Effects of gibberellic acid on hairy root cultures of Artemisia annua: Growth and artemisinin production

Abstract

Artemisinin (AN), a potent antimalarial drug that has been used for centuries as a folk remedy in China, is an effective treatment against quinine-resistant strains of Plasmodium. It can be produced through the in vitro culture of genetically transformed (hairy) roots. The effect of gibberellic acid (GA3) on the growth and secondary metabolite production of hairy roots of Artemisia annua was investigated. Six different concentrations of GA3 were tested in shaker flasks to determine the optimum concentration. GA3 levels of 0.01–0.001 mg/l (28.9–2.89 µM) provided the most significant increase in biomass, and 0.01 mg/l (28.9 µM) produced the highest amount of AN. Investigation of growth kinetics showed that the use of GA3 at 0.01 mg/l (28.9 µM) increased the growth rate of hairy roots of A. annua by 24.9%. Thus, the cultures treated with GA3 reached stationary phase faster than control cultures.