Abstract

BORGARELLO, A.V; MEZZA, G.N; SOLTERMANN, A.T  and  PRAMPARO, M.C. Use of a free radical scavenging method on extracts obtained by molecular distillation from oregano essential oil. Lat. Am. appl. res. [online]. 2014, vol.44, n.1, pp.25-30. ISSN 0327-0793.

There is evidence that oregano essential oil has a significant antioxidant effect on the process of lipid oxidation. In order to obtain fractions enriched in antioxidant properties, oregano essential oil samples were processed by molecular distillation. Molecular distillation experiments were done in two groups of tests, using an evaporating temperature between 22 and 30 °C. Pressure was varied between 0.7 and 53 mbar. Antioxidant activity, specifically radical scavenging capacity, was analyzed in the essential oil and the distillates and residues obtained by a free radical scavenging method, using DPPH* (2,2-diphenyl-1-picrylhydrazyl). The results obtained allowed to conclude that the free radical scavenging capacity was increased in the residue fractions obtained by molecular distillation. These fractions were concentrated in thymol. The IC₅₀ values of the residues were similar to the synthetic antioxidant BHT, suggesting that fractions concentrated in oxygen derivatives obtained by molecular distillation could be used in the food industry to retard lipid degradation

Keywords : Essential Oils; Oregano; Molecular Distillation; Thymol; Antioxidants.