Antibacterial activity of oregano and sage plant extracts against decarboxylase-positive enterococci isolated from rabbit meat

The effect of plant extracts (sage, oregano) against decarboxylase-positive enterococci from rabbit back limb meat  was reported in this study. Oregano plant extract inhibited the growth of all 34 tested enterococci (the inhibitory zones: 12 to 45 mm). The growth of the majority of strains  (n=23) was inhibited by oregano plant extract (the high size inhibitory zones (higher than 25 mm). The growth of 11 strains  was inhibited by oregano extract reaching medium size inhibitory zones (10 to 25mm). The most sensitive strain to oregano extract was E. faecium M7bA (45 mm). Sage extract was less active against tested enterococci (n=16)  reaching lower inhibitory zones (up to 10 mm)

Studium deformačních procesů v slitinách Mg-Gd

Název práce: Studium deformačních procesů v slitinách Mg-Gd Autor: Andrea Szabóová Katedra / Ústav: Katedra fyziky materiálů Vedoucí bakalářské práce: doc. RNDr. Kristián Mathis, DrSc. Abstrakt: Předložená práce se zabývá studiem deformačního chování binárních slitin hořčík-gadolinium v závislosti na koncentraci Gd a na teplotě deformace. Extrudované vzorky vykazovaly poměrně silnou výchozí texturu. Tlakové deformační zkoušky byly prováděny při pokojové teplotě a při 200řC. Souběžně s deformací byla zaznamenávána i akustická emise, kterou jsme analyzovali s pokročilými statistickými metodami. Kombinací těchto dvou experimentálních metod jsme ukázali, že v počátečním stádiu deformace dominuje dvojčatění, ale v pozdější fázi plastická deformace proběhne převážně nebazálním kluzem. S vyšším obsahem Gd klesá velikost dvojčat, v důsledku snížení mobility dvojčatových hranic příměsovými atomy. Při vyšších deformačních teplotách dvojčatění bylo usnadněno tepelnou aktivací. Závěry byly ověřené kombinací optické světelné a skenovací elektronové mikroskopie. Klíčová slova: hořčíková slitina, deformační zkoušky, akustická emise, mikroskopieTitle: Investigation of deformation mechanisms in Mg-Gd alloys Author: Andrea Szabóová Department: Department of Physics of Materials Supervisor: doc. RNDr. Kristián Mathis, DrSc. Abstract: In the present work, the deformation behavior of magnesium-gadolinium binary alloys was investigated. Dependence on the concentration of Gd and deformation temperatures was studied. Extruded samples had relatively strong initial texture. Compression tests were done at room temperature and 200řC. Simultaneously with deformation acoustic emission was recorded. Data from acoustic emission was analyzed with advanced statistical methods. Results of the combination of these two experimental methods indicated that at the beginning of the deformation twinning is the dominant mechanism. In the following stage of plastic deformation non-basal slip systems became the governing deformation mechanism. With higher content of Gd the size of twins decreases as a result of the decreased mobility of twin boundaries caused by solute atoms. At higher temperatures twinning activity was increasing. In addition, results were confirmed by optical light and scanning electron microscopy. Keywords: magnesium alloy, deformation tests, acoustic emission, microscopyKatedra fyziky materiálůDepartment of Physics of MaterialsMatematicko-fyzikální fakultaFaculty of Mathematics and Physic

Studium dynamiky deformačních procesů ve slitinách Mg-RE pomocí in-situ experimentálních metod

Předložená práce se zabývá studiem dynamiky deformačních procesů binárních slitin Mg-Gd pomocí in-situ experimentálních metod v závislosti na koncentraci Gd. Zkoumané lité slitiny jsou charakterizované náhodnou texturou. Tlakové zkoušky byly provedené se souběžným záznamem akustické emise, ze kterého byla následně pomocí pokročilé analýzy určená časová závislost dominantních deformačních mechanismů. Měření vysokorychlostní kamerou umožnila studium dynamiky dvojčatění, včetně vyhodnocení rychlosti propagace dvojčat v závislosti na koncentraci Gd. Deformační zkoušky byly opakovány v komoře řádkovacího elektronového mikroskopu (in-situ SEM) za současného pozorování mikrostruktury pomocí sekundárných elektronů a zpětně odrážených elektronů (EBSD) v jednotlivých stádiích deformace. Cílem těchto měření bylo identifikovat aktivní skluzové systémy a určit vývoj podílu dvojčat v průběhu deformace. Klíčová slova: hořčíková slitina, deformační zkoušky, akustická emise, vysokorychlostní kamera, elektronová mikroskopie, dvojčatěníIn this present work, the dynamics of deformation mechanisms activated in binary magnesium-gadolinium alloys with respect to amount of Gd were investigated with in-situ experimental methods. Cast alloys are characterized by random texture. Compression test were done at room temperature with simultaneous record of acoustic emission response. The acoustic emission signal was subsequently analysed using advanced clustering method providing information about the dominant deformation mechanisms. High speed camera was used to study the dynamics of twinning, including estimation of the velocity of twin propagation with respect to Gd concentration. The deformation tests were repeated in a chamber of scanning electron microscope (in-situ SEM) with concurrent following the microstructure development using secondary electrons and electron back-scattered diffraction (EBSD) in different stages of the deformation. Main goal of this measurements was to identify active slip systems and the progress of twin volume fraction during deformation. Keywords: magnesium alloy, deformation tests, acoustic emission, high-speed camera, electron microscopy, twinningDepartment of Physics of MaterialsKatedra fyziky materiálůMatematicko-fyzikální fakultaFaculty of Mathematics and Physic

