Atividade antioxidante e antimicrobiana in vitro de extratos de caqui (Diospyros kaki L.) cultivar Rama Forte In vitro antioxidant and antimicrobial properties of persimmon (Diospyros kaki L. cv. Rama Forte) extracts

Summary The antioxidant and antimicrobial properties of various phenolic compounds and plant extracts have been evaluated in many experiments. The aim of this study was to obtain a crude hydroethanolic extract of persimmon (Diospyros kaki L.) cv. Rama Forte and fraction it using solvents with different polarities. Subsequently the total phenolic compounds and in vitro antioxidant and antimicrobial activities were determined in the crude hydroethanolic extract of persimmon, as well as in the hexane, chloroform, ethyl acetate and residual fractions obtained from it. The total phenolic compounds were determined by the Folin-Ciocalteau method, the antioxidant activity by the free radical scavenging 2,2-diphenyl-1-picrylhydrazyl (DPPH) method, and the antimicrobial activity by the disc diffusion method. The phenolic compound contents of the crude hydroethanolic extract of persimmon cv. Rama Forte, the residual aqueous fraction, ethyl acetate fraction, hexane fraction and chloroform fraction were, respectively, 1277.94, 1231.23, 37.24, 17.60 and 11.48 mg GAE.100 mL -1 . The crude hydroethanolic extract of persimmon cv. Rama Forte and the residual fraction showed the highest contents of phenolic compounds and highest anti-radical activities against DPPH, as compared to the other fractions tested, with IC 50 values of 0.2467 and 0.2567 mg.mL -1 , respectively. The persimmon extract and fractions showed no in vitro antimicrobial activity against the microorganisms tested. The results showed that the crude hydroethanolic extract of persimmon cv. Rama Forte and the residual fraction contained sufficient amounts of phenolic compounds to contribute positively to the antioxidant activity.