Protective effects of konjac glucomannan on gut microbiome with antibiotic perturbation in mice

This study assessed the protective effects of konjac glucomannan (KGM) on gut microbiome against the antibiotic perturbation in C57BL/6J mice. The native KGM (1.82 × 10 7 ) was partially hydrolyzed by endo-1,4-β-mannanase, and two hydrolyzed fractions (KGM-eM with 3.82 × 10 5  Da and KGM-eL with 8.27 × 10 3  Da) were characterized and applied to mice with perturbation of antibiotics in comparison with the native KGM. The results showed that the native KGM better maintained the microbial diversity and composition in feces, and increased the production of the individual and total SCFAs in feces and serum with perturbation of antibiotics. In contrast, KGM with lower MW (KGM-eM and KGM-eL) increased the proportion of Lactobacillus and SCFA production with no antibiotics, however, the prebiotic effects were eliminated with perturbation of antibiotics. These results have demonstrated the protective effects of KGM with high MW on gut microbiome against the antibiotic perturbation in vivo.