The main aim of the study was to investigate the chemical composition, antioxidant, antimicrobial, and antibiofilm activity of
essential oil (CAEO). The biofilm profile of
and
were assessed using the ...mass spectrometry MALDI-TOF MS Biotyper and the antibiofilm activity of
(CAEO) was studied on wood and glass surfaces. A semi-quantitative composition using a modified version was applied for the CAEO characterization. The antioxidant activity of CAEO was determined using the DPPH method. The antimicrobial activity was analyzed by disc diffusion for two biofilm producing bacteria, while the vapor phase was used for three penicillia. The antibiofilm activity was observed with the agar microdilution method. The molecular differences of biofilm formation on different days were analyzed, and the genetic similarity was studied with dendrograms constructed from MSP spectra to illustrate the grouping profiles of
and
. A differentiated branch was obtained for early growth variants of
for planktonic cells and all experimental groups. The time span can be reported for the grouping pattern of
preferentially when comparing to the media matrix, but without clear differences among variants. Furthermore, the minimum inhibitory doses of the CAEO were investigated against microscopic fungi. The results showed that CAEO was most active against
, in the vapor phase, on bread and carrot in situ.
Full text
Available for:
IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
This study focused on the identification of bacterial profiles of semen in normozoospermic men and their possible involvement in changes to the sperm structural integrity and functional activity. ...Furthermore, we studied possible fluctuations of selected cytokines, oxidative markers, and antibacterial proteins as a result of bacterial presence in the ejaculate. Sperm motility was assessed with computer-assisted sperm analysis, while sperm apoptosis, necrosis and acrosome integrity were examined with fluorescent methods. Reactive oxygen species (ROS) generation was quantified via luminometry, sperm DNA fragmentation was evaluated using the TUNEL protocol and chromatin-dispersion test, while the JC-1 assay was applied to evaluate the mitochondrial membrane potential. Cytokine levels were quantified with the biochip assay, whilst selected antibacterial proteins were quantified using the ELISA method. The predominant species identified by the matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry were Staphylococcus hominis, Staphylococcus capitis and Micrococcus luteus. The results revealed that the sperm quality decreased proportionally to the increasing bacterial load and occurrence of conditionally pathogenic bacteria, including Enterococcus faecalis, Staphylococcus aureus and Escherichia coli. Antimicrobial susceptibility tests revealed a substantial resistance of randomly selected bacterial strains to ampicillin, vancomycin, tobramycin, and tetracycline. Furthermore, an increased bacterial quantity in semen was accompanied by elevated levels of pro-inflammatory cytokines, including interleukin-1, interleukin-2, interleukin-6, tumor necrosis factor alpha as well as ROS overproduction and lipid peroxidation of the sperm membranes. Our results suggest that semen quality may be notably affected by the bacterial quantity as well as quality. It seems that bacteriospermia may be associated with inflammatory processes, oxidative stress, sperm structural deterioration, and a subsequent risk for the development of subfertility, even in normozoospermic males.
Full text
Available for:
IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Natural products of plant origin, which include essential oils (EO) could be used as a growth inhibitor of pathogenic and spoilage microflora in food. The objective of this study was to determine the ...antibacterial and antioxidant activity of 21 EO against 10 Pseudomonas species isolated from freshwater fish. The chemical composition of EO was determined by gas chromatography/mass spectrometry. The disc diffusion method and detection of minimum inhibitory concentration (MIC) were used for the determination of the antimicrobial activity. All the EO tested exhibited antimicrobial activity, however, Cinnamomum zeylanicum EO was the most effective against Pseudomonas spp. both according to the disc diffusion and MIC methods. The EOs of Cymbopogon nardus, Origanum vulgare, Foeniculum vulgare and Thymus serpyllum showed the highest antioxidant activity of 93.86μg, 83.47μg, 76.74μg and 74.28μgTEAC/mL. Application of EO could be an effective tool for inhibition of growth of Pseudomonas spp. on fish.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
“Bryndza” cheese is an important Slovak traditional regional product. New knowledge on the role of microorganisms involved the “Bryndza” ripening process may provide valuable data on its quality and ...safety. In our study, the “Bryndza” made from pasteurized ewes milk was studied towards total count of bacteria, coliforms bacteria, enterococci, lactic acid bacteria, and microscopic filamentous fungi. All those groups of microbiota were detected using classical microbiological methods and identified using mass spectrometry. A total of 3,758 isolates were identified with score higher than 2.00. Altogether, 13 families, 24 genus, and 44 species of microbiota were identified in Slovak cheese “Bryndza.” The most often isolated species were yeasts
and
and the lactic acid bacteria
subsp.
