecture, Beijing 100044, China; Key Laboratory of Urban Stormwater System and Water Environment, Ministry of Education, Beijing University of Civil Engineering and Architecture, Beijing 100044, China
| | - Jianbin Sun
- Beijing Engineering Research Center of Sustainable Urban Sewage System Construction and Risk Control, Beijing University of Civil Engineering and Architecture, Beijing 100044, China; Key Laboratory of Urban Stormwater System and Water Environment, Ministry of Education, Beijing University of Civil Engineering and Architecture, Beijing 100044, China
| | - Chen Lu
- Beijing Engineering Research Center of Sustainable Urban Sewage System Construction and Risk Control, Beijing University of Civil Engineering and Architecture, Beijing 100044, China; Key Laboratory of Urban Stormwater System and Water Environment, Ministry of Education, Beijing University of Civil Engineering and Architecture, Beijing 100044, China
| | - Peng Yue
- Beijing Engineering Research Center of Sustainable Urban Sewage System Construction and Risk Control, Beijing University of Civil Engineering and Architecture, Beijing 100044, China; Key Laboratory of Urban Stormwater System and Water Environment, Ministry of Education, Beijing University of Civil Engineering and Architecture, Beijing 100044, China
| | - Xinyue Kang
- Beijing Engineering Research Center of Sustainable Urban Sewage System Construction and Risk Control, Beijing University of Civil Engineering and Architecture, Beijing 100044, China; Key Laboratory of Urban Stormwater System and Water Environment, Ministry of Education, Beijing University of Civil Engineering and Architecture, Beijing 100044, China
| | - Xueli Liu
- Beijing Engineering Research Center of Sustainable Urban Sewage System Construction and Risk Control, Beijing University of Civil Engineering and Architecture, Beijing 100044, China; Key Laboratory of Urban Stormwater System and Water Environment, Ministry of Education, Beijing University of Civil Engineering and Architecture, Beijing 100044, China
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20
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Wan W, Grossart HP, He D, Yuan W, Yang Y. Stronger environmental adaptation of rare rather than abundant bacterioplankton in response to dredging in eutrophic Lake Nanhu (Wuhan, China). Water Res 2021; 190:116751. [PMID: 33348071 DOI: 10.1016/j.watres.2020.116751] [Citation(s) in RCA: 52] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2020] [Revised: 12/08/2020] [Accepted: 12/13/2020] [Indexed: 06/12/2023]
Abstract
Deciphering responses of rare versus abundant bacterioplankton to environmental change, crucial for understanding and mitigating of cyanobacterial blooms, is an important but poorly investigated subject. Using MiSeq sequencing, we investigated the taxonomic and phylogenetic diversity of rare and abundant bacterioplankton in eutrophic Lake Nanhu before and after dredging. We estimated environmental breadths and phylogenetic signals of ecological preferences of rare and abundant bacterioplankton, and investigated community function and bacterioplankton assembly processes. Both taxonomic and phylogenic distances of rare and abundant bacterioplankton communities were significantly positively correlated with the dissimilarity of environmental factors. Threshold indicator taxa analysis and Blomberg's K statistic indicated that rare taxa held broader environmental thresholds and stronger phylogenetic signals for ecological traits than abundant taxa. Environmental adaptations of both rare and abundant taxa exhibited distinct changes after dredging. Higher functional redundancy occurred in the abundant compared to the rare bacterioplankton, with functions of rare bacterioplankton decreasing and for the abundant ones increasing after dredging. The null model revealed that dispersal limitation belonging to stochastic processes determined the abundant bacterioplankton community assembly, whereas variable selection belonging to deterministic processes drove the rare one. Rare bacterioplankton was more environmentally constrained than the abundant one. Dissolved oxygen was the decisive factor in determining the balance between stochasticity and determinism in both rare and abundant bacterioplankton. Our study extends our knowledge of environmental adaptation of rare versus abundant bacterioplankton to massive disturbing measures, i.e. dredging, and allows to estimate dredging performance for mitigating cyanobacterial blooms from a molecular ecology viewpoint.
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Affiliation(s)
- Wenjie Wan
- Key Laboratory of Aquatic Botany and Watershed Ecology Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan 430074, PR China; Center of the Plant Ecology, Core Botanical Gardens, Chinese Academy of Sciences, Wuhan 430074, PR China
| | - Hans-Peter Grossart
- Leibniz-Institude of Freshwater Ecology and Inland Fisheries (IGB), 16775, Neuglobsow, Germany; University of Potsdam, Institute of Biochemistry and Biology, Maulbeerallee 2, 14469, Potsdam, Germany
| | - Donglan He
- College of Life Science, South-Central University for Nationalities, Wuhan 430070, PR China
| | - Wenke Yuan
- Key Laboratory of Aquatic Botany and Watershed Ecology Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan 430074, PR China; Center of the Plant Ecology, Core Botanical Gardens, Chinese Academy of Sciences, Wuhan 430074, PR China
| | - Yuyi Yang
- Key Laboratory of Aquatic Botany and Watershed Ecology Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan 430074, PR China; Center of the Plant Ecology, Core Botanical Gardens, Chinese Academy of Sciences, Wuhan 430074, PR China.
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21
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Silva L, Calleja ML, Ivetic S, Huete-Stauffer T, Roth F, Carvalho S, Morán XAG. Heterotrophic bacterioplankton responses in coral- and algae-dominated Red Sea reefs show they might benefit from future regime shift. Sci Total Environ 2021; 751:141628. [PMID: 32896805 DOI: 10.1016/j.scitotenv.2020.141628] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/20/2020] [Revised: 08/06/2020] [Accepted: 08/09/2020] [Indexed: 06/11/2023]
Abstract
In coral reefs, dissolved organic matter (DOM) cycling is a critical process for sustaining ecosystem functioning. However, global and local stressors have caused persistent shifts from coral- to algae-dominated benthic communities. The influence of such phase shifts on DOM nature and its utilization by heterotrophic bacterioplankton remains poorly studied. Every second month for one year, we retrieved seawater samples enriched in DOM produced by coral- and algae-dominated benthic communities in a central Red Sea reef during a full annual cycle. Seawater incubations were conducted in the laboratory under in situ temperature and light conditions by inoculating enriched DOM samples with bacterial assemblages collected in the surrounding waters. Dissolved organic carbon (DOC) concentrations were higher in the warmer months (May-September) in both communities, resulting in higher specific growth rates and bacterial growth efficiencies (BGE). However, these high summer values were significantly enhanced in algal-DOM relative to coral-DOM, suggesting the potential for bacterioplankton biomass increase in reefs with algae replacing healthy coral cover under warmer conditions. The potential exacerbation of heterotrophic bacterial activity in the ongoing widespread regime shift from coral- to algae-dominated communities may have detrimental consequences for the overall health of tropical coral reefs.
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Affiliation(s)
- Luis Silva
- King Abdullah University of Science and Technology (KAUST), Red Sea Research Center, Thuwal 23955-6900, Saudi Arabia.
| | - Maria Ll Calleja
- King Abdullah University of Science and Technology (KAUST), Red Sea Research Center, Thuwal 23955-6900, Saudi Arabia; Department of Climate Geochemistry, Max Planck Institute for Chemistry (MPIC), Hahn-Meitner-Weg 1, 55128 Mainz, Germany
| | | | - Tamara Huete-Stauffer
- King Abdullah University of Science and Technology (KAUST), Red Sea Research Center, Thuwal 23955-6900, Saudi Arabia
| | - Florian Roth
- King Abdullah University of Science and Technology (KAUST), Red Sea Research Center, Thuwal 23955-6900, Saudi Arabia; Baltic Sea Centre, Stockholm University, 11418 Stockholm, Sweden; Tvärminne Zoological Station, University of Helsinki, 00100 Helsinki, Finland
| | - Susana Carvalho
- King Abdullah University of Science and Technology (KAUST), Red Sea Research Center, Thuwal 23955-6900, Saudi Arabia
| | - Xosé Anxelu G Morán
- King Abdullah University of Science and Technology (KAUST), Red Sea Research Center, Thuwal 23955-6900, Saudi Arabia
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22
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Srinivas TNR, Sudharani P, Behera S, Dutta S, Sampath Kumar G, Sathibabu Y, Geethika G, Swagata C, Pratim Kandar P. Influence of anthropogenic activities on the spatial distribution of heterotrophic, indicator and pathogenic bacteria around Andaman and Nicobar Islands. Mar Pollut Bull 2021; 162:111839. [PMID: 33220914 DOI: 10.1016/j.marpolbul.2020.111839] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/20/2020] [Revised: 11/05/2020] [Accepted: 11/10/2020] [Indexed: 06/11/2023]
Abstract
To examine the influence of anthropogenic activities on the marine ecosystem around the Andaman and Nicobar Islands, a study was conducted to investigate the abundance of heterotrophic, indicator and pathogenic bacteria during the monsoon season. We noticed the higher abundance of heterotrophic, indicator (Escherichia coli and Enterococcus faecalis) and pathogenic bacterial counts (Aeromonas hydrophila, Enterobacter aerogens, Escherichia coli strain O157:H7, Shigella dysenteriae and Vibrio parahaemolyticus) near the 10o channel, which is the principal route to reach Andaman mainland. Most of the stations are offshore (chosen to cover shipping tracks) at a distance ranging from 41 to 266 km from the coast. The nearest station to the coast was at 21 km away. Apart from those mentioned above, several other pathogenic bacteria were also detected such as Klebsiella pneumoniae, Salmonella paratyphi, Vibrio cholera and Vibrio vulnificus but they are sparsely detected at few stations only.
