Page 130 - phytochemistry I - PharmD Clinical
P. 130
Amygdalase enzyme uses amygdalin (primary glycoside) to produce
prunasin and D-glucose. While, prunase enzyme uses prunasin
(secondary glycoside) to produce D-glucose and mandelonitrile.
Amygdalase Glucose + Prunasin Prunase Glucose + Benzaldehyde + HCN
O CH-CN Prunase Gentiobiose + Benzaldehyde + HCN
C6H10O4
O Emulsin or 2 Glucose + Benzaldehyde + HCN
C6H11O5
Acid
Amygdalin
Test for cyanogenic glycosides (Guignard,s test):
HCN liberated on hydrolysis can be determined by a simple color test
using sodium picrate (yellow) which turns brick-red (sodium
isopurpurate) in contact with HCN.
Thioglycosides
These are Sulphur-containing glycosides or glucosinolates. They mainly
occur in members of family Cruciferae.
۱۲۸
