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  • Some aspects of food safety from animal origin
    153-155
    Views:
    247

    The relationship between the civilisation illnesses and incorrect nutrition can be considered as demonstrated. The functional foods having one or several nutritional- biological advantage can contribute to the healthy nutrition and to improving the quality of life. Beside the healthy nutrition it is an another important requirement that the food does not contain pathogens or substances of chemical and biological origin namely it has to be safe. 
    In this publication the foods of animal origin were investigated in the point of view of public health hazards arising during their production and processing.
    The contamination and infection of food raw materials, the consequence of chemical substances getting in or developing it the food, the judgement of food deviring from genetically modified or cloned animals are discussed.

  • The examination of presumed Escherichia coli count of raw milk samples on several milk production farms
    31-37
    Views:
    542

    For dairy farms, it is of great importance to insure the appropriate hygienic status of milk and to examine it regularly. Escherichia coli, belonging to the coliform bacteria type of, is a good indicator of contamination, and therefore suitable for characterising the hygienic condition of milk production.
    The aim of our research was to examine the connection between the Escherichi coli count in bulk tank milk and housing and milking technologies of different-sizes farms. We examined the relation using various statistical methods.
    Analysing the connection between the E. coli count and the farm size we found no significant difference between the farms. On the basis of the mean values of the E. coli count, we can say that the hygienic conditions are appropriate for mid-sized farms, and tolerable for large farms. We found differences in the hygienic status among the small farms. Half of the eight small farms, had no adequate hygiene. The results of the analysis of the quality categories show that the probability of inadequate quality milk was the largest on small farms (37.5%).
    Comparing the various housing and milking methods with each other, there were numerical differences in the E. coli count, but these differences were not significant. We got higher E. coli count values on those farms using tied stall barn and bucket milking installation. The reason for this could be that in cases of farms using bucket milking installation, it is harder to meet the requirements.
    After forming groups by farm size, housing and milking methods, we found that the E. coli counts are adequate on mid-size farms using various housing and milking methods; and tolerable on those large farms using loose housing stable and a milking parlour. At the same time, we found inadequate E. coli counts on the smaller farms using tied stall barns and bucket milking installation.
    The results show that if there is suitable attention, independent of farm size, housing and milking procedure, it is possible to produce milk with low E. coli counts, and to insure appropriate hygienic conditions.
    Further detailed examinations are needed to decide which factors of housing and milking technologies influence the E. coli count of bulk tank milk.

  • Applicability of hyperspectral technology for in situ phytoremediation
    71-78
    Views:
    486

    The characterization of heavy metal polluted abandoned mining sites is a complicated assignment due to the variable spatial distribution of the pollutants, therefore complex integrated method is required in order to assess precisely the amount and the distribution of the contaminants. The examined area is flotation sludge reservoir of abandoned Pb-Zn mining site with serious heavy metal contamination. located in Gyöngyösoroszi, Northern Hungary.
    The hyperspectral image of the flotation sludge is obtained by using a Digital Airborne Imaging Spectrometer DAIS 7915, in the frame of DLR HySens first Hungarian hyperspectral flight campaign (21/08/2002). Parallel to the flight campaign heavy metal content of soil samples were examined from the area of the flotation sludge. The analysis of hyperspectral data was verified by the examination of mine tailing samples by FPXRF (Field Portable X-ray Fluorescence spectrometry) (NITON XL-703).
    Determinations of heavy metal containing minerals are based on the spectral profiles of the pixels of the area with using USGIS standard spectral profiles of the examined materials (galena, pyrite, sphalerite, goethite and jarosit).

    Applying the Spectral Angle Mapper with BandMax classification the distribution of minerals (galena, pyrite, sphalerite, goethite, jarosit) in the area was defined. The mineral formation occurs especially at the levees and the barren places of the Szárazvölgyi flotation sludge reservoir. Based on the statistic results of the samples, principal component analysis and correlation coefficient between the different metal content of the samples were calculated. The highest correlations were found between Pb-Zn, Fe-Zn and between Fe-Pb. This prove the results of the principal component analysis, where usually Pb, Zn, Fe introduce the main component.

    Canopy analysis was also carried out with the hyperspectal image in order to classify the differences between vegetation types at the Szárazvölgy flotation sludge reservoir and analyse the applicability of it. Supervised classification methods were used to distinguish 8 vegetation types based on the spectral properties of the area. The results of the classifications were compared to a ground truth image, based on ortophoto, topographic map, and GPS based field data collection. According to results of the comparison, the paralellpiped classification method is proved to be appropriate method based on the overall accuracy of canopy classification, which was 54% due to heterogeneity of the vegetation. 

