Popis: |
The metabolic relationship between littorine and hyoscyamine has been monitored in transformed roots of Datura stramonium. Quantification by GC of unlabelled littorine and by GCMS of 13C-labelled littorine demonstrated that exogenously added littorine (0.1 mM) was significantly metabolised (35%) to hyoscyamine. In contrast, exogenously added hyoscyamine was not metabolised to littorine, indicating that this conversion is irreversible. The conversion of littorine to hyoscyamine was suppressed by P-450 oxidase inhibitors (particularly clotrimazole), implicating the involvement, at least in part of a cytochrome P-450 activity operating hyoscyamine biosynthesis. |