Britannilactone(Desacetylinulicin) is a methanol extract of the dried flower of Inula britannica L.IC50 value:Target:A bioassay-guided isolation of the chloroform fraction of the I. britannica using an in vitro melanogenesis inhibition assay led to the isolation of sesquiterpenes, 1-O-acetylbritannilactone (1), britannilactone (2) and neobritannilactone B (3). Compounds 1 and 2 significantly reduced melanin production in a dose-dependent manner with IC50 values of 13.3 and 15.5 μM, respectively [1].
[1]. Choo SJ, et al. Hypo-pigmenting effect of sesquiterpenes from Inula britannica in B16 melanoma cells. Arch Pharm Res. 2014 May;37(5):567-74.