Phytochemical Analysis of Plant Extract

A small portion of the dry extract was used for the phytochemical tests for compounds which include tannins, flavonoids, alkaloids, saponins, and steroids in accordance with the methods of [17 ,18 ] with little modifications. Exactly 1.0 g of plant extract was dissolved in10 ml of distilled water and filtered (using Whatman No 1 filter paper) A blue colouration resulting from the addition of ferric chloride reagent to the filtrate indicated the presence of tannins in the extract. Exactly 0.5 g of the plant extract was dissolved in 5 ml of 1% HCl on steam bath. A millilitre of the filtrate was treated with few drops of Dragendorff's reagent. Turbidity or precipitation was taken as indicative of the presence of alkaloid. About 0.2 g of the extract was dissolved in 2 ml of methanol and heated. A chip of magnesium metal was added to the mixture followed by the addition of a few drops of concentrated HCl. The occurrence of a red or orange colouration was indicative of the flavonoids. Freshly prepared 7% blood agar plate was used and wells were made in it. The crude extract dissolved in 10% methanol was used to fill the wells bored in the blood agar plates. Ten percent methanol was used as a negative control while commercial saponin solution was used as a positive control. The plates were incubated at 35°C for 6 h. complete haemolysis of the blood around the extract was indicative of saponin. About 0.5 g of the extract was dissolved in 3 ml of chloroform and filtered. Concentrated H₂SO₄ was carefully added to the filtrate to form lower layer. A reddish brown colour at the interface was taken as positive for steroid ring.