Pub Date : 2026-05-18DOI: 10.1186/s13213-026-01857-7
Nady Khairy Elbarbary, Neveen M. Abdelmotilib, Marwa O. Abd El-Halim, Doaa A. Abdallah, Yehia Hazzazi, Mari Sumayli, Ramadan Taha, Latifa Al Husnain, Muneera D. F. Alkahtani, Ahmed Ezzat Ahmed, Sohaila F. El-Hawary, Marwa M. Abdallah, Basma Gamal
Abstract Objectives This study aimed to characterize drug-resistant Streptococcus spp. isolated from food and human sources in Upper Egypt, focusing on their virulence and antimicrobial resistance profiles, and to evaluate the in vitro antibacterial activity of an oregano essential oil nanoemulsion. Materials and methods A total of 440 food and human samples were collected in Aswan, Upper Egypt, and screened using conventional microbiological methods. Molecular confirmation was performed by detecting the tuf gene, followed by species identification using the 16 S rRNA and spn9802 genes. Selected virulence ( scpB , Rib , Lmb , and cylE ) and resistance ( aac6-aph2 , pbp1A , and tetO ) genes were detected by PCR. Antimicrobial susceptibility testing and the multiple antibiotic resistance (MAR) index were determined. The antibacterial activity of the oregano nanoemulsion was assessed using inhibition zone assays at varying concentrations. Results Streptococcus spp. were detected in 22% of samples, with higher prevalence in throat swabs (34%) and raw milk (21.9%). Predominant species included S. agalactiae , S. pyogenes , S. dysgalactiae , S. pneumoniae , and S. uberis . Virulence genes were variably distributed, with scpB (33%) and cylE (31.8%) most frequent. Resistance genes were moderately detected, particularly tetO (21.2%). Most isolates were resistant to β-lactams but fully susceptible to ceftaroline and fosfomycin; the mean MAR index was 0.477. The oregano nanoemulsion showed concentration-dependent antibacterial activity. Conclusion Drug-resistant Streptococcus spp. from food and human sources in Upper Egypt carry important virulence and resistance determinants. The oregano essential oil nanoemulsion demonstrated promising in vitro antibacterial activity, suggesting potential as a natural antimicrobial; however, further in vivo and safety studies are required.
{"title":"Characterization of drug-resistant Streptococcus spp. from food and human sources and in vitro antibacterial assessment of an oregano nanoemulsion","authors":"Nady Khairy Elbarbary, Neveen M. Abdelmotilib, Marwa O. Abd El-Halim, Doaa A. Abdallah, Yehia Hazzazi, Mari Sumayli, Ramadan Taha, Latifa Al Husnain, Muneera D. F. Alkahtani, Ahmed Ezzat Ahmed, Sohaila F. El-Hawary, Marwa M. Abdallah, Basma Gamal","doi":"10.1186/s13213-026-01857-7","DOIUrl":"https://doi.org/10.1186/s13213-026-01857-7","url":null,"abstract":"Abstract Objectives This study aimed to characterize drug-resistant Streptococcus spp. isolated from food and human sources in Upper Egypt, focusing on their virulence and antimicrobial resistance profiles, and to evaluate the in vitro antibacterial activity of an oregano essential oil nanoemulsion. Materials and methods A total of 440 food and human samples were collected in Aswan, Upper Egypt, and screened using conventional microbiological methods. Molecular confirmation was performed by detecting the tuf gene, followed by species identification using the 16 S rRNA and spn9802 genes. Selected virulence ( scpB , Rib , Lmb , and cylE ) and resistance ( aac6-aph2 , pbp1A , and tetO ) genes were detected by PCR. Antimicrobial susceptibility testing and the multiple antibiotic resistance (MAR) index were determined. The antibacterial activity of the oregano nanoemulsion was assessed using inhibition zone assays at varying concentrations. Results Streptococcus spp. were detected in 22% of samples, with higher prevalence in throat swabs (34%) and raw milk (21.9%). Predominant species included S. agalactiae , S. pyogenes , S. dysgalactiae , S. pneumoniae , and S. uberis . Virulence genes were variably distributed, with scpB (33%) and cylE (31.8%) most frequent. Resistance genes were moderately detected, particularly tetO (21.2%). Most isolates were resistant to β-lactams but fully susceptible to ceftaroline and fosfomycin; the mean MAR index was 0.477. The oregano nanoemulsion showed concentration-dependent antibacterial activity. Conclusion Drug-resistant Streptococcus spp. from food and human sources in Upper Egypt carry important virulence and resistance determinants. The oregano essential oil nanoemulsion demonstrated promising in vitro antibacterial activity, suggesting potential as a natural antimicrobial; however, further in vivo and safety studies are required.","PeriodicalId":8069,"journal":{"name":"Annals of Microbiology","volume":"76 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2026-05-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148305699","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-01-07DOI: 10.1186/s13213-025-01823-9
H. L. Li, Xian Tao, Hongji Zhang, Yafei Zhang, Qiancheng Liang, Qing Liu, Lan Luo, Yan Wang, Juan Yang, Xiaosheng Yang, Mei Fang Peng, Liangqun LI
The aim of this study was to isolate and identify a nicotine-degrading Paenarthrobacter nicotinovorans strain from the Epimedium rhizosphere, characterize its secondary metabolites, and evaluate its potential antioxidant activity against premature ovarian failure (POF). By exploring the bioactive properties of this rhizosphere microorganism, the research sought to uncover new insights into the functional roles of plant-associated microbes and discover potential natural agents for treating oxidative stress-related diseases. A strain designated YYH-1 was isolated from the E. rhizosphere and identified through morphological observations and 16S rRNA gene sequencing. Ultra-performance liquid chromatography-high resolution mass spectrometry (UPLC-HRMS) combined with GNPS molecular networking was employed to profile the chemical components of the ethyl acetate extract from YYH-1 fermentation broth. In vitro experiments utilized the human ovarian granulosa cell line (KGN) to assess the extract’s effect on D-galactose-induced cellular senescence, measuring the activity of superoxide dismutase (SOD) as an indicator of antioxidant capacity. Additionally, molecular docking was performed to elucidate the interaction mechanisms between key compounds and the Nrf2 signaling pathway. The isolate was confirmed as P. nicotinovorans YYH-1. Chemical profiling identified 21 secondary metabolites, including flavonoids, phenylpropanoids, alkaloids, fatty acids, and amino acid derivatives. In vitro studies demonstrated that the YYH-1 extract significantly mitigated D-galactose-induced cellular senescence in KGN cells and effectively upregulated superoxide dismutase (SOD) activity, which increased by 50.94%, 48.27%, and 38.01% respectively compared with that in the Model group.. Molecular docking analysis revealed that 8-prenylnaringenin, a major compound in the extract, could activate the Nrf2 signaling pathway by stably binding to Keap1 and Nrf2 receptors. This study represents the first report of P. nicotinovorans in the E. rhizosphere. The strain exhibits the potential to produce diverse bioactive secondary metabolites, and its extract demonstrates antioxidant activity against POF through the activation of the Nrf2 pathway. These findings expand our understanding of rhizosphere microbial functions and provide a basis for the development of natural anti-aging therapies targeting oxidative stress-related disorders.
