Evaluation of Photoprotective Potential and Percutaneous Penetration by Photoacoustic Spectroscopy of the Schinus terebinthifolius Raddi Extract

Schinus terebinthifolius is a plant rich in phenolic compounds, which have antioxidant properties and can provide new opportunities for treatment and prevention of diseases mediated by ultraviolet radiation like photoaging and skin cancer. The aim of this study was to evaluate the photoprotective potential and ex vivo percutaneous penetration of the crude extract of Schinus terebinthifolius leaves. The extract was tested for antioxidant activity using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) method and -carotene bleaching test. The sun protection factor was also evaluated. The ex vivo skin permeation of the emulsion and gel formulations were assayed. Fractionation of the extract resulted in gallic acid, ethyl gallate and a mixture of flavonoids, suggesting derivatives of quercetin and myricetin. The phenolic content of the extract was 384.64 +/- 2.60mg GAEg(-1) extract. The antioxidant activity was superior to butylated hydroxytoluene, in DPPH method, and ascorbic acid and rutin, in -carotene bleaching assay. The extract showed UV absorption with photoprotector potential in the UVB region. The photoacoustic spectroscopy measurements confirmed absorption in the UV region and topical application of the formulations caused no histological changes in the rats' skin. These results suggest that the crude extract of Schinus terebinthifolius leaves may be a promising natural sunscreen product.