Isolation and identification of lactic acid bacteria from environmental samples

Abstract

Isolation of lactic acid bacteria (LAB) is the first and crucial step to study possible roles of LAB in the environment, especially in food fermentation. This is also important to use the organisms for further application. LAB are diverse bacterial group and have diverse growth characteristics. Culture condition of LAB is thus varied, and selection of a suitable culture medium is essential for the purposes. Identification is also an important step, since certain desirable and undesirable characteristics are shared within species. Identification was classically carried out by phenotypic characteristics but is usually performed by DNA sequence-based approaches. 16S rRNA gene sequencing is generally used for identification, and sequencing of housekeeping genes is used when needed. In addition, identification based on whole-genome sequence similarities is becoming common. Here we describe isolation and identification of LAB briefly.