{"title":"Phytochemical characterization of Paenarthrobacter nicotinovorans YYH-1 from Epimedium rhizosphere and its antioxidant-mediated in vitro activity against premature ovarian failure","authors":"H. L. Li, Xian Tao, Hongji Zhang, Yafei Zhang, Qiancheng Liang, Qing Liu, Lan Luo, Yan Wang, Juan Yang, Xiaosheng Yang, Mei Fang Peng, Liangqun LI","doi":"10.1186/s13213-025-01823-9","DOIUrl":"https://doi.org/10.1186/s13213-025-01823-9","url":null,"abstract":"The aim of this study was to isolate and identify a nicotine-degrading Paenarthrobacter nicotinovorans strain from the Epimedium rhizosphere, characterize its secondary metabolites, and evaluate its potential antioxidant activity against premature ovarian failure (POF). By exploring the bioactive properties of this rhizosphere microorganism, the research sought to uncover new insights into the functional roles of plant-associated microbes and discover potential natural agents for treating oxidative stress-related diseases. A strain designated YYH-1 was isolated from the E. rhizosphere and identified through morphological observations and 16S rRNA gene sequencing. Ultra-performance liquid chromatography-high resolution mass spectrometry (UPLC-HRMS) combined with GNPS molecular networking was employed to profile the chemical components of the ethyl acetate extract from YYH-1 fermentation broth. In vitro experiments utilized the human ovarian granulosa cell line (KGN) to assess the extract’s effect on D-galactose-induced cellular senescence, measuring the activity of superoxide dismutase (SOD) as an indicator of antioxidant capacity. Additionally, molecular docking was performed to elucidate the interaction mechanisms between key compounds and the Nrf2 signaling pathway. The isolate was confirmed as P. nicotinovorans YYH-1. Chemical profiling identified 21 secondary metabolites, including flavonoids, phenylpropanoids, alkaloids, fatty acids, and amino acid derivatives. In vitro studies demonstrated that the YYH-1 extract significantly mitigated D-galactose-induced cellular senescence in KGN cells and effectively upregulated superoxide dismutase (SOD) activity, which increased by 50.94%, 48.27%, and 38.01% respectively compared with that in the Model group.. Molecular docking analysis revealed that 8-prenylnaringenin, a major compound in the extract, could activate the Nrf2 signaling pathway by stably binding to Keap1 and Nrf2 receptors. This study represents the first report of P. nicotinovorans in the E. rhizosphere. The strain exhibits the potential to produce diverse bioactive secondary metabolites, and its extract demonstrates antioxidant activity against POF through the activation of the Nrf2 pathway. These findings expand our understanding of rhizosphere microbial functions and provide a basis for the development of natural anti-aging therapies targeting oxidative stress-related disorders.","PeriodicalId":8069,"journal":{"name":"Annals of Microbiology","volume":"76 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2026-01-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147914190","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Purpose: Fresh vegetables are essential human dietary components but are increasingly implicated in foodborne infections caused by Escherichia coli. Contamination may occur during cultivation, irrigation, handling, and retail display, and the presence of pathogenic or antimicrobial-resistant E. coli poses significant public health risks. Despite widespread vegetable consumption in Ogun State, Nigeria, limited data exist on the resistance and virulence characteristics of E. coli in these foods. This study therefore assessed antimicrobial resistance profiles and virulence genes in E. coli isolated from tomatoes, carrots, and cucumbers sold across three senatorial districts of Ogun State.
Method: A cross-sectional survey was conducted between March and October 2023, yielding 509 vegetable samples collected aseptically during three visits. Samples were enriched, cultured on MacConkey agar, and identified using standard microbiological methods. Thereafter, antimicrobial susceptibility testing was performed using the Kirby-Bauer disc diffusion method. Genomic DNA was extracted from the microbe, followed by Polymerase Chain Reaction (PCR) to detect key virulence (stx1, stx2, eae) and resistance (blaSHV, blaTEM, blaCTX, NDM, IMP, KPC, OXA-48) genes.
