- Biocatalytic esterification in supercritical carbon dioxide by using a lipid-coated lipase
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A lipid-coated lipase is soluble and acts as a more efficient catalyst for triglyceride syntheses in supercritical carbon dioxide (scCO2) than in conventional organic solvents, and the reactivity can be controlled reversibly by changing pressure and temperature in scCO2.
- Mori, Toshiaki,Kobayashi, Atsushi,Okahata, Yoshio
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- Preparation of a Lipid-Coated Lipase and Catalysis of Glyceride Ester Syntheses in Homogeneous Organic Solvents
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A lipid-coated lipase was prepared by mixing aqueous solutions of lipase and dialkyl amphiphiles: A hydrophilic surface of the enzyme is converted with a lipid layer, of which lipophilic two-long-alkyl tails solubilize the enzyme in hydrophobic organic solvents.The lipid-coated lipase was prepared in various conditions by changing hydrophilic head groups of lipid molecules, a ratio of lipid/lipase, and an origin of lipase; the complex prepared from nonionic amphiphiles and lipase D from Rhizopus delemar showed a high stability and a high enzymatic activity in hydrophobic organic solutions.The lipid-coated lipase catalyzed di- and triacylglycerol syntheses from monoacylglycerols and aliphatic acids in the homogeneous and dry benzene solution in the presence of two pieces of molecular sieves (water: 80 ppm). the lipid-coated lipase could also catalyze ester exchange reactions in organic solvents with a small amount of water (250 ppm).Enzymatic activity was effected by a nature of organic solvents and a water content in organic solvents.The catalytic activity of the lipid-coated lipase was highly efficient compared with other enzyme systems such as the poly(ethylene glycol)-grafted lipase and the direct dispersion of lipase powder for glyceride syntheses in the dry organic solution.
- Okahata, Yoshio,Ijiro, Kuniharu
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- 4-O-Acetyl-3-O-tert-butyldimethylsilyl-l-rhamnal: a building block in the stereoselective synthesis of 2-deoxy-α-l-rhamnopyranosides
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The stereoselective synthesis of 2-deoxy-α-l-glycosides by addition of various acceptors to 4-O-acetyl-3-O-tert-butyldimethylsilyl-l-rhamnal promoted by triphenylphosphine-hydrogen bromide is developed.
- Wandzik, Ilona,Bieg, Tadeusz
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- Selective synthesis of glyceryl monolaurate intensified by boric acid based deep eutectic solvent
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Glyceryl monolaurate (GML), as one of widely used industrial chemicals, can be synthesized via Fischer esterification of lauric acid (LA) and glycerol (GL). In this work, we screened boric acid-based deep eutectic solvent (DES) formed from tetrapropylammonium bromide (TPAB) and boric acid to intensify the selective Fischer esterification through conductor-like screening model for realistic solvents (COSMO-RS) theory. The solid liquid equilibrium (SLE) phase behavior, hydrogen bond formation process, and thermal stability of the DES were characterized by differential scanning calorimetry (DSC), Fourier transform infrared spectrometry (FT-IR), and thermogravimetric analyzer (TGA). The results verified that equimolar TPAB and boric acid formed DES [TPAB:B(OH)3] with the lowest freezing point and very good thermal stability could efficiently intensify the Fischer esterification of GL and LA to GML. The hydrogen bond accepter TPAB of the DES made the esterification system homogeneous, which promoted the selective esterification process. In addition, the hydrogen bond donor B(OH)3 of the [TPAB:B(OH)3] combined with diol unit of GL to cyclic boric esters and led to a special selective space effect, which also improved the selectivity to GML. Thus, the esterification intensified of GL and LA by 20 wt% DES achieved GML selectivity of 85.7 % and yield of 76.4 % under the optimal reaction conditions. The esterification kinetics suggested the reaction followed pseudo-second-order model and the reaction activation energy was 33.98 kJ mol?1, similar to and/or lower than those reported works. Furthermore, DES and unreacted glycerol were readily recovered and reused through temperature controlled gravity-based separation due to the ability of homogeneity under reaction conditions and splitting phase behavior during the DES recovery. The results can expand the boric acid-based DESs for other potential intensification applications.
- Chen, Lifang,Cheng, Hongye,Qi, Zhiwen,Shen, Zilong
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- Enzymatic esterification of lauric acid to give monolaurin in a microreactor
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Monolaurin is a naturally occurring compound widely utilized in food and cosmetics. In this paper, we present a new method for the synthesis of monolaurin by esterification between lauric acid and glycerol catalyzed by Novozym 435 using a microreactor. The conversion of lauric acid is 87.04% in 20 min, compared with 70.54% via the batch approach in 5 h. Using an optimized solvent system consisting of t-BuOH/tert-amyl alcohol (1:1, v/v), the selectivity using the microreactor method is enhanced to 90.63% and the space–time yield of the process is 380.91 g/h/L. This newly devised method has the potential for application to other multiphase and enzymatic reactions.
