Intra and extra-cellular accumulation of three alkaloid markers, the disappearance of major nutrients from the medium and the evolution of phosphates, nitrates, ammonium ions, glucose and starch in the cells were observed during a time course study using a suspension of Catharanthus roseus. The accumulation of alkaloids is a complex phenomenon, not entirely unconnected with growth, which involves diffusion into the medium and cellular catabolism. It is difficult to relate the phenomenon to the appearance of disappearance of any one metabolite in particular.