Antibacterial Activities of Biosynthesized ZnO Nanoparticles Using Leaf and Fruit Extracts of Neolamarckia cadamba.

Zinc oxide nanoparticles have been biosynthesized with the help of Neolamarckia cadamba leaf and fruit extracts. ZnO nanoparticles were tested for antibacterial activity before and after calcination against Gram positive (Staphylococcus aureus, Bacillus subtilis) as well as Gram negative micro-organisms (Escherichia coli, Pseudomonas aeruginosa) within the concentration range 0.625-10 mg/mL with the help of well diffusion technique. Higher antibacterial potential has been observed in ZnO nanoparticles synthesized using leaf extract in comparison with those synthesized using fruit extract. Increased antibacterial activity was observed before calcination as compared to after calcination. ZnO synthesized using leaf extract were observed to show significant antibacterial potential against E. coli, S. aureus along with P. aeruginosa before calcination as well as against E. coli after calcination. Similarly, ZnO nanoparticles synthesized using fruit extract exhibited antibacterial activity against E. coli and P. aeruginosa before calcination and against E. coli after calcination. Both the ZnO nanoparticles before and after calcination did not show any antibacterial activity against B. subtilis. Thus, ZnO nanoparticles can serve a dual purpose by its application as an antibacterial agent against susceptible micro-organisms as well as biocompatible carrier system for drug delivery applications in case of non-antibacterial properties by virtue of its inertness as well as easy disposal.