Diisopropyl Ether Research Articles

Sustainable recovery of phenolic antioxidants from real olive vegetation water with natural hydrophobic eutectic solvents and terpenoids

Olive oil production leads to the generation of olive mill wastewater (OMWW). Due to the presence of phenolic compounds, they are difficult to process, but they represent a source of high-added value chemicals since they have antioxidant and therapeutic properties. This work has studied the extraction of phenolic compounds from a type of OMWW, olive vegetation water, which presents these compounds in a more diluted dosage than in other studied to date, to revalue this waste stream. A real olive vegetation water from a Spanish olive oil producer was used, and liquid-liquid extraction was applied. Terpenoids and terpene-based hydrophobic eutectic solvents were systematically used to extract phenolic compounds following the concentrations of tyrosol, catechol, caffeic acid, and total phenolic content. By molecular simulation with the COSMO-RS method, 4 terpenoids, and 2 eutectic solvents were selected and compared with 2 conventional solvents. The Solvent/Feed ratio in the extraction of phenolic compounds was studied, showing that the solvents with the highest extraction results were geraniol, eucalyptol, and eutectic solvent menthol + camphor, which outperformed conventional solvents methyl isobutyl ketone and diisopropyl ether. Menthol + camphor gave total phenol extraction yields of 88.73% at a Solvent/Feed ratio in volume of 0.50, surpassing all solvents tested. A solvent reuse and regeneration process was applied by back-extraction of the 4 solvents: FTIR results showed the stability of the solvents while maintaining yields in the solvent reuse process. The phenolic compounds could be concentrated in the alkaline phase to factors up to 49.3 to the initial concentration in olive vegetation water. The alkaline phases were neutralized to obtain a precipitate with a caffeic acid content of up to 26 % wt%, and a tyrosol-rich supernatant with a concentration of up to 6.54 g/L. This work proposes a process using natural solvents to extract phenolic compounds from olive vegetation water.

Development of rapid analysis of eye drops for monitoring during various technological operations

In this article, the composition and technology of combined eye drops were developed, including taurine as an anti-cataract agent and betaxolol hydrochloride as an anti-glaucoma agent. Butanol, toluene, isopropyl ether, chloroform, ammonia 25%, ethyl alcohol in various ratios were used as the mobile phase. However, these solutions and their combinations did not allow us to determine a system that makes it possible to register both active components simultaneously. Therefore, it was decided to select two thin layer chromatography systems, one of which made it possible to determine taurine, and the other betaxolol hydrochloride

Extraction of H3PO4 from low-grade phosphate rocks leachate of HCl-route by the mixture of TBP and IPE: Optimization, mass transfer and mechanism

The mixed solvent of tributylphosphate and isopropyl ether was used to extract H3PO4 and separate Ca2+ and Cl− from low concentration wet process phosphoric acid prepared by low-grade collophane and 30 wt% hydrochloric acid solution. Then, the effects of extraction temperature, composition of solvent mixture, aqueous/organic phase ratio, extraction time and extraction stage were investigated, respectively. The result shows that the extraction process of H3PO4 is an exothermic process and the enthalpy changes (ΔH) is −12.50 kJ mol−1. The McCabe–Thiele diagram shows two counter-current stages achieves about 76.9 wt% H3PO4 extraction at 293 K. Based on the mass transfer theory of liquid–liquid extraction, extraction yields for all tested component were summarized as an exponential function of cross-flow extraction stages. Meanwhie, extraction mechanism studies show that the comlex of αH3PO4 βTBP was formed in extraction process and higher Ca2+ concentration was beneficial for H3PO4 extraction. Meanwhile, the effects of stripping temperature, aqueous/organic phase ratio and stripping time on the re-extraction performance of H3PO4, Ca2+ and Cl− were studied, respectively. The result of experiment will provide some theoretical support for the industrial application of HCl-route wet process phosphoric acid on low-grade phosphate rock and phosphate tailings.

