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  • Aflatoxin production on agricultural products
    67-71
    Views:
    160

    Aflatoxins due to their toxicity pose significant economic and human health threat; therefore, it is important to avoid this type of contamination in agricultural products. Until now significant aflatoxin contamination occurred mainly in foods of tropical and subtropical origin because the optimal growth of the producer Aspergillus species is between 32–38 ºC. Nowadays the aflatoxin contamination is becoming higher threat in Hungary, due to the imported products, the rising average temperature and the climatic changes. There is a significant knowledge on the genetic and environmental effectors of the aflatoxin production; however, it is remained a great problem to control mold contamination and toxin production in farming and stock-raising. Here we attempted to summarize the knowledge on aflatoxin production and attempts of the elimination.

  • The importance of selenium in the living world and in the scientific research
    278-286
    Views:
    233

    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.

  • Surface polishing method application to reduce micotoxin content of mill wheat
    339-342
    Views:
    151

    The fungi causing the infection and most of the harmful toxins they produce are concentrated in the bran of the grain, thus the intensive surface cleaning, the so-called debranning operation could allow the reduction of contamination in the milling technology. The essence of the PeriTec technology – originally developed by SATAKE, a Japanese company, to clean rice – is that it gradually removes the bran layers of the grain by mechanical means before further processing. We modeled the PeriTec technology with a laboratory size, batch-operating, horizontal debranning machine by SATAKE. The flour, milled grain after grinding 40 sec, the initial toxin content was only a small proportion (~15–20%) measured. The results showed that below the limit of DON toxin contaminated wheat (DON: 1.15 mg kg-1) during the grinding surface of the detached bran toxin contamination shows a very high (6.16 mg kg-1). The 40 seconds debranning before grinding shows lower DON toxin content than without debranning. So it is importance before the grinding. The toxin contamination of the bran fractions is significantly reduced, which is importance to the feeding point.  As a result of debranning, the toxin content of the grinding fractions decreased, which justifies that that PeriTec method is suitable for the reduction of toxin contamination. 

  • Utility of Winter Wheat According to Visual and Microbiological Fusarium Infection, as Well as Toxin Examination
    26-34
    Views:
    105

    In 1998 the Fusarium infection was studied visually and microbiologically and also F-2, T-2, HT-2, DAS and DON contamination were measured using 22 winter wheat samples. The correlation between the different parameters of 22 wheat samples were determined by regression analysis. According to our results we can state the following.
    There is no significant connection between the results of visual, microbiological and toxicological examinations. This means that no certain conclusion can be drawn about the toxin contamination of samples – which is a determining factor of its utility – based on the visual symptoms and the plate dilution method.
    Our results indicate however – though it is not proven statistically – that those samples in which the Fusarium infection did not exceed the limit of the standard, also had low toxin contamination, therefore they can be used as components of forage.
    It is a considerable problem, however, that according to the visual qualification, such samples are excluded from the later utilisation, wherein the toxin contamination does not justify such action. Therefore, it is necessary to examine the toxin content of those samples which show high infection by visual symptoms. To reducing the number of expensive toxin examinations it would be advisable to change the currently used 0,5% limit which is indicated in the standard for a higher value of infection, for example to 2%, as recommended by Mesterházy (1998).

  • Effect of cadmium and zinc contamination on the population dynamics of soil microorgani
    73-77
    Views:
    124

    Changes in the population dynamics of microorganisms in a soil artificially contaminated with various doses of cadmium and zinc was examined from a quantitative point of view, under laboratory circumstances. The research was based on a chernozem soil originating from the area of a long-term microelement contamination model experiment (Nagyhörcsökpuszta, Hungary), which was carried out during 1991 in the Experimental Site of the Institute of Soil Science and Agricultural Chemistry, Centre for Agricultural Researche Hungarian Academy of Sciences, Budapest, Hungary. According to the amount of bacteria, microscopic fungi and nitrifying bacteria, it can be stated that the effect of contamination can be observed even in the perspective of nearly two decades. In more cases significant changes in the number of soil bacteria and microscopic fungi could be observed, and the nitrification activity increased in case of both microelements. Therefore the further research of changes in microbial activity of these soils can provide novel scientific results.

