Synthesis and characterization of linezolid conjugated silver nanoparticles using Thespesia Populnea leaf extract and evaluation of antibacterial efficacy against MDR pathogens: A novel method against MDR bacteria

Objective(s): Multidrug-resistant (MDR) organisms are posing threat by exhibiting resistance to commonly used antibiotics. From our study, we found a novel strategy to enhance the efficacy of antibiotics, which could help in treating diseases caused by various pathogens. We have used a natural, low-cost, biological reducing and capping agent, Thespesia populnea leaf extract to synthesize silver nanoparticles (AgNPs) and linezolid-conjugated silver nanoparticles (Li-AgNPs).Materials and Methods: The nanoparticles were characterized by UV-visible spectroscopy, Scanning Electron Microscope (SEM), X-Ray Diffraction (XRD), and Fourier Transform Infrared (FT-IR) spectroscopy. The antimicrobial activity was evaluated against MDR Staphylococcus aureus, Enterococcus faecalis, and Enterococcus faecium by agar well plate method. The UV-visible absorption spectra showed absorption peaks at 442 nm and 464 nm for AgNPs and Li-AgNPs, respectively. Results: The SEM analysis revealed particle size with a diameter ranging from 18 to 22 nm and 24 to 32 nm, respectively, and spherical in shape. The FT-IR spectrum has a distinct absorption band at 2065 cm-1 confirms adsorption of antibiotic linezolid on the AgNPs. The XRD pattern showed the characteristic absorption bands of 2 theta values, which confirms that NPs are crystalline in nature. The AgNPs and Li-AgNPs have exhibited the antibacterial potency. The Li-AgNPs have showed 25.8%, 7.6%, and 12.5% more microbial growth inhibition compared to antibiotic linezolid against E. faecalis, E. faecium,and S. aureus,respectively. Conclusion: All these results clearly indicated that the Li-AgNPs possesses enhanced antimicrobial activity than antibiotic linezolid, indicating the usefulness of this novel strategy to treat various communicable diseases caused by MDR pathogens.

Synthesis and characterization of linezolid conjugated silver nanoparticles using Thespesia Populnea leaf extract and evaluation of antibacterial efficacy against MDR pathogens: A novel method against MDR bacteria Keywords:

Communicable diseases , Staphylococcus aureus , Enterococcus faecalis , Enterococcus faecium , Anti-Bacterial Agents , Linezolid