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The present research was undertaken to screen for field activity of ethyl-(E,Z)-2,4-decadienoate (pear ester, PE), acetic acid (AA) and the blend of this two components (PEAA) at locations, where high diversity of microlepidopteran species was presumed. By tendency of relative catches, microlepidopterans captured could be divided into two groups: in the first group the PEAA blend resulted in higher catches than single components (Hedya nubiferana, Ypsolopha scabrella and Notocelia trimaculana), while in the second group (Archips rosana, A. xylosteana, Ptycholoma lecheana and Tortrix viridana) only the presence of AA was responsible for attractivity.

In all species, both male and female specimens were caught. This result indicates a potential way to optimise female-targeted lures based on PEAA or AA for all these microlepidopterans that are all recorded as pests. On the other hand, the capture of the above moths in the traps raises the need for some taxonomic knowledge in evaluating captures in PEAA-baited traps currently use in agricultural practice for codling moth monitoring.

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Authors: M. Stéger-Máté, G. Ficzek, E. Kállay, G. Bujdosó, J. Barta and M. Tóth

The variation of some compositional quality parameters in connection with ripening time in the case of four sour cherry varieties ( Prunus cerasus L. Mill.) was studied. Our aim was to optimize the harvest time on the basis of antioxidant capacity. The experiments were carried out in the Érd-Elvira orchards of the Research Institute for Fruitgrowing and Ornamentals (cultivars Érdi bőtermő, Kántorjánosi 3) and in orchards of the Agárd Frucht Ltd. in Agárd (cultivars Érdi jubileum, Maliga emléke). Anthocyanin, polyphenol and vitamin C contents as well as the water-soluble dry matter content of fruits were measured.According to the results of quality parameter measurements it can be stated, that in case of the studied cultivars the optimal picking time for industrial processing is the second picking. At this time the anthocyanin, polyphenol and water-soluble dry matter content of the cultivars are optimal. In general, at the end of the ripening period the fruits shrink, fruit weight and juiciness decreases as a consequence of water loss, therefore determining optimal harvest time for the desired utilization purpose is very important. According to our results, out of the four studied cultivars, Érdi jubileum has the highest values regarding anthocyanin and polyphenol contents.

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Authors: S. Németh, L. Szalay, G. Ficzek, M. Stéger-Máté, G. Sándor, G. Végvári and M. Tóth

A HPLC instrument was used to analyse various acid (citric, malic, succinic acid) and sugar (sucrose, glucose, fructose, sorbitol) components in the fruit of three cultivars grown in Hungary (Gönci magyar kajszi, Mandulakajszi and Harcot), while the β-carotene content was analysed spectrophotometrically. Changes in the chemical content of apricot varieties have not previously been monitored in the course of ripening. The quality of various food products is greatly influenced by the chemical components of the raw materials.The cultivar Gönci magyar kajszi had exceptionally high β-carotene (3.79 mg/100 g in 90% maturity) and sugar content (sucrose: 11253.9 mg/100 g, fructose: 315.2 mg/100 g and glucose: 1434.8 mg/100 g). Mandulakajszi was the most acidic (citric acid: 1597.2 mg/100 g). The malic acid content was similar for all three varieties during ripening. In case of Harcot, the β-carotene content was high in 2008 (3.58 mg/100 g in 90% maturity), however in 2010 it was lower due to environmental influences (2.38 mg/100 g). The pH value was similar for all examined varieties in all ripening stages (3.16–3.50), the TSS/TA value was highest in the 100% mature fruit (18.41) of Gönci magyar kajszi.

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Authors: S. Nagy, E. Kuzmann, T. Weiszburg, M. Gyökeres-Tóth and M. Riedel

