Wyniki wyszukiwania - Biblioteka Nauki

1

Method of measurement of nitrate reductase activity in field conditions

100%

Krywult M. , Bielec D.

Journal of Ecological Engineering

|

2013

|

tom Vol. 14, nr 1

7--11

EN

For the last three decades the interest in biomonitoring and ecological studies has been rapidly growing. Therefore, it was necessary develop of new methods of analysis for biochemical parameters which allow to quantify biological response of investigated organisms for environmental factors. The main goal of this paper demonstrates optimal conditions for enzyme kinetics analysis conducted in the field in situ. Nitrate reductase activity is typically assayed in vivo by measuring nitrite production in tissue which has been vacuum infiltrated with buffered nitrate solution. For this study a nitrate reductase assay was adapted from a number of studies with own modifications of authors. Leaves of examined plants were collected from the investigated plots and immediately placed into test tubes with buffer solution (potassium phosphate dibasic containing 0.6% propanol-1) and evacuated in 0.33 atm. for 10 minutes. Then, known amount of potassium nitrate was added, and the solution sample was analyzed in order to obtain a background level of nitrite. The foliage samples were incubated for 2 hours at 20 °C in darkness. Following this procedure, they were given the most optimal conditions for reaction stability. After incubation the amount of synthesized nitrite was determined colorimetrically using sulfanilamide and N-(1-naphthyl)ethylenediamine dihydrochloride, measured at 540 nm. The foliage samples were oven-dried to obtain dry mass. The level of nitrate reductase activity was calculated as the amount of nitrite produced in nmol per gram of dry mass of foliage tissue per hour. The result obtained during the research demonstrate the changes of nitrate reductase dynamics according to change of incubation parameters. Dynamics of enzyme activity with changes of solution pH and incubation temperature was presented. Installation for conducting infiltration process and construction of incubation chamber is also described in this paper.

2

Nitrate reductase activity in fragments of main shoot of rye [Secale cereale L.]

100%

Wojcieska U. , Wolska E. , Giza A.

Acta Physiologiae Plantarum

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1992

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tom 14

|

nr 2

3

The activity of nitrate reductase in organs of pea plants

88%

Wojcieska U. , Wolska E. , Podlesna A. , Kocon A.

Bulletin of the Polish Academy of Sciences. Biological Sciences

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1994

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tom 42

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nr 2

4

Nitrate reductase in [NR] mutants of Solanum tuberosum L. I. Preliminary biochemical characterization

88%

Chwilkowska B. , Polcyn W. , Ratajczak L. , Brzozowicz M.

Acta Physiologiae Plantarum

|

1995

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tom 17

|

nr 1

5

The impact of production of silver nanoparticles using soil fungi and its applications for reducing irrigation water salinity

75%

Yaseen R. , Kotp Y. H. , Eissa D.

Journal of Water and Land Development

|

2020

|

tom no. 46

216--228

EN

In the present work, the dried biomass of soil isolated fungus Eurotium cristatum was used for synthesizing silver nanoparticles (AgNPs). The synthesized AgNPs were spherical in shape with average diameter of 16.56 nm and displayed maximum absorbance at 418. Fourier transform infrared (FTIR) study indicated the presence and binding of proteins with myco-produced silver nanoparticles. The optimum conditions for AgNPs biosynthesis were found to be at temperature of 40°C, pH of 8.0, substrate concentration of 500 ppm and fungal biomass wt. of 0.8 g. The AgNPs showed antibacterial activity against Staphylococcus aureus, Listeria monocytogenes, Escherichia coli and Shigella flexneri. AgNPs was built-in thin film nanocomposite (TFNC) membrane and the impacts of nanomaterial composition on membrane properties and desalination process were studied. The AgNPs produced membrane TFNC had better filtration performances than pure thin film composite membrane TFC. The TFNC membrane had enhanced water flux (32.0 vs. 16.5 dm3∙m–2∙h–1) and advanced NaCl rejection (91.7 vs. 89%) compared to the TFC membrane. A pot experiment was conducted to evaluate the effect of the irrigation with desalinated water on yield and productivity of essential oil of the sweet basil (Ocimum basilicum L.) and lavender (Lavandula multifida L.). The irrigation with desalinated water reduced significantly the soil reaction, soil electrical conductivity (EC), sodium adsorption ratio and exchangeable sodium percent in rhizospheric soil, it also enhanced the growth and oil yield of both plants compared with those irrigated with salt water.

