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The primary objective of this paper is to study the interspecific variation of ¹⁵N natural abundance in two dominant conifer tree species, Scot pine (Pinus sylvestris L.) and Norway spruce (Picea abies L. Karst) in a N-limited mixed boreal coniferous forest in southern Finland. Both a mature tree stand (a natural forest stand) and a stand of seedlings in a clear-cut area were considered. We analyzed %N and δ15N natural abundance in needles, branches, litter and soil of the both above-mentioned stands. Pine needles had higher N concentrations than spruce needles, both in mature forest (pine = 1.09%, SE ± 0.02 and spruce = 0.79%, SE ± 0.02) and in the clear-cut area (pine = 1.01%, SE ± 0.07 and spruce = 0.74%, SE ± 0.04). Furthermore, pine needles were significantly more depleted in δ15N natural abundance than the spruce needles, both in the mature forest (pine = -5.6‰, SE ± 0.1‰ and spruce = -4.0‰, SE ± 0.2‰) and in the clear-cut sites (pine = -2.8‰, SE ± 0.2‰ and spruce = -2.1‰, SE ± 0.3‰). The more pronounced depletion of ¹⁵N in the pine foliage might be connected to its different fungal associates in the roots compared to spruce roots. We assume that the mycorrhizal N-uptake is very prominent at the N-limited site. After clear-cutting, needles of the seedlings and the uppermost part of soil organic layer were found to be more 15N-enriched than at the natural forest site. This was attributed to an increased level of nitrification in the clear-cut site soil.

A gradual increase of phosphorus (P) concentrations in combination with organic and mineral fertilizers was applied to clayey soils at six precise experimental field sites with different climatic conditions within the Czech Republic. Soil samples were collected after the harvest of barley. Readily available P concentrations were determined using water and 0.01M CaCl₂ extractions, mobile phosphate contents were determined using the extraction procedures Mehlich 3 and Olsen. Furthermore, P uptake by barley plants was assessed. All selected procedures showed that increasing concentrations of applied P increased the mobile and readily available P contents in soils. Phosphorus uptake by barley plants ranged between 9.00 and 14.5 kg/ha and increased P application resulted in increased P concentrations in plants. Statistical analyses were performed using the Spearman test. The closest relationship was obtained for P uptake by plants and the water extraction (r = 0.81). Significant relationships were also obtained for plant uptake and the Mehlich 3 and CaCl₂ methods (r = 0.40 and 0.36, respectively). There was no statistical dependence between P uptake and the Olsen method (r = 0.25). Regression analysis was expressed best as linear regression. The closest relationship was found for water extracts and P uptake by plants (with a determination coefficient of 65%). Determination coefficients for P uptake and other methods used were significantly lower (max. 20%).

Environmental pollution of heavy metals from automobiles has attained much attention in the recent past. The present research was conducted to study heavy metal contamination in roadside soils of northern England. Roadside soil samples were collected from 35 sites in some counties of northern England and analysed for four heavy metals (cadmium, copper, lead, zinc). Their concentrations and distributions in different road verge zones (border, verge, slope, ditch) were determined. Lead concentration was the highest in the soil and ranged from 25.0 to 1198.0 μg/g (mean, 232.7 μg/g). Zinc concentration ranged from 56.7 to 480.0 μg/g (mean, 174.6 μg/g) and copper concentration ranged from 15.5 to 240.0 μg/g (mean, 87.3 μg/g). Cadmium concentration was the lowest in the soil and varied from 0.3 to 3.8 μg/g (mean, 1.4 μg/g). Though the levels of heavy metals in roadside soils were higher as compared to their natural background levels in British soils, their concentrations in general, however, were below the 'critical trigger concentrations' for the contaminated soils. All the four heavy metals exhibited a significant decrease in the roadside soils with the increasing distance from the road. The border zone had the highest mean concentration of the four metals whereas the ditch zone exhibited the lowest mean concentration.

