MOLECULAR CHARACTERISATION AND IDENTIFICATION OF BACTERIA ISOLATED FROM KEFIR

Abstract

Kefir is a probiotic food composed mainly of lactic acid bacteria and yeasts; intake helps the proper function of the human intestine by increasing the beneficial flora. Depending on the geographic site, this product has distinctive organoleptic characteristics provided by the type of associated microorganisms and the quality of the milk used. Kefir has undergone industrialization, but to standardize the taste and quality, it is necessary to select the appropriate inoculum. Lactic acid bacteria isolated from artisanal kefir were identified and characterized molecularly. All the bacteria were rod shaped, Gram positive, catalase negative and with no sporulation; the bacteria also acidified the milk with different pH values. The
fermented milk showed viscous consistency, characteristic odor and most frequently it was gasified. Bacterial isolates were differentiated with RAPD and DAF-PCR, and classified into four groups. The sequences of the 16S gene identified them as Lactobacillus kefiri.