scholarly journals Simplified Method to Optimize Enzymatic Esters Syntheses in Solvent-Free Systems: Validation Using Literature and Experimental Data

Catalysts ◽  
2021 ◽  
Vol 11 (11) ◽  
pp. 1357
Author(s):  
Ronaldo Rodrigues de Sousa ◽  
Ayla Sant’Ana da Silva ◽  
Roberto Fernandez-Lafuente ◽  
Viridiana Santana Ferreira-Leitão
Keyword(s):  
Immobilized Lipase ◽  
Solvent Free ◽  
Molar Ratio ◽  
Mathematical Tool ◽  
Enzymatic Esterification ◽  
Reaction Conditions ◽  
Reaction Behavior ◽  
Optimum Reaction ◽  
Interesting Correlation ◽  
Using Data

The adoption of biocatalysis in solvent-free systems is an alternative to establish a greener esters production. An interesting correlation between the acid:alcohol molar ratio and biocatalyst (immobilized lipase) loading in the optimization of ester syntheses in solvent-free systems had been observed and explored. A simple mathematical tool named Substrate-Enzyme Relation (SER) has been developed, indicating a range of reaction conditions that resulted in high conversions. Here, SER utility has been validated using data from the literature and experimental assays, totalizing 39 different examples of solvent-free enzymatic esterifications. We found a good correlation between the SER trends and reaction conditions that promoted high conversions on the syntheses of short, mid, or long-chain esters. Moreover, the predictions obtained with SER are coherent with thermodynamic and kinetics aspects of enzymatic esterification in solvent-free systems. SER is an easy-to-handle tool to predict the reaction behavior, allowing obtaining optimum reaction conditions with a reduced number of experiments, including the adoption of reduced biocatalysts loadings.

Optimization of Chiral Resolution of (+/-)-1-Phenylethanol by Statistical Methods

2011 ◽  
Vol 9 (1) ◽  
Author(s):  
Ganapati D. Yadav ◽  
Jyoti B. Sontakke
Keyword(s):  
Kinetic Resolution ◽  
Batch Reactor ◽  
Immobilized Lipase ◽  
Enantiomeric Excess ◽  
Molar Ratio ◽  
Catalyst Loading ◽  
Acyl Donor ◽  
Reaction Conditions ◽  
Optimum Reaction ◽  
Synthetic Intermediate

Optically active 1-phenylethanol is used as a chiral building block and synthetic intermediate in pharmaceutical and fine-chemical industries. Lipase - catalyzed kinetic resolution of (R,S)-1-phenylethanol with vinyl acetate as an acyl donor and Candida antarctica immobilized lipase as a biocatalyst in a batch reactor was optimized using Response Surface Methodology (RSM). Four-factor-five-level central composite rotatable design (CCRD) was employed to evaluate the effect of synthesis parameters such as speed of agitation, enzyme loading, temperature and acyl donor/alcohol molar ratio, on conversion, enantiomeric excess (ee), enantioselectivity and initial rate. Optimum reaction conditions obtained were; mole ratio of acyl donor: ester of 2:1, temperature of 42.5 °C, catalyst loading of 1.6x10-3 g.cm-3 and speed of agitation of 336 rpm. Analysis of variance was performed to determine significantly affecting variables and interactions between the process parameters.

Study on the Synthesis of Isoamyl Acetate Catalyzed by Strong Acidic Cation Exchange Resin

2011 ◽  
Vol 396-398 ◽  
pp. 2411-2415 ◽  
Author(s):  
Ping Lan ◽  
Li Hong Lan ◽  
Tao Xie ◽  
An Ping Liao
Keyword(s):  
Acetic Acid ◽  
Reaction Time ◽  
Cation Exchanger ◽  
Cation Exchange Resin ◽  
Isoamyl Acetate ◽  
Molar Ratio ◽  
Esterification Reaction ◽  
Reaction Conditions ◽  
Optimum Reaction

