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Ethyl [1S, 2RS]-and [1S,2S]-2-[2-chloro-propanoyloxy]propanoate. Preparation and hydrolysis

100%

Polec I., Komorowska-Kulik J., Kielczewska A., Bombinska D., Legocki J.

Pestycydy

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2008

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nr 3-4

27-52

Ethyl (1S,2RS)-2-(2-chloropropanoyloxy)propanoate ((1S,2RS)-(I)) was obtained from rac-2-chloropropionyl chloride and ethyl L-lactate. (1S,2S)- (I) was also synthesized from (S)-2-chloropropionyl chloride and ethyl L-lactate with 93% d.e. (I) was undertaken hydrolysis by different media: NaOH/THF-H2O, Na2CO3/THF-H2O, LiOHxH2O/THF-H2O, 25% NaOH/H2O, and weakly acidic ion-exchange resin Amberlite IRC748 dispersion in MeOH. (1S,2RS)-2-(2-Chloropropanoyloxy) propanoic acid (II) diastereomers were identified as products of acidic hydrolysis with the ionic resin. GC/MS, HPLC and HPLC/MS analyses of resulted products are presented.

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Ethyl N,N-dimethyl- and N,N-dimethylamidophosphoric acids sodium salts. Preparation and hydrolysis

88%

Polec I., Huras B., Sas A., Kielczewska A., Legocki J.

Pestycydy

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2008

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nr 3-4

53-61

Sodium salts of ethyl N,N-dimethyl- and N,N-dimethylamidophosphoric acids I and II were obtained and their hydrolysis to respective acids was investigated. The salts and acids were characterized by spectral methods (MS, FT/IR, 1H, 13C, 31P NMR).

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The response of the double strand-specific nuclease V1 to Y-base removal in yeast tRNA(Phe)

88%

Marciniec T., Ciesiolka J., Krzyzosiak W.

Acta Biochimica Polonica

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1989

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tom 36

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nr 2

4

Preparation of nanocellulose by hydrolysis with ionic liquids and two-step hydrolysis with ionic liquids and enzymes

88%

Babicka M., Wozniak M., Szentner K., Borysiak S., Dwiecki K., Ratajczak I.

Annals of Warsaw University of Life Sciences - SGGW. Forestry and Wood Technology

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2021

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tom 116

5

Effect of enzymatic hydrolysis of plant pulp on chemical composition of juice obtained from it

88%

Baraniak B.

Applied Biology Communications. Lublin Scientific Center

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1992

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tom 02

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nr 3

6

Impact of hormonal imprinting on the hydrolysis time of the Feulgen reaction in Tetrahymena. Do nuclear level changes appear after imprinting?

75%

Kovacs P., Csaba G.

Acta Protozoologica

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1991

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tom 30

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nr 2

7

Mitochondrial adenosine triphosphatase from human placenta - inhibition by free magnesium ions of ITP hydrolysis

75%

Aleksandrowicz Z.

Acta Biochimica Polonica

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1994

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tom 41

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nr 1

The effects of Mg2+ and bicarbonate on the kinetics of ITP hydrolysis by soluble ATPase (Fi) from human placental mitochondria were studied. Increasing amounts of Mg2+ at fixed ITP concentration, caused a marked activation of Fi followed by inhibition at higher Mg2+ concentration. The appropriate substrate for the mitochondrial Fi seems to be the MglTP complex as almost no ITP was hydrolysed in the absence of magnesium. Mg2+ behaved as a competitive inhibitor towards the MglTP complex. In this respect the human placental enzyme differ from that from other sources such as yeast, beef liver or rat liver. The linearity of the plot presenting competitive inhibition by free Mg2+ of MglTP hydrolysis (in the presence of activating bicarbonate anion) suggests that both Mg2+ and MglTP bind to the same catalytic site (Km(MgITP) = 0.46 mM, Ki(Mg) = 4 mM). When bicarbonate was absent in the ITPase assay, placental Fi exhibited apparent negative cooperativity in the presence of 5 mM Mg2+, just as it did with MgATP as a substrate under similar conditions. Bicarbonate ions eliminated the negative cooperativity with respect to ITP (as the Hill coefficient of 0.46 was brought to approx. 1), and thus limited inhibition by free Mg2+. The results presented suggest that the concentration of free magnesium ions may be an important regulatory factor of the human placental Fi activity.

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Hydrolysis cyclic GMP in rat peritoneal macrophages

75%

Witwicka H., Kobialka M., Gorczyca W. A.

Acta Biochimica Polonica

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2002

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tom 49

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nr 4

Intact rat peritoneal macrophages (rPM) treated with 3-isobutyl-1-methylxanthine (IBMX), an inhibitor of phosphodiesterases (PDEs), accumulated more cGMP than untreated cells. A PDE activity toward [3H]cGMP was detected in the soluble and particulate fractions of rPM. The hydrolysis of cGMP was Ca2+ /calmodulin-independent but increased in the presence of cGMP excess. Similar results were obtained when3 [ 3H]cAMP was used as a substrate. The hydrolytic activity towards both nucleotides was inhibited in the presence of IBMX. Therefore, the PDEs of families 2,5,10 and 11 are potential candidates for cGMP hydrolysis in the rPM. They may not only regulate the cGMP level in a feedback-controlled way but also link cGMP-dependent pathways with those regulated by cAMP.

