Oil used externally for dermatitis and eye ailments. Leaves applied to the head to relieve headache and as a poultice for boils. The castor oil consists principally of ricinoleic acid with only small amounts of dihydroxystearic, linoleic, oleic, and stearic acids. The unsaponifiable matter contains b -sitosterol. The seeds contain a powerful lipase, employed for commercial hydrolysis of fats, also amylase, invertase, maltase, endotrypsin, glycolic acid, oxidase, ribonuclease, and a fat-soluble zymogen.
Sprouting seeds contain catalase, peroxidase and reductase.
The principal toxin is the albumin, ricin. However, it produces antigenic or immunizing activity, producing in small doses an antitoxin analagous to that produced against bacteria. High humidity contributes to the development of diseases. Cultivation Castor is propagated entirely by seed treated to resist disease. Castor exhausts the soil quickly.