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- Author:
- Nielsen, Forrest H.
- Source:
- Handbook of metal-ligand interactions in biological fluids : bioinorganic medicine / edited by Guy Berthon pp. -
- Subject:
- ferredoxin hydrogenase; mineral metabolism; microbial physiology; nickel; acetate-CoA ligase; urease; nutrition physiology; coenzymes
- Handle:
- 10113/44996
- Author:
- Richard Volk; Clayton McAuliffe
- Source:
- Soil Science Society of America journal 1954 v.18 no.3 pp. 308-312
- ISSN:
- 0361-5995
- Subject:
- camels; cell walls; diurnal variation; enzyme activity; enzyme inhibition; greenhouses; leaf area; mature plants; meristems; nitrogen; nutrient uptake; phosphates; sand; sucrose; tobacco; uptake mechanisms; urea; urease
- Abstract:
- ... Single leaves of Dixie Bright 101 tobacco plants grown in sand culture in the greenhouse were sprayed with N¹⁵ labeled urea. Up to 5 mg. of the 15 mg. of nitrogen applied was absorbed by the leaf within 24 hours, and by 6 hours a portion of this nitrogen had been translocated to every plant part. One-half of the absorbed nitrogen was translocated from the sprayed leaf by 24 hours, chiefly to adjac ...
- DOI:
- 10.2136/sssaj1954.03615995001800030020x
- https://doi.org/10.2136/sssaj1954.03615995001800030020x
- Author:
- Smith, A.K.; Belter, P.A.; Anderson, R.L.
- Source:
- Journal of the American Oil Chemists' Society 1956 v.33 no.8 pp. 360-363
- ISSN:
- 0003-021X
- Subject:
- soybean products; urease; enzyme activity; analytical methods
- Abstract:
- ... A method which uses direct titration of ammonia as a measure of urease activity was modified for use in the assay of raw and of slightly denatured soybean meal. The modifications which were adopted were the use of glutathione, a presoaking of the sample for 30 min. at 40°C., and making of the assay at 40°C. Data on the urease activity of several varieties of soybeans, and for immature and frost-da ...
- Handle:
- 10113/30275
- DOI:
- 10.1007/BF02665111
- https://doi.org/10.1007/BF02665111
- Author:
- A. D. McLaren; R. A. Luse; J. J. Skujins
- Source:
- Soil Science Society of America journal 1962 v.26 no.4 pp. 371-377
- ISSN:
- 0361-5995
- Subject:
- Solanum lycopersicum; X-radiation; electrons; enzyme activity; gamma radiation; hydrolysis; irradiation; microorganisms; nutrients; plant growth; root systems; soil; soil enzymes; soil sterilization; tomatoes; toxicity; urease
- Abstract:
- ... As an introduction to the study of radiation-sterilized soil as a medium for microbial and plant growth, survival curves for microorganisms have been obtained with 5 and 9 Mev. electrons, hard X-ray and gamma radiation. For a given soil, bacterial survival curves with these radiations are almost superimposable, but they differ among soils. Bacterial numbers in soils approach zero at 2 Mrep. doses, ...
- DOI:
- 10.2136/sssaj1962.03615995002600040019x
- https://doi.org/10.2136/sssaj1962.03615995002600040019x
- Author:
- D. R. Keeney; J. M. Bremner
- Source:
- Soil Science Society of America journal 1967 v.31 no.3 pp. 317-321
- ISSN:
- 0361-5995
- Subject:
- ammonium; ammonium nitrogen; buffers; nitrates; nitrites; nitrogen; pH; potassium chloride; potassium phosphates; soil; steam distillation; titration; urea; urea nitrogen; urease
- Abstract:
- ... Two methods of determining urea in soils are described. In one (extraction-distillation method), the soil sample is extracted with 2M KCl (10 ml/g of soil) for 5 min, and an aliquot of the extract is treated with potassium phosphate buffer (pH 8.0) and urease for 2 hours at 30C to convert urea N to ammonium N. In the other (direct-distillation method), the soil sample is treated directly with pH 8 ...
- DOI:
- 10.2136/sssaj1967.03615995003100030011x
- https://doi.org/10.2136/sssaj1967.03615995003100030011x
- Author:
- P. G. Moe
- Source:
- Soil Science Society of America journal 1967 v.31 no.3 pp. 380-382
- ISSN:
- 0361-5995
- Subject:
- Zea mays; ammonia; ammonium; corn; enzyme activity; hydrolysis; leaching; liming materials; mulches; nitrification; nitrogen; sand; silt loam soils; soil enzymes; urea; urease; volatilization
- Abstract:
- ... Laboratory incubation experiments were conducted to determine whether nitrogen losses from urea could be reduced by manipulating the urease activity of the soil. The natural urease activity of Chalmers silt loam and Plainfield sand was modified directly by applications of either additional urease enzyme or an enzyme inhibitor and indirectly by applications of a decomposing mulch and liming materia ...
- DOI:
- 10.2136/sssaj1967.03615995003100030026x
- https://doi.org/10.2136/sssaj1967.03615995003100030026x
- Author:
- M. R. Roberge; R. Knowles
- Source:
- Soil Science Society of America journal 1968 v.32 no.4 pp. 518-521
- ISSN:
- 0361-5995
- Subject:
- Picea mariana; ammonia; cobalt; enzyme activity; gamma radiation; humus; irradiation; microorganisms; mineralization; nitrogen; organic horizons; radionuclides; urea; urea nitrogen; urease; Quebec
- Abstract:
- ... The activity of urease was studied in a black spruce (Picea mariana (Mill.) BSP.) surface organic horizon from Baie-Comeau, Quebec. Samples were sterilized by ⁶⁰Co radiation, incubated with urea for 8 hours at 20C and analyzed for ammonia. Urease activity decreased with an increase in humus decomposition. Field fertilization with 450 kg urea-N/ha 2 years prior to humus sampling increased the ureas ...