    The results of hyperspectral data and FPXRF analysis suggest that Pb, Zn and Fe containing minerals have similar spatial distribution in the examined and barren area.

    Based on this study hyperspectral remote sensing is likely to be an effective tool for the characterization and modeling the distribution of Pb, Zn and Fe containing minerals at the examined heavy metal polluted sites. Further more, based on the vegetation analysis plant species for phytoremediation can be defined.

  • Potential use of bamboo in the phytoremediation in of heavy metals: A review
    91-97
    Views:
    913

    There are many literature sources focusing on the phytoremediation of woody plants, but there are only few dealing with the phytoremediation of bamboo plants. Phytoremediation technology has the advantages of little disturbance to the environment and low remediation cost. Bamboo mainly exists in tropical and subtropical regions. As an energy plant, bamboo has a fast growth cycle, large biomass, simple cultivation, high economic efficiency, and convenient harvesting, which highlights the advantages of bamboo in phytoremediation. In addition, bamboo plants have good tolerance and uptake ability to heavy metals and have high application potential and development value in uptaking heavy metal contaminated soil. However, due to climate, temperature and other reasons, bamboo cannot be widely planted in most countries. Research status of remediation of heavy metal contaminated soil by bamboo plants is summarized. The feasibility of its application in heavy metal contaminated soil is discussed in this paper. Aiming at the shortcomings of existing research, bamboo plants have a prospect in the field of plant phytoremediation for the future.

  • Correlations of the global, regional and local factors of the anthropogenic effects on the water reserves of the Earth’s crust
    85-92
    Views:
    223

    The decrease in Earth's drinking water resources and the degradation of its quality has become a critical problem. Our planet's total water supply is estimated to be around 2 billion km3s. This is only 1% of Earth's own weight. Of this small amount only a tiny 3% is fresh water, of which 79% is forzen in glaciers and 1% is present as surface waters.The ratio of water stored in soil is around 20%. This is 0.2% of the total water supply. Our study aims to summarize the layered groundwater aquifer systems and its changes which are the results of anthropogenic effects in both global and hungarian respects and also for the region of Debrecen.In particular with regard to the geological and ecological level where irreversible
    processes take place. All this is discussed in the context of cause and effect. Pointing out the dangers of excessive deep groundwater extraction and the contamination caused by toxic substances that are the byproducts of modern life. In addition we discuss the Water Directive of the European Union which gives a policy for community action concerning the goal to achive the status of „in good condition” for our waters till 2015.

  • The Importance of Environmental Research of the Great Hungarian Plain
    9-16
    Views:
    162

    The research of the Great Hungarian Plain has been going on for a long time and there are a lot of information could be used by environmental protection too. The connection between the two topics are diversified, that is why it is necessary to choose a few subject to explain. The chosen subjects are:
    The protection of the geological media cannot be solved, either practically and legally, with the protection of the separated elements of that, just if we see it as a system.
    The prevention, which is the most effective (and also the most inexpensive) way of environmental protection, can be supported by the compilation of vulnerability- and risk maps (i.e. risk of inland water, erosion vulnerability, deflation vulnerability, contamination sensibility).
    Survey on the environmental state containing indispensable geological information for the optimal land use and country planning of a region, county or settlement.
    Marking out of the possible areas for waste depositing.

  • Effect of molybdenum treatment on the element uptake of food crops in a long-term field experiment
    75-79
    Views:
    480

    Molybdenum, as a constituent of several important enzymes, is an essential microelement. It can be found in all kind of food naturally at low
    levels. However, environmental pollution, from natural or anthropogenic sources, can lead to high levels of the metal in plants. Our study is based on long-term field experiments at Nagyhörcsök, where different levels of soil contamination conditions are simulated. Plant samples were collected from the experiment station to study the behavior of elements: uptake by and transport within the plants, accumulation in different organs, phytotoxicity and effects on the quantity and quality of the crop. In this study, we present the effect of molybdenum treatment on the uptake of other elements. Molybdenum is proved to be in an antagonist relationship with copper and sulphur, while molybdenum-phosphorus is a synergist interaction. However, in most of the plants we studied, increasing molybdenum-treatment enhanced cadmium uptake. We found the most significant cadmium accumulation in the case of pea, spinach and red beet. 

