Enzyme of the diterpenoid metabolism involved in the biosynthesis of antibacterial oryzalides such as phytocassane. Can use ent-cassadiene as substrate, but not C11-alpha-hydroxy-ent-cassadiene, ent-pimaradiene, ent-sandaracopimaradiene, ent-kaurene, ent-isokaurene, syn-pimaradiene, syn-stemarene, syn-stemodene. ent-cassa-12,15-diene + O2 + reduced [NADPH--hemoprotein reductase] = ent-11beta-hydroxycassa-12,15-diene + H(+) + H2O + oxidized [NADPH--hemoprotein reductase] Up-regulated by methyl jasmonate. Belongs to the cytochrome P450 family.