Process Development for Benzyl Alcohol Production by Whole-Cell Biocatalysis in Stirred and Packed Bed Reactors
The ocean is an excellent source for new biocatalysts due to the tremendous genetic diversity of marine microorganisms, and it may contribute to the development of sustainable industrial processes. A marine bacterium was isolated and selected for the conversion of benzaldehyde to benzyl alcohol, whi...
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MDPI AG
2022-05-01
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Online Access: | https://www.mdpi.com/2076-2607/10/5/966 |
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author | Carlos J. C. Rodrigues Carla C. C. R. de Carvalho |
author_facet | Carlos J. C. Rodrigues Carla C. C. R. de Carvalho |
author_sort | Carlos J. C. Rodrigues |
collection | DOAJ |
description | The ocean is an excellent source for new biocatalysts due to the tremendous genetic diversity of marine microorganisms, and it may contribute to the development of sustainable industrial processes. A marine bacterium was isolated and selected for the conversion of benzaldehyde to benzyl alcohol, which is an important chemical employed as a precursor for producing esters for cosmetics and other industries. Enzymatic production routes are of interest for sustainable processes. To overcome benzaldehyde low water solubility, DMSO was used as a biocompatible cosolvent up to a concentration of 10% (<i>v</i>/<i>v</i>). A two-phase system with <i>n</i>-hexane, <i>n</i>-heptane, or <i>n</i>-hexadecane as organic phase allowed at least a 44% higher relative conversion of benzaldehyde than the aqueous system, and allowed higher initial substrate concentrations. Cell performance decreased with increasing product concentration but immobilization of cells in alginate improved four-fold the robustness of the biocatalyst: free and immobilized cells were inhibited at concentrations of benzyl alcohol of 5 and 20 mM, respectively. Scaling up to a 100 mL stirred reactor, using a fed-batch approach, enabled a 1.5-fold increase in benzyl alcohol productivity when compared with batch mode. However, product accumulation in the reactor hindered the conversion. The use of a continuous flow reactor packed with immobilized cells enabled a 9.5-fold increase in productivity when compared with the fed-batch stirred reactor system. |
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language | English |
last_indexed | 2024-03-10T03:23:37Z |
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spelling | doaj.art-f4d4f31113374fbfb7f4a5a168923b472023-11-23T12:15:45ZengMDPI AGMicroorganisms2076-26072022-05-0110596610.3390/microorganisms10050966Process Development for Benzyl Alcohol Production by Whole-Cell Biocatalysis in Stirred and Packed Bed ReactorsCarlos J. C. Rodrigues0Carla C. C. R. de Carvalho1Department of Bioengineering, iBB—Institute for Bioengineering and Biosciences, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais, 1049-001 Lisbon, PortugalDepartment of Bioengineering, iBB—Institute for Bioengineering and Biosciences, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais, 1049-001 Lisbon, PortugalThe ocean is an excellent source for new biocatalysts due to the tremendous genetic diversity of marine microorganisms, and it may contribute to the development of sustainable industrial processes. A marine bacterium was isolated and selected for the conversion of benzaldehyde to benzyl alcohol, which is an important chemical employed as a precursor for producing esters for cosmetics and other industries. Enzymatic production routes are of interest for sustainable processes. To overcome benzaldehyde low water solubility, DMSO was used as a biocompatible cosolvent up to a concentration of 10% (<i>v</i>/<i>v</i>). A two-phase system with <i>n</i>-hexane, <i>n</i>-heptane, or <i>n</i>-hexadecane as organic phase allowed at least a 44% higher relative conversion of benzaldehyde than the aqueous system, and allowed higher initial substrate concentrations. Cell performance decreased with increasing product concentration but immobilization of cells in alginate improved four-fold the robustness of the biocatalyst: free and immobilized cells were inhibited at concentrations of benzyl alcohol of 5 and 20 mM, respectively. Scaling up to a 100 mL stirred reactor, using a fed-batch approach, enabled a 1.5-fold increase in benzyl alcohol productivity when compared with batch mode. However, product accumulation in the reactor hindered the conversion. The use of a continuous flow reactor packed with immobilized cells enabled a 9.5-fold increase in productivity when compared with the fed-batch stirred reactor system.https://www.mdpi.com/2076-2607/10/5/966biocatalysistwo-phase biocatalysisstirred tank reactorpacked bed reactorwhole cellsimmobilization |
spellingShingle | Carlos J. C. Rodrigues Carla C. C. R. de Carvalho Process Development for Benzyl Alcohol Production by Whole-Cell Biocatalysis in Stirred and Packed Bed Reactors Microorganisms biocatalysis two-phase biocatalysis stirred tank reactor packed bed reactor whole cells immobilization |
title | Process Development for Benzyl Alcohol Production by Whole-Cell Biocatalysis in Stirred and Packed Bed Reactors |
title_full | Process Development for Benzyl Alcohol Production by Whole-Cell Biocatalysis in Stirred and Packed Bed Reactors |
title_fullStr | Process Development for Benzyl Alcohol Production by Whole-Cell Biocatalysis in Stirred and Packed Bed Reactors |
title_full_unstemmed | Process Development for Benzyl Alcohol Production by Whole-Cell Biocatalysis in Stirred and Packed Bed Reactors |
title_short | Process Development for Benzyl Alcohol Production by Whole-Cell Biocatalysis in Stirred and Packed Bed Reactors |
title_sort | process development for benzyl alcohol production by whole cell biocatalysis in stirred and packed bed reactors |
topic | biocatalysis two-phase biocatalysis stirred tank reactor packed bed reactor whole cells immobilization |
url | https://www.mdpi.com/2076-2607/10/5/966 |
work_keys_str_mv | AT carlosjcrodrigues processdevelopmentforbenzylalcoholproductionbywholecellbiocatalysisinstirredandpackedbedreactors AT carlaccrdecarvalho processdevelopmentforbenzylalcoholproductionbywholecellbiocatalysisinstirredandpackedbedreactors |