Background: Phytoclear-EL1, an extract from Euphorbia lathyris seeds, has a whitening effect due to inhibition of tyrosinase activity.
Objective: The purpose of this study was to investigate the inhibitory effect of phytoclear-EL1 on melanogenesis.
Methods: Cultured B-16 melanoma cells and 30 human volunteers were used for in vitro and in vivo studies, respectively. Phytoclear-EL1 was added to the cultured B-16 melanoma cells, and applied to UVB-induced hyperpigmented lesions of human volunteers twice daily for 7 weeks. Changes in the number of B-16 melanoma cells, as well as changes in morphology, melanin content, and tyrosinase activity, were measured and then compared with the normal control and the 10(-3)M arbutin groups. Also, the effect of phytoclear-EL1 on UVB-induced hyperpigmented lesions was examined through subjective and objective measurements.
Results: In the in vitro study (p<0.05), the number, melanin content, and tyrosinase activity of cultured B-16 melanoma cells were decreased in the 5microg/ml phytoclear-EL1 group compared to the control group. On objective assessment with a chromameter, the 0.2% phytoclear-EL1 group had a larger difference in the mean L values before and 7 weeks after applying phytoclear-EL1 as compared to the other groups. On subjective assessment by both the researchers and subjects 7 weeks after applying experimental materials, the 0.2% phytoclear-EL1 group and positive control (3% arbutin) had higher scores than the placebo groups. These results demonstrated that phytoclear-EL1 in vivo and in vitro had an inhibitory effect on melanogenesis.
Conclusion: Phytoclear-EL1 may be a candidate extract in the control of hyperpigmentary disorders.
Keywords: Euphorbia lathyris; Melanogenesis; Phytoclear-EL1.