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Zhang J, Lu Z, Feng L, Qu D, Zhu J. Identification of microbial communities and multi-species biofilms contamination in seafood processing environments with different hygiene conditions. Food Microbiol 2024; 122:104553. [PMID: 38839233 DOI: 10.1016/j.fm.2024.104553] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2024] [Revised: 04/15/2024] [Accepted: 04/19/2024] [Indexed: 06/07/2024]
Abstract
Biofilms formed by spoilage and pathogenic bacteria increase microbial persistence, causing an adverse influence on the quality of seafood. The mono-species biofilms are widely reported, however, the contamination of multi-species biofilms and their matrix in food environments are still not fully understood. Here, we assessed the contamination of multi-species biofilms in three seafood processing environments with different hygiene levels by detecting bacterial number and three biofilm matrix components (carbohydrates, extracellular DNA (eDNA), and proteins). Samples comprising seven food matrix surfaces and eight food processing equipment surfaces were collected from two seafood processing plants (XY and XC) and one seafood market (CC). The results showed that the bacterial counts ranged from 1.89 to 4.91 CFU/cm2 and 5.68 to 9.15 BCE/cm2 in these surfaces by cultivation and real-time PCR, respectively. Six biofilm hotspots were identified, including four in CC and two in XY. Among the three processing environments, the amplicon sequence variants (ASVs) of Proteobacteria, Bacteroidetes, and Actinobacteria decreased with improved processing hygiene, while Firmicutes showed a decrease in the four most abundant phyla. The most prevalent bacteria belonged to genera Psychrobacter, Acinetobacter, and Pseudomonas, demonstrating the significant differences and alteration in bacterial community composition during different environments. From the biofilm hotspots, 15 isolates with strong biofilm forming ability were identified, including 7 Pseudomonas, 7 Acinetobacter, and 1 Psychrobacter. The Pseudomonas isolates exhibited the highest production of EPS components and three strong motilities, whose characteristics were positively correlated. Thus, this study verified the presence of multi-species biofilms in seafood processing environments, offering preliminary insights into the diversity of microbial communities during processing. It highlights potential contamination sources and emphasizes the importance of understanding biofilms composition to control biofilms formation in seafood processing environments.
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Affiliation(s)
- Jun Zhang
- College of Food Science and Biotechnology, Food Safety Key Laboratory of Zhejiang Province, Zhejiang Gongshang University, Hangzhou, Zhejiang, 310018, China
| | - Zhong Lu
- College of Food Science and Biotechnology, Food Safety Key Laboratory of Zhejiang Province, Zhejiang Gongshang University, Hangzhou, Zhejiang, 310018, China
| | - Lifang Feng
- College of Food Science and Biotechnology, Food Safety Key Laboratory of Zhejiang Province, Zhejiang Gongshang University, Hangzhou, Zhejiang, 310018, China
| | - Daofeng Qu
- College of Food Science and Biotechnology, Food Safety Key Laboratory of Zhejiang Province, Zhejiang Gongshang University, Hangzhou, Zhejiang, 310018, China
| | - Junli Zhu
- College of Food Science and Biotechnology, Food Safety Key Laboratory of Zhejiang Province, Zhejiang Gongshang University, Hangzhou, Zhejiang, 310018, China.
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2
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Saubade F, Cossec N, Giguelay Gesret L, Kouamé C, Ellouze M, Gérard C, Couvert O, Desriac N. Heat resistance of five spoilage microorganisms in a carbonated broth. Food Microbiol 2024; 122:104545. [PMID: 38839231 DOI: 10.1016/j.fm.2024.104545] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2024] [Revised: 04/09/2024] [Accepted: 04/13/2024] [Indexed: 06/07/2024]
Abstract
Despite their acidic pH, carbonated beverages can be contaminated by spoilage microorganisms. Thermal treatments, before and/or after carbonation, are usually applied to prevent the growth of these microorganisms. However, the impact of CO2 on the heat resistance of spoilage microorganisms has never been studied. A better understanding of the combined impact of CO2 and pH on the heat resistance of spoilage microorganisms commonly found in carbonated beverages might allow to optimize thermal treatment. Five microorganisms were selected for this study: Alicyclobacillus acidoterrestris (spores), Aspergillus niger (spores), Byssochlamys fulva (spores), Saccharomyces cerevisiae (vegetative cells), and Zygosaccharomyces parabailii (vegetative cells). A method was developed to assess the impact of heat treatments in carbonated media on microbial resistance. The heat resistances of the five studied species are coherent with the literature, when data were available. However, neither the dissolved CO2 concentration (from 0 to 7 g/L), nor the pH (from 2.8 to 4.1) have an impact on the heat resistance of the selected microorganisms, except for As. niger, for which the presence of dissolved CO2 reduced the heat resistance. This study improved our knowledge about the heat resistance of some spoilage microorganisms in presence of CO2.
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Affiliation(s)
- Fabien Saubade
- Univ Brest, INRAE, Laboratoire Universitaire de Biodiversité et Écologie Microbienne, F-29000, Quimper, France.
| | - Noëmie Cossec
- Univ Brest, INRAE, Laboratoire Universitaire de Biodiversité et Écologie Microbienne, F-29000, Quimper, France.
| | - Luc Giguelay Gesret
- Univ Brest, INRAE, Laboratoire Universitaire de Biodiversité et Écologie Microbienne, F-29000, Quimper, France.
| | - Christelle Kouamé
- NPTC Nestlé Waters, 1020 avenue Georges Clémenceau, F-88800, Vittel, France.
| | | | | | - Olivier Couvert
- Univ Brest, INRAE, Laboratoire Universitaire de Biodiversité et Écologie Microbienne, F-29000, Quimper, France.
| | - Noémie Desriac
- Univ Brest, INRAE, Laboratoire Universitaire de Biodiversité et Écologie Microbienne, F-29000, Quimper, France.
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3
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Ramesh R, Sathiyamurthy K, Meganathan V, Athmanathan B. Induction and comparative resuscitation of viable but nonculturable state on Vibrio parahaemolyticus serotypes O3:K6 and O1:K25. Arch Microbiol 2024; 206:376. [PMID: 39141167 DOI: 10.1007/s00203-024-04102-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2024] [Revised: 07/11/2024] [Accepted: 08/03/2024] [Indexed: 08/15/2024]
Abstract
Vibrio parahaemolyticus, an important food-borne pathogens found to be associated with seafoods and marine environs. It has been a topic of debate for many decades that most pathogens are known to enter a viable but nonculturable (VBNC) state under cold temperature and nutrient limited conditions. The present study examined the time required for the induction of VBNC state and the revival strategies of both the endemic O3:K6 and O1:K25 sporadic strains of V. parahaemolyticus. The results revealed that V. parahaemolyticus survived even after 55 days of incubation in nutrient starved media such as phosphate buffered saline (PBS) and Coastal Water (CW) and could be recovered by temperature upshift method, and compared the resuscitation using Dulbecco's Modified Eagle Medium (DMEM), sheep blood serum, chitin flakes with live Artemia salina, and the results suggests that chitin plays a significant role in regulating the VBNC state. It was also confirmed by Confocal Laser Scanning Microscopy (CLSM) and Scanning Electron Microscope (SEM) analysis that VBNC cells can alter their morphology to coccoid forms in order to survive in most extreme nutrient limited environment. Further data on the promoting factors and the exact mechanism that resuscitate VBNC V. parahaemolyticus in cold natural environments and frozen foods are needed to perform a robust risk assessment.
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Affiliation(s)
- Rohini Ramesh
- School of Life Sciences, B.S.Abdur Rahman Crescent Institute of Science and Technology, GST Road, Vandalur, Chennai, Tamil Nadu, 600048, India
| | - Karuppanan Sathiyamurthy
- Department of Bio Medical Science, School of Biotechnology and Genetic Engineering, Bharathidasan University, Tiruchirappalli, Tamil Nadu, 620 024, India
| | - Velmurugan Meganathan
- Department of Cellular and Molecular Biology Lab, University of Texas Health Science Center at Tyler, Tyler, USA
| | - Baskaran Athmanathan
- School of Life Sciences, B.S.Abdur Rahman Crescent Institute of Science and Technology, GST Road, Vandalur, Chennai, Tamil Nadu, 600048, India.
