牙鲆肠道乳酸菌的分离和鉴定

ISOLATION AND CHARACTERIZATION OF LACTIC ACID BACTERIA FROM GASTROINTESTINAL TRACT OF FLOUNDER

目的 :根据微生态学原理 ,从健康牙鲆的肠道固有菌群中分离乳酸菌。方法 :需氧与厌氧培养法。结果 :两种方法获得了不同的结果 ,用 L BS(p H6 .5 )直接分离 ,从 19株分离菌株中只获得 6株乳酸菌 ,其中 1株 P15为乳杆菌 ;而用 L BS(p H5 .4)和 SL(p H5 .4)先富集后分离得到了许多单一的乳杆菌菌落。对所分离的乳杆菌进行生化鉴定 ,均符合该菌的生化特征。牛津杯抑菌试验显示 ,乳酸菌对弧菌均有抑制作用 ,其中乳杆菌 P15在 p H6 .8和 p H7.5生长良好 ,并对弧菌有强力的抑制作用 ;而在 p H 8.0和 p H8.5时该菌生长不良且无抑菌活性。

Objective:Based on the microecological principle,lactic acid bacteria were isolated from the autochthonous flora in gastrointestinal tract of healthy flounders.The results were different as the two methods were used.6 strains of lactic acid bacteria were obtained from 19 strains of intestinal bacteria with the LBS plate (pH6.5) directly.All of the bacteria isolated from LBA plate(pH5.4) and SL plate (pH5.4) afterenrichment were pure Lactobacillus sp .and shown to be the characterization of Lactobacillus .In Oxford cup assay,lactic acid bacteria were shown to have inhibition effect on Vibrio .Among the bacteria, Lactobacillus strain P15 has great growth rate and powerful inhibition activity in pH6.8 and pH7.5.But no any inhibition activity in pH8.0 and pH8.5.