328 results about "Ester hydrolysis" patented technology

Disclosed is a method for preparation of molecular sieve modified by SBA- 15 surface sulfuric acid group, which contains the step: with polymer of the polyethylene glycol- polyglycerol- polyethylene glycol as the template agent, 3-mercaptopropyl-trimethoxysilane condensing ethyl orthosilicate in a acid condition, and by the oxidization of hydroperoxide, the molecular sieve modified by propanesulfonic acid being synthesized. The method for preparation is simple, the operation is easy, and the reaction condition is mild; the acid containing and the structure of the molecular can be regulated and controlled by regulating the matching of materials and processing parameter, the acid quantity being among 0.48- 1.15mmolH+/ g, specific surface being among 445- 680m2/ g, and the pore diameter being among 5.47- 7.58nm.

The invention discloses a castor oil-based hydrophilic chain extender as well as a preparation method and application thereof. According to the castor oil-based hydrophilic chain extender, starting from castor oil, one of the renewable resources, a hydroxyl group is introduced by mercapto group-ene light click reaction to obtain an intermediate, and then a carboxyl group is generated through hydrolysis reaction of an ester group (or ricinoleic acid is generated through ester hydrolysis reaction of castor oil first, and then the hydroxyl group is introduced by mercapto group-ene light click reaction), the hydrophilic chain extender containing at least two hydroxyl groups and a carboxyl group is prepared, and the hydrophilic chain extender is applied to preparation of anionic aqueous polyurethane emulsion. According to the castor oil-based hydrophilic chain extender as well as the preparation method and the application thereof, the castor oil is applied to hydrophilic chain extender rawmaterials, has positive reference value for broadening application and increasing added value of natural fat products and also plays a positive role in reducing or replacing an environment problem caused by the use of petroleum non-renewable resources. The castor oil-based hydrophilic chain extender prepared by the invention is liquid at normal temperature, a contact area with other raw materialsduring a reaction is larger, the mixing is more uniform and the reaction speed is higher.

The present invention discloses a hydrolysis process of methyl acetate by using cation exchange resin as catalyst and its equipment. Said hydrolysis equipment is a cylindrical tower, its interior contains reactive rectification section and stripping section, the hydrolysis reaction is implemented in reactive rectification section, and the reactive rectification structure unit being in reaction zone organically combines the catalyst loading, liquid distributor, overflow pipe and vapour-liquid contact equipment together, its structure is compact and its equipment efficiency is high. Its hydrolysis process is as follows; making water and methyl acetate product hydrolysis in the reaction zone according to a certain proportion, and making non-reacted reactant pass through the condenser and condensed, then returning it back into reaction zone to further react. Its ester hydrolysis rate is 40%-99.8%.

The invention provides a core-shell structure magnetic micro-spherical alumina MeFe2O4-SiO2-Al2O3 and the preparation method. According to the positioning effect of the LDHs laminated metal element, the invention firstly prepares the Me-Fe2+-Fe3+-LDHs laminated precursor by introducing the Me2+, Fe2+ and Fe3+ into the hydrotalcite laminate, and the spinel ferrite MeFe2O4 is formed by high-temperature roasting; the Na2SiO3.9H2O or silicon ester hydrolysis is adopted to coat a SiO2 protection layer on the surface of the MeFe2O4, the organic alcohol aluminum hydrolysis method is adopted to coat the alumina layer for a plurality of times, and finally the magnetic micro-spherical alumina MeFe2O4-SiO2-Al2O3 is obtained. The method saves the forming process of the traditional preparation method, and adjusts the magnetic structure and pore structure of the samples by changing the thickness of the SiO2 protection layer and the adding quantity of the magnetic object MeFe2O4 for meeting the application requirement of the magnetic stable bed process.

The invention discloses a hydrogel self-assembled microstructure template-based multifunctional superhydrophobic coating. Silicate ester is added into a hydrogel monomer (precursor) solution, after hydrogel monomer gelation and silicate ester hydrolysis, a silica microstructure film is formed, the silica microstructure film is modified by a self-assembled monomolecular film having hydrophobicity so that a super-hydrophobic coating is formed, the hydrogel monomer comprises at least one of aniline or its derivatives, and pyrrole or its derivatives, the silicate ester comprises at least one of methyl silicate, ethyl silicate, propyl silicate, butyl silicate and tetrachlorosilicane, and the self-assembled monomolecular film comprises at least one of silanization reagents such as alkylchlorosilane, alkylsiloxane, fluoroalkylchlorosilane and fluoroalkylsiloxane.

