Biogenic Synthesis of Zinc Oxide (ZnO) Nanoparticles Using a Fungus (Aspargillus niger) and Their Characterization

Abstract

Nanoparticles are ultrafine structures with dimensions less than 100 nm. Nanoparticles have diverse applications. There are three important methods of fabrication of nanoparticles namely physical, chemical and biological methods. Physical method is a top down strategy for the fabrication of nanoparticles. It is energy intensive and time consuming. A chemical method is simple, but is expensive and requires expensive chemicals with high purity and also involves hazards of contaminations. Biological synthesis is very simple, cheap and environment friendly, requiring no expensive chemicals, temperature and is time saving. Plants and microorganisms are commonly used in this method. These are available everywhere. In the present work we synthesized Zinc Oxide (ZnO) nanoparticles by biological method using Aspargillus niger and zinc chloride (ZnCl2) as precursors. Biogenic synthesis of metallic nanoparticles by fungi is a safe and economical process because of formation of stable and small sized nanoparticles. Fungal biomass secretes proteins which act as reducing and stabilizing agents. The synthesized nanoparticles were characterized by XRD (X-Ray Diffraction), SEM (Scanning Electron Microscopy), UV-Vis (Ultraviolet, Visible) and EDX (Energy Dispersive X-Ray) techniques. Their size was in nm range and morphology of synthesized ZnO NPs was hexagonal. The ZnO nanoparticles are one of the most versatile materials and are used in cosmetics and in Bioenergy production, as a catalyst and as antibacterial material.

Green synthesis and characterization of zinc oxide nanoparticles using extracts of Artemisia annua l. grown in Togo

“…The fig. 3 These findings are in agreement with the results that confirmed the crystalline nature of nanoparticles reporting a similar kind of peak indices for ZnONPs synthesized using different extracts of Cassia fistula and Melia azadarach [42], Calotropis gigantean [43], Fungus (Aspargillus niger) [44], Scadoxus multiflorus [45], Cymodocea serrulata [46], L. nobilis [40], P. hysterophorus L. [47], Nyctanthes arbor-tristis [48] and green crops [49]. The average size of the ZnONPs was estimated using XRD Crystallite (grain) Size Calculator [37] from the Scherrer formula.…”

Synthesis of ZnO nanoparticles by two different methods & comparison of their structural, antibacterial, photocatalytic and optical properties

“…Researchers proposed several possible plant extracts and fungal biomasses that were used in the green synthesis of ZnO NPs such as Aloe Barbadensis Miller (Aloe Vera) leaf extract [9], Poncirus trifoliate leaf extract [10], Parthenium hysterophorus L. (Carrot grass) leaf extract [11], Aspergillus aeneus [12], Calotropis procera latex [13], Sedum alfredii Hance [14], Physalis alkekengi L. [15], etc. However, the smaller particle size of ZnO NPs was observed by using Poncirus trifoliate leaf extract (8.48-32.51 nm), while for others, the results were satisfactory.…”

A Review on Biofabrication of Zinc Nanoparticles, Its Mechanism and Recent Applications

“…Fungi produce large amount of proteins and enzymes and as a result the yield of nanoparticles by fungi produce proteins and enzymes and as a result the yield of nanoparticles is high. Extracellular synthesis of nanoparticles by fungi produce protein stabilized nanoparticles and allows an efficient way to extract nanoparticles from them [39]. Mostly fungi were chosen because of its resistance to process conditions and variations such as pressure, flow rate and stirring which enhance their potential use for large scale synthesis.…”

“…Since, it can release higher concentrations of metabolites to the culture media than bacteria cells [40]. There are wide applications of fungi as they produce huge enzymes, ease in the scale-up process, economic viability, high binding capacity is in handling the biomass [39]. Fungi has been reported to possess secondary metabolites responsible for the antifungal, antibacterial, anti-cancerous properties.…”

“…Zinc Oxide NPs are formed when electrons are transported from NADH by an Enzyme NADH reductase to Zn +2 which are reduced into ZnO NPs. In intracellular synthesis, transportation of metal ions within the cell takes place where they are reduced by enzymes present there which leads to increase in nuclei resulting in nanoparticles formation in the periplasmic space and cytoplasm [39]. Mukherjee et al [42] reported intracellular mechanism for NPs by Verticillium sp.…”