Biologically Active Compounds of Plants of the Atraphaxis Genus: Chemical Composition and Immunomodulatory Evaluation

This study systematically investigated lipophilic and polar metabolites of <i>Atraphaxis virgata</i> (Polygonaceae) and assessed its immunomodulatory activity in vivo. Supercritical CO₂ extraction of the aerial parts yielded a lipophilic fraction analyzed by means of gas chromatography-mass spectrometry (GC-MS), which identified 42 compounds, including fatty acid esters, sterols, hydrocarbons, and terpenoids. The residual plant meal was subjected to ultrasound-assisted extraction with 70% aqueous ethanol at 30-35 °C, using a solid-to-solvent ratio of 1:8 for 120 min. This polar extract was evaluated for amino acids, proteins, and carbohydrates, while solvent-solvent partitioning with chloroform, ethyl acetate, and water enabled isolation of phenolic- and flavonoid-enriched fractions. Six phenolic constituents, including four flavonol glycosides and two phenolic acids, were structurally confirmed. The extracts were rich in unsaturated fatty acids and water-soluble antioxidants, supporting their nutritional and pharmacological relevance. In vivo evaluation using a cyclophosphamide-induced myelosuppression model in Wistar rats demonstrated stimulation of erythropoiesis and leukopoiesis, confirming immunomodulatory potential. Collectively, this work provides the first comprehensive chemical and biological characterization of <i>A. virgata</i> and establishes a foundation for mechanistic studies and pharmacological validation.