The invention provides a method of preparing an immobilized lipase. The method utilizes a coupling immobilization technology, that is a method of combination of adsorpting, crosslinking and embedding, to immobilize the lipase. Application of the coupling technology overcomes disadvantages of easily fell lipase and poor recycling rate caused by an adsorption method; the coupling technology has advantages of high bonding capacity of a crosslinking method and a high enzyme activity recovery of an embedding method, enables the lipase combined with a carrier to firmly immobilize on the carrier, and improves a repetition cyclic utilization rate and an enzyme activity. The immobilized lipase prepared by the technology can be used for esterification, transesterification, and ester hydrolysis, so that a conversion rate can reach more 90 %, a reaction time is shortened, a repetition utilization rate reaches more than 100 times, and an enzyme activity is reduced by less than or equal to 5 %. Therefore, the immobilized lipase has an industrial application prospect.

A stable pharmaceutical composition comprising about 1 wt. % to about 80 wt. % of an ACE inhibitor or a pharmaceutical acceptable salt thereof, about 1 wt. % to about 70 wt. % of an alkali or alkaline earth metal carbonate, and about 1 wt. % to about 80 wt. % of hydroxypropyl cellulose, wherein the ACE inhibitor is selected from the group consisting of quinapril, enalapril, spirapril, ramipril, perindopril, indolapril, lisinopril, alacepril, trandolapril, benazapril, libenzapril, delapril, cilazapril and combinations thereof; wherein the formation of an internal cyclization product, and/or ester hydrolysis product, and/or oxidation product, has been reduced or eliminated, and the weight percents are based on the total weight of the pharmaceutical composition. The stabilized pharmaceutical compositions of the invention exhibit a number of advantages as follows: (i) the ACE inhibitor or a pharmaceutical acceptable salt thereof present in the compositions is preserved from degradation; (ii) the compositions exhibit extended shelf-life under normal storage conditions; (iii) the effect of moisture on the compositions is minimized; (iv) the compositions exhibit minimal, if any, discoloration over a significant period of time; and (v) the compositions exhibit minimal, if any, instability when employed in the presence of colorants.

The invention provides a specific fluorescence probe substrates of human carboxylesterase 2 (CES2) and application thereof. The specific probe substrate is a benzoateb compound of a C4 hydroxyl naphthalimide, and is applicable to determine the enzyme activity of CES2 in a biological system. The CES2 enzyme activity determination flow comprises: selecting a hydrolysis benzoyl-removal reaction of the benzoate compound of the C4 hydroxyl naphthalimide as a probe reaction, and quantitatively determining the generation amount of a hydrolysis metabolite of the compound in a unit time, so as to determine the enzyme activity of CES2 in all biological samples, cells, bodies and integral organs. The probe is applicable to quantitative assessment of CES2 enzyme activity in biological samples of different species and different individual sources, and quantitative determination on CES2 enzyme activity in different sources of animal tissue cell culture fluids and cell preparation substances, so that the probe is expected to help to realize assessment on medicine disposal capability of important drug metablic enzyme CES2. Additionally, the probe also is applicable as an inhibitor for rapidly screening CES2 in vitro by means of the probe reaction.

The invention belongs to the technical field of micro-fluidic chips, and particularly relates to a proteolysis micro-fluidic chip based on a silica gel oxidized graphene composite membrane and a fabrication method of the proteolysis micro-fluidic chip. The fabrication method comprises the steps that chemical oxidization and ultrasonic dispersion are conducted on graphite powder, and an oxidized graphene aqueous solution is obtained; the oxidized graphene aqueous solution is mixed with a silica solution prepared by hydrolyzing n-silicane ethyl ester, and injected into an organic glass micro-fluidic chip channel with the surface subjected to silica gelation treatment; a modification solution is removed after a certain time; a micro-fluidic chip modified with the silica gel oxidized graphene composite membrane is obtained after drying; then, a mixed solution of 1-(3-dimethyl aminopropyl)-3-ethyl carbodiimide hydrochloride and N-hydroxyl succinimide is injected into the channel to allow carboxyl of oxidized graphene on the surface of the channel to be activated; a protease solution such as trypsin is injected to allow protease to be fixed by a covalent bond; and the proteolysis micro-fluidic chip is obtained. A micro-fluidic chip proteolysis reactor has the advantages of short enzymolysis time, low sample consumption, cheap price and the like.

