Contact-bioleaching mechanism of Ni and Co from sulfide concentrate at neutral pH by heterotrophic bacteria

2018 ◽  
Vol 35 (4) ◽  
pp. 221-229
Author(s):  
X. Cui ◽  
Q. Gu ◽  
X. Liu ◽  
J. Wen ◽  
A. Lu ◽  
...  
Keyword(s):  
Heterotrophic Bacteria ◽  
Neutral Ph ◽  
Sulfide Concentrate

A study of field drain ochre deposits. 2. The distribution of micro-organisms

1987 ◽  
Vol 108 (2) ◽  
pp. 347-351 ◽  
Author(s):  
I. Ap Dbwi ◽  
D. B. Johnson ◽  
W. I. Kelso
Keyword(s):  
Thiobacillus Ferrooxidans ◽  
Heterotrophic Bacteria ◽  
Drainage Water ◽  
Low Ph ◽  
Filamentous Bacteria ◽  
England And Wales ◽  
Neutral Ph ◽  
Wide Range ◽  
Water Ph ◽  
Micro Organisms

SummarySheathed filamentous bacteria,Leptothrixspp. andGallionellaspp., were observed in ochre samples from sites in England and Wales.Thiobacillus ferrooxidanswas found in acidic samples (pH < 4·0) and in ochre from drainage water of near neutral pH suggesting that it can contribute to ochre formation over a wide range of drainage water pH, Heterotrophic bacteria capable of growing in artificial media of low pH and complexdegrading heterotrophic bacteria were also isolated. Some ochre deposits could be described as either pyritic or filamentous but the majority of samples fell between these extremes and had various combinations ofT. ferrooxidans, sheathed filamentous bacteria and other heterotrophic bacteria.

Examination of Rabbit Fc Crystals

1968 ◽  
Vol 26 ◽  
pp. 140-141
Author(s):  
J. P. Robinson ◽  
P. G. Lenhert
Keyword(s):  
Molecular Weight ◽  
Flat Plate ◽  
Phosphate Buffer ◽  
Asymmetric Unit ◽  
X Ray Diffraction ◽  
X Ray ◽  
Neutral Ph ◽  
Small Crystals ◽  
Carbon Coated ◽  
Diffraction Patterns

Crystallographic studies of rabbit Fc using X-ray diffraction patterns were recently reported. The unit cell constants were reported to be a = 69. 2 A°, b = 73. 1 A°, c = 60. 6 A°, B = 104° 30', space group P21, monoclinic, volume of asymmetric unit V = 148, 000 A°3. The molecular weight of the fragment was determined to be 55, 000 ± 2000 which is in agreement with earlier determinations by other methods.Fc crystals were formed in water or dilute phosphate buffer at neutral pH. The resulting crystal was a flat plate as previously described. Preparations of small crystals were negatively stained by mixing the suspension with equal volumes of 2% silicotungstate at neutral pH. A drop of the mixture was placed on a carbon coated grid and allowed to stand for a few minutes. The excess liquid was removed and the grid was immediately put in the microscope.

Reaction of Acetaldehyde with Human Platelets

1992 ◽  
Vol 67 (01) ◽  
pp. 126-130 ◽  
Author(s):  
Olivier Spertini ◽  
Jacques Hauert ◽  
Fedor Bachmann
Keyword(s):  
Platelet Aggregation ◽  
Inhibitory Action ◽  
Ex Vivo ◽  
Platelet Rich Plasma ◽  
Shape Change ◽  
Reaction Medium ◽  
Human Platelets ◽  
Membrane Glycoproteins ◽  
Neutral Ph

SummaryPlatelet function defects observed in chronic alcoholics are not wholly explained by the inhibitory action of ethanol on platelet aggregation; they are not completely reproduced either in vivo by short-term ethanol perfusion into volunteers or in vitro by the addition of ethanol to platelet-rich plasma. As acetaldehyde (AcH) binds to many proteins and impairs cellular activities, we investigated the effect of this early degradation product of ethanol on platelets. AcH formed adducts with human platelets at neutral pH at 37° C which were stable to extensive washing, trichloracetic acid hydrolysis and heating at 100° C, and were not reduced by sodium borohydride. The amount of platelet adducts formed was a function of the incubation time and of the concentration of AcH in the reaction medium. At low AcH concentrations (<0.2 mM), platelet bound AcH was directly proportional to the concentration of AcH in the reaction medium. At higher concentrations (≥0.2 mM), AcH uptake by platelets tended to reach a plateau. The amount of adducts was also proportional to the number of exposures of platelets to pulses of 20 pM AcH.AcH adducts formation severely impaired platelet aggregation and shape change induced by ADP, collagen and thrombin. A positive correlation was established between platelet-bound AcH and inhibition of aggregation.SDS-PAGE analysis of AcH adducts at neutral pH demonstrated the binding of [14C]acetaldehyde to many platelet proteins. AcH adduct formation with membrane glycoproteins, cytoskeleton and enzymes might interfere with several steps of platelet activation and impair platelet aggregation.This in vitro study shows that AcH has a major inhibitory action on platelet aggregation and may account for the prolonged ex vivo inhibition of aggregation observed in chronic alcoholics even in the absence of alcoholemia.