- DOI:
- 10.2136/sssaj1968.03615995003200040028x
- https://doi.org/10.2136/sssaj1968.03615995003200040028x
- Author:
- Blakeley, R.; Webb, E.C.; Zerner, B.
- Source:
- Biochemistry 1969 v.8 no.5 pp. 1984-1990
- ISSN:
- 0006-2960
- Subject:
- urease; assays; beans
- DOI:
- 10.1021/bi00833a031
- https://doi.org/10.1021/bi00833a031
- Author:
- Blakeley, R.L.; Hinds, J.A.; Kunze, H.E.; Webb, E.C.; Zerner, B.
- Source:
- Biochemistry 1969 v.8 no.5 pp. 1991-2000
- ISSN:
- 0006-2960
- Subject:
- acids; beans; hydroxamic acids; urease
- DOI:
- 10.1021/bi00833a032
- https://doi.org/10.1021/bi00833a032
- Author:
- Mustakas, G.C.; Albrecht, W.J.; McGhee, J.E.; Black, L.T.; Bookwalter, G.N.; Griffin, E.L.
- ISSN:
- 0003-021X
- Subject:
- enzyme inactivation; lipid content; soy flour; nitrogen content; inactivation temperature; peroxide value; free fatty acids; linoleate 13S-lipoxygenase; oxidative stability; water content; flavor; pH; rancidity; urease; heat treatment
- Abstract:
- ... Oxidation of soybean lipids catalyzed by lipoxidase was prevented by heat treatment of soybean meats, which were then ground to give a full-fat soy flour free of rancid odor and flavors. Our previous studies showed that lipids in cracked, dehulled, soybeans rapidly oxidized after the lipoxidase system was activated by increasing moisture content to 20%. A series of experiments are reported in whic ...
- Handle:
- 10113/31706
- DOI:
- 10.1007/BF02544982
- https://doi.org/10.1007/BF02544982
- Author:
- K. N. Paulson; L. T. Kurtz
- Source:
- Soil Science Society of America journal 1969 v.33 no.6 pp. 897-901
- ISSN:
- 0361-5995
- Subject:
- enzyme activity; loci; regression analysis; soil; soil colloids; soil enzymes; soil microorganisms; urea; urea nitrogen; urease
- Abstract:
- ... A model is proposed to determine the location of active urease in soil; that is, whether the urease was associated directly with soil microorganisms or free from microorganisms and adsorbed on the soil colloids. An indirect approach was used which consisted of making periodic measurements of urease activity during a period of time when the microbial population was undergoing change. Multiple regre ...
- DOI:
- 10.2136/sssaj1969.03615995003300060029x
- https://doi.org/10.2136/sssaj1969.03615995003300060029x
- Author:
- Gaylord M. Volk
- Source:
- Soil Science Society of America journal 1970 v.34 no.3 pp. 513-516
- ISSN:
- 0361-5995
- Subject:
- Pinus elliottii; ammonia; ammonium nitrogen; bark; burning; enzyme activity; hydrolysis; pellets; soil; soil sterilization; urea; urea nitrogen; urease
- Abstract:
- ... Gaseous loss of NH₃ from prilled urea, surface applied at 100 kg N/ha to undisturbed dry organic residue over moist soil under slash pine (Pinus elliottii Engelm. var. elliottii), averaged 4% in 7 days as compared with 2% for an area that was control-burned 5 weeks previous, and 5% for one from which loose debris had been removed. This was approximately equivalent to removal by burning. Residual u ...
- DOI:
- 10.2136/sssaj1970.03615995003400030042x
- https://doi.org/10.2136/sssaj1970.03615995003400030042x
- Author:
- K. N. Paulson; L. T. Kurtz
- Source:
- Soil Science Society of America journal 1970 v.34 no.1 pp. 70-72
- ISSN:
- 0361-5995
- Subject:
- enzyme activity; enzyme kinetics; microorganisms; soil; soil enzymes; urease
- Abstract:
- ... Application of the Michaelis-Menten equation to urease activity of soil showed that the Michaelis constant (Kₘ) changed with fluctuation in microbial population and thus with changes in the proportion of microbial and adsorbed urease. Regression of urease activity on number of ureolytic microorganisms permitted division of total urease activity into portions caused by microbial and adsorbed forms, ...
- DOI:
- 10.2136/sssaj1970.03615995003400010021x
- https://doi.org/10.2136/sssaj1970.03615995003400010021x
- Author:
- Bookwalter, G.N.; Mustakas, G.C.; Kwolek, W.F.; McGhee, J.E.; Albrecht, W.J.
- Source:
- Journal of food science 1971 v.36 no.1 pp. 5-9
- ISSN:
- 0022-1147
- Subject:
- soy flour; nitrogen content; food nutrient losses; shelf life; breadmaking quality; essential amino acids; nutritive value; oxidative stability; flavor; amino acid composition; extrusion; functional properties; urease; rancidity; extruded foods; analytical methods; enzyme activity
- Abstract:
- ... Full-fat soya flours prepared by the extrusion process were shown to have good nutritive value, flavour and stability. A flour cooked to a N solubility index (NSI) of 30 stored well, but the addition of tertiary butyl hydroquinone was necessary to prevent rancidity in flours cooked to 19 and 11 NSI values. The 30 NSI flour was more yellow than a commercial flour cooked to the same degree by a diff ...
