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Oxidative stress is a major factor related to the development of inflammatory diseases, which have traditionally been treated with medicinal plants. Given this relationship, into the research of natural antioxidant sources, the antioxidant capacity profiles of 11 species used in traditional medicine as anti-inflammatories were determined. The antioxidant capacity profile was investigated by using different methodologies that consider electron transfer mechanisms (ET), such as stabilization of the DPPH radical, ferric reducing antioxidant power (FRAP), Trolox equivalent antioxidant capacity (TEAC), and hydrogen atom transfer mechanisms (HAT) such as oxygen radical absorption capacity (ORAC) and the inhibition of lipid peroxidation of lipoproteins through the assessment of conjugated dienes and thiobarbituric acid reactive substances (TBARS). Additionally, the total polyphenol content by the Folin–Ciocalteu method was determined, and the correlation between antioxidant capacity and polyphenol content was estimated. The best amounts of total phenolics and maximum values found in DPPH, FRAP, TEAC, and inhibition of lipid oxidation tests were for extracts of Tibouchina kingii , Pseudelephantopus spiralis , and Mimosa albida . Correlation between polyphenol content with ET tests was observed ( r 2 > 0.85, p

Ethnobotanical and chemotaxonomical studies for antiparasitic activity of Colombian Annonaceae were carried out. In vitro antiprotozoal activity of 36 extracts obtained from six different species was determined against promastigotes of three Leishmania species, epimastigotes of Trypanosoma cruzi and both chloroquine sensitive (F32) and resistant (W2) Plasmodium falciparum. Cytotoxic activity was evaluated in U-937 cells. Active extracts were selected according their selectivity index (SI). Extracts from Annona muricata, Rollinia exsucca, Rollinia pittieri and Xylopia aromatica were active against Leishmania spp. and Trypanosoma cruzi showing IC50 values lower than 25 microg/ml. Hexane extract from Rollinia pittieri leaves was the most selective against Trypanosoma cruzi and Leishmania spp. (IS=10 and 16, respectively). The extracts from Desmopsis panamensis, Pseudomalmea boyacana, Rollinia exsucca and Rollinia pittieri showed good antiplasmodial activity (IC50 < 10 microg/ml). No correlation between antiplasmodial activity and inhibition of beta-hematin production was found. The present study gives specific and useful information about antiprotozoal and cytotoxic activities of some Annonaceae extracts. Results presented here also demonstrate which plants and/or plant parts could be useful in the treatment of leishmaniasis, Chagas' disease and malaria.