title: Antibacterial Activity and Membrane-Disruptive Mechanism of 3-p-trans-Coumaroyl-2-hydroxyquinic Acid, a Novel Phenolic Compound from Pine Needles of Cedrus deodara, against Staphylococcus aureus.
abstract: Recently, we reported that a novel phenolic compound isolated from Cedrus deodara, 3-p-trans-coumaroyl-2-hydroxyquinic acid (CHQA), exhibits a potent antioxidant activity. The present study aimed to evaluate the antibacterial activity of CHQA against eleven food-borne pathogens and to elucidate its mechanism of action against Staphylococcus aureus. The results from minimum inhibitory concentration (MIC) determinations showed that CHQA exhibited moderate inhibitory effects on all of the tested pathogens with MIC values ranging from 2.5-10 mg/mL. Membrane potential measurements and flow cytometric analysis demonstrated that CHQA damaged the cytoplasmic membrane of S. aureus, causing a significant membrane hyperpolarization with a loss of membrane integrity. Moreover, CHQA induced an increase in membrane fluidity and conformational changes in membrane protein of S. aureus, suggesting that CHQA probably acts on the cell membrane by interactions with membrane lipid and protein. Transmission electron microscopic observations further confirmed that CHQA disrupted the cell membrane of S. aureus and caused severe morphological changes, which even led to leakage of intracellular constituents. These findings indicated that CHQA could have the potential to serve as a natural antibacterial agent to control and prevent the growth of pathogens in food and in food-processing environments.
authors.affiliation: Department of Food Science and Technology, College of Light Industry, Textile and Food Engineering, Sichuan University, Chengdu 610065, China. wyp9202@163.com.
authors.forename: Yanping
authors.initials: Y
authors.lastname: Wu
authors.affiliation: Department of Food Science and Technology, College of Light Industry, Textile and Food Engineering, Sichuan University, Chengdu 610065, China. baijinrong01@hotmail.com.
authors.forename: Jinrong
authors.initials: J
authors.lastname: Bai
authors.affiliation: Department of Food Science and Technology, College of Light Industry, Textile and Food Engineering, Sichuan University, Chengdu 610065, China. eric211@163.com.
authors.forename: Kai
authors.initials: K
authors.lastname: Zhong
authors.affiliation: Department of Public Health, West China Medical School, Sichuan University, Chengdu 610041, China. dir0932@sina.com.
authors.forename: Yina
authors.initials: Y
authors.lastname: Huang
authors.affiliation: Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu 610041, China. qihy@cib.ac.cn.
authors.forename: Huayi
authors.initials: H
authors.lastname: Qi
authors.affiliation: Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu 610041, China. jiangyan@cib.ac.cn.
authors.forename: Yan
authors.initials: Y
authors.lastname: Jiang
authors.affiliation: Department of Food Science and Technology, College of Light Industry, Textile and Food Engineering, Sichuan University, Chengdu 610065, China. gao523@hotmail.com.
authors.forename: Hong
authors.initials: H
authors.lastname: Gao
mesh_terms: D000900:Anti-Bacterial Agents / Q000737:chemistry / Q000494:pharmacology*; D028203:Cedrus / Q000737:chemistry*; D002462:Cell Membrane / Q000187:drug effects; D008564:Membrane Potentials; D008826:Microbial Sensitivity Tests; D015394:Molecular Structure; D010636:Phenols / Q000737:chemistry / Q000494:pharmacology*; D010936:Plant Extracts / Q000737:chemistry / Q000494:pharmacology; D013211:Staphylococcus aureus / Q000187:drug effects*
chemical_list: D000900:Anti-Bacterial Agents; D010636:Phenols; D010936:Plant Extracts
keywords: Staphylococcus aureus; antibacterial activity; antibacterial mechanism; membrane damage; phenolic compound