A modification of the method using cellulose overlay agar to isolate and purify cellulolytic cytophagas from enrichment culture

1992 ◽  
Vol 38 (7) ◽  
pp. 687-689 ◽  
Author(s):  
R. A. Drijber ◽  
W. B. McGill
Keyword(s):  
Key Words ◽  
Enrichment Culture ◽  
Soil Samples ◽  
Existing Problems ◽  
Enrichment Cultures ◽  
Pure Cultures ◽  
Back Door ◽  
Agar Surface ◽  
Agar Method

We report here on a modification of the cellulose overlay agar method for isolating and purifying cellulolytic cytophagas from enrichment cultures. We call it the "back-door" method, and it overcomes two existing problems. First, it prevents recontamination with organisms growing on the agar surface. Second, it permits purification of cellulolytic cytophagas that are unable to utilize glucose or that are accompanied by a rapidly growing contaminant with spreading habit. Pure cultures of cellulolytic cytophagas were obtained from five enrichment cultures of nine soil samples examined. Two limitations are that (i) the cytophaga must be able to penetrate the overlay and (ii) some noncellulolytic cytophagas may also penetrate the overlay to yield cocultures. In conclusion, the back-door method can be used both to isolate and purify cellulolytic cytophagas from soils, using only a cellulose-based medium. Key words: back-door method, cellulolytic cytophagas, cellulose overlay agar, cellulolysis.

scholarly journals Identifying Hidden Viable Bacterial Taxa in Tropical Forest Soils Using Amplicon Sequencing of Enrichment Cultures

Biology ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 569
Author(s):  
Chakriya Sansupa ◽  
Sara Fareed Mohamed Wahdan ◽  
Terd Disayathanoowat ◽  
Witoon Purahong
Keyword(s):  
Bacterial Community ◽  
Forest Soil ◽  
Culture Media ◽  
Enrichment Culture ◽  
Sequence Similarity ◽  
Illumina Miseq ◽  
Amplicon Sequencing ◽  
Soil Samples ◽  
Enrichment Cultures ◽  
Total Community

This study aims to estimate the proportion and diversity of soil bacteria derived from eDNA-based and culture-based methods. Specifically, we used Illumina Miseq to sequence and characterize the bacterial communities from (i) DNA extracted directly from forest soil and (ii) DNA extracted from a mixture of bacterial colonies obtained by enrichment cultures on agar plates of the same forest soil samples. The amplicon sequencing of enrichment cultures allowed us to rapidly screen a culturable community in an environmental sample. In comparison with an eDNA community (based on a 97% sequence similarity threshold), the fact that enrichment cultures could capture both rare and abundant bacterial taxa in forest soil samples was demonstrated. Enrichment culture and eDNA communities shared 2% of OTUs detected in total community, whereas 88% of enrichment cultures community (15% of total community) could not be detected by eDNA. The enrichment culture-based methods observed 17% of the bacteria in total community. FAPROTAX functional prediction showed that the rare and unique taxa, which were detected with the enrichment cultures, have potential to perform important functions in soil systems. We suggest that enrichment culture-based amplicon sequencing could be a beneficial approach to evaluate a cultured bacterial community. Combining this approach together with the eDNA method could provide more comprehensive information of a bacterial community. We expected that more unique cultured taxa could be detected if further studies used both selective and non-selective culture media to enrich bacteria at the first step.

scholarly journals Inhibition of Nitrifiers and Methanotrophs from an Agricultural Humisol by Allylsulfide and Its Implications for Environmental Studies

1999 ◽  
Vol 65 (6) ◽  
pp. 2461-2465 ◽  
Author(s):  
Josh D. Neufeld ◽  
Roger Knowles
Keyword(s):  
Methane Oxidation ◽  
Enrichment Culture ◽  
Environmental Studies ◽  
Ammonia Monooxygenase ◽  
Enrichment Cultures ◽  
Pure Cultures

ABSTRACT Allylsulfide, an inhibitor of ammonia monooxygenase, was tested to determine its ability to inhibit nitrification and methane oxidation in pure cultures, in agricultural humisol enrichment cultures, and in humisol slurries. We confirmed that allylsulfide is a differential inhibitor of cultures of nitrifiers and methanotrophs at concentrations of 1 and 200 μM, respectively, which result in 50% inhibition. However, although a nitrifying enrichment culture added to sterilized humisol was inhibited 50% by 4 μM allylsulfide, 500 μM allylsulfide was necessary for 50% inhibition of the endogenous nitrifying activity in nonsterile humisol. We concluded that native nitrifiers were protected, possibly by being in colonial aggregates or sheltered microenvironments.

