Production of Copper Nanoparticles by Aspergillus niger and Evaluation of their Biomedical Applications

Nanotechnology is a well advanced area and different types of nanoparticles are now produced. The most revolutionary topic of the twenty-first century is nanotechnology. Recently, metallic nanoparticles (NPs) have gained a lot of attention. In this study a straightforward, safe, and economical method is used for synthesizing copper nanoparticles (CuNPs) by using cell free filtrate of Aspergillus niger. Fungi secretes enormous amount of enzymes which act as reducing as well stabilizing agents. Synthesized CuNPs were characterized by different techniques. Ultraviolet (UV)-visible spectrophotometer showed a characteristic peak at 380nm, Dynamic Light Scattering (DLS) analysis indicated that CuNPs have average size of 570nm with 0.480 PDI. SEM (Scanning Electron Microscopy) revealed CuNPs are of cubic shape. As per FTIR (Fourier Transform Infrared Analysis) two functional groups i.e., -O-H- and C=C- on the surface of CuNPs. Genetic analysis of Aspergillus niger revealed the presence of nitrate reductase enzyme that may involve in reduction of metal into NPs. Furthermore, CuNPs showed significant antibacterial action against Escherichia coli, Bacillus subtilis, Staphylococcus aureus, and Klebsiella pneumoniae with 17mm, 20mm, 17mm and 20mm respectively. CuNPs also showed antioxidant potential with 59.41µg/ml.