Preparation, structural characterisation, and antioxidant activities of polysaccharides from eight boletes (Boletales) in tropical China

Purification and Structure Characterization of the Crude Polysaccharide from the Fruiting Bodies of Butyriboletus pseudospeciosus and Its Modulation Effects on Gut Microbiota

“…The 1 H-NMR spectrum of BPP is shown in Figure S2A . Previous reports have reported that the crowded and narrow regions in the range of 3.0–5.5 were typical signals of polysaccharides [ 7 , 20 ], which are in line with our spectrum. As shown in Figure S2A , the anomeric hydrogen signals at 5.11 and 4.93 can be observed, respectively.…”

“…The contents of carbohydrates, protein, and uronic acid in BPP were 64.00%, 1.95%, and 1.19%, respectively ( Table 1 ). The HPLC detection suggested that glucose (Glc), mannose (Man), and galactose (Gal) were the most abundant components in the compositions of BPP ( Figure 1 A), which is in line with the previous studies [ 7 ]. The results manifest that the polysaccharides from the fungi of the family Boletaceae could be composed of Glc, Man, and Gal mostly.…”

“…Then, the anomeric hydrogen signals lower than 5 ppm corresponded to the β -pyranose unit mostly, while greater than 5 ppm corresponded to the α -pyranose unit [ 17 , 21 ], which suggests that BPP contains both α -pyranose and β -pyranose sugar units. The resulting spectrum is consistent with previous studies relating to the polysaccharides from the species of Boletaceae [ 7 ].…”

“…BPP shared a strong absorption peak at 3412 cm −1 and a weak absorption peak at 2912 cm −1 , which were assigned to the stretching peaks of O-H and C-H, respectively ( Figure 1 B). The intense absorption peak approximately at 1635 cm −1 could arise from the carbonyl group of the polysaccharide [ 7 ]. The absorption peak detected at 1413 cm −1 was due to the C-H variable angle vibration.…”

“…In China, some species of Boletaceae were treated as medicinal fungi in “South Yunnan Medica”, and their efficacies included expelling pathogenic heat, enriching weakness, refreshing the brain, and improving blood circulation. Pharmacological studies have revealed that Boletaceae has antidiabetic, anticancer, immunoregulatory, and antioxidative activities [ 5 , 6 , 7 ]. Currently, the species of Boletaceae are regarded as promising functional food, and they have underwent an increasing number of investigations due to their delicious taste and versatile nutrients [ 8 ].…”