Effects of Pulsed Electric Fields on Phospholipid Molecular Conformation by Raman Spectra
In order to study the sterilization mechanism of pulsed electric fields(PEF) on microorganisms and the interaction between PEF conditions and cell membrane composed of phospholipids, the authors studied the phospholipid molecular conformation changes under various electric fields strength treatments using Raman spectra. It was demonstrated from the Raman spectra that there was little influence of PEF on the conformation of O-C-C-N+ backbone in the choline group of phospholipid. The intensity ratios of I1096/I1062 and I1096/I1126 represented the gauche/ trans ratioof C-C vibrations, but the first was increased directly, while the other one was increased firstly and then decreased with increasing electric fields strengths but the ratio was still higher than that of the control sample. I2885/I2850 represeted order/ disorder of chain-chain interactions which was decreased with increasing electric fields strengths. It was indicated that the intermolecular disordering in hydrocarbon chain of the lipid lattice was increased and the membrane fluidity was enhanced after PEF treatments.