Influence of Ions and Chelating Agents on the Haemolymphacetylcholinesterase of Mytilus edulis

1978 ◽  
Vol 33 (11-12) ◽  
pp. 851-858 ◽  
Author(s):  
Dettmar von Wachtendonk ◽  
Jutta Neef
Keyword(s):  
Enzyme Activity ◽  
Mytilus Edulis ◽  
Chelating Agents ◽  
Competitive Inhibition ◽  
Divalent Cations ◽  
Atomic Absorption Spectrophotometry ◽  
Ammonium Ions ◽  
Salicylic Aldehyde ◽  
Inorganic Cations ◽  
Absorption Spectrophotometry

By use of different inhibitors as well as atomic absorption spectrophotometry it has been shown that the haemolymph-acetylcholinesterase (E. c. 3.1.1.7) of the sea mussel Mytilus edulis is a me- talloprotein containing 2,95 Fe2+ -ions per subunit. All inhibitors used (1,10-phenanthroline, salicylic aldehyde, 2,2′-dipyridyl, 8-hydroxyquinoline) showed a non-competitive inhibition, which was not pH- dependent. Some divalent cations caused a marked increase of the enzyme activity, some heavy metals inhibited the enzyme almost completely; monovalent inorganic cations did not influence the enzyme at all. Besides NaF and Na2SiF6, which showed a non-competitive inhibition comparable to the inhibition observed with the chelating agents, and NaN3 , whose mode of action was not identifiable, no inhibition by different mono- and divalent inorganic anions was to be observed. Ammonium ions caused no enzyme inhibition, but length the inhibition power of substituted ammonium ions increased with an increasing C-chain. The influence of some organic solvents on the enzyme activity is demonstrated.

scholarly journals Dihydro-orotase from Clostridium oroticum. Purification and reversible removal of essential zinc

1985 ◽  
Vol 230 (1) ◽  
pp. 101-108 ◽  
Author(s):  
D W Pettigrew ◽  
R R Bidigare ◽  
B J Mehta ◽  
M I Williams ◽  
E G Sander
Keyword(s):  
Enzyme Activity ◽  
Amino Acid ◽  
Phosphate Buffer ◽  
Specific Activity ◽  
Zinc Content ◽  
Atomic Absorption Spectrophotometry ◽  
Kinetic Properties ◽  
Purification Procedure ◽  
Normal Complement ◽  
Absorption Spectrophotometry

A new purification procedure involving five column-chromatography steps is described for dihydro-orotase (L-5,6-dihydro-orotate amidohydrolase, EC 3.5.2.3) from Clostridium oroticum (A.T.C.C. 25750). The native purified enzyme is a dimer of Mr 102 000 and contains 4.0 +/- 0.3 g-atoms of zinc/mol of dimer. These observations agree with those reported previously [Taylor, Taylor, Balch & Gilchrist (1976) J. Bacteriol. 127, 863-873]. It is conclusively demonstrated that dihydro-orotase is a zinc metalloenzyme. Zinc is reversibly removed by treatment with chelators in phosphate buffer at pH 6.5, as demonstrated by atomic absorption spectrophotometry and decrease of enzyme activity. The specific activity is linearly dependent on zinc content. Addition of ZnSO4 to the chelator-treated enzyme results in regain of the normal complement of zinc and enzyme activity. Kinetic properties of the reconstituted enzyme are indistinguishable from those of the native enzyme. The amino acid composition of the homogeneous enzyme suggests that the zinc atoms occupy different environments.

scholarly journals ELEMENTAL ANALYSIS OF PRECIPITATES FORMED IN NUCLEI BY ANTIMONATE-OSMIUM TETROXIDE FIXATION

1972 ◽  
Vol 20 (7) ◽  
pp. 518-526 ◽  
Author(s):  
S. S. SPICER ◽  
A. A. SWANSON
Keyword(s):  
Lymph Nodes ◽  
Osmium Tetroxide ◽  
Divalent Cations ◽  
Atomic Absorption Spectrophotometry ◽  
Cervical Lymph Nodes ◽  
Isolated Nuclei ◽  
Absorption Spectrophotometry ◽  
Osmium Tetroxide Solution ◽  
Nuclear Activation ◽  
Nuclear Activation Analysis

