جستجوی مقالات مرتبط با کلیدواژه « اسید آسکوربیک » در نشریات گروه « بیوتکنولوژی و ژنتیک گیاهی »

 The roots and stolons of Glycyrrhiza species constitute one of the most important crude drugs in the world and contain a large amount of glycyrrhizin, an oleanane-type triterpenoid saponin. Tissue culture and callus production in licorice species are prerequisites for studies on secondary metabolites and cell transformation. In order to effect of antioxidant to reduce the browning and growth of callus, was used Ascorbic Acid and PVP in different levels. Also in order to influence these antioxidants in the callus growth index, were cultured both species as cell suspension. Callus was produced from hypocotyl related to two weeks’ seedlings. Callus was induced from NAA (0.5 mg/L) and BA hormones (2 mg/L) as well as ascorbic acid and PVP treatments at different concentrations as two separated factorial experiments based on CRD design. The results showed that in consecutive sub culture 1200 mg/L of PVP had the least generation, necrosis and the most callus production in both species. Whereas, in cell suspension, with increasing PVP concentration, was decreased callus growth index and 1200 mg/L PVP has shown the lowest callus growth index in both species. It can be said that PVP absorb NAA and BA hormones in cell suspension and therefore it was reduced concentration of hormones in medium. Ascorbic acid treatment with 80 and 100 mg/L had the highest callus growth index in both species respectively and it is recommended for cell suspension culture in licorice.

To study of some photosynthetic and defense genes expression in Spinacia Oleracea (cv. Vienna) and Brassica napus (cv. Falcon) seeds were grown at growth room. In a series of primary experiment a varied range of stress treatment with different concentration were compared. Finally, three treatments included methyl viologen, silver nitrate and 3-amin-trizoil have been selected for further experiment. All treatments were sprayed on the leaves at the maximum of vegetative growth stage. A CRD (completely Randomized Design) order has been used with four replicates. In order to assess cellular oxidative levels the TBARM assay has been used. Sampling has been done at intervals 6, 12, 24, 48 and 72 hours from the leaf treated. To analyzed gene expression and northern hybridization, sampling has been done only 48 hours after the leaves had sprayed. Since of so many results, here we have reported all results included percentage of cell death, TBARM amount and gene expression, for all the treatments only 48h after treatment sprayed. The results showed all treatments have altered the amount of cell death, TBARM and gene expression via increase of reactive oxygen species (ROS). The expression of photosynthetic gene RBCS declined by increasing of stressful treatment concentration. Sprayed pre-treatment ascorbic acid caused relative gene activity increase up to 50%. Also, this improved the physical damage and decline of TBARM by quenching of ROS. For the rest of genes although there were some differences among gene expression in depend on which plant or treatment has been checked out, but in general all genes showed a positive response to stressful treatments. For these genes with no exception using pre-treatment of ascorbic acid caused some altered toward control expression.