- Selective synthesis of glyceryl monolaurate intensified by boric acid based deep eutectic solvent
-
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
-
-
Read Online
- Application of chemoenzymatic hydrolysis in the synthesis of 2-monoacylglycerols
-
The selective biocatalyzed synthesis of 2-monoacylglycerols (2-MAGs) through the use of commercially available immobilized Candida antarctica (Novozym435) and Rhizomucor miehei is explored. Reactions at room temperature result in the formation of a 2-MAG and a corresponding ethyl ester of the fatty acid with immobilized C. antarctica within 2 h with yields ranging from 36% to 83%. Similar reaction conditions with immobilized R. miehei yielded exclusively the 2-MAG after 24 h with yields ranging from 37% to 88%. Yields vary on the acyl group at the sn-2 position and choice of enzyme involved.
- Whitten, Kyle M.,Makriyannis, Alexandros,Vadivel, Subramanian K.
-
experimental part
p. 5422 - 5428
(2012/09/08)
-
- High purity palm monoglycerides
-
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.
- -
-
Page/Page column 5
(2008/06/13)
-
- Enzymatic preparation of enantiomerically pure sn-2,3-diacylglycerols: A stereoselective ethanolysis approach
-
Stereoselective ethanolysis of monoacid TAG by immobilized Rhizomucor miehei lipase (RML) was studied for preparation of optically pure sn-2,3-DAC. Trioctanoylglycerol (TO) was used as a model substrate. The enantiomeric purity of the product, sn-2,3-dioctanoylglycerol (sn-2,3-DO), was very high (percent enantiomeric excess > 99%) when an excess of ethanol was used. The result indicated that RML was highly stereosRMLelective toward the sn-1 position of TO under conditions of excess ethanol. The stereoselectivity of RML depended on the amount of ethanol. The larger the amount of ethanol was, the higher the stereoselectivity became. After optimizing the parameters such as reactant molar ratio, water content, and temperature, (ethanol/TO molar ratio = 31:1 and water content = 7.5 wt% of the reactants at 25°C), optically pure sn-2,3-DO was obtained at 61.1 mol% in the glyceride fraction in 20 min. The above conditions were further applied for ethanolysis of monoacid TAG with different acyl groups such as tridecanoylglycerol (C10:0), tridodecanoylglycerol (C12:0), tritetradecanoylglycerol (C14:0) and trioctadecenoylglycerol [triolein, (C18:1)]. The yields and enantiomeric purities of 1,2(2,3)-DAG were dramatically reduced when TAG with FA longer than decanoic acid were used. Copyright
- Piyatheerawong, Weera,Yamane, Tsuneo,Nakano, Hideo,Iwasaki, Yugo
-
p. 603 - 607
(2007/10/03)
-
- Design of well balanced hydrophilic-lipophilic catalytic surfaces for the direct and selective monoesterification of various polyols
-
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
-
p. 928 - 934
(2007/10/03)
-
- HYDROLASES, NUCLEIC ACIDS ENCODING THEM AND MEHODS FOR MAKING AND USING THEM
-
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.
- -
-
Page/Page column 227-228; 21/138
(2008/06/13)
-
- Acid-catalyzed intra- and intermolecular acyl exchange in mono- and diglycerides
-
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
-
p. 325 - 329
(2007/10/03)
-
- Mesoporous sulfonic acids as selective heterogeneous catalysts for the synthesis of monoglycerides
-
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.
-
p. 156 - 164
(2007/10/03)
-
- Kinetics of acyl migration in monoglycerides and dependence on acyl chainlength
-
The chemical rearrangement reaction of β- into α-monoglycerides is described. Four monoglycerides with different fatty acid chainlength have been investigated, and the equilibrium constant and the reaction velocity constants characterizing the reaction of the chemical rearrangement were estimated with a mathematical model. A 1:6.5 mixture of α/β-monoglycerides appeared to rearrange to a mixture of 1:1 α/β-monoglycerides within 24 h. Furthermore, the reaction velocity of the rearrangement reaction of β- to α-monoglycerides depended on the fatty acyl chainlength in the monoglyceride.
- Boswinkel,Derksen,Van't Riet,Cuperus
-
p. 707 - 711
(2007/10/03)
-
- Polyhydroxyl non-ionic surfactant, process for preparing the same and cosmetic composition containing the same
-
Polyhydroxyl non-ionic surface active agents, for use in a cosmetic composition such as hair dye or shampoo composition is prepared by condensing glycidol on a polyhydroxyl fatty chain reactant in the presence of an acid catalyst at a temperature of 50°-120° C.
- -
-
-