Antioxidant activity of carboxymethyl (1 → 3)-β-d-glucan (from the sclerotium of Poria cocos) sulfate (in vitro)

(1 → 3)-β-d-glucan derived from Poria cocos hardly exhibits bioactivities. To extend its use, three types of (1 → 3)-β-d-glucan derivatives, which were sulfated (1 → 3)-β-d-glucan (S-P), carboxymethyl (1 → 3)-β-d-glucan (CMP) and carboxylmethyl (1 → 3)-β-d-glucan sulfate (S-CMP), were synthesized. Potential antioxidant activities of S-P, CMP and S-CMP were evaluated in vitro. The experiments of scavenging abilities of free radicals were carried out, such as 1,1-diphenyl-2-picrylhydrazyl (DPPH), superoxide anion and hydroxyl. Deeply study of the derivatives’ inhibitory effect for lipid peroxidation, DNA oxidative damage, erythrocyte hemolysis, and malondialdehyde (MDA) production were determined. And S-CMP significantly (P < 0.01) increased the antioxidant activity of β-glucan. These results showed that multiple modifications of polysaccharides may bring the derivatives with excellent properties and various applications.