New Potentially Probiotic Strains Isolated from Humans - Comparison of Properties with Strains from Probiotic Products and ATCC Collection.

Lactic acid bacteria are used in various types of probiotic products. Due to the constantly growing probiotics market, new strains with pro-health properties are sought. The present study compared 39 strains of Lactobacillus, Lacticaseibacillus, and Lactiplantibacillus, isolated from probiotic products and healthy people. The current research aimed to search for new, potentially probiotic strains. For this purpose the relationship between Lactobacillaceae strains was carried out; moreover, the basic properties of probiotic microorganisms, such as survival at low pH and bile salt environment, antibiotic susceptibility, aggregation and antagonism were estimated. The properties of these isolates were also compared with the properties of probiotic strains from the ATCC collection. In comparing the genetic relationship (PFGE method) between the tested isolates, it was observed that some of them show a high degree of similarity. All tested strains tolerated an environment with a pH value of 3.0, and the addition of 0.3% bile salt; showed auto-aggregation properties and displayed antagonism against pathogenic microorganisms. In the present study, the bacteria were susceptible to tetracycline, chloramphenicol and ampicillin; the resistance to vancomycin depended on the bacteria type. All the properties were strain-depended. Most of the tested strains had properties comparable to the reference strains. Three L. acidophilus strains isolated from cervical swabs seem to be promising candidates for probiotic strains.

Microbiological Testing of Probiotic Preparations.

Probiotic microorganisms that are potentially beneficial to the health of the host are commercially available in a great variety of products. Not all microorganism strains present in products have proven beneficial to the health properties. These products include not only foodstuffs but also dietary supplements, food for special medical purposes, medicinal products, as well as cosmetics and medical devices. These products contain from one to a dozen bacterial strains of the same or different species and sometimes also fungal strains. Since the pro-health effects of probiotics depend on a specific strain, the number of its cells in a dose, and the lack of pathogenic microorganisms, it is extremely important to control the quality of probiotics. Depending on the classification of a given product, its form, and its content of microorganisms, the correct determination of the number of microorganisms and their identification is crucial. This article describes the culture-dependent and culture-independent methods for testing the contents of probiotic microorganisms, in addition to biochemical and genetic methods of identification. The microbiological purity requirements for various product categories are also presented. Due to numerous reports on the low quality of probiotic products available on the market, it is important to standardise research methods for this group of products and to increase the frequency of inspections of these products.

Dental Implant Healing Screws as Temporary Oral Drug Delivery Systems for Decrease of Infections in the Area of the Head and Neck.

Background: Periimplantitis is continuously one of major threats for the uneventful functioning of dental implants. Current approaches of drug delivery systems are being more commonly implemented into oral- and maxillofacial biomaterials in order to decrease the risk of implant failure due to bacterial infection. Silver nanoparticles and their compounds have been proven in eradicating oral bacteria responsible for peri-implant infections. Nevertheless, their evaluation as coating for implant abutments has not been extensively evaluated so far. This article describes a novel coating consisting of zinc oxide (ZnO) and silver (Ag) nanoparticles (NPs). This coating was used to modify healing abutments that could be used as drug delivery systems in oral implantology. Materials and Method: Nanoparticles with a ZnO + 0.1% Ag composition were produced by microwave solvothermal synthesis and then incorporated into the surface of titanium healing abutments by high-power ultrasonic deposition. Surface morphology, roughness, wettability were evaluated. Ability of biofilm formation inhibition was tested against S. mutans, S. oralis, S. aureus and E. coli. Results: ZnO+0.1%Ag NPs were sufficiently deposed on the surface of the abutments creating nanostructured coating which increased surface roughness and decreased wettability. Modified abutments significantly decreased bacterial biofilm formation. Bacteria present in SEM studies were unlikely to settle and replicate on the experimental abutments as their cells were rounded, insufficiently spread on the surface and covered with released NPs. Conclusion: Experimental nanostructured abutments were easily manufactured by high-power ultrasonic deposition and provided significant antibacterial properties. Such biomaterials could be used as temporary drug delivery abutments for prevention and treatment of intra- and extraoral peri-implant infections in the area of the head and neck.

Nanoparticles And Human Saliva: A Step Towards Drug Delivery Systems For Dental And Craniofacial Biomaterials.

