Abstract:
Background: Thai women give precedence to pale skin as one of aesthetic values. Previously, alpha arbutin, a well-known synthetic agent, has been widely used in whitening products. Recently, various kinds of Thai herbs, including Artocarpus Lakoocha ROXB. which contains oxyresveratrol as a major active component, have been rising in popularities due to their skin whitening properties. In vitro studies of dihydrooxyresveratrol, a derivative of oxyresveratrol, indicated more potent anti-tyrosinase activities compared to oxyresveratrol. Nevertheless, in vivo study of its skin whitening efficacy has not been established.
Objective: To compare efficacy of 0.1% dihydrooxyresveratrol and 2% alpha arbutin for facial whitening in Thais.
Material and Methods: Twenty two Thai volunteers whom matched with the inclusion criteria were recruited. 0.1% dihydrooxyresveratrol cream and 2% alpha arbutin cream were randomly applied in a split- face design (right and left sides), twice daily for 12 weeks. Evaluation was performed every 4-week interval using mean melanin index measured by Mexameter MX18, photographs from VISIA® and records of side effects. Volunteers satisfaction was assessed by questionnaires at 12th week.
Results: Twenty volunteers completed the study. Mean melanin index of the sides that applied 0.1% dihydrooxyresveratrol cream (From 289.20 ± 68.96 to 268.20 ± 64.94 at forehead and from 228.30 ± 67.30 to 214.25 ± 60.69 at cheeks) and 2% alpha arbutin (From 296.80 ± 78.84 to 279.40 ± 79.59 at forehead and from 231.05 ± 70.11 to 218.10 ± 63.57 at cheeks) cream demonstrated statistically significant reduction from the baselines at 4th week and 8th week, respectively. However, paired differences of mean melanin index, global photographic scores between both sides revealed no statistically significant in results. Most volunteers rated 0.1% dihydrooxyresveratrol cream as much improvement for satisfactory. Side effects were recognized only mild in both groups.
Conclusion: 0.1% dihydrooxyresveratrol cream is equally effective in facial whitening to 2% alpha arbutin cream.