A simple and rapid method enhancing of lipoxygenase-1 to lipoxygenase-2+lipoxygenase-3 isoenzyme activity ratio in soybean meal extracts

Lipoxygenase-2 and lipoxygenase-3 isoenzymes can be eliminated from soybean (Glycine max) meal extract by a simple selective heat treatment. The optimum conditions were: 70 °C, for 5 min at pH 5.2 with an ionic strength of 0.05. The activity ratio of lipoxygenase-1 to lipoxygenase-2 + lipoxygenase-3 was enhanced from 5 to about 21. The resulting enzyme can be used immediately for hydroperoxidation or frozen without loss of activity.