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Tsilo PH, Basson AK, Ntombela ZG, Dlamini NG, Pullabhotla RVSR. Application of Iron Nanoparticles Synthesized from a Bioflocculant Produced by Yeast Strain Pichia kudriavzevii Obtained from Kombucha Tea SCOBY in the Treatment of Wastewater. Int J Mol Sci 2023; 24:14731. [PMID: 37834177 PMCID: PMC10572716 DOI: 10.3390/ijms241914731] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2023] [Revised: 09/20/2023] [Accepted: 09/23/2023] [Indexed: 10/15/2023] Open
Abstract
Studying the production of Iron (Fe) nanoparticles using natural substances is an intriguing area of research in nanotechnology, as these nanoparticles possess biocompatibility and natural stability, which make them useful for a variety of industrial applications. The study utilized Fe nanoparticles that were synthesized using a bioflocculant and applied to eliminate different kinds of pollutants and dyes found in wastewater and solutions. The study involved the generation of Fe nanoparticles through a bioflocculant obtained from Pichia kudriavzevii, which were evaluated for their flocculation and antimicrobial capabilities. The impact of the Fe nanoparticles on human embryonic kidney (HEK 293) cell lines was studied to assess their potential cytotoxicity effects. An array of spectroscopic and microscopic methods was employed to characterize the biosynthesized Fe nanoparticles, including SEM-EDX, FT-IR, TEM, XRD, UV-vis, and TGA. A highly efficient flocculating activity of 85% was achieved with 0.6 mg/mL dosage of Fe nanoparticles. The biosynthesized Fe nanoparticles demonstrated a noteworthy concentration-dependent cytotoxicity effect on HEK 293 cell lines with the highest concentration used resulting in 34% cell survival. The Fe nanoparticles exhibited strong antimicrobial properties against a variety of evaluated Gram-positive and Gram-negative microorganisms. The efficiency of removing dyes by the nanoparticles was found to be higher than 65% for the tested dyes, with the highest being 93% for safranine. The Fe nanoparticles demonstrated remarkable efficiency in removing various pollutants from wastewater. In comparison to traditional flocculants and the bioflocculant, biosynthesized Fe nanoparticles possess significant potential for eliminating both biological oxygen demand (BOD) and chemical oxygen demand (COD) from wastewater samples treated. Hence, the Fe nanoparticles synthesized in this way have the potential to substitute chemical flocculants in the treatment of wastewater.
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Affiliation(s)
- Phakamani H. Tsilo
- Department of Biochemistry and Microbiology, Faculty of Science, Agriculture, and Engineering, University of Zululand, Private Bag X1001, Kwadlangezwa 3886, South Africa; (P.H.T.); (A.K.B.); (Z.G.N.); (N.G.D.)
| | - Albertus K. Basson
- Department of Biochemistry and Microbiology, Faculty of Science, Agriculture, and Engineering, University of Zululand, Private Bag X1001, Kwadlangezwa 3886, South Africa; (P.H.T.); (A.K.B.); (Z.G.N.); (N.G.D.)
| | - Zuzingcebo G. Ntombela
- Department of Biochemistry and Microbiology, Faculty of Science, Agriculture, and Engineering, University of Zululand, Private Bag X1001, Kwadlangezwa 3886, South Africa; (P.H.T.); (A.K.B.); (Z.G.N.); (N.G.D.)
| | - Nkosinathi G. Dlamini
- Department of Biochemistry and Microbiology, Faculty of Science, Agriculture, and Engineering, University of Zululand, Private Bag X1001, Kwadlangezwa 3886, South Africa; (P.H.T.); (A.K.B.); (Z.G.N.); (N.G.D.)
| | - Rajasekhar V. S. R. Pullabhotla
- Department of Chemistry, Faculty Science, Agriculture, and Engineering, University of Zululand, Private Bag X1001, Kwadlangezwa 3886, South Africa
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Bioflocculant produced by Bacillus velezensis and its potential application in brewery wastewater treatment. Sci Rep 2022; 12:10945. [PMID: 35768624 PMCID: PMC9243052 DOI: 10.1038/s41598-022-15193-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2022] [Accepted: 04/15/2022] [Indexed: 12/04/2022] Open
Abstract
This study was designed to evaluate the potential of bioflocculant producing strains isolated from wastewater sludge. According to the Plackett–Burman design, the response surface revealed glucose, magnesium sulfate, and ammonium sulfate as critical media components of the nutritional source, whereas the central composite design affirmed an optimum concentration of the critical nutritional source as 16.0 g/l (glucose), 3.5 g/l magnesium sulfate heptahydrate (MgSO4.7H2O), and 1.6 g/l ammonium sulfate ( (NH4)2SO4), yielding an optimal flocculation activity of 96.8%. Fourier Transformer Infrared Spectroscopy (FTIR) analysis confirmed the presence of hydroxyl, carboxyl and methoxyl in the structure of the bioflocculant. Additionally, chemical analysis affirmed the presence of mainly a polysaccharide in the main backbone of the purified bioflocculant with no detection of protein. Energy Dispersive X-ray analysis affirmed the presence of chlorine, phosphorous, oxygen and chlorine as representatives of elemental composition. Thermogravimetric (TGA) analysis revealed over 60% weight was retained at a temperature range of 700 °C. The purified bioflocculant remarkably removed chemical oxygen demand, biological oxygen demand and turbidity in brewery wastewater. This study suggested that the bioflocculant might be an alternate candidate for wastewater treatment.
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Feng J, Xu Y, Ding J, He J, Shen Y, Lu G, Qin W, Guo H. Optimal production of bioflocculant from Pseudomonas sp. GO2 and its removal characteristics of heavy metals. J Biotechnol 2022; 344:50-56. [PMID: 34973970 DOI: 10.1016/j.jbiotec.2021.12.012] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2021] [Revised: 12/22/2021] [Accepted: 12/23/2021] [Indexed: 10/19/2022]
Abstract
Bioflocculant may be a promising bioactivator for heavy metal removal duo to its eco-friendly properties and remarkable ability to adsorb heavy metals. In this study, bioflocculant production from a bacterium, Pseudomonas sp. GO2, was optimized and its removal efficiency for two heavy metal ions was evaluated. Results demonstrated that the maximal flocculation efficiency was achieved with concentration levels of 5 g/L glucose, 3 g/L casein, and 5 g/L NaCl, with an initial pH of 9.0, and a fermentation time of 48 h. Bioflocculant produced by GO2 had a stronger removal efficiency for Cd2+ than that of Pb2+, with highest removal efficiencies of 85.38% and 80.87%, respectively. The adsorption process was mainly dependent on the monolayer and chemisorption based on the adsorption isotherm and kinetic models. This study demonstrated that bioflocculant produced by the GO2 strain has the potential to be used in heavy metal treatment from industrial wastewater.
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Affiliation(s)
- Jiayin Feng
- State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-Products, Ningbo University, Ningbo 315211, China; School of Marine Sciences, Ningbo University, Ningbo 315211, China
| | - Yijie Xu
- State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-Products, Ningbo University, Ningbo 315211, China; School of Marine Sciences, Ningbo University, Ningbo 315211, China
| | - Jianhui Ding
- State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-Products, Ningbo University, Ningbo 315211, China; School of Marine Sciences, Ningbo University, Ningbo 315211, China
| | - Jikun He
- State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-Products, Ningbo University, Ningbo 315211, China; School of Marine Sciences, Ningbo University, Ningbo 315211, China
| | - Yihan Shen
- State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-Products, Ningbo University, Ningbo 315211, China; School of Marine Sciences, Ningbo University, Ningbo 315211, China
| | - Guimeng Lu
- State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-Products, Ningbo University, Ningbo 315211, China; School of Marine Sciences, Ningbo University, Ningbo 315211, China
| | - Wensheng Qin
- Department of Biology, Lakehead University, Ontario P7B 5E1, Canada
| | - Haipeng Guo
- State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-Products, Ningbo University, Ningbo 315211, China; School of Marine Sciences, Ningbo University, Ningbo 315211, China.
