obsolete 1-18:2-2-18:3-digalactosyldiacylglycerol desaturase activity (obsolete GO:0102849)
OBSOLETE. Catalysis of the reaction: 1-18:2-2-18:3-digalactosyldiacylglycerol + O2 + a reduced electron acceptor = 1-18:3-2-18:3-digalactosyldiacylglycerol + 2 H2O + an oxidized electron acceptor.