Preparation of gemini-type amphiphiles bearing cyclitol head groups and their application as high-performance modifiers for lipases

摘要

Five gemini-type amphiphiles bearing cyclitol head groups,which have abundance of axial hydroxy groups,are newly synthesized.The syntheses are based on a common mixed anhydride method utilizing N,N'-[iminobis(trimethylene)]bisquinamide,prepared from iminobispropylamine and quino-1,5-lactone,and dialkyl N-(3-carboxypropanoyl)-L-glutamates as polar and hydrophobic components,respectively.Candida rugosa lipase (CRL) and Pseudomonas cepacia lipase (PCL) are co-lyophilized with these synthesized gemini-type amphiphiles,and their transesterification activities in organic solvents are evaluated.The modified PCL and CRL prepared by using each amphiphile showed highly enhanced and moderately enhanced enzyme activity,respectively.These results are discussed in terms of the increased preferential exclusion of the hydrophilic heads of the amphiphile and of the topological view of the amphiphile.