Caracterização Molecular de óleos fixos de alguns frutos da região Amazônica

Abstract

The economic exploitation of vegetable oil is considered by SUFRAMA (Superintendência da zona franca de Manaus) one of the best possibilities in the region. However there a few studies related to the chemical composition of amazon fruits and tjheir oil. We have studied the chemical composition of four amazon fruits, namely pataua (Oenocarpus bataua), bacaba (Oenocarpus bacaba), uxi-amarelo (Endopleura uchi) and piassava (Leopoldinia piassaba). It is the first report describing the fatty acid, tocopherol and phytosterol composition of piassava fruits. The fatty acid composition was determined by methyl ester conversion and high resolution gas-liquid chromatography and we achieved similar results as the published for pataua, bacaba and uxi-amarelo. Tocopherol composition and quantification was determined by high performance liquid chromatography. Uxi-amarelo had the higher contents of total tocopherols, while pataua the higher amounts of α-tocopherol. The phytosterols were determined by high resolution gas-liquid chromatography with flame-ionization and mass spectrometry detectors. Bacaba and piassava had the higher contents of β-sitosterol. Some biological activities were also determined for the available extracts. The antioxidant activity of methanolic extracts of pataua and bacaba were higher and a antioxidant compound, piceatanol, was also isolated. These extracts also showed the highest capacity to inhibit the enzyme lipoxidase. In the acetylcholinesterase inhibition assay, bacaba had lower capacity, but pataua showed good capacity. The extracts of piassava and bacaba showed also good larvicidal activity in the assays with Aedes aegypti and Culex quinquafasciatus. The chemical and biological results obtained by this study will help the use and development new products from the extracts of these fruits.