Carbohydrates are organic compounds made of carbon, hydrogen, and oxygen. They include sugars (monosaccharides and disaccharides) and starches (polysaccharides). Common carbohydrates discussed in the document include glucose, fructose, sucrose, starch, lactose, dextrose, inulin, dextrin, gums, mucilages, sodium alginate, agar, pectin, cellulose, and their sources, preparations, properties, and uses. Tests are described to identify the presence of carbohydrates like Molich's test, Benedict's test, Barfoed's test, and Fehling's test.

4. Definition
• Carbohydartes are aldehyde or ketone
alcohals containing carbon , hydrogen and
oxygen in which the hydrogen and oxygen
are in the same ratio as in water.

5. Cont…
• These are first product formed in photosynthesis.
• These are the products from which by subsequent
organic reaction occur,the plant synthesize a great
number of other constituents.

7. Test for carbohydrates
• Molich’s test
• Take a small quantity of sample, add Molich’s
reagent , add small quantity of Sulphuric acid along
the walls of the test tube reddish brown ring will
produce at the junction of two layer.

8. Benedict’s Test
• Take 5ml of the Benedict reagent , add 8drops of
carbohydrates boil it on flame or in water bath for
two minutes.
• Red/green/yellow ppt form

9. Barfoed’s test
• Take 5ml of the Barfoed’s reagent than add 2ml of
the carbohydrates boil it for three minutes in water
bath.
• Brick red ppt will form

10. Seliwanoff’s test
• Take 5ml of the reagent then add 2ml of the sample
carbohydrate in it.
• Rapid reaction form red color which indicate
presence of aldose
• Slower reaction will form pink color

11. Fehling’s test
• Take 2ml of the sample , add 1ml of the Fehling’s
reagent in it and heat it.
• Deep blue ccolor will be given
by sucrose

13. Types
• These are of following two types
I. Monosaccharides
II. Polysacchrides

15. Monosacchrides
• The compounds which do not hydrolyzed into
simple sugars are called monosacchrides.
Or
• Chemically defined as a substance belonging to
carbohydrate group that is ketonic or aldehydic
substitution product of a polyhydroxy alcohal.
• They also known as sugars.

16. Cont….
• Diose do not exit in nature e.g hydroxyacetaldehyde
• But ketonic and aldehydic triose do exist e.g
glyceraldehyde and dihydroxyacetone
• It exist in the form of esters
• Some organism oxidized glycerine
• Hexoses are very important
• They are first detectable sugar synthesized by plants

17. Glucose chain structure

18. Alpha glucose Beta glucose

19. Structure
• There are 16 possible aldo-hexoses and 8
ketohexoses
• If we consider both alpha and beta forms it permit
48 isomers
• Only two occur in free satete in plants
I. D-fructose
II. D-glucose

20. Cont…
• Both are found in sweet fruits , honey and invert
sugar.
• Glucose and other hexoses can exist in both cyclic
and straight chain structures.

21. Disaccharides
• The compound which on hydrolysis yeild two
monosaccharides is known as disaccharide.
• Trisaccharides which yeild 3 monosacchride.
• Tetrasacchrides which yeild 4 monosacchrides and
so on .
• Examples
Maltose , Sucrose

22. Sucrose

23. Sucrose

24. Sucrose
• Botanical origin : Sacchrum officinarum
• Family : Gramineae
• Part used : dried stems
• Constituent : glucose and fructose
• Uses : It is used as demulcent, bacteriostatic,
preservative . It is used as to mask up disagreeable
taste in troches and tablets.

25. Sucrose

26. Starch

27. Starch
• Source
 Maze (Zea mays) Family : Gramineae
 Potato (Solanum tubersum) Family: Solanaceae
• Parts used : grains of maize , tubers of potato
• Consitutents: It consist of amylose and
amylopectin.
• Uses
• It is used as a tablet disintergrant , adsorbent ,
binder , emollient and as a antidote in Codein
poisoning.

