Glycerolysis Reaction Research Articles

Evaluation on potential application of lipase immobilized on rice husks in enzymatic glycerolysis reaction

Owing to high production cost and low reaction yield, immobilized lipase is rarely used in industrial glycerolysis. This research characterizes the performance of lipase immobilized on rice husk in glycerolysis reaction. By utilizing hexamethylenediamine (HMDA) and glutaraldehyde (GA) as coupling agents, lipase from Thermomyces lanuginosus was immobilized on oxidized rice husk (ORH). For comparison, another sample was prepared where the lipase was directly immobilized on ORH without the use of HMDA and GA. Then, monoglyceride production was performed via glycerolysis using the immobilized lipase. The FTIR analysis verify interactions on rice husk including rice husk oxidation, HMDA coupling, GA activation and lipase immobilization on rice husk. The study found that within the examined range of added lipase for immobilization (10–40 mg-protein/g-support), ORH–HMDA–GA–Lipase possessed superior outcomes in terms of protein loading, immobilization yield, and recovered glycerolysis activity compared to ORH–Lipase. Besides, ORH–HMDA–GA–Lipase exhibits better storage stability (60°C, 44.9 %) and higher reusability (90.0 % monoglyceride yield at the 8th cycle) against ORH–Lipase. The results confirm satisfying performance of the prepared immobilized lipase in glycerolysis and highlight its enhancements facilitated by coupling agents.

Enzymatic preparation of diacylglycerols: lipase screening, immobilization, characterization and glycerolysis performance.

Glycerolysis, with its advantages of readily available raw materials, simple operation, and mild reaction conditions, is a primary method for producing diacylglycerol (DAG). However, enzymatic glycerolysis faces challenges such as high enzyme costs, low reuse efficiency, and poor stability. The study aims to develop a cost-effective immobilized enzyme by covalently binding lipase to pre-activated carriers through the selection of suitable lipases, carriers, and activating agents. The optimization is intended to improve the glycerolysis reaction for efficient DAG production. Lipase CN-TL (from Thermomyces lanuginosus) was selected through glycerolysis reaction and molecular docking to catalyze the glycerolysis reaction. Optimizing the immobilization method by covalently binding CN-TL to poly(ethylene glycol) diglycidyl ether (PEGDGE)-preactivated resin LX-201A resulted in the preparation of the immobilized enzyme TL-PEGDGE-LX. The immobilized enzyme retained over 90% of its initial activity after five consecutive reactions, demonstrating excellent reusability. The DAG content in the product remained at 84.8% of its initial level, further highlighting the enzyme's potential for reusability and its promising applications in the food and oil industries. The immobilized lipase TL-PEGDGE-LX, created by covalently immobilizing lipase CN-TL on PEGDGE-preactivated carriers, demonstrated broad applicability and excellent reusability. This approach offers an economical and convenient immobilization strategy for the enzymatic glycerolysis production of DAG. © 2024 Society of Chemical Industry.

Solvent-free synthesis of diacylglycerols via enzymatic glycerolysis between edible oils and glycerol catalyzed by self-made immobilized lipase PS@LXTE-1000

Diglycerol (DAG) is a structural lipid with the functions to lower body fat accumulation and decrease serum triglyceride level. However, the enzymatic synthesis of DAG is limited by the high-efficient and economic lipases. In this paper, the immobilized lipase PS@LXTE-1000 was self-made by immobilizing the Pseudomomas cepacian lipase on to the hydrophobic microporous resin LXTE-1000. The results indicate that LXTE-1000 was a uniform mesoporous sphere with the mean diameter of 400 ​μm, pore size of 14.6 ​nm, pore volume of 0.5 ​cm3/g and surface area of 126.0 ​m2/g, showing superior structural properties for lipase immobilization. Under the optimal reaction conditions with the molar ratio of rapeseed oil to glycerol being 1:1, adding amount of immobilized lipase being 4%, reaction at 50 ​°C, the highest DAG content of 46.7% was achieved in 3 ​h via enzymatic glycerolysis catalyzed by LXTE-1000. After 7 cycles of reuse, the self-made LXTE-1000 could still retain 78.3% of its initial catalytic ability. Besides, LXTE-1000 was observed to facilitate the DAG production via glycerolysis reaction between glycerol with other seven edible oils including corn oil, sesame oil, peony seed oil, rice bran oil, peanut oil, soybean oil and flaxseed oil. Specifically, the glycerolysis reaction with sesame oil, peony seed oil and rice bran oil even led to the DAG content of 52.1%, 53.3% and 51.2%, respectively, Hence, this paper provide a novel strategy to produce high-efficient and economic immobilized lipases, which shows great potential in the green synthesis of functional lipids such as DAG.

