Optimized Resting Cell Method for Green Synthesis of Selenium Nanoparticles from A Yarrowia Lipolytica Mbc۲۵

Recently, there has been unprecedented growth in nanotechnology. This has made nanoparticles revolutionize the field of biomedicine, especially drug delivery, due to their unique properties such as target site specificity, systemic stability, and high level of solubility. However, few nanotoxicology studies have uncovered the toxic effects of different nanoparticles like titanium, copper, silver, alumina, zinc, iron, and silica. In recent years, the nano form of selenium has attracted considerable attention. Many studies discovered the ability of selenium nanoparticles to show antibacterial, antioxidant, anti-biofilm, and more importantly anti-cancer properties. In the biosynthesis method of nanoparticles, different microorganisms are used, yeast is one of them. Yarrowia lipolytica yeast can accumulate and detoxify heavy metals due to its reductase enzymes and reduce metal salts to nanoparticles with a narrow size and less dispersion. The rapid growth of this yeast strain as well as the use of simple nutrients have made it suitable for biosynthesis. This research aimed to use the yeast strain as a biocatalyst for the biological reduction of sodium selenite to selenium nanoparticles. For this purpose, the synthesis of selenium nanoparticles was carried out using the resting cell strategy and under optimal conditions. The results of this research showed that the Yarrowia lipolytica yeast strain was able to produce spherical selenium nanoparticles with an average size of ۷۰ in the optimal conditions of ۴ mM sodium selenite concentration, optimal pH ۶.۵, optimal temperature ۳۰ °C after ۲۴ hours of incubation. Selenium nanoparticles synthesized by Yarrowia lipolytica yeast were characterized by images obtained from growth electron microscope analysis, X-ray diffraction, infrared spectroscopy analysis, and of examining the size distribution range of nanoparticles. The results showed that these nanoparticles could be a proper green alternative for other nanoparticles with toxicity

Keywords:

selenium nanoparticles , biosynthesis , Yarrowia lipolytica yeast , toxicity , drug delivery.