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Affiliation(s)
- T N R Srinivas
- CSIR-National Institute of Oceanography, Regional Centre, 176, Lawsons Bay Colony, Visakhapatnam 530017, India.
| | - P Sudharani
- CSIR-National Institute of Oceanography, Regional Centre, 176, Lawsons Bay Colony, Visakhapatnam 530017, India
| | - Swarnaprava Behera
- CSIR-National Institute of Oceanography, Regional Centre, 176, Lawsons Bay Colony, Visakhapatnam 530017, India
| | - S Dutta
- CSIR-National Institute of Oceanography, Regional Centre, 176, Lawsons Bay Colony, Visakhapatnam 530017, India
| | - G Sampath Kumar
- CSIR-National Institute of Oceanography, Regional Centre, 176, Lawsons Bay Colony, Visakhapatnam 530017, India
| | - Y Sathibabu
- CSIR-National Institute of Oceanography, Regional Centre, 176, Lawsons Bay Colony, Visakhapatnam 530017, India
| | - G Geethika
- CSIR-National Institute of Oceanography, Regional Centre, 176, Lawsons Bay Colony, Visakhapatnam 530017, India
| | - C Swagata
- CSIR-National Institute of Oceanography, Regional Centre, 176, Lawsons Bay Colony, Visakhapatnam 530017, India
| | - P Pratim Kandar
- CSIR-National Institute of Oceanography, Regional Centre, 176, Lawsons Bay Colony, Visakhapatnam 530017, India
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23
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Gao D, Xiang T. Deammonification process in municipal wastewater treatment: Challenges and perspectives. Bioresour Technol 2021; 320:124420. [PMID: 33232853 DOI: 10.1016/j.biortech.2020.124420] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/08/2020] [Revised: 11/08/2020] [Accepted: 11/11/2020] [Indexed: 06/11/2023]
Abstract
The deammonification process has been proved to be an efficient nitrogen removal process in treating high NH4+-N concentration wastewater (sidestream deammonification). It is very hopeful to bring WWTP close to energy autarky. However, the feasibility of applying mainstream deammonification to sewage treatment need to be further explored. Therefore, this review attempts to give an overview of challenges in applying mainstream deammonification and to discuss the impacts of unfavorable conditions on main functional species. In addition, some novel control strategies to maintain the dominant position of desired species were summarized. Efficient solution to the conflict between AnAOB (Anaerobic ammonium-oxidizing bacteria) biomass retention and NOB (Nitrite oxidizing bacteria) wash out was also reviewed. Ultimately, we suggested further studies including effective improved process that achieve combination of autotrophy and organotrophy species based on the metabolic diversity of AnAOB.
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Affiliation(s)
- Dawen Gao
- School of Environment and Energy Engineering, Beijing University of Civil Engineering and Architecture, Beijing 100044, China.
| | - Tao Xiang
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, China
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24
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Zilius M, Samuiloviene A, Stanislauskienė R, Broman E, Bonaglia S, Meškys R, Zaiko A. Depicting Temporal, Functional, and Phylogenetic Patterns in Estuarine Diazotrophic Communities from Environmental DNA and RNA. Microb Ecol 2021; 81:36-51. [PMID: 32803362 DOI: 10.1007/s00248-020-01562-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/01/2020] [Accepted: 07/20/2020] [Indexed: 06/11/2023]
Abstract
Seasonally nitrogen-limited and phosphorus-replete temperate coastal waters generally host dense and diverse diazotrophic communities. Despite numerous studies in marine systems, little is known about diazotrophs and their functioning in oligohaline estuarine environments. Here we applied a combination of nifH transcript and metagenomic shotgun sequencing approaches to investigate temporal shifts in taxonomic composition and nifH activity of size-fractionated diazotrophic communities in a shallow and mostly freshwater coastal lagoon. Patterns in active nifH phylotypes exhibited a clear seasonal succession, which reflected their different tolerances to temperature change and nitrogen (N) availability. Thus, in spring, heterotrophic diazotrophs (Proteobacteria) dominated the nifH phylotypes, while increasing water temperature and depletion of inorganic N fostered heterocystous Cyanobacteria in summer. Metagenomic data demonstrated four main N-cycling pathways and three of them with a clear seasonal pattern: denitrification (spring) → N2 fixation (summer) → assimilative NO3- reduction (fall), with NH4+ uptake into cells occurring across all seasons. Although a substantial denitrification signal was observed in spring, it could have originated from the re-suspended benthic rather than planktonic community. Our results contribute to a better understanding of the realized genetic potential of pelagic N2 fixation and its seasonal dynamics in oligohaline estuarine ecosystems, which are natural coastal biogeochemical reactors.
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Affiliation(s)
- Mindaugas Zilius
- Marine Research Institute, Klaipeda University, 92294, Klaipeda, Lithuania.
| | | | - Rūta Stanislauskienė
- Department of Molecular Microbiology and Biotechnology, Institute of Biochemistry, Life Sciences Center, Vilnius University, 10257 Vilnius, Lithuania
| | - Elias Broman
- Baltic Sea Center, Stockholm University, Stockholm, Sweden
- Department of Ecology, Environment and Plant Sciences, Stockholm University, 10691 Stockholm, Sweden
| | - Stefano Bonaglia
- Marine Research Institute, Klaipeda University, 92294, Klaipeda, Lithuania
- Department of Ecology, Environment and Plant Sciences, Stockholm University, 10691 Stockholm, Sweden
- Department of Biology, University of Southern Denmark, 5230, Odense, Denmark
- Department of Marine Sciences, University of Gothenburg, Box 461, 40530 Gothenburg, Sweden
| | - Rolandas Meškys
- Department of Molecular Microbiology and Biotechnology, Institute of Biochemistry, Life Sciences Center, Vilnius University, 10257 Vilnius, Lithuania
| | - Anastasija Zaiko
- Coastal and Freshwater Group, Cawthron Institute, 7042 Nelson, New Zealand
- Institute of Marine Science, University of Auckland, Private Bag 92019, Auckland, New Zealand
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25
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Gao S, Kong Y, Yu J, Miao L, Ji L, Song L, Zeng C. Isolation of axenic cyanobacterium and the promoting effect of associated bacterium on axenic cyanobacterium. BMC Biotechnol 2020; 20:61. [PMID: 33256756 PMCID: PMC7708224 DOI: 10.1186/s12896-020-00656-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2020] [Accepted: 11/16/2020] [Indexed: 11/25/2022] Open
Abstract
Background Harmful cyanobacterial blooms have attracted wide attention all over the world as they cause water quality deterioration and ecosystem health issues. Microcystis aeruginosa associated with a large number of bacteria is one of the most common and widespread bloom-forming cyanobacteria that secret toxins. These associated bacteria are considered to benefit from organic substrates released by the cyanobacterium. In order to avoid the influence of associated heterotrophic bacteria on the target cyanobacteria for physiological and molecular studies, it is urgent to obtain an axenic M. aeruginosa culture and further investigate the specific interaction between the heterotroph and the cyanobacterium. Results A traditional and reliable method based on solid-liquid alternate cultivation was carried out to purify the xenic cyanobacterium M. aeruginosa FACHB-905. On the basis of 16S rDNA gene sequences, two associated bacteria named strain B905–1 and strain B905–2, were identified as Pannonibacter sp. and Chryseobacterium sp. with a 99 and 97% similarity value, respectively. The axenic M. aeruginosa FACHB-905A (Microcystis 905A) was not able to form colonies on BG11 agar medium without the addition of strain B905–1, while it grew well in BG11 liquid medium. Although the presence of B905–1 was not indispensable for the growth of Microcystis 905A, B905–1 had a positive effect on promoting the growth of Microcystis 905A. Conclusions The associated bacteria were eliminated by solid-liquid alternate cultivation method and the axenic Microcystis 905A was successfully purified. The associated bacterium B905–1 has the potentiality to promote the growth of Microcystis 905A. Moreover, the purification technique for cyanobacteria described in this study is potentially applicable to a wider range of unicellular cyanobacteria.
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Affiliation(s)
- Suqin Gao
- School of Biology and Pharmaceutical Engineering, Wuhan Polytechnic University, Wuhan, 430023, Hubei, China
| | - Yun Kong
- College of Resources and Environment, Yangtze University, Wuhan, 430100, Hubei, China.,Key Laboratory of Water Pollution Control and Environmental Safety of Zhejiang Province, Hangzhou, 310058, Zhejiang, China.,Yixing Academy of Environmental Protection, Nanjing University, Yixing, 214200, Jiangsu, China.,Yixing Urban Supervision & Inspection Administration of Product Quality, National Supervision & Inspection Center of Environmental Protection Equipment Quality (Jiangsu), Yixing, 214205, Jiangsu, China
| | - Jing Yu
- School of Biology and Pharmaceutical Engineering, Wuhan Polytechnic University, Wuhan, 430023, Hubei, China
| | - Lihong Miao
- School of Biology and Pharmaceutical Engineering, Wuhan Polytechnic University, Wuhan, 430023, Hubei, China.
| | - Lipeng Ji
- College of Resources and Environment, Yangtze University, Wuhan, 430100, Hubei, China
| | - Lirong Song
- Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, 430072, Hubei, China
| | - Chi Zeng
- School of Biology and Pharmaceutical Engineering, Wuhan Polytechnic University, Wuhan, 430023, Hubei, China
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26
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Kizhakkekalam VK, Chakraborty K. Seaweed-associated heterotrophic bacteria: new paradigm of prospective anti-infective and anticancer agents. Arch Microbiol 2020; 203:1241-1250. [PMID: 33140140 DOI: 10.1007/s00203-020-02106-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2020] [Revised: 10/12/2020] [Accepted: 10/19/2020] [Indexed: 12/24/2022]
Abstract
Ever since the development of the first antibiotic compound with anticancer potential, researchers focused on isolation and characterization of prospective microbial natural products with potential anti-infective and anticancer activities. The present work describes the production of bioactive metabolites by heterotrophic bacteria associated with intertidal seaweeds with potential anti-infective and anticancer activities. The bacteria were isolated in a culture-dependent method and were identified as Shewanella algae MTCC 12715 (KX272635) and Bacillus amyloliquefaciens MTCC 12716 (KX272634) based on combined phenotypic and genotypic methods. Further, the bacteria were screened for their ability to inhibit drug-resistant infectious pathogens and prevent cell proliferation of human liver carcinoma (HepG2) and breast cancer (MCF7) cell lines, without affecting the normal cells. Significant anti-infective activity was observed with bacterial cells and their organic extracts against broad-spectrum multidrug-resistant pathogens, such as vancomycin-resistant Enterococcus faecalis, methicillin-resistant Staphylococcus aureus, Klebsiella pneumonia and Pseudomonas aeruginosa with minimum inhibitory concentration ≤ 3.0 µg mL-1 as compared to the antibiotic agents' chloramphenicol and ampicillin, which were active at ≥ 6.25 mg mL-1. The extracts also exhibited anticancer activity in a dose-responsive pattern against HepG2 (with IC50, half maximal inhibitory concentration ~ 78-83 µg mL-1) and MCF7 (IC50 ~ 45-48 µg mL-1) on tetrazolium bromide screening assay with lesser cytotoxic effects on normal fibroblast (L929) cell lines (IC50 > 100 µg mL-1). The results revealed that seaweed-associated heterotrophic bacteria could occupy a predominant role for a paradigm shift towards the development of prospective anti-infective and anticancer agents.
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Affiliation(s)
- Vinaya Kizhakkepatt Kizhakkekalam
- Marine Biotechnology Division, Central Marine Fisheries Research Institute, Ernakulam North, P.B. No. 1603, Cochin, India.,Faculty of Marine Sciences, Lakeside Campus, Cochin University of Science and Technology, Cochin, Kerala State, India
| | - Kajal Chakraborty
- Marine Biotechnology Division, Central Marine Fisheries Research Institute, Ernakulam North, P.B. No. 1603, Cochin, India.
