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Wyświetlanie 1-8 z 8
Tytuł:
Proces niskotemperaturowej biokatalizy na przykładzie grzybowej biotransformacji [alfa]-pinenu
Low-temperature biocatalysis as an example of microbial biotransformation of alpha-pinene
Autorzy:
Skowroński, J.
Trytek, M.
Fiedurek, J.
Powiązania:
https://bibliotekanauki.pl/articles/256660.pdf
Data publikacji:
2013
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Technologii Eksploatacji - Państwowy Instytut Badawczy
Tematy:
biokataliza
biotransformacja
drobnoustroje psychrotroficzne
biocatalysis
biotransformation
psychrotrophic microorganisms
Opis:
Katalizatory warunkują przebieg oraz odpowiednią wydajność wielu reakcji chemicznych. Przemiany biochemiczne w większości przypadków katalizowane są z udziałem enzymów. Szczególne cechy biokatalizatorów są powszechnie wykorzystywane w przemyśle, a w ostatnich latach drobnoustroje ekstremofilne, adaptowane do skrajnych warunków abiotycznych, wzbudzają duże zainteresowanie licznej grupy badaczy. Wyjątkowe predyspozycje biokatalizatora psychrotroficznego z dobrymi efektami zostały wykorzystane w procesie biotransformacji a-pinenu do werbenolu i werbenonu, będących cennymi związkami smakowo-zapachowymi stosowanymi w branży spożywczej i kosmetycznej. Uzyskane wyniki (sumaryczne stężenie produktów przekraczające 0,5 g/dm3) stanowią obiecującą perspektywę wykorzystania tego typu procesów w większej skali (ponadlaboratoryjnej).
Many chemical reactions and their appropriate performance depend on catalysis. Most biochemical reactions are catalysed by enzymes. Special features of these biocatalysts are commonly employed in industry and current researches are focused on psychrotrophic microorganisms. These unique organisms can be a rich source of useful biocatalysts for biotransformation of a-pinene to verbenol and verbenone - valuable compounds used as flavours and fragrances. Results obtained in this study are promising for further application in the large scale.
Źródło:
Problemy Eksploatacji; 2013, 1; 101-111
1232-9312
Pojawia się w:
Problemy Eksploatacji
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Biokatalizatory i biopolimery w aspekcie zrównoważonej chemii
Biocatalysts and biopolymers in the aspect of sustainable chemistry
Autorzy:
Jesionowski, Teofil
Klapiszewski, Łukasz
Zdarta, Jakub
Powiązania:
https://bibliotekanauki.pl/articles/1853728.pdf
Data publikacji:
2021
Wydawca:
Polskie Towarzystwo Chemiczne
Tematy:
zielona chemia
ochrona środowiska
biokataliza
biopolimery
green chemistry
environmental protection
biocatalysis
biopolymers
Opis:
The rapid development of industry, apart from the obvious benefits, also leads to a significant increase in the level of environmental pollution, which is related not only to the use of harmful substances in the production process, but also to the production of significant amounts of by-products and wastes, which pose a serious threat to the environment as well as to the health and the life of living organisms. There is therefore a need to limit the use of toxic substances at every stage of production, and where this is not possible, appropriate waste management and the development of effective methods of harmful substances removal. In this respect, it seems crucial to introduce the principles of Green Chemistry as widely as possible. Green Chemistry is a concept whose main assumptions focus on designing and conducting chemical processes in a way that minimizes the use and formation of harmful substances as much as possible. This staretgy is based on twelve principles that overlap with the main assumptions of environmental chemistry to improve environmental protection and reduce pollution. There are many techniques and methods that fit into the assumptions of the broadly understood Green Chemistry, the implementation of which allows for sustainable management of post-production waste and by-products as well as their effective disposal. One of such concepts assumes the use of waste substances as a valuable raw material, not only for energy, but above all as a precursor and/or component for the production of innovative materials with high utility potential. Another idea is the use of enzymes, i.e. natural biocatalysts that allow chemical transformations to be carried out under mild process conditions, without the need to use harmful solvents. What's more, enzymes can be used not only at the stage of conversion/synthesis of substrates, but they can also be efficient tools for removing harmful substances. Hence, it seems necessary to undertake attempts aimed at the widest possible management of waste substances, as well as conduct research, the effect of which is the production of functional biocatalytic systems for various applications.
