Effect of Sulfation Modification on Antioxidation and Antitumor Activity of Intracellular Polysaccharide from Chlorella vulgaris

In order to explore the effect of Chlorella polysaccharide sulfation modification on biological activity, Chlorella sp.22 was used as experimental material in this study. The purified polysaccharide HDB-1 was obtained by extracting intracellular polysaccharides and separated and purified by DEAE-52 cellulose anion exchange column. The purified polysaccharide HDB-1 was sulfated to obtain SHDB-1. The antioxidant activity and antitumor activity of polysaccharides before and after sulfation modification were studied. The results showed that the purified component HDB-1 was mainly α-furanose. SHDB-1 was obtained by sulfation modification of HDB-1 by sulfur trioxide-pyridine method. Its degree of substitution was 1.046. The antioxidant activity results showed that the IC50 (semi-inhibitory concentration) values of HDB-1 and SHDB-1 DPPH radical clearance were 29.28 mg/mL and 14.49 mg/mL, respectively. The IC50 values of hydroxyl radical scavenging were 36.75 mg/mL and 28.59 mg/mL, respectively, indicating that the a