Osland Ane Mohr, Vestby Lene K, Nesse Live L
Norwegian Veterinary Institute, Ullevålsvn 68, P.O. Box 750 Sentrum, 0106 Oslo, Norway.
Microorganisms. 2020 Nov 20;8(11):1831. doi: 10.3390/microorganisms8111831.
The aim of disinfection is to reduce the number of microorganisms on surfaces which is a challenge due to biofilms. In the present study, six quinolone resistant (QREC) strains with three different biofilm matrix compositions were included to assess the log colony forming units (CFU) reduction effect of three disinfectants at various exposure times on biofilm of different ages and morphotypes. Biofilm was formed on stainless steel coupons for two and five days before transferred to tubes with Virocid 0, 25%, VirkonS 1%, and TP990 1% and left for various exposure times. The biofilms were scraped off and serial dilutions were spread on blood agar plates where colony forming units (CFU) were counted. A mean log CFU reduction ≥4 was seen on two-day-old biofilm with VirkonS and Virocid (30 min) but not on five-day old biofilm. TP990 did not display sufficient effect under the conditions tested. The bactericidal effect was inferior to that reported on planktonic bacteria. The findings of this study should be considered when establishing both disinfectant routines and standard susceptibility tests, which further should accommodate biofilms and not only as is the case today.
消毒的目的是减少表面的微生物数量，而由于生物膜的存在，这是一项具有挑战性的任务。在本研究中，纳入了六种具有三种不同生物膜基质组成的喹诺酮耐药（QREC）菌株，以评估三种消毒剂在不同暴露时间对不同年龄和形态型生物膜的对数菌落形成单位（CFU）减少效果。生物膜在不锈钢试片上形成两天和五天，然后转移到含有0、25%的Virocid、1%的VirkonS和1%的TP990的试管中，并放置不同的暴露时间。将生物膜刮下并进行系列稀释，然后涂布在血琼脂平板上，计数菌落形成单位（CFU）。使用VirkonS和Virocid（30分钟）时，在两天龄的生物膜上观察到平均对数CFU减少≥4，但在五天龄的生物膜上未观察到。在测试条件下，TP990没有显示出足够的效果。其杀菌效果低于对浮游细菌的报道效果。在制定消毒程序和标准药敏试验时应考虑本研究的结果，而且这些程序应进一步适应生物膜，而不仅仅像目前这样。