AIM: The aims of this study were to investigate new nano-formulations based on ZnO and Ag nanoparticle (NP) compounds when used against clinical strains of oral gram-positive and gram-negative bacteria, and to examine the stability and behaviour of nano-formulation mixtures in saliva based on different compositions of Ag NPs, ZnO NPs and ZnO+x·Ag NPs. Methods: ZnO NPs with and without nanosilver were obtained by microwave solvothermal synthesis. Then, antibacterial activity was evaluated against bacteria isolated from human saliva. Behavior and nanoparticle solutions were evaluated in human saliva and control (artificial saliva and deionized water). Results were statistically compared. RESULTS: The NP mixtures had an average size of 30±3 nm, while the commercial Ag NPs had an average size of 55±5 nm. The suspensions displayed differing antibacterial activities and kinetics of destabilisation processes, depending on NPs composition and fluid types. CONCLUSION: The present study showed that all NPs suspensions displayed significant destabilisation and high destabilisation over the 24 h of the analyses. The agglomeration processes of NPs in human saliva can be reversible.

Occurrence of antimicrobial agents, drug-resistant bacteria, and genes in the sewage-impacted Vistula River (Poland).

Antimicrobial agents (antimicrobials) are a group of therapeutic and hygienic agents that either kill microorganisms or inhibit their growth. Their occurrence in surface water may reveal harmful effects on aquatic biota and challenge microbial populations. Recently, there is a growing concern over the contamination of surface water with both antimicrobial agents and multidrug-resistant bacteria. The aim of the study was the determination of the presence of selected antimicrobials at specific locations of the Vistula River (Poland), as well as in tap water samples originating from the Warsaw region. Analysis was performed using the liquid chromatography-electrospray ionization-tandem mass spectrometry method. In addition, the occurrence of drug-resistant bacteria and resistance genes was determined using standard procedures. This 2-year study is the first investigation of the simultaneous presence of antimicrobial agents, drug-resistant bacteria, and genes in Polish surface water. In Poland, relatively high concentrations of macrolides are observed in both surface and tap water. Simultaneous to the high macrolide levels in the environment, the presence of the erm B gene, coding the resistance to macrolides, lincosamides, and streptogramin, was detected in almost all sampling sites. Another ubiquitous gene was int1, an element of the 5'-conserved segment of class 1 integrons that encode site-specific integrase. Also, resistant isolates of Enterococcus faecium and Enterococcus faecalis and Gram-negative bacteria were recovered. Multidrug-resistant bacteria isolates of Gram-negative and Enterococcus were also detected. The results show that wastewater treatment plants (WWTP) are the main source of most antimicrobials, resistant bacteria, and genes in the aquatic environment, probably due to partial purification during wastewater treatment processes.

Oral microbiome and peri-implant diseases: where are we now?

Peri-implant infective diseases (PIIDs) in oral implantology are commonly known as peri-implant mucositis (PIM) and periimplantitis (PI). While PIM is restricted to the peri-implant mucosa and is reversible, PI also affects implant-supporting bone and, therefore, is very difficult to eradicate. PIIDs in clinical outcome may resemble gingivitis and periodontitis, as they share similar risk factors. However, recent study in the field of proteomics and other molecular studies indicate that PIIDs exhibit significant differences when compared to periodontal diseases. This review aims to elucidate the current knowledge of PIIDs, their etiopathology and diversified microbiology as well as the role of molecular studies, which may be a key to personalized diagnostic and treatment protocols of peri-implant infections in the near future.

In vitro studies of nanosilver-doped titanium implants for oral and maxillofacial surgery.

The addition of an antibacterial agent to dental implants may provide the opportunity to decrease the percentage of implant failures due to peri-implantitis. For this purpose, in this study, the potential efficacy of nanosilver-doped titanium biomaterials was determined. Titanium disks were incorporated with silver nanoparticles over different time periods by Tollens reaction, which is considered to be an eco-friendly, cheap, and easy-to-perform method. The surface roughness, wettability, and silver release profile of each disc were measured. In addition, the antibacterial activity was also evaluated by using disk diffusion tests for bacteria frequently isolated from the peri-implant biofilm: Streptococcus mutans, Streptococcus mitis, Streptococcus oralis, Streptococcus sanguis, Porphyromonas gingivalis, Staphylococcus aureus, and Escherichia coli. Cytotoxicity was evaluated in vitro in a natural human osteoblasts cell culture. The addition of nanosilver significantly increased the surface roughness and decreased the wettability in a dose-dependent manner. These surfaces were significantly toxic to all the tested bacteria following a 48-hour exposure, regardless of silver doping duration. A concentration of 0.05 ppm was sufficient to inhibit Gram-positive and Gram-negative species, with the latter being significantly more susceptible to silver ions. However, after the exposure of human osteoblasts to 0.1 ppm of silver ions, a significant decrease in cell viability was observed by using ToxiLight™ BioAssay Kit after 72 hours. Data from the present study indicated that the incorporation of nanosilver may influence the surface properties that are important in the implant healing process. The presence of nanosilver on the titanium provides an antibacterial activity related to the bacteria involved in peri-implantitis. Finally, the potential toxicological considerations of nanosilver should further be investigated, as both the antibacterial and cytotoxic properties may be observed at similar concentration ranges.

