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Clinical pharmacy PharmD program Third level Phytochemistry-1 (PG-504)

Pectin is polysaccharide, which consists mainly of -D-galacturonic acids

linked together by 1➔4--glycosidic linkages in a linear or helix-form chains

(20-100-200 units); and contains various proportions of neutral monosaccharide
(usually 10-25%), namely; L-rhamnose, D-galactose, D-xylose and L-fucose. D-

Galacturonic acid chain is partly found as methyl ester.

Occurrence: Apples (15%), citrus fruits (30%), wood (very small proportion).

Preparation of Pectin:

▪ Pulp of apples (Malus domesticus, Fam. Rosacease) is heated with dil. acid to

convert insoluble form (Protopectin) to soluble form (Pectin), and then filtered.

▪ Pectin can be precipitated by alcohol, washed and dried.

Character of Pectin:

▪ Odorless, yellowish-white, coarse or fine powder with mucilaginous taste.

▪ Soluble in H 2O to form viscous opaque colloidal solution, acidic to litmus

(1: 20).

▪ A solution (10%) sets into a stiff gel on cooling.

Jelly Grade:

It is the number of pounds of sucrose that one pound of pectin can carry in

a jelly of standard acidity “pH = 2.8-3.5” and water content. “Sucrose must be

about 65 - 70%”

Uses of Pectin:

1) In ulcer and gastritis.

2) In Diarrhea and gastroenteritis

3) In wound treatment as bacteriostatic.

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