Lau Kit-Man, He Zhen-Dan, Dong Hui, Fung Kwok-Pui, But Paul Pui-Hay
Departments of Biology and Biochemistry, and Institute of Chinese Medicine, The Chinese University of Hong Kong, N T, Shatin, Hong .
J Ethnopharmacol. 2002 Nov;83(1-2):63-71. doi: 10.1016/s0378-8741(02)00192-7.
Aqueous extract of processed leaves of Ligustrum robustum could dose-dependently scavenge superoxide radicals, inhibit lipid peroxidation, and prevent AAPH-induced hemolysis of red blood cells. In comparison with green tea, oolong tea and black tea, processed leaves of L. robustum exhibited comparable antioxidant potency in scavenging superoxide radicals and in preventing red blood cell hemolysis. By activity-guided fractionation, a glycoside-rich fraction named fraction B2 was separated and demonstrated to possess strong antioxidant effect. It was evaluated for its anti-inflammatory and hepato-protective activities. A single oral dose of fraction B2 at 0.5 g/kg could provide 51.5% inhibition on the vascular permeability change induced by intraperitoneal injection of acetic acid, but it could not inhibit croton oil-induced ear edema. On the other hand, fraction B2 exhibited moderate hepato-protective effect. Intragastric application of fraction B2 at 1.25, 2.5 or 5 g/kg 6 h after carbon tetrachloride administration could reduce the elevations of serum levels of aminotransferases (AST and ALT). Also, liver integrity was preserved, as liver sections from rats post-treated with fraction B2 showed a milder degree of fatty accumulation and necrosis. These results offer partial support to the traditional uses of the leaves of L. robustum as Ku-Ding-Cha.
粗壮女贞加工叶的水提取物可剂量依赖性地清除超氧自由基、抑制脂质过氧化，并防止AAPH诱导的红细胞溶血。与绿茶、乌龙茶和红茶相比，粗壮女贞加工叶在清除超氧自由基和防止红细胞溶血方面表现出相当的抗氧化能力。通过活性导向分级分离，分离出一个名为B2级分的富含糖苷的级分，并证明其具有很强的抗氧化作用。对其抗炎和保肝活性进行了评估。单次口服0.5 g/kg的B2级分可对腹腔注射醋酸引起的血管通透性变化提供51.5%的抑制作用，但不能抑制巴豆油诱导的耳水肿。另一方面，B2级分表现出适度的保肝作用。在四氯化碳给药6小时后，以1.25、2.5或5 g/kg的剂量胃内给予B2级分可降低血清转氨酶（AST和ALT）水平的升高。此外，肝脏完整性得以保留，因为用B2级分后处理的大鼠肝脏切片显示脂肪堆积和坏死程度较轻。这些结果为粗壮女贞叶作为苦丁茶的传统用途提供了部分支持。