Isoamyl acetate was synthesized from isoamylol and glacial acetic acid with strong acidic cation exchanger as catalyst. The effects of reaction conditions such as acid-alcohol ratio, reaction time, catalyst dosage to esterification reaction have been investigated and the optimum reaction conditions can be concluded as: the molar ratio of acetic acid to isoamylol 0.8:1, reaction time 2h, 25 % of catalyst (quality of acetic acid as benchmark). The conversion rate can reach up to 75.46%. The catalytic ability didn’t reduce significantly after reusing 10 times and the results showed that the catalyst exhibited preferably catalytic activity and reusability.

Study on Synthesis of Cyclotriphosphazene Containing Aminopropylsilicone Functional Group as Flame Retardant

2013 ◽  
Vol 683 ◽  
pp. 25-29 ◽  
Author(s):  
Lan Lan He ◽  
Yi Zhang ◽  
Zhao Lu Qin ◽  
Yan Hua Lan ◽  
Ding Hua Li ◽  
...  
Keyword(s):  
Flame Retardant ◽  
Chemical Structure ◽  
Gel Permeation Chromatography ◽  
Molar Ratio ◽  
Reaction Conditions ◽  
Element Analysis ◽  
Fourier Transformed Infrared Spectroscopy ◽  
Industrial Grade ◽  
Distribution Calculation ◽  
Optimum Reaction

A novel non-halogen flame retardant APESP, cyclotriphosphazene containing six aminopropyltriethoxysilicone functional groups N3P3[NH(CH2)3Si(OCH2CH3)3]6, was synthesized by menas of SN2 nucleophilic substitution reaction, using hexachlorocyclotriphosphazene(HCCP) and 3-aminopropyltriethoxy-silane (KH550) as material. Firstly the industrial grade HCCP was purified through recrystallization and sublimation. Then the reaction process was investigated to prompt the yield, and the optimum reaction conditions were as follows: triethylamine as acid-binding agent, tetrahydrofuran as solvent, HCCP/KH550/triethylamine molar ratio 1:7.2:7.2, dripping time: 1 hour, temperature: 67°C and reaction time: 20h. Maximum APESP yield reached 94.3%. The chemical structure and purity was characterized by element analysis, Fourier-transformed infrared spectroscopy (FTIR), mass spectrum, gel permeation chromatography (GPC) and nuclear magnetic resonance (NMR) analysis. The results showed that the structure of synthesized product is consistent with the theoretical structure, in which the chlorine atoms were completely substituted. The charge distribution calculation of HCCP and KH550 confirmed the reaction mechanism.

scholarly journals Incorporation of capric acid in pumpkin seed oil by sn-1,3 regioselective lipase-catalyzed acidolysis

OCL ◽  
2018 ◽  
Vol 25 (3) ◽  
pp. A302 ◽  
Author(s):  
Vanessa Sousa ◽  
Vitor Campos ◽  
Patrícia Nunes ◽  
Paula Pires-Cabral
Keyword(s):  
Seed Oil ◽  
Immobilized Lipase ◽  
Structured Lipids ◽  
Capric Acid ◽  
Solvent Free ◽  
Molar Ratio ◽  
Lipozyme Tl Im ◽  
Fixed Amount ◽  
Pumpkin Seed ◽  
Pumpkin Seed Oil

