RESUMO
Pectis brevipedunculata (Gardner) Sch.Bip., known in Brazil as alecrim do campo, is a small Asteraceae family plant with a calming effect and consumed as tea. This species contains components, such as neral and geranial, that display various biological activities, such as leishmanicidal. The aim was to chemically characterize the essential oil (EO) obtained from P. brevipedunculata (EO-PB) by hydrodistillation and a microemulsion formulated with EO (ME-PB), Tween 80 and Transcutol P, assess the leishmanicidal effect against Leishmania (L.) amazonensis promastigotes and cytotoxicity against RAW 264.7. EO-PB and ME-PB were analyzed by Gas Chromatography Mass Spectrometry (GC/MS). Monoterpene hydrocarbons were noteworthy among the identified compounds. The main EO-PB constituents were α-pinene and limonene, followed by neral and geranial, which were maintained in ME-PB. EO-PB presented an inhibitory concentration (IC50) of 20 µg/mL and ME-PB of 0.93 µg/mL. ME-PB inhibition towards the parasite was 20-fold higher than that of EO-PB. This indicated that EO incorporation to the microemulsion resulted in optimized biological activity. Selectivity indices indicate that ME-PB is more selective concerning parasite inhibition. Thus, ME-PB may comprise an adequate approach against Leishmania, as the inhibitory concentration (IC50) promastigotes was lower than that considered toxic for cells cell cytotoxicity of 50% (CC50).
RESUMO
The genus Arrabidaea, consisting of ~170 species, belongs to the family Bignoniaceae, distributed around the Neotropics and temperate zone. The center of diversity of the family is in Brazil, where 56 genera and about 340 species exist. Most species of the genus Arrabidaea are traditionally utilized as diuretics and antiseptics, as well as for treating intestinal colic, diarrhea, kidney stones, rheumatoid arthritis, wounds, and enterocolitis. The genus is chemically diverse with different substance classes; most of them are triterpenes, phenolic acids, and flavonoids, and they exhibit valuable pharmacological properties, such as antitumor, antioxidant, leishmanicidal, trypanocidal, anti-inflammatory, and healing properties. This review presents information on the chemical constituents isolated from seven Arrabidaea species, and the pharmacological activities of the extracts, fractions and pure substances isolated since 1994, obtained from electronic databases. The various constituents present in the different species of this genus demonstrate a wide pharmacological potential for the development of new therapeutic agents, however its potential has been underestimated.