An enzymatic process for preparing aliphatic polycarbonates via terpolymerization or transesterification using a dialkyl carbonate, an aliphatic diester, and an aliphatic diol or triol reactant. A catalyst having an enzyme capable of catalyzing an ester hydrolysis reaction in an aqueous environment is subsequently added to the reaction mixture. Next, polymerization of the reaction proceeds for an allotted time at a temperature≦100° C. Finally, the copolymer is isolated from an the catalyst via filtration.

The present invention discloses technological process and apparatus for hydrolyzing methyl acetate as the side product of refined terephthalic acid production. The technological process includes the following steps: the mixing between methyl acetate through active catalyst protecting column and methyl acetate through eliminating organic impurity and the catalytic hydrolysis reaction in the reaction area filled into cationic exchange resin inside the catalytic rectification tower; refluxing the un-hydrolyzed reactant in controlled ratio to the reaction area; and pumping out the liquid hydrolysate. The corresponding hydrolysis apparatus is one cylindrical tower in the diameter greater than 0.5 m and height greater than 20-24 m, and its catalytic rectification section has one catalyst bed layer in 6 m over thickness and comprising intersected catalyst structure units. The present invention can realize industrial scale hydrolysis of methyl acetate in required hydrolysis rate within 50-80 wt%.

The invention relates to a method for preparing chemically crosslinked photonic crystal hydrogel with an adjustable color. The method comprises the following steps: (1) dissolving N-isopropylacrylamide, N-hydroxyethyl acrylamide, a cross-linking agent and an emulsifier into deionized water, stirring, warming and keeping warm under the condition at 20-25 DEG C in a nitrogen condition, and then adding an initiator to continue to react for 1-4 hours, and dialyzing, so as to obtain a colloidal crystal hydrogel solution; (2) concentrating the obtained colloidal crystal hydrogel solution, standing at room temperature, adjusting the pH by adopting an NaOH solution, adding a crosslinking agent, evenly mixing, centrifuging, and standing at room temperature after taking, so as to obtain the chemically crosslinked photonic crystal hydrogel. The method is simple in process and low in cost, and the prepared photonic crystal hydrogel has thermosensibility. In addition, the obtained photonic crystal hydrogel is good in stability, and free of hydrolysis, the problem that nano hydrogel is easily decomposed because of ester hydrolysis in 2-hydroxy ethyl acrylate is solved, and the defects of the photonic crystal hydrogel in application are compensated.

A heat-resistant cutinase and its coding gene and expression belong to the technical field of bioengineering. The present invention provides a bacterial cutinase different from fungal cutinase, its encoding gene and expression system, including extracting the total DNA of Thermobifida fusca WSH03-11, designing primers, and PCR amplification to obtain the gene encoding heat-resistant cutinase, It has the nucleotide sequence shown in SEQ ID NO: 1, the full length is 906 nucleotides, and it encodes 301 amino acids. The plasmid pET20b(+) is used as the expression vector, and E.coli BL21 Rosetta(DE3)PlysS is used as the expression vector. The host can realize the high-efficiency expression of the heat-resistant cutinase gene. This cutinase has good thermal stability and has a good hydrolysis effect on cutin, triglyceride and various soluble synthetic esters, and can be widely used in textile, detergent and other industries.

The invention belongs to the field of preparation and application of composite photocatalytic materials and particularly relates to an Au/TiO2/metal-organic framework composite photocatalyst and preparation and application of the Au/TiO2/metal-organic framework composite photocatalyst. The preparation comprises the steps: preparing monodisperse cation polystyrene microspheres from styrene and methylacryloyloxy trimethylammonium chloride, which serve as monomers, and then, forming cobalt metal-organic frameworks on surfaces of the polystyrene microspheres by a layer-by-layer assembling method in a manner of taking the polystyrene microspheres as a template, so as to prepare styrene-cobalt metal-organic framework core-shell structures; carrying out hydrolysis by tetrabutyl titanate in the presence of ammonia water, so as to prepare TiO2-loaded mono-styrene-cobalt metal-organic framework core-shell structures; further, carrying out ultraviolet irradiation to photocatalytically reduce Au<3+> into Au, so as to modify TiO2; and finally, removing polystyrene cores, thereby obtaining the Au/TiO2/metal-organic framework composite photocatalyst. The catalyst has the characteristics of low density, large specific surface area, no agglomeration, stable catalytic performance, high photocatalytic activity, and the like.

