Assessing the skin-whitening property of plant extracts from taiwanese species using zebrafish as a rapid screening platform

Zebrafish can be used as a phenotype-based fast-screening platform for the discovery of skin-whitening products by observing the formation of melanin in vivo through a dissecting microscope. In this study, we first evaluated commercial whitening ingredients to confirm the potency of the zebrafish model. The zebrafish screening system verified that verbascoside and 5 other commonly used commercial skin-whitening compounds– including sodium ascorbate, azelaic acid, transamin, kojic acid, and PTU- significantly reduce melanin content in a dose-dependent manner. We subsequently conducted preliminary screening of 123 natural sources to identify those with whitening property. Through a two-step screening process, anti-melanogenesis effects of 4 and 9 candidates at low and high concentration were verified respectively. The toxicity, mortality, and malformation of zebrafish embryo were also evaluated. We further investigated the components of C. manghas L. and found 6 major compounds, one of which was manghaslin, a compound known for its melanin-suppressing effect on zebrafish without cytotoxicity. With these properties, manghaslin is a promising candidate as a skin lightening agent or a treatment for melanoma.