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27
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Neissi A, Rafiee G, Farahmand H, Rahimi S, Mijakovic I. Cold-Resistant Heterotrophic Ammonium and Nitrite-Removing Bacteria Improve Aquaculture Conditions of Rainbow Trout (Oncorhynchus mykiss). Microb Ecol 2020; 80:266-277. [PMID: 32162039 PMCID: PMC7371659 DOI: 10.1007/s00248-020-01498-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/01/2019] [Accepted: 02/19/2020] [Indexed: 05/31/2023]
Abstract
The aim of this study was isolation and characterization of heterotrophic bacteria capable of ammonium and nitrite removal at 15 °C (optimal temperature for growing rainbow trout Oncorhynchus mykiss). Environmental isolates were grown in liquid media containing ammonium or nitrite, and best strains in terms of growth and ammonium or nitrite removal were identified via 16S rRNA sequencing. Dyadobacter sp. (no. 68) and Janthinobacterium sp. (no. 100) were selected for optimal adaptation to growth at 15 °C and best ammonium and nitrite removal (P < 0.05), respectively. A heterotrophic ammonium and nitrite removal (HAN) microbial complex, containing selected strains, was prepared and applied in a trout culture system. After 10 days, the effect of microbial HAN complex was investigated in terms of ammonium and nitrite removal, as well as stress and immune indices present in the plasma of cultivated trout. Compared to a standard cultivation setup, addition of the HAN complex had a clear beneficial effect on keeping the un-ionized ammonia and nitrite level below prescribed standards (P < 0.05). This resulted in reduction of stress and immune reactions of cultivated fish (P < 0.05), leading to an augmentation of final weight and survival. Application of the selected microbial complex resulted in a significant improvement of the aquaculture ecosystem.
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Affiliation(s)
- Alireza Neissi
- Department of Fisheries Sciences, Faculty of Natural Resources, University of Tehran, Karaj, 331585-4314, Iran
| | - Gholamreza Rafiee
- Department of Fisheries Sciences, Faculty of Natural Resources, University of Tehran, Karaj, 331585-4314, Iran.
| | - Hamid Farahmand
- Department of Fisheries Sciences, Faculty of Natural Resources, University of Tehran, Karaj, 331585-4314, Iran
| | - Shadi Rahimi
- Division of Systems & Synthetic Biology, Department of Biology and Biological Engineering, Chalmers University of Technology, Kemivägen 10, 41296, Gothenburg, Sweden
| | - Ivan Mijakovic
- Division of Systems & Synthetic Biology, Department of Biology and Biological Engineering, Chalmers University of Technology, Kemivägen 10, 41296, Gothenburg, Sweden.
- Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, 2800, Lyngby, Denmark.
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28
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Twigg IM, Baltar F, Hall JR, Hepburn CD. Revealing hydrogen peroxide as an external stressor in macrophyte-dominated coastal ecosystems. Oecologia 2020; 193:583-591. [PMID: 32556588 DOI: 10.1007/s00442-020-04690-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2019] [Accepted: 06/11/2020] [Indexed: 10/24/2022]
Abstract
Benthic primary producers in coastal ecosystems provide important habitat for marine organisms through the provision of complex 3D habitat. Primary producers produce organic matter, while simultaneously producing reactive oxygen species, including hydrogen peroxide (H2O2), a driver of oxidative stress. Through their high biomass, productivity and effect on local hydrodynamics, benthic primary producers can potentially increase H2O2 concentrations surrounding the biogenic structures they form. The aim of this study was to identify the potential role of H2O2 produced by benthic primary producers as an external stressor in coastal ecosystems. This was achieved by measuring H2O2 concentrations within sea lettuce blooms (Ulva sp.), giant kelp forests (Macrocystis pyrifera), and seagrass meadows (Zostera muelleri); quantifying H2O2 production rates of these species; and testing heterotrophic bacterial response to relevant H2O2 concentrations. Ulva sp. produced five times more H2O2 than other species. At in situ concentrations, H2O2 inhibited bacterial production and carbon flow through the microbial loop by 75%. This study reveals H2O2 as an additional stressor in bloom-forming Ulva sp. with higher H2O2 production compared to the ecosystem engineers M. pyrifera and Z. muelleri. H2O2 production by benthic primary producers can affect carbon flow through the microbial loop, with the potential to propagate a stress signal up the food web.
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Affiliation(s)
- Isla M Twigg
- Department of Marine Science, University of Otago, Dunedin, New Zealand.
| | - Federico Baltar
- Department of Marine Science, University of Otago, Dunedin, New Zealand
- Department of Limnology and Bio-Oceanography, University of Vienna, Vienna, Austria
| | - Jack R Hall
- Department of Marine Science, University of Otago, Dunedin, New Zealand
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29
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Eswaran R, Khandeparker L. Influence of salinity stress on bacterial community composition and β-glucosidase activity in a tropical estuary: Elucidation through microcosm experiments. Mar Environ Res 2020; 159:104997. [PMID: 32662433 DOI: 10.1016/j.marenvres.2020.104997] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2020] [Revised: 04/16/2020] [Accepted: 04/16/2020] [Indexed: 06/11/2023]
Abstract
The influence of changing salinity on community composition and functional activity (Bacterial Production (BP) and ectoenzyme activity) of major bacterial taxa was evaluated using microcosm experiments in a tropical monsoon influenced estuary. Natural bacterial inocula at different salinities, representing marine, brackish, and freshwater, were inter-transferred and elucidated their response with an emphasis on community composition and β-Glucosidase (BGase) activity. The results revealed a significant decrease in the total bacterial count (TBC) and BP on the translocation of bacterial inocula to different salinity conditions in the case of freshwater bacteria. However, a significant increase in BGase activity coupled with shifts in the studied bacterial groups was evident in the case of marine as well as freshwater bacteria. Quantitative PCR (qPCR) revealed a shift in major bacterial taxa upon translocation to different waters, which was dependent on salinity and the source of inocula. Redundancy and qPCR analyses showed that members belonging to Gammaproteobacteria and Betaproteobacteria were higher, and possibly influenced BGase activity in marine and freshwater, respectively. Translocation of marine inocula to brackish and freshwater resulted in an emergence of Bacteroidetes, Actinobacteria, and Betaproteobacteria, respectively. Whereas, when freshwater inocula were translocated to marine or brackish water, Alphaproteobacteria and Gammaproteobacteria taxa emerged, and this was coupled with increased BGase activity. In contrast, brackish water bacteria showed a strong persistence in bacterial community composition when translocated to different salinities within this estuary. Such phylogenetic persistence or changes suggests species level shifts in specific bacterial taxa, and unravelling the same using different functional gene markers would ascertain their role in organic matter processing and is way forward.
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Affiliation(s)
- Ranjith Eswaran
- CSIR - National Institute of Oceanography, Dona Paula, Goa, India; School of Earth, Ocean and Atmospheric Sciences, Goa University, Taleigao, Goa, India
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30
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Kalkan S, Altuğ G. The composition of cultivable bacteria, bacterial pollution, and environmental variables of the coastal areas: an example from the Southeastern Black Sea, Turkey. Environ Monit Assess 2020; 192:356. [PMID: 32394090 DOI: 10.1007/s10661-020-08310-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/11/2019] [Accepted: 04/21/2020] [Indexed: 06/11/2023]
Abstract
The composition and metabolic properties of cultivable heterotrophic aerobic bacteria, the levels of indicator bacteria, and physicochemical parameters were investigated in the seawater samples collected from 20 stations in coastal areas of the eastern part of the Black Sea, Turkey, between May 2017 and February 2018. The levels of indicator bacteria were detected above the national limit values during the study period. Thirty-five different bacterium species were identified. Enterobacteriaceae was recorded as the most dominant family (34.2%), and Gammaproteobacteria was recorded as the most dominant class (74.2%). Bacteriological threats on human and ecosystem health were determined in coastal areas of the Southeastern Black Sea. The determination of the high levels of indicator bacteria, the high ratio of fecal coliform/fecal streptococci (FC/FS ratio), and pathogenic bacteria regarding human and ecosystem health showed that these coastal areas under the influences of terrestrial and human-sourced bacteriological pollution. This study has contributed to the increase of knowledge of understanding the protection and rehabilitation ways of the Black Sea coastal regions against land-based pollution sources considering the interdependent structure of all Black Sea countries. Coastal areas are accepted as the most fragile part of the marine environments and our findings showed the potential bacteriological risks in coastal areas of the Southeastern Black Sea as an important example. Serious precautions should be taken for the protection in this area and such coastal ecosystems to prevent hazardous problems.
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Affiliation(s)
- Samet Kalkan
- Faculty of Fisheries, Recep Tayyip Erdogan University, Ataturk Street Fener District, 53100, Merkez, Rize, Turkey.
| | - Gülşen Altuğ
- Faculty of Aquatic Sciences, Istanbul University, Ordu Street No 200, 34470, Laleli, Istanbul, Turkey
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31
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El-Serehy HA, Shafik H, Abdallah HS, Al-Misned FA, Al-Farraj SA. Complex interactions and different possible pathways among functional components of the aquatic microbial world in Farasan Archipelago, Southern Red Sea, Saudi Arabia. Saudi J Biol Sci 2020; 27:1412-1417. [PMID: 32346354 PMCID: PMC7182789 DOI: 10.1016/j.sjbs.2019.12.012] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2019] [Revised: 12/03/2019] [Accepted: 12/08/2019] [Indexed: 11/30/2022] Open
Abstract
This work aims to outline the dynamics of trophic links between the three main microbial components (bacteria, nanoflagellates, and ciliates) of the Farasan Archipelago in order to establish a baseline for future research in this area. The Farasan Archipelago lies along the southwestern coast of the Saudi Arabia, southern Red Sea between 16°20′–17°10′N and 41°30′–42°30′E and had been declared as marine and terrestrial reserve by the year 1996. Three different sites were chosen for this study, with each site visited bimonthly for 18 months from September 2016 to February 2018. Bacteria, nanoflagellates and ciliates were enumerated in order to explore the complex interactions between the main microbial categories in sea waters of the Farasan Archipelago. High abundances were recorded during the present study for bacteria (8.7 × 106 bacteria ml−1), nanoflagellates (3.7 × 104 TNAN ml−1) and ciliates (40.4 ciliates ml−1). The paper discusses the various potential pathways controlling the complex interactions between these microbial groups in this part of the southern Red Sea. It is concluded that a linear trophic chain consisting of bacteria; heterotrophic nanoflagellates; filter feeding ciliates is a major route by which the production of bacteria is transferred to the higher consuming levels, thereby confirming the high importance of t bottom-up control (food supply), alongside top-down control (predation) in regulating bacterial abundances in the Farasan Archipelago. During the present investigation, each nanoflagellate ingested between 11 and 87 bacteria in one hour, while each ciliate consumed between 20 and 185 nanoflagellates every hour. These calculated grazing rates of protistan eukaryotes confirmed the role of heterotrophic nanoflagellates as the main consumers of bacteria, and the role of ciliates as the major control for the heterotrophic nanoflagellate population dynamics, and thus the top predators within the microbial plankton assemblage in the Farasan Archipelago.
