20 results about "Precursor substance" patented technology

The invention discloses an ergothioneine-producing recombinant engineering bacterium as well as a construction method and application thereof, and belongs to the technical field of gene recombination fermentation. The method comprises the following steps: by taking escherichia coli as a starting bacterium, carrying out recombinant expression on a histidine trimethyl inner salt cysteine sulfoxide synthetase egt1 gene, an L-histidine methyltransferase egtD gene, a histidine trimethyl inner salt cysteine sulfoxide lyase egt2 gene, a methionine adenosine transferase metK gene, an adenylate kinase adK gene and an adenine phosphoribose transferase apt gene; on this basis, supply of precursor substances including histidine, cysteine and methionine is further improved through metabolic transformation, the yield of the finally obtained recombinant engineering bacterium for producing ergothioneine reaches 2.54 g / L after 48 h of shake-flask culture, the yield of a 5L fermentation tank reaches 18 g / L after further enlarged culture, the yield of ergothioneine is guaranteed while energy consumption and cost are reduced, and the method is suitable for industrial production. The method is suitable for practical popularization.

The present application provides a method for preparing a liposome composition. In the method, a containing step is provided, including: providing precursor liposomes wrapping a platinum drug precursor; and culturing the precursor liposomes in a salt solution to convert the platinum drug precursor into a platinum drug to obtain the liposome composition. The precursor liposomes are obtained by the following steps: hydrating the platinum drug to obtain the platinum drug precursor; and adding the platinum drug precursor to a lipid bilayer carrier to obtain the precursor liposomes. The liposome composition prepared by the method has better coating rate and stronger drug loading capacity.

The invention relates to the field of erbium complexes, in particular to a preparation method and application of a metal erbium complex. The chemical formula of the metal erbium complex is (C5H6N) [Er (tfac) 4], and tfac-is deprotonated 1, 1, 1-trifluoroacetylacetone. The metal erbium complex is prepared through solvent volatilization and slow diffusion and a low-temperature crystallization method, namely, an absolute ethyl alcohol solution of erbium chloride, 1, 1, 1-trifluoroacetylacetone and pyridine are added into a three-necked bottle according to the molar ratio of 1: 4: 1, then absolute ethyl alcohol is added, and heating and stirring are conducted; cooling to room temperature, collecting pink and transparent blocky crystals, washing with absolute ethyl alcohol, and drying in vacuum. The metal erbium complex has a remarkable quenching effect on bovine serum albumin in an ethanol solution, and can be used as a drug precursor; the bacteriostasis rate on escherichia coli is 93.36%, and the compound can be used as a bacteriostatic agent.

The invention discloses an AKR1C3 selectively activated small molecule drug conjugate and application of the AKR1C3 selectively activated small molecule drug conjugate. The invention discloses a series of compounds with a structure as shown in a general formula I, and also discloses application of the compounds in cancer treatment. The inventor evaluates the efficacy of the compound represented by the general formula I in treatment of various cancers by taking an in-vitro anti-tumor cell experiment as a carrier, and finds that the compound has good in-vitro activity and extremely high selectivity and can be used as a precursor substance for further development of a cancer treatment effect through selective activation of aldoketoreductase 1C3.

The invention relates to the technical field of chemical biological medicines, in particular to a preparation method and application of metal oxide hybrid hollow polydopamine microspheres. PSS is used as a hard template, metal ions and dopamine are adsorbed through static electricity, non-adsorbed metal ions are removed through dialysis, then the metal ions are oxidized into metal oxides through hydrothermal treatment, meanwhile, dopamine is subjected to self-polymerization to form polydopamine, and the composite material with the PSS as a core and the PDA as a shell is formed. A polydopamine-based core-shell structure with uniform size and controllable morphology of metal oxide particles is embedded, a hollow structure is formed along with etching of PSS and metal oxide, and a hollow structure with a nano plug is formed along with secondary coordination nucleation of metal ions after drug loading; due to the existence of the metal oxide, the stability of the adjustable structure of the prodrug is enhanced; the huge cavity structure is beneficial for increasing the drug loading capacity and the packaging efficiency of the anti-tumor small molecule drug; the composite material can realize directional delivery and efficient release of drugs.

