9 research outputs found
Characterization of an exopolysaccharide produced by a marine <i>Enterobacter cloacae</i>
467-471An exopolysaccharide producing marine
bacterium, Enterobacter cloacae, was isolated from marine sediment
collected from Gujarat coast, India.
Chemical investigation of exopolysaccharide (EPS 71 a) revealed that this
exopolysaccharide was an acidic polysaccharide containing high amount of uronic
acid, fucose and sulfate which is rare for bacterial exopolysaccharides. EPS
71a was found to have fucose, galactose, glucose and glucuronic acid in a molar
ratio of 2:1:1:1
Antibacterial and Antioxidant Activities of Novel Actinobacteria Strain Isolated from Gulf of Khambhat, Gujarat
Bacterial secondary metabolites possess a wide range of biologically active compounds including antibacterial and antioxidants. In this study, a Gram-positive novel marine Actinobacteria was isolated from sea sediment which showed 84% 16S rRNA gene sequence (KT588655) similarity with Streptomyces variabilis (EU841661) and designated as Streptomyces variabilis RD-5. The genus Streptomyces is considered as a promising source of bioactive secondary metabolites. The isolated novel bacterial strain was characterized by antibacterial characteristics and antioxidant activities. The BIOLOG based analysis suggested that S. variabilis RD-5 utilized a wide range of substrates compared to the reference strain. The result is further supported by statistical analysis such as AWCD (average well color development), heat-map and PCA (principal component analysis). The whole cell fatty acid profiling showed the dominance of iso/anteiso branched C15–C17 long chain fatty acids. The identified strain S. variabilis RD-5 exhibited a broad spectrum of antibacterial activities for the Gram-negative bacteria (Escherichia coli NCIM 2065, Shigella boydii NCIM, Klebsiella pneumoniae, Enterobacter cloacae, Pseudomonas sp. NCIM 2200 and Salmonella enteritidis NCIM), and Gram-positive bacteria (Bacillus subtilis NCIM 2920 and Staphylococcus aureus MTCC 96). Extract of S. variabilis strain RD-5 showed 82.86 and 89% of 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging and metal chelating activity, respectively, at 5.0 mg/mL. While H2O2 scavenging activity was 74.5% at 0.05 mg/mL concentration. Furthermore, polyketide synthases (PKSs types I and II), an enzyme complex that produces polyketides, the encoding gene(s) detected in the strain RD-5 which may probably involve for the synthesis of antibacterial compound(s). In conclusion, a novel bacterial strain of Actinobacteria, isolated from the unexplored sea sediment of Alang, Gulf of Khambhat (Gujarat), India showed promising antibacterial activities. However, fractionation and further characterization of active compounds from S. variabilis RD-5 are needed for their optimum utilization toward antibacterial purposes
Influence of low salinity stress on virulence and biofilm formation potential in
The Gujarat government has proposed a project to convert a part of the Gulf of Khambhat
(GoK), located in western India, into the world’s largest man-made freshwater reservoir in
the near future (http://www.kalpasar.gujarat.gov.in/mainpage.ht
Assessment of heavy metal content in suspended particulate matter of coastal industrial town, Mithapur, Gujarat, India
Heavy metal concentrations in suspended particulate matter (SPM) were investigated for their
distribution and source in the atmosphere of coastal industrial town, Mithapur, Gujarat, India.
SPM, at 10 locations covering three seasons, were trapped on glass fibre filters using high
volume samplers and quantification of metals (Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb and Zn) was done
using Atomic Absorption Spectrometry employing HNO3 based wet digestion. Results show
relatively low concentrations of SPM (211.3 to 375.2 ÎĽg/m3) compared to National Ambient Air
Quality Standard (NAAQS), specified By Central Pollution Control Board (CPCB, India),
however, they were 2–3 times higher as compared to reference site. Among the heavy
metals Cr, Mn and Pb levels were low, while Ni and Cd found to be exceeding the USEPA
standards. The metal levels were also compared with those reported for other rural, coastal,
industrial and urban parts around the world. Enrichment Factor analysis indicated that Cd, Zn,
Cu, Pb and Ni were highly enriched relative to their crustal ratios (to Fe) and correspond to
substantial contribution of anthropogenic source of these metals. The source identification was
carried out by principal component analysis by applying a Varimax Rotated Component Matrix
Occurrence and distribution of selected heavy metals and boron in groundwater of the Gulf of Khambhat region, Gujarat, India
The concentration of selected heavy metals, like
As, Co, Cr, Cu, Fe, Mn, Ni, Pb, and Zn as well as B, was
measured by inductively coupled plasma–optical emission
spectrometry (ICP–OES) in groundwater samples from various
locations in the Gulf of Khambhat (GoK), an inlet of the
Arabian Sea in the state of Gujarat, India, during postmonsoon,
winter, and pre-monsoon seasons in a year. Most
heavy elements are characterized by low mobility under
slightly alkaline and reducing conditions; concentrations in
confined aquifers are smaller than the maximum permissible
values for drinking water. The temporal changes indicate that
a majority of metals is entering the aquifer during monsoon.
Principle component analysis of the heavy metal data suggests
that Co, Cu, Cd, and Zn are interrelated with each other and
derived significantly from anthropogenic route, while input of
Pb and Cr may be due to atmospheric deposition in the study
area. Both weathering of rocks and anthropogenic input were
found to be main sources of elements in the groundwater. The
heavy metal levels in groundwaters of the GoK region in
comparison with some of the European and Asian sites were
higher; however, these metal levels were found to be comparable
with few urban sites in the world