GLORIA

GEOMAR Library Ocean Research Information Access

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    Kinetics of microbial oxidation of n-heptane. I. Characterization of the process (1969)
    New York, NY [u.a.] : Wiley-Blackwell
    Biotechnology and Bioengineering 11 (1969), S. 417-426 
    Details
    ISSN: 0006-3592
    Keywords: Chemistry ; Biochemistry and Biotechnology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Utilization of n-heptane by a Pseudomonad was studied in pilot-size butch cultures. Optimal pH and temperature were determined by a factorial design and a medium based upon mineral uptake rates was formulated. High cell yields were obtained by volatilizing heptane in the incoming air and thereby achieving good hydrocarbon dispersion. Hydrocarbon carried by effluent gases was recovered and recycled. In cultures where pH is not controlled, decrease in the electrolytic conductivity of the medium was found to be indicative of viable cells and was used in monitoring bacterial propagation. If not checked, increase in salinity in pH controlled cultures was found to affect cell production negatively. Viscosity changes were not very significant. Heptane to aqueous medium ratio was found to affect oxygen supply to the system due to higher dissolved oxygen concentrations associated with hydrocarbons.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/bit.260110313
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    The effects of surface adsorption on the thermal stability of proteins (1992)
    New York, NY [u.a.] : Wiley-Blackwell
    Biotechnology and Bioengineering 40 (1992), S. 8-15 
    Details
    ISSN: 0006-3592
    Keywords: adsorption ; silica ; proteins ; lysozyme ; surface polarity ; protein stability ; Chemistry ; Biochemistry and Biotechnology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: The effect of surface adsorption on the structure and stability of proteins is a matter of increasing interest in biotechnology. Therefore, we have examined the effect of adsorption to silica on the thermal stability of 7 proteins employing differential scanning calorimetry (DSC) and front surface fluorescence (FSF) spectroscopy. In general, it was found that surface adsorption decreased the thermal stability of the bound protein. Using lysozyme for further studies, DSC, FSF, and FTIR spectroscopies, as well as enzymatic activity measurements, were used to explore the effect of decreasing surface apolarity on stability. It was observed that increasing surface apolarity produced decreasing stability and increasing structural alteration of the adsorbed protein.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/bit.260400103
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Effect of feed zone in fed-batch fermentations of Saccharomyces cerevisiae (1992)
    New York, NY [u.a.] : Wiley-Blackwell
    Biotechnology and Bioengineering 40 (1992), S. 235-246 
    Details
    ISSN: 0006-3592
    Keywords: Fed-batch fermentation ; concentration fluctuations ; mixing effects ; Saccharomyces cerevisiae ; circulation time distribution ; Chemistry ; Biochemistry and Biotechnology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: In production-scale, fed-batch fermentations, feed is often added to a single point at the top of the fermentor, which, combined with poor mixing, results in formation of a “feed zone” rich in nutrients. Frequent exposure of the culture to high concentrations of nutrients in the feed zone for sufficient duration can produce unexpected effects on its performance. The effect of the feed zone was evaluated by conducting aerobic fed-batch fermentations of Saccharomyces cerevisiae with both complex and defined media. The broth was recirculated between a recycle loop and a bench-scale fermentor, and feed was intermittently added into the recycle loop to simulate the circulation of cells through the feed zone. Experiments were carried out for a range of residence times in the recycle loop from 0.5 to 12 min. Biomass yields from the complex-media fermentations were not affected by exposure to high nutrient levels in the recycle loop for residence times up to 12 min. Ethanol consumption was reduced by as much as 50% for residence time in the loop up to 3 min. Very long exposure of yeast cells to excess nutrient levels (12 min) gave acetic acid formation. In a defined medium, the simulated feed zone effect increased biomass yield by up to 10%, but had no effect on ethanol levels. This study indicates that the feed zone effect on biomass yield in yeast fermentation, using complex substrates, will be negligible under fully aerobic conditions.