Immobilization of Lipase from Thermomyces Lanuginosus and Its Glycerolysis Ability in Diacylglycerol Preparation.

In the glycerolysis process for diacylglycerol (DAG) preparation, free lipases suffer from poor stability and the inability to be reused. To address this, a cost-effective immobilized lipase preparation was developed by cross-linking macroporous resin with poly (ethylene glycol) diglycidyl ether (PEGDGE) followed by lipase adsorption. The selected immobilization conditions were identified as pH 7.0, 35 °C, cross-linking agent concentration 2.0%, cross-linking time 4 h, lipase amount 5 mg/g of support, and adsorption time 4 h. Enzymatic properties of the immobilized lipase were analyzed, revealing enhanced pH stability, thermal stability, storage stability, and operational stability post-immobilization. The conditions for immobilized enzyme-catalyzed glycerolysis to produce DAG were selected, demonstrating the broad applicability of the immobilized lipase. The immobilized lipase catalyzed glycerolysis reactions using various oils as substrates, with DAG content in the products ranging between 35 and 45%, demonstrating broad applicability. Additionally, the changes during the repeated use of the immobilized lipase were characterized, showing that mechanical damage, lipase leakage, and alterations in the secondary structure of the lipase protein contributed to the decline in catalytic activity over time. These findings provide valuable insights for the industrial application of lipase.

Sustainable polyurethane coatings derived from alkyds of Camelina oil monoglycerides

AbstractThis study presents the synthesis of sustainable urethane coatings derived from alkyds of Camelina oil (CO) monoglycerides, offering a sustainable alternative to petrochemical resources. Utilizing immobilized lipase for a low‐temperature glycerolysis reaction, high‐yield monoglycerides were obtained from CO. These were then reacted with dibasic acids (phthalic, succinic, and maleic anhydride) to produce alkyd diols, confirmed by both nuclear magnetic resonance (NMR) and Fourier transform infrared (FTIR) spectroscopy. The hydroxyl functionality of the alkyd diols showed a significant enhancement (up to 2200%) over crude CO produced Camelina‐based alkyd diols were incorporated into polyurethane formulations and applied to metal substrates. Comprehensive performance evaluations revealed their superior mechanical, thermal, and chemical properties in comparison with previously reported plant‐based alkyd‐urethane coatings, especially for the phthalic anhydride‐derived alkyd diol. The present research underscores the potential of Camelina‐derived alkyds in creating high‐performance, plant‐based coatings, aligning with recent sustainability trends in material science.

Valorization of straw biomass into lignin bio-ink, bacterial cellulose and activated nanocarbon through the trade-off alkali-catalyzed glycerol organosolv biorefinery

Integrated lignocellulosic biorefinery that transforms low-value lignocellulose into multiple value-added products is crucial for a low-carbon sustainable development. Herein, a one-pot alkali-catalyzed glycerol organosolv (ALGO) pretreatment-based integrated biorefinery process to directionally produce lignin bio-inks, bacterial celluloses (BCs), and activated nanocarbons (ANCs) was proposed. ALGO pretreatment could modify the structure of dissolved lignins by glycerolysis. The extracted lignin fragments with high-purity (>90 %), uniform with low molecular weight (2500–4000 of Mw), and abundant hydrophilic aliphatic –OH were promising candidates in 3D-printable inks preparation. The glycerolysis reaction during ALGO process also enabled pretreated substrates toward high hydrolyzability and protected pretreatment liquor from generating fermentable inhibitors, making the solid fractions more liable for enzymatic deconstruction and microbial fermentation. Without any detoxification treatments, hydrolysates from ALGO pretreated substrates were used directly as carbon sources for BCs production, resulting in the BC yields were 56 % higher than that of the commercial glucose. The enzymatic hydrolysis residue and BC fermentation waste liquid were synthesized into ANCs via a facile carbonization process, which could further increase the value of ALGO biorefinery. Calculations showed that this ALGO integrated strategy rendered the conversion of ∼75 % lignins in pretreatment liquor to bio-inks and nearly 100 % solid fractions to BCs and ANCs. Unlike the conventional “lignin-first” route to obtain high-purity cellulose by sacrificing the value-adding conversion ability of by-products, the designed technical route in this work achieved a good trade-off between fractionation ability and subsequent conversion potential, inspiring further exploration of the technical correlation between biomass fractionation and bioproduct processing.