28. Amylose Amylopectin

29. Caramel

30. Caramel
• Source
 Sugar
• Preparation
It is obtained by heating glucose or sugar with
alkali , alkaline carbonate or a trace of mineral acid
untill sweet taste of sugar is destroyed and uniform
dark brown mass is formed.
• Uses
• It is used as colouring agent.

31. Purification of caramel

32. Xylose

33. Xylose
• Source
 Straws
 Corn cobs
• Praparation
• It is obtained by boiling corn cobs , straws or other such
materials with dilute hydrochloric acid to hydrolyze the
xylan polymer which is broken down to yeild xylose.
• Uses
• It is used as a diagnostic agent in disorders due to
intestinal malabsorption e.g Crohn’s disease , Radiation
enteritis and pellagra.

34. Xylose

35. Xylose

36. Liquid glucose

37. Liquid glucose
• Botanical origin : Zea mays
• Family : Gramineae
• Constituents : It consist of dextrose , dextrin ,
maltose and water.
• Uses : It is used as a sweeting agent , tablet binder ,
diluent and tablet coating agent.
• Preparation : It is prepared by controlled hydrolysis
of starch .

39. Fructose

40. Fructose
• Sources
• It is obtained from
 Honey
 Sweet fruits
 Inulin
• Preparation
• It is prepared by inversion of aqueous solution of
sucrose and subsequent separation of fructose
from glucose . When sucrose is hydrolyzed glucose
and fructose are obtained in equal quantities .

41. Cont…
• Uses
• It is used as electrolyte replenisher and fluid
nutrient .

42. Fructose

44. Lactose

45. Lactose
• Source
 Milk of Bos taurus
• Preparation
• Lactose is crystalized from Whey . Impure crystals
are redissolved in water . Charcoal is added to
decolourize it . Recrystallization gives us lactose.
• Uses
• It is used as a nutrient , tablet binder , tablet
diluent .

46. Lactose

47. Dextrose

48. Dextrose
• Source
 It is obtained from grapes and fruits .
 It can also be obtained by hydrolysis of certain
natural glycosides.
• Preparation
• It is prepared by control hydrolysis of starch.
• Uses
• It is used as a nutrient, sweeting agent , tablet
binder, coating agent . It is part of a anticoagulant
solution.

49. Cont…
• Its structure is same as that of the glucose.
• D Glucose is known as dextrose.

50. Inulin

51. Inulin
• Source :
 Allium cepa
or
 Allium sativum
• Uses
• It is used as fermantive identifying agent for
bacteria.
• In lab it is used in evaluation of renal function.
• Weight loss , relieve of constipation, food additive
are also its uses.

52. Inulin

53. Dextrin

54. Dextrin
• Source
 Maze
 Potato starch
• Uses : It is used as a nutrient , binder , thickening
agent and adhessive for surgical dressing .

55. Dextrin

57. Gums and mucilages
• Gums are natural plant hydrocolloids which may be
anionic or nonionic or sakts of polysaccharides .
• These are frequently produced in higher plants as a
protective after injury.
• These are heterogenous in composition.
• Upon hydrolysis it yeild arabinose , galactose,
glucose, mannose,xylose and other uronic acids.
• Uronic acid may form salts with magnesium and
calcium.

58. Cont....
• Methyl ether and sulphate esters furthur modify
the hydrophillic properties of polysaccharides.

59. Uses
• It is used as
i. Adhesive
ii. Laxative ( in bulk)
iii. Stabalizer
iv. Emulsifying agent
v. Gelating agent

60. Disadvantage
• Due to hydration of polymer alteration occur e.g
gums are precipitated from solution by alcohal and
by Lead subacetate solution.

61. Difference between gums and
mucilages
• Gums dissolve in water but mucilages form slimy
masses in water.
• Gums are pathological products but mucilages are
physiologic products.

