Modified acid polysaccharide derived from Salvia przewalskii with excellent wound healing and enhanced bioactivity

Acid polysaccharide was extracted from Salvia przewalskii root powders (PSP), purified by diethylaminoethyl cellulose column (DEAE-52) and molecular sieve (PSP2). PSPm1 was obtained by modifying PSP2 with nitrite and phosphoric acid. The chemical structure of PSP2 and PSPm1 exhibited notable distinctions, primarily due to the absence of arabinose and promotion of glucuronic acid (GlcA). The structure of PSPm1 was deduced through the utilization of 1H, 13C, and 2-D NMR. The main chain was linked by α-D-Galp(1 → 3)-α-Glcp-(1 → fragments and →6)-β-D-Galp fragments, with the presence of →4)-α-D-GlcpA-(1 → 6)-β-D-Galp-(1 → ， → 4)-α-D-GalAp-(1 → 2,4)-α-D-Rhap-(1 → fragments and →6)-α-Glcp-(1 → 2,4)-β-D-Manp-(1 → fragments. PSPm1 exhibited different immunoregulatory bioactivity in vitro, including haemostatic effects indicated by activated clotting time of 55.5 % reduction by the activated clotting time (ACT) test and wound healing function in vivo. PSPm1 also displayed better anti-tumor biological effects than unmodified. The structure-activity dissimilarity between PSP2 and PSPm1 primarily stems from variations in molecular weight (Mw), monosaccharide composition, and branching patterns. The modification of polysaccharides from the extract residues of Chinese medicinal materials may be a new form of drug supplements.