Łucja Łaniewska-Trokenheim
University of Warmia and Mazury in Olsztyn
Network
Latest external collaboration on country level. Dive into details by clicking on the dots.
Publication
Featured researches published by Łucja Łaniewska-Trokenheim.
Food Microbiology | 2015
Wioleta Chajęcka-Wierzchowska; Anna Zadernowska; Beata Nalepa; Magda Sierpińska; Łucja Łaniewska-Trokenheim
The aim of this work was to study the pheno- and genotypical antimicrobial resistance profile of coagulase negative staphylococci (CoNS) isolated from 146 ready-to-eat food of animal origin (cheeses, cured meats, sausages, smoked fishes). 58 strains were isolated, they were classified as Staphylococcus xylosus (n = 29), Staphylococcus epidermidis (n = 16); Staphylococcus lentus (n = 7); Staphylococcus saprophyticus (n = 4); Staphylococcus hyicus (n = 1) and Staphylococcus simulans (n = 1) by phenotypic and genotypic methods. Isolates were tested for resistance to erythromycin, clindamycin, gentamicin, cefoxitin, norfloxacin, ciprofloxacin, tetracycline, tigecycline, rifampicin, nitrofurantoin, linezolid, trimetoprim, sulphamethoxazole/trimethoprim, chloramphenicol, quinupristin/dalfopristin by the disk diffusion method. PCR was used for the detection of antibiotic resistance genes encoding: methicillin resistance--mecA; macrolide resistance--erm(A), erm(B), erm(C), mrs(A/B); efflux proteins tet(K) and tet(L) and ribosomal protection proteins tet(M). For all the tet(M)-positive isolates the presence of conjugative transposons of the Tn916-Tn1545 family was determined. Most of the isolates were resistant to cefoxitin (41.3%) followed by clindamycin (36.2%), tigecycline (24.1%), rifampicin (17.2%) and erythromycin (13.8%). 32.2% staphylococcal isolates were multidrug resistant (MDR). All methicillin resistant staphylococci harboured mecA gene. Isolates, phenotypic resistant to tetracycline, harboured at least one tetracycline resistance determinant on which tet(M) was most frequent. All of the isolates positive for tet(M) genes were positive for the Tn916-Tn1545 -like integrase family gene. In the erythromycin-resistant isolates, the macrolide resistance genes erm(C) or msr(A/B) were present. Although coagulase-negative staphylococci are not classical food poisoning bacteria, its presence in food could be of public health significance due to the possible spread of antibiotic resistance.
Food Reviews International | 2014
Anna Zadernowska; Wioleta Chajęcka-Wierzchowska; Łucja Łaniewska-Trokenheim
Yersinia enterocolitica is listed in the annual reports of the European Food Safety Authority (EFSA) as the third-most-common enteropathogen. The highly pathogenic Y. enterocolitica bioserotype 1B/O8 is geographically limited to Northern America, although it has also emerged in Japan and Europe. Furthermore, the number of reports on the pathogenicity of serotype 1A (so far regarded as nonpathogenic) has been increasing. Humans are most often infected by consuming raw or inadequately thermally processed pork or milk as well as vegetable products and ready-to-eat meals. Identification of these bacteria in food presents considerable methodological problems.
Journal of Microbiology | 2010
Łucja Łaniewska-Trokenheim; Magdalena Olszewska; Marta Mikš-Krajnik; Anna Zadernowska
The focus of this study was to monitor the survival of populations and the volatile compound profiles of selected Lactobacillus strains during long-term incubation in milk. The enumeration of cells was determined by both the Direct Epifluorescent Filter Technique using carboxyfluorescein diacetate (CFDA) staining and the plate method. Volatile compounds were analysed by the gas-chromatography technique. All strains exhibited good survival in cultured milks, but Lactobacillus crispatus L800 was the only strain with comparable growth and viability in milk, assessed by plate and epifluorescence methods. The significant differences in cell numbers between plate and microscopic counts were obtained for L. acidophilus strains. The investigated strains exhibited different metabolic profiles. Depending on the strain used, 3 to 8 compounds were produced. The strains produced significantly higher concentrations of acetic acid, compared to other volatiles. Lactobacillus strains differed from one another in number and contents of the volatile compounds.
Microbiological Research | 2016
Magdalena Olszewska; Aleksandra Maria Kocot; Anna Nynca; Łucja Łaniewska-Trokenheim
pH stress is recognized as an important feature for Lactobacillus in relation to lifestyle and commercial utility. Hence, this study aims to investigate the cell function of Lactobacilli cells subjected to pHs between 7.0 and 2.0. For this purpose, the Lactobacilli isolates of vegetable origin were first hybridized with fluorescent oligonucleotide rRNA probes for detecting Lactobacillus species. Then, cells were exposed to pH stress and labelled with fluorescent probes, carboxyfluorescein diacetate (CFDA) and propidium iodine (PI), which provided the insight into esterase activity and membrane integrity of cells. Among isolates, fluorescence in situ hybridization (FISH) enabled us to specifically detect L. plantarum and L. brevis. Interestingly, FCM analysis revealed that at pHs between 7.0 and 4.0 the cell membrane was intact, while after the exposure at pH 3.0, and 2.0 became perturbed or impaired. Finally, L. brevis and L. plantarum differed from each other in fluorescence labeling behaviour and culturability. However, the results showed that the same standard protocol for labeling enables discrimination of subpopulations of tested species. Depending on the species, the substantial culturability loss was observed at pH 3.0 and 2.0. These results suggest that the taxonomic and physiological fluorescent probes could be suitable for in situ detection of specific bacteria and rapid assessment of the physiological status of cells.
