Caracterização química da casca do caule de Bertholletia excelsa, usando a prospecção fitoquímica em tubos, CCD E EM-(-)-APCI

Abstract

Medicinal plants produce a biodiversity of secondary metabolites, whose main function is to protect against abiotic and biotic stresses. In humans, these active principles are responsible for medicinal and pharmacological effects. Bertholletia excelsa (Lecythidacea), is an oleaginous plant native to the Amazon region. The chemical classes commonly identified in the species include phenolic compounds, terpenes, and flavonoids, which are mainly responsible for the antioxidant activity. Recent studies have confirmed the presence of phenolic compounds such as quercetin and protocatechuic acid, which may be related to the free radical kidnapper capacity. In this context, the objective of this work was to carry out a phytochemical study of crude extracts and fractions of the stem bark of the species. Then, the collected plant material was dried, ground, extracted with ethanol 20 and 80% by means of static exhaustive extraction cooled by reflux. The crude extracts were filtered, concentrated and fractionated in ascending order with hexane, chloroform, ethyl acetate and butanol. Then, phytochemical prospecting analyses were carried out in tubes, CCD and MS. Ethanolic extracts 20 and 80% showed total yields of 1.92 and 1.85 %, respectively. In the tube test, the results were based on color change after reaction or precipitate formation. Through the test, the presence of terpenes, steroids, saponins, flavonols and flavanones were characterized. In the CCD test, phenolic acids, flavonoids and terpenes were characterized. An antioxidant activity against DPPH was also observed. In the MS analysis, it was characterized that the majority compounds are fatty acids such as: palmitic acid (255 m/z), oleic acid 281 (m/z), linoleic acid (279 (m/z), stearic acid 283 (m/z) and 9,12, 13-trihydroxy-10-octadecenoic acid (329 m/z), which is consisten with the literature. In addition, the majority presence of a aryltetralin lignan (419 m/z) and a protocatechuic acid (153 m/z) was also characterized in a minority form. Therefore, the antioxidant activity may be associated with the concentration of polar constituents in the samples. This research is of paramount importance and contributes to the known chemistry of the species.