Preparation, Stabilization and Some Properties of Purified Human Plasmin*

1964 ◽  
Vol 11 (01) ◽  
pp. 075-084 ◽  
Author(s):  
Daniel L Kline ◽  
Jacob B Fishman ◽  
Keyword(s):  
Plasminogen Activator ◽  
Stable Form ◽  
Neutral Ph ◽  
The Stability ◽  
And Storage

Summary1. Lysine increased the solubility, decreased the SK requirement and increased the stability of plasmin prepared from purified plasminogen by SK activation.2. A procedure is presented for the rapid and quantitative conversion of plasminogen to plasmin and storage of the plasmin in stable form at neutral pH as a lyophilized powder.3. Approximately 10% for the plasminogen molecule was split off during its activation. No carbohydrate was lost.4. The plasmin isolated was homogeneous in the ultracentrifuge at pH 2.5 and was quantitatively convertible to plasminogen activator by the addition of SK.

Fibrinolytic Activity of Lung and Spleen Extracts Observed in Conventional but not in Germ-Free Rats

1979 ◽  
Vol 42 (02) ◽  
pp. 726-733 ◽  
Author(s):  
Utako Okamoto ◽  
Jun-ichiro Yamamoto ◽  
Yoko Nagamatsu ◽  
Noboru Horie
Keyword(s):  
Serine Protease ◽  
Plasminogen Activator ◽  
Fibrinolytic Activity ◽  
Iodoacetic Acid ◽  
Thrombin Inhibitor ◽  
Rat Tissues ◽  
Germ Free ◽  
Neutral Ph ◽  
Tissue Extracts

SummaryProtease-like activity which split plasminogen-free fibrin was demonstrated in 2 M KSCN extracts of the lung and spleen of conventional rats. The activity was virtually undetectable in tissue extracts from germ-free rats. The extracts from the conventional rat tissues split fibrin and fibrinogen remarkably at neutral pH, but not casein, when examined using fibrin, fibrinogen-agar and casein-agar plates. The fibrinolytic activity was inhibited by STI and DFP, indicating a serine protease nature. The activity was not inhibited by TLCK, t-AMCHA or dansyl-L-arginine-methylpiperidine amide (a selective synthetic thrombin inhibitor, OM189). It was neither activated nor inhibited by cysteine, KCN or iodoacetic acid. The results obtained indicate that the protease-like activity of the lung and spleen extracted with 2 M KSCN from conventional rats has properties which differ from those of trypsin, plasmin, plasminogen-activator, thrombin, and cathepsin A, B and C.

Fungicidal and Bactericidal Activity of the Alkyl-Substituted Guanidine-Containing Oligomers

2020 ◽  
Vol 82 (6) ◽  
pp. 54-63
Author(s):  
M.Ya. Vortman ◽  
◽  
Yu.B. Pysmenna ◽  
A.I. Chuenko ◽  
D.R. Abdulina ◽  
...  
Keyword(s):  
Heterotrophic Bacteria ◽  
Trichoderma Viride ◽  
Rhodococcus Erythropolis ◽  
Biological Action ◽  
Molar Ratio ◽  
Diffusion Method ◽  
Klebsiella Pneumonia ◽  
Alkyl Bromides ◽  
Base Form ◽  
Two Stages

