Antioxidant properties of phenolic compounds

The addition of synthetic antioxidants to oils and/or foods is one of the most efficient ways to prevent lipid oxidation. However, the safety of synthetic additives has been questioned stimulating the evaluation of naturally occurring compounds with antioxidative properties. Although there is no assurance of the safety of natural antioxidants, there is some comfort knowing that such antioxidants are purified from natural products that have been consumed for generations. Correspondence/Reprint request: Dr. Zygadlo J.A, Instituto Multidisciplinario de Biología Vegetal CONICET UNC., Cátedra de Química Orgánica, Facultad de Ciencias Exactas Físicas y Naturales, Universidad Nacional de Córdoba, Avenida Velez Sarsfield 1611, X5016 GCA Córdoba, Argentina. E-mail. [email protected] Maestri D.M. et al. 106 Phenolic compounds in plants are recognized as important compounds in conferring stability against oxidation. Natural antioxidant phenolics can be classified into a lipophilic group, tocopherols, and a hydrophilic group, including simple phenolics, phenolic acids, anthocyanins, flavonoids and tannins. Even though chemists have elucidated the structures of thousands of phenolics, there are still many compounds that have not yet been fully characterized and they are referred as phenolic extracts. In this ways berry extracts, aromatic plant extracts, essential oils and their components are gaining interest because of their relatively safe and wide acceptance by consumers. Many authors have reported antioxidant and radical-scavenging properties by berries, spices and essential oils. In this work we reviewed the most important groups of natural antioxidants, with some peculiarities related to chemical composition.