致病微生物污染引起的食源性疾病是世界上最突出的食品卫生问题，这也是当前我国食品质量安全急需解决的重大问题。本项目拟以雪松松针为切入点，将着重探讨其中新型抗菌剂3-香豆酰-2-羟基奎尼酸（CHQA）对食源性致病菌金黄色葡萄球菌抑制及有害毒素分泌调控的可能分子机制。通过抑菌活性及构效关系的研究，解明CHQA的分子结构特征与抑菌作用的相互关系；分析 CHQA对细胞膜正常生理功能损伤的影响，深入探讨CHQA对细胞代谢活性的影响，阐明CHQA对金黄色葡萄球菌细胞功能的影响及其作用机理；分析CHQA对金黄色葡萄球菌肠毒素A和a-毒素分泌的影响，深入探讨相关调控基因表达的水平，同时研究CHQA对金黄色葡萄球菌生物被膜形成的影响，验证CHQA是否通过减弱细菌致病性途径而达到抑菌效果。本项目的顺利完成将为进一步研究雪松松针对食源性致病菌的控制提供实验依据和参考方法，为食源性致病菌抑制剂的研制提供新靶点。

Foodborne diseases are a growing public health problem worldwide. The main reason is due to ingestion of foodstuffs contaminated with microorganisms and the contamination of food may occur at any stage in the process from food production to consumption (“farm to fork”). Currently, this is also a major problem in urgent need of food quality and safety in China. In the present study, we will investigate the antimicrobial effect and molecular mechanism of a novel antibacterial agent of 3-coumaroyl-2-hydroxyquinic acid (CHQA) from Cedrus deodara pine needle on foodborne pathogenic bacteria. Especially, we will carry out investigating the inhibitory effects and molecular mechanism of action of CHQA on the biological activity and production of bacterial toxins of Staphylococcus aureus. Firstly, the structure-activity relation (SAR) study will be developed to disclose the effect of the chemical structural characterization of CHQA on antibacterial activity. Next, we will draw to investigate the effects of CHQA on cell membranes and cell metabolic activity and elucidate the mode of action of CHQA on cell functions of Staphylococcus aureus. Finally, we will investigate the effects of CHQA on the productions of Staphylococcal enterotoxin A and -toxins, the expressions of the relative genes and biofilm production, and verify whether CHQA could exhibit antibacterial effect through weakening pathogenic pathway of Staphylococcus aureus. The successful completion of this project will supply experimental data and reference methods, will help develop new strategies for controlling foodborne pathogenic bacteria, and is very valuable for the comprehensive utilizations of C. deodara pine needle.