Biocides are widely used in medicine and various industries to protect against a number of harmful microorganisms. Organic quaternary ammonium and guanidine-containing compounds, the biological action of which is based on membrane-toxic properties, are used as bactericidal preparations. The aim of this work was to study the bactericidal and fungicidal activities of the synthesized oligomeric alkylsubstituted guanidinium bromides with different radicals -C3H7, -C7H15, -C10H21, against different isolates of heterotrophic bacteria and microscopic fungi. Methods. The synthesis of alkyl-substituted guanidiniumcontaining oligomers was performed in two stages. In the first stage, alkyl-substituted guanidine was obtained by the reaction of guanidine, previously converted by alkali from the salt form to the base form by the base and alkyl bromides (Alk=-C3H7 (propyl), -C7H15 (heptyl), -C10H21 (decyl)) in methanol at a temperature of 50°C and a molar ratio of 1:1. The second carried out the reaction between aromatic oligoepoxide DER-331 and alkyl-substituted guanidine in methanol at a temperature of 50°C for 2–3 hours and a molar ratio of 1:2. Bacteria were grown on meat-peptone agar for 48 hours at a temperature of 28±2°С. Test cultures of micromycetes were cultured on agar beer wort (6°B), incubated for 14 days in a thermostat at a temperature of 28±2°C. Antimicrobial activity of newly synthesized alkyl-substituted guanidinium-containing oligomers was determined by standard disco-diffusion method (method of disks on agar) and fungicidal activity was determined by the method of holes in agar. Results. Oligomeric alkylsubstituted guanidinium bromides with different radicals composed -C3H7, -C7H15, -C10H21- synthesized by the reaction of guanidine alkyl bromides with aromatic oligoepoxydes. It was found that alkyl-substituted guanidinium-containing oligomers at a concentration of 1–3% inhibited the growth of Escherichia coli 475, Pseudomonas aeruginosa 465, Klebsiella pneumonia 479, Pseudomonas pseudoalcaligenes 109, Staphylococcus aureus 451, E. faecalis 422, Rhodococcus erythropolis 102, Bacillus subtilis 138 and most of the studied micromycetes – Aureobasidium pullulans F-41430, Paecilomyces variotii F-41432, Penicillium funiculosum F-41435, Penicillium ochrochloron F-41431, Scopulariopsis brevicaulis F-41434, Trichoderma viride F-41437, Candida albicans F-41441, Aspergillus flavus F-41442, Aspergillus niger F-41448, Penicillium sp. F-41447. Conclusions. Antimicrobial and fungicidal properties significantly depend on the length of the alkyl radical, with increasing of its length the diameter of the zone of bacterial and micromycetes growth retardation increases.10.15407/microbiolj82.06.054

MICROBES PARAMETERS OF WATER QUALITY FOR AQUACULTURE ON PARI ISLAND WATERS

2013 ◽  
Vol 5 (1) ◽  
Author(s):  
Lies Indah Sutiknowati
Keyword(s):  
Pathogenic Bacteria ◽  
Heterotrophic Bacteria ◽  
Total Coliform ◽  
Total Cell ◽  
Epifluorescence Microscopy ◽  
Coliform Bacteria ◽  
Total Density ◽  
Shellfish Aquaculture ◽  
Microbiological Parameters ◽  
Phosphate Nitrate

The objective of this research was to evaluate waters quality in Pari island waters for aquaculture purpose based on bacteriological information conducted in Mei and September 2011. Microbiological parameters analyzed were total density of bacteria for coliforms, E.coli, pathogenic, heterotrophic, halotoleran, phosphate-nitrate-ammonia breaker, and total cells. Method to analyze coliform bacteria was filtration, identification of pathogenic bacteria using biochemical test, density analises for heterotrophic bacteria, analises for phosphate-nitrate-ammonia breaker bacteria using pour plate, and total cell using Acridine Orange Epifluorescence Microscopy. Results showed that the abundance of total coliform cell was about 1000-7000 colony forming unit (cfu)/100 ml. The abundance of heterotrophic, halotolerant, phosphate-nitrate-ammonia bacteria in seawater was (3.6-4.3)x105 cfu/ml, (1.1-1.3)x105 cfu/ml, (0.5-3.44)x103cfu/ml; and (3.6-6.7)x105 cfu/ml, (1.6-2.7)x105 cfu/ml, (0.6-5.22)x103 cfu/ml in sediment, respectively. The total cell of bacteria was (0.05-2.1)x107cells/ml. The dog-conch (Strombus turturella) and blood-clamps (Anadara granosa) can survive in Pari Island and there was a significant increase in sea grass litter with growth average of 0.67 mm/day and 0.90 mm/day. During snails and clamps growth, there were found several genus of pathogenic bacteria such as Salmonella, Vibrio, Aeromonas, Pseudomonas, Citrobacter, Proteus, Shigella, Hafnia, and Yersinia. The results showed that Pari island waters was suitable for developing shellfish aquaculture dog conch and blood clamps. Keywords: bacteria, parameter, shellfish, aquaculture.

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