58 results about "Polymyxin B" patented technology

The invention belongs to the technical field of gene engineering, and particularly relates to a mutant of polymyxin efflux transporter and application of the mutant. The mutant is a PmxD transporter mutant, the amino acid sequence of the PmxD transporter mutant is shown as SEQ ID NO: 1, and compared with wild type PmxD, the polymyxin transport capacity of the PmxD transporter mutant (T38W) is improved by 450.46%; and the total discharge amount of polymyxin is increased by 85.72%. Meanwhile, the mutant can significantly improve the growth ability of the strain on a plate containing 250 [mu] g / mL of polymyxin B, namely significantly improve the autoresistance of paenibacillus polymyxa to polymyxin.

The invention discloses an application of NSC348884 in preparation of an antibacterial drug, the bacteria of the NSC348884 are gram-negative bacteria or drug-resistant gram-negative bacteria, and the gram-negative bacteria are acinetobacter baumannii, escherichia coli, pseudomonas aeruginosa or klebsiella pneumoniae; based on an antibacterial drug high-throughput screening technology, it is found from 1280 small molecule compounds that the benzimidazole compound NSC348884 has direct bacteriostasis and sterilization effects on gram-negative bacteria and drug-resistant gram-negative bacteria, and no drug resistance is generated after the benzimidazole compound NSC348884 is continuously applied for 14 days. Further research shows that NSC348884 can interfere with lipid synthesis of gram-negative bacterium cell membranes, inhibit formation of biological membranes and induce lipid metabolism disorder, so that bacteriostatic and bactericidal effects are achieved. In addition, the NSC348884 can also enhance the sensitivity of the drug-resistant bacteria to the imipenem and the polymyxin B.

The invention provides a pharmaceutical composition, glycyrrhizic acid and polymyxin B self-assembled carrier-free hydrogel as well as a preparation method and application thereof, and belongs to the technical field of biological medicines. The invention provides a pharmaceutical composition. The pharmaceutical composition comprises glycyrrhizic acid and polymyxin B. According to the pharmaceutical composition, the inhibition effect on MRSA is enhanced through drug combination, the use of polymyxin B is reduced through the synergistic effect, and the development pressure of antibiotic drug resistance is relieved. According to the hydrogel formed by crosslinking the glycyrrhizic acid and the calcium chloride, the glycyrrhizic acid and the calcium chloride are crosslinked to form the hydrogel, and the calcium chloride is introduced into a glycyrrhizic acid system to increase the mechanical strength of the glycyrrhizic acid hydrogel, so that the glycyrrhizic acid hydrogel can be better attached to a wound. The invention provides a glycyrrhizic acid and polymyxin B self-assembled carrier-free hydrogel and a preparation method of the glycyrrhizic acid and polymyxin B self-assembled carrier-free hydrogel. The hydrogel does not contain any inert carrier component at all, the drug loading rate of 100% is achieved, and adverse reactions possibly caused by a traditional carrier system are effectively avoided.

The invention discloses a preparation method of engineered bacteria for releasing CO gas under initiation of ultrasonic waves to kill tumor cells, and relates to a preparation method of CO carrier engineered bacteria. The invention aims to solve the problems that the existing CO carrier material is low in delivery efficiency, the CO is difficult to release efficiently and controllably in space and time at the same time, and the existing metal CO carrier material is high in toxicity. Meanwhile, the problems that the penetrating power of light waves to biological tissues is limited, and the CO release efficiency is limited due to a tumor hypoxic microenvironment are solved. The preparation method comprises the following steps: 1, modifying the surface of escherichia coli with 3-hydroxyflavone-D-alanine; and 2, continuously modifying the surface of the escherichia coli with CaO2 (at) polymyxin B. The method is used for preparing the engineered bacteria for releasing the CO gas through ultrasonic initiation to kill the tumor cells.

