Polyphenolic Constituents of Cynomorium songaricum Rupr. and Antibacterial Effect of Polymeric Proanthocyanidin on Methicillin-Resistant Staphylococcus aureus
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- 作者：Shangwu Jin ; Eerdunbayaer ; Airi Doi ; Teruo Kuroda ; Guixia Zhang ; Tsutomu Hatano ; Guilin Chen
- 刊名：Journal of Agricultural and Food Chemistry
- 出版年：2012
- 出版时间：July 25, 2012
- 年：2012
- 卷：60
- 期：29
- 页码：7297-7305
- 全文大小：370K
- 年卷期：v.60,no.29(July 25, 2012)
- ISSN：1520-5118
文摘
Oligomeric and polymeric flavan-3-ols were obtained by chromatographic fractionation of extracts from Cynomorium songaricum Rupr. The structure of the polymeric constituent, cynomoriitannin, was characterized using spectral and chemical data. Results from acid-catalyzed degradation indicated that cynomoriitannin is a polymeric proanthocyanidin predominantly composed of epicatechin, together with low proportions of epicatechin-3-O-gallate and catechin as extension units. The terminal unit was chiefly composed of catechin, with an admixture of epicatechin. Size exclusion chromatographic analysis demonstrated a mean polymerization degree of 14. Two new phloroglucinol adducts (cynomoriitannin-phloroglucinol adducts A and B) obtained by acid-catalyzed degradation of cynomoriitannin in the presence of phloroglucinol were characterized using spectral analyses. Six oligomeric flavan-3-ols were also identified as follows: procyanidin B3, catechin-(6鈥?8)-catechin, catechin-(6鈥?6)-catechin, epicatechin-(4尾-8)- epicatechin-(4尾-8)-catechin, epicatechin-(4尾-6)-epicatechin-(4尾-8)-catechin, and arecatannin A1, respectively. These flavan-3-ols were isolated from C. songaricum. This is the first time that this procedure has been described. The antibacterial activity of the fractions and constituents was tested against methicillin-resistant Staphylococcus aureus (MRSA). The crude acetone鈥搘ater (7:3) extract had moderate activity against MRSA. Cynomoriitannin was the most effective of the plant constituents against MRSA.