- Handle:
- 10113/31617
- DOI:
- 10.1111/j.1365-2621.1971.tb02019.x
- https://doi.org/10.1111/j.1365-2621.1971.tb02019.x
- Author:
- R. G. Burns; A. H. Pukite; A. D. McLaren
- Source:
- Soil Science Society of America journal 1972 v.36 no.2 pp. 308-311
- ISSN:
- 0361-5995
- Subject:
- bentonite; enzyme activity; filtration; lignin; proteinases; proteolysis; salts; soil; soil enzymes; soil organic matter; temperature; urease
- Abstract:
- ... Urease activity in soil is persistent for long periods under low water, low temperature, and sterile regimes, and it has been suggested that some form of enzyme-protective mechanism exists in soil. Dublin soil was sonicated in water and extracted by adding a mixture of salts. Urease activity is associated with the organomineral complex thus obtained and is resistant to the activities of proteolyti ...
- DOI:
- 10.2136/sssaj1972.03615995003600020030x
- https://doi.org/10.2136/sssaj1972.03615995003600020030x
16. Effect of Storage Conditions on Activities of Urease, Invertase, Amylase, and Dehydrogenase in Soil
- Author:
- Sunil K. Pancholy; Elroy L. Rice
- Source:
- Soil Science Society of America journal 1972 v.36 no.3 pp. 536-537
- ISSN:
- 0361-5995
- Subject:
- Mollisols; ambient temperature; amylases; beta-fructofuranosidase; enzyme activity; soil enzymes; storage temperature; urease; Oklahoma
- Abstract:
- ... There were no significant decreases in the activities of urease, invertase, and amylase after 30 days' storage of an Oklahoma mollisol at 4C. However, storage at room temperature (21C) was unsatisfactory. Significant loss in activity was noted in the case of dehydrogenase after 15 and 30 days of soil storage at both 4C and room temperature. Fresh soil was used for assay of dehydrogenase. ...
- DOI:
- 10.2136/sssaj1972.03615995003600030046x
- https://doi.org/10.2136/sssaj1972.03615995003600030046x
- Author:
- Baker, E.C.; Mustakas, G.C.
- ISSN:
- 0003-021X
- Subject:
- heat inactivation; soy flour; sodium hydroxide; soybean oil; trypsin inhibitors; soy protein; linoleate 13S-lipoxygenase; soybeans; nutritive value; food preparation; antinutritional factors; hydrochloric acid; denaturation; urease; enzyme inhibition; soybean meal; additives
- Abstract:
- ... Effects of chemical additives on the heat inactivation of trypsin inhibitor (TI), lipoxygenase and urease in soybeans were investigated. The nutritional value of soybeans increases when antigrowth factors, such as TI, are inactivated. Inactivation of lipoxygenase enhances palatability and storage stability. Heat inactivation of antinutritional factors during immersion cooking of dry soymeats was s ...
- Handle:
- 10113/31276
- DOI:
- 10.1007/BF02640466
- PubMed:
- 4736350
- https://doi.org/10.1007/BF02640466
- Author:
- M. A. Tabatabai
- Source:
- Soil Science Society of America journal 1973 v.37 no.5 pp. 707-710
- ISSN:
- 0361-5995
- Subject:
- clay; clay fraction; enzymatic reactions; enzyme activity; enzyme kinetics; pH; sand; silt; soil enzymes; statistical analysis; total nitrogen; urease; Iowa
- Abstract:
- ... Studies to determine the Michaelis constant (Kₘ value) for urease activity in Iowa surface soils showed that the value obtained for the activity of this enzyme was different for different soils. When the method used to determine Kₘ did not involve shaking of the soil-substrate mixtures, the Kₘ value for urease activity ranged from 1.3 × 10⁻³M to 7.0 × 10⁻³M. Shaking the soil-substrate mixtures dur ...
- DOI:
- 10.2136/sssaj1973.03615995003700050024x
- https://doi.org/10.2136/sssaj1973.03615995003700050024x
- Author:
- Sunil K. Pancholy; Elroy L. Rice
- Source:
- Soil Science Society of America journal 1973 v.37 no.1 pp. 47-50
- ISSN:
- 0361-5995
- Subject:
- amylases; beta-fructofuranosidase; endo-1,4-beta-glucanase; enzyme activity; forests; organic matter; soil enzymes; soil pH; tallgrass prairies; urease
- Abstract:
- ... Amylase, cellulase, invertase, dehydrogenase, and urease activities in soil were determined every other month for a year in two old-field successional stages and a climax stand in each of three vegetation types; tall grass prairie, post oak-blackjack oak forest and oak-pine forest. The activities of amylase, cellulase, and invertase were highest generally in the first successional stage, intermedi ...