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4
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Li L, Bae S. Quantitative detection and survival analysis of VBNC Salmonella Typhimurium in flour using droplet digital PCR and DNA-intercalating dyes. Microbiol Spectr 2024; 12:e0024924. [PMID: 38975767 PMCID: PMC11302299 DOI: 10.1128/spectrum.00249-24] [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: 01/25/2024] [Accepted: 05/13/2024] [Indexed: 07/09/2024] Open
Abstract
The difficulty in detecting viable but non-culturable (VBNC) Salmonella by culture-dependent methods poses a risk to food safety. In our study, we applied a viability test to Salmonella following a lethal treatment and to flour samples inoculated with Salmonella to evaluate the effectiveness of viability polymerase chain reaction (PCR). Our findings revealed that the combination of both ddPCR and qPCR with those DNA-intercalating dyes could quantify viable cells at low concentrations when the plate counting method failed to detect them post-inactivation. Prolonged UV exposure did not induce cell membrane disruption, as confirmed with PMA-ddPCR, with insignificant differences in gene copies. However, samples exposed to DyeTox13 and DyeTox13 + EMA showed lower gene copy numbers, implying that enzymatic activity was decreased by UV exposure duration. In addition, temperature-dependent survival in flour revealed uniform decay rates and D values (time required for a 1 log reduction) of DNA in untreated samples across various temperatures. By contrast, different decay rates were observed with DNA-intercalating dyes (DyeTox13 and DyeTox13 + EMA), showing faster metabolic activity loss at higher temperatures in flour. The decay rates and D values, determined through plate counting and those DNA-intercalating dyes, indicated the potential presence of VBNC Salmonella. A strong correlation between DyeTox13 dyes and the plate counting method suggested DyeTox13 as a rapid alternative for detecting Salmonella in flour. The ddPCR with DNA-intercalating dyes could effectively evaluate Salmonella viability, facilitating more precise monitoring of VBNC in food. IMPORTANCE Salmonella, a major foodborne pathogen, poses significant risks, particularly to vulnerable groups like infants, older people, and the immunocompromised. Accurate detection is vital for public health and food safety, given its potential to cause severe and life-threatening symptoms. Our study demonstrated digital polymerase chain reaction (ddPCR) with DNA-intercalating dyes for identifying the different physiological statuses of Salmonella. Also, the application of ddPCR with DNA-intercalating dyes offers quantification of viable cells post-disinfection as an alternative method in food. Utilizing ddPCR and DNA-intercalating dyes, we enhanced the detection of VBNC Salmonella, a form often undetectable by conventional methods. This innovative approach could significantly improve the precision and efficiency of detection for viable Salmonella. By providing deeper insights into its transmission potential, our method is a critical tool in preventing outbreaks and ensuring the safety of food products. This research contributes substantially to global efforts in controlling foodborne illnesses and safeguarding public health.
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Affiliation(s)
- Liyan Li
- Department of Civil and Environmental Engineering, College of Design and Engineering, National University of Singapore, Singapore, Singapore
| | - Sungwoo Bae
- Department of Civil and Environmental Engineering, College of Design and Engineering, National University of Singapore, Singapore, Singapore
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5
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Somerton BT, Morgan BL. Comparison of plate counting with flow cytometry, using four different fluorescent dye techniques, for the enumeration of Bacillus cereus in milk. J Microbiol Methods 2024; 223:106978. [PMID: 38936432 DOI: 10.1016/j.mimet.2024.106978] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2024] [Revised: 06/23/2024] [Accepted: 06/24/2024] [Indexed: 06/29/2024]
Abstract
This study aimed to compare the performance of flow cytometry methods with plate counting for the enumeration of bacteria, using Bacillus cereus as a model organism. It was found that the cFDA-propidium iodide, CellROX™ Green-propidium iodide, and DiOC2 dye techniques had similar accuracy to plate counting, while the SYTO 24-propidium iodide dye technique was not as accurate. The four dye techniques had comparable precision to plate counting, with the CellROX™ Green-propidium iodide dye having the greatest precision. The consistency of the position and shape of the cell clusters on the flow cytometry plots, and the extent of separation of the cell from background clusters, was greatest with the DiOC2 and CellROX™ Green-propidium iodide dyes. Furthermore, the DiOC2 and CellROX™ Green-propidium iodide dyes performed well, even when a sample was measured containing reconstituted whole milk powder at a 10-1 dilution, without the use of sample preparation to specifically remove the milk constituents prior to measurement. Given gating of only one cell cluster was required to be managed with the DiOC2 dye, to determine the viable number of cells, it was found that the DiOC2 dye had the greatest ease-of-use. Overall, results indicated that the DiOC2 dye is an ideal candidate for the enumeration of viable bacteria in dairy samples on a high-throughput, routine basis.
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Affiliation(s)
- Ben T Somerton
- Fonterra Research & Development Centre, Fonterra, Palmerston North, New Zealand.
| | - Brooke L Morgan
- Fonterra Research & Development Centre, Fonterra, Palmerston North, New Zealand
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6
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Jiang Z, Wang Y, Bai S, Bai C, Tu Z, Li H, Guo P, Liao T, Qiu L. The viable but non-culturable (VBNC) status of Shewanella putrefaciens (S. putrefaciens) with thermosonication (TS) treatment. ULTRASONICS SONOCHEMISTRY 2024; 109:107008. [PMID: 39096846 DOI: 10.1016/j.ultsonch.2024.107008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/22/2024] [Revised: 07/23/2024] [Accepted: 07/29/2024] [Indexed: 08/05/2024]
Abstract
Although thermosonication (TS) treatment has been widely used in food sterilization, the viable but non-culturable (VBNC) of bacteria with TS treatment has still concerned potential food safety and public health. The molecular mechanism of VBNC status of bacteria with TS treatment is not clearly known. Therefore, in this study, we used Shewanella putrefaciens, which was a common putrefactive bacteria in aquatic products, to study the VBNC state of bacteria with TS treatment. Firstly, our results revealed that S. putrefaciens still could enter the VBNC state after TS treatments: 50 kHz, 300 W, 30 min ultrasonic treatment and 70 °C heating; Subsequently, we found the VBNC state of S. putrefaciens can resist the damage of TS treatment, such as cell wall break, DNA degradation, etc; Finally, four-dimensional data-independent acquisition-based proteomics showed that under VBNC state, S. putrefaciens upregulated functional proteins to resist TS treatment, such as: ribosomal proteins to accelerate the synthesis of stress proteins to counteract TS treatments, ornithine decarboxylase SpeF and MraY to repair TS treatment-induced damage, etc. Meanwhile, S. putrefaciens downregulates metabolic and transport functional proteins such as dehydrogenase to reduce the metabolism. Importantly, among those proteins, the ribosomal transcriptional regulatory protein family, such as rpsB, etc, may be the key proteins for S. putrefaciens entering VBNC state. This finding can provide some new strategies for preventing VBNC status of bacteria with TS treatment, such as: inhibition of key proteins, etc.
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Affiliation(s)
- Ziwei Jiang
- Key Laboratory of Cold Chain Logistics Technology for Agro-Product, Ministry of Agriculture and Rural Affairs/Institute of Agro-Product Processing and Nuclear Agricultural Technology, Hubei Academy of Agricultural Sciences, Wuhan 430064, China; Hubei Engineering Research Center for Agro-Product Irradiation, Agro-product Processing Research Sub-center of Hubei Innovation Center of Agriculture Science and Technology, Wuhan 430064, China; School of Chemistry and Environmental Engineering, Wuhan Institute of Technology, Wuhan 4300731, China
| | - Yi Wang
- Key Laboratory of Cold Chain Logistics Technology for Agro-Product, Ministry of Agriculture and Rural Affairs/Institute of Agro-Product Processing and Nuclear Agricultural Technology, Hubei Academy of Agricultural Sciences, Wuhan 430064, China; Hubei Engineering Research Center for Agro-Product Irradiation, Agro-product Processing Research Sub-center of Hubei Innovation Center of Agriculture Science and Technology, Wuhan 430064, China
| | - Shunjie Bai
- Key Laboratory of Cold Chain Logistics Technology for Agro-Product, Ministry of Agriculture and Rural Affairs/Institute of Agro-Product Processing and Nuclear Agricultural Technology, Hubei Academy of Agricultural Sciences, Wuhan 430064, China; Hubei Engineering Research Center for Agro-Product Irradiation, Agro-product Processing Research Sub-center of Hubei Innovation Center of Agriculture Science and Technology, Wuhan 430064, China
| | - Chan Bai
- Key Laboratory of Cold Chain Logistics Technology for Agro-Product, Ministry of Agriculture and Rural Affairs/Institute of Agro-Product Processing and Nuclear Agricultural Technology, Hubei Academy of Agricultural Sciences, Wuhan 430064, China; Hubei Engineering Research Center for Agro-Product Irradiation, Agro-product Processing Research Sub-center of Hubei Innovation Center of Agriculture Science and Technology, Wuhan 430064, China
| | - Ziyi Tu
- HuBei Crawfish Industrial Tech Ltd., Qianjiang 433100, China
| | - Hailan Li
- Key Laboratory of Cold Chain Logistics Technology for Agro-Product, Ministry of Agriculture and Rural Affairs/Institute of Agro-Product Processing and Nuclear Agricultural Technology, Hubei Academy of Agricultural Sciences, Wuhan 430064, China; Hubei Engineering Research Center for Agro-Product Irradiation, Agro-product Processing Research Sub-center of Hubei Innovation Center of Agriculture Science and Technology, Wuhan 430064, China
| | - Peng Guo
- Key Laboratory of Cold Chain Logistics Technology for Agro-Product, Ministry of Agriculture and Rural Affairs/Institute of Agro-Product Processing and Nuclear Agricultural Technology, Hubei Academy of Agricultural Sciences, Wuhan 430064, China; Hubei Engineering Research Center for Agro-Product Irradiation, Agro-product Processing Research Sub-center of Hubei Innovation Center of Agriculture Science and Technology, Wuhan 430064, China
| | - Tao Liao
- Key Laboratory of Cold Chain Logistics Technology for Agro-Product, Ministry of Agriculture and Rural Affairs/Institute of Agro-Product Processing and Nuclear Agricultural Technology, Hubei Academy of Agricultural Sciences, Wuhan 430064, China; Hubei Engineering Research Center for Agro-Product Irradiation, Agro-product Processing Research Sub-center of Hubei Innovation Center of Agriculture Science and Technology, Wuhan 430064, China.
