四川泡菜中植物乳杆菌的筛选与鉴定

Isolation and Identification of Lactobacillus plantarum in Sichuan Paocai

摘要:

该研究旨在从四川泡菜中筛选植物乳杆菌，为益生菌筛选提供来源。经MRS琼脂培养基筛选，采用革兰氏染色法，生化鉴定法，结合分子生物学方法，对筛选的菌株进行鉴定。VITEK 2棒状杆菌鉴定卡（CBC）共涉及到41个生化反应，能够鉴定到种属水平，该方法能够很好的筛选植物乳杆菌。经CBC卡鉴定，20个菌株中筛选到12个菌株，可鉴定为植物乳杆菌。这些菌株经16S rRNA PCR扩增测序后，在NCBI网站上进行同源性比对，确定为植物乳杆菌。由邻接法构建的系统进化树可知，该12个菌株与已知植物乳杆菌序列聚为一簇，6号菌株与Lactobacillus plantarum 3356聚为一支，亲缘关系更近；4号、5号、14号、15号、23号和38号菌株与Lactobacillus plantarum NCU116，Lactobacillus plantarum MBEL2169，Lactobacillus plantarum AN7等序列相似性极高，无遗传距离。综合所有的鉴定结果，这12个菌株都被鉴定为植物乳杆菌。CBC鉴定卡是初筛植物乳杆菌较好的方法。

Abstract:

Lactobacillus plantarum were isolated from Sichuan Paocai and screened for probiotics. The strains were separated using MRS agar medium, and then identified using Gram staining, biochemical identification, and molecular biology methods. The VITEK 2 Corynebacterium identification card (CBC) includes a total of 41 biochemical reactions and enables identification to the species level. Of the 20 strains of bacteria detected, 12 strains were identified as L. plantarum using the CBC cards. These strains were subjected to16S rRNA PCR amplification and sequencing, followed by homologous sequence alignment on the NCBI website. The phylogenetic tree constructed by the neighbor-joining method showed that all 12 strains were clustered with known L. plantarum sequences. Strain No. 6 was clustered with L. plantarum 3356. Strain numbers 4, 5, 14, 15, 23, and 38 had very high sequence similarity with L. plantarum NCU116, L. plantarum MBEL2169, and L. plantarum AN7, with no genetic distance. In conclusion, all 12 strains were identified as L. plantarum. CBC identification cards are an effective method for the identification of L. plantarum.