161 results about "Gram negative bacterium" patented technology

The invention discloses a lactobacillus rhamnosus capable of improving joint inflammation and promoting bone health, a metagen and application of the lactobacillus rhamnosus, the lactobacillus rhamnosus is lactobacillus rhamnosus BN02, the lactobacillus rhamnosus is preserved in China General Microbiological Culture Collection Center on November 27, 2023, and the preservation number is CGMCC No.29133. The lactobacillus rhamnosus can be used for improving joint inflammation and promoting bone health. The lactobacillus rhamnosus BN02 can reduce the number of gram-negative bacteria in intestinal tracts of arthritis patients, increase the synthesis amount of bone collagen, and is beneficial to promoting absorption of vitamin C by the intestinal tracts, improving joint inflammation and promoting bone health.

An antibacterial polymer having a molecular weight above a certain level, which is highly miscible with other polymers compared to a monomolecular type antibacterial agent and can be added during the melt extrusion process. Further the antibacterial polymer has the advantage of exhibiting excellent antibacterial properties against Gram-negative bacteria and does not elute over time.

The present invention discloses a strong, non-toxic, antibacterial and antiviral nano-functional material and a preparation method thereof. The nano-functional material is green, non-toxic and harmless, and its antibacterial and antiviral effect can reach more than 99%. The new nano-material innovatively uses the natural antibacterial agent meta-dichlorostyrene meta-dichloroacetophenone as the main body of the material to exert its antibacterial and antiviral effects. This makes the new nano-material not only have extremely strong antibacterial and antiviral effects, but also as a natural antibacterial agent, when it is used as a textile material, it can be non-toxic and harmless to the human body, green and healthy. It has a better inhibitory effect on both Gram-negative and Gram-positive bacteria than nano-copper oxide and meta-dichlorophenylethanol and meta-dichloroacetophenone. The present invention also provides a preparation method for the nano-functional material, which includes chemical reaction processes such as boron hydrolysis reaction, catalytic oxidation reaction, electrocarboxylation reaction, and esterification reaction.

The invention discloses a bacteriophage lyase and application thereof, and particularly relates to a bacteriophage lyase with an amino acid sequence as shown in SEQ INNO.2. The bacteriophage lyase can inhibit the growth of escherichia coli, staphylococcus and salmonella, can be used as an antibacterial substance in splitting gram-negative bacteria and can be used for preparing drugs for resisting gram-negative bacteria. The lyase can be used independently or compounded with other substances, the use concentration of antibiotics can be reduced by combining the lyase with the antibiotics, toxic and side effects (such as renal toxicity of polymyxin) of drugs are reduced, and meanwhile, generation of bacterial drug resistance is delayed. After the lyase and the chitosan are combined for use, remarkable antibacterial activity is generated, the antibacterial effect can be achieved without pre-treatment on bacteria, and the practicability is improved.

The invention belongs to the field of genetic engineering and biological treatment, and provides an eukaryotic expression vector, gram-negative bacteria containing the eukaryotic expression vector and application of the eukaryotic expression vector in preparation of tumor drugs. By selecting and combining a phage-derived promoter, a specific phage RNA polymerase gene, a membrane rupture protein gene and an eukaryotic expression drug protein gene, an eukaryotic expression vector is divided into three modules: (1) a phage-derived RNA polymerase gene transcription module; (2) a membrane rupture protein gene expression module; and (3) a eukaryotic drug protein gene expression module. Through organic combination of the three modules, the eukaryotic drug delivery system is constructed, and the system and method for stably and efficiently performing eukaryotic drug protein expression, drug delivery and drug killing are realized.

The invention provides an antibacterial peptide and application thereof in resisting bacteria and / or enhancing the disease resistance of plants. Specifically, on one hand, the invention provides two antibacterial peptides which are novel functional antibacterial peptides ZJUAMP3 and ZJUAMP4, sequences of the novel functional antibacterial peptides ZJUAMP3 and ZJUAMP4 are respectively shown as SEQ ID NO: 1 and SEQ ID NO: 2, and the antibacterial peptides ZJUAMP3 and ZJUAMP4 both have broad-spectrum antibacterial activity, have good antibacterial activity on bacteria such as gram-negative bacteria, gram-positive bacteria and fungi, and are suitable for scenes needing sterilization or fungus and bacterium growth inhibition. Besides, the ZJUAMP4 can activate an MAPK signal channel in a plant body and induce the plant to generate systematic disease resistance, and is suitable for the fields of crop disease prevention and control and plant protection. The antibacterial peptide is simple in structure and easy to synthesize.