The invention belongs to a mass spectrum technology, and particularly provides a sewage poison condition tracing method which comprises the following steps: A1, designing a tracing scheme according to poison condition abnormity of sewage sampling nodes, and the scheme comprises sampling nodes of sewage convergence countercurrent upward hierarchy; a2, collecting and analyzing the concentrations of drug protomers and metabolites thereof of raw water samples of all sampling nodes of the previous layer of the sampling nodes with abnormal toxicity conditions, and identifying the sampling nodes with abnormal toxicity conditions of the layer; circulating to the last-stage sampling node; a3, analyzing the sewage collection condition in the last-stage sampling node, and screening out a minimum building unit of a suspected poison source; and A4, entering the minimum building unit, collecting evidences, and determining the drug-related personnel. The method has the advantages of accurate and rapid tracing and the like.

The application belongs to the technical field of homogeneous catalysis, and discloses application of a ten-core 3d-4f supramolecular nanocage material in catalyzing a three-component Strecker reaction. The ten-core 3d-4f supramolecular nanocage material is used as a nanoreactor to realize synthesis of a biologically active drug precursor through the three-component Strecker reaction. The method has simple operation steps and can realize industrialized preparation. The prepared ten-core 3d-4f supramolecular nanocage material has high catalytic activity, catalytic stability and catalytic efficiency in catalyzing the three-component Strecker reaction.

Disclosed are a method for biological total synthesis of paclitaxel key precursor substance baccatin III, a biological material and use thereof. The bioenzyme composition used in the method comprises a taxane 9α-hydroxylase (T9αH) and a taxane C4-C20 oxetanase (TOT). According to the disclosure, a core component of a baccatin III biosynthetic pathway is identified, a baccatin III artificial synthesis route is constructed, thereby paving the way for efficiently developing a green low-carbon production pathway of taxane products (such as paclitaxel) through synthetic biology.

The application discloses a Saccharomyces cerevisiae de novo synthesis of naringenin engineering strain and a construction method and application thereof, and the engineering strain is constructed by modifying a genome of the Saccharomyces cerevisiae CEN.PK2-1C as follows: substrate competition pathway genes are knocked out, anti-feedback inhibition genes are overexpressed, and the like, so as to improve a metabolic flux j of a precursor substance tyrosine; tyrosine deaminase, 4-coumarate:CoA-ligase, chalcone synthase and chalcone isomerase are expressed heterogeneously, so as to realize de novo synthesis of naringenin. Finally, the yield of naringenin is further improved by high-efficiency expression of Sc4CL and HaCHS at multiple copy sites.

This invention relates to the field of pharmaceutical and chemical intermediates technology, and discloses a novel class of substituted phenylethyl-O-β-D-glucuronide compounds. These compounds are generated using substituted phenylethanol as a substrate and 1-fluoro-D-glucuronic acid as a glycosyl donor, catalyzed by β-glucuronyltransferase derived from *E. coli*. The process yield can reach over 95%, and the reaction conditions are mild and environmentally friendly. Substituted phenylethyl-O-β-D-glucuronide can be efficiently used for the determination of β-glucuronidase activity, and its applications are wide-ranging and reliable. The product can meet the needs of pharmaceutical, food, and other fields for β-glucuronidase activity control. It can be used for enzyme activity detection in the auxiliary diagnosis of clinical diseases, and also for enzyme quality control in fruit juice clarification processes in the food industry, drug precursor activation, and glycan structure analysis in the biopharmaceutical field. The product structure has been verified to be accurate by mass spectrometry and 1H NMR spectroscopy, and enzymatic hydrolysis experiments have confirmed its reliable application.

