Ecofriendly phytosynthesized zirconium oxide nanoparticles as antibiofilm and quorum quenching agents against Acinetobacter baumannii

Abstract

The worldwide increase of multi-drug resistance has directed the researchers to focus on ecofriendly ways of nanoparticles synthesis with effective antivirulence properties. Here, we report the antibiofilm and quorum quenching (QQ) potential of zirconium oxide nanoparticles (ZrO₂ NPs) synthesized from aqueous ginger extract against multi-drug resistant (MDR) Acinetobacter baumannii. The results indicated that ZrO₂ NPs were of tetragonal shape with average diameter of 16 nm. Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values for A. baumannii were 15.6 and 62.5 µg/ml, respectively, as revealed by broth microdilution assay. Exposure of bacterial cells to ZrO₂ NPs resulted in reactive oxygen species (ROS) generation which in turn led to cellular membrane disruption as observed by an increase in leakage of cellular contents, such as proteins, sugars, and DNA. The antibiofilm activity was evaluated by microtiter plate assay and the results revealed that the percentage inhibition of biofilm was found to be 14.3–80.6%. ZrO₂ NPs also obstructed the chemical composition of biofilms matrix by reducing the proteins and carbohydrate contents. Molecular docking studies of ZrO₂ NPs with four proteins (2NAZ, 4HKG, 5D6H, and 5HM6) involved in biofilm formation of A. baumannii revealed the interaction of zirconium with target proteins. These findings suggested the in vitro efficacy of phytosynthesized ZrO₂ NPs as antibiofilm and QQ agents that can be exploited in the development of alternative therapeutic options against MDR A. baumannii.

Keywords:

• A. baumannii
• antibiofilm
• molecular docking
• phytosynthesized ZrO₂ NPs
• quorum quenching

Disclosure statement

No potential conflict of interest was reported by the author(s).