Plastics have quickly become an integral part of modern life. Due to excessive production and improper waste disposal, they are recognized as contaminants present in practically all habitat types. Although there are several polymers, polyethylene terephthalate (PET) is of particular concern due to its abundance in the environment. There is a need for a solution that is both cost-effective and ecologically friendly to address this pollutant. The use of microbial depolymerizing enzymes could offer a biological avenue for plastic degradation, though the full potential of these enzymes is yet to be uncovered. The purpose of this study was to use (1) plate-based screening methods to investigate the plastic degradation potential of marine bacteria from the order Enterobacterales collected from various organismal and environmental sources, and (2) perform genome-based analysis to identify polyesterases potentially related to PET degradation. 126 bacterial isolates were obtained from the strain collection of RD3, Research Unit Marine Symbioses-GEOMAR-and sequentially tested for esterase and polyesterase activity, in combination here referred to as PETase-like activity. The results show that members of the microbial families Alteromonadaceae, Shewanellaceae, and Vibrionaceae, derived from marine sponges and bryozoans, are the most promising candidates within the order Enterobacterales. Furthermore, 389 putative hydrolases from the α/β superfamily were identified in 23 analyzed genomes, of which 22 were sequenced for this study. Several candidates showed similarities with known PETases, indicating underlying enzymatic potential within the order Enterobacterales for PET degradation.
塑料已迅速成为现代生活中不可或缺的一部分。由于过度生产和不当的废物处理,它们被认为是几乎所有生境类型中存在的污染物。虽然有几种聚合物,但聚对苯二甲酸乙二醇酯(PET)由于其在环境中的丰度而受到特别关注。需要一种既具有成本效益又对生态友好的解决方案来处理这种污染物。微生物解聚酶的使用可以为塑料降解提供生物途径,尽管这些酶的全部潜力尚未被发现。本研究的目的是使用(1)基于平板的筛选方法来研究从各种有机和环境来源中收集的肠杆菌目海洋细菌的塑料降解潜力;(2)进行基因组分析以鉴定可能与PET降解相关的聚酯酶。从海洋共生研究单元(Research Unit Marine symbioses - geomar)的RD3菌株收集中获得126株细菌,并依次检测酯酶和聚酯酶活性,这里将两者结合称为pase样活性。结果表明,从海绵和苔藓虫中分离出来的Alteromonadaceae、Shewanellaceae和Vibrionaceae是肠杆菌目中最有希望的候选微生物。此外,在分析的23个基因组中鉴定出389个来自α/β超家族的推定水解酶,其中22个测序用于本研究。一些候选物显示出与已知的PET酶的相似性,表明肠杆菌目中潜在的PET降解酶潜力。
{"title":"Bioprospecting for polyesterase activity relevant for PET degradation in marine Enterobacterales isolates.","authors":"Denisse Galarza-Verkovitch, Onur Turak, Jutta Wiese, Tanja Rahn, Ute Hentschel, Erik Borchert","doi":"10.3934/microbiol.2023027","DOIUrl":"https://doi.org/10.3934/microbiol.2023027","url":null,"abstract":"<p><p>Plastics have quickly become an integral part of modern life. Due to excessive production and improper waste disposal, they are recognized as contaminants present in practically all habitat types. Although there are several polymers, polyethylene terephthalate (PET) is of particular concern due to its abundance in the environment. There is a need for a solution that is both cost-effective and ecologically friendly to address this pollutant. The use of microbial depolymerizing enzymes could offer a biological avenue for plastic degradation, though the full potential of these enzymes is yet to be uncovered. The purpose of this study was to use (1) plate-based screening methods to investigate the plastic degradation potential of marine bacteria from the order Enterobacterales collected from various organismal and environmental sources, and (2) perform genome-based analysis to identify polyesterases potentially related to PET degradation. 126 bacterial isolates were obtained from the strain collection of RD3, Research Unit Marine Symbioses-GEOMAR-and sequentially tested for esterase and polyesterase activity, in combination here referred to as PETase-like activity. The results show that members of the microbial families <i>Alteromonadaceae</i>, <i>Shewanellaceae</i>, and <i>Vibrionaceae</i>, derived from marine sponges and bryozoans, are the most promising candidates within the order Enterobacterales. Furthermore, 389 putative hydrolases from the α/β superfamily were identified in 23 analyzed genomes, of which 22 were sequenced for this study. Several candidates showed similarities with known PETases, indicating underlying enzymatic potential within the order Enterobacterales for PET degradation.</p>","PeriodicalId":46108,"journal":{"name":"AIMS Microbiology","volume":"9 3","pages":"518-539"},"PeriodicalIF":4.8,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10462454/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10184024","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-01-01DOI: 10.3934/microbiol.2023024
Ashok Chakraborty, Anil Diwan, Jayant Tatake
In recent years studies of nanomaterials have been explored in the field of microbiology due to the increasing evidence of antibiotic resistance. Nanomaterials could be inorganic or organic, and they may be synthesized from natural products from plant or animal origin. The therapeutic applications of nano-materials are wide, from diagnosis of disease to targeted delivery of drugs. Broad-spectrum antiviral and antimicrobial activities of nanoparticles are also well evident. The ratio of nanoparticles surface area to their volume is high and that allows them to be an advantageous vehicle of drugs in many respects. Effective uses of various materials for the synthesis of nanoparticles impart much specificity in them to meet the requirements of specific therapeutic strategies. The potential therapeutic use of nanoparticles and their mechanisms of action against infections from bacteria, fungi and viruses were the focus of this review. Further, their potential advantages, drawbacks, limitations and side effects are also included here. Researchers are characterizing the exposure pathways of nano-medicines that may cause serious toxicity to the subjects or the environment. Indeed, societal ethical issues in using nano-medicines pose a serious question to scientists beyond anything.