Elements retained in cervical lymph nodes, isolated hepatic nuclei and salt-impregnated gels by fixation with antimonate- or pyrophosphate-containing and other osmium tetroxide solutions were assayed by nuclear activation analysis or by atomic absorption spectrophotometry. Salts preserved by the antimonate-osmium tetroxide fixative in lymph nodes, isolated nuclei and a KCl-enriched gel consisted almost entirely of potassium antimonate. The K+ in the precipitates in these specimens appeared to derive partially from that in the fixative solution and partially from that in the specimen. Salts preserved by the antimonate-osmium tetroxide fixative in an NaCl-supplemented gel consisted partly of potassium antimonate derived from the fixative as in unsupplemented gels and partly of sodium antimonate. The Na+ precipitated in this gel amounted to less than one-half that originally present. In comparison the pyrophosphate-osmium tetroxide solution retained higher levels of K+ in lymph nodes, nuclei and the KCl gel, but the potassium pyrophosphate was not evident as electron-opaque precipitates. The latter fixative was less effective in preserving Na+ in the NaCl gel. The pyrophosphate-containing fixative, which was about twice as efficient as the antimonate-containing solution in retaining the divalent cations, preserved 70% of the Mg++ and 100% of the Ca++ added to gels.

The Effect of Certain Chelating Compounds on the Urinary Excretion of Copper by the Rat: Observations on their Clinical Significance

1977 ◽  
Vol 53 (4) ◽  
pp. 317-320
Author(s):  
Kathleen Gibbs ◽  
J. M. Walshe
Keyword(s):  
Urinary Excretion ◽  
Atomic Absorption ◽  
Clinical Significance ◽  
Chelating Agents ◽  
Standard Dose ◽  
Atomic Absorption Spectrophotometry ◽  
Test Animal ◽  
Absorption Spectrophotometry ◽  
Chelating Compounds ◽  
Clinical Potential

1. A screening procedure is described to assess rapidly the clinical potential of chelating agents for the treatment of Wilson's disease. 2. Rats were used as the test animal; they were kept in metabolic cages and the urine was collected in copper-free containers. The compounds investigated were given by mouth as a standard dose of 100 mg. Copper was determined by atomic absorption spectrophotometry. 3. Basal urine copper excretion was 65·1 ± se 2·93 nmol/24 h (4·1 μg ± 0·185). After penicillamine this rose to 367·1 nmol and after trien to 305·9 nmol. 4. Certain compounds caused a reduction in the amount of copper excreted in the urine, probably by forming insoluble chelates with the metal, hence rendering it unavailable for excretion at the glomerulus.

scholarly journals Control of Ram Sperm Adenylate Cyclase by Divalent Cations

1988 ◽  
Vol 41 (3) ◽  
pp. 377 ◽  
Author(s):  
P PGoh ◽  
IG White
Keyword(s):  
Enzyme Activity ◽  
Adenylate Cyclase ◽  
Chelating Agents ◽  
Divalent Cations ◽  
Cyclase Activity ◽  
Adenylate Cyclase Activity ◽  
Simultaneous Addition ◽  
Ram Sperm ◽  
Sulfhydryl Compounds

The adenylate cyclase activity of ram sperm increased on freeze-thawing and the enzyme was stable at O�C. Its activity was stimulated by Mn2+, Zn2+, Co2+, Mg2+ and Ca2+ in descending order of activity. The enzyme was insensitive to fluoride when Mn2+ concentration was in excess. Mn2+_ stimulated enzyme activity was decreased by the simultaneous addition of Co2+, or Cd2+, or Ni2+, and particularly Cu2+. Sulfhydryl compounds (viz. dithiothreitol, glutathione, dithiocarbamate, 2- mercaptoethanol, ergothioneine and cysteine) and chelating agents (viz. D-penicillamine and 8-hydroxyquinoline) were effective, to varying degrees, in overcoming the inhibition by Cu2+. Ca2+ augmented the stimulatory effect of Mg2+, Co2+, Zn2+ and Mn2+ on enzyme activity.