| | - Liang Qiu
- Key Laboratory of Cold Chain Logistics Technology for Agro-Product, Ministry of Agriculture and Rural Affairs/Institute of Agro-Product Processing and Nuclear Agricultural Technology, Hubei Academy of Agricultural Sciences, Wuhan 430064, China; Hubei Engineering Research Center for Agro-Product Irradiation, Agro-product Processing Research Sub-center of Hubei Innovation Center of Agriculture Science and Technology, Wuhan 430064, China.
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7
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Koutsoumanis K, Allende A, Alvarez‐Ordóñez A, Bolton D, Bover‐Cid S, Chemaly M, De Cesare A, Herman L, Hilbert F, Lindqvist R, Nauta M, Nonno R, Peixe L, Ru G, Simmons M, Skandamis P, Baker‐Austin C, Hervio‐Heath D, Martinez‐Urtaza J, Caro ES, Strauch E, Thébault A, Guerra B, Messens W, Simon AC, Barcia‐Cruz R, Suffredini E. Public health aspects of Vibrio spp. related to the consumption of seafood in the EU. EFSA J 2024; 22:e8896. [PMID: 39045511 PMCID: PMC11263920 DOI: 10.2903/j.efsa.2024.8896] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/25/2024] Open
Abstract
Vibrio parahaemolyticus, Vibrio vulnificus and non-O1/non-O139 Vibrio cholerae are the Vibrio spp. of highest relevance for public health in the EU through seafood consumption. Infection with V. parahaemolyticus is associated with the haemolysins thermostable direct haemolysin (TDH) and TDH-related haemolysin (TRH) and mainly leads to acute gastroenteritis. V. vulnificus infections can lead to sepsis and death in susceptible individuals. V. cholerae non-O1/non-O139 can cause mild gastroenteritis or lead to severe infections, including sepsis, in susceptible individuals. The pooled prevalence estimate in seafood is 19.6% (95% CI 13.7-27.4), 6.1% (95% CI 3.0-11.8) and 4.1% (95% CI 2.4-6.9) for V. parahaemolyticus, V. vulnificus and non-choleragenic V. cholerae, respectively. Approximately one out of five V. parahaemolyticus-positive samples contain pathogenic strains. A large spectrum of antimicrobial resistances, some of which are intrinsic, has been found in vibrios isolated from seafood or food-borne infections in Europe. Genes conferring resistance to medically important antimicrobials and associated with mobile genetic elements are increasingly detected in vibrios. Temperature and salinity are the most relevant drivers for Vibrio abundance in the aquatic environment. It is anticipated that the occurrence and levels of the relevant Vibrio spp. in seafood will increase in response to coastal warming and extreme weather events, especially in low-salinity/brackish waters. While some measures, like high-pressure processing, irradiation or depuration reduce the levels of Vibrio spp. in seafood, maintaining the cold chain is important to prevent their growth. Available risk assessments addressed V. parahaemolyticus in various types of seafood and V. vulnificus in raw oysters and octopus. A quantitative microbiological risk assessment relevant in an EU context would be V. parahaemolyticus in bivalve molluscs (oysters), evaluating the effect of mitigations, especially in a climate change scenario. Knowledge gaps related to Vibrio spp. in seafood and aquatic environments are identified and future research needs are prioritised.
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8
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Wang J, Huo L, Bian K, He H, Dodd MC, Pinto AJ, Huang CH. Efficacy and Mechanism of Antibiotic Resistance Gene Degradation and Cell Membrane Damage during Ultraviolet Advanced Oxidation Processes. ACS ES&T WATER 2024; 4:2746-2755. [PMID: 38903200 PMCID: PMC11186015 DOI: 10.1021/acsestwater.4c00350] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/24/2024] [Revised: 05/21/2024] [Accepted: 05/23/2024] [Indexed: 06/22/2024]
Abstract
Combinations of UV with oxidants can initiate advanced oxidation processes (AOPs) and enhance bacterial inactivation. However, the effectiveness and mechanisms of UV-AOPs in damaging nucleic acids (e.g., antibiotic resistance genes (ARGs)) and cell integrity represent a knowledge gap. This study comprehensively compared ARG degradation and cell membrane damage under three different UV-AOPs. The extracellular ARG (eARG) removal efficiency followed the order of UV/chlorine > UV/H2O2 > UV/peracetic acid (PAA). Hydroxyl radical (•OH) and reactive chlorine species (RCS) largely contributed to eARG removal, while organic radicals made a minor contribution. For intracellular ARGs (iARGs), UV/H2O2 did not remove better than UV alone due to the scavenging of •OH by cell components, whereas UV/PAA provided a modest synergism, likely due to diffusion of PAA into cells and intracellular •OH generation. Comparatively, UV/chlorine achieved significant synergistic iARG removal, suggesting the critical role of the RCS in resisting cellular scavenging and inactivating ARGs. Additionally, flow cytometry analysis demonstrated that membrane damage was mainly attributed to chlorine oxidation, while the impacts of radicals, H2O2, and PAA were negligible. These results provide mechanistic insights into bacterial inactivation and fate of ARGs during UV-AOPs, and shed light on the suitability of quantitative polymerase chain reaction (qPCR) and flow cytometry in assessing disinfection performance.
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Affiliation(s)
- Junyue Wang
- School
of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, United States
| | - Linxuan Huo
- School
of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, United States
| | - Kaiqin Bian
- School
of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, United States
| | - Huan He
- State
Key Laboratory of Pollution Control and Resource Reuse, Key Laboratory
of Yangtze Water Environment, Ministry of Education, College of Environmental
Science and Engineering, Tongji University, Shanghai 200092, P. R. China
| | - Michael C. Dodd
- Department
of Civil and Environmental Engineering, University of Washington (UW), Seattle, Washington 98195-2700, United States
| | - Ameet J. Pinto
- School
of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, United States
| | - Ching-Hua Huang
- School
of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, United States
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9
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Lin Q, Sheng M, Kang Z, Xu J, Gao Y, Ma S, Xin B, Tan Y. Synergistic and antibiofilm activity of DNase I and glucose oxidase loaded chitosan nanoparticles against dual-species biofilms of Listeria monocytogenes and Salmonella. Int J Biol Macromol 2024; 269:131943. [PMID: 38688332 DOI: 10.1016/j.ijbiomac.2024.131943] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2023] [Revised: 03/28/2024] [Accepted: 04/26/2024] [Indexed: 05/02/2024]
Abstract
Salmonella and Listeria monocytogenes are two of the most common foodborne pathogens in the food industry. They form dual-species biofilms, which have a higher sensitivity to antimicrobial treatment and a greater microbial adhesion. In this experiment, we loaded DNase I and glucose oxidase (GOX) on chitosan nanoparticles (CSNPs) to explore their inhibitory effects on and disruption of dual-species biofilms of Salmonella enterica and L. monocytogenes. Transmission electron microscopy (TEM) showed that CSNP-DNase-GOX and CSNPs were spherical in shape. CSNP-DNase-GOX was shifted and altered compared to the infrared peaks of CSNPs. CSNPs loaded with DNase I and GOX showed an increase in the particle size and an alteration in the polydispersity index (PDI) and the zeta potential. Compared to free DNase I or GOX, DNase I and GOX loaded on CSNPs had higher stability at different temperatures. CSNP-DNase-GOX was more effective in inhibiting dual-species biofilms than CSNP-GOX. Scanning electron microscopy (SEM) and fluorescence microscopy were used to observe the structure of the biofilm, which further illustrated that CSNP-DNase-GOX disrupted the dual-species biofilms of S. enterica and L. monocytogenes.
