Mohamed SH, Mohamed MSM, Khalil MS, Azmy M, Mabrouk MI
Journal of Applied Microbiology, 2018
AIM: This study aimed to test biofilm inhibition activities of each of essential oils (EOs), main compounds of EOs and enzymes against pathogenic Klebsiella pneumonia.
METHODS AND RESULTS: Effect of seven EOs and three enzymes was tested on formation and eradication of Klebsiella pneumoniae biofilm. Peppermint oil showed robust biofilm inhibitory effect, causing inhibition ranged from 69.2-98.2% at 5 μl ml-1 . Thyme oil was found to have the best biofilm-eradication ability, causing eradication ranged from 80.1-98.0% at 10 μl ml-1 . The most effective EOs were analyzed by GC/MS, to determine the major chemical constitutes of each oil. Pure menthol was found to cause 75.3-97.5% biofilm-inhibition at 2.5 μg ml-1 whereas, thymol caused 85.1-97.8% biofilm eradication at 5 μg ml-1 . However, moderate inhibition activity was detected for α-amylase and bromelain, while poor activity was detected for β-amylase. Ciprofloxacin combination with thyme oil and thymol was found to enhance antibiotic activity, and affect biofilm cells viability. The observed inhibitory/eradication activity on Klebsiella pneumoniae biofilms was confirmed by scanning electron microscopy (SEM)
CONCLUSIONS: Thyme and peppermint EOs, and their active components are promising antibiofilm agents alone and/or in combination with ciprofloxacin to inhibit/eradicate biofilms of Klebsiella pneumoniae.
SIGNIFICANCE AND IMPACT OF THE STUDY: The presented results suggest potential application of EOs against infections, caused by biofilm-producing Klebsiella pneumoniae, to prevent biofilms formation or decrease their resistance threshold. Moreover, the combination of EOs with ciprofloxacin minimizes the antibiotic concentration used and accordingly the potential accompanying toxic side effects. This article is protected by copyright. All rights reserved.
Mohamed SH, Mohamed MSM, Khalil MS, et al. Combination of essential oil and ciprofloxacin to inhibit/eradicate biofilms in multidrug-resistant Klebsiella pneumoniae. J Appl Microbiol. 2018 Mar 8.