    Additional Material: 9 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/bit.260400207
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Shift from growth to nutrient-limited maintenance kinetics during biofilter acclimation (1997)
    New York, NY [u.a.] : Wiley-Blackwell
    Biotechnology and Bioengineering 56 (1997), S. 330-339 
    Details
    ISSN: 0006-3592
    Keywords: biofilter ; kinetics ; maintenance metabolism ; acclimation ; biomass ; nutrient limitation ; Chemistry ; Biochemistry and Biotechnology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: During long-term operation of a biofilter, the mandatory absence of net cell growth forces the cells into maintenance metabolism, which is of relatively low rate compared to substrate consumption during the active growth of the acclimation phase. A model based on this shift in metabolism can explain the postacclimation decrease in activity sometimes reported for biofilters. The cessation of growth can be caused by nutrient depletion in the bed. Postacclimation nutrient addition increases activity primarily by allowing a return to the high substrate consumption rate of active growth, and only secondarily helps raise bed activity because of the ultimately higher amount of biomass in the bed. Simulations incorporating the acclimation period and the role of maintenance metabolism predict about 4 logarithms of growth during acclimation of a hexane biofilter, which was confirmed experimentally. Changes in a biofilter's biomass during the acclimation phase can be estimated from substrate conversion data using two approximate methods. The first follows the cumulative amount of substrate converted and uses the estimated yield of cells from substrate during active growth to estimate the total biomass created. The second method follows a rate constant for conversion of substrate in the bed. © 1997 John Wiley & Sons, Inc. Biotechnol Bioeng 56: 330-339, 1997.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
  • 5
    Electronic Resource
    Electronic Resource
    Physical modeling of animal cell damage by hydrodynamic forces in suspension cultures (1992)
    New York, NY [u.a.] : Wiley-Blackwell
    Biotechnology and Bioengineering 40 (1992), S. 1277-1281 
    Details
    ISSN: 0006-3592
    Keywords: microcapsule ; physical model ; animal cell ; suspension culutre ; hydrodynamic force ; damage ; Chemistry ; Biochemistry and Biotechnology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Physical damage of animal cells in suspension culture, due to stirring and sparging, is coupled with complex metabolic responses. Nylon microcapsules, therefore, were used as a physical model to study the mechanisms of damage in a stirred bioreactor and in a bubble column. Microcapsule breaskage folowed first-order kinetices in all experiments Entrainment of bubbles into the liquid phase in the stirred bioreactor gave more microcapsule breakage. In the bubble column, the bubble bursting zone at gas-liquid interface was primarilu responsible for microcapsule breakage. The forces on the microcapsules were equivalent to an external pressure of approximately 4 × 104 N · m-2, based on the critical microcapsule diameter for survival of 190 μm. A stable foam layer, however, was found to be effective in protecting microcapsules from damage. The microcapsule transport to the gas-liquid interface and entrainment into the foam phase was consistent with flotation by air bubbles. This result implies that additives and operation of bioreactors should be selected to minimize flotation of cells. © 1992 John Wiley & Sons, Inc.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/bit.260401018
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Experimental simulation of dissolved oxygen fluctuations in large fermentors: Effect on Streptomyces clavuligerus (1991)
    New York, NY [u.a.] : Wiley-Blackwell
    Biotechnology and Bioengineering 38 (1991), S. 1203-1209 
    Details
    ISSN: 0006-3592
    Keywords: oxygen fluctuations ; cephamycin C ; antibiotics ; Chemistry ; Biochemistry and Biotechnology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: An experimental Monte Carlo method was used to study the effect of fluctuations in oxygen concentration on the synthesis of antibiotics by Streptomyces clavuligerus. Air was supplied to the culture in a 2-L fermentor in random cycles following the lognormal distribution in order to model the circulation within large production-scale vessels. Each cycle consisted of air supply for 5 s followed by no aeration for the balance of the cycle time which ranged from 8 to 44 s, with a mean time of 20 s. Comparable experiments were also conducted with constant period cycling of air and with continuous supply of air. The yields of cephamycin C and its precursor, penicillin N, were suppressed by the Monte Carlo simulation of circulation in a large tank, as compared to constant period cycling. The concentration of dissolved oxygen remained at a low, ca. 5% of saturation, for 5-10 h longer during the Monte Carlo experiment than during the periodic aeration experiment. The biosynthetic enzymes, which are sensitive to oxygen levels, were likely affected not only by the mean time of cycling but also by the distribution of the cycles.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/bit.260381012
