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  • Effect of molybdenum treatment on the element uptake of plants in a long-term experiment
    121-125
    Views:
    102

    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.

  • Overview of test methods used to classify wheat flour and bread samples – REVIEW
    27-34
    Views:
    56

    In Hungary, common wheat (Triticum aestivum ssp. vulgare) is of good quality and world famous. In addition, it plays an important role in the human diet. The classification of flours ground from wheat is quite decisive and there are several methods for its examination. The most important flour testing requirements include moisture content, protein content gluten properties and the most important bakery value number. The measured characteristics give us the opportunity to conclude about the properties of the dough, and then bakery products. Several dynamic and static methods have been developed to study the physical properties of dough. The evaluation of products can be carried out in several respects with the help of a baking test. The multitude of methods currently used to qualify flour, dough and finished products also proves that the overview of the methods is quite topical.

  • Molybdenum - accumulation dynamics of cereals on calcareous chernozem soil
    81-85
    Views:
    97

    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.

  • Change of antioxidant compounds of spices during drying
    77-81
    Views:
    134

    Spices and herbs have been used by humanity for thousands of years, so they are very important plants.

    In this study, the change of dry matter content and antioxidant compounds of eight spices (basil, thyme, rosemary, mint, parsley, lemongrass, chives, coriander) have been examined the raw plants and in plants preserved by three different drying methods (an oven in 50–60°C; drying at room temperature; lyophilisation between -40 and -50°C, under pressure), because we wanted to see the change of the parameters.

    The water content of raw plants was very high, i.e. the dry matter content was very low. By the application of the three drying methods nearly 100% of the water has left the plants, with the exception of the lyophilized basil and rosemary.

    Based on the results related to the original material, lyophilized has proved to be the best treatment for the preservation of antioxidant compounds, however air drying also showed high results for some spices.

     

  • Parameter optimization of an inductively coupled plasma mass spectrometer for measuring arsenic and selenium
    81-85
    Views:
    143

    In the last decades, an increased interest has evolved in arsenic and selenium. The aim is to understand the environmental, agricultural and biological roles of these elements. In the case of arsenic, the major reasons are the relatively high concentration of arsenic in marine biota (mg kg-1) and the arsenic contaminated drinking water bases of some Asian countries, as well as Hungary. The toxicity of higher level selenium content is also known; nevertheless, selenium is essential for several biological functions. Considering its essentialness, in our country, the insufficient selenium intake rate causes a lack of selenium. Measuring the concentrations of these elements provides crucial, but unsatisfactory information, as the speciation, i.e. the form of an element presented in a sample is also required.
    In both cases, the most suitable method to determine concentration is inductively coupled plasma mass spectrometry (ICP-MS). Our objective was to optimize the variable parameters of the ICP-MS to attain the lowest (the best) detection limit. For this purpose, we investigated the effect of parameter change on net signal intensity and relative signal intensity. With the optimized parameter settings, the limits of detection for arsenic and selenium were determined, which are 0,032 ng dm-3 for arsenic, and 0,097 ng dm-3 for selenium. 

  • The importance of selenium in the living world and in the scientific research
    278-286
    Views:
    137

    Presently, selenium (Se) is one of the most investigated microelements. It has an important proven role in many vital processes. Directly or indirectly, selenium deficiency can play a role in the development of many diseases. On the other hand, the concentration range in which selenium is essential is narrow; there is a narrow gap between necessary and toxic content in dietary intake. In this context, selenium contamination poses a further health risk for people if they live near the industrial areas and mining activity.
    In this paper, we comprehensively introduce the very important trace element selenium. We studied the base parameters, deposit, analytic and deficiencies, problem of contamination and also the solution of contamination problems of selenium.

  • Comparison of the sample preparation methods worked out for the examination of the element content of wine
    77-82
    Views:
    113

    The examination of the potentially toxic elements content of the wines is not easy task, because the most elements are in little concentration (mg kg-1 or μg kg-1) in the wine and the wines contain great amount of organic matrix. The efficient sample preparation is essential for the accurate determination of element content. The eim of our research was to determine which sample preparation method will be the most efficient in examination of wines with ICP technology. The examined wine sample was a 2008 Chardonnay from the Eger wine region. We did the sample preparation and analysis examination in University of Debrecen, Centre for Agricultural and Applied Economic Sciences, Institute of Food Science, Quality Assurance and Microbiology.
    We did the analysis examinations with ICP- MS (inductively coupled plasma mass spectroscopy). We always did the sample preparations and the examinations in three times rehearsal. The applied sample preparation methods: dilution with distilled water, open digestion and microwave digestion. 
    We were able to measure B, Al, Mn, Fe and Zn with only dilution and open sample preparation. In the smaller quantity present Sr and Ba were measurable in the wine in the case of all three methods well. We were able to measure the Co with dilution and open digestion method,  while Cr, Ni, and Te with only dilution method. In the case of arsenic we were not able to measure reliable result with dilution and open digestion method because of organic matrix and other components
    (alcohols, monosaccharides, polysaccharides, polyalcohols and inorganic salts). On the whole we are able to say that in the case of certain elements (B, Mn, Fe, Zn, Sr, Ba) the open digestion and dilution sample preparation is applicable well, however, in the case of certain elements (As, Al, V, Cr, Se, Mo, Cd, Hg, Pb) we have to develop the methods. It may be development of one of the way, if we develop sample preparation methods to examined element specifically and not
    to wine generally.

