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Antibiotics are probably the most successful family of drugs so far developed for improving human health. Because of increasing resistance to antibiotics of many bacteria, plant extracts and plant compounds are of new interest as antiseptics and antimicrobial agents in medicine. In this study, we researched antimicrobial effects of extracts of some medical plants (Tussilagofarfara, Equisetum arvense, Sambucusnigra, Aesculushippocastanumand Taraxacumofficinale) from Slovakia to antibiotic resistant and antibiotic sensitive bacteria isolated from milk of cows and mare, which were breeded in different conditions. Microorganisms which were used in this experiment we isolated from milk from conventional breeding of cows (tenE. coli strains) and from ecological breeding of Lipicanmare (tenE. coli strains) by sterile cotton swabs. For antibiotic susceptibility testing was used disc diffusion method according by EUCAST. After dried at room temperature we weighed 50 g of crushed medical plants (parts) and it were to extract in 400 ml methanol for two weeks at room temperature. For antimicrobial susceptibility testing of medical plants extract blank discs with 6 mm diameter disc diffusion method was used. We determined that all Escherichia coli strains isolated from milk of conventional breeding of cows were resistant to ampicillin and chloramphenicol. We determined that all tested ampicillin and chloramphenicol resistant E. coli strains isolated from conventional breeding of cow showed susceptibility to all used medical plants extracts. In difference, we determined that antibiotic susceptible E. coli strains isolated from ecological breeding of Lipicanmare were susceptible to Tussilagofarfara extract only. From these results we could be conclude some observations, which could be important step in treatment of bacterial infections caused by antibiotic resistant bacteria and it could be important knowledge for treatment of livestock in conventional breeding. Of course, to confirm our analysis further studies are needed.

The aim of our study was the identification of red wine microbiota during the fermentation process using a classical microbiological method and real-time PCR. The changes in different groups of microorganisms were monitored in total counts of bacteria, Lactobacillus cells and Acetobacter cells. Microbiological parameters were observed during the current collection and processing of wine in 2012. Samples were taken during the fermentation process in wine enterprises and were storaged with different conditions. During this period were examined 4 bottles of wine berween Cabernet Sauvignon and Frankovka modra. The total counts of bacteria ranged from 4.98±0.08 in the wine Cabernet Sauvignon at 4 °C of storage to 5.63±0.13 log CFU.ml-1 in the wine Cabernet Sauvignon at 25 °C of storage. The number of lactobacilli ranged from 2.18±0.10 in the Cabernet Sauvignon at 4 °C to 2.49±0.04 log CFU.ml-1 in the Frankovka modra wine at 25 °C of storage and the number of Acetobacter cells ranged from 4.21±0.04 in the Cabernet Sauvignon at 4 °C of storage to 4.52±0.15 log CFU.ml-1 in Cabernet Sauvignon at 25 °C of storage. The presence and sensitivity of Gram-positive and Gram-negative bacterial species Lactobacillus acidophilus, Lactobacillus crispatus, Lactobacillus salivarius, Acetobacter aceti, Acetobacter pasteurianus and Acetobacter orleaniensis were detected using Real time PCR.

The present study aimed to characterize twenty four honeys available in the Slovakapiarist inrespect to their floral origins (rape, lime, honeydew honey), physicochemical and microbial parameters. Moisture content, ash, acidity and electrical conductivity were the parameters analyzed in each honey sample. Total bacteria count and coliform bacteria were the microbial contaminants of interest studied. Concerning the physicochemical parameters, all honey samples were found to meet European Legislation (EC Directive 2001/110) for all parameters. Microbiologically,the commercial quality was considered good and all samples showed to be negative in respect to safetyparameters.

The aim of this study was to follow the contamination of food with Listeria monocytogenes by using Step One real time polymerase chain reaction (PCR). We used the PrepSEQ Rapid Spin Sample Preparation Kit for isolation of DNA and SensiFAST SYBR Hi-ROX Kit for the real-time PCR performance. In 24 samples of food of animal origin without incubation were detected strains of Listeria monocytogenes in 15 samples (swabs). Nine samples were negative. Our results indicated that the real-time PCR assay developed in this study could sensitively detect Listeria monocytogenes in food of animal origin without incubation. This could prevent infection caused by Listeria monocytogenes, and also could benefit food manufacturing companies by extending their product’s shelf-life as well as saving the cost of warehousing their food products while awaiting pathogen testing results. The rapid real-time PCR-based method performed very well compared to the conventional method. It is a fast, simple, specific and sensitive way to detect nucleic acids, which could be used in clinical diagnostic tests in the future.

