Assay of steroidal sapogenin

Powdered material (0.2 g) was extracted with 200 ml of petroleum ether for 6 h using the soxhlet apparatus. Then the residue of plant material was extracted with methanol. The resulting petroleum ether and methanol extracts were reduced in rotary evaporator and stored at 4 °C until further use in the experiment. Steroidal sapogenin analyzed by gas liquid chromatography (Ebrahimzadeh and Niknam 1999). A Shimadzu GC-16A equipped with a flame ionization detector and 1.6 m × 3.2 mm i.d. glass column packed with 5% SE-30 was used. Operation temperatures were 280 °C for the oven and 290 °C for both the injector and detector block. Nitrogen was used as carrier gas at a flow rate of 50 ml min⁻¹. Flow rates of hydrogen and air were 55 and 400 ml min⁻¹, respectively.