Search

A crude polysaccharide derived from Flammulina velutipes (FVP), mainly consisting of glucose linked with β-glycosidic bonds, was administered to 6 week-old male ICR mice by gavage for five weeks, to investigate the effects on mice intestinal microbiota and immune response. The pH of the intestinal compartments decreased while short chain fatty acids concentrations increased in FVP-fed groups, in a dose dependent manner. High throughput sequencing revealed the enrichment in the diversity and an alteration in the composition of the fecal microbiota in the FVP fed mice. A significant decrease in the Firmicutes/Bacteroidetes ratio, relative abundances of Lactobacillus and Akkermansia were related to the energy absorption. The relative abundances of Porphyromonadaceae and Bacteroidaceae positively correlated with an increase in serum immunoglobulin and cytokines. This study indicated that this crude polysaccharide from F. velutipes could modulate the gut microbiota and represented a potential capacity of obesity suppression and immune regulation.

Various traditional edible fungi were demonstrated to modulate gut microbiota. In this study, 1H NMR and high-throughput sequencing were used to investigate the difference of microecology modulating function between Ophicordyceps sinensis and Cordyceps militaris. The data showed that total 7 constituents (glucose, mannitol, trehalose, aspartate, glutamate, lysine, threonine) were selected as potential biomarkers to identify O. sinensis and C. militaris based on 1H NMR. After in vitro fermentation, both O. sinensis and C. militaris modulated gut microbiota composition, via decreasing the ratio of Firmicutes to Bacteroidetes. However, O. sinensis could significantly decreased the pH and stimulated the production of short-chain fatty acids versus C. militaris. O. sinensis also increased the relative abundance of probiotics including Phascolarctobacterium and Bifidobacterium. In general, the results suggested that O. sinensis had more positive effects on gut microbiota compared with C. militaris, which was conducive to the development of functional products of traditional edible fungi.

Excessive exercise-induced fatigue has become a serious health issue and can cause gut dysbiosis. Tuber indicum (T. indicum) polysaccharide can act as prebiotics to regulate gut microbiota and this effect may play an important role in relieving fatigue. Therefore, T. indicum polysaccharide was prepared and mainly consisted of glucose linked with β-glycosidic bonds. Based on a mouse model of exhaustive swimming-induced fatigue, such polysaccharide decreased blood lactic acid content and increased ATPase activity of fatigue mice, which was accompanied by improved short chain fatty acids concentration and gut integrity. Additionally, T. indicum polysaccharide ameliorated gut dysbiosis by decreasing the ratio of Firmicutes to Bacteroidetes and increasing Bacteroides in fatigue mice. Spearman's correlation analysis suggested that T. indicum polysaccharide-modulated microbiota was significantly correlated with its anti-fatigue effect. These findings suggested the potential of T. indicum polysaccharide as prebiotics, to protect mice against excessive exercise-induced fatigue by regulating gut microbiota.

Flammulina velutipes has been reported to be beneficial in learning and memory capabilities, but the mechanisms underlying this remain unclear. In this study, Morris water maze and biochemical analyses of rat brain were used to evaluate the effects of F. velutipes polysaccharides (FVP) on scopolamine-induced learning and memory impairments. Results suggested that FVP significantly decreased the escape latency and total swimming distance of rats in the hidden platform test and increased the numbers of platform crossing and swimming distance of rats in the probe test. Biochemical examinations revealed that FVP significantly elevates SOD and GSH-Px activities, as well as neurotransmitter levels. The increased acetylcholine content owed to the increased acetylcholine acetyltransferase activity and decreased acetylcholinesterase activity. Moreover, learning and memory associated signalling pathways were activated by FVP elevating the expression of connexin 36 and p-CaMK II. These results conclusively proved that FVP is a potent agent against the progression of cognitive impairment.