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Despite considerable research efforts, lipase catalysis in a fluid milk system with aqueous multi-component mixtures containing multiple microphases, remains challenging. Pickering interfacial biocatalysis (PIB) platforms are typically fabricated with organic solvents/lipids and water. Whether a PIB with excellent catalytic performance can be constructed in complex milk mixtures remains unknown. Here, we challenged PIB with skim milk, and a small amount of flaxseed oil, and phytosterols as a model system for transesterification and lipolysis to enhance quality and flavor. The amino-modified mesoporous silica spheres (MSS-N) were employed as an emulsifier and carrier of lipase AYS (AYS@MSS-N). The conversion of phytosterol esters reached 75.5% at 1.5 h and prepared phytosterol ester-fortified milk with a content of 1.0 g/100 mL. The relative conversion rate remained above 70% after 6 cycles. In addition, the fortified milk showed an intensified and favorable effect on sensory traits through volatile flavor composition analysis. The findings provide a versatile alternative for PIB applications in complex environments, i.e., milk, which might inspire a new bioprocess strategy for dairy products.

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Phytosterol esters (PEs) and diacylglycerols (DAGs) have various health benefits in humans. In this study, PEs and DAGs were synthesized by lipase-catalyzed transesterification between a natural oil and phytosterols. First, commercial lipases were screened for transesterification and were further verified using multiple-ligand molecular docking. AYS "Amano" (a lipase from Candida rugosa) was found to be the optimum lipase. Subsequently, the enzymatic transesterification conditions were optimized. The optimized conditions were determined to be a 1:2 M ratio of phytosterols to oil, 100 mmol/L phytosterols, and 9 % AYS "Amano", and 50 °C for 24 h in 20 mL n-hexane. Under these conditions, over 70 % of phytosterols were converted to PEs. In this study, an efficient enzymatic process was developed to produce value-added functional oils rich in PEs and DAGs, with PEs content ≥ 31.6 %, DAGs content ≥ 11.2 %, acid value ≤ 0.91 mg KOH/g, and peroxide value ≤ 2.38 mmol/kg.

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Medium- and long-chain triacylglycerol (MLCT), as a novel functional lipid, is valuable due to its special nutritional properties. Its low content in natural resources and inefficient synthesis during preparation have limited its practical applications. In this study, we developed an effective Pickering emulsion interfacial catalysis system (PE system) for the enzymatic synthesis of MLCT by trans-esterification. Lipase NS 40086 served simultaneously as a catalyst and a solid emulsifier to stabilize the Pickering emulsion. Benefitting from the sufficient oil-water interface, the obtained PE system exhibited outstanding catalytic efficiency, achieving 77.5% of MLCT content within 30 min, 26% higher than that of a water-free system. The Km value (0.259 mM) and activation energy (14.45 kJ mol-1) were 6.8-fold and 1.6-fold lower than those of the water-free system, respectively. The kinetic parameters as well as the molecular dynamics simulation and the tunnel analysis implied that the oil-water interface enhanced the binding between substrate and lipase and thus boosted catalytic efficiency. The conformational changes in the lipase were further explored by FT-IR. This method could give a novel strategy for enhancing lipase activity and the design of efficient catalytic systems to produce added-value lipids. This work will open a new methodology for the enzymatic synthesis of structured lipids.

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A novel, fast, and cost-effective indirect enzymatic method was successfully developed to assess the total 3-monochloropropane-1,2-diol (3-MCPD) in canned food's oil fraction by the action of Burkholderia cepacia lipase. The total 3-MCPD were derivatized with n-Heptafluorobutyrylimidazole (HFBI) for GC-MS analysis during dispersive liquid-liquid microextraction (DLLME). An asymmetrical 2213//8 screening design was used to study the influence of critical factors on the method's effectiveness. The analytical features of the proposed method were assessed following Food and Drug Administration (FDA) guidelines using extra virgin olive oil (EVOO) as a blank sample. Outstanding results were achieved in terms of linearity (r2 = 0.9995), sensitivity, precision (2.1 % to 10.4 % RSD), and accuracy (98.7 % ≤ recovery ≤ 101.9 %). Method efficacy was tested by comparing the results of 10 edible oils for total 3-MCPD with those reported in previous works. A total of 41 samples were analyzed. The lowest 3-MCPD content was found in samples of albacore canned in EVOO oil, while the highest amounts were found in albacore, mackerel, and Atlantic saury samples, all preserved in refined sunflower oil.

