Phytochemical Screening of Plant Extracts

The phytochemical screening was done using the standard protocols [21 –28 ]. Test for Alkaloids: 5 ml of extract was concentrated to yield a residue. Residue was dissolved in 3ml of 2% (v/v) HCl, few drops of Mayer’s reagent was added. Appearance of the dull white precipitate indicated the presence of basic alkaloids. Test for Coumarin: 4 ml extract solution was taken; 1–2 drops of water (hot) was added. Volume was made half (UV fluorescence). 10% NH₄OH was added to another half volume (strong fluorescence). Presence of green fluorescence indicated the presence of Coumarin. Test for Saponins: 2 ml extract was shaken vigorously for 30 s in a test tube. Persistence of thick forth even after 30 mins indicated the presence of saponins. Test for Glycosides: 2 ml of extract was dried till 1 ml.1-2 ml NH₄OH was added and shaken. Appearance of cherish red color indicated the presence of glycosides. Test for Reducing Sugars: 0.5 ml of extract was taken and 1ml distilled water was added. 5-8 drops of Fehling’s solution (hot) was added. Presence of brick red precipitation indicated the presence of reducing sugar. Test for steroids: 1 ml extract was dissolved in 10 ml chloroform. Equal volume of conc. H₂SO₄ was added by the side of test tube. Upper layer turned red and sulphuric acid layer turned yellow with green fluorescence. This indicated the presence of steroids. Test for Quinone: 1 ml of extract was taken.1 ml of conc. H₂SO₄ was added. Formation of red color indicated the presence of quinone. Test for Terpenoids: 5 ml of extract was taken and mixed with 2 ml of chloroform. 3 ml of conc. H₂SO₄ was added to form a layer. Reddish brown precipitate formation at the interface formed indicated the presence of terpenoids. Test for Tannins: About 0.5 g of the dried powdered samples was boiled in 20 ml of water in a test tube and then filtered. Few drops of 0.1% Ferric Chloride was added and observed for brownish green or a blue-black coloration. Test for Flavonoids: A portion of the powdered plant sample was heated with 10 ml of Ethyl Acetate over a steam bath for 3 min. The mixture was filtered and 4 ml of the filtrate was shaken with 1 ml of dilute Ammonia solution. A yellow coloration was observed indicating a positive test for flavonoids.