TRANSESTERIFICATION OF TRIGLYCERIDES WITH PROPAN-2-OL CATALYSED BY SULFURIC ACID

Transesterification of sunflower oil triglycerides with propan-2-ol catalyzed by sulfuric acid has been studied. The effect of the homogeneous acid catalyst content and the triglycerides of sunflower oil : propan-2-ol molar ratio on the reagents conversion, selectivity of diisopropyl ether formation, the acid number and the color of reactions products on the iodine scale was determined. It was established that an increase in the sulfuric acid content from 1 wt. % up to 3 wt. % leads to a slight increase in the triglycerides conversion and a significant increase in the propan-2-ol conversion. A further increase in the acid catalyst content causes a decrease in the conversion of both triglycerides and alcohol. Comparison of the obtained results with the data on the reaction products composition allowed us to conclude that a significant increase in the propan-2-ol conversion with an increase in the sulfuric acid content to 3–4 wt. % due to the increase in the diisopropyl ether selectivity formation from 5% by an acid catalyst content of 1 wt. % to almost 65% by a sulfuric acid content of 4 wt. %. It is shown that an increase in the sulfuric acid content in the reaction mixture also leads to a significant increase in the reaction product's color according to the iodine scale - almost 5 times, which also indicates the course of side condensation reactions with the double bonds of higher fatty acids participation, which are part of triglycerides composition. It is established that the reaction product's acid number regularly increases with an increase in the acid catalyst content in the reaction mixture. It is shown that the reaction products acid number value is determined by the amount of acid catalyst used. It is established that the activity of the sulfuric acid in the sunflower oil triglycerides transesterification reaction is slightly lower than the activity of cation exchange resin KU-2-8. The cation exchange resin under the same conditions provides more than 15% higher triglycerides conversion with a lower reaction product's color on the iodine scale value and the absence of a diisopropyl ether formation side reaction. It is concluded that using sulfuric acid as a catalyst for triglyceride transesterification by propan-2-ol is entirely possible.

Enantioselective bio-deacylation of arylalkyl acetates using tertiary amines as additive under promiscuous conditions

Herein, we describe the impact of the introduction of tertiary amines as additive during the enzymatic kinetic resolution via deacylation of some arylalkyl acetates 1a-8a under promiscuous conditions. Two CAL-B preparations were examined: Novozym®435 and CHIRAZYME® L-2, c.-f. C2, lyo. The influence of the introduction of seven amines is checked: Triethylamine (Et3N), Pyridine, 4-Dimethylaminopyridine (4-DMAP), 1,4-Diazabicyclo[2.2.2]octane (DABCO), Cinchonine, Cinchonidine, Quinine and Quinidine; and that in two organic solvent: diisopropylether (DIPE) and tertiobutylmethyl ether (TBME).Among the examined amines, the use of DABCO as additive recorded the best results in terms of reactivity and selectivity. It was to be highlighted that this additive was reported as an enzyme activator for the first time in the enzymatic kinetic resolution via hydrolysis of racemic acetates under non-aqueous conditions. Both CAL-B preparations showed the same behavior in the presence of the chosen additives during the biodeacylation of the resolved acetates. No direct correlation between the pKa values of several used additives and the CAL-B activation rates has been revealed.An ideal enzymatic kinetic resolution was recorded with the acetate 4a (Conv 50% and E > >200).

Enhanced Isopropyl Alcohol Conversion over Acidic Nickel Phosphate-Supported Zeolite Catalysts.