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Rajivgandhi G, Vimala RTV, Maruthupandy M, Alharbi NS, Kadaikunnan S, Khaled JM, Manoharan N, Li WJ. Enlightening the characteristics of bioflocculant of endophytic actinomycetes from marine algae and its biosorption of heavy metal removal. ENVIRONMENTAL RESEARCH 2021; 200:111708. [PMID: 34280417 DOI: 10.1016/j.envres.2021.111708] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/20/2021] [Revised: 07/10/2021] [Accepted: 07/13/2021] [Indexed: 06/13/2023]
Abstract
The removal of toxic heavy metal ions from contaminated environments is a great challenge and requires an alternative rapid, efficient, economical bioremediation approach. Henceforth, bioflocculant producing endophytic actinobacterial sp. was isolated from heavy metal contaminated marine environments for heavy metal biosorption process. After molecular characterization, the isolated actinomycete starin was Nocardiopsis sp. GRG 3 (KT235642). It was indicated that the maximum flocculating activity of 80.90% with glucose, and yield is 4.52 g L1. The optimum flocculating activity was reached at pH 7 in the presence of CaCl2 ions. Further, the bioflocculent produced Nocardiopsis sp. GRG 3 (KT235642) was characterized by fourier transform infrared analysis spectra (FTIR) and displayed the presence of carboxyl, hydroxyl, amino groups and characteristic of more polysaccharide and protein. The heavy metal sorption by bioflocculant Nocardiopsis sp. GRG 3 (KT235642) was effectively removed 55.90% Cd, 85.90% Cr, 74.7% Pb, and 51.90% Hg. Therefore, this study was proved that the bioflocculant derived from endophytic actinobacteria, Nocardiopsis sp. GRG 3 (KT235642) as a effective alternative method for decreasing the heavy metals towards sustainable environmental management.
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Affiliation(s)
- Govindan Rajivgandhi
- State Key Laboratory of Biocontrol, Guangdong Provincial Key Laboratory of Plant Resources and Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), School of Life Sciences, Sun Yat-Sen University, Guangzhou, 510275, PR China; Department of Marine Science, Bharathidasan University, Tiruchirappalli, 620024, Tamil Nadu, India
| | - R T V Vimala
- Department of Biotechnology, Bharathidasan University, Tiruchirappalli, 620024, India.
| | - Muthuchamy Maruthupandy
- Lab of Toxicology, Department of Health Sciences, The Graduate School of Dong-A University, 37, Nakdong-Dearo 550 Beon-Gil, Saha-Gu Busan, 49315, South Korea
| | - Naiyf S Alharbi
- Department of Botany and Microbiology, College of Science, King Saud University, Riyadh, 11451, Saudi Arabia
| | - Shine Kadaikunnan
- Department of Botany and Microbiology, College of Science, King Saud University, Riyadh, 11451, Saudi Arabia
| | - Jamal M Khaled
- Department of Botany and Microbiology, College of Science, King Saud University, Riyadh, 11451, Saudi Arabia
| | - Natesan Manoharan
- Department of Marine Science, Bharathidasan University, Tiruchirappalli, 620024, Tamil Nadu, India.
| | - Wen-Jun Li
- State Key Laboratory of Biocontrol, Guangdong Provincial Key Laboratory of Plant Resources and Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), School of Life Sciences, Sun Yat-Sen University, Guangzhou, 510275, PR China; State Key Laboratory of Desert and Oasis Ecology, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi, 830011, PR China.
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Liu C, Sun D, Liu J, Zhu J, Liu W. Recent advances and perspectives in efforts to reduce the production and application cost of microbial flocculants. BIORESOUR BIOPROCESS 2021; 8:51. [PMID: 38650196 PMCID: PMC10992557 DOI: 10.1186/s40643-021-00405-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2021] [Accepted: 06/08/2021] [Indexed: 01/09/2023] Open
Abstract
Microbial flocculants are macromolecular substances produced by microorganisms. Due to its non-toxic, harmless, and biodegradable advantages, microbial flocculants have been widely used in various industrial fields, such as wastewater treatment, microalgae harvest, activated sludge dewatering, heavy metal ion adsorption, and nanoparticle synthesis, especially in the post-treatment process of fermentation with high safety requirement. However, compared with the traditional inorganic flocculants and organic polymeric flocculants, the high production cost is the main bottleneck that restricts the large-scale production and application of microbial flocculants. To reduce the production cost of microbial flocculant, a series of efforts have been carried out and some exciting research progresses have been achieved. This paper summarized the research advances in the last decade, including the screening of high-yield strains and the construction of genetically engineered strains, search of cheap alternative medium, the extraction and preservation methods, microbial flocculants production as an incidental product of other biological processes, combined use of traditional flocculant and microbial flocculant, and the production of microbial flocculant promoted by inducer. Moreover, this paper prospects the future research directions to further reduce the production cost of microbial flocculants, thereby promoting the industrial production and large-scale application of microbial flocculants.
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Affiliation(s)
- Cong Liu
- Jiangsu Key Laboratory of Phylogenomics & Comparative Genomics, School of Life Science, Jiangsu Normal University, No.101, Shanghai road, Tongshan New District, Xuzhou, 221116, Jiangsu, China
| | - Di Sun
- Jiangsu Key Laboratory of Phylogenomics & Comparative Genomics, School of Life Science, Jiangsu Normal University, No.101, Shanghai road, Tongshan New District, Xuzhou, 221116, Jiangsu, China
| | - Jiawen Liu
- Jiangsu Key Laboratory of Phylogenomics & Comparative Genomics, School of Life Science, Jiangsu Normal University, No.101, Shanghai road, Tongshan New District, Xuzhou, 221116, Jiangsu, China
| | - Jingrong Zhu
- Jiangsu Key Laboratory of Phylogenomics & Comparative Genomics, School of Life Science, Jiangsu Normal University, No.101, Shanghai road, Tongshan New District, Xuzhou, 221116, Jiangsu, China
| | - Weijie Liu
- Jiangsu Key Laboratory of Phylogenomics & Comparative Genomics, School of Life Science, Jiangsu Normal University, No.101, Shanghai road, Tongshan New District, Xuzhou, 221116, Jiangsu, China.
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Okaiyeto K, Ekundayo TC, Okoh AI. Global research trends on bioflocculant potentials in wastewater remediation from 1990 to 2019 using a bibliometric approach. Lett Appl Microbiol 2020; 71:567-579. [PMID: 32780872 DOI: 10.1111/lam.13361] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2020] [Revised: 07/15/2020] [Accepted: 07/16/2020] [Indexed: 12/17/2022]
Abstract
The preference of biofloculants over chemical flocculants in water and wastewater remediation systems has gained wider attention due to their biodegradability, innocuousness, safety to human and environmental friendliness. The present study aimed to evaluate research outputs on bioflocculant potentials in wastewater remediation from 1990 to 2019 using bibliometric analyses. To the best of our knowledge, this is the first bibliometric report in bioflocculant research. The subject bibliometric dataset was extracted from the Web of Science Core Collection (WoSCC) and Scopus using the Boolean, 'bioflocculant* and waste*' and analysed for indicators such as a yearly trend, productivity (authors, articles, country, institution and journal source), conceptual framework and collaboration network. We found 119 documents with 347 authors from 78 journal sources on the subject, an annual growth rate of 12·1%, and average citations/document of 15·08. Guo J. and Wang Y. were the top researchers with 15 and 12 outputs respectively. China (42%) and South Africa (9·24%) ranked the top two dominant countries in the field. The top journals were Bioresource Technology (9 papers, 506 citations), Applied Microbiology and Biotechnology (5 papers, 268 citations), whereas, the top institution was Chengdu University of Information and Technology (n = 9 documents) followed by Sichuan Univ. Sci. & Engn, China (n = 8 documents). This study found that lack of intercountry collaboration and research funding adversely affects research participants in the field.
