The method of Yegnanarayan and Shrotri (1982) was followed.
All the mice were screened initially by giving 1.0 ml
of castor oil orally and only those showing diarrhoea were
selected for further study. Extract pre-treatment (100, 250 and
500 mg/kg) was given orally 1 h before the mice were administered
with the standard dose of 1.0 ml of castor oil. The animals
were caged individually; the latent period was noted and examined
hourly for the presence of diarrhoea 6 h after the castor oil
challenge. Diarrhoea was defined as the presence in the stool
of fluidy material, which stained the absorbent paper placed
beneath the cage. The number of respondents and the number of
stools passed during the 6-h period were noted for each mouse.
Purging index (PI) was calculated as follows: