Page 127 - Pharmacognosy 02-06203

Plasma substitute, haemostatic dressing.

Aloes ‫الصب ر‬

The concentrated and dried juice of the leaves of various Aloe species family
liliaceae. It contains not less than 28.0 per cent of hydroxyanthracene derivatives,
expressed as barbaloin.
There are two main types Barbados aloes and cape aloes.
Aloe juice is in the pericycle outside each vascular bundle, while Aloe gel at the
lower surface of the leaf.
The Aloe juice is prepared by cutting transversely near the base. The collected juice
is then boiled for concentration.

Constituents:
1. Anthracene derivatives,

• They are c-glycosides: barbaloin
• O-glycoside: aloinosides.
• Free aglycones: aloe-emodin, chrysophanol.
2. Resin, which have very potent action and removed by boiling to dissolve the
glycosides (aloin).
Aloin: Water-soluble yellow crystalline substance extracted from Barbados aloes.

Test for identity:
Bornträger test:
The aglycones give rose red color.
Modified Bornträger test:
Oxidative hydrolysis using FeCl3/HCl yield the free aglycones.

Uses:

125