  • Selenium-speciation experiments from soil samples by accept of ionchromatography-inductively coupled plasma mass spectrometry (IC-ICP-MS) method
    106-111
    Views:
    129

    In these days, selenium is one of the most investigated microelements. It has an important proven role in many vital processes. Selenium deficiency can play a role in the contraction of many diseases (e.g. cancer, heart diseases, etc.) and in the aggravation of their clinical aspect directly or indirectly. In this paper, we study the soil samples of an outdoor experiment for the conversion of the inorganic selenium salt that was spread out in different doses. The danger of the wash-out effect was also investigated. Our experiments showed, that most of the inorganic selenite transforms to selenate form during the years, and in this selenate form it moves to the deeper layers of soil.

  • Optimization of inductively coupled plasma mass spectrometer parameter’s to measuring arsenic and selenium
    59-64
    Views:
    160

    In the last decades an increased interest has been evolved about arsenic and selenium. The aim is to understand the environmental, agricultural and biological role of the these elements. In case of arsenic the mayor reasons are the relatively high concentration of arsenic in marine biota (mg kg-1) and the arsenic contaminated drinking waterbases of some Asian countries besides Hungary. The toxicity of higher level selenium content is also known, nevertheless selenium is essential for some biological functions. Considering its esssentiality, in our country the insufficient selenium intake rate couse lack of selenium. Measuring the concentrations of these elements are cruital but not satisfactory information, but the speciation, that is the form of an element presented in a sample is also required. 
    In both cases the most suitable method to determine concentration is the inductively coupled plasma mass spectrimetry. My objective was to optimase the changeable parameters of the ICP-MS for reaching the lowest (the best) detection limit. For this porpuse I have investigated the effect of parameter change on nett signal intensity and relative signal intensity. With the optimased parameter settings the limit of detection for arsenic and selenium were determined, which are 0,032 ng cm-3 for arsenic, and 0,097 ng cm-3 for
    selenium.

  • Effect of molybdenum treatment on the element uptake of food crops in a long-term field experiment
    75-79
    Views:
    123

    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. 

  • Determination of the validation parameters of inductively coupled plasma mass spectrometer (iCP-mS): response curve linearity in the case of arsenic and selenium
    67-71
    Views:
    131

    In the field of elemental analysis inductively coupled plasma mass spectrometers (ICP-MS) have the best sensitivity that means the lowest limit of detection, subsequently their applicability for the detection of essential and toxic elements in foods and foodstuffs is prominent. For the most elements could be measured the detection limit is between μg kg-1 (ppb) and ng kg-1 (ppt) e.g. for arsenic and selenium.

    Considering an analytical task (sample type, analytes and their concentration, pretreatment procedure etc.) the applicability of an analytical method is determined by its performance characteristics. The purpose of validation is to ensure that the method would be used fulfills the requirements of the given task. In this article we describes one of the performance characteristics, the linearity, and the whole validation procedure aims measurement of arsenic and selenium in foodstuffs by inductively coupled plasma mass spectrometer (Thermo XSeries I.); but because of the limited number of pages the results are demonstrated only for arsenic.

    The linearity of calibration was evaluated in three concentration ranges (0.1–1 μg l-1; 1–10 μg l-1; 10–50 μg l-1), with nine line-fit possibilities (without weighting, weighting with absolute or relative deviation; with or without forcing the curve through blank or origin) and different methods (graphical examination, correlation coefficient, analysis of variance).

    The best method to ensure the linearity of correspondence between signal and concentration was the ANOVA test. In view of calibrations it was found that the range of 10–50 μg l-1 could be regarded as linear with four line-fit possibilities, and was non-linear between 0.1–1 μg l-1 and 1–10 μg l-1.

  • SIM Samples Investigation by Statistical Methods
    194-197
    Views:
    60

    The assessment of the present condition of the soil is very important, because the accession of the number of the European Union members is in the near future. This can be the base of the modern agrarian environmental management programme. The assessment must be objective, detailed and analyse the processes in the soil.
    Respecting the above causes was decided to create an Environmental Information Monitoring System. This system consists of more parts. One of them is the Soil Information Monitoring System (SIM). This system started to work in 1992.
    This system has two functions. Creating and actuation is obligatory from the international contracts, on the other hand the public SIM has very important role in the conservation of the soil.
    The SIM territorial measuring grid consists of 1236 measuring points. These points are representatives. The distributions of the points by the types of soil attend the variety of the types of soil of the country.
    The investigated elements in 6 types of soil were in our experiment (the group of scandium and the lanthanide series elements). There are 6 elements above the detection limit (Gadolinium, Neodymium, Praseodymium, Scandium, Samarium, Yttrium).
    The Neodymium concentration is 2 times higher than the content of Gadolinium and Yttrium.
    The Neodymium concentration is 4 times higher than the content of Praseodymium, Scandium and Samarium.
    In the case of Dysprosium, Europium, Lutetium, Terbium, Ytterbium the concentrations were below 1 mg/kg.

  • Effect of molybdenum treatment on uptake of plant and soil molybdenum content in a field experiment
    117-122
    Views:
    113

    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).