  • Microbiological quality of bulk tank raw milk from two dairy farms in Hajdú-Bihar County, Hungary
    105-112
    Views:
    327

    Two main channels have been identified to be responsible for microbiological contamination of raw milk and milk products. Firstly, contamination has occurred due to udder infection from the cow or the blood which harbours most bacteria that come in contact with the raw milk. Secondly, via external factors (may include faeces, skin, contaminated water, environment etc.) which are associated with the operation of milking. There is direct contact with the milk and/or surfaces before, during or after the milking, posing public health risk and economic decline. The aim of this study was to examine the bacteriological quality of bulk tank raw milk samples collected from two different size dairy farms (Farm 1 and Farm 2) of different housing forms (cubicle loose and deep litter) in Hajdú-Bihar County, Hungary in July, 2017. Three samples were taken from each farm, and the total plate count, coliform count, Escherichia coli count, Staphylococcus aureus count, and yeast and mould count were determined in them.

    The results clearly showed low level of all measured bacteria group load in Farm 1 samples in comparison to Farm 2 with the exception of coagulase-negative Staphylococcus (CNS) which represented high level in general, indicating significant difference (P<0.05). The mean value of total plate count in Farm 2 samples was higher (1.0 × 105 CFU/mL) than Farm 1 samples (2.8 × 104 CFU/mL). There was a significant difference (P<0.05) in mean count of coliforms in raw milk samples between Farm 1 and Farm 2. Similarly, results of E. coli were significantly different (P<0.05) with mean count of 1.44 × 102 CFU/mL and 2.02 × 103 CFU/mL for Farm 1 and Farm 2 respectively.

    Results of Staphylococcus aureus also showed significant difference (P<0.05) with mean count of 9.7 × 101 CFU/mL for Farm 1 and 6.28 × 102 CFU/mL for Farm 2. The mean of mould count recorded was 1.07 × 102 CFU/mL and 4.93 × 102 CFU/mL for Farm 1 and Farm 2 respectively. The recorded mean of yeast count was 1.68 × 103 CFU/mL and 3.41 × 103 CFU/mL for Farm 1 and Farm 2 respectively; however, both farms showed no significant difference (P>0.05) in terms of mean of mould and yeast count. Although Farm 2 produced six times lower milk quantity than Farm 1, the measured microbial parameters were high. Both farms’ microbiological numbers were higher above the permitted limit values as stated by Regulation (EC) No 853/2004, Hungarian Ministry of Health (MoH) 4/1998 (XI. 11.).

    This could be an indication of non-conformance to effective GMP, ineffective pre–milking disinfection or udder preparation, poor handling and storage practice, time and temperature abuse and inadequate Food Safety Management System Implementation. Therefore, our recommendation is as follows; establish control measures for pre- and postharvest activities involved in the milking process which would be an effective approach to reduce contamination of the raw milk by pathogenic microorganisms from these farms, strict sanitation regime and hygiene protocol be employed and applied to cows, all equipment, contact surfaces and minimize handling of the milk prior, during and after milking. This will also serve as scientific information to the producers for continual improvement in their operations.

  • Heavy Metals in Agricultural Soils
    85-89
    Views:
    82

    The soil constitutes the basis of the food chain. To keep soil conditions in a good trim is very important, it’s part of the sustainable development and of producing food supply harmless to health.
    In some cases, soil productivity is the only important part, qualitative requirements or economical characteristics can improve it. The soil is threatened by two danger factors: the soil degradation and the soil pollution. The accumulation of different harmful and/or toxic substances in the soil is well known. Heavy metals constitute a part of it. Metals in the soil and in the soil-solution are balanced. This balance depends on the type of the metal, on the pH, on the cation-band capacity of the soil, on the redox relations and the concentration of cations in the soil.
    To be able to handle the metal contamination of the soil, it is important to estimate the form, the possible extension and the concentration of metals.
    Of course, the different types of soils have different physical-chemical, biological and buffer capacity, they can moderate or reinforce the harmful effects of heavy metals. To draw general conclusion of the dispersion and quantitative relations on the metals originated from different contamination sources is hard, because in some emissive sources contamination is limited in small areas but on a high level, some others usually expand on larger areas, and as a result of equal dispersion, the contamination’s level is lower.
    Heavy metals – unlike alkali ions – strongly bond to organic materials, or infiltrate in a kelát form. Their outstanding characteristic is the tendency to create metal-complex forms. Kelats take part in the uptaking and transportation of heavy metals. Heavy metals exert their effects mostly as enzyme-activators.
    The metals cannot degrade in an organic way, they accumulate in living organisms, and they can form toxic compounds through biochemical reactions.
    Lot of the heavy metals accumulate on the boundaries of the abiotic systems (air/soil, water/sediment), when physical or chemical parameters change, and this influences their remobilization.
    Human activity plays a great part in heavy metal mobilization, results in the human origin of most biochemical process of metals.
    To understand the toxic influence of accumulated metals of high concentration, their transportation from soils to plants or their damage in human health, must clearly defined and investigated.
    For effective protection against soil pollution, the types and levels of harmful pollution to soil must identified, regarding legal, technical and soil-science aspects, preferable in a single way. Difficulties in this area mean that toxicity depends on loading, uptake, soil characteristics and living organisms (species, age, condition etc.), furthermore, local and economic conditions considerably differ.

