Ultee A, Gorris L G, Smid E J
Agrotechnological Research Institute (ATO-DLO), Wageningen, The Netherlands.
J Appl Microbiol. 1998 Aug;85(2):211-8. doi: 10.1046/j.1365-2672.1998.00467.x.
Carvacrol, a natural plant constituent occurring in oregano and thyme, was investigated for its bactericidal effect towards the food-borne pathogen Bacillus cereus. Carvacrol showed a dose-related growth inhibition of B. cereus. At concentration of 0.75 mmol l-1 and above, total inhibition of the growth was observed. Below this concentration, carvacrol extended the lag-phase, reduced the specific growth rate and reduced the maximum population density. Incubation for 40 min in the presence of 0.75-3 mmol l-1 carvacrol decreased the number of viable cells of B. cereus exponentially. Spores were found to be approximately 2-3 fold less sensitive to carvacrol than vegetative cells. Bacillus cereus cells showed reduced susceptibility towards carvacrol at pH 7.0 compared with different values between pH 4.5 and 8.5. The culture and exposure temperatures had a significant influence on the survival of vegetative cells. The highest death rate of cells was observed at an exposure temperature of 30 degrees C. Membrane fluidity was found to be an important factor influencing the bactericidal activity of carvacrol.
香芹酚是牛至和百里香中的一种天然植物成分，对食源性病原体蜡样芽孢杆菌的杀菌效果进行了研究。香芹酚对蜡样芽孢杆菌的生长抑制呈剂量相关。在0.75 mmol l-1及以上浓度时，观察到生长完全受到抑制。低于该浓度时，香芹酚延长了延迟期，降低了比生长速率并降低了最大种群密度。在0.75 - 3 mmol l-1香芹酚存在下孵育40分钟，蜡样芽孢杆菌的活细胞数量呈指数下降。发现芽孢对香芹酚的敏感性比营养细胞低约2 - 3倍。与pH 4.5至8.5之间的不同值相比，蜡样芽孢杆菌细胞在pH 7.0时对香芹酚的敏感性降低。培养温度和暴露温度对营养细胞的存活有显著影响。在30℃的暴露温度下观察到细胞的最高死亡率。发现膜流动性是影响香芹酚杀菌活性的一个重要因素。