- DOI:
- 10.2136/sssaj1973.03615995003700010018x
- https://doi.org/10.2136/sssaj1973.03615995003700010018x
- Author:
- Fred A. Norstadt; C. R. Frey; Harold Sigg
- Source:
- Soil Science Society of America journal 1973 v.37 no.6 pp. 880-885
- ISSN:
- 0361-5995
- Subject:
- Marasmius; ammonium; ammonium nitrogen; carbon dioxide; distillation; enzyme activity; fungi; humus; hydrolysis; lawns and turf; nitrate nitrogen; radioactivity; soil enzymes; soil pH; urea; urease
- Abstract:
- ... Turf infection by Marasmius oreades (Bolt.) Fr. produced concentric rings of affected soil or fairy ring phenomena. Urease activity of soil invaded by the fungus ranged from 0.86 to 15.4 mg NH₄⁺-N/100 g per 3 hours, or about 10 to 40% that in unaffected soil. Normal soil from outside the fairy rings had activity ranging from 8.9 to 36.2 mg NH₄⁺-N/100 g per 3 hours. Urease activity of soil was dete ...
- DOI:
- 10.2136/sssaj1973.03615995003700060026x
- https://doi.org/10.2136/sssaj1973.03615995003700060026x
- Author:
- M. Prasad
- Source:
- Soil Science Society of America journal 1976 v.40 no.1 pp. 130-134
- ISSN:
- 0361-5995
- Subject:
- ammonia; ammonium nitrogen; ammonium sulfate; calcareous soils; enzyme activity; fertilizer rates; pH; soil analysis; soil water; sulfur-coated urea; temperature; urea; urease; volatilization; water content; water holding capacity
- Abstract:
- ... Laboratory incubation experiments were conducted to study the comparative volatilization loss of NH₃ in a calcareous soil from sulfur-coated urea (SCU) with fast (F), medium (M), and slow (S) dissolution rates, ammonium sulfate (AS) and urea, at two temperatures 22 and 32C, and at three soil moisture levels 25, 50, and 80% of the water-holding capacity of the soil. The effect of the addition of or ...
- DOI:
- 10.2136/sssaj1976.03615995004000010035x
- https://doi.org/10.2136/sssaj1976.03615995004000010035x
- Author:
- Brian P. Spalding; J. M. Duxbury
- Source:
- Soil Science Society of America journal 1977 v.41 no.6 pp. 1109-1113
- ISSN:
- 0361-5995
- Subject:
- Lycopodium; absorbance; alpha-galactosidase; autoclaving; beta-fructofuranosidase; beta-glucosidase; calcium chloride; chitinase; endo-1,4-beta-glucanase; enzyme activity; humic acids; inulinase; lipids; nitrogen; peroxidase; phenolic compounds; polygalacturonase; soil; soil organic matter; urease; xylanases
- Abstract:
- ... The interaction of fairy rings of Lycopodium tristachyum Pursh. with the soil which they invade was examined by measurement of various soil enzymatic activities and extractable soil organic matter. The activities of cellulase, xylanase, inulinase, α-galactosidase, invertase, peroxidase, chitinase, and polygalacturonase were enhanced in soil under the rings compared with soil just outside the rings ...
- DOI:
- 10.2136/sssaj1977.03615995004100060019x
- https://doi.org/10.2136/sssaj1977.03615995004100060019x
- Author:
- R. L. Mulvaney; J. M. Bremner
- Source:
- Soil Science Society of America journal 1977 v.41 no.5 pp. 1024-1027
- ISSN:
- 0361-5995
- Subject:
- ammonia; application rate; chlorides; hydrolysis; soil; soil microorganisms; sulfonic acids; urea; urea nitrogen; urease
- Abstract:
- ... Studies to evaluate three antimetabolites patented as inhibitors of urea hydrolysis in soils (pyridine-3-sulfonic acid, desthiobiotin, and oxythiamine chloride) showed that they had no effect on production of urease by soil microorganisms and did not retard urea hydrolysis in soils or reduce gaseous loss of urea N as ammonia, even when applied at rates far exceeding those recommended for inhibitio ...
- DOI:
- 10.2136/sssaj1977.03615995004100050046x
- https://doi.org/10.2136/sssaj1977.03615995004100050046x
- Author:
- M. I. Zantua; L. C. Dumenil; J. M. Bremner
- Source:
- Soil Science Society of America journal 1977 v.41 no.2 pp. 350-352
- ISSN:
- 0361-5995
- Subject:
- calcium carbonate; cation exchange capacity; clay; enzyme activity; organic matter; pH; regression analysis; sand; silt; soil enzymes; surface area; texture; total nitrogen; urease; Iowa
- Abstract:
- ... Surface samples of 21 diverse Iowa soils representing a wide range in pH, texture, and organic matter content were studied to determine the relationships between soil urease activity and other soil properties. Simple correlation analyses showed that urease activity was correlated very highly significantly with organic C (r = 0.72***), total N (r = 0.71***), and cation-exchange capacity (r = 0.67** ...
- DOI:
- 10.2136/sssaj1977.03615995004100020036x
- https://doi.org/10.2136/sssaj1977.03615995004100020036x
- Author:
- R. J. Raison; J. W. McGarity
- Source:
- Soil Science Society of America journal 1978 v.42 no.1 pp. 140-143
- ISSN:
- 0361-5995
- Subject:
- ammonia; ammonium nitrogen; ammonium sulfate; autoclaving; cations; enzyme activity; forests; nitrogen fertilizers; potassium nitrate; soil enzymes; soil pH; urea; urease; volatilization; wildlife
- Abstract:
- ... The influence of plant ash on the transformation of N-containing fertilizers and the volatilization of NH₃ was studied in the presence and absence of soil. In moist ash alone, urea and KNO₃ were unaffected, but 63 and 70% of N applied as (NH₄)₂SO₄ was volatilized from autoclaved and nonautoclaved ashes, respectively, over a 4-day period. Volatilization of NH₃ was greater when urea or (NH₄)₂SO₄ was ...
