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  • Author or Editor: O. Farkas x
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Abstract  

The possibilities of radioanalytical separation by isotopic exchange with metal chelate complexes and metal sulphide precipitates fixed in paper have been examined on the model system203Hg2++58Co2++65Zn2++24Na+.

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The effect of water activity (0.85–0.99 aw) and temperature (20–35 °C) on growth of two potentially toxigenic moulds, Aspergillus niger and Penicillium expansum, were studied. On the basis of the measured colony diameter ComBase DMFit program was used to estimate the lag phase and growth rate. Similar results may provide basis for the risk assessment of fungal growth (and also for the possible mycotoxin contamination) in food and feed plants in the vegetation season due to the climate change (global warming), and also during unfavourable storage conditions.

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Authors: Cs. Mohácsi-Farkas, J. Farkas, L. Mészáros, O. Reichart and É. Andrássy

Abstract  

Thermal stability of vegetative cells of Listeria monocytogenes, Escherichia coli and Lactobacillus plantarum was studied by counting viable fractions and determining DSC curves of their suspensions. DSC curves in the 5–99°C range showed a series of endothermic transitions between 50 and 60°C, where the heat destruction of cells occurred. Heat denaturation of DNA required a higher temperature than cell killing. Thermal death was strongly influenced by the pH, composition and NaCl content of the suspending buffer. A mathematical model developed by us enabled comparison of DSC peak temperatures and temperatures required for loss of viability.

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Authors: E. Paszti-Gere, E. Csibrik-Nemeth, K. Szeker, R. Csizinszky, O. Palocz, O. Farkas and P. Galfi

Recently, there has been a growing interest to replace antibiotics’ administration with the application of probiotics. The aim of our investigations was to reveal the influence of spent culture supernatant of Lactobacillus plantarum 2142 on the response of enterocytes to oxidative stress, and the spent culture supernatant’s ability to protect them from oxidative injury. The experiments were performed on non-carcinogenic porcine epithelial cell line, IPEC-J2 isolated from a neonatal piglet and on human colon adenocarcinoma cell line, Caco-2. The cells cultured on membrane inserts were treated with millimolar hydrogen peroxide solution to provoke oxidative stress. The peroxide-triggered cell response profile was evaluated via determination of change in transepithelial electrical resistance, quantification of extent of cell death by 4’,6-diamidino-2 phenylindole (DAPI) staining and via estimation of proinflammatory cytokine, IL-8 production using ELISA technique. Non-starter lactobacilli supernatant-mediated inhibition of peroxide-triggered upregulation of IL-8 production confirmed the antiinflammatory properties of active metabolites produced by Lactobacillus plantarum 2142 in acute oxidative stress.

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Authors: O. Farkas, Gyöngyi Gyémant, Gréta Hajdú, S. Gonda, P. Parizsa, T. Horgos, Ágnes Mosolygó and G. Vasas

Waterbloom samples of Microcystis aeruginosa and Planktothrix agardhii were collected from a variety of ponds, lakes and reservoirs in Hungary. Samples were tested with matrix-assisted laser desorption/ionization — time-of-flight mass spectrometry (MALDI-TOF MS) to identify the microcystin forms. The concentration of the microcystins was measured with capillary electrophoresis and the toxicity was tested by sinapis test. DNA was extracted from the samples and tested using a range of primers linked to the biosynthesis of microcystin. All of the fourteen collected samples gave positive results for the presence of the mcy genes with PCR products with sizes between of 425 and 955 bp, respectively, indicating the presence of the genes implicated in the production of microcystins. The results showed that a wide range of microcystin (MC) forms were detected in the Microcystis containing samples, among which MC-LR, -RR, and -YR were the most common. The highest MC concentration was 15,701 mg g−1, which was detected in an angling pond. The samples containing Planktothrix agardhii were less toxic, and the most common form in this species was the Asp3-MC-LR.

