Center for Biofilm Engineering, Montana State University, Bozeman, MT, USA Microbion Corporation, Bozeman, MT, USA.
J Appl Microbiol. 2011 Oct;111(4):989-96. doi: 10.1111/j.1365-2672.2011.05110.x. Epub 2011 Aug 5.
The purpose of this study was to evaluate the antimicrobial efficacy of thirteen bismuth thiol preparations for bactericidal activity against established biofilms formed by two bacteria isolated from human chronic wounds.
Single species biofilms of a Pseudomonas aeruginosa or a methicillin-resistant Staphylococcus aureus were grown in either colony biofilm or drip-flow reactors systems. Biofilms were challenged with bismuth thiols, antibiotics or silver sulfadiazine, and log reductions were determined by plating for colony formation.
Antibiotics were ineffective or inconsistent against biofilms of both bacterial species tested. None of the antibiotics tested were able to achieve >2 log reductions in both biofilm models. The 13 different bismuth thiols tested in this investigation achieved widely varying degrees of killing, even against the same micro-organism in the same biofilm model. For each micro-organism, the best bismuth thiol easily outperformed the best conventional antibiotic. Against P. aeruginosa biofilms, bismuth-2,3-dimercaptopropanol (BisBAL) at 40-80 μg ml⁻¹ achieved > 7·7 mean log reduction for the two biofilm models. Against MRSA biofilms, bismuth-1,3-propanedithiol/bismuth-2-mercaptopyridine N-oxide (BisBDT/PYR) achieved a 4·9 log reduction.
Bismuth thiols are effective antimicrobial agents against biofilms formed by wound bacteria and merit further development as topical antiseptics for the suppression of biofilms in chronic wounds.
本研究旨在评估 13 种含铋硫醇制剂对两种从慢性人伤口分离得到的细菌形成的已建立生物膜的杀菌活性。
采用菌落生物膜或滴流反应器系统，分别培养铜绿假单胞菌或耐甲氧西林金黄色葡萄球菌的单种生物膜。用含铋硫醇、抗生素或磺胺嘧啶银处理生物膜，并通过平板菌落形成进行检测以确定对数减少。
抗生素对两种受试细菌的生物膜均无效或效果不一致。在两种生物膜模型中，没有一种抗生素能达到>2 个对数减少。在本研究中测试的 13 种不同的含铋硫醇表现出广泛不同的杀菌效果，即使是针对相同生物膜模型中的相同微生物。对于每种微生物，最好的含铋硫醇很容易优于最好的常规抗生素。对于铜绿假单胞菌生物膜，40-80μgml⁻¹的二巯基丁二酸（BisBAL）在两种生物膜模型中达到了>7·7 个平均对数减少。对于耐甲氧西林金黄色葡萄球菌生物膜，1,3-丙二硫醇/1,3-丙二硫醇/2-巯基吡啶 N-氧化物（BisBDT/PYR）达到了 4.9 个对数减少。
含铋硫醇是针对伤口细菌形成的生物膜的有效抗菌剂，值得进一步开发作为局部防腐剂，以抑制慢性伤口中的生物膜。