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Affiliation(s)
- Hamed A El-Serehy
- Department of Zoology, College of Science, King Saud University, Riyadh, Saudi Arabia.,Department of Oceanography, College of Science, Port Said University, Port Said, Egypt
| | - Hesham Shafik
- Balaton Limnological Research Institute of the Hungarian Academy of Sciences, Tihany, Hungary
| | - Hala S Abdallah
- Department of Computer Science, College of Science and Arts, Campus 1, Khamis Mushait, King Khaled University, Saudi Arabia.,Department of Mathematics, Faculty of Science, Suez Canal University, Ismailia, Egypt
| | - Fahad A Al-Misned
- Department of Zoology, College of Science, King Saud University, Riyadh, Saudi Arabia
| | - Saleh A Al-Farraj
- Department of Zoology, College of Science, King Saud University, Riyadh, Saudi Arabia
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32
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Li J, Li J, Peng Y, Wang S, Zhang L, Yang S, Li S. Insight into the impacts of organics on anammox and their potential linking to system performance of sewage partial nitrification-anammox (PN/A): A critical review. Bioresour Technol 2020; 300:122655. [PMID: 31926793 DOI: 10.1016/j.biortech.2019.122655] [Citation(s) in RCA: 90] [Impact Index Per Article: 22.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/21/2019] [Revised: 12/16/2019] [Accepted: 12/18/2019] [Indexed: 06/10/2023]
Abstract
Partial nitrification-anammox (PN/A) is an energy-efficient process for nitrogen removal from sewage. The influent organics of sewage is usually pre-removed, reducing the risk for enriching anammox bacteria (AnAOB). However, recent studies demonstrate that optimum influent organics could improve nitrogen removal and operational stability of PN/A. Thus, the impact of organics on PN/A-based process should not be overlooked. In this review, the complicated impacts of organics-containing influent on anammox and their linking to apply PN/A are discussed. Firstly, the effect of organics on AnAOB metabolism and the competition relationship between AnAOB and heterotrophic bacteria are summarized. Secondly, the combined effects of influent organics and operational strategies on PN/A-based process were reviewed. Thirdly, how to control influent organics in the real application of PN/A were discussed. Lastly, recent development of the PN/A-based process combined with denitrification were reviewed. Overall, influent organics could be an essential factor for successful application of sewage PN/A.
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Affiliation(s)
- Jialin Li
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Key Laboratory of Beijing for Water Quality Science and Water Environment Recovery Engineering, Beijing University of Technology, Beijing 100124, China
| | - Jianwei Li
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Key Laboratory of Beijing for Water Quality Science and Water Environment Recovery Engineering, Beijing University of Technology, Beijing 100124, China
| | - Yongzhen Peng
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Key Laboratory of Beijing for Water Quality Science and Water Environment Recovery Engineering, Beijing University of Technology, Beijing 100124, China
| | - Shuying Wang
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Key Laboratory of Beijing for Water Quality Science and Water Environment Recovery Engineering, Beijing University of Technology, Beijing 100124, China
| | - Liang Zhang
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Key Laboratory of Beijing for Water Quality Science and Water Environment Recovery Engineering, Beijing University of Technology, Beijing 100124, China.
| | - Shenhua Yang
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Key Laboratory of Beijing for Water Quality Science and Water Environment Recovery Engineering, Beijing University of Technology, Beijing 100124, China
| | - Shuai Li
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Key Laboratory of Beijing for Water Quality Science and Water Environment Recovery Engineering, Beijing University of Technology, Beijing 100124, China
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33
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Al-Otaibi N, Huete-Stauffer TM, Calleja ML, Irigoien X, Morán XAG. Seasonal variability and vertical distribution of autotrophic and heterotrophic picoplankton in the Central Red Sea. PeerJ 2020; 8:e8612. [PMID: 32140305 PMCID: PMC7045887 DOI: 10.7717/peerj.8612] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2019] [Accepted: 01/21/2020] [Indexed: 12/21/2022] Open
Abstract
The Red Sea is characterized by higher temperatures and salinities than other oligotrophic tropical regions. Here, we investigated the vertical and seasonal variations in the abundance and biomass of autotrophic and heterotrophic picoplankton. Using flow cytometry, we consistently observed five groups of autotrophs (Prochlorococcus, two populations of Synechococcus separated by their relative phycoerythrin fluorescence, low (LF-Syn) and high (HF-Syn), and two differently-sized groups of picoeukaryotes, small (Speuk) and large (Lpeuk)) and two groups of heterotrophic prokaryotes of low and high nucleic acid content (LNA and HNA, respectively). Samples were collected in 15 surveys conducted from 2015 to 2017 at a 700-m depth station in the central Red Sea. Surface temperature ranged from 24.6 to 32.6 °C with a constant value of 21.7 °C below 200 m. Integrated (0-100 m) chlorophyll a concentrations were low, with maximum values in fall (24.0 ± 2.7 mg m-2) and minima in spring and summer (16.1 ± 1.9 and 1.1 mg m-2, respectively). Picoplankton abundance was generally lower than in other tropical environments. Vertical distributions differed for each group, with Synechococcus and LNA prokaryotes more abundant at the surface while Prochlorococcus, picoeukaryotes and HNA prokaryotes peaked at the deep chlorophyll maximum, located between 40 and 76 m. Surface to 100 m depth-weighted abundances exhibited clear seasonal patterns for Prochlorococcus, with maxima in summer (7.83 × 104 cells mL-1, July 2015) and minima in winter (1.39 × 104 cells mL-1, January 2015). LF-Syn (0.32 - 2.70 × 104 cells mL-1 ), HF-Syn (1.11 - 3.20 × 104 cells mL-1) and Speuk (0.99 - 4.81 × 102 cells mL-1) showed an inverse pattern to Prochlorococcus, while Lpeuk (0.16 - 7.05 × 104 cells mL-1) peaked in fall. Synechococcus unexpectedly outnumbered Prochlorococcus in winter and at the end of fall. The seasonality of heterotrophic prokaryotes (2.29 - 4.21×105 cells mL-1 ) was less noticeable than autotrophic picoplankton. The contribution of HNA cells was generally low in the upper layers, ranging from 36% in late spring and early summer to ca. 50% in winter and fall. Autotrophs dominated integrated picoplankton biomass in the upper 100 m, with 1.4-fold higher values in summer than in winter (mean 387 and 272 mg C m-2, respectively). However, when the whole water column was considered, the biomass of heterotrophic prokaryotes exceeded that of autotrophic picoplankton with an average of 411 mg C m-2. Despite being located in tropical waters, our results show that the picoplankton community seasonal differences in the central Red Sea are not fundamentally different from higher latitude regions.
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Affiliation(s)
- Najwa Al-Otaibi
- Red Sea Research Center (RSRC), Division of Biological and Environmental Sciences and Engineering, King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
| | - Tamara M Huete-Stauffer
- Red Sea Research Center (RSRC), Division of Biological and Environmental Sciences and Engineering, King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
| | - Maria Ll Calleja
- Department of Climate Geochemistry, Max Planck Institute for Chemistry (MPIC), Mainz, Germany
| | - Xabier Irigoien
- AZTI - Marine Research, Pasaia, Spain.,Basque Foundation for Science, IKERBASQUE, Bilbao, Spain
| | - Xosé Anxelu G Morán
- Red Sea Research Center (RSRC), Division of Biological and Environmental Sciences and Engineering, King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
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Ramírez S, Torrealba G, Lameda-Cuicas E, Molina-Quintero L, Stefanakis AI, Pire-Sierra MC. Investigation of pilot-scale constructed wetlands treating simulated pre-treated tannery wastewater under tropical climate. Chemosphere 2019; 234:496-504. [PMID: 31229710 DOI: 10.1016/j.chemosphere.2019.06.081] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/25/2019] [Revised: 05/22/2019] [Accepted: 06/09/2019] [Indexed: 06/09/2023]
Abstract
Tannery wastewater is characterized by high and variable concentrations of diverse pollutants, which makes it difficult and costly to treat. In the search for sustainable treatment options for tannery effluents, two pilot-scale horizontal subsurface flow (HSF) constructed wetlands (CW) were built and operated for the treatment of synthetic water of quality similar to that of pre-treated tannery effluents. Five different loading phases were examined with gradual increase of inflow COD, NH4+-N and Cr loads until reaching and exceeding the typical composition of a tannery effluent. High COD and NH4+-N removals were observed (82 and 96%, respectively), and almost complete Cr removal in the outflow, which met the Venezuela national standards for environmental discharge. Plant uptake was measured, but microbial processes appear to be the main ammonium transformation/removal mechanism. Nitrogen, chlorophyll and Cr in the plant aerial parts and roots indicated the capacity of Phragmites sp. to grow and survive even under high loads. The measured heterotrophic bacteria in the substrate and rhizomes indicated the biofilm development and the oxidation of organic matter and nitrogen. Water losses via evapotraspiration were also measured and reached 14%. Overall, the tested CW design proved to be a sustainable and feasible alternative for the treatment of tannery wastewater in tropical climates.