- DOI:
- 10.2136/sssaj1978.03615995004200010031x
- https://doi.org/10.2136/sssaj1978.03615995004200010031x
- Author:
- W. D. Gould; F. D. Cook; J. A. Bulat
- Source:
- Soil Science Society of America journal 1978 v.42 no.1 pp. 66-72
- ISSN:
- 0361-5995
- Subject:
- Canavalia ensiformis; benzoquinones; catechol; disulfides; enzyme activity; enzyme inhibition; heterocyclic compounds; hydroquinone; moieties; soil; soil enzymes; sulfhydryl groups; sulfur; thiols; urease; urease inhibitors
- Abstract:
- ... The inhibition of both jack bean urease and soil urease by several heterocyclic mercaptans was investigated. The following compounds not previously tested as urease inhibitors were found to be effective inhibitors of jack bean urease: 1,3,4-thiadiazole-2,5-dithiol; 5-mercapto-3-phenyl-1,3,4-thiadiazole-2-thione; and 5-amino-1,3,4-thiadiazole-2-thiol. The disulfides of the latter two compounds were ...
- DOI:
- 10.2136/sssaj1978.03615995004200010015x
- https://doi.org/10.2136/sssaj1978.03615995004200010015x
- Author:
- Peter Larsson; Bertil Kaijser; Sante Olling; Arnnica Sohl Akerlund
- Source:
- Acta pathologica et microbiologica Scandinavica. Section C. Immunology 1978 v.86C no.1-6 pp. 215-220
- ISSN:
- 0304-1328
- Subject:
- Proteus mirabilis; immunity; immunization; pH; protective effect; pyelonephritis; urease; virulence
- Abstract:
- ... Intraperitoneal immunization with formalin‐killed bacteria as well as previous hematogenous infection with Proteus O3H1 showed a protective effect against hematogenous pyelonephritis in rats when the homologous strain was used. Transfer of hyperimmune antisera protected against hematogenously induced infection. Neither intravesical or intraperitoneal immunization with formalin‐killed bacteria nor ...
- DOI:
- 10.1111/j.1699-0463.1978.tb02583.x
- https://doi.org/10.1111/j.1699-0463.1978.tb02583.x
- Author:
- Paolo Nannipieri; Brunello Ceccanti; Stefano Cervelli; Emilio Matarese
- Source:
- Soil Science Society of America journal 1980 v.44 no.5 pp. 1011-1016
- ISSN:
- 0361-5995
- Subject:
- casein; nitrogen; nitrogen content; organic carbon; pH; proteinases; sodium pyrophosphate; soil; urease
- Abstract:
- ... Extractions of three soils at different incubation times demonstrate that 0.14M sodium pyrophosphate at pH 7.1 extracts phosphatase, urease, casein, and benzoylarginamide hydrolyzing proteases. Extraction yields of phosphatase and casein-hydrolyzing proteases are remarkably high. The most efficient length of extraction depends both on the type of soil and on the selected enzyme. Correlation analys ...
- DOI:
- 10.2136/sssaj1980.03615995004400050028x
- https://doi.org/10.2136/sssaj1980.03615995004400050028x
- Author:
- J. Ashworth; Helen M. Akerboom; J. M. Crépin
- Source:
- Soil Science Society of America journal 1980 v.44 no.6 pp. 1247-1249
- ISSN:
- 0361-5995
- Subject:
- alcohols; ammonium sulfate; carbon disulfide; enzyme activity; enzyme inhibition; enzyme inhibitors; hydrolysis; molecular weight; nitrates; nitrification; potassium; soil; soil amendments; urea; urease
- Abstract:
- ... Inhibition of urease activity and of nitrification by potassium xanthates was measured by adding them to soil amended with urea or (NH₄)₂SO₄ and determining the urea remaining or nitrate produced after incubation at 23°C. The xanthates of unsubstituted alcohols of low molecular weight were the best inhibitors of urease and nitrification. The effectiveness of nitrification inhibition was not well c ...
- DOI:
- 10.2136/sssaj1980.03615995004400060023x
- https://doi.org/10.2136/sssaj1980.03615995004400060023x
- Author:
- W. T. Frankenberger; M. A. Tabatabai
- Source:
- Soil Science Society of America journal 1981 v.45 no.2 pp. 333-338
- ISSN:
- 0361-5995
- Subject:
- air drying; amidase; clay; enzyme activity; freezing; heat; sand; soil enzymes; soil microorganisms; soil pH; soil profiles; soil sampling; statistical analysis; temperature; toluene; urease
- Abstract:
- ... Activities of soil enzymes are affected by methods of handling, storing, and pretreating the sample before enzyme assay. Amidase was recently detected in soils, and this study was carried out to assess the factors affecting its stability and distribution. Results showed that storage of field-moist samples at 5°C for 3 months decreased the activity in five soils by an average of 4%. Air-drying fiel ...
- DOI:
- 10.2136/sssaj1981.03615995004500020021x
- https://doi.org/10.2136/sssaj1981.03615995004500020021x
- Author:
- Mustakas, G.C.; Moulton, K.J.; Baker, E.C.; Kwolek, W.F.
- Source:
- Journal of the American Oil Chemists' Society 1981 v.58 no.3 pp. 300-305
- ISSN:
- 0003-021X
- Subject:
- lysine; Glycine max; simulation models; soy protein; toasting; trypsin inhibitors; soybeans; nutritive value; feed processing; water content; solvents; steaming; hexane; genetic variation; urease; soybean meal; enzyme activity
- Abstract:
- ... Even though it is well established that both underheated and overheated meals are of inferior nutritive value, comparatively little is known of the fundamental nature of the changes brought about in the protein and how these correlate with the processing conditions during toasting. In the present study we examined the interrelation of several factors in the commercial desolventizing-toasting proce ...