The invention relates to an antibacterial peptide LK-KJT-B01 for gram-negative bacterium infection and a preparation method and application thereof.The antibacterial peptide LK-KJT-B01 can be extracted from bacillus laterosporus, has the advantages of being broad in spectrum, safe, free of toxicity and the like, has a very strong bactericidal effect on gram-negative bacterium infection, and can be used for preparing antibacterial peptide LK-KJT-B01 for gram-negative bacterium infection. Particularly, the sensitivity to carbapenem-resistant gram-negative bacteria is high, and the application prospect is very wide.

The invention discloses a preparation method and application of sodium gallate-polyphenol chitosan antibacterial hydrogel, firstly, gallic acid and sodium acetate are used as raw materials, a high-purity sodium gallate complex 5-carboxyl-2, 3-sodium dihydroxyphenolate is prepared at normal temperature and normal pressure, then a polyphenol compound and chitosan are cross-linked through Schiff base reaction, and the sodium gallate-polyphenol chitosan antibacterial hydrogel is obtained. And finally, carrying out rotary evaporation treatment, so that the sodium gallate is loaded in the polyphenol chitosan hydrogel system to obtain the antibacterial hydrogel. Sodium gallate is used as a functional component, uniform loading of sodium gallate in a polyphenol chitosan hydrogel system is realized through dual effects of physical adsorption and chemical bonding, the loading mechanism can effectively avoid aggregation and burst release of sodium gallate, stable release of antibacterial components is ensured, and the antibacterial property of the hydrogel is improved. The slow release time of the antibacterial hydrogel under the conditions that the pH values are 5.5 and 7.2 respectively exceeds 24 hours; and the antibacterial hydrogel has an inhibition effect on both gram-positive bacteria and gram-negative bacteria.

The present invention relates to a pharmaceutical composition for use against Gram-negative bacteria comprising at least one efflux pump inhibitor and at least one antibiotic. The invention also relates to the use of said pharmaceutical composition for resisting microorganisms, in particular bacteria, in particular gram-negative bacteria.

The present invention is predicated on success at producing a substance that results from removing LPS from a plant fermentation extract and the discovery that said substance demonstrates a biological activity that cannot be explained by conventional scientific common knowledge. The present invention is a method for obtaining an LPS-removed plant fermentation extract, an LPS-removed plant fermentation extract that is obtained using said method, and a formulation in which said LPS-removed plant fermentation extract has been compounded, said method being characterized by comprising a step in which LPS is removed from a plant fermentation extract that is obtained by fermenting a material derived from an edible plant, using a facultative anaerobic gram-negative bacterium that is exclusively symbiotic with the plant, and simultaneously cultivating said facultative anaerobic gram-negative bacterium.

The present application relates to the technical field of polysaccharide modification, and specifically discloses amino acid modified astragalus polysaccharide, a preparation method thereof and antibacterial application. The present application uses astragalus polysaccharide, formaldehyde and specific amino acids as raw materials, and prepares amino acid grafted modified astragalus polysaccharide through a Mannich reaction. The amino acid grafting site only occurs on the fifth carbon of the sugar ring. Not only does this retain the amino and carboxyl groups of the amino acid, so that the biological activity of the amino acid is retained, but also the active carboxyl group of the astragalus polysaccharide can be retained, so that the antibacterial property of the synthesized amino acid modified astragalus polysaccharide is significantly improved, and broad-spectrum antibacterial property can be achieved. The amino acid modified astragalus polysaccharide has excellent antibacterial activity on gram-positive bacteria and gram-negative bacteria, is a green new type of efficient antibacterial material, and is expected to become a substitute for antibiotics. The amino acid modified astragalus polysaccharide has important significance for solving the problems of increasing bacterial drug resistance and environmental accumulation caused by antibiotics, and has good application prospect.

The present invention belongs to the field of microbiology, and particularly relates to membrane vesicles (MVs) isolated from bacteria, and an isolation and preparation system and method for the membrane vesicles, and applications of the membrane vesicles. The bacteria of the present invention comprise Gram-positive bacteria and Gram-negative bacteria. The invention uses ionizing irradiation to irradiate bacteria, and isolates and purifies the produced membrane vesicles. The membrane vesicles prepared can be used as a vaccine, a vaccine adjuvant and / or a pharmaceutical carrier. In addition, the present invention provides a biological composition comprising the membrane vesicles and inactivated bacteria. In addition, the present invention also provides a preparation system, and isolation and purification system for bacterial membrane vesicles and the corresponding method. The membrane vesicles obtained by using the system and method have high yield, high purity and easy to be industrialized.