The invention relates to an ultrahigh-transparency large-size block silicon dioxide aerogel and a preparation method and application thereof. The method comprises the following steps: uniformly mixingtetramethyl orthosilicate, long-chain alkyl trimethoxy silane, an alcohol solvent, water and an alkali catalyst, carrying out hydrolysis reaction to obtain sol, and putting the sol into a mold to carry out sol-gel reaction to obtain wet gel; carrying out gradient heating aging on the wet gel to obtain skeleton-reinforced wet gel; and sequentially carrying out solvent replacement and supercriticaldrying on the skeleton-reinforced wet gel to obtain the ultrahigh-transparency large-size block silicon dioxide aerogel. According to the preparation method disclosed by the invention, superfine silicon dioxide sol generated by hydrolyzing long-chain alkyl trimethoxy silane stable tetramethyl orthosilicate is introduced, and the reaction activity of the sol is controllably adjusted so that the accurate regulation and control of a gelling process are realized; the aerogel prepared by the method has the characteristics of ultrahigh transparency, large size, super heat insulation capability, super hydrophobicity and the like, and has great economic value in the field of transparent heat insulation.

The invention discloses a process for preparing and purifying ultra low molecular weight heparin sodium (calcium), which comprises the following steps of: reacting heparin with organic quaternary ammonium salt to generate heparin quaternary ammonium salt, performing nucleophilic substitution to generate heparin benzyl ester, and degrading under the alkaline condition to obtain a low molecular weight heparin fragment; and separating and purifying by an inorganic ceramic ultrafiltration and hollow fiber ultrafiltration combined method to obtain the ultra low molecular weight heparin sodium (calcium) of which the molecular weight distribution is 2,000 to 2,500D and the average molecular weight is 2,200D. The low molecular weight heparin fragment is obtained by controlling reaction conditions in the esterification process and the degradation time of ester hydrolysis; a ceramic membrane and a hollow fiber ultrafiltration membrane are combined to separate and purify the heparin fragment; and by selecting the pore diameter of the ceramic membrane, operating pressure, feed liquid temperature, and the molecular weight cutoff of the hollow ceramic membrane, the heparin fragment with a reasonable molecular weight distribution range is effectively separated.

A process is disclosed for simultaneously extracting, saponifying, and isolating lutein without the use of harmful organic solvents. In one embodiment the method includes (a) dispersing Marigold oleoresin in an alkane hydrocarbon alkanol solution, (b) adding a potassium hydroxide to the Marigold oleoresin and alkane hydrocarbon alkanol solution to form a homogenous solution of Marigold oleoresin, (c) refluxing the homogeneous solution until ester hydrolysis of the Marigold oleoresin is completed, (d) cooling the homogeneous solution and allowing it to settle until lutein crystals are formed and (e) washing the lutein crystals with methanol-hexane solution to separate and filter them from the solvents.

The invention provides a method for preparing a dabigatran etexilate hydrolysis impurity A. The method comprises steps as follows: (1) dabigatran etexilate or dabigatran etexilate mesylate is used as a raw material and dissolved in a mixed medium of an organic solvent and an alkaline aqueous solution for a hydrolysis reaction; (2) a mixed liquid obtained in Step (1) is adjusted to be acidic, and grease is separated out; (3) the organic solvent is added to the grease, crystals are separated out, and the impurity A is obtained. The invention further provides a method for preparing a dabigatran etexilate hydrolysis impurity B. The method comprises steps as follows: (1) the dabigatran etexilate hydrolysis impurity A is used as a raw material and dissolved in a mixed medium of the organic solvent and an acidic aqueous solution for a hydrolysis reaction; (2) a mixed liquid obtained in Step (1) is depressurized and distilled until grease is produced, and extraction is performed with dichloromethane; (3) an obtained extraction liquid is purified with medium-pressure preparation chromatography, the solvent is removed, and the grease is obtained; (4) ethyl acetate is added, crystals are separated out after dissolution, and the impurity B is obtained.

