The Study On Synthesization Of 7-ADCA And Dynamics

7-aminodesacetoxy cephalosproanic acid (7-ADCA) is an important intermediate of cephalosporin, cefalexin , cefradine , cefadroxil are synthesized from it. The amount of these cephalosporins are used is very abundant in the market, so increase of- yield , decrease of cost are indispensable to the medicament. In the paper, the optimal condition of reaction and all kinds of kinetic parameters are investigated; at the same time, we try to apply the fluidized bed reactor and the fixed-bed reactor to synthesize 7-ADCA in order to decrease damnification of the IMPA in the reaction.In the first place, the optimal condition of reaction and all kinds of kinetic parameters are investigated. It is indicated that the optimal pH and temperature were 8.0 and 333K for hydrolytic reaction of Cep G by immobilized penicillin acylase, respectively. The immobilized enzyme was stable at temperature 309K and in the" pH range of 6.0-11.0. The Michaelis-Menton constant, the maximum reaction rate and the inhibition constant of substrate in the stirred reactor were 9.6503mmol/L, 0.9024mmol/min-L, 256.2mmol/L, respectively at temperature 31 OK and pH 8.0. In the two kinds of hydrolytic products, 7-ADCA is non-competitive inhibitor and phenylacetic acid (PAA) is competitive inhibitor. In this experiment, the effect of 7-ADCA on the activities of IMPA is weak, so it is believed that PAA is the major inhibitor. At the same time, the catalyzing mechanism of acylase immobilized penicillin is mentioned in the paper, too. It is indicated that the mechanism relates with three-dimensional configuration of the enzyme and special domino offect...