嗜酸乳杆菌在模拟胃肠环境中抗性的研究

采用MRS培养基,模拟胃肠环境,即低pH值（1.5～4.5）。高胆汁盐（0.1％～0.4％）对嗜酸乳杆菌抗性进行了研究。同时对肠道中致病性大肠杆菌、金黄色葡萄球菌的拮抗特性以及服用抗生素后嗜酸乳杆菌的耐药性进行了研究。结果表明,嗜酸乳杆菌在pH2.5～4.5时具有较强的生存能力,6h活菌数仍达 10⁷cfu/mL以上,pH1.5条件下仍有部分存活。在0.1％～0.3％胆汁盐条件下4h活菌数仍达106cfu/mL以上,且能在0.4％胆汁盐中存活。同时,对致病性大肠杆菌和金黄色葡萄球菌具

STUDIES ON THE ANTAGONISTIC PROPERTIES OF LACTOBACILLUS ACIDOPHILUS IN THE IMITATIVE GASTROENTERIC ENVIRONMENT

Using MRS medium, as imitating gastroenteric environments, such as low pH (1.5-4.5) and high bile salt (0.1%~0.4%), the antagonistic properties of Lactobacillus acidophilus were studied. At the same time, the antimicrobial activities on pathogenic E. coli and S. aureus in the intestinal tract and antibiotic tolerance of Lacto-bacillus acidophilus were also studied. The results indicated that Lactobacillus acidophilus survived at pH 2.5 - 4.5 after 6h culture and the living bacterial number could reach 107cfu/mL. One strain even survived at pH 1.5; that living bacterial number were above 106cfu/mL at the 0.1% -0.3% bile salt and a strain survived in 0.4% after 4h culture; that antimicrobial activities to the pathogenic E. coli and 5. aureus were obvious; and that the tolerance to Penicillin and Roxithromycin was medium and power.