چكيده لاتين
Nepeta mahanensis Jamzad & M. Simmonds is a valuable medicinal plant native to Iran. The aim of this research was to optimize the callus culture and plant cell suspension culture of N. mahanensis to investigate the effects of various concentrations of salicylic acid on growth indicator and the content of some phenolic compounds. For callus induction, leaf, hypocotyl, and stem explants were cultured in Murashige and Skoog (MS) medium supplemented with different concentrations of BAP, and 2,4-D hormones under light/dark conditions. After 30 days, the percentage of callus induction, callus diameter, and callus weight were measured. The results showed that the best callus induction was achieved from leaf explants in MS medium containing 2 mg/L of 2,4-D and 1 mg/L of BAP under light/dark conditions. After callus induction, suitable callus was transferred to liquid MS medium supplemented with 2 mg/L of 2,4-D and 1 mg/L of BAP, and incubated on a gyratory shaker at 120 rpm in the dark. The cell suspension culture was then treated with 0, 25, 50, 75, 100, and 150 μM salicylic acid while the cells were in their exponential growth phase (from day 8 to 13 after sub-culturing). The results showed that the activity of phenylalanine ammonialyase, as well as the content of total phenolics, flavonoids, flavonols, anthocyanins, phosphomolybdate, malondialdehyde, H2O2, and fresh weight in all treated cells, had a significant difference compared to the control. Taken together, these findings suggest that different concentrations of salicylic acid caused various changes in cell metabolism through oxidative stress and could be effective for the antioxidant defense systems of cells, which induce phenolic biosynthesis pathways and accumulation. According to the obtained results, 50 and 75 µM of salicylic acid had a positive effect on cell growth and the phenolic compound content in treated cells.
