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PL
Przedstawiono wyniki analizy adsorpcji białek zawartych w przemysłowym celulolitycznym preparacie enzymatycznym na poddanej obróbce wstępnej biomasie słomy kukurydzianej. Słoma kukurydziana i wyizolowana z niej lignina zostały użyte jako substraty w procesie enzymatycznego uwalniania cukrów prostych. Obróbkę wstępną biomasy prowadzono w środowisku alkalicznego 2-proc. roztworu H₂O₂ (pH 11,5). Wyznaczono wydajność hydrolizy glukanów (uzyskano 80,5%) i ksylanów (88,2%), stanowiących frakcje wstępnie obrobionej biomasy. Wyniki badań adsorpcji białek enzymatycznych na cząstkach surowca oraz ligninie opisano modelami izotermy Langmuira. Na podstawie tego modelu wyznaczono izotermy adsorpcji enzymów na polisacharydach zawartych w biomasie surowca.
EN
Corn straw biomass was pretreated with H₂O2₂ in alk. medium and then hydrolyzed in presence of a com. enzyme formulation at 50°C to produce glucose and xylose (yields 80.5% and 88.2%, resp.). The adsorption of enzymes on the raw material was described with Langmuir model isotherms.
2
Content available remote Badanie szybkości absorpcji tlenu w bioreaktorze z mieszaniem typu wave
PL
Przedstawiono wyniki pomiarów szybkości absorpcji tlenu z mieszaniny gazowej N2O2 w H2O w bioreaktorze z mieszaniem typu wave. Celem pracy była identyfikacja czynników wpływających na szybkość transportu tlenu do fazy ciekłej. Uzyskane wyniki doświadczalne wskazują, że szybkość absorpcji O2 w wodzie wzrasta wraz ze wzrostem wartości badanych parametrów operacyjnych: kąta i częstotliwości wychyleń platformy, przepływu fazy gazowej, objętości cieczy i prężności tlenu w gazie. Kontrola powyższych parametrów umożliwia uzyskanie odpowiednich warunków do hodowli wrażliwego materiału biologicznego.
EN
The results of measurements of O2 absorption rate from the N2O2 gas mixture in H2O in a bioreactor with wave-induced mixing are presented. The aim of this work was to identify the factors influencing on the rate of O2 transport to the liquid phase. The results show that the rate of O2 absorption in H2 increases with the increase of operating parameters values: angle and frequency of oscillations of the platform, gas flow rate, liquid volume, and O2 partial pressure. Controlling of the above parameters makes it possible to obtain suitable conditions for fragile biomass culture.
PL
Przedyskutowano intensyfikację napowietrzania fazy ciekłej w bioreaktorze typu single-use z mieszaniem typu wave na przykładzie reaktora ReadyToProcess WAVE™25 z polimerowym naczyniem hodowlanym o objętości 2 dm3. Wyróżniono dwie grupy czynników procesowych wpływających na efektywność napowietrzania: parametry dotyczące gazu i fazy ciekłej oraz parametry związane z falą generowaną w aparacie. Dla zbadanych wariantów napowietrzania fazy ciekłej uzyskano równowagę termodynamiczną O-2-woda. Potwierdzono aplikacyjność reaktora WAVE™25 do realizacji bioprocesów z komórkami o metabolizmie tlenowym.
EN
Intensification of liquid phase oxygenation in a single-use bioreactor with wave-induced mixing, i.e. ReadyToProcess WAVE™25 system equipped with 2 dm3 culture bag has been discussed. Two groups of process factors influencing on oxygenation effectiveness have been recognized: parameters related to gas and liquid phases, and parameters related to the wave induced inside the culture bag. The O-2-water thermodynamic equilibrium has been obtained for all studied variants of oxygenation process. The applicability of the WAVE™25 system in oxygen-dependent bioprocesses has been confirmed.
