Biochemical and Molecular Characterization of Lactic Acid Bacteria (LAB) Isolated from Fermented Pulses

Pulses are excellent source of protein, fiber and other key nutrients. Fermented pulse-based products are routinely used in many parts of India. In this study, an attempt has been made to isolate potent probiotic lactic acid bacteria from traditionally fermented Vigna radiata (mung beans) and Cajanus cajan (pigeon pea). Fermented seed samples of both the pulses were used for the isolation of lactic acid bacteria using Lactobacilli selection medium de Man, Rogosa and Sharpe. Twenty colonies were randomly selected, based on differential colony morphology. Only Gram-positive and catalase-negative isolates were further propagated for biochemical characterization. The isolates obtained showed different growth patterns at acidic conditions (pH 2, 3 and 4) and at high bile salt concentration (0.5% and 1.0%). Most of the isolates showed promising results in antibiotic resistance assay and cell surface hydrophobicity test. Three potent isolates were identified as Pediococcus pentosaceus (RBS1), Enterococcus durans (RBS3) and Pediococcus pentosaceus (RBS10) using 16S rDNA sequencing.