PIGMENT COOXIDATION ACTIVITY BY CHICKPEA LIPOXYGENASES

Two lipoxygenase isozymes present in chickpea, CL-1 and CL-2, show coo xidation properties for beta-carotene and retinyl acetate, with a high er activity for CL-1. Neither of them produces chlorophyll bleaching. Linoleic acid is necessary for the cooxidation reaction to take place. Besides pigment bleaching, CL-1 produces hydroperoxydienes and oxodie nes, and CL-2 practically only hydroperoxydienes. No synergic effect o f the two isozymes for the cooxidation activity was observed. CL-1 and CL-2 enzymatic activities are affected by beta-carotene concentration , with total inactivation at concentration values equal to or higher t han 14.0 mu M.