摘要
目的:从母乳婴儿粪便筛选获得产广谱细菌素的乳酸菌菌株,并对其所产细菌素的理化及生物学特性进行研究分析,预测其在食品工业中的应用前景。方法:以课题组从母乳婴儿粪便分离得到的23株乳酸菌为试材,采用牛津杯琼脂扩散法,选取单增李斯特氏菌(Listeria monocytogenes)和大肠杆菌(Escherichia coli)为指示菌筛选产广谱细菌素的优良菌株。通过菌体形态观察、生理生化特征及16S r DNA序列分析对菌株进行分类学鉴定,并从耐酸、耐热、蛋白酶敏感性、抑菌谱等角度分析菌株所产细菌素生物学特性。结果:分离得到1株产广谱细菌素菌株BL-1,发现该菌株所产细菌素具有较好的热稳定性和酸耐受性,在pH为2、121℃条件下细菌素活性仍然保持稳定,酶敏感性强,胃蛋白酶可将其完全分解,使用安全性较高,且抑菌谱较广,对受试的李斯特菌(Listeria monocytogenes)、金黄色葡萄球菌(Staphylococcus aereu)等革兰氏阳性菌和大肠杆菌阴性菌均表现出较强抑菌活性。最后该菌株经分类学鉴定为鼠李糖乳杆菌(Lactobacillus rhamnosus)。结论:从母乳婴儿粪便中分离出一株产广谱细菌素鼠李糖乳杆菌BL-1,该菌所产细菌素具有优良的食品加工特性,有作为天然食品防腐剂的巨大应用前景。
Objective ：To obtain a broad spectrum of bacteriocin-producing lactic acid bacteria strains from breastfeeding baby stool, researching and analyzing its physicochemical and biological properties of bacteriocins,predict its potential applications in the food industry. Methods：The antimicrobial activity of 23 Lactobacillus strains isolated from breastfeeding infant faeces was tested by the oxford cup agar diffusion method using Listeria monocytogenes and E. coli as indicator bacteria. The strains were identified by cell morphological,physiological,biochemical characteristics and 16 S r DNA sequence analysis,and from the acid,heat,protease sensitivity,antibacterial spectrum angles,analyze the biological characteristics of bacteriocins.Results：A broad spectrum bacteriocin producing strains BL-1 was isolated in this study. And results showed its bacteriocins have strong thermal stability and acid tolerance. Under the conditions of pH of 2,121℃,the bacteriocin activity remained stable and the pepsin could be completely decomposed it. And this bacteriocin showed the higher security and broad spectrum antimicrobial,the inhibitory effect was very obvious against Listeria monocytogenes,Staphylococcus aureus and other Gram-positive and negative bacteria such as Escherichia coli. Finally,it was identified as Lactobacillus rhamnosus. Conclusion：In this study,we isolated a broad spectrum bacteriocin producing Lactobacillus rhamnosus BL-1,and we found that its bacteriocin had excellent biological characteristics and great application prospects on the development of natural biological preservatives.
出处
《食品工业科技》
CAS
CSCD
北大核心
2015年第4期180-184,198,共6页
Science and Technology of Food Industry
基金
北京市自然科学基金预探索项目(5133034)
国家自然科学基金青年基金项目(31201407)
国家十二五科技支撑项目(2013BAD18B12-05)
关键词
鼠李糖乳杆菌
细菌素
鉴定
特性
Lactobacillus rhamnosus bacteriocin identification characteristics
