RU2278675C1 - Antibacterial agent and pharmaceutical composition comprising effective amount of antibacterial agent - Google Patents

Abstract

FIELD: medicine, biotechnology.

SUBSTANCE: invention relates to preparing biologically active substances from human and animal tissues. Invention proposes an antibacterial agent from pig and cattle platelets of molecular mass 0.5-15 kDa. Agent is prepared by freezing and defrosting platelet mass at temperature (-15)-(-20)°C for 24 h, centrifugation at 1000g, filtration of supernatant through dialysis membranes 15000 and 500 and elution of component comprising peptides by acetonitrile linear gradient from Sephadex G-50. Invention provides the synergetic antibacterial effect of peptides as component of the agent.

EFFECT: improved preparing method, valuable properties of agent.

8 cl, 6 tbl, 7 ex

Description

The invention relates to medicine and biotechnology, in particular to the preparation of biologically active substances from animal and human tissues, and can be used to create and use new agents with antimicrobial activity.

The growth of infections caused by microorganisms that are resistant to many antimicrobial agents [1, 2], necessitates the expansion of the arsenal of drugs with microbicidal action [3]. Currently, synthetic and semi-synthetic antibiotics (fluoroquinolones, aminoglycosides, etc.) are mainly used as bactericidal preparations, to which resistance is quickly formed in most microorganisms [4]. In addition, these drugs have a toxic effect on organs and systems of the human and animal body [5], contribute to the development of dysbiosis, etc. [5, 6].

The purpose of the invention is the creation of a new antimicrobial agent and a pharmaceutical composition containing an effective amount of an antimicrobial agent.

It is known that cationic peptides isolated from animal and human tissues have a pronounced antimicrobial effect [7].

It is known to use antimicrobial peptides isolated from human neutrophils [8], cattle [9] and mice [10] for the treatment and prevention of infectious diseases.

It is known that, in addition to neutrophils, in the anti-infection protection of a macroorganism, platelets are of some importance, because: a) platelets adhere to pathogenic microorganisms; b) have a bactericidal, antifungal and antiprotozoal effect in vitro; c) when interacting with microorganisms in vitro, platelets release low molecular weight bactericidal proteins [11].

The use of peptides isolated from rabbit platelets and their derivatives for the treatment of infectious diseases is known [12].

It is known that human platelets contain peptides with antimicrobial activity [13, 14, 15, 16].

In addition, phospholipase A2 and lysozyme [11], which also have antimicrobial activity, were also found in platelets [17, 18].

The synergistic antimicrobial effect of peptides isolated from neutrophils is known [19].

The synergistic antimicrobial effect of platelet factor-4 and connective tissue activating peptide-3 is known [20].

It is known that the minimum molecular weight of peptides contained in platelets and having an antimicrobial effect is 0.5 kDa [13].

The following antimicrobial peptides contained in platelets are known to have maximum molecular weight: phospholipase A2 (molecular weight 13.9-14.1 kDa) [17, 21] and lysozyme (molecular weight 14.7 kDa) [21].

The authors experimentally established a synergistic antimicrobial effect of peptides isolated from human platelets.

The following experiment was conducted. A mixture of antimicrobial peptides from human platelets was prepared as follows. 50 ml of platelet mass obtained from healthy donors were resuspended in 300 ml of glacial (70%) acetic acid and incubated at -15 ° - (-20 °) C for 24 hours. After incubation, the platelet suspension was thawed and centrifuged at 1000 g for 30 minutes at room temperature. The resulting supernatants were subsequently filtered through Spectra / Por Biotech Regenerated Cellulose Dialysis Membrane MWCO 15000 dialysis membranes (retention products with a molecular weight of over 15,000 daltons) and Spectra / Por Biotech Cellulose Ester MWCO 500 (passing products and salts with a molecular weight of less than 500 daltons). The ultrafiltrate concentrate was applied to a 10 × 250 mm column with Sephadex G-50. Elution was carried out by a linear gradient of acetonitrile (from 0% to 60%) with the addition of a 0.1% solution of triphosphoric acid. The obtained peptide fractions were collected, combined, the total protein content was determined by the known method [22], which was 500 μg / ml, and lyophilized. As comparison preparations, lysozyme (Calbiochem, USA) and platelet cationic protein (TKB) obtained from human platelets by the method [16] were used.

The activity of the claimed antimicrobial agents and comparison drugs in relation to various types of microorganisms was tested as follows.

