中文摘要：

针对目前海参养殖中水产微生态制剂品种单一、施用效果不稳定等现状,作者从地瓜参（Acaudina molpadioidea）肠道分离土著肠杆菌（Enterobacter）,筛选到1株具有较好拮抗作用的海洋细菌C-5,该菌对副溶血弧菌（Vibrio parahaemolyticus）、溶藻弧菌（Vibrio alginolyticus）、杀鲑气单胞菌（Aeromonas salmonicida）等7种细菌有拮抗作用；通过形态观察、生理生化和16S rDNA基因序列分析鉴定为霍肠杆菌（Enterobacter hor-maechei）；通过卤虫（Artemia）和药敏实验检测该菌具有安全性,其对卤虫的72 h半致死浓度（LC50）为108 cfu/mL,只对20种常规抗生素中的5种产生耐药性；对C-5的发酵条件进行优化,该菌优化后的发酵条件为：温度30℃, pH 7.0,盐度2%。结果表明, C-5有望作为一种益生菌应用于海水养殖病害控制。

英文摘要：

A probiotic strain of nativeEnterobacternamed as C-5 has been isolated from the intestine ofacaudina molpadioidea in this study. By observing colony morphology, analyzing physiological and biochemical characters, and sequencing of 16S rDNA, C-5 was identified asEnterobacter hormaechei. C-5 showed inhibitory activity against seven pathogens, such asVibrio parahaemolyticus,Vibrio alginolyticus,Aeromonas salmonicida. The secu-rity of C-5 was confirmed by theArtemiachallenge test and drug sensitivity tests. The LC50 of C-5 was found to be 108 cfu/mL, and it was resistant to five antibiotics among twenty used. The optimized fermentation condition of C-5 is： temperature 30℃ , pH 7.0, 2% salinity.Our results showed that C-5 could be used as a kind of probiotic applied to aquaculture disease control.