Czech Journal of Food Sciences | 2016
Magdalena Olszewska; Aleksandra Maria Kocot; Aleksandra Stanowicka; Łucja Łaniewska-Trokenheim
Olszewska M.A., Kocot A.M., Stanowicka A., Laniewska-Trokenheim Ł. (2016): Biofilm formation by Pseudomonas aeruginosa and disinfectant susceptibility of planktonic and biofilm cells. Czech J. Food Sci., 34. Epifluorescence microscopy (EFM) was used to study the biofilm formation of Pseudomonas aeruginosa after 6, 24, 30, 48, 54, 72, 78, and 96 h growth in a chamber slide system. For this purpose, the biofilm was stained with the Live/Dead BacLight, wherein live and dead cells were visualised based on the cell membrane integrity. With the use of EFM we described 8of 9-stage biofilm characteristics after 78 h of growth, since the majority of microscopic fields were fully covered with attached cells. However, the 96-h growth resulted in the cell detachment and revealed 30% of dead cells of all those cells that remained on the surface. The susceptibility testing of planktonic and biofilm cells to two disinfectants, chlorine-based and quaternary ammonium compound-based, revealed that biofilm cells were more tolerant to a chlorine-based sanitiser than planktonic counterparts. P. aeruginosa was inhibited by lower concentrations of the quaternary ammonium compound-based sanitiser than the chlorine-based sanitiser, which on the other hand was more effective in cell inactivation, as both the MIC/MBC (inhibitory/bactericidal) measurement and the CFDA/PI (carboxyfluorescein diacetate/propidium iodide) staining indicated.
Journal of Biotechnology | 2015
Magdalena Olszewska; Aleksandra Maria Kocot; Łucja Łaniewska-Trokenheim
Changes in pH are significant environmental stresses that may be encountered by lactobacilli during fermentation processes or passage through the gastrointestinal tract. Here, we report the cell response of Lactobacillus spp. isolated from traditionally fermented cabbage subjected to acid/alkaline treatments at pH 2.5, 7.4 and 8.1, which represented pH conditions of the gastrointestinal tract. Among six isolates, four species of Lactobacillus plantarum and two of Lactobacillus brevis were identified by fluorescence in situ hybridization (FISH). The fluorescence-based strategy of combining carboxyfluorescein diacetate (CFDA) and propidium iodine (PI) into a dual-staining assay was used together with epifluorescence microscopy (EFM) and flow cytometry (FCM) for viability assessment. The results showed that the cells maintained esterase activity and membrane integrity at pH 8.1 and 7.4. There was also no loss of culturability as shown by plate counts. In contrast, the majority of 2.5 pH-treated cells had a low extent of esterase activity, and experienced membrane perturbation. For these samples, an extensive loss of culturability was demonstrated. Comparison of the results of an in situ assessment with that of the conventional culturing method has revealed that although part of the stressed population was unable to grow on the growth media, it was deemed viable using a CFDA/PI assay. However, there was no significant change in the cell morphology among pH-treated lactobacilli populations. These analyses are expected to be useful in understanding the cell response of Lactobacillus strains to pH stress and may facilitate future investigation into functional and industrial aspects of this response.
CBU International Conference Proceedings | 2017
Wioleta Chajęcka-Wierzchowska; Anna Zadernowska; Łucja Łaniewska-Trokenheim
The emergence of antibiotic-resistant strains of S. aureus such as methicillin-resistant S. aureus (MRSA) is a worldwide problem. Ready-to-eat (RTE) food which does not need thermal processing before consumption could be a vehicle for the spread of antibiotic-resistant microorganisms. The present study evaluated the molecular genetic characteristics (RAPD) and pheno- and genotypical antimicrobial resistance profile of S. aureus isolated from 75 RTE food samples (sushi, hamburgers, salads). All of the isolates (n=32) were resistant to at least one class of antibiotic tested of which 75% strains were classified as multidrug resistant. Most of the isolates were resistant to cefoxitin (87,5%) followed by clindamycin (78,1%), tigecycline and quinupristin/dalfopristin (53,1%). All methicillin resistant staphylococci harbored mec A gene. Among tetracycline resistance isolates all of them harbored at least one gene: tet (M), tet (L) and/or tet (K) and 78,9% of them were positive for the Tn 916 /Tn 1545 -like integrase family gene. Our results indicated that retail RTE food could be considered an important route for transmission of antibiotic resistant staphylococci harboring multiple antibiotic resistance genes.
Lwt - Food Science and Technology | 2016
Wioleta Chajęcka-Wierzchowska; Anna Zadernowska; Łucja Łaniewska-Trokenheim
Journal of Food Safety | 2012
Wioleta Chajęcka-Wierzchowska; Anna Zadernowska; Lucyna Kłębukowska; Łucja Łaniewska-Trokenheim
Czech Journal of Food Sciences | 2018
Magdalena Olszewska; Bogusław staniewski; Łucja Łaniewska-Trokenheim