Page 22 - phytochemistry I - PharmD Clinical

 Dextran is a large, water-soluble polymer of glucose.

Source:
 It is formed by the action of transglucosylase enzyme system present in

bacterium Leuconostic mesenteroides on sucrose. The reaction can be
summarized in the following equation:

Primer Dextran

Chemical Composition
 Dextrans are long slender molecules with α-1,6 linkages and α -1,2; α -1,3

or α -1,4 branching, depending on the strain and species of bacteria
employed.
 The branching is believed to occur every five glucose units.

Uses and Clinical Pharmacology
 Dextran 40 (M.wt 40,000) is used as a plasma extender at 10%

concentration.

Cellulose and Cellulose Derivatives

Occurrence:
 It is the chief polysaccharide of plant cell walls. It is chemically resistant to

all chemicals elaborated by the cell.
 Apart from being a pharmaceutical necessity, cellulose represent the core

material in paper and clothes industry.
Chemical Composition:
 Celluloses are anhydrides of β-glucose, possibly existing as long chains

that are not branched, consisting of 100 to 200 β -glucose residues.
 The β- Linkage in cellulose is hydrolyzed only by the enzyme Emulsin

(present in certain microorganisms).

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