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  1. 1051 Biotechnologia

  2. 20 World News of Natural Sciences

  3. 6 Zeszyty Naukowe Towarzystwa Doktorantów Uniwersytetu Jagiellońskiego. Nauki Ścisłe

  4. 3 Progress on Chemistry and Application of Chitin and its Derivatives

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  1. 28 Grajek W.

  2. 19 Twardowski T.

  3. 17 Figlerowicz M.

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1

In vitro gynogenesis as a method for haploid plant production

100%
Mol R.
Biotechnologia
|
2003
|
issue 3
52-61
EN
This paper reviews last three decades of work on in vitro cultures of unpollinated ovaries or ovules. During in vitro gynogenesis, plants are produced from embryos or callus tissue of haploid (parhtenogenetic or apogamic) origin. Thus, in vitro gynogenesis offers an efficient method for plant breeders who want to obtain haploid plants and homozygous lines. Stability of DH-lines and very limited albinism of regenerated plants are major advantages of the method. The limiting factors are genotype effects in particular species and relatively high labour compared to another or microspore cultures. Since 1976, the studies on in vitro gynogenesis have been performed in 27 species including many crops. Furthermore, gynogenetic haploids have been routinely used in breeding programmes for sugar beet, onion and rice. Because of labour expenses, cultures of unpollinated ovaries or ovules are usually chosen when no other efficient method is available for haploid production in a given species.
2

Molecular basis for the degradation of aromatic xenobiotic compounds

100%
Gren I., Guzik U., Wojcieszynska D., Labuzek S.
Biotechnologia
|
2008
|
issue 2
58-67
EN
Aromatic compounds in the environment can be of natural or anthropological origins. Xenobiotic arenes are found to be weakly degraded because of the presence of stable aromatic ring (due to the delocalization of their p orbitals) and different constituents which can impede biodegradation rate. That's why the cleavage of aromatic ring by dioxygenases of bacterial origin is the critical step in removing of theses xenobiotics from environment. Also, monooxygenases play important role in biotransformation of the initial structure to one of the central intermediates: catechol, hydroquinone, protocatechuate or gentisate. In biodegradation of haloaromatics, dehalogenases are the essential enzymes in removing these xenobiotics.
3

Plant invertases ? physiological function, regulation of activity and application in biotechnology

100%
Hawrylak B., Wolska-Mitaszko B.
|
2007
|
issue 2
63-80
EN
Disaccharide sucrose plays important role in plants in photoassimilate partitioning, and as a carbon and energy source, it regulates cell metabolism, plant growth and development. Utilization of sucrose in most metabolic pathways is preceding by enzymatic cleavage of sucrose to monosaccharides. This cleavage is catalyzed by invertase and sucrose synthase. Hydrolysis of sucrose to glucose and fructose provides substrates to primary metabolism reactions proceed in plant cell. Because sugars in plants are not only nutrients molecules, but also regulate expression of genes, invertase can control cell division and plant development. Several types of invertases can exist in plant cells, which differ in their biochemical properties and cell localization. The rapid accumulation of information about their physiological function and regulation in planta has revealed the biotechnological potential of these proteins. This review focuses on recent advances in the properties and role of the identified plant invertases in the light of application for plant metabolic engineering.
4

Subtilisin embedded in TAC fibre - properties and application

100%
Trzmiel T., Szczesna-Antczak M., Rzyska M.
Biotechnologia
|
2001
|
issue 4
175-188
EN
The embodiment of subtilisin from Bacillus subtilis IBTC-3 in triacetylocellulose (TAC) fibre was studied. The fibre preparation of proteolytic activity 51.3 AmU/g was obtained with 16.6% of yield. The properties of subtilisin embedded in TAC fibre were investigated. The preparation showed optimal proteolytic activity at pH 9 and temperature 65-70C. It was stable in a wider range of pH and temperature than the native subtilisin. The KM value for haemoglobin was 2.6 ? 10-3 M. The TAC-fibre biocatalyst, in the fixed bed column, was successfully applied for hydrolysis of casein.
5

Influence of long-time continuous wine fermentation on morphological changes of yeast immobilized on foam glass