The invention relates to an anti-alcoholism composition, a liquid preparation with an anti-alcoholism effect and a preparation method and application of the liquid preparation, and belongs to the technical field of physiology. The anti-alcohol composition comprises an NAD (nicotinamide adenine dinucleotide) precursor substance and amino acid, and the NAD precursor substance is one or more of nicotinamide, nicotinamide ribose, nicotinamide mononucleotide or nicotinic acid; and the amino acid is one or more of L-glutamine, L-serine or L-lysine. The special combination of the NAD precursor substance and the amino acid can synergistically accelerate ethanol metabolism, and the alcohol effect dispelling liquid preparation prepared on the basis of the alcohol effect dispelling liquid preparation is flexible in use time, controllable in component and outstanding in alcohol effect dispelling effect, and has very wide application prospects.

The invention discloses an aldehyde ketoreductase 1C3 selective inhibitor with a tricyclic structure and application of the aldehyde ketoreductase 1C3 selective inhibitor. The invention discloses a series of compounds with a structure as shown in a general formula I, and also discloses application of the compounds in cancer treatment. The inventor evaluates the efficacy of the compound represented by the general formula I in treatment of various cancers by taking an in-vitro anti-tumor cell experiment as a carrier, and finds that the compound has good in-vitro activity and can be used as a precursor substance for further development of a cancer treatment effect by inhibiting AKR1C3.

The invention belongs to the field of microorganisms and fermentation engineering, and discloses recombinant escherichia coli for producing valerolactam as well as a construction method and application of the recombinant escherichia coli. The method comprises the following steps: firstly, modularly optimizing the expression level of a heterologous gene and optimizing a whole-cell catalytic reaction system by using promoter engineering; then, the catabolism of pyruvic acid and the synthesis path of L-lysine are modified, and the supply of precursor substances is enhanced, so that the recombinant escherichia coli realizes de novo synthesis of the valerolactam, and the synthesis efficiency of the valerolactam is remarkably improved. Compared with the prior art, the invention not only provides two methods of whole-cell catalysis and de novo synthesis of the valerolactam, but also effectively avoids the problem of environmental pollution generated in the chemical synthesis process, embodies the concept of green synthesis, and ensures that the yield of the valerolactam reaches a higher level even only at a shake flask level. Important application prospects are provided for efficient synthesis of valerolactam.

A bag (10) for producing a foam-in-bag dunnage material comprises a closed edge portion (16a-c) and, in a non- sealed state of the bag, an open edge portion (16d), the closed and open edge portions (16a-d) delimiting an inner bag volume (22). The invention proposes that a bag structure of the bag (10) comprises a mixing chamber (24) which is adapted to receive foam precursor substances, which is arranged within the inner bag volume (22), which is at least partially and initially delimited against the remainder (28) of the inner bag volume (22), and which in the non-sealed state of the bag (10) is connected to the open edge portion (16d).

The application belongs to the technical field of homogeneous catalysis, and provides application of a ten-core 3d-4f supramolecular nanocage material in catalyzing a three-component aza-Darzens reaction. The application comprises the following steps: mixing an aldehyde compound, an amino benzene compound, ethyl diazoacetate, the ten-core 3d-4f supramolecular nanocage material and an organic solvent, and then performing a reaction to obtain a reaction product, namely completing the three-component aza-Darzens reaction. The ten-core 3d-4f supramolecular nanocage material is used as a catalyst to catalyze the three-component aza-Darzens reaction to realize synthesis of a drug precursor with biological activity, and the catalyst has high catalytic efficiency, the operation steps are simple, and the yield of the target product is also high.