Soil infiltration capacity is one of the key factors in the soil protection against unfavourable effects of water erosion. The purpose of its measuring was to compare and evaluate the changes of the soil physical properties and of water infiltration into soil caused by different intensity of soil cultivation at two individual sites. The ploughing (PL), shallow tillage (ST), and direct drilling (NT) effects on the soil physical properties, water infiltration into soil, and soil surface coverage with the crop residua under the soil condition loamy Haplic Luvisol, with long-term growing of maize (Zea mays L.) - Agroservis, 1^st Agricultural, a.s., Višňové - and clay soil of Calcic Chernozem (Cooperative farm Klapý), were compared. Soil bulk density values in the variant with ploughing showed in the depth up to 0.20 m considerably lower values as compared with the variants shallow tillage and direct drilling. Nevertheless, in the subsoil layer the bulk density of soil in the variant with ploughing increased in comparison with other variants. The results were also confirmed by the cone index values. At the plots in Višňové the infiltration was evaluated utilising the double ring infiltrometer, and by means of the coloured water infiltration. The results revealed significant differences in the water infiltration rate at various stages of the soil loosening. The highest average values were recorded for ploughing (1.00 dm³/min). The lowest values were found for the shallow soil tillage (0.18 dm³/min). The variant with direct drilling showed values of 0.53 dm³/min. The coloured water infiltration evaluation showed a different character of water flow in soil. The variant with ploughing showed water saturation in the top layer, the variants with reduced tillage were characterised by vertical macropores and crack effects with the water drain into deeper layers. Ploughing proved its advantage for the short-term rainfall retention. Similar results were also brought in the evaluation on the plot with clay soil (Klapý). The loosening effect was evident during coloured water infiltration in the period of snow thawing. The loosed soil layer showed a significantly higher soil water holding capacity as compared with variants with reduced soil tillage. The result showed major differences in the water infiltration rate into soil and different characters of water infiltration into soil at different soil tillage.

The objective of this study was to assess the impact of vegetation on the hydraulic conductivity of sandy soil at the locality Mláky II at Sekule (southwest Slovakia). The measurements were taken on the surface of a meadow (Meadow site), a 30-year old Scots pine (Pinus sylvestris) forest (Forest site) and a glade (Glade site). In the glade, the measurements were also taken in the depth of 50 cm (Pure sand) to reduce the influence of vegetation on the soil properties. It was found that the unsaturated hydraulic conductivity k_r(-2 cm) as reduced due to the soil water repellency increased in the same order: Forest soil < Glade soil ≈ Meadow soil < Pure sand, similarly as decreased the water drop penetration time t_p: Forest soil > Glade soil ≈ Meadow soil > Pure sand, which could refer to an inverse proportionality between the capillary suction and hydrophobic coating of the soil particles. The saturated hydraulic conductivity K_s increased in the following order: Meadow soil < Glade soil ≈ Forest soil < Pure sand; more than two-times higher K_s at both the Forest and Glade sites than that at the Meadow site could be the result of both the patchy growth of vegetation with some areas of bare soil at the Glade site and the macropores (dead roots) in more homogeneous humic top-layer at the Forest site. The share B_r of flux through the pores with radii r longer than approximately 0.5 mm decreased in the order: Forest soil » Meadow soil > Glade soil » Pure sand, revealing the prevalence of preferential flow through macropores (dead roots) in the Forest site and a negligible share of macropores in the Pure sand.