In this preliminary research, the catalytic activity of isopropyl alcohol conversion to diisopropyl ether through dehydration reaction catalyzed by zeolite-Ni and zeolite-Ni(H2PO4)2 was comparatively described. The natural zeolite was treated with 1% HF and 6 N HCl prior to modifications using the impregnation method. Isopropyl alcohol conversion was examined at a mild temperature of 150 °C for 3.5 h on the reflux system with various catalyst loadings. X-ray diffraction and Fourier transform infrared analysis confirmed the successful impregnation of nickel and nickel phosphate into the zeolite. Scanning electron microscopy analysis revealed a cubic-like structure on zeolite-Ni(H2PO4)2, whereas homogenously distributed nickel species were observed on the zeolite-Ni catalyst. Energy-dispersive X-ray spectroscopy analysis reinforced the accomplishment of zeolite modifications. The N2 physisorption isotherms showed a decline in the surface area and total pore volume of the zeolite because of the blocking of pores. The zeolite-Ni(H2PO4)2 catalyst had higher acidity than unmodified zeolite and zeolite-Ni catalysts, which inherently suggested that the presence of phosphate groups results in higher catalytic activity toward isopropyl alcohol. The highest catalytic activity was attained by 8 mEq/g metal loading zeolite-Ni(H2PO4)2 with isopropyl alcohol conversion of 81.51%, diisopropyl ether yield, and selectivity of 40.77 and 33.16%. The reusability study suggested that the zeolite-Ni(H2PO4)2 catalyst was still active and had sufficient catalytic activity stability toward isopropyl alcohol after the third cycle was reused. This nickel phosphate-based modified zeolite was adequately potential for diisopropyl ether production through isopropyl alcohol dehydration.

A new ether-based medium-concentrated electrolyte for lithium–sulfur battery with lean Li anode

A new ether-based electrolyte with tetrahydrofuran (THF) and di-isopropyl ether (DIPE) is proposed for Lithium–Sulfur battery (LSB). By employing the common ion effect and the weakly-solvating solvent (such as DIPE), the dissolution of lithium polysulfides and the self-discharge effect are effectively inhibited. Besides, the LiFSI has be used as the co-salt in the LiTFSI-based electrolyte to improve the ionic conductivity and inhibit the side reaction on Li metal anode. It is worth mentioning that, the L1L2TD-1382 electrolyte (LiTFSI: LiFSI: THF: DIPE = 1 : 3: 8 : 2, molar ratio) ensures a stable cycling for more than 500 cycles with a high Columbic efficiency (CE) of Li deposition/stripping (>99.3%). Impressively, with selenium doped sulfurized polyacrylonitrile (SeSPAN) cathode, the Li–S cell has delivered a high capacity of 626 mAh g−1 in 500th cycle with an excellent capacity retention no less than 93%. This work provides a new insight to electrolyte design strategy of advanced electrolytes for Li–S batteries.

(Invited) Functionalized Water-Mimicking Ionic Liquids for Biocatalysis

Enzyme activity in organic solvents is usually much lower than its performance in aqueous media. To develop water-mimicking environment for the enzyme, we designed ionic liquids functionalized with tert-alcohol (as hydrogen-bond donor) and ether groups (as hydrogen-bond acceptors). These “water-like” ionic media have high thermal stability and low viscosities, and produced higher lipase and protease activities and stabilities than some enzyme-compatible organic solvents (such as tert-butanol and diisopropyl ether) and conventional ionic liquids (e.g., [BMIM][Tf2N]) during transesterification reactions under low water contents. In addition, these unique ionic solvents are found suitable media for asymmetric synthesis. Our experimental and MD simulations data illustrate the interactions between these water-mimicking solvent molecules and the enzyme.

Extracting phenolic compounds from aqueous solutions by cyclohexanone, a highly efficient extractant

