• Applied Biological Chemistry
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• v.35 no.2
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• pp.106-109
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• 1992

To investigate the biosynthetic pathway leading to artemisinin, the putative precursors, arteannuic acid and 11,12-dihydroarteannuic acid, were incubated in a cell-free system. For the experiment with dihydroarteannuic acid, artemisinin was generated in tumor homogenate. These results showed that dihydroarteannuic acid could be converted to artemisinin enzymatically. However, the experimental condition failed to convert arteannuic acid into 11,12-dihydroarteannuic acid.

• Applied Biological Chemistry
• /
• v.35 no.2
• /
• pp.99-105
• /
• 1992

Artemisia annua contains the antimalarial principle, artemisinin. The possibility of the production of this compound through tissue culture technique was studied. The optimum combinations of hormones for the induction of callus were p-chlorophenoxyacetic acid(pcPA) and 6-benzylaminopurine(BAP) or pcPA and N-isopentenylaminopurine(2iP) in 0.05 mg/l each. For the growth of callus, the same combination of pcPA and BAP was optimum in concentrations of $1.0\;{\mu}M\;and\;0.5\;{\mu}M$, respectively, and the optimal concentration of sucrose was also found to be 2%(w/v). Tissue culture from the crown gall grew faster than normal callus. In the suspension culture broth and the cells of normal callus or Agrobacterium-transformed tumors, arteannuic acid and 11,12-dihydroarteannuic acid were found together with common phytosterols, whereas artemisinin was not found.