120 results about "Product inhibition" patented technology

The invention relates to biomass supercritical and subcritical combined continuous type pretreatment and hydrolysis equipment and a method. The equipment comprises a water storage tank, a material storage tank with a stirring device, a preheating system, a supercritical reaction system, a primary cooling system, a subcritical reaction system, a final cooling system, a product collection system and an electronic temperature controlling system. The method comprises the following processing steps: water reaching preheat temperature and biomass material paste are rapidly mixed and then injected into the supercritical reaction system to be pretreated under supercritical condition; the reaction product is cooled through the primary cooling system and depressurized through a pressure reducing valve and then enters into the subcritical reaction system to be hydrolyzed sequentially, therefore fermentable sugars are continuously generated and collected. The invention utilizes the advantages of the supercritical method that the reaction is rapid, activator is not required and product inhibition does not exit, realizes that the continuous hydrolysis conversion of wood fiber biomass can generate fermentable sugars, is the foundation of subsequent resource recovery technologies, such as ethanol production by fermentation and the like, and has wide application prospect.

The invention discloses a method for continuously producing biological butanol by fermentation, separation and coupling of a static bed. The method comprises the following steps of: filling a modified immobilized medium into the static bed, and circularly connecting in series with a bioreactor; incubating a butanol producing strain into the bioreactor, culturing the butanol producing strain in a fermentation medium, circulating fermentation liquor between the static bed and the bioreactor, and gradually absorbing free thallus cells into the static bed; pumping the fermentation liquor into a pervaporation membrane module for separation when the concentration of the butanol in the bioreactor is between 3 and 7g/L, collecting penetrating fluid, and returning liquid intercepted by a membrane to the bioreactor for continuous use; meanwhile, adding the fermentation medium into the midstream of the bioreactor, and continuously fermenting to produce the butanol. The method obviously weakens the pollution of the pervaporation membrane existing in the process of in situ separation and coupling, prolongs the operation time and service life of the membrane, eliminates butanol product inhibition in a fermentation process, and realizes the high-efficient and continuous production of the biological butanol.

The invention relates to a method for producing glutathione based on enzymic method in vitro. Through expression and catalysis of glutathione compound difunctional enzymes and polyphosphoric acid kinases, tetraphosphate and hexametaphosphate serve as phosphoric acid donors to regenerate ATP (adenosine triphosphate), and the glutathione is generated under the catalytic action of the glutathione compound difunctional enzymes by taking glutamic acid, glycine and cysteine as substrates. Compared with existing glutathione production methods, the method has the advantages that inhibition effect of the glutathione compound difunctional enzymes is low, and the content of the glutathione obtained from a reaction system is high; sodium and kali salt of phosphoric acid donors, such as the tetraphosphate and the hexametaphosphate, used in the reaction process is low in cost and easy to get; the phosphoric acid donors serve as substrates of the polyphosphoric acid to generate the ATP, and accordingly, production cost is reduced greatly; the amino acid ratio of Gly:Gys:Gly is lowered to 2:1:2, the content of amino acid in the system is low, and later product separation is facilitated.

The present invention belongs to the field of biological sterol transforming technology, and is especially biological sterol transforming process with cyclodextrin and its derivative and its preparation. In a transforming system, cyclodextrin or its derivative in certain amount is added, or substrate and cyclodextrin or its derivative in certain ratio are made to form inclusion compound, so as to facilitate transformation. The process of the present invention is especially suitable for microbial transformation of hydrophobic compound, and can raise the solubility of reaction substrate in water solution, raise the substrate utilizing rate and reaction rate, release substrate and product inhibition and raise product converting rate. When the substrate concentration is 3-20g/L, the present invention has conversion period shorted to 3-4 days, conversion rate of 50-95 % and high industrial application value.

A universal linker structure is provided, in which a functional group and activating leaving group are placed on a tether, allowing the placement of an electrophile at the end of any nucleic acid sequence. The electrophile on the tether can react with a second nucleic acid carrying a nucleophile when the two nucleic acids are hybridized near one another, resulting in release of the leaving group, and creation of a functional change. The linker can be designed to destabilize the ligation product without slowing the rate of reaction. This lowers product inhibition, and the target DNA or RNA can become a catalyst for isothermally generating multiple signals for detection. This enhanced signal is demonstrated in solution experiments and in solid supported assays. The universal linkers of the present invention are simple and inexpensive to prepare, and can be appended to any polynucleotide in automated steps on a standard DNA synthesizer.