Effects of cadmium on canine renal cortical adenylate cyclase

1987 ◽  
Vol 253 (3) ◽  
pp. F401-F407
Author(s):  
U. Lundberg ◽  
C. L. Milanes ◽  
N. Pernalete ◽  
J. R. Weisinger ◽  
N. E. Contreras ◽  
...  
Keyword(s):  
Enzyme Activity ◽  
Adenylate Cyclase ◽  
Competitive Inhibition ◽  
Partial Agonist ◽  
Divalent Cations ◽  
Dose Range ◽  
Cyclase Activity ◽  
Adenylate Cyclase Activity ◽  
Fourfold Increase ◽  
Dose Dependent

The present studies examine the effects of cadmium (Cd2+) on adenylate cyclase activity in basolateral renal cortical membranes from normal dogs. Cd2+, in the dose range of 1 to 200 microM caused a dose-dependent inhibition of adenylate cyclase activity due to competitive inhibition with respect to the allosteric activator Mg2+ (increase in the Kact for Mg2+ from 13.8 to 37.2 mM). In addition, increasing Cd2+ concentrations from 0 to 25 microM resulted in a purely competitive inhibition with respect to ATP. The Km for ATP increased from 61 to 128 microM. When Mn2+ at a concentration of 20 mM was substituted for Mg2+, Cd2+ maintained its inhibitory effect at concentrations lower than 25 microM. At higher concentrations it stimulated enzyme activity in a dose-dependent fashion. In the absence of other divalent cations Cd2+ was a potent stimulator of basal adenylate cyclase activity, far more potent than the physiological activator of the system Mg2+. Kact for Cd2+ was 1.0 mM (Kact for Mg2+ 20 mM), whereas the Vmax showed a fourfold increase compared with the Mg2+-stimulated membranes. However, under these conditions, synthetic bovine parathyroid hormone (1-34) or 5'-guanylylimidodiphosphate did not stimulate adenylate cyclase. It is concluded that Cd2+ behaves as a partial agonist in this system, due to its ability to form a new enzymatic substrate complex: Cd-ATP, which competes with the physiological substrate Mg-ATP at the catalytic site of the enzyme. In addition, Cd2+ in the absence of other divalent cation stimulates basal enzyme activity, presumably through interaction at an additional site, closely related to the allosteric metal regulatory site of this enzyme system.

scholarly journals Adsorption of some Metal Ions from Aqueous Solution on Iraqi Rice Bran and Its Relation to the Physical Properties of these Metal Ions

2014 ◽  
Vol 11 (4) ◽  
pp. 1604-1611
Author(s):  
Baghdad Science Journal
Keyword(s):  
Aqueous Solution ◽  
Adsorption Isotherm ◽  
Metal Ions ◽  
Rice Bran ◽  
Ionic Radius ◽  
Divalent Cations ◽  
Atomic Absorption Spectrophotometry ◽  
Waste Materials ◽  
Absorption Spectrophotometry ◽  
Adsorptive Behavior

Adsorption studies were carried out to test the ability of the Iraqi rice bran (Amber type) to adsorb some metals divalent cations (Cd2+, Co2+, Cu2+, Fe2+, Ni2+, Pb2+, and Zn2+) as an alternative tool to remove these pollutants from water. The Concentrations of these ions in water were measured using flame and flamless atomic absorption spectrophotometry techniques. The applicability of the adsorption isotherm on Langmuir or Freundlisch equation were tested and found to be dependent on the type of ions. The results showed different adsorptive behavior and different capacities of the adsorption of the ions on the surface of the bran. The correlation between the amounts adsorbed and different cation parameters including (electronegativity, ionic radius, and the second ionization potential) were tested. This study showed the applicability of bran, as a cheap and available waste materials, to remove different cations from solution.