The invention belongs to the technical field of biology, and provides a pseudomonas aeruginosa endotoxin specific binding polypeptide and application thereof. The amino acid sequence of the polypeptide is shown as SEQ ID No. 1, SEQ ID No. 3 or SEQ ID No. 4 in a sequence table. Experiments prove that the polypeptide has excellent affinity with pseudomonas aeruginosa endotoxin, and compared with an existing anti-endotoxin clinical drug polymyxin B, the polypeptide has obviously better pseudomonas aeruginosa endotoxin detoxification capability. On the basis, the invention further provides application of the polypeptide in removal or separation or analysis of the endotoxin of the pseudomonas aeruginosa and application of the polypeptide in preparation of a detoxification medicine for the endotoxin of the pseudomonas aeruginosa. The polypeptide can be widely applied to the biomedical fields of biological separation, biological detection, disease diagnosis and treatment and the like.

The present application relates to the technical field of biology, and particularly relates to a mesenchymal stem cell culture medium and a preparation method and application thereof.The mesenchymal stem cell culture medium comprises a basic culture medium, fetal bovine serum, basic fibroblast growth factor, polymyxin B and deionized water.The present application can simultaneously improve the proliferation activity of mesenchymal stem cells and the secretion performance of HGF by simultaneously adding the basic fibroblast growth factor and the polymyxin B in the basic culture medium; more stem cells can be in the active proliferation and division process by limiting the content of the basic fibroblast growth factor in the mesenchymal stem cell culture medium to 5-50 ng / mL; and the secretion performance of HGF can be improved while the cell proliferation activity is maintained by limiting the content of the polymyxin B in the mesenchymal stem cell culture medium to 50-100 mu g / mL.

The application discloses a flagellum inhibiting peptide of pseudomonas aeruginosa and a preparation method and application thereof, and the sequence of the flagellum inhibiting peptide is Lys-Ile-Gly-Leu-Phe-Arg-Trp-Arg. The synthetic inhibiting peptide has a time-dependent self-assembly ability, can gradually evolve from scattered granular into filamentous structure, and finally forms a stable net-like morphology. The synthetic inhibiting peptide can significantly inhibit the flagellum motility of PAO1 and other strains of pseudomonas aeruginosa, and has synergistic antibacterial activity when combined with allicin, ciprofloxacin, meropenem, levofloxacin, polymyxin B and the like. Moreover, the synthetic inhibiting peptide has obvious bacteriostatic and healing-promoting effects on burn wound infection.

This invention provides a compound drug for treating melioidosis, its preparation method, and its application. The drug comprises active components of traditional Chinese medicine, a bioactive preparation, and a pharmaceutically acceptable carrier. The active components of traditional Chinese medicine are primarily extracts of Scutellaria baicalensis, Coptis chinensis, Fagopyrum dibotrys, and Polygonum cuspidatum. The bioactive preparation includes polymyxin B, homoserine lactonease, and recombinant human β-defensin 3. The components work synergistically to construct a comprehensive intervention system covering all pathological stages, including biofilm disruption, sterilization, anti-endotoxin activity, intracellular bacterial clearance, immune regulation, and tissue repair. This system can effectively disrupt bacterial biofilms, kill multidrug-resistant strains, neutralize endotoxins, and eliminate latent intracellular bacteria, addressing the core pain points of existing melioidosis treatments, such as strong drug resistance, significant toxic side effects, and high recurrence rates. The preparation process of this invention is carried out under low-temperature and sterile conditions throughout, which fully preserves the stability of the active ingredients, making it suitable for industrial production. The drug can be prepared in various dosage forms, covering all clinical subtypes of melioidosis, and possesses clinical application value and promising prospects for widespread application.

