13 results about "Chloramphenicol" patented technology

The application discloses a dog-derived Enterococcus faecalis ZJUIDS-D016 with anti-aging effect and application, the dog-derived Enterococcus faecalis ZJUIDS-D016 is classified and named as (Enterococcus faecalis) Enterococcus faecalis ), and the preservation number is CGMCC 27038.The strain of the application is isolated from the intestinal tract of a healthy dog, has acid resistance, bile salt resistance and broad-spectrum antibacterial activity, and is sensitive to chloramphenicol, erythromycin and penicillin.The strain of the application has strong host adaptability, can colonize in the intestinal tract of a dog and secrete organic acids and bacteriocins, significantly inhibits the proliferation of common pathogenic bacteria such as dog pathogenic escherichia coli, effectively improves the intestinal health of pets and delays aging, and is suitable for preparing pet probiotic products.

The application discloses a kind of magnetic nano-enzyme microspheres and preparation method and application thereof, belong to the cross technical field of material, drug, rapid detection etc..The magnetic nano-enzyme microspheres take Fe3O4 microspheres as core, and platinum nanoparticles are in situ grown after being coated with dendritic mesoporous silica on the surface.The magnetic nano-enzyme microspheres of the application utilize magnetic response separation, high load content and enzyme catalytic amplification, greatly improve the detection sensitivity and signal strength, and are suitable for high-sensitivity detection of trace chloramphenicol and hexachlorobenzene.The qualitative detection cutoff value of chloramphenicol is 0.1 ng / mL, and the quantitative detection sensitivity is 0.0011 ng / mL.The quantitative detection sensitivity of hexachlorobenzene is 0.4 ng / mL.

This invention discloses a method for preparing a zirconium-based metal-organic framework@nickel-cobalt metal-organic framework oxygen reduction catalyst and its application in the removal of chloramphenicol. The method uses a nickel-cobalt metal-organic framework as a substrate, and fuses a zirconium-based metal-organic framework onto it via a hydrothermal method to form an octahedral zirconium-based metal-organic framework@nickel-cobalt metal-organic framework. This structure significantly improves the accessibility of adsorption sites and electrocatalytic active sites while maintaining the structural integrity of the metal-organic framework. The oxygen reduction performance was tested, and the system was coupled with an electroactive biofilm to determine the degradation efficiency of chloramphenicol within 244 hours. The results show that the zirconium-based metal-organic framework@nickel-cobalt metal-organic framework exhibits excellent oxygen reduction performance. In the modified microbial fuel cell, the degradation efficiency of chloramphenicol reached 90.31% within 244 hours, and the concentration decreased from 18.62 mg / L to 1.80 mg / L. This study provides a new approach for constructing efficient and stable metal-organic framework-based electrocatalysts, and has good application prospects in the fields of antibiotic wastewater treatment and environmental remediation.

The present application relates to the construction and application of the EcORep-based continuous directed evolution reporter system of aminoacyl-tRNA synthetase, and specifically, the reporter system comprises: a green fluorescent protein mutant sfGFP containing amber stop codon TAG N150TAG ; a chloramphenicol acetyltransferase mutant CAT containing amber stop codon TAG D112TAG ; a linear replicon containing aminoacyl-tRNA synthetase; a reporter plasmid containing a plus-strand mismatch DNA polymerase to continuously mutate the linear replicon, thereby generating an in-vivo library of aminoacyl-tRNA synthetase mutants; and a tRNA, which is orthogonal to the aminoacyl-tRNA synthetase and enables the incorporation of unnatural amino acids and the complete expression of proteins. The present application proves that the evolution reporter system can realize the efficient directed evolution of aminoacyl-tRNA synthetase, and further expands the application range of genetic code expansion technology.

This invention relates to a method for isolating Pichia pastoris. The method includes sample preparation: grinding a medium- and high-temperature fermented koji sample and then serially diluting it to obtain a bacterial suspension; selective plating: plating the bacterial suspension onto a selective culture medium; and high-temperature isothermal incubation: culturing the plated selective culture medium at 38℃-42℃ until single colonies grow; wherein the selective culture medium is YPD basal medium supplemented with chloramphenicol and acetic acid. This method effectively inactivates background bacteria, selectively enriches the target strain, and significantly increases the ethyl acetate yield of the obtained strain.

The application relates to the field of ophthalmic drugs, and particularly discloses an eye drop, which comprises the following components in mass fraction: 0.003%-0.2% of chlorhexidine gluconate; and 0.025%-0.05% of chloramphenicol. Since acanthamoeba usually feeds on bacteria, the chlorhexidine gluconate is used as a main component to kill acanthamoeba in the application, and the antibiotic chloramphenicol is added, so that the keratitis caused by bacterial infection can be avoided, the ocular surface bacteria can be killed, the nutrition source of acanthamoeba can be reduced, and the treatment of acanthamoeba keratitis can be synergistically strengthened.