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Affiliation(s)
- K Okaiyeto
- SAMRC, Microbial Water Quality Monitoring Centre, University of Fort Hare, Eastern Cape, Alice, South Africa.,Applied and Environmental Microbiology Research Group (AEMREG), Department of Biochemistry and Microbiology, University of Fort Hare, Eastern Cape, South Africa
| | - T C Ekundayo
- SAMRC, Microbial Water Quality Monitoring Centre, University of Fort Hare, Eastern Cape, Alice, South Africa.,Applied and Environmental Microbiology Research Group (AEMREG), Department of Biochemistry and Microbiology, University of Fort Hare, Eastern Cape, South Africa.,Department of Biological Sciences, University of Medical Sciences, Ondo City, Nigeria
| | - A I Okoh
- SAMRC, Microbial Water Quality Monitoring Centre, University of Fort Hare, Eastern Cape, Alice, South Africa.,Applied and Environmental Microbiology Research Group (AEMREG), Department of Biochemistry and Microbiology, University of Fort Hare, Eastern Cape, South Africa
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Patel G, Khobragade TP, Avaghade SR, Patil MD, Nile SH, Kai G, Banerjee UC. Optimization of media and culture conditions for the production of tacrolimus by Streptomyces tsukubaensis in shake flask and fermenter level. BIOCATALYSIS AND AGRICULTURAL BIOTECHNOLOGY 2020. [DOI: 10.1016/j.bcab.2020.101803] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
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Hassimi AH, Ezril Hafiz R, Muhamad MH, Sheikh Abdullah SR. Bioflocculant production using palm oil mill and sago mill effluent as a fermentation feedstock: Characterization and mechanism of flocculation. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2020; 260:110046. [PMID: 32090804 DOI: 10.1016/j.jenvman.2019.110046] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/10/2019] [Revised: 12/26/2019] [Accepted: 12/27/2019] [Indexed: 06/10/2023]
Abstract
This study was conducted to examine the production of bioflocculants using agricultural wastewater as a fermentation feedstock under different temperatures and incubation times. The mechanism of flocculation was studied to gain a detailed understanding of the flocculation activity. The highest bioflocculant yield (2.03 g/L) at a temperature of 40 °C was produced in a palm oil mill effluent medium (BioF-POME). Bioflocculant produced from a fermented SME medium (BioF-SME) showed the highest activity. The flocculation tests for colour and turbidity removal from lake water indicated that BioF-SME and BioF-POME performed comparably to commercial alum. Analyses of the bioflocculants using liquid chromatography-mass spectrometry (LC-MS) found that the bioflocculants contained xylose and glucose. The mechanism study showed that flocculation occurred through charge neutralization and interparticle bridging between the bioflocculant polymer and the particles in the lake water. Thus, agricultural wastewater can be used as a fermentation feedstock for high-quality bioflocculants.
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Affiliation(s)
- Abu Hasan Hassimi
- Department of Chemical and Process Engineering, Faculty of Engineering and Built Environment, Universiti Kebangsaan Malaysia, 43600, UKM Bangi, Selangor, Malaysia.
| | - Razali Ezril Hafiz
- Department of Chemical and Process Engineering, Faculty of Engineering and Built Environment, Universiti Kebangsaan Malaysia, 43600, UKM Bangi, Selangor, Malaysia
| | - Mohd Hafizuddin Muhamad
- Department of Chemical and Process Engineering, Faculty of Engineering and Built Environment, Universiti Kebangsaan Malaysia, 43600, UKM Bangi, Selangor, Malaysia
| | - Siti Rozaimah Sheikh Abdullah
- Department of Chemical and Process Engineering, Faculty of Engineering and Built Environment, Universiti Kebangsaan Malaysia, 43600, UKM Bangi, Selangor, Malaysia
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Jingshen D, Quanjun L. Research on the coagulant aid effects of modified diatomite on coal microbial flocculation. WATER SCIENCE AND TECHNOLOGY : A JOURNAL OF THE INTERNATIONAL ASSOCIATION ON WATER POLLUTION RESEARCH 2019; 80:1893-1901. [PMID: 32144221 DOI: 10.2166/wst.2020.009] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Diatomite was modified by chitosan to prepare modified diatomite, and the modified diatomite in an optimized ratio was utilized in coal bio-flocculation. The interaction behavior and flocculation mechanism of modified diatomite on coal slurry water were investigated by single factor experiments, infrared spectroscopy, Brunauer-Emmett-Teller (BET) measurements, and zeta potential measurements. The single factor experiments showed that when the amount of microbial flocculant added was 1.5 ml, the temperature of coal slurry water was 39 °C, the pH was 5, and the amount of modified diatomite was 0.2 g, after 30 min of sedimentation, the flocculation transmittance of the coal slurry water reached 84.3%. The infrared spectra showed that the -NH2 and -OH of the chitosan molecule had a polar interaction with the Si-OH bond in diatomite. The BET measurements showed that the specific surface area of diatomite was not a decisive factor affecting the flocculation effect. Zeta potential measurements indicated that the amino protonation of chitosan increased the isoelectric point (IEP) of modified diatomite. These results showed that modified diatomite has a good effect on coal bio-flocculation.
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Production and Flocculating Performance of Bioflocculant by Bacterial Strain and its Application for Municipal Wastewater Treatment. JOURNAL OF PURE AND APPLIED MICROBIOLOGY 2019. [DOI: 10.22207/jpam.13.3.41] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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Ayangbenro AS, Babalola OO, Aremu OS. Bioflocculant production and heavy metal sorption by metal resistant bacterial isolates from gold mining soil. CHEMOSPHERE 2019; 231:113-120. [PMID: 31128345 DOI: 10.1016/j.chemosphere.2019.05.092] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/11/2018] [Revised: 05/06/2019] [Accepted: 05/12/2019] [Indexed: 06/09/2023]
Abstract
Two bioflocculant producing bacterial isolates from mining soil samples were investigated for their application in heavy metal removal. The bacterial isolates were identified as Pseudomonas koreensis and Pantoea sp. using 16S rRNA gene. Cadmium resistant genes cadA and CzcD were detected in Pantoea sp. while P. koreensis harbor CzcD and chrA responsible for Cd and Cr resistance respectively. The isolates showed maximum flocculating activity of 71.3% and 51.7% with glucose and yield of 2.98 g L-1 and 3.26 g L-1 for Pantoea sp. and P. koreensis respectively. The optimum flocculating activity was achieved at pH 7.5 and temperature of 30 °C. Fourier transform infrared analysis of the bioflocculants produced by the two isolates showed the presence of carboxyl, hydroxyl and amino groups characteristic of polysaccharide and protein. Heavy metal sorption by bioflocculant of Pantoea sp. removed 51.2% Cd, 52.5% Cr and 80.5% Pb while that of P. koreensis removed 48.5% Cd, 42.5% Cr and 73.7% Pb. The bioflocculants produced have potential in metal removal from industrial wastes.
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Affiliation(s)
- Ayansina Segun Ayangbenro
- Food Security and Safety Niche,Faculty of Natural and Agricultural Sciences, North-West University, Private Bag X2046, Mmabatho, 2735, South Africa
| | - Olubukola Oluranti Babalola
- Food Security and Safety Niche,Faculty of Natural and Agricultural Sciences, North-West University, Private Bag X2046, Mmabatho, 2735, South Africa.
| | - Oluwole Samuel Aremu
- Department of Chemistry, Faculty of Natural and Agricultural Sciences, North-West University, Private Bag X2046, Mmabatho 2735, South Africa
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Bisht V, Lal B. Exploration of Performance Kinetics and Mechanism of Action of a Potential Novel Bioflocculant BF-VB2 on Clay and Dye Wastewater Flocculation. Front Microbiol 2019; 10:1288. [PMID: 31231353 PMCID: PMC6568053 DOI: 10.3389/fmicb.2019.01288] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2019] [Accepted: 05/23/2019] [Indexed: 11/27/2022] Open
Abstract
This study explores production of an efficient bioflocculant; BF-VB2, by strain Bacillus sp. TERI VB2 and proposes its potential application in wastewater treatment. One milligram of BF-VB2 can effectively flocculate 1980.0 mg ± 5.0 mg of kaolin particles leading to 99.0% ± 0.5% enhancement in flocculation activity and 99.6% ± 1.0% reduction in turbidity; in less time. BF-VB2 when applied for treatment of textile dyeing industrial wastewater revealed reduction in dye color (82.78% ± 3.03%), COD (92.54% ± 0.24%), TSS (73.59% ± 0.71%), and chloride ions (81.90% ± 0.716%). The best-fit kinetic model (for both COD removal, and dye decolorization) was pseudo-first order with regression coefficient of 0.98 and 0.95, and rate constant of 4.33 × 10-2 and 1.83 × 102, respectively. Bridging due to presence of surface charges have been proposed as flocculation mechanism. From results obtained during test-tube studies, flocculation in larger volumes (0.01–5.0 L) was also performed to intend taking up BF-VB2 for in situ industrial wastewater treatment. This eco-friendly polysaccharide bioflocculant had longer shelf-life, stability to pH and temperature, cation-independence, and emerged to be more efficient than other flocculants assessed. This study proposed BF-VB2 as a potential natural flocculant candidate for industrial application.
