Yamauchi Kosei, Mitsunaga Tohru, Itakura Yuki, Batubara Irmanida
The United Graduate School of Agricultural Science, Gifu University, 1-1 Yanagido, 501-1193 Gifu, Japan.
The United Graduate School of Agricultural Science, Gifu University, 1-1 Yanagido, 501-1193 Gifu, Japan.
Fitoterapia. 2015 Jul;104:69-74. doi: 10.1016/j.fitote.2015.05.006. Epub 2015 May 12.
Ugonin J, K, and L, which are luteolin derivatives, were isolated from Helminthostachys zeylanica roots by a series of chromatographic separations of a 50% ethanol/water extract. They were identified using nuclear magnetic resonance (NMR), ultraviolet (UV) spectra, and ultra-performance liquid chromatography coupled to time-of-flight mass spectrometry (UPLC-TOF-MS). In this study, the intra and extracellular melanogenic activity of the ugonins were determined using B16 melanoma cells. The results showed that ugonin J at 12.5, 25, and 50μM reduced extracellular melanin contents to 75, 16, and 14%, respectively, compared to the control. This indicates that ugonin J showed a stronger activity than arbutin, used as the positive control. Moreover, ugonin K showed a more potent inhibition with 19, 8, and 9% extracellular melanin reduction at the same concentrations, than that shown by ugonin J. In contrast, ugonin L did not inhibit intra- or extracellular melanogenic activity. Furthermore, in order to investigate the structure-activity relationships of the ugonins, the intra- and extracellular melanogenic activity of luteolin, methylluteolin, quercetin, eriodictyol, apigenin, and chrysin were determined. Consequently, it was suggested that the catechol and flavone skeleton of ugonin K is essential for the extracellular melanogenic inhibitory activity, and the low polarity substituent groups on the A ring of ugonin K may increase the activity.
乌冈宁 J、K 和 L 是木犀草素衍生物，通过对 50%乙醇/水提取物进行一系列色谱分离，从锡兰莲座蕨根中分离得到。利用核磁共振（NMR）、紫外（UV）光谱以及超高效液相色谱-飞行时间质谱联用（UPLC-TOF-MS）对它们进行了鉴定。在本研究中，使用 B16 黑色素瘤细胞测定了乌冈宁的细胞内和细胞外黑色素生成活性。结果表明，与对照组相比，12.5、25 和 50μM 的乌冈宁 J 分别将细胞外黑色素含量降低至 75%、16%和 14%。这表明乌冈宁 J 表现出比用作阳性对照的熊果苷更强的活性。此外，在相同浓度下，乌冈宁 K 对细胞外黑色素的抑制作用更强，分别降低了 19%、8%和 9%，优于乌冈宁 J。相比之下，乌冈宁 L 并未抑制细胞内或细胞外的黑色素生成活性。此外，为了研究乌冈宁的构效关系，测定了木犀草素、甲基木犀草素、槲皮素、圣草酚、芹菜素和白杨素的细胞内和细胞外黑色素生成活性。结果表明，乌冈宁 K 的邻苯二酚和黄酮骨架对于细胞外黑色素生成抑制活性至关重要，且乌冈宁 K 的 A 环上的低极性取代基可能会增强该活性。
