Comparative Metabolite Profiling of Different Solvent Extracts of Argemone ochroleuca Sweet and Argemone mexicana Linn Shoots and Roots Using Liquid Chromatography–Mass Spectrometry-Based Metabolomics and Molecular Networking

Argemone ochroleuca and Argemone mexicana are widespread weed species known for being rich in various secondary metabolites. However, a comprehensive understanding of their chemical diversity remains limited. Insufficient information exists on metabolite variation between plant parts and the influence of solvent polarity on metabolite recovery. Therefore, this study aimed to characterize the metabolomic profiles of the shoots and root extracts of both species using solvents of varying polarity to evaluate plant part-specific metabolite distribution and solvent effects on metabolome coverage. Untargeted ultra-high-performance liquid chromatography–quadrupole time-of-flight mass spectrometry (UPLC-QTOF-MS)-based metabolomics and molecular networking were employed for metabolite analysis. Principal component analysis (PCA) did not reveal clear clustering of A. ochroleuca and A. mexicana, suggesting similarities in their metabolomic profiles. A total of 15 and 13 metabolite classes, yielding 59 and 54 metabolites, were identified in A. ochroleuca and A. mexicana, respectively, including flavonoids, terpenoids, phenolic compounds, fatty acids, and monoterpenoids. Argemone ochroleuca exhibited higher metabolite abundance, particularly in methanol and acetone extracts, and with shoots showing higher abundance than roots, with flavonoids being the dominant class. The findings show that LC-MS metabolomics, molecular networking, and careful solvent selection are effective for identifying key metabolites with potential applications in crop protection.