The extracts of Androsace strigilosa, Anemone rivularis, Delphinium brunonianum, Euphorbia longifolia and Thalictrum cultratum exhibited strong cytotoxicity in Vero cells with CC 50 (the concentration that causes the reduction of viable cells by 50%) ranging from 12.5 to 25 mg ml À1 . A moderate cytotoxicity was observed for the extracts of Asparagus filicinus, Bergenia ciliata, Primula involucrata and Saussurea auriculata with CC 50 ranging from 30 to 50 mg ml À1 . Other eight extracts showed very mild toxicity while rest of the extracts were non-toxic at 100 mg ml À1 .