He, T-FZhang, Z-HZeng, X-AWang, L-HBrennan, CS2018-08-072017-11-102018-012017-11-09He, T-F., Zhang, Z-H., Zeng, X-A, Wang, L-H., & Brennan, C.S. (2017). Determination of membrane disruption and genomic DNA binding of cinnamaldehyde to Escherichia coli by use of microbiological and spectroscopic techniques. Journal of Photochemistry and Photobiology, B: Biology, 178, 623-630. doi:10.1016/j.jphotobiol.2017.11.0151011-134429306845 (pubmed)https://hdl.handle.net/10182/10122This work was aimed to investigate the antibacterial action of cinnamaldehyde (CIN) against Escherichia coli ATCC 8735 (E. coli) based on membrane fatty acid composition analysis, alterations of permeability and cell morphology as well as interaction with genomic DNA. Analysis of membrane fatty acids using gas chromatography-mass spectrometry (GC-MS) revealed that the proportion of unsaturated fatty acids (UFA) and saturated fatty acids (SFA) were the major fatty acids in plasmic membrane, and their levels were significantly changed after exposure of E. coli to CIN at low concentrations. For example, the proportion of UFA decreased from 39.97% to 20.98%, while the relative content of SFA increased from 50.14% to 67.80% as E. coli was grown in increasing concentrations of CIN (from 0 to 0.88mM). Scanning electron microscopy (SEM) showed that the morphology of E. coli cells to be wrinkled, distorted and even lysed after exposure to CIN, which therefore decreased the cell viability. The binding of CIN to genomic DNA was probed using fluorescence, UV-Visible absorption spectra, circular dichroism, molecular modeling and atomic force microscopy (AFM). Results indicated that CIN likely bound to the minor groove of genomic DNA, and changed the secondary structure and morphology of this biomacromolecule. Therefore, CIN can be deem as a kind of natural antimicrobial agents, which influence both cell membrane and genomic DNA.pp.623-630Print-Electroniceng© 2017 Elsevier B.V. All rights reserved.cinnamaldehydeEscherichia colimembrane fatty acidgenomic DNACell WallEscherichia coliAcroleinFatty AcidsFatty Acids, UnsaturatedDNAAnti-Bacterial AgentsMicroscopy, Electron, ScanningMicroscopy, Atomic ForceSpectrophotometry, UltravioletCircular DichroismBinding SitesNucleic Acid ConformationGas Chromatography-Mass SpectrometryMolecular Docking SimulationJournal Article10.1016/j.jphotobiol.2017.11.015ANZSRC::0908 Food Sciences1873-2682ANZSRC::3406 Physical chemistry