{"title":"Prospect of nanomaterials as antimicrobial and antiviral regimen.","authors":"Ashok Chakraborty, Anil Diwan, Jayant Tatake","doi":"10.3934/microbiol.2023024","DOIUrl":"https://doi.org/10.3934/microbiol.2023024","url":null,"abstract":"<p><p>In recent years studies of nanomaterials have been explored in the field of microbiology due to the increasing evidence of antibiotic resistance. Nanomaterials could be inorganic or organic, and they may be synthesized from natural products from plant or animal origin. The therapeutic applications of nano-materials are wide, from diagnosis of disease to targeted delivery of drugs. Broad-spectrum antiviral and antimicrobial activities of nanoparticles are also well evident. The ratio of nanoparticles surface area to their volume is high and that allows them to be an advantageous vehicle of drugs in many respects. Effective uses of various materials for the synthesis of nanoparticles impart much specificity in them to meet the requirements of specific therapeutic strategies. The potential therapeutic use of nanoparticles and their mechanisms of action against infections from bacteria, fungi and viruses were the focus of this review. Further, their potential advantages, drawbacks, limitations and side effects are also included here. Researchers are characterizing the exposure pathways of nano-medicines that may cause serious toxicity to the subjects or the environment. Indeed, societal ethical issues in using nano-medicines pose a serious question to scientists beyond anything.</p>","PeriodicalId":46108,"journal":{"name":"AIMS Microbiology","volume":"9 3","pages":"444-466"},"PeriodicalIF":4.8,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10462459/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10184027","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-01-01DOI: 10.3934/microbiol.2023012
Cheng Zhen, Xian-Feng Ge, Yi-Ting Lu, Wen-Zheng Liu
Surfactin, a cyclic lipopeptide produced by microbes belonging to the genus Bacillus, is one of the most effective biosurfactants available in many industrial fields. However, its low production and high cost have intensively constrained its commercial applications. In this review, we first summarize the molecular structure, biological properties, beneficial roles and potential applications of surfactin in the fields of medical care and food safety, highlighting the great medical and commercial values of making its industrial production into reality. Further, genetic regulation for surfactin biosynthesis and advanced strategies for enhancing its microbial production, including optimizing fermentation conditions, rational genetic engineering and synthetic biology combined with metabolic engineering approaches, are elucidated. Finally, prospects for improving surfactin biosynthesis are discussed, and the establishment of suitable chassis hosts for exogenous production of surfactin might serve as an important strategy in future research.
