英文摘要 |
Exposure of the skin to sunshine for long periods of time is known to induce different degrees of erythema or skin cancer in the unprotected skin. Within recent years ultraviolet absorbers have become an important ingredient in cosmetic formulae, the majority of which are synthesized artificially. These however may induce some side effects, including allergic and in flammatory reactions, such problems may be solved by the use of natural sunscreens. This study focuses on the natural sunscreen products. The sunscreen index (S. I.) value of the extractions of several Hypericoideae are investigated by using Kumler's method. The ultraviolet absorption of natural sunscreen extractions are discussed. |