Enhancement of physicochemical properties, antioxidant, antitumor, and anticoagulant activities via acetylation of Hypsizygus ulmarius polysaccharide

A polysaccharide (HUP1) was extracted and purified from Hypsizygus ulmarius fruiting bodies and further acetylated (Ac-HUP1) to improve their physicochemical properties and bioactivities. Chemical and FT-IR spectrum analyses results indicated differences in functionality and activity between HUP1 and Ac-HUP1, demonstrating the efficacy of the acetylation. HUP1 has an acetyl group with a degree of substitution (DS) 0.34. The molecular weight of the modified acetylated derivatives was reduced, according to the HPSEC findings. The native and acetylated polysaccharides included varying molar percentages of Ara, Man, Glu, GlcA, and GalA. The Ac-HUP1 outperformed HUP1 in antioxidant activity using the radical scavengers ABTS, DMPD, DPPH, superoxide, and OH radicals. In addition, Ac-HUP1 demonstrated higher activity in reducing power using Prussian blue, cupric ion, ferric ion, and phosphomolybdenum, as well as in lipid peroxidation inhibition assay. HUP1 and Ac-HUP1 inhibited five cancer cells (HT29, PC3, HeLa, Jurkat, and HepG-2) at concentrations from 10 to 320 mu g mL(-1), and the impact was more pronounced in acetylated derivative, which was determined by MTT assay. Ac-HUP1, compared to HUP1, considerably prolonged the APTT, PT, and TT exhibiting anticoagulant activities. Therefore, acetylation modification may improve polysaccharide'sphysicochemical and biological characteristics, allowing them to be employed in the food, nutraceutical, and pharmaceutical industries.