Effects of Different Hemicellulose Components on Fermentation Kinetics and Microbial Composition in Fecal Inoculum from Suckling Piglets In Vitro

Abstract

This study investigated the fermentation characteristics of different hemicellulose components using a fecal inoculum derived from suckling piglets. The results showed that after 60 h of fermentation, the arabinogalactan (Ara-gal), glucomannan (Glu-man), galactomannan (Gal-man), and mannan (Man) groups exhibited similar levels of gas production, which were higher than those of the β-glucan (β-Glu) group. The β-Glu group had the lowest pH value. After 48 h of fermentation, the Ara-gal group had the highest microbial crude protein content and the lowest ammonia nitrogen content. The Glu-man, Gal-man, and Man groups produced similar amounts of acetate, propionate, and total short-chain fatty acids (SCFAs), which were higher than those in the Ara-gal and β-Glu groups. Furthermore, the Man and Ara-gal groups showed the highest butyrate production. Significant differences in the microbial community composition were observed among the groups. Correlation analyses further revealed that the abundance of specific bacteria, such as Prevotella_9 and Parabacteroides, was closely related to the production of acetate, propionate, and butyrate. These results suggest that Glu-man, Gal-man, and Man undergo rapid fermentation, with Ara-gal following, while β-Glu ferments the slowest. The distinct fiber compositions and fermentation properties of different hemicellulose components significantly influence the microbial composition and SCFA production. Our findings offer valuable theoretical insights for selecting fiber components in the diets of suckling piglets and potentially in infants.