293 results about "Polymyxin" patented technology

The invention relates to a compound microbial agent for degrading antibiotic and pesticide residues as well as preparation and application thereof, and belongs to the field of biotechnology and environmental protection. Multi-thallus compound microbial powder is prepared from the compound microbial agent according to the weight percentage of living microbes to the total amount of compound microbial powder as follows: 10%-15% of bacillus subtilis, 10%-15% of aspergillus niger, 10%-15% of bacillus mucilaginosus, 10%-15% of enterococcus faecalis, 8%-12% of bacillus licheniformis, 8%-12% of bacillus megaterium, 8%-12% of pseudomonas fluorescens, 5%-8% of lactobacillus plantarum, 5%-8% of bacillus polymyxin and 6%-8% of streptococcus thermophiles. The compound microbial agent has the effects of degrading antibiotic and pesticide residues, fermenting and composting organic matter, acting as functional fertilizer and repairing the environment, and can solve the problems of secondary pollution caused by antibiotic residues in culture feces and resource utilization of organic waste and realizes biodegradation of the antibiotic and pesticide residues in soil when applied to the agricultural ecological environment, thereby being of great value and practical significance in restoration of agricultural ecological environment and protection of human health.

Novel protected cyclopeptide intermediates are prepared from polymyxin B are used to synthesize new peptide antibiotics. Intermediates are readily derivatized and deprotected to provide new families of antibiotics, which have potent anti-bacterial activity against gram-negative bacteria; but also are useful and potent against gram-positive bacteria.

The present invention provides a new class of polymyxin derivates useful for treating bacterial infections, especially Gram-negative infections, that have reduced renal cytotoxicity.

The invention relates to the fields of analytical chemistry and food safety, particular to a method for detecting the residual quantity of multiple polypeptide veterinary drugs in animal-derived foods. The method comprises the following steps of: processing a sample with a TCA(trichloroacetic acid) and acetonitrile system for depositing proteins; extracting with a carbinol and 0.1% formic acid aqueous solution system; purifying with a Oasis HLB solid phase extraction column; performing gradient elution with an Eclipse XDB-C18 analytical column in the presence of an acetonitrile and 0.1% formic acid aqueous solution used as a mobile phase; and then performing electrospray and positive ion scanning mode separation for finally detecting four polypeptides. The limits of the four polypeptides, namely colistin, bacitracin A, polymyxin B and virginiamycin M, are 25 micrograms/kilogram, 100 micrograms/kilogram, 250 micrograms/kilogram and 120 micrograms/kilogram respectively; the recovery rates of colistin, bacitracin A, polymyxin B and virginiamycin M are 74.9-88.1%, 76.2-89.0%, 76.6-81.2% and 77.3-86.9% respectively; and the coefficients of variation (CV%) of colistin, bacitracin A, polymyxin B and virginiamycin M are 5.7-15.1%, 7.2-15.7%, 6.0-8.0% and 9.5-18.6% respectively. The detection limit, the recovery rate, the accuracy and other technical indexes all meet related detection requirements at home and aboard.

An endotoxic adsorpting method for treating endotoxemia and anaphylactic reaction caused by endotoxemia is prepared through activating the hydroxy group of agarose gel or DVA as carrier by cyanogen bromide or epoxy chloropropane or sulfuryl chloride, and adding polymyxin solution.

The invention provides a method for separately preparing for polymyxin E, which uses foam separation method to extract and separate the polymyxin E from fermentation liquor. The fermentation liquor obtains polymyxin E raw medicine by first treatment, form separating, vacuum evaporation and spray drying.

The invention discloses a fluorescent PCR detection method for drug resistance gene mcr (mobile colistin resistance)-4/5/8. A protection primer combination provided by the invention consists of single-stranded DNA represented by sequence 1 to sequence 6 in the sequence table. The SYBR dye-based fluorescent quantitative PCR method for the three mcr genes is established. The detection method has thetechnical advantages of high speed, high sensitivity and strong specificity, and is suitable for monitoring the prevalence of polymyxin drug resistance gene mcr-4/5/8 in clinical and animal husbandry.

