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Microwave Assisted Enzymatic Synthesis of Fatty Acid Sugar Ester in Ionic Liquid-tert-Butanol Biphasic Solvent System

Authors:
Mohd Basyaruddin Abdul Rahman at Universiti Putra Malaysia
Mohd Basyaruddin Abdul Rahman
Mahashanon Arumugam at University of Chemistry and Technology, Prague
Mahashanon Arumugam
Nik Sasha Khatrina Khairuddin at Malaysian Palm Oil Board
Nik Sasha Khatrina Khairuddin
Emilia Abdulmalek at Universiti Putra Malaysia
Emilia Abdulmalek
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Abstract

Microwave enhanced enzymatic synthesis of fatty acid sugar ester (FASE), glucose oleate in biphasic solvent system comprising of an ionic liquid, 1-butyl-3-methylimidazolium tetrafluoroborate, [BMIM][BF4] and tert-butanol were studied comparative to other conventional heating's. The effect of biphasic solvents in synthesizing glucose oleate and optimization of reaction parameters, in terms of temperature, time and lipase were screened in microwave reactor relative to water bath shaker and hot plate stirrer. In microwave, the enzyme screening showed Novozym 435 had the optimal activity at 60 °C and time 0.5 h and maximum conversion of oleic acid to glucose oleate was 90 %. Microwave proved to be an efficient heating system for glucose oleate synthesis at much reduced time than conventional heatings.
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... In fact, lipases from different sources have already showed interesting catalytic activities in ILs (Hernández-Fernández et al. 2010). For example, the esterification or transesterification activities, necessary to produce the sugar fatty acid esters (SFAEs), have been reported for lipases from Candida antarctica, Candida rugosa, Pseudomonas cepacia, Thermomyces lanuginosus, Rhizomucor miehei, Bacillus subtilis, or porcine pancreas (Nara et al. 2002;Gubicza et al. 2003;Byun et al. 2007;de los Ríos et al. 2007;Abdulmalek et al. 2012;Gumel and Annuar 2016;Chado et al. 2018). Nevertheless, lipase from C. antarctica is the most widely studied among all the available sources. ...
... The application of microwave irradiation in the synthesis of glucose oleate performed in a biphasic mixture of [BMIM][BF 4 ]:t-butanol (1.5:1, v/v) allowed to increase lipase activity and remarkably reduce the reaction time to 30 min (Rahman et al. 2012 [BF 4 ]/2M2B (20/80% v/v) were used in the synthesis of fructose laurate (mono-and diesters) through lipase-catalyzed esterification . The substrate solubility, limitations of mass transfer, and interactions of lipase-IL were pointed out as the most relevant factors in the formation of fructose esters. ...
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  • Sep 2020
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... Diverse immobilization techniques were reported in our dataset, which includes immobilization by interfacial adsorption on hydrophobic supports, covalent bonding, and ionic interactions. The methods listed included CALB immobilization on different pretreated supports, such as: chitosan, celite, silica magnetic microparticles, octyl-silica [41,74,95,96], and microemulsion based organogels (MBGs) [97,98]. We also verified that the use of commercial pre-immobilized CALB (Novozym 435, N435) that occurred in about 82% of the publications, and acheived the highest sugar ester yields [39,60,95,[99][100][101][102]. ...
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Article
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Article
Full-text available
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Effects of Particle Size of Sucrose Suspensions and Pre-incubation of Enzymes on Lipase-Catalyzed Synthesis of Sucrose Oleic Acid Esters
Article
  • Nov 2014
The effects of high-speed homogenization, high-intensity ultrasound, and their combination were evaluated for the reduction of the particle size of sucrose crystals to enhance solvent-free lipase-catalyzed synthesis of sucrose oleate at 65 degrees C. The combination of homogenization and ultrasound greatly decreased the particle size of suspended sucrose crystals in mixtures of oleic acid/sucrose oleate (86 wt% monoester and 14 wt% diester at a ratio of 90/10 w/w) from 88 to 18 mu m. The suspension-based medium was charged to a stirred tank bioreactor that also contained immobilized lipase from Rhizomucor miehei or Candida antarctica (Lipozyme (R) IM and Novozym (R) 435, respectively; Novozymes, Franklinton, NC, USA), that was pre-incubated in oleic acid for several different temperatures (23-60 degrees C), durations (4-24 h), and stir rates (50-400 rpm, radius of 3 cm), prior to use. The optimal performance was achieved using C. antarctica lipase (83.3 wt% ester, consisting of 46 wt% monoester) in the presence of molecular sieves (18 wt%). The low water concentration (similar to 0.12 wt%) did not affect the activity of C. antarctica lipase.
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Microwave-Assisted Chemistry of Carbohydrates
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Microwave irradiation is becoming an increasingly popular method of heating which replaces the classical one because it proves to be a clean, cheap, and convenient method. Often, it affords higher yields and results in shorter reaction times. This method of heating has been extended to almost all areas of chemistry with the exception of the carbohydrate chemistry which has suffered a certain delay, as it is testified by the limited number of applications. The aim of this review is to explore the variety of these applications in carbohydrate chemistry, even if in a limited number, which have been carried out with microwave irradiation as activating agent. Mainly, these concern the selective or unselective protection and deprotection of hydroxyl functionalities, and triglyceride alcoholysis and glycerolysis reactions of industrial interest since these lead to materials for the production of straining, emulsifying and softening agents and moreover for the production of an ecologic fuel (biodiesel). Other aspects of the carbohydrate chemistry such as the syntheses of monosaccharides containing heterocyclic nuclei, or unsaturations, or halogens are also included. Synthetically, the effect on the mutarotation phenomenon, polysaccharides, methanolysis and hydrolysis of saccharides, flavour formation deriving from the interactions of sugars with amino acids, and sterospecific activation of the C-H bond for the deuterium and tritium labelling are reported. In several cases, a comparison is made between results obtained with conventional and microwave-assisted methods.
