PHENOLIC COMPOUNDS AND ANTIOXIDANT ACTIVITY Pavonia glazioviana GÜRKE

Phenolic compounds have been related to several beneficial effects on health. Most of them are due the antioxidant activity played by these natural occurring substances. The phenolic compounds are able to inhibit the formation of free radicals, which can induce oxidative damage to cell biomolecules, being related to the etiology of several diseases. Many compounds from secondary metabolism of plants can play relevant role in human health preventing cell oxidative damage. The present study was carried out with the vegetal specie PavoniaglaziovianaGurke (Malvaceae), known as malva-da-chapada and tampa-cabaca. Chemotaxonomic studies on the family indicated that its species are great producers of phenolic substances, such as phenolic acids, flavonoids, tannins and coumarins. From the species P. glazioviana the isolation of flavonoids has already been reported. The present aimed to quantify the total phenolic content in the ethanolic extract of P. glazioviana as well as to evaluate the antioxidant potential of the studied species. For this purpose, the dried aerial parts of the plant were extracted with ethanol, followed by evaporation of the solvent in a rotary evaporator. In order to quantify the total phenolic content in the obtained extract, the Folin-Ciocalteau spectrophotometric method was carried out. The DPPH (2,2-diphenyl-1-picrylhydrazyl) free radical scavenger method was used to evaluate its antioxidant activity. After analysis, the obtained result was 48.4 mg of EAG/g of ethanolic extract of the species. In the evaluation of the antioxidant activity, the EC50 found was 6.36 mg/mL ± 0.02921. The obtained results indicated that the specie P. glazioviana produces high content of phenolic substances and presents interesting antioxidant activity, being higher than other species of Malvaceaepreviously analyzed.