4
Content available remote Enzymatic activity of some industrially-applied cellulolytic enzyme preparations
EN
Enzymatic hydrolysis is the essential step in the production of 2nd generation biofuels made from lignocellulosic biomass, i.e. agricultural or forestry solid wastes. The enzyme-catalysed robust degradation of cellulose and hemicellulose to monosaccharides requires the synergistic action of the independent types of highly-specific enzymes, usually offered as ready-to-use preparations. The basic aim of the study was to experimentally determine the enzymatic activity of two widely industrially-applied, commercially available cellulolytic enzyme preparations: (i) Cellic® CTec2 and (ii) the mixture of Celluclast® 1.5L and Novozyme 188, in the hydrolysis of pre-treated lignocellulosic biomass, i.e. (a) energetic willow and (b) rye straw, or untreated (c) cellulose paper as well, used as feedstocks. Before the hydrolysis, every kind of utilized lignocellulosic biomass was subjected to alkaline-based (10% NaOH) pre-treatment at high-temperature (121°C) and overpressure (0.1 MPa) conditions. The influence of the type of applied enzymes, as well as their concentration, on the effectiveness of hydrolysis was quantitatively evaluated, and finally the enzyme activities were determined for each of tested cellulolytic enzyme preparations.
EN
One of the actual challenges in tissue engineering applications is to efficiently produce as high of number of cells as it is only possible, in the shortest time. In static cultures, the production of animal cell biomass in integrated forms (i.e. aggregates, inoculated scaffolds) is limited due to inefficient diffusion of culture medium components observed in such non-mixed culture systems, especially in the case of cell-inoculated fiber-based dense 3D scaffolds, inside which the intensification of mass transfer is particularly important. The applicability of a prototyped, small-scale, continuously wave-induced agitated system for intensification of anchorage-dependent CP5 chondrocytes proliferation outside and inside three-dimensional poly(lactic acid) (PLA) scaffolds has been discussed. Fibrous PLA-based constructs have been inoculated with CP5 cells and then maintained in two independent incubation systems: (i) non-agitated conditions and (ii) culture with wave-induced agitation. Significantly higher values of the volumetric glucose consumption rate have been noted for the system with the wave-induced agitation. The advantage of the presented wave-induced agitation culture system has been confirmed by lower activity of lactate dehydrogenase (LDH) released from the cells in the samples of culture medium harvested from the agitated cultures, in contrast to rather high values of LDH activity measured for static conditions. Results of the proceeded experiments and their analysis clearly exhibited the feasibility of the culture system supported with continuously wave-induced agitation for robust proliferation of the CP5 chondrocytes on PLA-based structures. Aside from the practicability of the prototyped system, we believe that it could also be applied as a standard method offering advantages for all types of the daily routine laboratory-scale animal cell cultures utilizing various fiber-based biomaterials, with the use of only regular laboratory devices.
6
Content available remote Innowacyjny system renowacji obiektów wodno-kanalizacyjnych
PL
Nowoczesne, bezwykopowe metody renowacji obiektów wodno-kanalizacyjnych pozwalają na znaczne skrócenie czasu potrzebnego na wykonanie prac, a dodatkowo umożliwiają ich przeprowadzenie bez znaczącej ingerencji w otoczenie. Nic więc dziwnego, że są coraz częściej wybierane przez inwestorów podczas planowanych przez nich działań.
EN
A mathematical model of a hybrid culture system supported with a stationary layer of liquid perfluorochemical (PFC) as a source of O2 for cells which grow in the aqueous phase of culture medium has been developed and discussed. The two-substrate Monod kinetics without inhibition effects, i.e. the Tsao-Hanson equation, has been assumed to characterise the biomass growth. The Damköhler number which relates the growth rate to the mass transfer effects has been used to appraise the regime (i.e. diffusion-limited or kinetics) of the whole process. The proposed model predicted accurately previously published data on the submerged batch cultures of Nicotiana tabacum BY-2 heterotrophic cells performed in a culture system supported with a stationary layer of hydrophobic perfluorodecalin as a liquid O2 carrier. Estimated values of the parameters of the model showed that the process proceeded in the kinetics regime and the growth kinetics, not the effects of the mass transfer between aqueous phase and liquid PFC, had essential influence on the growth of biomass.