Glycerolysis of palm kernel oil catalized by MgO on mono and diglyceride composition and their antibacterial activity

Monoglyceride and diglyceride are known as emulsifiers that have been used in the food industry. Furthermore, both mono and diglyceride also have the potential to be utilized as antibacterial compounds. Both of them can be produced from natural source, such as palm kernel oil, via glycerolysis reaction. This study aims to determine the effect of temperature and time of glycerolysis reaction on the composition of mono and diglyceride and their capability as an antibacterial agent. This study used a split-plot design with the temperature of glycerolysis as the main plot (80°C, 90°C, and 100°C) and the time of glycerolysis as the subplot (3, 4, and 5 hours). Several parameters were analyzed, including acid value, percent conversion, and antibacterial activity. Then, Gas Chromatography-Mass Spectrometry (GC-MS) was used to analyze glycerolysis products. Our results showed that the variations in temperature and time of glycerolysis had no effect on acid numbers, percentage conversion, and antibacterial activity. In addition, the glycerolysis products have a higher zone of inhibition against Bacillus subtilis compared to Escherichia coli. The highest percentage of conversion was obtained at glycerolysis temperature of 100°C and 5 hours. From the results of GC-MS analysis, monolaurin was obtained at 12.06 percent area.

Emulsifier Dari Minyak Pliek U Dengan Reaksi Gliserolisis Menggunakan NButanol Sebagai Co-Solvent Dan Katalis MgO

Emulsifiers or emulsifying agents are one of the oleochemical products that have high economic value. One of the alternative ingredients that can be used as emulsifiers is Aceh palm oil (pliek u oil). In this study n-Butanol solvent is used which can increase the solubility of oil in glycerol so that the glycerolysis reaction can be carried out at low temperatures. This study aims to determine the effect of temperature and solvent ratio on the emulsifier produced. The catalyst used in the reaction is MgO (4% of oil weight), where the test variables used are reaction temperature (70, 80, 90, and 100◦C), 2 hours contact time, and the ratio of n-butanol to oil ( 1: 1, 1: 2, 1: 3 and 1: 4 v / v). The analysis was carried out in the form of an analysis of decreased levels of free fatty acids (ALB) by acid-base titration and Hydrophilic Lipophilic Balance (HLB) analysis to determine the type of emulsifier produced. The results showed that the greatest decrease in free fatty acid levels was found in the solvent to oil ratio of 1: 4 (v / v), and the temperature of 100◦C was 91.26%. The resulting HLB value of 19.68 is categorized into oil in water (o / w). The results obtained from this study indicate that pliek oil can be used as raw material for making emulsifiers using n-Butanol solvent and MgO catalyst.

Synthesis of glycerol carbonate from industrial by-products by alcoholysis of urea: Crude glycerol and red gypsum

In this study, a heterogeneous catalyst was developed from red gypsum for the synthesis of glycerol carbonate through a glycerolysis reaction with urea. Under optimum reaction conditions, a simple heat treatment on bare red gypsum in a static air environment produces an 87% yield of the targeted glycerol carbonate product. The higher catalytic activity of the calcined catalyst is due to its basic characteristics and the presence of different phases of anhydrite CaSO4 with additional elements, especially an active hematite (Fe2O3) phase. The catalytic process was also found to be insensitive to the type of flowing gas that was used to remove the evolved ammonia gas, whereby, either inert nitrogen gas or reactive air containing oxygen did not significantly impact the glycerol carbonate yield. Indeed, with a promising yield, the developed catalytic system was able to directly synthesise glycerol carbonate from industrial crude glycerol from a biodiesel plant. The red gypsum-based catalytic system seems resistant to the presence of a certain level of moisture and other impurities in crude glycerol. The catalyst efficiency is being retained for consecutive reaction cycles, which are subsequently reused for the next batch reaction without requiring any pre-treatment.

