Abstract:To explore the effects of different extraction methods on antioxidant and hypoglycemic activities of polysaccharides from fried malt，the polysaccharides from fried malt were extracted by ultrahigh pressure extraction （UHPE），ultrasonic assisted extraction（UAE），and heat reflux extraction（HRE），respectively. The yield and structure of polysaccharides under different extraction methods were compared. The scavenging ability of polysaccharides on DPPH，ABTS+，and hydroxyl radicals was determined to evaluate their antioxidant activity；the in vitro inhibitory activity test of polysaccharides on α-glucosidase and α-amylase was conducted to study their hypoglycemic effect. The results indicated that the yield of polysaccharides under different extraction methods in descending order was HRE，UAE，and UHPE，and the polysaccharides obtained by the three methods all did not contain protein and nucleic acid after purification. The surface of polysaccharides extracted by the HRE method was wrinkled and striped without a triple helix structure，and polysaccharides extracted by UAE had uneven surfaces and dense small strips with a triple helix structure；the polysaccharides extracted by UHPE had multiple circular pores with a triple helix structure. Fourier transform infrared spectrum showed that extraction methods could not change the characteristic functional groups of polysaccharides，but the absorption of some characteristic peaks of polysaccharides shifted to blue or red. The polysaccharides extracted by UAE had the strongest scavenging capacity for DPPH and ABTS+radicals，followed by the polysaccharides extracted by UHPE and HRE. The polysaccharides extracted by UHPE had the strongest scavenging capacity for hydroxyl radicals，followed by the polysaccharides extracted by UAE and HRE，and the inhibitory activity of polysaccharides extracted by HRE on α-glucosidase and α-amylase was the best，followed by polysaccharides extracted by UAE and UHPE.