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1

Immobilizowane alfa-amylazy i celulazy w zastosowaniach praktycznych

Chałupka Z.

Wiadomości Chemiczne

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2016

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[Z] 70, 5-6

369--389

EN

Today, more and more products made in biotechnological processes involving enzymes. The stability of the enzyme under process conditions are subjected to the immobilization on solid supports, which leads to a heterogeneous biocatalyst that can be used in several cycles or continuous processes. The article discusses the techniques presented in the literature immobilization of enzymes hydrolyzing starch and cellulose. Includes the method of immobilization in/on polymer and inorganic carriers and different ways of binding of the enzyme to a solid support. Particular attention is focused on mesoporous silica (mesoporous silica) (SBA-15) as a very attractive media for biocatalysts. Starch and cellulose are the main components of biomass, which is seen as an alternative raw material for ethanol production, i.e. second generation biofuels. Developing an effective biocatalyst for the conversion of biomass is the challenge of the XXI century.

2

Opracowanie metody oraz optymalizacja warunków immobilizacji inwertazy drożdżowej w żelu alginianowym

Oloś G., Zhuk O.

Proceedings of ECOpole

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2016

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Vol. 10, No. 2

749--756

PL

Zbadano wpływ różnych stężeń chlorku wapnia oraz czasu kondycjonowania inwertazy drożdżowej (EC 3.2.1.26) izolowanej z drożdży piekarniczych Saccharomyces cerevisiae immobilizowanej w żelu alginianowym. Z wykorzystanych w badaniach różnych stężeń chlorku wapnia (2, 5, 10 i 30%) najwyższą aktywność enzymatyczną uzyskano dla najwyższego wykorzystanego stężenia. Wykazano, że czas 15 minut kondycjonowania żelu alginianowego w chlorku wapnia prowadzi do najefektywniejszego immobilizowania inwertazy. Dodatkowo oceniono wpływ immobilizacji inwertazy drożdżowej na jej aktywność w odniesieniu do wolnej formy tego enzymu w szerokim zakresie pH (3,5; 4,0; 4,5; 5,0; 5,5; 6,0; 6,5) oraz temperatury (21, 36, 44, 49, 54, 59, 64 oraz 70°C). Aktywność enzymatyczną badano spektrofotometrycznie poprzez mierzenie przyrostu zredukowanej formy kwasu pikrynowego powstałej w obecności cukrów redukujących otrzymanych ze zhydrolizowanej przez inwertazę sacharozy. Spośród wykorzystanych różnych wartości temperatury i pH najwyższą wydajność immobilizowanej inwertazy wykazano dla 59°C i pH 4,5-5,0. Wykazano, że immobilizowana inwertaza zachowuje aktywność w szerszym zakresie pH i temperatury od formy wolnej (nieimmobilizowanej).

EN

The aim of this study was to evaluate the effect of the selected physical and chemical parameters of immobilization process of yeast invertase in alginate gel and to compere the enzymatic effectiveness of free and immobilizated enzyme. Yeast invertase enzyme was obtained from homogenated Saccharomyces cerevisiae cells and then centrifuged. It was later added into alginate gel solution and then the mixture was dripped into calcium chloride solution. The aim of my study was to find most optimal conditions for immobilization of studied enzyme, thus different concentrations of calcium chloride were used (2, 5, 10, 30%) and different conditioning time of alginate gel beads (5, 10, 15, 30, 60, 120 min). Additionally I compared effectiveness of already formed beads containing yeast invertase to its unimmobilized form in wide spectrum of temperature (21, 36, 44, 49, 54, 59, 64 and 70°C) as well as in different pH values (3.5; 4.0; 4.5; 5.0; 5.5; 6.0; 6.5). Activity of immobilized enzyme was measured spectrophotometrically by noticing changes in amount of reduced form of picric acid created in presence of reducing sugars gained from hydrolyzed sucrose by yeast invertase. Based on achieved results it has been shown that concentration of calcium chloride solution is more important than conditioning time of alginate gel beads containing immobilized enzyme. The highest effectiveness of immobilized enzyme was noticed for 60°C and between 4.5-5.0 pH. The immobilized form of yeast invertase was more stabile in wider spectrum of temperature and pH values compering to its unimmobilized form.

3

Enzymatic synthesis and characterization of polycaprolactone by using immobilized lipase onto a surface-modified renewable carrier

Ulker C., Gokalp N., Guvenilir Y.