Improving the technology of the synthesis of fatty acid monoglycerides using the glycerolysis reaction

The object of research is the process of fat glycerolysis in order to obtain fatty acid monoglycerides. Monoglycerides are an important component of chemical, pharmaceutical, cosmetic, and food industry products. These substances are used as emulsifiers, structure formers, complex formers, etc. The industrial production of monoglycerides involves the use of complex technologies, as well as dangerous and unstable catalysts. An urgent task is to develop new catalysts and improve technologies for monoglycerides obtaining. The technology for the synthesis of monoglycerides by the glycerolysis method, which involves the reaction of vegetable hydrogenated fat with glycerol, was studied. Potassium glyceroxide was used as a catalyst, which is effective and safe in terms of production and use. Hydrogenated unrefined fat according to DSTU 5040 (CAS Number 68334-28-1) was used. The fat has non-standard parameters: the melting point is 51 °C, the mass fraction of moisture and volatile substances is 0.3 %, the acid value is 3.2 mg KOH/g, the peroxide value is 7.6 ½ O mmol/kg. The process duration was 90 minutes, the glycerol concentration was 50 %. Rational conditions for glycerolysis were determined: catalyst concentration (1.5 %) and temperature (140 °C). Under these conditions, the product ensured the stability of the “water – sunflower oil” emulsion of 96.8 %, the concentration of monoglycerides in the system was 0.1 %. Product parameters: mass fraction of monoglycerides – 72.5 %, free glycerol – 1.5 %, acid value – 1.7 mg KOH/g. The research results make it possible to improve the glycerolysis process using a new catalyst and obtain monoglycerides with high emulsifying ability. This will increase the profitability of the enterprise and increase the volume of production of high-quality monoglycerides for various industries

Immobilization of Lecitase® Ultra for production of flaxseed oil-based diacylglycerols by glycerolysis and its operational stability

Lecitase® Ultra (LU) was immobilized by adsorption on a macroporous resin and characterized. Meanwhile, the obtained immobilized lipase LXTE-1000-LU was applied in diacylglycerol (DAG) preparation, and the glycerolysis catalytic stability was also investigated. At pH 7.0, resin amount 2.5 g, and adsorption time of 2 h, an immobilization efficiency (IE) of 89.98% could be achieved. The storage stability was promoted after immobilization, in which the lipase activity reached more than 85% after 60 days of storage at 4 °C and 25 °C individually compared to its initial state. Furthermore, 41.31% of flaxseed oil-based DAG was obtained after the glycerolysis reaction using LXTE-1000-LU as the catalyst. Under prolonged reaction, the lipase protein content decreased from 17.91 mg/g to 6.99 mg/g, and significant changes in the secondary confirmation of the protein were also observed, leading to the catalytic activity being reduced.

Glycerolysis of high free fatty acid oil by heterogeneous catalyst for biodiesel production

The most widely used commercial biodiesel production technique, alkali-catalysed transesterification, requires only moderate temperatures and pressures to achieve a more than 98% conversion yield. Unfortunately, oil feedstock's high free fatty acid (FFA) content limits the technology's usefulness. A heterogeneous base catalysed glycerolysis process was investigated in this study to lower the FFA and meet these requirements. The response surface methodology (RSM) based on I-optimal design was used to model and optimize a CaO catalysed glycerolysis reaction under the influence of five reaction variables: temperature (60–180 °C), residence time (30–120 min), FFA concentration (6–50%), catalyst amount (0.4–0.6 wt (g/g)), and Glycerol to Oil ratio (G/O) (1–1.5). The data were fitted in a quadratic model, and R2 of 0.986 was observed, signifying that the model well defined the experimental data. The model was validated by running four replicates of the experiment, and a residual standard error of 2.7% was obtained, indicating the model would accurately predict future observations. The 48.584% FFA in oil was reduced to 0.98% under optimal conditions of 170 °C, 39.9 min of residence time, 0.591 wt g catalyst concentration, and 1.026 g/g glycerol/oil (G/O) ratio. CaO catalysed glycerolysis has significantly reduced FFA to less than 3% in less than an hour in biodiesel feedstock for biodiesel production.

