Antileukemic activity of Bidens pilosa L. var. minor (Blume) Sherff and Houttuynia cordata Thunb.

To evaluate the anti-leukemic activity of Bidens pilosa L. var. minor (Blum e) Sherff and Houttuynia cordata Thunb., cytotoxicity tests with an XTT-bas ed colorimetric assay were used. Five leukemic cell lines, namely L1210, U9 37, K562, Raji and P3HR1, were cultured with hot water extracts of B. pilos a var. minor or H. cordata. Hot water extracts of B. pilosa var. minor inhi bited these five leukemic cells with IC(50)s between 145 mug/ml and 586 mug /ml. The effect was greatest on four cell lines, namely L1210, P3HR1, Raji and K562, with IC50s below 200 mug/ml. and a selective index of more than 5 . Hot water extract of H. cordata inhibited these five leukemic cells with IC50s between 478 mug/ml and 662 mug/ml. The selective index was between 1. 5 and 2.1. B. pilosa var. minor was more effective than H. cordata in inhib iting most of the leukemic cells in our study. We suggest that B. pilosa L. var. minor (Blume) Sherff may prove to be a useful medicinal plant for tre ating leukemia.