Morphological, anatomical characterization and profiling of laxative principles sennosides in fifteen species from genus Cassia, Chamaecrista and Senna

Cassia, Chamaecrista, and Senna species are potential sources of laxative principle sennosides. About 45 species belonging to the family are reported from India. It is often essential to confirm the identity of official drug material as mentioned in the Pharmacopoeia. In the present investigation, 15 species were selected for morphological and anatomical characterization. Profiling of sennosides A and B in extracts of leaves of selected species was also carried out using a RP-HPLC method. Selected species could be differentiated on the basis of their habit, morphological and anatomical characters. S. alata, S. auriculata, S. polyphylla, S. surattensis are shrub or small tree whereas S. alexandrina, C. pumila, S. tora, C. mimosoides, C. absus, S. occidentalis, S. uniflora are herb and C. fistula, C. javanica, C. renigera and S. siamea are tree. These species can be differentiated by the shape of the leaflets, viz., oblong, obovate-oblong in S. alata, S. auriculata, C. javanica, S. surattensis, S. tora and S. uniflora; elliptic-lanceolate in S. alexandrina; ovate-elliptical in C. fistula; Ovate-lanceolate in S. occidentalis; oblong to suborbicular in Chamaecrista absus; oblong-elliptic in S. polyphylla and linear-oblong in Chamaecrista mimosoides and Chamaecrista pumila. The length of the petiole in the selected species was in the range of 0.1 to 0.9 mm. The length of the leaves also varied in these species such as the leaflets were very small in size in S. auriculata, Chamaecrista mimosoides, S. polyphylla and Chamaecrista pumila. Medium size leaflets were present in S. alexandrina, C. javanica, Chamaecrista absus, C. renigera, S. tora and S. uniflora. The leaflets size were comparatively larger in S. alata, S. occidentalis, C. fistula and S. surattensis. The weight of the leaves was directly proportional to the size of the leaves. The anatomical characterstics showed that C. fistula, S. polyphylla, Chamaecrista pumila, S. surattensis and S. siamea had amphicribal type of vascular bundle and xylem was surrounded by phloem whereas in S. alata, S. alexandrina, Chamaecrista absus, Chamaecrista mimosoides, S. auriculata, C. javanica, C. renigera, S. tora and S. uniflora had collateral type of vascular bundle in which phloem was towards abaxial side and xylem towards adaxial side. Based on the sennoside content, three species, i.e., S. tora, C. javanica and S. occidentalis could be considered as potential alternative sources of sennoside A and B.