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The rise in oil prices, global warming, and the depletion of nonrenewable resources have led researchers to study sustainable alternatives to increasing energy demand. The autocatalysis from castor oil and castor lipases to produce biodiesel can be an excellent alternative to reduce the production costs and avoid the drawbacks of chemical transesterification. This study aimed to evaluate the catalytic activity of castor bean lipase extract (CBLE) on three vegetable oils hydrolysis, to obtain and enhance biodiesel yield by an autocatalysis from castor oil and CBLE. Furthermore, the enzymatic biodiesel physicochemical quality was analyzed. The enzymatic activity for olive oil was 76.12 U, 90.06 U for commercial castor oil, and 75.60 U in raw castor oil. The hydrolysis percentages were high at 25 °C, pH 4.5, for 4 h with 97.18% for olive oil, 98.86%, and 96.19% for commercial and raw castor oil, respectively. The CBLE catalyzed the transesterification reaction on castor oil to obtain 82.91% biodiesel yield under the selected conditions of 20% lipase loading, 1:6 oil/methanol molar ratio, and 10% buffer pH 4.5, 37 °C for 8 h. The castor biodiesel quality satisfied the ASTM-D6751 (USA) and EN-14214 (European Union) values, except for the density, viscosity, and moisture, as expected for this kind of biodiesel.

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This study firstly addressed real swine wastewater (RSW) treatment by an indigenous Chlorella vulgaris MBFJNU-1 in 5-m3 outdoor open raceway ponds and then direct enzymatic transesterification of the resulting lipids from the wet biomass for sustainable biodiesel production. Compared to the control group, C. vulgaris MBFJNU-1 at 3% CO2 achieved higher microalgal biomass (478.5 mg/L) and total fatty acids content (21.3%), higher CO2 bio-fixation (63.2 mg/L/d) and lipid (9.1 mg/L/d) productivities, and greater nutrients removals (total nitrogen, 82.1%; total phosphorus, 28.4%; chemical oxygen demand, 37.1%). The highest biodiesel conversion (93.3%) was attained by enzymatic transesterification of wet disrupted Chlorella biomass with 5% lipase TL and 5% phospholipase PLA. Moreover, the enzymatic transesterification gave around 83% biodiesel conversion in a 15-L stirred tank bioreactor. Furthermore, the integrated process was a cost-effective approach to treat RSW and mitigate CO2 for microalgal biodiesel production, based on the mass and energy balances analysis.

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High energy demand driven by decreasing fossil fuels, and global warming because of the burning of fossil fuels necessitates the utilization of renewable and clean energy. One of these renewable energy sources is biodiesel. The increasing trend of biodiesel over the last 20 years tends to result in increasing glycerol (Gly), which is produced during the biodiesel production in 10% ratio (w/w) as a by-product. Using Gly as raw material is an alternative way to produce bio-based new products such as glycerol carbonate (GlyC). GlyC is a value-added product of Gly/vegetable oil and this product can be used as a potential fuel additive in the future because of its high oxygen content. Furthermore, GlyC shows a high reactivity; therefore, it is a bio-based building block for complex chemicals. The present review gives information about the bio-catalytic synthesis of GlyC from Gly/vegetable oil and, dimethyl carbonate (DMC). In addition, the influencing parameters of this bio-catalytic GlyC synthesis are discussed and reviewed in this paper.

