Psoralidin, a naturally occurring coumestan isolated from the fractions of organic solvents such as ethylacetate, hexane, or n-butanol of the seed extract of Psoralea corylifolia L., has a variety of biological activities such as anticancer, antioxidant, antibacterial, antidepressant, anti-inflammatory activities, and regulation of insulin signaling. It is an agonist for both estrogen receptor (ER)α and ERβ with binding affinities (IC50s) of 1.03 and 24.6 μM, respectively.