The application provides a polymyxin B-loaded nano preparation and a preparation method and application thereof, and belongs to the field of biological nanotechnology.The method comprises the following steps: (1) preparing a water-in-oil emulsion: mixing a water solution of polymyxin B and a dichloromethane solution of polylactic acid-glycolic acid copolymer to obtain a water-in-oil emulsion; (2) preparing an ethanol aqueous solution of hyaluronic acid; (3) mixing the water-in-oil emulsion and the ethanol aqueous solution of hyaluronic acid, and stirring to obtain a nano dispersion; (4) vacuum rotary evaporation of the nano dispersion, collection of a colloidal dispersion, and dispersion of the colloidal dispersion in water to obtain a nano particle solution.The nano preparation prepared by the application does not need a chemical crosslinking agent, and thus effectively avoids problems caused by the introduction of chemical crosslinking.The preparation process is simple and easy to control, has good safety, has good biocompatibility, and provides a basis for the approval of clinical trials and industrial development of atomization drug delivery of antibiotics.

The invention discloses an antibacterial peptide, a pharmaceutical composition and application, and belongs to the field of polypeptide medicines.The antibacterial peptide forms a novel annular conformation by introducing n-leucine and 2-aminobutyric acid to construct a parent nucleus structure. The affinity of the antibacterial peptide to the main component phosphatidylglycerol of a bacterial cell membrane is remarkably improved, is improved by 31 times or more compared with polymyxin B and is improved by 16 times or more compared with D50 peptide, and the selectivity of the antibacterial peptide to the main component phosphatidylcholine of a mammalian cell membrane is improved by hundreds of times or more compared with that of a control peptide. The polymyxin B peptide has extremely low toxicity to HK-2 kidney cells, and the biological safety of the polymyxin B peptide is obviously superior to that of polymyxin B and D50 peptide. The minimum inhibitory concentration of the antibacterial peptide to gram-negative bacteria is as low as 0.03 mu g / mL, is about 33 times higher than that of polymyxin B, and is 17-33 times higher than that of D50 peptide. The treatment effect of the antibacterial peptide is obviously superior to that of polymyxin B and D50 peptide in various infection models, and the antibacterial peptide is expected to be developed into a novel anti-infection drug and is used for preventing and treating various infections.

The invention provides an endotoxin adsorbent and a preparation method thereof. The preparation method comprises the following steps: S1, preparing epoxidized styrene-divinyl benzene resin; s2, dispersing the epoxidized styrene-divinyl benzene resin obtained in the step S1 into an organic solvent, wherein the epoxidized styrene-divinyl benzene resin with carboxyl obtained by reaction still contains an epoxy group; s3, mixing and reacting the epoxidized styrene-divinyl benzene resin with carboxyl obtained in the step S2 with a reaction solution containing an amination reagent to obtain styrene-divinyl benzene resin with both amido and carboxyl; s4, the styrene-divinyl benzene resin with the amido and carboxyl obtained in the step S3 reacts with polymyxin B under the action of a condensing agent, and the endotoxin adsorbent is obtained. The endotoxin adsorbent prepared by the method is excellent in adsorption performance, strong in specificity, high in mechanical strength, good in biocompatibility and not easy to fall off.

The present application belongs to the technical field of antibacterial medicine, and particularly relates to a benzene sulfonyl indole structure modified ruthenium polypyridyl complex with the function of inhibiting bacterial toxin as well as a preparation method and application thereof. The benzene sulfonyl indole structure modified ruthenium polypyridyl complex has the following structure: The benzene sulfonyl indole structure modified ruthenium polypyridyl complex not only has excellent antibacterial ability, but also does not induce bacterial drug resistance. The benzene sulfonyl indole structure modified ruthenium polypyridyl complex can be used in combination with polymyxin B to achieve better antibacterial effect. In addition, it is found that the benzene sulfonyl indole structure modified ruthenium polypyridyl complex has certain antibiofilm effect, and the mechanism thereof is further studied. The complex can also effectively inhibit the hemolysis phenomenon caused by bacteria and has concentration dependence.