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(-)-Epigallocatechin-3-O-gallate(EGCG) was enzymatically modified to enhance the lipophilicity and the antioxidant property. The determination of optimal reaction conditions are as follows: Lipase DF "Amano" 15 and acetone were used as catalyst and solvent, respectively. Equal molar of EGCG and vinyl laurate (1:1); lipase addition of 6.0% (w/w of total substrates); reaction temperature of 50°C and reaction time of 96 h, which obtained the conversion rate of EGCG at 80.1%. The structure of EGCG lauroyl derivatives were 5″-O-lauroyl-EGCG, 3″,5″-2-O-lauroyl-EGCG, and 5',3″,5″-3-O-lauroyl-EGCG, identified by high-performance liquid chromatography-mass spectrometry (HPLC-MS) and nuclear magnetic resonance (NMR). Compared with the logP of precursor EGCG (0.69 ± 0.03), the logP of EGCG lauroyl derivatives was 1.37 ± 0.19, 2.27 ± 0.33, and 3.28 ± 0.37, increasing by 0.98, 2.28, and 3.75 times, respectively (p < 0.05), suggesting the grafted fatty acid chains make EGCG derivatives more lipophilic, and the lipid solubility gradually increased as the number of substituents increased. Furthermore, EGCG lauroyl derivatives had excellent lipid oxidation than that of EGCG. The POVs (peroxide values) of soybean oil with mono-, di-, tri-lauroyl EGCG were significantly reduced by 42%, 47%, and 57% than that of EGCG at 21 days, respectively, indicating the antioxidative inhibition of these derivatives decreased with the increase in substituents. This indicates that these derivatives have broad prospects of the antioxidant application while improving their solubility properties in lipophilic environments/high-fat food. Practical Application: The lipophilic esterification reaction of EGCG catalyzed by new catalytic lipase DF "Amano" 15 was carried out in a non-aqueous solvent.Various reaction factors on a higher conversion rate of EGCG lauroyl derivatives were evaluated. The lipophilicity and antioxidant properties of EGCG lauroyl derivatives were much excellent than that of parent EGCG.

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Vinyl stearate was added to enzymatic transesterification of (-)-Epigallocatechin-3-O-gallate (EGCG) to enhance its lipophilicity and antioxidant ability in a non-aqueous system. The lipase DF "Amano" 15 was used as the catalyst. The optimal reaction conditions were: acetonitrile as the solvent, the molar ratio of vinyl stearate: EGCG as 3:1, an enzyme amount of 4.0% (ratio of substrate mass), and a reaction temperature and time of 50 °C and 96 h, respectively, achieving 65.2% EGCG conversion. HPLC-MS and NMR were used to determine the structure of EGCG stearyl derivative (3″,5″-2-O-stearyl-EGCG). The lipophilicity of EGCG stearyl derivatives (3.49 ± 0.34) was higher (5.06 times) than that of the parent EGCG (0.69 ± 0.08). Furthermore, EGCG stearyl derivatives had excellent lipid oxidation compared with BHT, BHA, and parent EGCG. The POVs of soybean oil with EGCG stearyl derivatives (18.17 ± 0.92 mEq/kg) were significantly reduced (by 62.5%) at 21 d compared with those of EGCG (48.50 ± 1.23 mEq/kg). These results indicate that EGCG derivatives have broad antioxidant application prospects in lipophilic environments/high-fat food.

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The recombinant lipase ofOphiostoma piceae (OPEr) is characterized by its prominent sterol esterase activity. The protein was immobilized on magnetic nanoparticles, giving four enzyme variants that have been tested in solvent-free transesterification of methyl oleate and sitostanol. The yields of stanol esters reached 85%, and the catalysts can be reused. Stanol esters were also obtained in a two-step cascade reaction; a mixture of fatty acid methyl esters was enzymatically synthesized from cooking oil wastes and then used for stanol transesterification. An 85% conversion was achieved in 2 h from the second cycle onward, maintaining the activity over 5 cycles. The biocatalysts can be safely used since they don't release toxic compounds for HeLa and A549 cell lines. These procedures comply with the principles of green chemistry and contribute to the sustainable production of these nutraceuticals from secondary raw materials, like the lipid fraction from industrial or agricultural residues.