The invention discloses a preparation process of an insulin sensitizer. The preparation process comprises the following steps: mixing 2-(4-fluorobenzoyl) cyclohexanone, L-tyrosine methyl ester, dioxane and methylbenzene, filling nitrogen and reacting, carrying out a distilling procedure, and reacting with the addition of anisole and palladium/carbon so as to obtain a first product; mixing the first product with dichloromethane, adding methylsufonyl chloride and pyridine, reacting, distilling and removing dichloromethane so as to obtain a second product; mixing for reacting the second product with tetrahydrofuran and 1,2-dibromoethane, and thinning with water so as to obtain a third product; and mixing for reacting the third product with salt, cuprous chloride, carbazole, 8-hydroxyquinoline and dimethyl sulfoxide, thinning with water and extracting with ethyl acetate, distilling and removing ethyl acetate so as to obtain a final product, namely 2-[2-(4-fluorobenzoyl) aniline]-3-[4-(2-carbazolyl ethyoxyl) phenyl] methyl propionate. The yield of the final product is 47%; and in the process of joining the final product and carbazole, the circumstance of ester hydrolysis in a synthesis reaction of the novel insulin sensitizer, namely chiglitazar, is avoided.

The invention provides a preparation method for a Cu2O/TiO2 composite photo-thermal catalyst. The preparation method comprises the following steps: preparation of a butyl titanate hydrolysis buffer solution; preparation of nanometer TiO2 catalyst powder; and preparation of the Cu2O/TiO2 composite photo-thermal catalyst with photo-thermal concerted catalysis effect. The invention has the following beneficial effects: the Cu2O/TiO2 composite photo-thermal catalyst has photo-thermal concerted catalysis effect, and the photo-thermal concerted catalysis effect is increased by 30 to 40% compared with single photocatalysis effect, by 50 to 60% compared with single thermocatalysis effect and by 20% compared with superposed photocatalysis effect and thermocatalysis effect; and from the perspective of energy utilization, the Cu2O/TiO2 composite photo-thermal catalyst can effectively use luminous energy and heat energy for catalytic reaction and has the advantages of energy conservation and high efficiency.

The invention relates to a preparation method of prednisolone. The preparation method comprises the steps of sequentially carrying out 3, 20-keto protective reaction, 11-keto reduction reaction, 21-hydroxyl esterification reaction, 3, 20-keto deprotection reaction and 21-acetic ester hydrolysis reaction by taking prednisone acetate as a raw material to obtain prednisolone. The invention provides a novel synthesis route sequentially comprising the steps of esterifying and deprotecting; nitrosification quenching reaction and resin hydrolysis reaction are omitted in the deprotection process; and ester hydrolysis reaction is finished under the protection of a mixed solvent and inert gases, so that the condition that byproducts are produced by hydrolysis reaction is avoided. The preparation method is novel in process route, simple and rapid in operation process, low in production cost and suitable for large-scale industrial production.

An enzymatic process for preparing aliphatic polycarbonates via terpolymerization or transesterification using a dialkyl carbonate, an aliphatic diester, and an aliphatic diol or triol reactant. A catalyst having an enzyme capable of catalyzing an ester hydrolysis reaction in an aqueous environment is subsequently added to the reaction mixture. Next, polymerization of the reaction proceeds for an allotted time at a temperature ≦100° C. Finally, the copolymer is isolated from an the catalyst via filtration.

The invention relates to a pichia pastoris gene engineering strain for producing lipase and a building method of the pichia pastoris gene engineering strain. During the enzymic catalytic reaction of the lipase, if the reaction promotes esterolysis in the oil-water interface, enzymatic synthesis and ester exchange can be achieved in the organic phase, and accordingly biodiesel can be synthesized by using waste edible oil, waste industrial oil and low-carbon alcohol as the raw materials. The lipase is massively fermented by transferring recombinant lipase Lip14 genes into pichia pastoris X33. P-nitrophenyl palmitate is used as the substrate to measure the long-chain lipid hydrolysis ability of the lipase, p-nitrophenyl laurate and p-nitrophenyl octoate are used to measure the medium-chain lipid hydrolysis ability of the lipase, p-nitrophenyl butyrate is used to measure the short-chain lipid hydrolysis ability of the lipase, and accordingly the long-chain, medium-chain and short-chain lipid hydrolysis activity of the lipase can be determined and a foundation is laid for the application of the lipase to the catalytic production of biodiesel.