In this study, the antibacterial and cytotoxic activities of isolated compounds from the roots of Onosma visianii were investigated. By using different chromatographic techniques and appropriate spectroscopic methods, the seven naphthoquinones were described: deoxyshikonin (1), isobutyrylshikonin (2), α-methylbutyrylshikonin (3), acetylshikonin (4), β-hydroxyisovalerylshikonin (5), 5,8-O-dimethyl isobutyrylshikonin (6) and 5,8-O-dimethyl deoxyshikonin (7). Among the tested compounds, 3 and 4 exhibited the highest antibacterial activities toward all tested bacterial species (MIC50 and MIC90 for gram positive bacteria: 6.40 μg/mL-12.79 μg/mL and 6.82 μg/mL-13.60 μg/mL, respectively; for gram negative bacteria: 4.27 μg/mL-8.53 μg/mL and 4.77 μg/mL-9.54 μg/mL, respectively). Also, naphthoquinones 3 and 4 exhibited strong cytotoxic activity against MDA-MB-231 cells (IC50 values 86.0 μg/mL and 80.2 μg/mL, respectively), while compounds 1, 3, 4 and 5 significantly decreased viability of HCT116 cells (IC50 values of 97.8 μg/mL, 15.2 μg/mL, 24.6 μg/mL and 30.9 μg/mL, respectively). Our results indicated that all tested naphthoquinone pigments are potential candidates for clinical uses as antibacterial and cytotoxic agents., EXCLI Journal; 16:Doc73; ISSN 1611-2156

The aim of this study was to determine the antibiotic susceptibility of lactobacilli strains isolated from milk and milk products from middle Slovakia. The 42 samples of milk and milk products were collected from sheep farming from middle Slovakia. MRS agar was used for this cultivation. It was done at 37 °C during 36-48 hours in CO2 box with 10 % CO2. Identification of lactobacilli strains was done by Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry with Biotyper software – MALDI TOF MS Biotyper. Four anitibiotics M.I.C. We used four anitibiotics M.I.C. evaluators strips for antibiotic susceptibility testing. These antibiotics were used in this experiment: erythromycin (E 256 – 0.015 µg/ml), ampicillin (AMP 256 – 0.015 µg/ml), gentamycin (CN 256 – 0.015 µg/ml) and tetracycline (TE 256 – 0.015 µg/ml). We isolated 42 lactobacilli strains and identified them as Lactobacillus plantarum and Lactobacillus spp. We isolated 7 strains of Lactobacillus plantarum and 35 isolates were Lactobacillus spp. From the seven isolates of Lactobacillus plantarum 3 isolates were resistant to ampicillin (MIC 16 µg/ml in 2 isolates and MIC 12 µg/ml in one isolate) and one resistant to tetracycline (MIC 16 µg/ml). From 35 isolates of Lactobacillus spp. 9 isolates were resistant to erytromycin (32 µg/ml), 10 isolates resistant to ampicillin (MIC 16 µg/ml in 4 isolates, MIC 12 µg/ml in 5 isolates and MIC 4 µg/ml in one isolate), 5 isolates resistant to tetracycline (16 µg/ml). Resistance to gentamycin was not detected. Lactobacilli isolated from milk and milk products were resistant to erytromycin (resistanece was 21.42 %), ampicillin (resistance was 30.95 %) and tetracycline (resistance was 14.28 %) and were sensitive in 100 % to gentamycin.

In the experiment, we used propolis extract (200 mg.kg-1) in feed mixture during 40 days of feeding (experimental group) of Ross 308 chickens. Then, we evaluated technological properties of poultry meat stored by freezing at -18 °C for 3 months. In the breast muscle, pH was 6.04 for control group and significantly lower (P≤0.01) 5.86 for experimental group but without negative influence on meat quality. In the thigh muscle, pH values between the groups (control – 6.12; experimental – 6.15) were not significant (P≥0.05). In the breast muscle, colour of meat was 26.17% R (control group) and 25.85% R (experimental group). Paler colour of meat was insignificantly recorded in control group. In thigh muscle, we found (P≥0.05) a higher value 18.78% R in experimental group compared with control group (18.57% R). In the breast muscle, shear force was slightly higher (P≥0.05) in experimental group (1.59 kg.cm-2) compared with control group (1.58 kg.cm-2). In the thigh muscle, higher value of shear force (P≥0.05) was recorded in control group (1.35 kg.cm-2) compared with experimental group (1.29 kg.cm-2). Baking losses were higher by 1.19% (P≥0.05) in experimental group (30.59%) compared with control group (29.40%). Results of the experiment confirm that propolis extract (200 mg.kg-1) can be applied in nutrition of Ross 308 chickens, because it has not negative effects and has not significant influence on selected technological indicators of poultry meat quality.