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This study aimed to investigate the highly selective production of monolaurin via enzymatic transesterification of methyl laurate and glycerol. It was determined that a binary solvent system (tert-butanol/iso-propanol, 20:80, wt./wt.) was suitable for the enzymatic production of monolaurin, especially in the continuous process. The highest mass fraction of monolaurin in the product mixture (80.8 wt.%) was achieved in a batch mode under the following conditions: a methyl laurate-to-glycerol molar ratio of 1:6, a substrate concentration (methyl laurate in the binary solvent) of 15 wt.%, an enzyme dosage of 6 wt.% of the amount of methyl laurate, and a reaction time of 1.5 h at 50°C. Compared with the results under the batch conditions, a slightly higher yield of monolaurin (82.5 ± 2.5 wt.%) was obtained in a continuous flow system at a flow rate of 0.1 mL/min, while the mass fraction of dilaurin in the product mixture was only 0.7 ± 0.6 wt.%. In addition, the yield of monolaurin remained almost unchanged during the 18 tested days of the continuous experiment.

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Biodiesel is one of the best alternative to depleting fossil fuels for transport sector. However, biodiesel production via lipase mediated transesterification has limitation of high costing microbial enzymes. In order to overcome this limitation, a process of sequential treatment of oil industry wastewater using isolated lipolytic bacterial strains and biodiesel production from non-edible plant oils was studied. In this study, efficient lipase producing bacteria were isolated and evaluated for production of biodiesel from mustard, soybean, jatropha and taramira oils utilizing methanol for the transesterification of oils and bioremediation. Selected strains were then identified, using 16s rRNA sequencing. Further, Bacillus subtilis strain Q1 KX712301 was optimized for biodiesel production from non-edible taramira oil via Plackett-Burman and central composite design. Highest volumetric yield of biodiesel obtained was 102% at optimized parameters. Finally, a sequential bioremediation of vegetable oil contaminated wastewater and then microbial production of biodiesel from non-edible taramira oil was carried out using efficient lipase producer B. subtilis strain Q1 at optimized conditions. During sequential process, complete chemical oxigen demand reduction of oil containing wastewater and theoretical volumetric yield of biodiesel was achieved. Gas chromatography/mass spectrometry chromatogram revealed that the total fatty acid methyl ester content of the produced biodiesel was >98% which is in accordance with the biodiesel quality standards specified by both ASTM and EU-14103.

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Novel benzoxazole derivatives were synthesized, and their antitubercular activity against sensitive and drug-resistant Mycobacterium tuberculosis strains (M. tuberculosis H37 Rv, M. tuberculosis sp. 210, M. tuberculosis sp. 192, Mycobacterium scrofulaceum, Mycobacterium intracellulare, Mycobacterium fortuitum, Mycobacterium avium, and Mycobacterium kansasii) was evaluated. The chemical step included preparation of ketones, alcohols, and esters bearing benzoxazole moiety. All racemic mixtures of alcohols and esters were separated in Novozyme SP 435-catalyzed transesterification and hydrolysis, respectively. The transesterification reactions were carried out in various organic solvents (tert-butyl methyl ether, toluene, diethyl ether, and diisopropyl ether), and depending on the solvent, the enantioselectivity of the reactions ranged from 4 to >100. The enzymatic hydrolysis of esters was performed in 2 phase tert-butyl methyl ether/phosphate buffer (pH = 7.2) system and provided also enantiomerically enriched products (ee 88-99%). The antitubercular activity assay has shown that synthesized compounds exhibit an interesting antitubercular activity. Racemic mixtures of alcohols, (±)-4-(1,3-benzoxazol-2-ylsulfanyl)butan-2-ol ((±)-3a), (±)-4-[(5-bromo-1,3-benzoxazol-2-yl)sulfanyl]butan-2-ol ((±)-3b), and (±)-4-[(5,7-dibromo-1,3-benzoxazol-2-yl)sulfanyl]butan-2-ol ((±)-3c), displayed as high activity against M. scrofulaceum, M. intracellulare, M. fortuitum, and M. kansasii as commercially available antituberculosis drug-Isoniazid. Moreover, these compounds exhibited twice higher activity toward M. avium (MIC 12.5) compared with Isoniazid (MIC 50).

