Comparative effects of different enzymatic hydrolysates of konjac glucomannan on gut flora and constipation in rats

This study aimed to compare the effects of different hydrolysates (named GKOS and MKOS) on constipated rats, which were obtained by degradation from konjac glucomannan by β-glucanase and β-mannanase, respectively. GKOS and MKOS were characterized and administered by gavage at 100 mg kg^-1 to constipated rats. The variation of the gut flora, content of short-chain fatty acids (SCFAs), defecation function, gastrointestinal motility, and intestinal mucus secretion were determined to evaluate their regulatory effects on constipation. The results revealed the more prominent augmentation of species richness in MKOS than with GKOS. They also possessed diverse modulatory effects on different genera, such as Prevotella and Parabacteroides. Unexpectedly, there was no statistical divergence between GKOS and MKOS in defecation parameters, gastrointestinal transit, serum parameters, and mucous secretion. Overall, MKOS and GKOS exhibited differential regulatory function on gut microbiota in vivo, but with nearly consistent therapeutic effects on constipation.