Production of bioactive peptides from soybean meal by solid state fermentation with lactic acid bacteria and protease

Abstract

In this study, soybean meal was first solid state fermented with different strains of Lactic Acid Bacteria (LAB). Among the strains used, Lactobacillus plantarum Lp6 was selected for further studies because of its highest Degree of Hydrolysis (DH) of protein (2.49±0.08%) in soybean meal after 72 h fermentation. Soybean meal fermented with L. plantarum Lp6 can also improve its DPPH radical scavenging and Angiotensin Converting Enzyme (ACE) inhibitory activities. The addition of protease into soybean meal during the fermentation resulted in lowered IC50 of DPPH radical scavenging and ACE inhibitory activities, indicating more bioactive peptides were produced during fermentation. Molecular weight distribution analysis revealed the Extracts from Fermented Soybean Meal (EFSM) was mainly composed of oligopeptides. These results indicated that soybean meal fermented with L. plantarum Lp6 and protease could be an easy and cheap method to produce functional food.