Daily agar cultures of microorganisms were washed off with physiological saline and microbial suspensions containing 10 ⁴ CFU / ml were prepared. The tested drugs (the claimed antimicrobial agent, lysozyme and TKB) were dissolved in physiological saline at a rate of 10 μg / ml, after which serial dilutions of each drug were prepared.

To 0.1 ml of suspension of the tested microorganism strain, 0.9 ml of dilution of the antimicrobial preparation was added (0.9 ml of physiological saline was added to control samples instead of dilution of the antimicrobial preparation). The resulting mixture was incubated for 40-60 minutes at 37 ° C. After incubation, 0.2 ml of the experimental and control tubes were plated on Petri dishes with 5% blood agar. Crops were incubated 24 hours at 37 ° C. After incubation, the number of grown colonies on the experimental and control plates was counted. The minimum bactericidal concentration of the antimicrobial drug was taken as the concentration that suppressed 50% of the bacterial colonies compared with the control.

The results of a comparative determination of the antimicrobial activity of various drugs are presented in table 1.

Table 1.
Comparative characteristics of the sensitivity of microorganisms to antimicrobial agents (μg / ml). Type of microorganisms lysozyme TKB The inventive antimicrobial agent E.coli K12 > 500.0 200,0 100.0 S.aureus 209P > 100.0 50,0 10.0 B.cereus 569 50,0 20,0 0.5

As can be seen from table 1, the mixture of peptides from human platelets has a more pronounced antimicrobial effect compared to analogues due to the synergistic antimicrobial action of various peptides. Thus, the claimed antimicrobial agent is more effective in the manifestation of antimicrobial action in comparison with analogues.

The presence of peptides with antimicrobial activity in rabbit platelets is known [12, 23].

The authors first established the presence of peptides with antimicrobial activity in platelets of cattle. Platelet mass was obtained from fresh citrate bovine blood by fractional centrifugation, which was washed 3-4 times with medium 199. The resulting platelet mass was resuspended in 5 volumes of glacial acetic acid and frozen for 24 hours at a temperature of -15 ° C. After 24 hours, the platelet suspension was thawed and centrifuged at 1000 g for 30 minutes at room temperature. The obtained supernatant was tested for protein content by a known method [22] and antimicrobial activity in relation to E. coli K12, S.aureus 209P, B.cereus 569 according to the method described above. It was found that the cattle platelet acid extract had a bactericidal effect (MBK50) against E. coli K12 at a concentration of 35 μg / ml, S.aureus 209P - 5 μg / ml, B.cereus 569 - 0.5 μg / ml

The authors first established the presence of peptides with antimicrobial activity in pig platelets. From fresh citrate pig blood, platelet mass was obtained by fractional centrifugation, which was washed 3-4 times with medium 199. The resulting platelet mass was resuspended in 5 volumes of glacial acetic acid and frozen for 24 hours at a temperature of (-15 ° C). After 24 hours, the platelet suspension was thawed and centrifuged at 1000 g for 30 minutes at room temperature. The obtained supernatant was tested for protein content by a known method [22] and antimicrobial activity in relation to E. coli K12, S.aureus 209P, B.cereus 569 according to the method described above. It was found that the acid extract of pig platelets had a bactericidal effect (MBK50) with respect to E. coli K12 at a concentration of 100 μg / ml, S.aureus 209P - 30 μg / ml, B.cereus 569 - 5 μg / ml.

An antimicrobial agent from platelets is obtained as follows:

- fresh blood is collected in plastic containers, a 3.8% sodium citrate solution is added in a ratio of 9 parts of blood: 1 part of a 3.8% sodium citrate solution;

- get the platelet-rich supernatant by centrifuging blood at room temperature at 250 g for 30 minutes;

- platelets are precipitated from the supernatant by centrifugation at 1000 g for 30 minutes;

- the resulting platelet mass is washed 3-4 times with medium 199;

- the washed platelet mass is resuspended in 5-6 volumes of glacial (70%) acetic acid and incubated at -15 ° - (-20 °) C for 18-24 hours;

- after incubation, the platelet suspension is thawed and centrifuged at 1000 g for 30 minutes at room temperature;

- the resulting supernatants are subjected to sequential ultrafiltration through dialysis membranes (for example Spectra / Por), delaying products with a molecular weight of more than 15,000 daltons and passing products and salts with a molecular weight of less than 500 daltons;

- the ultrafiltrate concentrate is applied to a 10 × 250 mm column with Sephadex (for example, G-25 or G-50). Elution is carried out by a linear gradient of acetonitrile (from 0% to 60%) with the addition of a 0.1% solution of triphosphoric acid;

- peptide fractions are collected, combined, the protein content is determined according to Lowry [22] and lyophilized.