- Handle:
- 10113/26686
- DOI:
- 10.1007/BF02582363
- https://doi.org/10.1007/BF02582363
- Author:
- Stefano Cervelli; Carlo Ciardi; Amalia Perna
- Source:
- Journal of environmental quality 1982 v.11 no.1 pp. 82-86
- ISSN:
- 0047-2425
- Subject:
- Zea mays; ammonium nitrogen; atrazine; corn; enzyme activity; nitrogen; nitrogen balance; nitrogen cycle; soil; soil enzymes; spectroscopy; urea; urease
- Abstract:
- ... The influence of different rates of atrazine (2-chloro-4-[ethylamino]-6-[isopropylamino]-s-triazine) (0,2, and 6 kg ha⁻¹) on nitrogen balance and soil urease following ¹⁵N-urea fertilization (200 kg ha⁻¹) was investigated in corn (Zea mays L.) plots by emission spectrometry. Urease activity was affected by both urea and atrazine applications. Concentrations of NH₄⁺-N and NO₃₋-N in soil were greate ...
- DOI:
- 10.2134/jeq1982.00472425001100010020x
- https://doi.org/10.2134/jeq1982.00472425001100010020x
- Author:
- H. F. Stroo; E. M. Jencks
- Source:
- Soil Science Society of America journal 1982 v.46 no.3 pp. 548-553
- ISSN:
- 0361-5995
- Subject:
- Robinia pseudoacacia; amylases; carbon; cell respiration; clay fraction; ecosystems; enzyme activity; enzyme inhibition; fertilizers; microbial activity; mined soils; mineralization; nitrogen; organic matter; soil enzymes; soil formation; urease; vegetation
- Abstract:
- ... Microbial respiration and soil enzyme activity measurements were made in both native soils and in minesoils varying in age and vegetation in order to determine the levels of microbial activity during the initial stages of soil genesis. By all indices, microbial activity was lower on unfertilized minesoils than in native soils. Amylase and phosphatase activities increased with time, as did respirat ...
- DOI:
- 10.2136/sssaj1982.03615995004600030021x
- https://doi.org/10.2136/sssaj1982.03615995004600030021x
- Author:
- W. T. Frankenberger; F. T. Bingham
- Source:
- Soil Science Society of America journal 1982 v.46 no.6 pp. 1173-1177
- ISSN:
- 0361-5995
- Subject:
- acid phosphatase; active sites; alkaline phosphatase; alpha-galactosidase; alpha-glucosidase; amidase; arylsulfatase; calcium chloride; catalase; crop yield; crops; electrical conductivity; enzyme activity; inorganic pyrophosphatase; intracellular enzymes; microbial growth; proteinases; saline soils; salinity; sodium chloride; sodium sulfate; soil enzymes; soil sampling; thiosulfate sulfurtransferase; urease
- Abstract:
- ... Efforts were made to assess the levels of soil enzyme activities that have a specific role in the N, C, P, and S cycles of saline soils. Fieldmoist soil samples were treated with four rates of CaCl₂, NaCl, and Na₂SO₄ solutions applied to produce electrical conductivity readings of saturation extracts (ECₑ) ranging up to 22 mmho/cm. The range of ECₑ values included threshold salinity levels associa ...
- DOI:
- 10.2136/sssaj1982.03615995004600060011x
- https://doi.org/10.2136/sssaj1982.03615995004600060011x
- Author:
- K. Killham; M. K. Firestone; J. G. Mc Coll
- Source:
- Journal of environmental quality 1983 v.12 no.1 pp. 133-137
- ISSN:
- 0047-2425
- Subject:
- Pinus ponderosa; acid deposition; arylsulfatase; enzyme activity; forest soils; microbial activity; pH; rainfall simulation; seedlings; soil microorganisms; urease; California
- Abstract:
- ... In this investigation, our aim was to determine if acid rain affects soil microbial activity and to identify possible mechanisms of observed effects. A Sierran forest soil (pit 6.4) planted with Ponderosa pine seedlings was exposed to simulated rain (pH 2.0, 3.0, 4.0, and 5.6) with ionic composition reflecting that found in northern California, corresponding to 15 cm of precipitation over a 12-wee ...
- DOI:
- 10.2134/jeq1983.00472425001200010024x
- https://doi.org/10.2134/jeq1983.00472425001200010024x
- Author:
- J. M. Dunleavy
- Source:
- Crop science 1983 v.23 no.3 pp. 473-476
- ISSN:
- 0011-183X
- Subject:
- Curtobacterium flaccumfaciens; Glycine max; Phaseolus vulgaris; bacteria; beans; cultivars; disease resistance; esculin; foliar diseases; hydrolysis; leaf spot; leaves; pods; soybeans; stems; urease; wilting; wind speed; Iowa
- Abstract:
- ... A new soybean [Glycine max (L.) Merr.] disease that causes large tan necrotic spots on soybean leaves was first observed in Iowa in 1975. Necrotic areas usually fell to the ground during high winds, giving a ragged appearance to leaves. The disease was confined to leaves and was never observed on stems or pods; wilting did not occur. The causal bacterium was gram positive, motile, formed a medium- ...