6

Nitrate reductase activity and protein content in leaves and roots of two doubled haploid barley lines depengis on seedling age and nitrogen source

75%

Skoczek H.

Acta Physiologiae Plantarum

|

1992

|

tom 14

|

nr 2

7

Effects of ultraviolet, monochromatic and PAR waveband on nitrate reductase activity and pigmentation in a rice field cyanobacterium, Anabaena sp.

75%

Sinha R. P. , Krywult M. , Hader D. P.

Acta Hydrobiologica

|

1998

|

tom 40

|

nr 2

8

Salinity and abscisic acid effects on the nitrate reductase activity in wheat seedlings

75%

Naqvi S. S. M. , Mumtaz S. , Shereen A. , Khan A. H. , Khan M. A. , Ashraf M. Y.

Acta Physiologiae Plantarum

|

1996

|

tom 18

|

nr 2

9

Effects of continuous light-dark and 2,5-norbornadiene on nitrate reductase activity in spinach leaves

75%

Oral B. , Tasgin E. , Demir Y. , Nalbantoglu B.

Bulletin of the Polish Academy of Sciences. Biological Sciences

|

2003

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tom 51

|

nr 1

10

Effect of Film Used in Low Tunnels and for Plant Shading on Nitrate Metabolism in Celery Stalks

63%

Wojciechowska R. , Siwek P.

Ecological Chemistry and Engineering. A

|

2011

|

tom Vol. 18, nr 1

139-145

EN

The results of three-year studies (2005-2007) on the effect of various colours of film (transparent, white, and black) made of original and recycled materials used as tunnel covers and plant shades before harvest on the nitrate metabolism in celery, 'Tango' cv., have been presented. Nitrate content, nitrate reductase activity as well as ammonium ions and free amino acid content in celery stalks were estimated. In the first experiment celery plants were grown in tunnels since the day of planting, then the films were removed a month before harvest and in the second one - film shades of proper films were fixed on the low tunnels construction two weeks before harvest. The content of nitrate and its metabolism was more significantly modified in the second experiment; with the reducing PAR permeability of film, the significant decrease of nitrate activity in celery stalks was shown. In both experiments the lowest content of nitrates was estimated in stalks of the celery grown under transparent film. The highest content of free amino acids in celery stalks in black film application was observed. The film colour had greater effect on nitrate content and its metabolism than the material of the film.

PL

Przedstawiono wyniki trzyletnich badań (2005-2007) nad wpływem folii polietylenowej wykonanej z surowca oryginalnego i recyklingowego (bezbarwnej, białej i czarnej) wykorzystanej do pokrycia tuneli niskich oraz do cieniowania roślin przed zbiorem na metabolizm azotanów w ogonkach liściowych selera naciowego odmiany 'Tango'. Wykonano oznaczenia zawartości azotanów, aktywności reduktazy azotanowej, jak również zawartości jonów amonowych oraz wolnych aminokwasów. W pierwszym doświadczeniu rośliny selera rosły w tunelach od wysadzenia rozsady, po czym około miesiąc przed zbiorem zdejmowano folie, a w drugim - folie rozciągano na konstrukcji tuneli niskich na dwa tygodnie przed zbiorem. Zawartość i przemiany azotanów były bardziej modyfikowane w doświadczeniu drugim; wraz ze zmniejszaniem się przepuszczalności folii dla PAR stwierdzono znaczny spadek aktywności reduktazy azotanowej w ogonkach liściowych selera. W obu eksperymentach najniższy poziom azotanów odnotowano w ogonkach selera, zebranych spod folii bezbarwnych. Największa, zawartość wolnych aminokwasów obserwowano w kombinacjach z folią czarną. Większy wpływ na zawartość i przemiany azotanów miało zabarwienie użytych folii niż materiał, z którego je wykonano.

11

Measurement of nitrate reductase activity in a field conditions – methodology

63%

Krywult M. , Bielec D.