The aim of the present study was to evaluate the microbiological quality of rainbow trout meat treated with essential oils (EOs from Citrus limon and Cinnamomum camphora) at concentrations of 0.5% ...and 1.0% in combination with vacuum packaging during storage. The composition of the EOs were analyzed by gas chromatography coupled with mass spectrometry, and total viable counts (TVCs), coliform bacteria (CB), and lactic acid bacteria (LAB) were determined on the zeroth, first, third, fifth, and seventh days of storage at 4 °C. Individual species of isolated microorganisms were identified using a MALDI-TOF MS Biotyper. The results show that the major components of the EOs were linalool (98.1%) in C. camphora and α-limonene in C. limon. The highest number of TVCs and CB were 4.49 log CFU/g and 2.65 log CFU/g in aerobically packed samples at the seventh day. The lowest TVCs were those of samples treated with 1% C. camphora EO. For CB the most effective treatment was 1% lemon EO. LAB were only detected in a few samples, and were never present in aerobically packed samples; the highest number of LAB was 1.39 log CFU/g in samples treated with 1% lemon EO at day seven. The most commonly isolated coliform bacteria were Hafnia alvei, Serratia fonticola, Serratia proteamaculans, Pantoea agglomerans, and Yersinia ruckeri. Lactobacillus sakei, Staphylococcus hominis, and Carnobacterium maltaromaticum were the most frequently isolated bacteria from lactic acid bacteria. In conclusion, C. camphora EO at a concentration of 1% showed the highest antimicrobial activity.
Full text
Available for:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
Bryndza cheese is a traditional Slovakian product. In this research, we have investigated whether it would be possible to freeze bryndza, store it at a temperature of -18°C, and then thaw and place ...it on the market during the off-production season. The current legislation in Slovakia does not allow this procedure. The freezing process was chosen based on the request of several small food business operators who would like to replace the process of preserving the primary raw material, matured salted ewe’s lump cheese, in barrels due to acrid-sour taste. Bryndza cheese is preferred by consumers due to its unique microbial composition, which is beneficial for their health. Many microorganisms present in bryndza are probiotics. For this reason, we wanted to determine how the microflora in the bryndza cheese changes after freezing. These findings have practical implications for the food industry, particularly for small food business operators, who can potentially adopt freezing to preserve bryndza, thereby extending its shelf life and availability to consumers. Additionally, in many households, people store bryndza in their freezers after purchasing and use it to prepare dishes. Understanding the role of microorganisms in the ripening process and during storage can provide valuable data on Brynzda quality and safety. The present study aimed to analyse the representation of microorganisms in “Bryndza” samples at the beginning of storage and after 6 months of storage at a temperature of -18 °C. A total of 10 samples of “Bryndza” cheese made from pasteurised milk were analysed. Analysis of total viable counts of viable bacteria (TVC), coliform bacteria (CB), lactic acid bacteria (LAB), and microscopic filamentous fungi (MFF) was performed using the plate dilution method. Isolated strains of microorganisms were identified with mass spectrometry MALDI-TOF MS Biotyper. A total of 295 isolates from Bryndza cheese were identified at the start of storage and 220 isolates at the end of storage of samples. The dominant species of microorganisms found in Bryndza cheese were lactic acid bacteria, especially Lactococcus lactis, with 68 isolates and Lactobacillus fermentum, with 41 isolates at the start of storage. The most frequently isolated species were Lactococcus lactis, with 62 isolates, and Limosilactobacillus fermentum, with 33 isolates. Our results show that important lactic acid bacteria were present in the bryndza even after 6 months of freezing, but coliform bacteria were absent. Experimental outputs: TVC: showed no significant decrease (p-value = 0.0137); LAB: No significant decrease in lactic acid bacteria counts post-storage; MFF: Significant decrease in microscopic filamentous fungi post-storage; CB: Qualitative analysis indicates a significant reduction to undetectable levels after storage. Long-term storage of bryndza at -18°C is safe from a microbiological point of view.
This study was designed to investigate chemical and antioxidant properties, as well as the antimicrobial and antibiofilm behaviour of
essential oil (CCEO). MALDI-TOF MS Biotyper mass spectrometry was ...applied to evaluate the biofilms of
and
, while the antibiofilm ability of CCEO was assessed on wooden and glass surfaces. The antimicrobial activity by disc diffusion method, microdilution method, and vapour phase for two biofilm-producing bacteria and three
spp. were used. Antimicrobial and antibiofilm properties were assessed using the agar microdilution protocol. The vapour phase of
and
on bread, carrot, potato, sweet potato, and apple
was studied. Specific molecular variations related to the biofilm formation and genetic analogies were evaluated with MSP spectra dendrograms of
and
profiles were grown on different days. The results of disc diffusion and broth diffusion methods showed that CCEO was strongly effective against all tested microorganisms and the vapour phase method was effective and active against all
spp., but not strongly effective against bacteria in food preservation of food matrices.