100%
Bonin S., Wzorek W.
Biotechnologia
|
2003
|
issue 4
167-181
EN
The aim of this work was to study the influence of long-time continuous wine fermentation on yeast morphology. The process of fermentation was carried out in medium of high sugar concentration (about 320 g/dm3), for 3,5 months, at 22C in 4 columns fermentor (4 series). In this experiment, wine yeast Saccharomyces bayanus strain S.o./1AD from the Collection of Pure Cultures of the Department of Food Biotechnology and Microbiology of Warsaw Agriculture University was used. Yeast was immobilized on foam glass. In this study, before and after immobilization the cells were examined by light microscopy, scanning electron microscopy and computer image analysis. It was stated that yeast after 3,5 months of continuous fermentation was bigger and showed morphological and intracellular changes in comparison with cells before this process. Before immobilization yeast was ovoid, single or budding cells. Various shapes of cells were observed after immobilization: elongated, in the shape of ?pear?, very big round and ?pseudomycelia?. In ?pseudomycelium?, the cells remained firmly connected by their cell walls and cytoplasm. In some cells, degeneration of cytoplasmic content was observed, too. These cells contained ?granularity?. The results show that long-time, continuous fermentation in high sugar medium causes negative changes of yeast cells.
6

Characteristics and purification of Bacillus polymyxa B-20 amylases

100%
Rodziewicz A.
Biotechnologia
|
2000
|
issue 1
49-55
EN
Bacillus polymyxa B-20 alpha- and beta-amylase were purified using a combination of acetone fractionations, ion-exchange chromatography and amonium sulfate precipitation. The a-amylase was purified 18-fold, to a specific activity of 1065 U/ mg. The enzyme had on optimal temperature at 70oC and was stable up to 50oC in presence of Ca++. A purified enzyme displayed maxima for activity of pH 6,8 and was inhibited by 1 mM EDTA. Maltose is predominantly produced from starch. The beta-amylase had pH optima at 5,6 (acetate buffer), temperature optima at 60oC, was stable pH range of 5,0 to 7,5 at temperature up to 45oC. Enzyme activity was inhibited by sulfhydryl reagents such as pCMB and Hg++. Both B.polymyxa B-20, alpha- and beta-amylase are maltogenic enzymes.
7

Intensification of carbohydrate changes in lignocellulose wastes during cultivation of fungi

100%
Lewandowska M., Bednarski W.
Biotechnologia
|
1999
|
issue 1
126-143
EN
This work reports the results on bioconversion of two lignocellulose wastes, i.e. wheat waste and faba bean hulls by fungi T. reesei and A. niger. The efficiency of lignocelluloses biodegradation after culturing the fungi was determined on the basis of the reduction of fibre content in the substrates, increase of protein in the preparations obtained, and the yield of protein biosynthesis. The experiments included the determination of the effect of various technological variables on the process intensification, i.e. method of culturing (shake- or surface culture), type of culture (single strains or mixed culture), raw material pre-treatment (physico-chemical or enzymatic treatment), and additional sources of carbon in the medium, inducing the biosynthesis of cellulases. In selected preparations after culturing the fungi, the changes in the composition of dietary fibre (soluble, SDF and insoluble, IDF) and simple sugars in the IDF fraction were analysed in detail.
8

Ethylene and plant defense response

100%
Handschuh L.
Biotechnologia
|
1999
|
issue 3
86-93
EN
The simplest plant growth and development hormone, ethylene, belongs (together with S.A. and JA) to key molecules governing the plant defense response. Production of ethylene is stimulated by wounding, flooding, metal ions, senescense and abscission processes, pathogene attack and ethylene itself. High level of ethylene induces the expression of many classes of pathogenesis-related proteins (PR). In order to properly function, ethylene must be precisely regulated, especially at the biosynthesis and signalling pathways. Two main enzymes involved in ethylene biosynthesis are ACC synthase and ACC oxidase. The ethylene signal transduction pathway is very complicated and needs to be further investigated. Ethylene binds to its receptors ETRs, then the signal is transduced to CTR1 and through phosforylating kinases cascades to EINs and EREBPs, directly binding to DNA GCC boxes. As a consequence, many PR proteins are activated.
9

Suitability and properties of beta-galactosidases from different sources

100%
Synowiecki J., Maciunska J.
Biotechnologia
|
2000
|
issue 1
117-123
EN
The article reviews the progress of investigations of b-galactosidases from microbial sources. These enzymes show great differences in optimal conditions of lactose hydrolysis and their utilisation create new possibilities to improve milk and milk by-products processing. Some beta-galactosidases from extreme thermophiles have significant activity above 100?C. Possible applications and interrelationship of both molecular structure and thermostability of these enzymes are also discussed.
10