The invention discloses a trichoderma viride W2 capable of producing a thermophilic ethanol-resistant beta-glucosidase and an application thereof. The trichoderma viride W2 is preserved in the China General Microbiological Culture Collection Center (CGMCC) on August 23, 2010, and the preservation number of the trichoderma viride W2 is CGMCC No.4098. The trichoderma viride W2 can produce a new beta-glucosidase, the enzymatic activity of the new beta-glucosidase reaches 346.7U/mL, the optimal reaction pH value is 4.8, the optimal reaction temperature is 70 DEG C, and the new beta-glucosidase is suitable for pyrohydrolysis and has an obvious glucose feedback inhibition effect. The ethanol the concentration of which is 10% has a maximal effect on promoting the enzymatic activity and improves the enzymatic activity of the beta-glucosidase by 1.6 times, and the resistant ability of the ethanol reaches 30%, so that the cellobiose inhibition can be effectively eliminated, the yield of the ethanol is improved by nearly 3 times, and the terminal product inhibition is effectively eliminated. Thus, the beta-glucosidase can be used for simultaneous saccharification and fermentation of lignocellulose raw materials, has a rare promoting effect in China, effectively increases the yield of the cellulosic ethanol, lowers the production cost, and accelerates the industrialized progress of the cellulosic ethanol.

The invention provides a recombinant escherichia coli for preparing (S)-4-chlorine-3-hydroxyl ethyl butyrate by adopting asymmetric transformation and an application of the recombinant escherichia coli. The recombinant escherichia coli simultaneously comprises a carbonyl reductase gene and a glucose dehydrogenase gene; the sequences of the carbonyl reductase gene and the glucose dehydrogenase gene are respectively shown in SEQ ID NO.1 and SEQ ID NO.3. The recombinant escherichia coli provided by the invention can be applied to high-activity and high-selectivity catalysis of COBE to generate (S)-CHBE; the enzyme activity can be up to 33.1U/mg, and reaches the highest level reported in the literature; substrate and product inhibition are removed in situ by virtue of macroreticular resin, so that the accumulation of the final product (S)-CHBE can reach 3,000mM; the transformation rate of the final substrate can be up to 100%; the optical purity e.e% of the product cam reach 99.4%; and compared with the prior art, the optical purity is significantly improved.

The invention provides a method for producing antimicrobial peptide through fermentation of brevibacillus laterosporu. In fermentation of the brevibacillus laterosporu, when the yield of the antimicrobial peptide is no longer increased, active carbon is directly added into the fermentation liquor; as the active carbon adsorbs the fermentation product, the inhibiting effect of the product is relieved, and the density of the thallus and the yield of the antimicrobial peptide are greatly improved. According to the method, the active carbon is taken as an adsorption stripping coupling agent, has low cost, is environmentally friendly, and can be directly added in the fermentation process without being activated in advance; the antimicrobial peptide can be adsorbed without regulating the pH value of the fermentation liquor; and the method is simple and easy to promote, and the active carbon can be regenerated through desorption after fermentation, thus being recycled repeatedly, and lowering the production cost.

The invention discloses a method and a device for the continuous fermentation and separate coupling of biomacromolecule products. By utilizing membrane in a fermentor and a membrane separation device outside the fermentor, while target biomacromolecules are fermented and produced, target products are continuously separated out from the fermentor through a membrane system so as to remove the product inhibition of fermentation and reduce the viscosity of fermentation broth. Continuous or semi-continuous fermentation and separate coupling are realized through one set or a plurality of sets of fed-batch devices so as to improve equipment utilization rate and raw-material conversion rate, reduce production cost and raise the continuous and automation level of a process. As fermentation and product extraction are hermetically carried out in a container and a pipeline, external pollution and interference are reduced. In addition, for certain extrazellular synthetic biomacromolecules, due to the separation control of the membrane on molecular weight, the molecular weight of macromolecules can be simultaneously controlled during fermentation so as to obtain products uniform in molecular weight.

The invention discloses a method for preparing gardenia blue by utilizing phase-transfer catalysis. The method comprises the following steps: peeling off gardenia jasminoides fruits, crushing into fruit powder, adding ethanol water for supersonic extraction, filtering, performing vacuum concentration on the filtrate, recycling ethanol, drying the solid obtained through concentration, and dissolving the solid into water so as to obtain a crude geniposide product solution; mixing the crude geniposide product solution with beta-glucosidase to be used as a water phase, performing catalytic hydrolysis reaction under the condition of oscillation or stirring so as to obtain an intermediate product genipin by using an organic solvent as an organic phase; adding a solution of hydrophilic amino acid into the organic phase, subsequently reacting under the condition of oscillation or stirring so as to prepare the gardenia blue; concentrating and drying the water phase in vacuum so as to obtain gardenia blue powder. According to the method, a reaction-extraction technique is utilized, product inhibition and side product degradation reaction when the genipin is prepared by using an ordinary method are effectively prevented, and the conversion rate of geniposide is high, and meanwhile high-purity gardenia blue can be obtained through reverse extraction by using an amino acid solution, and an organic solvent can be recycled.