- Li, Xin,Miao, Shanshan
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p. 660 - 667
(2021/03/03)
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- Ionic Liquid–Silicotungstic Acid Composites as Efficient and Recyclable Catalysts for the Selective Esterification of Glycerol with Lauric Acid to Monolaurin
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The synthesis of glycerol monolaurate (GML) by the esterification of glycerol (GL) with lauric acid (LA) over a series of propyl sulfonic acid-functionalized ionic liquids (SAFILs)-modified silicotungstic acid (STA; H4SiW12O40) composite catalysts has been investigated. The synthesized organic–inorganic hybrid catalysts were characterized by different physicochemical techniques. In particular, their acidic properties were studied by solid-state 31P magic angle spinning (MAS) NMR spectroscopy by using adsorbed trimethylphosphine oxide (TMPO) as a probe. The effects of key reaction parameters, such as glycerol/lauric acid molar ratio, amount of catalyst, reaction time, and reaction temperature on LA conversion and GML product yield were elucidated and optimized with response surface methodology (RSM). The N,N-dimethyl(benzyl)ammonium propyl sulfobetaine (DMBPS)-modified STA [DMBPSH]H3SiW12O40 exhibited the optimal catalytic activity and was exploited for process optimization. A highest GML yield of 79.1 % was achieved with the optimized reaction conditions. The high catalytic activity of these hybrid catalysts were attributed to strong acidity, low transport resistance, and their “pseudoliquid” characteristics. A kinetic study was made based on a second-order irreversible model of the esterification reaction, which resulted in an activation energy of 39.49 kJ mol?1 for [DMBPSH]H3SiW12O40 under optimized reaction conditions.
- Han, Xiaoxiang,Zhang, Xiaofang,Zhu, Guangqi,Liang, Juanjuan,Cao, Xianghui,Kan, Renjun,Hung, Chin-Te,Liu, Li-Li,Liu, Shang-Bin
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p. 2727 - 2738
(2017/07/28)
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- 1,2-Diacrylglycerol and wherein the intermediate preparation method
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The invention discloses a preparation method for diacylglycero and an intermediate thereof. The preparation method for diacylglycero comprises the following steps: in an ether solvent and/or an alcohol solvent, in the present of an alkali, performing hydrolysis reaction on a compound shown as a formula 5, so as to obtain diacylglycero which is 1 shown in a formula 1. R in the formula 5 and 5 is C14-C18 saturated or unsaturated aliphatic acyl. The preparation method is cheap in raw materials, mild in reaction conditions, safe in operation, simple in postprocessing operation, high in reaction conversion rate, high in yield and suitable for large-scale production.
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Paragraph 0138-0139
(2017/01/23)
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- Highly efficient solvent-free synthesis of 1,3-diacylglycerols by lipase immobilised on nano-sized magnetite particles
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Recently, 1,3-DAGs (1,3-diacylglycerols) have attracted considerable attention as healthy components of food, oil and pharmaceutical intermediates. Generally, 1,3-DAG is prepared by lipase-mediated catalysis in a solvent free system. However, the system's high reaction temperature (required to reach the reactants' melting point), high substrate concentration and high viscosity severely reduce the lipase's activity, selectivity and recycling efficiency. In this report, MjL (Mucor javanicus lipase) was found to have the best performance in the solvent-free synthesis of 1,3-DAGs of several common commercial lipases. By covalent binding to amino-group-activated NSM (nano-sized magnetite) particles and cross-linking to form an enzyme aggregate coat, MjL's specific activity increased 10-fold, and was able to be reused for 10 cycles with 90% residual activity at 55 °C. 1,3-DAGs of lauric, myristic, palmitic, stearic, oleic and linoleic acid were prepared using the resulting immobilised enzyme, all with yields greater than 90%, and the reaction time was also greatly reduced.
- Meng, Xiao,Xu, Gang,Zhou, Qin-Li,Wu, Jian-Ping,Yang, Li-Rong
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p. 319 - 324
(2013/10/08)
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- 1-O-Alkyl (di)glycerol ethers synthesis from methyl esters and triglycerides by two pathways: Catalytic reductive alkylation and transesterification/reduction
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From available and bio-sourced methyl esters, monoglycerides or oleic sunflower refined oil, the corresponding 1-O-alkyl (di)glycerol ethers were obtained in both high yields and selectivity by two different pathways. With methyl esters, a reductive alkylation with (di)glycerol was realized under 50 bar hydrogen pressure in the presence of 1 mol% of Pd/C and an acid co-catalyst. A second two step procedure was evaluated from methyl esters or triolein and consisted of a first transesterification to the corresponding monoglyceride with a BaO/Al2O3 catalyst, then its reduction to the desired glycerol monoether with a recyclable heterogeneous catalytic system Pd/C and Amberlyst 35 under H2 pressure. In addition, a mechanism for the reaction was also proposed.