{"title":"Chemical structure, properties and potential applications of surfactin, as well as advanced strategies for improving its microbial production.","authors":"Cheng Zhen, Xian-Feng Ge, Yi-Ting Lu, Wen-Zheng Liu","doi":"10.3934/microbiol.2023012","DOIUrl":"https://doi.org/10.3934/microbiol.2023012","url":null,"abstract":"<p><p>Surfactin, a cyclic lipopeptide produced by microbes belonging to the genus <i>Bacillus</i>, is one of the most effective biosurfactants available in many industrial fields. However, its low production and high cost have intensively constrained its commercial applications. In this review, we first summarize the molecular structure, biological properties, beneficial roles and potential applications of surfactin in the fields of medical care and food safety, highlighting the great medical and commercial values of making its industrial production into reality. Further, genetic regulation for surfactin biosynthesis and advanced strategies for enhancing its microbial production, including optimizing fermentation conditions, rational genetic engineering and synthetic biology combined with metabolic engineering approaches, are elucidated. Finally, prospects for improving surfactin biosynthesis are discussed, and the establishment of suitable chassis hosts for exogenous production of surfactin might serve as an important strategy in future research.</p>","PeriodicalId":46108,"journal":{"name":"AIMS Microbiology","volume":"9 2","pages":"195-217"},"PeriodicalIF":4.8,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10113169/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9521128","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-12-22eCollection Date: 2022-01-01DOI: 10.3934/microbiol.2022035
Esther Mezhibovsky, Yue Wu, Fiona G Bawagan, Kevin M Tveter, Samantha Szeto, Diana Roopchand
A healthy gastrointestinal tract functions as a highly selective barrier, allowing the absorption of nutrients and metabolites while preventing gut bacteria and other xenobiotic compounds from entering host circulation and tissues. The intestinal epithelium and intestinal mucus provide a physical first line of defense against resident microbes, pathogens and xenotoxic compounds. Prior studies have indicated that the gut microbe Akkermansia muciniphila, a mucin-metabolizer, can stimulate intestinal mucin thickness to improve gut barrier integrity. Grape polyphenol (GP) extracts rich in B-type proanthocyanidin (PAC) compounds have been found to increase the relative abundance of A. muciniphila, suggesting that PACs alter the gut microbiota to support a healthy gut barrier. To further investigate the effect of GPs on the gut barrier and A. muciniphila, male C57BL/6 mice were fed a high-fat diet (HFD) or low-fat diet (LFD) with or without 1% GPs (HFD-GP, LFD-GP) for 12 weeks. Compared to the mice fed unsupplemented diets, GP-supplemented mice showed increased relative abundance of fecal and cecal A. muciniphila, a reduction in total bacteria, a diminished colon mucus layer and increased fecal mucus content. GP supplementation also reduced the presence of goblet cells regardless of dietary fat. Compared to the HFD group, ileal gene expression of lipopolysaccharide (LPS)-binding protein (Lbp), an acute-phase protein that promotes pro-inflammatory cytokine expression, was reduced in the HFD-GP group, suggesting reduced LPS in circulation. Despite depletion of the colonic mucus layer, markers of inflammation (Ifng, Il1b, Tnfa, and Nos2) were similar among the four groups, with the exception that ileal Il6 mRNA levels were lower in the LFD-GP group compared to the LFD group. Our findings suggest that the GP-induced increase in A. muciniphila promotes redistribution of the intestinal mucus layer to the intestinal lumen, and that the GP-induced decrease in total bacteria results in a less inflammatory intestinal milieu.
{"title":"Impact of grape polyphenols on <i>Akkermansia muciniphila</i> and the gut barrier.","authors":"Esther Mezhibovsky, Yue Wu, Fiona G Bawagan, Kevin M Tveter, Samantha Szeto, Diana Roopchand","doi":"10.3934/microbiol.2022035","DOIUrl":"10.3934/microbiol.2022035","url":null,"abstract":"<p><p>A healthy gastrointestinal tract functions as a highly selective barrier, allowing the absorption of nutrients and metabolites while preventing gut bacteria and other xenobiotic compounds from entering host circulation and tissues. The intestinal epithelium and intestinal mucus provide a physical first line of defense against resident microbes, pathogens and xenotoxic compounds. Prior studies have indicated that the gut microbe <i>Akkermansia muciniphila</i>, a mucin-metabolizer, can stimulate intestinal mucin thickness to improve gut barrier integrity. Grape polyphenol (GP) extracts rich in B-type proanthocyanidin (PAC) compounds have been found to increase the relative abundance of <i>A. muciniphila</i>, suggesting that PACs alter the gut microbiota to support a healthy gut barrier. To further investigate the effect of GPs on the gut barrier and <i>A. muciniphila</i>, male C57BL/6 mice were fed a high-fat diet (HFD) or low-fat diet (LFD) with or without 1% GPs (HFD-GP, LFD-GP) for 12 weeks. Compared to the mice fed unsupplemented diets, GP-supplemented mice showed increased relative abundance of fecal and cecal <i>A. muciniphila</i>, a reduction in total bacteria, a diminished colon mucus layer and increased fecal mucus content. GP supplementation also reduced the presence of goblet cells regardless of dietary fat. Compared to the HFD group, ileal gene expression of lipopolysaccharide (LPS)-binding protein (<i>Lbp</i>), an acute-phase protein that promotes pro-inflammatory cytokine expression, was reduced in the HFD-GP group, suggesting reduced LPS in circulation. Despite depletion of the colonic mucus layer, markers of inflammation (<i>Ifng, Il1b, Tnfa, and Nos2</i>) were similar among the four groups, with the exception that ileal <i>Il6</i> mRNA levels were lower in the LFD-GP group compared to the LFD group. Our findings suggest that the GP-induced increase in <i>A. muciniphila</i> promotes redistribution of the intestinal mucus layer to the intestinal lumen, and that the GP-induced decrease in total bacteria results in a less inflammatory intestinal milieu.