副溶血弧菌噬菌体微胶囊的制备及在饵料中的应用

Preparation of Vibrio parahaemolyticus Phage Microencapsulation and Its Usage in Aquatic Feeds

采用复相乳液法,以乙基纤维素为包囊材料,明胶溶液为保护液制取微胶囊,对副溶血弧菌噬菌体(Vibrio parahaemolyticus phage)进行固定化,制备噬菌体微胶囊。结果显示,乙基纤维素质量浓度为30 g/L,明胶质量浓度为20 g/L,搅拌速度为600 r/min,时间30 min,副溶血弧菌噬菌体悬液与乙基纤维素溶液的体积比为1∶3时,所得微胶囊有较好的噬菌体缓释性能,综合评价指数最高。对方斑东风螺(Babylonia areolata)饲以混有噬菌体微胶囊的饵料,当饵料中噬菌体微胶囊质量分数为1.0 g/kg时,与对照组比较,东风螺肠道宿主菌平均减少96%,水体中宿主菌减少72%,差异均有统计学意义(P<0.05);以黏附剂按1.5 g/kg的剂量将噬菌体微胶囊黏附于对虾饵料,并投喂凡纳滨对虾(Litopenaeus vannamei),对虾肠道的宿主菌比对照组平均减少86%,水体中宿主菌比对照组减少68%,差异均有统计学意义(P<0.05)。微胶囊可有效控制宿主弧菌的在养殖体系的浓度,减少养殖动物弧菌病的产生。

Vibrio parahaemolyticus phage was microcapsulated by the method of intra-liquid desiccation using ethyl-cellulose（EC） as coating material and glutin as protective agent. The influence of EC concentration, stirring rate, the ratio of drug to EC and the concentration of protective agent to the microencapsulation was verified. Through the single factor test and the orthogonal test, the best preparation technique was that： stirring rate was 600 r/min and the time was 30 minutes, and the ratio of drug to EC was 1 to 3, and the EC concentration was 3% and the concentration of protective agent was 2%. The microcapsulated Vibrio parahaemolyticus phage was added into the feed of Babylonia areolata and Litopenaeus vannamei. 24 hours after giving this feeds, compared with the control, the host vibrio in the intestinal tract of Babylonia areolata decreases by 96%, and that in the intestinal tract of Litopenaeus vannamei decreases by 86%, and that in the water culturing Babylonia areolata decreases by 72%, and 68% in the water culturing Litopenaeus vannamei, and the difference between experimental and control group was statistical at level ofP〈0.05. It is suggested that the microcapsulated Vibrio parahaemolyticus phage could diminish the amount of V. parahaemolyticus in water and the intestinal of the cultured animals.