1.Solvent selection and optimization of α-chymotrypsin-catalyzed synthesis of N-Ac-Phe-Tyr-NH2 using mixture design and response surface methodology.
Hu SH1, Kuo CH, Chang CM, Liu YC, Chiang WD, Shieh CJ. Biotechnol Prog. 2012 Nov-Dec;28(6):1443-9. doi: 10.1002/btpr.1623. Epub 2012 Oct 18.
A peptide, N-Ac-Phe-Tyr-NH(2) , with angiotensin I-converting enzyme (ACE) inhibitor activity was synthesized by an α-chymotrypsin-catalyzed condensation reaction of N-acetyl phenylalanine ethyl ester (N-Ac-Phe-OEt) and tyrosinamide (Tyr-NH(2) ). Three kinds of solvents: a Tris-HCl buffer (80 mM, pH 9.0), dimethylsulfoxide (DMSO), and acetonitrile were employed in this study. The optimum reaction solvent component was determined by simplex centroid mixture design. The synthesis efficiency was enhanced in an organic-aqueous solvent (Tris-HCl buffer: DMSO: acetonitrile = 2:1:1) in which 73.55% of the yield of N-Ac-Phe-Tyr-NH(2) could be achieved. Furthermore, the effect of reaction parameters on the yield was evaluated by response surface methodology (RSM) using a central composite rotatable design (CCRD). Based on a ridge max analysis, the optimum condition for this peptide synthesis included a reaction time of 7.4 min, a reaction temperature of 28.