Simultaneous separation of three isomeric sennosides from senna leaf (Cassia acutifolia) using counter‐current chromatography

Abstract

Senna leaf is widely consumed as tea to treat constipation or to aid in weight loss. Sennoside A, A1 , and B are dirheinanthrone glucosides that are abundant and the bioactive constituents in the plant. They are isomers that refer to the (R*R*), (S*S*), and (R*S*) forms of protons on C-10 and C-10' centers and it is difficult to refine them individually due to their structural similarities. The new separation method using counter-current chromatography successfully purified sennoside A, A1 , and B from senna leaf (Cassia acutifolia) while reversed-phase medium-pressure liquid chromatography yielded sennoside A only. n-Butanol/isopropanol/water (5:1:6, v/v/v) was selected as the solvent system for counter-current chromatography operation, and the partition coefficients were carefully determined by adding different concentrations of formic acid. High-resolution mass spectrometry and NMR spectroscopy were performed to verify the chemical properties of the compounds.

Determination of Total Sennosides and Sennosides A, B, and A1 in Senna Leaflets, Pods, and Tablets by Two-Dimensional qNMR

“…In DMSO- d 6 , which is one of the most suitable qNMR solvents for plant extracts, positions 10 and 10’ show proton shift values of around 5 ppm in DMSO and are thus in the range of anomeric sugar protons [ 8 ]. Because of the possible overlap of the H-10 and H-10’ signals with the anomeric sugar signals of sennosides or other molecules contained in the extract, development of a 1D qHNMR method was not taken into account.…”

“…Sennosides A and B (and A 1 ) are the main purgative agents, which are reduced to rhein anthrone in the human intestine [ 5 ]. Sennosides are considered among the most important pharmaceutical products of plant origin [ 6 ], a fact that is also reflected by methods and patents reporting their preparation and isolation from natural sources [ 7 , 8 ]. Sennosides A, B, and A 1 are homodimeric hydroxyanthracene diglycosides, linking two rhein 8-glucoside molecules in position 10, while sennosides C, D, and D 1 are heterodimers, consisting of one molecule of rhein 8-glucoside and one molecule of aloin 8-glucoside ( Figure 1 ).…”

A Review of Recent Studies on the Antioxidant and Anti-Infectious Properties of Senna Plants

“…Additionally, S. alexandrina is used in case of bowel irritable colon, as a pretreatment before diagnostic tests like colonoscopy [254] and as a supplement for weight reduction [255]. While the treatment with active compounds from genus Senna is widely used in different laxative drugs taken orally in liquid or solid dosage forms, in the form of instant tea and herbal tea, however, there are controversies in their usage.…”