Preparation and application of carboxymethylated and phosphatised Melaleuca polysaccharide

Abstract Polysaccharides are a class of biological macromolecules made up of sugar chains with multiple glycosidic bonds. To explore the extracted, purified, carboxymethylated and phosphorylated modified to obtained carboxymethylated polysaccharides (HSPS) and phosphorylated polysaccharides (HSPP), and the HSPS and HSPP were characterized and analyzed, and their antioxidant activity measured. Response surface design was used for the synthesis process of HSPS and HSPP, the structure characterization and antioxidant activities of HSPS and HSPP were evaluated. The results showed that the Mw and Mn of HSP were 14.66 kDa and 8.39 kDa, respectively. The monosaccharides were mainly galactose, glucose, xylose, and arabinose in a molar ratio of 37.68%: 24.43%: 13.63%: 9.18%. The optimal synthesis conditions for HSPS were as follows: reaction time of 2.01 h, reaction temperature of 44.61°C and the amount of monochloroacetic acid necessary was 1.18 g. The optimal synthesis conditions for HSPP were: reaction time of 4.28 h, reaction temperature of 80.78°C, and reaction pH of 8.98. HSPS and HSPP have scavenging effects on ABTS, super oxideanion and hydroxyl radicals. The HSPS and HSPP were characterized and analyzed, and their antioxidant activity measured.