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Effect of oxygen fluctuations on recombinant Escherichia coli fermentation (1993)
    New York, NY [u.a.] : Wiley-Blackwell
    Biotechnology and Bioengineering 41 (1993), S. 666-670 
    Details
    ISSN: 0006-3592
    Keywords: oxygen fluctuations ; plasmid amplification ; Escherichia coli ; circulation time distribution ; Chemistry ; Biochemistry and Biotechnology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Escherichia coli DH5α, carrying the pUC19 plasmid for the lacZ fragment of β-galactosidase and ampicillin resistance, was grown in a batch fermentor under conditions of fluctuating oxygen supply. A Monte Carlo method was used to control the on/off supply of air to simulate circulation of cells in a large fermentor. Rapid changes in oxygen supply reduced the rates of oxygen uptake the carbon dioxide release and prolonged the active second growth phase in batch culture, compared to growth with continuous aeration. Amplification of the plasmid was observed during the stationary phase when air supplied continuously, but not during the Monte Carlo experiments. © 1993 John Wiley & Sons, Inc.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/bit.260410610
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    Cultivation of hybridoma cells in an inclined bioreactor (1995)
    New York, NY [u.a.] : Wiley-Blackwell
    Biotechnology and Bioengineering 45 (1995), S. 176-186 
    Details
    ISSN: 0006-3592
    Keywords: animal cell ; hybridoma cell ; shear ; cell damage ; bioreactor design ; inclination ; bubble column ; Chemistry ; Biochemistry and Biotechnology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Murine hybridoma cells were grown in a bubble column that was inclined up to 45° from vertical. Inclining the column by a few degrees separated the rising bubbles against the upper surface, leaving the bulk of the liquid bubble free. The liquid was circulated well by the rising bubbles, but collection of cells by rising bubbles and exposure of cells to bursting bubbles were minimized. Maximum viable cell count and exponential growth of the cells were not affected by inclination, but an inclination of 30° gave an antibody titer of 42 mg/L, which more than doubled the yield of 17 mg/L in the vertical position. By comparison, the culture gave yields of 30 mg/L when grown in spinner flasks. The enhanced antibody production in the inclined bioreactor corresponded to a prolonged stationary phase of 45 h. © 1995 John Wiley & Sons, Inc.
    Additional Material: 11 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/bit.260450212
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    In vitro degradation of natural insoluble lignin in aqueous media by the extracellular peroxidases of Phanerochaete chrysosporium (1998)
    New York, NY [u.a.] : Wiley-Blackwell
    Biotechnology and Bioengineering 57 (1998), S. 704-717 
    Details
    ISSN: 0006-3592
    Keywords: lignin peroxidase ; manganese peroxidase ; LIP ; MNP ; Phanerochaete chrysosporium ; Chemistry ; Biochemistry and Biotechnology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: The lignin peroxidases (LIP) and manganese peroxidases (MNP) of Phanerochaete chrysosporium catalyze a wide range of lignin depolymerization reactions with lignin models and synthetic lignins in solution. However, their ability to degrade insoluble natural lignin in aqueous media has not been demonstrated. Insoluble isolated poplar lignin similar to natural lignin was treated in vitro in aqueous media for 12 h with LIP, MNP, and both. Treatment with MNP alone slightly increased the solid mass and produced measurable amounts of lignin-derived 2,6-dimethoxyhydroquinone and 2-methoxyhydroquinone but did not appreciably decrease the total lignin content. Treatment with LIP alone did not decrease the mass but produced measurable amounts of lignin-derived p-hydroxybenzoic acid and slightly decreased the lignin content. Finally, treatment with LIP and MNP together decreased the solid mass by 11%, decreased the lignin content by 5%, and released low-concentration compounds with mass spectra containing the typical lignin-derived electron-impact fragments of mass 107, 137, 151, 167, and 181. These results suggest that MNP increases the effectiveness of LIP-mediated lignin degradation. © 1998 John Wiley & Sons, Inc. Biotechnol Bioeng 57: 704-717, 1998
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
  • 10
    Electronic Resource
    Electronic Resource
    Microbial growth on hydrocarbons - some experimental results (1975)
    New York, NY [u.a.] : Wiley-Blackwell
    Biotechnology and Bioengineering 17 (1975), S. 241-251 
    Details
    ISSN: 0006-3592
    Keywords: Chemistry ; Biochemistry and Biotechnology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: A simple mechanism of hydrocarbon uptake by microorganisms is examined. This model considers the presence of micelles of surface active agents as essential for growth of microbial cells on hydrocarbon substrates. Larger hydrocarbon droplets serving as reservoirs may also be present. Experimental results to support the model are presented. The results of others are explained on the basis of this model.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/bit.260170209
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...