Inżynieria Ekologiczna

|

2013

|

tom Nr 32

115--121

EN

During recent three decades interest for biomonitoring and ecological studies was rapidly growing. Therefore was necessary develop of new methods of analysis biochemical parameters whose allow quantify biological response of investigated organisms for environmental factors. The main goal of this paper demonstrates optimal conditions for enzyme kinetics analysis conducted in the field in situ. Nitrate reductase activity is typically assayed in vivo by measuring nitrite production in tissue which has been vacuum infiltrated with buffered nitrate solution. For this study a nitrate reductase assay was adapted from a number of studies with own modifications of authors. Leaves of examined plants were collected on investigated plots and immediately placed into test tubes with buffer solution (potassium phosphate dibasic containing 0.6% propanol-1) and evacuated in 0.33 atm. for 10 minutes. Then known amount of potassium nitrate was added, and the solution sample was analyzed in order to obtain a background level of nitrite. The foliage samples were incubated for 2 hours at 20 °C in darkness. Follow this procedure have given the most optimal conditions for reaction stability. After incubation the amount of synthesized nitrite was determined colorimetrically using sulfanilamide and N-(1-naphthyl)ethylenediamine dihydrochloride, measured at 540 nm. The foliage samples were oven-dried to obtain their dry mass. Level of nitrate reductase activity was calculated as the amount of nitrite produced in nmol per gram of dry mass of foliage tissue per hour. The result obtained during these research demonstrate the changes of nitrate reductase dynamics according to change of incubation parameters. Dynamics of enzyme activity with changes of solution pH and incubation temperature was presented. Installation for conducting infiltration process and construction of incubation chamber is also described in this paper.

PL

W ciągu ostatnich trzech dekad zainteresowanie biomonitoringiem i badaniami ekologicznymi szybko wzrastało. Dlatego zaistniała konieczność rozwoju nowych metod analiz parametrów biochemicznych, które pozwoliłyby określić biologiczna odpowiedź badanych organizmów na działanie czynników środowiskowych. Głównym celem artykułu jest przedstawienie optymalnych warunków dla analiz kinetyki reakcji enzymatycznych przeprowadzonych w warunkach terenowych. Aktywność reduktazy azotanowej jest zwykle badane in vivo poprzez pomiar produkcji azotynów w tkankach roślinnych, które zostały poddane infiltracji w buforowanym roztworze azotanów. Metodykę oparto o liczne opracowania badawcze oraz wprowadzone własne modyfikacje. Liście dębu zbierano na badanej powierzchni, natychmiast umieszczano w probówkach z roztworem buforowym (fosforan potasu z dodatkiem 0,6% propanolu-1) i poddawano działaniu podciśnienia 0,33 atm. przez 10 min. Następnie dodano znaną ilość azotanu potasu, po czym próbkę roztworu oznaczano dla określenia zerowego stężenia azotynów. Próbki liści inkubowano przez 2 godziny w 20 °C w ciemności. W ten sposób uzyskano warunki stabilności reakcji. Po zakończeniu inkubacji stężenie zsyntezowanego azotynu określono kolorymetrycznie przy użyciu sulfanidamidu oraz N-(1-naftylo)etylenodwuaminy x 2HCl przy długości fali 540 nm. Próbki liści suszono do uzyskania suchej masy. Poziom aktywności reduktazy azotanowej obliczono jako ilość zsyntezowanego azotynu [nmol] na gram suchej masy na godzinę. Uzyskane wyniki wskazują dynamikę zmian aktywności reduktazy odpowiednio do zmian warunków inkubacji. Przedstawiono dynamikę zmian aktywności enzymu w zależności od pH buforu i temperatury inkubacji. Zaprezentowano również instalację dla przeprowadzenia procesu infiltracji i inkubacji liści.

12

The impact of production of silver nanoparticles using soil fungi and its applications for reducing irrigation water salinity

63%

Yaseen R. , Kotp Y. , Eissa D. , Yaseen R. , Kotp Y. , Eissa D.

|

13

Localization of nitrogenase and nitrate reductase in the Cycas-Anabaena cycadeae association

63%

Sharma A. , Mishra P. , Kumar A.

Acta Biologica Cracoviensia. Series Botanica

|

2004

|

tom 46

213-216

EN

Induction of nitrate reductase (NR) activity in coralloid roots of Cycas revoluta was observed after 8 h incubation in 0.02 M KNO3. Other plants growing near Cycas showed a higher level of NR immediately when incubated in KNO3. In contrast to NR, intact coralloid roots showed very high nitrogenase activity (~1.2 to 1.6 µmol C2H4 g fresh wt-1 h-1) under both light and dark conditions as compared to transverse sections of roots. Localization of NR and nitrogenase was tested in coralloid roots using different sets of roots and also in the endophyte. Our results showed that NR activity was mainly due to the endophyte (Anabaena cycadeae); coralloid roots lacked it, as no NR activity was observed in chloramphenicol-treated intact root samples.

