拮抗嗜水气单胞菌菌株的筛选及生长条件的优化研究

Isolation of Aeromonas Hydrophila from Ctenopharyngodon Idellus Epibiont and Its Optimal Growing Conditions

以草鱼为研究材料,取其体表微生物进行分离,筛选以嗜水气单胞菌(Aeromonas hy-drophila)为拮抗指示菌的菌株,通过拮抗试验筛选到编号为S190的目标菌株。对S190的生长条件进行优化研究,单因素试验表明其最佳生长条件为糊精质量分数1%,酵母粉质量分数0.1%,K2HPO4或Na2HPO40.01 mol/L,NaCl质量分数为5%,温度为25℃,pH为10,属嗜碱性细菌,接种量以体积分数3%为最佳,装液量对S190的生长无明显影响;正交试验表明其最佳生长条件为糊精质量分数3%,氮源为酵母粉(质量分数0.2%),磷源为K2HPO4(0.02 mol/L)。S190生长曲线表明在最优生长条件下其延滞期明显缩短而很快到达稳定期。

A strain named S190 was isolated from Ctenopharyngodon idellus epibiont samples and its antagonistic effect was available to Aeromonas hydrophila. Further studies showed that the opti- mal conditions for the growth of S190 were as follows： 1% dextrin, 0. 1% yeast extract, 0. 01 mol/L K2HPO4 or Na2HPO4, NaC1 5%, pH 10 and 25 ℃, and also the inoculated volume 3% when simple factor was tested. Orthogonal tests showed that the optimal conditions were 3% dextrin, 0. 2% yeast extract, and 0.02 mol/L Kz HPO4. A contrast of the curve of S190 growing at the optimal conditions with LB showed that the optimal conditions could shorten the time for S190 to get the effective result.