Abstract: The extraction process and immune function of Corbicula fluminea polysaccharides were studied.Response surface methodology was employed to optimize the extraction process.The results of optimum extraction conditions were as follows:ratio of raw material to solvent 1∶30 ( g/mL ) ,extraction time 102 min and extraction temperature 91 ℃ ,and under these conditions,the average extraction yield was 9.71%.The effect of Corbicula fluminea polysaccharides on the immune function of normal mice was studied.Corbicula fluminea polysaccharides were prepared by the method of water extraction and alcohol precipitation.The mice were divided into blank control group and Corbicula fluminea polysaccharides groups with the dose of 50,100,200 mg/kg·d,respectively.Organ index,macrophage phagocytosis of chicken red blood cells,carbon particle clearance index,organ and body weight ratio,delayed type hypersensitivity reaction(DTH) were analyzed.The results showed that compared with the blank control group,carbon particle clearance index,organ and body weight ratio were increased significantly,and Corbicula fluminea polysaccharides had enhanced mononuclear macrophage function.Conclusion:Corbicula fluminea polysaccharides can enhance mouse immunocompetence and improve the specificity and non-specificity immune function.

Key words: Corbicula fluminea polysaccharides, response surface methodology, process optimization, immunological activity