G. Bertuzzi, B. Tirillini, P. Angelini, R. Venanzoni, Antioxidative Action of Citrus limonum Essential Oil on Skin. European Journal of Medicinal Plants 01/2013; 3(1):1-9.

The purpose of this study was to investigate the action of Citrus limonum essential oil to control free radical-induced lipid peroxidation and preventing tissue damage in skin. Place and Duration of Study: Department of Internal Medicine (University of Roma “Tor Vergata) and A.R.P.A (Aging Research, Prevention and Therapy Association), between January 2010 and June 2011. Methodology: The essential oil was subjected to GC-MS analysis. The superoxide anion scavenging activity of essential oil was evaluated by the enzymatic hypoxanthine/xanthine oxidase system. The same oil diluted in DMSO or grape-seed oil was spread on the face of human volunteers after UV exposition. A sample of skin lipids was collected and the presence of peroxyl radicals was detected based on the measurement of light emitted (chemiluminescence) when the excited carbonyl and singlet oxygen decay to ground state.

Results: Our data demonstrate that the lemon essential -tocopherol against *O2- and peroxide free radicalaoil is more active than  inhibition at 1:100 dilution. A protocol for controlling free radical-induced lipid peroxidation in human skin was thus proposed.
Conclusion: The scavenging action of lemon essential oil could have a practical application for treating human skin against oxidative damage.

The superoxide anion scavenging activity of Citrus limonum essential oils was evaluated using the enzymatic hypoxanthine/xanthine oxidase system. Among the concentrations tested (Fig.1), the 1:100 dilution of lemon essential oil in DMSO had an *O2 - inhibition that was comparable to that of α-tocopherol. The 1:1000 dilution inhibited *O2 - less than α-tocopherol but the level of inhibition was about 76% and 65% of the α-tocopherol activity on cytochrome C and tetrazolium nitroblue, respectively.


Percentage cytochrome C inhibition and percentage nitroblue tetrazolium Reduction

Test significant from normal control (P < 0.05). Mean ±S.E.M of ten experiments