International Journal of Fermented Foods

This study presents, antimicrobial activity of bioactive peptides derived from fermentation of soy milk along with their production by Lactobacillus plantarum C2 strain. Bioactive peptides are specific fragment of protein, can be released by fermentation, upon release they may act as antimicrobial, antioxidant, antihypertensive, immunomodulatory and hypocholesterolemic activities. LP C2 showed very good growth in soy milk by increasing their count and acidity significantly, consequently pH dropped. Ultrafiltration was used for the separation of peptides and their peptide contents analyzed by OPA assay. 10kDa fraction was found high in peptide (655.128±2.95 μg/ml). Antimicrobial activity of bioactive peptide fractions was checked by agar well diffusion method and found that 5 kDa showed highest activity against all the pathogens with highest inhibition against E.coli (12±0.57) followed by S. dysenteriae (11±0.57), L. monocytogenous (10±0.57) and B. cereus (10±0.57 mm). However it was observed that unfractionated sample high in antimicrobial activity, may be due to combined effect of all the fractions.