14

Purification and some physicochemical properties of nitrate reductase isolated from winter triticale seedlings

63%

Sempruch C. , Ciepiela A. P. , Sprawka I. , Chrzanowski G.

Electronic Journal of Polish Agricultural Universities. Series Biology

|

2008

|

tom 11

|

nr 1

15

Mass spectrometry identification of membrane-bound respiratory nitrate reductase from Bradyrhizobium sp. [Lupinus]

63%

Polcyn W.

Acta Biochimica Polonica

|

2008

|

tom 55

|

nr 4

753-760

EN

Respiratory nitrate reductase (NR) from Bradyrhizobium sp. (Lupinus) USDA 3045 has biochemical properties of the membrane-bound NR type. However, in the completely sequenced rhizobium genomes only genes for the periplasmic type of dissimilatory NR were found. Therefore purification and identification of the enzyme by tandem mass spectrometry (MS/MS) was under taken. MS/MS spectra representing 149 unique tryptic peptides derived from purified 137-kDa subunit matched the NCBInr-deposited NarG sequences. MS/MS sequencing of two other SDS/PAGE bands (65- and 59-kDa) identified them as derivatives of the NarH-type protein. Applying additional validation criteria, 73% of the sequence of the NarG subunit (902 aa) and 52% of NarH sequence (266 aa) was assembled (UniProt KB acc. no. P85097 and P85098). This is the first unambiguous identification of an active NarGH-like NR in rhizobia. Moreover, arguments are provided here for the existence of a functional enzyme of this type also among other rhizobial species, basing on immunoblot screening and the presence of membrane-associated NR-active electrophoretic forms.

16

Impact of shelterbelts on oxidation-reduction properties and greenhouse gases emission from soils

63%

Szajdak L. W. , Gaca W. , Augustin J. , Meysner T.

Ecological Chemistry and Engineering. S

|

2018

|

tom Vol. 25, nr 4

643--658

EN

The Typic Hapludalfs soils under two old shelterbelts (200 years old) Robinia pseudacacia and Crataegus monogyna, multi species of trees (young shelterbelt - 20 years old) and neighbouring cultivated fields were investigated. The function of shelterbelts of different age and plant composition in agricultural landscape and estimation of biochemical and chemical soil conditions for the decrease of greenhouse gases release from soil to the atmosphere was the aim of the research. In soils under shelterbelts were estimated activities of several enzymes participating in the oxidation-reduction processes, ferric and ferrous ions and the evolutions of gases like N2, N2O, CO2, and CH4. The soils under old shelterbelts characterized higher peroxidase activity than in young shelterbelt and adjoining cultivated fields. However, no significant differences were observed for nitrate reductase activity between old and young shelterbelts. There were proved differences between emission of N2O in soils under shelterbelts and in adjoining cultivated fields. Furthermore, it was observed significant effect of the young shelterbelt on the decrease of carbon dioxide release than in the adjoining cultivated field. The manipulation of the landscape through the introduction of shelterbelts of different age and the composition of plants leads to the modification of biogeochemical soil conditions for N2O and N2 formation and finally decrease of the greenhouse gases evolution from soils to the atmosphere. Thus the creation of new shelterbelts is favourable factor for agricultural landscape.

17

New insights into functional roles of nitric oxide in roots

63%

Gupta K. , Igamberdiev A. , Kruger N. , Kaiser W. , Ratcliffe G.

BioTechnologia. Journal of Biotechnology Computational Biology and Bionanotechnology

|

2013

|

tom 94

|

nr 2

18

On the role of bacterial inoculum growth conditions on nitrate denitrification pathway

63%

Blaszczyk M. , Jastrzebska E. , Mycielski R.

Acta Microbiologica Polonica

|

1995

|

tom 44

|

nr 2

19

Effect of phytohormones and tungsten on light-induced and nitrate-induced nitrate reductase activity of mustard cotyledons

63%

Saroop S. , Chanda S. V. , Singh Y. D.

Acta Physiologiae Plantarum

|

2000

|

tom 22

|

nr 4

20

Ontogenic variation of nodulation, nitrogen fixation and nitrogen assimilation in lentil [Lens culinaris Medic]. II. Nitrogenase, nitrate reductase and glutamine synthetase activities

63%

Awan M. F. M.

Acta Physiologiae Plantarum

|

1994

|

tom 16

|

nr 4