Details
| Original language | English |
|---|---|
| Pages (from-to) | 67-72 |
| Number of pages | 6 |
| Journal | Molecular Catalysis |
| Volume | 458 |
| Early online date | 24 Aug 2018 |
| Publication status | Published - Oct 2018 |
| Externally published | Yes |
Abstract
Deep eutectic solvents (DESs) based on (-)-menthol and fatty acids (octanoic, decanoic and dodecanoic acid) were investigated as reaction media for the lipase catalyzed esterification of the DES compounds itself to synthesize (-)-menthol fatty acid esters. The DES acts as reaction medium and substrate pool simultaneously without the need of adding any solvent. Candida rugosa lipase was active in the neat (-)-menthol:fatty acid DESs to synthesize (-)-menthol fatty acid esters. This example shows for the first time that a valuable product can be enzymatically produced using both components of a DES without any co-solvent. The addition of water to the DESs enhanced the reaction outcome likely due to interfacial activation of the enzyme. In biphasic reaction systems with an addition of 10 wt% of water to the DES phase, the conversion (7 d) of octanoic, decanoic and dodecanoic acid reached 50%, 83% and 71%, respectively. This corresponds to a batch productivity of 133 g L−1 d−1 (24 h) and a final (-)-menthyl dodecanoate concentration of 957 mM (7 d) in the (-)-menthol:dodecanoic acid DES. Closer investigation of this DES reaction system revealed that water addition and stirring speed are interacting parameters to optimize the process. The developed DES reaction systems represent neat reactant mixtures enabling the lipase catalyzed esterification under solvent-free conditions.
Keywords
- (-)-Menthol, Biocatalysis, Deep eutectic solvents, Lipase, Solvent-free reaction conditions, Terpene esters
ASJC Scopus subject areas
- Chemical Engineering(all)
- Catalysis
- Chemical Engineering(all)
- Process Chemistry and Technology
- Chemistry(all)
- Physical and Theoretical Chemistry
Cite this
- Standard
- Harvard
- Apa
- Vancouver
- BibTeX
- RIS
In: Molecular Catalysis, Vol. 458, 10.2018, p. 67-72.
Research output: Contribution to journal › Article › Research › peer review
}
TY - JOUR
T1 - Synthesis of (-)-menthol fatty acid esters in and from (-)-menthol and fatty acids – novel concept for lipase catalyzed esterification based on eutectic solvents
AU - Hümmer, Magdalena
AU - Kara, Selin
AU - Liese, Andreas
AU - Huth, Ina
AU - Schrader, Jens
AU - Holtmann, Dirk
N1 - Funding Information: The financial support by the German Ministry of Education and Research (BMBF) for the project “NIESEL - Niedrig schmelzende eutektische Solventien als Lösungsmittel für die Biokatalyse” (Grant No. 031B0014C ) is gratefully acknowledged. The authors thank Florian Rudroff and Marko D. Mihovilovic (Institute of Applied Synthetic Chemistry, Vienna University of Technology) for the synthesis of the (-)-menthol dodecanoic acid ester. Furthermore, we would like to thank Dr. Jonathan Z. Bloh and Bastien Burek for the fruitful discussions.
PY - 2018/10
Y1 - 2018/10
N2 - Deep eutectic solvents (DESs) based on (-)-menthol and fatty acids (octanoic, decanoic and dodecanoic acid) were investigated as reaction media for the lipase catalyzed esterification of the DES compounds itself to synthesize (-)-menthol fatty acid esters. The DES acts as reaction medium and substrate pool simultaneously without the need of adding any solvent. Candida rugosa lipase was active in the neat (-)-menthol:fatty acid DESs to synthesize (-)-menthol fatty acid esters. This example shows for the first time that a valuable product can be enzymatically produced using both components of a DES without any co-solvent. The addition of water to the DESs enhanced the reaction outcome likely due to interfacial activation of the enzyme. In biphasic reaction systems with an addition of 10 wt% of water to the DES phase, the conversion (7 d) of octanoic, decanoic and dodecanoic acid reached 50%, 83% and 71%, respectively. This corresponds to a batch productivity of 133 g L−1 d−1 (24 h) and a final (-)-menthyl dodecanoate concentration of 957 mM (7 d) in the (-)-menthol:dodecanoic acid DES. Closer investigation of this DES reaction system revealed that water addition and stirring speed are interacting parameters to optimize the process. The developed DES reaction systems represent neat reactant mixtures enabling the lipase catalyzed esterification under solvent-free conditions.
AB - Deep eutectic solvents (DESs) based on (-)-menthol and fatty acids (octanoic, decanoic and dodecanoic acid) were investigated as reaction media for the lipase catalyzed esterification of the DES compounds itself to synthesize (-)-menthol fatty acid esters. The DES acts as reaction medium and substrate pool simultaneously without the need of adding any solvent. Candida rugosa lipase was active in the neat (-)-menthol:fatty acid DESs to synthesize (-)-menthol fatty acid esters. This example shows for the first time that a valuable product can be enzymatically produced using both components of a DES without any co-solvent. The addition of water to the DESs enhanced the reaction outcome likely due to interfacial activation of the enzyme. In biphasic reaction systems with an addition of 10 wt% of water to the DES phase, the conversion (7 d) of octanoic, decanoic and dodecanoic acid reached 50%, 83% and 71%, respectively. This corresponds to a batch productivity of 133 g L−1 d−1 (24 h) and a final (-)-menthyl dodecanoate concentration of 957 mM (7 d) in the (-)-menthol:dodecanoic acid DES. Closer investigation of this DES reaction system revealed that water addition and stirring speed are interacting parameters to optimize the process. The developed DES reaction systems represent neat reactant mixtures enabling the lipase catalyzed esterification under solvent-free conditions.
KW - (-)-Menthol
KW - Biocatalysis
KW - Deep eutectic solvents
KW - Lipase
KW - Solvent-free reaction conditions
KW - Terpene esters
UR - http://www.scopus.com/inward/record.url?scp=85052058003&partnerID=8YFLogxK
U2 - 10.1016/j.mcat.2018.08.003
DO - 10.1016/j.mcat.2018.08.003
M3 - Article
AN - SCOPUS:85052058003
VL - 458
SP - 67
EP - 72
JO - Molecular Catalysis
JF - Molecular Catalysis
SN - 2468-8231
ER -