GENERATION OF A SET OF KEY TERMS CHARACTERISING TEXT DOCUMENTS

The presented paper describes statistical methods (information gain, mutual X^2 statistics, and TF-IDF method) for key words generation from a text document collection. These key words should characterise the content of text documents and can be used to retrieve relevant documents from a document collection. Term relations were detected on the base of conditional probability of term occurrences. The focus is on the detection of those words, which occur together very often. Thus, key words, which consist from two terms were generated additionally. Several tests were carried out using the 20 News Groups collection of text documents

Decarboxylase-positive Enterococcus faecium strains isolated from rabbit meat and their sensitivity to enterocins

Background: The objective of the study was to determine sensitivity of Enterococcus faecium strains from rabbit meat to enterocins. Results: Twenty-five decarboxylase-positive strains (from rabbit meat) allotted to the species E. faecium by genotypization and by MALDI TOF MS spectrometry identification (evaluation score value range 2.104–2.359; in the range for highly probable species identification-score value 2.300–3.000 and secure probable species identification/probable species identification-2.000–2.299) were studied. Seventeen strains were gelatinase positive. Although they did not produce histamine (HIS), spermidine, and spermine, they produce at least one among seven tested biogenic amines (BAs) in small amounts (2–10 mg/L) or up to very high amounts (>1000 mg/L). Putrescine was produced by two strains. These decarboxylase-positive strains were sensitive to enterocins (Ents). All strains were sensitive to Ent 2019 and Ent 55 (inhibitory activity from 200 to 819 200 AU/mL). Twenty-two strains were inhibited by Ent A(P) and Ent 4231; 20 strains were sensitive to Ent M. Conclusion: Our results have spread the basic knowledge related to inhibitory spectrum of enterocins showing sensitivity of decarboxylase-positive strains to enterocins. Protective possibilities of enterocins in meat processing were also indicated. © 2016 The Authors. Food Science & Nutrition published by Wiley Periodicals, Inc.Slovak Scientific Agency VEGA [2/0004/14]; Slovak Research and Development Agency [SK-HU-0006-08

Microbial status and quality of rabbit meat after rabbits feed supplementation with phyto-additives

Nowdays, there is an increasing  interest in public health issue due to consumption of healthy and nutritive food, e.i. rich in proteins, low in cholesterol and lipid contents. The aim of this study was to examine if oregano, sage and Eleutherococcus senticosus extracts, commercial Xtract as well can influence microbial status of rabbit meat after their supplementation of rabbit feed. Reduction of enterococci, coagulase-negative staphylococci and Staphylococcus aureus after feed supplementation by the sage and oregano was more detectable at the end of the experiment (at day 42) than after their application (at day 21). In animals with Xtract addition, antibacterial effect has been noted already at day 21. Our in vivo results confirmed in vitro antibacterial effect of the tested extracts and showed that maintaining of rabbit meat quality by plant extracts is very promising

Comparative Analysis Reveals Changes in Some Seed Properties in Amaranth Mutant Variety ‘Zobor’ (A. hypochondriacus × A. hybridus)