- Sutter, Marc,Dayoub, Wissam,Metay, Estelle,Raoul, Yann,Lemaire, Marc
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supporting information
p. 786 - 797
(2013/04/24)
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- High purity palm monoglycerides
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The present invention relates to a process for producing high purity monoglycerides from edible oils/fats and fatty acids through glycerolysis, in particular but not exclusively to the production of monoglycerides from palm oil and palm oil products. This is achieved by providing a process for the production of monoglycerides of fatty acids or fats and oils, comprising the steps of reacting fatty acids or fats and oils with excess glycerol in the presence of an acidic or alkaline catalyst; substantially separating the crude reaction product from the other reaction components; removing unwanted reaction components from the crude reaction product by washing; drying the reaction product.
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Page/Page column 5
(2008/06/13)
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- HYDROLASES, NUCLEIC ACIDS ENCODING THEM AND MEHODS FOR MAKING AND USING THEM
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The invention provides hydrolases, polynucleotides encoding them, and methods of making and using these polynucleotides and polypeptides. In one aspect, the invention is directed to polypeptides, e.g., enzymes, having a hydrolase activity, e.g., an esterase, acylase, lipase, phospholipase (e.g., phosphlipase A, B, C and D acitvity, patatin activity, lipid acyl hydrolase (LAH) activity) or protease activity, including thermostable and thermotolerant hydrolase activity, and polynucleotides encoding these enzyme, and making and using these polynucleotides and polypeptides. The hydrolase activities of the polypeptides and peptides of the invention include esterase activity, lipase activity (hydrolysis of lipids), acidolysis reactions (to replace an esterified fatty acid with a free fatty acid), transesterification reactions (exchange of fatty acids between triglycerides), ester synthesis, ester interchange reactions, phospholipase activity and protease activity (hydrolysis of peptide bonds). The polypeptides of the invention can be used in a variety of pharmaceutical, agricultural and industrial contexts, including the manufacture of cosmetics and nutraceuticals. In another aspect, the polypeptides of the invention are used to synthesize enantiomerically pure chiral products.
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Page/Page column 227-228; 21/138
(2008/06/13)
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- Design of well balanced hydrophilic-lipophilic catalytic surfaces for the direct and selective monoesterification of various polyols
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The transesterification process is a well known reaction of organic chemistry. However, the monoesterification of unprotected polyols such as glycerol or sucrose is much more complex and the design of selective catalysts is becoming a huge challenge in order to avoid many protection and deprotection steps, harmful for the cost and the environmental impact of the resulting process. In this study, we showed that the control of the hydrophilic-lipophilic balance of heterogeneous catalysts is a crucial key in order to tune both the catalyst activity and the monoester selectivity. Indeed, whereas homogeneous guanidine led to low selectivity toward monoesters, its anchorage on a hydrophilic solid support such as silica allowed us to prepare two basic hybrid organic-inorganic materials able to selectively afford monoesters in high yield and in an environmentally-friendly process, at low temperature and starting from an equimolecular mixture of unprotected polyols and various fatty methyl esters. The Royal Society of Chemistry and the Centre National de la Recherche Scientifique 2005.
- Kharchafi, Ghizlane,Jerome, Francois,Adam, Isabelle,Pouilloux, Yannick,Barrault, Joel
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p. 928 - 934
(2007/10/03)
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- Lipase-catalyzed alcoholysis of triglycerides for short-chain monoglyceride production
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Lipase from Pseudomonas fluorescens efficiently catalyzed the alcoholysis of various TG in dry alcohols. For TG with short-chain FA, more MG were accumulated. The yields of MG were affected by the alcohols used. The maximum yields of MG were as follows: 8
- Lee, Guan-Chiun,Wang, Dong-Lin,Ho, Yi-Fang,Shaw, Jei-Fu
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p. 533 - 536
(2007/10/03)
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- Acid-catalyzed intra- and intermolecular acyl exchange in mono- and diglycerides
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Acid-catalyzed transformation of 1-monolauroylglycerine (1-MLG) was investigated. It has been demonstrated that 1-MLG disproportionates readily and quickly into a mixture of 1,2- and 1,3-diacylglycerines and glycerine. The transformation of 1,3-diglycerides into 1,2-diglycerides was studied.
