percent (v/v) ethanol as vehicle control was included in each
experiment and did not significantly alter cell viability of SKMEL-
28 (data not shown).
In contrast, these three xanthones caused less cytotoxicity on
normal skin fibroblast CCD-1064Sk cell line, with IC50 values of
7.27, 11.33, and 10.35 lg/ml for a-mangostin, c-mangostin and
8-deoxygartanine, respectively (data not shown).