Abstract:In this study, the antioxidant activity and protective effect against AAPH-induced oxidative damage in human erythrocytes of the polysaccharides from Broussonetia papyrifera panicle were studied. Broussonetia papyrifera panicle was taken as the raw material, single factor experiments were designed for a hot water extraction method and the extraction process of Broussonetia papyrifera panicle crude polysaccharide was optimized by the response surface method. The evaluation indicators included the scavenging rate of ABTS+∙, DPPH∙ and ∙OH, the reducing ability of Fe3+, and the protective effect against the AAPH-induced human red blood cell oxidative damage, to study the in vitro antioxidant activity and hemolysis inhibition of the polysaccharides. The results showed that the optimal conditions were: solid-to-liquid ratio 1:32.33 (g/mL), extraction temperature 89.89 ℃, extraction time 116.53 min, under which the yield of crude polysaccharide was 23.67%. In the antioxidant experiments, the scavenging rates of ABTS+∙, DPPH∙ and ∙OH of the polysaccharide were 76.92%, 57.81% and 80.76%, respectively. The absorbance of the polysaccharide corresponding to the reducing ability against Fe3+ was 1.66 at a polysaccharide mass concentration of 8 mg/mL and the wavelength of 700 nm. Erythrocyte hemolysis experiments showed that the polysaccharide could effectively inhibit the production of ROS and MDA in the erythrocytes treated by AAPH, reduce the conversion rate of GSH to GSSG, and regulate the enzyme activities of CAT, GSH-PX and SOD to restore normal red blood cell levels. The study confirmed that the polysaccharide from Broussonetia papyrifera panicle possessed good antioxidant capacity and can protect erythrocytes from oxidative damage caused by AAPH. This research aimed to provide a scientific foundation for the study on the bioactive material basis of Broussonetia papyrifera panicle polysaccharides, which is of great significance for the research and development of health food products derived from Broussonetia papyrifera panicle.
