Enzymatic synthesis of butyl acetate in a packed bed reactor under liquid and supercritical conditions

Esters in the Food and Cosmetic Industries: An Overview of the Reactors Used in Their Biocatalytic Synthesis

Esters are versatile compounds with a wide range of applications in various industries due to their unique properties and pleasant aromas. Conventionally, the manufacture of these compounds has relied on the chemical route. Nevertheless, this technique employs high temperatures and inorganic catalysts, resulting in undesired additional steps to purify the final product by removing solvent residues, which decreases environmental sustainability and energy efficiency. In accordance with the principles of "Green Chemistry" and the search for more environmentally friendly methods, a new alternative, the enzymatic route, has been introduced. This technique uses low temperatures and does not require the use of solvents, resulting in more environmentally friendly final products. Despite the large number of studies published on the biocatalytic synthesis of esters, little attention has been paid to the reactors used for it. Therefore, it is convenient to gather the scattered information regarding the type of reactor employed in these synthesis reactions, considering the industrial field in which the process is carried out. A comparison between the performance of the different reactor configurations will allow us to draw the appropriate conclusions regarding their suitability for each specific industrial application. This review addresses, for the first time, the above aspects, which will undoubtedly help with the correct industrial implementation of these processes.

Process intensification using immobilized enzymes for the development of white biotechnology

Process intensification of biocatalysed reactions using different techniques such as microwaves, ultrasound, hydrodynamic cavitation, ionic liquids, microreactors and flow chemistry in various industries is critically analysed and future directions provided.

Immobilization of a Cutinase from Fusarium oxysporum and Application in Pineapple Flavor Synthesis

In the present study, the immobilization of a cutinase from Fusarium oxysporum was carried out as cross-linked enzyme aggregates. Under optimal immobilization conditions, acetonitrile was selected as precipitant, utilizing 9.4 mg protein/mL and 10 mM glutaraldehyde as cross-linker. The immobilized cutinase (imFocut5a) was tested in isooctane for the synthesis of short-chain butyrate esters, displaying enhanced thermostability compared to the free enzyme. Pineapple flavor (butyl butyrate) synthesis was optimized, leading to a conversion yield of >99% after 6 h, with an initial reaction rate of 18.2 mmol/L/h. Optimal reaction conditions were found to be 50 °C, a vinyl butyrate/butanol molar ratio of 3:1, vinyl butyrate concentration of 100 mM, and enzyme loading of 11 U. Reusability studies of imFocut5a showed that after four consecutive runs, the reaction yield reaches 54% of the maximum. The efficient bioconversion offers a sustainable and environmentally friendly process for the production of "natural" aroma compounds essential for the food industry.