Exploring Morchella esculenta polysaccharide extracts: In vitro digestion, fermentation characteristics, and prebiotic potential for modulating gut microbiota and function

Abstract

Morchella esculenta, a nutritious and medicinal edible mushroom, has gained an increasing attention due to the bioactive properties of its polysaccharides. This study employed in vitro simulated human digestion and fecal fermentation models to evaluate the effects of M. esculenta polysaccharide on gut microbiota composition and short-chain fatty acids (SCFAs) production. Additionally, a relationship between M. esculenta polysaccharide composition, gut microbiota, and functional role was constructed to elucidate their interactions. The results revealed that 44.87 % of M. esculenta polysaccharide was digested, leading to a reduction in molecular weight and alterations in monosaccharide composition, including decreased glucose and increased galactose and mannose. Fermentation of M. esculenta polysaccharide significantly enhanced SCFAs production and promoted the growth of beneficial gut bacteria, such as Bacteroides, Collinsella, and Bifidobacterium, while notably reducing Ruminococcus torques. Carbohydrate metabolism was enriched in Collinsella and Bifidobacterium which positively correlated with SCFAs biosynthesis e.g., propanoate and butanoate biosynthesis. These findings provide valuable insights into M. esculenta polysaccharide as prebiotic potential, highlighting its functional role in modulating gut microbiota and promoting gut health.

Keywords: Dietary polysaccharide; Gut microbiota; Morchella esculenta; Mushroom; Short-chain fatty acids.