人源乳酸杆菌耐酸耐胆盐能力的测定和鉴定

STUDIES ON THE ANTAGONISTIC PROPERTIES OF LACTOBACILLI FROM HUMAN TO ACID AND BILE SALT AND ITS SYSTEMATIC BIOCHEMICAL IDENTIFICATION.

目的：通过模拟正常人体胃内状态,探讨所筛选4株人源乳酸杆菌耐酸耐胆盐的能力,并进行系统生化鉴定.方法：乳酸杆菌在不同pH值（pH2～4.5）和不同浓度胆盐（0.1%～0.3%）的MRS肉汤中培养4 h后,测定其活菌数及存活率.用API50CHL微量生化反应试剂盒进行菌种鉴定.结果：4株乳酸杆菌能够耐受pH 3的酸度（存活率6.6%～71.8%）和0.3%的胆盐（存活率9.2%～31.8%）,其中22号菌和31号菌在pH 4～4.5的环境中能保持生长活性.12号菌和31号菌耐受胆盐的能力较强.经鉴定,其中3株为唾液乳酸菌,1株为植物乳酸菌.结论：株乳酸杆菌均表现出较好的耐酸耐胆盐能力,其中以12号菌耐受能力最强,有必要进一步评价其体内生存活性.

Objective： To study the acid and bile salt tolerance and biochemical properties of 4 strains of Laetobacilli, originally isolated from human. Methods： Culture the Laetobacillus in the MRS broth with different pH （2.0--4.5） and bile salt （0.1%- 0.3 % ） at 3712 for 4 hours then calculate the livability of Lactobacilli. API 50 CHL was used to identify the lactobacilli species. Resuits： Four stains of Lactobacilli could survive in MRS broth with pH 3.0 （the livabilities are 6.6 % --71.8% ）, or 0.3 % bile salt concentration （the livabilities are 9.2% --31.8%）. Lac-22 and Lac- 31 could keep the livingness at pH 4--4.5, and Lac- 12 and Lac-31 have the best antagonistic properties in bile salt. Three of the four Lactobacilla were identified as Lactobacillus salivarius, and the other one was identified as Lactobaeillus plantarum. Conclusions： The strains were able to endure the differ concentra- tion of acid and bile salt, Lac- 12 has the best antagonistic properties.