- DOI:
- 10.2135/cropsci1983.0011183X002300030008x
- https://doi.org/10.2135/cropsci1983.0011183X002300030008x
- Author:
- W. T. Frankenberger; A. L. Page
- Source:
- Journal of environmental quality 1983 v.12 no.4 pp. 459-462
- ISSN:
- 0047-2425
- Subject:
- acidity; alkalinity; amidase; asparaginase; buffer index; buffers; deionization; enzymatic hydrolysis; enzyme activity; freshwater; freshwater lakes; glutaminase; ionization; pH; urease
- Abstract:
- ... The influence of acidity and alkalinity on the enzymatic hydrolysis of amide-N in the aquatic system was investigated by determining the stability of L-asparaginase (EC [Enzyme Commission] 3.5.1.1). L-glutaminase (EC 3.5.1.2), and amidase (EC 3.5.1.4), and urease (EC 3.5.1.5) with respect to pH in three freshwater lakes. The water samples were first incubated at the indicated buffer pH (1–13) for ...
- DOI:
- 10.2134/jeq1983.00472425001200040004x
- https://doi.org/10.2134/jeq1983.00472425001200040004x
- Author:
- W. T. Frankenberger; W. A. Dick
- Source:
- Soil Science Society of America journal 1983 v.47 no.5 pp. 945-951
- ISSN:
- 0361-5995
- Subject:
- acid phosphatase; alkaline phosphatase; alpha-galactosidase; alpha-glucosidase; amidase; arylsulfatase; beta-fructofuranosidase; carbon dioxide; carbon dioxide production; catalase; cation exchange capacity; chloroform; culture media; enzyme activity; extracellular enzymes; fumigation; glucose; microbial biomass; microbial growth; organomineral complexes; plate count; sand; soil enzymes; total nitrogen; urease
- Abstract:
- ... Soil enzyme activities are often used as indices of microbial growth and activity in soils. Quantitative information concerning which soil enzymes most accurately reflect microbial growth and activity is lacking. Relationships between the activities of 11 soil enzymes and microbial respiration, biomass, viable plate counts, and soil properties were determined in surface samples of 10 diverse soils ...
- DOI:
- 10.2136/sssaj1983.03615995004700050021x
- https://doi.org/10.2136/sssaj1983.03615995004700050021x
- Author:
- W. A. Torello; D. J. Wehner
- Source:
- Agronomy journal 1983 v.75 no.4 pp. 654-656
- ISSN:
- 0002-1962
- Subject:
- Argiudolls; Poa pratensis; air drying; ammonia; culture media; ecosystems; enzyme activity; fertilizer application; greenhouses; hydrolysis; lawns and turf; plant growth; plant tissues; seasonal variation; silt loam soils; soil enzymes; soil sampling; temperature; thatch; topical application; turf grasses; urea; urea fertilizers; urea nitrogen; urease; volatilization
- Abstract:
- ... The components of a turfgrass ecosystem, including plants, an intervening layer of thatch and the underlying soil, influence the fate of topically applied urea fertilizer. The loss of urea N by ammonia volatilization may be governed by the rate of urea hydrolysis. The main objective of this study was to determine the extent of urease activity associated with turfgrass plant tissue, thatch, and the ...
- DOI:
- 10.2134/agronj1983.00021962007500040018x
- https://doi.org/10.2134/agronj1983.00021962007500040018x
- Author:
- Gosewinkel, U.; Broadbent, F.E.
- Source:
- Communications in soil science and plant analysis 1984 v.15 no.11 pp. 1377-1389
- ISSN:
- 0010-3624
- Subject:
- urease; soil enzymes; soil analysis
- DOI:
- 10.1080/00103628409367564
- https://doi.org/10.1080/00103628409367564
- Author:
- W. A. Dick
- Source:
- Soil Science Society of America journal 1984 v.48 no.3 pp. 569-574
- ISSN:
- 0361-5995
- Subject:
- Avena sativa; Fragiudalfs; Glycine max; Medicago sativa; Zea mays; acid phosphatase; alkaline phosphatase; amidase; arylsulfatase; beta-fructofuranosidase; conventional tillage; corn; crop rotation; enzyme activity; no-tillage; pH; regression analysis; silt loam soils; silty clay loam soils; soil enzymes; soil profiles; urease
- Abstract:
- ... The effects of long-term no-tillage practices on the activity of enzymes in soil are not well understood. Soil profile (0–30 cm) samples were collected from plots where various tillage and rotation combinations had been continuously applied to a Hoytville silty clay loam (Mollic Ochraqualfs) soil (18 yr) and a Wooster silt loam (Typic Fragiudalfs) soil (19 yr). With the exception of alkaline phosp ...
- DOI:
- 10.2136/sssaj1984.03615995004800030020x
- https://doi.org/10.2136/sssaj1984.03615995004800030020x
- Author:
- Blanco, M.J.; Suarez, C.; Vicente, C.
- Source:
- Planta 1984 v.162 no.4 pp. 305-310
- ISSN:
- 0032-0935
- Subject:
- lichens; urea; phenolic compounds; urease
- DOI:
- 10.1007/BF00396741
- PubMed:
- 24253163
- https://doi.org/10.1007/BF00396741
- Author:
- O'Toole, P.; Morgan, M.A.; McGarry, S.J.
