Preliminary screening of some traditional Zulu medicinal plants for antineoplastic activities versus the HepG2 cell line

Aqueous and methanol extracts of nine traditional Zulu medicinal plants, Cissus quandrangularis L., Cyphostemma flaviflorum (Sprague) Descoings, Cyphostemma lanigerum (Harv.) Descoings ex Wild and Drum, Cyphostemma natalitium (Szyszyl.) J. v. d. Merwe, Cyphostemma sp., Rhoicissus digitata (L. F.) Gilg and Brandt, Rhoicissus rhomboidea (E. Mey. Ex harv.) Planch, Rhoicissus tomentosa (Lam.) Wild and Drum, R. tridentata (L. F.) Wild and Drum and Rhoicissus tridentata (L. F.) Wild and Drum subsp. cuneifolia (Eckl. and Zeyh.) N. R. Urton, all belonging to the Vitaceae family, were evaluated to determine their therapeutic potentials as antineoplastic agents. The antiproliferative activity in vitro against HepG2 cells was determined. Twenty-two of the twenty-seven crude plant extracts showed activities ranging from 25% to 97% inhibition of proliferation when compared with the control which showed no inhibitory activity. Higher degrees of growth inhibition were found in aqueous root extracts in comparison with the methanol extracts of the same plant parts. The results show potential antineoplastic activity, indicating some scientific validation for traditional usage. (C) 2000 John Wiley and Sons, Ltd.