doiSerbia

Investigation into the potential chemical mechanism of the pro-oxidant activity of carotenoids with liposomes under UV-irradiation

Cvetković Dragan J. (Faculty of Technology, Leskovac)
Stanojević Jelena S. (Faculty of Technology, Leskovac)
Cakić Milorad D. (Faculty of Technology, Leskovac)
Marković Dejan Z. (Faculty of Technology, Leskovac)

This study focuses on the behavior of β-carotene and lutein inside multilamellar liposomes under continuous UV-irradiation. The liposomes were obtained by the thin film method and carotenoids (Crts) were incorporated by mixing at various concentrations (0.005, 0.0075, 0.02, 0.07 and 0.5 mol %). Liposomes formation and the presence of Crts inside them were confirmed by SEM microscopy and FT-IR spectroscopy, respectively. The antioxidant/pro- -oxidant activity of Crts inside liposomes was determined by the thiobarbituric acid–malondialdehyde (TBA–MDA) test. The investigated Crts acted more or less unexpected (as pro-oxidants) inside the lipid bilayers, interacting with the UV-produced lipid radicals and simultaneously suffering under the UV-irradiation. Their pro-oxidant activity with liposomes and under UV-irradiation could be explained by the formation of unstable adducts in the reaction with peroxyl radicals, or by Crts-cation radicals formation via the electron transfer mechanism. Such tentatively unexpected behavior of carotenoids should be taken into consideration in further carotenoids-based UV-filters projections in cosmetic formulations for skin protection.

Keywords: β-carotene, lutein, liposomes, UV-irradiation, anti/pro-oxidants

Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. TR-34012