GC-MS Identification and GC-FID Quantitation of Terpenoids in Ononidis spinosae Radix

A GC-MS method has been developed for the qualitative analysis of sterol and triterpene (terpenoid) constituents of Ononis spinosa L. (spiny restharrow) root without derivatization. beta-Sitosterol, campesterol, stigmasterol, stigmastan-3,5-diene sterol compounds and the triterpene derivatives beta-amyrin and a-onocerin were identified. A validated GC-FID quantitative method was developed for measuring beta-sitosterol, the main sterol component, in various extracts of this plant, obtained with organic solvents and by supercritical fluid extraction. The extracts were cleaned by saponifying and then the beta-sitosterol was quantified in the non-saponifiable fractions by GC-FID with an internal standard. In addition, the relative concentrations of the other terpenoids were also determined. The beta-sitosterol content in the non-saponifiable solvent extraction fractions was 0.19-5.5%, that of the supercritical fractions were 4.8-9.2%, depending on the experimental conditions. The hexane and the pilot scale SFE extracts were considered as main sources of terpenoids (71.8%; 93.3%, respectively).