Flammulina velutipes, (Curt. ex Fr.) Sing, a popularly edible fungus, has been widely used both as a restorative drug and a tonic food in China. In the current study, the effect of F. velutipes polysaccharides was evaluated with a constipated rat model induced by loperamide hydrochloride. The rats were divided into six groups: normal group, model group, positive control group, F. velutipes polysaccharides high, moderate and low dose groups. Rats were given 2 mL of Loperamide hydrochloride (3 mg·kg·d), by intragastric administration 2 times per day for 10 days. F. velutipes polysaccharides at the doses of 600, 400 and 200 mg/kg (1 mL/100g weight) were administered to treat rats with constipation for 7 days. The gastrointestinal hormones, including motilin (MTL), gastrin (GAS), substance P (SP), somatostatin (SS), and intestinal propulsive rate and feces weight at 24 hours after treatment were used as the indexes to evaluate the effects of F. velutipes polysaccharides on constipation. The levels of MTL, GAS and SP in serum significantly increased and the levels of SS in serum of rats significantly decreased after the treatment of rats with F. velutipes polysaccharides as compared with those of rats in the model group.

Two polysaccharides were isolated successfully from Flammulina velutipes and identified as CHFVP-1 (24.44 kDa) and CHFVP-2 (1497 kDa). Based on the results of Fourier transform-infrared spectroscopy (FT-IR), gas chromatography (GC), gas chromatography–mass spectrometry (GC–MS), and nuclear magnetic resonance (NMR) spectroscopy regarding the structure of CHFVP-1 and CHFVP-2, CHFVP-1 was constructed with the backbone of→6)-α-D-Galp-(1→ and the branch of Galp by an →3,6)-α-D-Manp-(1→attached with T-β-D-Glcp or t-α-L-Fucp side chains. Meanwhile, the CHFVP-2 was a glucan with the construction of →6)-β-D-Glcp-(1→ and T-β-D-Glcp. Moreover, the coagulant activity in vitro of CHFVP-1 and CHFVP-2 was evaluated, and the results showed that CHFVP-1 exerts procoagulant activity by shortening the activated partial thromboplastin time (APTT) and thrombin time (TT), while CHFVP-2 did not reveal a definite coagulant activity. The finding would benefit the further application of F. velutipes in the field of medicine.