Desorption of Cu and low molecular weight dissolved organics are the primary factors that impact fate and transport of Cu in soils. To improve predictions of the toxicity and threat from Cu contaminated soil, it is critical that time-dependent desorption behaviour be understood. In this paper, the effect of organic ligands citrate and succinate on the kinetics of Cu desorption from contaminated soils varying widely in soil characteristics was investigated at three different temperatures. The results showed that the first order equation adequately described the kinetics of Cu desorption from clay and sandy soils under isothermal conditions. The reaction rate constant (k_d) values of the first order kinetic equation for Cu desorption increased consistently with temperature, indicating faster release of Cu at higher temperatures. The Cu desorption rate from the studied soils at all three temperatures was as follows: citric > succinic. The E_avalues indicates that Cu desorption from the studied soils in the presence of two organic ligands is a diffusion controlled reaction. The negative values of ΔH* suggest that the desorption reactions are not energy consuming process. The higher negative values of (ΔH*) for Cu desorption from the studied soils in the presence of succinic ligand indicate that the heat energy required to overcome the Cu desorption barrier was greater than that for Cu desorption in the presence of citric ligand. Computation of the free energy of activation (ΔG*) yielded values ranging for 87 to 87.9 kJ/mol. The largest value represents ΔG* for Cu desorption for clay soil in the presence of succinic acid while the lowest value represents ΔG* for Cu desorption for sandy soil in the presence of citric acid. The information in this study is quite necessary to construct full functioning models that will help scientists to better understand mobility and bioavailability of metals in soils.

The effect of a daily dose of 14 mg atrazine and/or 2.5 mg zearalenone that were administered to rats during 5 days of estrous cycle on the number of receptor binding sites for 3H-estradiol in uterine cytosol was investigated. Comparison with a control group of animals showed no effect of atrazine influence on the number of receptor binding sites for 3H-estradiol in the rat uterine cytosol until day 6 of the experiment, when a significantly lower value was recorded (P < 0.05). In the group of animals administered zearalenone, a decline in the number of receptor binding sites for 3H-estradiol in uterine cytosol was observed. On day 4 of the experiment, the number of binding sites was significantly greater (P < 0.05) in this group than in the control group of animals, whereafter it gradually decreased to a significantly lower value (P < 0.05) as compared to the control group on day 6. In the group of animals administered a mixture of atrazine and zearalenone, the number of receptor binding sites for 3H-estradiol in uterine cytosol did not decrease but showed a similar pattern as in the control group of animals, however, at a statistically significantly (P < 0.05) higher level.

An episode of mortality in waterbirds occurred on a sedimentation reservoir with effluents from the sugar beet processing plant at Hrusovany n.J. (South Moravia, Czech Republic) in summer 2003: tens of black-headed gulls (Larus ridibundus), several lapwings (Vanellus vanellus), one little ringed plover (Charadrius dubius), one ruff (Philomachus pugnax), one wood sandpiper (Tringa glareola), and two avocets (Recurvirostra avosetta) died. One of the two avocets and the plover, local breeders, were examined and found positive for Clostridium botulinum type C toxin by use of the toxin-neutralization test. Avocet is classified as a rare bird species according to Red Book data and is listed as critically endangered species in theCzechRepublic, and is therefore protected. Avian botulism can occasionally cause deleterious effects to waterbird fauna and its protection.

The objective of this study was to investigate the development of rumen mucosa and the level of plasma IGF-1 in calves induced by different amounts and types of milk replacers and solid diet. Forty-five male Holsteincalves 7 days of age were assigned to three groups: group I milk free replacer, late weaned; group II milk free replacer, early weaned, and group III milk replacer, early weaned. All animals received additional concentrate, water and maize silage were offered ad libitum. In each group, three calves were slaughtered at 41 days of age. The concentration of ruminal total SCFA and the molar proportion of butyrate did not differ between the groups, but the molar proportion of acetate was lower (P = 0.01) and the proportion of propionate was higher (P = 0.02) in early weaned calves. Compared to the late weaned calves (group I) the length, width and surface of the papillae of atrium ruminis, the length and width of the papillae of ventral ruminal sac and the length of the papillae of ventral blind sac were greater (P < 0.05) in the early weaned calves fed low amounts of milk and high amounts of concentrate (group III). Furthermore, there was a tendency of plasma IGF-1 concentration to be increased (P = 0.1) in early weaned calves. The plasma levels of glucose and insulin were decreased (P < 0.01, and P = 0.03, respectively). Positive correlations existed between papillae length and plasma IGF-1 concentrations (P < 0.10). Insulin and glucose concentrations were negatively correlated with parameters of papillae development (P < 0.1). In conclusion, the development of rumen papillae was stimulated in calves consuming increased amounts of concentrate. The effect was not correlated with the molar proportion of butyrate, but with the molar propionate proportion in the rumen and with the plasma IGF-1 concentration