The application discloses a group of low-toxicity broad-spectrum antibacterial peptides containing a central PXXP hinge structure and application thereof. The low-toxicity broad-spectrum antibacterial peptides are obtained by using a head design method, using positively charged lysine (Lys, K) and hydrophobic tryptophan (Trp, W), symmetrically arranging the two kinds of amino acids alternately and repeatedly, and introducing a PXXP hinge structure containing proline into the symmetry center of the antibacterial peptide sequence. The structural general formula is (KW) n PXXP(WK) n wherein XX=KK, n=2-4 or XX=WK, n=2-3. In-vitro antibacterial experiments show that the antibacterial peptides have broad-spectrum antibacterial activity; the preferred antibacterial peptides have the advantages of low hemolytic toxicity and high serum stability. Induced drug resistance experiments show that the preferred antibacterial peptides have the characteristics of low drug resistance occurrence. In-vivo acute toxicity experiment results show that, compared with a control drug Polymyxin B, the preferred antibacterial peptides have higher in-vivo safety. Therefore, the antibacterial peptides have good application prospects in the preparation of clinical antibacterial drugs and are expected to become new antibiotic candidate drugs.

The invention relates to a multifunctional bacterial cellulose gel film and a preparation method and application thereof.The gel film is synthesized by acetobacter xylinum in situ in a fermentation medium containing polymyxin B and panax notoginseng saponins, the gel film is of a three-dimensional network structure, the polymyxin B and the panax notoginseng saponins are wrapped in a bacterial cellulose network, and the polymyxin B and the panax notoginseng saponins are evenly distributed in the bacterial cellulose network. And the fiber diameter of the gel film is 48.68 + / -5 nm. The prepared wound dressing has the wet adhesion characteristic and can effectively promote rapid and scar-free healing of chronic infectious wounds and large-area wounds, so that the method is expected to be widely applied to green synthesis of the wound dressing with antibacterial and wound healing promoting functions, and a new form is provided for use of the pseudo-ginseng powder and the polymyxin B.

The invention relates to the technical field of microbiological detection, in particular to a method for detecting clostridium in cosmetics. The invention provides a modified reinforced clostridium culture medium, a modified Columbia agar culture medium and a method for detecting clostridium in cosmetics, and the method is specifically as follows: the modified reinforced clostridium culture medium can inhibit the activity of preservatives in the cosmetics and improve the clostridium detection rate by adding Tween 80, lecithin and sodium thiosulfate; according to the modified Columbia agar culture medium, polymyxin B and gentamicin in a specific proportion are added, so that interference of non-target bacteria can be effectively inhibited, and detection specificity is enhanced. Based on the two modified culture media, the detection method established by the invention adopts a sample preparation mode of normal temperature and heating dual-condition treatment, and the detection rate of target bacteria can be remarkably improved. The method has the advantages of rapidness, high efficiency, high specificity, high detection rate, low cost, simplicity and convenience in operation and the like, and is particularly suitable for rapid screening requirements of supervision departments and detection mechanisms.

The invention provides an application of Ginsenoside C-K in preparation of a medicine for resisting gram bacterial infection, and the CAS number of the Ginsenoside C-K is 39262-14-1, the CAS number of the Ginsenoside C-K is 39262-14-1, and the CAS number of the Ginsenoside C-K is 39262-14-1. The Ginsenoside C-K is used for preparing a medicine for resisting gram-positive bacterium infection, and the Ginsenoside C-K and a polypeptide antibiotic polymyxin B are combined to be used for preparing a medicine for resisting gram-negative bacterium infection. According to the technical scheme, the novel medical application of the Ginsenoside C-K. The Ginsenoside C-K has the effects of inhibiting growth of gram-positive bacteria and formation of a biofilm, and the Ginsenoside C-K and polypeptide antibiotic polymyxin B are combined to have the effect of reversing drug resistance of gram-negative bacteria to the polymyxin B. The invention further discloses a preparation method of the Ginsenoside C-K.

