Revalorization of Passiflora species peels as a sustainable source of antioxidant phenolic compounds

Abstract

Food industry generates a big amount of residues. Nowadays, there is interest in adding value to these residues with the aim of increasing the sustainability of the food chain and to reduce the environmental impact of this waste whose revalorization could also originate an economical benefit. Passion fruits are cultivated for juice and pulp production generating high amounts of vegetable residues. The scarce information about passion fruit peels confers a high interest to the study of their phenolic profiles. In this work, an efficient extraction method based on pressurized hot water extraction was employed to obtain antioxidants from four Passiflora species peels (P. ligularis, P. edulis, P. edulis flavicarpa and P. mollissima). Antioxidant properties of the extracts were tested by in vitro assays and intracellular reactive oxygen species scavenging. P. mollissima and P. edulis peel extracts presented higher antioxidant capacity and phenolic content than P. ligularis and P. edulis flavicarpa. Tentative structural elucidation of 57 phenolics was achieved by high-performance liquid chromatography-quadrupole-time of flight mass spectrometry. Flavones, chalcones and phenolic acids were the polyphenol classes that may contribute to antioxidant capacity of the Passiflora peel.