  • Species-specificity of the glutathione reduced form accumulation in the arboreal plants, testing influence of industrial emissions
    105-110
    Views:
    86

    Conducted are researches of dynamics of glutathione reduced form maintenance in the leaves of arboreal plants which grow in the zones of different level of contamination by industrial emissions of“Red Lead Factory” LTD and ArselorMittal Kryvyi Rig. For comparison, similar  investigations were conducted in the intact Botanic Garden in s.c.t. Sofievka. Findings testify to absence of negative influence of industrial emissions and, thus, the arboretum of botanical garden also can be examined as conditional control. It was stated that it is set a few strategies of active oxygen forms and their metabolites deactivation, appearing in cells under action of environment negative factors. To our opinion, fluctuation of glutathione reduced form maintenance can examine as an index of plants stability, on which investigational species can be distributed on steady and moderato steady.

  • Activity of some enzymes, participating in nitrogen compounds transformation in chernozem, polluted by fluorine compounds
    99-104
    Views:
    117

    Contamination of chernozem by fluorine compounds variously affects those enzymes (urease, asparaginase, glutaminase, arginase, amidase), which takes part in the metabolism of nitrogen-bearing organic compounds. In broken soils the inhibited desaminisations is stronger, than enzymatic hydrolysis of asparagine and arginine. The features of seasonal dynamics of change activity of urease and correlation dependence of its activity from some physical and chemical soils properties are described. These tendencies well comport with the results of model experiments. At minimum HF influence there is inhibition of processes of monohydrocarboxylic acids desaminisation, hydrolytic breaking up of arginine and glutamine. By a side with this there is activating of urea and asparagine breaking up processes on the initial stages of toxicant influence. The study of kinetics of process of urea enzymatic hydrolysis in chernozem at the different level of HF influence showed changes of initial and maximal velocity of enzymatic reaction, and also Michaelis-Menten constant. 

  • Coagulase-negative staphylococci in ewe udder surface and raw milk samples
    221-225
    Views:
    181

    Coagulase-negative staphylococci (CNS) are among the major causes of subclinical mastitis in dairy ewe flocks. This has a financially significant impact on the ewe dairy sector and consumer health. The determination of the bacterial count, particularly CNS, is critical in terms of the quantity and quality of ovine milk. Thus, the purpose of this study was to quantify the CNS count in the udder surface and raw milk samples of the ewe, in addition to identifying CNS strains (n=8) collected from udder surface and individual raw milk samples by 16S rRNA gene sequencing. A total of 164 samples of udder surface and raw milk originated from four sheep farms were tested. The obtained values were compared between the different farms. Furthermore, values during 2018 and 2019 in the case of Farm I were compared. Significantly higher (p<0.05) average count was observed in udder surface samples taken from Farm I (2.8±1.0 lg CFU/cm2) than that of Farm III samples (2.3±0.6 lg CFU/cm2). In the case of individual raw milk, the higher value was observed in samples derived from Farm III (3.5±0.9 lg CFU/mL), while the obtained value was significantly lower (p<0.05) in samples originated from Farm IV (1.8±0.4 lg CFU/mL). In the bulk tank milk samples, the highest mean value was 5.3±0.4 CFU/mL, and there was no significant (p>0.05) variation between farms. Coagulase-negative staphylococci counts were decreased to a certain extent in both sample types tested during 2019 except for individual raw milk derived from the Tsigai breed. The correlation between the mean CNS counts of udder surface and individual raw milk was very weak (r=0.048). Staphylococcus simulans, Staphylococcus auricularis, and Staphylococcus equorum were identified by molecular sequencing and Staphylococcus simulans were the most frequently identified CNS species. A higher CNS count of bulk tank milk than individual raw milk indicates possible contamination during milking and storage. Therefore, further studies are required to investigate the other sources of bulk tank milk contamination to improve the hygienic quality of milk.

  • Wheat cleaning and milling technologies to reduce DON toxin contamination
    89-95
    Views:
    266

    Mycotoxicosis caused by Fusarium fungi holds a huge risk considering economic and food safety issues worldwide. By applying milling technologies, we attempted to reduce the concentrates of DON toxin, as it is the most often found toxin in wheat.

