Green Synthesis, Characterization and Antimicrobial Activity of Silver Nanoparticles (AgNPs) from Maize (Zea Mays L.)

Abstract

In recent years, the biosynthesis (green synthesis) of metal nanoparticles such as silver nanoparticles (AgNPs) have become one of the safest, most cost-effective and environmentally friendly approaches. In this study, AgNPs were synthesized using maize (Zea mays L.) leaves. For the characterization of synthesized AgNPs different techniques were used, such as X-ray diffraction spectroscopy (XRD), Ultraviolet visible (UV-Vis) spectroscopy, transmission electron microscopy (TEM), Energy dispersive X-ray spectroscopy (EDX), Fourier-transformed infrared spectroscopy (FT-IR) and Thermal gravimetric and Differential thermal analysis (TGA-DTA). The XRD results showed that AgNPs had a mean diameter of 12.63 nm and a crystal-like appearance. In addition, antimicrobial activities of synthesized AgNPs were evaluated using 3 different antibiotics against Gram-negative Escherichia coli and Gram-positive Staphylococcus aureus bacteria and Candida albicans yeast. Antifungal activity of AgNPs with antibiotics has been observed to be better than the antibiotics against Gram-positive and Gram-negative bacteria. The minimum inhibitory concentrations were found to be 0.084, 0.337 and 0.021 mg mL(-1) for Escherichia coli, Staphylococcus aureus, and Candida albicans, respectively. The results revealed that AgNPs synthesized from maize leaf extract have antibacterial activity against Gram-negative Escherichia coli, Gram-positive Staphylococcus aureus and antifungal activity against Candida albicans yeast, and that the produced AgNPs could be used in the production of biomedical products and in the pharmaceutical industry.