Abstract

The antioxidant and skin whitening properties of essential oils as natural products is the cornerstone to replace synthesized preservatives and to obtain safer source with better biological activities. The present study was designed to investigate the antioxidant and tyrosinase inhibitory activities of twenty essential oils obtained from aromatic plants grown and used in Yemen. Essential oils were hydrodistilled using Clevenger apparatus. The antioxidant activity was examined by three different methods, namely: the ability to scavenge free radicals 2,2-diphenyl-1-picrylhydrazyl (DPPH), the capacity to inhibit lipid peroxidation thiobarbituric acid reactive species (TBARS), and the total reduction power activity (TRPA). The new findings have shown that all the tested essential oils have variable free radical scavenging activity as measured by the DPPH decoloration assay. The new findings have shown that all the tested essential oils have variable antioxidant activities. These activities were dependent on the essential oil and the method used. In addition, the present study showed that most of the tested essential oils have low to high inhibitory effect on tyrosinase inhibitory activity. The current findings suggest that the tested essential oils could be used as an important source for pharmaceutical and neutraceutical applications.

Key words: Antioxidation, essential oils, skin whitening, Ocimumbasillicum,Ocimumforskolie, Thymus laevigatus, Acalyphafruticosa, Conyzaincana.

Abbreviation

Abbreviations: DPPH, 2,2-diphenyl-1-picrylhydrazyl; TBARS, thiobarbituric acid reactive species;TRPA, total reduction power activity; BHA, butylatedhydroxyanisole.