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Affiliation(s)
- Quan Lin
- College of Food Science and Engineering, Qingdao Agricultural University, Qingdao, China; Shandong Technology Innovation Center of Special Food, Qingdao, China; Qingdao Special Food Research Institute, Qingdao, China
| | - Maokun Sheng
- College of Food Science and Engineering, Qingdao Agricultural University, Qingdao, China; Shandong Technology Innovation Center of Special Food, Qingdao, China; Qingdao Special Food Research Institute, Qingdao, China
| | - Zhaodi Kang
- College of Food Science and Engineering, Qingdao Agricultural University, Qingdao, China; Shandong Technology Innovation Center of Special Food, Qingdao, China; Qingdao Special Food Research Institute, Qingdao, China
| | - Jiaman Xu
- College of Food Science and Engineering, Qingdao Agricultural University, Qingdao, China; Shandong Technology Innovation Center of Special Food, Qingdao, China; Qingdao Special Food Research Institute, Qingdao, China
| | - Yan Gao
- Marine Science Research Institute of Shandong Province (National Oceanographic Center of Qingdao), Qingdao, China
| | - Su Ma
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, China
| | - Bingchang Xin
- Department of Cariology and Endodontology, Qingdao Stomatological Hospital Affiliated to Qingdao University, Qingdao, China
| | - Yulong Tan
- College of Food Science and Engineering, Qingdao Agricultural University, Qingdao, China; Shandong Technology Innovation Center of Special Food, Qingdao, China; Qingdao Special Food Research Institute, Qingdao, China.
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10
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Liu X, Liu S, Wang Y, Shi Y, Chen Q. New insights into the antibiofilm activity and mechanism of Mannosylerythritol Lipid-A against Listeria monocytogenes EGD-e. Biofilm 2024; 7:100201. [PMID: 38779407 PMCID: PMC11108854 DOI: 10.1016/j.bioflm.2024.100201] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2024] [Revised: 04/28/2024] [Accepted: 05/09/2024] [Indexed: 05/25/2024] Open
Abstract
Listeria monocytogenes is one of the leading causative agents of foodborne disease outbreaks worldwide. Herein, the antibiofilm effect and mechanism of Mannosylerythritol Lipid-A against L. monocytogenes EGD-e is reported for the first time. MEL-A effectively attenuated biofilm formation while reducing the viability and motility of bacteria within the biofilm in the early stage, and influenced bacterial adhesion by affecting the secretion of extracellular polysaccharides and eDNA. RT-qPCR revealed that MEL-A significantly suppressed the expression of genes involved in flagellar movement and virulence. Untargeted LC-MS metabolomics indicated that MEL-A affected the fluidity and permeability of cell membranes by significantly upregulating unsaturated fatty acids, lipids and glycoside metabolites, and affected protein biosynthesis, nucleotide metabolism and DNA synthesis and repair by significantly downregulating amino acid metabolism and nucleic acid metabolism. These pathways may constitute the key targets of biofilm formation inhibition by MEL-A. Furthermore, MEL-A showed good removal effects on mature biofilms under different temperatures, different materials and milk. Our data indicated that MEL-A could be used as a novel antibiofilm agent to improve food safety. Our study provides new insights into the possible inhibitory mechanism of MEL-A and the response of L. monocytogenes EGD-e to MEL-A.
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Affiliation(s)
- Xiayu Liu
- Innovation Center of Yangtze River Delta, Zhejiang University, Jiashan, 314100, China
| | - Siyu Liu
- Department of Food Science and Nutrition, Zhejiang University, Hangzhou, 310058, China
- Innovation Center of Yangtze River Delta, Zhejiang University, Jiashan, 314100, China
| | - Yuxi Wang
- Department of Food Science and Nutrition, Zhejiang University, Hangzhou, 310058, China
| | - Ying Shi
- Department of Food Science and Nutrition, Zhejiang University, Hangzhou, 310058, China
| | - Qihe Chen
- Department of Food Science and Nutrition, Zhejiang University, Hangzhou, 310058, China
- Innovation Center of Yangtze River Delta, Zhejiang University, Jiashan, 314100, China
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Luo C, Chen C, Xian X, Cai WF, Yu X, Ye C. The secondary outbreak risk and mechanisms of Microcystis aeruginosa after H 2O 2 treatment. JOURNAL OF HAZARDOUS MATERIALS 2024; 470:134196. [PMID: 38603907 DOI: 10.1016/j.jhazmat.2024.134196] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2024] [Revised: 03/18/2024] [Accepted: 03/31/2024] [Indexed: 04/13/2024]
Abstract
The secondary outbreak of cyanobacteria after algicide treatment has been a serious problem to water ecosystems. Hydrogen peroxide (H2O2) is an algaecide widely used in practice, but similar re-bloom problems are inevitably encountered. Our work found that Microcystis aeruginosa (M. aeruginosa) temporarily hibernates after H2O2 treatment, but there is still a risk of secondary outbreaks. Interestingly, the dormant period was as long as 20 and 28 days in 5 mg L-1 and 20 mg L-1 H2O2 treatment groups, respectively, but the photosynthetic activity was both restored much earlier (within 14 days). Subsequently, a quantitative imaging flow cytometry-based method was constructed and confirmed that the re-bloom had undergone two stages including first recovery and then re-division. The expression of ftsZ and fabZ genes showed that M. aeruginosa had active transcription processes related to cell division protein and fatty acid synthesis during the dormancy stat. Furthermore, metabolomics suggested that the recovery of M. aeruginosa was mainly by activating folate and salicylic acid synthesis pathways, which promoted environmental stress resistance, DNA synthesis, and cell membrane repair. This study reported the comprehensive mechanisms of secondary outbreak of M. aeruginosa after H2O2 treatment. The findings suggest that optimizing the dosage and frequency of H2O2, as well as exploring the potential use of salicylic acid and folic acid inhibitors, could be promising directions for future algal control strategies.
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Affiliation(s)
- Chen Luo
- Fujian Key Laboratory of Coastal Pollution Prevention and Control, College of the Environment & Ecology, Xiamen University, Xiamen 361102, China
| | - Chenlan Chen
- Fujian Key Laboratory of Coastal Pollution Prevention and Control, College of the Environment & Ecology, Xiamen University, Xiamen 361102, China
| | - Xuanxuan Xian
- Ecological &Environment Monitoring Center of Zhejiang Province, Hangzhou 310012, China
| | - Wei-Feng Cai
- Xiamen Cancer Center, The First Affiliated Hospital of Xiamen University, School of Medicine, Xiamen University, Xiamen 361103. China
| | - Xin Yu
- Fujian Key Laboratory of Coastal Pollution Prevention and Control, College of the Environment & Ecology, Xiamen University, Xiamen 361102, China.
| | - Chengsong Ye
- Fujian Key Laboratory of Coastal Pollution Prevention and Control, College of the Environment & Ecology, Xiamen University, Xiamen 361102, China.
