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Aktywność i stabilność katalazy immobilizowanej w kapsułkach alginianowych w aplikacjach przemysłowych

100%

Trusek-Holownia A.

Żywność Nauka Technologia Jakość

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2015

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tom 22

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nr 2

PL

Efektywną metodą zahamowania rozwoju zanieczyszczeń mikrobiologicznych (bakteryjnych i grzybowych) obecnych w wodzie pitnej, mleku czy w sokach jest dodanie nadtlenku wodoru. Technika ta nie jest w Polsce powszechnie stosowana, jest jednak dopuszczona w wielu krajach pod warunkiem całkowitego usunięcia dodanego nadtlenku wodoru przed dopuszczeniem produktu do spożycia lub do dalszych etapów przetwarzania. Szybką metodą usunięcia nadtlenku wodoru może być zastosowanie enzymu – katalazy. W celu możliwości wielokrotnego użycia preparatu enzymatycznego, jak i łatwej jego separacji z mieszaniny reakcyjnej, zaproponowano immobilizację katalazy w kapsułkach alginianowych. Przeanalizowano możliwość zastosowania otrzymanego preparatu do usuwania H₂O₂ dodanego do różnych płynów: wody, mleka, soków warzywnych. Określono stabilność preparatu w warunkach procesowych (11 i 24 °C) i w temperaturze przechowywania preparatu (4 °C). Wyznaczone w buforach o danym pH stałe równania kinetycznego zweryfikowano w badaniach wymienionych płynów. Na podstawie parametrów kinetycznych określono warunki do przeprowadzenia procesu o założonej wydajności. Zaproponowano proces okresowy z separacją preparatu na sitach. Podano czas procesu dla poszczególnych szarży. W przypadku, gdy temperatura procesu zostanie obniżona do 11 °C, czas reakcji musi być znacząco dłuższy, niemniej liczba przeprowadzonych szarży (z uwagi na zachowaną aktywność preparatu) rekompensuje dłuższy czas procesu. Prowadzenie reakcji w obniżonej temperaturze jest uzasadnione w przypadku, gdy medium oczyszczane jest przetrzymywane w warunkach chłodniczych, co zwykle ma miejsce. Temp. 11 °C jest najniższą wartością, w której stosowany enzym wykazuje aktywność.

EN

The addition of hydrogen peroxide is an efficient method to inhibit the growth of microbial contaminants (bacterial and fungal) present in drinking water, milk, or juice. This technique is not commonly applied in Poland, but it is allowed in many countries provided that the hydrogen peroxide added to the product is completely removed from it prior to its release for consumption or for further processing. A rapid method of removing hydrogen peroxide could be the use of a catalase enzyme. In order to make it possible to repeatedly use that enzyme preparation and to easily separate it from the reaction mixture, it was suggested to immobilize the catalase in alginate capsules. The potentiality of using the produced preparation for H₂O₂ removal was analyzed through adding it to various liquids: water, milk, and vegetable juices. The stability of the preparation was determined under the process conditions (11 and 24°C) and at a temperature for storing the preparation (4 °C). The values of the kinetic equation constants, determined in the buffers of a given pH value, were verified through the analyses of the above named liquids. Based on the kinetic parameters, the processing conditions were determined for a planned process efficiency. A batch process including separation on sieves was proposed. The time of individual process charges was given. In the case of decreasing the process temperature to 11°C, the reaction time must be significantly longer; however, the number of performed charges (because of the maintained activity of the preparation) balances the effect of a longer process time. Performing the reaction at a lower temperature is also valid in the case of keeping the medium being purified under the refrigeration conditions, which is usually the case. A temperature of 11°C is the lowest value, at which the enzyme applied is active.

2

Polymeric drug carriers—Control of the daily dose and therapy duration

63%

Trusek-Holownia A. , Jaworska P.

