Effect of isoquinoline alkaloids on soybean lipoxygenase activity in vitro

Novel isoquinoline alkaloids were evaluated for their effect on the kinetics of a soybean lipoxygenase type I using linoleic acid as substrate. Some of these alkaloids were found to increase the initial reaction velocity, this property seems related to phenolic groups present in the molecule. The effect of these compounds on the soybean lipoxygenase activity was compared to that of others products which are known to affect this reaction. A reaction mechanism is then proposed: it appeared, in this reaction a correlative structure-activity of phenolic compounds we tested.