title: Antioxidant properties of two gallotannins isolated from the leaves of Pistacia weinmannifolia.
abstract: 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.
authors.affiliation: Center for Structural and Molecular Biology, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China.
authors.forename: Xingyu
authors.initials: X
authors.lastname: Zhao
authors.forename: Handong
authors.initials: H
authors.lastname: Sun
authors.forename: Aijun
authors.initials: A
authors.lastname: Hou
authors.forename: Qinshi
authors.initials: Q
authors.lastname: Zhao
authors.forename: Taotao
authors.initials: T
authors.lastname: Wei
authors.forename: Wenjuan
authors.initials: W
authors.lastname: Xin
mesh_terms: D000975:Antioxidants / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology*; D004247:DNA / Q000737:chemistry; D004365:Drugs, Chinese Herbal / Q000737:chemistry; D005609:Free Radicals / Q000737:chemistry; D047348:Hydrolyzable Tannins / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology*; D015227:Lipid Peroxidation / Q000187:drug effects; D015394:Molecular Structure; D010084:Oxidation-Reduction / Q000187:drug effects; D018384:Oxidative Stress / Q000187:drug effects; D027927:Pistacia / Q000737:chemistry*; D018515:Plant Leaves / Q000737:chemistry*
chemical_list: D000975:Antioxidants; D004365:Drugs, Chinese Herbal; D005609:Free Radicals; D047348:Hydrolyzable Tannins; C454980:pistafolia A; D004247:DNA