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1

Evaluation of urease activity by the human Ureaplasma species

100%

Biernat-Sudolska M. , Bilska-Wilkosz A. , Rojek-Zakrzewska D. , Zawilinska B. , Kosz-Vnenchak M.

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nr 3

2

Impact of afforestation on the limitation of the spread of the pollutions in ground water and in soils

100%

Szajdak L. , Zyczynska-Baloniak I. , Jaskolska R.

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tom 12

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nr 4

EN

The investigations were carried out from 1997 to 2001. It was shown the function of the leafy shelter-belt as biogeochemical barrier of total length 114 m by changes of different forms of nitrogen in soil (total, nitrate, ammonium and organic) and in the ground water under shelterbelt and also activity of urease in soil. This shelterbelt is located on two kinds of soil. It was found the impact of the edge of the shelterbelt on the changes of different forms of nitrogen in soil and in ground water and also activity of urease in soils. It was observed that the significant impact on the decrease of nitrogen in ground water and in soils exerts the distance from the edge of shelterbelt. The highest decrease of analyzed compounds was observed in the first sector of shelterbelt (16.5 m). Additionally the effect of eluted cations Ca+2 and Mg+2 on the compensation of pH value of the ground water was also observed.

3

Evaluation of the effect of carbamylphosphate synthetase and urease activities in selected strains of wine yeast on the production of ethyl carbamate

100%

Balcerek M. , Szopa J. S.

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nr 4

EN

The study was aimed at evaluating the enzymatic capacity of selected strains of wine yeast S. cerevisiae for the production of carbamylphosphate synthetase (EC 6.3.4.16) and urease (EC 3.5.1.5) as well as their effect on the production of ethyl carbamate in plum mashes. The experimental material were strains of wine yeast: Syrena, Tokay, Burgund, Bordeaux, Steinberg, originating from the Pure Cultures Collection of the Institute of Fermentation Technology and Microbiology, Technical University of Łódź, and Saccharomyces bayanus yeast by Prochimica Varese SRL company (Italy). Distillery fruit mashes were prepared from plums var. Węgierka łowicka. Under conditions of alcoholic fermentation, the highest activities of NH4+-dependent carbamylphosphate synthetase (45.43 x 10-3 U/mg protein) and urease (0.57 U/mg protein) were observed for the strain Steinberg. Irrespective of the activity (3.2–92.95 U/mg protein) of carbamylphosphate synthetase in the yeast strains examined, the concentration of ethyl carbamate in after-fermentation liquids was at a similar level (<0.01 mg/L). Under conditions of a limited access of oxygen, the maximum activity of urease in S. bayanus yeasts (1.66 U/mg protein), was observed at the stage of preliminary fermentation (yeasts in the stationary phase of growth). Culture media of the Steinberg strain were found to demonstrate a relatively high degree of urea reduction under anaerobic conditions – 19% and a trace concentration of urethane (<0.01 mg/L). A low urolytic activity (0.192 U/mg protein) of yeasts of the Tokay strain was reflected in a relatively high concentration of urethane (0.210 mg/L of 40% spirit) in plum spirit obtained with their participation. Fermentation of plum mash with S. bayanus yeast applied at a dose of 0.5 g d.m./kg, resulted in a decrease in the concentration of ethyl carbamate by 44% (0.07 mg/L of 40% spirit), as compared to the dose of 0.1-0.3 g d.m./kg.