The invention provides a mutant cephalosporin C acylase. One or a plurality of amino acid locus replacement is carried out on an amino acid sequence shown as SEQ ID NO.1 in a sequence table to obtain a mutant amino acid sequence; and one or more of 288-locus valine, 296-locus histidine and 417-locus histidine is or are adopted as amino acid locus(es). The technical problems that the mutant cephalosporin C acylase of the prior art has small catalytic activity, seriously influenced enzymatic activity by the outside and product inhibition are solved.

The present invention has the technology scheme of adopting microbial zymogene preparation containing neurospora and saccharomycete. The fermentation process with the microbial zymogene preparation of the present invention to produce feed or alcohol is to add the microbial zymogene preparation components simultaneously or gradually and to process the obtained material for producing feed or alcohol. The present invention has the beneficial effect that the coupled and synergistic fermentation with the microbial zymogene preparation can eliminate the feedback suppression and saccharide or ethanol product suppression in the fermentation, raise the protein content, soften material, generate spirit fragrance, improve the taste of feed and raise production efficiency and product quality.

The invention discloses preparation and an application of an L-amino acid deaminase mutant, and belongs to the technical field of gene engineering. According to a modification method disclosed by theinvention, through protein modification of pmirLAAD, by analyzing a flexible Loop ring structure around a binding site of a pmirLAAD product and designing an optimal mutant, a defect that catalytic efficiency of a previous wild type enzyme is reduced due to product inhibition is overcome, and experimental verification is performed. And the optimal mutant pmirLAADM4 is obtained, and the catalytic efficiency (1.61 mM<-1>. Min<-1>) and a product inhibition constant (5.4 mM) are improved by 5.2 times and 5.7 times respectively compared with those of a contrast group. A yield of alpha-ketoisovaleric acid can reach 96.5 g/L, and a conversion rate is greater than 97%. By using the method provided by the invention, cost can be greatly reduced, and an industrial process of producing the alpha-ketoisovaleric acid by an enzymatic conversion method is accelerated.

The invention discloses a product-resistant inhibitory mutated cephalosporin C acylase, a gene carrier and a transformant of the enzyme, and application of the enzyme in one-step enzymatic production of 7-aminocephalosporanic acid, belonging to the technical field of enzyme engineering and biotechnology industry. The amino acid sequence of the enzyme is obtained by conducting deletion mutation on the amino acid sequence of cephalosporin C acylase coded by the gene sequence SEQ ID NO:1 to obtain enzyme CPCAcy-D2 and CPCAcy-D4. The amino acid sequences are shown as SEQ ID NO:2 and SEQ ID NO:3, respectively. The invention also discloses the gene carrier, the transformant, and the application of the enzyme. The enzyme has high expressing activity, and also the tolerance of the product is improved significantly, so that CPC is catalyzed efficiently to produce 7-ACA.

Disclosed is a process for carrying out a cyclisation reaction, a polymerization reaction, an enzymatic reaction showing substrate inhibition, an enzymatic reaction showing product inhibition, a reaction showing precipitation of the substrate or of a reactant, the process comprising the steps of

• a) diluting a fresh substrate with solvent to form a diluted substrate-solvent mixture, and supplying this mixture to a reactor,
• b) causing the reaction medium in the reactor to react,
• c) discharging reaction mixture comprising reaction product, solvent, and substrate that has not reacted, to a first filtration membrane which is permeable to the solvent and impermeable to the substrate and to the catalyst or at least one of the reactants,
• d) returning solvent from the permeate side of the first membrane to dilute the fresh substrate, and
• e) returning retentate comprising substrate which has not reacted, from the first filtration membrane to the reactor.

