Citrus essential oils are used in food to confer flavor and aromas. The citrus essential oils have been granted as GRAS and could be used as antimicrobial additives to control bacterial quorum sensing from potential food bacterial pathogens. The chemical composition and inhibitory activity of Citrus paradisi (grapefruit) essential oils obtained by cold-pressed method (EOP) and cold-pressed method followed by steam distillation, against Pseudomonas aeruginosa were determined. The GC-MS analyses of the oil indicated the amount of the essential oil components was highest with D-limonene in both cases. However, the extraction method modified the chemical composition. EOP had higher amount of coumarins and flavonoid as well as less oxygenated terpenoids. At 0.1 mg/mL essential oils were not able to modify the bacterial development but inhibited the P. aeruginosa biofilm production between 52% and 55%, sessile viability between 45% and 48%, autoinducer production and elastase activity between 30% and 56%. Limonene was less effective at inhibiting P. aeruginosa than the essential oils, suggesting a synergistic effect of the minor components. According to our results, grapefruit essential oils could be used as a food preservative to control P. aeruginosa virulence.

中文翻译：

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葡萄柚精油抑制铜绿假单胞菌的群体感应

柑橘精油用于食品中以赋予风味和香气。柑橘精油已被授予 GRAS，可用作抗菌添加剂，以控制潜在食物细菌病原体的细菌群体感应。测定了通过冷压法 (EOP) 和冷压法随后蒸汽蒸馏获得的 Citrus paradisi (葡萄柚) 精油对铜绿假单胞菌的化学成分和抑制活性。油的 GC-MS 分析表明，在两种情况下，D-柠檬烯的精油成分含量最高。然而，提取方法改变了化学成分。EOP 具有较高量的香豆素和类黄酮以及较少的含氧萜类化合物。0.1 毫克/毫升的精油不能改变细菌的发育，但能抑制 P. 铜绿假单胞菌生物膜产量在 52% 和 55% 之间，固着活力在 45% 和 48% 之间，自诱导剂产量和弹性蛋白酶活性在 30% 和 56% 之间。柠檬烯在抑制铜绿假单胞菌方面的效果不如精油，表明微量成分具有协同作用。根据我们的研究结果，葡萄柚精油可用作食品防腐剂来控制铜绿假单胞菌的毒力。