</p>","PeriodicalId":46108,"journal":{"name":"AIMS Microbiology","volume":"8 4","pages":"544-565"},"PeriodicalIF":4.8,"publicationDate":"2022-12-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9834079/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10619453","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-11-16eCollection Date: 2022-01-01DOI: 10.3934/microbiol.2022029
Sirio Fiorino, Andrea Carusi, Wandong Hong, Paolo Cernuschi, Claudio Giuseppe Gallo, Emanuele Ferrara, Thais Maloberti, Michela Visani, Federico Lari, Dario de Biase, Maddalena Zippi
In recent weeks, the rate of SARS-CoV-2 infections has been progressively increasing all over the globe, even in countries where vaccination programs have been strongly implemented. In these regions in 2021, a reduction in the number of hospitalizations and deaths compared to 2020 was observed. This decrease is certainly associated with the introduction of vaccination measures. The process of the development of effective vaccines represents an important challenge. Overall, the breakthrough infections occurring in vaccinated subjects are in most cases less severe than those observed in unvaccinated individuals. This review examines the factors affecting the immunogenicity of vaccines against SARS-CoV-2 and the possible role of nutrients in modulating the response of distinct immune cells to the vaccination.
{"title":"SARS-CoV-2 vaccines: What we know, what we can do to improve them and what we could learn from other well-known viruses.","authors":"Sirio Fiorino, Andrea Carusi, Wandong Hong, Paolo Cernuschi, Claudio Giuseppe Gallo, Emanuele Ferrara, Thais Maloberti, Michela Visani, Federico Lari, Dario de Biase, Maddalena Zippi","doi":"10.3934/microbiol.2022029","DOIUrl":"10.3934/microbiol.2022029","url":null,"abstract":"<p><p>In recent weeks, the rate of SARS-CoV-2 infections has been progressively increasing all over the globe, even in countries where vaccination programs have been strongly implemented. In these regions in 2021, a reduction in the number of hospitalizations and deaths compared to 2020 was observed. This decrease is certainly associated with the introduction of vaccination measures. The process of the development of effective vaccines represents an important challenge. Overall, the breakthrough infections occurring in vaccinated subjects are in most cases less severe than those observed in unvaccinated individuals. This review examines the factors affecting the immunogenicity of vaccines against SARS-CoV-2 and the possible role of nutrients in modulating the response of distinct immune cells to the vaccination.</p>","PeriodicalId":46108,"journal":{"name":"AIMS Microbiology","volume":"8 4","pages":"422-453"},"PeriodicalIF":2.7,"publicationDate":"2022-11-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9834075/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9187685","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Concern about microbial tolerance and resistance to established antimicrobials drives research into alternatives for local antiseptic wound treatment. Precise efficacy profiles are thereby important in the evaluation of potential alternative antimicrobials, and protein interference ("protein error") is a key factor. Here, the antimicrobial efficacy of cetylpyridinium chloride (CPC) and miramistin (MST) was compared to the established antimicrobials octenidine (OCT), povidon-iodine (PVP-I), polyhexamethylene-biguanide (PHMB) and chlorhexidine (CHX). Efficacy was evaluated after 0.5, 1, 3, 5 and 10 min against Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli, Enterococcus faecium and Candida albicans using an in vitro quantitative suspension method (based on DIN EN 13727). To investigate protein interference, 0.3% or 3% bovine albumin was used as the challenge. OCT and PVP-I demonstrated a significant efficacy within 0.5 min, regardless of the microbial organism and protein challenge (p < 0.01). CPC and MST showed no inferiority in efficacy, with only MST needing up to 3 min to achieve the same microbial reduction. PHMB and CHX also achieved significant reduction rates over the tested time-course, yet demonstrated a necessity for prolonged exposure (up to 10 min) for comparable reduction. A protein interference was predominantly observed for PHMB against S. aureus, but without statistically significant differences in antimicrobial efficacy between the 0.3% and 3% protein challenges. All other tested agents showed no relevant interference with the presence of protein. CPC and MST proved to be non-inferior to established wound antiseptics agents in vitro. In fact, CPC showed a more efficient reduction than PHMB and CHX despite there being an introduced protein challenge. Both agents demonstrated no significant "protein error" under challenging conditions (3% albumin), posing them as valid potential candidates for alternative antimicrobials in wound management.