The invention discloses a dark fermentation-light fermentation coupled biological hydrogen preparing process. According to the dark fermentation-light fermentation coupled biological hydrogen preparing process, a bipolar membrane electrodialysis unit is added behind a dark fermentation reactor, the components of the outgoing water obtained after dark fermentation are separated, thus the concentrated acetic acid is obtained, after pH regulation, the concentrated acetic acid is taken as incoming water of a light fermentation reactor, and meanwhile, the not utilized substrate is recycled and returns to the dark fermentation reactor to be reutilized. The product inhibition at the dark fermentation hydrogen production stage can be relieved, the pH of a fermentation system is controlled to be within the optimal range, the substrate is effectively recycled and reutilized, the total utilization ratio of the substrate is improved, the optimal substrate, namely, acetic acid is provided for the light fermentation hydrogen production stage, NH<4+> in the outgoing water obtained by dark fermentation is removed, then the inhibiting for the dinitrogenase of light fermentation bacteria is relieved, meanwhile, the interception and separation for the dark fermentation bacteria are completed, and the steps including centrifugalization, filtering and sterilization of the original process are replaced; the optimal hydrogen production conditions are provided for the dark fermentation and light fermentation stages, and the two-step coupled hydrogen production efficiency adopting the dark fermentation bacteria and the light fermentation bacteria is improved.

The present invention discloses one kind of bacterial strain for desulfurizing sulfur-containing heterocyclic ring compound in fuel oil. The bacterial strain is named as Mycobacterium ZD-19, and has the preservation number of CGMCC No. 1817. The present invention also discloses the specific desulfurizing use of eliminating sulfur-containing heterocyclic ring compound in fuel oil. By means of biological desulfurizing technology with the strain as the catalyst, sulfur-containing heterocyclic ring compound in fuel oil is degraded. The process of degrading dibenzothiophene and its derivative 4, 6-dimethyl dibenzothiophene follows one unique 'expanded 4S path', and the traditional 'expanded 4S path' products 2-hydroxy biphenyl and 3, 3'-dimethyl-2-hydroxy biphenyl are further methylated to produce final products 2-methoxyl biphenyl and 3, 3'-dimethyl-2- methoxyl biphenyl in effectively reduced product inhibition.

The invention belongs to the field of the biochemical industry and particularly relates to a method of improving the concentration of butanol in the process of acetone butanol fermentation. The method of improving the concentration of the butanol in process of the acetone butanol fermentation includes the following steps of adding a surface active agent to a culture medium in the process of the acetone butanol fermentation and extracting and improving the concentration of the butanol by means of micelle formed by the surface active agent. The method of improving the concentration of butanol in the process of the acetone butanol fermentation is directed against the product inhibition effect existing in the process of the acetone butanol fermentation and extracts the butanol by means of the micelle formed by the surface active agent serving as an extraction agent, relieving the inhibition effect in the process of the acetone butanol fermentation, increases the final concentration of the butanol in fermentation liquor, and therefore energy consumption of rectification in a later period is reduced.

The invention discloses an industrial fermentation tank for improving the yield of biosurfactin, which comprises a tank body and a fixing base, wherein the tank body is slidably connected with the top of the fixing base, a culture solution inlet is formed in the top of the left side wall of the tank body, an air outlet is formed in the top of the right side wall of the tank body, an acid storage box is arranged on the left side of the top of the tank body, an alkaline storage box is arranged on the right side of the top of the tank body, feeding ports are formed in the tops of the alkaline storage box and the acid storage box, guide pipes are communicated with the bottoms of the alkaline storage box and the acid storage box, spray heads are communicated with the ends, extending into an inner cavity of the tank body, of the guide pipes, a driving mechanism is arranged on the tank body between the alkaline storage box and the acid storage box, an air inlet pipe is communicated to the top part of the driving mechanism, and one end, extending to the inner cavity of the tank body, of the driving mechanism is connected with a rotating shaft. The design is reasonable, and the pH staged regulation and the overflow separation surfactant removal product inhibition are organically combined so as to obtain the maximum yield and the maximum yield of the fermentation production of the biological surfactant.

The invention discloses a technology for realizing high-yield polyoxins by continuous fermentation coupled with separation. The technology includes inoculating the polyoxins producing strain seed liquid into a fermentation cylinder to perform fermental cultivation, starting a membrane filter in the fermentation cylinder when the fermentation is at later stage of the logarithmic phase, making the fermentation broth containing polyoxins go through the membrane filter and enter a separating device out of the fermentation cylinder, collecting the broth to obtain a fermentation broth A, intercepting the bacterial cell in the fermentation cylinder to perform fermentation, feeding nitrogen source medium into the fermentation cylinder while starting the membrane filter in the fermentation cylinder to maintain steady fermentation system in the fermentation cylinder, performing continuous fermentation to the end, collecting the broth to obtain a fermentation broth B, and performing refining and purifying processing of the fermentation broth A and fermentation broth B to obtain polyoxins. The technology releases the product inhibition in the fermentation, reduces the viscosity of the fermentation broth, shortens the fermentation period, and improves the product titer. Moreover, the technology couples continuous fermentation with separation with feeding device and separating device, improves the utilization rate of the device, and reduces the production cost.