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.

Aims: To examine the killing efficiency of UV KrCl excilamp against Gram‐positive and Gram‐negative bacteria. Methods and Results: Vegetative cells of Bacillus cereus, Bacillus subtilis, Escherichia coli O157:H7, Staphylococcus aureus and Streptococcus pyogenes at initial populations from 10² to 10⁷ colony‐forming units (CFU) ml⁻¹ were treated by KrCl excilamp in sterile Ringer’s solution with and without H₂O₂. The number of viable cells was determined using spread plating techniques and nutrient agar method with subsequent incubation at 28°C or 37°C for 24 h. At estimated populations of 10²–10⁵ CFU ml⁻¹E. coli O157:H7 and Staph. aureus were the most sensitive and showed 100% disinfection within 15 s (29·2 mJ cm⁻²). Bacillus subtilis was more sensitive to UV treatment than B. cereus. The UV/H₂O₂ inactivation rate coefficients within this population range were two times higher than those observed for UV treatment alone. No effect of H₂O₂ was observed at 10⁷ CFU ml⁻¹ for Bacillus sp. and Strep. pyogenes. Conclusions: The narrow‐band UV radiation at 222 nm was effective in the rapid disinfection of bacteria in aqueous suspensions. Significance and Impact of the Study: KrCl excilamps represent UV sources which can be applied for disinfection of drinking water in advanced oxidation processes.