{"title":"Antimicrobials cetylpyridinium-chloride and miramistin demonstrate non-inferiority and no \"protein-error\" compared to established wound care antiseptics <i>in vitro</i>.","authors":"Julian-Dario Rembe, Vivian-Denise Thompson, Ewa Klara Stuermer","doi":"10.3934/microbiol.2022026","DOIUrl":"10.3934/microbiol.2022026","url":null,"abstract":"<p><p>Concern about microbial tolerance and resistance to established antimicrobials drives research into alternatives for local antiseptic wound treatment. Precise efficacy profiles are thereby important in the evaluation of potential alternative antimicrobials, and protein interference (\"protein error\") is a key factor. Here, the antimicrobial efficacy of cetylpyridinium chloride (CPC) and miramistin (MST) was compared to the established antimicrobials octenidine (OCT), povidon-iodine (PVP-I), polyhexamethylene-biguanide (PHMB) and chlorhexidine (CHX). Efficacy was evaluated after 0.5, 1, 3, 5 and 10 min against <i>Staphylococcus aureus</i>, <i>Pseudomonas aeruginosa, Escherichia coli</i>, <i>Enterococcus faecium</i> and <i>Candida albicans</i> using an in vitro quantitative suspension method (based on DIN EN 13727). To investigate protein interference, 0.3% or 3% bovine albumin was used as the challenge. OCT and PVP-I demonstrated a significant efficacy within 0.5 min, regardless of the microbial organism and protein challenge (<i>p</i> < 0.01). CPC and MST showed no inferiority in efficacy, with only MST needing up to 3 min to achieve the same microbial reduction. PHMB and CHX also achieved significant reduction rates over the tested time-course, yet demonstrated a necessity for prolonged exposure (up to 10 min) for comparable reduction. A protein interference was predominantly observed for PHMB against <i>S. aureus</i>, but without statistically significant differences in antimicrobial efficacy between the 0.3% and 3% protein challenges. All other tested agents showed no relevant interference with the presence of protein. CPC and MST proved to be non-inferior to established wound antiseptics agents in vitro. In fact, CPC showed a more efficient reduction than PHMB and CHX despite there being an introduced protein challenge. Both agents demonstrated no significant \"protein error\" under challenging conditions (3% albumin), posing them as valid potential candidates for alternative antimicrobials in wound management.</p>","PeriodicalId":46108,"journal":{"name":"AIMS Microbiology","volume":"8 4","pages":"372-387"},"PeriodicalIF":2.7,"publicationDate":"2022-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9834083/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10619452","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-09-16eCollection Date: 2022-01-01DOI: 10.3934/microbiol.2022025
Nurul Alia Syufina Abu Bakar, Nur Aliyyah Khuzaini, Siti Baidurah
Biomass fuel is one of the renewable energy sources that can be produced by valorization of palm oil mill effluent (POME) and empty fruit bunch (EFB). POME and EFB are available abundantly in Malaysia and only small portion is utilized to produce other value-added products. The objective of this study is to: (1) utilize the wastes from agro-industrial sector especially palm oil wastes and bio-valorize into value-added product of biomass fuel with high CEV, and simultaneously (2) reduce the waste accumulated in the palm oil factory. In this study, co-fermentation of bacteria (Lysinibacillus sp.) and fungus (Aspergillus flavus) at 37 °C, 180 rpm for 5 days, followed by overnight oven-dry at 85 °C was conducted utilizing a mixture of POME and EFB with the ratio of 7:3 at laboratory scale. Three fermentation medium conditions were performed, namely: (1) Group 1: autoclaved POME and EFB without addition of any microorganisms, (2) Group 2: autoclaved POME and EFB with the addition of Lysinibacillus sp. LC 556247 and Aspergillus flavus, and (3) Group 3: POME and EFB as it is (non-sterile). Among all condition, Group 2 with co-fermentation evinced the highest calorific energy value (CEV) of 26.71 MJ/kg, highest biochemical oxygen demand (BOD) removal efficiency of 61.11%, chemical oxygen demand (COD) removal efficiency at 48.47%, and total suspended solid (TSS) reduction of 37.12%. Overall, this study successfully utilized abundant POME and EFB waste and turn into value added product of renewable biomass fuel with high CEV percentage and simultaneously able to reduce abundant liquid waste.
