新疆赛里木酸奶源降胆固醇植物乳杆菌的筛选鉴定及其安全性研究

Screening,identification and safety of cholesterol-lowering Lactobacillus plantarum from Sayram Ketteki in Xinjiang

长期血清胆固醇水平升高被认为是心血管疾病的主要危险因素。新疆阿克苏地区拜城县医疗水平落后,地理环境恶劣,却被认定为世界级“长寿乡”,当地人们习惯食用家庭自制的赛里木酸奶,其被誉为“长寿秘诀”。但是目前对赛里木酸奶的研究较少,还未见有对赛里木酸奶源降胆固醇微生物的报道。该研究以从赛里木酸奶中分离筛选出的具有优良基础特性的8株疑似植物乳杆菌为样品,研究了其降胆解固醇的能力,并对高降解胆固醇菌株通过生理生化试验进一步进行了鉴定,最后通过抗生素敏感性、是否含质粒、是否产生物胺和溶血活性试验对高降解胆固醇菌株的安全性进行了初步研究。筛选出3株高降解胆固醇菌株:R2-5、R2-7和R4-2,其对胆固醇的降解力分别是48.19%、48.92%和48.50%。经鉴定确定均为植物乳杆菌,并且3株菌对部分抗生素具有抗性,但不含有质粒,不产生物胺,无溶血活性,即具有一定的安全性。该研究为下一步对菌株进行体内降胆固醇功能研究和应用提供数据支撑,对赛里木酸奶的推广具有重大意义,为开发具有我国自主知识产权的原创性益生菌提供了新资源。

Chronically elevated serum cholesterol levels are considered to be a major risk factor for cardiovascular disease.In Baicheng County,Aksu Prefecture,Xinjiang,the medical level is backward and the geographical environment is harsh,but it is recognized as a world-class‘longevity township’.Local people are accustomed to eating home-made Sayram Ketteki(a yogurt-like fermented dairy product),which is known as the‘longevity secret’.However,there are few studies on Sayram Ketteki at present,and there are no reports on cholesterol-lowering microorganisms from Sayram Ketteki.In this study,eight strains of suspected Lactobacillus plantarum with excellent basic characteristics isolated and screened from Sayram Ketteki were used as samples to study their cholesterol-lowering ability,and the strains with high cholesterol degradation were further identified through physiological and biochemical tests.Finally,the safety of the high cholesterol-degrading strains was preliminarily studied by antibiotic sensitivity,plasmid,biogenic amines and hemolytic activity tests.As a result,three strains of high cholesterol degradation were screened out:R2-5,R2-7,and R4-2,with the ability of cholesterol degradation of 48.19%,48.92%,and 48.50%,respectively.After identification,all strains were confirmed to be L.plantarum,and the three strains were resistant to some antibiotics,but did not contain plasmids,did not produce amines,and had no hemolytic activity,so they had certain safety.This study provides data support for the further research and application of the cholesterol lowering function of the strains in vivo,which is of great significance for the promotion of Sayram Ketteki,and provides new resources for the development of original probiotics with independent intellectual property rights in China.