Florística e perfil de ácidos graxos em sementes de Cuphea (Lythraceae) em ambientes de Roraima

Abstract

Thus this study aimed to carry out the floristic survey of species of Cuphea in Roraima and characterize the seed fatty acids of native species. For the floristic survey were analyzed herbarium specimens deposited in national herbarium (UFRR, MIRR, INPA and IAN), and materials collected in some regions between 2015 and 2016. For the determinations were used identification keys, descriptions, illustrations, taxonomical, floristic and revisions of the genus. For the analysis of fatty acid composition were collected a seed pool of native species from different regions. The extraction of oil from seeds was based on the Bligh and Dyer method (1959) and derivatization of the oil in the method of Joseph and Ackman (1992). After derivatization was performed the Gas Chromatography equipped with Flame Ionization Detector (GC-FID). The data of the samples were compared to standards of FAME from Supelco. In Roraima were found four species: C. antisyphilitica Kunth, C. melvilla Lindl, C. micrantha Kunth, and C. hyssopifolia Kunth, the latter being new records for the state. The anthropogenic environments and near of buritizais and savannas were the preferred habitats of species. Three species, C. micrantha, C. antisyphilitica, C. melvilla were analyzed by GC-FID to determine the fatty acid profile of their seeds. Together, the species had 18 fatty acids with chains of 8 to 20 carbons. The fatty predominant acid in all species was lauric acid (C12: 0), followed by myristic acid (C14: 0) and palmitic (16: 0). The fatty acid profile of the analyzed species follows the pattern of other species of the genus, with about 50% of lauric acid. This percentage is promising because it is higher than that found in species already used by Brazilian industry for the same product, such as coconut oil (Cocos nucifera L.), palm (Elaeis guineensis Jacq.) and babassu (Orbignya phalerata Mart.).