Growth and bioactive peptides production potential of Lactobacillus plantarum strain C2 in soy milk: A LC-MS/MS based revelation for peptides biofunctionality

Bioactive peptides are protein fragments which have a positive impact on the functions and conditions of living organisms. Apart from other animal and plant sources soybean is an excellent source of bioactive peptides. In recent years, fermentation has been explored as effective way for bioactive peptides generation. Hence, the present study has been carried out to evaluate an indigenous Lactobacillus plantarum strain C2 (LP C2) for fermentation and peptides generation in soy milk. Peptides were further tested for important biofunctionalities (antioxidative and antihypertensive) and characterized by LC-MS/MS. Besides its excellent log count increases, protein hydrolysis and a galactosidase activities, LP C2 reduced soy oligosaccharides (sucrose, raffinose and stachyose) in a strain specific manner. Following fractionation, the 10 kDa fraction not only showed the highest peptide content in comparison to 3 kDa and 5 kDa, but also exhibited the highest antioxidant activity. Conversely, no significant differences were observed in ACE-inhibitory activities of all three fractions of peptides. Moreover, we are the first to report L plantarum mediated generation, and LC-MS/MS based characterization of 17 biofunctional soy peptides showing both antioxidant and ACE-inhibitory activities. Thus, this strain can be further used for the preparation of soy based functional fermented foods and bioactive food supplements. (C) 2017 Elsevier Ltd. All rights reserved.