Different concentrations of grape seed extract affect in vitro starch fermentation by porcine small and large intestinal inocula.

摘要

BACKGROUND: Grape seed extract (GSE) phenolics have potential health-promoting properties, either from compounds present within the extract, or metabolites resulting from gastrointestinal tract (GIT) fermentation of these compounds. This study describes how GSE affected the kinetics and end-products of starch fermentation in vitro using pig intestinal and fecal inocula. Six GSE concentrations (0, 60, 125, 250, 500, and 750 micro g ml-1) were fermented in vitro by porcine ileal and fecal microbiota using starch as the energy source. Cumulative gas production, and end-point short chain fatty acids and ammonia were measured. RESULTS: GSE phenolics altered the pattern (gas kinetics, and end-products such as SCFA and NH₄+) of starch fermentation by both inocula, at concentrations above 250 micro g ml-1. Below this level, neither inoculum showed any significant (P>0.05) effect of the GSE. CONCLUSION: The results show that GSE phenolics at a concentration over 250 micro g ml-1 can have measurable effects on microbial activity in an in vitro fermentation system, as evidenced by the changes in kinetics and end-products from starch fermentation. This suggests that fermentation patterns could be conceivably shifted in the actual GIT, though further evidence will be required from in vivo studies.