Effect of mechanical vibration on total phenol, alkaloid and antioxidant activity of Hyoscyamus reticulatus callus tissue

Hyoscyamus reticulatus is an important medicinal plant belonging to Solanaceae family. This herb has antispasmodic, antichlorogenic and analgesic characteristics due to tropane alkaloids such as hyoscyamine and scopolamine. Mechanical vibration is one of abiotic stresses which could affect on growth and development of plant cells. In this research, effect of high-frequency mechanical vibration were studied on some growth parameters, total phenolic and alkaloid contents and free radical scavenging activity using 2,2-diphenyl-1-picrylhydrazyl (DPPH) in H. reticulatus calli. Mechanical vibrations were applied at 0, 50, 100 and 150 Hz for 15, 30 and 45 min on the H. reticulatus calli. Response of callus tissue was different on growth, antioxidant activity, phenolic and alkaloid content in various times, and optimum time was observed for 30 min. Mechanical vibration at 50 and 100 Hz increased significantly growth, protein, proline, phenolic and alkaloid contents, and the highest content of these parameters were observed at 50 Hz for 30 min. Carbohydrate content decreased significantly, and the lowest content was identified at 100 Hz for 45 min. Mechanical vibration also decreased lipid peroxidation, and increased radical scavenging activity with decrease of IC50 content especially especially at 50 Hz in 30 min. It seems that mechanical vibration at a proper frequency and time could be a tool for induction of growth and secondary metabolite in plant cells.