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Affiliation(s)
- Varsha Bisht
- Department of Biotechnology, TERI School of Advanced Studies, New Delhi, India.,Environmental and Industrial Biotechnology Division, The Energy and Resources Institute, India Habitat Center, New Delhi, India
| | - Banwari Lal
- Environmental and Industrial Biotechnology Division, The Energy and Resources Institute, India Habitat Center, New Delhi, India
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Yang Z, Liu S, Zhang W, Wen Q, Guo Y. Enhancement of coal waste slurry flocculation by CTAB combined with bioflocculant produced by Azotobacter chroococcum. Sep Purif Technol 2019. [DOI: 10.1016/j.seppur.2018.10.036] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Microbial Flocculants as an Alternative to Synthetic Polymers for Wastewater Treatment: A Review. Symmetry (Basel) 2018. [DOI: 10.3390/sym10110556] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Microorganisms such as bacteria, fungi, and microalgae have been used to produce bioflocculants with various structures. These polymers are active substances that are biodegradable, environmentally harmless, and have flocculation characteristics. Most of the developed microbial bioflocculants displayed significant flocculating activity (FA > 70–90%) depending on the strain used and on the operating parameters. These biopolymers have been investigated and successfully used for wastewater depollution in the laboratory. In various cases, selected efficient microbial flocculants could reduce significantly suspended solids (SS), turbidity, chemical oxygen demand (COD), total nitrogen (Nt), dye, and heavy metals, with removal percentages exceeding 90% depending on the bioflocculating materials and on the wastewater characteristics. Moreover, bioflocculants showed acceptable results for sludge conditioning (accepted levels of dry solids, specific resistance to filtration, moisture, etc.) compared to chemicals. This paper explores various bioflocculants produced by numerous microbial strains. Their production procedures and flocculating performance will be included. Furthermore, their efficiency in the depollution of wastewater will be discussed.
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Guo H, Hong C, Zhang C, Zheng B, Jiang D, Qin W. Bioflocculants' production from a cellulase-free xylanase-producing Pseudomonas boreopolis G22 by degrading biomass and its application in cost-effective harvest of microalgae. BIORESOURCE TECHNOLOGY 2018; 255:171-179. [PMID: 29414164 DOI: 10.1016/j.biortech.2018.01.082] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/04/2017] [Revised: 01/15/2018] [Accepted: 01/17/2018] [Indexed: 06/08/2023]
Abstract
The major problem for industrial application of bioflocculants is its high production cost. Here, a novel bacterium Pseudomonas boreopolis G22, which can secret a cellulase-free xylanase and simultaneously produce bioflocculants (MBF-G22) through directly converting untreated biomass, was isolated. The bioflocculants' production of G22 was closely related to its xylanase activity, hydrolysis ability of biomass and the hemicellulose loss caused by G22. The optimal fermentation conditions with the highest bioflocculants' yield (3.75 mg g-1 dry biomass) were obtained at the fermentation time of 96 h, incubation temperature of 30 °C, inoculum concentration of 1.0% and biomass concentration of 1.0% in an initial pH value of 7.0. MBF-G22 mainly consisted of polysaccharides (63.3%) with a molecular weight of 3.982 × 106 Da and showed the highest flocculating efficiency of 97.1% at a dosage of 3.5 mg L-1. In addition, MBF-G22 showed high flocculating efficiency of microalgae (95.7%) at a dosage of 80 mg L-1.
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Affiliation(s)
- Haipeng Guo
- School of Marine Sciences, Ningbo University, Ningbo 315211, China; Department of Biology, Lakehead University, Thunder Bay, ON P7B 5E1, Canada; State Key Laboratory of Plant Physiology and Biochemistry, College of Life Sciences, Zhejiang University, Hangzhou 310058, China.
| | - Chuntao Hong
- Academy of Agricultural Sciences of Ningbo City, Ningbo 315040, China
| | - Cheng Zhang
- State Key Laboratory of Plant Physiology and Biochemistry, College of Life Sciences, Zhejiang University, Hangzhou 310058, China
| | - Bingsong Zheng
- State Key Laboratory of Subtropical Silviculture, Zhejiang A & F University, Hangzhou 311300, China
| | - Dean Jiang
- State Key Laboratory of Plant Physiology and Biochemistry, College of Life Sciences, Zhejiang University, Hangzhou 310058, China
| | - Wensheng Qin
- Department of Biology, Lakehead University, Thunder Bay, ON P7B 5E1, Canada.
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16
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Srivastava A, Seo SH, Ko SR, Ahn CY, Oh HM. Bioflocculation in natural and engineered systems: current perspectives. Crit Rev Biotechnol 2018; 38:1176-1194. [DOI: 10.1080/07388551.2018.1451984] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Affiliation(s)
- Ankita Srivastava
- Cell Factory Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon, Republic of Korea
| | - Seong-Hyun Seo
- Cell Factory Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon, Republic of Korea
| | - So-Ra Ko
- Cell Factory Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon, Republic of Korea
| | - Chi-Yong Ahn
- Cell Factory Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon, Republic of Korea
| | - Hee-Mock Oh
- Cell Factory Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon, Republic of Korea
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17
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Li Y, Xu Y, Zheng T, Wang H. Flocculation mechanism of the actinomycete Streptomyces sp. hsn06 on Chlorella vulgaris. BIORESOURCE TECHNOLOGY 2017; 239:137-143. [PMID: 28521222 DOI: 10.1016/j.biortech.2017.05.028] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/30/2017] [Revised: 05/03/2017] [Accepted: 05/04/2017] [Indexed: 06/07/2023]
Abstract
In this study, an actinomycete Streptomyces sp. hsn06 with the ability to harvest Chlorella vulgaris biomass was used to investigate the flocculation mechanism. Streptomyces sp. hsn06 exhibited flocculation activity on algal cells through mycelial pellets with adding calcium. Calcium was determined to promote flocculation activity of mycelial pellets as a bridge binding with mycelial pellets and algal cells, which implied that calcium bridging is the main flocculation mechanism for mycelial pellets. Characteristics of flocculation activity confirmed proteins in mycelial pellets involved in flocculation procedure. The morphology and structure of mycelial pellets also caused dramatic effects on flocculation activity of mycelial pellets. According to the results, Streptomyces sp. hsn06 can be used as a novel flocculating microbial resource for high-efficiency harvesting of microalgae biomass.
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Affiliation(s)
- Yi Li
- College of Life Sciences, Henan Normal University, Xinxiang 453007, China
| | - Yanting Xu
- College of Life Sciences, Henan Normal University, Xinxiang 453007, China
| | - Tianling Zheng
- State Key Laboratory of Marine Environmental Science, School of Life Sciences, Xiamen University, Xiamen 361005, China
| | - Hailei Wang
- College of Life Sciences, Henan Normal University, Xinxiang 453007, China.
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18
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Production, characterization and structural modification of exopolysaccharide-based bioflocculant by Rhizobium radiobacter SZ4S7S14 and media optimization. 3 Biotech 2017; 7:179. [PMID: 28664366 DOI: 10.1007/s13205-017-0811-9] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2016] [Accepted: 04/17/2017] [Indexed: 10/19/2022] Open
Abstract
Synthesis of the exopolysaccharide-based bioflocculant Rhizobium radiobacter SZ4S7S14 was researched and medium optimized for enhanced production of bioflocculant. D-Mannose and yeast extract were found to be best carbon and nitrogen sources for maximal yield of bioflocculant. The bioflocculant samples obtained in different media with different carbon and nitrogen sources were further analyzed by SEM-EDX and FT-IR. FT-IR spectroscopy of the bioflocculant samples, obtained in different carbon/nitrogen sources showed slight modification of the structures of biopolymers. SEM micrographs revealed that exopolysaccharide-based bioflocculant of R. radiobacter SZ4S7S14 looks like bricks, and chemical structure of it can be varied due to utilized carbon and nitrogen source.
