【摘要】 目的 :鉴定和筛选 β-半乳糖苷酶高产酶保加利亚乳杆菌。方法 :采用涂片染色和形态特征观察 ,鉴别生化试验 ,(如过氧化氢酶试验、碳水化合物发酵产酸试验及牛奶石蕊试验 )对购买的保加利亚乳杆菌 1.14 80 ,保加利亚乳杆菌 6 0 32和从酸奶中分离的保加利亚乳杆菌进行鉴定 ;采用 X- gal定性试验和 ONPG定量试验对酶活性进行测定以筛选高产酶菌株。结果 :1保加利亚乳杆菌 1.14 80和从酸奶中分离的保加利亚乳杆菌均为保加利亚乳杆菌 ,保加利亚乳杆菌 6 0 32已发生变种。2保加利亚乳杆菌 1.14 80和从酸奶中分离的保加利亚乳杆菌均可在含有 X- gal和 IPTG琼脂培养基上产生蓝色菌落。进一步的定量试验表明保加利亚乳杆菌 1.14 80比从酸奶中分离的保加利亚乳杆菌酶活性高。结论 :从酸奶中分离的保加利亚乳杆菌在作为酸奶菌种的过程中可能被人工训化 ;保加利亚乳杆菌 1.14 80的特性与伯杰手册第八版中描述的完全一致 ,且产酶量最高更多还原

【Abstract】 Objective:In order to authenticate the bulgaria lactobacillus from which β galactosidase gene comes from and screen the bacterium which produces large quantity of β galactosidase.Methods:Gram stain and morphology,H 2O 2 enzyme,carbogydrates fermentation to produce acid and the litmus milk test were performed.By using X gal test and ONPG test,the β galactosidase activity quality and quantity were detected respectively.Results:Bulgaricus Lactobacillus 1 1408 and Bulgaricus Lactobacillus selected from the yoghourt were all Bulgaricus Lactobacilli,but the characters of Bulgaricus Lactobacillus 6032 had changed.Bulgaricus Lactobacillus 1 1480 and Bulgaricus Lactobacillus selected from the yoghourt appeared blue colour on the argar plate containing X gal.And Bulgaricus Lactobacillus 1 1480 produced high quality and large quantity of β galactosidase.Conclusion:Bulgaricus Lactobacillus selected by us could have been tamed during being used as the starter of the yoghourt.The characters of Bulgaricus Lactobacillus 1 1480 are consistent with the phenotypes in Bergeys manual of determinative bacteriology,and the β galactosidase activity is the best of these three bacteria.So the DNA of Bulgaricus Lactobacillus 1 1480 was utilized as the template in the following tests.更多还原