A. Norozi; B. Hosseini; M. Jafari; M. Farjaminezhad
Abstract
Henabne(Hyoscyamus reticulatus L.) is a rich source of tropane alkaloids including hyoscyamine (Hyos) and scopolamine (SCP), widely used in pharmaceutical field. The aim of the present study was to assess the effect of different concentrations (0, 50, 100 and 200 µM) of methyl jasmonate (MeJA) ...
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Henabne(Hyoscyamus reticulatus L.) is a rich source of tropane alkaloids including hyoscyamine (Hyos) and scopolamine (SCP), widely used in pharmaceutical field. The aim of the present study was to assess the effect of different concentrations (0, 50, 100 and 200 µM) of methyl jasmonate (MeJA) at two different times of exposure (24 and 48 h) on growth, antioxidant enzymes activity, tropane alkaloids content, and the expression level of hyoscyamine-6-beta-hydroxylase (h6h) gene in H. reticulatus hairy root cultures. The results showed that MeJA at high concentration (200 µM) led to the decline of fresh and dry weight of hairy roots. Catalase (CAT), guaiacol peroxidase (GPX) and ascorbate peroxidase (APX) activities were significantly increased by MeJA, especially at 200 µM in elicited hairy roots. As well, CAT and GPX activities, but not of APX, were also affected by exposure time of MeJA. According to the GC/MS analysis, the highest percentage of SCP (13.96%) and Hyos (21.9%) were respectively obtained when hairy roots were exposed to MeJA at concentrations of 100 and 200 µM for 48 and 24 h, which were, respectively, 1.6- and 1.25-fold higher than those in the control roots. According to the results of semi-quantitative RT-PCR analysis, the highest expression of h6h gene (6-fold higher than in the control) was obtained after 24 h exposure to 100 µM MeJA. These results indicate that MeJA, due to stimulation of the expression of key genes involved in the biosynthetic pathway of tropane alkaloids, could be used as an effective elicitor for increased production of Hyos and SCP.
I. Bernousi; M. Jafari; J. Ahmadi Dizaji
Abstract
This research was aimed to investigate the effect of two infection methods (immersion and spray) and two Agrobacterium rhizogenes strains (strain A13 and GMI9534) to induce hairy roots on different explants (hypocotyl, cotyledon, leaf, and stem node) of Teucrium chamaedrys. Strain GMI9534 could not induce ...
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This research was aimed to investigate the effect of two infection methods (immersion and spray) and two Agrobacterium rhizogenes strains (strain A13 and GMI9534) to induce hairy roots on different explants (hypocotyl, cotyledon, leaf, and stem node) of Teucrium chamaedrys. Strain GMI9534 could not induce hairy roots in any of the explants, whereas strain A13 was only able to induce hairy roots in leaf and stem node explants. Infection by immersion method was more successful, with higher root induction efficiency (more than 73.3%), and leaf explants showed the highest induction frequency (83.3%). The transformed hairy root lines were confirmed by PCR using rolA and rolB gene-specific primers. Significant differences were shown among the 20 independent hairy root lines cultured on growth regulator-free MS solid medium for total root length and for the root branching. These variables were stable across subcultures and hence seven independent hairy root lines were selected based on these growth properties. Subsequently, the cultures for these hairy root lines were established in half-strength MS liquid medium to monitor their biomass production during a 90-day culture period. Considerable variations were observed in growth capacity among the lines. Line TC-HR-16 produced the highest fresh biomass (9100 mg/30 ml culture medium), a 455-fold increase over initial inoculum, during the 10-weeks culture period. The best-characterized hairy root lines, resulted in this study, can be used to improve the production of secondary metabolites of pharmaceutical values of T. chamaedrys.