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Ntsangani N, Okaiyeto K, Uchechukwu NU, Olaniran AO, Mabinya LV, Okoh AI. Bioflocculation potentials of a uronic acid-containing glycoprotein produced by Bacillus sp. AEMREG4 isolated from Tyhume River, South Africa. 3 Biotech 2017; 7:78. [PMID: 28500400 PMCID: PMC5429313 DOI: 10.1007/s13205-017-0695-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2017] [Accepted: 03/15/2017] [Indexed: 12/02/2022] Open
Abstract
Bioflocculants are secondary metabolites produced by microorganisms during their growth which have received attentions due to their biodegradability, innocuousness and lack of secondary pollution from degradation intermediates. This study reports on a bioflocculant produced by Bacillus specie isolated from Thyume River in South Africa. The bacterial isolate was identified through 16S rDNA sequencing and the BLAST analysis of the nucleotide sequences revealed 99% similarity to Bacillus sp. BCT-7112. The sequence was subsequently deposited in the GenBank as Bacillus sp. AEMREG4 with accession number KP406729. The optimum culture conditions for bioflocculant production were an inoculum size 4% (v/v) (80%) and starch (81%) as well as yeast extract (82%) as sole carbon and nitrogen sources, respectively. Addition of Ca2+ greatly enhanced the flocculating activity (76%) of crude bioflocculant over a wide range of pH 4–10 and retained high flocculating activity when heated at 100 °C for 1 h. Chemical analyses of the purified bioflocculant revealed carbohydrate (79% w/w) as a predominant component followed by uronic acid (15% w/w) and protein (5% w/w). Fourier transform infrared spectrum revealed the presence of carboxyl, hydroxyl and methoxyl groups as the functional groups responsible for flocculation and the high flocculation activity achieved portends its industrial applicability.
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Yin H, He Y, Deng Y, Dong J, Lu J, Chen L. Application of Plackett-Burman experimental design for investigating the effect of wort amino acids on flavour-active compounds production during lager yeast fermentation. JOURNAL OF THE INSTITUTE OF BREWING 2017. [DOI: 10.1002/jib.424] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Hua Yin
- The Key Laboratory of Industrial Biotechnology, Ministry of Education; Jiangnan University; Wuxi 214122 People's Republic of China
- National Engineering Laboratory for Cereal Fermentation Technology; Jiangnan University; Wuxi 214122 People's Republic of China
- School of Biotechnology; Jiangnan University; Wuxi 214122 People's Republic of China
- State Key Laboratory of Biological Fermentation Engineering of Beer; Tsingtao Brewery Co. Ltd Qingdao 266061 People's Republic of China
| | - Yang He
- State Key Laboratory of Biological Fermentation Engineering of Beer; Tsingtao Brewery Co. Ltd Qingdao 266061 People's Republic of China
| | - Yang Deng
- State Key Laboratory of Biological Fermentation Engineering of Beer; Tsingtao Brewery Co. Ltd Qingdao 266061 People's Republic of China
| | - Jianjun Dong
- School of Biotechnology; Jiangnan University; Wuxi 214122 People's Republic of China
- State Key Laboratory of Biological Fermentation Engineering of Beer; Tsingtao Brewery Co. Ltd Qingdao 266061 People's Republic of China
| | - Jian Lu
- The Key Laboratory of Industrial Biotechnology, Ministry of Education; Jiangnan University; Wuxi 214122 People's Republic of China
- National Engineering Laboratory for Cereal Fermentation Technology; Jiangnan University; Wuxi 214122 People's Republic of China
- School of Biotechnology; Jiangnan University; Wuxi 214122 People's Republic of China
| | - Lu Chen
- State Key Laboratory of Biological Fermentation Engineering of Beer; Tsingtao Brewery Co. Ltd Qingdao 266061 People's Republic of China
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Oyetibo GO, Miyauchi K, Suzuki H, Endo G. Mercury removal during growth of mercury tolerant and self-aggregating Yarrowia spp. AMB Express 2016; 6:99. [PMID: 27739052 PMCID: PMC5063827 DOI: 10.1186/s13568-016-0271-3] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2016] [Accepted: 10/04/2016] [Indexed: 11/10/2022] Open
Abstract
Ecotoxicological implications of mercury (Hg) pollution of hydrosphere require effective Hg-removal strategies as antidote to the environmental problems. Mercury-tolerant yeasts, Yarrowia spp. Idd1 and Idd2 strains, were studied for intracellular accumulation and extracellular micro-precipitation of Hg during growth stage of the yeast strains. In a liquid medium containing 870 (±23.6) µg of bioavailable Hg2+, 419.0 µg Hg2+ (approx.) was taken up by the wet biomasses of the yeast strains after 48 h post-inoculation. Large portion of the adsorbed Hg was found in cell wall (approx. 49-83 %) and spheroplast (approx. 62-89 %). Negligible quantities of Hg were present in the mitochondria (0.02-0.02 %), and appreciable amount of Hg was observed in nuclei and cell debris (15.2-65.3 %) as evidence of bioaccumulation. Extracellular polymeric substances (EPS) produced by the growing Yarrowia cells was a complex of protein, carbohydrates and other substances, immobilizing 43.8 (±0.7)-58.7 (±1.0) % of initial Hg in medium as micro-precipitates, while 10.13 ± 0.4-39.2 ± 4.3 % Hg content was volatilized. Transmission electron microscopy coupled with X-ray energy dispersive spectrophotometry confirmed the cellular removal of Hg and formation of EPS-Hg complex colloids in the surrounding bulk solution as micro-precipitates in form of extracellular Hg-nanoparticles. Hg mass balance in the bio-sequestration experiment revealed excellent Hg removal (>97 %) from the medium (containing ≤16 μg ml-1 Hg2+) by the yeast strains via bioaccumulation, volatilization and micro-precipitation. The yeast strains are also effectively applicable in biological purification technology for Hg contaminated water because of their high self-aggregation activity and separatability from the aquatic environments. Graphical abstract Yarrowia species are oligotrophic marine yeasts that exhibited great potentials for mercuric ion remediation technologies, which are classified into four categories based on the process acting on the metal. These include immobilization through biosorption, compartmentation via bioaccumulation, separation from bulk solution via micro-precipitation upon EPS-Hg complex formation, and destruction that is a process to reduce the mercuric ion to metallic mercury.
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Rasulov BA, Pattaeva MA, Yili A, Aisa HA. Polysaccharide-based bioflocculant template of a diazotrophic Bradyrhizobium japonicum 36 for controlled assembly of AgCl nanoparticles. Int J Biol Macromol 2016; 89:682-8. [DOI: 10.1016/j.ijbiomac.2016.03.067] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2016] [Revised: 03/22/2016] [Accepted: 03/29/2016] [Indexed: 11/29/2022]
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23
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Chen H, Zhong C, Berkhouse H, Zhang Y, Lv Y, Lu W, Yang Y, Zhou J. Removal of cadmium by bioflocculant produced by Stenotrophomonas maltophilia using phenol-containing wastewater. CHEMOSPHERE 2016; 155:163-169. [PMID: 27108374 DOI: 10.1016/j.chemosphere.2016.04.044] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/04/2016] [Revised: 04/08/2016] [Accepted: 04/12/2016] [Indexed: 05/22/2023]
Abstract
Bioflocculants have been applied in numerous applications including heavy metals removal. A major bottleneck for commercial application of bioflocculant is its high production cost. Phenol-containing wastewater are abundantly available. However, the toxic phenol inhibited the microbial activities in the subsequent fermentation processes. Consequently, strains that can secrete phenol-degrading enzymes and simultaneously produce bioflocculants through directly degrading the phenol are of academic and practical interests. A phenol-degrading strain, Stenotrophomonas maltophilia ZZC-06, which can produce the bioflocculant MBF-06 using phenol-containing wastewater, was isolated in this study. The effects of culture conditions including initial pH, dissolved oxygen, phenol concentration, inoculum size, and temperature on MBF-06 production were analyzed. The experimental results showed that over 90% flocculating activity was achieved when the phenol was used as a carbon source and 4.99 g/L of MBF-06 was achieved under the optimized condition: 2.0% dissolved oxygen, 800 mg/L phenol concentration, 10% inoculum size, an initial pH of 6.0, and a temperature of 30 °C. The bioflocculant MBF-06 contained 71.2% polysaccharides and 27.9% proteins. The feasibility of cadmium removal using MBF-06 was evaluated. The highest flocculating efficiency for cadmium was 81.43%. This study shows for the first time that Stenotrophomonas maltophilia ZZC-06 can directly convert phenol into a bioflocculant, which can be used to effectively remove cadmium.