The agent of the present invention will be administered in an amount that is effective. The term "effective amount" means an amount capable of preventing or reducing the severity or development of a condition or symptom being treated. It will be obvious to a person skilled in the art that an effective amount of an antimicrobial agent will depend, inter alia, on the disease, dosage, route of administration, on whether the agent of the present invention is administered alone or in combination with other drugs, on the half-life of the composition in serum and general health of the patient.

The agent of the present invention is preferably administered in a composition comprising a pharmaceutically acceptable carrier. The term "pharmaceutically acceptable carrier" means a carrier that does not cause any adverse effects in patients to whom it is administered. Such pharmaceutically acceptable carriers are well known in the art.

The agents of the present invention can be incorporated into pharmaceutical compositions in accordance with well-known techniques. See, for example, suitable formulations described in Remington's Pharmaceutical Science E.W. Martin. The pharmaceutical composition of the claimed agent can be formulated in a variety of forms, including liquid, gel, lyophilized, or any other suitable form. The preferred form will depend on the particular symptom being treated and will be apparent to one skilled in the art.

The pharmaceutical composition of the antimicrobial agent can be administered orally, in the form of an aerosol, intramuscularly, intraperitoneally, intradermally or subcutaneously, or in any other suitable manner. The preferred route of administration will depend on the particular symptom being treated and will be apparent to one skilled in the art. An antimicrobial pharmaceutical composition may be administered in combination with other drugs. These agents may be included as part of the same pharmaceutical composition or may be administered separately from the antimicrobial agent either simultaneously or in accordance with any other suitable treatment regimen. In addition, the pharmaceutical composition of the antimicrobial agent can be used as a supplement to other courses of treatment.

A pharmaceutical composition comprising an effective amount of an antimicrobial agent may further comprise one or more antimicrobial compounds to enhance the antimicrobial effect. The added antimicrobial compound, as a rule, depends on the type of microorganisms, their type sensitivity to antimicrobial compounds, which is determined by conventional methods and is obvious to a person skilled in this field.

Examples of major classes of antibiotics for use in the pharmaceutical composition include aminoglycosides (e.g. tobramycin), penicillins (e.g. piperacillin), cephalosporins (e.g. ceftazidime), fluoroquinolones (e.g. ciprofloxacin), carbapenems (e.g., imipenem), tetracyclines and macrol e.g. erythromycin and clarithromycin).

An antibiotic added to a pharmaceutical composition containing an effective amount of an antimicrobial agent to enhance the antimicrobial effect is selected depending on the sensitivity of microorganisms to this antibiotic, which is determined by conventional methods. In addition, the added antibiotic, in addition to the ones described above, includes aminoglycosides (amikacin, gentamicin, kanamycin, tobramycin, streptomycin, azithromycin, clarithromycin, erythromycin), beta-lactams or penicillins (for example, penicillin V, penicillin, amicillin, oxylcillicin amine , carbenicillin, azlocillin, piperacillin), cephalosporins (e.g. cephalotin, cefazolin, cefaclor, cefamandole, cefuroxime, cefonicide, cefmetazole, cefotetan, cefprosil, loracarbef, cefetimetsef, cefotsef, cefotsef, cefotsef iakson, ceftazidime, cefepime, cefixime, cefpodoxime, cefsulodin). Other classes of antibiotics include carbapenems (e.g., imipenem), monobactams (e.g., aztreonam), quinolones (e.g., phloxacin, nalidixic acid, norfloxacin, ciprofloxacin, ofloxacin, enoxacin, lomefloxacin, cinoxacin), tetracycline, e.g. and glycopeptides (e.g., vancomycin, teicoplanin). Other antibiotics include chloramphenicol, clindamycin, sulfomethoxazole, trimethoprim, nitrofuran, rifampicin.

The pharmaceutical formulations of the antimicrobial agent may be in the form for oral or parenteral administration for the treatment or prevention of infectious diseases.

The agent (one or in combination with one or more antimicrobial compounds) is mixed with conventional pharmaceutical carriers and excipients and used in the form of tablets, capsules, suppositories, ointments, injectable solutions, etc. The type of media depends on the intended use. Compositions comprising the agents of the present invention contain an effective amount of the active ingredient, which depends on many factors, including sensitivity to the antimicrobial agent of infectious agents, and is determined by known methods [24, 25, 26].

