Coprostanone is a metabolite of cholesterol. The conversion of cholesterol into coprostanol by intestinal microorganisms has been reported to occur by means of two different pathways. One pathway involves the intermediate formation of delta4-cholelestenone and coprostanone. In the other pathway, cholesterol is transformed into coprostanol by the direct reduction of the delta5 double bond. Coprostanone concentration is used as a fecal sterol biomarker in different investigations. For example, to determine of fecal sterols following a diet with and without plant sterols, to assess if faecal steroid excretion in humans is affected by calcium supplementation and other investigations.

Coptisine (COP), a protoberberine alkaloid, is widely found in Chinese medicinal plants (family Berberidaceae, Ranunculaceae and Papaveraceae). It is reported that COP has a wide range of pharmacological and biological activities, including antibacterial, hypoglycemic, anti-tumorigenic, and gastric-mucous membrane protection. Considerable attention has been focused on its activity against central nervous system disorders, such as improving the symptoms of Alzheimer’s disease and even preventing its onset, by exerting antidepressant effects as a potent type A monoamine oxidase inhibitor. Coptisine was found to be an efficient uncompetitive Indoleamine 2,3-dioxygenase inhibitor. Coptisine is a potent inhibitor of human organic cation transporters.