Phenolic compounds increase their concentration in Carica papaya leaves under drought stress

Abstract

Carica papaya L. cv. Maradol is a tropical plant with high commercial value due to its consumption and high nutritional value. Recent studies have corroborated a great diversity of biological activities in extracts from different tissues of the plant that seem to be caused by the presence of phenolic compounds. In this study, the effect of drought stress on the contents of phenolic compounds and the antioxidant capacities of aqueous extracts of papaya leaves were studied. Results show drought stress in plants increased their antioxidant capacity and the content and diversity of phenolic compounds. Several phenolics were identified by high-performance liquid chromatography with photodiode array coupled to electrospray quadrupole time-of-flight mass spectrometry and some of them were exclusively detected in papaya leaves under drought stress. Since this is the first report of the drought stress influence on the accumulation of phenolic compounds in leaves from papaya plants, this research opens many perspectives for obtaining a greater quantity and diversity of phenolics from vegetal tissues under abiotic stress conditions that could be exploited in food, cosmetic and pharmaceutical industries.