ANTIMICROBIAL AND CYTOTOXIC ACTIVITIES OF SOME CRUDE DRUG EXTRACTS FROM MEXICAN MEDICINAL-PLANTS

31 crude extracts derived from 28 plants highly valued as anti-infecti ve agents in Mexican folk medicine have been screened for antimicrobia l activity against four bacteria, a yeast and two molds. The results o f the quantitative study indicated that the extracts derived from five species (Malmea depressa, Heliopsis longipes, Datura lanosa, Cnidoscu lus tehuacanensis and Helianthella quinquenervis) possessed significan t antiseptic properties, therefore supporting the ethnomedical uses of these species. The cytotoxic activity was assayed against three cell lines HT-29 (Colon adenocarcinoma), MCF-7 (Breast carcinoma), A-549 (L ung carcinoma) and only the extract of Helianthella quinquenervis poss essed significant activity against the MCF-7 cell line.