Mononuclear cells from rabbit bone marrow were cultured for 14 days in cell-free medium for hematopoietic cells together with iron oxid nanoparticles, and then they were processed by technique for free cells for TEM (transmission electron microscopy). Staining with turnbull blue was used for the detection of iron using a light microscope. It was shown that iron nanoparticles were incorporated into the cytoplasm of mononuclear cells during 14 days cultivation. Here they were localized within different sized vacuoles with distinct membranes.

The aim of the study was to assess the ability of recovery in common carp after nitrite poisoning and to distinguish the difference in nitrite poisoning of carp at two different chloride concentrations in water. Two groups of carp (group 1 and 2) were exposed to environmental nitrite concentration of 1.45 mmol/l NO₂^- at different chloride concentrations (group 1: 0.31 mmol/l Cl^- and group 2: 3.73 mmol/l Cl^-) for 48 hours. After that, they were transferred into nitrite-free water. In the group 1 mortality of 51% occurred during nitrite exposure and further 11% mortality was observed after 24 h in nitrite free water. No mortality occurred in group 2 and control. Nitrite and methaemoglobin concentrations (MetHb) markedly increased in group 1 (plasma: 10.5 ± 1.90 mmol/l NO₂^-, liver: 3.5 ± 1.15 mmol/kg NO₂^-, muscle: 1.5 ± 0.37 mmol/kg NO₂^-, and MetHb: 93 ± 6.1%) compared with control (plasma: 0.05 ± 0.04 mmol/l NO₂^-, liver: 0.02 ± 0.01 mmol/kg NO₂^-, muscle: 0.04 ± 0.01 mmol/kg NO₂^-, and MetHb: 3 ± 2.9%). After 24 h in nitrite-free water, the values mildly decreased but not significantly (plasma: 5.1 ± 1.49 mmol/l NO₂^-, liver: 1.8 ± 0.65 mmol/kg NO₂^-, muscle: 0.8 ± 0.23 mmol/kg NO₂^-, and MetHb: 84 ± 11.2%). After next 120 h the values decreased significantly and were compared with those found in the control group (traces of nitrite, MetHb: 3 ± 2.1%). Nitrite exposure caused also increase in plasma K⁺ (3.8 ± 0.29 mmol/l), ammonia (230 ± 92 µmol/l), urea (1.7 ± 0.28 mmol/l) and uric acid concentration (66 ± 54 µmol/l) in group 1. On the other hand, values of haematocrit, erythrocyte count and haemoglobin concentration were markedly lower than control values. Most changes were corrected by the end of the recovery period, only plasma potassium concentration dropped bellow the control values. Nearly no changes were found in the group 2 compared with the control during the whole experiment duration. This shows the positive effect of chlorides on the fish resistance against nitrites.

To determine the countryside, different criteria can be used from the simplest one - the population density - to more complex ones like the economic indicators or the combination of factors characterizing the particular types of municipalities or regions. Generally, it is possible to divide these indicators into subjective and objective ones and further to categorize them according to other properties. The objective of this article is to collect as much information as possible about the methods of defining the borders of rural areas used in the Czech Republic and to set these criteria into a system. We would like to evaluate the applicability of these criteria and to state the advantages and disadvantages of their use. The article also compares statistical data related to the selected features characterizing countryside.

The paper focuses on rural immovable cultural heritage as a part of the infrastructure for certain forms of tourism. Using the secondary analysis method, it compares data about the support of rural cultural heritage in the pre-accession period (2002) and after the Czech Republic joined the EU (2004-2006). Conclusions include a broader issue of animation of cultural heritage for the purpose of rural development.

