Objective:To study the inhibitory effect of flavonoids from Seriphidium santolium on the proliferation of the lung carcinoma A549 cell line. Method: Six flavonoids were isolated by column chromatography on silica gel. They were identified as hispidulin

arteanoflavone

5

7

4'-trihydroxy-6

3'

5'-trimethoxyflavone

eupatilin

quercetagetin-3

6-dimethyl ether-7-O-β-D-glucoside

luteolin-7-O-β-D-glucoside-(3'-O-7″)-quercetin-3″-methyl ether. MTT was performed to examine the proliferation of A-549 cells

and flow cytometry was used to determine the cell cycle distribution and cell apoptosis. Result: There was a dose-dependent inhibition of cell proliferation of A-549 by five compounds. The antiproliferative effect of compound Ⅰ(hispidulin) was attributed to its inducing cell cycle (G1) arrest

and compound Ⅲ(5

7

4'-trihydroxy-6

3'

5'-trimethoxyflavone) attributed to its inducing cell cycle (G2) arrest. Compound Ⅳ (eupatilin) induced the apoptosis and inhibited the cell circle of A-549 cell. Conclusion: Flavonoids from S. santolium could exert an anti-lung cancer effect via induction of cell cycle arrest or cell apoptosis.