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Affiliation(s)
- Susana Ramírez
- Environmental Research Laboratory, Department of Ecology and Quality Control, Agroindustrial Engineering Program, Centroccidental University "Lisandro Alvarado", Barquisimeto, Venezuela
| | - Graciela Torrealba
- Microbiology Laboratory, Department of Ecology and Quality Control, Agroindustrial Engineering Program, Centroccidental University "Lisandro Alvarado", Barquisimeto, Venezuela
| | - Eudimar Lameda-Cuicas
- Environmental Research Laboratory, Department of Ecology and Quality Control, Agroindustrial Engineering Program, Centroccidental University "Lisandro Alvarado", Barquisimeto, Venezuela; Microbiology Laboratory, Department of Ecology and Quality Control, Agroindustrial Engineering Program, Centroccidental University "Lisandro Alvarado", Barquisimeto, Venezuela
| | - Luisa Molina-Quintero
- Microbiology Laboratory, Department of Ecology and Quality Control, Agroindustrial Engineering Program, Centroccidental University "Lisandro Alvarado", Barquisimeto, Venezuela
| | | | - Maria Carolina Pire-Sierra
- Environmental Research Laboratory, Department of Ecology and Quality Control, Agroindustrial Engineering Program, Centroccidental University "Lisandro Alvarado", Barquisimeto, Venezuela
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Wu C, Kan J, Liu H, Pujari L, Guo C, Wang X, Sun J. Heterotrophic Bacteria Dominate the Diazotrophic Community in the Eastern Indian Ocean (EIO) during Pre-Southwest Monsoon. Microb Ecol 2019; 78:804-819. [PMID: 31037377 DOI: 10.1007/s00248-019-01355-1] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/12/2018] [Accepted: 03/05/2019] [Indexed: 06/09/2023]
Abstract
The diazotrophic communities play an important role in sustaining primary productivity through adding new nitrogen to oligotrophic marine ecosystems. Yet, their composition in the oligotrophic Indian Ocean is poorly understood. Here, we report the first observation of phylogenetic diversity and distribution of diazotrophs in the Eastern Indian Ocean (EIO) surface water (to 200 m) during the pre-southwest monsoon period. Through high throughput sequencing of nifH genes, we identified diverse groups of diazotrophs in the EIO including both non-cyanobacterial and cyanobacterial phylotypes. Proteobacteria (mainly Alpha-, Beta-, and Gamma-proteobacteria) were the most diverse and abundant groups within all the diazotrophs, which accounted for more than 86.9% of the total sequences. Cyanobacteria were also retrieved, and they were dominated by the filamentous non-heterocystous cyanobacteria Trichodesmium spp. Other cyanobacteria such as unicellular diazotrophic cyanobacteria were detected sporadically. Interestingly, our qPCR analysis demonstrated that the depth-integrated gene abundances of the diazotrophic communities exhibited spatial heterogeneity with Trichodesmium spp. appeared to be more abundant in the Bay of Bengal (p < 0.05), while Sagittula castanea (Alphaproteobacteria) was found to be more dominating in the equatorial region and offshores (p < 0.05). Non-metric multidimensional scaling analysis (NMDS) further confirmed distinct vertical and horizontal spatial variations in the EIO. Canonical correspondence analysis (CCA) indicated that temperature, salinity, and phosphate were the major environmental factors driving the distribution of the diazotroph communities. Overall, our study provides the first insight into the diversity and distribution of the diazotrophic communities in EIO. The findings from this study highlight distinct contributions of both non-cyanobacteria and cyanobacteria to N2 fixation. Moreover, our study reveals information that is critical for understanding spatial heterogeneity and distribution of diazotrophs, and their vital roles in nitrogen and carbon cycling.
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Affiliation(s)
- Chao Wu
- Institute of Marine Science and Technology, Shandong University, Qingdao, 266237, China
| | - Jinjun Kan
- Microbiology Division, Stroud Water Research Center, Avondale, PA, 19311, USA
| | - Haijiao Liu
- Institute of Marine Science and Technology, Shandong University, Qingdao, 266237, China
| | - Laxman Pujari
- Tianjin Key Laboratory of Marine Resources and Chemistry, Tianjin University of Science and Technology, Tianjin, 300457, China
- Research Centre for Indian Ocean Ecosystem, Tianjin University of science and Technology, Tianjin, 300457, China
| | - Congcong Guo
- Tianjin Key Laboratory of Marine Resources and Chemistry, Tianjin University of Science and Technology, Tianjin, 300457, China
- Research Centre for Indian Ocean Ecosystem, Tianjin University of science and Technology, Tianjin, 300457, China
| | - Xingzhou Wang
- Tianjin Key Laboratory of Marine Resources and Chemistry, Tianjin University of Science and Technology, Tianjin, 300457, China
- Research Centre for Indian Ocean Ecosystem, Tianjin University of science and Technology, Tianjin, 300457, China
| | - Jun Sun
- Tianjin Key Laboratory of Marine Resources and Chemistry, Tianjin University of Science and Technology, Tianjin, 300457, China.
- Research Centre for Indian Ocean Ecosystem, Tianjin University of science and Technology, Tianjin, 300457, China.
- College of Marine & Environmental Sciences, Tianjin University of Science and Technology, No.29 13th Avenue, TEDA, Tianjin, 300457, People's Republic of China.
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Eswaran R, Khandeparker L. Seasonal variation in β-glucosidase-producing culturable bacterial diversity in a monsoon-influenced tropical estuary. Environ Monit Assess 2019; 191:662. [PMID: 31650269 DOI: 10.1007/s10661-019-7818-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/08/2019] [Accepted: 09/11/2019] [Indexed: 06/10/2023]
Abstract
The episodic monsoon condition in a tropical estuarine environment inputs high allochthonous materials that are rich in carbohydrates and are mainly broken down by enzymatic hydrolysis thus alter both organic matter and microbial community composition of an estuary. β-Glucosidases are one of the enzymes mediating the degradation of carbohydrates and are majorly produced by heterotrophic bacteria. The present study elucidated β-glucosidase-producing culturable bacterial diversity and measured their activity during non-monsoon and monsoon seasons in Zuari estuary. The results revealed that both bacterial abundance and β-glucosidase activity decreased significantly from non-monsoon to monsoon, whereas phylogenetic diversity increased. Majority of β-glucosidase producers during non-monsoon belonged to the members of Bacillales (53%), Pseudomonadales (26%), and Vibrionales (11%) which shifted to the members of Enterobacteriales (51%), Bacillales (14%), Alteromonadales (12%), Aeromonadales (9%), Xanthomonadales (7%), Pseudomonadales (5%), and Flavobacteriales (2%) during the monsoon. The shift in bacterial community structure points out the occurrence of different allochthonous forms with carbohydrate-metabolizing ability during the monsoon, and their relevance in ecology and health of this estuary can be elucidated by studying their functional diversity and is a step ahead.
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Affiliation(s)
- Ranjith Eswaran
- CSIR-National Institute of Oceanography, Dona Paula, Goa, 403004, India
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Okubo K, Ito T, Shiota Y, Kawata Y, Yamamoto T, Takashiba S. Effectiveness and safety of low-concentrated ozonized water for the reduction of contamination in dental unit water lines. Heliyon 2019; 5:e02306. [PMID: 31463403 PMCID: PMC6710486 DOI: 10.1016/j.heliyon.2019.e02306] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2018] [Revised: 05/09/2019] [Accepted: 08/09/2019] [Indexed: 11/30/2022] Open
Abstract
Contamination of dental unit waterlines (DUWL) with heterotrophic bacteria can cause problems in immune compromised patients (aged, tumor and organ transplantation-patients). We focused on the use of low-concentrated ozonized water (OZW) as the biofilm formation restraint system for DUWL. Here, we examined the effects of low-concentrated OZW on the growth of bacteria and related biofilm formation and harmfulness to dental unit components (DUCs) in vitro. OBJECTIVES To evaluate the bactericidal effects of OZW on biofilms in DUWL and DUC in vitro. METHODS Low-concentrated OZW (0.4 mg/L) was generated using an OZS-PTDX generator. Heterotrophic bacterial biofilms in old DUWL tubes and Candia albicans solution (control microbe) were treated with OZW for 1 h with gentle agitation before static culturing for 96 h in Reasoner's 2A liquid media. The control solutions were 0.1% cetylpyridinium chloride (CPC), chlorinated tap water (TW), and phosphate-buffered saline (PBS). Adenosine triphosphate (ATP) amounts of the microbes were measured and the biofilms of these microbes were observed using scanning electron microscopy (SEM). Moreover, surfaces of DUC soaked in OZW and TW were observed by SEM. RESULTS The OZW reduced ATP levels in microbes to 50% compared to TW and PBS treatment, although CPC reduced it below detection limits. SEM observation revealed deformation of microbes cultured with OZW, whereas no changes were seen on DUC surfaces. CONCLUSIONS Low-concentrated OZW is bactericidal against heterotrophic bacteria biofilms and it is not harmful to DUC, suggesting that it might be useful in preventing DUWL contamination.
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Affiliation(s)
- Keisuke Okubo
- Department of Pathophysiology - Periodontal Science, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, 2-5-1 Shikata-cho, Kita-ku, Okayama, 700-8525, Japan
- Division of Dentistry, Tottori Municipal Hospital, 1-1 Matoba, Tottori, 680-8501, Japan
| | - Takashi Ito
- Center for Innovative Clinical Medicine, Okayama University Hospital, 2-5-1 Shikata-cho, Kita-ku, Okayama, 700-8525, Japan
| | - Yasuyoshi Shiota
- Department of Pathophysiology - Periodontal Science, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, 2-5-1 Shikata-cho, Kita-ku, Okayama, 700-8525, Japan
- Division of Dentistry, National Hospital Organization Shikoku Cancer Center, 160 Minamiumemoto-cho-ko, Matuyama, 791-0280, Japan
| | - Yusuke Kawata
- Department of Pathophysiology - Periodontal Science, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, 2-5-1 Shikata-cho, Kita-ku, Okayama, 700-8525, Japan
| | - Tadashi Yamamoto
- Department of Pathophysiology - Periodontal Science, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, 2-5-1 Shikata-cho, Kita-ku, Okayama, 700-8525, Japan
| | - Shogo Takashiba
- Department of Pathophysiology - Periodontal Science, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, 2-5-1 Shikata-cho, Kita-ku, Okayama, 700-8525, Japan
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Kraiem K, Wahab MA, Kallali H, Fra-Vazquez A, Pedrouso A, Mosquera-Corral A, Jedidi N. Effects of short- and long-term exposures of humic acid on the Anammox activity and microbial community. Environ Sci Pollut Res Int 2019; 26:19012-19024. [PMID: 30039484 DOI: 10.1007/s11356-018-2786-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/15/2018] [Accepted: 07/17/2018] [Indexed: 06/08/2023]
Abstract
Humic acid has a controversial effect on the biological treatment processes. Here, we have investigated humic acid effects on the Anammox activity by studying the nitrogen removal efficiencies in batch and continuous conditions and analyzing the microbial community using Fluorescence in situ hybridization (FISH) technique. The results showed that the Anammox activity was affected by the presence of humic acid at a concentration higher than 70 mg/L. In fact, in the presence of humic acid concentration of 200 mg/L, the Anammox activity decreased to 57% in batch and under continuous condition, the ammonium removal efficiencies of the reactor decreased from 78 to 41%. This reduction of Anammox activity after humic acid addition was highlighted by FISH analysis which revealed a considerable reduction of the abundance of Anammox bacteria and the bacteria living in symbiosis with them. Furthermore, a total inhibition of Candidatus Brocadia fulgida was observed. However, humic acid has promoted heterotrophic denitrifying bacteria which became dominant in the reactor. In fact, the evolution of the organic matter in the reactor showed that the added humic acid was used as carbon source by heterotrophic bacteria which explained the shift of metabolism to the favor of heterotrophic denitrifying bacteria. Accordingly, humic acid should be controlled in the influent to avoid Anammox activity inhibition.
