REACTION OF EGG-WHITE WITH 5-5'-DITHIOBIS (2-NITROBENZOIC ACID)

Egg white diluted approximately 1:1 with 0.2M phosphate buffer pH 8 reacted with 5-5''-dithiobis (2-nitrobenzoic acid) to produce yellow color. The reaction time course was divided into a fast and slow reaction and analysed by 2nd order kinetic equations. Rate constants of 0.370 .+-. 0.0276 M-1sec-1 and 0.179 .+-. 0.00785 M-1 s-1 were obtained for the fast and slow reactions, respectively, in 0.1M PO4, pH 8, 30 C. Ranges are standard derivations. The effect of pH, temperature and ionic strength were studied. A pK = 8.3 was obtained for the reacting group and an activation energy of 10.7 Kcal/mol was obtained for the reaction. Increasing ionic strength increased reactivity slightly. The component giving the reaction was non-dialyzable, probably a protein, and was neither a globulin nor ovalbumin.