HYDROLYSIS OF D,L-TRYPTOPHAN ISOPROPYL ESTER CATALYZED BY BETA-CYCLODEXTRIN

beta-Cyclodextrin (BCD) catalysed hydrolysis of D,L-tryptophan isoprop yl ester is found to be pH dependent. The pH rate constant profiles sh ow that the k(obs) values for the BCD catalysed reactions are higher t han those of the control in the pH range 9.8 to 12.9. The reaction fol lows Michaelis-Menten type kinetics exhibiting substrate saturation. M ichaelis-Menten treatment results in determination of K-D (0.067 M) an d k(cat) (0.015 M(-1) min(-1)). A k(cat)/ k(un) values of 0.94 has bee n determined. Tryptophan, the hydrolysis product formed exhibited enan tiometric excess of 7.9 to 18.4% of the (-) antipode in reactions cata lysed by BCD, heptakis-2,6-di-O-methyl-beta-cyclodextrin (DM-BCD), BCD -epiclorohydrin polymer (BCD-polymer) and a 1:1 complex of Cu(II)-beta -cyclodextrin (Cu(II)-BCD).