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Vigil-Cuate LK, Avila-Reyes SV, Camacho-Díaz BH, Hernández-Sánchez H, Osorio-Díaz P, Jiménez-Aparicio AR, Robert P, Arenas-Ocampo ML. Effect of Agavins and Agave Syrup Use in the Formulation of a Synbiotic Gelatin Gummy with Microcapsules of Saccharomyces Boulardii. Gels 2024; 10:299. [PMID: 38786216 PMCID: PMC11121532 DOI: 10.3390/gels10050299] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2024] [Revised: 04/19/2024] [Accepted: 04/23/2024] [Indexed: 05/25/2024] Open
Abstract
Agavins are reserve carbohydrates found in agave plants; they present texture-modifying properties and prebiotic capacity by increasing the viability of the intestinal microbiota. Through its hydrolysis, agave syrup (AS) can be obtained and can be used as a sweetener in food matrices. The objective of this work was to evaluate the effect of the variation in the content of agavins and AS on the physical, structural, and viability properties of Saccharomyces boulardii encapsulates incorporated into gelatin gummies. An RSM was used to obtain an optimized formulation of gelatin gummies. The properties of the gel in the gummy were characterized by a texture profile analysis and Aw. The humidity and sugar content were determined. A sucrose gummy was used as a control for the variable ranges. Alginate microcapsules containing S. boulardii were added to the optimized gummy formulation to obtain a synbiotic gummy. The viability of S. boulardii and changes in the structure of the alginate gel of the microcapsules in the synbiotic gummy were evaluated for 24 days by image digital analysis (IDA). The agavins and agave syrup significantly affected the texture properties (<1 N) and the Aw (>0.85). The IDA showed a change in the gel network and an increase in viability by confocal microscopy from day 18. The number of pores in the gel increased, but their size decreased with an increase in the number of S. boulardii cells. Agavins and cells alter the structure of capsules in gummies without affecting their viability.
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Affiliation(s)
- Liliana K. Vigil-Cuate
- Instituto Politécnico Nacional-CEPROBI, Carretera Yautepec-Jojutla, Km.6 calle CEPROBI No.8, Colonia San Isidro, Yautepec C.P. 62730, Mexico; (L.K.V.-C.); (B.H.C.-D.); (P.O.-D.); (A.R.J.-A.)
| | - Sandra V. Avila-Reyes
- CONAHCyT-Instituto Politécnico Nacional-CEPROBI, Carretera Yautepec-Jojutla, Km.6 calle CEPROBI No.8, Colonia San Isidro, Yautepec C.P. 62730, Mexico
| | - Brenda H. Camacho-Díaz
- Instituto Politécnico Nacional-CEPROBI, Carretera Yautepec-Jojutla, Km.6 calle CEPROBI No.8, Colonia San Isidro, Yautepec C.P. 62730, Mexico; (L.K.V.-C.); (B.H.C.-D.); (P.O.-D.); (A.R.J.-A.)
| | - Humberto Hernández-Sánchez
- Departamento de Ingeniería Bioquímica, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, Unidad Profesional Adolfo López Mateos, Mexico City C.P. 07738, Mexico;
| | - Perla Osorio-Díaz
- Instituto Politécnico Nacional-CEPROBI, Carretera Yautepec-Jojutla, Km.6 calle CEPROBI No.8, Colonia San Isidro, Yautepec C.P. 62730, Mexico; (L.K.V.-C.); (B.H.C.-D.); (P.O.-D.); (A.R.J.-A.)
| | - Antonio R. Jiménez-Aparicio
- Instituto Politécnico Nacional-CEPROBI, Carretera Yautepec-Jojutla, Km.6 calle CEPROBI No.8, Colonia San Isidro, Yautepec C.P. 62730, Mexico; (L.K.V.-C.); (B.H.C.-D.); (P.O.-D.); (A.R.J.-A.)
| | - Paz Robert
- Departamento de Ciencias de los Alimentos y Tecnología Química, Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, Santos Dumont 964, Independencia, Santiago C.P. 8380494, Chile;
| | - Martha L. Arenas-Ocampo
- Instituto Politécnico Nacional-CEPROBI, Carretera Yautepec-Jojutla, Km.6 calle CEPROBI No.8, Colonia San Isidro, Yautepec C.P. 62730, Mexico; (L.K.V.-C.); (B.H.C.-D.); (P.O.-D.); (A.R.J.-A.)
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Debnath A, Miyoshi SI. Effect of physicochemical and microbiological factors on the development of viable but non-culturable and resuscitation states of Vibrio cholerae. Arch Microbiol 2024; 206:224. [PMID: 38642319 DOI: 10.1007/s00203-024-03956-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2024] [Revised: 04/06/2024] [Accepted: 04/08/2024] [Indexed: 04/22/2024]
Abstract
BACKGROUND Vibrio cholerae can endure harsh environmental conditions by transitioning into viable but non-culturable (VBNC) form and resuscitate upon return of appropriate conditions. METHOD In this study, we assessed the impact of physicochemical and microbiological factors, on the development of low temperature-induced VBNC state and subsequent recovery by temperature upshift. RESULTS In estuarine water, Vibrio cholerae exhibits a slower decline in culturability over a period of 77 days as compared to 10 days in fresh water. When variable cell numbers from different growth phases were used for VBNC induction, it was observed that the higher inoculum size (106-107 cfu ml-1) from the late log phase culture appears to be crucial for entering the VBNC state. Conversely, starved cells could enter the VBNC state with an initial inoculum of 104-105 cfu ml-1, followed by resuscitation as well. The addition of glucose, GlcNAc and mannitol differentially affects progression into VBNC, while the addition of tryptone, yeast extract and casamino acid facilitated early entry into the VBNC state and shortened the length of the recovery period. CONCLUSION Altogether these findings demonstrated that the ionic strength of water, inoculum size and the availability of nutrients played distinct roles during VBNC induction and resuscitation.
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Affiliation(s)
- Anusuya Debnath
- Dentistry and Pharmaceutical Sciences, Okayama University, 1-1-1, Tsushimanaka, Kita-ku, 700-8530, Japan.
- Department of Biotechnology, Brainware University, Kolkata, India.
| | - Shin-Ichi Miyoshi
- Dentistry and Pharmaceutical Sciences, Okayama University, 1-1-1, Tsushimanaka, Kita-ku, 700-8530, Japan
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Gricajeva A, Buchovec I, Kalėdienė L, Badokas K, Vitta P. Evaluation of visible light and natural photosensitizers against Staphylococcus epidermidis and Staphylococcus saprophyticus planktonic cells and biofilm. Heliyon 2024; 10:e28811. [PMID: 38596007 PMCID: PMC11002230 DOI: 10.1016/j.heliyon.2024.e28811] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2023] [Revised: 03/21/2024] [Accepted: 03/25/2024] [Indexed: 04/11/2024] Open
Abstract
Antimicrobial photoinactivation (API) has shown some promise in potentially treating different nosocomial bacterial infections, however, its application on staphylococci, especially other than Staphylococcus aureus or methicillin-resistant S. aureus (MRSA) species is still limited. Although S. aureus is a well-known and important nosocomial pathogen, several other species of the genus, particularly coagulase-negative Staphylococcus (CNS) species such as Staphylococcus epidermidis and Staphylococcus saprophyticus, can also cause healthcare-associated infections and foodborne intoxications. CNS are often involved in resilient biofilm formation on medical devices and can cause infections in patients with compromised immune systems or those undergoing invasive procedures. In this study, the effects of chlorophyllin and riboflavin-mediated API on S. epidermidis and S. saprophyticus planktonic cells and biofilm are demonstrated for the first time. Based on the residual growth determination and metabolic reduction ability changes, higher inactivating efficiency of chlorophyllin-mediated API was determined against the planktonic cells of both tested species of bacteria and against S. saprophyticus biofilm. Some insights on whether aqueous solutions of riboflavin and chlorophyllin, when illuminated with optimal exciting wavelength (440 nm and 402 nm, respectively) generate O2-•, are also provided in this work.
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Affiliation(s)
- Alisa Gricajeva
- Institute of Biosciences, Department of Microbiology and Biotechnology, Life Sciences Center, Vilnius University, Sauletekio avenue 7, LT-10257, Vilnius, Lithuania
| | - Irina Buchovec
- Institute of Photonics and Nanotechnology, Faculty of Physics, Sauletekio avenue 3, LT-10257, Vilnius University, Vilnius, Lithuania
| | - Lilija Kalėdienė
- Institute of Biosciences, Department of Microbiology and Biotechnology, Life Sciences Center, Vilnius University, Sauletekio avenue 7, LT-10257, Vilnius, Lithuania
| | - Kazimieras Badokas
- Institute of Photonics and Nanotechnology, Faculty of Physics, Sauletekio avenue 3, LT-10257, Vilnius University, Vilnius, Lithuania
| | - Pranciškus Vitta
- Institute of Photonics and Nanotechnology, Faculty of Physics, Sauletekio avenue 3, LT-10257, Vilnius University, Vilnius, Lithuania
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15
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Ji C, Guo J, Ma Y, Xu X, Zang T, Liu S, An Z, Yang M, He X, Zheng W. Application Progress of Culturomics in the Isolated Culture of Rhizobacteria: A Review. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2024; 72:7586-7595. [PMID: 38530921 DOI: 10.1021/acs.jafc.3c08885] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/28/2024]
Abstract
Comprehending the structure and function of rhizobacteria components and their regulation are crucial for sustainable agricultural management. However, obtaining comprehensive species information for most bacteria in the natural environment, particularly rhizobacteria, presents a challenge using traditional culture methods. To obtain diverse and pure cultures of rhizobacteria, this study primarily reviews the evolution of rhizobacteria culturomics and associated culture methods. Furthermore, it explores new strategies for enhancing the application of culturomics, providing valuable insights into efficiently enriching and isolate target bacterial strains/groups from the environment. The findings will help improve rhizobacteria's culturability and enrich the functional bacterial library.