Structured lipids (SLs) are novel triacylglycerols obtained by changing the native fatty acid (FA) profiles or by the incorporation of a new desired FA in the acylglycerol backbone. These modified fats present important medical and functional properties for food applications. This work aimed to synthetize a MLM-type SL, which consists of triacylglycerols containing a medium-chain FA (M) at sn-1,3 positions and a long-chain FA (L) at sn-2 position, by acidolysis of pumpkin seed oil with capric acid, catalyzed by a commercial lipase preparation from Thermomyces lanuginosa (Lipozyme TL IM). Reactions were performed at 45 °C, in solvent-free media, at 1:2 molar ratio (pumpkin seed oil:capric acid) and a fixed amount of immobilized lipase of 5%, 10%, 15% or 20%. Incorporations of C10:0 increased with time up to 31 h (29.9 ± 0.7 mol-%) when 5% lipase load was used. Significant differences were only observed between the results obtained with 5 and 20% of biocatalyst load. The subsequent experiment was carried out with 5% lipase load, at 45 °C, 1:2 molar ratio and in the presence of n-hexane. The results showed slightly higher incorporation yields in the presence of solvent, namely at 48 h-reaction (34.7 ± 1.0 mol-%). However, since the structured lipids are to be used in food products, together with environmental and economic concerns, solvent-free systems are preferred. In this study, the synthesis of a MLM-type SL from pumpkin seed oil for food uses was well succeeded.

A New Technological Study on Synthesis of Bis(2-chloroethoxy)Methane

2014 ◽  
Vol 1033-1034 ◽  
pp. 7-11
Author(s):  
Yan Bai ◽  
Xuan Tang ◽  
Kui Zhou ◽  
Cun She Zhang
Keyword(s):  
Mass Fraction ◽  
Acid Catalysis ◽  
Molar Ratio ◽  
Optimum Conditions ◽  
Reaction Conditions ◽  
Ethylene Chlorohydrin ◽  
Optimum Reaction ◽  
Chromatographic Detection ◽  
Catalyst Dosage ◽  
Technological Study

bis(2-chloroethoxy)methane was synthesized by the reaction of ethylene chlorohydrin and Oligopolyformaldehyde under sulfuric acid catalysis. optimum reaction conditions obtained were as follows: the molar ratio of Oligopolyformaldehyde and ethylene chlorohydrin of 1.2:2, catalyst dosage was 5‰mass fraction of ethylene chlorohydrin, toluene were chose as water-carrying agent, All reactant were refluxed on temperature of 110°C until no water generated. Under the optimum conditions the yield of bis(2-chloroethoxy)methane was 97.7%. The structure of bis(2-chloroethoxy)methane were conformed by ATR IR. The purity of bis(2-chloroethoxy)methane were 99% by gas chromatographic detection.

Catalytic Synthesis of Isoamyl Acetate Catalyzed by (NH4)6[MnMo9O32]•8H2O Supported Activated Carbon with Waugh Structure

2013 ◽  
Vol 781-784 ◽  
pp. 190-193
Author(s):  
Mei Xu ◽  
Hua Yuan ◽  
Wei Liu ◽  
Jian Wang ◽  
Feng Zhen Yang
Keyword(s):  
Acetic Acid ◽  
Activated Carbon ◽  
Reaction Time ◽  
Conversion Rate ◽  
Isoamyl Alcohol ◽  
Isoamyl Acetate ◽  
Catalytic Synthesis ◽  
Molar Ratio ◽  
Reaction Conditions ◽  
Optimum Reaction

The synthesis of isoamyl acetate with ammonium 9-molybdate manganese heteropolyacid salt supported activated carbon as catalyst was studied. The optimum reaction conditions are obtained as follows: isoamyl alcohol to acetic acid molar ratio = 1.646, the weight of catalyst is 40% of total weigh, m (acidulate catalyst)=0.2g, m (water carrying reagent toluene) = 3ml, reaction time is about 63 minutes. Selectivity is 100% and conversion rate is 89.48%.

scholarly journals Two-Stage Conversion of High Free Fatty AcidJatropha curcasOil to Biodiesel Using Brønsted Acidic Ionic Liquid and KOH as Catalysts

2014 ◽  
Vol 2014 ◽  
pp. 1-9 ◽  
Author(s):  
Subrata Das ◽  
Ashim Jyoti Thakur ◽  
Dhanapati Deka
Keyword(s):  
Ionic Liquid ◽  
Molar Ratio ◽  
Reaction Conditions ◽  
Two Stage ◽  
Second Stage ◽  
Stage Conversion ◽  
Acidic Ionic Liquid ◽  
Brønsted Acidic Ionic Liquid ◽  
Optimum Reaction ◽  
Stage Process

