Avaliação do potencial antioxidante do extrato etanólico da Fruta pitanga roxa (eugenia uniflora l.) No modelo experimental Caenorhabditis elegans

Abstract

World fruit consumption has increased mainly because of its nutritional value and possible therapeutic effects. The pitanga, fruit of the pitangueira (Eugenia uniflora L.), belongs to the botanic family Myrtaceae, is a fruit plant native to Brazil that has a high antioxidant capacity and richness in anthocyanins. The present study aims to investigate the composition of the ethanolic extract of purple pitanga and evaluate its antioxidant effect on the nematode Caenorhabditis elegans. The anthocyanins and phenolic compounds present in the extract were identified and quantified by HPLC-DAD-MS. The treatments were carried out with different concentrations of the purple pitanga extract (5, 50, 100, 250 and 500 μg of Chlorogenic Acid equivalents/ml) applied to C. elegans. After the treatment, survival, longevity, reproduction, resistance to oxidative stress with stressor agents hydrogen peroxide (H2O2 0.6mM) and juglone (75μM), determination of reactive oxygen species, expression of antioxidant enzymes (SOD and CLT) and expression of thermal shock protein HSP-16.2. It was observed that the extract of purple pitanga per se did not significantly alter the survival and egg laying of the worms, but increased the longevity of the worms at concentrations of 100, 250 and 500 μg CAE/ml. Some extract concentrations were also able to protect or reverse oxidative stress induced by H2O2 or juglone. In the assay for the determination of reactive oxygen species with the H2O2 stressor agent, the purple pitanga was able to significantly decrease the reactive species. The purple pitanga extract also significantly increased the expression of SOD and HSP-16.2 protein. These results suggest that purple pitanga has no deleterious effects on worms and significantly protects against induced oxidative stress, indicating a possible antioxidant effect in vivo.