scholarly journals Characterization of heavy metals resistant heterotrophic bacteria from soils in the Windmill Islands region, Wilkes Land, East Antarctica

2014 ◽  
Vol 35 (4) ◽  
pp. 593-607 ◽  
Author(s):  
Iva Tomova ◽  
Margarita Stoilova−Disheva ◽  
Evgenia Vasileva−Tonkova

AbstractIn this study, selected heavy metals resistant heterotrophic bacteria isolated from soil samples at the Windmill Islands region, Wilkes Land (East Antarctica), were characterized. Phylogenetic analysis revealed affiliation of isolates to genera Bacillus, Lysinibacillus, Micrococcus and Stenotrophomonas. The strains were found to be psychrotolerant and halotolerant, able to tolerate up to 10% NaCl in the growth medium. The Minimum Inhibitory Concentration of the seven heavy metals Cr, Cu, Ni, Co, Cd, Zn, and Pb was determined in solid media for each bacterial strain. Gram−positive Vi−2 strain and Gram−negative Vi−4 strain showed highest multiply heavy metals resistance, and Vi−3 and Vi−4 strains showed multi−antibiotic resistance to more than a half of the 13 used antibiotics. Plasmids were detected only in Gram−negative Vi−4 strain. The bacteria were able to produce different hydrolytic enzymes including industrially important proteases, xylanases, cellulases, and β−glucosidases. High heavy metals resistance of the Antarctic bacteria suggests their potential application for wastewater treatment in cold and temperate climates. Highly sensitive to Cd and Co ions Vi−1, Vi−5 and Vi−7 strains would be promising for developing biosensors to detect these most toxic heavy metals in environmental samples.

Geomorphology ◽  
2017 ◽  
Vol 292 ◽  
pp. 1-15 ◽  
Author(s):  
C.J. Carson ◽  
A.L. Post ◽  
J. Smith ◽  
G. Walker ◽  
P. Waring ◽  
...  

2000 ◽  
Vol 53 (3) ◽  
pp. 285-293 ◽  
Author(s):  
Ian D. Goodwin ◽  
Christopher Zweck

AbstractThe Holocene sea-level high stand or “marine limit” in Wilkes Land, East Antarctica, reached ∼30 m above present sea level at a few dispersed sites. The most detailed marine limit data have been recorded for the Windmill Islands and Budd Coast at the margin of the Law Dome ice cap, a dome of the East Antarctic Ice Sheet (EAIS). Relative sea-level lowering of 30 m and the associated emergence of the Windmill Islands have occurred since 6900 14C (corr.) yr B.P. Numerical modeling of the Earth's rheology is used to determine the glacio-isostatic component of the observed relative sea-level lowering. Glaciological evidence suggests that most of EAIS thickening occurred around its margin, with expansion onto the continental shelf. Consequently, a regional ice history for the last glacial maximum (LGM) was applied in the glacio-isostatic modeling to test whether the observed relative sea-level lowering was primarily produced by regional ice-sheet changes. The results of the modeling indicate that the postglacial (13,000 to 8000 14C yr B.P) removal of an ice load of between 770 and 1000 m from around the margin of the Law Dome and adjacent EAIS have produced the observed relative sea-level lowering. Such an additional ice load would have been associated with a 40- to 65-km expansion of the Law Dome to near the continental shelf break, together with a few hundred meters of ice thickening on the adjoining coastal slope of the EAIS up to 2000 m elevation. Whereas the observed changes in relative sea level are shown to be strongly influenced by regional ice sheet changes, the glacio-isostatic response at the Windmill Islands results from a combination of regional and to a lesser extent, Antarctic-wide effects. The correspondence between the Holocene relative sea-level lowering interpreted at the margin of the Law Dome and the lowering interpreted along the remainder of the Wilkes Land and Oates Land coasts (105°–160° E) suggests that a similar ice load of up to 1000 m existed along the EAIS margin between Wilkes Land and Oates Land.


Author(s):  
MdDidarul Islam, Ashiqur Rahaman, Aboni Afrose

This study was based on determining concentration of essential and toxic heavy metal in coconut water available at a local Hazaribagh area in Dhaka, Bangladesh. All essential minerals, if present in the drinking water at high concentration or very low concentration, it has negative actions. In this study, fifteen samples and eight heavy metals were analyzed by Atomic Absorption Spectroscopy (AAS) method which was followed by wet ashing digestion method. The concentration obtained in mg/l were in the range of 0.3 to 1.5, 7.77 to 21.2, 0 to 0.71, 0 to 0.9, 0 to 0.2, 0.9 to 17.3, 0.1 to 0.9, 0 to 0.9 and 0 to 0.7 for Fe, Ni, Cu, Cd, Cr, Zn, Pb and Se respectively. From this data it was concluded that any toxic heavy metals like Cd, Cr, Pb and Ni exceed their toxicity level and some essential nutrients were in low concentration in those samples. 