Biodiesel was produced from high free fatty acid (FFA)Jatropha curcasoil (JCO) by two-stage process in which esterification was performed by Brønsted acidic ionic liquid 1-(1-butylsulfonic)-3-methylimidazolium chloride ([BSMIM]Cl) followed by KOH catalyzed transesterification. Maximum FFA conversion of 93.9% was achieved and it reduced from 8.15 wt% to 0.49 wt% under the optimum reaction conditions of methanol oil molar ratio 12 : 1 and 10 wt% of ionic liquid catalyst at 70°C in 6 h. The ionic liquid catalyst was reusable up to four times of consecutive runs under the optimum reaction conditions. At the second stage, the esterified JCO was transesterified by using 1.3 wt% KOH and methanol oil molar ratio of 6 : 1 in 20 min at 64°C. The yield of the final biodiesel was found to be 98.6% as analyzed by NMR spectroscopy. Chemical composition of the final biodiesel was also determined by GC-MS analysis.

scholarly journals Optimization of the Lipase Catalyzed Production of Structured Acylglycerols With Polyunsaturated Fatty Acids Isolated From Sardine Oil

2013 ◽  
Vol 2 (6) ◽  
pp. 97 ◽  
Author(s):  
Juan Antonio Noriega-Rodriguez ◽  
Esther Carrillo-Perez ◽  
Nohemi Gamez-Meza ◽  
Luis A. Medina-Juarez ◽  
Ramiro Baeza-Jimenez ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Polyunsaturated Fatty Acids ◽  
Immobilized Lipase ◽  
Reaction Times ◽  
Molar Ratio ◽  
Reaction Conditions ◽  
Molar Ratios ◽  
Sardine Oil ◽  
Different Temperatures ◽  
Urea Crystallization

<p>In the present work, direct enzyme-catalyzed esterification of n-3 polyunsaturated fatty acids (n-3 PUFA) isolated from sardine oil was optimized to obtain structured acyglycerols. A n-3 PUFA concentrate was prepared by urea crystallization of refined sardine oil and esterification was carried out mixing free fatty acids and glycerol at different molar ratios (<em>M</em> = 0.48, 1.5, 3.0, 4.5 and 5.52 mol/mol), using an immobilized lipase preparation from <em>Candida antarctica</em> (NV-435) at different temperatures (<em>T</em> = 38, 45, 55, 65 and 72 °C) and reaction times (<em>t</em> = 0.7, 2.75, 5.75, 8.75 and 10.8 h) in a rotatable central composition design. The degree of esterification was determined by analysis of the acylglycerides produced, using liquid chromatography (HPLC-ELSD). Optimization by response surface methodology (RSM) showed that in order to obtain higher esterification levels of n-3 PUFA to glycerol (99.5%), a molar ratio of 1.3 mol n-3 PUFA/mol glycerol, time 8.3 h and temperature 38 °C, are required. However, results of this work show that it is possible to drive the reaction to any determined product (MAG, DAG or TAG) by modifying the reaction conditions.</p>

scholarly journals OPTIMASI PROSES PEMBUATAN BIODIESEL DARI ASAM LEMAK SAWIT DISTILAT (ALSD) DAN DIMETHYL CARBONATE (DMC) MENGGUNAKAN KATALIS NOVOZYM®435

2016 ◽  
Vol 5 (1) ◽  
pp. 13-19
Author(s):  
William ◽  
Johan Senjaya ◽  
Taslim ◽  
Tjahjono Herawan ◽  
Meta Rivani
Keyword(s):  
Fatty Acid ◽  
Reaction Time ◽  
Energy Content ◽  
Immobilized Lipase ◽  
Chemical Properties ◽  
Intermediate Compound ◽  
Biodiesel Production ◽  
Molar Ratio ◽  
Enzymatic Esterification ◽  
Dialkyl Carbonate

