Investigação do potencial de aproveitamento de cascas de pitaya de diferentes espécies para obtenção de extratos antioxidantes

Abstract

The pitaya, a cactácea that produces exotic fruit, has been increasingly consumed, and with this there is the generation of the residues of the fruit, mainly its bark. The use of these wastes can minimize environmental impact, add value, contribute to sustainability and thus reduce environmental damage. Among the possibilities of use is its use as a natural antioxidant source, which has advantages because it can be used as an alternative to the use of synthetic antioxidants, which have been reported as harmful to health. The objective of this study was to evaluate and to compare the bark of the fruits of three different species of pitaya, red of white pulp, red of red pulp and yellow of white pulp, as natural sources of extracts with antioxidant potential. The ethanolic extracts of lyophilized peels were obtained by ultrasonic assisted maceration. The evaluation of the antioxidant potential was made by the dpph method and the total phenolic content (TFT) by the folin-ciocalteu method. For the dpph method, the ethanolic extract of the red pitaya bark presented higher antioxidant potential than the other investigated species, with EC50 value of 17.92 mg ml-1, followed by the white pitaya peel, which in turn was better than yellow pitaya shell. As for phenolic compounds, the total phenolic content of the yellow pitaya shell extract presented significantly higher TFT (0.708 ± 0.026 mg EAG g-1) to the other pitaya species studied, followed by the white pitaya shell extract, and then of the red pitaya. The results obtained allow to conclude that the bark of pitaya presents compounds with antioxidant action, so that it can be considered its use as source of natural antioxidants.