Biological Assay and Its Relation to Chemical Structure

The effect of raw material purity on the acute toxicity and laxative effect of sennosides

“…We found the sennoside extracts to be more potent laxatives than the pure sennoside. This is in agreement with earlier observations (Fairbairn 1976). and the relative potencies determined for sennoside A (69-84%) are close to the findings of 60-68% by Fairbairn (1965) and Fairbairn & Moss (1970).…”

Oxalated, Sulphated and Primary Glycosides

“…Glycosidal fractions of senna prac tically free from non-sennoside material also showed enhanced activity up to almost twice that of sennoside (e.g. Fairbairn, 1976), and finally at least one primary glycoside has been isolated in pure form and shown to be highly active (see above). Furthermore, all these glyco sidal preparations contain sennoside com pounds which are much more soluble in water at pH 2-3 than are the pure sennosides.…”

“…The final elutions were carried out with water, the eluates freeze dried and the yellow sub stances resulting were stored in a desiccator. The 'sennoside' content of the Ca and K precipitates and of the purified glycosides was determined using the European Pharmacopoeia method (1975); UVL spectra, ash and glucose content were also determined and the biological activity in mice estimated by a modified Lou method (Fairbairn, 1976). The results are shown in table 1.…”

Cascara ( Frangula purshiana Cooper)

“…6 Most primary glycosides in the bark extract of cascara are stable at pH 2; therefore, these compounds pass into the intestines with minimal degradation. 6 Most primary glycosides in the bark extract of cascara are stable at pH 2; therefore, these compounds pass into the intestines with minimal degradation.…”