Results: Of the 509 vegetables analysed, 73 (14.4%) tested positive for E. coli: 34 (14.4%) from tomatoes, 27 (24.1%) from carrots, and 12 (7.5%) from cucumbers. Carrots from Ogun Central had an E. coli contamination rate of 9.8% (11/112), while cucumbers from Ogun East had a contamination rate of 1.3% (2/160). Among 34 E. coli isolates confirmed and recovered from the vegetables, 12 originated from Ogun Central, 9 from Ogun East, and 13 from Ogun West. Isolates showed resistance to all antibiotics except gentamicin and levofloxacin. Virulence genes stx1 and stx2 were detected in 3 and 2 isolates, respectively. Also, 47% of isolates carried resistance genes, and 15% carried virulence genes.
Conclusion: Fresh vegetables across the three senatorial districts of Ogun State were contaminated with E. coli, with 15% of isolates carrying virulence genes and 47% carrying antimicrobial resistance genes. The low detection of virulence genes indicates relatively low pathogenic potential, as higher levels typically signal greater infection risk. However, the presence of both virulence and resistance genes still highlights important public health concerns. These findings emphasize the need for improved farming hygiene, stricter antimicrobial regulation, and stronger surveillance.
{"title":"Assessment of resistance profiles and virulence genes in <i>Escherichia coli</i> from fresh vegetables: implications for food safety and consumer health in Ogun State, Nigeria.","authors":"Itohan Ebunoluwa Abatan, Lenis Saweda O Liverpool-Tasie, Taofik Akinyemi Shittu, Adebukunola Mobolaji Omemu, Muinah Adenike Fowora, Oluwakemi Abosede Ojo, Oluwasola Abayomi Adelusi, Adewale Olusegun Obadina","doi":"10.1186/s13213-026-01864-8","DOIUrl":"10.1186/s13213-026-01864-8","url":null,"abstract":"<p><strong>Purpose: </strong>Fresh vegetables are essential human dietary components but are increasingly implicated in foodborne infections caused by <i>Escherichia coli</i>. Contamination may occur during cultivation, irrigation, handling, and retail display, and the presence of pathogenic or antimicrobial-resistant <i>E. coli</i> poses significant public health risks. Despite widespread vegetable consumption in Ogun State, Nigeria, limited data exist on the resistance and virulence characteristics of <i>E. coli</i> in these foods. This study therefore assessed antimicrobial resistance profiles and virulence genes in <i>E. coli</i> isolated from tomatoes, carrots, and cucumbers sold across three senatorial districts of Ogun State.</p><p><strong>Method: </strong>A cross-sectional survey was conducted between March and October 2023, yielding 509 vegetable samples collected aseptically during three visits. Samples were enriched, cultured on MacConkey agar, and identified using standard microbiological methods. Thereafter, antimicrobial susceptibility testing was performed using the Kirby-Bauer disc diffusion method. Genomic DNA was extracted from the microbe, followed by Polymerase Chain Reaction (PCR) to detect key virulence (<i>stx1, stx2, eae</i>) and resistance (<i>blaSHV, blaTEM, blaCTX, NDM, IMP, KPC, OXA-48</i>) genes.</p><p><strong>Results: </strong>Of the 509 vegetables analysed, 73 (14.4%) tested positive for <i>E. coli</i>: 34 (14.4%) from tomatoes, 27 (24.1%) from carrots, and 12 (7.5%) from cucumbers. Carrots from Ogun Central had an <i>E. coli</i> contamination rate of 9.8% (11/112), while cucumbers from Ogun East had a contamination rate of 1.3% (2/160). Among 34 <i>E. coli</i> isolates confirmed and recovered from the vegetables, 12 originated from Ogun Central, 9 from Ogun East, and 13 from Ogun West. Isolates showed resistance to all antibiotics except gentamicin and levofloxacin. Virulence genes <i>stx1</i> and <i>stx2</i> were detected in 3 and 2 isolates, respectively. Also, 47% of isolates carried resistance genes, and 15% carried virulence genes.</p><p><strong>Conclusion: </strong>Fresh vegetables across the three senatorial districts of Ogun State were contaminated with <i>E. coli</i>, with 15% of isolates carrying virulence genes and 47% carrying antimicrobial resistance genes. The low detection of virulence genes indicates relatively low pathogenic potential, as higher levels typically signal greater infection risk. However, the presence of both virulence and resistance genes still highlights important public health concerns. These findings emphasize the need for improved farming hygiene, stricter antimicrobial regulation, and stronger surveillance.</p>","PeriodicalId":8069,"journal":{"name":"Annals of Microbiology","volume":"76 1","pages":"38"},"PeriodicalIF":5.1,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13617671/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149073174","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract Background Fermented glutinous rice has low alcohol content and abundant nutrients, but it is easily contaminated by Bacillus cereus during production and preservation. This study aimed to inhibit the spoilage bacterium Bacillus cereus in the fermented glutinous rice by bacteriocin-producing lactic acid bacteria and its bacteriocin. Results Bacteriocin-producing Pediococcus pentosaceus JQ2-1 was isolated from traditional sweet wine koji and its bacteriocin ZJQ2-1 was purified by ethyl acetate extraction, cation exchange chromatography, gel chromatography and reversed-phase high-performance liquid chromatography (RP-HPLC). Bacteriocin ZJQ2-1 was identified by HPLC–MS/MS, and the results showed it had a molecular weight of 1204.43 Da and the amino acid sequence was KIGLFGGAGVGKT. Further characterization analysis showed that the bacteriocin ZJQ2-1 was thermostable (30 min, 121°C), highly pH stable (2–10), sensitive to protease and exhibited broad-spectrum antibacterial ability against Gram-positive and Gram-negative bacteria. The count of Bacillus cereus in the fermented glutinous rice that was inoculated with P. pentosaceus JQ2-1 and bacteriocin ZJQ2-1 decreased by about 80% and 64% of that in the initial stage, respectively. Conclusions These results indicated the potential of P. pentosaceus JQ2-1 and bacteriocin ZJQ2-1 as a bio-preservative in glutinous rice products.
