Library

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
    The negligible role of carbon dioxide and ethylene in ajmalicine production by Catharanthus roseus cell suspensions (1994)
    Springer
    Plant cell reports 14 (1994), S. 157-160 
    Details
    ISSN: 1432-203X
    Keywords: Ajmalicine ; Carbon dioxide ; Ethylene ; Bioreactor ; Catharanthus roseus
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Removal of gaseous metabolites in an aerated fermenter affects ajmalicine production by Catharanthus roseus negatively. Therefore, the role of CO2 and ethylene in ajmalicine production by C. roseus was investigated in 3 l fermenters (working volume 1.8 l) with recirculation of a large part of the exhaust air. Removal of CO2, ethylene or both from the recirculation stream did not have an effect on ajmalicine production. Inhibition of ethylene biosynthesis in shake flasks with Co2+, Ni2+ or aminooxyacetic acid did not affect ajmalicine production. However, the removal of CO2 did enhance the amount of extracellular ajmalicine.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00233781
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Ajmalicine production by cell cultures of Catharanthus roseus: from shake flask to bioreactor (1994)
    Springer
    Plant cell, tissue and organ culture 38 (1994), S. 85-91 
    Details
    ISSN: 1573-5044
    Keywords: Ajmalicine ; bioreactor ; Catharanthus roseus ; growth model ; scale-up
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The productivity of a cell culture for the production of a secondary metabolite is defined by three factors: specific growth rate, specific product formation rate, and biomass concentration during production. The effect of scaling-up from shake flask to bioreactor on growth and production and the effect of increasing the biomass concentration were investigated for the production of ajmalicine by Catharanthus roseus cell suspensions. Growth of biomass was not affected by the type of culture vessel. Growth, carbohydrate storage, glucose and oxygen consumption, and the carbon dioxide production could be predicted rather well by a structured model with the internal phosphate and the external glucose concentration as the controlling factors. The production of ajmalicine on production medium in a shake flask was not reproduced in a bioreactor. The production could be restored by creating a gas regime in the bioreactor comparable to that in a shake flask. Increasing the biomass concentration both in a shake flask and in a stirred fermenter decreased the ajmalicine production rate. This effect could be removed partly by controlling the oxygen concentration in the more dense culture at 85% air saturation.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00033865
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Kinetics and stoichiometry of growth of plant cell cultures of Catharanthus roseus and Nicotiana tabacum in batch and continuous fermentors (1992)
    New York, NY [u.a.] : Wiley-Blackwell
    Biotechnology and Bioengineering 40 (1992), S. 863-874 
    Details
    ISSN: 0006-3592
    Keywords: plant cell suspension cultures ; chemostat culture ; growth kinetics ; stoichiometry ; Catharanthus roseus ; Nicotiana tabacum ; Chemistry ; Biochemistry and Biotechnology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Plant cell suspension cultures of Catharanthus roseus and Nicotiana tabacum were grown in stirred tank bioreactors operated in batch and continuous mode. The stoichiometry of growth of both species in steady-state glucose limited chemostats was studied at a range of different dilution rates. A linear relation was applied to describe specific glucose uptake, oxygen consumption, and carbon dioxide production as a function of the growth rate. Specific respiration deviated greatly from the linear relation. An unstructured mathematical model, based on the observed stoichiometry in the glucose limited chemostats, was applied to describe the growth in batch culture. From a comparison between the observed growth pattern in batch fermentors and computer simulations it appeared that the stoichiometry of growth of the C. roseus culture was different under steady-state and dynamic conditions. It was concluded that a mathematical model for the growth of suspension culture plant cells in which the biomass is considered to be a single compound with an average chemical composition is of limited value because large changes in the conmposition of the biomass may occur. © 1992 John Wiley & Sons, Inc.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/bit.260400802
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Two-stage batch process for the production of ajmalicine by Catharanthus roseus: The link between growth and production stage (1995)
    New York, NY [u.a.] : Wiley-Blackwell
    Biotechnology and Bioengineering 47 (1995), S. 53-59 
    Details
    ISSN: 0006-3592
