scholarly journals Characterization of calf liver Cu,Zn-metallothionein: naturally variable Cu and Zn stoichiometries

1996 ◽  
Vol 317 (2) ◽  
pp. 389-394 ◽  
Author(s):  
Pu CHEN ◽  
Patrick ONANA ◽  
C. Frank SHAW ◽  
David H. PETERING
Keyword(s):  
Metal Binding ◽  
Protein Concentration ◽  
Copper Ions ◽  
Atomic Absorption Spectrophotometry ◽  
Cu Content ◽  
Complementary Method ◽  
Absorption Spectrophotometry ◽  
Sulphydryl Groups ◽  
Ellman's Reagent

Cu,Zn-metallothioneins were purified from bovine calf liver in order to examine the stoichiometry of metal binding to the protein. Copper and zinc analyses were carried out by atomic absorption spectrophotometry. Consistent quantitative thiolate analyses were obtained spectrophotometrically with Ellman's reagent and amperometrically with phenylmercuric acetate. These were used to define protein concentration. A complementary method to assess the sum of the thiol and Cu(I) content of metallothionein involved titration of the reducing equivalents of the protein with ferricyanide. The stoichiometry of reaction was consistent with the oxidation of all the sulphydryl groups to disulphides and all of the bound Cu from the cuprous to the cupric oxidation state. According to these methods, total numbers of zinc plus copper ions bound to metallothionein isolated from a number of calf livers centred on about 7, 10–12, or 15 g-atoms of metal per mol of protein. The reactivity of ferricyanide and 4,7-phenylsulphonyl-2,9-dimethyl-1,10-phenanthroline (BCS) with Cu,Zn-metallothioneins of various metal ratios was assessed. Zinc metallothionein reacted almost entirely in two slow steps with ferricyanide. As the Cu content of the protein increased, the fraction of reaction occurring in the time of mixing increased in parallel. BCS was able to remove 70–80% of metallothionein-bound Cu as Cu(I). The rest was resistant to reaction.

Use of Animal Proteins to Limit Leaching of Active Copper Ions Preservatives from Treated Wood

Holzforschung ◽  
2003 ◽  
Vol 57 (6) ◽  
pp. 593-596 ◽  
Author(s):  
B. Mazela ◽  
I. Polus-Ratajczak
Keyword(s):  
Protein Denaturation ◽  
Copper Ions ◽  
Water Solution ◽  
Treated Wood ◽  
Atomic Absorption Spectrophotometry ◽  
Animal Blood ◽  
Protein Utilization ◽  
Solubility In Water ◽  
Absorption Spectrophotometry ◽  
Spray Dried

Summary The concept of animal protein utilization aiming to reduce leaching of treatment salts from wood was tested and verified. Animal proteins in the form of spray-dried animal blood plasma were used as an addition to the water solution of fungicidal salt or included in the solution for soaking pre-treated wood. The wood was subjected to thermal treatment which caused protein denaturation, a process which changes the proteins' spatial conformation and reduces their solubility in water. Scots pine wood (Pinus sylvestris L.) was treated with a water solution of copper sulfate using vacuum, vacuum-soaking and vacuum-pressure methods. The animal proteins were added to the treatment solutions or applied by soaking to samples pre-treated with the salt. After treatment, the samples were heated to 100°C. After suitable conditioning, the wood was subjected to leaching. The content of Cu2+ in the water extracts was determined by Atomic Absorption Spectrophotometry (AAS).

scholarly journals Isolation and Characterization of Chromate Resistant and Reducing Bacteria from Tannery Effluent of Chittagong, Bangladesh

1970 ◽  
Vol 17 ◽  
pp. 71-76
Author(s):  
M Fakruddin ◽  
Reaz Mohammad Mazumder ◽  
Towhida Khanom Tania ◽  
Saiful Islam ◽  
Meher Nigad Nipa ◽  
...  
Keyword(s):  
Atomic Absorption Spectrophotometry ◽  
Luria Bertani ◽  
Tannery Effluent ◽  
Bacterial Strains ◽  
E Coli ◽  
Absorption Spectrophotometry ◽  
Isolation And Characterization ◽  
Enzymatic Reduction ◽  
Reducing Bacteria

Context: Waste water containing Chromium (Cr6+) is by far the most important environmental challenge being faced. Objectives: The present study was planned on the isolation and characterization of chromate resistant and reducing bacterial strains in order to use them for detoxification of chromate.Materials and Methods: Water samples were collected to isolate microorganisms from tannery effluent of Baluchara, Chittagong and inoculated into Luria-Bertani medium with added Cr6+ as K2Cr2O7. The organisms have been identified and studied for Cr6+ reduction-ability in growth dependent manner.Results: A total of 35 isolates have been selected as potential organism belonging to the species of Moraxella (14.3%), Bacillus (11.43%), Streptococcus (25.72%), Staphylococcus (5.7%), Salmonella (12.3%), E. coli (13.3%), Enterobacter (11.3%), Hafnia alvei (2.45%) and Alcaligenes (3.5%). The selected isolates were able to tolerate at least 500 mg/l of Cr6+. The total Cr6+ concentration of the effluent sample analysed was found to be about 23.73 mg/l as determined by Atomic Absorption Spectrophotometry. Two of the isolates reduced 38% and 32% of Cr6+ added to the medium. Another 7 isolates showed Cr6+; reducing capability ranging from 18 to 22%.Conclusion: As the isolates have turned out to successfully reduce Cr6+ in this study, these can be used for the development of bioremediation process. Key words: Enzymatic reduction; Bioremediation; Chromium; Ecotoxicity; Tannery.DOI: 10.3329/jbs.v17i0.7104J. bio-sci. 17: 71-76, 2009