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Authors: I. Bata-Vidács, A. Lugasi, J. Farkas, O. Németh and P. Fodor
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Authors: Z. Aigner, R. Heinrich, E. Sipos, G. Farkas, A. Ciurba, O. Berkesi and P. Szabó-Révész

Abstract

The compatibility of aceclofenac with various tableting excipients was investigated by means of differential scanning calorimetry (DSC) and Fourier transform infrared spectroscopy (FT-IR). The excipients applied in the direct pressing retard tablets were Carbopol 940, hydroxypropyl-methyl-cellulose, microcrystalline cellulose, Aerosil 200 and magnesium stearate. The ingredients alone and their 1:1 (w/w) binary mixtures were investigated before and after accelerated storage. An interaction was observed only between aceclofenac and magnesium stearate. The DSC and FT-IR examinations indicated formation of the magnesium salt of aceclofenac. For the other mixtures, there was no incompatibility between the components.

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Authors: S. Kondratyuk, L. Lőkös, S. Tschabanenko, M. Haji Moniri, E. Farkas, X. Wang, S.-O. Oh and J.-S. Hur

Seventeen taxa new for science, i.e. Absconditella baegasanensis, Caloplaca hallasanensis, C. subconcilians, Fellhanera chejuensis, F. maritima, Lecania coreana, L. rinodinoides, Lichenostigma heterodermiae, Micarea coreana, Phoma heterodermiae, Protoparmeliopsis chejuensis, Roselliniopsis phaeophysciae, Topelia jasonhurii (all from South Korea); Caloplaca dzhankoiensis (from Ukraine); Protoparmeliopsis pseudogyrophoricum (from China); P. taranii (from Russia); and Seirophora blumii (from several Central Asian countries) are described, compared with closely related taxa, and illustrated.Five new combinations are proposed: Caloplaca subscopularis, Protoparmeliopsis crustaceum, P. gyrophoricum, P. mazatzalensis, and P. pinguis.A total of 64 lichen-forming and lichenicolous fungi are reported here as new for South Korea (i.e. Abrothallus microspermus, Amandinea melaxanthella, Arthonia epiphyscia, Arthothelium ruanum, Aspicilia contorta subsp. hoffmanniana, Biatora globulosa, Brigantiaea purpurata, Caloplaca gordejevii, C. micromera, C. oxneri, C. subscopularis, C. trassii, Candelariella reflexa, Dirina massiliensis, Endococcus cf. verrucosus, Hyperphyscia adglutinata, Hypogymnia austerodes, H. occidentalis, Ionaspis lacustris, Lecanora barkmaniana, Lecanora cf. marginata, L. symmicta, L. varia, Lichenochora obscuroides, Lichenodiplis lecanorae, Lopadium coralloideum, Melaspilea bagliettoana, Menegazzia subsimilis, Micarea denigrata, M. peliocarpa, Myriospora heppii, Myriotrema masonhalei, Ochrolechia frigida, Opegrapha calcarea, O. phaeophysciae, Parmelia subdivaricata, Pertusaria aff. alpinoides, P. commutans, P. ophthalmiza, P. sphaerophora, P. subcomposita, Phlyctis aff. argena, Physconia hokkaidensis, Porina farinosa, Punctelia subrudecta, Pyrenula balia, P. castanea, P. laevigata, P. neojaponica, Rhizocarpon badioatrum, Rinodina fimbriata, R. oleae, R. polyspora, R. pyrina, R. sophodes, R. teichophila, Scoliciosporum chlorococcum, Sphinctrina tubaeformis, Stigmidium fuscatae, Taeniolella phaeophysciae, Thelotrema nipponicum, Toninia aromatica, Topeliopsis aff. azorica, and Trypethelium indutum); and two new for China (i.e. Caloplaca bassiae, Lecania rabenhorstii). Detailed locality data and annotations are given for further 22 noteworthy species, which are rare in South Korea (i.e. Agonimia opuntiella, Agonimiella pacifica, Amandinea punctata, Biatora longispora, Brigantiaea ferruginea, Caloplaca squamosa, Chrysothrix candelaris, Coenogonium luteum, Diploschistes actinostomus, Hyperphyscia crocata, Leucodecton desquamescens, Menegazzia nipponica, Pertusaria commutata, P. multipuncta, P. quartans, P. submultipuncta, P. aff. subobductans, P. velata, Phaeophyscia orbicularis, Porina leptalea, Pyrenula pseudobufonia, and Trapelia coarctata); and for two species rare in China (i.e. Buellia badia, Letrouitia transgressa).