EXTRACTION OF BORON FROM CSSC REFERENCE SOILS BY HOT WATER, DILUTE CaCl2 AND MANNITOL-CaCl2 SOLUTIONS

1986 ◽  
Vol 66 (2) ◽  
pp. 377-381 ◽  
Author(s):  
P. A. SCHUPPLI
Keyword(s):  
Key Words ◽  
Soil Samples ◽  
Water Soluble ◽  
Hot Water ◽  
Distilled Water ◽  
Background Color ◽  
Color Development ◽  
Reference Soil ◽  
Highly Correlated

Soils were extracted by hot water, dilute CaCl2, and by mannitol-CaCl2 solutions and boron was determined by either azomethine-H or the curcumin method. Results were strongly method dependent; in particular results by the simplest method, mannitol-CaCl2, were generally lower and not highly correlated (r = 0.64) with those by the recommended procedure. This procedure involves extraction with hot distilled H2O (2:1 solution:soil), centrifugation, filtration, color development with azomethine-H and correction for background color. Extractable boron values by this procedure ranged from 0.1 to 1.4 mg kg−1. Background color can be further reduced by the substitution of 0.02 M CaCl2 for distilled water. Key words: CSSC reference soil samples, hot-water-soluble boron

Different types of manipulation in sport

2021 ◽  
Vol 66 (05) ◽  
pp. 109-113
Author(s):  
Hilal Mehti oğlu Abbasov ◽  
Keyword(s):  
Young People ◽  
Key Words ◽  
Drug Addiction ◽  
Sports Betting ◽  
Existing Problems ◽  
Sports Gambling ◽  
Different Types

Athletes are not roulette chips, but sports gambling treats them as such. If the dangers of state sponsored sports betting are not confronted, the character of sports and youngsters’ view of them could be seriously threatened… just as legalizing drugs would lead to increased drug addiction, legalizing sports gambling would aggravate the problems associated with gambling. As a society, we cannot afford this result, and… legalizing sports gambling would encourage young people to participate in sports to win money. They would no longer love the game for the purity of the experience. Key words: major manipulations, harmful aspects, existing problems, legalizing sports gambling, ethics of sports

An Improved Screening Method for the Detection and Isolation of Escherichia coli 0157:H7 From Meat, Incorporating the 3M Petrifilm™ Test Kit - HEC - for Hemorrhagic Escherichia coli 0157:H7

1990 ◽  
Vol 53 (11) ◽  
pp. 936-940 ◽  
Author(s):  
ANITA J. G. OKREND ◽  
BONNIE E. ROSE ◽  
RICHARD MATNER
Keyword(s):  
Escherichia Coli ◽  
Screening Program ◽  
Enrichment Culture ◽  
Screening Method ◽  
Meat Sample ◽  
E Coli ◽  
Enrichment Cultures ◽  
Poultry Products ◽  
Test Kit ◽  
Cooked Meat

A screening method was devised incorporating a commercially available reactive disc blot ELISA for Escherichia coli 0157 antigen, into a cultural screening program for the isolation of E. coli 0157:H7 from meat and poultry products. The method includes the inoculation of a raw or cooked meat sample into an enrichment broth, incubation with shaking at 37°C for 6 to 8 h, followed by inoculation of 3M Petrifilm™ E. coli Count plates with dilutions of the enrichment culture. The Petrifilm plates were incubated at 42°C for 18 h and tested for the presence of the 0157 antigen. The enrichment cultures were reincubated static at 35°C after the initial shaken incubation. Isolation was attempted from the positive Petrifilm plates by both a direct picking and streaking method and by the 3M Prompt™ isolation method. Isolation also was attempted from the 24-h enrichment cultures by spread plating serial dilutions on 150 × 15 mm MacConkey sorbitol agar (MSA) and MSA with 5-bromo-4-chloro-3-indoxyl-β-D-glucuronic acid cyclohexylammonium salt (BCIG). This fast and efficient screening procedure identifies negative and presumptive positive samples in 26–28 h. Isolation and confirmation of the presumptive positive isolates require an additional 3 to 4 d.

Magnetic susceptibility of Gleysolic and Chernozemic soils in Saskatchewan

2002 ◽  
Vol 82 (2) ◽  
pp. 191-199 ◽  
Author(s):  
E. de Jong
Keyword(s):  
Magnetic Susceptibility ◽  
Key Words ◽  
Soil Samples ◽  
Sand Content ◽  
Poorly Drained Soils ◽  
Extractable Iron

In Saskatchewan, Gleysolic and Chernozemic soils often are found close to each other in hummocky terrain. Magnetic susceptibility (χ) is known to be reduced in poorly drained soils compared to well-drained soils, and this study investigated the use of χ as an accessory criterion for identifying Gleysols. Archived soil samples from an area near Saskatoon were analyzed for χ and sand content, and where necessary for organic and inorganic C and oxalate (Feo) and dithionite (Fed) extractable iron. The lowest χ values were found in Humic Luvic Gleysols and the highest in Dark Brown Chernozems; Rego and Orthic Gleysols and Rego Humic Gleysols had χ values that overlapped those of the Dark Brown Chernozems. Within the upper 50 cm of the profile, all Gleysols except the Rego Humic Gleysol had at least one horizon with %chi; less than 150 × 10-9m3kg-1. The χ of the A and B horizons was negatively correlated to their Feo/Fed ratios, and not correlated to their sand content. The χ of the deep tills was positively correlated to sand content, and not correlated to Feo/Fed ratio. It appears that χ may be as useful as the Feo/Fed ratio for assisting in classifying Gleysols. Key words: Magnetic susceptibility, Gleysols, Chernozems, Feo, Fed, CaCo3