{"title":"Bacteriocin ZJQ2-1 produced by Pediococcus pentosaceus from traditional sweet wine koji: purification, characterization, and application in fermented glutinous rice","authors":"Huojian Zheng, Yongqi Yang, Cancan Qi, Qiuxiang Cheng, Qin Wang, Liping Wang","doi":"10.1186/s13213-025-01810-0","DOIUrl":"https://doi.org/10.1186/s13213-025-01810-0","url":null,"abstract":"Abstract Background Fermented glutinous rice has low alcohol content and abundant nutrients, but it is easily contaminated by Bacillus cereus during production and preservation. This study aimed to inhibit the spoilage bacterium Bacillus cereus in the fermented glutinous rice by bacteriocin-producing lactic acid bacteria and its bacteriocin. Results Bacteriocin-producing Pediococcus pentosaceus JQ2-1 was isolated from traditional sweet wine koji and its bacteriocin ZJQ2-1 was purified by ethyl acetate extraction, cation exchange chromatography, gel chromatography and reversed-phase high-performance liquid chromatography (RP-HPLC). Bacteriocin ZJQ2-1 was identified by HPLC–MS/MS, and the results showed it had a molecular weight of 1204.43 Da and the amino acid sequence was KIGLFGGAGVGKT. Further characterization analysis showed that the bacteriocin ZJQ2-1 was thermostable (30 min, 121°C), highly pH stable (2–10), sensitive to protease and exhibited broad-spectrum antibacterial ability against Gram-positive and Gram-negative bacteria. The count of Bacillus cereus in the fermented glutinous rice that was inoculated with P. pentosaceus JQ2-1 and bacteriocin ZJQ2-1 decreased by about 80% and 64% of that in the initial stage, respectively. Conclusions These results indicated the potential of P. pentosaceus JQ2-1 and bacteriocin ZJQ2-1 as a bio-preservative in glutinous rice products.","PeriodicalId":8069,"journal":{"name":"Annals of Microbiology","volume":"75 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-07-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://annalsmicrobiology.biomedcentral.com/counter/pdf/10.1186/s13213-025-01810-0","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147332371","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-09-16DOI: 10.1186/s13213-024-01763-w
Daniel Asfaw Kitessa
Fermentation is the oldest biotechnology in which a metabolic process carried out without the involvement of oxygen. It is one of the food processing methods that improve the nutrient contents and sensorial properties with potentially reducing or eliminating pathogenic microorganisms and natural toxins. The aim of this review is to compare, contrast and summarize the scientific data on the effect of fermentation on physicochemical properties, anti-nutritional factors and sensory properties of cereal-based fermented foods and beverages. The results of this review showed that fermentation improves the nutritional value of some proximate composition such as crude protein and fat contents, while decreases the carbohydrate and crude fiber contents. It also improves the bioavailability, antioxidant activities and sensory properties of cereal-based foods and beverages. This review concluded that fermentation improves the nutritional quality of proximate composition, bioavailability of minerals and phytochemicals, and decrease the anti-nutritional factors of cereal-based fermented foods and beverages.
{"title":"Review on effect of fermentation on physicochemical properties, anti-nutritional factors and sensory properties of cereal-based fermented foods and beverages","authors":"Daniel Asfaw Kitessa","doi":"10.1186/s13213-024-01763-w","DOIUrl":"https://doi.org/10.1186/s13213-024-01763-w","url":null,"abstract":"Fermentation is the oldest biotechnology in which a metabolic process carried out without the involvement of oxygen. It is one of the food processing methods that improve the nutrient contents and sensorial properties with potentially reducing or eliminating pathogenic microorganisms and natural toxins. The aim of this review is to compare, contrast and summarize the scientific data on the effect of fermentation on physicochemical properties, anti-nutritional factors and sensory properties of cereal-based fermented foods and beverages. The results of this review showed that fermentation improves the nutritional value of some proximate composition such as crude protein and fat contents, while decreases the carbohydrate and crude fiber contents. It also improves the bioavailability, antioxidant activities and sensory properties of cereal-based foods and beverages. This review concluded that fermentation improves the nutritional quality of proximate composition, bioavailability of minerals and phytochemicals, and decrease the anti-nutritional factors of cereal-based fermented foods and beverages.","PeriodicalId":8069,"journal":{"name":"Annals of Microbiology","volume":"18 1","pages":""},"PeriodicalIF":3.0,"publicationDate":"2024-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142261245","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The incidence of foodborne pathogens in ready- to-eat (RTE) can be attributed to various foodborne diseases. Most of the isolated microorganisms from RTE foods are resistant to common antibiotics and thus, resulted to treatment failure when commercially available antibiotics are administered. However, the secondary metabolites secreted by microorganisms can serve as alternative therapy that are reliable and safe. Secondary metabolites obtained from mono- and co-culture microorganisms can inhibit the growth of antibiotic-resistant microorganisms. Bioactive compounds in the secreted metabolites can be identified and utilized as sources of new antibiotics. In this study, antimicrobial activity of secondary metabolites from Lactobacillus fermentum, Saccharomyces cerevisiae, Pleurotus ostreatus, and their co-cultures were tested against foodborne pathogens isolated from RTE foods using agar well diffusion. The bioactive compounds in the metabolites were identified using gas chromatography-mass spectrometry. From a total of 100 RTE foods examined, Salmonella enterica, Shigella dysenteriae, Escherichia coli, Klebsiella pneumoniae (subsp ozaenae), Pseudomonas fluorescens, Clostridium perfringes, Bacillus cereus, Listeria monocytogens, and Staphylococcus aureus, Penicillium chrysogenum, Aspergillus flavus, and Aspergillus niger were isolated and displayed multiple antibiotic resistance. The secondary metabolites secreted by co-culture of L. fermentum + P. ostreatus + S. cerevisiae, and co-culture of P. ostreatus + S. cerevisiae have the highest (P ≤ 0.05) zones of inhibition (23.70 mm) and (21.10 mm) against E. coli, respectively. Metabolites from mono-cultured L. fermentum, P. ostreatus, and S. cerevisiae showed zones of inhibition against indicator microorganisms with values ranging from 8.80 to 11.70 mm, 9.00 to 14.30 mm, and 9.30 to 13.00 mm, respectively. Some of the bioactive compounds found in the metabolites of co-cultured microorganisms were alpha-linolenic acid (25.71%), acetic acid 3-methylbutyl ester (13.83%), trans-squalene (12.39%), pentadecylic acid (11.68%), 3- phenyllactic acid (30.13%), linolelaidic acid methyl ester (15.63%), and 4-O-methylmannose (53.74%). RTE foods contain multiple antibiotics resistance pathogens. The pronounced antimicrobial activity of the secondary metabolites against microorganisms from RTE foods could be attributed to the presence of bioactive compounds in the metabolites. These metabolites can be exploited as alternative food preservatives, biopharmaceuticals and can be used towards better health delivering systems.