The combination of a polymyxin composition and a hop composition produces unexpected and synergistic activity against gram positive bacteria.

The invention discloses a process for extracting colistin sulfate through a precipitation method. The process comprises the following steps of: (a) adjusting pH of fermentation liquor containing polymyxin E with oxalic acid or concentrated sulfuric acid, and filtering with a filtering device; (b) adding 0 metal complexing agent and inorganic flocculant to the filtrate, and reacting at normal temperature for 0.5 to 4.0h; (c) heating, cooling, and vacuum-filtering the reactive liquid; (d) adjusting pH of the filtrate above with aqueous alkali, separating the solid from the liquid to obtain a filter cake, dissolving the filter cake with sulfuric acid solution so as to obtain acidizing fluid, adding potassium permanganate and activated carbon to the acidizing fluid respectively, agitating for0.5 to 2.0 hours, and then vacuum-filtering to obtain colistin sulfate liquid; and (e) centrifugally spray-drying the colistin sulfate liquid. With the adoption of the process, the common problems ofthe existing process for purifying fermentation liquor that the steps are complicated, the period is long, the labor intensity is relatively high, and the wastewater is difficult to treat and the like can be overcame.

The invention discloses a broad-spectrum biological bactericidal air filtration material and a preparation method thereof. The invention is not only applicable to the general families and business departments with the need of air purification, but is also applicable to the semiconductor, pharmaceutical, hospitals and other environments with higher requirements of cleanliness. The broad-spectrum biological bactericidal air filtration material of the invention comprises at least one biological anti-bacterial agent and glass fiber filter paper, and the biological anti-bacterial agent is lysozyme, protamine sulfate, poly-lysine, nisin, polymyxin sulfate, glycine or natamycin. The preparation method of the invention is that the air filtration material is prepared by silanization, hydroformylation, condensation reaction and removal of the physically absorbed anti-bacterial agent. The biological bactericidal air filtration material prepared by the invention has low consumption of the anti-bacterial agent and no influence on the resistance of the filtration material; the sterilization rate is high, most of the killing rate of bacterial, spores and viruses is more than 99 percent, and the fungal growth is inhibited.

The invention provides multiple PCR primers for detecting polymyxin drug resistance genes. The multiplex PCR primers are composed of the following five primer pairs, including the primer pair shown inSEQ ID No:1 and SEQ ID No:2, the primer pair shown in SEQ ID No:3 and SEQ ID No:4, the primer pair shown in SEQ ID No:5 and SEQ ID No:6, the primer pair shown in SEQ ID No:7 and SEQ ID No:8 and the primer pair shown in SEQ ID No:9 and SEQ ID No:10. The invention further provides a detection kit and a detection method for detecting the polymyxin drug resistance genes. The primers are designed based on a gene sequence of mcr-1, mcr-2, mcr-3, mcr-4 and mcr-5, and the drug resistance genes corresponding to the sizes of different PCR products are distinguished. After a reaction system and conditions are optimized, finally, a complete multi-PCR reaction system is determined. The quick and effective detection method is provided for simultaneously detecting the polymyxin drug resistance genes-a mcr gene family and has high sensitivity and specificity.

The present invention relates to color developing culture medium, detecting kit and detection method for Vibrio parahaemolyticus, and belongs to the field of food microbe safety monitoring technology. The detecting kit consists of color developing culture medium comprising bacterial specific enzyme in 0.05-0.95 g and mixed color developing substrate Y-glucoside, enrichment liquid A of pancreatic casitone liquid culture medium and enrichment liquid B comprising sodium chloride, polymyxin and broth. The detection method includes the enrichment culture of the sample in enrichment liquid A and enrichment liquid B, the culture of the two parts of enrichment cultured liquid in the color developing culture medium, and judging whether to exist Vibrio parahaemolyticus according to whether to have smooth raised purple colony of 2-3 mm diameter. The present invention has low cost, high detection sensitivity, short detection period and other advantages.

