Département de Biologie, Faculté des Sciences, Université Abdelmalek Essaâdi, Tétouan, Morocco.
J Appl Microbiol. 2010 Oct;109(4):1139-49. doi: 10.1111/j.1365-2672.2010.04740.x. Epub 2010 Aug 19.
To study cellular damage induced by Cinnamomum verum essential oil in Pseudomonas aeruginosa ATCC 27853 and Staphylococcus aureus ATCC 29213.
The effect of cinnamon bark essential oil on these two strains was evaluated by plate counts, potassium leakage, flow cytometry and transmission electron microscopy (TEM). Exposure to this oil induced alterations in the bacterial membrane of Ps. aeruginosa, which led to the collapse of membrane potential, as demonstrated by bis-oxonol staining, and loss of membrane-selective permeability, as indicated by efflux of K(+) and propidium iodide accumulation. Thus, respiratory activity was inhibited, leading to cell death. In Staph. aureus, cells treated with the oil entered a viable but noncultivable (VNC) state. The oil initially caused a considerable decrease in the metabolic activity and in the replication capacity of these bacterial cells. The loss of membrane integrity appeared later, as indicated by bis-oxonol and Propidium iodide (PI) staining. Data provided by TEM showed various structural effects in response to cinnamon essential oil. In Ps. aeruginosa cells, coagulated cytoplasmic material was observed, and intracellular material was seen in the surrounding environment, while oil-treated Staph. aureus showed fibres extending from the cell surface.
Cinnamon essential oil damages the cellular membrane of Ps. aeruginosa, which leads to cell death. There is evidence of VNC Staph. aureus after exposure to the oil.
Cinnamon essential oil shows effective antimicrobial activity and health benefits and is therefore considered a potential food additive. To use this oil as a natural food preservative, especially in combination with other preservation methods, a thorough understanding of the mechanism through which this oil exerts its antibacterial action is required.
研究肉桂精油对铜绿假单胞菌 ATCC 27853 和金黄色葡萄球菌 ATCC 29213 的细胞损伤作用。
通过平板计数、钾泄漏、流式细胞术和透射电子显微镜（TEM）评估肉桂树皮精油对这两种菌株的影响。暴露于该油会导致铜绿假单胞菌的细菌膜发生改变，导致膜电位崩溃，如双氧化诺尔染色所示，并丧失膜选择性通透性，如 K(+)外溢和碘化丙啶积累所示。因此，呼吸活性受到抑制，导致细胞死亡。在金黄色葡萄球菌中，用油处理的细胞进入存活但不可培养（VNC）状态。该油最初会导致这些细菌细胞的代谢活性和复制能力大幅下降。随后，膜完整性丧失，如双氧化诺尔和碘化丙啶（PI）染色所示。TEM 提供的数据显示，肉桂精油对细胞产生了各种结构影响。在铜绿假单胞菌细胞中，观察到凝结的细胞质物质，并且在周围环境中观察到细胞内物质，而用油处理的金黄色葡萄球菌显示出从细胞表面延伸的纤维。
肉桂精油会损伤铜绿假单胞菌的细胞膜，导致细胞死亡。金黄色葡萄球菌暴露于油后存在 VNC 的证据。
肉桂精油具有有效的抗菌活性和健康益处，因此被认为是一种潜在的食品添加剂。为了将这种油用作天然食品防腐剂，特别是与其他保存方法结合使用，需要深入了解这种油发挥其抗菌作用的机制。