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Microwave irradiations are known to alter the rate of chemical reactions. Often this results in enhanced reaction rates; higher yields, purity of products; more efficient and homogeneous distribution of energy and heating effects, and easier water elimination. The enzyme lipase (triacylglycerol ester hydrolase, EC 3.1.1.3) is a special class of esterase enzyme that acts on fats and oils and hydrolyses them in steps into the substituted glycerides and fatty acids, and finally on complete hydrolysis into glycerol and fatty acid. Hydrolysis of triolein using a fungus, Aspergillus carneus lipase has been carried out both under normal conditions and microwave irradiations of LOW 10 (175 W, 38-40°C) and HIGH 100 (800 W, 90°C). Analysis of the hydrolytic products on TLC plates showed the presence of triolein, diolein, monolein and oleic acid in 24 h under normal conditions, compared to microwave irradiations where it took 45-90 s under LOW power level and 15-30 s under HIGH power level for the production of monolein and oleic acid. However, complete hydrolysis of triolein took place in 160 s at LOW power and 75 s at HIGH power level. The synthesis of bioester, biosurfactant and glycerides could successfully be carried out rapidly within 30 s under both solvent-containing and solvent-free condition under HIGH power microwave irradiation.
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Optimization of lipase-catalyzed synthesis of xylitol ester by Taguchi robust design method
Article
  • Mar 2010
  • IND CROP PROD
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Article
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Optimization of lipase-catalyzed glucose fatty acid ester synthesis in a two-phase system containing ionic liquids and t-BuOH
Article
  • Nov 2005
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Selective lipase-catalyzed synthesis of glucose fatty acid esters in two-phase systems consisting of an ionic liq. (1-butyl-3-Me imidazolium tetrafluoroborate [BMIM][BF4] or 1-butyl-3-Me imidazolium hexafluorophosphate [BMIM][PF6]) and tert-butanol as org. solvent was investigated. The best enzyme was com. available lipase B from Candida antarctica (CAL-B), but also lipase from Thermomyces lanuginosa (TLL) gave good conversion. After thorough optimization of several reaction conditions (chain-length and type of acyl donor, temp., reaction time, percentage of co-solvent) conversions up to 60% could be achieved using fatty acid vinyl ester as acyl donors in [BMIM][PF6] in the presence of 40% t-BuOH with CAL-B at 60°C. [on SciFinder(R)]
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Lipase-catalyzed synthesis of fatty acid fructose esters
Article
  • Dec 2006
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Ionic Liquids: Green Solvents for Nonaqueous Biocatalysis
Article
  • Jun 2005
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Ionic liquids hold potential as green solvents because of their lack of vapour pressure, and are opening up a burgeoningly new field of nonaqueous enzymology. As compared to those observed in conventional organic solvents, enzymes in ionic liquids have presented enhanced activity, stability, and selectivity. Advantages of using ionic liquids over the use of normal organic solvents as reaction medium for biocatalysis also include their high ability of dissolving a wide variety of substrates, especially those highly polar ones, and their widely tunable solvent properties through appropriate modification of the cations and anions. In this review, we discuss the solvent properties of ionic liquids, their effects on enzyme performance such as activity, stability and selectivity, and their applications in biocatalysis.
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Microwave Super-Heated Boiling of Organic Liquids: Origin, Effect and Application
Article
This paper reports the state of the art of the microwave super-heated boiling phenomenon. When a liquid is heated by microwaves, the temperature increases rapidly to reach a steady temperature while refluxing. It happens that this steady state temperature can be up to 40 K higher than the boiling point of the liquid. With the same reactor, overheating is not observed under conventional heating. The bulk temperature of a microwaved solvent under boiling depends on many factors: physical properties of the solvent, reactor geometry, mass flow, heat flow, and electric field distribution. The influence of these factors is studied and discussed. The kinetics of homogeneous organic reactions shows an extension of Arrhenius behaviour into the superheated temperature region. Reaction rate enhancement of order 10-100 can thus be achieved, which is normally only possible under pressure. Finally, we present a model predicting reaction kinetics and yields under classical and microwave heating, based on predicted temperature profiles in agreement with experimental data.
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Improved Preparation and Use of Room-Temperature Ionic Liquids in Lipase-Catalyzed Enantio- and Regioselective Acylations
Article
  • Dec 2001
Polar organic solvents such as methanol or N-methylformamide inactivate lipases. Although ionic liquids such as 3-alkyl-1-methylimidazolium tetrafluoroborates have polarities similar to these polar organic solvents, they do not inactivate lipases. To get reliable lipase-catalyzed reactions in ionic liquids, we modified their preparation by adding a wash with aqueous sodium carbonate. Lipase-catalyzed reactions that previously did not occur in untreated ionic liquids now occur at rates comparable to those in nonpolar organic solvents such as toluene. Acetylation of 1-phenylethanol catalyzed by lipase from Pseudomonas cepacia (PCL) was as fast and as enantioselective in ionic liquids as in toluene. Ionic liquids permit reactions in a more polar solvent than previously possible. Acetylation of glucose catalyzed by lipase B from Candida antarctica (CAL-B) was more regioselective in ionic liquids because glucose is up to one hundred times more soluble in ionic liquids. Acetylation of insoluble glucose in organic solvents yielded the more soluble 6-O-acetyl glucose, which underwent further acetylation to give 3,6-O-diacetyl glucose (2-3:1 mixture). However, acetylation of glucose in ionic liquids yielded only 6-O-acetyl glucose (>13:1 and up to >50:1).
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