Effects of in vitro simulated digestion and fecal fermentation of polysaccharides from straw mushroom (Volvariella volvacea) on its physicochemical properties and human gut microbiota

Int J Biol Macromol. 2023 Jun 1:239:124188. doi: 10.1016/j.ijbiomac.2023.124188. Epub 2023 Mar 28.

Abstract

Herein, the fermentation and digestion behavior of Volvariella volvacea polysaccharide (VVP) were examined through the in vitro simulation experiment. The results revealed that succeeding the simulated salivary gastrointestinal digestion, the molecular weight of VVP was reduced by only 8.9 %. In addition, the reducing sugar, uronic acid, monosaccharide composition and Fourier transform infrared spectroscopy characteristics of VVP did not change significantly, which indicate that saliva-gastrointestinal could not digest VVP. However, 48 h of fecal fermentation of VVP dramatically reduced its molecular weight by 40.4 %. Furthermore, the molar ratios of the monosaccharide composition altered considerably due to the degradation of VVP by microorganisms and the metabolysis into different short-chain fatty acids (SCFAs). Meanwhile, the VVP also raised the proportion of Bacteroidetes to Firmicutes and promoted the proliferation of some beneficial bacteria including Bacteroides and Phascolarctobacterium, whereas it inhibited the growth of unfavorable bacteria such as Escherichia-shigella. Therefore, VVP has the potential to have a positive influence on health and hinder diseases by improving the intestinal microbial environment. These findings provide a theoretical foundation to further develop Volvariella volvacea as a healthy functional food.

Keywords: Fecal fermentation; Gut microbiota; In vitro digestion; Short-chain fatty acids; Volvariella volvacea polysaccharide.

MeSH terms

  • Agaricales* / metabolism
  • Digestion
  • Fatty Acids, Volatile / metabolism
  • Fermentation
  • Gastrointestinal Microbiome*
  • Humans
  • Polysaccharides / metabolism
  • Polysaccharides / pharmacology

Substances

  • Polysaccharides
  • Fatty Acids, Volatile

Supplementary concepts

  • Volvariella volvacea