The utilization of natural deep eutectic solvent composition in tocotrienol and tocopherol extraction from crude palm oil and its acylglycerol products

Vitamin E is the largest phytonutrient in crude palm oil (CPO) which comprises isomers, tocopherols and tocotrienols. In this study, natural deep eutectic solvent (NADES), an alternative to organic solvent in the extraction of various bioactive compounds, was used to extract vitamin E from CPO. Three types of CPO, including CPO, CPO-rich diacylglycerol (CPO-DAG), and monoacylglycerol (CPO-MAG), were used to analyze the effect of acylglycerol composition in this extraction. The modified CPOs were obtained through a lipase-catalyzed glycerolysis reaction. The extraction used choline chloride-based NADES combined with acetic acid (ChCl-AA), oxalic acid (ChCl-OA), and citric acid (ChCl-CA) by creating a two-phase system between NADES and oils. The result shows that CPO: ChCl-AA yielded the highest vitamin E concentration (4439 mg/kg) and extraction efficiency (74.98%). Furthermore, CPO: ChCl-AA selectively separated tocotrienols, producing the tocotrienol-rich fraction (TRF). The ChCl-AA was then chosen to be used in CPO-DAG and CPO-MAG. The TRF concentrations in CPO-DAG and CPO-MAG were 3539.87 and 627.22 mg/kg, respectively. The ChCl-AA was the best combination for TRF extraction in CPO because CPO-DAG and CPO-MAG have free hydroxyl groups that hinder the hydrogen bond formation between NADES and tocotrienol molecules.

A Thermodynamic Analysis of Glycerol Monostearate Production by Glycerolysis

Thermodynamic analysis was performed on the reaction producing glycerol monostearate (GMS) from glycerol and stearic acid to examine the reaction's feasibility. Generation of GMS by glycerolysis of glycerol with stearic acid or fatty acids is thermodynamically advantageous in accordance with the equilibrium constant, K. Thermodynamic analysis was carried out to determine the parameters that affect the glycerolysis reaction using MATLAB 2014A and Microsoft Excel 2013. The obtained values of ΔHro; ΔSroand ΔGro were + 45.69 kJ/mol; +1.144 kJ/mol.K and –1.074 kJ/mol. Equilibrium constants at 433.15 K, 453.15 K, and 473.15 K for this synthesis were favourable, at 5.76 x 1024, 1.43 x 1027 and 2.23 x 1029, respectively. The higher the temperature, the greater the value of ln K, which suggests a limitless equilibrium. The largest yield of the substances involved in the reaction was obtained at 473 K with C3H8O3 (0.2286 mol), C18H36O2 (0.0620 mol), C21H42O4 (0.4379 mol) and H2O (0.27131 mol). Negative ΔGro values for this reaction suggest that formation of glycerol monostearate (C21H42O4) was plausible and feasible, and the formation of reaction products at equilibrium was highly favoured. This prediction provides an overview of the reaction to ensure an optimal yield of glycerol monostearate.

Encapsulation of lipases by nucleotide/metal ion coordination polymers: enzymatic properties and their applications in glycerolysis and esterification studies.