The application discloses a kind of implant and its preparation method and application, the implant includes material body, metal oxide layer and mixed crystal layer, the mixed crystal layer is located the surface of the metal oxide layer;The metal oxide layer includes metal oxide nanorod array;The metal oxide is selected from zinc oxide, silver oxide or its combination;The mixed crystal layer includes CaP crystal and metal oxide crystal.The implant of the application is sterilized by the bacteriostatic metal ion generated by physical puncture and degradation of metal oxide nanorod, has good antibacterial effect to gram-positive bacteria and gram-negative bacteria, prevents infection;It can also relieve post-implantation inflammatory response, reduce immune response under post-implantation infection, shorten wound healing time.In addition, due to the coating effect of mixed crystal layer on metal oxide layer, the bacteriostatic metal ion is slowly released, the release time is long, and long-lasting antibacterial effect can be achieved, and post-implantation inflammatory response can be reduced.

The invention provides a compound of formula (I) or a salt thereof, wherein R1-R3, X and L have any of the values described in the specification, as well as compositions comprising a compound of formula (I). The compounds are useful as antibacterial (e.g., Gram-negative bacteria) agents.

The invention discloses a preparation method of a tobacco stem extract and application of the tobacco stem extract as a microbial corrosion inhibitor, and belongs to the field of metal microbial corrosion and protection.The preparation method comprises the steps that collected tobacco stems are cleaned, aired and ground into powder to obtain tobacco stem powder, the tobacco stem powder is dispersed in an ethanol water solution to be soaked, then the solution is filtered, and filtrate is concentrated; and drying to obtain the tobacco stem extract. Antibacterial and corrosion characterization experiments prove that when the concentration of the tobacco stem extract reaches 200mg / L, a broad-spectrum antibacterial effect on gram-negative bacteria and gram-positive bacteria can be achieved, initial adhesion of microorganisms on the metal surface is effectively inhibited, a formed mature biofilm is eliminated, and an obvious inhibition effect on microbial corrosion is achieved. The raw materials of the tobacco stem extract are cheap and easy to obtain, the preparation method is simple, the process is green and environment-friendly, the antibacterial and corrosion inhibition effects are remarkable, and efficient prevention and control of metal material microbial corrosion in the environment can be achieved.

The present application relates to the technical field of medical bandage, and discloses a biomass antibacterial hemostatic bandage and a functionalization method thereof.The bandage comprises a bandage base material and a composite antibacterial functional layer loaded thereon, the functional layer is composed of a composite antibacterial unit and lysozyme, and the composite antibacterial unit comprises a cationic antibacterial core, a polyphenol sustained-release shell and an enzymatic cellulose scaffold.The present application forms a biomass antibacterial hemostatic bandage with broad-spectrum, long-acting, low drug resistance and hemostatic function by constructing a cationic antibacterial core-polyphenol sustained-release shell-enzymatic cellulose scaffold composite antibacterial unit and synergistically loading lysozyme.The bandage shows significant technical advantages in dealing with complex wound infection, especially gram-negative bacterial infection and drug-resistant bacterial challenge, and provides an efficient and safe solution for clinical wound management, and has important clinical application value and broad market prospect.

The invention discloses a long-acting antibacterial PP composite material for a cleaning brush and a preparation method, and relates to the technical field of antibacterial PP. The invention relates to a long-acting antibacterial PP composite material for a cleaning brush. The long-acting antibacterial PP composite material is prepared from the following components in parts by mass: 60-80 parts of polypropylene resin, 5-15 parts of polyisobutene, 15-30 parts of inorganic filler, 0.5-2.0 parts of an antibacterial agent, 3-8 parts of a migration enhancer, 0.5-1.5 parts of an antioxidant, 0.5-1.5 parts of a lubricant and 0.1-0.5 part of a nucleating agent. The long-acting antibacterial PP composite material for the cleaning brush has excellent antibacterial performance. The antibacterial agent is unique in structural design and can efficiently destroy bacterial cell membranes, so that a broad-spectrum antibacterial effect is achieved. Gram-positive bacteria and Gram-negative bacteria can be effectively inhibited, and the problem that a traditional PP material is insufficient in antibacterial performance is solved.

