Análise fitoquímica e atividade fotoprotetora de extrato etanólico de Euphorbia tirucalli Linneau (Euphorbiaceae)

Abstract

Euphorbia tirucalli Linneau, popularly known as “avelos”, “naked cock” or “naked dog”, is used in popular medicinein order to treat cancer, antibiotic and antiviral diseases. Herbal medicines are often employed in order to assist or replace conventional therapies for the treatment of several diseases, including the prevention of the damage caused by ultraviolet radiation. Thus, the aim of this research was to evaluate the photoprotective potential and phytochemical screening of the ethanol extract of the aerial parts of avelos. The photoprotective activity was assessed by in vitrotrials according to the method adapted from Mansur, using the ethanol extract of the aerial parts. The results showed that the phytochemical study revealed the presence of reducing sugars, alkaloids, phenols, flavonoids, tannins, saponins, steroids and triterpenoids in ethanolic fraction. The extract showed antioxidant activity (EC50) of 16,98 ± 0,35 μg.mL-1, phenolic contents of 96,18 ± 1,33 mg EqAG/g and 63,57 ± 2,74 flavonoids from mg EqC/g that can advantage the photoprotective activity. Assessing the sun protection factor, it can be observed that all the tested concentrations (0,01 to 0,1 μg.mL-1) showed potential for photoprotection from ultraviolet radiation with a range of 6,05 to 19,84 FPS, respectively. These results suggest that the ethanol extract of Euphorbia tirucalli Linneau presents possible photoprotective effect.