The positive correlation of antioxidant activity and prebiotic effect about oat phenolic compounds.

The correlation of antioxidant activity and prebiotic effect about oat phenolic compounds was invested, while there exists limited studies. Free and bound phenolic compounds were separated from ethyl acetate, n-butanol and aqueous fractions. Fluorescence in situ hybridization was used to investigate gut microbiota of in vitro fermentation samples. The results showed that ethyl acetate fraction possesses higher total phenolics contents than that of aqueous fraction (p < 0.01). The bound-n-butanol and free-ethyl acetate fraction exhibited the higher antioxidant capacity (p < 0.01). The phenolic compounds with more powerful antioxidant capacity could promote the proliferation of gut microbiota (Lactobacillus/Enterococcus spp. and Bifidobacterium spp.) (p < 0.05) and inhibit the growth of gut microbiota (Bacteroides spp. and Clostridium/histolyticum group). There is a positive correlation of antioxidant activity and prebiotic effect about oat phenolic compounds. This study provides a basis for the correlation between antioxidant stress and gut microbiota regulation in vivo.