Polyphenolic Constituents of Cynomorium songaricum Rupr. and Antibacterial Effect of Polymeric Proanthocyanidin on Methicillin-Resistant Staphylococcus aureus

• Published in: Journal of agricultural and food chemistry Vol. 60; no. 29; pp. 7297 - 7305
• Main Authors: Jin, Shangwu, Eerdunbayaer, Doi, Airi, Kuroda, Teruo, Zhang, Guixia, Hatano, Tsutomu, Chen, Guilin
• Format: Journal Article
• Language: English
• Published: United States American Chemical Society 25-07-2012
• Subjects: Anti-Bacterial Agents - pharmacology; antibacterial properties; catechin; Catechin - chemistry; Cynomorium - chemistry; epicatechin; Flavonoids - analysis; Flavonoids - chemistry; fractionation; Methicillin-Resistant Staphylococcus aureus - drug effects; Phloroglucinol - chemistry; Plant Extracts - chemistry; Plant Extracts - pharmacology; Plant Stems - chemistry; polymerization; Polyphenols - analysis; Proanthocyanidins - chemistry; Proanthocyanidins - pharmacology; size exclusion chromatography; spectral analysis; Staphylococcus aureus; phloroglucinol adducts; antibacterial effect; methicillin-resistant Staphylococcus aureus; proanthocyanidin; Cynomorium songaricum Rupr
• ISSN: 0021-8561; 1520-5118
• DOI: 10.1021/jf301621e

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′-8)-catechin, catechin-(6′-6)-catechin, epicatechin-(4β-8)- epicatechin-(4β-8)-catechin, epicatechin-(4β-6)-epicatechin-(4β-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–water (7:3) extract had moderate activity against MRSA. Cynomoriitannin was the most effective of the plant constituents against MRSA.