The agents of the present invention can be administered orally, parenterally (including subcutaneous injections, intravenous, intramuscular, intravenous injections or infusions), by inhalation, rectally, topically cutaneous.

Such pharmaceutical compositions may be provided in the form of orally administered suspensions, tablets or capsules; sprays; sterile injectable preparations, for example, in the form of aqueous suspensions or lyophilized powders for the subsequent preparation of solutions; candles; powders; bactericidal napkins.

For oral use in suspension formulations, the compositions are prepared according to methods known in the art of pharmaceutical formulations, and they may contain microcrystalline cellulose to provide mass, alginic acid or sodium alginate as a suspending agent, methyl cellulose as a viscosity enhancer and sweetening agents and / or perfumes known in this field. In the form of tablets or capsules, such compositions may contain microcrystalline cellulose, calcium phosphate, lactose and / or other excipients, binders, diluents, disintegrants, diluents and lubricants known in the art.

When used in the form of sprays or aerosols, such compositions are prepared by methods well known in the field of pharmaceutical procedures, and they can be produced in the form of solutions in physiological saline, using benzoic acid or other suitable preservatives, adsorption promoters to enhance bio-applicability, and / or other solubilizing or dispersing agents known in the art.

Injectable solutions or suspensions may be formed according to known methods using non-toxic, parenterally applicable diluents or solvents such as mannitol, 1,3-butanediol, water, Ringer's solution, isotonic sodium chloride solution, etc.

For rectal administration in the form of suppositories, such compositions can be prepared by mixing the active ingredients with a non-irritating excipient such as cocoa butter, synthetic glyceride esters or polyethylene glycols, which are solids at ordinary temperatures, but liquefy and / or dissolve in the rectal cavity to release the active ingredients .

For topical use in the form of powders, such compositions are prepared by mixing the active ingredients with inert carriers known to those skilled in the art, such as alumina, calcium carbonate, sodium hydrogen carbonate, etc. Bactericidal wipes are prepared by soaking the appropriate paper and / or cotton-gauze media with a solution or suspension of the active ingredients.

Examples of specific performance.

Example 1. Obtaining an antimicrobial agent from platelets of cattle.

From 1000 ml of fresh nitrate bovine blood by centrifugation of blood at room temperature at 250 g for 30 minutes received platelet-enriched supernatant. Platelets were pelleted by centrifugation at 1000 g for 30 minutes. 50 ml of the obtained platelet mass was washed 4 times with 199 medium, after which it was resuspended in 300 ml of glacial (70%) acetic acid and incubated at -15 ° - (-20 °) C for 24 hours. After incubation, the platelet suspension was thawed and centrifuged at 1000 g for 30 minutes at room temperature. The resulting supernatants were subsequently filtered through Spectra / Por Biotech Regenerated Cellulose Dialysis Membrane MWCO 15000 dialysis membranes (retention products with a molecular weight of over 15,000 daltons) and Spectra / Por Biotech Cellulose Ester MWCO 500 (passing products and salts with a molecular weight of less than 500 daltons). The ultrafiltrate concentrate was applied to a 10 × 250 mm column with Sephadex G-50. Elution was carried out by a linear gradient of acetonitrile (from 0% to 60%) with the addition of a 0.1% solution of triphosphoric acid. The resulting peptide fractions were collected, combined, the total protein content was determined, which was 260 μg / ml, and lyophilized.

Example 2. Determination of the activity of an antimicrobial agent isolated from platelets of cattle.

The activity of the antimicrobial agent obtained according to example 1 in relation to various types of microorganisms was tested as follows.

Daily agar cultures of microorganisms were washed off with physiological saline and microbial suspensions containing 10 ⁴ CFU / ml were prepared. The lyophilized antimicrobial agent was dissolved in physiological saline at a rate of 10 μg / ml, after which serial dilutions of the antimicrobial agent were prepared.

Table 2.
The sensitivity of microorganisms to antimicrobial agents (MBK50), isolated from platelets of cattle. Type of microorganisms Antimicrobial protein content at effective dilution (μg / ml) B.subtilis 6633 0.02 S.aureus 6538P 0.4 M.lysodeikticus 2665 0.33 B.cereus 569 0.02 E.coli K12 1.3 S.epidermidis 14990 0.4 P.aerugmosa 219 0.65

To 0.1 ml of suspension of the tested strain of microorganisms, 0.9 ml of dilution of the antimicrobial agent was added (0.9 ml of physiological saline was added to the control samples instead of dilution of the antimicrobial agent). The resulting mixture was incubated for 40-60 minutes at 37 ° C. After incubation, 0.2 ml of the experimental and control tubes were plated on Petri dishes with 5% blood agar. Crops were incubated 24 hours at 37 ° C. After incubation, the number of grown colonies on the experimental and control plates was counted. The minimum bactericidal concentration of the antimicrobial agent was taken as the concentration that suppressed 50% of the bacterial colonies compared to the control.

