Evaluation of Antioxidant Activity of Australian Tea Tree (Melaleuca alternifolia) Oil and Its Components

Abstract

Antioxidant activity of Australian tea tree (Melaleuca alternifolia) oil (TTO) was determined using two different assays. In the 2,2-diphenyl-1-picrylhydrazyl assay, 10 microL/mL crude TTO in methanol had approximately 80% free radical scavenging activity, and in the hexanal/hexanoic acid assay, 200 microL/mL crude TTO exhibited 60% inhibitory activity against the oxidation of hexanal to hexanoic acid over 30 days. These results were equivalent to the antioxidant activities of 30 mM butylated hydroxytoluene in both tests at the same experimental conditions. This indicated that the TTO could be a good alternative antioxidant. Inherent antioxidants, i.e., alpha-terpinene, alpha-terpinolene, and gamma-terpinene, in the crude TTO were separated and identified chromatographically using silica gel open chromatography, C(18)-high-pressure liquid chromatography, and gas chromatography-mass spectrometry. Their antioxidant activities decreased in the following order in both assays: alpha-terpinene > alpha-terpinolene > gamma-terpinene.

Antioxidant and Antiproliferative Properties of the Essential Oils of Satureja thymbra and Satureja parnassica and their Major Constituents

“…Similarly, in another study, γ-terpinene had a significant antioxidant activity, comparable to that of α-tocopherol, a known antioxidant (19). Conversely, more recently it was considered to possess moderate antioxidant capacity, but the concentrations that were used in that study were quite high (0-180 mM) (25). Finally, its IC 50 value was found to be 30 mM using the DPPH assay after an incubation period of 26 h (26).…”

Hepatoprotective and antioxidant activity ofMelaleuca styphelioideson carbon tetrachloride-induced hepatotoxicity in mice

“…Different Melaleuca species are used in the traditional medicine for the treatment of several ailments (Southwell & Robert, 1999). Several studies have proved the strong in vitro antioxidant activity of various Melaleuca species (Farag et al, 2004;Kim et al, 2004). M. styphelioides, known as prickly-leaf tea tree, is a small to medium-sized ornamental tree (Byrnes, 1986).…”

Effect of Microemulsions of Essential Oils on Human Erythrocyte and Pathogens Bacteria

“…Esto nos podría indicar que las formas en las que se prueban los antioxidantes pueden estar en función de su disponibilidad de sus componentes bioactivos. Por otro lado, podemos mencionar que AET ha sido reconocido por su capacidad antioxidante, particularmente por la presencia de α-terpineno [23] . La estimación de la capacidad antioxidante de AET ha sido reportada por DPPH o ABTS u otros métodos que se fundamentan en reacciones químicas in vitro y que puede ser diferente a lo que realmente sucede en el cuerpo humano.…”