European Journal of Biomedical and Pharmaceutical Sciences

ISOLATION, CHARACTERIZATION AND DECARBOXYLASE ACTIVITYOF LACTIC ACID BACTERIA ISOLATED FROM DAIRY PRODUCTS

Sayani Chatterjee and Archana Vaishnana*

ABSTRACT

The relationship between certain food and health benefits has been investigated for many years. In recent years, there has been a lot of active research in the field of probiotics, due to the growing commercial interest in the probiotic food. Strains of Lactobacillus were introduced into dairy products because of the potential advantage of consuming active LAB adapted to the intestine and to produce mildly acidified yoghurts. In the study isolated bacteria were observed by light microscope. It is clear that the bacteria were gram positive, rod shaped bacilli and spherical shaped coccus occurring singly or in chains. The gram staining results indicated that the isolated bacteria could be identified as lactobacilli. In performing catalase test, the isolated bacterium is catalase negative. It is well known that Lactobacillus is catalase negative. Isolated LAB strains were tested for different amino acid decarboxylase activities. BA production was not detected in the Decarboxylase tests carried out by the isolated LAB. In performing catalase test, no bubble was observed indicating that the isolated bacterium is catalase negative and could not mediate the decomposition of H2O2 to produce O2. It is well known that Lactobacillus is catalase negative. Decarboxylation systems consist of a decarboxylase and a precursor. Their combined action results in amino acid intake, decarboxylation, and release of the corresponding BA. BA production was not detected in the Decarboxylase tests carried out by the isolated LAB.

Keywords: Lactic Acid Bacteria, Biogenic amines, Catalase, Oxidase, Decarboxylase activity and Dairy products.