2017 ◽  
Vol 1 ◽  
pp. 264
Author(s):  
Md Didarul Islam ◽  
Ashiqur Rahaman ◽  
Fahmida Jannat

This study was based on to determine the concentration of macro and micro nutrients as well as toxic and nontoxic heavy metals present in the chicken feed available in Dhaka city of Bangladesh. All macro nutrients, if present in the feed at high concentration have some adverse effect, at the same time if this nutrient present in the feed at low concentration this have some adverse effect too. So that this nutrient level should be maintained at a marginal level. On the other side toxic heavy metals if present in the feed at very low concentration those can contaminate the total environment of the ecosystem. In this study six brand samples (starter, grower, finisher and layer) which was collected from different renowned chicken feed formulation industry in Bangladesh. Those samples were prepared for analysis by wet ashing and then metals were determined by Atomic Absorption Spectroscopy. It was found that 27.7 to 68.4, 57.3 to 121.9, 0.21 to 4.1, 0.32 to 2.1, 0.11 to 1.58, 0.28 to 2.11 and 0.28 to 1.78 for zinc, iron, copper, mercury, cadmium, nickel and cobalt respectively. It was found that essential macro and micro nutrients were present in the feed in low concentration on the other side mercury was present in high concentration in the feed samples.


2017 ◽  
Vol 68 (10) ◽  
pp. 2363-2366
Author(s):  
Delia Nica Badea

The paper evaluates the presence and content of traces of heavy metals Hg, Pb, Ni, Cd (total forms) from coal and solid combustion products, the degree of transfer and accessibility in the area of influence of a lignite power plant. The content of toxic heavy metals in residues are characterized by RE Meiji [ 1 (Pb and Hg) and REMeij �1 (Ni and Cd) for the filter ash. Pb and Ni content in the soil exceeds normal values, and Pb exceeds and alert value for sensitive soils around the residue deposit (70.20 mg.Kg-1). The degree of accessibility of the metals in plants (TF), reported at the Khan reference value (0.5), indicates a significant bioaccumulation level for the metals: Cd (1.9) and Hg (0.6) inside the deposit; Cd (0.39) at the base of the deposit, Hg (0.8) in the area of the thermal power plant. The trace levels of heavy metals analyzed by GFAAS and CVAAS (Hg), indicates a moderate risk potential for food safety and quality of life in the studied area.


1992 ◽  
Vol 26 (9-11) ◽  
pp. 2149-2152 ◽  
Author(s):  
A. Grappelli ◽  
L. Campanella ◽  
E. Cardarelli ◽  
F. Mazzei ◽  
M. Cordatore ◽  
...  

Experiments on the real possibility of employing microorganisms to capture inorganic polluting substances, mainly heavy metals from urban and industrial wastes, are running using bacteria biomass. Many strains of Arthrobacter spp., gram-negative bacteria, diffused in the soil also inacondition of environmental stresses, have been proved to be particulary effective in heavy metal capture (Cd, Cr, Pb, Cu, Zn). The active and passive processes in accumulation of metals by bacteria were studied. Our experiments have been done on fluid biomass and on a membrane both for practical use and for an easy recovery.


Author(s):  
Varsha Shukla ◽  
Siddharth Kumar Das ◽  
Abbas Ali Mahdi ◽  
Shweta Agarwal ◽  
Ragini Alok ◽  
...  

BACKGROUND: Fibromyalgia syndrome (FMS) is an extra-articular rheumatological disease characterised by widespread chronic musculoskeletal pain. Metal-induced oxidative stress contributes to the severity of FMS. AIMS: First, this study evaluated the association between plasma levels of toxic heavy metals and essential metals with oxidative stress (OS) markers. Second, the OS markers and metal contents were correlated with the disease severity by assessing the Fibromyalgia Impact Questioner Revised (FIQR) and tender points (TP). METHOD: A total of 105 FMS patients and 105 healthy controls of similar age and sex were recruited. OS parameter such as lipid peroxidation (LPO), protein carbonyl group (PCG), nitric oxide (NO) and essential metals such as zinc (Zn), magnesium (Mg), manganese (Mn), copper (Cu) and toxic heavy metals such as aluminium (Al), arsenic (As), lead (Pb) were estimated. RESULTS: Levels of LPO, PCG, NO (p< 0.001) and Cu, Mn, and Al (p< 0.001), were significantly higher, and Mg (p< 0.001) and Zn (p< 0.001) were significantly lower in patients compared to controls. A positive association was observed between OS parameters, FIQR and TP with Cu, Al and Mn. A significant negative association was observed between Zn and Mg with FIQR, TP and OS parameters. CONCLUSION: Heavy metals such as Al induce OS parameters and decrease the levels of essential trace elements such as Mg and Zn, which may be responsible for the severity of FMS.


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