33 results about "Polypeptide antibiotic" patented technology

The invention discloses a synergist for improving the gram-positive-bacterium-resistant effect of nisin. Microdilution method drug susceptibility tests and chessboard type microdilution tests are used, tested bacteria comprise nine staphylococcus aureus food isolated strains, nine listeria monocytogenes food isolated strains and two quality-control strains for contrast, that is, staphylococcus aureus ATCC 29213 and listeria monocytogenes ATCC 19115, the effect caused by perilla oil on the antibacterial activity of the nisin is measured, and test results prove that the perilla oil has the effect of enhancing the gram-positive-bacterium-resistant activity of the nisin. The nisin is a polypeptide antibiotic substance extracted from a streptococcus lactis fermentation product, can be degraded by some proteases in human body digestive tracts easily, and has no adverse effect on colors, aromas, tastes and the like of food, and perilla is rich in alpha-linolenic acid and has effects of resisting oxidation, resisting ageing, resisting thrombus, preventing and treating cardiovascular diseases, resisting cancers, resisting allergies and resisting inflammations. High-nisin and the perilla oil are used as food preservatives, the additive amount of the high-nisin can be decreased, safe and reliable purposes can be achieved, and the health-care effect can be realized.

The invention relates to a method for producing polypeptide antibiotics enramycin by the fermentation method, which pertains to the fields of agricultural biotechnology, industrial biotechnology and the fermentation engineering. The method is as follows: (1) slant culture: a Streptomyces sp.NJWGY3665 bacterial strain is inoculated in a glucose nutrient culture medium to carry out the slant culture, the culture temperature is 28 to 37 DEG C and the culture time is 2 to 6 days; (2) seed culture: a spore which is cultured on a slant is produced into a single-spore suspension by using sterile water, which is also inoculated in a seed culture medium for culture, the temperature is 28 to 32 DEG C, the rotational speed is 200rpm and the culture lasts for 2 to 6 days; (3) fermentation culture: the seed liquid is inoculated in a fermentation culture medium for culture, the temperature is controlled at 28 to 37 DEG C, the pH is controlled at 6.0 to 9.0, the rotational speed is 180 to 220rpm, the fermentation lasts for 5 to 9 days, so as to obtain the Streptomyces sp., methanol or ethanol is used for the extraction and separation of mycelium through the method of centrifugal separation, then the resin method is adopted for carrying out refining, so as to obtain the peptide antibiotics enramycin.

The invention relates to a method for improving the antibacterial properties and stability of cationic short peptides, belonging to the technical field of antibacterial drugs. The method mainly includes the use of negatively charged polyanions to induce the assembly of cationic short peptides to form water-soluble cationic polymers, thereby enhancing the bonding ability between cationic short peptides and bacterial cell membranes, and effectively avoiding the traditional cationic short peptides on the surface of bacterial cell membranes. Migration, aggregation and other deficiencies ultimately greatly improve the antibacterial properties and stability of cationic short peptides. The advantage of this method lies in the purpose of improving the antibacterial properties and stability of cationic short peptides through simple and convenient steps. In addition, this method breaks through the limitations of traditional antimicrobial peptides such as long sequences, complex synthesis, high price, difficulty in batch synthesis, and poor stability, and greatly expands the range of antimicrobial peptides. It is expected to be used in the development, screening and application of peptide antibacterial drugs. play an important role.

The invention discloses a plypeptide antibiotic device, including a device man body and a function switching cavity provided in the device main body, wherein a function switching device is arranged inthe function switching cavity; the function switching device includes a switching button capable of moving up and down in the function switching cavity. The plypeptide antibiotic device of the invention has the advantages of simple structure and convenient operation. Through the device, rapid grinding of plant materials are achieved, damage to medical ingredients caused by high temperature and high pressure during traditional medicine grinding production is avoided, extraction efficiency and extraction effect of polypeptide antibiotics later are greatly improved. At the same time, an automatic discharging device is provided, residues and slag can be automatically discharged with one click, no manual power to clean residues and slag is needed, medicine preparation efficiency is greatly improved and the polypeptide antibiotic device is worth recommending and using.

The invention provides a polypeptide antibiotic and its preparation method and application. The polypeptide antibiotic comprises an antibacterial peptide and a nitric oxide donor, and the antibacterial peptide is connected with the nitric oxide donor. The polypeptide antibiotic of the present invention connects the antibacterial peptide and the nitric oxide donor, disperses the biofilm through the cooperation of the antibacterial peptide with the nitric oxide, enhances the bactericidal effect, effectively kills the bacteria forming the biofilm, and is widely used.

The invention discloses a method for biosynthesizing virginiamycin by streptomycete, which comprises the following steps of: preparing a slope with spores of virginiamycin; inoculating the slope spores into a culture medium to obtain a seed solution; inoculating the seed solution into a fermentation culture medium for fermentation culture, adding a precursor substance at the early stage of fermentation so as to increase the yield of virginiamycin; and further processing the fermentation solution after fermentation to obtain virginiamycin crystals. The method disclosed by the invention is simple and easy to implement, is stable in the fermentation result and low in production cost. The fermentation result is improved compared with the traditional process, and the highest yield of virginiamycin can reach 3500 mu g / ml. Virginiamycin is polypeptide antibiotic containing lactonic rings, has the characteristics of no toxicity, no accumulation, easiness in degradation, and no drug resistance, and is a new animal feed additive.

The invention relates to a pulse-type administration preparation of anti-drug-resistant-bacteria antibiotic microsphere, wherein the preparation comprises three parts capable of achieving pulse slow release in three times. The three parts include: a quick release part, which contains a main drug core microsphere; an N-hour delaying part, which contains a main drug core microsphere, an inner-layermixture coating, and an outer-layer enteric polymer coating; and a 2N-hour delaying part, which contains a main drug core microsphere, an inner-layer mixture coating, and an outer-layer enteric polymer coating, wherein N is a natural number in a range of 2-6. The main drug is anti-drug-resistant-bacteria antibiotics, which includes carbapenem antibiotics, aminoglycoside antibiotics, and polypeptide antibiotics. The preparation has a pulse-type administration system that ensures conveying of a single medicine or a medicine association at the same time and a controller of pulse-type administration time for efficiently treating diseases, and has maximum patient compliance and minimum side effect.

The invention belongs to the technical field of medicine synthesis, and discloses a method of pure-solid-phase synthesis of polypeptide antibiotic Colistin. By use of the method, the synthetic process and procedure of the Colistin are simplified, the synthesis time is shortened, and the use amount of solvents is reduced.

The invention discloses a method for producing polypeptide antibiotics nosiheptide through fermentation. The method comprises the following steps of: inoculating streptomyces actuosus to a slant culture medium for carrying out slant culture; inoculating an obtained slant with spores to a seed bottle to culture a seed solution; inoculating the seed solution to a fermentation culture medium for carrying out fermentation culture according to an inoculation quantity of 10 wt%; and further treating the fermented fermentation liquor to obtain nosiheptide crystals. The nosiheptide is produced by adopting a fermentation method. The method is simple and easy and is low in production cost. The polypeptide antibiotics nosiheptide produced by adopting the method can be used as a safe, high-efficiency and environmental-friendly novel feed additive.