Sennosides along with other anthraquinone like hydroxyanthracene glycosides are the derivatives of Senna leaves. In the traditional & modern routine of medicines they have been used as proven laxatives in a natural way.

Origin
Native of Sudan and Arabia. Completely naturalized in Indian agro climatic conditions and is cultivated in southern India, Rajasthan, Gujarat and Kutch in western India. 

Morphology
The stem is erect, smooth, and pale green. It has long, spreading branches, bearing leaflets in four or five pairs, averaging an inch long. It is lanceolate or obviate, unequally oblique at the base, veins distinct on the under surface, brittle, greyish-green, of a faint, peculiar odour, and mucilaginous, sweetish taste. The form of the base, and freedom from bitterness, distinguish the Senna from the Argil leaves, which are also thicker and stiffer. The flowers are small and yellow. The pods are broadly oblong; about 2 inches long by 7/8 inch broad, and contain about six seeds.

Senna preparations
Commercial Senna is prepared for use by garbling, or picking out the leaflets and rejecting the lead-stalks, impurities, and leaves of other plants. Good Senna may be known by the bright, fresh, yellowish green colour of the leaves, with a faint and peculiar odour rather like green tea, and a mucilaginous, sweetish, slightly bitter taste. It should be powdered only as wanted, because the powder absorbs moisture, becomes mouldy, and loses its value. Boiling destroys its virtues, unless it is in vacuum, or in a covered vessel.