Gentiana punctata L. is a rare and endangered species, which has become nearly extinct due to the uncontrolled harvesting of rhizomes, which are rich in bitter glycosides. We consider that transgenic root culture production in bioreactors could be an alternative mean for the production of secondary metabolites of G. punctata.

Transgenig roots were induced with A. tumefaciens C58C1 (pArA4b) and A. rhizogenes A4M70GUS. Both clones were maintained continuously during the last ten years on liquid and agar solidified medium. Biomass production was several times higher on liquid medium in both clones whilst the production of bitter compounds was roughly the same. Comparison of two clones showed that the fresh weight increase of the C58C1 clone was much higher (12.4 x) in comparison to the slower growing A4M70GUS clone (2.5 x).

Extraction of secoiridoid glucosides was performed with MeOH and analysis by TLC and HPLC. In both clones only gentiopicrin was detected. Concentrations were 0.26-0.33% in C58C1 clone and 0.57-0.67% in the A4M70GUS clone. Although gentopicrin concentration in A4M70GUS clone roots was higher the total gentiopicrin production of the C58C1 clone was higher due to its high biomass increase.