Multifunctional oxidosqualene cyclase producing delta-amyrin (48%), alpha-amyrin (18%), beta-amyrin (13%) and 4 other minor triterpenes. (S)-2,3-epoxysqualene = delta-amyrin (S)-2,3-epoxysqualene = beta-amyrin (S)-2,3-epoxysqualene = alpha-amyrin Expressed in the leaves and in the epidermal cells but not in the inner tissues of the fruit. Belongs to the terpene cyclase/mutase family.