Context: 'Carnauba' wax is a natural product obtained from the processing of the powder exuded from Copernicia prunifera (Miller) H. E. Moore (Arecaceae). This material is widely used in the Brazilian folk medicine, including the treatment of rheumatism and syphilis. Objective: To investigate the antiprotozoal activity of hexane and EtOH extracts from the 'carnauba' wax as well as from the isolated compounds from the bioactive extracts. Material and methods: Two different samples of 'carnauba' (C. prunifera) waxes -types 1 and 4 -were individually extracted using hexane (EH) and EtOH (EE). Aliquots of hexane (type 1 -EH-1 and EH-4) and EtOH (type 4 -EE-1 and EE-4) extracts were tested against promastigote (2-200 lg/mL in DMSO during 48 h at 24 C) and amastigote (3-150 lg/mL in DMSO during 120 h at 37 C) forms of Leishmania infantum as well as against trypomastigote (3-150 lg/mL in DMSO during 24 h at 37 C) forms of Trypanosoma cruzi. Bioactive extracts EH-1 and EE-4 were subjected to a bioactivity-guided fractionation to afford three dammarane-type triterpenoids (1-3). The in vitro antiprotozoal activities of the obtained compounds were evaluated as described above. Additionally, the cytotoxicity activity of compounds 1-3 against mammalian conjunctive cells (NCTC -2-200 lg/mL in DMSO during 48 h at 37 C) was determined. Results: From the bioactive hexane and EtOH extracts from the 'carnauba' (C. prunifera) wax, were isolated three dammarane-type triterpenoids: (24R Ã )-methyldammar-25-ene-3b,20-diol (carnaubadiol, 1), (24R Ã )-methyldammara-20,25-dien-3-one (2) and (24R Ã )-methyldammara-20,25-dien-3a-ol (3). These compounds were identified based on the analysis of NMR and MS spectroscopic data. Compounds 1-3 were effective against the intracellular amastigotes of L. infantum, with IC 50 values ranging from 8 to 52 lM, while compounds 1 and 3 displayed activity against trypomastigote forms of T. cruzi with IC 50 values of 15 and 35 lM, respectively. The mammalian cytotoxicity assay demonstrated no damage to NCTC conjunctive cells up to 200 lM, except for compound 1, which demonstrated a CC 50 value of 34 lM. Conclusion: Based on the results, it was possible to conclude that the detected antiprotozoal bioactivity of 'carnauba' (C. prunifera) wax extracts could be related to the presence of the natural dammarane triterpenoid derivatives. The results suggested that these compounds could be used as promising scaffolds for drug design studies for leishmaniasis and Chagas disease. ARTICLE HISTORY

Context: Cenostigma macrophyllum Tul. var. acuminata Teles Freire (LeguminosaeCaesalpinioideae) is popularly known as ''caneleiro''. Previous studies showed antioxidant action and analgesic effects of the ethanol extract from the leaves of C. macrophyllum. The phytochemical evaluation of the stem bark revealed the presence of antinociceptive compounds. Objective: To investigate the antinociceptive actions of the ethanol extract and ethyl acetate fraction from C. macrophyllum stem bark in streptozotocin (STZ)-induced diabetic rats and the involvement of opioid and nitrergic mechanisms. Materials and methods: STZ-rats received the ethanol extract (E.EtOH 200 and 300 mg/kg, p.o.) during 5 weeks. In acute experiments, untreated diabetic rats were treated with the ethyl acetate fraction (F.EtOAc 250 and 500 mg/kg, p.o.), on the 28th day of diabetes induction when the opioid and nitrergic mechanisms were investigated. The mechanical nociceptive threshold (MNT) was determined by application of von Frey filaments. Results: Data show that STZ-induced diabetic rats developed a significant tactile allodynia during 5 weeks. Diabetic rats that received E.EtOH (200 and 300 mg/kg) and F.EtOAc (250 and 500 mg/kg) had a pain threshold higher than those in the STZ-vehicle group. F.EtOAc effects were inhibited by pretreatment with naloxone and were not influenced by L-arginine. Discussion and conclusion: The results suggest that the ethanol extract and ethyl acetate fraction of C. macrophyllum presented antinociceptive activity. Thus, F.EtOAc may be exerting its effect by affecting the opioid system, but nitrergic mechanisms are not detectable. The observed activity may be due to its gallic acid, lupeol and bergenin content.

Phytochemical investigation from carnauba (Copernicia prunifera) wax led to the identification of sixteen dammarane-type triterpenes, including thirteen new characterized as: (24R*)-methyldammara-20,25-dien-3α-ol and a mixture of alkyl (24R*)-methyldammar-25-en-20-ol-3β-carboxylates, together with three previously described triterpenes: carnaubadiol, (24R*)-methyldammara-20,25-dien-3β-ol and (24R*)-24-methyldammara-20,25-dien-3-one. Moreover, four fatty alcohols (eicosanol, docosanol, tetracosanol and hexacosanol) as well as four sterols (cholesterol, campesterol, stigmasterol, and sitosterol) were also obtained. These compounds were isolated using classical chromatographic methods and their structures were determined by spectroscopic and chemical methods.