Assessment of the Microbiological Status of Probiotic Products.

The aim of this study was to perform the microbiological analysis of quality of 25 probiotic products, available on the Polish market. Analysis of bacterial viability in probiotic products showed that not all of these preparations possess a suitable number of bacteria. Moreover, some of the tested probiotic products contained bacterial strains other than those declared by the manufacturer. All tested strains recovered from probiotic products were found to be resistant to metronidazole and susceptible to nitrofurantoin. The susceptibility to other antibiotics was strain specific. Probiotic products should be subject to regular and thorough inspection by appropriate institutions.

[Evaluation of biocidal properties of silver nanoparticles against cariogenic bacteria]. / Ocena bakteriobójczej aktywnosci koloidalnego roztworu nanoczastek srebra w stosunku do bakterii próchnicotwórczych.

INTRODUCTION: Antimicrobial properties of silver nanoparticles (SNP's) have been recentl well evaluated, and now are being considered as excellent candidates for therapeutic purposes. It is confirmed, that various solutions of colloidal SNP's possess significant antibacterial properties against such species as: Staphylococcus aureus, Staphylococcus epidermidis, Escherichia coli, Pseudomonas aeruginosa even at low concentrations, although there have been so far only a few researches evaluating antimicrobial activity of SNP's against cariogenic bacteria: Streptococcus mutans, Streptococcus salivarius and Streptococcus mitis responsible for initiation of dental carries. Tooth decay is infectious disease an worldwide, which may occur in patients of every age. Nanotechnology creates a new approach of designing of medical devices preventing or reducing bacterial colonization. METHODS: Colloidal silver solution (CSS) of concentration 350 ppm was used in this research. Nanoparticles size, shape and solution stability were evaluated. 16 strains of cariogenic bacteria, 4 isolates of each species: S. mutans, S. salivarius, S. sanguinis and S, mitis were obtained from plaque swabs of 7 patients treated for dental carries at Department of Conservative Dentistry, Medical University of Warsaw. MIC and MBC values for CSS's were evaluated. RESULTS: CSS used in this research is of good stability. No agglomeration or coalescence was observed during 24 hours of experiment. Silver nanoparticles were of round shape and had mean size of 67 nm. MIC values were: 12-25 ppm for S. salivarius, 25 ppm for S. sanguinis, 50-100 ppm for S. mitis and 50 ppm for S. mutans, while MBC values after 1 hour of bacterial contact with nanoparticles were 200-350 ppm for all cariogenic bacterial species. After 24 hours of contact MBC values were: 25-50 ppm for S. salivarius and S. sanguinis, 100-200 ppm for S. mitis and 200 ppmfor S. mutans. CONCLUSIONS: Antimicrobial properties of CSS depend on nanoparticles concentration and interaction time with bacteria. The susceptibility of cariogenic oral streptococci to silver nanoparticles is diversified. Sufficient concentration which inhibited all cariogenic bacteria in our research was 200 ppm after long (24 hours) period of silver nanoparticles interaction with bacteria.

[Microbiological characteristics of selected liquid soaps for hands washing]. / Mikrobiologiczna charakterystyka wybranych plynnych produktów stosowanych do mycia rak.

