3.3 Biosynthesis of Steroid Glycosides
Biotransformation of steroids
and cardiac glycosides (e.g., gitoxin, digitoxin) by plant
cell cultures have been studied extensively and have been reviewed by Reinhard*
(1974), Stohs and Rosenberg** (1975), Stohs*** (1977), and Furuya**** (1978).
However, in general the steroidal
aglycones of cardioactive glycosides may be assumed to have formed
as a broad based overall mechanism of steroid biogenesis as shown below:
Acetate -> Mevalonate -> Isopentenyl
Pyrophosphate -> Squalene æÆSteroid
The steroidal molecule is
considered to have generated with the head to tail linkage of several acetate
units.
___________________________________________
*
Reinhard, E., In Tissue Culture and Plant Science—1974,
(H.E. Street Ed.), Academic Press, New York, pp.
433-459,
1974.
**
Stohs S.J., and H. Rosenburg., Lloydia,
38, 181-194, 1975.
***
Stohs, S.J., ‘In plant Tissue Culture and its
Biotechnological Applications’, (W. Barz, E.
Reinhard and M.H.
Zenk,
eds), Springer-Verlag, New York, pp. 142-150, 1977.
****
Fuarya, T., In ‘Frontiers of Plant Tissue Culture’,
(T.a. Thorpe-ed.) The Boostore, University of Calgary, Alberta,
Canada,
pp. 191-200, 1978.
Source:Pharmacognosy And Pharmacobiotechnology By Ashutosh Kar
Source:Pharmacognosy And Pharmacobiotechnology By Ashutosh Kar
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