aloin
A diastereoisomeric mixture of aloin A (barbaloin) and aloin B (isobarbaloin), which have similar properties. It is a bitter-tasting, yellow-brown colored compound found in the exudate of at least 68 Aloe species at levels of up to 6.6% of leaf dry weight (making between 3% and 35% of the total exudate), and in another 17 species at indeterminate levels. It is used as a stimulant-laxative, treating constipation by inducing bowel movements.