Objective: To screen the effective part of anti-ulcer activity from Lyeium barbarum polysaccharide(LBP). Method: We divided LBP into four parts (LBP-1

LBP-2

LBP-3

LBP-4) by DEAE-cellulose ion exchange chromatography. Sixty mice were randomly divided into six groups: normal control group

positive control group

LBP-1 group

LBP-2 group

LBP-3 group

LBP-4 group. The anti-ulcer components were screened by the experiments of absolute alcohol and indomethacid inducing gastric mucosa ulcer of mice. Positive control group received 100 mg·kg-1 sucralfate or ranitidine and LBP groups received 250 mg·kg-1 LBP by ig

twice per day for 7 days. Result: LBP-2 and LBP-4 could inhibitgastric ulcer induced by absolute alcohol significantly(P<0.05)

with the inhibition rate of 77.7% and 80.1%. LBP-2 had also the inhibitory effect on gastric ulcer induced by indomethacid(P<0.05)

with the inhibition rate of 64.7%. Conclusion: LBP-2 and LBP-4 can be considered as active parts from LBP

and LBP-2 has a better activity.