EN
Comparative statistical analysis of the infiuence of processing parameters, for electrospinning (ES) and solution blow spinning (SBS) processes, on nanofibrous poly(L-lactic acid) (PLLA) material morphology and average fiber diameter was conducted in order to identify the key processing parameter for tailoring the product properties. Further, a comparative preliminary biocompatibility evaluation was performed. Based on Design of Experiment (DOE) principles, analysis of standard effects of voltage, air pressure, solution feed rate and concentration, on nanofibers average diameter was performed with the Pareto’s charts and the best fitted surface charts. Nanofibers were analyzed by scanning electron microscopy (SEM). The preliminary biocompatibility comparative tests were performed based on SEM microphotographs of CP5 cells cultured on materials derived from ES and SBS. Polymer solution concentration was identified as the key parameter infiuencing morphology and dimensions of nanofibrous mat produced from both techniques. In both cases, when polymer concentration increases the average fiber diameter increase. The preliminary biocompatibility test suggests that nanofibers produced by ES as well as SBS are suitable as the biomedical engineering scaffold material.
9
Content available remote Hybrydowy układ hodowlany do otrzymywania implantów tkanki chrzęstnej
PL
Opracowano hybrydowy układ do hodowli przestrzennej chondrocytów linii CP5 na polilaktydowym rusztowaniu o strukturze włóknistej wykorzystujący dwie niemieszające się fazy ciekłe: perfluorodekalinę (faza perfluorowana) i pożywkę (faza wodna). Proponowane rozwiązanie bioprocesowe zapewniło odpowiednie warunki do rozwoju komórek chrząstki nie tylko na powierzchni implantu, ale także do migracji i przerastania komórkami włóknistej struktury wewnętrznej rusztowania.
EN
A hybrid culture system which utilized two immiscible liquid phases: perfluorodecalin (hydrophobic phase) and culture medium (aqueous phase) was developed as a new method of 3-D culture of CP5 chondrocytes on fibrous polylactide scaffolds. Perfluorinated compound was applied as liquid-gas carrier which enhances the mass transfer in case of supplying/removing c respiratory gases (O2 and CO2). Robust and intensive growth of chondrocytes on the surface as well as inside scaffolds were achieved.
EN
Fully synthetic, biochemically inert and water-immiscible liquid perfluorochemicals (PFCs) are recognised as flexible liquid carriers/scavengers of gaseous compounds (respiratory gases mainly, i.e. O2 and CO2) and increasingly applied in bioprocess engineering. A range of unmatched physicochemical properties of liquid PFCs, i.e. outstanding chemo- and thermostability, extremely low surface tension, simultaneous hydro- and lipophobicity, which result from carbon chain substitution with fluorine atoms (the most electronegative chemical element) and the presence of intramolecular C–F bonds (the strongest single bond known in organic chemistry) have been described in detail. Exceptional propensity to solubility of respiratory gases in liquid perfluorinated compounds has been widely discussed. Advantages and disadvantages of bioprocess applications of liquid PFCs in the form of a pure PFC as well as in an emulsified form have been pointed out. A liquid PFC-mediated mass transfer intensification in various types of microbial, plant cell and animal cell culture systems: from miniaturised microlitre-scale cultures, via biomaterial-based scaffolds containing culture systems, to litre-scale bioreactors, has been reviewed and elaborated on bearing in mind the benefits of bioprocesses.
PL
Opracowano metodę enzymatyczną pomiaru stężenia 02 w perfluorodeka- linie (PFD) poprzez wykorzystanie układu następczych reakcji katalizowanych przez oksydoreduktazy. Metodyka pozwala określić stężenie 02 w próbie PFD o objętości rzędu mikro litrów. Wyznaczono wartości objętościowych współczynników wnikania masy w fazie gazowej i ciekłej w dwufazowym układzie PFD-tlen/powietrze.
EN
An enzymatic method for the determination of 02 solubility in perfluoro- decalin (PFD) and based on the system of two reactions catalysed by oxi- doreductases was elaborated. The proposed method enables one to determine the 02 concentration in PFD microliter-scale samples. Volumetric mass transfer coefficients in gas and liquid phases for the PFD-oxygen/air two-phase system were calculated.
