Methyl jasmonate elicitation improves antioxidant and antibacterial activities in Portulaca oleracea

The application of elicitors has been shown to enhance the biological activities of crops and medicinal plants by modulating their phytochemical content. This study evaluated the effect of methyl jasmonate elicitation on the biological activities of Portulaca oleracea. Antioxidant activity of methanol and aqueous extracts from methyl jasmonate-elicited and non-elicited plants was assessed using 2,2-diphenyl-1-picrylhydrazyl (DPPH), ferric reducing antioxidant power (FRAP), and 2,2?- azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) assays. Antibacterial activity was evaluated against Bacillus cereus, Serratia marcescens, Escherichia coli, and Staphylococcus aureus using the well-diffusion method. Toxicity was tested using the brine shrimp lethality assay. The methyl jasmonate-elicited methanol extract showed the highest antioxidant activity with half maximal inhibitory concentration (IC50) values of 1556.52?30.81 ?g/mL (DPPH), 3353.33?29.83 ?g/mL (ABTS), and ferric reducing power of 273.24?3.49 mg ferrous (II)/g dry extract. Only methyl jasmonate-elicited methanol and aqueous extract inhibited the growth of Serratia marcescens, with inhibition zones of 15.1?0.06 mm and 11?0.06 mm, respectively. No inhibition was observed against the other tested bacteria. Toxicity results confirmed the non-toxic nature of all extracts, with median lethal concentration (LC50) values >1000 ?g/mL. Overall, methyl jasmonate elicitation enhanced the antioxidant and selective antibacterial activity of P. oleracea.