 Nopaline ("N"2-(D-1,3-dicarboxypropyl)-L-arginine) was first isolated from crown gall tumors.It is the head member of the nopaline family of opines.It was also found in certain nontransformed plant tissues as a result of arginine metabolism

Nopalinic acid (also named ornaline) ("N"2-(D-1,3-dicarboxypropyl)-L-ornithine) is a member of the nopaline family found in crown gall tumors.