Characterization of terpene extract from Cannabis sativa flower and evaluation of its anti-melanogenetic effect in melan-a cells

Inhibition of melanogenesis is of major interest in the cosmetic industry. The mechanism underlying melanogenesis includes regulating tyrosinase by activating various signaling pathways, such as protein kinase A and C pathways. Natural material-based agents have recently gained attention as alternative medicines to suppress melanogenic pathways. Cannabis sativa contains many bioactive compounds that are widely used in traditional herbal medicines. The aim of this study was to identify and assess the anti-melanogenic effect of terpene extract from Cannabis sativa flower (TCF) to explore novel depigmenting agents. Gas chromatography-mass spectrometry revealed that TCF contains five monoterpenes, eleven sesquiterpenes, and a diterpene. MTT and melanin content assays demonstrated that TCF significantly decreased the melanin content per live cell in a dose-dependent manner. Tyrosinase inhibition assay showed that TCF exhibited little inhibitory effect on tyrosinase at an equal dose, which reduced the melanin content. However, western blot analysis revealed that TCF downregulated microphthalmia-associated transcription factor (MITF), and tyrosinase-related proteins TRP1, and TRP2 expression by suppressing PKC, p38, and ERK/STAT3, while upregulated Akt pathway in melan-a. These results highlight the potential application of TCF as a natural whitening agent in the cosmetics industry.