The aim of our long-term research program is to improve the quality and quantity of amaranth production through mutation breeding using γ-radiation. In this paper, we present the characterization of the new variety ‘Zobor’ of A. hypochondriacus × A. hybridus developed by radiation-induced mutagenesis of hybrid K-433. Multiyear phenotypic characterization of an important yield parameter (1000-seed weight) showed that the studied mutant variety ‘Zobor’ has an advantage in seed weight over the nonirradiated control seeds of K-433 with predictable performance of this yield trait. ‘Zobor’ exhibited changes in seed morphometric parameters, starch particle size, and pasting properties with no change in amylose content and swelling power. Moreover, the seeds of ‘Zobor’ showed the significantly highest folate content among selected amaranth varieties. The mutant variety could, therefore, be interesting for the development of functional foods and as a low-management crop, attractive for cultivation in Europe

Comparative Analysis Reveals Changes in Some Seed Properties in Amaranth Mutant Variety ‘Zobor’ (A. hypochondriacus × A. hybridus)

The aim of our long-term research program is to improve the quality and quantity of amaranth production through mutation breeding using γ-radiation. In this paper, we present the characterization of the new variety ‘Zobor’ of A. hypochondriacus × A. hybridus developed by radiation-induced mutagenesis of hybrid K-433. Multiyear phenotypic characterization of an important yield parameter (1000-seed weight) showed that the studied mutant variety ‘Zobor’ has an advantage in seed weight over the nonirradiated control seeds of K-433 with predictable performance of this yield trait. ‘Zobor’ exhibited changes in seed morphometric parameters, starch particle size, and pasting properties with no change in amylose content and swelling power. Moreover, the seeds of ‘Zobor’ showed the significantly highest folate content among selected amaranth varieties. The mutant variety could, therefore, be interesting for the development of functional foods and as a low-management crop, attractive for cultivation in Europe

Bacteriocin-producing strain lactiplantibacillus plantarum LP17L/1 isolated from traditional stored Ewe’s milk cheese and its beneficial potential

Research Areas: Food Science & TechnologyStored ewe’s milk lump cheese is a local product that can be a source of autochthonous beneficial microbiota, especially lactic acid bacteria. The aim of this study was to show the antimicrobial potential of Lactiplantibacillus plantarum LP17L/1 isolated from stored ewe’s milk lump cheese. Lpb. plantarum LP17L/1 is a non-hemolytic, non-biofilm-forming strain, susceptible to antibiotics. It contains genes for 10 bacteriocins—plantaricins and exerted active bacteriocin with in vitro antistaphylococcal and anti-listerial effect. It does not produce damaging enzymes, but it produces β-galactosidase. It also sufficiently survives in Balb/c mice without side effects which indicate its safety. Moreover, a reduction in coliforms in mice jejunum was noted. LP17L/1 is supposed to be a promising additive for Slovak local dairy products.info:eu-repo/semantics/publishedVersio

Enterococci from pannon white rabbits: detection, identification, biofilm and screening for virulence factors

[EN] Properties of enterococci isolated from the Hungarian breed Pannon White were studied to spread knowledge regarding the properties of microbiota in rabbits from the basic research standpoint and to select a beneficial candidate for application in husbandry. Faeces from 113 Pannon White rabbits (mostly maternal line and some paternal line) were collected. They were sampled from rabbits varying in age and sex (82 kits, 6 does, 6 bucks, 19 adult rabbits), which were aged 2 wk (14 suckling rabbits), 6 and 8 wk (68 weaning and post-weaning rabbits), adult rabbits (31, one year). Faecal mixtures were sampled into sterile packs with faeces from 5-6 animals in each. The total count of enterococci from these Pannon White rabbits reached, on av. 5.28±0.29 colony forming units/g (log10). Among the 19 enterococci, 14 E. faecalis and 5 E. faecium were detected using 3 identification methods. The enterococci were mostly resistant to antibiotics. They were non-haemolytic, Dnase and urease negative. They did not form biofilm. They were free of the hylEfm gene and IS16 genes; the most frequently detected genes were gelE, efaAfm, efaAfs. Based on these results, E. faecium EF9a was selected for further analysis.The results achieved were financially supported by the bilateral Slovak-Hungarian project APVV:SK-HU-0006-08 and partially by the projects Probiotech ITMS 26220220204 and Vega 2/0006/2017.Lauková, A.; Strompfová, V.; Szabóová, R.; Bónai, A.; Matics, Z.; Kovács, M.; Pogány Simonová, M. (2019). Enterococci from pannon white rabbits: detection, identification, biofilm and screening for virulence factors. World Rabbit Science. 27(1):31-39. https://doi.org/10.4995/wrs.2019.10875SWORD3139271Bagóne Vántus V., Dalle Zotte A., Cullere M., Bónai A., Dal Bosco A., Szendro Zs., Tornyos G., Pósa R., Bóta B., Kovács M., Zsolnai A. 2018. 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