Fig. 5
From: The functional property of royal jelly 10-hydroxy-2-decenoic acid as a melanogenesis inhibitor
Time course of skin whitening index (L value) of mice treated with Vaseline only (control, 
), 1% Kojic acid in Vaseline (
), 2% 10-HDA (
), 1% 10-HDA (
) or 0.5% 10-HDA (
) in Vaseline. A total of forty mice were equally divided into five groups, and each group was smeared twice daily in 5 consecutive days a week for 3Â weeks with 0.1Â g Vaseline (control, 
), 1.5% Kojic acid in Vaseline (
), 2% 10-HDA (
), 1% 10-HDA (
) or 0.5% 10-HDA (
) in Vaseline. The L value was measured once a day on the same skin area with a DermaLab® Combo. Averaged L values (n = 8) with an error bar of SD are plotted over the experimental period