| 摘要: | 近年來，台灣柑橘類水果生產過剩導致農業廢棄物之增加，我們試圖找到這些潛在的有價值的廢物的使用，評估柚皮(Citrus grandis Osbeck)的抗氧化功效。柚皮用95%乙醇提取後，再以不同極性的有機溶媒分配萃取，分別得到正己烷層、95 %甲醇層、正丁醇層及水層四部分。其中95 %甲醇層顯示較強的DPPH自由基清除活性、清除ABTS·+自由基清除作用、抑制脂氧合酶作用、螯合亞鐵離子作用及抑制酪胺酸酶的作用。正己烷層和95 %甲醇層部分進一步利用矽膠層析和Sephadex LH-20純化分離。共分離出8個純化合物。Flavonoids類：Naringin (1，582.2 mg)；Triterpenes類：Limonin (2，356.6 mg) ；Coumarin類 ：Meranzin hydrate (3，2.86 g)、Isoimperatorin (5，179.8 mg) 及Bergaptol (7，119.2 mg)；Steroids類：-Sitosterol (4，177.9 mg)、Stigmasterol (6，427.9 mg)及-Sitosterol-D-glucoside (8，114.6 mg)，以上的化合物利用各種光譜鑑定其化學結構。 柚皮之有效成分具DPPH自由基清除活性的化合物7為56.3%，具有清除ABTS·+自由基活性的化合物2及7分別有100.6%及61.3%，具有抑制脂氧合酶作用之化合物2、5及7分別為98.5%、100.0%及93.9%。化合物1、2及3有明顯對酪胺酸酶之抑制作用。故柚皮之有效成分可作為皮膚美白、抗老化及抗發炎化妝產品之開發。
In recent years, the overproduction of citrus fruits has resulted in an unnecessary increase in agricultural wastes in Taiwan. In an attempt to find an application for these potentially valuable wastes, we evaluated the antioxidant and whitening properties of Citrus grandis Osbeck. The ethanolic extract, 95% MeOH fractions from dried C. grandis peel revealed strong 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging activity. Inhibition of ABTS, inhibition LOX activity, Chelating effect and tyrosinase inhibition.The n-hexane and 95% MeOH layer were purified by a combination of silica gel chromatography and Sephadex LH-20. Eight compounds were isolated, where Naringin (1, 582.2 mg), Limonin (2, 356.6 mg), Meranzin hydrate (3, 2.86 g), -Sitosterol (4, 177.9 mg), Isoimperatorin (5, 179.8 mg), Stigmasterol (6, 427.9 mg), Bergaptol (7，119.2 mg), -Sitosterol-D-glucoside (8, 114.6 mg). Their structures were established on the basis of spectral evidence.From Citrus grandis Osbeck was isolated compound 7 showed DPPH scanvenging activity and compounds 2 and 7 showed inhibition of ABTS activity and compounds 2, 5 and 7 showed inhibition of LOX activity. The compounds 1, 2 and 3 were confirmed to inhibit tyrosinase. |
