Phytochemical analysis: Alkaloid detection: Thepowdered sample was dissolved in 2ml of dilute HCL and filtered, this extractwas subjected to varied alkaloidal reagents.Dragendorff’s reagent:1 or 2ml of Dragendorff reagent when added to the extract, results in red-orangeprecipitates which is a positive test. (Tiwari.
,2011 Willow)Hager’s reagent:Few ml of sample was mixed with few drops of the saturated solution of picricacid. Prominent yellow precipitate confirms the alkaloid presence. (Bhandary; Tiwari;Pandey)Mayer’s reagent:To a few ml of extract, two drops of Mayer’s reagent are added along the sidesof tubes. Yellow or white precipitate indicates the presence of alkaloids.
(Pandey;Banu, Maria)Wagner’s reagent: Fewdrops of Wagner’s reagent are added to few ml of filtrate along sides of the testtube. Reddish-brown precipitate evident the presence of secondary metabolitealkaloid. (Chanda; Maria)Detection of phenolic compounds:Ferric chloride test: Tothe aqueous extract few drops of 5% ferric chloride solution is added. Presenceof phenolic compounds can be observed with dark green or bluish black colour. (Banu;Jaradat; Tiwari)Lead acetate test: Theextract wass dissolved in 3ml of 10% lead acetate solution. White precipitate canconfirm the presence of phenolics. (Banu; Pandey)Tannin detection:Gelatin test: 2mlof 1% gelatin containing solution with 10% sodium chloride was added to thesample extract.
Appearance of white precipitate manifests the presence oftannins. (Tiwari; Pandey; Bhandary)Ferric chloride test:5% of ferric chloride solution is added to 2ml of extract. A dark green or bluecolour disclose the tannin presence. (Rattana; Maria) Flavonoid detection:Alkaline reagent:10 % of ammonium hydroxide solution is mixed with the sample extract. Flavonoiddetection can be done with yellow fluorescence. (Jaradat; banu; Bhandary)Shinoda test:1ml of ethanol and drops of conc.
HCL was added to the extract in isopropylalcohol, red colour confirms the aurones, chalcones presence. If there is nocolour change formation of orange, red colouration in addition of metallicmagnesium indicates the flavones and flavonols presence. (Rattana; Jaradat; Sherani)Sodium hydroxide test: Fewdrops of 10% sodium hydroxide was added to extract in isopropyl alcohol toobtain a yellowish red or orange or blue colour which confirms the flavones,flavonols presence. (Maria; Sherani) Detection of phytosterols: Liebermann-Burchard reaction: Tothe extract, add 2ml of acetic anhydride and few drops of concentrated. H2SO4along the sides. Colour change to blue evident the steroidal compound presence.(Boxi.
,2010; banu; Kumar)Detection of glycosides:Theextract is hydrolysed with concentrated HCL and the filtrate is subjected forthe following test.Modified Borntrager’s test: Add3ml of chloroform to the hydrolysed extract and shaken. Chloroform layer wasseparated and mixed with 10% ammonia solution. Formation of pink colour inammoniacal layer show the presence of anthranol glycosides (Tiwari; Banu)Legal’s test: Add sodium nitroprusside in pyridine andsodium hydroxide to the extract. Colour change from pink to red reveal thecardiac glycosides presence. (Banu; Tiwari)Kellar- Kiliani:2ml of glacial acetic acid with 1drop of ferric chloride solution and 1ml of conc.
H2SO4were added to the extract. Brown ring formation confirms the presence ofcardiac glycosides. (Obianime and Uche.,2008; Rattana; Bhandary)Terpenoid detection:Salkowski’s test: 3mlof concentrated sulphuric acid with 2ml of chloroform was added to the extract.Presence of triterpenes can be observed with reddish brown colour. (Obianime.
,2008; Rattana; Sherani)Copper acetate test:To 2ml of extract few drops of copper acetate solution were added. Emeraldgreen colouration confirms the diterpenes presence. (Tiwari Pandey)Saponin detection:Froth test:The plant sample is diluted with distilled water up to 20ml and shakenvigorously.
Foam formation suggests the saponin presence. (Adegoke.,2010;Rattana; Sherani) Test for CarbohydratesMolisch test:To few drops of extract 2 drops of alpha-naphthol solution and conc. sulphuric acidis added to obtain a violet ring formation that confirms the presence. (Tiwari;Boxi.
,2010; Jaradat)Barfoed’s test: Thefiltrate was treated with equal volume of Barfoed’s reagent and kept in boilingwater bath for 2 mins. The test tube is then cooled, red colouration indicatesthe presence. (Boxi.
,2010)Benedict’s test:The extract was treated with Benedict’s reagent and heated. Reducing sugarpresence was observed with orange-red precipitate. (Jaradat;Banu; Bhandary)Fehling’s reagent:The extract is hydrolysed with dil. HCL and an equal volume of Fehling’s A& B were added and heated. Red precipitate was observed.
(Akinyemi;Tiwari) Detection of proteins and amino-acids:Millon’s test: 2mlof extract is added with Millon’s reagent. White precipitate confirms theprotein presence (Jaradat;Banu)Xanthoproteic test: Tofew drops of extract conc. nitric acid is added to the sides of the test tube.Yellow colour observed indicates the protein presence.
(Tiwari)Ninhydrin test:0.25% w/v ninhydrin reagent was added to the extract and boiled for 1-2 min toobtain blue colour. This indicates the amino-acid presence.