Estudo fitoquímico, avaliação do potencial antioxidante, teor de flavonoides e toxicidade de Xylosma benthamii

Abstract

The Brazilian territory has a great plant biodiversity, consequently a vast diversity of active substances with therapeutic properties, which promote innovations in the treatment of diseases. The species Xylosma benthamii, which is popularly known as Pustameira, belongs to the genus Xylosma of the Salicaceae family, is widely used in the Delta do Parnaíba-PI region for the treatment of wounds and stomach problems. From this, the objective of this work was to carry out the phytochemical analysis, antioxidant potential, total flavonoid content and toxicity of the ethanol extract of leaves, stems and roots of Xylosma benthamii. Thus, the yield of EER, EEC and EEF of the species, gave respectively 13.71%, 6.27% and 25.03%. The TLC chromatographic profile allowed the identification of substances from the flavonoids and terpenoids class. The phytochemical tests showed the presence of tannins, flavonols, dihydroflavonols, coumarins, leucoanthocyanidins, steroids, saponin heterosides and alkaloids. As for FLAT, it was observed that EEF had a higher content of total flavonoids (175.22 ± 0.89 mg ER/g EtOH) compared to the other extracts. In the toxicity test, the EER showed LD50 = 275.42 mg/mL, evidencing a toxic character. For the EEC, the LD50 = 951.26 mg/mL was obtained, conferring a low toxicity. As for the EEF, the LD50 = 8,755.88 mg/mL, which gives it a non-toxic character. Antioxidant activity was performed only for the EER of X. benthamii. From this, it was found that at the concentration of 250 mg/mL, after 30 min the percentage for the extract was 22.6% ± 2.44, which is lower than the positive control of rutin (94.14 ± 0.22) and BHT (89.88 ± 0.83). Making sure that the EER has a weak antioxidant activity, which may be due to the low content of total flavonoids observed in the extract. This is the first report on the phytochemical analysis, antioxidant potential, total flavonoid content and toxicity for X. benthamii, which contributes to the chemical-pharmacological prospection of the species.