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Fish oil products in the form of triacylglycerols generally have relatively low contents of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) and so it is of potential research and industrial interest to enrich the related contents in commercial products. Thereby an economical and efficient two-stage preparation of EPA and DHA enriched fish oil triacylglycerols is proposed in this study. The first stage was the partial hydrolysis of fish oil by only 0.2 wt.‰ AY "Amano" 400SD which led to increases of EPA and DHA contents in acylglycerols from 19.30 and 13.09 wt % to 25.95 and 22.06 wt %, respectively. Subsequently, products of the first stage were subjected to transesterification with EPA and DHA enriched fatty acid ethyl esters (EDEE) as the second stage to afford EPA and DHA enriched fish oil triacylglycerols by using as low as 2 wt % Novozyme 435. EDEEs prepared from fish oil ethyl ester, and recycled DHA and EPA, respectively, were applied in this stage. Final products prepared with two different sources of EDEEs were composed of 97.62 and 95.92 wt % of triacylglycerols, respectively, with EPA and DHA contents of 28.20 and 21.41 wt % for the former and 25.61 and 17.40 wt % for the latter. Results not only demonstrate this two-stage process's capability and industrial value for enriching EPA and DHA in fish oil products, but also offer new opportunities for the development of fortified fish oil products.

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As the (R)-enantiomer of racemic atenolol has no ß-blocking activity and no lack of side effects, switching from the racemate to the (S)-atenolol is more favorable. Transesterification of racemic atenolol using free enzymes investigated as a resource to resolve the racemate via this method is limited. Screenings of enzyme, medium, and acetyl donor were conducted first to give Pseudomonas fluorescens lipase, tetrahydrofuran, and vinyl acetate. A statistical design of the experiment was then developed using Central Composite Design on some operational factors, which resulted in the conversions of 11.70-61.91% and substrate enantiomeric excess (ee) of 7.31-100%. The quadratic models are acceptable with R2 of 95.13% (conversion) and 89.63% (ee). The predicted values match the observed values reasonably well. Temperature, agitation speed, and substrate molar ratio factor have low effects on conversion and ee, but enzyme loading affects the responses highly. The interaction of temperature-agitation speed and temperature-substrate molar ratio show significant effects on conversion, while temperature-agitation speed, temperature-substrate molar ratio, and agitation speed-substrate molar ratio affect ee highly. Optimum conditions for the use of Pseudomonas fluorescens lipase, tetrahydrofuran, and vinyl acetate were found at 45°C, 175 rpm, 2000 U, and 1:3.6 substrate molar ratio.

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A series of new N-substituted benzimidazole derivatives was synthesized and their antifungal activity against Candida albicans was evaluated. The chemical step included synthesis of appropriate ketones containing benzimidazole ring, reduction of ketones to the racemic alcohols, and acetylation of alcohols to the esters. All benzimidazole derivatives were obtained with satisfactory yields and in relatively short times. All synthesized compounds exhibit significant antifungal activity against Candida albicans 900028 ATCC (% cell inhibition at 0.25 µg concentration > 98%). Additionally, racemic mixtures of alcohols were separated by lipase-catalyzed kinetic resolution. In the enzymatic step a transesterification reaction was applied and the influence of a lipase type and solvent on the enantioselectivity of the reaction was studied. The most selective enzymes were Novozyme SP 435 and lipase Amano AK from Pseudomonas fluorescens (E > 100).

