PROBLEM TO BE SOLVED: To provide a new tyrosinase activity inhibitor and a new cosmetic for whitening.SOLUTION: There are provided the tyrosinase activity inhibitor and the cosmetic for whitening containing a substance obtained by treating an extract from Crocus sativus of the genus Crocus of the family Iridaceae with a glucosidase as an active ingredient.COPYRIGHT: (C)2012,JPO&INPIT【課題】新たなチロシナーゼ活性抑制剤及び美白用香粧品の提供。【解決手段】アヤメ科クロッカス属サフラン(Crocus sativus)抽出物のグルコシダーゼ処理物を有効成分とするチロシナーゼ活性抑制剤及び美白用香粧品。【選択図】なし