New C-Deoxyhexosyl Flavones and Antioxidant Properties of Passiflora edulis Leaf Extract

The flavonoids present in passion fruit (Passiflora edulis) leaves were identified by a high-performance liquid chromatography–diode array detection–tandem mass spectrometry (HPLC–DAD–MS/MS) method. Sixteen apigenin or luteolin derivatives were characterized, which included four mono-C-glycosyl, eight O-glycosyl-C-glycosyl, and four O-glycosyl derivatives. With the exceptions of C-hexosyl luteolin and C-hexosyl apigenin, all the compounds exhibited a deoxyhexose moiety. Moreover, the uncommon C-deoxyhexosyl derivatives of luteolin and apigenin have been identified for first time in P. edulis by HPLC–DAD–MS/MS. The antioxidative capacity of passion fruit leaves was checked against DPPH radical and several reactive oxygen species (superoxide radical, hydroxyl radical, and hypochlorous acid), revealing it to be concentration-dependent, although a pro-oxidant effect was noticed for hydroxyl radical.