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1. Detection of Carbohydrates
Small quantities of aqueous extracts of powdered drug
were treated separately with distilled water and filtered.
The filtrates were concentrated and used for various tests
to detect the presence of carbohydrates.
a)Molisch’s Test
The filtrate was taken in a test tube and treated with
1ml of 1% alcoholic α-naphthol solution2 ml of
concentrated sulfuric acid was added along the side of
the test tube Violet color ring at the junction of two
liquids indicates the presence of carbohydrate.

2. b) Fehling’s Test
Small portion of concentrated extract was taken in a
test tube with equal volumes of Fehling’s solution A and
BIt was heated on a Bunsen burner. Formation of
green, yellow or brick red color precipitate indicates
the presence of reducing sugar(s).
c) Benedict’s test
Small portion of the concentrated extract was treated
with equal volumes of Benedict’s reagent and heated
Formation of green, yellow or brick red color
precipitate indicates the presence of reducing sugar(s).

3. d) Barford’s Test
Small portion of the concentrated extract was treated with
equal volumes of Barford’s reagent and heated in a water bath
for five minutes. Formation of red color precipitates at the
bottom of the test tube indicates presence of
monosaccharide(s).
e) Cobalt-chloride
Test 3 ml of test solution was taken in a test tube and treated
with 2 ml of cobalt chloride solution, boiled and cooled. Few
drop of sodium hydroxide solution was added. Appearance of
greenish blue color indicates presence of glucose/ appearance
of purplish color indicates presence of fructose/ upper layer
greenish blue and lower layer purplish color indicates presence
of glucose and fructose.

4. f) Tollen’s Phloroglucinol
Test 2.5 ml of concentrated Hydrochloric acid, 4 ml of
0.5% solution of phloroglucinol and 1-2 ml of test
solution were mixed together and heated. Appearance
of yellow or red color indicates presence of hexose
sugars like galactose.
g) Test for Starch
A small amount of extract was taken in a test tube and
treated with dilute iodine solution. Appearance of blue
color indicates presence of starch.