PRODUCTION OF VALEPOTRIATES BY HAIRY ROOT CULTURES OF CENTRANTHUS-RUBER DC

Hairy root cultures of Centranthus ruber DC. were established by infec tion of sterile plantlets with Agrobacterium rhizogenes, strain R1601. The transformed roots were grown in 12 different, hormone-free liquid media, and valtrate, isovaltrate, 7-desisovaleroyl-7-acetylvaltrate, 7-homovaltrate, didrovaltrate and isovaleroxyhydroxydidrovaltrate were quantified by high performance liquid chromatography. The highest ove rall valepotriate content (3.0% dry wt) was observed in half-strength Gamborg B5 medium supplemented with 3% sucrose. This concentration is very similar to that found in the roots of parent plants grown in the field. The use of N,N-dimethylmorpholinium iodide, a plant bioregulato r, was very detrimental to the hairy root growth and to the valepotria te production. The hairy roots cultured in half strength Gamborg B5 li quid medium supplemented with 3% sucrose for 45 days produced over 31 mg/g dry wt valepotriates.