Terpenoid indole alkaloid profile changes in Catharanthus pusillus during development.

The terpenoid indole alkaloid content of Catharanthus pusillus was investigated during development from young to old plants. Different plant organs were assessed showing that the new leaves were the main repository site with vindoline ( approximately 4.8 mg/g DW) and catharanthine ( approximately 2.2 mg/g DW) being the major metabolites with the highest yields at the second and third sampling time (51 and 70 days, respectively). The other samples analysed, from old, oldest and yellow leaves followed in accumulation levels. The roots and stems were the least accumulative organs, although for the case of tubotaiwine the root was the most important organ. It appeared that the alkaloid content changed coinciding with the different developmental stages of the plants, particularly at flowering and fruiting stages. Moreover, this species seems to constitute a precious source of the monomerics, vindoline and catharanthine, intermediates in the synthesis of the two important antitumor dimerics vincristine and vinblastine, which did not accumulate in this species.