2.2. Preparation of extracts
Briefly 100 g of each powdered sample (stems and root) was soaked separately in 500 ml of petroleum ether, chloroform, ethyl acetate, acetone and methanol for 24 h at 40 C on water bath. The obtained extract was filtered by using Whatman No.1 filter paper. Each filtrate was concentrated under reduced pressure on a rotary evaporator till golden viscous mass was obtained. Finally, the prepared extracts were stored at 4 C for further analyses.