Abstract  

Traditional black pottery produced in Nádudvar, E-Hungary, was studied by 57Fe Mössbauer spectroscopy, X-ray diffractometry and microscopy. Quartz, feldspar, clay minerals (kaolinite, smeetite, illite) and calcite were identified in the basic clay material by X-ray diffractometry (XRD). Mössbauer spectroscopy (MS) of the original clay revealed that about 35% of iron compounds were present in goethite while the rest in clay minerals (illite and smectite). After firing the clay in air using an electric furnace (red pottery is prepared in the same way), the Mössbauer spectra showed hematite as the only iron oxide or hydroxide phase, being in good agreement with X-ray diffractometry. In the black product itself, fired in the traditional open-flame furnace, the Mössbauer spectra reflected the presence of iron in magnetite and in sheet silicates with approximately the same relative ratio of oxides and silicates as in the starting material. This can be interpreted as a result of the transformation of goethite to hematite in the first step of firing (in air), and as a reduction of hematite to magnetite in the second step of firing (closed from air). A significant difference was found in the distribution of iron at the Fe2+ and Fe3+ cation sites in the black surface (more Fe2+) and at the dark gray bulk of the fired pottery (less Fe2+), showing that the reduction of Fe3+ occurs in the silicates instead of further reduction of the magnetite (e.g., to wüstite).

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Authors: J. Kristóf, M. Tóth, M. Gábor, P. Szabó and R. L. Frost

Abstract

Intercalation complexes of three different Hungarian kaolinites with hydrazine and potassium acetate were investigated by FT-IR (DRIFT) spectrometry, X-ray diffraction, and thermogravimetry combined with mass spectrometry. Differences were found in the thermal behaviour of the complexes as well as in the rehydration — reexpansion patterns of the heated intercalates. An XRD method is proposed for the distinction of kaolinite and 7.2 Å halloysite present in the same mineral.

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When applied in funnel traps, the known three-component floral lure of Cetonia a. aurata and Potosia cuprea attracts large numbers of beetles. Further increasing the attractive power of these traps offers the opportunity to develop a more potent mass-trapping tool that directly reduces local scarab populations and, hence, fruit damage. The current study was initiated by the observation of adult beetles aggregating and feeding in large numbers on ripening fruit, accompanied by the presence of fermentation volatiles detectable by the human nose. Addition of apple pieces to the ternary C. aurata aurata / P. cuprea lure resulted in increased catches, but only in traps where the apple fermented as a result of beetle feeding. Volatile extracts collected from fermenting apple were subjected to GC-EAG, and bioactive peaks were identified as 1-hexanol, acetic acid, n-butyric acid, isovaleric acid, hexanoic acid and 3-methylphenol by GC-MS and GC peak enhancement. In preliminary field trials, a synthetic mixture of all identified compounds reduced activity of the ternary lure, indicating that some were inhibitory. As certain individual compounds or their particular combinations enhanced activity of the ternary lure only numerically, further experiments are discussed to optimize a synergistic blend of fruit fermentation and/or beetle-derived volatiles.

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Abstract

Molecular epidemiology and genetic features of an extended-spectrum β-lactamase (ESBL) producing Klebsiella pneumoniae epidemic clone (KP-EC) with elevated ciprofloxacin MIC (minimum inhibitory concentration) values from multiple nosocomial outbreaks and sporadic cases between 2006 and 2008 in Hungary were investigated.

As a result of continuous monitoring of ESBL-producing KP-ECs, 27 isolates collected from five healthcare facilities were selected for macrorestriction profile analysis by PFGE (pulsed field gel electrophoresis). Of these, 12 strains were isolated from adult inpatients, while 15 strains were from newborns. The MIC values for several antibiotics were determined by agar dilution technique. Molecular typing was further performed by PCR (polymerase chain reaction) and sequencing of several antibiotic resistance genes, plasmid profile analysis, transfer of resistance determinants and multilocus sequence typing (MLST).

All isolates showed moderate resistance to ciprofloxacin (MICs ranged from 0.5 to 8 mg L−1). PFGE revealed the existence of only one genetic cluster defined as EC IV. PstI digestion of plasmid DNA revealed two highly diverse restriction patterns in “adult” and “newborn” isolates corresponding to plasmids from the Hungarian Epidemic Clone and plasmids isolated from a neonatal nosocomial outbreak in 1998, respectively. Sequence analysis of b-lactamase genes from plasmids of 14 selected isolates detected bla SHV-2a in strains isolated exclusively from newborns and bla CTX-M-15 in strains isolated exclusively from adult inpatients. MLST established that strains of the PFGE cluster belonged to a novel sequence type ST274.

ESBL-producing K. pneumoniae isolates belonging to the novel sequence type ST274 appeared in the newborn and adult hospital settings in Hungary and acquired SHV-2a or CTX-M-15 type enzymes, respectively. Thus, a new antimicrobial resistance strategy for successful conformation to distinct hospital settings was found.

