Abstract
Various methods have been employed in controlling contamination of food and feed commodities by fungi and their toxins as well as in the management of associated diseases in various plant and animal species. However, one of the challenges in addressing these problems over the years has been the development of drug resistance by some fungal species. In addition, the lack of effectiveness of some of the drugs or antibiotics when utilized in isolation is another problem being faced. Therefore, incorporation of nanoparticles with antibiotics can be a breakthrough as the positive interactive activity between the two may enhance the effectiveness of the already existing antibiotics against opportunistic fungal species and associated diseases. The tenacity of this study was to enhance the antimicrobial effect of various antimicrobial agents against some mycotoxigenic and pathogenic fungi using CuNPs. In the present study, the synthesis of CuNPs was achieved by chemical reduction method using a reducing agent, ascorbic acid in the presence of polyethylene glycol (PEG-1000). Furthermore, ultraviolet-visible (UV-vis) light absorption spectra, scanning electron microscopy (SEM), X-Ray Diffraction (XRD) and Fourier Transform Infrared Spectroscopy (FTIR) techniques were utilized in characterizing the synthesized CuNPs. Individual antifungal activities of commercial antimicrobials, CuNPs and their conjugates were evaluated using the Kirby-Bauer disk diffusion assay. Initially, UV-vis spectroscopy was used to monitor the synthesis of CuNPs, which revealed a CuNP peak at 575 nm. FTIR further confirmed the coordination of PEG and CuNPs as expected and SEM micrographs confirmed the surface morphology of CuNPs even though agglomeration was observed. Antimicrobial study revealed the inhibition of fungal growth by some of the tested antimicrobial agents. Furthermore, the positive interactive effect of those active antibiotics and CuNPs resulted in an increase in 1.2 to 1.6 fold-area in antifungal activity, revealing that their conjugation enhanced their antimicrobial efficacy against the test pathogenic fungi.
M.Sc. (Nanoscience)