Aloe Emodin
Aloe emodin is an anthraquinone which can be found in aloe vera and buckthorn. Aloe emodin, when ingested, will irritate the intestine and cause rapid bowel movements. Isolated from the seed of buckthorn, aloe emodin has an extreme inhibitory effect on a certain type of leukemia in mice.
References
Leung, Albert Y. 1980. Encyclopedia of Common Natural Ingredient used in Food, Drugs and Cosmetics. John Wiley and Sons, N Y. 409 pp.
Weiner, Michael and A. Janet Weiner. 1980. Weiner's Herbal The Guide to Herb Medicine. Stein and Day, New York. 224 pp.