Methyl isobutyl ketone (MIBK) and diisopropyl ether (DIPE) are two commonly used extractants in industry, but their efficiency in extracting phenols, especially polyhydroxyphenols, is low. In the work, a highly-efficient extractant was proposed to extract phenolic compounds, including polyhydroxyphenols. The interactions between three extractants, cyclohexanone (CYC), MIBK and DIPE, and phenols were analyzed by the COSMO-RS method and CYC shows stronger interactions with phenols than MIBK and DIPE. The results of Fourier-transform infrared spectroscopy (FTIR) show that strong hydrogen bonds are formed between CYC and phenolic compounds, in agreement with the results of the COSMO-RS method. The effects of concentration, temperature and pH values on the extractant performance were studied. Results showed that the performance of CYC is the best, followed by MIBK and DIPE, whose performance is the worst. As CYC was used as the extractant, the distribution coefficients of the three phenolic compounds, phenol, resorcinol and phloroglucinol, are 96.7, 47.8, 13.0, respectively. These values are 35%, 263%, and 160% larger than those of phenol, resorcinol and phloroglucinol, respectively, corresponding to MIBK. CYC is a highly-efficient extractant for the extraction of phenolic compounds, including polyhydroxyphenol.

Catalyst-Tuned Electrophilic Chlorination of Diverse Aromatic Compounds with Sulfuryl Chloride and Regioselective Chlorination of Phenols with Organocatalysts.

In this work, we demonstrate that diverse aromatic compounds can be selectively chlorinated through the fine-tuning of the reactivity of sulfuryl chloride (SO2Cl2) by organocatalysts. Acetonitrile has been identified to activate SO2Cl2 most strongly, thus enabling even chlorination of p-xylene with high yields. 1,4-Dioxane effects chlorination of oxidation-labile aromatic compounds such as p-cresol and 2-naphthol with high yields, 95% and 85%, respectively. An array of potential catalysts has been screened for ortho- and para-selective chlorination of phenols. Thus, we found that acetonitrile, (S)-BINAPO (5 mol %), and diisopropyl ether (4.00 equiv) can catalyze the chlorination of phenols in a para-selective manner (with ≤4:96 o:p ratio), whereas Nagasawa's bis-thiourea (1 mol %), phenyl boronic acid (5 mol %), and (S)-diphenylprolinol (1 mol %) exhibit high ortho selectivity [with ≤99:1 o:p ratio by (S)-diphenylprolinol].

Experimental investigation and performance prediction of gasoline engine operating parameters fueled with diisopropyl ether-gasoline blends: Response surface methodology based optimization

In this research, gasoline engine performance and emission characteristics were studied when powered by diisopropyl ether-gasoline blends. The main objective of this study is to determine the behavior of diisopropyl ether-gasoline blends at various engine speeds and compression ratios. Further, the engine parameters were optimized using the response surface methodology. Enriched oxygen, higher latent heat of vaporization, and the readily volatile nature of the fuel enhanced the brake thermal efficiency and lowered the hydrocarbons and carbon monoxide due to a better combustion rate. The developed model exhibited superior R2 values with a 0.957 desirability factor. The optimum parameters such as speed, compression ratio, and fuel-blend concentrations were found at 2250 rpm, 10:1, and D25 (75% gasoline and 25% diisopropyl ether), respectively. The responses for the optimal input parameters were brake thermal efficiency (31.53%), specific fuel consumption (0.2923 kg/kWh), carbon monoxide (0.14% by Vol.), hydrocarbons (31 ppm), and oxides of nitrogen (708 ppm). The predicted values for optimum engine parameters were validated with the experimental data, and their percentage of absolute error was found to be less than 5%. Thus, the study concludes that diisopropyl-ether gasoline blends can be used as an alternative fuel to enhance the brake thermal efficiency and reduce the pollution level, and the proposed numerical model can predict the responses with high accuracy.

