Which is a fructosan?
Polysaccharides serve storage and structural functions — eg.
1. Starch →
a. Homopolymer of glucose, yield only glucose on Hydrolysis, known as — Glucosan or glucan
b. Formed of α-glucosidic chain
c. Two chief constituents of starch are:
i. Amylose (15-20%) has non branch helical structure
ii. Amylopectin (80-85%) branched chain carbohydrates found in cereals, potatoes legumes etc.
2. Glycogen: -
a. Storage polysaccharides of Animals also known as animal starch.
b. Highly branched chain structure.
c. Yield only glucose on hydrolysis (glucosan)
3. Inulin: -
a. On hydrolysis gives fructose, that is why, it is a fructosan
b. Found in Tubers, and roots of Dahlias Artichokes, and dandelions.
c. Uses →for Estimation of GFR and ECF.
4. Dextrins → Formed in the course of hydrolytic breakdown of starch.
5. Cellulose: -
a. Chief constituent of the frame work of plants.
b. Not digested by mammals (human) because of the absence of a hydrolase that attack the β-linkage
c. Important source of Bulk in diet.
6. Chitin →
a. Important structural polysaccharides of invertebrates (crustaceans and insects)
b. Consists of N-Acetyl — D — glycosamine units joined by β(1→4) glucosidic linkages.
7. GAG (mucopolysaccharides):
a. consists of = carbohydrates + Amino sugar + Uronic acid
b. GAG + proteins = proteoglycans.
eg. Hyaluronic acid, chondroitin sulfate and heparin.
8. Pectin → A purified carbohydrate obtained from peel of citrus fruit or from Apple pulp.