Alnus glutinosa (L.) Gaertn. and Alnus cordata (Loisel) Duby as new sources of safe cosmetic and pharmacological anti-melanogenic agents

The genus Alnus (Betulaceae) comprises many species with a long history in traditional medicines. The crude extracts and isolated compounds from Alnus species exhibit a wide spectrum of in vitro and in vivo pharmacological activities (1). Phytochemical investigations revealed the presence of diarylheptanoids, a class of natural products typically found in Alnus genus with two aryl groups joined by a heptane chain in the main skeleton that have drawn attention due to their multiple biological properties and their therapeutic potential (2). A previous study reported that oregonin and other structurally analogous diarylheptanoids isolated from the bark of A. hirsuta showed inhibitory effects o…