The invention discloses a microbial feed additive for treating piglet yellow and white dysentery and a preparation method thereof. The additive is prepared from the main components of bacillus subtilis and saccharomyces cerevisiae which are mixed with baking soda, xylo-oligosaccharides, vitamins, vitamin complex, glucose and the like according to certain proportions. The microbial feed additive has the following advantages that: the active substances such as subtilin, polymyxin, nystatin, gramicidin and the like generated in the growing process of the bacillus subtilis have obvious inhibitionto pathogens or conditioned pathogens of endogenous infection; cell wall polysaccharides of the saccharomyces cerevisiae and a great amount of nucleotides and bioactive peptides generated in the growing process of the saccharomyces cerevisiae can improve the immunity of animals, and a compound taste substance is also generated in the growing process of the saccharomyces cerevisiae to promote animal feeding; the baking soda replenishes electrolyte; the xylo-oligosaccharides selectively proliferate beneficial bacteria such as bifidobacterium and the like; the vitamins have the effects of resisting stress and replenishing nutrition; and the glucose has the effects of supplying energy and promoting healing.

The invention discloses a gene fragment which has a nucleotide sequence as shown in SEQ ID NO.1; the invention also provides a vector pPlasmid-Clearance, wherein the vector pPlasmid-Clearance is constructed by inserting the gene fragment having the nucleotide sequence as shown in SEQ ID NO.1 into a resistance gene region of a conjugal transfer vector pEF01 through a homologous recombination method; the conjugal transfer vector pEF01 has the nucleotide sequence as shown in SEQ ID NO.2. The gene fragment and the vector pPlasmid-Clearance can reverse the drug resistance of drug resistant bacteria of polymyxin drug-resistant gene mcr-1 in bacterial flora of environments and animals, can block the spread of polymyxin drug-resistant gene mcr-1, and have great application potential in the prevention and clinical treatment of bacterial diseases.

The invention provides a composite hydrogel wound dressing and a preparation method thereof. The aminated collagen and oxidized sodium alginate are used as base materials; two polypeptide antibiotics,namely polymyxin B sulfate and bacitracin are loaded; and the AC/OSA-PB composite hydrogel dressing is prepared through a Schiff base reaction. The preparation method is simple to operate; the requirements on reaction conditions are low; gel can be formed in a short time, large-scale production is facilitated, and the prepared wound dressing not only has a good bactericidal effect, but also can improve the HSF cell mobility and the HSF cell proliferation rate to the maximum extent, has excellent wound healing promoting capacity, and also has mechanical properties and mechanical properties suitable for skin wounds.

The invention relates to genitourinary tract microorganism cultivation and detect method thereof, in particular to a genitourinary tract ureaplasma urealyticum (Uu) and mycoplasma hominis (Mh) culture medium and a detect method thereof. The culture medium comprises a fluid medium and a solid medium which are combined when the medium is used for culturing, separating and differentiating mycoplasma. The formulation comprises essential elements such as tryptic soy broth, yeast extract, urea, arginine, L-cysteine, phenol red, HEPES liquid, calf (fetal calf) serum, manganese sulfate, vancomycin, amphotericin B, trimethoprim, polymyxin, penicillin, and the like, and thereby the nutrition for mycoplasma growth and the antibiotic combination for inhibiting undesired microbe growth are optimized, no millipore filter is needed for sample inoculation and subcultivation, and the mycoplasma grows quickly. The fluid medium can maintain and prolong the logarithmic phase and indicate the growth of the mycoplasma, and the solid medium can used for observing Uu and Mh bacterial colonies, which has large background reflectance, thereby being easy for differentiation and significantly increasing the sensibility and the specificity of genitourinary tract mycoplasma detect.