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Authors: J. Tarek-Tilistyák, J. Agócs, M. Lukács, M. Dobró-Tóth, M. Juhász-Román, Z. Dinya, J. Jekő and E. Máthé

The nutritive value, the microbiological safety of oilseed cake (OSC) obtained from naked pumpkin seed (PuC), sunflower seed (SC), yellow linseed (LC), and walnut (WnC), and their impact on wheat flour (WF) dough and bread sensory characteristics at 5% and 10% addition ratio were investigated. The OSCs had high protein (34–50%), fat (8–15%), total dietary fibre (23–36%) content and high energy value (383–444 kcal/100 g)). The OSC samples with a minimal exception fulfilled the requirements of feed legislation in force. An increased water absorption, dough development time, and reduced elasticity were observed probably due to the enhanced fiber and protein content. Dough stability increased with WnC, and decreased with PuC or SC addition. Enrichment provided the appearance of a brown bread for WnC, of a half-brown bread for LC. PuC gave an unusual look. The appearance of OSC fortified bread similar to daily bread, was an advantage resulting the 1st rank for 10% WnC bread and the 2nd one for 10% LC bread (P=0.05). The studied OSCs are suitable for food enrichment, however, in case of PuC and SC fortified flour blends, hydrocolloid application is recommended. Our data suggest that the newly developed fortified breads could be a valuable source for healthy nutrition.

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The blowfly Lucilia sericata (Meigen, 1826) (Diptera: Calliphoridae) is the primary agent of cutaneous myiasis of sheep in northern Europe, southern Africa, Australia and New Zealand. As the application of chemicals has several disadvantages, alternative control measures of traumatic myiasis of livestock must be developed. In this study, the use of entomopathogenic nematodes (EPNs) as potential biocontrol agents against second instar larvae of Lucilia sericata was considered. The following nematode species were tested: Heterorhabditis bacteriophora (IS 5, HHU 1, Hmo1, HNC 1, HAZ 36, Hbrecon, HHU 2, HAZ 29, HHP 88, HHU 3, HHU 4 and HGua), Steinernema intermedia, NC513 strain of S. glaserii, S. anomali, S. riobrave, Steinernema sp. and 5 strains of S. feltiae (22, Vija Norway, HU 1, scp, and IS 6). None of the examined EPN species or strains showed larvicidal efficacy at 37°C (no killing effect was observed in the case of the two heat-tolerant strains - H. bacteriophora and S. feltiae) against L. sericata larvae. At lower temperatures (20°C and 25°C) only strainsof S. feltiae were found to be active. The overall odds ratios calculated for L. sericata maggots to contract S. feltiae nematode infection show significant (p < 0.05) effect only in the case of strains HU 1, 22 and IS 6. In the case of strains HU 1 and 22 parasitic forms of S. feltiae could be detected in the dead larvae of L. sericata. Strain IS 6 (and also Vija Norway at 20°C) penetrated and killed fly larvae, but only adult forms of the nematode occurred in the cadavers.

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Authors: I. Potyó, I. Kása, Cs. Farkas, Gy. Gelybó, Zs. Bakacsi, M. Dencső, E. Tóth and Á. Horel

The present study investigated the quantity of total suspended solids (TSS) in three small catchments and compared the data to turbidity measurements. The TSS data were based on filtration, drying and weight measurements, while the turbidity measurements were retrieved using a handheld device with a turbidity sensor. Water was collected daily at the catchment outlets from November 1, 2016 to May 31, 2017, representing the winter and spring seasons. The lowest quantity of TSS was detected at the catchment outlet of the Esztergályi Stream; however, there were two lakes close to the monitoring point where soil particles may have settled, possibly explaining the low TSS values. The Csorsza and Tetves streams had similar TSS values during winter, but in the spring samples the TSS values were approximately three times higher in the Csorsza Stream than in the Tetves Stream. The relationship between water discharge and TSS values was also investigated for the Tetves Stream, but no significant correlations were observed between them. The results suggested that the labour-intensive TSS measurements (e.g. filtration, soil weight measurements) could be replaced to a good approximation using the handheld device. The spatial heterogeneity within and between the catchments influences the amount of suspended sediment and hence the measurement accuracy. Therefore, the use of the handheld device should also be complemented with other methods, such as the filtration used in the present study, to attain more precise values.

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