Investigation of Secondary Metabolites and Their Bioactive Potential in Various <i>Iris</i> Species and Cultivars Grown under Different Cultivation Conditions

This study analyzed the bioactive secondary metabolites in leaves and roots with rhizomes of various <i>Iris</i> species and cultivars (subgenus <i>Iris</i> and <i>Limniris</i>) grown under different conditions. Plants were cultivated in aeroponics and hydroponics and treated with a feather hydrolysate as an alternative nutrient source or arbuscular mycorrhizal fungi (AMF) to promote metabolite production. Phytochemical profiling was performed by using UHPLC-HRMS/MS, aided by in silico fragmentation for compound identification. Chemometric analyses revealed differences in the metabolic profiles between plant parts, including upregulation of phenolic acids, steroids, and <i>C</i>-glycosyl xanthones in the leaves and of stilbenes, triterpenoids, and benzophenones in the roots with rhizomes. Variations between the subgenera <i>Iris</i> and <i>Limniris</i> revealed possible chemotaxonomic markers, while cultivars of the same species showed a close similarity. Hydroponics resulted in upregulation of 232 metabolites, including flavone and isoflavonoid glycosides, compared to 42 upregulated metabolites in aeroponics, like xanthones and benzofurans. Neither feather hydrolysate nor AMF significantly altered the profile of detected metabolites. The correlation of the phytochemical profiles with biochemical assays of the <i>Iris</i> extracts indicated metabolites with cytotoxic, antimicrobial, and anti-inflammatory potential, including both known bioactive compounds (e.g., iridin, phalerin, or <i>p</i>-coumaric acid) and compounds with no published bioactivity data (e.g., irisjaponin A).