牛瘤胃乳酸菌的分离与鉴定

为分离筛选用于牛活菌制剂的乳酸菌菌株，试验采用API 50CHL对从牛瘤胃中分离的60株乳酸菌进行生化鉴定，对鉴定出的菌株进行耐酸耐碱、生长温度、耐氧、耐药和抑菌性测定。结果显示，经生化鉴定出的3株菌分别为嗜酸乳杆菌（L.acidophilus）、发酵乳杆菌（L.fermentum）和乳明串珠菌（L.holzapfelii），分别命名为L1、L2和L3。其中，L1耐酸性最强，L2耐碱性最强，L1在37～40 ℃之间均生长良好且兼性厌氧；L1、L2、L3耐药率为60%～100%；3株乳酸菌对大肠杆菌和金黄色葡萄球菌均有不同程度的抑制作用，其中L1抑菌效果最好，抑菌圈直径分别为18.30和16.40 mm。提示，L1、L2可作为抗性乳酸菌活菌制剂的候选菌株。

Isolation and Identification of Lactic Acid from Bovine Rumen

To screen and separate viable preparations for bovine strains of lactic acid bacteria，this separated lactic acid bacteria from bovine rumen were identified by API 50CHL.For biochemical identification of strains by resistance for oxygen，acid and alkali，determination of the growth temperature, drug resistance and antibacterial property.The results showed that the three strains of lactic acid bacteria have been identified，which were L. acidophilus （L1）, L. fermentum （L2） and L. holzapfelii （L3）, respectively. L1 had strongest acid，L2 had strongest alkali，L1 was strong in 37 to 40 ℃ were grown between good and facultative anaerobic，the drug resistance rate of L1，L2 and L3 was 60% to 100%.The three strains compare with the Escherichia coli and Staphylococcus showed their inhibition，the L1 had the best bacteriostatic effect，the antibacterial diameter of 18.30 and 16.40 mm，respectively.In conclusion，L1 and L2 will be a candidate viable lactic acid bacteria strains resistant formulations.