Environmental Biotechnology Cooperative Research Centre, School of Veterinary and Biomedical Sciences, Murdoch University, Murdoch, WA, Australia.
J Appl Microbiol. 2010 Jun;108(6):2222-8. doi: 10.1111/j.1365-2672.2009.04630.x. Epub 2009 Nov 18.
To compare the susceptibility of a 3-day-old biofilm and planktonic Salmonella to disinfectants at different exposure times. We hypothesize that Salmonella biofilms are more resilient to disinfectants compared to planktonic Salmonella.
The susceptibility of planktonic cells to disinfectants was tested by a modified version of the Council of Europe suspension test EN 1276. Salmonella biofilms were formed using the Calgary Biofilm Device. Results show that 3-day-old Salmonella biofilms are less susceptible to the disinfectants benzalkonium chloride, chlorhexidine gluconate, citric acid, quaternary ammonium compounds, sodium hypochlorite (SH) and ethanol, compared to planktonic Salmonella. Surprisingly, the results also demonstrate that low concentrations of SH were more effective against a 3-day-old biofilm compared to high concentrations of SH.
While all the disinfectants evaluated were able to reduce biofilm-associated cells at concentrations and contact times sufficient to eliminate planktonic cells, there were still sufficient viable cells remaining in the biofilm to cause further contamination and potential infection.
Protocols for the use of chemical disinfectants need to include biofilm susceptibility testing. There is a requirement for an effective and standardized tool for determining the susceptibility of biofilms to disinfectants.
比较 3 日龄生物膜和浮游态沙门氏菌对不同暴露时间消毒剂的敏感性。我们假设与浮游态沙门氏菌相比，生物膜中的沙门氏菌对消毒剂有更强的抵抗力。
通过对欧洲理事会悬浮试验 EN 1276 的修改版本，测试了浮游细胞对消毒剂的敏感性。使用卡尔加里生物膜装置形成沙门氏菌生物膜。结果表明，与浮游态沙门氏菌相比，3 日龄沙门氏菌生物膜对苯扎氯铵、葡萄糖酸氯己定、柠檬酸、季铵化合物、次氯酸钠（SH）和乙醇等消毒剂的敏感性较低。令人惊讶的是，结果还表明，与高浓度 SH 相比，低浓度 SH 对 3 日龄生物膜更有效。
虽然所有评估的消毒剂都能够在足以消灭浮游细胞的浓度和接触时间下减少生物膜相关细胞，但生物膜中仍有足够的存活细胞残留，从而导致进一步的污染和潜在感染。
化学消毒剂使用的方案需要包括生物膜敏感性测试。需要一种有效和标准化的工具来确定生物膜对消毒剂的敏感性。
