title: Enzymatic ester synthesis with continuous measurement of water activity.
abstract: Ester synthesis from aliphatic monoalcohols and organic acids was investigated by using a microbial lipase. The reaction medium only contained the substrates and the enzyme without addition of water or organic solvent. During the reaction, water was produced and the water activity (aw) increased. Batch reactors and continuous-flow reactors were used. In batch, the aw was 0.13 at the beginning of the reaction and increased to reach a plateau at 0.77, after which ester synthesis continued without modification of the aw. Different alcohols and acids were tried in solid-liquid reactors, and all cases synthesis occurred, leading to a significant increase in the water activity. For continuous-flow reactors, the use of silica beads retaining water inside the reactor where the enzymatic reaction took place resulted in some control of the enzymatic reaction by changing the aw.
authors.affiliation: Laboratoire de Technologie Enzymatique, Université de Compiègne, France.
authors.forename: M
authors.initials: M
authors.lastname: Goldberg
authors.forename: F
authors.initials: F
authors.lastname: Parvaresh
authors.forename: D
authors.initials: D
authors.lastname: Thomas
authors.forename: M D
authors.initials: MD
authors.lastname: Legoy
mesh_terms: D000438:Alcohols / Q000378:metabolism; D002175:Candida / Q000201:enzymology; D002264:Carboxylic Acids; D003652:Decanoic Acids / Q000378:metabolism; D004951:Esterification; D004952:Esters; D007850:Lauric Acids / Q000378:metabolism; D008049:Lipase / Q000378:metabolism*; D019301:Oleic Acid; D009829:Oleic Acids / Q000378:metabolism; D014867:Water / Q000378:metabolism*
chemical_list: D000438:Alcohols; D002264:Carboxylic Acids; D003652:Decanoic Acids; D004952:Esters; D007850:Lauric Acids; D009829:Oleic Acids; D014867:Water; C030358:lauric acid; D019301:Oleic Acid; D008049:Lipase