[Problem] Glutathione is known to have various beauty effects such as a high melanin production inhibitory action and antioxidant action. Although glutathione is classified as a pharmaceutical in Japan, it cannot be used in food products. However, the demand for such properties in food products has grown, particularly in recent years. [Solution] A glutathione-containing yeast extract that was extracted from a yeast already used in food and recognized as safe was confirmed to have an effect of inhibiting melanin production by mouse B16 melanoma cells, and, compared to glutathione alone at the same concentration, a superior melanin production inhibitory effect at least twice as strong could be obtained.麩胱甘肽雖已知有高度的黑色素產生抑制作用或抗氧化作用等各種的美容效果，但在日本國內仍是歸類為醫藥品而無法利用於作為食品。然而，尤以近年來食品要求此種機能。針對萃取自有食用經驗且安全性被認可之酵母的含麩胱甘肽之酵母萃取物，利用小鼠B16黑色素瘤細胞來確認抑制黑色素產生的效果，結果確認了：與同濃度的麩胱甘肽單質相比可獲得2倍以上之優良的黑色素產生抑制效果。