INTRODUCTION: According to common belief, supported by the authority of the World Health Organization - WHO, the common (social) hand washing is the simplest, cheapest and the most effective way of reduction the hospital-acquired infections. For this purpose products of"liquid soaps", present in a large number on the market, are most often applied. Microbiological status (microbiological purity and antimicrobial activity) of"liquid soaps" available on the Polish market is not known, because relevant routinely studies have not been performed. Only the antibacterial and / or antifungal activity of certain formulations is sometimes assessed, especially when the manufacturer suggests the standardized application of the products for surgical or hygienic procedures. The aim of this study was to determine the microbiological quality, especially microbiological purity and antimicrobial activity of the selected hands washing products, presents on the Polish market. METHODS: The 12 selected commercial products, available on the market in Poland, dedicated for hands washing were included into study. Microbiological purity test was carried out in accordance with the Polish Pharmacopoeia (FP) monograph (FP monograph numbers correspond to numbers of the European Pharmacopoeia monograph- Ph. Eur.) No 2.6.12 "Microbiological examination of non-sterile products: microbial enumaration tests", and the monograph of FP No. 2.6.13 "Microbiological examination of non-sterile products: test for specified microorganisms". The following physico-chemical properties of soaps were examined: the pH of the formulations was measured according to the monograph FP No. 2.2.3. "Potentiometric determination of pH", the density of products was assayed according to the monograph FPNo. 2.2.5. "Relative density" and determination the water activity was performed by monograph FP No 2.9.39 "Water-solid interactions: determination of sorption-desorption isotherms and of water activity". Next, antibacterial and antifungal protection was determined in accordance with the monograph FP No 5.1.3. "Efficacy of antimicrobial preservation". The study of antimicrobial activity was carried out in accordance with PN-EN 1040 "Chemical disinfectants and antiseptics - Quantitative suspension test for the evaluation of basic bactericidal activity of chemical disinfectants and antiseptics - Test method and requirements (phase 1)". Finally, using the "time-kill" method the survival of microorganisms after different contact times of the products with bacteria and fungi were determined. RESULTS: All the examined products showed a very high microbiological purity. None of the formulations was characterized by a high acidity or alkalinity. All the analyzed products were slightly thicker than water, but such density of the preparation does not seem to be important parameter in the growth of microorganisms. The results of water activity estimation - the parameter indicating the presence of free, not chemically bound water stimulating microbes growth - do not show that low water content in the preparation may inhibit bacteria and fungi growth. Taking into consideration the antimicrobial protection of the products demonstrated in the tests carried out in accordance within FP monograph No 5.1.3. and PN-EN 1040, and analysing curves indicating killing rate of bacteria and fungi obtained by "time-kill" method, the microorganisms contaminating the products generally should not multiply in their environment, and gradually they die - what can take many hours or even days. CONCLUSIONS: The cases of bacterial infections connected with the usage of non-medical liguid soaps, applied in the health care units and described in the literature, should be considered as related rather to contamination of plastic packaging and dosage system, then to contamination of preparation itself inside the package. It was proved, that in all tested products amount of contaminating microbes diminishes in time. The dynamics of this process depends on the microorganisms character - bacteria dies quicker then fungi. The special attention should be given to washing, cleaning and disinfection of preparation dispensing systems, to avoid microbial contamination of product doses applied directly on the hands. It should be emphasized that only formulations containing antimicrobial agents in an appropriate amount, eliminate microorganisms from the skin surface fast and effectively. In case of hygienic and surgical procedures following the standardized manner in order to obtain required reduction rate of microorganisms in a short time - only products complying with appropriate EN standards are suitable. For these puroposes, the popular "liquid soaps" should not be used.

Examination of antimicrobial activity of selected non-antibiotic medicinal preparations.

The aim of this study was to detect and characterize the antimicrobial activity of non-antibiotic drugs, selected from the pharmaceutical products analyzed during the state control performed in National Medicines Institute, Warszawa, Poland. In 2010, over 90 pharmaceutical preparations have been randomly chosen from different groups of drugs. The surveillance study was performed on standard ATCC microbial strains used for drug control: S. aureus, E. coli, P. aeruginosa and C. albicans. It was shown that the drugs listed below inhibited growth of at least one of the examined strains: Arketis 20 mg tab. (paroxetine), Buvasodil 150 mg tab. (buflomedile), Halidor 100 mg tab. (bencyclane), Hydroxyzinum espefa 25 mg tab. (hydroxyzine), Norifaz 35 mg tab. (risedronate), Strattera 60 mg cap. (atomoxetine), Tamiflu 75 mg tab. (oseltamivir), Valpro-ratiopharm Chrono 300 mg tab. with longer dissolution (valproate), Vetminth oral paste 24 g+3 g/100 mL (niclozamide, oxybendazol). Strattera cap. showed broad activity spectrum. It inhibited growth of all examined strains (MIC of active substance -- atomoxetine ranged between 2.6-13 mg/mL).