{"title":"Co-fermentation involving <i>Lysinibacillus</i> sp. and <i>Aspergillus flavus</i> for simultaneous palm oil waste treatment and renewable biomass fuel production.","authors":"Nurul Alia Syufina Abu Bakar, Nur Aliyyah Khuzaini, Siti Baidurah","doi":"10.3934/microbiol.2022025","DOIUrl":"https://doi.org/10.3934/microbiol.2022025","url":null,"abstract":"<p><p>Biomass fuel is one of the renewable energy sources that can be produced by valorization of palm oil mill effluent (POME) and empty fruit bunch (EFB). POME and EFB are available abundantly in Malaysia and only small portion is utilized to produce other value-added products. The objective of this study is to: (1) utilize the wastes from agro-industrial sector especially palm oil wastes and bio-valorize into value-added product of biomass fuel with high CEV, and simultaneously (2) reduce the waste accumulated in the palm oil factory. In this study, co-fermentation of bacteria (<i>Lysinibacillus</i> sp.) and fungus (<i>Aspergillus flavus</i>) at 37 °C, 180 rpm for 5 days, followed by overnight oven-dry at 85 °C was conducted utilizing a mixture of POME and EFB with the ratio of 7:3 at laboratory scale. Three fermentation medium conditions were performed, namely: (1) Group 1: autoclaved POME and EFB without addition of any microorganisms, (2) Group 2: autoclaved POME and EFB with the addition of <i>Lysinibacillus</i> sp. LC 556247 and <i>Aspergillus flavus</i>, and (3) Group 3: POME and EFB as it is (non-sterile). Among all condition, Group 2 with co-fermentation evinced the highest calorific energy value (CEV) of 26.71 MJ/kg, highest biochemical oxygen demand (BOD) removal efficiency of 61.11%, chemical oxygen demand (COD) removal efficiency at 48.47%, and total suspended solid (TSS) reduction of 37.12%. Overall, this study successfully utilized abundant POME and EFB waste and turn into value added product of renewable biomass fuel with high CEV percentage and simultaneously able to reduce abundant liquid waste.</p>","PeriodicalId":46108,"journal":{"name":"AIMS Microbiology","volume":"8 3","pages":"357-371"},"PeriodicalIF":4.8,"publicationDate":"2022-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9576501/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"40657935","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-09-15eCollection Date: 2022-01-01DOI: 10.3934/microbiol.2022024
T Amrouche, M L Chikindas
COVID-19 pandemic is currently causing high mortality and economic crisis, and several drugs-based therapeutic strategies and vaccines are unfortunately used with little efficiency. Therefore, here is an urgent need to provide additives therapies that prevent or improve symptoms in populations infected by SARS-CoV-2 variants. This review aimed to examine relevant scientific information related to SARS-CoV-2 and host antiviral immunity, as well the possible role of probiotics in gut-lung cross talk pathways to promote lung immune response to COVID-19 infection. We searched online databases such as PubMed, Embase, Chinese databases, and selected articles and studies with relevant data reported on COVID-19 and other respiratory viral infections. Recent research highlighted potential immunomodulatory activities of probiotics assessed in animal models and clinical trials. However, the role of probiotics and gut microbiome in COVID-19 management, and approaches with significant understanding in molecular mechanism of probiotic action remain poorly investigated. Clinical investigations as well as animal model studies published have demonstrated that probiotics such as Lactobacillus rhamnosus and Bifidumbacterium lactis HN019, may influence positively not only microbiota balance but also antiviral immunity by improving both innate and adaptive responses and controlling inflammatory reaction in respiratory viral infection. Given the immunological interactions in gut-lung axis and the crucial role of probiotics in modulating immune responses by promoting dendritic cells (DCs) to regulate T cell responses, we hypothesized that application of probiotics may be successful in prevention or treatment of both intestinal disorders and airway diseases in patients with COVID-19.
