Total phenolic content and antioxidant potential of ‘ora-pro-nobis’ leaves: an in vitro comparative study between pereskia aculeata miller and pereskia grandifolia haw

The ora-pro-nobis is an unconventional vegetable belonging to the genus Pereskia and native to South America. In Brazil, the two species P. aculeata and P. grandifolia are native to the Atlantic Forest and their leaves are widely used for the preparation of different regional dishes. The aim of the present work was to evaluate, in a comparative fashion, the total phenolic contents and antioxidant potentials of P. aculeata and P. grandifolia leaves. For this purpose, the efficiency of three extraction media, namely 70% ethanol in water, water at room temperature and water at 50 ºC, were used for obtaining the interest compounds. Furthermore, the antioxidant capabilities of the prepared extracts were assessed using a set of four different in vitro chemical methods. The results obtained in this work indicate that the ora-pro-nobis leaves (P. aculeata and P. grandifolia) are sources of phenolics with promising antioxidant activity. The hydroethanolic extraction was the most suitable for extracting bioactive compounds from the leaves of both species. In addition, it was found that the extracts of P. aculeata had not only a higher phenolic content but also superior antioxidant capacities, assessed by 4 different methods (DPPH, ABTS, FRAP and ORAC), than the extracts of P. grandifolia.