A study of the production of essential oils in chamomile hairy root cultures

The active substances in chamomile (Matricaria recutita L.) belong to chemi cally different structural types. The largest group of medically important compounds forming the essential oils are primarily chamazulene, (-)-alpha-b isabolol, bisabololoxides, bisabolonoxide A, trans-beta-farnesene, alpha-fa rnesene, spathulenol and the cis/trans-en-in-dicycloethers. Flavonoids, cou marins, mucilages, mono- and oligosaccharides also have pharmacological eff ects. We studied the production of essential oils in genetically transforme d cultures. Sterile juvenile chamomile plants were infected with A4-Y strai ns of Agrobacterium rhizogenes. They are known plant pathogens and are capa ble of inducing so-called hairy roots. The transfer DNA segment of the Ri-v irulence plasmid of A. rhizogenes becomes integrated in the genome of the p lant cells. The isolated hairy roots grow rapidly on hormone-free media. In order to obtain bacteria-free media, we cultured the transformed roots on Murashige-Skoog (MS) medium supplemented with carbenicillin (800 mg/l). To study the production of essential oils, the clones were propagated on liqui d and solid MS and Gamborg (B5) media, respectively. According to gas chrom atography, the composition of the essential oil of hairy root cultures on d ifferent media was found to be similar, but differing in proportion. The ma in component of the essential oil which was identified by gas chromatograph y and mass spectrometry was trans-beta-farnesene, as in the intact roots.