{"title":"Probiotics for immunomodulation in prevention against respiratory viral infections with special emphasis on COVID-19.","authors":"T Amrouche, M L Chikindas","doi":"10.3934/microbiol.2022024","DOIUrl":"https://doi.org/10.3934/microbiol.2022024","url":null,"abstract":"<p><p>COVID-19 pandemic is currently causing high mortality and economic crisis, and several drugs-based therapeutic strategies and vaccines are unfortunately used with little efficiency. Therefore, here is an urgent need to provide additives therapies that prevent or improve symptoms in populations infected by SARS-CoV-2 variants. This review aimed to examine relevant scientific information related to SARS-CoV-2 and host antiviral immunity, as well the possible role of probiotics in gut-lung cross talk pathways to promote lung immune response to COVID-19 infection. We searched online databases such as PubMed, Embase, Chinese databases, and selected articles and studies with relevant data reported on COVID-19 and other respiratory viral infections. Recent research highlighted potential immunomodulatory activities of probiotics assessed in animal models and clinical trials. However, the role of probiotics and gut microbiome in COVID-19 management, and approaches with significant understanding in molecular mechanism of probiotic action remain poorly investigated. Clinical investigations as well as animal model studies published have demonstrated that probiotics such as <i>Lactobacillus rhamnosus</i> and <i>Bifidumbacterium lactis</i> HN019, may influence positively not only microbiota balance but also antiviral immunity by improving both innate and adaptive responses and controlling inflammatory reaction in respiratory viral infection. Given the immunological interactions in gut-lung axis and the crucial role of probiotics in modulating immune responses by promoting dendritic cells (DCs) to regulate T cell responses, we hypothesized that application of probiotics may be successful in prevention or treatment of both intestinal disorders and airway diseases in patients with COVID-19.</p>","PeriodicalId":46108,"journal":{"name":"AIMS Microbiology","volume":"8 3","pages":"338-356"},"PeriodicalIF":4.8,"publicationDate":"2022-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9576497/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"40657934","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This study was designed to investigate, at a laboratory scale, the possibility of valorizing the leftover carob fruits to produce the eco-friendly biopolymer polyhydroxybutyrate (PHB) by using the bacterial strain Bacillus paramycoides, which has been isolated from the botanical garden of Skikda University in Algeria. The PHB production was tested under various conditions: a pH of 3-8, temperature range of 30-44 °C, carob extracted molasses concentration of 2-8% v/v, an incubation time of 24-96 h and an agitation speed of 150-300 rpm. The effects of different nitrogen sources and carob extracted molasses treatment types were also investigated. The PHB concentration was determined quantitatively as crotonic acid by measuring the absorbance at 300 nm. Cell growth was quantified by measuring the density of the culture at 600 nm. The presence of PHB was confirmed by applying high-performance liquid chromatography (HPLC) using an Aminex HPX-87H and implementing gas chromatography analysis. The best yield of PHB synthesis was obtained by using 6% v/v of 5 M H2SO4 treated with carob molasses as a carbon source, with peptone as a nitrogen source; incubation was conducted at 37 °C for 96 h at an agitation speed of 300 rpm (114.95 mg/L). The HPLC analysis confirmed the synthesis of PHB by B. paramycoides to have a chromatogram retention time of 22.5 min. Carob waste was successfully valorized to PHB.
{"title":"Potential use of <i>Bacillus paramycoides</i> for the production of the biopolymer polyhydroxybutyrate from leftover carob fruit agro-waste.","authors":"Leila Djerrab, Zohra Chekroud, Amer Rouabhia, Mohamed Abdesselem Dems, Imane Attailia, Luis Isidoro Romero Garcia, Mustapha Adnane Smadi","doi":"10.3934/microbiol.2022023","DOIUrl":"https://doi.org/10.3934/microbiol.2022023","url":null,"abstract":"<p><p>This study was designed to investigate, at a laboratory scale, the possibility of valorizing the leftover carob fruits to produce the eco-friendly biopolymer polyhydroxybutyrate (PHB) by using the bacterial strain <i>Bacillus paramycoides</i>, which has been isolated from the botanical garden of Skikda University in Algeria. The PHB production was tested under various conditions: a pH of 3-8, temperature range of 30-44 °C, carob extracted molasses concentration of 2-8% v/v, an incubation time of 24-96 h and an agitation speed of 150-300 rpm. The effects of different nitrogen sources and carob extracted molasses treatment types were also investigated. The PHB concentration was determined quantitatively as crotonic acid by measuring the absorbance at 300 nm. Cell growth was quantified by measuring the density of the culture at 600 nm. The presence of PHB was confirmed by applying high-performance liquid chromatography (HPLC) using an Aminex HPX-87H and implementing gas chromatography analysis. The best yield of PHB synthesis was obtained by using 6% v/v of 5 M H<sub>2</sub>SO<sub>4</sub> treated with carob molasses as a carbon source, with peptone as a nitrogen source; incubation was conducted at 37 °C for 96 h at an agitation speed of 300 rpm (114.95 mg/L). The HPLC analysis confirmed the synthesis of PHB by <i>B. paramycoides</i> to have a chromatogram retention time of 22.5 min. Carob waste was successfully valorized to PHB.</p>","PeriodicalId":46108,"journal":{"name":"AIMS Microbiology","volume":"8 3","pages":"318-337"},"PeriodicalIF":4.8,"publicationDate":"2022-08-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9576499/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"40657937","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-07-15eCollection Date: 2022-01-01DOI: 10.3934/microbiol.2022022