Wheat tissue culture - a reviev

100%
Menke-Mielczarek I.
Biotechnologia
|
1997
|
issue 2
29-45
EN
Based on the available literature, this article describes the advances made in cell culture of wheat. The importance of the age and physiological stage of the explant is discussed. The influence of the genotype is observed. The role of the components of the induction medium and in particular the role of auxin and kinetin, is investigated. The development of off-white callus and long-term culture of this callus facilitates the establishment of suspension culture - a source of totipotent protoplasts. This paper also focuses on the techniques which are used to introduce genes into wheat plants and on the somaclonal variation that occurs in a population of plants regenerated after tissue culture.
11

Denitrification of drinking water in membrane bioreactor

100%
Burda W., Aniol A., Grajek W., Cyplik P., Malyszka T.
Biotechnologia
|
1999
|
issue 2
217-229
EN
The aim of this study was to define denitrification kinetics using bacteria Paracoccus denitrificans cultivated in membrane bioreactor equipped with microfilter module with ceramic cartridge with cut off 0,45 mm. Water used in experiments was loaded with very strong nitrate concentration reaching up to 6,0 g NO3-/L. Methanol was used as carbon source and was added in an amount 30 % higher than the one calculated stoichiometrically. The pH value of water was automatically adjusted to 7,0. As experimental variables the following parameters were tested: i) supplementation of water with some nutrients, including monopotassium phosphate and microelements: molybdenum, copper, ferric and magnesium ions, variable initial cell biomass concentration, ii) different cultivation methods: stationary batch fermentation in glass flasks and continuous fermentation in membrane bioreactor with cell recycling, iii) procedure of water suppl to bioreactor; namely, in a closed system container/membrane bioreactor, and in an open system with continuous water flow through membrane bioreactor. The results obtained in experimental fermentations showed that bacteria Paracoccus denitrificans efficiently removed nitrate ions from water. It was found that fermentation conditions significantly affected bacteria growth and denitrification rate. It was observed that addition of phosphate and microelements into drinking water significantly increased denitrification rate and cell growth. An important factor influencing denitrification rate was the initial cell concentration. However, the effect of that factor lost its significance with the fermentation time. Comparing the effect of fermentation conditions on the denitrification rate, an inhibiting effect of shear forces caused by lobar pump was observed. Upon continuous biodenitrification in membrane bioreactor with open water flow, a maximum volumetric nitrate reduction yield reached 1,7 g NO3- dm^3/ h and specific denitrification rate amounted to 0,0145 g NO3- /h/ g of cell dry matter. After three days of fermentation, cell concentration reached the value of 20-35 g dry matter per liter. On the basis of obtained the results, the mathematical models of cell growth kinetics, denitrification kinetics as well as the model of denitrification rate as a function of cell concentration have been proposed.
12

GMO -innovative biotechnology in 21st century medicine

100%
Twardowski T.
Biotechnologia
|
2009
|
issue 5
5-10
EN
Genetically modified organisms are the key step for innovative medicines. The innovative drugs in the 21st century will be in the majority of proteins, nucleic acids and their combinations. The critical issues in case of biopharmaceuticals are quality and reproducibility of production. These aspects are evident in biosimilars (generics) and protection of intellectual property rights.
13

The application of monoclonal antibodies to medical treatment

100%
Kurpisz M.
Biotechnologia
|
1993
|
issue 2
105-120
EN
In this review contemporary trends in the application of monoclonal antibodies are presented. There is discussed antibody reengineering for humanization of mouse monoclonal antibodies to avoid anti-globulin reaction of patient. Recent modifications of antibody fragments are also outlined. The most common antigenic structures exposed to antibody attack are characterized. Some aspects of human monoclonal antibody production are briefly described. Three most promising therapeutic antibodies - bispecific antibodies, immunotoxins, and radiolabeled immunoconjugates - are presented.
14

Evaluation of Thermus ruber as a source of thermostable (-glucosidase useful for production of glucose syrups

100%
Sinkiewicz I., Synowiecki J.
Biotechnologia
|
2009
|
issue 2
134-146
EN
Thermus ruber produces (-glucosidase detected in the crude extract of cell proteins. This enzyme exhibits optimum actiivity at 65(C and pH 6,0. The enzyme was stable within a range of pH 5.5 to 8.0 and in 65(C for 60 min. The rate of p-nitrophenol-(-D-glucopyranoside cleavage was higher than that for maltose. With maltotetraose, maltopentaose and maltohexaose, the hydrolysis rate decreased with increasing the molecular weight of the substrate. Our data suggest that the starch converting process could be improved using (-glucosidase from Thermus ruber.
15

