Alkaloid production in hairy roots of Hyoscyamus albus transformed with Agrobacterium rhizogenes

Abstract

Hairy roots of Hyoscyamus albus were induced from the shoot cultures by transformation with A. rhizogenes strain MAFF 03-01724. The hairy root cultures were tested for growth and alkaloid production (5 tropane alkaloids simultaneously quantified by HPLC) in various media. Half-strength MS and Gamborg BS media containing 3% sucrose gave the highest alkaloid content ( ca 2% dry wt), but only poor growth. On the other hand, fast growth was observed in Woody Plant medium containing 8% sucrose, while the production of tropane alkaloids was relatively low. The addition of KNO 3 (1–50 mM) to Woody Plant medium (3% sucrose) enhanced the growth, and consequently the alkaloid yield in the hairy roots increased remarkably. The hairy roots cultured in the improved medium (Woody Plant medium containing 3% sucrose and 15 mM KNO 3) for 28 days produced over 30 mg tropane alkaloids in one 100 ml flask ( ca 0.8 mg 7β-hydroxyhyoscyamine, 1.7 mg littorine, 1.7 mg scopolamine, 7 mg 6β-hydroxyhyoscyamine and 19 mg hyoscyamine in 50 ml liquid medium).