Conversion of Phytochemicals by Lactobacilli: (Phospho)-β-glucosidases Are Specific for Glucosylated Phytochemicals Rather than Disaccharides.

Food-fermenting lactobacilli convert glycosylated phytochemicals to glycosyl hydrolases and thereby alter their biological activity. This study aimed to investigate the microbial transformation of β-glucosides of phytochemicals in comparison with utilization of cellobiose. Four homofermentative and four heterofermentative lactobacilli were selected to represent the metabolic diversity of . The genomes of , , , and encoded for 8 to 22 enzymes, predominantly phospho-β-glucosidases, with predicted activity on β-glucosides. and encoded for 3 β-glucosidases, for one, and for none. The hydrolysis of amygdalin, esculin, salicin, glucosides of quercetin and genistein, and ginsenosides demonstrated that several strains hydrolyzed β-glucosides of phytochemicals but not cellobiose. Taken together, several of the carbohydrate-active enzymes of food-fermenting lactobacilli are specific for glycosides of phytochemicals.