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Affiliation(s)
- Honggao Chen
- School of Environmental Engineering, Wuhan Textile University, Wuhan 430073, China
| | - Chunying Zhong
- Hubei Key Laboratory of Purification and Application of Plant Anti-cancer Active Ingredients, Chemistry and Biology Science College, Hubei University of Education, Wuhan 430205, China
| | - Hudson Berkhouse
- College of Agriculture and Life Sciences, Texas A&M University, College Station, TX 77843, USA
| | - Youlang Zhang
- Department of Political Science, Texas A&M University, College Station 77843, USA
| | - Yao Lv
- School of Environmental Engineering, Wuhan Textile University, Wuhan 430073, China
| | - Wanyu Lu
- School of Environmental Engineering, Wuhan Textile University, Wuhan 430073, China
| | - Yongbing Yang
- College of Economics and Management, Nanjing Agricultural University, Nanjing 210095, China
| | - Jiangang Zhou
- School of Environmental Engineering, Wuhan Textile University, Wuhan 430073, China.
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Rasulov BA, Rozi P, Pattaeva MA, Yili A, Aisa HA. Exopolysaccharide-Based Bioflocculant Matrix of Azotobacter chroococcum XU1 for Synthesis of AgCl Nanoparticles and Its Application as a Novel Biocidal Nanobiomaterial. MATERIALS 2016; 9:ma9070528. [PMID: 28773650 PMCID: PMC5456945 DOI: 10.3390/ma9070528] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/24/2016] [Revised: 06/22/2016] [Accepted: 06/25/2016] [Indexed: 11/16/2022]
Abstract
A simple and green method was developed for the biosynthesis of AgCl nanoparticles, free from Ag nanoparticles, using the exopolysaccharide-based bioflocculant of nitrogen fixing Azotobacter chroococcum XU1 strain. AgCl nanoparticles were characterized by UV-Vis, X-ray diffraction (XRD), Fourier Transform-Infra Red (FT-IR) and Scanning electron microscopy-energy dispersive X-ray (SEM-EDX). The concentration-dependent and controllable method for the synthesis of AgCl nanoparticles of a certain size and morphology was developed. As-synthesized AgCl nanoparticles were characterized bya high content of AgCl and exhibited strong antimicrobial activity towards pathogenic microorganisms such as E. coli, S. aureus and C. albicans. The biofabricated AgCl nanoparticles can be exploited as a promising new biocidalbionanocomposite against pathogenic microorganisms.
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Affiliation(s)
- Bakhtiyor A Rasulov
- Institute of Genetics and Plant Experimental Biology, Uzbekistan Academy of Sciences, Yukori Yuz, Kybray District 111226, Uzbekistan.
| | - Parhat Rozi
- Key Laboratory of Plant Resources and Chemistry in Arid Region, Xinjiang Technical Institute of Chemistry and Physics, Chinese Academy of Sciences, Urumqi 830011, China.
- University of Chinese Academy of Sciences, Beijing 100039, China.
| | - Mohichehra A Pattaeva
- Institute of Microbiology, Uzbekistan Academy of Sciences, Tashkent 100128, Uzbekistan.
| | - Abulimiti Yili
- Key Laboratory of Plant Resources and Chemistry in Arid Region, Xinjiang Technical Institute of Chemistry and Physics, Chinese Academy of Sciences, Urumqi 830011, China.
| | - Haji Akber Aisa
- Key Laboratory of Plant Resources and Chemistry in Arid Region, Xinjiang Technical Institute of Chemistry and Physics, Chinese Academy of Sciences, Urumqi 830011, China.
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Okaiyeto K, Nwodo UU, Okoli SA, Mabinya LV, Okoh AI. Implications for public health demands alternatives to inorganic and synthetic flocculants: bioflocculants as important candidates. Microbiologyopen 2016; 5:177-211. [PMID: 26914994 PMCID: PMC4831466 DOI: 10.1002/mbo3.334] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2015] [Revised: 11/05/2015] [Accepted: 11/24/2015] [Indexed: 12/11/2022] Open
Abstract
Chemical flocculants are generally used in drinking water and wastewater treatment due to their efficacy and cost effectiveness. However, the question of their toxicity to human health and environmental pollution has been a major concern. In this article, we review the application of some chemical flocculants utilized in water treatment, and bioflocculants as a potential alternative to these chemical flocculants. To the best of our knowledge, there is no report in the literature that provides an up‐to‐date review of the relevant literature on both chemical flocculants and bioflocculants in one paper. As a result, this review paper comprehensively discussed the various chemical flocculants used in water treatment, including their advantages and disadvantages. It also gave insights into bioflocculants production, challenges, various factors influencing their flocculating efficiency and their industrial applications, as well as future research directions including improvement of bioflocculants yields and flocculating activity, and production of cation‐independent bioflocculants. The molecular biology and synthesis of bioflocculants are also discussed.
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Affiliation(s)
- Kunle Okaiyeto
- SAMRC Microbial Water Quality Monitoring Centre, University of Fort Hare, Alice, 5700, South Africa.,Applied and Environmental Microbiology Research Group (AEMREG), Department of Biochemistry and Microbiology, University of Fort Hare, Alice, 5700, South Africa
| | - Uchechukwu U Nwodo
- SAMRC Microbial Water Quality Monitoring Centre, University of Fort Hare, Alice, 5700, South Africa.,Applied and Environmental Microbiology Research Group (AEMREG), Department of Biochemistry and Microbiology, University of Fort Hare, Alice, 5700, South Africa
| | - Stanley A Okoli
- GenØK - Centre for Biosafety, Science Park, University of Tromsø, Tromsø, 9291, Norway
| | - Leonard V Mabinya
- SAMRC Microbial Water Quality Monitoring Centre, University of Fort Hare, Alice, 5700, South Africa.,Applied and Environmental Microbiology Research Group (AEMREG), Department of Biochemistry and Microbiology, University of Fort Hare, Alice, 5700, South Africa
| | - Anthony I Okoh
- SAMRC Microbial Water Quality Monitoring Centre, University of Fort Hare, Alice, 5700, South Africa.,Applied and Environmental Microbiology Research Group (AEMREG), Department of Biochemistry and Microbiology, University of Fort Hare, Alice, 5700, South Africa
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Purification and characterization of exopolysaccharide bioflocculant produced by heavy metal resistant Achromobacter xylosoxidans. Carbohydr Polym 2016; 137:441-451. [DOI: 10.1016/j.carbpol.2015.10.066] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2015] [Revised: 09/21/2015] [Accepted: 10/17/2015] [Indexed: 11/19/2022]
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Okaiyeto K, Nwodo UU, Mabinya LV, Okoli AS, Okoh AI. Evaluation of flocculating performance of a thermostable bioflocculant produced by marine Bacillus sp. ENVIRONMENTAL TECHNOLOGY 2016; 37:1829-1842. [PMID: 26797258 DOI: 10.1080/09593330.2015.1133717] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
This study assessed the bioflocculant (named MBF-W7) production potential of a bacterial isolate obtained from Algoa Bay, Eastern Cape Province of South Africa. The 16S ribosomal deoxyribonucleic acids gene sequence analysis showed 98% sequence similarity to Bacillus licheniformis strain W7. Optimum culture conditions for MBF-W7 production include 5% (v/v) inoculum size, maltose and NH4NO3 as carbon and nitrogen sources of choice, medium pH of 6 as the initial pH of the growth medium. Under these optimal conditions, maximum flocculating activity of 94.9% was attained after 72 h of cultivation. Chemical composition analyses showed that the purified MBF-W7 was a glycoprotein which was predominantly composed of polysaccharides 73.7% (w/w) and protein 6.2% (w/w). Fourier transform infrared spectroscopy revealed the presence of hydroxyl, carboxyl and amino groups as the main functional groups identified in the bioflocculant molecules. Thermogravimetric analyses showed the thermal decomposition profile of MBF-W7. Scanning electron microscopy imaging revealed that bridging played an important role in flocculation. MBF-W7 exhibited excellent flocculating activity for kaolin clay suspension at 0.2 mg/ml over a wide pH range of 3-11; with the maximal flocculation rate of 85.8% observed at pH 3 in the presence of Mn(2+). It maintained and retained high flocculating activity of over 70% after heating at 100°C for 60 min. MBF-W7 showed good turbidity removal potential (86.9%) and chemical oxygen demand reduction efficiency (75.3%) in Tyume River. The high flocculating rate of MBF-W7 makes it an attractive candidate to replace chemical flocculants utilized in water treatment.
