The V-Type Lotus Seed Starch-Egcg Complex Regulates the Production of Butyric Acid by Regulating Intestinal Microbiota

Abstract

Starch and polyphenols are currently common food components that can form starch-polyphenol complexes with V-type crystalline structures under certain conditions. They are classified as the fifth type of resistant starch (RS5). However, research on the impact of starch-polyphenol complexes on gut microbiota is insufficient. In this study, the lotus seed starch-EGCG complex (LSE) was prepared by heating. The structural changes of LSE during fermentation and its impact on gut microbiota were investigated through an in vitro simulated large intestine fermentation model. The results show that LSE can be prepared by heating for 20 minutes at 100°C, resulting in a V-type crystalline structure. After fermentation, the LSE still maintained the V-type crystalline structure, while the amorphous part of the LSE were decreased. LSE fermentation  promoted the relative abundance of probiotics such as Faecalibaculum and Bifidobacterium, and showed good potential to promote butyric acid production. Correlation analysis revealed that the correlation between the structural characteristics of LSE and the microbial community undergo changes. Acetic acid and butyric acid consistently show a positive correlation with the relative crystallinity, order degree and double helix degree of the LSE. These findings can provide basic data for the application of starch-polyphenol complexes in the food industry.

Keywords: V-type inclusion complex, in vitro fermentation, intestinal microbiota, short-chain fatty acids