Metabolism of carbaryl and carbofuran by soil-enrichment and bacterial cultures

1984 ◽  
Vol 30 (12) ◽  
pp. 1458-1466 ◽  
Author(s):  
B. S. Rajagopal ◽  
V. R. Rao ◽  
G. Nagendrappa ◽  
N. Sethunathan
Keyword(s):  
Enrichment Culture ◽  
Side Chain ◽  
Bacillus Sp ◽  
Mineral Salts ◽  
Prolonged Incubation ◽  
Soil Enrichment ◽  
Enrichment Cultures ◽  
Hydrolysis Products ◽  
Carbamate Insecticides ◽  
Major Route

Metabolism of side chain and ring 14C-labelled carbaryl and carbofuran in a mineral salts medium by soil-enrichment cultures and a Bacillus sp. was studied. A change in the substrate of the medium from carbaryl to carbofuran led to a marked shift in the dominant bacterium from Bacillus sp. to Arthrobacter sp. although carbaryl-enrichment culture was the primary inoculum in both media. Hydrolysis was the major route of microbial degradation of both carbamate insecticides. During carbaryl degradation by enrichment cultures and Bacillus sp., 1-naphthol and 1,4-naphthoquinone accumulated in the medium. Of the three metabolites formed from carbofuran, 3-hydroxycarbofuran and 3-ketocarbofuran were further metabolized rapidly, while carbofuran phenol was resistant to further degradation. Evolution of 14CO2 and other gaseous 14C-labelled products from both side chain and ring labels was negligible. This and slow degradation of the hydrolysis products led to significant accumulation of 14C in the medium even after prolonged incubation.

Copper Recovery by Bioleaching of Chalcopyrite: A Microcalorimetric Approach for the Fast Determination of Bioleaching Activity

2013 ◽  
Vol 825 ◽  
pp. 322-325
Author(s):  
Beate Krok ◽  
Axel Schippers ◽  
Wolfgang Sand
Keyword(s):  
Enrichment Culture ◽  
Sulfide Oxidation ◽  
Exothermic Reaction ◽  
Metal Sulfide ◽  
Copper Recovery ◽  
Heat Output ◽  
Low Grade ◽  
Non Invasive ◽  
Pure Cultures ◽  
Invasive Method

Low grade copper ores containing chalcopyrite are increasingly used for copper recovery via biomining. Since metal sulfide oxidation is an exothememic process, bioleaching activity can be measured due to the heat output by microcalorimetry, which is a non-destructive and non-invasive method. The bioleaching activity of pure cultures ofSulfolobus metallicus,Metallosphaera hakonensisand a moderate thermophilic enrichment culture on high grade chalcopyrite was evaluated. Chalcopyrite leaching by microorganisms showed a higher copper recovery than sterile controls. Chemical chalcopyrite leaching by acid produced heat due to the exothermic reaction, the heat output was increased while metal sulfide oxidation by microorganisms.

A SOIL SAMPLING PROCEDURE FOR MICROMORPHOLOGICAL STUDIES

1987 ◽  
Vol 67 (3) ◽  
pp. 693-695 ◽  
Author(s):  
K. C. WIRES ◽  
B. H. SHELDRICK
Keyword(s):  
Key Words ◽  
Thin Section ◽  
Mineral Soil ◽  
Sampling Procedure ◽  
Soil Samples ◽  
Soil Sampling ◽  
Sampling System ◽  
Undisturbed Soil

An inexpensive, lightweight adjustable hydraulic sampling system is described for obtaining "undisturbed" Kubiena box samples, in relatively stone-free mineral soil, for thin-section preparation. Key words: Hydraulic sampling, undisturbed soil samples, thin section

TOTAL FLUORINE IN CSSC REFERENCE SOIL SAMPLES

1985 ◽  
Vol 65 (3) ◽  
pp. 605-607 ◽  
Author(s):  
P. A. SCHUPPLI
Keyword(s):  
Nitric Acid ◽  
Acid Solution ◽  
Key Words ◽  
Nitric Acid Solution ◽  
Soil Samples ◽  
Solution Technique ◽  
Reference Soil ◽  
Lithium Metaborate ◽  
Canadian Soils ◽  
Fluoride Electrode

Total fluorine was measured in a variety of Canadian soils using the lithium metaborate-nitric acid solution technique in conjunction with the fluoride electrode. Total fluorine ranged from 90 to 1000 mg∙kg−1. Key words: Soil fluorine analysis, fluoride electrode, CSSC reference soil samples

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