PL
Przedstawiono wyniki analizy statystycznej procesu wykorzystującego przemysłowe preparaty enzymatyczne Cellic® CTec2 oraz СеШс® HTec2 do hydrolizy surowca lignocelulozowego z wierzby energetycznej (Salix viminalis L.) poddanego obróbce wstępnej metodą eksplozji pary. Wykazano niewielki wpływ preparatu Cellic HTec2 na efektywność hydrolizy. Według planu Boxa-Behnkena wyznaczono optymalne wartości temperatu¬ry (43,8°C) oraz odczynu pH (5,55) układu reakcyjnego, dla których po 72 h odnotowano stopień hydrolizy równy 0,52.
EN
Statistical analysis results of hydrolysis process of energetic willow (Salix viminalis L.) lignocellulose biomass (pre-treated with steam explosion) catalyzed by industrial enzyme preparations: Cellic® CTec2 and Cellic® HTec2, have been discussed. The negligible effect of Cellic® HTec2 on the hydrolysis efficiency has been demonstrated. Based on the Box-Behnken design, the optimum values of temperature (43.8°C) and pH (5.55) for the studied reaction system have been estimated.
PL
Hydroliza stanowi kluczowy etap w procesie otrzymywania biopaliw z surowców lignocelulozowych. W pracy przedstawiono wyniki badań enzymatycznej hydrolizy surowca z wierzby energetycznej. Przed hydrolizą surowiec poddawano obróbce wstępnej fizycznej (z wykorzystaniem promieniowania jonizującego oraz metodą eksplozji pary) lub chemicznej (kwaśnej lub zasadowej). Po 72 h hydrolizy największe stężenia glukozy uzyskano w przypadku, gdy surowiec poddano obróbce z użyciem kwasu fosforowego i etanolu.
EN
Hydrolysis is one of the most important steps in the production of biofuels from lignocellulose materials. The results of enzyme catalyzed hydrolysis of lignocellulose from energy willow is presented in the paper. Before hydrolysis, lignocellulose material has been pretreated chemically or by physical methods (ionic radiation or steam explosion). The highest glucose concentration has been obtained after 72 hours in case of lignocellulose pretreated with phosphoric acid and ethanol.
PL
Porównano wzrost mysich zarodkowych komórek macierzystych w postaci kul zarodkowych w hodowli standardowej (stała powierzchnia pokryta żelatyną) oraz w układzie ciecz/ciecz (perfluorodekalina/pożywka). Wykazano, że hodowla kul zarodkowych w układzie dwóch niemieszających się faz ciekłych pozwala znacznie wydłużyć żywotność agregatów mysich komórek macierzystych oraz prawdopodobnie utrzymać je w stanie niezróżnicowanym.
EN
The growth of mouse embryonic stem cell spheres cultured in the typical (on solid surface) and in liquid/liquid systems (perfluorodecalin/medium) has been compared. It has been showed that the liquid/liquid culture system enables one to extend the viability of cultured cells and probably maintains undifferentiated state of the mouse embryonic stem cell spheres.
15
Content available remote Hodowla mikroalg w fotobioreaktorze typu air-lift driven
PL
Przeprowadzono hodowle mikroalg Scenedesmus obliąuus w warunkach nasłonecznienia panujących w Polsce (miesiące VI-X) w fotobioreaktorze typu air-lift driven (ALD) o objętości roboczej 5,6 dm3. Zbadano wzrost mikroalg w: klasycznym ALD i ALD z pompą perystaltyczną w połowie długości pętli kolektora. Najwyższą wartość właściwej szybkości wzrostu µ uzyskano w klasycznym ALD (µ = 1,64•10-2 h-1), a najwyższe stężenie biomasy w układzie o przepływie wspomaganym pompą perystaltyczną (Cx=4,4g dm-3).
EN
Results of Scenedesmus obliąuus microalgae cultures in the 5.6 dm 3 air-lift driven photobioreactor (ALD) under solar exposure (Poland; from June October) are discussed. The growth of microlagae in a typical ALD and ALD supported with peristaltic pump was analyzed. The highest value of the specific growth rate (µ = 1.64•10-2 hr-1) was reached for the typical AL system. The highest value of the biomass concentration (Cx=4,4g dm-3) was noted for the modified ALD system.
