Triterpene saponins from the halophyte <i>Anabasis setifera</i> exhibit anti-SARS-CoV-2 properties

Halophytes are well-known as a rich source of health-promoting phytochemicals. This study aimed to elucidate the chemical constituents and antiviral potential of the halophyte <i>Anabasis setifera</i> Moq., growing in the desert areas of Egypt. Six triterpenoid oleanane saponins (1-6) were purified using several chromatographic procedures and identified <i>via</i> HRMS and NMR spectroscopic analyses, with solysaponin B-D being reported for the first time. Additionally, three known triterpene saponins (4-6) were identified as spinacoside C (4), betavulgaroside IV (5), and (3β)-3-(β-d-glucuronopyranosyloxy)olean-12-en-23,28-dioic acid (6). The isolated triterpene saponins were able to inhibit the severe acute respiratory syndrome corona virus 2 (SARS-CoV-2). Our study provides valuable insights into the promising antiviral activity of saponins 1, 2 and 4 with IC₅₀ values ranged between 2.339 and 6.837 μg mL^-1.