PRELIMINARY INVESTIGATION OF BAKER’S YEAST FOR THE BIOSYNTHESIS OF METAL OXIDE NANOPARTICLES AND EVALUATION OF THEIR ANTIBACTERIAL ACTIVITY

Abstract

The present study determined if metal ions (zinc sulphate, silver nitrate, copper sulphate, manganese sulphate and ferric chloride) can be used as precursors to prepare nanoparticles using a baker’s yeast culture medium. The particles were characterized using Fourier transform infrared (FTIR), scanning electron microscope‒energy-dispersive X-ray (SEM-EDX), transmission electron microscopy (TEM), and X-ray powder diffraction (XRD). The antibacterial activity against Escherichia coli and Streptococcus aureus was also evaluated. Saccharomyces cerevisiae strain A12 culture only synthesized nanoparticles using a silver nitrate solution. FTIR indicated that the protein might play a role in capping the nanoparticles, which formed large aggregates and contained silver, oxygen and a small amount of phosphorus. The nanoparticles were spherical, ranging in size from 9 to 85 nm, crystalline and characterized as Ag2O, however, they demonstrated weak antibacterial activity.

Keywords

• antibacterial activity
• biosynthesis
• nanoparticles
• saccharomyces cerevisiae
• silver