Genetically engineered potato resistant to potato leafroll virus infection

100%
Palucha A., Chrzanowska M., Zagorski W., Hulanicka D.
Biotechnologia
|
1997
|
issue 4
38-47
EN
Binary plasmids carrying different fragments of the coat protein gene of potato leafroll luteovirus were constructed for transformation of commercial potato cultivar Bzura. Several transgenic plant lines were obtained and characterised. The resistance of transgenic plants to the virus was tested by inoculation with aphids or grafting. Selected transformants expressing viral RNA were resistant to virus challenge by viruliferous aphids. Expression of the antisense RNA prevented virus infection even after grafting with scions from infected plants.
16

Microbial resources of biotechnology - the oganization of culture collections

100%
Ilnicka-Olejniczak K.
Biotechnologia
|
1994
|
issue 4
126-139
EN
The organization and activities of the World Federation for Culture Colletions, the World Data Center, The European Culture Colletion Organization Microbial Strain Data Network and the Microbial Informtion Network Europe were described.Special attention was given to the activities of the Polish Culture Colletions.
17

Transformed root cultures of Arnica montana L. ? of secondary metabolites isolation

100%
Weremczuk-Jezyna I., Wysokinska H.
Biotechnologia
|
2004
|
issue 2
54-61
EN
The hairy roots of A. montana were achieved by the infection of sterile leaves with Agrobacterium rhizogenes (strain LBA 9402). The transformation was confirmed by opin and PCR analysis. In the investigation, the optimum contitions of Hairy roots growth were characterized. The best results were achieved in liquid Gamborg medium which included half-strenght macro- and microelements (1/2B5) and 50 g/l sucrose. Phytochemical analysis showed that hairy roots of A. montana produced arnifolin and chlorogenic acid.
18

Attempts to transform the killer factor of yeasts Saccharomyces cerevisiae to amylotytic yeasts Schwanniomyces occidentalis

100%
Stobinska H., Drewicz E., Kregiel D., Oberman H.
Biotechnologia
|
1997
|
issue 1
158-166
EN
The fermentation yeasts Saccharomyces cerevisiae capable of producing killer factor type K2 and amylolytic yeasts Schwanniomyces occidentalis were used to obtain the somatic hybrids by means of fusion protoplasts according to Fournier.The obtained hybrids showed amylolytic and fermentation activity.They also were characterized by the ability to form spores and to biosynthesize the killer factor.Their stability was dependent on the composition of the cultivation medium.
19

The utility of unconventional oxygenation of culture in simultaneousl production of inulinase and invertase by yeasts K. marxianus K-2

100%
Pielecki J., Targonski Z.
Biotechnologia
|
2003
|
issue 1
234-243
EN
In this study, the apparatus for continuous controlling of dissolved oxygen concentration in the culture media was used. The automatic dosing of hydrogen peroxide (decomposed to oxygen and water) was possible, and a significant increase of extracellular enzymatic activity of inulinase (2,5-fold) and invertase (1,5-fold) were obtained in comparison with the traditional aeration. It also minimizes contamination, lowers the expenses on power consumption on aeration and mixing, reduces foaming and, consequently, high cost of antifoam emulsion and bacteriological filters.
20

Fungus lipases and their activity in the hydrolisis reaction and in the synthesis of fatty acid esters

100%
Antczak T., Krystynowicz A., Galas E.
Biotechnologia
|
1995
|
issue 2
82-91
EN
Preparations of soluble and immobilized fungus lipases showing high catalityc acivity in hydrolysis of acyloglycerols in water, synthesis of esters of higher fatty acids in hydrolysis of acyloglycerols in water and synthsis of esters of higher fatty acids inorganic solvents milieu were obtained.The course of reaction andthe activity dependedon: the lipase source, the form of enzyme and the reaction milieu.The studied extacellular lipases, in a water - soluble form (especially R.nigricans lipase), exibited high activity in olive oil hydrolisis.The lipases were not active in esters synthesis in diphase system: water-organic solvent.Being drained by liophilization they demonstrated the activity in esters synthesis inorgnic solvents milieu.The endocellular lipases immobilized in situshowed the hihgest activity in the synthesis of esters in organic milieu.These enzymes can also be used for hydrolysis of acyloglycerols.The obtained liquid and immobilized mycelial preparations demonstrate activity which qualifies them for industrial scale application.
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