Abstract: As one of the most important actice components in Lycium barbarum fruits,Lycium barbarum polysaccharide (LBP) is an important indexes to evaluate the quality of Lycium barbarum fruits.For comparison of the effects of different extraction methods for LBP,single factor and orthogonal test were employed to optimize the extraction process for methods of aqueous extraction,ultrasonic assisted extraction and enzyme assisted extraction.The results showed that the better condition is as follows,for aqueous extraction:temperature 90 ℃,time 3 h,Solid-liquid ratio 1:30 g/mL,for ultrasonic assisted extraction:extraction temperature 60 ℃,extracting time 50 min,Solid-liquid ratio of 1:25 g/mL,pH of 8,and for enzyme assisted extraction:enzymatic hydrolysis temperature 50 ℃,160 min of enzymolysis time with enzyme content of 0.50%,pH of 5.0.Applied to extract the LBP in Lycium barbarum fruits produced in Zhongning,Ningxia province,it was found that the enzyme hydrolysis extraction yield the highest (7.79%),followed by ultrasonic assisted extraction (5.92%),then extraction rate of aqueous extraction of the lowest (4.67%),laid solid foundation for further development and utilization of LBP.

Key words: Lyciumbar barum polysaccharide (LBP), extraction method, optimization