Role of Lactic Acid Bacteria Phospho-β-Glucosidases during the Fermentation of Cereal by-Products

• Published in: Foods Vol. 10; no. 1; p. 97
• Main Authors: Acin-Albiac, Marta, Filannino, Pasquale, Arora, Kashika, Da Ros, Alessio, Gobbetti, Marco, Di Cagno, Raffaella
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 05.01.2021; MDPI
• Subjects: Aglycones; Bacteria; Biodegradation; Bioprocessing; brewers’ spent grain; By products; Byproducts; Carbohydrates; Cellobiase; Cellobiose; cereal by-products; Chromatography; Enzymatic activity; Fermentation; Fermented food; Food; Food plants; Food production; Food science; Gene expression; Genomes; Gentiobiose; Glucosidase; Glucosides; Lactic acid; Lactic acid bacteria; lactic acid bacteria metabolism; Lignin; Lignocellulose; Mass spectrometry; Metabolism; Metabolites; Phenolic compounds; Phenols; phospho-beta-glucosidases; Plant-based foods; Plants; Potassium; Redundancy; Scientific imaging; β-Glucosidase; United States > US; Ireland; Germany; India; lactic acid bacteria metabolism; cereal by-products; phospho-beta-glucosidases; brewers’ spent grain
• ISSN: 2304-8158; 2304-8158
• DOI: 10.3390/foods10010097

Bioprocessing using lactic acid bacteria (LAB) is a powerful means to exploit plant-derived by-products as a food ingredient. LAB have the capability to metabolize a large variety of carbohydrates, but such metabolism only relies on few metabolic routes, conferring on them a high fermentation potential. One example of these pathways is that involving phospho-β-glucosidase genes, which are present in high redundancy within LAB genomes. This enzymatic activity undertakes an ambivalent role during fermentation of plant-based foods related to the release of a wide range of phenolic compounds, from their β-D-glycosylated precursors and the degradation of β-glucopyranosyl derived carbohydrates. We proposed a novel phenomic approach to characterize the metabolism drift of and caused by a lignocellulosic by-product, such as the brewers' spent grain (BSG), in contrast to Rich De Man, Rogosa and Sharpe (MRS) broth. We observed an increased metabolic activity for gentiobiose, cellobiose and β-glucoside conjugates of phenolic compounds during BSG fermentation. Gene expression analysis confirmed the importance of cellobiose metabolism while a release of lignin-derived aglycones was found during BSG fermentation. We provided a comprehensive view of the important role exerted by LAB 6-phospho-β-glucosidases as well the major metabolic routes undertaken during plant-based fermentations. Further challenges will consider a controlled characterization of gene expression correlated to the metabolism of β-glucosides with different aglycone moieties.