- Isai,Usol'tsev,Stiba
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p. 325 - 329
(2007/10/03)
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- Development of an environmentally benign process for the production of fatty acid methyl esters
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The production of fatty acid methyl esters (FAME) is an important intermediate step in oleochemistry. The oleochemical production route starts with the renewable raw materials fat and oil and ends at fatty alcohols and different special products. Fatty acid methyl esters can be formed at mild reaction temperatures by transesterification of natural triglycerides (fats and oils). This contribution will show the development of a continuous process which is considering the main principles of production integrated environmental protection. The main advantages of this process are low energy consumption and minimal waste production. The process alternatives are shown and a scope on future problems which have to be solved to reach a real additional improvement of the fatty acid methyl esters production is given.
- Jordan,Gutsche
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- Enzymatic synthesis of symmetrical 1,3-diacylglycerols by direct esterification of glycerol in solvent-free system
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1,3-Diacylglycerols were synthesized by direct esterification of glycerol with free fatty acids in a solvent-free system. Free fatty acids with relatively low melting points (45°C) such as unsaturated and medium-chain saturated fatty acids were used. With stoichiometric ratios of the reactants and water removal by evaporation at 3 mm Hg vacuum applied at 1 h and thereafter, the maximal 1,3-diacylglycerol content in the reaction mixture was: 84.6% for 1,3-dicaprylin, 84.4% for 1,3-dicaprin, 74.3% for 1,3-dilinolein, 71.7% for 1,3-dieicosapentaenoin, 67.4% for 1,3-dilaurin, and 61.1% for 1,3-diolein. Some of the system's parameters (temperature, water removal, and molar ratio of the reactants) were optimized for the production of 1,3-dicaprylin, and the maximal yield reached 98%. The product was used for the chemical synthesis of 1,3-dicapryloyl-2-eicosapentaenoylglycerol. The yield after purification was 42%, and the purity of the triacylglycerol was 98% (both 1,3-dicapryloyl-2-eicosapentaenoylglycerol and 1,2-dicapryloyl-3-eicosapentaenoylglycerol included) by gas chromatographic analysis, of which 90% was the desired structured triacylglycerol (1,3-dicapryloyl-2-eicosapentaenoylglycerol) as determined by silver ion high-performance liquid chromatographic analysis.
- Rosu, Roxana,Yasui, Mamoru,Iwasaki, Yugo,Yamane, Tsuneo
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p. 839 - 843
(2007/10/03)
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- Mesoporous sulfonic acids as selective heterogeneous catalysts for the synthesis of monoglycerides
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Glycerol was esterified with an equimolar amount of lauric acid to monolaurin using zeolites, sulfonic resins, and sulfonic mesoporous materials as catalysts. The latter were obtained by immobilization of 3-mercaptopropyl groups and oxidation with H2O2. In particular, fatty acid conversions, monoglyceride yields, and selectivities obtained with mesoporous (ordered, amorphous) sulfonic catalysts were compared with those of other heterogeneous or homogeneous catalysts.When using silica gel coated with propylsulfonic acids, high reaction rates are coupled to high monoglyceride yields, e.g., 53% mono yield for a 1:1 glycerol:lauric acid ratio. Minimizing the autocatalytic contribution of the fatty acid reactant is a critical issue. The influence of a number of reaction parameters is investigated. The mesoporous sulfonic catalysts are also employed in the esterification of propanediols and meso-erythritol, and for reactions with other fatty acids.
- Bossaert, Wim D.,De Vos, Dirk E.,Van Rhijn, Wim M.,Bullen, Joren,Grobet, Piet J.,Jacobs, Pierre A.
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p. 156 - 164
(2007/10/03)
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- Phospholipid derivatives
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Phospholipid derivatives resulting from coupling of ascorbic acid to a glycerol ester or ether via a phosphoric acid residue and having antioxidant activity and lipid peroxide inhibiting activity, which have the formula STR1 wherein R1 and R2 represent the same or different and each represents an alkyl or acyl group and neither formula represents any particular configuration nor conformation.
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- Topical corticosteroid formulations
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This present invention relates to a solution for topical or local application comprising at least one corticosteroid; from about 1% to 4% by weight of solubilization agents consisting essentially of a combination of at least one glyceryl ester of a fatty acid of 6 to 22 carbon atoms and a betaine surfactant, from about 10% to 50% by weight of composition of an alkanol cosolvent, and from about 20% to 50% water.
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- Coal tar gel composition
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Compositions effective for topically treating skin conditions, especially psoriasis and eczema which contains as an essential ingredient coal tar in a gel base.
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