| 摘要 |
PROBLEM TO BE SOLVED: To obtain the subject inhibitor capable ox specifically and effectively inhibiting the reduction of the immunological function of the skin by ultraviolet rays, capable of maintaining the immunological function in a normal state, and hardly accompanying a topical or constitutional side effect by including a lipoic acid. SOLUTION: The objective inhibitor contains one or more kinds selected from a group of lipoic acid, its salt and its derivative, or one or more kinds of extracts of plants preferably belonging to the genus Pisum. A sodium salt is cited as the salt of the lipoic acid, and alkyl esters are cited as the derivative of the lipoic acid. The proportion of the added inhibitor to a substrate or a carrier is preferably 0.001-5.0 wt.% based on the whole weight. Pisum sativum L. var. arvense Poir. and Pisum sativum L. are cited as the plant belonging to the genus Pisum. The extraction is carried out by dipping the plant in an extraction solvent. The extraction can be carried out while stirring or homogenizing the plant in the extraction solvent (e.g. water and methanol). The extraction temperature is preferably from 5 deg.C to the boiling point of the extraction solvent. |
