Kaiser Stefan J, Mutters Nico T, Blessing Brigitte, Günther Frank
Heidelberg University Hospital, Department of Infectious Diseases, Germany.
Heidelberg University Hospital, Department of Infectious Diseases, Germany.
Fitoterapia. 2017 Jun;119:57-63. doi: 10.1016/j.fitote.2017.04.006. Epub 2017 Apr 5.
The antimicrobial properties of natural isothiocyanates (ITCs) found in plants such as nasturtium (Tropaeolum majus) and horseradish (Armoracia rusticana), and the need of new chemotherapeutic options for treatment of infections caused by multidrug-resistant and biofilm-forming Gram-negative bacteria such as Pseudomonas aeruginosa (Pa), led us to evaluate the effects of three major ITCs, allylisothiocyanate (AITC), benzylisothiocyanate (BITC), and phenylethyl-isothiocyanate (PEITC), and a mixture (ITCM) adapted to the ITC composition after release of active components out of natural sources.
MATERIAL/METHODS: Out of 105Pa isolates 27 isolates with increased biofilm formation were selected for testing. The effects of ITCs on Pa were evaluated regarding (1) planktonic bacterial proliferation, (2) biofilm formation, (3) metabolic activity in mature biofilms, and (4) synergism of ITCs and antibiotics.
(1) Each ITC had anti-Pa activity. Mean minimum inhibitory concentrations (MICs) were (μg/ml, mean±standard deviation): AITC 103±6.9; BITC, 2145±249; PEITC 29,423±1652; and ITCM, 140±5. (2) Treating bacteria with PEITC and ITCM in concentrations below the MIC significantly inhibited biofilm formation. Particularly, ITCM reduced biofilm mass and bacterial proliferation. (3) ITCs significantly inhibited metabolic activity in mature biofilms. (4) Combining ITCs with meropenem synergistically increased antimicrobial efficacy on Pa biofilms.
ITCs represent a promising group of natural anti-infective compounds with activity against Pa biofilms.
在旱金莲（Tropaeolum majus）和辣根（Armoracia rusticana）等植物中发现的天然异硫氰酸酯（ITC）具有抗菌特性，且由于需要新的化疗方案来治疗由多重耐药和形成生物膜的革兰氏阴性菌如铜绿假单胞菌（Pa）引起的感染，我们对三种主要的ITC，即烯丙基异硫氰酸酯（AITC）、苄基异硫氰酸酯（BITC）和苯乙基异硫氰酸酯（PEITC），以及一种从天然来源释放活性成分后根据ITC组成调配的混合物（ITCM）的效果进行了评估。
材料/方法：从105株Pa分离株中挑选出27株生物膜形成增加的分离株进行测试。评估了ITC对Pa的作用，包括（1）浮游细菌增殖，（2）生物膜形成，（3）成熟生物膜中的代谢活性，以及（4）ITC与抗生素的协同作用。
（1）每种ITC都具有抗Pa活性。平均最低抑菌浓度（MIC，μg/ml，平均值±标准差）为：AITC 103±6.9；BITC，2145±249；PEITC 29423±1652；ITCM，140±5。（2）用低于MIC浓度的PEITC和ITCM处理细菌可显著抑制生物膜形成。特别是，ITCM减少了生物膜量和细菌增殖。（3）ITC显著抑制成熟生物膜中的代谢活性。（4）将ITC与美罗培南联合使用可协同提高对Pa生物膜的抗菌效果。
ITC是一类有前景的天然抗感染化合物，对Pa生物膜具有活性。