The invention relates to the technical field of microbial pharmacy, in particular to a method for improving the fermentation level of polymyxin B by using active peptide BHL. The method comprises the following steps: activating polymyxin B producing bacteria, picking and inoculating the polymyxin B producing bacteria into a seed culture medium containing active peptide BHL, and then placing the seed culture medium in a constant-temperature shake-flask incubator at 27-31 DEG C and 220 rpm for shake culture for 20-24 hours to obtain a seed solution; transferring the seed solution into a fermentation culture medium containing active peptide BHL, and then placing the fermentation culture medium in a constant-temperature shake-flask incubator at 27-31 DEG C and 220 rpm for shaking fermentation culture for 20-65 hours to obtain a fermentation solution; and adjusting the pH value of the fermentation liquor to 1.8-2.5 by using oxalic acid, and then detecting the titer of the polymyxin B.

The invention belongs to the technical field of biology, and particularly relates to a bifidobacterium longum subsp. Longum FMBL B241768LS, a microbial inoculum and application of the microbial inoculum in hypoglycemic products, the bifidobacterium longum subsp. Longum FMBL B241768LS is preserved in China Center for Type Culture Collection on October 14, 2024, and the preservation number is CCTCC NO: M 20242173; the inhibitory activity of the compound on dipeptidyl peptidase IV is as high as 79.17%; the compound has a relatively good inhibition effect on the activity of alpha-glucosidase and alpha-amylase; the compound shows drug resistance to ciprofloxacin, ampicillin, penicillin G, clindamycin, kanamycin and polymyxin B; a good inhibition effect is achieved on pathogenic bacteria; the strain can be used for preparing medicines, fermented foods, health-care products and food additives for reducing blood sugar and inhibiting pathogenic bacteria, and has a wide application prospect.

The invention belongs to the technical field of biological medicines, and discloses a cyclized antibacterial peptide CycP-1 targeting multiple drug-resistant klebsiella pneumoniae, and a composition and application thereof. The amino acid sequence of the antibacterial peptide is shown as SEQ ID NO.1, cysteine residues at the first site and the 24th site in a molecule of the antibacterial peptide form a disulfide bond, and the antibacterial peptide is in cyclization conformation and shows good in-vitro protease stability. Experiments show that the antibacterial peptide has a remarkable inhibiting effect on multi-drug-resistant and pan-drug-resistant klebsiella pneumoniae, and when the antibacterial peptide is combined with antibiotics, the antibacterial effect can be enhanced, drug resistance can be reversed or reduced, and generation of drug resistance can be delayed. A mouse pneumonia model in-vivo experiment further proves that after oral administration of the antibacterial peptide, the lung tissue bacterial load of a pan-drug resistant klebsiella pneumonia infected mouse can be remarkably reduced, lung pathological injury is relieved, the survival rate of the infected mouse is remarkably increased, and the effect is better when the antibacterial peptide is combined with polymyxin B.

This invention relates to the field of biochemical technology, and particularly to highly specific haptens of polymyxin B and colistin, artificial antigens, their preparation methods, and applications. The haptens have structures as shown in Formula I or Formula II. The applications include: (1) preparing specific antibodies against polymyxin B or colistin; (2) detecting specific antibodies against polymyxin B or colistin; and (3) preparing reagents for detecting specific antibodies against polymyxin B or colistin. This invention further provides artificial antigens obtained by conjugating the haptens with carrier proteins. Using the artificial antigens provided by this invention as immunogens to immunize experimental animals, highly specific and sensitive antiserum can be prepared, which can then be used to extract and prepare polyclonal antibodies. These methods can be used to establish highly specific, highly sensitive, simple, and rapid detection methods for polymyxin B and colistin, and have significant application value.

The present invention discloses the use of dehydroandrographolide in synergistic effect with polymyxin B in the preparation of a drug for treating Gram-negative bacterial infections. The Gram-negative bacteria include Escherichia coli, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Salmonella. The present invention also discloses an antibacterial combination ratio of dehydroandrographolide and the antibiotic polymyxin B, as well as an optimal ratio for treating animal infections. This invention provides a new therapeutic strategy for the clinical treatment of bacterial infectious diseases.

