Physicochemical and functional properties of a water-soluble polysaccharide extracted from Mung bean (Vigna radiate L.) and its antioxidant activity

Abstract

A water-soluble polysaccharide (MBP-1) was isolated from Mung bean (Vigna radiate L.) and its physicochemical characterization, functional properties, and antioxidant activity was investigated. Chemical analysis revealed that the contents of carbohydrate, uronic acid, and protein were 33.05 ± 0.10%, 25.83 ± 0.04%, and 3.17 ± 0.36%, respectively. The molecular weight (Mw) of MBP-1 was 146.22 kDa and it was consist of arabinose (Ara), glucose (Glc), xylose (Xyl), galactose (Gal), and galacturonic acid (GlcA) in a molar ratio of 0.94:0.37:0.33:0.13:5.99. The results of X-ray diffractometry (XRD) and thermal gravimetric analysis (TGA) indicated MBP-1 was semi-crystalline material with better thermal stability. MBP-1 exhibited good hydration properties and oil holding capacity. In addition, the antioxidant assay results showed MBP-1 had high 1,1-Diphenyl-2-picrylhydrazylradical (DPPH) and hydroxyl radical scavenging activities with concentration for 50% of maximal effect (EC50) of 1.59 and 0.51 mg/mL. Overall, these results indicated that MBP-1 presents a promising natural source of food additive or antioxidant.

Keywords: Antioxidant; Functional properties; Mung bean; Physicochemical characterization; Polysaccharide.