  • Effect of molybdenum treatment on uptake of plant and soil molybdenum content in a field experiment
    117-122
    Views:
    583

    Molybdenum is not a well-known microelement, but being a constituent of several important cellular enzymes it is an essential microelement. Molybdenum occurs in all foods, but at very low levels. There does not appear to be any particular foods or types of foods, which in the absence of extrinsic factors, naturally have high levels of molybdenum. However, environmental pollution, from natural or anthropogenic sources, can lead to high level of the metal in plants.
    Our study is based on the long-term field experiments of Nagyhörcsök, where different levels of soil contamination conditions are simulated. Soil and plant samples were collected from the experiment station to study the behaviour of molybdenum: total concentration, available  concentration, leaching, transformation, uptake by and transport within the plants, accumulation in different organs, phytotoxicity and effects on the quantity and quality of the crop. In this work we present the results of maize and peas and the soil samples related to them.
    According to our data molybdenum is leaching from the topsoil at a medium rate and it appears in the deeper layers. In the case of plant samples we found that molybdenum level in the straw is many times higher than that is in the grain, so molybdenum accumulates in the vegetative organs of the plant. The data also show differences in the molybdenum-uptake of cereals and Fabaceae (or Leguminosae).

  • Effect of molybdenum treatment on the element uptake of plants in a long-term experiment
    121-125
    Views:
    409

    Molybdenum as a constituent of several inmportant enzymes is an essential micorelement. It can be found in all kind of food naturally at low level, however, environmental pollution, from natural or anthropogenic sources, can lead to high level of the metal in plants. Our study is based on the long-term field experiments of Nagyhörcsök, where different levels of soil contamination conditions are simulated. Plant samples were collected from the experiment station to study the behaviour of elements: uptake by and transport within the plants, accumulation in different organs, phytotoxicity and effects on the quantity and quality of the crop.
    In this work we present the effect of molybdenum treatment on the uptake of other elements. Molybdenum is proved to be in an antagonist relationship with copper and sulphur, while molybdenum-phosphorus is a synergist interaction.
    However, in most of the plants we studied increasing molybdenum-treatment enhanced cadmium-uptake. We have found the most significant cadmium-accumulation in the case of pea, spinach and red beet.

  • The Role of Trichoderma in the Rhizosphere of Tomato Plants
    67-69
    Views:
    159

    It is well established that microorganisms are closely associated with the roots of plants can directly influence plant growth and development. Species of Trichoderma, on the other hand are primarily studied for their ability to control plant disease. The ability of species of Trichoderma to directly promote or inhibit plant growth has been noted for many years.
    Tomatoes were treated with different Trichoderma strains by seed treatment and soil inoculation. The Trichoderma were grown on malt-agar medium and conidia were washed off by sterile water for making suspension which contained 107 CFU/ml (colony forming unit/ml). The suspension was used for seed treatment and for the soil inoculation by watering as well. The artificial soil inoculation was made by Trichodermas growing on grounded maize were mixed in mould and tomato seed were sown in it. Tomato seeds were also sown in bags made of close-meshed material which allowed the soil microorganisms to colonize the roots but it simultaneously protected the roots from soil contamination. Roots were put on Trichoderma selective medium to check the root colonization of the Trichoderma.
    The tomato plants were bedded out in a field in four repetition. After harvesting by hand the results supported by statistics shown that there was significant differences between the yield of the untreated and treated tomato plants by Trichoderma strains.

  • Plant production possibilities on a heavy metal contaminated soil with the purpose of biorefinery
    215-222
    Views:
    257

    Significant part of not cultivated area of Hungary is not suitable for agricultural utilization because of industrial
    pollution. Technologies of biorefinery make reutilization of contaminated areas possible. Biomass of plants
    produced on polluted soils can be raw material of valuable products. Applicability of biorefinery was tested on a
    heavy metal polluted soil, where the contamination originated from previous mining activity. Complete biomass
    utilization was aimed to obtain cosmetic ingredients, pharmaceutical agents, and precursors. During our research
    work 88 plant species and varieties were produced and tested for potential utilizable components. Levels of
    possible contaminants in these plants were monitored, and amounts of carbohydrates, protein, organic acid and
    cellulose were determined as well. Different plant extracts were tested as potential sources of biologically effective
    components or as raw materials for lactic acid fermentation. Our results show that biorefinery is a real possibility
    for utilization of polluted areas. Numerous plants could be cultivated on contaminated areas without increased
    levels of contaminants in their tissues, thus they can be sources of valuable compounds.

