Bar-Hanun Ester, Hanya Ester, Chiliveru Abhishiktha, Cahan Rivka
Department of Chemical Engineering, Ariel University, Ariel 40700, Israel.
Microorganisms. 2025 Aug 18;13(8):1925. doi: 10.3390/microorganisms13081925.
This study examined the membrane permeability of , which were exposed to a moderate pulsed electric field (PEF) (3.3 kV/cm). The membrane permeability of was examined as a function of time after exposure to PEF. When comparing the percentage of propidium iodide (PI) permeability at a given time from PEF exposure, it appeared that as the bacterial density increased, there was a decrease in PI permeability. The permeability to PI in the bacterial suspensions of 0.05, 0.1, and 0.5 OD, 90 min after exposure, was 56.4 ± 4.08%, 43.91 ± 0.75%, and 29.47 ± 3.31%, respectively. Membrane permeability was also examined in different phosphate-buffered saline (PBS) concentrations. At 0.05 OD there was a linear correlation between PBS concentrations (0.56, 0.75, and 1 mM) and PI permeability (28.36 ± 2.22%, 61.08 ± 3.17%, and 98.2 ± 0.9%, respectively). At the higher bacterial densities of 0.1 and 0.5 OD, this phenomenon was not evident. Examination of bacterial membrane permeability using 4, 70, and 250 kDa fluorescein isothiocyanate (FITC)-dextran revealed that PEF led to 4kDa FITC-dextran permeabilization of 27.94 ± 3.76%. The PEF parameters used did not influence the bacterial cell size and viability. This study shed light on bacterial membrane permeability as a function of conductivity and bacterial density under PEF exposure.
本研究检测了暴露于中等强度脉冲电场（PEF）（3.3 kV/cm）下的[具体对象未提及]的膜通透性。在暴露于PEF后，将[具体对象未提及]的膜通透性作为时间的函数进行检测。当比较从PEF暴露开始给定时间点碘化丙啶（PI）通透性的百分比时，发现随着细菌密度增加，PI通透性降低。暴露90分钟后，0.05、0.1和0.5 OD细菌悬液中对PI的通透性分别为56.4±4.08%、43.91±0.75%和29.47±3.31%。还在不同磷酸盐缓冲盐水（PBS）浓度下检测了膜通透性。在0.05 OD时，PBS浓度（0.56、0.75和1 mM）与PI通透性（分别为28.36±2.22%、61.08±3.17%和98.2±0.9%）之间存在线性相关性。在0.1和0.5 OD的较高细菌密度下，这种现象不明显。使用4、70和250 kDa异硫氰酸荧光素（FITC）-葡聚糖检测细菌膜通透性表明，PEF导致4 kDa FITC-葡聚糖的通透性为27.94±3.76%。所使用的PEF参数不影响细菌细胞大小和活力。本研究揭示了在PEF暴露下，细菌膜通透性作为电导率和细菌密度的函数关系。