Biodiesel production has rapidly grown over the last decades, and it has attracted much attention in the market as fuel that promising substitute for petroleum diesel, because its physical and chemical properties and energy content are similar to those of petroleum diesel. The main problem in producing biodiesel is its high cost which could be reduced by use of less expensive feedstock. Therefore, in this work biodiesel is synthesized by enzymatic esterification from low quality feedstock which is unrefined and much cheaper than the refined oil, such as palm fatty acid distillate (PFAD) with dialkyl carbonate using immobilized lipase (Novozym®435). Enzymatic process has certain advantages over the chemical process, as it is less energy intensive, allowing the esterification of glycerides with high free fatty acid contents (PFAD, 85-95% FFA) and no enzymatic activity loss. Methanol replaced by dialkyl carbonate, especially DMC due to esterification (methanolysis) is close to equilibrium reaction whereas using DMC the intermediate compound immediately decomposes to carbon dioxide and an alcohol, which have been investigated. Moreover, DMC are cheap, eco-friendly chemical, non-toxic properties and widely available. Factors affecting the reaction such as DMC to PFAD molar ratio, reaction temperature, reaction time and catalyst concentration were systematically analyzed by response surface methodology (RSM) with central composite design (CCD). The optimal condition is using 6:1 molar ratio of DMC to PFAD at 60 oC, for a reaction time 3h in the presence 10wt% of catalyst (based on oil weight). The results showed that synthesis of biodiesel through enzymatic esterification using PFAD suitable for biodiesel production.

scholarly journals Valorization of Glycerol through the Enzymatic Synthesis of Acylglycerides with High Nutritional Value

Catalysts ◽  
2020 ◽  
Vol 10 (1) ◽  
pp. 116
Author(s):  
Daniel Alberto Sánchez ◽  
Gabriela Marta Tonetto ◽  
María Luján Ferreira
Keyword(s):  
Palmitic Acid ◽  
Burkholderia Cepacia ◽  
Nutritional Value ◽  
Acyl Migration ◽  
Capric Acid ◽  
Added Value ◽  
Molar Ratio ◽  
Attractive Alternative ◽  
Enzymatic Esterification ◽  
Reaction Conditions

The production of specific acylglycerides from the selective esterification of glycerol is an attractive alternative for the valorization of this by-product of the biodiesel industry. In this way, products with high added value are generated, increasing the profitability of the overall process and reducing an associated environmental threat. In this work, nutritional and medically interesting glycerides were obtained by enzymatic esterification through a two-stage process. In the first stage, 1,3-dicaprin was obtained by the regioselective esterification of glycerol and capric acid mediated by the commercial biocatalyst Lipozyme RM IM. Under optimal reaction conditions, 73% conversion of fatty acids and 76% selectivity to 1,3-dicaprin was achieved. A new model to explain the participation of lipase in the acyl migration reaction is presented. It evaluates the conditions in the microenvironment of the active site of the enzyme during the formation of the tetrahedral intermediate. In the second stage, the esterification of the sn-2 position of 1,3-dicaprin with palmitic acid was performed using the lipase from Burkholderia cepacia immobilized on chitosan as the biocatalyst. A biocatalyst containing 3 wt % of lipase showed good activity to esterify the sn-2 position of 1,3-dicaprin. A mixture of acylglycerides consisting mainly of capric acid esterified at sn-1 and sn-3, and of palmitic acid at the sn-2 position was obtained as the reaction product. The influence of the biocatalyst mass, the reaction temperature, and the molar ratio of substrates were evaluated for this reaction using a factorial design. Simple models were used to adjust the consumption of reagents and the generation of different products. The reaction product contained between 76% and 90% of acylglycerides with high nutritional value, depending on the reaction conditions.

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