Genotypic and phenotypic study of Lactobacillus species isolated from traditional yogurt and cheese in southwest Iran

摘要

Lactic acid bacteria (LAB) have the property of producing lactic acid from sugars by a process called fermentation. These bacteria are broadly used in the production of fermented food products, such as yogurt, cheeses, sauerkraut and sausage. Among them Lactobacillus species are use d industrially for the production of yogurt and cheese . The purpose of present study was to identify the genotypic and phenotypic of Lactobacillus species in the traditional cheeses and yogurt produced in the Chaharmahal Va Bakhtiari province located in southwest Iran using molecular technique. 18 Dalameh cheeses and 15 traditional yogurt specimens were collected from various groceries and markets in the Cha harmahal Va Bakhtiari province. Genomic DNA was extracted from yogurt and cheese samples, as well as reference strains and PCR reaction was down for amplif ication of 16S rDNA gene. PCR products were digested by Taq I and Hae III restriction enzymes and fragments were analyzed in 2% agarose gel electrophoresis. The results of present study showed that Lactobacillus delbrueckii ( Lb. delbrueckii ), Lb. acidophilus , Lb. brevis and Lb. lactis strains from traditional cheese and yogurt is important and more frequent in dairy industry. These findings could be used as starter cultures in manufacturing of cheeses and yogurt to approach better and safety dairy products with high quality.