The invention provides a method for producing polymyxin E through fermentation and foam separation coupling. According to the method, polymyxin E is prepared by a circulating reflux device formed by a peristaltic pump through fermentation, film separation and foam separation coupling. During coupling operation, fermentation liquor enters a foam separation tower through a film filter by means of the peristaltic pump, products and a liquid pass through the film while cells are intercepted in a fermentation tank, fermentation continues to be performed, and constancy of bacteria is guaranteed; a foam distributor is mounted at the bottom of the foam separation tower, bubbles are produced through air blowing, foam separation is performed, part of nutrients enter the foam separation tower through the film filter, a remaining liquid produced after foam separation returns to the fermentation tank in a circulating reflux manner, and sufficient utilization of the nutrients is guaranteed; coupling outside a tank body is adopted, operation conditions for fermentation and operation conditions for foam separation are controlled respectively, and the best operation conditions can be met.

The invention discloses an antibacterial drug composition for treating Gram-negative bacterial infections. The composition is prepared from TNP-2092 and a cell membrane penetrant, wherein the cell membrane penetrant is polymyxin B or polymyxin E. According to the antibacterial drug composition for treating Gram-negative bacterial infections, the Gram-negative bacterial infections are treated through the combined use of TNP-2092 and the cell membrane penetrant, the antibacterial activity of the composition is enhanced compared with the use of TNP-2092 or the cell membrane penetrant alone, and the composition has an antibacterial synergistic effect and can be used for treating the Gram-negative bacterial infections, including drug-resistance bacterial infections.

The invention provides an arenicola cristata antibacterial peptide NZ17074 derived peptide N6 and application thereof. An antibacterial peptide NZ17074 molecular structure is optimally designed to obtain a novel derived peptide N6, and the amino acid sequence of the novel derived peptide N6 is shown as SEQ ID NO: 1. The antibacterial peptide N6 provided by the invention has a very good sterilization effect on Gram-negative bacteria, and is used for remarkably reducing the haemolytic activity on mouse erythrocytes and the cytotoxicity on mouse original macrophages. A mouse toxemia model test result shows that the antibacterial peptide N6 also has an endoxemia resisting effect, and can be used for remarkably improving the survival rate of mice, and the effect of the antibacterial peptide N6 is better than that of an antibiotic polymyxin. The antibacterial peptide N6 has small molecular weight and is easily artificially synthesized; the antibacterial peptide N6 is a low-molecular-weight polypeptide with extremely good application value, can be used for preparing novel antibacterial and anti-infection medicines and the like, and has a good application prospect.

The invention discloses a LAMP primer group, a kit and a detection method for rapid test of a bacterial polymyxin drug resistance gene mcr-1. The kit comprises a pair of outer primers, a pair of inner primers and a pair of loop primers. The six specific primers and a DNA polymerase with strand displacement activity are adopted for amplification of a DNA sample at 60-65 DEG C, and color changes in a reaction tube can be observed to judge whether amplification occurs or not after addition of a color developing agent. The LAMP primer group, the kit and the detection method have advantages of quickness, high efficiency, simplicity and convenience in operation, high specificity, high sensitivity, simplicity and convenience in detection, suitableness for onsite detection and the like and is suitable for popularization and application.

The invention discloses a feed additive for preventing and treating virus caused death of aquatic livestock and a preparation method thereof. The feed additive for preventing and treating virus caused death is mainly prepared from the following raw materials in parts by weight: 10-20 parts of clove, 5-15 parts of root of Chinese pulsatilla, 2-7 parts of isatis root, 2-7 parts of coptis, 2-7 parts of forsythia, 2-7 parts of indigowoad leaf, 3-5 parts of florfenicol and 4-6 parts of polymyxin. The feed additive for preventing and treating virus caused death can improve the body immunity and resistance against diseases of the aquatic livestock, reduce the infection probability of the death virus and improve the effects on preventing and treating the virus caused death. The feed additive for preventing and treating virus caused death has the advantages of convenience in administration through water, high absorptivity, wide distribution, no drug residue, no side effect and wide safety range.