【摘要】 为了筛选动物肠道中的有益优势菌,研究了2株分离自猪肠道的益生性屎肠球菌(E1,E7)的耐受特性。本试验设pH 2,2.5,3,4的4个处理组,以pH 7为对照组;设胆盐浓度分别为0.2%,0.4%,0.6%,0.8%,1%的5个处理组,以不含胆盐的培养液为对照组;温度设50,80,90℃,以37℃为对照,分别作用5,10,15,20 min,经该3种方法处理后各取100μL培养液用细菌稀释计数法测定活菌数。结果表明:E1,E7都有较强的耐酸能力,在pH 2时,作用2 h后仍能检测到活菌。胆盐浓度达到0.4%时,E1,E7仍有一定的耐受能力,随胆盐浓度升高至0.6%时,活菌数由108.2CFU/mL降到102.5CFU/mL。2菌株在不同温度下经不同作用时间处理后呈不同的生长态势。更多还原

【Abstract】 Tolerance of two strains of Enterococcus faecium from swine intestine to acid,bile salt and thermal tolerance was investigated.The pH value were 2,2.5,3,4,pH7 as the control;The concentration of bile salt were 0.2%,0.4%,0.6%,0.8%,1%,culture fluid of free bile salt as the control;The two strains were treated with 50,80,90 ℃ for 5,10,15,20 min respectively,100 μL of culture solution from three kinds of disposals,were obtained to determine the survival counts by dilution method of bacteria counting.The results showed that E1 and E7 had significant acid resistance,the survival counts of E1 and E7 could be detected when pH value was at 2 after two hours.The survival counts of E1 and E7 could be detected when incubated in medium with 0.4% bile salt,but declined from 108.2CFU/mL to 102.5CFU/mL while the concentration of bile was increased to 0.6%.更多还原