R&D Center, AmorePacific Corporation, Kyounggi-do, Yongin, Republic of Korea.
Bioorg Med Chem Lett. 2010 Dec 15;20(24):7534-6. doi: 10.1016/j.bmcl.2010.09.082. Epub 2010 Oct 1.
The tyrosinase inhibitory activity of ethanolic extract of kenaf (Hibiscus cannabinus L.) leaf was evaluated before and after subjecting it to far-infrared (FIR) irradiation. The main component of the extract was analyzed as kaempferitrin (kaempferol-3,7-O-α-dirhamnoside). Prior to FIR irradiation, no inhibitory activity of the extract was detected in a tyrosinase assay. However, after FIR irradiation for 1h at 60°C, significant tyrosinase inhibitory activity (IC(50)=3500 ppm) was observed in it. In HPLC analysis, derhamnosylation products (kaempferol, afzelin, and α-rhamnoisorobin) were detected. The inhibitory activity may be due to the existence of derhamnosylation products. This study demonstrated that FIR irradiation can be used as a convenient tool for deglycosylation of flavonoid glycoside.
远红外（FIR）辐照前后苎麻（Hibiscus cannabinus L.）叶的乙醇提取物的酪氨酸酶抑制活性进行了评估。提取物的主要成分被分析为山柰酚-3,7-O-α-二鼠李糖苷（kaempferitrin）。在 FIR 辐照之前，在酪氨酸酶测定中未检测到提取物的抑制活性。然而，在 60°C 下进行 1 小时的 FIR 辐照后，观察到显著的酪氨酸酶抑制活性（IC（50）=3500ppm）。在 HPLC 分析中，检测到去鼠李糖苷化产物（山柰酚、afzelin 和 α-鼠李糖苷异芦丁）。抑制活性可能归因于去鼠李糖苷化产物的存在。本研究表明，FIR 辐照可用作黄酮糖苷去糖基化的便捷工具。