The invention discloses an antibacterial peptide, a pharmaceutical composition and application, and belongs to the field of polypeptide medicines.The antibacterial peptide forms a novel annular conformation by introducing n-leucine and 2-aminobutyric acid to construct a parent nucleus structure. The affinity of the antibacterial peptide to the main component phosphatidylglycerol of a bacterial cell membrane is remarkably improved, is improved by 31 times or more compared with polymyxin B and is improved by 16 times or more compared with D50 peptide, and the selectivity of the antibacterial peptide to the main component phosphatidylcholine of a mammalian cell membrane is improved by hundreds of times or more compared with that of a control peptide. The polymyxin B peptide has extremely low toxicity to HK-2 kidney cells, and the biological safety of the polymyxin B peptide is obviously superior to that of polymyxin B and D50 peptide. The minimum inhibitory concentration of the antibacterial peptide to gram-negative bacteria is as low as 0.03 mu g / mL, is about 33 times higher than that of polymyxin B, and is 17-33 times higher than that of D50 peptide. The treatment effect of the antibacterial peptide is obviously superior to that of polymyxin B and D50 peptide in various infection models, and the antibacterial peptide is expected to be developed into a novel anti-infection drug and is used for preventing and treating various infections.

The present invention relates to a pharmaceutical product in the form of a storage stable lyophilisate or a pharmaceutical formulation in the form of a sterile solution for parenteral administration. Both the lyophilisate and solution consist essentially of a polymyxin selected from polymyxin E, polymyxin B, or a pharmaceutically acceptable derivative thereof, and zidovudine or a pharmaceutically acceptable derivative thereof. The solution further includes an aqueous carrier.

The present application relates to a kind of bacteriophage lytic enzyme LysSPYS2, containing bacteriophage lytic enzyme composition and its application, bacteriophage lytic enzyme LysSPYS2 sequence is as shown in SEQ ID No.1, the bacteriophage lytic enzyme has high-efficiency, broad-spectrum bactericidal effect;It has lytic effect to a variety of bacteria, can be used as bacteriostatic agent;Further, the bacteriophage lytic enzyme is combined with polymyxin B, can exert synergistic antibacterial effect, significantly reduce the amount of antibiotic;The bacteriophage lytic enzyme can also be used with Magnolol, realize outstanding bacteriostatic effect.

The application belongs to the technical field of nano probes, and particularly relates to a nano probe and a preparation method and application thereof. The nano probe comprises magnetic nano materials and long afterglow nano materials. The magnetic nano materials comprise magnetic nano particles modified with concanavalin A, and are used for recognizing, capturing and separating bacteria. The long afterglow nano materials comprise green long afterglow nano particles modified with polymyxin B and red long afterglow nano particles modified with vancomycin. The green long afterglow nano particles modified with polymyxin B and the red long afterglow nano particles modified with vancomycin are respectively used for recognizing and outputting anti-interference signals. The nano probe can be applied to identifying gram-negative and gram-positive bacteria, can improve the anti-interference capability of detection, and has the advantages of rapidness, simplicity, low cost and high stability.

The present invention discloses an antimicrobial peptide, a pharmaceutical composition, and an application thereof, belonging to the field of polypeptide medicine. The antimicrobial peptide constructs a core structure by introducing norleucine and 2-aminobutyric acid to form a novel cyclic conformation. The antimicrobial peptide has a significantly improved affinity for phosphatidylglycerol, the main component of bacterial cell membranes, which is more than 31 times higher than polymyxin B and more than 16 times higher than D50 peptide. The selectivity for phosphatidylcholine, the main component of mammalian cell membranes, is more than 100 times higher than the control peptide. It has extremely low toxicity to HK-2 kidney cells and its biosafety is significantly better than that of polymyxin B and D50 peptide. The minimum inhibitory concentration of the antimicrobial peptide against Gram-negative bacteria is as low as 0.03 μg / mL, which is about 33 times higher than polymyxin B and 17-33 times higher than D50 peptide. The therapeutic effect of the antimicrobial peptide is significantly better than that of polymyxin B and D50 peptide in multiple infection models, and it is expected to be developed into a new anti-infective drug for the prevention and treatment of various infections.