In the present study, lipases of TLL (lipase from Thermomyces lanuginosus), AOL (lipase from Aspergillus oryzae), RML (lipase from Rhizomucor miehei), BCL (lipase from Burkholderia cepacia), CALA (Candida antarctica lipase A) and LU (Lecitase® Ultra) were encapsulated into nucleotide-hybrid metal coordination polymers (CPs). Enzyme concentration was optimized for encapsulation and the enzymatic properties of the obtained lipases were investigated. In addition, their performance in glycerolysis and esterification was evaluated, and glycerolysis conditions (water content, temperature and time) were optimized. Hydrolysis activity over 10 000 U g-1 and activity recovery over 90% were observed from AOL@GMP/Tb, TLL@GMP/Tb and RML@GMP/Tb. GMP/Tb encapsulation (of AOL, TLL, RML and LU) improved their thermostability when incubated in air. The encapsulated lipases exhibited moderate [triacylglycerols (TAG) conversion 30-50%] and considerable glycerolysis activity (TAG conversion over 60%). TAG conversions from 69.37% to 82.35% and diacylglycerols (DAG) contents from 58.62% to 64.88% were obtained from CALA@GMP/metal samples (except for CALA@GMP/Cu). Interestingly, none of the encapsulated lipases initiated the esterification reaction. AOL@GMP/Tb, TLL@GMP/Tb, RML@GMP/Tb and CALA@GMP/Tb showed good reusability in glycerolysis, with 88.80%, 94.67%, 89.85% and 78.16% of their initial glycerolysis activity, respectively, remaining after five cycles of reuse. The relationships between temperature and TAG conversion were LnV0 =6.5364-3.7943/T and LnV0 =13.8820-6.4684/T for AOL@GMP/Tb and CALA@GMP/Tb, respectively; in addition, their activation energies were 31.55 and 53.78 kJ mol-1 , respectively. Most of the present encapsulated lipases exhibited moderate and considerable glycerolysis activity. In addition, AOL@GMP/Tb, TLL@GMP/Tb, RML@GMP/Tb and CALA@GMP/Tb exhibited good reusability in glycerolysis reactions and potential in practical applications. © 2022 Society of Chemical Industry.

Immobilization of <i>Candida antarctica</i> Lipase A onto Macroporous Resin NKA-9: Esterification and Glycerolysis Performance Study

In this study, lipase A from Candida antarctica (CALA) was immobilized onto the macroporous resin NKA-9. Immobilization conditions (pH, time and CALA concentration) were studied, enzymatic activity and immobilization efficiency (IE) up to 968.89 U/g and 53.19% were respectively obtained under optimal conditions (immobilization pH 5.0, time 5 h and CALA concentration at 30 mg/mL). Then, the NKA-9 supported CALA (CALA@NKA-9) samples were used to catalyze glycerolysis in solvent-free system. With 0.25 g of the present CALA@NKA-9 (soybean oil 3.52 g and glycerol 0.184 g) and after 12 h reaction at 50 °C, diacylglycerols (DAG) content up to 64.37% and triacylglycerols (TAG) conversion at 83.33% were obtained. The relationship between temperature and TAG conversion was LnV 0 = 13.9310-6.4212/T for CALA@NKA-9. Meanwhile, the activation energy (Ea) of CALA@NKA-9 was calculated to be 53.39 kJ/mol. In addition, reusability in the glycerolysis reaction was also evaluated, and 57.82% of the initial glycerolysis activity was retained after 9 consecutive applications. Furthermore, the CALA@NKA-9 was also used to catalyze the esterification (esterification of fatty acids with glycerol), however, the present CALA@NKA-9 cannot initiate the esterification. Therefore, the present CALA@NKA-9 is shown to be potential for DAG production through glycerolysis reaction.

Encapsulation of CALB by nucleotide/metal ions coordination nanoparticles: highly selective catalysis of esterification while poor performance in glycerolysis reaction.

Enzymatic esterification is attracting for particular high-acid oil deacidification. In this study, Candida antarctica lipase B (CALB) was encapsulated into a series of nucleotide-hybrid metal coordination polymers (CPs), which were constructed by guanosine 5'-monophosphate (GMP) and various metals. We here found that, most of the present CPs encapsulated CALB (CALB@CPs) samples were highly selective for esterification while poor in glycerolysis reaction. They exhibited quite poor performance in glycerolysis, with triacylglycerols (TAGs) conversion lower than 5%, despite this considerable enzymatic hydrolysis activities were observed. However, they (most of them) showed good performance in esterification of fatty acids and glycerol for TAG synthesis. In addition, the GMP/Tb (CPs constructed by GMP and Tb3+ ) encapsulated CALB (CALB@GMP/Tb) transformed over 98% of oleic acid into glycerides in the high-acid oil deacidification process, and TAG content from 87 to 89% was obtained. Moreover, the CALB@GMP/Tb showed good reusability in the esterification system. The present CALB@CPs samples are selective for esterification and suitable for high-acid oils deacidification. This work provides a new system for enzymatic selectivity improvement study. © 2021 Society of Chemical Industry.