[The evaluation of bacteria penetration by medical textiles for multiple use and disposable multilayer surgical drapes, according to the PN-EN ISO 22610 standard]. / Badanie przenikania bakterii przez tkaniny medyczne przeznaczone do wielokrotnego uzycia oraz wielowarstwowe oblozenia chirurgiczne jednorazowego uzytku, wedlug normy PN-EN ISO 22610.

INTRODUCTION: Cotton as well as synthetic textile medical products are widely used as barrier materials and individual protection against displacement of biological infectious factors. The required level of protection of these products for multiple use and disposable multilayer laminates against the penetration of microbes depends on the risk connected with type of surgical procedure defined in normative documents. METHODS. Cotton and syntetic medical textiles for multiple use, 30-times subjected to processes simulating conditions of the use as well as disposable multilayer surgical drapes were tested. Resistance to microbial wet penetration was conducted according to the PN-EN ISO 22610: 2007 standard. RESULTS: The barrier of cotton fabrics was reduced after first washing and then systematically grew after each often cycles to the value close to the value at the beginning. From the twentieth cycle of simulated conditions of the use, barrier index was reduced. The barrier of the synthetic textile stayed on the average level, while multilayer disposable products ensured the full impermeability for the bacteria. CONCLUSIONS: Natural cotton textiles for multiple use could be apply on operative blocks in limited range because of the changes of the cotton structure caused by repeated laundering process and sterilization. Synthetic materials also have limited application, although are more resistant to cleaning and sterilization processes. Disposable synthetic laminates with many layers use guarantee impermeability for bacteria and may be applied in operative blocks without restrictions.

[The estimation of penetrating of microbes by the protective clothing and textile medical devices, according to obligatory norms]. / Ocena, wedlug obowiazuj4cych norm, przenikania drobnoustrojów przez odziez ochronna i tkaniny medyczne.

Textile medical products can be widely used as barrier materials and individual protection against biological threats. Rules of introducing such products to market are regulated by the Directive 93/42/ EEC. Detailed requirements and testing methods of textile medical products are presented in obligatory norms. The required level of protection of these products against the penetration of microbes depends on the risk connected with planned type surgical procedure, the duration of the surgical intervention, risks of bleeding or presences of other body liquids of the patient and susceptibilities of the patient to infection. The aim of the study was to establish resistance of medical textiles to wet bacterial penetration. Materials were examined by the apparatus dedicated to this type of testing and obtained results were rated with reference to obligatory contracted requirements. assured Textiles laminated with foils possessed best protective proprieties, whereas medical products made from the cotton do not provide the sufficient level of the protection against microbes.

[Evaluation of selected alcoholic antiseptics activity against clinical bacterial strains]. / Ocena aktywnosci wybranych alkoholowych preparatów antyseptycznych w stosunku do klinicznych szczepów bakteryjnych.

The aim of this study was to evaluate antimicrobial activity of selected alcoholic antiseptics against clinical strains, which possessed in majority a high level of drug resistance: MRSA (7), MSSA (3), E. coli: (9): strains producing ESBL (4), P. aeruginosa: (4), E. cloacae: (3), K. pneumoniae: (3). These strains were defined by MIC value, using antibiotic agar dilution method according to NCCLS. Fourteen alcoholic antiseptics were used in this study. Beside alcohol, they contained other active substances like iodine, hydrogen peroxide, chlorhexidine. Some additional agents were included for easier application, such as: gelling, moisturizing, aromatic or coloring substances. The objective of this study was also to determine the dependence of bactericidal activity on preparations (concentration). Product undiluted and diluted two and four times in water was analyzed according to prEN 12054 standard; 30 seconds and 1 minute contact time was used. The obtained data indicate that all tested undiluted antiseptics possessed bactericidal activity described by producers. However antiseptics (dilution leads to decrease and even loss of bactericidal activity. Two-times dilution of gel almost completely inactivated the product. Antimicrobial activity after 30 seconds of contact time was not affected by presence of additional agents in the tested antiseptics.

Examination of antimicrobial activity of selected non-antibiotic drugs.

