Lipozyme 435-Mediated Synthesis of Xylose Oleate in Methyl Ethyl Ketone

Abstract

In this paper, we have performed the Lipozyme 435-catalyzed synthesis of xylose oleate in methyl ethyl ketone (MEK) from xylose and oleic acid. The effects of substrates’ molar ratios, reaction temperature, reaction time on esterification rates, and Lipozyme 435 reuse were studied. Results showed that an excess of oleic acid (xylose: oleic acid molar ratio of 1:5) significantly favored the reaction, yielding 98% of xylose conversion and 31% oleic acid conversion after 24 h-reaction (mainly to xylose mono- and dioleate, as confirmed by mass spectrometry). The highest Lipozyme 435 activities occurred between 55 and 70 °C. The predicted Ping Pong Bi Bi kinetic model fitted very well to the experimental data and there was no evidence of inhibitions in the range assessed. The reaction product was purified and presented an emulsion capacity close to that of a commercial sugar ester detergent. Finally, the repeated use of Lipozyme 435 showed a reduction in the reaction yields (by 48 and 19% in the xylose and oleic acid conversions, respectively), after ten 12 h-cycles.

Enzymatic Transesterification of Atlantic Salmon (Salmo salar) Oil with Isoamyl Alcohol

“…At the same amount of enzyme preparation, the reaction catalyzed by Lipozyme ® RM IM is almost three times faster than the reaction catalyzed by Lipozyme ® 435. Although C. antarctica lipase (Lipozyme ® 435) is widely used for biodiesel synthesis studies [ 31 ], unfortunately, in our case, this enzyme preparation was not very effective after 4 h. The transesterification degree was only 5.2 ± 0.45%; however, using R. miehei lipase (Lipozyme ® RM IM), a transesterification degree of 15.87 ± 0.18% was observed. Considering the fact that the enzyme preparation Lipozyme ® RM IM was the most effective for the alcoholysis reaction, so this lipase was selected for further studies.…”

Production of sugars from mixed hardwoods for use in the synthesis of sugar fatty acid esters catalyzed by immobilized‐stabilized derivatives of Candida antarctica lipase B

“…Excess water could force the reaction equilibrium towards hydrolysis instead of esterification. 36 Water also influences the activity and selectivity of the enzyme and may lead to its inhibition or inactivation. 48,49 For these reasons, we tried to keep the water at the lowest possible level (a minimal amount of water is necessary to ensure the hydration, stability, and catalytic activity of the enzyme).…”

“…Overall, the higher reduction in the xylose conversion after six 24 h batches with the uncoated N435 is likely due to the CALB desorption from the matrix of the commercial lipase, as discussed in our previous article. 36 In particular, residual oleic acid and/or SFAEs can lead to CALB desorption from the support due to their surfactant properties. Indeed, at the end of the reuse cycles, we identified a 56 ± 0.4% drop in the N435 hydrolytic activity (A H ) (see above) after incubation in a crude reaction product that also contained unconverted oleic acid, which confirmed N435 leakage from the matrix.…”

“…35 Despite the extensive use of this enzyme preparation, it is difficult to use it multiple times because of enzyme leaching from the support in the presence of substrates/products with surfactant properties. 36 The non-covalent bonds between lipase and the support are disrupted by the presence of fatty acids and/or SFAEs in the reaction medium, leading to lipase loss to the medium. 37 As an alternative, coating the N435 surface with polyethyleneimine (PEI) can promote physical intermolecular crosslinking, with the potential to prevent enzyme release while tailoring some of the biocatalyst properties (e.g.…”

Enzyme Immobilization

“…This modification permitted to employ the benefits of enzyme mineralization (changes in activity and enantiospecificity in these examples) [ 15 ] without the problems derived of the small size and fragile nature of nanoflowers [ 16 ]. Another paper uses the commercial immobilized lipase Lipozyme 435 to produce xylose oleate in methyl ethyl ketone from xylose and oleic acid [ 17 ]. The last paper, using only lipases, shows the enzymatic synthesis of ascorbyl palmitate catalyzed by the commercial immobilized lipases Amano Lipase PS, Lipozyme ® TL IM, Lipozyme ® Novo 40086, Lipozyme ® RM IM and Lipozyme ® 435, selecting Lipozyme ® 435 for further studies [ 18 ].…”