Zhao Xingyu, Sun Handong, Hou Aijun, Zhao Qinshi, Wei Taotao, Xin Wenjuan
Center for Structural and Molecular Biology, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China.
Biochim Biophys Acta. 2005 Aug 30;1725(1):103-10. doi: 10.1016/j.bbagen.2005.04.015.
Pistacia weinmannifolia J. Poisson ex Franch (Anacardiaceae) is a shrub or arbor widely found in Yunnan province of China and its leaves are used as traditional Chinese medicine by herbalists. The leaves of P. weinmannifolia are rich in phenolic compounds, among which two novel gallotannins, Pistafolin A and Pistafolin B, are identified. In the present investigation, the antioxidant efficiency of Pistafolin A and Pistafolin B in preventing lipid, protein and DNA from reactive oxygen species-mediated damage was studied. Both Pistafolin A and Pistafolin B inhibited the peroxyl-radical induced lipid peroxidation of l-alpha-phosphatidylcholine liposomes dose-dependently and prevented the bovine serum albumin from peroxyl-induced oxidative damage. Pistafolin A and Pistafolin B also inhibited copper (II)-1,10-phenanthroline complex-induced DNA oxidative damage. Both Pistafolin A and Pistafolin B scavenged the hydrophilic 2,2'-azinobis(3-ethylbenzothiozoline-6-sulphonic acid) diammonium salt-free radicals and the hydrophobic 1,1-dipheny-2-picrylhydrazyl radicals effectively, suggesting they may act as hydrogen donating antioxidants. The protective effects of the two gallotannins against oxidative damage of biomacromolecules were due to their strong free radical scavenging ability. Pistafolin A with three galloyl moieties showed stronger antioxidant ability than Pistafolin B with two galloyl moieties.
清香木（漆树科黄连木属）是一种灌木或乔木，在中国云南省广泛分布，其叶子被草药师用作传统中药。清香木叶富含酚类化合物，其中鉴定出两种新型没食子单宁，即清香木素A和清香木素B。在本研究中，研究了清香木素A和清香木素B在防止脂质、蛋白质和DNA受到活性氧介导损伤方面的抗氧化效率。清香木素A和清香木素B均剂量依赖性地抑制过氧自由基诱导的l-α-磷脂酰胆碱脂质体的脂质过氧化，并防止牛血清白蛋白受到过氧诱导的氧化损伤。清香木素A和清香木素B还抑制铜（II）-1,10-菲咯啉配合物诱导的DNA氧化损伤。清香木素A和清香木素B均能有效清除亲水性2,2'-偶氮双（3-乙基苯并噻唑啉-6-磺酸）二铵盐自由基和疏水性1,1-二苯基-2-苦基肼自由基，表明它们可能作为供氢抗氧化剂发挥作用。这两种没食子单宁对生物大分子氧化损伤的保护作用归因于它们强大的自由基清除能力。具有三个没食子酰基部分的清香木素A比具有两个没食子酰基部分的清香木素B表现出更强的抗氧化能力。
