A palmeira Euterpe oleracea (Mart.), conhecida como açaizeiro, é nativa da Amazônia e tem-se destacado pelo potencial dos seus produtos, em especial pela importância econômica para a fruticultura regional. A polpa de açaí contém alto teor de óleo vegetal, cerca de 53% em base seca, e é uma fonte de ácidos graxos essenciais. Neste trabalho, a composição em ácidos graxos da fração lipídica da polpa de açaí foi determinada por cromatografia gasosa de alta resolução. O óleo foi obtido pelo processo enzimático ou por extração com n-hexano. A extração enzimática, em meio aquoso, tem sido indicada como uma alternativa para a obtenção de óleos vegetais derivados de polpas de frutas. Os resultados apresentaram diferenças não significativas na composição em ácidos graxos dos óleos provenientes das diferentes técnicas de extração. Em ambos os casos, houve predominância dos ácidos graxos monoinsaturados (68% a 71%) e de ácidos graxos poliinsaturados (7,7% a 10,6%). Açaí (Euterpe oleracea Martius) is a typical palm tree from the Amazon, growing spontaneously in states of Pará, Amazonas, Amapá and Maranhão. It has been highlighted by the potential of its products, especially because of the economic importance for the regional fruit growing. The açaí fruits are very appreciated by their pulp flavour. In the açaí pulp, there is a significant amount of lipids, around 53%, in a dry basis, turning out to be an excellent source of essential fatty acids. The main purpose of the present work was to establish the fatty acid content in the lipid fraction of açaí pulp using high resolution gaseous chromatography. The açaí oil was obtained by enzymatic technology in water has been indicated as an alternative for vegetable oils extraction from pulp of fruits. A significant difference was not observed in the composition of the fatty acids present in açaí oil obtained from either process. In both cases, the oil is high in monounsaturated fatty acids (68% to 71%) and in polyunsaturated fatty acids (7.8% to 10.6%)

The seed oil of Carapa guianensis (Aublet), a tree from the Meliaceae family commonly known as andiroba, is widely used in Brazilian traditional medicine because of its multiple curative properties against fever and rheumatism and as an anti‐inflammatory agent, antibacterial agent, and insect repellant. Since there is no consensus on the best way to obtain the C. guianensis oil and due to its ethnomedicinal properties, the aim of the present research was to evaluate the chemical composition, free‐radical scavenging activity, and mutagenic and genotoxicity properties of three C. guianensis oils obtained by different extraction methods. The phenolic contents were evaluated by spectrophotometry. Oil 1 was obtained by pressing the dried seeds at room temperature; oil 2 was obtained by autoclaving, drying, and pressing; oil 3 was obtained by Soxhlet extraction at 30–60°C using petroleum ether. The oil from each process presented differential yields, physicochemical properties, and phenolic contents. Oil 1 showed a higher scavenging activity against the DPPH radical when compared to oils 2 and 3, suggesting a significant antioxidant activity. All oils were shown to be cytotoxic to bacteria and to CHO‐K1 and RAW264.7 cells. At noncytotoxic concentrations, oil 2 presented mutagenicity to Salmonella enterica serovar Typhimurium and induced micronuclei in both cell types. Under the same conditions, oil 3 also induced micronucleus formation. However, the present data demonstrated that oil 1, extracted without using high temperatures, was the safest for use as compared to the other two oils, not showing mutagenicity or micronucleus induction.