Analysis of Lead Heavy Metal (Pb) Contamination on Matte Lipstick Preparations for Sale in Banda Aceh City Aceh Market

2020 ◽  
Vol 2 (1) ◽  
Author(s):  
Rizki Andalia ◽  
Mulia Aria Suzanni ◽  
Rini Rini
Keyword(s):  
Heavy Metal ◽  
Atomic Absorption ◽  
Atomic Absorption Spectrophotometry ◽  
The Body ◽  
Permissible Limit ◽  
The Sun ◽  
Absorption Spectrophotometry ◽  
Pb Contamination ◽  
Body Organ ◽  
Banda Aceh

Lipstick or lip dye is a cosmetic dose that serves to coloring, decorative the lips, as a moisturizing material and protect the lips from exposure the sun to provide optimum results. Lipstick should not contain chemicals such as lead (Pb) because the Pb is a heavy metal that is very dangerous when continuously used on the skin, because it will be absorbed into the blood and attack the body organ causing the onset of disease. According to BPOM that the lead rate on the lipstick does not exceed the permissible limit of 20 mg/kg or 20 ppm.This research aims to know the levels contained in the samples are 4 brands of matte lipstick that are sold in the Aceh market in Banda Aceh City with the method of atomic absorption spectrophotometry (AAS). The results showed that on the 4 brands of lipstick matte contain heavy metal lead (Pb) with a rate still qualified allowed by BPOM  is samples A, B, C, and D, respectively at 0.24 ppm; 0.10 ppm; 2.87 ppm and 1.32 ppm, so that the 4 brands of lipstick matte are still used.

Analisis Kandungan Mikroba, Formalin, dan Timbal (Pb) pada Tahu Sumedang yang Dijual Di Daerah Macet Cicurug, Ciawi, dan Cisarua Jawa Barat

2020 ◽  
Vol 6 (1) ◽  
pp. 087
Author(s):  
Rosy Hutami ◽  
M Fakih Kurniawan ◽  
Henna Khoerunnisa
Keyword(s):  
Content Analysis ◽  
Microbial Contamination ◽  
Atomic Absorption Spectrophotometry ◽  
Plate Count ◽  
Traffic Jam ◽  
Absorption Spectrophotometry ◽  
Traffic Jams ◽  
Total Plate Count ◽  
Microbial Analysis ◽  
Aas Method

Sumedang tofu is one of favorite foods for Indonesian society. But many sellers or producers are not aware to the food safety of sumedang tofu. The aims of this study were to analyze the microbial, formalin, and lead (Pb) contents in ready-to-eat sumedang tofu which were sold in traffic jams area in Cicurug, Ciawi, and Cisarua. The analysis were carried out by Total Plate Count (TPC) testing for microbial analysis, potassium permanganate reaction (KMnO4) testing for formaldehyde analysis, and atomic absorption spectrophotometry (AAS) method for lead content analysis in the samples. The results obtained for the microbial analysis were sumedang tofu that were sold in the traffic jam areas of Cicurug, Ciawi, and Cisarua contained contaminant above the treshold (1.4 x 105 colonies / gram to 2.2 x 105 colonies / gram of microbes). All of the samples of sumedang tofu were positive containing formaldehyde. Otherwise, there were no lead (Pb) content in all samples regarding to AAS analysis. This study concluded that the ready-to-eat sumedang tofu those were sold in traffic jam area in the Cicurug, Ciawi, and Cisarua were not suitable for consumption because it contained exceed microbial contamination and formalin which are harmful for human health.Keywords : formalin, microbes, sumedang tofu, lead, traffic jam

