arbutin and costunolide

Ten compounds were isolated from the EtOAc soluble part of the MeOH extract of Saussureae Radix, with their effects on melanin production also evaluated in B-16 mouse melanoma cell lines stimulated with 3-isobutyl-1-methylxanthine (IBMX), an elevator of cellular cAMP. The compounds were identified as aplotaxene (1), 1 beta-hydroxy arbusculin A (2), costunolide (3), dehydrocostuslactone (4), 11 beta,13-dihydrocostunolide (5), reynosin (6), heptadec-(9Z)-enoic acid (7), beta-sitosterol (8), linoleic acid methyl ester (9) and betulinic acid methyl ester (10). Compounds 2, 9 and 10 were identified from Saussureae Radix for the first time. Furthermore, compounds 2, 3 and 6 showed potent inhibitory effects on the IBMX-induced melanogenesis, in dose-dependent manners, with IC50 values of 11, 3 and 2.5 microg/mL, respectively. As a positive control, arbutin exhibited an IC50 value of 29 microg/mL.

Topics: 1-Methyl-3-isobutylxanthine; Animals; Arbutin; Cell Line, Tumor; Dermatologic Agents; Dose-Response Relationship, Drug; Magnetic Resonance Spectroscopy; Melanins; Melanoma, Experimental; Mice; Molecular Structure; Phosphodiesterase Inhibitors; Plant Roots; Saussurea; Sesquiterpenes; Skin Pigmentation