Physicochemical properties and antioxidant activity of polysaccharides obtained from sea cucumber gonads via ultrasound-assisted enzymatic techniques
Jingjie Wang, Shuo Shi, Fangfei Li, Xin Du, Baohua Kong, Hao Wang, Xiufang Xia
Abstract
The physicochemical properties and antioxidant activity of sea cucumber gonadal polysaccharide extracted by enzymatic, ultrasound and ultrasound-assisted enzymatic methods were investigated. The results showed that the total sugar and sulphate group content (69.1 g/100 g, 14.7 g/100 g) of SCGP-UAE were higher than those of SCGP-E (58.8 g/100 g, 10.6 g/100 g) and SCGP-U (62.9 g/100 g, 13.3 g/100 g). The zeta potential, molecular weight and particle size of SCGP-UAE were significantly lower than those of SCGP-E and SCGP-U (P < 0.05). Their molar ratios of monosaccharide composition were different. With the concentration of SCGP-E, SCGP-U and SCGP-UAE from 0.25 increased to 4.00 mg/mL, the 1,1-diphenyl-2-picrylhydrazyl radical (DPPH∙), hydroxyl radical (∙OH) scavenging ability and reducing power of them were improved. In the concentration range of 0.50–4.00 mg/mL, the antioxidant ability of SCGP-UAE was higher than SCGP-E and SCGP-U. At 4.00 mg/mL, the DPPH∙, ∙OH scavenging ability and reducing power of SCGP-UAE were 12.8%, 14.6% and 9.42% higher than those of SCGP-U and 38.1%, 29.9% and 29.3% higher than those of SCGP-E, respectively. The strongest antioxidant activity of SCGP-UAE was due to the UAE method degraded SCGP chains and exposed more sulphate groups by breaking glycosidic bonds within SCGP.