EN
The aim of this work was to study BHK-21 fibroblasts cultured on the interfacial area of two immiscible liquids: perfluorodecalin (hydrophobic; PFD) and cell culture medium (aqueous; DMEM) what allows creating 3-D multicellular structures. We showed that the robust growth of 3-D aggregated animal cells could be achieved on flexible PFD/DMEM interfacial area. We also indicated that 3-D aggregates of BHK-21 cells could be successfully subcultured on solid hydrophobic surface and cells could migrate from those multicellular structures, spread on solid surface and further grow in typical monolayered form. Results of our experiments showed that the PFD/medium system is simple and ready-to-use method without need of any inserts traditionally used for 3-D cultures of animal cells. Formed multicellular 3-D aggregates could be directly used in the same culture system for inoculation of biomaterial elements or scaffolds.
EN
Kinetic resolution of (R)- and (S)-mandelic acid by its transesterification with vinyl acetate catalysed by Burholderia cepacia lipase has been studied. The influence of the initial substrate concentration on the kinetics of process has been investigated. A modified ping-pong bi-bi model of enzymatic transesterification of (S)-mandelic acid including substrate inhibition has been developed. The values of kinetic parameters of the model have been estimated. We have shown that the inhibition effect revealed over a certain threshold limit value of the initial concentration of substrate.
EN
The aim of this study was to determine the solubility of CO2 in perfluorodecalin (PFD) which is frequently used as efficient liquid carrier of respiratory gases in bioprocess engineering. The application of perfluorinated liquid in a microsystem has been presented. Gas-liquid mass transfer during Taylor (slug) flow in a microchannel of circular cross section 0.4 mm in diameter has been investigated. A physicochemical system of the absorption of CO2 from the CO2/N2 mixture in perfluorodecalin has been applied. The Henry’s law constants have been found according to two theoretical approaches: physical (H = 1.22x10-3 mol/m3Pa) or chemical (H = 1.26x10-3 mol/m3Pa) absorption. We are hypothesising that the gas-liquid microchannel system is applicable to determine the solubility of respiratory gases in perfluorinated liquids.
EN
The aim of this paper is to present the implementation of the method for solving linear interval equations using the "interval extended zero" method and multimedia extensions. The "interval extended zero" method allows us to reduce the undesirable excess width effect. Its efficiency was proven before and here we show that it can be used to perform fast calculations using multimedia extensions. Some numerical examples are used to illustrate the efficiency of our implementation in comparison with several numerical libraries for interval arithmetic.
PL
Otrzymane wyniki badań potwierdzają, że zastosowanie rozszerzeń multimedialnych SSE w zagadnieniach związanych z arytmetyka˛ przedziałową znacznie skraca czas wykonywania obliczeń. Biblioteki Profil/BIAS oraz Boost, które zostały zaimplementowane z pominięciem rozszerzeń multimedialnych wykonują. obliczenia zdecydowanie dłużej. Zastosowanie innego formatu przechowywania przedziałów w pamięci ([a --- a]) oraz odpowiednie zmodyfikowanie operacji arytmetycznych pozwoliło na wykonywanie obliczeń bez ciągłej zmiany trybu zaokrąglania, co nie spowodowało utraty wydajności. Ponadto zastosowana w naszej implementacji zmodyfikowana metoda dzielenia bazująca na koncepcji metody "rozszerzonego przedziałowego zero" pozwala na uzyskiwanie znacznie węższych przedziałów, bez utraty wydajności.
EN
The aim of this paper is to show interval arithmetics implementation using single-instructionmultiple- data (SIMD) SSE (Streaming SIMD Extensions) multimedia instructions, and register set extensions. It was proven previously that SSE extensions can increase performance of interval calculations, since both interval bounds can be kept in one SSE register and all arithmetic operations can be done in parallel. In this work a new approach to the modified interval division is proposed based on the concept of “interval extended zero” method which is a part of this implementation. This method allows us to reduce the undesirable excess width effect. We show the results obtained for several randomly generated matrices using different algorithms (matrix-matrix multiplication, Gauss elimination) and compare them also with results obtained using other interval libraries.
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