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Affiliation(s)
- Chao Ji
- Tianjin Key Laboratory of Animal and Plant Resistance, College of Life Sciences, Tianjin Normal University, Tianjin, 300387, China
| | - Junli Guo
- Tianjin Key Laboratory of Animal and Plant Resistance, College of Life Sciences, Tianjin Normal University, Tianjin, 300387, China
| | - Ying Ma
- Tianjin Key Laboratory of Animal and Plant Resistance, College of Life Sciences, Tianjin Normal University, Tianjin, 300387, China
| | - Xiangfu Xu
- Tianjin Key Laboratory of Animal and Plant Resistance, College of Life Sciences, Tianjin Normal University, Tianjin, 300387, China
| | - Tongyu Zang
- Tianjin Key Laboratory of Animal and Plant Resistance, College of Life Sciences, Tianjin Normal University, Tianjin, 300387, China
| | - Sentao Liu
- Tianjin Key Laboratory of Animal and Plant Resistance, College of Life Sciences, Tianjin Normal University, Tianjin, 300387, China
| | - Zhenzhen An
- Tianjin Key Laboratory of Animal and Plant Resistance, College of Life Sciences, Tianjin Normal University, Tianjin, 300387, China
| | - Min Yang
- State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan, National Engineering Research Center for Applied Technology of Agricultural Biodiversity, College of Plant Protection, Yunnan Agricultural University, Kunming, Yunnan 650201, China
| | - Xiahong He
- State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan, National Engineering Research Center for Applied Technology of Agricultural Biodiversity, College of Plant Protection, Yunnan Agricultural University, Kunming, Yunnan 650201, China
- Key Laboratory for Forest Resources Conservation and Utilization in the Southwest Mountains of China, Ministry of Education, Southwest Landscape Architecture Engineering Research Center of National Forestry and Grassland Administration, Southwest Forestry University, Kunming, Yunnan 650224, China
| | - Wenjie Zheng
- Tianjin Key Laboratory of Animal and Plant Resistance, College of Life Sciences, Tianjin Normal University, Tianjin, 300387, China
- State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan, National Engineering Research Center for Applied Technology of Agricultural Biodiversity, College of Plant Protection, Yunnan Agricultural University, Kunming, Yunnan 650201, China
- Key Laboratory for Forest Resources Conservation and Utilization in the Southwest Mountains of China, Ministry of Education, Southwest Landscape Architecture Engineering Research Center of National Forestry and Grassland Administration, Southwest Forestry University, Kunming, Yunnan 650224, China
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16
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Shi Y, Wen T, Zhao F, Hu J. Bacteriostasis of nisin against planktonic and biofilm bacteria: Its mechanism and application. J Food Sci 2024; 89:1894-1916. [PMID: 38477236 DOI: 10.1111/1750-3841.17001] [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: 12/16/2023] [Revised: 01/27/2024] [Accepted: 02/09/2024] [Indexed: 03/14/2024]
Abstract
Food safety incidents caused by bacterial contamination have always been one of the public safety issues of social concern. Planktonic cells, viable but non-culturable (VBNC) cells, and biofilm cells of bacteria can coexist in food or food processing, posing more serious challenges to public health and safety by increasing bacterial survival and difficulty in detection. As a non-toxic, no side effect, and highly effective bacteriostatic substance, nisin has received wide attention from researchers. In this review, we summarized the species and biosynthesis of nisin, the effects of nisin alone or in combination with other treatments on planktonic and biofilm cells, and its applications in the fields of food, feed, and medicine by consulting numerous studies. Meanwhile, the mechanism of nisin on planktonic and biofilm cells was proposed based on existing researches. Nisin not only has antibacterial activity against most G+ bacteria but also exhibits a bacteriostatic effect on G- bacteria when combined with other antibacterial treatments. In addition to planktonic cells, nisin also has significant effects on bacterial cells in biofilms by changing the thickness, density, and composition of biofilms. Based on the three action processes of nisin on biofilms, we summarized the changes of bacteria in biofilms, including the causes of bacterial death and the formation of the VBNC state. We consider that research on the relationship between nisin and VBNC state should be strengthened.
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Affiliation(s)
- Ying Shi
- College of Food Science and Engineering, Jilin University, Changchun, P. R. China
| | - Tao Wen
- College of Food Science and Engineering, Jilin University, Changchun, P. R. China
| | - Feng Zhao
- College of Food Science and Engineering, Jilin University, Changchun, P. R. China
| | - Jia Hu
- College of Food Science and Engineering, Jilin University, Changchun, P. R. China
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Yang H, He D, Fan L, Cheng F, Zhou Y, Lei Y, Zhang YN, Yang X, Qu J. Evaluating the Impact of Cl 2•- Generation on Antibiotic-Resistance Contamination Removal via UV/Peroxydisulfate. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2024; 58:5578-5588. [PMID: 38477971 DOI: 10.1021/acs.est.3c09952] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/14/2024]
Abstract
The removal of antibiotic-resistant bacteria (ARB) and antibiotic-resistance genes (ARGs) using sulfate anion radical (SO4•-)-based advanced oxidation processes has gained considerable attention recently. However, immense uncertainties persist in technology transfer. Particularly, the impact of dichlorine radical (Cl2•-) generation during SO4•--mediated disinfection on ARB/ARGs removal remains unclear, despite the Cl2•- concentration reaching levels notably higher than those of SO4•- in certain SO4•--based procedures applied to secondary effluents, hospital wastewaters, and marine waters. The experimental results of this study reveal a detrimental effect on the disinfection efficiency of tetracycline-resistant Escherichia coli (Tc-ARB) during SO4•--mediated treatment owing to Cl2•- generation. Through a comparative investigation of the distinct inactivation mechanisms of Tc-ARB in the Cl2•-- and SO4•--mediated disinfection processes, encompassing various perspectives, we confirm that Cl2•- is less effective in inducing cellular structural damage, perturbing cellular metabolic activity, disrupting antioxidant enzyme system, damaging genetic material, and inducing the viable but nonculturable state. Consequently, this diminishes the disinfection efficiency of SO4•--mediated treatment owing to Cl2•- generation. Importantly, the results indicate that Cl2•- generation increases the potential risk associated with the dark reactivation of Tc-ARB and the vertical gene transfer process of tetracycline-resistant genes following SO4•--mediated disinfection. This study underscores the undesired role of Cl2•- for ARB/ARGs removal during the SO4•--mediated disinfection process.
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Affiliation(s)
- Hao Yang
- School of Environment, Northeast Normal University, Changchun, Jilin 130117, China
| | - Dongyang He
- School of Environment, Northeast Normal University, Changchun, Jilin 130117, China
| | - Linyi Fan
- School of Environment, Northeast Normal University, Changchun, Jilin 130117, China
| | - Fangyuan Cheng
- School of Environment, Northeast Normal University, Changchun, Jilin 130117, China
| | - Yangjian Zhou
- School of Environmental Science and Engineering, Sun Yat-sen University, Guangzhou 510275, China
| | - Yu Lei
- Key Laboratory of Photochemistry, Institute of Chemistry Chinese Academy of Sciences, Beijing National Laboratory for Molecular Sciences, Beijing 100190, P. R. China
| | - Ya-Nan Zhang
- School of Environment, Northeast Normal University, Changchun, Jilin 130117, China
| | - Xin Yang
- School of Environmental Science and Engineering, Sun Yat-sen University, Guangzhou 510275, China
| | - Jiao Qu
- School of Environment, Northeast Normal University, Changchun, Jilin 130117, China
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18
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Ekundayo TC, Ijabadeniyi OA. Global and regional prevalence of Cronobacter sakazakii in powdered milk and flour. Sci Rep 2024; 14:6865. [PMID: 38514864 PMCID: PMC10957878 DOI: 10.1038/s41598-024-57586-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2023] [Accepted: 03/19/2024] [Indexed: 03/23/2024] Open
Abstract
Cronobacter sakazakii (Cz) infections linked with powdered milk/flour (PMF) are on the increase in recent times. The current study aimed at assessing worldwide and regional prevalence of Cz in PMF. Cz-PMF-directed data were conscientiously mined in four mega-databases via topic-field driven PRISMA protocol without any restriction. Bivariate analysis of datasets was conducted and then fitted to random-intercept logistic mixed-effects regressions with leave-one-study-out-cross-validation (LOSOCV). Small-study effects were assayed via Egger's regression tests. Contributing factors to Cz contamination/detection in PMF were determined using 1000-permutation-bootstrapped meta-regressions. A total of 3761 records were found out of which 68 studies were included. Sample-size showed considerable correlation with Cz positivity (r = 0.75, p = 2.5e-17), Milkprod2020 (r = 0.33, p = 1.820e-03), and SuDI (r = - 0.30, p = 4.11e-03). The global prevalence of Cz in PMF was 8.39% (95%CI 6.06-11.51, PI: 0.46-64.35) with LOSOCV value of 7.66% (6.39-9.15; PI: 3.10-17.70). Cz prevalence in PMF varies significantly (p < 0.05) with detection methods, DNA extraction method, across continents, WHO regions, and world bank regions. Nation, detection method, world bank region, WHO region, and sample size explained 53.88%, 19.62%, 19.03%, 15.63%, and 9.22% of the true differences in the Cz prevalence in PMF, respectively. In conclusion, the results indicated that national will power in the monitoring and surveillance of Cz in PMF matched with adequate sample size and appropriate detection methods will go a long way in preventing Cz contamination and infections.