    The processes of sieving, aspiration and combination had been used on wheat with high DON toxin concentration. As a next step, grains were sorted using a horizontal cylinder separator, assorted by an optical and a gravity separator, and finally, the products were scoured and ground. The contamination level of the wheat and flour samples were defined by the HPLC-MS method.

    Regarding the results, it can be stated that toxin concentration was most effectively reduced by optical separation and scouring, and by applying these milling techniques, food safety can be increased significantly.

  • The effect of keeping technology on the microbiological status of raw milk
    67-75
    Views:
    135

    The importance of the quality of raw milk increased after Hungary had joined to the EU. On delivery of raw milk, the microbiological quality, especially total plate count of the milk is very important. Twenty-two farms (7 large, 4 medium-sized, and 11 small farms) were included in the study. We considered the different farm size, keeping- and milking circumstances during the selection of farms. The examined large farms use loose housing system (cubicle, deep litter) and milking parlour. Most of them use preand post-milking disinfection. In the medium-sized farms, loose,
    deep litter and tie-stall housing system, as well as milking parlour, pipeline milking and bucket milking occurred. All of them use preand post-milking disinfection. Small farms use tie-stall housing system, bucket milking and udder preparation by water. Unfortunately, they do not use pre- or post-milking disinfection. In the large and medium-sized farms mainly Holstein Friesian, in the small farms Hungarian Simmental breeds can be found.
    The aim of our research was to examine the microbiological status of the raw milk produced in dairy farms (total plate count, coliform count, Escherichia coli count, Staphylococcus aureus count, psychrotroph bacteria count, furthermore yeast and mold count); sources of the contamination; connection between the microbiological quality of produced milk and housing-, milking technologies of farms; furthermore the hygienic circumstances of milking and milk handling of the farms, by the examination of coliform bacteria and Escherichia coli contamination.
    During the examination of the connection between the different farm sizes, various housing- and milking forms and the microbiological characteristics we observed similar tendencies in the case of total plate count, coliform count, yeast and molds count, furthermore psychrotroph bacteria count. The value of  these parameters was significantly higher in small farms, and infarms which use tie-stall housing forms, bucket milking, udder preparation with water, and which do not use pre- and post-milking disinfection.
    The results showed that besides cooling, the milking procedure and the type of udder preparation had the largest effect on the total plate count. Statistical analysis shows that in medium and small farms the combination of pipeline milking – tie stall housing system – disinfectant preparation of the udder; in large farms the combination of milking parlour – loose cubicle housing system – dry preparation of the udder are the most appropriate in the aspect of the total plate count. We experienced that in farms where the hygienic instructions are not followed – and therefore
    equipment used during the milking and handling of milk is very contaminated – or rather the separation of mastitic cows’ milk is not appropriate, different microorganisms may contaminate the produced milk. 

  • The study of headspace sampling for the measurement of Volatile Organic Compounds byGC-MS
    35-38
    Views:
    150

    Headspace sampling was studied for GC-MS measurements. A quick, direct method was developed for the measurement of petrol, gasoline and volatile organic solvent contamination of soil. According to our results this method is suitable for quick qualitative analysis of VOC contamination of soil, and helps to make decisions about further measurements. We concluded that an accurate quantitative measurement is not possible.

  • Germination and sugar content alteration in maize grain caused by Fusarium contamination
    42-44
    Views:
    74

    Healthy and Fusarium affected ears were collected in Fészerlak, Somogy County at the end of vegetation cycle of maize (25-30 August). Each pattern contains 25-25 ears. We compared the samples on the basis of visual image of Fusarium affection. The ears were shelled and two 0,5 kg samples were formed: healthy and Fusarium contaminated. After surface sterilisation the uniform sized seeds were soaked in sterile distilled water for 24 hours and there were germinated for 7 days. The α-amylase activity was measured with Phadebas- α-amylase test. Seeds were extracted one by one three times under reflux using 10 cm3 boiling water for 15 minutes. During our investigation germinating activity was detected to measure glucose, fructose, sucrose content and α-amylase activity. In the first seven days of germination the highest values were detected in control seeds followed by the affected seeds. Our results clearly show that stress conditions applied altered not only the saccharide content but decreased their germinating activity as well in the case of maize grain.