Assessment of heavy metals in tobacco of cigarettes commonly sold in Ethiopia

2019 ◽  
Author(s):  
Chem Int
Keyword(s):  
Heavy Metals ◽  
Trace Metals ◽  
Atomic Absorption Spectrophotometry ◽  
Epidemiological Studies ◽  
Cigarette Tobacco ◽  
Absorption Spectrophotometry ◽  
Wet Digestion ◽  
Metal Contents ◽  
Cu And Zn ◽  
Significant Flux

A significant flux of heavy metals, among other toxins, reaches the lungs through smoking. This study reports Cd, Pb, Cu and Zn contents in tobacco of 11 brands of cigarette commonly sold in Ethiopia. The heavy metals were determined by atomic absorption spectrophotometry after wet digestion of cigarette tobacco using HNO3 and H2O2. The concentration of trace metals in the cigarettes ranged (mean) (μg/g), Cd: 1.3−7.6 (2.48±0.32), Pb: 0.50−12.50 (6.24±2.2), Cu: 2.89−25.35 (13.70±4.12) and Zn: 24.40−62.55 (36.22±7.50) while Ni was not detected in all the eleven brands of cigarettes. Comparable levels of trace metals were obtained in the tobacco of both imported and Ethiopian cigarettes. The average trace metal contents of cigarettes available in Ethiopia were Cd 1.82±0.39, Pb 4.23±0.97, Cu 10.2±3.1 and Zn 28.2±7.8 μg/cigarette and a person who smokes 20 cigarettes per day is estimated to increase his/her daily Cd, Pb, Cu and Zn retention by approximately 0.036, 0.085, 0.204, 0.564 mg/day, respectively. The results indicate that smoking and exposure to cigarette smoke is a serious problem to be taken into account when carrying out epidemiological studies on human exposure to trace metals.

PENURUNAN KONSENTRASI LOGAM Pb2+ DAN Cd2+ PADA LIMBAH CAIR INDUSTRI SASIRANGAN DENGAN METODE FITOREMEDIASI

2015 ◽  
Vol 1 (1) ◽  
pp. 41
Author(s):  
Bella Santa Rossi ◽  
Paryanti Paryanti ◽  
Yuli Ristianingsih ◽  
Abubakar Tuhuloula
Keyword(s):  
Atomic Absorption ◽  
Atomic Absorption Spectrophotometry ◽  
Absorption Spectrophotometry

Pewarnaan pada proses produksi kain sasirangan menghasilkan limbah yang mengandung logam berat, diantaranya adalah timbal (Pb2+) dan kadmium (Cd2+). Penelitian ini bertujuan untuk mengetahui pengaruh proses fitoremediasi terhadap konsentrasi logam Pb2+ dan Cd2+ dari limbah cair industri sasirangan di Kalimantan Selatan, serta mengetahui pertambahan berat basah eceng gondok. Eceng gondok yang sudah dibersihkan dan diaklimatisasi ditanam dalam reaktor berisi larutan limbah dengan konsentrasi 3% (v/v); 9% (v/v); dan 15% (v/v). Sampel diambil setiap 2 hari sekali sebanyak 100 ml dan dianalisis menggunakan AAS (Atomic Absorption Spectrophotometry). Hasil penelitian ini menunjukkan bahwa konsentrasi logam Pb2+ dan Cd2+ dalam limbah setelah proses fitoremediasi terjadi penurunan. Kadar Pb2+ pada konsentrasi 3% (v/v) semula 0,197 ppm menjadi 0,062 ppm, pada konsentrasi 9% (v/v) semula 0,200 ppm menjadi 0,077 ppm dan untuk 15% (v/v) adalah 0,225 ppm menjadi 0,093 ppm. Sedangkan untuk Cd2+ konsentrasi 3% (v/v) semula 0,110 ppm menjadi 0,059 ppm, konsentrasi 9% (v/v) adalah 0,127 ppm menjadi 0,045 ppm dan untuk konsentrasi 15% (v/v) semula 0,144 ppm menjadi 0,047 ppm.

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