乳杆菌和双歧杆菌的生理代谢多样性研究

Physiological and metabolic diversity of Lactobacillus and Bifidobacterium strains

比较了拥有潜在益生特性的28株乳杆菌(Lactobacillus)和26株双歧杆菌(Bifidobacterium)的生理代谢差异,这些菌株多数来源于波兰。筛选过程当中,首要的指标是检测菌株对低pH值和对胆盐的抗性以及在发酵或非发酵乳制品当中的存活能力。考察了这些候选菌株是否产生某种拮抗物质,同时评价这些物质对来自于食物或肠道内的病原微生物或生产当中不渴望微生物的抑制效果。研究了混合发酵剂中各菌株之间的共生能力,并对它们在生产加工过程中表现出的对诸如冷冻、冻干或储藏等处理的耐受能力进行评价。采用高效液相色谱(HPLC)的方法对菌株利用各种碳源所生成的代谢产物的类型进行了测试。结果表明,所有供试菌株存在很大的生理代谢差异,因而,应选择那些具有科学测定基础的菌株作为益生菌菌株。

The lecture will focus on some physiological and metabolic diversity of 28 Lactobacillus and 26 Bifidobacterium strains. Most of them were Polish origin and they were compared with some current probiotic strains. The first requirement we set for a candidate Lactobacillus and Bifidobacterium strains were resistance to low pH, resistance to bile and ability to survive in fermented and non fermented milks. With our collection of candidate strains we also tested for production of an antimicrobial substances that were active against pathogens isolated from food and intestine and against technically undiserable microorganisms. We also put some efforts to check the possibility of coexistence the tested strains in mixed starters and resistance to production processing, i.e. freezing, lyophilisation, storage.Using HPLC methods we also estimated end products of sugar catabolism. As a result of experiments we stated a great diversity among the tested strains and selected some of them that meet the requirements for a scientifically based probiotic strains.