| 摘要 |
PROBLEM TO BE SOLVED: To obtain a preparation for external use for the skin having excellent effect on skin whitening and color fading after pigmentation due to suntan, freckles and chloasma, etc., through suppressing melanogenesis, and also high in safety. SOLUTION: This preparation for external use for the skin contains 0.005-20wt.% of a compound of formula I (R is formula II or formula III). The compound of formula I, which has melanogenesis-suppressive effect and tyrosinase-inhibitory effect, is known as a precursor ofγ-irone andα-irone, each being a perfume ingredient. Of the compounds of formula I, the compound where R is formula II is named as iriflorental, while the compound where R is formula III iripallidal. These compounds can be obtained by subjecting an Iridaceae plant, especially Iris florentina of the family Iridaceae to extraction with a solvent followed by partition and purification of the resultant extract. |
