Abstract:
: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. (c) 1994 John Wiley & Sons, Inc.
journal_name
Biotechnol Bioengjournal_title
Biotechnology and bioengineeringauthors
Schlatmann JE,Moreno PR,Vinke JL,Ten Hoopen HJ,Verpoorte R,Heijnen JJdoi
10.1002/bit.260440409subject
Has Abstractpub_date
1994-08-05 00:00:00pages
461-8issue
4eissn
0006-3592issn
1097-0290journal_volume
44pub_type
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