The results of determining the activity of the antimicrobial agent obtained according to example 1 are presented in table 2.

Example 3. Obtaining an antimicrobial agent from pig platelets.

Platelet-rich supernatant was obtained from 700 ml of fresh citrated pig blood by centrifugation of blood at room temperature at 250 g for 30 minutes. Platelets were pelleted by centrifugation at 1000 g for 30 minutes. 25 ml of the obtained platelet mass was washed 4 times with 199 medium, after which it was resuspended in 150 ml of glacial (70%) acetic acid and incubated at -15 ° - (-20 °) C for 24 hours. After incubation, the platelet suspension was thawed and centrifuged at 1000 g for 30 minutes at room temperature. The resulting supernatants were subsequently filtered through Spectra / Por Biotech Regenerated Cellulose Dialysis Membrane MWCO 15000 dialysis membranes (retention products with a molecular weight of over 15,000 daltons) and Spectra / Por Biotech Cellulose Ester MWCO 500 (passing products and salts with a molecular weight of less than 500 daltons). The ultrafiltrate concentrate was applied to a 10 × 250 mm column with Sephadex G-50. Elution was carried out by a linear gradient of acetonitrile (from 0% to 60%) with the addition of a 0.1% solution of triphosphoric acid. The resulting peptide fractions were collected, combined, the total protein content, which was 675 μg / ml, was determined and lyophilized.

Example 4. Determination of the activity of an antimicrobial agent isolated from pig platelets.

Table 3.
The sensitivity of microorganisms to antimicrobial agents (MBK50), isolated from pig platelets. Type of microorganisms Antimicrobial Dilution Protein Content (μg / ml) B.subtilis 6633 0.09 S.aureus 6538P 2.0 M.lysodeikticus 2665 0.5 B.cereus 569 0.08 E.coli K12 5,0 S.epidermidis 14990 2,5 P.aerugmosa 219 3,5

The antimicrobial activity obtained according to example 3 in relation to various types of microorganisms was tested according to example 2.

The results of determining the activity of the antimicrobial agent obtained according to example 3 are presented in table 3.

Example 5. Determination of the activity of an antimicrobial agent from pig platelets in combination with antibiotics.

To determine the antimicrobial activity of pig platelets in combination with antibiotics, we used the clinical strain S.epidermidis 312 from the collection of the Institute of Cellular and Intracellular Symbiosis of the Ural Branch of the Russian Academy of Sciences, isolated from a patient with chronic prostatitis.

By the method of serial dilution [27], the sensitivity (minimum inhibitory concentration — MIC) of S.epidermidis to antibiotics was determined. Ampicillin, gentamicin, carbenicillin, kanamycin, vancomycin, cefazolin were used as test antibiotics. The final concentration of bacteria in the antibiotic medium was 10 ⁵ CFU / ml. After 24 hours of incubation at 37 ° C, the results were taken into account. For IPC, antibiotic dilution was taken, in which no visible bacterial growth was observed.

The results are presented in table 4.

According to the method described in example 2, the sensitivity of S.epidermidis 312 strain to an antimicrobial agent isolated from pig platelets was determined according to example 4. It was found that 50% growth inhibition of S.epidermidis was observed at an antimicrobial concentration of 10 μg / ml.

At the second stage, test tubes containing an antimicrobial agent at a final concentration of 10 μg / ml and a suspension of S.epidermidis at a final concentration of 10 ⁵ CFU / ml were added with bacteriostatic concentrations of antibiotics. After 24 hours of incubation at 37 ° C, the results were taken into account. For IPC, antibiotic dilution was taken, in which no visible bacterial growth was observed. The results are presented in table 5.

Table 4.
Sensitivity of S.epidermidis 312 to Antibiotics Antibiotic IPC (μg / ml) Ampicillin 1,0 Gentamicin 2.0 Carbenicillin 4.0 Kanamycin 16,0 Vancomycin 4.0 Cefazolin 0.5 Table 5.
The sensitivity of S.epidermidis 312 to antibiotics in combination with an antimicrobial agent at a concentration of 10 μg / ml Antibiotic IPC (μg / ml) Ampicillin 0.25 Gentamicin 1,0 Carbenicillin 3.0 Kanamycin 10.0 Vancomycin 2.0 Cefazolin 0.25

Example 6. Determination of the activity of an antimicrobial agent from platelets of cattle in combination with antibiotics.

