Cryopreservation of hairy root cultures from Maesa lanceolata.

Maesa lanceolata is a medicinal plant, growing in the tropics of Africa and Asia. It produces a mixture of triterpenoid saponins, some of which have medicinal properties that are of commercial interest. For instance, saponins isolated from Maesa lanceolata exert antiviral, haemolytic and antiangiogenic activities [1]. As conventional plant growth and production is not very well controlled, in vitro propagation was explored as an alternative for rapid multiplication. A fast and reliable reproduction of the species was achieved through the development of an axillary shoot formation [2]. To evaluate the production of saponins in Maesa lanceolata grown under in vitro conditions, hairy roots were established by infecting leaf discs with Agrobacterium rhizogenes. In vitro culture of hairy roots is, however, labor intensive and expensive, and there is a risk of contamination and genetic changes. Because of this we are currently developing a protocol for cryopreservation of root tips. Two methods, vitrification and encapsulationdehydration, are being tested.