Metabolite characterization and in vitro antiplasmodial potential assessment of Sonchus arvensis L. callus under glutamine treatment

This study investigates the effects of glutamine supplementation on the morphology, anatomy, biomass, production of secondary metabolites, in-vitro antioxidant, and antiplasmodial activity of Sonchus arvensis L. callus. Callus was induced from leaf explants on Murashige and Skoog (MS) medium supplemented with 1 mg/L 2,4-Dichlorophenoxyacetic acid (2,4-D) and 0.5 mg/L 6-Benzylaminopurine (BAP), and subsequently treated with glutamine (0-350 mg/L). Glutamine supplementation affected callus morphology and anatomy, yielding mainly compact callus types. Gas Chromatography-Mass Spectrometry (GC-MS) analysis revealed a variety of metabolites in the callus extracts. Notably, a total of 51 metabolites were detected only in the glutamine-treated callus. In silico prediction suggested antioxidant and antimalarial potential for probable major compounds, including methyl α-D-glucopyranoside, methyl β-D-glucopyranoside, n-hexadecanoic acid, (9Z,12Z)-9,12-octadecadienoic acid, and stigmasterol. In vitro assays highlight that glutamine supplementation enhanced the 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical scavenging activity by up to two-fold and increased the Plasmodium falciparum inhibition by up to three-fold compared to the control callus, with 250 mg/L glutamine being most effective. These findings provide novel insights into the glutamine's role in S. arvensis L. callus culture and demonstrate its potential to increase the valuable bioactive compounds production, particularly those with antimalarial activity.