Abstract: In this study, 75% ethanol extract from asparagus scraps obtained by ultrasonic-assisted extraction was analyzed for the contents of total saponins, total polysaccharides and free amino acids. Meanwhile, its in vitro effect on the normal and Con A-induced proliferation of mouse spleen lymphocytes was studied, and the effect of oral administration at doses of 25, 100 mg/kg and 400 mg/kg on immune functions in normal mice was also observed. The ethanol extract contained 18.20% total saponins, 14.86% total polysaccharides and 12.63% free amino acids. It had no influence on normal spleen lymphocytes in vitro, whereas the ConA-induced proliferation of spleen lymphocytes could be promoted at 25 mg/kg but suppressed at 400 mg/kg by it. Oral administration of this extract enhanced carbon clearance capacity in mice and the ConA-induced proliferation of spleen lymphocytes. Therefore, this asparagus extract has remarkable immunoenhancing functions.

Key words: asparagus extract, saponin, polysaccharide, free amino acid, immune function