Lipase‐catalyzed synthesis of glucose‐6‐O‐hexanoate in deep eutectic solvents

Abstract

Enzymatic synthesis of sugar fatty acid esters in organic solvents is a well-described procedure to synthesize glycolipids. This study aims at replacing these solvents with deep eutectic solvents (DES), a group of solvents that gained more and more interest during the last years, since they can be easily produced from non-toxic resources. Enzymatic glycolipid synthesis in deep eutectic solvents was investigated, employing Candida antarctica lipase B (Novozyme 435) in various deep eutectic solvents. A successful lipase-catalyzed synthesis of glucose fatty acid esters gave proof of this concept, while using the two deep eutectic solvents consisting of choline chloride and urea (CC : U) and choline chloride and glucose (CC : Glc). Additionally the DES consisting of choline chloride and glucose was observed to act as solvent and substrate for the synthesis at the same time.Practical application Glycolipids find applications in many everyday products like cosmetic and pharmaceutical formulations, food and classic cleaning products, utilizing their good detergent or emulsification properties. Glycolipids can, among other routes, be synthesized via lipase-catalyzed reactions, which are often carried out in organic solvents. By replacing these organic solvents with more ecologically friendly solvents like deep eutectic solvents, the reaction might be improved and the amount of waste produced could be reduced.

Deep Eutectic Solvents for Organocatalysis, Biotransformations, and Multistep Organocatalyst/Enzyme Combinations

“…In this latter case, apart from the classic ChCl/urea DES, another DES based on ChCl and glucose was used. Thus, the DES acted as the solvent and substrate for the reaction (Scheme ) …”

ChemInform Abstract: Deep Eutectic Solvents for Organocatalysis, Biotransformations, and Multistep Organocatalyst/Enzyme Combinations

“…[27] Likewise, important for DES is their ability to dissolve substrates of different polarities, thus they are highly useful in lipophilization reactions, [28] which typicallyc ombine two substrates with differentp olarities, and in the lipase-catalyzed esterification of sugarst oa fford, for example, glucose 6-hexanoates (Scheme 6). [29] In this latter case, apart from the classic ChCl/urea DES, another DES based on ChCl and glucose was used. Thus, the DES acted as the solventa nd substrate for the reaction(Scheme 6).…”

“…Thus, the DES acted as the solventa nd substrate for the reaction(Scheme 6). [29] The approach resembles the above-described HMF production process, in whichf ructose wasa ctually part of the DES and the substrate for the reaction. Following on this rationale, in which DES is used not only as an inert reaction mediab ut also as the substrate source, the potentiali nteraction of some DES components (e.g.,H BDs such as glycerol) have always been somewhat expected as as ider eaction.…”

“…[18b] Scheme6.Lipase-catalyzed transesterificationu sing vinyl esters and glucose in DES. [29] ChemCatChem 2016, 8,1020 -1027 www.chemcatchem.org may retain some clustered structures in such aqueous solutions, and thus their role as "solvents" would still remain for biocatalysis. [23,24] Epoxide hydrolases display an improved enantioselectivity if DES are used as cosolvents, [36] some lyases (namely,b enzaldehydel yase) have shown activitiesi nD ES solutions of up to 30-40 %v /v (using ChCl-basedD ES with glycerol, urea, xylitol, etc.…”

Influence of Hierarchical Interfacial Assembly on Lipase Stability and Performance in Deep Eutectic Solvent

“…33 There remains a need to demonstrate the performance of these hierarchical structures under commercially relevant conditions; specifically, limited 3 research exists on the use of deep eutectic solvents for the production of sugar esters. 15,37 Further, understanding how nanoparticles and core material influence enzyme stability can help develop industrially feasible immobilized enzyme systems. analyze kinetic parameters pH stability, and performance in ChCl:U.…”