PL

Celem pracy była ocena uzdolnień enzymatycznych wybranych ras drożdży winiarskich S. cerevisiae do tworzenia syntetazy karbamylofosforanu (EC 6.3.4.16 ) i ureazy (EC 3.5.1.5) oraz ich wpływu na powstawanie karbaminianu etylu w zacierach śliwkowych. Materiał do badań stanowiły szczepy drożdży winiarskich: Syrena, Tokay, Burgund, Bordeaux, Steinberg, pochodzące z Kolekcji Czystych Kultur Instytutu Technologii Fermentacji i Mikrobiologii PŁ oraz drożdże Saccharomyces bayanus firmy Prochimica Varese SRL (Włochy). Do sporządzenia gorzelniczych zacierów owocowych wykorzystywano śliwki odmiany Węgierka łowicka. W toku przeprowadzonych eksperymentów wykazano, że najwyższą aktywnością syntetazy karbamylofosforanu NH4 +- zależnej (45.43 × 10-3 U/mg białka) i ureazy (0.57 U/mg białka), w warunkach fermentacji alkoholowej, odznaczał się szczep Steinberg. Niezależnie od aktywności (3.2–92.95 U/mg białka) syntetaz karbamylofosforanu w badanych szczepach drożdży, stężenie karbaminianu etylu w cieczach pofermentacyjnych było na zbliżonym poziomie (<0.01 mg/L). W warunkach ograniczonego dostępu tlenu, maksymalna aktywność ureazy w drożdżach S. bayanus (1.66 U/mg białka), przypadała na etap zafermentowania (drożdże w fazie stacjonarnej). W podłożach, w których hodowano szczep Steinberg, odnotowano stosunkowo wysoki stopień redukcji mocznika w warunkach beztlenowych – 19% oraz śladowe stężenie uretanu (<0.01 mg/L). Niska aktywność ureolityczna (0.192 U/mg białka) drożdży rasy Tokay, znalazła odzwierciedlenie w relatywnie dużym stężeniu uretanu (0.210 mg/L spirytusu 40%) w spirytusie śliwkowym, otrzymanym z ich udziałem. Fermentacja zacieru śliwkowego drożdżami S. bayanus, w ilości 0.5 g s. s. /kg, wpłynęła na obniżenie zawartości karbaminianu etylu o 44% (0.07 mg/L spirytusu 40%) w stosunku do dawki 0.1–0.3 g s. s./kg.

4

Eco-chemical forest soil indices from a forest fire

80%

Bielinska E. J. , Mocek-Plociniak A. , Kaczmarek Z.

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nr 5

665-671

EN

Our paper presents results of investigations aimed at determining correlations between the content of polycyclic aromatic hydrocarbons (PAHs) and the enzymatic activity of a forest soil on an extensive area of forest damaged by a large fire 12 years ago. The investigations comprised experimental plots in the cultivations of Scots pine (Pinus sylvestris L.) and grey alder (Alnus incana L.) MOENCH on three sample surfaces on which different methods of soil preparation were applied. The statistical analysis of the obtained results clearly showed the inhibiting influence of the PAH content on the activity of dehydrogenases, acid phosphatase, alkaline phosphatase and protease, which indicated that the examined soils were loaded with PAHs to such a degree that it was dangerous to living organisms. A highly significant positive correlation was found between urease activity and PAH content.

5

Urease activity in soil contaminated with polycyclic aromatic hydrocarbons

80%

Lipinska A. , Kucharski J. , Wyszkowska J.

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tom 22

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nr 5

EN

Urease activity was determined in soil contaminated with four polycyclic aromatic hydrocarbons (PAHs): naphthalene, phenanthrene, anthracene, and pyrene in the amount of 0, 1,000, 2,000, and 4,000 mg·kg⁻¹ DM soil. Organic materials – cellulose, sucrose, and compost – were applied to the samples in the amount of 0 and 9 g·kg⁻¹ DM soil. The experiment was carried out in a laboratory, and soil samples consisted of loamy sand. Soil resistance (RS) and soil resilience (RL) were determined. Soil contamination with PAHs had an adverse effect on urease activity, and naphthalene had the most inhibitory impact on the studied enzyme. Urease activity was significantly determined by the dose of PAH, soil incubation time, and the type of organic material. Soil resistance to PAHs decreased with an increase in contamination levels. The addition of sucrose, cellulose, and compost increased soil's resistance to the toxic effects of naphthalene and phenanthrene. Soil resilience values indicate that polycyclic aromatic hydrocarbons cause long-term impairment of urease activity.

6

Microbial activity in soil inoculated with different mutants of Pseudomonas fluorescens

80%

Kozdroj J.

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nr 1

7

Wplyw temperatury na parametry kinetyczne Michaelisa-Mentena ureazy glebowej

70%

Samborska A. , Stepniewska Z.

