Kinetic modeling and evaluation of free radical-scavenging behavior in oils: application to four tropical and subtropical fruits in a DPPH system

Maria Do Socorro Moura Rufino,Ricardo Elesbão Alves,Lailla Sabrina Queiroz Nazareno,Fabiano André Narciso Fernandes

doi:10.1590/fst.03819

Abstract

Abstract A kinetic model was developed to represent the radical-scavenging capacity (RSC) for the oxidation of oils. The model was developed using second-order rate constants (k2) to represent the RSC. The RSC of the oils can be compared by the k2 values indicating their scavenging capacity. Furthermore, the k2 values can be used to determine the decay kinetic of oils prone to attack by free radicals and to determine the amount of antiradicals that should be added as protective agent to these oils. As a case study, the antiradical capacity of four oils produced from tropical and subtropical fruits (avocado, nance, palm and peach palm) were studied using the DPPH• assay.

Highlights

The antioxidant capacity of phenolic compounds has become of interest because of its chemoprotective effect against degenerative diseases, such as cardiovascular and some neurological diseases, as well as its ability to inhibit lipid oxidation in food (Bubonja-Sonje et al, 2011)
The antioxidants in oils have been widely studied by several authors, because they are important in the stabilization of free fatty acids and in the antioxidant activity of phenols and other compounds present in the oils
This rate constant is related to the radical-scavenging capacity (RSC) present in the oils and a higher k2 value corresponds to a better RSC

Summary

Introduction

The antioxidant capacity of phenolic compounds has become of interest because of its chemoprotective effect against degenerative diseases, such as cardiovascular and some neurological diseases, as well as its ability to inhibit lipid oxidation in food (Bubonja-Sonje et al, 2011). The antioxidant action is one of the biological activities originating from essential oils, being responsible for neutralizing the oxidative damages in the cells. This damage results in the proliferation of a chain reaction that damages the biological system, causing a series of pathologies (Viana et al, 2014; Miranda et al, 2016). No research has been found that reports the radical elimination capacity of several oils using a kinetic model. The elimination by radical-scavengers (R ) can be summarized as (Equations 1, 2 and 3):

Objectives

Methods

Results