This invention relates to a phage lysin LysSPYS1, a composition containing the phage lysin, and their applications. The sequence of the phage lysin LysSPYS1 is shown in SEQ ID No. 1. This phage lysin exhibits highly efficient and broad-spectrum bactericidal activity; it has a lytic effect on a variety of bacteria and can be used as a bacteriostatic agent. Furthermore, combining this phage lysin with polymyxin B can exert a synergistic antibacterial effect, significantly reducing the amount of antibiotics used. The phage lysin can also be used in combination with magnolol to achieve a prominent antibacterial effect.

The invention discloses a polymyxin B modified cellulose-based liquid dressing as well as a preparation method and application thereof. According to the liquid dressing, polymyxin B modified cellulose particles are combined with a polyvinyl alcohol glycerol film forming system; a wet healing environment and a physical barrier are used for promoting wound regeneration, gram-negative bacterium infection is eliminated based on hydrogen-bond interaction and electrostatic interaction, strong bactericidal ability is achieved, and the killing rate of gram-negative bacteria under the minimum inhibitory concentration is larger than 99.9%. Besides, the liquid dressing has good viscosity and film-forming property, can form a film after being smeared on a wound for 3 minutes, and meets the requirements of protecting the wound and providing a suitable environment for promoting wound healing; and meanwhile, the device is easy to remove and does not damage new tissues. The problem of systemic toxicity exposure caused by application of polymyxin B to large-area wounds is solved, and an innovative solution is provided for solving wound infection and promoting wound healing.

The invention discloses a deuterated antibacterial peptide as well as a composition and application thereof, and belongs to the field of biological medicines. By introducing deuterated 2-aminobutyric acid to form an annular structure and combining deuterated modification, the affinity of the antibacterial peptide to a bacterial membrane is greatly improved compared with that of traditional drugs (polymyxin B and D50), and the selectivity of the antibacterial peptide to a mammalian membrane is 884 times or above higher than that of a control; the minimum inhibitory concentration to gram-negative bacteria in vitro is as low as 0.015 mu g / mL, which is increased by 67 times compared with polymyxin B, is increased by 33-67 times compared with D50 control peptide, and is increased by about 17 times compared with non-deuterated antibacterial peptide 5, so that extremely-low-concentration efficient bacteriostasis is realized; the toxicity to human kidney cells is extremely low, and the biological safety is better. In a plurality of infection models, the treatment effect of the compound is obviously better than that of the three control substances, and the compound can be used for preparing anti-infection drugs, provides a new scheme of high efficiency and low toxicity for clinical anti-infection treatment, and is suitable for prevention and treatment of a plurality of infections.

The invention relates to the technical field of pharmaceutical compositions, in particular to a pharmaceutical composition for synergistically inhibiting klebsiella pneumoniae and infectious pneumonia of the klebsiella pneumoniae, a preparation and application, and the composition is prepared from the following components in parts by weight: 50-200 parts of berberine, 10-100 parts of andrographolide, 10-100 parts of manuka honey and 10-50 parts of polymyxin B. In-vitro antibacterial study is carried out on the berberine, the andrographolide, the manuka honey and the polymyxin B, and it is found that the andrographolide, the berberine and the manuka honey can all improve the antibacterial effect of the polymyxin B and all generate a synergistic effect when being combined for use; besides, the combination of the four medicines provided by the invention is used for treating a mouse suffering from Klebsiella pneumonia infectious severe pneumonia, the effect of the combination of the four medicines is obviously superior to that of a single medicine, and the effect of treating the Klebsiella pneumonia infectious severe pneumonia can be obviously improved after the medicine composition provided by the invention is compounded.