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Affiliation(s)
- Khadija Kraiem
- Laboratory of Wastewater Treatment and Valorization, Water Research and Technologies Center, CERTE, Technopark Tourist Route of Soliman Nabeul, PO Box No. 273, 8020, Soliman, Tunisia
- Faculty of Sciences of Tunis, University of Tunis El Manar, Rommana, B.P. no. 94, 1068, Tunis, Tunisia
| | - Mohamed Ali Wahab
- Laboratory of Wastewater Treatment and Valorization, Water Research and Technologies Center, CERTE, Technopark Tourist Route of Soliman Nabeul, PO Box No. 273, 8020, Soliman, Tunisia.
| | - Hamadi Kallali
- Laboratory of Wastewater Treatment and Valorization, Water Research and Technologies Center, CERTE, Technopark Tourist Route of Soliman Nabeul, PO Box No. 273, 8020, Soliman, Tunisia
| | - Andrea Fra-Vazquez
- Department of Chemical Engineering, Institute of Technological Research, School of Engineering, Universidade de Santiago de Compostela, Rua Lope Gómez de Marzoa s/n, 15782, Santiago de Compostela, Spain
| | - Alba Pedrouso
- Department of Chemical Engineering, Institute of Technological Research, School of Engineering, Universidade de Santiago de Compostela, Rua Lope Gómez de Marzoa s/n, 15782, Santiago de Compostela, Spain
| | - Anuska Mosquera-Corral
- Department of Chemical Engineering, Institute of Technological Research, School of Engineering, Universidade de Santiago de Compostela, Rua Lope Gómez de Marzoa s/n, 15782, Santiago de Compostela, Spain
| | - Naceur Jedidi
- Laboratory of Wastewater Treatment and Valorization, Water Research and Technologies Center, CERTE, Technopark Tourist Route of Soliman Nabeul, PO Box No. 273, 8020, Soliman, Tunisia
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Nguyen VK, Nguyen TH, Ha MG, Kang HY. Kinetics of microbial selenite reduction by novel bacteria isolated from activated sludge. J Environ Manage 2019; 236:746-754. [PMID: 30772731 DOI: 10.1016/j.jenvman.2019.02.012] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/22/2018] [Revised: 01/19/2019] [Accepted: 02/02/2019] [Indexed: 06/09/2023]
Abstract
A total of three bacteria isolated from activated sludge of a wastewater treatment plant were found to reduce selenite to elemental selenium nanoparticles as both amorphous nanospheres and monoclinic nanocrystals. The three isolated strains, which are potential candidates for bioremediation of selenite-contaminated water sources, were designated as Citrobacter sp. NVK-2, Providencia sp. NVK-2A, and Citrobacter sp. NVK-6 based on 16S rRNA sequencing. Despite belonging to the same genus, the kinetics of selenite reduction by strain NVK-2 (Vmax = 58.82 μM h-1, Km = 3737.12 μM) completely differed from that of strain NVK-6 (Vmax = 19.23 μM h-1, Km = 1300.17 μM). The selenite reduction rate by strain NVK-2A (Vmax = 9.26 μM h-1, Km = 3044.73 μM) was the slowest among the investigated microorganisms. The microbial selenite reduction rates according to various organic sources indicated that simple organic sources such as acetate and lactate were better than more complex organic sources such as propionate, butyrate, and glucose for selenite removal. Interestingly, the selenite reduction rate was significantly enhanced when the organic source was strategically divided into small portions and consecutively supplied to the culture.
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Affiliation(s)
- Van Khanh Nguyen
- Department of Microbiology, Pusan National University, Busan 46241, Republic of Korea.
| | - Trung Hau Nguyen
- Department of Biotechnology, Pukyong National University, Busan 48513, Republic of Korea
| | - Myung-Gyu Ha
- Korea Basic Science Institute, Busan Center, Busan 46742, Republic of Korea
| | - Ho Young Kang
- Department of Microbiology, Pusan National University, Busan 46241, Republic of Korea.
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Frank H, Fussmann KE, Rahav E, Bar Zeev E. Chronic effects of brine discharge form large-scale seawater reverse osmosis desalination facilities on benthic bacteria. Water Res 2019; 151:478-487. [PMID: 30641463 DOI: 10.1016/j.watres.2018.12.046] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/06/2018] [Revised: 11/15/2018] [Accepted: 12/08/2018] [Indexed: 06/09/2023]
Abstract
Seawater desalination facilities continuously discharge hyper-saline brine into the coastal environment which often flows as a concentrated plume over the seafloor, hence possibly impacting benthic microorganisms. Yet, the effects of brine discharge from desalination plants on benthic bacteria, key players in biodegradation of organic material and nutrient recycling is unknown. In this study, we tested the chronic (years) effects of brine discharge from three large-scale desalination facilities on the abundance, metabolic activity and community composition of benthic bacteria. To this end, four sampling campaigns were carried at the outfall areas of the Ashkelon, Sorek and Hadera desalination facilities. The effects of the brine were compared to corresponding reference stations which were not influenced by the brine (i.e., water temperature and salinity). Our sampling data indicate that bacterial abundance and activity that includes bacterial growth efficiency were 1.3-2.6-fold higher at the outfall area than the reference station. Concomitant analysis pointed out that the bacterial community structure at the brine discharge area was also different than the reference station, yet varied between each desalination facility. Our results demonstrate that the impact of brine effluent from desalination facilities on benthic bacteria are site-specific and localized (<1.4 Km2) around the discharge point. Namely, that the effects on benthic bacteria are prominent at the brine mixing zone and change according to the discharge method used to disperse the brine as well as local stressors (e.g., eutrophication and elevated water temperature). Our results contribute new insights on the effects of desalination-brine to benthic microbes, while providing scientifically-based aspects on the ecological impacts of brine dispersion for decision makers.
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Affiliation(s)
- Hila Frank
- Zuckerberg Institute for Water Research (ZIWR), The Jacob Blaustein Institutes for Desert Research (BIDR) Ben-Gurion University of the Negev, 84990, Israel; Israel Oceanographic and Limnological Research, National Institute of Oceanography, Haifa, 8030, Israel
| | - Katarina E Fussmann
- Zuckerberg Institute for Water Research (ZIWR), The Jacob Blaustein Institutes for Desert Research (BIDR) Ben-Gurion University of the Negev, 84990, Israel; Israel Oceanographic and Limnological Research, National Institute of Oceanography, Haifa, 8030, Israel
| | - Eyal Rahav
- Israel Oceanographic and Limnological Research, National Institute of Oceanography, Haifa, 8030, Israel.
| | - Edo Bar Zeev
- Zuckerberg Institute for Water Research (ZIWR), The Jacob Blaustein Institutes for Desert Research (BIDR) Ben-Gurion University of the Negev, 84990, Israel.
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Abstract
Many industrial activities produce H2S, which is toxic at high levels and odorous at even very low levels. Chemolithotrophic sulfur-oxidizing bacteria are often used in its remediation. Recently, we have reported that many heterotrophic bacteria can use sulfide:quinone oxidoreductase and persulfide dioxygenase to oxidize H2S to thiosulfate and sulfite. These bacteria may also potentially be used in H2S biotreatment. Here we report how various heterotrophic bacteria with these enzymes were cultured with organic compounds and the cells were able to rapidly oxidize H2S to zero-valence sulfur and thiosulfate, causing no apparent acidification. Some also converted the produced thiosulfate to tetrathionate. The rates of sulfide oxidation by some of the tested bacteria in suspension, ranging from 8 to 50 µmol min−1 g−1 of cell dry weight at pH 7.4, sufficient for H2S biotreatment. The immobilized bacteria removed H2S as efficiently as the bacteria in suspension, and the inclusion of Fe3O4 nanoparticles during immobilization resulted in increased efficiency for sulfide removal, in part due to chemical oxidation H2S by Fe3O4. Thus, heterotrophic bacteria may be used for H2S biotreatment under aerobic conditions.
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Affiliation(s)
- Ningke Hou
- State Key Laboratory of Microbial Technology, Shandong University, Jinan, 250100, People's Republic of China
| | - Yongzhen Xia
- State Key Laboratory of Microbial Technology, Shandong University, Jinan, 250100, People's Republic of China
| | - Xia Wang
- State Key Laboratory of Microbial Technology, Shandong University, Jinan, 250100, People's Republic of China
| | - Huaiwei Liu
- State Key Laboratory of Microbial Technology, Shandong University, Jinan, 250100, People's Republic of China
| | - Honglei Liu
- State Key Laboratory of Microbial Technology, Shandong University, Jinan, 250100, People's Republic of China.
| | - Luying Xun
- State Key Laboratory of Microbial Technology, Shandong University, Jinan, 250100, People's Republic of China.
- School of Molecular Biosciences, Washington State University, Pullman, WA, 99164-7520, USA.
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Kassotaki E, Pijuan M, Joss A, Borrego CM, Rodriguez-Roda I, Buttiglieri G. Unraveling the potential of a combined nitritation-anammox biomass towards the biodegradation of pharmaceutically active compounds. Sci Total Environ 2018; 624:722-731. [PMID: 29272841 DOI: 10.1016/j.scitotenv.2017.12.116] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/02/2017] [Revised: 12/07/2017] [Accepted: 12/11/2017] [Indexed: 06/07/2023]
Abstract
In the past few years, anaerobic ammonium oxidation-based processes have attracted a lot of attention for their implementation at the mainstream line of wastewater treatment plants, due to the possibility of leading to energy autarky if combined with anaerobic digestion. However, little is known about the potential degradation of micropollutants by the microbial groups responsible of these processes and the few results available are inconclusive. This study aimed to assess the degradation capability of biomass withdrawn from a combined nitritation/anaerobic ammonium oxidation (combined N/A) pilot plant towards five pharmaceutically active compounds (ibuprofen, sulfamethoxazole, metoprolol, venlafaxine and carbamazepine). Batch experiments were performed under different conditions by selectively activating or inhibiting different microbial groups: i) regular combined N/A operation, ii) aerobic (optimal for nitrifying bacteria), iii) aerobic with allylthiourea (an inhibitor of ammonia monooxygenase, enzyme of ammonia oxidizing bacteria), iv) anoxic (optimal for anaerobic ammonium oxidizing bacteria), v) aerobic with acetate (optimal for heterotrophic bacteria) and vi) anoxic with acetate (optimal for heterotrophic denitrifying bacteria). Ibuprofen was the most biodegradable compound being significantly degraded (49-100%) under any condition except heterotrophic denitrification. Sulfamethoxazole, exhibited the highest removal (70%) under optimal conditions for nitrifying bacteria but in the rest of the experiments anoxic conditions were found to be slightly more favorable (up to 58%). For metoprolol the highest performance was obtained under anoxic conditions favoring anammox bacteria (62%). Finally, carbamazepine and venlafaxine were hardly removed (≤10% in the majority of cases). Taken together, these results suggest the specificity of different microbial groups that in combination with alternating operational parameters can lead to enhanced removal of some micropollutants.