即食食品中的食源性病原体可导致各种食源性疾病。从即食食品中分离出的大多数微生物对普通抗生素具有抗药性，因此，使用市售抗生素治疗时会导致治疗失败。然而，微生物分泌的次级代谢物可作为可靠、安全的替代疗法。从单培养和共培养微生物中获得的次生代谢物可以抑制抗生素耐药微生物的生长。分泌代谢物中的生物活性化合物可被鉴定并用作新抗生素的来源。本研究采用琼脂井扩散法测试了发酵乳杆菌、酿酒酵母、牡蛎及其共培养物的次生代谢物对从即食食品中分离出的食源性致病菌的抗菌活性。代谢物中的生物活性化合物采用气相色谱-质谱法进行鉴定。在检测的 100 种即食性食品中，分离出了肠炎沙门氏菌、痢疾志贺氏菌、大肠埃希氏菌、肺炎克雷伯菌（大肠杆菌亚种）、荧光假单胞菌、产气荚膜梭菌、蜡样芽孢杆菌、单核细胞李斯特菌、金黄色葡萄球菌、金黄色青霉、黄曲霉和黑曲霉，并显示出多种抗生素耐药性。L. fermentum + P. ostreatus + S. cerevisiae 共培养物和 P. ostreatus + S. cerevisiae 共培养物分泌的次生代谢物对大肠杆菌的抑菌作用分别为（23.70 毫米）和（21.10 毫米），抑菌面积最大（P ≤ 0.05）。单培养 L. fermentum、P. ostreatus 和 S. cerevisiae 的代谢物对指示微生物的抑制区分别为 8.80 至 11.70 毫米、9.00 至 14.30 毫米和 9.30 至 13.00 毫米。在共培养微生物的代谢产物中发现的一些生物活性化合物有：α-亚麻酸（25.71%）、乙酸 3-甲基丁酯（13.83%）、反式角鲨烯（12.39%）、十五烷酸（11.68%）、3-苯基乳酸（30.13%）、亚油酸甲酯（15.63%）和 4-O-甲基甘露糖（53.74%）。即食食品中含有多种抗生素耐药性病原体。次生代谢物对来自即食食品的微生物具有明显的抗菌活性，这可能是因为代谢物中含有生物活性化合物。这些代谢物可用作替代食品防腐剂和生物制药，并可用于改善健康服务系统。
{"title":"Antimicrobial metabolites from Probiotics, Pleurotus ostreatus and their co-cultures against foodborne pathogens isolated from ready-to-eat foods","authors":"Oluwaferanmi Esther Bamisi, Clement Olusola Ogidi, Bamidele Juliet Akinyele","doi":"10.1186/s13213-024-01776-5","DOIUrl":"https://doi.org/10.1186/s13213-024-01776-5","url":null,"abstract":"The incidence of foodborne pathogens in ready- to-eat (RTE) can be attributed to various foodborne diseases. Most of the isolated microorganisms from RTE foods are resistant to common antibiotics and thus, resulted to treatment failure when commercially available antibiotics are administered. However, the secondary metabolites secreted by microorganisms can serve as alternative therapy that are reliable and safe. Secondary metabolites obtained from mono- and co-culture microorganisms can inhibit the growth of antibiotic-resistant microorganisms. Bioactive compounds in the secreted metabolites can be identified and utilized as sources of new antibiotics. In this study, antimicrobial activity of secondary metabolites from Lactobacillus fermentum, Saccharomyces cerevisiae, Pleurotus ostreatus, and their co-cultures were tested against foodborne pathogens isolated from RTE foods using agar well diffusion. The bioactive compounds in the metabolites were identified using gas chromatography-mass spectrometry. From a total of 100 RTE foods examined, Salmonella enterica, Shigella dysenteriae, Escherichia coli, Klebsiella pneumoniae (subsp ozaenae), Pseudomonas fluorescens, Clostridium perfringes, Bacillus cereus, Listeria monocytogens, and Staphylococcus aureus, Penicillium chrysogenum, Aspergillus flavus, and Aspergillus niger were isolated and displayed multiple antibiotic resistance. The secondary metabolites secreted by co-culture of L. fermentum + P. ostreatus + S. cerevisiae, and co-culture of P. ostreatus + S. cerevisiae have the highest (P ≤ 0.05) zones of inhibition (23.70 mm) and (21.10 mm) against E. coli, respectively. Metabolites from mono-cultured L. fermentum, P. ostreatus, and S. cerevisiae showed zones of inhibition against indicator microorganisms with values ranging from 8.80 to 11.70 mm, 9.00 to 14.30 mm, and 9.30 to 13.00 mm, respectively. Some of the bioactive compounds found in the metabolites of co-cultured microorganisms were alpha-linolenic acid (25.71%), acetic acid 3-methylbutyl ester (13.83%), trans-squalene (12.39%), pentadecylic acid (11.68%), 3- phenyllactic acid (30.13%), linolelaidic acid methyl ester (15.63%), and 4-O-methylmannose (53.74%). RTE foods contain multiple antibiotics resistance pathogens. The pronounced antimicrobial activity of the secondary metabolites against microorganisms from RTE foods could be attributed to the presence of bioactive compounds in the metabolites. These metabolites can be exploited as alternative food preservatives, biopharmaceuticals and can be used towards better health delivering systems.","PeriodicalId":8069,"journal":{"name":"Annals of Microbiology","volume":"67 1","pages":""},"PeriodicalIF":3.0,"publicationDate":"2024-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142221084","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-08-20DOI: 10.1186/s13213-024-01774-7
Aida M. Farag, Hasnaa E-B. Ghonam, Aliaa M. El-Borai
Several antibiotics are partially metabolized by patients after administration and end up in municipal sewage systems. The fate of biodegradation in aquatic environments and the role of biodegradation in the development of bacterial resistance are poorly understood. Thus, as a crucial step in an environmental risk assessment, the biodegradability of many therapeutically significant antibiotics was investigated. A marine halophilic bacteria that degrades penicillin G (PEN-G) was isolated and identified based on morphology, physio-biochemical characteristics, and 16S rDNA sequences as Bacillus pseudomycoides AH1 (accession no. MF037698). The effects of various concentrations of PEN-G and carbon and nitrogen sources on the biotransformation ability at 30°C and pH 7.0 were evaluated. Cells grown in medium