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Affiliation(s)
- Temitope C Ekundayo
- Department of Biotechnology and Food Science, Durban University of Technology, Steve Biko Campus, Steve Biko Rd, Musgrave, Berea, Durban, South Africa.
| | - Oluwatosin A Ijabadeniyi
- Department of Biotechnology and Food Science, Durban University of Technology, Steve Biko Campus, Steve Biko Rd, Musgrave, Berea, Durban, South Africa
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Hawer H, Burmester R, Sonnenberg N, Weiß K. Detection of endotoxins from selected drinking water microbiota using an LAL-based assay and its implications for human health. JOURNAL OF WATER AND HEALTH 2024; 22:290-295. [PMID: 38421623 PMCID: wh_2024_207 DOI: 10.2166/wh.2024.207] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/02/2024]
Abstract
Endotoxins are pyrogenic lipopolysaccharides from Gram-negative bacteria that are known to induce fever, septic shock, and multiple organ failure, posing a substantial risk to human health. Drinking water systems are especially prone to home microbiomes containing a large variety of Gram-negative bacteria. Consumption of water from these systems in developed countries is generally regarded as non-hazardous to humans due to the low number of non-pathogenic bacterial cells per milliliter and oral admission. To assess potential risks posed by endotoxins in drinking water systems, we conducted a conventional microbiological investigation on a local community water system in the north of Germany and mined the resulting data to investigate the endotoxin contents of some of the most abundant microbiota found during these analyses. Using a Limulus amoebocyte lysate (LAL) -based endotoxin detection method, average normalized endotoxin content was determined. Although the average culturable amounts of microbiota in the drinking water system were insufficient to exert endotoxin levels critical to human health, peaks and acute contaminations may pose substantial health risks.
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Affiliation(s)
- Harmen Hawer
- Panpharma GmbH, Bunsenstraße 4, 22946, Trittau, Germany E-mail:
| | | | | | - Katja Weiß
- Panpharma GmbH, Bunsenstraße 4, 22946, Trittau, Germany
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20
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Zou Y, Li X, Mao Y, Song W, Liu Q. Enhanced Biofilm Formation by Tetracycline in a Staphylococcus aureus Naturally Lacking ica Operon and atl. Microb Drug Resist 2024; 30:82-90. [PMID: 38252794 DOI: 10.1089/mdr.2023.0186] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2024] Open
Abstract
Staphylococcus aureus is a major, widespread pathogen, and its biofilm-forming characteristics make it even more difficult to eliminate by biocides. Tetracycline (TCY) is a major broad-spectrum antibiotic, the residues of which can cause deleterious health impacts, and subinhibitory concentrations of TCY have the potential to increase biofilm formation in S. aureus. In this study, we showed how the biofilm formation of S. aureus 123786 is enhanced in the presence of TCY at specific subinhibitory concentrations. S. aureus 123786 used in this study was identified as Staphylococcal Cassette Chromosome mec III, sequence type239 and naturally lacking ica operon and atl gene. Two assays were performed to quantify the formation of S. aureus biofilm. In the crystal violet (CV) assay, the absorbance values of biofilm stained with CV at optical density (OD)540 nm increased after 8 and 16 hr of incubation when the concentration of TCY was 1/2 minimum inhibitory concentration (MIC), whereas at the concentration of 1/16 MIC, the absorbance values increased after 16 and 24 hr of incubation. In tetrazolium salt reduction assay, the absorbance value at OD490 nm of S. aureus 123786 biofilms mixed with 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium solution increased after 8 hr when the concentration of TCY was 1/4 MIC, which may be correlated with the higher proliferation and maturation of biofilm. In conclusion, the biofilm formation of S. aureus 123786 could be enhanced in the presence of TCY at specific subinhibitory concentrations.
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Affiliation(s)
- Yimin Zou
- Key Laboratory of Respiratory Disease of Zhejiang Province, Department of Respiratory and Critical Care Medicine, Second Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou, China
| | - Xuejie Li
- Guangdong Province Key Laboratory for Green Processing of Natural Products and Product Safety, Engineering Research Center of Starch and Vegetable Protein Processing Ministry of Education, School of Food Science and Engineering, South China University of Technology, Guangzhou, China
| | - Yanxiong Mao
- Key Laboratory of Respiratory Disease of Zhejiang Province, Department of Respiratory and Critical Care Medicine, Second Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou, China
| | - Wenjuan Song
- Department of Economics, School of Economics and Management, Zhejiang Sci-Tech University, Hangzhou, China
| | - Qing Liu
- Key Laboratory of Respiratory Disease of Zhejiang Province, Department of Respiratory and Critical Care Medicine, Second Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou, China
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Winter H, Wagner R, Ehlbeck J, Urich T, Schnabel U. Deep Impact: Shifts of Native Cultivable Microbial Communities on Fresh Lettuce after Treatment with Plasma-Treated Water. Foods 2024; 13:282. [PMID: 38254583 PMCID: PMC10815073 DOI: 10.3390/foods13020282] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2023] [Revised: 12/18/2023] [Accepted: 01/10/2024] [Indexed: 01/24/2024] Open
Abstract
Foods consumed raw, such as lettuce, can host food-borne human-pathogenic bacteria. In the worst-case, these diseases cause to death. To limit illness and industrial losses, one innovative sanitation method is non-thermal plasma, which offers an extremely efficient reduction of living microbial biomass. Unfortunately, the total viable count (TVC), one of the most common methods for quantifying antimicrobial effects, provides no detailed insights into the composition of the surviving microbial community after treatment. To address this information gap, different special agars were used to investigate the reduction efficiency of plasma-treated water (PTW) on different native cultivable microorganisms. All tested cultivable microbial groups were reduced using PTW. Gram-negative bacteria showed a reduction of 3.81 log10, and Gram-positive bacteria showed a reduction of 3.49 log10. Fungi were reduced by 3.89 log10. These results were further validated using a live/dead assay. MALDI-ToF (matrix-assisted laser-desorption-ionization time-of-flight)-based determination was used for a diversified overview. The results demonstrated that Gram-negative bacteria were strongly reduced. Interestingly, Gram-positive bacteria and fungi were reduced by nearly equal amounts, but could still recover from PTW treatment. MALDI-ToF mainly identified Pseudomonas spp. and groups of Bacillus on the tested lettuce. These results indicate that the PTW treatment could efficiently achieve a ubiquitous, spectrum-wide reduction of microbial life.
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Affiliation(s)
- Hauke Winter
- Leibniz Institute for Plasma Science and Technology (INP), Felix-Hausdorff-Strasse 2, 17489 Greifswald, Germany; (H.W.); (R.W.); (J.E.)
- Institute of Microbiology, Center for Functional Genomics of Microbes, University of Greifswald, 17489 Greifswald, Germany;
| | - Robert Wagner
- Leibniz Institute for Plasma Science and Technology (INP), Felix-Hausdorff-Strasse 2, 17489 Greifswald, Germany; (H.W.); (R.W.); (J.E.)
| | - Jörg Ehlbeck
- Leibniz Institute for Plasma Science and Technology (INP), Felix-Hausdorff-Strasse 2, 17489 Greifswald, Germany; (H.W.); (R.W.); (J.E.)
| | - Tim Urich
- Institute of Microbiology, Center for Functional Genomics of Microbes, University of Greifswald, 17489 Greifswald, Germany;
| | - Uta Schnabel
- Leibniz Institute for Plasma Science and Technology (INP), Felix-Hausdorff-Strasse 2, 17489 Greifswald, Germany; (H.W.); (R.W.); (J.E.)