- Source:
- Communications in soil science and plant analysis 1985 v.16 no.7 pp. 759-773
- ISSN:
- 0010-3624
- Subject:
- pastures; tillage; regression analysis; soil enzymes; arable soils; urease; grassland soils; Ireland
- DOI:
- 10.1080/00103628509367642
- https://doi.org/10.1080/00103628509367642
- Author:
- D. Panda; S. Patnaik
- Source:
- Journal of the Indian Society of Soil Science 1985 v.33 no.4 pp. 811-815
- ISSN:
- 0974-0228
- Subject:
- Cajanus cajan; hydrolysis; pigeon peas; soil; steam distillation; urea; urea nitrogen; urease
- Abstract:
- ... A freshly prepared 5% water extract of commercial ground split pigeon pea, (Cajanus cajan) served as a good source of urease and 5 ml of the extract completely hydrolyzed urea in two hours. NH₄-N and urea-N in a mixture of the solution can be determined separately by steam distillation with MgO suspension in a Pregl-Parnas Wagner steam distillation apparatus, before and after hydrolysis with pigeo ...
- Author:
- Dalal, R.C.
- Source:
- Soil research 1985 v.23 no.1 pp. 49-60
- ISSN:
- 0004-9573
- Subject:
- soil enzymes; urease; soil salinity; kinetics; thermodynamics
- DOI:
- 10.1071/SR9850049
- https://doi.org/10.1071/SR9850049
46. Effect fo assay conditions and field exposure on urease activity associated with cereal residues
- Author:
- Goos, R.J.
- Source:
- Communications in soil science and plant analysis 1985 v.16 no.4 pp. 399-409
- ISSN:
- 0010-3624
- Subject:
- Triticum aestivum; Secale cereale; urea fertilizers; crop residues; urease; soil properties; soil fertility; soil biology; North Dakota
- DOI:
- 10.1080/00103628509367614
- https://doi.org/10.1080/00103628509367614
- Author:
- G. Bitton; B. G. Volk; D. A. Graetz; J. M. Bossart; R. A. Boylan; G. E. Byers
- Source:
- Journal of environmental quality 1985 v.14 no.1 pp. 69-71
- ISSN:
- 0047-2425
- Subject:
- acid deposition; acidity; enzyme activity; lakes; microbial activity; nitrification; pH; soil; soil respiration; urease
- Abstract:
- ... The effects of acid precipitation on selected microbiological processes were investigated under field conditions. The study site, near Lake McCloud, FL, was composed of three transects, each including three plots. Each transect was spray-irrigated with lake water at various levels of acidity. Acid rain did not significantly reduce dehydrogenase, phosphatase, or urease activity; protease activity w ...
- DOI:
- 10.2134/jeq1985.00472425001400010013x
- https://doi.org/10.2134/jeq1985.00472425001400010013x
- Author:
- R. J. B. Bouwmeester; P. L. G. Vlek; J. M. Stumpe
- Source:
- Soil Science Society of America journal 1985 v.49 no.2 pp. 376-381
- ISSN:
- 0361-5995
- Subject:
- Calciustolls; air; ammonia; application methods; drying; environmental factors; enzyme activity; fertilizer application; greenhouse experimentation; greenhouses; hydrolysis; leaching; nitrogen; rain; semiarid zones; soil water; stable isotopes; topsoil; urea; urea nitrogen; urease; volatilization; wilting point; wind speed; wind tunnels
- Abstract:
- ... A greenhouse experiment using ¹⁵N followed by wind tunnel experiments using a micrometeorological technique were conducted to identify some of the factors that contribute most significantly to ammonia (NH₃) volatilization in a simulated semiarid environment following application of urea. An Aridic Calciustolls with high urease activity was subjected to a variety of initial soil moisture contents, ...
- DOI:
- 10.2136/sssaj1985.03615995004900020021x
- https://doi.org/10.2136/sssaj1985.03615995004900020021x
- Author:
- H. F. Stroo; E. M. Jencks
- Source:
- Journal of environmental quality 1985 v.14 no.3 pp. 301-304
- ISSN:
- 0047-2425
- Subject:
- Festuca arundinacea; amylases; enzyme activity; fertilizer application; fertilizers; microbial activity; mined soils; sandy loam soils; sewage sludge; urease
- Abstract:
- ... The effect of lime, fertilizer, and sewage sludge (50 and 100 kg ha⁻¹) upon microbial activity and growth of sparsely distributed tall fescue (Festuca arundinaceae Schreb.) on an old, acidic, infertile sandy loam (Typic Udispolents; loamy-skeletal, mixed, acid, mesic) minesoil was evaluated. Respiration rate and activities of amylase, urease, and phosphatase were used as indices of microbial activ ...
- DOI:
- 10.2134/jeq1985.00472425001400030001x
- https://doi.org/10.2134/jeq1985.00472425001400030001x
- Author:
- C. M. Reynolds; D. C. Wolf; J. A. Armbruster
- Source:
- Soil Science Society of America journal 1985 v.49 no.1 pp. 104-108
- ISSN:
- 0361-5995
- Subject:
- air drying; ammonia; carbon dioxide; crop production; fields; hydrolysis; nitrogen; organic carbon; pastures; soil; total nitrogen; urea; urease; Kansas; Missouri; Oklahoma
- Abstract:
- ... The use of urea as a nitrogen source for crop production has increased in recent years. Because the hydrolysis of urea to ammonia and carbon dioxide is mediated by the enzyme urease, efficient use of urea requires an understanding of factors that influence urea hydrolysis in soil. The purpose of this research was to relate the rate of urea hydrolysis to chemical, physical, and biological propertie ...
- DOI:
- 10.2136/sssaj1985.03615995004900010021x
- https://doi.org/10.2136/sssaj1985.03615995004900010021x