Constituintes químicos de sementes de Lecythidaceae ocorrentes em Pernambuco e seu potencial econômico.

Abstract

Many tropical forest plants produce fruits and seed rich in oils, proteins, carbohydrates, and bioactive compounds. Nevertheless, the potential of many species is still unknown. Studying such plants is important for planning sustainable management that generates income from forest preservation, be it through cultivation or reforestation. With that in mind, the present research aimed to analyze the chemical characterization, antioxidant substances and biotechnological use of species of Lecythidaceae. It was determined the proximate composition (Couroupita guianensis Aulb.; Eschweilera alvimii Mori; Eschweilera ovata Mart. ex Miers; Gustavia augusta L., and Lecythis pisonis Camb.), antioxidant substances (total carotenoid, vitamin E, and phytosterols) in Lecythidaceae seeds (Couroupita guianensis Aulb. and the starch, fermentable sugars and ethanol production from E. ovata seeds. L. pisonis and C. guianensis seeds are oily with respectively 58.76% and 35.5% oil content. C. guianensis seeds are a source of linoleic acid and its oil had a tocol content of 25.1 mg/100 g, of which 20.2 mg/100 g are α-tocopherol and 5.0 mg/100 g are γ-tocopherol. Total phytosterols in C. guianensis were 79.81 mg/100 g, among which the major ones were sytosterol (15.28 mg/100 g), campesterol (0.58 mg/100 g), and Δ7-stigmastanol (0.58 mg/100 g). Clerosterol and campestanol were found in trace amounts in the samples studied. E. ovata has the highest total carotenoid content (634.4 μg/g) followed by G. augusta (316.32 μg/g). Among the species analyzed, G. augusta stood out for its aromatic amino acid content, enough to meet the nutritional requirements of 10-12 years old children. C. guianensis seeds, in turn, can supply the sulfated amino acids nutritional requirements of adults with its 1.99 g/100 g. Three of the species analyzed had high percentages of carbohydrates, starch, and fibers: E. alvimii with 23.81, 27.38, and 12.43; E. ovata with 13.66, 50.03, and 13.57; and G. augusta with 16.25, 48.75, and 13.37, respectively. Ethanol production from 2.5 g of dehydrated seed biomass from E. ovata had 52.94% efficiency and 0.27 g/g yield, consuming 59.54% fermentable sugars with 5.91 g/L ethanol produced. In 2.5 g of degreased seed biomass from E. alvimii, E. ovata, and G. augusta, ethanol production efficiency and yield ranged, respectively, from 46.96% and 0.24 g/g (E. ovata) to 62.62% and 0.32 g/g (E. alvimii). G. augusta had the highest ethanol concentration at 2.71 g/L. The most prevalent minerals in E. alvimii, E. ovata, and G. augusta seeds were potassium (641, 479, 716 mg/100 g), phosphorous (389, 223, 147 mg/100 g), and copper (1.37, 0.48, and 0.94 mg/100 g). The present study shows that, besides the oily seeds (L. pisonis and C. guianensis), E. alvimii, E. ovata, and G. augusta are notable sources of carbohydrates, particularly starch, and can be used as raw materials in the food and cosmetic industries. E. alvimii, E. ovata, and G. augusta were the first native Atlantic Forest plants to have their ethanol production from their seed starch investigated, setting new perspectives ahead for the research of this product.