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Affiliation(s)
- Kunle Okaiyeto
- a South Africa Medical Research Council (SAMRC), Microbial Water Quality Monitoring Centre , University of Fort Hare , Alice , South Africa
- b Applied and Environmental Microbiology Research Group, Department of Biochemistry and Microbiology , University of Fort Hare , Alice , South Africa
| | - Uchechukwu U Nwodo
- a South Africa Medical Research Council (SAMRC), Microbial Water Quality Monitoring Centre , University of Fort Hare , Alice , South Africa
- b Applied and Environmental Microbiology Research Group, Department of Biochemistry and Microbiology , University of Fort Hare , Alice , South Africa
| | - Leonard V Mabinya
- a South Africa Medical Research Council (SAMRC), Microbial Water Quality Monitoring Centre , University of Fort Hare , Alice , South Africa
- b Applied and Environmental Microbiology Research Group, Department of Biochemistry and Microbiology , University of Fort Hare , Alice , South Africa
| | - Arinze S Okoli
- c GenØK Centre for Biosafety , Forskningsparken i Breivika , Tromsø , Norway
| | - Anthony I Okoh
- a South Africa Medical Research Council (SAMRC), Microbial Water Quality Monitoring Centre , University of Fort Hare , Alice , South Africa
- b Applied and Environmental Microbiology Research Group, Department of Biochemistry and Microbiology , University of Fort Hare , Alice , South Africa
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28
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Zhong CY, Chen HG, Cao G, Wang J, Zhou JG. Bioflocculant production by Haloplanus vescus and its application in acid brilliant scarlet yellow/red removal. WATER SCIENCE AND TECHNOLOGY : A JOURNAL OF THE INTERNATIONAL ASSOCIATION ON WATER POLLUTION RESEARCH 2016; 73:707-715. [PMID: 26901711 DOI: 10.2166/wst.2015.549] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
A novel bioflocculant MBF057 produced by a salt-tolerant Haloplanus vescus HW0579 was investigated in this study. The effects of culture conditions such as initial pH, inoculum size, and chemical oxygen demand (COD) of K-acid wastewater on MBF0579 production were studied. The result showed that 8.09 g/L purified MBF0579 was extracted with the following optimized conditions: 780 mg/L COD of K-acid wastewater as carbon source, inoculum size 12.5%, and initial pH 7.0. The biopolymer contained 78.6% polysaccharides and 21.1% proteins. The highest flocculating rate of 81.86 and 95.07% for the COD and chroma of acid brilliant scarlet gelb rot (yellow/red, GR) dye wastewater were achieved at a dosage of 150 mg/L, pH 2.0 and contact time 100 min. Overall, these findings indicate bioflocculation offers an effective alternative method of decreasing acid brilliant scarlet GR during dye wastewater treatment.
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Affiliation(s)
- Chun-Ying Zhong
- School of Environmental Engineering, Wuhan Textile University, Wuhan 430073, China E-mail: ; Hubei Key Laboratory of Purification and Application of Plant Anticancer Active Ingredients, Chemistry and Biology Science College, Hubei University of Education, Wuhan 430205, China; These two authors contributed equally to this work
| | - Hong-Gao Chen
- School of Environmental Engineering, Wuhan Textile University, Wuhan 430073, China E-mail: ; These two authors contributed equally to this work
| | - Gang Cao
- School of Environmental Engineering, Wuhan Textile University, Wuhan 430073, China E-mail:
| | - Jun Wang
- School of Environmental Engineering, Wuhan Textile University, Wuhan 430073, China E-mail:
| | - Jian-Gang Zhou
- School of Environmental Engineering, Wuhan Textile University, Wuhan 430073, China E-mail:
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29
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Okaiyeto K, Nwodo UU, Mabinya LV, Okoli AS, Okoh AI. Characterization of a Bioflocculant (MBF-UFH) Produced by Bacillus sp. AEMREG7. Int J Mol Sci 2015; 16:12986-3003. [PMID: 26062133 PMCID: PMC4490482 DOI: 10.3390/ijms160612986] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2015] [Revised: 05/10/2015] [Accepted: 05/11/2015] [Indexed: 01/28/2023] Open
Abstract
A bioflocculant named MBF-UFH produced by a Bacillus species isolated from sediment samples of Algoa Bay of the Eastern Cape Province of South Africa was characterized. The bacterial identification was through 16S rDNA sequencing; nucleotide sequences were deposited in GenBank as Bacillus sp. AEMREG7 with Accession Number KP659187. The production of the bioflocculant was observed to be closely associated with cell growth. The bioflocculant had the highest flocculating activity of 83.2% after 72 h of cultivation, and approximately 1.6 g of purified MBF-UFH was recovered from 1 L of fermentation broth. Its chemical analyses indicated that it is a glycoprotein composed of polysaccharide (76%) and protein (14%). Fourier transform infrared spectroscopy (FTIR) revealed that it consisted of hydroxyl, amide, carboxyl and methoxyl as the functional moieties. Scanning electron microscopy (SEM) revealed the amorphous structure of MBF-UFH and flocculated kaolin clay particles. The maximum flocculating activity of 92.6% against kaolin clay suspension was achieved at 0.3 mg/mL over pH ranges of 3-11 with the peak flocculating rate at pH 8 in the presence of MgCl2. The bioflocculant retained high flocculating activity of 90% after heating at 100 °C for 1 h. MBF-UFH appears to have immense potential as an alternative to conventional chemical flocculants.
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Affiliation(s)
- Kunle Okaiyeto
- South Africa-Medical Research Council (SA-MRC), Microbial Water Quality Monitoring Centre, University of Fort Hare, 5700 Alice, South Africa.
- Applied and Environmental Microbiology Research Group, Department of Biochemistry and Microbiology, University of Fort Hare, 5700 Alice, South Africa.
| | - Uchechukwu U Nwodo
- South Africa-Medical Research Council (SA-MRC), Microbial Water Quality Monitoring Centre, University of Fort Hare, 5700 Alice, South Africa.
- Applied and Environmental Microbiology Research Group, Department of Biochemistry and Microbiology, University of Fort Hare, 5700 Alice, South Africa.
| | - Leonard V Mabinya
- South Africa-Medical Research Council (SA-MRC), Microbial Water Quality Monitoring Centre, University of Fort Hare, 5700 Alice, South Africa.
- Applied and Environmental Microbiology Research Group, Department of Biochemistry and Microbiology, University of Fort Hare, 5700 Alice, South Africa.
| | - Arinze S Okoli
- GenØK-Centre for Biosafety, Forskningsparken i Breivika, Postboks 6418, 9294 Tromsø, Norway.
| | - Anthony I Okoh
- South Africa-Medical Research Council (SA-MRC), Microbial Water Quality Monitoring Centre, University of Fort Hare, 5700 Alice, South Africa.
- Applied and Environmental Microbiology Research Group, Department of Biochemistry and Microbiology, University of Fort Hare, 5700 Alice, South Africa.