To determine the activity of an antimicrobial agent from cattle platelets in combination with antibiotics, we used the clinical strain S.epidermidis 312 from the collection of the Institute of Cellular and Intracellular Symbiosis of the Ural Branch of the Russian Academy of Sciences, isolated from a patient with chronic prostatitis.

According to the method described in example 2, the sensitivity of S.epidermidis 312 strain to an antimicrobial agent isolated from cattle platelets was determined according to example 1. It was found that 50% growth inhibition of S.epidermidis was observed at an antimicrobial concentration of 5 μg / ml

By the method described in example 5, MPC S.epidermidis 312 was determined to a number of antibiotics.

The results are presented in table 4.

At the second stage, test tubes containing an antimicrobial agent at a final concentration of 5 μg / ml and a suspension of S.epidermidis at a final concentration of 10 ⁵ CFU / ml were added with bacteriostatic concentrations of antibiotics. After 24 hours of incubation at 37 ° C, the results were taken into account. For IPC, antibiotic dilution was taken, in which no visible bacterial growth was observed. The results are presented in table 6.

Table 6.
The sensitivity of S.epidermidis 312 to antibiotics in combination with an antimicrobial agent at a concentration of 5 μg / ml Antibiotic IPC (μg / ml) Ampicillin 0.1 Gentamicin 0.5 Carbenicillin 2.0 Kanamycin 8.0 Vancomycin 1,0 Cefazolin 0.1

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Claims (8)

1. An antimicrobial agent, which is a peptide-containing fraction of cattle platelets with a molecular weight of 0.5-15 kDa, obtained by freezing and thawing platelet mass at a temperature of -15 ÷ (-20) ° C for 24 hours, centrifugation at 1000 g filtering the supernatant through dialysis membranes 15000 and 500; and eluting the peptide-containing concentrate with a linear gradient of acetonitrile from Sephadex G-50. 2. An antimicrobial agent, which is a peptide-containing fraction of pig platelets with a molecular weight of 0.5-15 kDa, obtained by freezing and thawing platelet mass at a temperature of -15 ÷ (-20) ° C for 24 hours, centrifugation at 1000 g, filtration supernatant through dialysis membranes 15,000 and 500; and eluting the peptide-containing concentrate with a linear gradient of acetonitrile from Sephadex G-50. 3. A pharmaceutical composition comprising an effective amount of an antimicrobial agent according to any one of claims 1 and 2, and a pharmaceutically acceptable carrier. 4. The pharmaceutical composition according to claim 3, characterized in that it further comprises one or more antimicrobial compounds. 5. The pharmaceutical composition according to claim 4, characterized in that the antimicrobial compound is an antibiotic, antifungal or antiviral agent. 6. The pharmaceutical composition according to claim 5, characterized in that the antibiotic is selected from the group consisting of aminoglycosides, penicillins, cephalosporins, carbapenems, monobactams, quinolones, tetracyclines, glycopeptides, nitrofurans, rifampicin, clindamycin, chloramphenicol, trimethazole, 7. The pharmaceutical composition according to claim 6, characterized in that the antibiotic is amikacin, gentamicin, kanamycin, tobramycin, streptomycin, azithromycin, clarithromycin, erythromycin, penicillin G, penicillin V, methicillin, oxacillin, ampicillin, amoxicillin, carbamycillin, amoxicillin, meslocillin, azlocillin, piperacillin, cefalotin, cefazolin, cefaclor, cefamandol, cefoxitin, cefuroxime, cefonicide, cefmetazole, cefotenan, cefprozil, lofarcarbef, cefetamet, cefefeximone, cefeximone, cefeximone, cefeximone, cefeximone, cefeximone, cefeximone, cefeximone Xim, cefpodoxime, cefsulodin, imipenem, aztreonam, fleroxacin, nalidixic acid, norfloxacin, ciprofloxacin, ofloxacin, enoxacin, lomefloxacin, cinoxacin, doxycycline, minocycline, tetracycline, vancomycin or teicoplanin. 8. The pharmaceutical composition according to any one of claims 3 to 7, characterized in that it is in the form of powder for injection, tablets, capsules, injection, suppositories, ointment, cream, spray, gel, bactericidal wipes, powders.