Performance of PES Membrane Contactor on the Separation of Dilute Acetic Acid from Aqueous Forms

The azeotropic characteristics of acetic acid between water make its separation from its aqueous phase essential. Many methods are studied for separating such a mixture. Solvent extraction using membrane contactors can increase the contact surface area. The dilute aqueous acetic acid extraction with the solvents petroleum ether and diisopropyl ether in a Poly Ether Sulfone (PES) hollow fiber membrane contactor was studied. The solvents and membrane extraction abilities are evaluated by exchanging the fluids on the shell and tube sides based on the distribution coefficients and total mass transfer coefficient at various flow rates. The findings show that when the solvent flow is increased, whether on the shell side or the tube side, the concentration of acetic acid increases in its solvent phase. As the shell side Reynolds number increased, it was noticed that the distribution coefficient value also increased. Both solvents' extraction ability was minimal, but diisopropyl ether gave better results when compared with the petroleum ether in terms of distribution coefficient. Three film resistance parameters in the series model have determined the overall mass transfer coefficient. The Reynolds number values showed that the mass transfer occurs in a laminar zone. Changes in the petroleum ether's Reynolds number on the tube side resulted in a maximum mass transfer coefficient of 11.41x10-6 m/s. Data on such hydrodynamics studies on membrane solvent extraction can help recover value-added material studies.

A detailed high-pressure oxidation study of di-isopropyl ether

The oxidation of di-isopropyl-ether (DIPE) was studied in a jet-stirred reactor. Fuel-lean, stoichiometric, and fuel-rich mixtures (φ = 0.5–4) were oxidized at a constant fuel mole fraction of 1000 ppm, at temperatures ranging from 500 to 1160 K, at 10 atm, and constant residence time of 0.7 s. The chosen conditions are consistent with our previous studies on ether oxidation. Mole fraction profiles were obtained through sonic probe sampling, and analyzed by gas chromatography and Fourier transform infrared spectrometry. As opposed to our previous studies on ethers (S. Thion et al. 2017, Z. Serinyel et al. 2018 and 2020), DIPE showed no low-temperature reactivity under the same experimental conditions. Oxidation of the rich mixture showed similarities to pyrolysis producing important quantities of propene and isopropanol, while no isopropanol is observed under lean conditions. In terms of overall reactivity, DIPE showed smaller fuel conversion compared to other symmetric ethers previously studied. The present data and literature experiments were simulated with our ether oxidation mechanism showing good agreement.

Sevoflurane analysis in forensic cases using headspace-gas chromatography-mass spectrometry: A case study

The objective is to present a case study related to forensic analysis of Sevoflurane Using Head Space (HS)-GCMS. For qualitative detection of volatile substances, this methodology might be helpful in conducting forensic analysis of such substances. Sevoflurane is an ether inhalation general anaesthetic agent. Sevoflurane is a volatile nonflammable fluorinated methyl isopropyl ether inhaled anaesthetic, chemically related to desflurane and isoflurane (C. M. Rosales, J. Forensic Sci., 2007, 52, 1408–1410). The low solubility and the absence of pungency facilitate rapid mask induction. It has been used as an inhaled anaesthetic since 1985. Its major distribution is initially to areas of high blood flow (brain, heart, liver and kidney) and later to less perfused organs. Sevoflurane can cause cardio-respiratory depression, hypotension, and malignant hyperthermia (M. Adachi, J. Anaesth., 1992, 68, 214–215). Seizures (convulsions) can occur during anaesthesia with Sevoflurane but Sevoflurane related deaths are rare. Various studies have been conducted for detection and quantification of Sevoflurane in postmortem and toxicological studies. The case was submitted at PFSA (Punjab Forensic Science Agency) for analysis consisting of bottle of suspected narcotics. The bottle was recovered from accused committing offence of criminal intimidation, life threat and physically assaulting his ex-wife and children. He trespassed into house and sprayed her with some bottle in order to molest her. He also threatened her children and his father in-law with pistol. The suspected bottle of spray was analyzed qualitatively using HS-GC-MS with slight modification in already validated method. About 1–2 mL of liquid was taken in headspace vial and heated up to 50–60oC (for vaporization) and about 1–2 μL of headspace sample was injected manually in GC. A gas chromatographic system 7890B series (Agilent Technologies, Palo Alto, CA, USA) coupled to MS detector. Agilent HP-5MS Ultra Inert column (30 m length, 250 μm ID, with film thickness of 0.25 μm) (D. Bourdeaux, J. Chromatogr. B. Analyt. Technol. Biomed. Life Sci., 2010, 878, 45–50). was used for the separation of constituents. Injection volume of 1 μL was used in split mode in 20:1 ratio at 250 °C. Helium gas was used as carrier gas with 1 mL/min flow rate with inlet pressure 12.051 psi. Oven temperature for GC column at 50 °C upheld for 2 min and then gradually increased to 150 °C at 50 °C/min for 1 minute. The total run time was set up for 5 min. The temperature for MS source and MS Quad were 230 °C and 150 °C respectively. Scan mode for m/z from 43–220 was done. Agilent GC Chemstation was used for data analysis. Results were compared with reference book (C. Maffat, Clark's Analysis of Drug and Poisons. 3rd. London-Chicago: Pharmaceutical Press, 2004, 2, 1558–1559). This exceptional crime case of using sevoflurane bottle for threatening and attacking received in our lab was evaluated for the presence of suspected drug. The sample analyzed using HS-GCMS showed a single peak on chromatogram at 1.282 + 0.01 minutes and the MS ions were matched with reference MS spectrum showing Sevoflurane which is being used as inhalation anaesthetic. Various studies suggested that Sevoflurane could possible cause irreversible circulatory depression and hypoxia and may cause death. It is the new case of decapitation with sevoflurane. The reported method is quite short and efficient in detection of Sevoflurane using HS-GCMS.

