Khan M S A, Zahin M, Hasan S, Husain F M, Ahmad I
Department of Agricultural Microbiology, Faculty of Agricultural Sciences, Aligarh Muslim University, Aligarh, India.
Lett Appl Microbiol. 2009 Sep;49(3):354-60. doi: 10.1111/j.1472-765X.2009.02666.x. Epub 2009 Jul 14.
To evaluate quorum sensing (QS) inhibitory activity of plant essential oils using strains of Chromobacterium violaceum (CV12472 and CVO26) and Pseudomonas aeruginosa (PAO1).
Inhibition of QS-controlled violacein production in C. violaceum was assayed using disc diffusion and agar well diffusion method. Of the 21 essential oils, four oils showed varying levels of anti-QS activity. Syzygium aromaticum (Clove) oil showed promising anti-QS activity on both wild and mutant strains with zones of pigment inhibition 19 and 17 mm, respectively, followed by activity in cinnamon, lavender and peppermint oils. The effect of clove oil on the extent of violacein production was estimated photometrically and found to be concentration dependent. At sub-MICs of clove oil, 78.4% reduction in violacein production over control and up to 78% reduction in swarming motility in PAO1 over control were recorded. Gas chromatography-mass spectrometry analysis of clove oil indicated presence of many phytocompounds. Eugenol, the major constituent of clove oil could not exhibit anti-QS activity.
Presence of anti-QS activity in clove oil and other essential oils has indicated new anti-infective activity. The identification of anti-QS phytoconstituents is needed to assess the mechanism of action against both C. violaceum and Ps. aeruginosa.
Essential oils having new antipathogenic drugs principle because of its anti-QS activity might be important in reducing virulence and pathogenicity of drug-resistant bacteria in vivo.
使用紫色色杆菌（CV12472和CVO26）菌株以及铜绿假单胞菌（PAO1）评估植物精油的群体感应（QS）抑制活性。
采用纸片扩散法和琼脂孔扩散法检测紫色色杆菌中群体感应控制的紫菌素产生的抑制情况。在21种精油中，有4种精油表现出不同程度的抗群体感应活性。丁香精油对野生型和突变型菌株均显示出有前景的抗群体感应活性，色素抑制圈分别为19毫米和17毫米，其次是肉桂、薰衣草和薄荷精油有活性。通过光度法评估丁香精油对紫菌素产生程度的影响，发现其具有浓度依赖性。在丁香精油的亚最小抑菌浓度下，紫菌素产生量比对照降低了78.4%，PAO1的群体运动性比对照降低了78%。丁香精油的气相色谱 - 质谱分析表明存在许多植物化合物。丁香精油的主要成分丁香酚未表现出抗群体感应活性。
丁香精油和其他精油中存在抗群体感应活性表明了新的抗感染活性。需要鉴定抗群体感应植物成分以评估其对紫色色杆菌和铜绿假单胞菌的作用机制。
具有新的抗致病药物原理的精油因其抗群体感应活性可能在降低体内耐药细菌的毒力和致病性方面具有重要意义。
