Methyl jasmonate and iron oxide nanoparticles act as elicitors to stimulate production of bioactive antioxidants and metabolites in the in vitro callus cultures of Bergenia ciliata (haw.) Sternb
Tauqeer Sardar, Muhammad Ishtiaq, Muhammad Waqas Mazhar, Mehwish Maqbool, Ihab Mohamed Moussa, Wajid Zaman, Eman A. Mahmoud
Abstract
• Iron oxide nanoparticles and methyl jasmonate stimulate critical secondary metabolites in Berginia plants. • Stimulation increase the activities of phenylalanine ammonia-lyase, superoxide dismutase , peroxidase , catalase , and ascorbate peroxidase . • In vitro callus elicitation with iron oxide nanoparticles and methyl jasmonate is an effective measure to enhance bergenin contents and bioactive antioxidants. In vitro callus cultures of Berginia ciliata were used to evaluate different ratios of iron oxide nanoparticles and methyl jasmonate for elicitation, with the goal of improving callus morphological features and bergenin biosynthesis. Shoot explants were cultured using MS (Murashige and Skoog) media supplemented with three elicitation concentrations of iron oxide nanoparticles (30, 60, and 90 ug/l) and three elicitation concentrations of methyl jasmonate (50, 75, and 100 uM). The results were compared to the control without elicitor treatment. All the elicitation treatments significantly enhanced the phytochemical contents. In vitro callus elicitation with 75 uM MeJ and 90 ug/l iron oxide nanoparticles proved as the best among tested elicitation concentrations. The elicitation improved the water contents and fresh and dry weights of the callus. The callus elicitation with 90 ug/l iron oxide nanoparticles increased the callus moisture contents by 16%. The elicitation treatments affected callus color traits and improved the callus compactness. Callus elicitation increased the activities of bioactive antioxidants such as phenylalanine ammonia-lyase, superoxide dismutase , peroxidase , catalase , and ascorbate peroxidase . The contents of bergenin, a major phytochemical, were found enhanced under elicitor treatments. Furthermore, contents of total phenolics and flavonoids improved upon elicitation. The in vitro callus elicitation resulted in better antioxidant potential for B. ciliata as assessed through the DPPH free radical scavenging protocol. The callus elicitation with 90 ug/l iron oxide nanoparticles increased DPPH scavenging percentage by 68%. In vitro callus elicitation with iron oxide nanoparticles and methyl jasmonate is an effective measure to enhance bergenin contents and bioactive antioxidants in the callus cultures of B. ciliata .