Digitalis lanata, biotransformation

Digitalis lanata Ehrh. (Scrophulariaceae), a biennial plant, is pharmaceutically important as a source of the cardenolides digoxin, lanatoside C, and deslanoside, which are commonly used in the treatment of heart diseases [4]. Tissue cultures of this plant have been investigated by many researchers [104, 105] for clonal propagation [106, 107] and the production [108, 109, 110 111] and biotransformation of cardenolides [112, 113, 114, 115]. 

Another use of IPCs involves one or two step biotransformations such as hydroxylations, glycosylations, acetylations and methylations. The most detailed work in this area has been on the hydroxylation of cardiac glycosides of Digitalis lanata and the formation of indole akaloids in Catharanthus roseus. 

In the meantime, we expect plant cell culture experimentation to be continued even though the initial promise has not yet been fulfilled. More important than the production of compounds may be the use of cultures in biotransformation reactions. The cells may elaborate enzymes that can cause an organic reaction to take place that could be next to impossible to carry out synthetically. An example of this is the 2-p hydroxylation of digitoxin to digoxin by cell lines of Digitalis lanata. Thus, cells from certain woody species might be put to work as part of an overall synthesis of valuable pharmaceuticals. For this to happen, much more work is needed on biotransformations taking place within woody plants. 

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