TITLE:
Characterization of a Novel MDH1 Bacterium from a Virgin Hot Spring Applicable for Gold Nanoparticle (GNPs) Synthesis
AUTHORS:
Nurul Alam, Manas Sarkar, Trinath Chowdhury, Dipak Ghosh, Brajadulal Chattopadhyay
KEYWORDS:
Hot Spring Bacteria, Phylogenetic Characterization, Green Synthesis, Gold Nanoparticles
JOURNAL NAME:
Advances in Microbiology,
Vol.6 No.9,
August
17,
2016
ABSTRACT: Background: Use of novel microorganisms for
beneficial purposes is still remaining a challenging job. This study was
designed to isolate, characterize and use of a novel hot spring bacterial
strain from a virgin hot spring of Metaldanga, Birbhum, West Bengal, India. Methods:
A pure bacterial strain (MDH1) was identified by growing the enrichment culture
isolated from Metaldanga hot spring through serial dilution process in a
semi-synthetic medium at pH 8.0 and 42°C temperature. The novelty of the strain was
characterized by 16S-rRNA gene sequence analysis. The bacterium acted as
template to synthesize spherical gold nanoparticles (GNPs). GNPs were
characterized by using UV-Vis spectroscopy, X-ray diffraction (XRD), dynamic
light scattering (DLS) and Fourier transform infra-red spectroscopy (FTIR). Results:
The phylogenetic analysis suggested that MDH1 strain (GenBank accession number:
KT600031) was affiliated to the family “Pseudomonadaceae”
with 99% homologous to Pseudomonas putida H8234. The coccoid shaped
bacterium was gram-negative and facultative-anaerobic which acted as a template
to synthesize spherical GNPs with an average size of 12 ± 3 nm when examined
under transmission electron microscopy (TEM). FT-IR studies revealed the presence of
bioactive functional groups which acted as capping and stabilizing agents of
the GNPs. XRD pattern confirmed the amorphous nature of GNPs. The Zeta
potential (ζ) concluded the adequate
stability of GNPs in an aqueous environment. Conclusions: The present investigation
explores the microbial diversity of a virgin hot spring of Metaldanga for its
beneficial applications in industry, particularly in the synthesis of the gold
nanoparticles.