THE SEPARATION AND STUDY OF THE BIOLOGICAL ACTIVITY OF GLYCAN OF SONCHUS OLERACEUS L. HERB FAMILY ASTERACEAE

The wide biological and therapeutic applications of Asteraceae
family motivated our attention to search on plant related to this
family in our local flora. So, Sonchus oleraceus L. was the chosen
plant.
The monomeric composition of the partially and completely
hydrolysates of S. oleraceus L. herb crude polysaccharide complex
was determined using GC/MS analysis. The obtained results
revealed the presence of mannose, xylose, arabinose, glucose,
galactose and glucuronic acid.
To determine the polymeric composition of the polysaccharide
complex, different methods of fractionation were used.
Demineralization was done first, then saponification. The
demineralized glycan was chromatographed on DEAE-cellulose
column. Elution being monitored spectrophotometrically using
phenol-sulphuric acid reagent. The result revealed that the
demineralized glycan composed of 1 major polymer. Both acidic
and neutral monomers of the partially hydrolysed fractions were
subjected to silylation and GC/MS analysis which provide
qualitative and quantitative determination of the monomeric
composition of each fraction. The polysaccharide complex was an
acidic heterogenous polysaccharide.
The crude glycan of S. oleraceus L. herb showed significant
anti-inflammatory effect and powerful hepatoprotective action
against CCl4 induced hepatotoxicity in rats. Further investigation
of hepatoprotective effect of demineralized, fraction I and fraction
II glycans were done and the results were compared with that of the
crude glycan. All of these glycans had powerful hepatoprotective
action against CCl4 induced hepatotoxicity. Fraction I glycan
(containing glucuronic acid) had the highest hepatoprotective
activity.