[Investigations on harpagophytum.].

Comparing the analytical results of the constituants of naturally growing roots and callus of Harpagophytum procumbens, it could be demonstrated that both, the products of the primary and the secondary metabolism, showed important differences. Harpagosid which is present in significant amounts in the roots and tubers of the fresh plants, was shown to be completely absent in the callus. Stachyose the main reserve carbohydrate again was only produced in minor amounts. Fructose was the predominant sugar in the callus cells.