Search results for "Suspension culture"
showing 9 items of 9 documents
High-Yield Formation of Arbutin from Hydroquinone by Cell-Suspension Cultures ofRauwolfia serpentina
1992
High-density cell-suspension cultures of Rauwolfia serpentina cultivated in a nutrition medium optimized for the production of the glucoalkaloid raucaffricine synthesize hydroquinone glycosides from continuously added hydroquinone with a total yield of 23.87 g/1 (18 g/1 of arbutin and 5.87 g/1 of a hydroquinone diglycoside) in 7 days. This arbutin production is by far the highest formation of a natural product by plant-cell-culture systems reported to date.
Inverse correlated 1H-13C in vivo NMR as a probe to follow the metabolism of unlabeled vanillin by plant cell cultures
1997
Abstract Inverse correlated 2D 1H-13C NMR spectroscopy was used to follow the metabolism of vanillin (1) in vivo by plant cell suspension cultures of Nicotiana plumbaginifolia at the natural abundance of 13C. Under the non-invasive conditions four products could be detected: vanillylalcohol (2), vanillinglucoside (3) and the phenolic and benzylic glucosides of vanillylalcohol (4 and 5).
Enzymatic Formation of Raucaffricine, the Major Indole Alkaloid ofRauwolfia serpentinaCell-Suspension Cultures
1991
The major alkaloid from Rauwolfia serpentina cell-suspension cultures, the glucoalkaloid raucaffricine (2), was enzymatically formed from vomilenine (1) and UDPG in presence of microsomal-bound enzyme. This glucosyltransferase exhibits a relatively high substrate specificity with strong preference for 1 and UDPG. The apparent Km values for 1 and UDPG were 40 μM and 0.8 mM, respectively, for raucaffricine formation. Optimum transferase activity was observed at 50° and pH 6.3. The taxonomic distribution of this enzyme seems to be very limited because transferase can he exclusively detected in raucaffricine-producing plant cells.
Rice protoplasts isolated directly from mature-embryo-derived calli
1996
Mature-embryo-derived calli of japonica rice (Oryza sativa L) Taipei 309 were used for replicated protoplast isolation experiments. Six out of nine callus lines produced protoplasts with satisfactory yield of 5.20×106–8.96×106 protoplasts/g FW (fresh weight). The remaining three callus lines initiated from seeds of cryopreserved-callus-derived plants had rooty calli, resulting in low yield of protoplasts and a large number of isolated banana-shape intact cells. Viability of protoplasts ranged 87.46%–94.15%. The average size of protoplasts was 207.49–379.04 μm2 in different callus lines. Comparitive experiments were also carried out using both calli and suspension culture cells for protoplas…
Novel indole alkaloids from cell suspension cultures of aspidosperma quebracho blanco schlecht
1991
Abstract Two novel monoterpenoid indole alkaloids, aspidochibine ( 1 ) and 3-oxo-14,15-dehydrorhazinilam ( 2 ), were isolated from cell suspension cultures of Aspidosperma quebracho blanco Schlecht. Aspidochibine ( 1 ) exhibits a new alkaloid skeleton. The structure of these alkaloids was elucidated by spectroscopic methods.
Chapter 2 Biosynthesis in Rauwolfia serpentina Modern Aspects of an Old Medicinal Plant
1995
Publisher Summary This chapter discusses a research on Rauwolfia , which was achieved after the generation of a cell suspension with extraordinary growth characteristics and physiological behavior. The investigations demonstrated that a range of techniques is now available for the clarification of complete metabolic pathways, provided that the appropriate efficient biological system is available. The isolation and identification of each single enzyme have almost become routine, even if an extremely sensitive protein analytic technique is necessary when several kilograms of fresh plant cells are reduced to a few micrograms of homogenous protein. The successful identification of a total of 20…
A versatile bioreactor for dynamic suspension cell culture. Application to the culture of cancer cell spheroids.
2016
A versatile bioreactor suitable for dynamic suspension cell culture under tunable shear stress conditions has been developed and preliminarily tested culturing cancer cell spheroids. By adopting simple technological solutions and avoiding rotating components, the bioreactor exploits the laminar hydrodynamics establishing within the culture chamber enabling dynamic cell suspension in an environment favourable to mass transport, under a wide range of tunable shear stress conditions. The design phase of the device has been supported by multiphysics modelling and has provided a comprehensive analysis of the operating principles of the bioreactor. Moreover, an explanatory example is herein prese…