Energy-Efficient Hybrid Reactive-Extractive Distillation with a Preconcentration Column for Recovering Isopropyl Alcohol and Diisopropyl Ether from Wastewater: Process Design, Optimization, and Intensification

Energy-Efficient Hybrid Reactive-Extractive Distillation with a Preconcentration Column for Recovering Isopropyl Alcohol and Diisopropyl Ether from Wastewater: Process Design, Optimization, and Intensification

Effects of Different Gasoline Additives on Fuel Consumption and Emissions in a Vehicle Equipped With the GDI Engine

Fuel additives are considered to be a cost-effective and simple approach to improve combustion and reduce the harmful emissions of internal combustion engines. In addition to the use of conventional fuel additives, some unconventional fuel additives also have potential to improve fuel properties. Exploring the effects of different unconventional additives can provide a valuable reference to improve vehicle performance by fuel optimization. In this study, five unconventional gasoline additives (i.e., isopropyl ether, aniline, diethylamine, dimethyl malonate and p-tert-butylphenol) were blended with the baseline gasoline (G92). The five blended fuels are referred to as G92-1, G92-2, G92-3, G92-4, and G92-5, respectively. Fuels with different additives were tested on a compact passenger vehicle with a 1.4-L gasoline direct injection engine to assess the effects of these additives on performance and emission characteristics, and G92 gasoline was compared as a baseline. The new European drive cycle (NEDC), which is representative for passenger car and light duty vehicles, was chosen in the tests. The experimental results show little or slight improvement in fuel consumption for fuels blended with additives. With respect to gaseous emissions, the vehicle obtains the lowest and highest NOx emissions by fueling G92-5 (blended with p-tert-butylphenol) and G92-3 (blended with diethylamine), respectively; the lowest and highest CO emission is acquired using G92-2 (blended with aniline) and G92-4 (blended with dimethyl malonate), respectively; the vehicle reaches the lowest and highest THC emissions when fueling G92-3 (blended with diethylamine) and G92-4 (blended with dimethyl malonate), respectively; and the lowest and highest CO2 emission using G92-3 (blended with diethylamine) and G92-2 (blended with aniline), respectively. Compared with the baseline gasoline fuel, all of the fuels with additives show improved engine-out PM emissions. Furthermore, all five additives can improve the acceleration performance slightly. In brief, diethylamine is potential gasoline additive to reduce carbon emissions, improve fuel consumption, and enhance performance.

