Plants and microbes assisted selenium nanoparticles: characterization and application

K. S. Siddiqi ,Azamal Husen

doi:10.1186/preaccept-4680053311297707

Abstract

Selenium is an essential trace element and is an essential component of many enzymes without which they become inactive. The Se nanoparticles of varying shape and size may be synthesized from Se salts especially selenite and selenates in presence of reducing agents such as proteins, phenols, alcohols and amines. These biomolecules can be used to reduce Se salts in vitro but the byproducts released in the environment may be hazardous to flora and fauna. In this review, therefore, we analysed in depth, the biogenic synthesis of Se nanoparticles, their characterization and transformation into t- Se, m-Se, Se-nanoballs, Se-nanowires and Se-hollow spheres in an innocuous way preventing the environment from pollution. Their shape, size, FTIR, UV–vis, Raman spectra, SEM, TEM images and XRD pattern have been analysed. The weak forces involved in aggregation and transformation of one nano structure into the other have been carefully resolved.

Highlights

Selenium was known as a notorious element until it was recognized by Schwarz and Foltz in 1957 as an essential trace element for both plants and mammals
The main objective of this review is to identify the plant extracts and bacterial strains involved in the biosynthesis of Se nanoparticles
Bioreduction of selenate or selenite from microorganism such as bacteria, fungi and plant extract have become the favourite pursuit of biologist, chemist and engineers

Summary

Introduction

Selenium was known as a notorious element until it was recognized by Schwarz and Foltz in 1957 as an essential trace element for both plants and mammals. The extract contains fairly substantial amount of reducing sugars and they help in the reduction and formation of Se nanoballs These authors have given a flow diagram for Se nanoparticles synthesis but it does not reveal the chemical changes which occur as a consequence of redox reactions. The UV–vis spectrum of the C. annum protein (washed with SDS-PAGE gel) with molecular weight of 30 kDa, showed peak (210 nm) corresponding to peptide bonds and amino residues (280 nm) As these are reducing agents they help in the formation of nanoparticles. Since SeO3 2− in ionic form is toxic to bacterial culture, the bacteria in selenite solution may die and the disintegrated protein may act as reducing agent for selenite. Since E. coli contains many other proteins than only pAdhP (purified protein), the decrease in Se nanoparticle size may be the cumulative effect of all proteins available in E. coli

Conclusion

40. Finley J

42. Finley J