September 2016 SPDS Book

Background

Definition: • The major polysaccharide in aloe is glucomannan  h h d f ( ) d l w ic is consiste o mannose major an g ucose  (minor) with 1,4‐β‐linked backbone.   • The mannose moieties are highly acetylated and are  referred to Acemannan in literature. 

2/3/6-OAc

2/3/6-OAc

6

HO

HO

HOH 2 C O

HOH 2 C

O

HOH 2 C

O

O

1

3 4 5

O

O

O

Structure of the major aloe polysaccharides

HO

2

HO

HO

OH

Glc p

Man p

y

x

Man p

z

Background

Definition ( cont’d ): • The molecular weight (MW) of aloe polysaccharides can be in  th f 10 000 2 000 000 D lt e range o , ‐ , ,  a ons: – Unprocessed fresh aloe polysaccharides usually has the  MW around  or over 2 million Daltons; – Less processed commercial aloe polysaccharide MW can be in the  range of 200,000‐500,000 Daltons; – Highly processed commercial aloe products contain aloe  polysaccharide MW can be lower to 10,000‐100,000 Daltons; • Degrees of acetylation on the aloe polysaccharides are varied  depending on process; • High MW polysaccharides may affect the accuracy of results  due to the effect of solubility and viscosity, etc.