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Authors: S. Y. Kondratyuk, L. Lőkös, E. Farkas, S.-O. Oh and J.-S. Hur

One new genus, i.e. Ivanpisutia S. Y. Kondr., L. Lőkös et J.-S. Hur, similar to the genera Carbonea and Lecidella of the Lecanoraceae, and eleven new species of lichen-forming and lichenicolous fungi, i.e. Agonimia cavernicola S. Y. Kondr., L. Lőkös et J.-S. Hur, Caloplaca chujaensis S. Y. Kondr., L. Lőkös et J.-S. Hur, Lichenochora makareviczae S. Y. Kondr., L. Lőkös et J.-S. Hur, and Rusavskia coreana S. Y. Kondr. et J.-S. Hur from South Korea; Caloplaca neobaltistanica S. Y. Kondr. et J.-S. Hur from China; and Caloplaca mandshuriaensis S. Y. Kondr., L. Lőkös et J.-S. Hur, Ivanpisutia oxneri S. Y. Kondr., L. Lőkös et J.-S. Hur, Lecanora lojkahugoi S. Y. Kondr., L. Lőkös et J.-S. Hur, Lecidella mandshurica S. Y. Kondr., L. Lőkös et J.-S. Hur, Opegrapha verseghyklarae S. Y. Kondr., L. Lőkös et J.-S. Hur and Rusavskia ussurica S. Y. Kondr. et J.-S. Hur from the Russian Far East, are described and illustrated, compared with closely related taxa.

Fourteen species of lichen-forming and lichenicolous fungi are reported as new for South Korea (i.e. Arthonia molendoi, Caloplaca arenaria, C. sideritis, Candelariella coralliza, Lecanactis cf. dilleniana, Micarea misella, Porina aff. ahlesiana, P. distans, Protoparmeliopsis pseudogyrophorica, Pyxine subcinerea, Stigmidium rivulorum, Stigmidium squamariae, Vouauxiomyces ramalinae, Zwackhiomyces lithoideae); 8 for Russia or the Russian Far East (i.e. Absconditella baegasanensis, Bactrospora cf. corticola, Biatoridium aff. monasteriense, Collemopsidium cf. halodytes, Lecanora cf. hafelliana, Opegrapha phaeophysciae, Phacopsis oxyspora, Polycoccum clauzadei, Vouauxiomyces ramalinae; and 2 species new to China (Caloplaca zoroasteriorum, Seirophora blumii).

Detailed locality data and annotations are given for further 27 noteworthy species, which are rare in South Korea (i.e. Arthonia epiphyscia, Buellia griseovirens, Caloplaca austrocoreana, C. chejuensis, C. micromera, C. multicolor, C. subconcilians, C. trassii, Catillaria atomaroides, Enterographa leucolyta, Fellhanera chejuensis, Fellhanera subtilis, Fuscidea austera, Fuscopannaria incisa, Ionaspis lacustris, Lecania rinodinoides, Lobaria japonica, Lobaria spathulata, Micarea coreana, Phaeophyscia endococcinodes, Physcia stellaris, Pyxine limbulata, Scoliciosporum chlorococcum, S. umbrinum, Sculptolumina japonica, Trapelia coarctata, T. placodioides); and for 3 species rare in Russia (i.e. Dactylospora lobariella, Megalospora tuberculosa, Nipponoparmelia perplicata); and Dimelaena aff. oreina in China.

Arthonia epiphyscia is for the first time recorded from Anaptychia isidiata, and Arthonia molendoi is for the first time recorded from Caloplaca subscopularis.

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Authors: S. Y. Kondratyuk, L. Lőkös, E. Farkas, S.-O. Oh and J.-S. Hur

Eleven new for science species of lichen-forming fungi, i.e.: Amandinea pseudomultispora, Buellia chujadoensis, Fuscidea coreana, F. extremorientalis, Hafellia extremorientalis, H. pseudosubnexa, Halecania subalpivaga, Lecanactis subdilleniana, Lecania chirisanensis, Maronella coreana, and Melanophloea coreana are described, illustrated and compared with closely related taxa. Amandinea polyspora, Catillaria nigroclavata, Ivanpisutia oxneri, Lecanora saligna, L. sambuci, and Lecidella mandshurica are proved to be new to Korea.

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