Análise fitoquímica, toxicidadee avaliação das atividades antioxidantee antimicrobianadas folhas de Virola Sebifera (Aubl.)

Abstract

Thecerrado is richin medicinal plants due to its morphological characteristics, presenting diversified chemical constituents with biological potentials. However,studies with medicinal species from the Cerrado in the state of Tocantins, Brazil, are still scarce. In this context, this study aimed to contribute to the expansion of chemical and biological knowledge of the species Virola sebifera, collected in the state of Tocantins.The V. sebifera, popularly known as mucuíba, is a typical species of the cerrado, used in folk medicine for its medicinal properties.The extracts obtained by hot (soxhlet) and cold (ultrasound) methods using hexane, methanol and ethanol solvents were submitted to phytochemical screening and characterized by high performance liquid chromatography (HPLC) and gas chromatography coupled with mass spectrometry (GC/MS).Antimicrobial activity was assessed using strains of Staphylococcus aureus(ATCC6538), Escherichia coli(ATCC 25922), Candida albicans(ATCC 10231), Staphylococcus epidermidis(NEWP0128)and Salmonella typhimurium(NEWP 0028) using the well diffusion method minimum inhibitory concentration (MIC).The antioxidant activity was evaluated by the DPPH method, determination of total phenolics and total flavonoids and toxicity was assessed by the Allium cepamodel and by the erythrocyte osmotic fragilitytest(EOF).Phytochemical screening showed the presence of classes of phenolic compounds such as tannins, flavonoids, anthraquinones and alkaloids, and HPLCidentified catechin, syringic acid, chlorogenic acid, p-coumaricacid, rosmarinic acid, naringin, rutin, hesperidin, morinand quercetin.The GC/MS identified phenolic compounds, lignans, furan, amino acids, ether, aldehyde. All extracts showed satisfactory results for antioxidant activity,with emphasis on the hydroalcoholic extract, which presented an IC50 value = 26,46 ± 0,58 μg/ml, close to the rutin standard.In the antimicrobialbioassays the extracts were sensitive to S. aureus, S. epidermidisand Salmonella.The toxicological test revealed that the extracts induced inhibition in the root system of A. cepaand that there was no toxic activity with the erythrocytes.Therefore, thechemical constituents found in V. sebiferadirect to future studies on its bioactive potential that justify the empirical therapeutic indications.