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Affiliation(s)
- Elissavet Kassotaki
- ICRA, Catalan Institute for Water Research, Scientific and Technological Park of the University of Girona, 17003 Girona, Spain.
| | - Maite Pijuan
- ICRA, Catalan Institute for Water Research, Scientific and Technological Park of the University of Girona, 17003 Girona, Spain.
| | - Adriano Joss
- Eawag, Swiss Federal Institute of Aquatic Science and Technology, Überlandstr. 133, 8600 Dübendorf, Switzerland.
| | - Carles M Borrego
- ICRA, Catalan Institute for Water Research, Scientific and Technological Park of the University of Girona, 17003 Girona, Spain; Group of Molecular Microbial Ecology, Institute of Aquatic Ecology, University of Girona, Girona, Spain.
| | - Ignasi Rodriguez-Roda
- ICRA, Catalan Institute for Water Research, Scientific and Technological Park of the University of Girona, 17003 Girona, Spain; LEQUiA, Laboratory of Chemical and Environmental Engineering, University of Girona, Campus Montilivi, 17071 Girona, Spain.
| | - Gianluigi Buttiglieri
- ICRA, Catalan Institute for Water Research, Scientific and Technological Park of the University of Girona, 17003 Girona, Spain.
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Peng L, Dai X, Liu Y, Sun J, Song S, Ni BJ. Model-based assessment of estrogen removal by nitrifying activated sludge. Chemosphere 2018; 197:430-437. [PMID: 29360597 DOI: 10.1016/j.chemosphere.2018.01.035] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/20/2017] [Revised: 01/02/2018] [Accepted: 01/10/2018] [Indexed: 06/07/2023]
Abstract
Complete removal of estrogens such as estrone (E1), estradiol (E2), estriol (E3) and ethinylestradiol (EE2) in wastewater treatment is essential since their release and accumulation in natural water bodies are giving rise to environment and health issues. To improve our understanding towards the estrogen bioremediation process, a mathematical model was proposed for describing estrogen removal by nitrifying activated sludge. Four pathways were involved in the developed model: i) biosorption by activated sludge flocs; ii) cometabolic biodegradation linked to ammonia oxidizing bacteria (AOB) growth; iii) non-growth biodegradation by AOB; and iv) biodegradation by heterotrophic bacteria (HB). The degradation kinetics was implemented into activated sludge model (ASM) framework with consideration of interactions between substrate update and microorganism growth as well as endogenous respiration. The model was calibrated and validated by fitting model predictions against two sets of batch experimental data under different conditions. The model could satisfactorily capture all the dynamics of nitrogen, organic matters (COD), and estrogens. Modeling results suggest that for E1, E2 and EE2, AOB-linked biodegradation is dominant over biodegradation by HB at all investigated COD dosing levels. However, for E3, the increase of COD dosage triggers a shift of dominant pathway from AOB biodegradation to HB biodegradation. Adsorption becomes the main contributor to estrogen removal at high biomass concentrations.
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Affiliation(s)
- Lai Peng
- School of Resources and Environmental Engineering, Wuhan University of Technology, Luoshi Road 122, Wuhan, Hubei, 430070, China; Research Group of Sustainable Energy, Air and Water Technology, Department of Bioscience Engineering, University of Antwerp, Groenenborgerlaan 171, 2020, Antwerpen, Belgium
| | - Xiaohu Dai
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai, 200092, PR China; Shanghai Institute of Pollution Control and Ecological Security, PR China
| | - Yiwen Liu
- Centre for Technology in Water and Wastewater, School of Civil and Environmental Engineering, University of Technology Sydney, Sydney, NSW, 2007, Australia; Water Chemistry and Water Technology, Engler-Bunte-Institut, Karlsruhe Institute of Technology, Karlsruhe, Germany
| | - Jing Sun
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai, 200092, PR China; Shanghai Institute of Pollution Control and Ecological Security, PR China
| | - Shaoxian Song
- School of Resources and Environmental Engineering, Wuhan University of Technology, Luoshi Road 122, Wuhan, Hubei, 430070, China
| | - Bing-Jie Ni
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai, 200092, PR China; Shanghai Institute of Pollution Control and Ecological Security, PR China.
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44
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Sudha Rani P, Sampath Kumar G, Mukherjee J, Srinivas TNR, Sarma VVSS. Perennial occurrence of heterotrophic, indicator and pathogenic bacteria in the coastal Bay of Bengal (off Visakhapatnam) - Impact of physical and atmospheric processes. Mar Pollut Bull 2018; 127:412-423. [PMID: 29475679 DOI: 10.1016/j.marpolbul.2017.12.023] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/19/2017] [Revised: 12/04/2017] [Accepted: 12/08/2017] [Indexed: 06/08/2023]
Abstract
In order to examine the health of the coastal waters off Visakhapatnam in terms of prevalence and abundance of heterotrophic (H), indicator and pathogenic (P) bacterial counts (BC) and influence of physical processes on them, time-series observations were conducted during January (winter), March (spring), July (summer) and October (post-monsoon). We noticed the impact of physical forces on substantial variations in abundance and distribution of the HBC, total coliforms, Enterococcus faecalis and Pseudomonas aeruginosa in the study region. Based on our results Escherichia coli and other PBC were not much influenced by the physical conditions. It has been noticed that the perennial existence of the high abundance of IBC and PBC above the standard limits during the entire study period leading to an alarming situation in the coastal waters off Visakhapatnam.
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Affiliation(s)
- P Sudha Rani
- CSIR-National Institute of Oceanography, Regional Centre, 176, Lawsons Bay Colony, Visakhapatnam 530 017, India
| | - G Sampath Kumar
- CSIR-National Institute of Oceanography, Regional Centre, 176, Lawsons Bay Colony, Visakhapatnam 530 017, India
| | - J Mukherjee
- CSIR-National Institute of Oceanography, Regional Centre, 176, Lawsons Bay Colony, Visakhapatnam 530 017, India
| | - T N R Srinivas
- CSIR-National Institute of Oceanography, Regional Centre, 176, Lawsons Bay Colony, Visakhapatnam 530 017, India.
| | - V V S S Sarma
- CSIR-National Institute of Oceanography, Regional Centre, 176, Lawsons Bay Colony, Visakhapatnam 530 017, India
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Li G, Liu J, Diao Z, Jiang X, Li J, Ke Z, Shen P, Ren L, Huang L, Tan Y. Subsurface low dissolved oxygen occurred at fresh- and saline-water intersection of the Pearl River estuary during the summer period. Mar Pollut Bull 2018; 126:585-591. [PMID: 28986111 DOI: 10.1016/j.marpolbul.2017.09.061] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/04/2017] [Revised: 09/26/2017] [Accepted: 09/26/2017] [Indexed: 06/07/2023]
Abstract
Estuarine oxygen depletion is one of the worldwide problems, which is caused by the freshwater-input-derived severe stratification and high nutrients loading. In this study we presented the horizontal and vertical distributions of dissolved oxygen (DO) in the Pearl River estuary, together with temperature, salinity, chlorophyll a concentration and heterotrophic bacteria abundance obtained from two cruises during the summer (wet) and winter (dry) periods of 2015. In surface water, the DO level in the summer period was lower and varied greater, as compared to the winter period. The DO remained unsaturated in the summer period if salinity is <12 and saturated if salinity is >12; while in the winter period it remained saturated throughout the estuary. In subsurface (>5m) water, the DO level varied from 0.71 to 6.65mgL-1 and from 6.58 to 8.20mgL-1 in the summer and winter periods, respectively. Particularly, we observed an area of ~1500km2 low DO zone in the subsurface water with a threshold of 4mgDOL-1 during this summer period, that located at the fresh- and saline-water intersection where is characterized with severe stratification and high heterotrophic bacteria abundance. In addition, our results indicate that spatial DO variability in surface water was contributed differently by biological and physio-chemical variables in the summer and winter periods, respectively.
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Affiliation(s)
- Gang Li
- Key Laboratory of Tropical Marine Bio-resources and Ecology & Guangdong Provincial Key Laboratory of Applied Marine Biology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China.
| | - Jiaxing Liu
- Key Laboratory of Tropical Marine Bio-resources and Ecology & Guangdong Provincial Key Laboratory of Applied Marine Biology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China
| | - Zenghui Diao
- Key Laboratory of Tropical Marine Bio-resources and Ecology & Guangdong Provincial Key Laboratory of Applied Marine Biology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China
| | - Xin Jiang
- Key Laboratory of Tropical Marine Bio-resources and Ecology & Guangdong Provincial Key Laboratory of Applied Marine Biology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China
| | - Jiajun Li
- Key Laboratory of Tropical Marine Bio-resources and Ecology & Guangdong Provincial Key Laboratory of Applied Marine Biology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China
| | - Zhixin Ke
- Key Laboratory of Tropical Marine Bio-resources and Ecology & Guangdong Provincial Key Laboratory of Applied Marine Biology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China
| | - Pingping Shen
- Key Laboratory of Tropical Marine Bio-resources and Ecology & Guangdong Provincial Key Laboratory of Applied Marine Biology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China
| | - Lijuan Ren
- Key Laboratory of Tropical Marine Bio-resources and Ecology & Guangdong Provincial Key Laboratory of Applied Marine Biology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China
| | - Liangmin Huang
- Key Laboratory of Tropical Marine Bio-resources and Ecology & Guangdong Provincial Key Laboratory of Applied Marine Biology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China
| | - Yehui Tan
- Key Laboratory of Tropical Marine Bio-resources and Ecology & Guangdong Provincial Key Laboratory of Applied Marine Biology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China.
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Wu J, Zhang Y. Evaluation of the impact of organic material on the anaerobic methane and ammonium removal in a membrane aerated biofilm reactor (MABR) based on the multispecies biofilm modeling. Environ Sci Pollut Res Int 2017; 24:1677-1685. [PMID: 27796976 DOI: 10.1007/s11356-016-7938-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/25/2016] [Accepted: 10/19/2016] [Indexed: 06/06/2023]
Abstract
The simultaneous nitrogen and methane removal by the combined nitritation, anaerobic ammonium oxidation (anammox), and nitrite dependent anaerobic methane oxidation (n-damo) processes in the membrane aerated biofilm reactor (MABR) offers clear advantages in term of energy saving and greenhouse gas emission mitigation. The rejected water from sludge digestion usually contained high ammonium, COD, and dissolved methane. The impact of influent COD on the anaerobic methane and ammonium removal in an MABR was evaluated in the model based study. The results indicated that the influent COD did not reduce the methane and ammonium removal efficiency at C/N ratio (influent COD/NH4+-N) less than 0.1. At high C/N ratio, the oxygen transfer coefficient needed to be increased to achieve high methane and nitrogen removal. Substrate flux analysis indicated that heterotrophic denitrification in the outside layer of biofilm reduced the impact of influent COD. Heterotrophic growth needed to be limited at the outside layer by using NO3- as electron acceptor; otherwise, the heterotrophic bacteria would compete NO2- and space with anammox and n-damo bacteria in the inner layers and reduce the nitrogen and methane removal efficiency.
