706 0009-3130/20/5604-0706  2020 Springer Science+Business Media, LLC Chemistry of Natural Compounds, Vol. 56, No. 4, July, 2020 B R I E F C O M M U N I C A T I O N S FATTY ACID COMPOSITION OF THE OIL FROM THE FRUIT OF THREE SPECIES OF PALM TREES FOUND IN THE AMAZON: Astrocaryum gynacanthum, Geonoma deversa, AND Iriartella setigera M. C. O. Moura, 1 L. A. M. A. Costa, 2* and A. Flach 2 Palm trees belong to the Arecaceae family and are distributed mainly in the tropical forests of different continents [1]. There are about 2600 species comprising around 240 genera [2]. In Brazil, there are 383 species of palm trees, among which 118 are in the northern region [2]. This area of the country is part of the Amazon biome, which is known for its rich biodiversity. Palm trees are a valuable resource for the riverside inhabitants of this region, as they are used in various rituals and in the manufacture of different ornaments [3]. In regards to the economy, they provide palm tree heart, starch, oils and fibers, as well as raw material for the production of cosmetics [4–7]. In diets they can be ingested as wine, juice, ice cream, and also in natura [6–9]. The objective of the present study was to determine the fatty acid content of the oil of the epicarp and mesocarp fruit of three palm tree species found in Amazonia: Astrocaryum gynacanthum, Geonoma deversa, and Iriartella setigera. For the A. gynacanthum species, analysis of two different parts of the fruit was carried out: the epicarp and the mesocarp. For the G. deversa and I. setigera species, since they have a very thin epicarp that adheres to the mesocarp, making it difficult to separate them from each other, an analysis of the oil from both parts together was done, and it is referred to as mesocarp in this reseach. In the analysis of the chemical composition of the oils, several fatty acids with chains ranging from 4 to 24 carbons were identified (Table 1). A significant amount of palmitic (16:0), oleic (18:1n9c/t), and linoleic acids (18:2n6c) was observed in the analysis of the fatty acid content of the epicarp and mesocarp oils. The analyses show that the extracted oils consist mainly of unsaturated fatty acids (49.90–66.96%), with oleic acid being the major component (32.72–58.90%). Linoleic acid was found in the oil of all species studied, but in greater proportions in the epicarp (15.33%) and mesocarp (18.78%) of the A. gynacanthum species. Among the saturated fatty acids analyzed in all samples, palmitic acid is found in the highest percentage (19.80% to 24.18%), followed by stearic acid (4.99% to 6.14%). In A. gynacanthum, lauric acid was detected in the epicarp (3.81%) and mesocarp (5.83%), while the myristic acid content was 2.77% in the epicarp and 4.19% in the mesocarp. Moreover, 1.14% of tetracosanoic acid (24:0) was detected in the mesocarp of this species. In the I. setigera species, 5.47% lauric acid, 3.53% myristic acid, 2.33% heptadecanoic acid (17:0), 1.25% tricosanoic acid (23:0), and 2.93% tetracosanoic acid were found in the mesocarp. Studies mention palmitic, stearic, oleic, and linoleic acid as the most common ones found in vegetable oils [10]. The acids of the omega-3 and omega-6 families, which are essential fatty acids, are not produced by the human body and are precursors of several other substances that are important in metabolism [10, 11]. α-Linolenic acid (18:3n3), which belongs to the omega-3 family, is present in all the oils studied, but it stands out in the oils of the epicarp (2.49%) and mesocarp (2.71%) of A. gynacanthum. α-Linolenic acid can be found in linseed and nut oils [11]. Linoleic acid (18:2n6c), which belongs to the omega-6 family, was found in all oils, being identified in higher percentages mainly in the epicarp and mesocarp of A. gynacanthum. Some sources of linoleic acid in vegetable oils are corn, sunflower, and soybean oils [11]. 1) Post-Graduate Program in Chemistry, M. Sc. in Chemistry, Roraima Federal University, Roraima, Brazil, fax: +55 95 3621 3137, e-mail: claris.moura@hotmail.com; 2) Chemistry Department, Science and Technology Center, Roraima Federal University, Roraima, Brazil, e-mail: luizufrr@gmail.com, aflach@gmail.com. Published in Khimiya Prirodnykh Soedinenii, No. 4, July–August, 2020, pp. 609–610. Original article submitted June 6, 2019. DOI 10.1007/s10600-020-03124-w