Evaluation of the Leaf of Cassia Podocarpa for Laxative Activity.
A literature review of the germs Cassia with emphasis on those cultivated in Nigeria is presented. General chemical screening of the leaves of Cassia species collected from Ile-Ife: C. alata L., C. hirsuta L., C. occidentalis L., C, podocarpa Guill. and Perr., C. siamea Lam. and C. tore. L., revealed the absence of anthraquinone except for C. podocarpa and C. alata. Detailed biological evaluation for laxative properties was carried out on C. podocarpa and C.acutifolia Delile (Senna; the herb-tee of commerce) the latter representing the reference drug. A dose--dependent relationship (linear above 200mg/kg) was established using the infusion of the leaves of C. podocarpa and C. acutifolia at a dose range of 100mg/kg - 700mg/kg of rat with the presence of wet faeces as an indication of laxation. The results were analysed statistically using student's t-test and analysis of variance which showed that there was no significant difference between the laxative activities of both Cassia species. The laxative activity of C. podocarpa was compared with that of C. acutifolia by using either "Biological Senna Equivalent (BSE)" or the "Percentage Senna Activity (PSA)" as established by this work. Thus, C. podocarpa was found to be a good substitute for Senna. This measurement representing an index of laxative activity, may also be applicable to any other Cassia species suspected to possess laxative actions.