Isolation, Structural Characteristics Analysis of a Vigna unguiculata Polysaccharide VUP80-3 and Its Protective Effect on GES-1 Cells In Vitro

Cowpea (Vigna unguiculata) is one of the main edible legume vegetables in China, and it can improve spleen and stomach function. A polysaccharide component (VUP80-3) has been isolated from V. unguiculata in this study. The average molecular weight of VUP80-3 is 6.43 x 10(4) Da, and the main monosaccharide group is glucose. The mass ratio of monosaccharide groups in the polysaccharide was glucose:galactose:arabinose:rhamnose:xylose:mannose:fucose = 152.36:24.50:16.53:8.13:1.26:0.97:0.82. NMR analysis showed that VUP80-3 has & RARR;4)-& alpha;-D-Galp (1 & RARR; and & RARR;4)-& alpha;-D-Glcp(1 & RARR; main chain and & RARR;3,4)-& beta;-D-Glcp(1 & RARR;, & RARR;4,6)-& alpha;-D-Glcp(1 & RARR; branch chains, and the terminal sugar is & alpha;-D-Glcp(1 & RARR;. Biological activity test results showed that VUP80-3 at 1000 & mu;g & BULL;mL(-1) significantly increased the activity of ethanol injured GES-1 cells (p < 0.01) and significantly reduced reactive oxygen species (ROS) in ethanol injured GES-1 cells and inflammatory factors (IL-8, IL-1 & beta; and TNF-& alpha;,) in GES-1 cells. This compound also reduced the apoptosis rate (p < 0.05), thereby significantly reducing the oxidative damage caused by ethanol in GES-1 cells. Therefore, VUP80-3 is a potential drug to protect the gastric mucosa from damage.