College of Food Science and Engineering, Northwest A&F University , Yangling, Shaanxi, China .
Foodborne Pathog Dis. 2014 Sep;11(9):677-83. doi: 10.1089/fpd.2013.1731. Epub 2014 Jun 6.
Chlorogenic acid (CA) has been reported to inhibit several pathogens, but the influence of subinhibitory concentrations of CA on virulence expression of pathogens has not been fully elucidated. The aim of this study was to explore the effect of CA on the virulence factor production of Staphylococcus aureus. The minimum inhibitory concentration (MIC) of CA against S. aureus was determined using a broth microdilution method. Hemolysin assays, coagulase titer assays, adherence to solid-phase fibrinogen assays, Western blot, and real-time reverse transcriptase-polymerase chain reaction were performed to evaluate the effect of subinhibitory concentrations of CA on the virulence factors of S. aureus. MIC of CA against S. aureus ATCC29213 was found to be 2.56 mg/mL. At subinhibitory concentrations, CA significantly inhibited the hemolysis and dose-dependently decreased coagulase titer. Reduced binding to fibrinogen and decreased production of SEA were observed with treatment of CA at concentrations ranging from 1/16MIC to 1/2MIC. CA markedly inhibited the expression of hla, sea, and agr genes in S. aureus. These data demonstrate that the virulence expression of S. aureus could be reduced by CA and suggest that CA could be potentially developed as a supplemental strategy to control S. aureus infection and to prevent staphylococcal food poisoning.
绿原酸 (CA) 已被报道能抑制多种病原体，但亚抑菌浓度的 CA 对病原体毒力表达的影响尚未完全阐明。本研究旨在探讨 CA 对金黄色葡萄球菌毒力因子产生的影响。采用肉汤微量稀释法测定 CA 对金黄色葡萄球菌的最小抑菌浓度 (MIC)。通过溶血试验、凝固酶滴度试验、固相纤维蛋白原黏附试验、Western blot 和实时逆转录聚合酶链反应评估亚抑菌浓度 CA 对金黄色葡萄球菌毒力因子的影响。发现 CA 对金黄色葡萄球菌 ATCC29213 的 MIC 为 2.56mg/mL。在亚抑菌浓度下，CA 显著抑制溶血，并呈剂量依赖性降低凝固酶滴度。用 CA 处理浓度范围为 1/16MIC 至 1/2MIC 时，观察到与纤维蛋白原结合减少和 SEA 产生减少。CA 显著抑制金黄色葡萄球菌 hla、sea 和 agr 基因的表达。这些数据表明 CA 可降低金黄色葡萄球菌的毒力表达，并提示 CA 可能被开发为控制金黄色葡萄球菌感染和预防葡萄球菌食物中毒的辅助策略。
