Isolation and Characterization of Isofraxidin 7-O-(6′-O-p-Coumaroyl)-β-glucopyranoside from Artemisia capillaris Thunberg: A Novel, Nontoxic Hyperpigmentation Agent That Is Effective In Vivo

Figure 3

Compound 1 increases melanin secretion and increases the activity of mushroom tyrosinase. (a) Effect of 25 μM compound 1 and 25 μM isofraxidin on melanin secretion by B16F10 melanocytes. Culture media were collected after 60 h treatment. For comparison with known inducers of pigmentation, melanocytes were treated with 100 μM IBMX or 5 μM forskolin, as previously described [13, 14]. Error = SD; for increased melanin secretion compared to untreated cells; for increased melanin secretion compared to isofraxidin; for increased melanin secretion compared to compound 1. (b) Compound 1, but not isofraxidin, increases tyrosinase activity. Mushroom tyrosinase was used to measure tyrosinase activity in a cell-free assay. Error = SD; compared to tyrosinase plus tyrosine.

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