Evaluating the Potential of the Native Yeast Yarrowia Lipolytica as a Biological Safe Source for the Synthesis of Selenium Nanoparticle

Among metal nanoparticles, elemental selenium nanoparticles (SeNPs) are considered for their low toxicity and vitality in the human body. Yarrowia lipolytica yeast, due to its reductase enzymes, has the ability to accumulate and detoxify heavy metals and reduce metal salts to nanoparticles with a narrow size and less dispersion. The aim of the present study was to use Y. lipolytica strain MP10 as a biological safe source for the biological synthesis of SeNP.

Agar dilution method was used for determining the resistance pattern of Y. lipolytica strain MP10 to selenite oxyanion. Synthesis of SeNPs was investigated under resting cell strategy. The effects of selenite oxyanion concentrations and also time incubation on the production rate, size, and dispersity of SeNPs were investigated in the bioconversion reaction. SeNPs produced with Y. lipolytica strain MP10 were defined by images obtained from Scanning Electron Microscopy (SEM) analysis, energy-dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), and Fourier-transform infrared spectroscopy (FTIR).

The obtained results demonstrated that Y. lipolytica strain MP10 showed tolerance to selenite oxyanion up to 10 mm. The yeast strain, at the optimal condition of 4 mM sodium selenite, and after 24 hours of incubation, was able to produce spherical SeNPs with an average size of 70 nm. As the incubation time increased, the dispersion of spherical SeNPs reduced and the average size of the nanoparticles increased to 117 nm after 72 h incubation. 

Discussion and Conclusion:

The present study is a report on the capability of native yeast Yarrowia lipolytica for the successful synthesis of SeNP under resting cell strategy and the improvement in the dispersion and particle size of the nanoparticles in the optimal incubation time.