To provide a novel antimicrobial product that enables the management of animal diseases while reducing reliance on conventional antibiotics. [Solution] The present invention relates to an antimicrobial composition comprising an extract of a coffee composition and an antibiotic, and to the use of the antimicrobial composition in the manufacture of antimicrobial drugs. The extract of the coffee composition comprises a solid component and water, the solid component comprising coffee beans and auxiliary materials. The antibiotic is selected from the group consisting of penicillin antibiotics, cephalosporin antibiotics, fluoroquinolone antibiotics, tetracycline antibiotics, chloramphenicol antibiotics, aminoglycoside antibiotics and combinations thereof, and the weight ratio of the coffee composition to the antibiotic is from 1.5:1 to 25000:1. The antimicrobial composition of the present invention can exhibit a superior antibacterial effect compared to the use of antibiotics alone, and this antibacterial effect can also be exerted against drug-resistant bacteria.

The application discloses a kind of Streptomyces for preventing and treating tomato bacterial disease, fermentation liquor and preparation method and application, and the Streptomyces for preventing and treating tomato bacterial disease is Streptomyces venezuelae FK-11, is preserved in China Microbial Culture Collection Center, the preservation number is CGMCC NO.25330, the preservation date is July 18, 2022, and the preservation address is No.3, Xili, Beichen, Beijing City, Chaoyang District.Compared with the prior art, the application provides a kind of soil antagonistic bacteria, which is a kind of Streptomyces that can produce chloramphenicol, isolated and selected from the surrounding of tomato root base, the fermentation liquor can effectively inhibit tomato bacterial disease, especially tomato bacterial canker disease and tomato bacterial wilt, it is derived from soil, and has strong environmental adaptability, and can effectively improve yield while inhibiting disease occurrence, the mode of action is fermentation liquor seed soaking, easy to operate, time-saving and labor-saving, environment-friendly, hope to replace chemical medicine, reduce chemical input, reduce environmental pollution, and guarantee the green and efficient production of tomato.

This invention discloses a method for quantitative detection of antibiotics in soil based on LC-MS / MS, comprising: freeze-drying a soil sample, weighing a trace amount of the freeze-dried powder, adding an extraction solution, extracting by vortexing and ultrasonication, centrifuging to collect the supernatant, concentrating to dryness by nitrogen blowing, redissolving and filtering, and then performing qualitative and quantitative analysis by high-performance liquid chromatography-tandem mass spectrometry. This invention eliminates the need for a solid-phase extraction column purification step, making the pretreatment operation simple and efficient. Only 0.1g of sample is required, and it exhibits high sensitivity, a low limit of quantitation, and uses an internal standard method to correct for matrix effects. The linear correlation coefficient R0 is high. 2 The spiked recovery rate is consistently between 80% and 120%, with a value >0.99, indicating that the method is accurate and reliable. This method can be used for the simultaneous or separate quantitative detection of more than 20 antibiotics, including chloramphenicol, tetracyclines, quinolones, and macrolides, in soil. It can also be directly extended to complex environmental matrices such as animal feces and sludge. It consumes little organic solvent and is environmentally friendly.

This invention discloses a chloramphenicol-specific nanobody and its applications, belonging to the field of food detection. The chloramphenicol-specific nanobody has the amino acid sequence shown in SEQ ID NO:1, or is a variant containing the recombinant protein of SEQ ID NO:1 and retaining chloramphenicol binding activity. The nucleic acid encoding the antibody, expression vector, host cell, and its applications are also disclosed. Based on this nanobody, this invention also provides a rapid detection method for chloramphenicol and a device for enriching chloramphenicol from complex samples such as poultry eggs. The nanobody provided by this invention has high affinity and strong specificity; the constructed test strip can achieve direct, rapid, and highly sensitive detection of poultry egg samples; the enrichment device can effectively concentrate trace amounts of chloramphenicol in large-volume samples without specialized equipment, showing broad application prospects for on-site monitoring and precise detection of chloramphenicol residues in food, especially poultry eggs.

This invention relates to a chiral preparation method for chloramphenicol. Specifically, the method uses p-nitrobenzaldehyde and glycine ester as starting materials, and an asymmetric aldol reaction occurs under the action of a pyridinium salt carbonyl catalyst. Following reduction and amidation reactions, chloramphenicol is obtained. Compared with existing technologies, this invention utilizes the strong catalytic ability of small-molecule pyridinium salt carbonyl catalysts, starting from inexpensive and readily available raw materials, to efficiently control the stereoselectivity of the aldol reaction, and to obtain the desired stereoconfiguration product, chloramphenicol, in a single dose. The preparation method of this invention reduces the protection of active groups, shortens the chiral synthetic route of chloramphenicol, is simple to operate, and is environmentally friendly.