UPLC-QTOF-MS Analysis of Extracts from the Leaves of Pouteria caimito (Sapotaceae) and Their Antioxidant Activity

Abstract

This study describes the phytochemical profile and antioxidant activity of an extract from the leaves of Pouteria caimito (Sapotaceae). The extract in ethanol was obtained by maceration at room temperature and subjected to the liquid-liquid partition to obtain fractions in hexane and ethyl acetate. Steroids, triterpenes, saponins, alkaloids and flavonoids were identified by the phytochemical prospection of extracts and fractions from the leaves. The analysis of the ethyl acetate fraction by UPLC-QTOF-MS allowed us to identify eight triterpenes, namely, euscaphic acid (1), hyptadienic acid (2), betulinic acid (3), oleanolic acid (4), ursolic acid (5), 3β-(O-p-coumaroyl)- alphitolic acid (6), 3β-(O-p-coumaroyl)-maslinic acid (7) and 3β-(O-p-cou- maroyl)-2-hydroxy-urs-12-en-28-oic acid (8). The ethanol extract and ethyl acetate fraction presented total phenolic contents of 10.6 ± 0.1 and 11.4 ± 0.3 mg GAE g−1, respectively, and considerable antioxidant activity in the DPPH assay with EC50 values of 299.4 ± 1.5 and 391.8 ± 0.9 µg·ml−1, respectively.