作　　者： ; (郭婧）; (宋增福）; (贾亮）; (张永华）; (范斌）; (张庆华）;

机构地区： 上海海洋大学水产与生命学院

出　　处： 《水产学报》 2013年第10期1564-1571,共8页

摘　　要： 从健康养殖大黄鱼肠道中筛选出对病原弧菌有拮抗作用的潜在益生菌株X93,利用细菌快速鉴定系统和16S rDNA方法进行细菌种类鉴定;通过点种法对其抗菌谱进行测定;采用平板扩散法,研究了培养时间、温度、盐度、蛋白酶K和Fe3+等因素对其胞外产物抑菌活性的影响。结果显示:该菌株为短小芽孢杆菌(GenBank accession No.HM137033);对20株病原指示菌中的13株均产生不同程度的抑制作用,抗菌谱较广;菌株培养48 h后的胞外产物抑菌作用最强;在pH为7时,抑菌活性最大;达到最大抑菌活性的温度和盐度分别为28℃、5;蛋白酶K和不同浓度的FeCl3均会降低其抑菌活性。该菌对病原弧菌、迟缓爱德华菌和嗜水气单胞菌等水产上常见主要致病菌有良好的拮抗效果,且具有抑菌作用的胞外产物对温度、盐度和Fe3+有一定的适应范围,适宜作为益生菌株,有望在实际养殖环境中得到应用。 Vibriospecies are the causative agents for vibriosis,the most serious aquaculture disease worldwide.Probiotics are well known to have the potential for broad use in aquaculture environments.In this study,the aim is to screen the probiotic candidate strain from the intestinal tract of healthy,aquaculture-raised large yellow croaker（Pseudosciaena crocea）for the aquaculture.We identified the strain by rapid identification system and 16S rDNA gene sequence analysis.Based on the both identification results,strain X93 was identified as Bacillus pumilus（GenBank accession No.HM137033）.We also checked its antagonistic activities against pathogenic Vibrio parahaemolyticus （Vp-1.2164）and Vibrio alginolyticus （Va-Y）by the dot-inoculating method and tested the effects of temperature,salinity,pH,proteinase K and FeCl3 on the antibacterial activity of the extracellular products.The results indicated that strain X93 could strongly inhibit indicator bacterial strains,such as Vibrio parahemolyticus,Vibrio alginolyticus,Edwardsiella tarda and Aeromonas hydrophila,exhibiting a very broad antibacterial spectrum.The cell-free antibacterial extracellular products secreted by strain X93 most strongly inhibited Vibrio parahemolyticus（Vp1.2164）and Vibrio alginolyticus（Va-Y）when X93 was cultured at 28 ℃ and 5 salinity for 48 h.Our data suggest that strain X93′s antibacterial extracellular products exhibit a fairly broad tolerance to pH,temperature,salinity,and FeCl3.The antibacterial activity of the extracellular products,however,is proteinase K-sensitive,indicating that the active components are proteinaceous.In summary,the results presented here demonstrate that Bacillus pumilus strain X93 can be considered a probiotic since its secreted extracellular products are able to inhibit pathogenic Vibrio,which could have useful antibacterial applications.On a broader level,these results point to the potential for isolating bacteria with novel antibacterial activity from cultivated large yellow croaker.Most importantl

关 键 词： 短小芽孢杆菌 抗菌谱 胞外产物 抑菌活性

领　　域： [生物学] [农业科学] [农业科学]