    Keywords: ajmalicine ; Catharanthus roseus ; alkaloid formation ; Chemistry ; Biochemistry and Biotechnology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: The link between the growth stage and the production stage in a two-stage batch process was investigated using (filtered) inocula from different periods of the stationary phase of the growth cycle. In the production stage, ajmalicine production by Catharanthus roseus in a 3-L stirred tank reactor was induced with a high glucose concentration (80 g/L). Ajmalicine production in cultures started with cells from the late stationary phase was five times higher than in cultures started with cells from the early stationary phase. After transfer to the production stage, cells from the early stationary phase showed a transient increase in respiration and enzyme induction, followed by culture browning. In contrast, cells in the late stationary phase showed a typical induction pattern: constant respiration, and permanent enzyme induction. A striking similarity between the geraniol-10-hydroxylase (G10H) activity and the ajmalicine accumulation profile could be observed in all cultures, suggesting that G 10H regulated ajmalicine production in this investigation. The intracellular nitrate concentration was significantly higher in the inoculum showing a high ajmalicine production than in the inoculum with a low production. Consequently, nitrate may act as a marker for the start of the production stage: as soon as the nitrate is depleted in the growth medium secondary metabolism can be induced. © 1995 John Wiley & Sons, Inc.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/bit.260470107
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    A structured model describing carbon and phosphate limited growth of Catharanthus roseus plant cell suspensions in batch and chemostat culture (1993)
    New York, NY [u.a.] : Wiley-Blackwell
    Biotechnology and Bioengineering 41 (1993), S. 771-780 
    Details
    ISSN: 0006-3592
    Keywords: Catharanthus roseus ; glucose limitation ; growth kinetics ; phosphate limitation ; plant cell suspension culture ; structured growth model ; Chemistry ; Biochemistry and Biotechnology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: The growth of plant cell suspension cultures of Catharanthus roseus in batch fermentors was studied at different initial phosphate levels of the medium. On the basis of the observations and existing knowledge with respect to phosphate metabolism in cultured C. roseus cells, a structured mathematical model was developed for the description of the kinetics of growth and intracellular accumulation of glucose and phosphate, as a function of glucose and phosphate supply. It was shown that the model offers not only good description of the growth of the cells in batch culture at different initial phosphate levels, but also provided a satisfactory description of the growth in glucose limited chemostats. © 1993 Wiley & Sons, Inc.
    Additional Material: 9 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/bit.260410803
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Relation between dissolved oxygen concentration and ajmalicine production rate in high-density cultures of Catharanthus roseus (1995)
    New York, NY [u.a.] : Wiley-Blackwell
    Biotechnology and Bioengineering 45 (1995), S. 435-439 
    Details
    ISSN: 0006-3592
    Keywords: Catharanthus roseus ; ajmalicine production rate ; dissolved oxygen concentration ; kinetic model ; high-density culture ; Chemistry ; Biochemistry and Biotechnology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: The relation between dissolved oxygen (DO) and the ajmalicine production rate of Catharanthus roseus was investigated in 15-L tank reactors at constant stirrer speed and gas flow rate. Below a DO concentration of 29% of air saturation the ajmalicine production rate was less than 0.06 μmol/g/d. Above a DO of 43% the ajmalicine production rate was constant at 0.21 μmol/g/d. Between a DO of 29% and 43% there was a strong relation between the ajmalicine production rate and the DO concentration. After a period of at least 12 days at DO ≤29% the culture lacked the ability to adapt to a DO ≥57%. A kinetic equation is proposed for the relation between DO and the specific ajmalicine production rate. © 1995 John Wiley & Sons, Inc.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/bit.260450508
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Effects of oxygen and nutrients limitation on ajmalicine production and related enzyme activities in high density cultures of Catharanthus roseus (1994)
    New York, NY [u.a.] : Wiley-Blackwell
    Biotechnology and Bioengineering 44 (1994), S. 461-468 
    Details
    ISSN: 0006-3592
    Keywords: Catharanthus roseus ; ajmalicine production ; enzyme activities ; dissolved oxygen ; nutrients concentration ; high density culture ; Chemistry ; Biochemistry and Biotechnology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Oxygen and nutrient limitation was investigated in order to identify the origin of a lower specific ajmalicine production in Catharanthus roseus cultures at high cell densities in an induction medium. The effect of oxygen limitation was explored by comparing two identically aerated and agitated high cell density bioreactor cultures with dissolved oxygen (DO) concentration of 15% and 85% of air saturation, with respect to alkaloid formation and related enzymes activities. Oxygen had an evident effect on ajmalicine production: in the high DO cultures production was more than 5 times higher than in the low DO cultures. The difference in ajmalicine production between high and low DO could not be explained by the enzyme activity profiles. Moreover, the productivity in the high density culture could not restored to the level of a low density culture (at a high DO) by increasing the DO alone. The effect of nutrient limitation was studied with response surface methodology in shake flask cultures. Nutrient limitation could not be demonstrated to be responsible for the productivity loss. Alkaloid and enzyme measurements in the shake flask cultures supported previous findings that the tryptamine pathway may regulate alkaloid production, provided that the terpenoid pathway is sufficiently active. © 1994 John Wiley & Sons, Inc.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/bit.260440409
    Library Location Call Number Volume/Issue/Year 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...