Źródło:
Wiadomości Chemiczne; 2021, 75, 9-10; 1241-1267
0043-5104
2300-0295
Pojawia się w:
Wiadomości Chemiczne
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Wpływ błony komórkowej na optymalne profile temperatury w procesie biotransformacji z równoległą dezaktywacją wewnątrzkomórkowego enzymu
Effect of cell membrane on optimal temperature profiles in the biotransformation with parallel endoenzyme deactivation
Autorzy:
Grubecki, I.
Powiązania:
https://bibliotekanauki.pl/articles/2073087.pdf
Data publikacji:
2015
Wydawca:
Stowarzyszenie Inżynierów i Techników Mechaników Polskich
Tematy:
biokataliza
efektywność
dezaktywacja biokatalizatora
optymalny profil temperatury
biocatalysis
effectiveness
biocatalyst deactivation
optimal temperature profile
Opis:
Rozważono okresowy proces biotransformacji przebiegający w obecności komórek drobnoustrojów wykazujących aktywność enzymu ulegającego dezaktywacji równoległej. W oparciu o klasyczną metodę rachunku wariacyjnego określono optymalne warunki temperaturowe zapewniające minimalny czas przebiegu procesu. Wykazano, że zastosowanie komórek drobnoustrojów spowalnia szybkość przebiegu rozkładu nadtlenku wodoru powodując przesunięcie początkowej temperatury profilów optymalnych w kierunku wyższych wartości. Przesuniecie to jest tym wyraźniejsze, im niższa jest przenikalność błony komórkowej. W konsekwencji obserwuje wydłużenie czasu przebiegu procesu optymalnego, przy czym dolne ograniczenie temperaturowe staje się nieaktywne.
A batch biotransformation process running in the presence of microorganisms cells revealing a specified enzyme activity was considered. The parallel deactivation of enzyme was taken into account. Based on variational calculus computations the optimal temperature conditions ensuring minimum duration time were determined. It was proved that the application of microorganisms cells results in slowing down the reaction rate and shifting the initial temperature of stationary profile to higher values. They are more pronounced when the lower is the permeability of membrane cell. In consequence, the extension of process duration time is observed along the sections of optimal profile while the lower temperature constraint usually becomes inactive
Źródło:
Inżynieria i Aparatura Chemiczna; 2015, 3; 87--89
0368-0827
Pojawia się w:
Inżynieria i Aparatura Chemiczna
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Przemysłowe zastosowania lipaz w syntezie związków o wysokiej wartości dodanej – 85 lat katalizy enzymatycznej lipazami. Część 2
Industrial applications of lipases in the synthesis of high added-value chemicals – 85 years of lipase-based enzymatic catalysis. Part 2
Autorzy:
Borowiecki, P.
