嗜热链球菌自发突变抗噬菌体菌株的选育及其特性  

Selection and characteristics of the Streptococcus thermophilus spontaneous mutant strain of bacteriophage-resistant

作　　者：鞠世颖[1,2] 赵鑫[1,2] 王雪芹[1,2] 赵婷婷[1,2] 霍贵成[1,2] 

机构地区：[1]乳品科学教育部重点实验室,东北农业大学,黑龙江哈尔滨150030 [2]东北农业大学食品学院,黑龙江哈尔滨150030

出　　处：《食品工业科技》2013年第20期216-220,共5页Science and Technology of Food Industry

基　　金：国家自然基金项目(31171717)

摘　　要：以酸奶发酵常用菌株嗜热链球菌为出发菌株,反复使用高密度噬菌体培养处理,初步获得9株抗噬菌体突变株。对抗性菌株进行遗传稳定性、溶源性、EOP检测,及抗性菌株正常条件下发酵性能测定,综合各方面特性,筛选出遗传稳定,生长、发酵性能优于野生菌株的抗性菌株,对优于野生株的抗性菌株与敏感菌株一起在较高浓度噬菌体的环境中进一步发酵,测定其对噬菌体的抵抗能力、产酸能力、发酵后酸奶的黏度、硬度、乳清析出、口感及后酸化程度。结果表明:9株抗性菌株有6株遗传性比较稳定,其均为非溶源性菌,其中有3株生长能力、产酸能力、发酵乳黏度、硬度、接近于野生菌。这3株抗性菌株在高噬菌体浓度下发酵,有2株菌生长产酸正常,黏度、硬度、口感较好,凝乳时间较短、乳清析出较少并且后酸化程度相对较弱,适宜工业生产。Streptococcus thermophilus,one of the Yogurt fermentation strains,as the original strain commonly, using the high-density phage culture repeatedly,obtained 9 mutant strains of bacteriophage-resistant preliminary, determining their genetic stability,lysogeny, EOP and the yogurt fermentation properties under normal conditions, summing up all the characteristics. Select ones which was better than the wild-type strain in the genetic stability,growth and fermentation performance,and then fermentation with the better ones and the wild-type strain in higher concentrations phage environment further. Determination of phage resistance,viscosity,hardness, growth and acid of fermentation products ,also detect yogurt whey separation ,taste and after acidification. The result showed that 9 bacteriophage-resistants were all non-lysogenic bacteria and 6 of them had genetic stabilities,3 were close to the wild-type strain in growth ability,the ability to produce acid,fermented milk viscosity,hardness. Using the 3 mutants fermentation under higher concentrations phage environment,two bacteria growth normal ,and their acid production ,viscosity, hardness ,taste were all better than others ,shorter curd ,whey separation less and acidification relatively weak,they were suitable for industrial production,

关 键 词：嗜热链球菌 噬菌体 抗噬菌体突变株 自发突变 

分 类 号：TS201.3[轻工技术与工程—食品科学]