An effective treatment method for a broad variety of diseases in both animals and humans is disclosed. The method includes combining one or more vaccines with a treatment compound to enhance vaccine efficacy. The disclosed treatment compound does not act directly on the pathogen, and thus the organisms cannot readily develop resistance to the treatment. When a compound such as, but not limited to, the disclosed compound is used in conjunction with one or more vaccines, a synergistic effect is realized. The suggested compound is derived from a lipopolysaccharide (LPS) of gram negative bacteria. The treatment compound is combined with one or more appropriate vaccines and is administered early in the life of an animal to achieve a synergistic effect compared with the use of the treatment compound or the vaccine alone.

The invention provides a beta-diketoamide compound and application thereof in preparation of a gram infection resistant drug, the structural formula of the beta-diketoamide compound is as shown in formula (1), in the formula (1), R1 is H or halogen; r2 is nitro, alkyl, halogen or methoxyl. The beta-diketoamide compound disclosed by the invention comprises gram-positive bacteria such as staphylococcus aureus, enterococcus faecalis, enterococcus faecium and staphylococcus epidermidis and other clinical isolates, and shows antibacterial activity; after being combined with polymyxin, the compound has synergistic bacteriostatic activity on gram-negative bacteria such as acinetobacter baumannii, klebsiella pneumoniae, escherichia coli and pseudomonas aeruginosa, and can remove biofilms formed by staphylococcus aureus and enterococcus faecalis.

The invention discloses application of bacteriophage lyase LysFEC14 in preparation of a composition for resisting gram-negative bacteria. The amino acid sequence of the bacteriophage lyase LysFEC14 is as shown in SEQ ID NO.01. The invention further discloses a preparation method of the bacteriophage lyase LysFEC14. The antibacterial composition disclosed by the invention shows high-efficiency cracking activity on various escherichia coli standard strains, still has a remarkable antibacterial effect at low concentration, and provides a green and efficient novel antibacterial composition for preventing and treating gram-negative bacterium infection, particularly drug-resistant escherichia coli infection.

The invention discloses a carbapenem drug resistance marker screening method and system based on a cross-species compressed Debrueine diagram and a medium. The method comprises the following steps: starting from whole genome sequencing data of gram-negative bacteria belonging to different species and carbapenem drug phenotypes of the gram-negative bacteria, constructing a compressed Debrueine graph based on cross-species joint data, and taking existence / deletion of nodes in the graph as unified genetic variation characteristics. Performing correlation analysis on the nodes and the drug resistance phenotypes by using a linear hybrid model to obtain a candidate node set related to the phenotypes; k-mer is extracted based on the candidate node sequence, and secondary statistical screening is completed in combination with chi-square test and mutual information; and finally determining a group of carbapenem drug-resistant genetic markers which can be applicable across species through a hierarchical feature selection strategy of random forest and XGBoost. Efficient dimension reduction of large-scale cross-species genome data, cross-species consistent variation representation and high-interpretability marker screening are achieved.

The invention discloses an application of combination of lefamulin and polymyxin B in preparation of a bactericide. According to the invention, lefamorin and polymyxin B are used for synergistically killing bacteria, so that the antibacterial activity of polymyxin B on gram-negative bacteria which are drug-resistant and sensitive to polymyxin B, such as escherichia coli, klebsiella pneumoniae and the like, can be effectively recovered in vitro and in vivo; in addition, lefamoline has no cytotoxicity to mammalian cells, and the application of lefamoline effectively reduces the therapeutic dose of polymyxin B and reduces the side effect risk of polymyxin B to mammals.

The present invention relates to an antimicrobial composition, more particularly a liquid composition that is not harsh on the surfaces being cleaned. This invention is especially useful in killing both gram positive as well as gram negative bacteria both of which can cause health problems. This is achieved by combining an amino acid surfactant with an alkanediol and a chelating agent, none of which in themselves have any significant antimicrobial efficacy.

This invention relates to an endogenous antimicrobial peptide from bovine milk and its applications. The antimicrobial polypeptide compound VAVALARPKHPIK is derived from endogenously enzymatically hydrolyzed bovine casein, with the amino acid sequence Val-Ala-Val-Ala-Leu-Ala-Arg-Pro-Lys-His-Pro-Ile-Lys. It exhibits broad inhibitory activity against both Gram-positive and Gram-negative bacteria, including *Porphyromonas gingivalis*, *Escherichia coli*, and *Staphylococcus aureus*. This antimicrobial peptide shows promising applications as a health supplement and / or medical device or pharmaceutical for the prevention and / or reduction of infectious diseases, as a food antimicrobial agent, in novel functional foods, pet food and animal feed additives, and in daily chemical products.