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Production of polysaccharide-based bioflocculant for the synthesis of silver nanoparticles by Streptomyces sp. Int J Biol Macromol 2015; 77:159-67. [PMID: 25799882 DOI: 10.1016/j.ijbiomac.2015.03.022] [Citation(s) in RCA: 48] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2015] [Revised: 03/04/2015] [Accepted: 03/15/2015] [Indexed: 11/20/2022]
Abstract
Polysaccharide-based bioflocculants have attracted considerable attention in recent years due to their biodegradable, harmless and negligible secondary pollution. Bioflocculants are organic macromolecular substances secreted by microorganisms. A simple, cost-effective and green method was developed for the biosynthesis of silver nanoparticles using polysaccharides as reducing and stabilizing agents. In this paper, we report on the production and optimization of polysaccharide-based bioflocculant for the green synthesis of silver nanoparticles by Streptomyces sp. MBRC-91. Medium composition and culture conditions for polysaccharide-based bioflocculants were statistically optimized by response surface methodology (RSM). The bioflocculant production was statistically optimized with most significant factors, namely palm jaggery (18.73g/L), yeast extract (2.07g/L), K2HPO4 (3.74g/L) and NaCl (0.38g/L), respectively. The biosynthesized silver nanoparticles were characterized by UV-vis spectroscopy, XRD, FTIR, FESEM, EDXA and HRTEM. The biosynthesized silver nanoparticles revealed strong antibacterial activity in sewage water and this result could make a new avenue in the wastewater treatment. Therefore, the biosynthesized silver nanoparticles can be extended as an alternative for the development of new bactericidal bionanomaterials for wastewater treatment and biotechnological applications.
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Salehizadeh H, Yan N. Recent advances in extracellular biopolymer flocculants. Biotechnol Adv 2014; 32:1506-22. [DOI: 10.1016/j.biotechadv.2014.10.004] [Citation(s) in RCA: 87] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2014] [Revised: 10/02/2014] [Accepted: 10/07/2014] [Indexed: 10/24/2022]
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Zhou W, Liu X, Zhang P, Zhou P, Shi X. Effect analysis of mineral salt concentrations on nosiheptide production by Streptomyces actuosus Z-10 using response surface methodology. Molecules 2014; 19:15507-20. [PMID: 25264834 PMCID: PMC6270855 DOI: 10.3390/molecules191015507] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2014] [Revised: 09/02/2014] [Accepted: 09/12/2014] [Indexed: 11/26/2022] Open
Abstract
The objective of this study was to develop an optimal combination of mineral salts in the fermentation medium for nosiheptide (Nsh) production using statistical methodologies. A Plackett-Burman design (PBD) was used to evaluate the impacts of eight mineral salts on Nsh production. The results showed that among the no-significant factors, CaCO3, and K2HPO4·3H2O had positive effects, whereas FeSO4·7H2O, CuSO4·5H2O, and ZnSO4·7H2O had negative effects on Nsh production. The other three significant factors (Na2SO4, MnSO4·H2O, and MgSO4·7H2O) were further optimized by using a five-level three-factor central composite design (CCD). Experimental data were fitted to a quadratic polynomial model, which provided an effective way to determine the interactive effect of metal salts on Nsh production. The optimal values were determined to be 2.63, 0.21, and 3.37 g/L, respectively. The model also ensured a good fitting of scale-up Nsh batch fermentation with a maximum production of 1501 mg/L, representing a 1.56-fold increase compared to the original standard condition. All these results revealed that statistical optimization methodology had the potential to achieve comprehensive optimization in Nsh fermentation behaviors, which indicates a possibility to establish economical large-scale production of Nsh.
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Affiliation(s)
- Wei Zhou
- Department of Chemistry, Fudan University, 220 Handan Road, Shanghai 200433, China
| | - Xiaohui Liu
- College of Chemistry and Chemical Engineering, Shanghai University of Engineering Science, 333 Longteng Road, Shanghai 201620, China
| | - Pei Zhang
- CAS Key Laboratory of Synthetic Chemistry of Natural Substances, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, China
| | - Pei Zhou
- School of Pharmacy, Fudan University, 826 Zhangheng Road, Shanghai 201203, China
| | - Xunlong Shi
- School of Pharmacy, Fudan University, 826 Zhangheng Road, Shanghai 201203, China.
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Zhong C, Xu A, Wang B, Yang X, Hong W, Yang B, Chen C, Liu H, Zhou J. Production of a value added compound from the H-acid waste water-Bioflocculants by Klebsiella pneumoniae. Colloids Surf B Biointerfaces 2014; 122:583-590. [PMID: 25127749 DOI: 10.1016/j.colsurfb.2014.07.036] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2014] [Revised: 07/20/2014] [Accepted: 07/22/2014] [Indexed: 11/25/2022]
Abstract
A novel strain (designated as ZCY-7) which could convert H-acid into bioflocculants was isolated from H-acid wastewater sludge. Conditions for bioflocculants production were optimized by response surface methodology (RSM) and determined to be inoculum size 9.65%, initial pH 7.0, and CODCr of the H-acid wastewater 520mg/L. The highest flocculating efficiency achieved for kaolin suspension was 95.1%, after 60h cultivation. The yielded bioflocculant was mainly composed of polysaccharide (82.4%) and protein (14.2%), and maintained its flocculating activity in 0.4% (w/w) kaolin suspensions over pH 2-8 and 20-80°C. Fourier transform infrared (FTIR) spectra showed that amino, amide and hydroxyl groups were present in the bioflocculant molecules. A viable alternative treatment technology of H-acid wastewater using this novel strain is suggested, which could largely reduce bioflocculants costs. In addition, flocculating mechanism investigation reveals that the bioflocculant could cause kaolin suspension instability by means of charge neutralization firstly and then promoted the aggregation of suspension particles by adsorption and bridge. It is evident from the results that H-acid wastewater could be used as a source to manufacture bioflocculants.
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Affiliation(s)
- Chunying Zhong
- School of Environmental Engineering, Wuhan Textile University, Wuhan 430073, China; School of Chemistry and Life Science, Hubei University of Education, Wuhan 430205, China
| | - Aihua Xu
- School of Environmental Engineering, Wuhan Textile University, Wuhan 430073, China
| | - Buyun Wang
- School of Environmental Engineering, Wuhan Textile University, Wuhan 430073, China
| | - Xianghui Yang
- School of Environmental Engineering, Wuhan Textile University, Wuhan 430073, China
| | - Wentao Hong
- School of Environmental Engineering, Wuhan Textile University, Wuhan 430073, China
| | - Baokun Yang
- School of Environmental Engineering, Wuhan Textile University, Wuhan 430073, China
| | - Changhong Chen
- School of Environmental Engineering, Wuhan Textile University, Wuhan 430073, China
| | - Hongtao Liu
- School of Materials Science and Engineering, Wuhan Textile University, Wuhan 430073, China
| | - Jiangang Zhou
- School of Environmental Engineering, Wuhan Textile University, Wuhan 430073, China.
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Nwodo UU, Okoh AI. Mixed culture fermentation and media optimization by response surface model: Streptomyces and Brachybacterium species in bioflocculant production. Molecules 2014; 19:11131-44. [PMID: 25076145 PMCID: PMC6271801 DOI: 10.3390/molecules190811131] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2014] [Revised: 07/14/2014] [Accepted: 07/21/2014] [Indexed: 12/02/2022] Open
Abstract
The biofloculant production potential of a consortium of Streptomyces and Brachybacterium species were evaluated. Optimum bioflocculant yields (g/L) and flocculation activities (%) were observed for the following preferred nutritional sources: glucose (56%; 2.78 ± 0.15 g/L), (NH4)2NO3 (53%; 2.81 ± 0.37 g/L) and CaSO4·H2O (47%; 2.19 ± 0.13 g/L). A Plackett-Burman design revealed the critical fermentation media components. The concentrations of these components were optimized [glucose; 16.0, (NH4)2NO3; 0.5 and CaSO4·H2O; 1.2 (g/L)] through a central composite design with optimum bioflocculant yield of 3.02 g/L and flocculation activity of 63.7%. The regression coefficient (R2 = 0.6569) indicates a weak estimation of the model’s adequacy and a high lack-of-fit value (34.1%). Lack of synergy in the consortium may have been responsible for the model inadequacy observed. FTIR spectrometry showed the bioflocculant to be a heteropolysaccharide, while SEM imaging revealed an amorphous loosely arranged fluffy structure with interstial spacing of less than 1 µm.
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Affiliation(s)
- Uchechukwu U Nwodo
- Applied and Environmental Microbiology Research Group (AEMREG), Department of Biochemistry and Microbiology, University of Fort Hare, Private Bag X1314, Alice 5700, South Africa.
| | - Anthony I Okoh
- Applied and Environmental Microbiology Research Group (AEMREG), Department of Biochemistry and Microbiology, University of Fort Hare, Private Bag X1314, Alice 5700, South Africa.
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