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tom 38

165-174

PL

Celem badań było zbadanie wpływu różnego zakresu temperatur na parametry kinetyczne Michaelisa-Mentena ureazy glebowej. Badaniom poddano próby zawierające czysty enzym (E), glebę nie nawadnianą ściekami wzbogacona enzymem (E + G) i glebę wielokrotnie nawadniana ściekami (G). Aktywność ureazową przy różnych stężeniach mocznika 0,01-3% i w różnych temperaturach: 0, 20, 37, 60°C oznaczano metodą Bonmanti i współ [I], Stałą Michaelisa (Km) i szybkość maksymalną (Vmax) wyznaczono metodą Liweavera-Burka. Aktywność ureazowa (AU) najniższa była w temperaturze 0°C, i wynosiła: 0,02 (µN-NH4 kg-1 h-1 w próbie z enzymem, 0,013 µN-NH4 kg-1 h-1 w kombinacji enzym + gleba, 0,05 (µN-NH4 kg -1h-1 w glebie irygowanej ściekami. Wraz ze wzrostem temperatury obserwowano wzrost aktywności enzymu. W temperaturze 20°C AU przedstawiała się następująco dla: E = 0,10 µN-NH4 kg-1 h-1 E + G = 0,08µN-NH4 kg-1 h -1G = 0,03 µN-NH4 kg-1 h-l. Najwyższe wartości aktywności ureazowej zanotowano w temperaturze 37°C : 0,35 µN-NH4, kg-1 h-1 dla próby zawierającej preparat handlowy, 0,16 µN-NH4 kg-1 h-l w kombinacji gleba wzbogacona enzymem, 0,125 µN-NH4 kg-1 h-1 dla gleby irygowanej ściekami miejskimi Wzrost temperatury do 60°C powodował spadek aktywności enzymatycznej. W zakresie temperatur 0-37°C zanotowano spadek wartości stałej Michaelisa i wzrost szybkości maksymalnej zachodzącej reakcji we wszystkich analizowanych wariantach, natomiast w 60°C twierdzono wzrost Km i spadek wartości Vmax. W oparciu o analizę otrzymanych wyników można stwierdzić że ureaza wykazuje największe powinowactwo względem substratu w temperaturze 37°C, natomiast wzrost temperatury jak również jej spadek zmniejsza dostępność mocznika dla enzymu.

EN

The aim of the investigations was to measure relationship between temperature and Michaelis-Menten's kinetic parameters of soil's urease. The measurements were performed on three kinds of samples: the first one containing pure enzyme (E), the second one containing soil never irrigated with waste water but amended with pure enzyme (R + G), the third one containing soil irrigated with waste water after II step purification (G). Urease activity at di fferent concentration of urea 0,01-3% and temperature: 0, 20, 37, 60 ° C was marked with the help of Bounmanti et al. [1] method. Michaelis Constant (Km) and maximum potential activity (Vmax) were determined by method of Liwcaver-Burk. The lowest urease activity (AU) was found at 0°C and was determined for different samples: 0,02 µN-NH4 kg-1 h-1 for the sample with pure enzyme, 0,01.3 µN-NH4 kg-1 h-1 soil never irrigated with waste water but enhanced with pure enzyme, 0,05 µN-NH4 kg-1 h-1 soil irrigated with waste water after II step purification. With an increase of temperature the urease activity level was observed. At 20°C the following value of AU was found in samples: 0,10 µN-NH4 kg-1 h-1 for E, 0,08 µN-NH4 kg-1 h-1 for E + G, 0,03 µN-NH4 kg -1 h-1 for G. The highest urease activity was observed at the temperature of 37°C and it was 0,33 µN-NH4 kg-1 h-1 for E, 0,16 µN-NH4 kg-1 h-1 for E + G, 0,125 µN-NH4 kg-1 h-1 for G, The rise of temperature to the level of 60°C caused a decrease of urease activity. With an increase of temperature within the range of 0-37°C a decrease of Michaelis constants was noticed and increase of maximum potential activity in all the analysed samples. At 60°C decrease Km and Vax was observed. On the basis of results obtained it is possible to conclude that urease shows the highest activity at 37°C, whilst an increase of temperature or its decrease reduce the activity.