  • Classification of a diffuse heavy metal polluted mining site using a spectral angle mapper
    119-123
    Views:
    868

    Characterization of heavy metal polluted abandoned mining sites is complicated, as the spatial distribution of pollutants often changes dramatically.
    In our study, a hyperspectral data analysis of the Gyöngyösoroszi abandoned Pb-Zn mine, located in northern Hungary, where Záray (1991) reported serious heavy metal contamination, was carried out using ENVI 4.3. In this area, galena (PbS), goethite (FeO(OH)), jarosite (KFe3(SO4)2(OH)6), sphalerite ((Zn, Fe)S) and pyrite (FeS2) were the predominant minerals in the alteration zones was chosen as the target mineral.
    Spectral angle mapper (SAM) and BandMax classification techniques were applied to obtain rule mineral images. Each pixel in these rule images represents the similarity between the corresponding pixels in the hyperspectral image to a reference spectrum.
    As a result of hyperspectral imagery the distribution of pyritic minerals (sphalerite, galena) in the area was defined. Both of the mineral formations occur, especially in mine tailings, the area of the ore preparatory, and the Szárazvölgyi flotation sludge reservoir. According to the results, jarosite and goethite have similar distributions to sphalerite and galena. The results showed that hyperspectral remote sensing is an effective tool for the
    characterization of Pb, Zn and Fe containing minerals at the examined polluted sites and for modelling the distribution of heavy metals and minerals in extensive areas.
    This classification method is a basis of further detailed investigations, based on field measurements, to map the heavy metal distribution of the studied area and to quantify the environmental risks caused by erosion, which include DEM (digital elevation model) and climatic and hydrological data sources. Furthermore, it can be used primarily to support the potentially applicable phytostabilization technique and to isolate hot spots where only ex-situ remediation techniques can be applied.

  • Molybdenum - accumulation dynamics of cereals on calcareous chernozem soil
    81-85
    Views:
    611

    This work is about the molybdenum-accumulation of cereals analyzing soil and plant samples from a field experiment set in
    Nagyhörcsök by Kádár et al. in 1991.
    In this long-term field experiment different levels of soil contamination conditions are simulated. Soil and plant samples were collected
    from the experiment station to study the behaviour of molybdenum.
    In this report results of maize, winter wheat, winter barley and soil analysis are presented. The conclusions are as follows:
    – Analysing soil samples from 1991 we have found that roughly half of the molybdenum dose applied is in the form of NH4-acetate+EDTA soluble
    – Comparing element content of grain and leaf samples we have experienced that molybdenum accumulation is more considerable in the  vegetative plant parts
    – Winter wheat accumulated less molybdenum then maize in its vegetative parts. Comparing molybdenum content of winter wheat to winter barley we found that the concentration of the element in wheat was lower by half than in the winter barley. It seemed that molybdenum accumulated to the least degree in winter wheat.

  • Studies on the Suitability of Different Mould Media Compositions for the Mycological Evaluation of Hay Samples
    34-38
    Views:
    164

    t evaluating mould contamination of hay samples in more than the half of the cases Mucor spp. (and Trichoderma spp. in a smaller extent) overgrew slower developing moulds, spoiling the assessment of total mould CFU and the detection of fastidious organisms, among others the toxinogenic Fusaria. In parallel microbiological evaluation of hay samples comparing to the ISO 7954 medium as reference a) the overgrowth inhibiting effect of Rose Bengal (ISO 7954-RB); b) the combined inhibiting effect of Rose Bengal and Dichloran (dichloro-mononitroaniline) in DRBC; c) the inhibition of Dichlorane in ISO 7954 (ISO 7954-DC); d) the lowering of nutrient levels to 1/4 (1/4 N ISO 7954, 1/4 N-DRBC and 1/4 N-DC); e) the inhibiting effect of dinitro – salicylic – acid (DSA), a reducing sugar binding compound, as a potential growth inhibitor (RBC-DSA) were studied. The results showed, that 1) MSZ-ISO 7954 medium codified by the official method was unsuitable for the detemination of mould count and for the detection of toxinogic spp. in hay samples. In half of the cases the overgrowth of Mucor has spoiled CFU enumeration and recognition of toxinogenic moulds; 2) Inhibitor supplemented DRBC medium (King et al., 1979) enabled early CFU enumeration by uniforming colony sizes and by efficient suppression of Mucor, but the pink background colour of the medium was disturbing the observation of tints of conidia, which were characteristical to toxinogenic moulds like Fusaria. The hypha-staining property of Rose Bengal did not prove very important; 3) According to the recent stage of our studies, the ISO 7954-Dichloran combination can be recommended for the mycological evaluation of hays and dried roughages. CFU can be enumerated early, Mucor suppressed in the same extent as with DRBC and colours are easily observable; 4) 2-4-Dinitrosalicylic-acid (DSA) proved unsuitable as inhibitor, for its poor efficiency and for its intense yellow background coulour.

