Eriobotrya japonica leaf is included in the Chinese Pharmacopoeia and is widely used as a medicinal material in traditional treatment of a variety of chronic diseases in China and other East Asian countries. Phytochemical investigations showed that its main components are essential oil, triterpenes, sesquiterpenes, flavonoids, tannins, and megastigmane glycosides. Among them, triterpene acids are considered as the key pharmacological components. To date, more than twenty triterpene acids in Eriobotrya japonica leaf have been identified, including the major four triterpene acids, that is, ursonic acid, corosolic acid, oleanolic acid, and maslinic acid, which belong to ursane type and oleanane type.
In the 2020 Edition of the Chinese Pharmacopeia, two marker compounds, oleanolic acid and ursonic acid are assayed by using an HPLC-UV method, which is important for quality control of this traditional Chinese medicine (TCM).