Fig. 3.

The upper arms of ten volunteers were irradiated with UVB exposure at 2 MED. After the irradiation, the irradiated areas were topically treated with 3.0 or 5.0 % (v/v) Platycodon root extract-containing lotion or with a placebo lotion twice a day for 3 weeks. a Photographs at 3 weeks after the irradiation demonstrate the remarkable inhibitory effect of this extract on UVB-induced pigmentation in a dose-dependent manner. b The intensities of pigmentation were measured using a color difference meter. The efficacy of the extract is expressed as the delta L* value compared to that of a placebo lotion. *P < 0.05; **P < 0.01 versus placebo control