牙鲆肠道内弧菌拮抗菌的分离与筛选

ISOLATION AND SCREEN OF Vibrio-ANTAGONISTIC BACTERIA FROM GASTROINTESTINAL TRACT OF FLOUNDER

根据微生态学原理 ,用普通培养基和选择性培养基相结合的方法 ,分离健康牙鲆肠道内的固有菌群。对获得的菌株进行弧菌的抑制试验 ,以筛选弧菌拮抗菌。用点种法初步筛选出6株对致病性弧菌有不同抑制作用的拮抗细菌 (G12 ,G13 ,G14 ,G15 ,G16 ,Y1 13)。进一步研究它们的抑菌活性 ,在上清液抑菌试验中 ,G12,G13,G14,G15,G16这5株菌均未表现出抑菌作用 ,表明它们的抑菌活性较弱 ,而且受环境条件的影响。在Y1 13和弧菌的混合培养实验中 ,弧菌的数量均明显低于对照组弧菌的数量 ,表明Y1 13对弧菌具有较强的抑制作用,有望通过生物学和鱼体保护等方面的研究,将其制成微生态制剂应用于牙鲆的养殖。

Based on the microecological principles, some bacterial strains were isolated and screened from the autochthonous flora of flounders' intestine with the common medium and selective medium for the screen of antagonistic bacteria against Vibrio sp.. In dot inoculation assays, 6 strains (G12, G13, G14, G15, G16 and Y1 13) were screened to inhibit the growth of pathogenic Vibrio to marine fish. In their further study, no antibacterial activities were shown in supernatant inhibition assay with these strains except Y1 13. It was indicated that the antibacterial activities were weaker and were affected by some conditions. In coculture assay, the number of Vibrio in tests was smaller than that of the contract Vibrio group throughout the experiments. It was demonstrated that the Y1 13 was strong antagonistic to Vibrio and it would be used in flounder as ecological preparation be means of its biological characterization and protection against diseases.