ISOLATION AND IDENTIFICATION OF Β-SITOSTEROL FROM ZYGOPHYLLUM FABAGO L. HERB USING SUBCRITICAL CO₂ EXTRACTION.

THE AIM OF STUDY: β-Sitosterol is a bioactive phytosterol with recognized anti-inflammatory, hypocholesterolemic, and immunomodulatory properties. While Zygophyllum fabago L. is known to contain steroidal compounds, systematic studies on the isolation of pure β-sitosterol from this species are limited, particularly regarding the use of green extraction technologies and the achievement of high-purity yields for industrial applications. This study aimed to isolate and identify β-sitosterol from the herb of Z. fabago L. utilizing subcritical CO2 extraction as an environmentally sustainable and selective methodology for nonpolar compounds.

MATERIALS AND

METHODS

β-Sitosterol was isolated from the herb of Zygophyllum fabago L. using subcritical CO2 extraction (57-65 atm, 18-27 °C, 6 L/h). The crude extract was purified via vacuum liquid chromatography (VLC) on silica gel 60 and recrystallized from methanol, with purity monitored by TLC (UV 254/366 nm and H2SO4 visualization). Identification was performed using 1H and 13C NMR spectroscopy and the structure was confirmed by comparison with literature data.

RESULTS

The subcritical CO2 extraction yielded 20 g of crude extract (2.3% yield). The purification process resulted in 1.0 g of pure β-sitosterol, representing a 5% yield relative to the crude extract. TLC analysis showed a single characteristic spot, and NMR data definitively confirmed the structure, identifying key signals such as the C-3 hydroxyl group, the Δ5 double bond, and the characteristic branched aliphatic side chain.

CONCLUSION

These results demonstrate that Z. fabago L. is a high-yielding natural source of β-sitosterol. Furthermore, the study validates subcritical CO2 extraction as a highly effective and selective approach for the preparative isolation of phytosterols from plant matrices, offering significant advantages in terms of purity and environmental impact.