  • Risk effects of the spread route of mycotoxins
    90-95
    Views:
    506

    In Hungary the mycotoxin is a great problem, because there are many natural toxins in wheat and maize. These cereals can be found on
    considerable proportion of the country’s sowing area, and they are deterministic food for the population. The direct human and animal
    utilization of the contaminated cereals mean a serious risk in the food chain. In Hungary’s climate the soil is contaminated with pathogen
    moulds, particularly Fusarium species, which increase by respective temperature and moisture content in cereals. The Fusarium can
    decrease the quality of the wheat in different ways: decrease the germination capability and cause visible discoloration and appearance of
    mould, reduces the dry material and nutrient content of the grain. From the toxins produced by the Fusarium genus, the trichotecene (T-2,
    HT-2, deoxinivalenol, nivalenol, diacetoxyscxirpenol, Fusarenon-X) and the estrogenic zearalenon (F-2) are the most common in Hungary.
    The fumonisins (FB1, FB2, FB3) first identified in 1988, relatively newly discovered, are also important. Major proportion of mycotoxins in a
    healthy organization is metabolized by the enzyme system of liver and intestinal bacteria. The toxicity is reduced or even leaves off.
    However, more toxic and biologically active compounds can be formed. For the reduction of mycotoxin-contamination several possibilities
    are available in the case of storage, processing and feeding.

  • Comparative analysis of sample preparation methods to determine the concentration of arsenic in soil- and plant-samples
    167-170
    Views:
    478

    Arsenic contamination of the fields and groundwater is a global problem. Alföld is the most affected area in Hungary. Irrigation witharsenic contaminated water, and crop production on the contaminated soil can cause a food safety problem, because arsenic is easy taken up by the cell of the plant roots. To prevent this, very important to monitoring the arsenic content of soils and plants. Inductively coupled plasma mass spectrometry (ICP-MS) is a fast, easy method to determined the concentration of minerals in the case of plant and soil samples The analytical methods can give reliable, results if the analytical process, including the sample preparation method, is the best. The objective of this study was to compare 3 type of sample preparation method which was dry ashing, wet digestion in open system, and microwave digestion. As a result of our experiement shows the microwave digestion is the appropriate method to determined the arsenic content of soil samples. In the case of plant samples we can use wet digestion in open system or microwave digestion as a samle preparation method.

  • Comparative analysis of Staphylococcus aureus strains by molecular microbiology methods
    34-39
    Views:
    560

    Staphylococcus aureus is a very important pathogen for dairy farms and milk processing plants. Subclinical mastitis is often caused by this species, and it can contaminate bulk tank milk when milking cows are suffering from mastitis. Additionally, thermostable enterotoxins (SE) produced by some types of this bacterium can cause food poisoning.
    The aim of our research was to examine the number of S. aureus in bulk tank milk in two dairy farms and the enterotoxin-producing ability, genetic relation (pulsotype) and antibiotic resistance of S. aureus strains from different sources (bulk tank milk, udder quarter milk and environment).
    The results show that the mean number of S. aureus of bulk tank milk of two farms significantly differed (P<0.05). Fourteen isolates were selected for further molecular genetic studies (five isolates were from bulk tank milk and nine isolates were from udder quarter milk). S. aureus was not recovered from the environmental samples. Three of the fourteen isolates (21.4%) tested by multiplex PCR were positive for SE genes. Two isolates carried one gene (seb) and one isolate carried two genes (seg and sei). The fourteen strains were classified into three pulsotypes and two subtypes at 86% similarity level. Isolates from bulk tank milk (n=5), were divided into 2 pulsotypes (A, C) and one subtype (C1). The isolates from udder quarter milk (n=9) belonged to three different pulsotypes (A, B, C) and two subtypes (A1, C1). The distribution of pulsotypes in the present study revealed genetic relationship between S. aureus isolated from udder quarter milk and bulk tank milk. This could be explained by the fact that in farms with a high number of infected cows, these cows could represent the main source of contamination. The results of the antibiotic resistance investigations show, that all strains were susceptible to methicillin, cefoxitin, lincomycin, tetracycline, erythromycin and sulfamethoxazole/trimethoprim. Thirteen out of fourteen strains were resistant to penicillin (A and C pulsotypes, A1 and C1 subtypes) and just one isolate was susceptible (B pulsotype) to all antibiotics tested.