  • A tárolási feltételek hatása a kukorica Fusarium fertőzöttségére és toxin szennyezettségére
    28-32
    Views:
    289

    Corn samples harvested in 1997, 1998 and 1999 from different soil types were stored at different conditions (temperature, moisture content, state of kernels) for six months. The Fusarium contamination was examined by plate dilution method and the amount of mycotoxins (F-2, T-2, HT-2, DON, DAS) were determined applying HPLC method immediately after harvesting and in the third and sixth month of storage. The aim of our study was to find correlation between the ecological factors, storage conditions and the examined parameters mentioned above, as well as to prove them statistically. According to the examinations carried out after harvesting we could state that the soil type had no effect on the parameters. Analysing the effect of the years we found considerable differences. The Fusarium infection of corn samples in 1998, while the toxin contamination in 1999 was the highest. The results of storage experiment show that year (number of microscopic fungi, F-2, T-2, HT-2, DAS and total toxin content) and moisture content of kernels (F-2, T-2, and total toxin content) have a significant effect on the examined parameters. We could prove the effect of temperature on the T-2 content (samples with natural moisture content) and DON content (samples with 14% moisture content). Higher values were found at higher temperature storage. The ratio of damaged kernels influenced the DON concentration in the non- wetted samples and the number of microscopic fungi in the wetted samples.

  • Mycotoxin contamination in maize triggered by arthropod pests and the related protection possibilities
    59-64
    Views:
    162

    Mycotoxin contamination in harvested maize has increased in the last decades, which can be unequivocally back to the plant health troubles caused by global warming. The increasing of wounds in maize crops was occurred by climate change both on direct (hailstorm) and indirect
    (newly appeared pests) ways. In additional, the settling phytopathogenic microfungi on these plant wounds inflict serious human and animal health problems.
    The changing of Hungarian arthropod pests assemblages stand in the background of this dangerous nuisance complex. The spreading of European corn borer (Ostrinia nubilalis Hbn.) bivoltine ecotype as well as the newly appeared adventive species [cotton bollworm Helicoverpa armigera Hbn.), western corn rootworm (Diabrotica v. virgifera LeConte), fourspotted-sapbeetle (Glischrochilus quadrisignatus Say)] in Hungary can be responsible for this situation. In total, all technological elements, which obstruct the damage of these chewing mouthparts pests, as well as moderate the mechanical damage of maize, can be contribute to the reduction of both these phytopathogens injuries and mycotoxin contaminations.

  • The roles of mycotoxins in cereal crops production: A comparative study of Hungary and Tanzania
    151-159
    Views:
    242

    Although Hungary and Tanzania's climatic, soil, and technological conditions differ significantly in crop production, cereals crop cultivation is of paramount importance; maize crop dominates the cultivated area (Hungary 1 million ha, Tanzania 3 million ha) both from a feed and food point of view. Unfortunately, in both countries, fungal species (Fusaria, Aspergilli, Penicillia, etc.) that produce various mycotoxins on cereals, including maize grains, are a growing concern. The situation is complicated because these fungal species and their toxins can appear not only on cereals but also on other crops. Despite the prevalence of mycotoxins in both countries, studies show higher exposure risks and contamination above tolerable levels for human consumption in Tanzania to Hungary, with Tanzania observing acute aflatoxicosis.

  • Potential use of bamboo in the phytoremediation in of heavy metals: A review
    91-97
    Views:
    357

    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.

  • Molybdenum - accumulation dynamics of cereals on calcareous chernozem soil
    81-85
    Views:
    139

    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.

  • The Role of Trichoderma in the Rhizosphere of Tomato Plants
    67-69
    Views:
    73

    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.

  • Comparative analysis of sample preparation methods to determine the concentration of arsenic in soil- and plant-samples
    167-170
    Views:
    200

    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.

  • Classification of a diffuse heavy metal polluted mining site using a spectral angle mapper
    119-123
    Views:
    128

    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.

  • Studies on the Suitability of Different Mould Media Compositions for the Mycological Evaluation of Hay Samples
    34-38
    Views:
    85

    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.

  • Violation prooxidative-antioxidant stability at maize shoots at different level of accumulation of cadmium and nickel
    89-94
    Views:
    75

    Joint influence of cadmium and nickel was investigated on the feature of their accumulation by the vegetative organs of 10-days' old maize shoots. It was established that most intensively noted metals are taken in by the roots of shoots in the first 7 hours stressing influencing, while in leaves they appear only after a 7-hour long exposition. It was stated that the absorption process of the noted metals by a root system is carried by two-phase character. The indexes of inner-tissue contamination are calculated. Activating by the cadmium and nickel ions of lipid peroxidation as marker of the stressing influencing, and also was shown the proper increase of intensity of functioning of ascorbate peroxidase as the antioxidant enzyme protection of cell.

  • Plant production possibilities on a heavy metal contaminated soil with the purpose of biorefinery
    215-222
    Views:
    126

    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.