Polish Journal of Chemical Technology

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2016

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Vol. 18, nr 3

134--140

EN

In the present study, rice husk ash, which is a renewable and abundant material, was utilized as a carrier for lipase immobilization for the first time. Poly (ε-caprolactone) synthesis was successfully achieved by the new enzymatic catalyst: Candida antarctica lipase B immobilized onto surface-modified rice husk ashes by covalent binding. It was aimed to obtain optimum polymerization conditions at which highest molecular weight was reached and characterize the polymer produced. Moreover, thermal stability and effectiveness of the new biocatalyst in non-aqueous media were also shown with successful polymerization reactions. In addition, by using the new enzyme preparation, ε-caprolactone was able to be polymerized even at 30°C, which was promising for an energy saving process. Consequently, this work provides a new alternative route for poly (ε-caprolactone) synthesis.

4

Hydroxyapatite as a support in protease immobilization process

Zdarta J., Budzinska K., Kolodziejczak-Radzimska A., Klapiszewski Ł., Siwinska-Stefanska K., Bartczak P., Piasecki A., Maciejewski H., Jesionowski T.

Physicochemical Problems of Mineral Processing

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2015

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Vol. 51, iss. 2

633--646

EN

Hydroxyapatite is used as a matrix for immobilization of protease from Aspergillus oryzae by a process of adsorption. The matrix obtained has the surface area of 26 m2/g and particles in the shape of flakes of diameters no greater than 650 nm. The efficiency of the proposed method was confirmed by the Fourier transform infrared spectroscopy, elemental analysis and by analysis of parameters of the pore structure of matrix and products after immobilization. On the basis of the Bradford method it was found that the greatest amount of enzyme (132 mg/g) was immobilized from a solution of initial enzyme concentration of 7 mg/cm3 after 24 h of the process.

5

A New Polymeric Support for Enzyme Immobilization for Biomicroreactors

Łukowska E., Pijanowska D., Chwojnowski A.

Polish Journal of Chemistry

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2008

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Vol. 82, nr 6

1265-1272

EN

Preparation of three kinds of the modified polyacrylonitrile supports for enzymes used in microreactors is described. The polyacrylonitrile supports were produced using the phase inversion method, with dimethylformamide as a solvent. For conversion of the cyano groups into the carboxylic ones, the raw supports were treated with sodium hydroxide or, alternatively using a new method, with ammonium persulfate. The modified supports were used for urease immobilization. The comparison of the immobilization effectiveness and activity of the immobilized and free enzyme is presented. The effectiveness of urease immobilization was evaluated by two methods, spectrophotometric and potentiometric with use of the flow-through microreactor. It was stated that the two-layer structure films with the polyvinylpyrrolidone, as well as using of the ammonium persulfate for surface modification, made a significant improvement in efficiency of the enzyme immobilization.

6

Polymer microspheres with immobilized enzymes and other proteins as materials for biosensors

Słomkowski S., Miksa B., Basinska T., Gambhir A.G., Kumar A., Malhotra B. D.

Biocybernetics and Biomedical Engineering

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2001

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Vol. 21, no. 4

49-65

EN

Poly(styrene/acrolein) (P(S/A)), poly(styrene/ !..-t-butoxy-!..-vinylbenzylpolyglycidol) (P(S/VB-PGL)), and poly(pyrrole/acrolein) (P(P/A)) microspheres were synthesized by emulsifier-Iess emulsion-precipitation copolymerization (P(S/A) and (P(S/VB-PGL)) and/or by sequential redox emulsion and precipitation polymerizations (P (P/A)). These microspheres were used for immobilization of glucose oxidase (GOD), urease (Urs) and human serum albumin (HSA). Activity of immobilized enzymes has been determined. Model biosensor elements, based on microsphere-enzyme conjugates, for oximetric (glucose) and potentiometric (urea) detection have been investigated. A new type of antibody (anti-HSA) detection system based on changes in electrophoretic mobility of microspheres with immobilized antigens (HSA) was designed and its effectiveness was experimentally verified.

PL

Mikrosfery z poli(styren/akroleiny) (P(S/A)), poli(styren/..-t-butoksy-..-winylobenzylpoliglicydolu) (P(S/VB-PGL) i poli(pirol/akroleiny) (P(P/A)) syntezowano stosując polimeryzację emulsyjną bez środków powierzchniowych. Na tych mikrosferach immobilizowano oksydazę glukozową (GOD), ureazę (Urs) i albuminę z ludzkiej surowicy (HSA). Określono aktywność immobilizowanych enzymów. Zbadano właściwości modelowych bioczujników wykorzystujących sprzężenie mikrosfer i enzymów: oksymetrycznego - detekcja glukozy i potencjometrycznego - dla mocznika. Wykonano i zbadano właściwości nowego układu detekcyjnego przeciwciała (przeciw - HSA) wykorzystującego elektroforetyczną ruchliwość mikrosfer z immobilizowanymi antygenami (HSA).