The present application relates to a kind of chlorella-nanose complex hydrogel and its preparation method and application, belong to nanose antibacterial technical field.The chlorella-nanose complex hydrogel includes hydrogel matrix, and the chlorella and photo-thermal nanose loaded on the hydrogel matrix.The present application also provides the preparation method of the complex hydrogel, and the application in the preparation of antibacterial drug or dressing and the killing gram-negative bacteria and gram-positive bacteria.The present application combines chlorella and nanose for the first time, and constructs a self-oxygen supply antibacterial platform.The chlorella in the chlorella-nanose complex hydrogel can carry out photosynthesis under illumination, continuously produce oxygen, provide sufficient substrate for nanose oxidase-like reaction, overcome the low activity defect of traditional nanose in anoxic environment.

The invention discloses a bacterial outer membrane mixed vesicle carrier, the mixed vesicle is a mixed membrane structure formed by fusing two heterotype bacterial outer membrane vesicles, and the two heterotype bacteria are respectively gram-positive bacteria and gram-negative bacteria. The mixed vesicle carrier can simulate a natural internalization path of pathogenic bacteria (G < + > / G <->) invading cells, accurately locks cells which are easily invaded by bacteria, can identify corresponding homologous bacteria surfaces, efficiently enriches drugs at bacterial infection parts, and effectively improves treatment on mixed bacterial infection parts.

The present invention relates to a method for treating Gram-negative bacteria that are resistant to colistin (MIC > 50 mg / mL), an antibacterial compound, excluding those of the genera Burkholderia, Proteus, and Serratia, comprising contacting the bacteria with an aqueous pharmaceutical composition containing a rose bengal (RB) compound of formula I, dissolved or dispersed at a concentration of about 0.01 to about 15 mg / mL, and irradiating the contacted bacteria with light of a wavelength of about 500 nm to about 600 nm for a period of about 1 to about 10 minutes, at a concentration of about 16 to about 160 J / cm². 2 The aim is to create a method that involves obtaining a certain amount of light to treat and kill irradiated bacteria. [Formula 1] JPEG2026511692000028.jpg5864 (where X, R 1 , R 2 (and M+ are defined herein)

The application belongs to the technical field of biological medicine, and relates to an antibacterial polypeptide, a composition and application thereof. The amino acid sequence of the antibacterial polypeptide is shown in SEQ ID NO. 1: KWKIKWPVKWFKM-NH2. Experiments show that the antibacterial polypeptide has broad-spectrum antibacterial activity on gram-positive bacteria and / or gram-negative bacteria, and simultaneously has low cytotoxicity and low hemolyticity. The antibacterial polypeptide provided in the application is composed of 14 amino acids, the polypeptide chain is short, the molecular weight is small, and the antibacterial polypeptide is easy to be artificially synthesized, is a small-molecule polypeptide with high application value, and can be used for preparing a novel antibacterial agent, and has wide application prospects.

The present application relates to the technical field of antibacterial technology, and particularly relates to a natural antibacterial agent and application thereof. The present application provides a method for preparing a composite antibacterial preparation by using Chinese medicine pomegranate peel and Bacillus subtilis AC-1 as raw materials. The composite antibacterial agent has the characteristics of strong resistance to gram-negative bacteria Escherichia coli, gram-negative bacteria Staphylococcus aureus, Staphylococcus pseudintermedius, pathogenic fungus Gymnoascus ruber, Microsporum canis and Microsporum gypseum.

The application discloses a CXCL-BPI fusion protein which can be used for treating gram-negative bacterial infection, a coding nucleic acid of the CXCL-BPI fusion protein, an expression preparation method, and application of the CXCL-BPI fusion protein to preparation of a pharmaceutical composition for treating gram-negative bacterial infection. The CXCL-BPI fusion protein comprises a human ELR+CXC chemokine and a human BPI N-terminal domain functional fragment, has the functions of combining LPS, directly killing gram-negative bacteria and chemotactic cell migration, and also has the functions of promoting phagocytes to be guided to combine and phagocytize gram-negative bacteria, and the action mechanism can overcome gram-negative bacterial drug resistance.