WHITENING AGENT SCREENING METHOD, BONE-FORMING PROTEIN 4 INHIBITOR, COSMETICS, AND METHOD FOR MANUFACTURING COSMETICS

To provide a method for screening a substance useful as a whitening agent by utilizing a mechanism involved in suppressing differentiation and proliferation of melanocytes, a BMP-4 inhibitor as a whitening agent whose usefulness is confirmed by the screening method, and a cosmetic comprising the whitening agent whose usefulness is confirmed by the screening method.SOLUTION: A method of screening for whitening agents uses as an index, decrease in an expression level of melanocyte differentiation-inducing factor in cells exposed to a whitening agent candidate substance relative to the expression level of melanocyte differentiation-inducing factor in a control group in which cells are not exposed to the whitening agent candidate substance. A BMP-4 inhibitor includes at least one of a group consisting of a burnet extract, an aloe vera leaf extract, soymilk fermented liquid, a moth bean seed extract, a horse chestnut extract, a glycyrrhiza extract, and an Angelica keiskei leaf/stem extract. A cosmetic comprises a whitening agent candidate substance whose expression level of melanocyte differentiation-inducing factor is confirmed to be reduced by the whitening agent screening method.SELECTED DRAWING: Figure 2 【課題】メラノサイトの分化及び増殖の抑制に関与する機構を利用して、美白剤として有用である物質のスクリーニング方法、スクリーニング方法で有用性が確認された美白剤としてのＢＭＰ−４抑制剤及びスクリーニングにより有用性が確認された美白剤を含有する化粧料を提供する。【解決手段】細胞に美白剤候補物質を暴露した際のメラノサイト分化誘導促進因子の発現レベルの、細胞を美白剤候補物質に暴露しない対照群におけるメラノサイト分化誘導促進因子の発現レベルに対する低下を指標とする、美白剤のスクリーニング方法。ワレモコウ抽出物、アロエベラ葉抽出物、豆乳発酵液、モスビーン種子抽出物、セイヨウトチノキ抽出物、カンゾウ抽出物及びアシタバ葉／茎抽出物からなる群のうちの少なくとも１つを含むＢＭＰ−４抑制剤。美白剤のスクリーニング方法によりメラノサイト分化誘導促進因子の発現レベルの低下が確認された美白剤候補物質を含有する化粧料。【選択図】図２