supplemented with glucose as an additional carbon source and yeast extract as a nitrogen source exhibited maximal PEN-G biotransformation efficiency and rate (71.678% ±1.28 and 2.99 mg/h, respectively). The culture conditions for B. pseudomycoides AH1 cells were optimized using a Plackett–Burman design (PBD). Six key determinants (p < 0.05) significantly affected the process outcome, as deduced by regression analysis of the PBD data, and modified MSM broth achieved PEN-G biotransformation efficiency (100%) under aerobic shaking conditions at 35°C, irrespective of HPLC analysis. Additionally, the present investigation could strongly support the application of immobilization approaches for the removal of PEN-G-contaminated environmental sites. To the best of the authors’ knowledge, this is the first detailed study on the efficient biotransformation of PEN-G by an alginate-bacteria system as a simple, green, and inexpensive process, as well as a promising method.
{"title":"Eco-friendly biotransformation of penicillin G by free and immobilized marine halophilic Bacillus pseudomycoides AH1","authors":"Aida M. Farag, Hasnaa E-B. Ghonam, Aliaa M. El-Borai","doi":"10.1186/s13213-024-01774-7","DOIUrl":"https://doi.org/10.1186/s13213-024-01774-7","url":null,"abstract":"Several antibiotics are partially metabolized by patients after administration and end up in municipal sewage systems. The fate of biodegradation in aquatic environments and the role of biodegradation in the development of bacterial resistance are poorly understood. Thus, as a crucial step in an environmental risk assessment, the biodegradability of many therapeutically significant antibiotics was investigated. A marine halophilic bacteria that degrades penicillin G (PEN-G) was isolated and identified based on morphology, physio-biochemical characteristics, and 16S rDNA sequences as Bacillus pseudomycoides AH1 (accession no. MF037698). The effects of various concentrations of PEN-G and carbon and nitrogen sources on the biotransformation ability at 30°C and pH 7.0 were evaluated. Cells grown in medium supplemented with glucose as an additional carbon source and yeast extract as a nitrogen source exhibited maximal PEN-G biotransformation efficiency and rate (71.678% ±1.28 and 2.99 mg/h, respectively). The culture conditions for B. pseudomycoides AH1 cells were optimized using a Plackett–Burman design (PBD). Six key determinants (p < 0.05) significantly affected the process outcome, as deduced by regression analysis of the PBD data, and modified MSM broth achieved PEN-G biotransformation efficiency (100%) under aerobic shaking conditions at 35°C, irrespective of HPLC analysis. Additionally, the present investigation could strongly support the application of immobilization approaches for the removal of PEN-G-contaminated environmental sites. To the best of the authors’ knowledge, this is the first detailed study on the efficient biotransformation of PEN-G by an alginate-bacteria system as a simple, green, and inexpensive process, as well as a promising method.","PeriodicalId":8069,"journal":{"name":"Annals of Microbiology","volume":"6 1","pages":""},"PeriodicalIF":3.0,"publicationDate":"2024-08-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142221083","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In recent years, there has been an increasing interest in the field of research into the isolation and characterization of probiotics in the prevention of diseases and the need to maintain the continuity of healthy microbiota. Therefore, the aim of this study is to isolate and identify bacteria found in maternal colostrum, breast milk, adult and infant feces, analyze possible probiotic potential, and reveal the developmental kinetics of selected strains. We isolated 40 bacterial species from 4 different sources and identified 19 bacteria in the form of bacilli through molecular biology and carried out studies with 11 of them. Five of the selected strains showed the better results considering bile salt resistance and ability to survive at different pH and antimicrobial effect. When the adhesion capacity in cell culture is examined, the better 2 strains are; Lactobacillus pontis ZZ6780 and Lactobacillus reuteri NBC2680 were selected and the growth kinetics of these strains were demonstrated at the 3 L bioreactor scale. Finally, the growth kinetics of selected strains were determined and the maximum specific growth rate of selected Lactobacillus pontis ZZ6780 and Lactobacillus reuteri NBC2680 was calculated as 0.412 h− 1 and 0.481 h− 1, respectively. In addition, the dry cell matter amounts were found to be and 4.45 g/L and 5.23 g/L, respectively. This study established the groundwork for the selection of safety probiotics for the development and application of LAB. It is thought that the two strains obtained as a result of this study can be considered as potential probiotic strains in the food, pharmaceutical and cosmetic industries.
