Smallanthus sonchifolius is an Asteraceae native from the Andes Mountains that accumulates inulin-type fructans in the underground reserve organs, the tuberous roots and the rhizophores. Yellow callus was obtained from tuberous roots, giving origin, spontaneously to red callus. Fructans and their metabolizing enzymes were analyzed in calli of both types, showing similar fructan contents in both lineages. However, synthesizing activity was higher in red callus, while hydrolyzing activity was higher in yellow callus. HPAEC/ PAD analyses revealed the presence of fructo-oligosaccharides in both calli with degrees of polymerization lower than those found in plants cultured ex vitro, indicating that this characteristic was maintained in undifferentiated cells. The presence of fructans and the differences between the activities of fructosyltransferases and hydrolases found in red and yellow calli indicate this material as suitable for studies of fructan metabolism under controlled conditions.
fructan; in vitro conditions; inulin; yacon
