Ethyl acetate production by immobilized esterases from spore -forming microorganisms

LOTO FLAVIA; ROMERO C; BAIGORI M.D; PERA, LICIA M

Rosario. Santa Fe, Argentina.

Congreso; SAIB 42 th Annual Meeting. XLII Reunión Anual; 2006

Sociedad Argentina de Investigación en Bioquímica y Biología Molecular

Introduction: Ethyl acetate (EAc) is an important raw material for many applications in chemical industry including coatings, adhesives, perfumes, and plasticizers. Enzymatic biotransformation has the advantage of high specificity and much simpler processes in comparison to chemical synthesis and various resolving agents. The aim of this work was to evaluate the production of EAc using immobilized esterases from sporeforming microorganisms. Methods: Standard Bacillus subtilisBacillus subtilis (168) and spore-forming microorganisms isolated from different sources (A14, A55, A60, A62, M2) were used throughout this study. Microorganisms were grown in LB at 37 °C. Both cells harvested by centrifugation and polyacrylamide gel–entrapped supernatant were used as source of enzyme. Esterifications were performed during 24h in n-hexane using acetic acid and ethanol as substrates. Ester synthesis was determined by acid titration with NaOH. Qualitative analyses of EAc were done by thin layer chromatography using chloroform as developing solvent. Result and Conclusion: Good productions of EAc in all systems assayed were observed. The highest yield was obtained with the polyacrylamide gel–entrapped supernatant from the isolation M2 showing a conversion of 93 %. This result indicates that gel entrapment method offers a good way for ester synthesis. This work was supported by grants PIP 6062 and PIP 6203.