1117-55-1Relevant articles and documents
Synthetic application and activity of cutinase in an aqueous, miniemulsion model system: Hexyl octanoate synthesis
De Barros, Dragana P.C.,Fernandes, Pedro,Cabral, Joaquim M.S.,Fonseca, Luis P.
, p. 95 - 102 (2011)
Cutinase has been shown to be a promising biocatalyst for applications in processes targeted for industrial scale. This work aims to further contribute for highlighting such role, by bestowing detailed insight on the application of cutinase for the synthesis of value added compounds in miniemulsion environments (oil-in-water). The synthesis of hexyl octanoate was used as model system, due to the relevance of this compound for industrial applications as flavor and fragrance agent. The nature, specificity and selectivity of the catalyst enable operation under mild reaction conditions, without undesirable side reactions, leading to a very pure product. A high conversion yield, about 86%, for an enzyme concentration of 5 mg ml-1, was achieved. Hexyl octanoate synthesis and cutinase activity for different acid: alcohol molar ratio (R), under different pH environments, were evaluated. A maximum cutinase activity of 2.20 μmol mg-1 min-1 was observed for R = 0.5, which was tentatively ascribed to the stabilizing effect of hexanol on the miniemulsion. It is thus considered that the accumulation of the hydrophobic hexyl octanoate inside the droplets stabilize the miniemulsion system.
Organometallic substrates of enzymes: lipase catalysed transesterifications in organic solvents via O-stannyl ethers
Therisod, Michel
, p. C8 - C10 (1989)
Lipases from pig pancreas and from Chromobacterium viscosum (but not from Candida cylindracea) catalyze transesterification reactions between ethyl esters of carboxylic acids and tributylstannyl ethers of primary and secondary alcohols.At concentrations 1M or higher in anhydrous hydrocarbons, use of these nucleophilic derivatives of alcohols gives reaction rates ca. three times higher than those for the corresponding alcohols.
Kinetic study on the enzymatic esterification of octanoic acid and hexanol by immobilized Candida antarctica lipase B
Lopresto, Catia Giovanna,Calabr, Vincenza,Woodley, John M.,Tufvesson, P?r
, p. 64 - 71 (2014)
This study investigates reaction kinetics of the esterification of octanoic acid and hexanol into hexyloctanoate, catalyzed by an immobilized Candida antarctica lipase (Novozym435). The product is consid-ered natural and used as a fresh vegetable and fruity flavour additive in food, cosmetic and pharmaceuticalproducts. The reaction is performed in n-decane as the solvent, to improve enzyme stability and toincrease the reaction yield. The influence of substrate concentration on hexyl octanoate synthesis isinvestigated over a wide range up to 2 M. The observed bi-substrate inhibition pattern follows a Ping-Pong bi-bi mechanism with dead-end inhibition by both substrates and, based on the proposed model, thekinetic constants of the esterification reaction are estimated. These parameters are verified to be intrin-sic neither external nor internal mass transfer resistances are significant for the examined reactionsystem and are essential to extend analysis to a large-scale process and for a wide range of operatingconditions. The progress of the reaction is also observed and the kinetic model is validated by fittingexperimental progress curves with two different concentrations of biocatalyst. Effects of biphasicity ofthe reaction system, inhibition by the ester produced and the influence of the reverse reaction have beenalso evaluated.
Second-Generation meta-Phenolsulfonic Acid-Formaldehyde Resin as a Catalyst for Continuous-Flow Esterification
Hu, Hao,Ota, Hajime,Baek, Heeyoel,Shinohara, Kenta,Mase, Toshiaki,Uozumi, Yasuhiro,Yamada, Yoichi M. A.
supporting information, p. 160 - 163 (2020/01/02)
A second-generation m-phenolsulfonic acid-formaldehyde resin (PAFR II) catalyst was prepared by condensation polymerization of sodium m-phenolsulfonate and paraformaldehyde in an aqueous H2SO4 solution. This reusable, robust acid resin catalyst was improved in both catalytic activity and stability, maintaining the characteristics of the previous generation catalyst (p-phenolsulfonic acid-formaldehyde resin). PAFR II was applied in the batchwise and continuous-flow direct esterification without water removal and provided higher product yields in continuous-flow esterification than any other commercial ion-exchanged acid catalyst tested.
