Artificial near-ultraviolet light with a peak at 370 nm and the light of natural radiation
with wavelengths between 290 and 380 nm stimulated the synthesis of dimeric indole
alkaloids in intact plants of Catharanthus roseus. The artificial light also specifically stimulated an in vitro FMN-mediated, non-enzymatic coupling of vindoline and catharanthine to synthesize
an iminium intermediate, the in vivo precursor of dimeric alkaloid synthesis. These results suggest that near-ultraviolet
light is necessary for catharanthine oxidation as a trigger reaction of dimer synthesis
in the plants.
Catharanthus roseus
- dimeric indole alkaloid synthesis - vindoline - catharanthine - UV irradiation -
3′,4′-anhydrovinblastine
