Zhikun Zeng,Hangyu Huang,Lin Wang,Yaqing Lin,Binbin Wang,Baodong Zheng,Yi Zhang,Lei Pan
Dictyophora indusiata is a nutritious edible mushroom, which polysaccharide exhibited a variety of biological activities. In this study, the digestion properties of steam-exploded Dictyophora indusiata polysaccharide (DIPS) were investigated by dynamic in vitro stomach-intestine digestive system. Here, the molecular weight of DIPS significantly was decreased and the microscopic surface structure appeared to be loose after 90 min of simulated stomach digestion. Interestingly, the molecular weight of DIPS was restored during the small intestine digestion phase, which was not significantly different compare with DIPS before stomach digestion, the functional groups, thermal stability and antioxidant properties of DIPS remained stable after digestion. It is remarkable that DIPS after dynamic in vitro stomach-intestine digestion regulated the composition of the gut microbiota, including Blautia , Megamonas , Parabacteroides and Phascolarctobacterium . In addition, DIPS promoted the level of acetic acid, propionic acid and butyric acid during the in vitro fermention, which were 2.42, 4.36 and 9.17 folds higher than controls, respectively. This study provides important significance for exploring the effects of edible mushroom polysaccharide on gut health.
Qin Yuan,Wen Liu,Wei Hao,Yi Chen,Yaqin Xiao,Hongyi Li,Mingju Shui,Ding-Tao Wu,Shengpeng Wang
Introduction Over decades, the source-function relationships of bioactive polysaccharides have been progressively investigated, however, it is still unclear how a defined structure may conduce to the bioactivities of polysaccharides. Objectives To explore the structure–function relationship of fungus polysaccharides, we employed a dextran sulfate sodium (DSS)‐induced colitis mouse model to compare the anti-inflammatory activity of two fungus polysaccharides from Dictyophora indusiata (DIP) and Tremella fuciformis (TFP), which exhibit distinct glycosidic linkages. Methods The structures of DIP and TFP were characterized through molecular weight detection, molecular morphology analysis, methylation analysis, and NMR analysis. Subsequently, we employed a DSS-induced colitis model to assess the anti-inflammatory efficacy of DIP and TFP. The colitis symptoms, histological morphology, intestinal inflammatory cytokines, and the composition and function of gut microbiota before and after polysaccharides treatment in colitis mice were also investigated. Results DIP, l,3-β-D-glucan with 1,4-β and 1,6-β-D-Glcp as branched chains, exhibited superior therapeutic effect than that of TFP consisted of a linear 1,3-α-D-mannose backbone with D-xylose and L-fucose in the side chains. Both DIP and TFP relieved DSS-induced colitis in a gut microbiota-dependent manner. Furthermore, metagenomics showed that DIP and TFP could partially reverse the bacterial function in colitis mice. Glycoside Hydrolase 1 (GH1) and GH3 were identified as being involved in hydrolyzing the glucose linkages in DIP, while GH92 and GH29 were predicted to be active in cleaving the α-1,3-linked mannose linkages and the glycosidic bonds of L-fucose residues in TFP. Conclusion Our findings highlight the pivotal role of glycosidic linkages in anti-inflammatory activities of fungus polysaccharides and would promote the design and discovery of polysaccharides with designated activity to be used as functional foods and/or therapeutics.
危险品化学品经营许可证（带存储）