Optimizing Physioculture Conditions for the Synthesis of Silver Nanoparticles from Aspergillus niger

Abstract

physiochemical parameters such as fungal biomass quantity, pH, incubation temperature and silver nitrate concentration will not only affect the rate of synthesis of silver nanoparticles from Aspergillus niger but also its yield. So in order to enhance product yield optimization of external environment was done to control the above mentioned parameters. A peak at 420 nm was observed for silver nanoparticles by UV visible spectrometry and at 420 nm maximum synthesis of silver nanoparticles were obtained at optimum conditions i.e. 20 g of fungal biomass, alkaline pH of 9.0, incubation temperature of 60°C and 6 mM of AgNO3 , Faculty of Life Sciences and Informatics, Balochistan University of Information Aspergillus niger T echnology Engineering and Management Sciences, concentration. Keywords: Aspergillus niger; Fungal biomass quantity; pH; Incuba- the mycelia was harvested using Whatman’s filter paper no.1. The cell tion temperature; AgNO3 concentration free filtrate was than centrifuged at 15000 rpm for 10 min to obtain the supernatant. Introduction Mycosynthesis of silver nanoparticles Metallic nanoparticles, such as iron, selenium, platinum, lead, silica, titanium, gold, silver and zirconium can be synthesized by different 10 ml of supernatant incubated with 90 ml of 2 mM AgNO3 at room biological organisms [1]. These organisms make use of their biomass temperature in dark for 48 hours. Appearance of brown/black color or their biomass extracts as the basis of extracellular or intracellular of the media incubated with AgNO3 indicates mycosynthesis of silver synthesis of nanoparticle by reducing the metal ions. For example iron nanoparticles. Control containing freshly prepared CD media with oxide nanoparticles were synthesized by Bacterias like Desulfuromonas aqueous silver nitrate was run simultaneously with the experimental acetoxidans, Shewanella spp and Magnetospirillum magnetotacticum flasks. Experiment and control were performed in triplicates. [2]. From aqueous extracts of Rumex acetosa (dicotyledonous) Characterization of silver nanoparticles and Hordeum vulgare (monocotyledonous) plants iron oxide nanoparticles were produced [3]. However exploration of Fungi for UV visible spectrometry (JENWAY 6305) analysis was done by the mycofabrication of metallic nanoparticles is the most apt choice scanning the absorption spectra from 360 nm to 460 nm to find because of its high tolerance and bioaccumulation capabilities [4]. out λmax where maximum optical density was obtained. It is well Therefore “Fungi” is the right choice of biological organism employed known that monodispersed nanoparticles show one plasma band in for the large scale mycofabrication of different nanoparticles. Since the visible region of the spectrum. Optical density of distill water was physiochemical conditions influence the growth and developments of used as a control’. an organism in vitro and in vivo. The metabolic activity of an organism Optimization of Reaction Conditions is thus influenced by the external environment. In case of extracellular synthesis of silver nanoparticle by Aspergillus niger, enzyme production Fungal biomass quantity is greatly influenced by the condition in which the fungi is cultivated. The effect of biomass concentration on the extracellular production Therefore optimization studies of the physioculture conditions such of silver nanoparticles was studied by using different wet biomass of the as pH, incubation temperature, substrate concentration and fungal fungus Aspergillus niger with a difference of 5 i.e. 5 g, 10 g, 15 g and biomass etc. was done to determine optimum conditions for silver 20 g grown in cezapex Dox broth. 10 ml of obtained supernatant nanoparticles synthesis. incubated with 90 ml of 2 mM AgNO3 at room temperature in Materials and Methods dark for 48 hours. Biosynthesis of nanosilver particles at different biomass concentrations was characterized by UV-visible absorption Isolation and identification of the fungus spectroscopy. Aspergillus niger, isolated from soil and maintained on potato dextrose agar (PDA) at 28°C for 4-5 days. The fungus was identified on the basis of morphological characteristics such as color of the colony, texture of the mycelia etc. Aspergillus niger culturing Aspergillus niger was inoculated by wire loop method in IL of cezapex Dox broth (glucose (10 g), Sodium nitrate (2 g), ferrous sulphate (0.01 g), yeast extract (1 g), calcium chloride(0.5 g), potassium dihydrogen phosphate(1 g), zinc sulphate (0.01 g) and magnesium sulphate (0.5 g) dissolved in 1000 ml of distilled water and autoclaved at 121°C and 15 psi (pound/square inches) for 20 min at room temperature for 5 days on a rotatory shaker at 150 rpm. Later *Corresponding author: Nida Tabassum Khan, Department of Biotechnology, Faculty of Life Sciences and Informatics, Balochistan University of Information Technology Engineering and Management Sciences, (BUITEMS), Quetta, Pakistan, Tel: +92 81 111 717 111; E-mail: nidatabassumkhan@yahoo.com Received September 10, 2016; Accepted October 10, 2016; Published October 18, 2016 Citation: Khan NT, Jameel N, Rehman SUA (2016) Optimizing Physioculture Conditions for the Synthesis of Silver Nanoparticles from Aspergillus niger. J Nanomed Nanotechnol 7: 402. doi: 10.4172/2157-7439.1000402 Copyright: © 2016 Khan NT, et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. J Nanomed Nanotechnol, an open access journal ISSN: 2157-7439 Volume 7 • Issue 5 • 1000402