Comparative analysis of biofabricated silver nanoparticles as antibiofilm agents on Pseudomonas aeruginosa

Microbial cells in the biofilm were characterized with significant features like antimicrobial resistance and bio fouling properties, which make them distinguishable from their planktonic forms. Although many antimicrobial drugs and antibiotics were reported for biofilm inhibition and dispersal, these compounds had limited applications because of drug resistance. Development of antibiofilm agents which could overcome the drug resistant bacteria had been a challenge over the years. In order to overcome development of drug resistance, silver nanoparticles were being used, to coat the medical devices. This strategy, though successful to some extent, suffer with toxic effects on eukaryotic cells in application. Hence there arises a need to explore natural compounds with antibiofilm activity. Natural products established as antibacterial agents were also found to have quorum quenching activity. Garcinia (Garcinia cambogia) and Ginger (Zingiber officinale) extracts were observed to possess quorum quenching activity in the lab, therefore used for biofabrication to enhance the antimicrobial activity of silver nanoparticles. Pseudomonas aeruginosa being a most potent biofilm forming bacteria in various environments, like infections, food spoilage and bio fouling in medical devices etc. The study aimed to figure out a novel antibiofilm agent, which could inhibit or eliminate biofilms by using a combination of biologically synthesized nanoparticles and natural quorum quenching agents. Comparative analysis of bio fabricated nanoparticles on the inhibition and dispersal of Pseudomonas biofilms was performed with non fabricated nanoparticles using microtiter based assay, followed by SEM and Flow cell cytometry techniques. Fabricated GNP (fGNP) had showed 17.9% more inhibition which indicates - 2 fold enhancement in biofilm inhibition activity. Similarly 9.45% enhancement was found in dispersal activity by fGNP. These results were encouraging us to improve upon the combinatorial approach and to formulate an ideal antibiofilm agent with minimal scope for emergence of antimicrobial resistance.