Abstract: Polysaccharides（PS） were extracted from Lonicera Japonica branches by water-extraction and ethanol precipitation with ultrasonic assistance.The crude polysaccharide was purified through decoloration with petroleum ether and deproteinized by Sevag method.Purified polysaccharide was determinated by Thin Layer Chromatography (TLC),Infrared Spectroscopy (IR) and Ultraviolet spectroscopy (UV).The antioxidant activities of purified polysaccharide to lipin were investigated. The results showed that yield of crude polysaccharides was 13.20% and glucose component was 70.30% in purified polysaccharides.Mannose and Maltose were detected in purified polysaccharides after HCl hydrolysis.Purified polysaccharide exhibited good inhibitory effect to peroxidation of oils and fats,although its antioxidant activity was weak compare to that of Vc and citric acid.

Key words: Lonicera Japonica branches, Polysaccharide(PS)；Component determination；Antioxidant activity to lipin