Ultrasound-assisted extraction and LC–ESI–MS profiling of triterpenoid saponins from Acanthophyllum elatius roots

Acanthophyllum elatius, a species native to the Irano–Turanian region and belonging to the Caryophyllaceae family, represents a potential source of triterpenoid saponins of interest for natural surfactant applications. This study focuses on the characterization of A. elatius roots and to evaluate the surface-related and biological activities of the resulting saponin-rich extract. Saponins were extracted from the roots of A. elatius using a green ultrasound-assisted extraction method, and their chemical profile was characterized for the first time by LC–ESI–MS analysis. In addition, foaming and emulsifying indices, as well as antibacterial and antioxidant activities of the saponin-rich extract, were assessed under defined experimental conditions. A total of 113 oleanane-type triterpenoid saponins were tentatively identified, with gypsogenin-derived aglycones being the dominant class. The extract exhibited noticeable foaming and emulsifying behavior, along with moderate antibacterial and antioxidant activity. Overall, these findings highlight A. elatius as a novel and renewable source of structurally diverse saponins with potential relevance for bio-based surfactant applications in food, cosmetic, and pharmaceutical formulations.