Abstract
Optical active D-amino acid－D-p-hydroxyphenyl-glycine(D-HPG) is one effecitve composite of antibiotics such as aspoxicillin，cefbuperazone. Because of its high profit and increasing marketing, it's gradually an urgency to produce D-HPG economically.D-hydantoinase decomposites DL-p-HPH to N-carbamoyl-D-p-hydroxyphenyl-glycine－D-NCHPG and we obtain D-HPG from hydrolyzation of D-NCHPG with nitrous acid after getting rid of ammonium ion and carbon dioxide.As a result of quick development of gene engineering technology,we're supposed to transfer wild type D-hydantoinase gene to gene recombinant E.coli easily for expressing high activity D-hydantoinase abundantly. And the following research work should focus on how to immobilize this enzyme,prolong its recycling batches and economize costs of cell culture and enzyme purification.In this study,we choose several kinds of anion ion exchanger resin to adsorp D-hydantoinase, test its physical and chemical stability and finally get a proper support for our sequent investigation of comparison of D-hydantoinase before and after immobilization.In the last,we try to design a pratical bio-reactor for a high concentration repeat batches usage.After a lot of experiment tests,we find DEAE-Sepharose CL-6B has more excellent adsorption property,thermo stability,mechanical stability and chemical stabilty than other support and D-hydantoinase immobilized by which maintains certain activity in broader pH and temperature range than native one.When we process high concentration repeat batches study in an adequate reactor,it's observed that no obvious activity loss after 14 repeated batches use and get D-NCHPG more than 30g/l a day which is a much better result than any reviewed literature.And we verify this immobilized system with high stabilty and activity is adequate for D-NCHPG manufacture procedure nowaday.