Powiązania:
https://bibliotekanauki.pl/articles/172213.pdf
Data publikacji:
2015
Wydawca:
Polskie Towarzystwo Chemiczne
Tematy:
lipazy
zastosowania przemysłowe
biokataliza
związki enancjomerycznie czyste
lipases
industrial applications
biocatalysis
enantiomerically pure compounds
Opis:
Biotransformations are processes, in which chemical reactions are catalyzed by isolated enzymes or whole cells containing them. Among the biocatalysts, lipases are the most commonly used chiral selectors that exhibit high chemo-, regio-, and stereo-selectivity toward wide spectrum of organic compounds of xenobiothic nature. Moreover, lipases are very stable and active in organic solvents, as well as in neat solvents or in supercritical fluids in the absence of added water. Biotransformations by using lipases can be carried out at high substrate concentrations, at ambient temperature and neutral pH, without need for addition of cofactors, application of high pressures, extremely harsh reaction conditions or complex chemical apparatus. In addition, processes based on efficient biocatalytic technologies has proven to be beneficial for the chemical industry, as the lipases are able to catalyze reactions, which are not easily conducted by classical methods or in other cases allow reactions, which can replace several chemical steps. The above mentioned features of lipase-based biotransformations often cause significant improvement in energy efficiency (savings), and lead to a reduction in waste generation thereby making manufacturing processes even more economically attractive and environmentally acceptable. Since the mid-1980s the use of biotransformations with lipases in industry for the production of high added-value compounds, including pharmaceuticals, vitamins, cosmetics, fragrances and flavors, diagnostic preparations and therapeutics, high-tonnage preparation of agrochemicals, modified foods, nutraceuticals, detergents, polymers, advanced materials and biofuels has steadily increased. In this part of the review article on industrial applications of lipases, next group of popularly utilized enzymes relevant for the production of high added-value chemicals are described. It was also shown on several examples that enzymatic catalysis can significantly simplify manufacturing processes of complex structures being green and economical alternative for conventional chemical-based processes. Keywords:
Źródło:
Wiadomości Chemiczne; 2015, 69, 5-6; 431-463
0043-5104
2300-0295
Pojawia się w:
Wiadomości Chemiczne
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Zastosowania enzymów z tkanek zwierzęcych w syntezie organicznej i biokatalizie. Część I. Hydrolazy
Applications of hydrolases from animal tissues in organic synthesis
Autorzy:
Hibner, H.
Ostaszewski, R.
Powiązania:
https://bibliotekanauki.pl/articles/172016.pdf
Data publikacji:
2011
Wydawca:
Polskie Towarzystwo Chemiczne
Tematy:
enzymy zwierzęce
biokataliza
synteza organiczna
zastosowania hydrolaz
animal enzymes
biocatalysis
organic synthesis
applications of hydrolases
Opis:
This work presents systematically enzymes which can be obtained form animal tissue and their applications in synthesis of pharmaceuticals and nonracemic organic compounds. It lays out similarities in procedures of isolation and purification of particular enzymes. Such procedures usually are so simple that they can be used in every industrial or research laboratory. Most animal enzymes are well-investigated and their structures and substrate specificity are known. They are used as biocatalysts in many chemical processes. Others were used in one or a few reactions but their natural substrates and biochemical properties are described. Trials of predicting potential applications of such enzymes and other substrates for them were done. In this part typical applications of hydrolases: lipases (porcine pancreatic lipase [8–17], lamb pregastric lipase [22]), esterases (porcine, horse liver esterase, liver acetone powders [34–43, 46]), L-aminoacylase [48, 49], pepsin [56], trypsin [58, 59], imidase [52, 53], aldohexose hydrolases [60, 62-64], nucleotide pyrophosphatase [65]; were described. Also examples of immobilized [10, 32] or recombined [49] enzymes are given in the text. These modifications enhance catalytic properties or reduce costs of using enzymes. In practical applications a biocatalytic effect of enzymes from animal sources is often compared with microbial ones. This text is focused on processes where animal enzymes gave much better results (yield and enantioselectivity) than microorganisms. They are also proper, unlike whole microorganisms, to investigate and computer analysis of mechanism of the reaction. Enzymes isolated from animal tissues usually have well-defined structure of active site which is a key to predict mechanisms.
Źródło:
Wiadomości Chemiczne; 2011, 65, 7-8; 557-583
0043-5104
2300-0295
Pojawia się w:
Wiadomości Chemiczne
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Zastosowania wybranych enzymów z tkanek zwierzęcych w syntezie organicznej i biokatalizie. Część II. Oksydoreduktazy, transferazy, liazy, izomerazy
Applications of enzymes from animal tissues in organic synthesis, Part 2
Autorzy:
Hibner, H.
Ostaszewski, R.
