Ectoine是一種存在嗜鹽性微生物內發現的一種生物分子,其作用在於保護細菌以利存活在高滲透壓以及一些極端惡劣的環境,如脫水、加熱、冷凍和乾燥等。目前有文獻指出Ectoine具有防曬、抗老化、保持皮膚彈性、抗氧化、抗UV等多種功效,然而卻只有少數美白能力相關的報導。 因此在本研究中,以老鼠黑色素瘤細胞株(B16-F0)與人類黑色素瘤細胞株(A2058)做為測試平台,測試Ectoine是否具有美白的能力。實驗結果顯示,在不影響細胞存活率的前提下,細胞內的黑色素含量明顯地受到Ectoine所抑制,在於B16-F0細胞株與A2058細胞株之下其IC50值分別為 156.50 μM和432.42 μM。在於酪胺酸?的活性抑制效果上,皆與兩株細胞株接觸的Ectoine濃度成正比分別為 879.22 μM和470.80 μM。而在Real-time PCR實驗中,發現了對於B16-F0細胞株,其中的酪胺酸?、TRP1、TRP2與MITF的表現皆會受到Ectoine所影響。而A2058細胞株中,卻只有TRP2與MITF的表現會受到Ectoine所影響。在於蛋白質表現上,這兩株細胞株對於酪胺酸?、TRP1、TRP2與MITF的表現皆有影響。基於目前的實驗結果確定了Ectoine具有美白的能力。
In order to search new agents with a depigmenting effect, we have found Ectoine derived from halophilic microorganism. The role of ectoine has been studied extensively with regard to not only the protection of cells from high external osmolarity but also the stabilization of biomolecules in cells against dehydration, heating, freezing or drying. Now many reports claimed that Ectoine has variey of biological activities, including sunscreen, anti-aging, maintenance of skin elasticity, antioxidant and anti-UV. In this report, we studied ectoine on its function in the skin-whitening area. Firstly, we selected mouse melanoma cell line(B16-F0)and human melanoma cell line(A2058)as testing cells in all of our experiments. The ectoine showed low cytotoxicity even at 500 μM. Secondly, we evaluated melanogenesis effect and tyrosinase relative activity by treating melanoma cells with different concentration of ectoine. The ectoine inhibited melanin formation in B16-F0 and A2058 melanoma cell lines with IC50 values of 156.50 and 432.42 μM, respectively. In addition, ectoine displayed a significant inhibitory effect on cellular and mushroom tyrosinase activity. The analysis of inhibitory kinetics revealed that ectoine acted a noncompetitive inhibitory effect on tyrosinase. Importantly, we found that the melanin content and tyrosinase activity were decreased obviously with increasing concentration of ectoine. In the Real-time PCR experiments,we found that the B16-F0 cell line, tyrosinase, TRP1, TRP2 and the MITF will be Ectoine are affected. In the A2058 cell line, but only TRP2 and MITF will be affected by Ectoine. We found protein expression of cells were decreased obviously with increasing concentration of ectoine.