{"title":"Characterization of nuvita biosearch center (NBC) isolated lactic acid bacteria strains from human origin and determination of growth kinetic profiles of selected cultures under bioreactor","authors":"Akif Emre Kavak, İnci Zent, Ezgi Metin Sağır, Gülistan Öncü, Feride İrem Şimşek","doi":"10.1186/s13213-024-01772-9","DOIUrl":"https://doi.org/10.1186/s13213-024-01772-9","url":null,"abstract":"In recent years, there has been an increasing interest in the field of research into the isolation and characterization of probiotics in the prevention of diseases and the need to maintain the continuity of healthy microbiota. Therefore, the aim of this study is to isolate and identify bacteria found in maternal colostrum, breast milk, adult and infant feces, analyze possible probiotic potential, and reveal the developmental kinetics of selected strains. We isolated 40 bacterial species from 4 different sources and identified 19 bacteria in the form of bacilli through molecular biology and carried out studies with 11 of them. Five of the selected strains showed the better results considering bile salt resistance and ability to survive at different pH and antimicrobial effect. When the adhesion capacity in cell culture is examined, the better 2 strains are; Lactobacillus pontis ZZ6780 and Lactobacillus reuteri NBC2680 were selected and the growth kinetics of these strains were demonstrated at the 3 L bioreactor scale. Finally, the growth kinetics of selected strains were determined and the maximum specific growth rate of selected Lactobacillus pontis ZZ6780 and Lactobacillus reuteri NBC2680 was calculated as 0.412 h− 1 and 0.481 h− 1, respectively. In addition, the dry cell matter amounts were found to be and 4.45 g/L and 5.23 g/L, respectively. This study established the groundwork for the selection of safety probiotics for the development and application of LAB. It is thought that the two strains obtained as a result of this study can be considered as potential probiotic strains in the food, pharmaceutical and cosmetic industries.","PeriodicalId":8069,"journal":{"name":"Annals of Microbiology","volume":"50 1","pages":""},"PeriodicalIF":3.0,"publicationDate":"2024-07-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141869851","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
: Lactic acid bacteria (LAB) are a cluster of microbes distributed in a variety of environments and have potential probiotic activity to improve human well-being. This study was aimed at assessing the probiotic potential of LAB isolated from Cheka, an Ethiopian traditionally fermented beverage. Pure isolates obtained from 16 Cheka samples from Konso (n = 8) and Derashe (n = 8) were characterized morphologically, biochemically, and physiologically by considering basic criteria to identify the LAB. The probiotics properties of the LAB were evaluated in vitro at low pH values (2.0 and 3.0), and two bile salt concentrations (0.3 and 0.5%) for 3 and 6 h. The 16 S rRNA gene sequencing was done using an ABI 3730xl sequencer, and the gene sequences were aligned. Of the 27 pure isolates, 11 isolates were proven to be LAB with non-motile, negative for catalase, and non-spore former characteristics. Based on cultural characteristics and sugar fermentation ability, the 11 isolates were assembled into the genera Lactobacillus (55%), Lactococcus (18%), Pediococcus (18%), and Leuconostoc (9%). At pH 3.0 and a bile salt concentration of 0.3%, isolate ChK-11 showed a better survival rate (97 and 94%) than other isolates [ChK-7 (93 and 80%) > ChD-5 (84 and 76%) > ChD-8 (46 and 36%) > ChK-4 (41 and 34%)] for 6 and 3 h, respectively. According to 16 S rRNA sequencing results, isolates ChK-11 and ChK-7 were found to be Weissella paramesenteroides and Leuconostoc pseudomesenteroides with sequence similarity of 99 and 91%, respectively. In the present study, probiotic LAB (Weissella paramesenteroides and Leuconostoc pseudomesenteroides) was successfully isolated and sequenced from Cheka samples. The findings of this in vitro study indicated that fermented beverages like Cheka are a source of the LAB with probiotic functional properties. Overall, Weissella paramesenteroides and Leuconostoc pseudomesenteroides isolates, which showed promising probiotic properties under in vitro conditions, can be used for starter culture development for the Cheka fermentation process.
