A collection of lactic acid bacteria isolates from fish viscera was studied and investigated regarding to their functional properties and safety aspects. From these, three isolates GM1, GM2 and GM3 were identified as ...A collection of lactic acid bacteria isolates from fish viscera was studied and investigated regarding to their functional properties and safety aspects. From these, three isolates GM1, GM2 and GM3 were identified as Enterococcus feacium species using molecular methods. Partial Amplified rDNA Restriction Analysis (partial ARDRA) with restriction enzyme HaeIII separated these isolates into distinctive group which suggest genotypic variability within enterococci strains isolated from fish viscera. The three strains GM1, GM2 and GM3 exhibited antimicrobial activity. Indeed strains have been shown to produce bacteriocins with inhibitory effect against food spoilage bacteria and pathogenic fish including Carnobacterium maltaromaticum. The molecular mass of bacteriocin, as calculated by tricine-SDS-PAGE, was found to be 4.5 kDa. All isolates were tested positive upon PCR amplification of enterocin A structural gene. Investigations of antibiotic resistance show that the isolates were mostly sensitive to several antibiotics (ampicillin, penicillin, tetracycline, gentamycine) and resistance to rifampicin. All isolates grow in esculin azide agar as a selective medium for enumeration of probiotic enterococci. This study suggests that our strains can be employed as probiotic or to improve the safety of food products.展开更多
Carnobacterium is a genus of Gram-positive bacteria,within family Carnobacteriaceae,and they are catalase-and oxidase-negative,non-sporing bacteria with properties such as CO_(2)and L(+)-lactic acid production from gl...Carnobacterium is a genus of Gram-positive bacteria,within family Carnobacteriaceae,and they are catalase-and oxidase-negative,non-sporing bacteria with properties such as CO_(2)and L(+)-lactic acid production from glucose,but they are not able to grow on acetate agar.They are ubiquitous lactic acid bacteria and have been isolated from both cold and temperate environments,and they are identified as components of the microbiota in the gastrointestinal(GI)tract of salmonids and several other fish species of which Carnobacterium(piscicola)maltaromaticum,Carnobacterium mobile,Carnobacterium divergens,Carnobacterium alterfunitum,and Carnobacterium inhibens are reported.During the last two decades several studies have revealed that carnobacteria can act as probiotics to promote health benefits of fish,as well as they in ex vivo studies to some extent can out-compete pathogens.In addition to beneficial effects,information is available that some carnobacteria species causing fish disease.The aim of the present review is to present an updated overview of Carnobacterium in fish,with focus on their presence in the GI tract,their use as probiotic supplement and general information on pathogenic carnobacteria.展开更多
文摘A collection of lactic acid bacteria isolates from fish viscera was studied and investigated regarding to their functional properties and safety aspects. From these, three isolates GM1, GM2 and GM3 were identified as Enterococcus feacium species using molecular methods. Partial Amplified rDNA Restriction Analysis (partial ARDRA) with restriction enzyme HaeIII separated these isolates into distinctive group which suggest genotypic variability within enterococci strains isolated from fish viscera. The three strains GM1, GM2 and GM3 exhibited antimicrobial activity. Indeed strains have been shown to produce bacteriocins with inhibitory effect against food spoilage bacteria and pathogenic fish including Carnobacterium maltaromaticum. The molecular mass of bacteriocin, as calculated by tricine-SDS-PAGE, was found to be 4.5 kDa. All isolates were tested positive upon PCR amplification of enterocin A structural gene. Investigations of antibiotic resistance show that the isolates were mostly sensitive to several antibiotics (ampicillin, penicillin, tetracycline, gentamycine) and resistance to rifampicin. All isolates grow in esculin azide agar as a selective medium for enumeration of probiotic enterococci. This study suggests that our strains can be employed as probiotic or to improve the safety of food products.
文摘【目的】肠道细菌肉杆菌Carnobacterium maltaromaticum是小菜蛾Plutella xylostella幼虫肠道的可培养优势细菌,本研究旨在阐明肉杆菌的代谢表型特征。【方法】采用BIOLOG细胞表型芯片技术系统地研究了肉杆菌的细胞表型;采用PM1-PM10代谢板,对肉杆菌的950种代谢表型进行了测定。【结果】肉杆菌能代谢34.74%的碳源、99.47%的氮源、100%的硫源和79.66%的磷源;高效代谢的碳源为有机酸类和糖化合物类,高效代谢的氮源为氨基酸类和肽类。该肠道细菌未表现出生物合成途径。肉杆菌具有广泛的适应性,能在分别具有高达10%氯化钠、6%氯化钾、5%硫酸钠、20%乙二醇、6%甲酸钠、7%尿素、8%乳酸钠、200 mmol/L磷酸钠(p H 7.0)、200 mmol/L苯甲酸钠(p H 5.2)、100 mmol/L硫酸铵(p H 8.0)、100 mmol/L硝酸钠和100 mmol/L亚硝酸钠的渗透溶液中正常代谢,不能在9%-12%的乳酸钠渗透溶液中代谢;其适应p H值范围为5-10,最适约为10.0。在多种氨基酸的作用下,肉杆菌仅有脱氨酶活性,而无脱羧酶活性。【结论】肉杆菌的代谢特征增加了我们对该肠道细菌的认识,同时为其功能的研究和其与宿主小菜蛾的互作研究提供了信息基础。
文摘Carnobacterium is a genus of Gram-positive bacteria,within family Carnobacteriaceae,and they are catalase-and oxidase-negative,non-sporing bacteria with properties such as CO_(2)and L(+)-lactic acid production from glucose,but they are not able to grow on acetate agar.They are ubiquitous lactic acid bacteria and have been isolated from both cold and temperate environments,and they are identified as components of the microbiota in the gastrointestinal(GI)tract of salmonids and several other fish species of which Carnobacterium(piscicola)maltaromaticum,Carnobacterium mobile,Carnobacterium divergens,Carnobacterium alterfunitum,and Carnobacterium inhibens are reported.During the last two decades several studies have revealed that carnobacteria can act as probiotics to promote health benefits of fish,as well as they in ex vivo studies to some extent can out-compete pathogens.In addition to beneficial effects,information is available that some carnobacteria species causing fish disease.The aim of the present review is to present an updated overview of Carnobacterium in fish,with focus on their presence in the GI tract,their use as probiotic supplement and general information on pathogenic carnobacteria.
