产细菌素双歧杆菌的筛选及其分泌条件研究  

Screening of Bacteriocin-producing Bif idobacterium Strain and Culture Coditions for Bacteriocin Secretion

作　　者：尚楠[1] 王洋[1] 任发政[1] 李平兰[1] 

机构地区：[1]中国农业大学食品科学与营养工程学院,北京100083

出　　处：《食品科学》2013年第23期170-175,共6页Food Science

基　　金：国家自然科学基金项目(31071591)

摘　　要：以32株我国广西巴马长寿老人源双歧杆菌为材料,以植物乳杆菌PL-2为指示菌,经筛选获得1株具有明显抗菌效果的双歧杆菌L-SN。排除有机酸、H2O2等干扰因素,经硫酸铵沉淀粗提,蛋白酶敏感性实验后确定其产生的抗菌物质为细菌素。通过形态学、生理生化以及16S rRNA序列分析鉴定菌株L-SN为动物双歧杆菌乳亚种(Bifidobacterium animalis subsp.lactis L-SN)。进一步研究菌株L-SN产细菌素的生物学特性,确定其最佳分泌细菌素条件为起始pH6.5、培养温度30℃、培养时间28h。在此基础上,考察菌株L-SN所产细菌素的抗菌谱,发现其具有广谱的抗菌效果,尤其对金黄色葡萄球菌、单增李斯特氏菌等致病菌有显著的作用,显示出该双歧杆菌的潜在开发应用前景。Bifidobacterium L-SN capable of producing an antimicrobial substance that was effective against Lactobacillus plantarum PL-2 was screened from 32 strains of Bifidobacterium isolated from the feces of centenarians in Bama county of Guangxi region. By eliminating the effects of organic acid and H202, we confirmed the antimicrobial role because of bacteriocin. Based on morphological, physiological and biochemical characteristics and 16S rRNA sequence analysis, the strain L-SN was identified as Bifidobacterium animalis subsp, lactis. We investigated the secretion characteristics of Bifidobacterium animalis L-SN and established the optimum incubation conditions for producing bacteriocin： 28 h of culture at 30℃ and initial medium pH 6.5. The bacteriocin had a wide spectrum of antibacterial activities against Gram-positive and Gram-negative bacteria, especially against Staphylococcus aureus, Escherichia coli and Listeria monocytogenes showing a potential application prospect.

关 键 词：双歧杆菌 筛选 细菌素 分泌特性 

分 类 号：Q936[生物学—微生物学]