一株曲拉源短乳杆菌的分离及其体外抑菌特性分析

Isolation of a strain of Lactobacillus brevis from Qula and analysis of its antibacterial properties in vitro

中文关键词:  曲拉  短乳杆菌  筛选与鉴定  抑菌活性

英文关键词:Qula  Lactobacillus brevis  screening and identification  antibacterial activity

中文摘要:

      目的 从曲拉中分离筛选出具有优良抑菌活性的乳酸菌, 并对其特性进行分析评价。方法 以西藏牦牛乳曲拉为分离基质, 乳酸细菌培养基加上1%碳酸钙为选择鉴别培养基, 运用形态学观察、生理生化试验、16S rRNA基因序列鉴定菌株, 通过药敏试验对分离菌株进行耐药性分析以及抑菌试验探究其抑菌活性。结果 分离菌株NWMCC0322被鉴定为短乳杆菌(Lactobacillus brevis), 其对阿莫西林、氨苄西林、四环素、红霉素、氯霉素、阿米卡星、磺胺甲恶唑、头孢噻吩、头孢他啶药物敏感, 对两性霉素B中介。NWMCC0322对指示菌金黄色葡萄球菌的抑菌效果最好, 其抑菌圈直径达(12.0±0.6) mm, 其次为甲型副伤寒沙门氏菌(11.3±0.3) mm, 大肠杆菌(11.0±0.5) mm。结论 该短乳杆菌对食品污染常见菌株具有抑菌效果, 在食品开发中有较好的应用价值。

英文摘要:

      Objective To isolate and screen out a strain of Lactobacillus with excellent antibacterial activity from Qula, and analyze its biological characteristics. Methods Tibetan yak Qula was used as separation matrix, and lactic acid bacteria medium plus 1% calcium carbonate was used as selective identification medium, the strain was identified by morphological observation, physiological and biochemical tests, identified by 16S rRNA gene sequence. The drug resistance of isolated strains was analyzed by drug sensitivity test and antibacterial activity was investigated by bacteriostatic test. Results The isolated NWMCC0322 was identified as Lactobacillus brevis, which was susceptible to amoxicillin, aminobenzylpenicillin, tetracycline, erythromycin, chloramphenicol, amikacin, sulfamethoxazole, cephalothifen, ceftazidime drugs, and intermediate to amphotericin B. NWMCC0322 exhibited the best inhibitory effect on the indicator strain Staphylococcus aureus, with the inhibition zone diameter reaching (12.0±0.6) mm, followed by Salmonella paratyphi A (11.3±0.3) mm, and Escherichia coli (11.0±0.5) mm. Conclusion Lactobacillus brevis has antibacterial effect on common strains of food contamination, and has good application value in food development.