Powiązania:
https://bibliotekanauki.pl/articles/172018.pdf
Data publikacji:
2011
Wydawca:
Polskie Towarzystwo Chemiczne
Tematy:
enzymy zwierzęce
biokataliza
synteza organiczna
zastosowania enzymów
animal enzymes
biocatalysis
organic synthesis
application of enzymes
Opis:
This work shows systematically known types of animal enzymes and their applications in synthesis of pharmaceuticals and nonracemic organic compounds. It lays out similarities in procedures of isolation and purification of particular enzymes. Such procedures usually are so simple that they can be used in every industrial or research laboratory. Most animal enzymes are well-investigated and their structures and substrate specificity are known. They are used as biocatalysts in many chemical processes. Others were used in one or a few reactions but their natural substrates and biochemical properties are described. Trials of predicting potential applications of such enzymes and other substrates for them were performed. Typical applications of: – Oxidoreductases: horse liver alcohol dehydrogenase [3–13], lactate dehydrogenase [16–18], glutamate dehydrogenase [19, 20], carbonyl reductase [24], catalase [27]; – Transferases: transaldolase [29], galactosyltransferase [30], UDP-glucuronosyltransferase [31], fucosyltransferase [34], farnesyl diphosphate synthase [35]; – Lyases: DOPA decarboxylase [38, 39], aldolase [42]; – Isomerases: N-acyl-D-glucosamine 2-epimerase [44] were described. Also examples of or recombined [24, 39, 44] enzymes are given in the text. These modifications enhance catalytic properties or reduce costs of using enzymes. In practical applications a biocatalytic effect of enzymes from animal sources is often compared with microbial ones. This text is focused on processes where animal enzymes gave much better results (yield and enantioselectivity) than microorganisms. They are also proper, unlike whole microorganisms, to investigate and computer analysis of mechanism of the reaction. Enzymes isolated from animal tissues usually have well-defined structure of active site which is a key to predict mechanisms. A quantitative analysis of applications of these enzymes was performed. Among animal enzymes hydrolases and oxidoreductases have found the most applications in synthesis. Transferases are also often used. Other classes of enzymes seldom act as biocatalysts. It is general tendency, true also in relation to microbial and plant enzymes.
Źródło:
Wiadomości Chemiczne; 2011, 65, 7-8; 585-607
0043-5104
2300-0295
Pojawia się w:
Wiadomości Chemiczne
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Biokatalityczne metody otrzymywania nieracemicznych alkoholi aryloallilowych
Biocatalytic methods for preparation of nonracemic arylallylic alcohols
Autorzy:
Szymkuć, S.
Ostaszewski, R.
Powiązania:
https://bibliotekanauki.pl/articles/172469.pdf
Data publikacji:
2012
Wydawca:
Polskie Towarzystwo Chemiczne
Tematy:
biokataliza
nieracemiczne alkohole aryloallilowe
synteza organiczna
enzymy
mikroorganizmy
biocatalysis
nonracemic arylallylic alcohols
organic synthesis
enzymes
microorganisms
Opis:
Different methods for preparing nonracemic arylallylic alcohols are presented in this work. A key feature was an application the biocatalyst as a mean to obtain final products. These compounds play an important role in pharmaceutical industry, because they are substrates in the synthesis of various important therapeutics [1–3]. Methods presented in this work are divided into five main groups: 1. enantioselective hydroxylation, 2. microbiological deracemization, 3. enzymatic kinetic resolution, 4. enzymatic dynamic kinetic resolution, 5. enantioselective reduction. First two methods use only microorganisms like bacteria [4, 5, 10], fungi [6–8] or yeasts [11] as biocatalysts. Owing to the metabolic processes in the cells it was possible to obtain nonracemic arylallylic alcohol (results for method 2 are presented in Table 1). Unfortunately, the data were insufficient to create direct correlation between values of enantiomeric excess and types of applied microorganisms. Methods 3 and 4 used only isolated enzymes as biocatalysts. They belong to two classes: hydrolases and oxidoreductases. Oxidoreductases were used in the enzymatic kinetic resolution based on the enantioselective oxidation [28] of one enantiomer of the racemic arylallylic alcohol. Nevertheless, hydrolases [12–27], mainly