ریشه موئین

Hyoscyamus species such as H. reticulatus L. and H. pusillus L. are rich sources of tropane alkaloids, mainly hyoscyamine and scopolamine, which are used for their mydriatic, antispasmodic, anticholinergic, analgesic and sedative properties. In this study, in the first experiment, the effects of four strains of Agrobacterium rhizogenes (ATCC 15834, A4, A7 and A13) and three explants (leaf, hypocotyls, and cotyledon) on hairy root induction were investigated in both H. reticulatus and H. pusillus species. In the second experiment, the effects of various culture media (MS, 1/2 MS, 1/4 MS, and B5) were evaluated on some morphological and phytochemical traits of hairy roots. The results showed that in H. reticulatus, maximum hairy root induction (78%) was obtained in the cotyledon explant inoculated with A7 strain and maximum hairy roots fresh weight (6.25 g) and dry weight (0.5 g) were recorded in MS medium. In this species, the highest total phenol (3.82 mg GAE g-1 FW) and total flavonoid (7 mg QUE g-1 FW) content were observed in MS medium; however, no significant changes were observed in the activity of antioxidant enzymes of hairy roots cultured in different media. In H. pusillus, the leaf explant inoculated with A13 strain showed maximum hairy root induction (90%), and the highest hairy root fresh weight (5.25 g) and dry weight (0.43 g) were observed in MS medium and the highest total phenol (2.26 mg GAE g-1 FW) and flavonoid (9.22 mg QUE g-1 FW) content were obtained in B5 medium. This study showed that basal culture medium type and plant species had a significant impact on the biomass and phytochemical characteristics of hairy roots.

The hairy roots induced by Agrobacterium rhizogenes due to the stability and mass production in hormone free culture provide an appropriate tissue for secondary metabolite production, and the content of metabolites produced could be affected by bacterial strain. In the current study, the effect of different strains of A. rhizogenes including A4, A13 and 15834 on the percentage of hairy root induction of Echinacea purpurea (L.) moench. in the leaf and hypocotyl explants were studied. In another experiment, total phenolics and polysaccharides content of hairy roots were measured compared to the control (untransformed) roots. The results showed that the percentage of hairy root induction was significantly affected by bacterial strains, so that in E. purpurea leaves incubated by strains A13, 15834 and A4, the hairy root induction was 60%, 40% and 0, and in hypocotyl explants was 85%, 45% and 70%, respectively. Maximum total phenolic compounds were observed in A4 strain. As well, in comparison to control, the polysaccharide content in hairy root induced by strains 15834 and A13 increased and by A4 strain decreased significantly. Differences observed in this study about hairy root induction and secondary metabolites production could be due to different ability of A. rhizogenes strains in T-DNA transferring to plant cells.