A variety of pharmaceutical preparations, which are applied in the management of non-infectious diseases, have shown in vitro some antimicrobial activity. These drugs are called "non-antibiotics". The aim of this study was to detect and characterize the antimicrobial activity of non-antibiotic drugs, selected from the preparations analysed during state control performed in the National Institute of Public Health in Poland. Over 180 of pharmaceutical preparations were randomly chosen from different groups of drugs. A surveillance study was performed on standard ATCC microbial strains used for drug control: S. aureus, E. coli, P. aeruginosa and C. albicans. It was shown that the drugs listed below inhibited growth of at least one of the examined strains: Actonel 5 mg tabl. (risedronate), Aldan 10 mg tabl. (amlodipine), Aleras 10 mg tabl. (cetirisine), Aspicam 15 mg tabl. (meloxicam), Baikadent 6 mg/g gel (flavons of Scutellariae), Debretin 100 mg tabl. (trimebutine), Ferro-Duo 100 mg tabl. (ferrum), Gastrovent 145 mg caps. (bismuth citrate), Ibum 200 mg caps., Upfen 200 mg tabl. (ibuprofen), Lastet 100 mg caps. (etoposide), Legalon 70 mg tabl. (sylimarin), Madopar 125 tabl. (benserazide, levodopa), Moxenil 100 mg tabl. (nimesulide), Neurotin 800 mg tabl. (gabapentin), Propranolol 40 mg tabl. (propranolol), Rexetin 20 mg tabl. (paroxetine), Salipax 20 mg caps. (fluoxetine), Selofen 10 mg caps. (zaleplon) Stenorol 0.6% powder (halofuginone), Stimuloton 50 mg tabl. (sertraline), Superoptim 0.3 mg tabl. (hipericine), Uversan 50 mg tabl. (arbutine from Arctostaphylos uva ursi). S. aureus strain was susceptible to the most of the drugs listed above. The lowest inhibitory concentration was found for sertraline and hipericine (0.16 and 0.075 mg/mL, respectively).

[Use of impedance test for testing effectiveness of drug preservatives]. / Zastosowanie metody impedymetrii w badaniu skutecznosci dzialania srodków konserwujacych leki.

Pharmacopoeias contain preservation efficacy test for estimating antimicrobial activity of chemical compounds added to pharmaceutical preparations in multidose containers in order to inhibit bioburden growth. This method involves the treating of preserved products with bacteria and yeast cells and monitoring the survival of microorganisms through the specified time periods up to 28 days. The last stage of assay--incubation and colony counting--is very time consuming. Recent advance in technology enables faster and more convenient detection in comparison to traditional methods. Impedance method is based on the principle that conductance and capacitance of cultivation medium increases when bacteria grow and metabolize, Impedance time detection is inversely proportional to initial bacterial population. Six different products were utilised throughout the study. The calibration curves were calculated for each of the tested strains by comparison between standard plate count method and detection time measured in Bactometer system. In our study log reduction calculated in alternative method were similar to those obtained in plate count assay. All of the tested preparations, except one, exhibited acceptable activity against bacteria and fungi and meet the pharmacopoeal requirements. The studies indicated a positive correlation between standard plate count results and impedance reading. The procedure with the usage of Bactometer, provides a rapid and accurate system for the determination of bacterial content.

[Use of impedance methods for testing bactericidal activity of antiseptics]. / Zastosowanie metody impedymetrii do badania aktywnosci bakteriobójczej srodków antyseptycznych.

Standards PN-EN 1040 and EN 12054 describe test methods and minimum requirements for bactericidal activities of antiseptics. However, standard procedures are time consuming and require 48 hours of incubation. New alternative technique based on impedimetric procedure provides possibilities to reduce this time to several hours. The Bactometer (BioMerieux, Vitek System, USA) is a fully automated impedance technology system used to microbial quantitation of products. Impedance measures microbial activity by electrical methods. The aim of the study was to adaptate the impedimetric method utilising Bactometer--system to microbiological activity control of chemical antiseptics. Eight different products were utilised throughout the study. The samples for classical and alternative method were prepared in the same way as described in standards. The method of choice was dilution-neutralization method. All procedures conducted in Bactometer were verified by plate count method. The high correlation was observed between results obtained by normative methods and impedimetric measurement. All tested products meet requirements. The procedure utilising the Bactometer, provides a rapid and accurate system for the determination of bacterial content. The results of validation carried out during this study indicate, possibility to use impedimetric method alternatively to traditional methods.