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Xu Z, Deng Y. Editorial: Community series in emerging frontiers in the formation of viable but non-culturable microorganisms and biofilms during food processing, volume II. Front Microbiol 2023; 14:1306559. [PMID: 37942079 PMCID: PMC10628741 DOI: 10.3389/fmicb.2023.1306559] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2023] [Accepted: 10/09/2023] [Indexed: 11/10/2023] Open
Affiliation(s)
- Zhenbo Xu
- Department of Laboratory Medicine, The Second Affiliated Hospital of Shantou University Medical College, Shantou, China
| | - Yang Deng
- College of Food Science and Engineering, Qingdao Agricultural University, Qingdao, China
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23
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Liang J, Huang TY, Li X, Gao Y. Germicidal effect of intense pulsed light on Pseudomonas aeruginosa in food processing. Front Microbiol 2023; 14:1247364. [PMID: 37692381 PMCID: PMC10484712 DOI: 10.3389/fmicb.2023.1247364] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2023] [Accepted: 08/08/2023] [Indexed: 09/12/2023] Open
Abstract
Background Pseudomonas aeruginosa (P. aeruginosa) can cause serious infections in many parts of the body and is also an underestimated foodborne pathogen. Intense pulsed light sterilization is recognized for its high sterilization efficiency, flexible and safe operation and ease of installation on production lines, which makes up for the shortcomings of several other physical sterilization technologies. Methods This experiment studied the killing efficiency of different capacitances (650 μF, 470 μF, and 220 μF) of intense pulsed light on foodborne pathogenic microorganisms P. aeruginosa in the models of liquid food models, 96-well cell plates, and polycarbonate membrane models at room temperature (25°C) and refrigerated (4°C) environments to provide data to support the application of IPL sterilization devices in food processing. Results The IPL was very effective in killing P. aeruginosa in the planktonic state as well as in the early and mature biofilm states, meeting target kill rates of 100%, 99.99%, and 94.33% for a given number of exposures. The biofilms formed in the polycarbonate membrane model and the 96-well plate model were more resistant to killing compared to the planktonic state. To achieve the same bactericidal effect, the number of flashes increased with decreasing capacitance. Conclusion The bactericidal effect of IPL on P. aeruginosa was significantly influenced by the state of the bacterium. The larger the capacitance the higher the number of pulses and the better the sterilization effect on P. aeruginosa.
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Affiliation(s)
- Jinglong Liang
- College of Light Industry and Food Technology, Zhongkai University of Agriculture and Engineering, Guangzhou, China
- Guangdong Provincial Key Laboratory of Lingnan Specialty Food Science and Technology, Zhongkai University of Agriculture and Engineering, Guangzhou, China
- Key Laboratory of Green Processing and Intelligent Manufacturing of Lingnan Specialty Food, Ministry of Agriculture, Zhongkai University of Agriculture and Engineering, Guangzhou, China
| | - Teng Yi Huang
- Department of Diagnostics, Second Affiliated Hospital of Shantou University Medical College, Shantou, China
| | - Xuejie Li
- Guangdong Province Key Laboratory for Green Processing of Natural Products and Product Safety, School of Food Science and Engineering, Engineering Research Center of Starch and Vegetable Protein Processing Ministry of Education, South China University of Technology, Guangzhou, China
- Research Institute for Food Nutrition and Human Health, Guangzhou, China
| | - Yan Gao
- Department of Genetics, Genomics, and Informatics, University of Tennessee Health Science Center, Memphis, TN, United States
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Zambrano-Romero A, Ramirez-Villacis DX, Barriga-Medina N, Sierra-Alvarez R, Trueba G, Ochoa-Herrera V, Leon-Reyes A. Comparative Methods for Quantification of Sulfate-Reducing Bacteria in Environmental and Engineered Sludge Samples. BIOLOGY 2023; 12:985. [PMID: 37508415 PMCID: PMC10375983 DOI: 10.3390/biology12070985] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/02/2023] [Revised: 06/28/2023] [Accepted: 07/06/2023] [Indexed: 07/30/2023]
Abstract
This study aimed to compare microscopic counting, culture, and quantitative or real-time PCR (qPCR) to quantify sulfate-reducing bacteria in environmental and engineered sludge samples. Four sets of primers that amplified the dsrA and apsA gene encoding the two key enzymes of the sulfate-reduction pathway were initially tested. qPCR standard curves were constructed using genomic DNA from an SRB suspension and dilutions of an enriched sulfate-reducing sludge. According to specificity and reproducibility, the DSR1F/RH3-dsr-R primer set ensured a good quantification based on dsrA gene amplification; however, it exhibited inconsistencies at low and high levels of SRB concentrations in environmental and sulfate-reducing sludge samples. Ultimately, we conducted a qPCR method normalized to dsrA gene copies, using a synthetic double-stranded DNA fragment as a calibrator. This method fulfilled all validation criteria and proved to be specific, accurate, and precise. The enumeration of metabolically active SRB populations through culture methods differed from dsrA gene copies but showed a plausible positive correlation. Conversely, microscopic counting had limitations due to distinguishing densely clustered organisms, impacting precision. Hence, this study proves that a qPCR-based method optimized with dsrA gene copies as a calibrator is a sensitive molecular tool for the absolute enumeration of SRB populations in engineered and environmental sludge samples.
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Affiliation(s)
- Aracely Zambrano-Romero
- Instituto de Microbiología, Universidad San Francisco de Quito USFQ, Campus Cumbayá, Diego de Robles y Vía Interoceánica, Quito 17-1200-841, Ecuador
| | - Dario X Ramirez-Villacis
- Instituto de Microbiología, Universidad San Francisco de Quito USFQ, Campus Cumbayá, Diego de Robles y Vía Interoceánica, Quito 17-1200-841, Ecuador
- Colegio de Ciencias e Ingeniería, Universidad San Francisco de Quito USFQ, Campus Cumbayá, Diego de Robles s/n y Vía Interoceánica, Quito 17-1200-841, Ecuador
- Laboratorio de Biotecnología Agrícola y de Alimentos, Ingeniería en Agronomía, Colegio de Ciencias e Ingenierías, Universidad San Francisco de Quito USFQ, Campus Cumbayá, Diego de Robles y Vía Interoceánica, Quito 17-1200-841, Ecuador
| | - Noelia Barriga-Medina
- Colegio de Ciencias e Ingeniería, Universidad San Francisco de Quito USFQ, Campus Cumbayá, Diego de Robles s/n y Vía Interoceánica, Quito 17-1200-841, Ecuador
- Laboratorio de Biotecnología Agrícola y de Alimentos, Ingeniería en Agronomía, Colegio de Ciencias e Ingenierías, Universidad San Francisco de Quito USFQ, Campus Cumbayá, Diego de Robles y Vía Interoceánica, Quito 17-1200-841, Ecuador
| | - Reyes Sierra-Alvarez
- Department of Chemical and Environmental Engineering, The University of Arizona, P.O. Box 210011, Tucson, AZ 85721-0011, USA
| | - Gabriel Trueba
- Instituto de Microbiología, Universidad San Francisco de Quito USFQ, Campus Cumbayá, Diego de Robles y Vía Interoceánica, Quito 17-1200-841, Ecuador
| | - Valeria Ochoa-Herrera
- Colegio de Ciencias e Ingeniería, Universidad San Francisco de Quito USFQ, Campus Cumbayá, Diego de Robles s/n y Vía Interoceánica, Quito 17-1200-841, Ecuador
- Department of Environmental Sciences and Engineering, Gillings School of Global Public Health, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599-3280, USA
| | - Antonio Leon-Reyes
- Colegio de Ciencias e Ingeniería, Universidad San Francisco de Quito USFQ, Campus Cumbayá, Diego de Robles s/n y Vía Interoceánica, Quito 17-1200-841, Ecuador
- Laboratorio de Biotecnología Agrícola y de Alimentos, Ingeniería en Agronomía, Colegio de Ciencias e Ingenierías, Universidad San Francisco de Quito USFQ, Campus Cumbayá, Diego de Robles y Vía Interoceánica, Quito 17-1200-841, Ecuador
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599-3280, USA
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