Bacteriospermia has become a serious factor affecting sperm quality in swine breeding, this is why antibiotics (ATBs) are a critical component of semen extenders. Due to ever-increasing antimicrobial ...resistance, the aim of this study was to assess the efficiency of selected commercially available semen extenders to prevent a possible bacterial contamination of boar ejaculates. Three Androstar Plus extenders containing different combinations of antibiotics were used to process ejaculates from 30 healthy Duroc breeding boars. Androstar Plus without antibiotics was used as a control. The extended samples were stored at 17 °C for 72 h. Sperm motility, viability, mitochondrial activity, DNA integrity and oxidative profile of each extended sample were assessed following 24 h, 48 h and 72 h. Furthermore, selective media were used to quantify the bacterial load and specific bacterial species were identified with matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry. The results indicate that semen extenders enriched with ATBs ensured a significantly higher preservation of the sperm quality in comparison to the ATB-free control. The total bacterial count was significantly decreased in the extenders supplemented with ATBs (p < 0.001), however gentamycin alone was not effective enough against Gram-positive bacteria, while a few colonies of Enterococcus hirae, Bacillus subtilis and Corynebacterium spp. were present in the samples extended in the presence of a triple combination of ATBs. In conclusion, we may suggest that semen extenders enriched in antibiotics were not able to fully eliminate the bacteria present in the studied samples. Furthermore, selection of suitable antibiotics for semen extension should be accompanied by adequate hygiene standards during the collection and handling of boar ejaculates.
Full text
Available for:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
The present study aimed to evaluate deer meat microbiological quality when treated with essential oil (EO) from Litsea cubeba (dissolved in rapeseed oil at concentrations 0.5 and 1%), in combination ...with vacuum packaging during 20 days of storage of meat at 4 °C. Total viable counts (TVC), coliforms bacteria (CB), lactic acid bacteria (LAB) and Pseudomonas spp. were analysed at day 0, 1, 5, 10, 15 and 20. MALDI-TOF MS Biotyper technology was applied to identify microorganisms isolated from meat. The highest number of TVC at the end of the experiment was 5.50 log CFU/g in the aerobically packaged control group and the lowest number of TVC was 5.17 log CFU/g in the samples treated with 1.0% Litsea cubeba EO. CB were not detected in the samples treated with 1.0% Litsea cubeba EO during the entire storage period. Bacteria of the genus Pseudomonas were detected only in the aerobically and vacuum packaged control group. The highest number of LAB was 2.06 log CFU/g in the aerobic control group, and the lowest number of LAB was 2.01 log CFU/g in the samples treated with 1.0% Litsea cubeba EO on day 20. The most frequently isolated bacteria from deer meat were Pseudomonas ludensis, Pseudomonas corrugata, Pseudomonas fragi, Bacillus cereus, Staphylococcus epidermidis and Sphingomonas leidyi.
Full text
Available for:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
The present study aimed to evaluate the microbial quality of minced pork treated with fresh garlic, dried garlic, and garlic oil in combination with vacuum packing. The growth of Total Viable Counts ...(TVC), Coliform Bacteria (CB), and Pseudomonas spp. were evaluated. The microbiological analyses were performed by the plate dilution method. The average value of TVC was 8.45 log CFU.g-1 in aerobically packed samples, 5.59 log CFU.g-1 in samples treated with garlic oil, 5.36 log CFU.g-1 in vacuum packed samples, and samples treated with dried garlic, and 4.98 log CFU.g-1 in samples treated with fresh garlic on 8th day of storage. The number of TVC was significantly lower in samples treated with fresh garlic compared to samples treated with dried garlic and garlic oil on the 8th day of storage (p <0.05). The average value of CB was 4.13 log CFU.g-1 in aerobically packed samples, 1.82 log CFU.g-1 in samples treated with garlic oil, the value of CB in vacuum packed samples, in samples treated with fresh garlic and also with dried garlic was lower than 1.00 log CFU.g-1 on 8th day of storage. The number of CB was significantly higher in aerobically packed samples and samples treated with garlic oil compared to vacuum-packed samples, samples treated with fresh garlic and dried garlic on the 8th day of storage (p <0.05). The average number of Pseudomonas spp. was 2.45 in aerobically packed samples, count of Pseudomonas spp. was lower than 1.00 log CFU.g-1 in vacuum packed samples and in the sample with garlic on the 8th day of storage. The number of Pseudomonas spp. was significantly higher in aerobically packed samples in comparison with vacuum-packed samples, samples with fresh garlic, dried garlic, and garlic oil (p <0.05).
PDF
