In Vitro Bioactivity of Methanolic Extracts from Amphipterygium adstringens (Schltdl.) Schiede ex Standl., Chenopodium ambrosioides L., Cirsium mexicanum DC., Eryngium carlinae F. Delaroche, and Pithecellobium dulce (Roxb.) Benth. Used in Traditional Medicine in Mexico

Seven out of eightmethanolic extracts fromfive plants native toMexico were inactive against ten bacterial strains of clinical interest. The fruit extract of Chenopodium ambrosioides inhibited the bacteria Enterococcus faecalis (MIC = 4375 mu g/ml), Escherichia coli (MIC = 1094 mu g/ml), and Salmonella typhimurium (MIC = 137 mu g/ml). Thefruit extract of C. ambrosioides was with CC50 = 45 mu g/ml most cytotoxic against the cell-line Caco-2, followed by the leaf extract from Pithecellobium dulce (CC50 = 126 mu g/ml); interestingly, leaves of C. ambrosioides (CC50 = 563 mu g/ml) and bark of P. dulce (CC50 = 347 mu g/ml) extracts weremuch less cytotoxic. We describe for the first time the cytotoxic effect from extracts of the aerial parts and the flowers of Cirsium mexicanum (CC50 = 323 mu g/ml and CC50 = 250 mu g/ml, resp.). Phytochemical analysis demonstrated for both extracts high tannin and saponin and low flavonoid content, while terpenoids were found in the flowers. For the first time we report a cytotoxicological study on an extract of Eryngium carlinae (CC50 = 356 mu g/ml) and likewise the bark extract from Amphipterygium adstringens (CC50 = 342 mu g/ml). In conclusion the fruit extract of C. ambrosioides is a potential candidate for further biological studies.