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Affiliation(s)
- Jun Wu
- School of Environmental Engineering and Science, Yangzhou University, 196 West Huayang Road, Yangzhou, Jiangsu, 225127, China.
| | - Yue Zhang
- School of Environmental Engineering and Science, Yangzhou University, 196 West Huayang Road, Yangzhou, Jiangsu, 225127, China
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Gérikas Ribeiro C, Lopes Dos Santos A, Marie D, Helena Pellizari V, Pereira Brandini F, Vaulot D. Pico and nanoplankton abundance and carbon stocks along the Brazilian Bight. PeerJ 2016; 4:e2587. [PMID: 27867760 PMCID: PMC5111892 DOI: 10.7717/peerj.2587] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2016] [Accepted: 09/20/2016] [Indexed: 01/10/2023] Open
Abstract
Pico and nanoplankton communities from the Southwest Atlantic Ocean along the Brazilian Bight are poorly described. The hydrography in this region is dominated by a complex system of layered water masses, which includes the warm and oligotrophic Tropical Water (TW), the cold and nutrient rich South Atlantic Central Water (SACW) and the Coastal Water (CW), which have highly variable properties. In order to assess how pico- and nanoplankton communities are distributed in these different water masses, we determined by flow cytometry the abundance of heterotrophic bacteria, Prochlorococcus, Synechococcus and autotrophic pico and nanoeukaryotes along three transects, extending from 23°S to 31°S and 39°W to 49°W. Heterotrophic bacteria (including archaea, maximum of 1.5 × 106 cells mL−1) were most abundant in Coastal and Tropical Water whereas Prochlorococcus was most abundant in open-ocean oligotrophic waters (maximum of 300 × 103 cells mL−1). Synechococcus(up to 81 × 103 cells mL−1), as well as autotrophic pico and nanoeukaryotes seemed to benefit from the influx of nutrient-rich waters near the continental slope. Autotrophic pico and nanoeukaryotes were also abundant in deep chlorophyll maximum (DCM) layers from offshore waters, and their highest abundances were 20 × 103 cells mL−1 and 5 × 103 cells mL−1, respectively. These data are consistent with previous observations in other marine areas where Synechococcus and autotrophic eukaryotes dominate mesotrophic waters, whereas Prochlorococcus dominate in more oligotrophic areas. Regardless of the microbial community structure near the surface, the carbon stock dominance by autotrophic picoeukaryotes near the DCM is possibly linked to vertical mixing of oligotrophic surface waters with the nutrient-rich SACW and their tolerance to lower light levels.
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Affiliation(s)
- Catherine Gérikas Ribeiro
- Departamento de Oceanografia Biológica, Instituto Oceanográfico, Universidade de São Paulo , São Paulo , Brazil
| | - Adriana Lopes Dos Santos
- Sorbonne Universités, UPMC Université Paris 06, CNRS, UMR 7144 , Station Biologique de Roscoff , France
| | - Dominique Marie
- Sorbonne Universités, UPMC Université Paris 06, CNRS, UMR 7144 , Station Biologique de Roscoff , France
| | - Vivian Helena Pellizari
- Departamento de Oceanografia Biológica, Instituto Oceanográfico, Universidade de São Paulo , São Paulo , Brazil
| | - Frederico Pereira Brandini
- Departamento de Oceanografia Biológica, Instituto Oceanográfico, Universidade de São Paulo , São Paulo , Brazil
| | - Daniel Vaulot
- Sorbonne Universités, UPMC Université Paris 06, CNRS, UMR 7144 , Station Biologique de Roscoff , France
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SHAHRYARI A, NIKAEEN M, HATAMZADEH M, VAHID DASTJERDI M, HASSANZADEH A. Evaluation of Bacteriological and Chemical Quality of Dialysis Water and Fluid in Isfahan, Central Iran. Iran J Public Health 2016; 45:650-6. [PMID: 27398338 PMCID: PMC4935709] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND Chemical and microbial quality of water used in hemodialysis play key roles in a number of dialysis-related complications. In order to avoid the complications and to guarantee safety and health of patients therefore, vigorous control of water quality is essential. The objective of present study was to investigate the chemical and bacteriological characteristics of water used in dialysis centers of five hospitals in Isfahan, central Iran. METHODS A total of 30 water samples from the input of dialysis purification system and dialysis water were analyzed for chemical parameters. Heterotrophic plate count and endotoxin concentration of drinking water, dialysis water and dialysis fluid of 40 machines were also monitored over a 5-month period in 2011-2012. RESULTS Concentration of the determined chemicals (copper, zinc, sulfate, fluoride, chloramines and free chlorine) did not exceed the recommended concentration by the Association for the Advancement of Medical Instrumentation (AAMI) exclude lead, nitrate, aluminum and calcium. Furthermore, the magnesium; cadmium and chromium concentration exceeded the maximum level in some centers. No contamination with heterotrophic bacteria was observed in all samples, while the AMMI standard for endotoxin level in dialysis fluid (<2 EU/ml) was achieved in 95% of samples. CONCLUSION Dialysis water and fluid failed to meet the all chemical and bacteriological requirements for hemodialysis. To minimize the risk of contaminants for hemodialysis patients therefore, a water quality management program including monitoring, maintenance and development of water treatment system in hemodialysis centers is extremely important. In addition, an appropriate disinfection program is needed to guarantee better control of bacterial growth and biofilm formation.
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Affiliation(s)
- Ali SHAHRYARI
- Dept. of Environmental Health Engineering, School of Health, Golestan University of Medical Sciences, Gorgan, Iran
| | - Mahnaz NIKAEEN
- Dept. of Environmental Health Engineering, School of Health, Isfahan University of Medical Sciences, Isfahan, Iran,Corresponding Author:
| | - Maryam HATAMZADEH
- Dept. of Environmental Health Engineering, School of Health, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Marzieh VAHID DASTJERDI
- Dept. of Environmental Health Engineering, School of Health, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Akbar HASSANZADEH
- Dept. of Statistics and Epidemiology, School of Health, Isfahan University of Medical Sciences, Isfahan, Iran
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Makowska N, Koczura R, Mokracka J. Class 1 integrase, sulfonamide and tetracycline resistance genes in wastewater treatment plant and surface water. Chemosphere 2016; 144:1665-73. [PMID: 26519797 DOI: 10.1016/j.chemosphere.2015.10.044] [Citation(s) in RCA: 129] [Impact Index Per Article: 16.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/17/2015] [Revised: 10/06/2015] [Accepted: 10/10/2015] [Indexed: 05/08/2023]
Abstract
Wastewater treatment plants are considered hot spots for multiplication and dissemination of antibiotic-resistant bacteria and resistance genes. In this study, we determined the presence of class 1 integron integrase and genes conferring resistance to tetracyclines and sulfonamides in the genomes of culturable bacteria isolated from a wastewater treatment plant and the river that receives the treated wastewater. Moreover, using PCR-based metagenomic approach, we quantified intI1, tet and sul genes. Wastewater treatment caused the decrease in the total number of culturable heterotrophs and bacteria resistant to tetracycline and sulfonamides, along with the decrease in the number of intI1, sul and tet gene copies per ml, with significant reduction of tet(B). On the other hand, the treatment process increased both the frequency of tetracycline- and sulfonamide-resistant bacteria and intI1-positive strains, and the relative abundance of all quantified antibiotic resistance genes (ARGs) and intI1 gene; in the case of tet(A) and sul2 significantly. The discharge of treated wastewater increased the number of intI1, tet and sul genes in the receiving river water both in terms of copy number per ml and relative abundance. Hence, despite the reduction of the number of ARGs and ARBs, wastewater treatment selects for bacteria with ARGs in effluent.
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Affiliation(s)
- Nicoletta Makowska
- Department of Microbiology, Faculty of Biology, Adam Mickiewicz University in Poznań, Umultowska 89, 61-614 Poznań, Poland
| | - Ryszard Koczura
- Department of Microbiology, Faculty of Biology, Adam Mickiewicz University in Poznań, Umultowska 89, 61-614 Poznań, Poland
| | - Joanna Mokracka
- Department of Microbiology, Faculty of Biology, Adam Mickiewicz University in Poznań, Umultowska 89, 61-614 Poznań, Poland.
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50
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AMANIDAZ N, ZAFARZADEH A, MAHVI AH. The Interaction between Heterotrophic Bacteria and Coliform, Fecal Coliform, Fecal Streptococci Bacteria in the Water Supply Networks. Iran J Public Health 2015; 44:1685-92. [PMID: 26811820 PMCID: PMC4724742] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 10/29/2022]
Abstract
BACKGROUND This study investigated the interaction between heterotrophic bacteria and coliform, fecal coliforms, fecal streptococci bacteria in water supply networks. METHODS This study was conducted during 2013 on water supply distribution network in Aq Qala City, Golestan Province, Northern Iran and standard methods were applied for microbiological analysis. The surface method was applied to test the heterotrophic bacteria and MPN method was used for coliform, fecal coliform and fecal streptococci bacteria measurements. RESULTS In 114 samples, heterotrophic bacteria count were over 500 CFU/ml, which the amount of fecal coliform, coliform, and fecal streptococci were 8, 32, and 20 CFU/100 ml, respectively. However, in the other 242 samples, with heterotrophic bacteria count being less than 500 CFU/ml, the amount of fecal coliform, coliform, and fecal streptococci was 7, 23, and 11 CFU/100ml, respectively. The relationship between heterotrophic bacteria, coliforms and fecal streptococci was highly significant (P<0.05). We observed the concentration of coliforms, fecal streptococci bacteria being high, whenever the concentration of heterotrophic bacteria in the water network systems was high. CONCLUSION Interaction between heterotrophic bacteria and coliform, fecal coliforms, fecal streptococci bacteria in the Aq Qala City water supply networks was not notable. It can be due to high concentrations of organic carbon, bio-films and nutrients, which are necessary for growth, and survival of all microorganisms.
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Affiliation(s)
- Nazak AMANIDAZ
- Dept. of Environmental Health Engineering, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
| | - Ali ZAFARZADEH
- Research Center for Environmental Health, Department of Environmental Health Engineering, School of Public Health, Golestan University of Medical Sciences, Gorgan, Iran
| | - Amir Hossein MAHVI
- Dept. of Environmental Health Engineering, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran,Center for Solid Waste Research, Institute for Environmental Research, Tehran University of Medical Sciences, Tehran, Iran,Corresponding Author:
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