Characterisation of Lactobacillus helveticus strains isolated from home-made dairy products in Iran

Abstract

The aims of this study were the isolation and characterisation of a number of lactobacilli strains from traditional dairy products. Fifteen home-made samples were pour-plated onto MRS and predominant colonies were randomly picked up. Nine isolated lactobacilli were grouped using rep-PCR fingerprinting, and partial sequencing of 16S-rRNA of group's representatives confirmed them as Lactobacillus helveticus. Detection of two CEP (prtH and prtH2) genes and examination of acidification and growth in milk revealed intradiversity among isolates. The findings indicate the possibility of isolating novel wild strains of L. helveticus from home-made products and emphasises on the necessity of both genetic and technological characterisation for deeper differentiation of strains.