Passion fruit rind, the main by-product of the juice industry, contains pectin, a highly valued functional food ingredient widely used as a gelling agent and stabiliser CH5424802 purchase ( Pinheiro et al., 2008). These rinds have also been studied for use in the production of candy and flour for human consumption ( Ramos et al., 2007). Due to its high nutritional value and flavonoid contents, investigations to evaluate the potential of passion fruit as a functional food or a source of active compounds for antioxidant or anti-inflammatory

purposes are very important. Moreover, although agroindustrial by-products may be rich sources of bioactive compounds ( Balasundram, Sundram, & Samman, 2006), the use of passion fruit rinds still requires further studies. Recent

studies have shown the potential of passion fruit and its rind for several purposes, such as the antihypertensive effect of passion fruit rind attributed partially to the vasodilatory effect of polyphenols, especially the flavonoid luteolin (Ichimura et al., 2006). However, the pulp biological activity that has been the most extensively studied is its antioxidant activity, GS-1101 using various methods, such as DPPH, FRAP, ABTS and DMPD (Kuskoski et al., 2005 and Vasco et al., 2008). These methods explore mainly the stoichiometric activity of extracts by measuring the ability of polyphenolic molecules to trap or neutralise radical species generated by in vitro molecular models. Some in vivo studies have detected anti-inflammatory activity of P. edulis and P. alata leaves ( Vargas et al., 2007 and Zucolotto et al., 2009) by using a carrageenan-induced pleurisy model in mice. These studies showed a decrease of MPO activity, which was associated with a decrease of neutrophil influx. However, the effect of these extracts on ROS produced by stimulated neutrophils

and on the true enzymatic activity of MPO, considered as a target for new drug development ( Malle, Furtmuller, Sattler, & Obinger, 2007) has not been studied. The originality GSK-3 inhibitor of this work was to study the antioxidant activities of passion fruit extracts in a model that distinguishes between two important aspects of the antioxidant activity of a molecule or an extract, either its stoichiometric activity of ROS trapping or its anticatalytic activity by blocking the active site of an oxidant-producing enzyme. In the present study, we assessed the antioxidant activities on phorbol myristate acetate-stimulated equine neutrophils and on purified equine MPO of dry methanol extracts from raw pulp of P. alata and P. edulis and also from the rind of P. edulis fruit infected or not with the passion fruit woodiness virus (PWV) ( Trevisan et al., 2006).