احمد آقایی

Tropane alkaloids, hyoscyamine and scopolamine are well-known secondary metabolites produced by many species of Solanaceae family such as Atropa belladonna L. medicinal plant. These valuable pharmaceutical compounds have anticholinergic, antispasmodic and sedative properties. The objective of present study was to investigate the effects of various silver nanoparticle (AgNPs) concentrations (0, 25 and 50 ppm) on deadly nightshade's hyoscyamine and scopolamine contents under in vitro conditions. The seeds of A. belladonna were surface sterilized and germinated on Murashige and Skoog (MS) solid medium with a 16 h photoperiod. After 30 days, the produced plantlets were cultured in MS media containing different concentrations (0, 25 and 50 ppm) of AgNPs for one week. At the end of the experiment, shoots and roots of the propagated plantlets were harvested and frozen in the liquid nitrogen and then transferred to -80 ºC freezer. After total alkaloids extraction, the extracts were analyzed using quantitative high performance liquid chromatography (HPLC) for the determination of hyoscyamine and scopolamine contents. Results indicated that scopolamine content increased significantly (about 3-4.5-folds compared to controls) in root samples of treated plants with both concentrations of AgNPs. In the other hand, hyoscyamine amounts elevated (about 1.5-fold) in shoot samples of treated plants in both concentrations. However, treatment of deadly nightshade plants with AgNPs caused to reduction in scopolamine content of shoots and hyoscyamine level of roots. In conclusion, we proposed that AgNPs could as suitable elicitor to stimulate tropane alkaloids accumulation in solanaceous plants especially A. belladonna.