ANTIMICROBIAL AND ANTIBIOFILM ACTIVITY OF AZADIRACHTA INDICA SILVER NANOPARTICLES AGAINST ENTERIC PATHOGENS ISOLATED FROM EFFLUENT SAMPLES

The aim of this study was to evaluate the antimicrobial and antibiofilm activity of silver nanoparticles of Azadirachta indica (AISNPs) against the pathogens isolated from effluent. Green synthesis approach was opted for the synthesis of the synthesis of AISNPs by using the ethanolic extract of Azadirachta indica which was added to 1mM solution of AgNO₃. These synthesized nanoparticles were molecularly characterized by UV-Visible spectrophotometer, TEM, Zeta Sizer, Zeta Potential, XRD and FTIR respectively. Antimicrobial activity of the AISNPs was carried by well diffusion method on Muller Hinton Agar against biofilm-producing multi-drug resistant effluent pathogens, which were identified as E. coli, P. aeruginosa, S. aureus and K. pneumoniae. The zone of inhibition of AISNPs observed in case of E. coli was 16.08 mm, 18.65 mm against S. aureus, 10.46 mm against P. aeruginosa and 15.34 mm against K. pneumoniae. Antibiofilm activity of AISNPs demonstrated the decline of biofilm producing activity by 76% against P. aeruginosa, 74% against S. aureus, 60% against K. pneumoniae and 59% against E. coli respectively, indicating the strong antibiofilm properties of the AISNPs. It can be concluded from the present study that green synthesized AISNPs can be used as an alternate approach to combat the multiple drug-resistant biofilm producing pathogens isolated from effluent.