Spatiotemporal digestion and intestinal microbial fermentation properties of Ganoderma lucidum based on in vitro digestive system

Ganoderma lucidum (GL) is a renowned medicinal fungus. In this study, the structure of GL was characterized using ion chromatography and nuclear magnetic resonance spectroscopy. The degradation characteristics, gas production, and effects of GL granules on the gut microbiota were investigated during in vitro gastrointestinal digestion and colonic fermentation using a dynamic biomimetic gastrointestinal reactor. SEM and FTIR analyses showed remarkably structural changes, including indications of degradation and changes in the functional moiety of GL. GL increased the yields of short-chain and branched-chain fatty acids, particularly propionate, butyric acid, and valeric acid, while modulating the gas production profile during fermentation. It also improved the diversity of gut microorganisms, promoting the growth of beneficial bacteria Lactobacillus and inhibiting harmful Escherichia–Shigella species. These findings highlight the potential of GL as a prebiotic ingredient supporting gut health and provide new perspectives on the application of in vitro bionic digestive modeling.