Silymarin, a molecule of interest for topical photoprotection

Some UV-filters have side effects. For example, oestrogenic effect was demonstrated for 4-methylbenzylidene camphor. Given that secondary metabolites are known for their UVB photoprotective properties in plants that contain them, we chose to study silymarin as an agent which could potentially be used in sun products. This determination is based on the physical determination of the reduction of the energy in the UV range, through a film of product which has previously been spread on an adequate substrate. About 15 mg of O/W emulsion containing silymarin at various concentrations was applied on roughened PMMA plates and the transmission measurements were carried out using a spectrophotometer equipped with integrating sphere. Incorporated in O/W creams, at a concentration of 10% (w/w), silymarin gives a Sun Protection Factor similar to that of octylmethoxicinnamate, which is why it is predominantly used in Europe. Overall, these results demonstrate that silymarin is a promising new sunscreen agent.