Determination of Photoprotective Potential in Herbal Sunscreen Formulations Prepared from Atalantia ceylanica (Yaki-narang) Extract.

Abstract

Overexposure to solar ultra-violet (UV) radiation causes various deleterious effects on the human skin such as erythema, wrinkling, hyperplasia, photoaging, photocarcinogenesis etc. Thus synthetic sunscreen formulations are currently used by the local communities to avoid and/or minimize the damage caused by harmful solar UV radiation. Although the synthetic sunscreens are beneficial, the adverse effects associated with those products could not be neglected. It is speculated that some of these adverse effects could be more harmful than exposing the skin to the UV radiation. Thus, there is an increasing demand to produce sunscreens with minimal side-effects. In this respect, development of herbal sunscreen formulations would be an attractive option. The photoprotective capability of Atalantia ceylanica (yaki-narang) leaves was previously proved and the sun protection factor (SPF) of its aqueous-methanolic extract was found to be over 25. In the present study, herbal sunscreens were formulated using an aqueous-methanolic extract of dried leaves of A. ceylanica. Different concentrations (i.e. 25%, 50% and 75%) of the extract was incorporated into an aqueous cream base. Initial in-vitro SPF values of each preparation was calculated using UV absorbance measurements. The lowest SPF value of 5.46 was obtained for 25% extract concentration and the highest SPF value of 27.09 was obtained for 50% extract concentration. Interestingly, the synthetic sunscreen (with benzophenone-4 and TiO2 as active ingredients) used as the positive control was found to possess a SPF value of 5.3. In order to evaluate the photostability, each preparation was exposed to direct sunlight for 7, 14 and 21 days and all the herbal extracts were found to be photostable. Further, the preparation with 50% of the extract demonstrated a broad spectrum of photoprotection. Therefore, further studies on possible cytotoxicity effects of these preparations are in progress to evaluate the suitability of these products towards the development of commercial herbal sunscreens.