Measurement of the Density and Viscosity of Diisopropyl Ether and 1-Alkanol Mixtures at Various Temperatures

Measurement of the Density and Viscosity of Diisopropyl Ether and 1-Alkanol Mixtures at Various Temperatures

Single‐Crystal‐to‐Single‐Crystal Transformation and Alcohols Enantioseparation of Homochiral Ir(III)‐Metallohelix‐Based Porous Molecular Crystal

AbstractSingle‐crystal‐to‐single‐crystal (SCSC) transformations of porous crystals have been proved as an important platform for creating new materials. The current study describes porous molecular crystal with two different polymorphs based on the same chiral helicate modules can be controllably obtained when simply changing the crystallization solvents from diethyl ether to isopropyl ether. Interestingly, the β‐polymorph can also be effective obtained through SCSC transformations from α‐polymorph in solid state using isopropanol as a trigger. Compared with our reported α‐polymorph, the newly obtained β‐polymorph porous molecular crystal displays higher CO2 uptake and better selectivity for CO2 over N2 at 298 K. Meanwhile, as chiral solid adsorbents, both of β‐polymorph and α‐polymorph exhibit similar enantioselective separation abilities towards alcohols but different adsorption kinetics.

Size-Induced Highly Selective Synthesis of Organometallic Rectangular Macrocycles and Heterometallic Cage Based on Half-Sandwich Rhodium Building Block.

The controlled synthesis of organometallic supramolecular macrocycles cages remains interesting and challenging work in the field of supramolecular chemistry. Here, two tetranuclear rectangular macrocycles and an octuclear cage were designed and synthesized utilizing a rigid and functionalized pillar linker, 2,6-bis(pyridin-4-yl)-1,7-dihydrobenzo [1,2-d:4,5-d′]diimidazole (BBI4PY) based on three half-sandwich rhodium building blocks bearing different sizes. X-ray crystallography in combination with 1H NMR spectroscopy elucidated that the two building blocks with shorter spacers only result in rectangular macrocycles. However, the building block of bulkier size to avoid the π-π stacking interactions between two ligands BBI4PY led to the formation of an octuclear cage complex. The latter cage contains two types of metal ions, namely Rh3+ and Cu2+, showing significant characteristics of heterogeneous metal-assembling compounds. In addition, the cage accommodates two free isopropyl ether solvent molecules, thus displaying host–guest behavior.

The influence of substrate systems on the enantioselective and lipolytic activity of immobilized Amano PS from Burkholderia cepacia lipase (APS-BCL)

In this study, Amano lipase PS from Burkholderia cepacia (APS-BCL) was immobilized onto polyacrylic support IB-150A, which allowed to improve immobilized lipase activity in nonaqueous media compared with the free (native) form. The enantioselectivity of the immobilized APS-BCL (8 mg/mL) in the kinetic resolution of (R,S)−1-phenylethanol was evaluated. High values of catalytic parameters with isopropenyl acetate (E =775.4, C =49 % ± 0.4) and vinyl acetate (E =206.6, C = 50 % ± 0.3) as acyl donors were achieved after a reaction time of 12 h. The effects of 7 different non-aqueous solvents on catalyst enantioselectivity in the kinetic resolution of (R,S)−1−phenylethanol were also assessed. Diisopropyl ether and n-hexane were selected as the optimal reaction media. A novel lipolytic activity study of immobilized APS-BCL (7.9–9.3 mg/mL) with the application of the developed multicomponent unsaturated fatty acids (MC-UFAs) method using 13 vegetable oils in an aqueous medium has been proposed (pH =7, T =37 °C). The effect of the ratio of polyunsaturated fatty acids (PUFAs) to monounsaturated fatty acids (MUFAs) on lipase activity was demonstrated and a cut-off limit (ω6/ω9 =2.3) was determined. Hyperactivation of immobilized APS-BCL in peanut oil (Arec=104.85 %, Aret=110.19 %) as the substrate was observed.