Biocybernetics and Biomedical Engineering

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2015

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tom Vol. 35, no. 3

192--197

EN

This study evaluates the mass release of cyanocobalamin with various drug carriers. Monolithic structures with a liquid core covering a thick (>150 μm) porous, polymer membrane are recommended. Membrane pore size should ensure easy diffusion of the drug molecules. The selection of the carrier's parameters to fit a required daily dose and therapy duration must consider the following criteria: 1′ the determination of its size (geometric surface); 2′ the number of carriers, if more than one is necessary; 3′ the thickness of membrane covering the carrier; and 4′ the mass of the loading drug. An algorithm to select these conjugated parameters to achieve the therapeutic threshold and duration of the drug effect was expanded upon. A system to constantly deliver drugs over days/weeks/months can be maintained if the loaded mass of the drug significantly exceeds its solubility in the carrier's core.

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Two-step treatment of harmful industrial wastewater: an analysis of microbial reactor with integrated membrane retention for benzene and toluene removal

63%

Trusek-Holownia A. , Noworyta A.

Polish Journal of Chemical Technology

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2015

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tom Vol. 17, nr 4

15--22

EN

Standards for highly toxic and carcinogenic pollutants impose strict guidelines, requiring values close to zero, regarding the degradation of such pollutants in industrial streams. In many cases, classic bioremoval processes fail. Therefore, we proposed a stream leaving the microbial membrane bioreactor (MBR) that is directed to an additional membrane separation mode (NF/RO). Under certain conditions, the integrated process not only benefits the environment but may also increase the profitability of the bioreactor operation. An appropriate model was developed and tested in which the bioremoval of benzene and toluene by Pseudomonas fluorescens was used as an example. This paper presents equations for selecting the operation parameters of the integrated system to achieve the expected degree of industrial wastewater purification.

4

Enzymatic synthesis of hydrophobic compounds integrated with membrane separation

63%

Noworyta A. , Trusek-Holownia A.

Chemical and Process Engineering

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2016

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tom Vol. 37, nr 1

15--27

EN

The enzymatic synthesis of a highly hydrophobic product (dipeptide precursor) in which the reaction is accompanied by the mass transfer of the reaction product to the organic phase and the substrates to the water phase is considered. Equations describing both continuous and batch processes are formulated. The range of variability in the operating parameters of such a bioreactor is specified, and the correlations reported in the literature to describe mass transfer in the membrane contactor are validated. The proposed process was verified experimentally, and good agreement between the determined and calculated concentrations was obtained in both phases.

5

Enhanced production of polygalacturonase in solid-state fermentation: selection of the process conditions, isolation and partial characterization of the enzyme

63%

Zaslona H. , Trusek-Holownia A.

Acta Biochimica Polonica

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2015

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tom 62

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nr 4

6

Biodegradation of whey waste in a continuous stirred-tank bioreactor

63%

Lech M. , Trusek-Holownia A.

Environment Protection Engineering

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2015

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tom Vol. 41, nr 4

97--107

EN

Post-production whey has a high concentration of proteins and lactose that has to be decreased 500-fold before disposal in the environment. The paper describes goat whey biodegradation in a continuous stirred tank reactor (CSTR) using a Bacillus licheniformis strain. The data obtained emphasize the effect of excess organic compounds on growth rate. Accordingly, the Luong equation was applied to describe the batch process while accounting for substrate inhibition; the constants vmax = 2.29·10–4 1/s, Km = 4.79 g/dm3, Ki = 6.03 g/dm3, and n = 1.1 were experimentally obtained. According to accepted theory, the continuous process can be expressed using Monod’s equation (only for the rising side of the kinetic graph) in a restricted range of substrate concentrations (for glucose, up to 2.16 g/dm3). The estimated values of the constants were vmax = 8.52·10–5 1/s and Km = 0.45 g/dm3. The selected strain effectively decreased the lactose content in whey. At residence times above 30 h, almost total decrease in lactose content was observed that met the requirements of the Polish Ministry of Environmental Protection. The biodegradation of proteins was much slower, but their content does not greatly influence the required BOD and COD values.

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Dobór układu reakcyjnego dla enzymatycznej syntezy dipeptydów

63%

Trusek-Holownia A. , Noworyta A.

Biotechnologia

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2000

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nr 1