侗族传统酸肉与腌鱼中降胆固醇乳酸菌的筛选与鉴定

Screening and identification of cholesterol-lowering lactic acid bacteria from Dong minority traditional fermented sour fish and meat

以侗族传统酸肉、腌鱼作为乳酸菌筛选源,分离出23株乳酸菌。采用邻苯二甲醛法筛选出2株体外降胆固醇能力较强的乳酸菌YRA7和YRB4。经形态学观察、理化指标鉴定及16S r DNA分子生物学鉴定,确定2株菌分别为植物乳杆菌(YRA7)和消化乳杆菌(YRB4)。两者均呈现出较好的耐酸、耐盐和耐胆盐特性,在p H3.0以及含6%Na Cl的培养基中可以生长,在含0.3%胆盐的MRS培养基中存活率分别为75.68%(YRA7)和61.37%(YRB4)。此外,两者均具有较好的生长性能与产酸性能,可以作为降胆固醇的潜在益生菌。

23 strains of lactic acid bacteria were isolated from Dong minority traditional fermented sour fish and meat. YRA7 and YRB4 which have the good cholesterol reducing effect were screened by O-phthalaldehyde. Through the morphological observation, physicalandchemical identification and 16 S r DNA molecular analysis, YRA7 strain was identified as L. plantarum, and YRB4 strain was identified as L. alimentarius. Bothstrain showed high acid resistance and bile salt tolerance. They could grow in p H 3.0 MRS broth and the MRS broth contained 6% Na Cl, and the 0.3% bile salt, survival rate was 75.68%（YRA7） and 61.37%（YRB4） respectively. Additionally, they also had good growth characteristics, acid-producing ability, so they could be as the potential probiotics with cholesterol-lowering activity.