Exploring the mechanism of probiotics in enhancing the utilization of chemical components (or polyphenols) of grape seed extract

Fecal samples from 20 healthy adults were collected for in vitro fermentation experiments to investigate the effects of combined probiotics on the utilization of grape seed extract in humans. After fermenting for 24 h, short-chain fatty acids, metabolites, and gut microbiota composition were analyzed. Short-chain fatty acids in the grape seed extract probiotics group were significantly higher than those in the grape seed extract group. Probiotics significantly enhanced the conversion and utilization of catechins and epicatechins in grape seed extract group and increased the production of 3-hydroxyphenylacetic acid. The 16S rRNA sequencing results revealed that compound probiotics significantly increased the relative abundance of Lacticaseibacillus, HT002, Bifidobacterium, and Lactobacillus and reduced that of Escherichia-Shigella. Our findings showed considerable individual variability in the metabolic utilization of grape seed extract in humans. The consumption of probiotics appears to significantly enhance the utilization.