Rendering waste oil as a new source for the synthesis of emulsifier: optimization, purification, and characterization

Abstract The enzymatic glycerolysis conditions in the production emulsifier by using the rendering waste oil were optimized in the present study. The effects of changes in duration (1–27 h), temperature (50–80 °C), enzyme (5–20%), and glycerol (5–20%) concentration, addition of solvent (acetone, acetonitrile, chloroform, methanol, ethanol, and tert-butanol) and water addition (3.5% of glycerol rate), and ultrasound application on the enzymatic glycerolysis reaction medium for mono- and diglyceride production were investigated. After determining the optimum conditions, the effects of the ultrasonic bath on the physic-chemical and rheological properties of emulsifier, the oxidation tests were examined. Using the preparative column chromatography method, three different emulsifier compositions were achieved and named E100, E50-50, and E50-40-10 by their monoglyceride, diglyceride, and triglyceride contents, respectively. Then, the post-purification emulsion properties and rheological behaviors of emulsifier samples were determined. E50-40-10 emulsifier was found to be the best sample in terms of rheological properties and emulsion stability.

Continuous production of monoacylglycerol via glycerolysis of babassu oil by immobilized Burkholderia cepacia lipase in a packed bed reactor.

This study investigated the glycerolysis of babassu oil by Burkholderia cepacia lipase immobilized on SiO2-PVA particles in a continuous packed bed reactor. Experiments were conducted in a solvent-free system at 273.15K either in an inert atmosphere or in the presence of cocoa butter to prevent lipid oxidation. The reactor (15 × 55mm) was run at a fixed space time of 9.8h using different molar ratios of babassu oil to glycerol (1:3, 1:6, 1:9, 1:12, and 1:15) to assess the effects of reactant molar ratio on monoacylglycerol productivity and selectivity. Nitrogen atmosphere and cocoa butter were equally effective in inhibiting lipid oxidation, indicating that addition of cocoa butter to glycerolysis reactions may be an interesting cost-reduction strategy. An oil/glycerol molar ratio of 1:9 resulted in the highest productivity (52.3 ± 2.9mgg-1h-1) and selectivity (31.5 ± 1.8%). Residence time distribution data were fitted to an axial dispersion model for closed-vessel boundary conditions, giving a mass transfer coefficient (kc) of 3.4229 × 10-6ms-1. A kinetic model based on elementary steps of the studied reaction was written in Scilab and compared with experimental data, providing standard deviations in the range of 5.5-7.5%.

Lipase-produced omega-3 acylglycerols for the fortification and stabilization of extra virgin olive oil using hydroxytyrosyl palmitate

Pure concentrates of eicosapentaenoic (EPA) and docosahexaenoic (DHA) acids were used to produce monoacylglycerol and diacylglycerol (MDG) oils via enzymatic glycerolysis in a solvent-free system. Immobilized lipase from Candida antarctica B (Novozym 435) was employed for the glycerolysis reaction with up to 90% product formation in one hour. This lipase also favoured diacylglycerol (DAG) over monoacylglycerol (MAG) production. Products were purified using silica gel chromatography and characterised by capillary chromatography with flame ionization detection (Iatroscan-FID). Purified products were added to extra virgin olive oil (EVOO) at a concentration of 20% w/w. The fortified olive oil was stabilized using hydroxytyrosyl palmitate, an antioxidant prepared by conjugating hydroxytyrosol with palmitic acid using Novozym 435 lipase. In vitro hydrolysis of the fortified oil was also carried out using porcine pancreatic lipase to investigate the mechanism of action of this enzyme on the oil mixtures.