62. Physical properties
• Hydrocolloids may be
A. Linear
B. Branched
• And they may have
A. Acidic
B. Basic
C. Neutral properties

63. Cont...
• Linear polymers are less soluble in water .
• It yeild solutions with great viscosity.
• Branched hydrocolloids form gels rather than
viscous solutions .
• It rehydrate more rapidly than linear hydrocolloids.
• Its drug must be reconsituted before use.

64. Tragacanth

65. Tragacanth
• Botanical origin : Astragalus gummifer
• Family : Leguminosae
• Parts used : gummy exudate
• Consituents :60-70% of bassorin , tragacanthin
• Uses : It is used as suspending agent , emulsifying
agent , adhesive , demulcent , emolient , in cloth
printing and as confectionery.

66. Acacia

67. Acacia
• Botanical origin: Acacia senegal
• Family : Leguminosae
• Part used : gummy exudate
• Constituents : arabin , branched polysaccharides
which on hydrolysis yeild L-arabinose,D-Galactose,
D-glucironic acid , 12-15%water and enzymes
oxidases , peroxidases , pectinases.

68. Cont…
• Uses: It is used as suspending agent , binding agent,
demulcent , emollient and adhesive .

69. Sodium aliginate

70. Sodium aliginate
• Botanical origin : Macrocystis pyrifera
• Family : Lessoniaceae
• Part used : brown seaweed (algae)
• Constituents : sodium salts of alginic acid and major
component is Mabburonic acid
• Uses : It is used as suspending agent , sizing ,
thickening agent , gel forming agent and in food
industry ( ice cream , chocolate milk )

72. Agar

73. Agar
• Botanical origin : Gelidium cartilagineum
• Family : Sphaeeococcaceae
• Parts used : dried colloid concentrate from
decoction of algae
• Constituents : agarose and agaropectin
• Uses : It is used as laxative , suspending agent ,
emulsifying agent , lubricant and disintegrant

74. Pectin

75. Pectin
• Botanical origin : Citrus limon
• Family : Rutaceae
• Parts used : peels ( lemon peels )
• Constituents :It consist of partially methoxylated
polyglacturonic acid joined by alpha 1-4 linkage,
not less than glacturonic acid, 6.7% methoxy group
• Uses : It is used as demulcent , emulsifying agent ,
bacteriostatic and pharmaceutical add.

76. Pectin
•

78. Cellulose

79. Cellulose
• Botanical origin : Gossypium hirsutum
• Family : Malvaceae
• Part used : capsules
• Consituent : It consist of beta linked linear
glucopyranosyl polymer
• Uses : It is used in textile , pharmacy , medicine . It is
used as a surgical dressing and serves as a mechanical
protectant .

80. Cellulose

82. Powdered cellulose

83. Cellulose derivatives
Powdered cellulose
It is prepared by processing alpha cellulose as a
pulp from fibrous plant material .
It is avaliable in various grades.
It range from free flowing to coarse non flowing
powder.
It is used as a binder and disintegrating agent.

84. Microcrystalline cellulose

85. Microcrystalline cellulose
It is prepared by partial depolarization by treating
alpha cellulose from fibrous plant pulp with mineral
acids.
It is used as a diluent in tablet production.

86. Methyl cellulose

87. Methylcellulose
It contain not less than 27.5% and not more than
31.5% of methoxy group.
It prepared by reaction of cellulose with caustic soda
and methyl chloride.
In water it swells and form a clear to opalescent ,
viscous , colloidal suspension.
•Uses
It is used as laxative , cathartic , suspending agent and
topical protectant .

88. Sodium carboxy methylcellulose

89. Sodium carboxymethylcellulose
It is sodium salt of a polycarboxymethyl ether if
cellulose.
It is hygroscopic agent.
Uses
It is used a suspending and thickening agent ,
excipient . It is used as a laxative in bulk quantities.