Catalyzed synthesis of hexyl acetate in immobilized lipase bioreactor

To efficiently improve lipase- catalyzed synthesis of food additive hexyl acetate in nonaqueous phase,a simple bioreactor was prepared by immobilizing Pseudomonas cepacia lipase on inner wall of conical flask via physical adsorption and with carboxymethyl cellulose as stabilizer,and used in catalyzed synthesis of hexyl acetate.Results showed that the reaction began after hexanol and vinyl acetate added in this reactor at 37℃ and150 r / min,and the reaction stopped once reaction mixture powered off it. Comparing with lipase power,the immobilized lipase in bioreactor could cause 7- fold increase in transesterification conversion rate of hexanol reacting with vinyl acetate after 7h.After 48 h,the conversion achieved more than 99%. Moreover,stability of lipase also was obviously strengthened for CMC- stabilized immobilization.After ten times of catalyzed recycles,total ten days of contacting with organic phase,CMC- stabilized immobilized lipase still kept 52% of transesterification activity.And under the same of conditions,water- modified immobilized lipase only left 12.8% of transesterification activity.It was obvious that the reactor was not only easy in operation but also available in enhancement of enzymatic activity and stability,fitting in nonaqueous catalysis.