The invention discloses a central targeting tacrine conjugate based on a transporter as well as a preparation method and application of the central targeting tacrine conjugate. The structures of the central targeting tacrine conjugate based on the transporter are shown in general formulas I and II. According to the invention, cholinesterase inhibitory activity, transport penetration experiment, cytotoxicity and blood brain distribution are taken as evaluation indexes, and the potential of the compound in treatment of Alzheimer's disease is systematically investigated. Experimental results show that the compound shows good in-vitro safety, remarkable cholinesterase inhibitory activity and excellent blood-brain barrier permeability, and can be further developed into a precursor substance for resisting Alzheimer's disease with central targeting.

This invention discloses a method for increasing the yield of acetylglucosamine in Bacillus subtilis. The method involves knocking out and verifying the key phosphatase YwpJ, which catalyzes the dephosphorylation of GlcNAc-6-P to generate GlcNAc. Overexpression of YwpJ reduces the excessive accumulation of intracellular phosphate sugars, eliminating the toxic effects of excessive phosphate sugars on cells and effectively secreting phosphate sugars extracellularly, thereby improving cell growth. Furthermore, knocking out the key genes murQ and nagBB in the GlcNAc synthesis precursor degradation pathway blocks the degradation of precursor substances, reduces carbon flux waste, and allows more carbon flux to be converted into products. Ultimately, the GlcNAc yield of the recombinant strain FMIP34 reached 26.1 g / L, an increase of 61.1%, and the GlcNAc conversion rate reached 0.483 g / g glucose.

The application provides an alpha-ketone amide peroxide responsive drug precursor compound and a preparation method and application thereof, relates to the field of chemical biotechnology, and the alpha-ketone amide peroxide responsive drug precursor compound in the application is broken under the action of hydrogen peroxide, releases diethyl dithiocarbamate after chemical structure is changed and a benzyl group is eliminated, the released product is combined with copper ions to generate the metal drug copper diethyl dithiocarbamate CuET, and has a remarkable inhibiting growth effect on malignant tumor cells. The prepared drug precursor compound has a simple and easy-to-operate synthesis method, is strong in controllability, and has a wide application prospect in the field of malignant tumor treatment using the responsive drug precursor compound.

This invention discloses a recombinant engineered bacterium producing ergothioneine, its construction method, and its application, belonging to the field of gene recombination fermentation technology. This invention uses *Escherichia coli* as the starting bacterium to recombinantly express histidine trimethylammonium cysteine ​​sulfoxide synthase. egt1 Gene, L-histidine methyltransferase egtD Gene, histidine trimethyl inner salt cysteine ​​sulfoxide lyase egt2 Gene, methionine adenosine transferase metK Gene, adenosine kinase adK Genes and adenine phosphoribosyltransferase apt The gene was modified, and further metabolic modification was used to increase the supply of precursor substances histidine, cysteine, and methionine. The resulting recombinant engineered ergothionein-producing bacteria achieved a yield of 2.54 g / L after 48 h of shake-flask culture, and a yield of 18 g / L after further expansion to a 5L fermenter. This method reduces energy consumption and costs while ensuring ergothionein production, making it suitable for practical application.

The invention discloses a method for evaluating generation of by-product NDMA (N-dimethylaminoacetic acid) of a precursor substance in chloramine disinfection, which comprises the following steps: collecting data of NDMA generated by a drug precursor and a flocculant precursor in the chloramine disinfection process, converting original independent variables and dependent variables into secondary power and logarithmic forms by using SPSS, and performing regression analysis by using a stepping method; the variables with the parameter significance P larger than 0.1 are removed, and the remaining variables are input into the SPSS again to obtain a regression model; and measuring or calculating the precursor substance concentration, chloramine concentration, pH, temperature and reaction time in a specified environment, and substituting into the regression model to calculate the NDMA generation amount of the specified precursor substance under a certain condition. According to the method, the generation condition of the NDMA in the monochloramine disinfection process can be accurately calculated, and the generation amount of the NDMA in a water plant can be fed back in real time according to different water qualities, so that the condition that the concentration is too low and cannot be measured is avoided, the generation of the NDMA can be dynamically guided, and the method is efficient, convenient and practical.