The biological assay of vegetable purgatives.

Abstract

Summary 1 A method for the biological assay of vegetable purgatives based on the number of wet faeces produced by groups of mice after dosing is described. 2 The relation of the number of wet faeces per kg. of mouse to the logarithm of the dose was found to be linear. 3 40 mice divided equally into 4 groups were used in each assay.*** 2 groups received the standard preparation and the other 2 groups received the test preparation. The standard deviation of a single determination based on 9 such assays was estimated to be 15m7 per cent. The limits of error (P = 0m99) for a single assay are 100±40m5 per cent. 4 A special cage has been designed for this assay, and it has been found advantageous to incorporate a definite proportion of water in the diet, during test. 5 The method described is not only convenient in use but also gives a comparatively high degree of accuracy. 6 The method has been successfully applied to senna leaf, senna fruit and extracts and commercial preparations made from these drugs, pure glycosides (sennosides A and B), and pure anthracene compounds (aloe-emodin and aloe-emodin anthranol).