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Preperation of unbranched glucans by hydrolysis of starch of various botanical origin with pullulanase

75%

Kujawski M., Ziobro R., Gambus H.

Electronic Journal of Polish Agricultural Universities. Series Food Science and Technology

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2003

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tom 06

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nr 2

The use of pullulanase preparation was checked as a method to obtain long unbranched glucans from native starch. Different starch sources as well as various solubilisation procedures were tried in order to choose the optimal one. Dissolving in NaOH proved to be suitable for all starch sources, while autoclave should be avoided in case of cereal starches. Potato starch gave clear solutions irrespective of solubilisation method, which were highly susceptible to enzymatic attack. Basing on the results obtained by size exclusion chromatography it was concluded that the time of incubation with the enzyme needed to completely degrade amylopectin molecules is short in comparison to the time needed to hydrolyse all available glycosidic bonds.

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Purification and some characteristics of Penicillium citrinum lipase

75%

Maliszewska I. H.

Biotechnologia

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1997

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nr 3

11

Enzymatic hydrolysis of fibre from lucerne and tobacco

75%

Baraniak B., Bubicz M., Niezabitowska M.

Applied Biology Communications. Lublin Scientific Center

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1993

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tom 03

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nr 1-2

12

Evidence for the hydrolysis of topical applied liposomal lipids in human stratum corneum

75%

Zellmer S.

Cellular and Molecular Biology Letters

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2002

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tom 07

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nr 2

13

Structural and immunochemical studies on O-specific polysaccharide of Proteus penneri strain 14

75%

Sidorczyk Z., Swierzko A., Vinogradov E. V., Knirel Y. A., Shashkov A. S.

Archivum Immunologiae et Therapiae Experimentalis

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1994

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tom 42

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nr 3

14

Regulation of mammalian phospholipase D by ARF, RHOA, and an unidentified protein factor

75%

Nakamura S.

Cellular and Molecular Biology Letters

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1997

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tom 02

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nr 2

15

cGMP-dependent hydrolysis of cyclic nucleotides in peritoneal macrophages

75%

Wroblewska H., Kobialka M., Gorczyca W. A.

Cellular and Molecular Biology Letters

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2002

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tom 07

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nr Suppl.

16

Ocena podatności białek serwatkowych na działanie zewnątrzkomórkowych proteaz drożdży Yarrowia lipolytica

63%

Babij K., Dabrowska A., Szoltysik M., Pokora M., Szmyt A., Zambrowicz A., Chrzanowska J.

Acta Scientiarum Polonorum. Biotechnologia

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2013

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tom 12

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nr 3

Celem podjętych w pracy badań była ocena podatności wybranych białek serwatkowych na działanie zewnątrzkomórkowych proteaz drożdży Yarrowia lipolyti- ca i określenie ich potencjalnej przydatności technologicznej w procesie enzymatycznej hydrolizy. Do badań wykorzystano zarówno aktywną w środowisku kwaśnym proteazę aspartylową, a także działającą w środowisku alkalicznym proteazę serynową. Hydrolizie poddano a-laktoalbuminę, P-laktoglobulinę oraz dostępny w handlu koncentrat białek serwatkowych (WPC-80). Reakcję hydrolizy prowadzono w temperaturze 37°C, w pH 3,0 (dla proteazy aspartylowej) i w pH 8,0 (dla proteazy serynowej), wprowadzając enzym w dawce 10 U/mg białka substratowego. Postęp proteolizy analizowano ilościowo poprzez oznaczenie stopnia hydrolizy (DH%) i przyrost wolnych grup aminowych oraz jakościowo, tj. elektroforetycznie, a także wykonując rozdział frakcji białkowo-peptydowych przy wykorzystaniu wysoko sprawnej chromatografii cieczowej w układzie odwróconych faz (RP-HPLC). W puli wszystkich przetestowanych wariantów badawczych najwyższy poziom degradacji sięgający 39% uzyskano w roztworach P-laktoglobuliny trawionych drożdżową protezą serynową.

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Comparison of lipolytic activity of yeast strains isolated from Rokpol cheese

63%

Szoltyski M., Juszczyk P., Czajgucka A., Zarowska B., Dabrowska A., Polomska X., Babij K., Wojtatowicz J., Chrzanowska J.

Acta Scientiarum Polonorum. Biotechnologia

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2012

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tom 11

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nr 2

Lipolytic activity of seven yeast strains: Candida famata MI1a, C. intermedia BI2a, C. kefyr PII1b, C. sphaerica FII7a, Geotrichum penicillatum EII6a, Saccharomy- ces kluyveri BII3a and Yarrowia lipolytica PII6a was investigated. These strains representing yeast species occurring in mould cheese Rokpol are potential cheese co-starters. The extra and intracellular lipolytic activity of the yeast was analyzed against tributyrine and p-nitrophenyl derivatives of fatty acids. Also their ability to hydrolyze bovine milk fat was assayed. It was shown that generally activity of extracellular yeast lipases were higher than of intracellular enzymes. The most lipolytic were strains Y. lipolytica PII6a and C. sphaeri- ca FII7a, which preferentially hydrolyzed butyrate p-nitrophenyl derivative and release the highest amounts of oleic acid from milk fat.

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