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Feruloylated acylglycerols (FAGs) are the lipophilic derivatives of ferulic acid. In this work, soybean oil (SBO) and the mixed fatty acids (MFA) were selected as fatty acyl donors, and reacted with glyceryl monoferulate (GMF) to prepare FAGs in ionic liquids (ILs). Effect of various reaction parameters (time, temperature, enzyme concentration, and substrate ratio) and ILs on the GMF conversion and the reaction selectivity for FAGs formation were investigated. Response surface methodology (RSM) based on a 3-level-4-factor Box-Behnken experimental design was employed to evaluate the inactive effect of reaction parameters. For the esterification of GMF with MFA, the maximum GMF conversion (98.9 ± 0.9%) and FAG yield (88.9 ± 0.6%) were achieved in [C10mim]PF6. However, for the transesterification of GMF with SBO, the maximum GMF conversion (94.3 ± 0.7%) and FAG yield (83.8 ± 1.0%) were obtained in [C12mim]PF6. High FAG selectivities (∼0.90) were also obtained using SBO or MFA as acyl donors.

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An experimental study on enzymatic transesterification was performed to produce biodiesel from waste vegetable oils. Lipase from Pseudomonas cepacia was covalently immobilized on a epoxy-acrylic resin support. The immobilized enzyme exhibited high catalytic specific surface and allowed an easy recovery, regeneration and reutilisation of biocatalyst. Waste vegetable oils - such as frying oils, considered not competitive with food applications and wastes to be treated - were used as a source of glycerides. Ethanol was used as a short chain alcohol and was added in three steps with the aim to reduce its inhibitory effect on lipase activity. The effect of biocatalyst/substrate feed mass ratios and the waste oil quality have been investigated in order to estimate the process performances. Biocatalyst recovery and reuse have been also studied with the aim to verify the stability of the biocatalyst for its application in industrial scale.

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Conditions applied during frying require antioxidant which is stable at these conditions and provides protection for frying oil and fried food. Novel structured lipids containing nutraceuticals and antioxidants were formed by enzymatic transesterification, exploring canola oil and naturally occurring antioxidants such as ascorbic and selected phenolic acids as substrates. Lipozyme RM IM lipase from Rhizomucor miehei was used as biocatalyst. Frying performance and oxidative stability of the final transesterification products were evaluated. The novel lipids showed significantly improved frying performance compared to canola oil. Oxidative stability assessment of the structured lipids showed significant improvement in resistance to oxidative deterioration compared to original canola oil. Interestingly, the presence of ascorbic acid in an acylglycerol structure protected α-tocopherol against thermal degradation, which was not observed for the phenolic acids. Developed structured lipids containing nutraceuticals and antioxidants may directly affect nutritional properties of lipids also offering nutraceutical ingredients for food formulation.

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A novel enzymatic route of feruloylated structured lipids synthesis by the transesterification of ethyl ferulate (EF) with castor oil, in solvent-free system, was investigated. The transesterification reactions were catalysed by Novozym 435, Lipozyme RMIM, and Lipozyme TLIM, among which Novozym 435 showed the best catalysis performance. Effects of feruloyl donors, reaction variables, and ethanol removal on the transesterification were also studied. High EF conversion (∼100%) was obtained under the following conditions: enzyme load 20% (w/w, relative to the weight of substrates), reaction temperature 90 °C, substrate molar ratio 1:1 (EF/castor oil), 72 h, vacuum pressure 10 mmHg, and 200 rpm. Under these conditions, the transesterification product consisted of 62.6% lipophilic feruloylated structured lipids and 37.3% hydrophilic feruloylated lipids.

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