Solid–state fermentation of germinated black bean (Rhynchosia nulubilis) using Lactobacillus pentosus SC65 and its immunostimulatory effect

Abstract Germinated black bean ( Rhynchosia nulubilis ) (GRN) has several beneficial health effects, including immunostimulation. To enhance the immunostimulatory effect of GRN, it was fermented with lactic acid bacteria (LAB). A total of 57 strains of LAB that showed good growth on GRN were isolated from various fermented foods and vegetables. Among them, Lactobacillus pentosus SC65 was selected as a starter culture for GRN fermentation. Optimum solid–state fermentation conditions of GRN with L . pentosus SC65 (GRN–SC65) were: water content of 40% (v/w), fermentation time of 24 h, fermentation temperature of 30 °C, and inoculation volume of 5% (v/w). RAW264.7 cells treated with hot water extract of GRN–SC65 showed high nitric oxide production and phagocytic activity, indicating high immunostimulatory activity of GRN–SC65.