Powdered senna leaves and a commercial methanolic senna leaf extract were investigated
for apparent degradation pathways of known constituents. Different defined storage
conditions were chosen according to the guidelines of the international conference
on harmonization. Analytical fingerprinting was carried out by HPLC with photodiode
array detection. Differences in degradation pathways were observed between the powdered
herbal drug material and the extract, depending on storage conditions and packaging
materials. Within the crude plant material sennosides were shown to be degraded to
sennidine monoglycosides, while rhein 8-O-glucoside was hydrolysed to rhein by enzymatic processes. Degradation of the anthranoid
compounds was not due to the same pathways in the investigated commercial extracts.
Only unspecific alterations of all compounds were observed. Forced decomposition of
this herbal drug preparation under high temperature caused oxidative decomposition
of the sennosides to rhein 8-O-glucoside. Furthermore flavonoid glycosides decomposition were observed with an apparent
increase in the content of flavone aglyca.
Stability control - sennosides - degradation pathways -
Cassia senna
- Leguminosae - ICH guidelines
