54549-24-5Relevant articles and documents
Sweet surfactants: Packing parameter-invariant amphiphiles as emulsifiers and capping agents for morphology control of inorganic particles
Voggel, Michael,Meinusch, Rebecca M.,Siewert, Vanessa,Kunkel, Marius,Wittmann, Valentin,Polarz, Sebastian
, p. 7214 - 7227 (2018/09/26)
Surfactants are not only pivotal constituents in any biological organism in the form of phospholipids, they are also essential for numerous applications benefiting from a large, internal surface, such as in detergents, for emulsification purposes, phase transfer catalysis or even nanoparticle stabilization. A particularly interesting, green class of surfactants contains glycoside head groups. Considering the variability of glycosides, a large number of surfactant isomers become accessible. According to established models in surfactant science such as the packing parameter or the hydrophilic lipophilic balance (HLB), they do not differ from each other and should, thus, have similar properties. Here, we present the preparation of a systematic set of glycoside surfactants and in particular isomers. We investigate to which extent they differ in several key features such as critical aggregation concentration, thermodynamic parameters, etc. Analytical methods like isothermal titration calorimetry (ITC), tensiometry, dynamic light scattering (DLS), small angle-X-ray scattering (SAXS), transmission electron microscopy (TEM) and others were applied. It was found that glycosurfactant isomers vary in their emulsification properties by up to two orders of magnitude. Finally, we have investigated the role of the surfactants in a microemulsion-based technique for the generation of zinc oxide (ZnO) nanoparticles. We found that the choice of the carbohydrate head has a marked effect on the shape of the formed inorganic nanocrystals.
Chemoenzymatic synthesis of β-D-glucosides using cellobiose phosphorylase from Clostridium thermocellum
De Winter, Karel,Van Renterghem, Lisa,Wuyts, Kathleen,Pelantová, Helena,K?en, Vladimír,Soetaert, Wim,Desmet, Tom
, p. 1961 - 1969 (2015/06/02)
Abstract Over the past decade, disaccharide phosphorylases have been successfully applied for the synthesis of numerous α-glucosides. In contrast, much less research has been done with respect to the production of β-glucosides. Although cellobiose phosphorylase was already successfully used for the synthesis of various disaccharides and branched trisaccharides, its glycosylation potential towards small organic compounds has not been explored to date. Unfortunately, disaccharide phosphorylases typically have a very low affinity for non-carbohydrate acceptors, which urges the addition of solvents. The ionic liquid AMMOENGTM 101 and ethyl acetate were identified as the most promising solvents, allowing the synthesis of various β-glucosides. Next to hexyl, heptyl, octyl, nonyl, decyl and undecyl β-D-glucopyranosides, also the formation of vanillyl 4-O-β-D-glucopyranoside, 2-phenylethyl β-D-glucopyranoside, β-citronellyl β-D-glucopyranoside and 1-O-β-D-glucopyranosyl hydroquinone was confirmed by nuclear magnetic resonance spectroscopy and mass spectrometry. Moreover, the stability of cellobiose phosphorylase could be drastically improved by creating cross-linked enzyme aggregates, while the efficiency of the biocatalyst for the synthesis of octyl β-D-glucopyranoside was doubled by imprinting with octanol. The usefulness of the latter system was illustrated by performing three consecutive batch conversions with octanol imprinted cross-linked enzyme aggregates, yielding roughly 2 g of octyl β-D-glucopyranoside.
Biphasic catalysis with disaccharide phosphorylases: Chemoenzymatic synthesis of α- D -glucosides using sucrose phosphorylase
De Winter, Karel,Desmet, Tom,Devlamynck, Tim,Van Renterghem, Lisa,Verhaeghe, Tom,Pelantova, Helena,Kren, Vladimir,Soetaert, Wim
, p. 781 - 787 (2014/07/08)
Thanks to its broad acceptor specificity, sucrose phosphorylase (SP) has been exploited for the transfer of glucose to a wide variety of acceptor molecules. Unfortunately, the low affinity (Km > 1 M) of SP towards these acceptors typically urges the addition of cosolvents, which often either fail to dissolve sufficient substrate or progressively give rise to enzyme inhibition and denaturation. In this work, a buffer/ethyl acetate ratio of 5:3 was identified to be the optimal solvent system, allowing the use of SP in biphasic systems. Careful optimization of the reaction conditions enabled the synthesis of a range of α-d-glucosides, such as cinnamyl α-d-glucopyranoside, geranyl α-d-glucopyranoside, 2-O-α-d-glucopyranosyl pyrogallol, and series of alkyl gallyl 4-O-α-d-glucopyranosides. The usefulness of biphasic catalysis was further illustrated by comparing the glucosylation of pyrogallol in a cosolvent and biphasic reaction system. The acceptor yield for the former reached only 17.4%, whereas roughly 60% of the initial pyrogallol was converted when using biphasic catalysis.
