Assessment of the antioxidant capacity of derivatives of hydroxybenzoic and hydroxycinnamic acids in model-systems in vitro

• Grant number: 13/07119-3
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: July 01, 2013
• End date: June 30, 2014
• Field of knowledge: Biological Sciences - Biochemistry - Metabolism and Bioenergetics
• Principal Investigator: Iguatemy Lourenço Brunetti
• Grantee: Bianca Taíse Roim Varotto
• Host Institution: Faculdade de Ciências Farmacêuticas (FCFAR). Universidade Estadual Paulista (UNESP). Campus de Araraquara. Araraquara , SP, Brazil

Abstract

Phenolic acids are secondary metabolites, produced by many species of plants. Several studies have attempted to prove the beneficial effects of these compounds on human health, especially the actions related to antioxidant properties. The oxidative stress can cause many types cell damage, which contributes to the development of illnesses, such as cancer and neurodegenerative diseases; however, phenolic acids may retard or inhibit the oxidative processes that lead to these disturbances. To validate the study of these antioxidant properties, samples derived from hydroxybenzoic acid (p-hydroxybenzoic, protocatechuic, gallic, syringic and vanillic acids) and hydroxycinnamic acid (p-coumaric, caffeic, ferulic and sinapinic acids) will be analyzed for their capacity to capture radical and the non-radical reactive species, comparing the results with antioxidant standards, such as reduced glutathione, a biomolecule that participates in the endogenous antioxidant system, and Trolox, a synthetic analogue of vitamin E, both of which have recognized antioxidant capacity; in addition, the structural differences between the tested compounds must be taken into account. The analysis will consist of assays of capture of: 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS*+), 2,2-diphenyl-1-picrylhydrazyl (DPPH*), superoxide anion radical (O2*-), hypochlorous acid/hypochlorite ion (HOCl / OCl-), hydrogen peroxide (H2O2) and the crocin bleaching assay. (AU)