{"title":"Probiotic potential of lactic acid bacteria isolated from Ethiopian traditional fermented Cheka beverage","authors":"Dawit Albene, Niguse Kelile Lema, Getaneh Tesfaye, Addisu Fekadu Andeta, Kidist Ali, Awoke Guadie","doi":"10.1186/s13213-024-01771-w","DOIUrl":"https://doi.org/10.1186/s13213-024-01771-w","url":null,"abstract":": Lactic acid bacteria (LAB) are a cluster of microbes distributed in a variety of environments and have potential probiotic activity to improve human well-being. This study was aimed at assessing the probiotic potential of LAB isolated from Cheka, an Ethiopian traditionally fermented beverage. Pure isolates obtained from 16 Cheka samples from Konso (n = 8) and Derashe (n = 8) were characterized morphologically, biochemically, and physiologically by considering basic criteria to identify the LAB. The probiotics properties of the LAB were evaluated in vitro at low pH values (2.0 and 3.0), and two bile salt concentrations (0.3 and 0.5%) for 3 and 6 h. The 16 S rRNA gene sequencing was done using an ABI 3730xl sequencer, and the gene sequences were aligned. Of the 27 pure isolates, 11 isolates were proven to be LAB with non-motile, negative for catalase, and non-spore former characteristics. Based on cultural characteristics and sugar fermentation ability, the 11 isolates were assembled into the genera Lactobacillus (55%), Lactococcus (18%), Pediococcus (18%), and Leuconostoc (9%). At pH 3.0 and a bile salt concentration of 0.3%, isolate ChK-11 showed a better survival rate (97 and 94%) than other isolates [ChK-7 (93 and 80%) > ChD-5 (84 and 76%) > ChD-8 (46 and 36%) > ChK-4 (41 and 34%)] for 6 and 3 h, respectively. According to 16 S rRNA sequencing results, isolates ChK-11 and ChK-7 were found to be Weissella paramesenteroides and Leuconostoc pseudomesenteroides with sequence similarity of 99 and 91%, respectively. In the present study, probiotic LAB (Weissella paramesenteroides and Leuconostoc pseudomesenteroides) was successfully isolated and sequenced from Cheka samples. The findings of this in vitro study indicated that fermented beverages like Cheka are a source of the LAB with probiotic functional properties. Overall, Weissella paramesenteroides and Leuconostoc pseudomesenteroides isolates, which showed promising probiotic properties under in vitro conditions, can be used for starter culture development for the Cheka fermentation process.","PeriodicalId":8069,"journal":{"name":"Annals of Microbiology","volume":"49 1","pages":""},"PeriodicalIF":3.0,"publicationDate":"2024-07-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141753940","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Rot disease caused by Fusarium poses a formidable threat to the growth of saffron (Crocus sativus L.), resulting in substantial damage to both yield and quality. It is paramount to delve into the root causes of rot disease in saffron to optimize both yield and quality. Existing preventive and treatment modalities have exerted deleterious effects on corms and the natural environment. Consequently, the quest for efficacious and eco-friendly methods such as biological control agents has become an urgent imperative. The disparate distribution of microbial communities between rhizospheric microorganisms and saffron serves as the foundational exploration for uncovering the underlying causes of rot disease. Samples from various saffron organs and rhizosphere soil were gathered, and the sequencing data from the microbial communities were interpreted using 16S rRNA and ITS gene sequencing methods. This facilitated an in-depth examination of the composition and changes of microorganisms in both healthy and diseased saffron plants. The findings indicated rot disease reduced the abundance and diversity of microorganisms in saffron, and the fungal co-occurrence networks were less stable and their communities were more sensitive to rot disease than the bacterial community. Fusarium was the predominant genus in diseased samples, accounting for 99.19% and 89.77% of the communities in diseased leaves and corms. With corms and leaves displaying heightened susceptibility to infection compared to other plant organs. Some of the beneficial bacterial taxa enriched in the diseased plants were also identified in networks, they showed an antagonistic relationship with Fusarium, suggesting a potential for these bacteria to be used in biologically based control strategies against rot disease. These insights could prove invaluable for the development of biocontrol agents aimed at combating this plant ailment. These findings significantly advance our understanding of saffron-microbiome interactions and could provide fundamental and important data for improving saffron yield and quality in the process of sustainable development.
{"title":"Revealing the microbial composition changes and relationship with Fusarium caused by rot disease in the Crocus sativus L.","authors":"Jia Song, Xiaoyuan Xi, Xiaodong Qian, Jing Li, Yuanyuan Tao, Liqin Li, Guifen Zhou","doi":"10.1186/s13213-024-01770-x","DOIUrl":"https://doi.org/10.1186/s13213-024-01770-x","url":null,"abstract":"Rot disease caused by Fusarium poses a formidable threat to the growth of saffron (Crocus sativus L.), resulting in substantial damage to both yield and quality. It is paramount to delve into the root causes of rot disease in saffron to optimize both yield and quality. Existing preventive and treatment modalities have exerted deleterious effects on corms and the natural environment. Consequently, the quest for efficacious and eco-friendly methods such as biological control agents has become an urgent imperative. The disparate distribution of microbial communities between rhizospheric microorganisms and saffron serves as the foundational exploration for uncovering the underlying causes of rot disease. Samples from various saffron organs and rhizosphere soil were gathered, and the sequencing data from the microbial communities were interpreted using 16S rRNA and ITS gene sequencing methods. This facilitated an in-depth examination of the composition and changes of microorganisms in both healthy and diseased saffron plants. The findings indicated rot disease reduced the abundance and diversity of microorganisms in saffron, and the fungal co-occurrence networks were less stable and their communities were more sensitive to rot disease than the bacterial community. Fusarium was the predominant genus in diseased samples, accounting for 99.19% and 89.77% of the communities in diseased leaves and corms. With corms and leaves displaying heightened susceptibility to infection compared to other plant organs. Some of the beneficial bacterial taxa enriched in the diseased plants were also identified in networks, they showed an antagonistic relationship with Fusarium, suggesting a potential for these bacteria to be used in biologically based control strategies against rot disease. These insights could prove invaluable for the development of biocontrol agents aimed at combating this plant ailment. These findings significantly advance our understanding of saffron-microbiome interactions and could provide fundamental and important data for improving saffron yield and quality in the process of sustainable development.","PeriodicalId":8069,"journal":{"name":"Annals of Microbiology","volume":"64 1","pages":""},"PeriodicalIF":3.0,"publicationDate":"2024-07-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141745850","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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