Morus alba, known as white mulberry, is a short-lived, fast-growing, small to medium sized mulberry tree, which grows to 10–20 m tall. The species is native to northern China, and is widely cultivated and naturalized elsewhere. Leaves extract of Morusalba exhibited inhibitory activities against α-glucosidase and tyrosinase. Bioactive constituents were isolated from extracts by bioassay-guided fractionation. One new stable and two pairs of new interconvertible flavanes were isolated. Possible scheme for the interconversion was illustrated. In traditional Chinese medicine, the fruit is used to treat prematurely grey hair, to "tonify" the blood, and treat constipation and diabetes. The bark is used to treat cough, wheezing, edema, and to promote urination. It is also used to treat fever, headache, red dry and sore eyes. The root bark of Morus alba (Moraceae) has been used as a traditional medicine in Asian countries.