Polypyrrole/Alumina-Iron Oxide Nanocomposite for Removal of Copper Ions from Aqueous Solutions

2019 ◽  
Vol 969 ◽  
pp. 367-372
Author(s):  
P.N. Mary Lissy ◽  
G. Madhu ◽  
Roy M. Thomas
Keyword(s):  
Iron Oxide ◽  
Copper Ions ◽  
Freundlich Isotherm ◽  
Atomic Absorption Spectrophotometry ◽  
Adsorption Efficiency ◽  
Batch Mode ◽  
Absorption Spectrophotometry ◽  
Freundlich Adsorption Isotherm ◽  
Uv Visible ◽  
Temperature Time

The prepared Polypyrrole/Alumina-Iron oxide nanocomposite has showed 100% adsorption capacity in removing Copper ions from synthetic waste water. The nanocomposite was analyzed using SEM, TEM, FTIR, XRD and EDX. Batch mode adsorption studies were done to check the feasibility of prepared nanomaterial. Adsorption efficiency of the nanocomposite was measured using UV visible atomic absorption spectrophotometry and found 100 % at pH 8. Influence of inceptive Copper concentration, adsorbent dosage, time of contact, temperature, time with dosage, time and concentration were also tested to determine the optimum value in the uptake of Copper ions. Langmuir and Freundlich adsorption isotherm studies were analysed to understand the process of heavy metals adsorption and found best fitted to Freundlich Isotherm.

scholarly journals Risk Assessment of Heavy Metal Fe, Mn, Zn and Cu Intake by Consuming Herbal Tea Thyme

2021 ◽  
Vol 8 (2) ◽  
pp. 259-261
Author(s):  
Nisveta Softić ◽  
Halid Makić ◽  
Edisa Trumić ◽  
Husejin Keran ◽  
Melisa Ahmetović
Keyword(s):  
Heavy Metals ◽  
Risk Assessment ◽  
Hazard Index ◽  
Atomic Absorption Spectrophotometry ◽  
Herbal Tea ◽  
Mean Values ◽  
Cu Content ◽  
Absorption Spectrophotometry ◽  
Safe Food ◽  
Thymus Serpyllum

One of the most important public- health tasks is to provide hygienic and healthy food and water, which will not have harmful consequences for the health of consumers, and in this way a safe food trade is ensured, therefore protecting everyone in the chain from the producer to the consumer. This paper presents the concentrations of heavy metals Fe, Mn, Zn and Cu, obtained by atomic absorption spectrophotometry (AAS), from 5 samples of thyme infusion (lat. Thymus serpyllum), which can be found on the market of Travnik. Sample infusions were prepared by holding the filter bags in boiling deionized water for 10 minutes. Mean values of concentrations of these heavy metals were for Fe 0.0508 ± 0.0139 mg/kg, Mn 0.06 ± 0.0069 mg/kg, Zn 0.0436 ± 0.0147 mg/kg, while the Cu content was not detected in any infusion of the said tea. The risk assessment of the intake of tested heavy metals for the health of consumers, expressed through the Hazard Index (HI), which was <1, shows that the samples of analyzed teas are safe for consumption.

Comparison of liposome entrapment parameters by optical and atomic absorption spectrophotometry

1985 ◽  
Vol 5 (1) ◽  
pp. 1-5 ◽  
Author(s):  
Norma L. Yoss ◽  
Octavian Popescu ◽  
Victor I. Pop ◽  
Dorin Porutiu ◽  
Fred A. Kummerow ◽  
...  
Keyword(s):  
Atomic Absorption ◽  
Water Permeability ◽  
Atomic Absorption Spectrophotometry ◽  
Complete Characterization ◽  
Manganese Ion ◽  
Absorption Spectrophotometry ◽  
Paramagnetic Probe

Methods for the complete characterization of liposomes prepared by ether-injection are described in detail. The validity of atomic absorption spectrophotometry Ior measuring markers of trapped volume was checked by comparative determinations of markers with established optical spectrophotometrical methods. The favorable results usingl atomic absorption spectrophotometry to quantitate the marker Mn2+ are of particular relevance as manganese ion is also the paramagnetic probe in n.m.r, measurements of water permeability of lipo-somes; our results indicate that in such measurements no other marker need be incorporated.

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