Susan Nadin-Davis, Louise Pope, John Devenish, Ray Allain, Dele Ogunremi
Salmonella enterica subsp. enterica serovar Enteritidis remains one of the most important foodborne pathogens worldwide. To minimise its public health impact when outbreaks of the disease occur, timely investigation to identify and recall the contaminated food source is necessary. Central to this approach is the need for rapid and accurate identification of the bacterial subtype epidemiologically linked to the outbreak. While traditional methods of S. Enteritidis subtyping, such as pulsed field gel electrophoresis (PFGE) and phage typing (PT), have played an important role, the clonal nature of this organism has spurred efforts to improve subtyping resolution and timeliness through molecular based approaches. This study uses a cohort of 92 samples, recovered from a variety of sources, to compare these two traditional methods for S. Enteritidis subtyping with recently developed molecular techniques. These latter methods include the characterisation of two clustered regularly interspaced short palindromic repeats (CRISPR) loci, either in isolation or together with sequence analysis of virulence genes such as fimH. For comparison, another molecular technique developed in this laboratory involved the scoring of 60 informative single nucleotide polymorphisms (SNPs) distributed throughout the genome. Based on both the number of subtypes identified and Simpson's index of diversity, the CRISPR method was the least discriminatory and not significantly improved with the inclusion of fimH gene sequencing. While PT analysis identified the most subtypes, the SNP-PCR process generated the greatest index of diversity value. Combining methods consistently improved the number of subtypes identified, with the SNP/CRISPR typing scheme generating a level of diversity comparable with that of PT/PFGE. While these molecular methods, when combined, may have significant utility in real-world situations, this study suggests that CRISPR analysis alone lacks the discriminatory capability required to support investigations of foodborne disease outbreaks.
{"title":"Evaluation of the use of CRISPR loci for discrimination of <i>Salmonella enterica</i> subsp. <i>enterica</i> serovar Enteritidis strains recovered in Canada and comparison with other subtyping methods.","authors":"Susan Nadin-Davis, Louise Pope, John Devenish, Ray Allain, Dele Ogunremi","doi":"10.3934/microbiol.2022022","DOIUrl":"10.3934/microbiol.2022022","url":null,"abstract":"<p><p><i>Salmonella enterica</i> subsp. <i>enterica</i> serovar Enteritidis remains one of the most important foodborne pathogens worldwide. To minimise its public health impact when outbreaks of the disease occur, timely investigation to identify and recall the contaminated food source is necessary. Central to this approach is the need for rapid and accurate identification of the bacterial subtype epidemiologically linked to the outbreak. While traditional methods of <i>S</i>. Enteritidis subtyping, such as pulsed field gel electrophoresis (PFGE) and phage typing (PT), have played an important role, the clonal nature of this organism has spurred efforts to improve subtyping resolution and timeliness through molecular based approaches. This study uses a cohort of 92 samples, recovered from a variety of sources, to compare these two traditional methods for <i>S</i>. Enteritidis subtyping with recently developed molecular techniques. These latter methods include the characterisation of two clustered regularly interspaced short palindromic repeats (CRISPR) loci, either in isolation or together with sequence analysis of virulence genes such as <i>fim</i>H. For comparison, another molecular technique developed in this laboratory involved the scoring of 60 informative single nucleotide polymorphisms (SNPs) distributed throughout the genome. Based on both the number of subtypes identified and Simpson's index of diversity, the CRISPR method was the least discriminatory and not significantly improved with the inclusion of <i>fim</i>H gene sequencing. While PT analysis identified the most subtypes, the SNP-PCR process generated the greatest index of diversity value. Combining methods consistently improved the number of subtypes identified, with the SNP/CRISPR typing scheme generating a level of diversity comparable with that of PT/PFGE. While these molecular methods, when combined, may have significant utility in real-world situations, this study suggests that CRISPR analysis alone lacks the discriminatory capability required to support investigations of foodborne disease outbreaks.</p>","PeriodicalId":46108,"journal":{"name":"AIMS Microbiology","volume":"8 3","pages":"300-317"},"PeriodicalIF":2.7,"publicationDate":"2022-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9576496/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"40657933","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}