lipases, isolated from microorganisms are enzymes of common use in enzymatic kinetic resolution. Owing to this method it was possible to obtain final products with excellent enantioselectivity (results are presented in Tables 2 and 3). Because kinetic resolution and dynamic kinetic resolution are related processes, in most cases similar enzymes are used. The choice of lipases as biocatalysts for method 4 was caused by the fact that they are able to catalyze enantioselective transesterification of arylallylic alcohols or their acetates. Furthermore, racemization is very important factor for efficacy of dynamic kinetic resolution processes. In most cases they are catalyzed by different types of complexes based on palladium [30, 31] and ruthenium [32, 34]. Final products prepared by this method had very high enantiomeric excesses and yields up to 93% (results are presented in Tables 4 and 5). The only method, presented in this work, that allowed to use both enzymes [39–41] and microorganisms [35–38] as biocatalysts, was enantioselective reduction. This method allows to obtain nonracemic arylallylic alcohols with excellent enantiomeric excess and yields up to 85% (results are presented in Table 6). In summary, all methods presented in this work show the advantages of biocatalysis as an alternative route to traditional chemical method
Źródło:
Wiadomości Chemiczne; 2012, 66, 1-2; 93-118
0043-5104
2300-0295
Pojawia się w:
Wiadomości Chemiczne
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Przemysłowe zastosowania lipaz w syntezie związków o wysokiej wartości dodanej – 85 lat katalizy enzymatycznej lipazami. Część 1
Industrial applications of lipases in the synthesis of high added-value chemicals – 85 years of lipase-based enzymatic catalysis. Part 1
Autorzy:
Borowiecki, P.
Powiązania:
https://bibliotekanauki.pl/articles/171564.pdf
Data publikacji:
2015
Wydawca:
Polskie Towarzystwo Chemiczne
Tematy:
lipazy
lipaza B Candida antarctica
CAL-B
lipaza Burkholderia cepacia
BCL
zastosowania przemysłowe
biokataliza
związki enancjomerycznie czyste
Candida antarctica lipase B
Burkholderia cepacia lipase
industrial applications
biocatalysis
enantiomerically pure compounds
Opis:
Lipases (EC 3.1.1.3; triacylglycerol acylhydrolases) are the most commonly used enzymes in biotransformations of organic compounds. In living organisms lipases catalyze hydrolysis of higher fatty acid esters of glycerol, thus fulfill an essential function in metabolism of lipids (e.g. fats and oils) and lipoproteins. This year marks 125 years since J.R. Green has identified and described the first lipase isolated from germinated castor-oil beans (Ricinus communis L.) in the form of an extract showing hydrolytic properties. Plants, as well as bacteria are able to produce lipases what was reported in 1901 by Dutch scientist ‒ Christiaan Eijkman. Lipases are also produced by fungi, yeasts, and various organs of higher organisms. A strong foundation, which had a huge impact on the development of global lipase-mediated biotransformations was the discovery made in 1935 and described in Biochemistry Journal and Biochemische Zeitschrift by Polish biochemist- -enzymologist Ernest Alexander Sym (1893-1950) that these enzymes retain almost full catalytic activity even in nearly anhydrous organic solvents. This was exactly fifty years before Russian chemist Alexander Klibanov in 1985 described a lipase- -catalyzed reaction carried out in organic solvents. Since that moment, lipases have became extremely popular in both academic and industrial usage, nowadays being the most important among all biocatalysts used in biochemical processes carried out on an industrial scale. The purpose of this article is to provide a brief characterization of the two most widely used in industrial biotransformations lipases ‒ lipase B from Candida antarctica (CAL-B) and lipase from Burkholderia cepacia (BCL) ‒ and familiarize the readers with the issues of biotechnological processes catalyzed by them. The specifics of a range of industrial applications based on lipase catalysis, including the chemical, pharmaceutical, cosmetic and food industries are also discussed. Keywords:
Źródło:
Wiadomości Chemiczne; 2015, 69, 5-6; 391-430
0043-5104
2300-0295
Pojawia się w:
Wiadomości Chemiczne
Dostawca treści:
Biblioteka Nauki
Artykuł
    Wyświetlanie 1-8 z 8

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