Tax harmonization in the European Union has the greatest development in the field of value added taxation, but differences still can be found. Those differences influence not only the farming business. The paper is aimed on five European Union member states - Czech Republic, Poland, Romania, Slovak Republic and Hungary. Based on the European Union regulations in the field of value added tax and the practical experience during its application, it is possible to identify the critical areas and to contribute to its correction and to provide the value added tax neutrality and efficiency on the European Union territory.

www technologies are developing very fast. The new technologies make possible the easier creation of the web applications, which support business activities. Small and medium size enterprises, which serve as the driving force for innovations and thus for economic development, can utilize these technologies for the creation of relatively inexpensive applications, which can be tailor-made for the given enterprise by using the open source software (OSS). This contribution presents several practical examples of how to create - update - the web site of an enterprise and how to supplement it with an e-shop option. Examples from the area of flower selling have been selected.

The common denominator of all rather different names and understandings of it (the problem of the "model of man and society development", problem of the "lack of the civilisation concept" etc.) is that there is no clear understanding regarding the question of the perspective approach (or approaches), the relevant basic development trends of humankind in the material as well as non-material sphere, i.e. in the basic question of many philosophers "Who are we, whence and where are we going". We mention only some of the problems, which are at present directly connected to the "problem of the future of man". These are the problems from the sphere of all-human social, ethical, humanitarian and cultural aspects of the human civilisation development, which are today (but need not be already in the near future) in the centre of attention: the problem of social inequality extension, the problem of spreading epidemics and drug abuse, the problem of the uncontrollable migration and city agglomerations growth, the problem of terrorism.

The article is focused on the importance of using the variant calculation methods in the management of companies' performance under the conditions of multifunctional agriculture. It mentions the difference between the calculations formed for the needs of valuating the production in the financial statements and the managerial calculations. Attention is paid to overhead costs in agriculture, their development is depicted with tables and graphs. The development of overhead costs during the time period of 1997-2006 is presented in crop production and outputs of wheat and rapeseed, in livestock production in Slovakia and in the outputs of cattle (6-24 months) and pigs (1-12 months). The fastidiousness of market environment of the globalized economies requires a gradual transformation from the classical calculation system into the managerial calculation system, which provides a multidimensional insight into the product as well as the market. The sequence of establishing the variant calculation methods is also introduced together with the reasons of under-valuating calculations in the managerial practice.

The objective of this paper is to show the mediation between citizens and political power by political parties in Czech rural areas. The position of political parties in rural municipalities is demonstrated in two perspectives. The top-down perspective is based on the distribution of several tens of thousands mandates in local municipal councils between political parties. The opposite perspective provides the bottom-up point of view - from the level of the individual municipalities, their party systems and party organisational structures. The analysis of the municipal election results reveals clearly that the role of political parties in local politics depends namely on the size of the given municipality. In this sense, the Czech Republic represents a very interesting example as it is characterised by a dense and heavily fragmented population settlement with a large number of small rural municipalities. In rural municipalities, we encounter incomplete party spectra and the absence of political parties in the smallest municipalities. Besides, the lists of candidates in rural municipalities reveal the weakness of the local party organisations that cannot avoid cooperating with the independent candidates. The small distance between the citizen and the elected body in a rural community significantly determines the forms of the local politics; the ideological and party mediation is superfluous, in fact, it is often seen as something harmful which divides the rural community.

The article starts with the theoretical definitions of various concepts (rural space, endogenous approach to the rural development, the actor operating in the particular locality for its development). Concerning the know-how of the rural/local actor, the information acquired also through extension service takes important position there. The methodological approach explains the use of sociological methods and techniques employed in research in two localities. This is continued by the analysis of the data gathered. The conclusions of the paper evaluate the knowledge from the group interviews and discuss the necessity of establishing an "institute" the task of which would be to provide and roof the extension service and the sufficient information level for the local, often rural actors. These actors then would use such information/extension service not only for a more efficient development of their localities, but also for a higher valorisation of their efforts in the "animation" of the rural localities.

Since 2004, the basic document which has governed liability for damage to the natural environment in the European Union is the Environmental Liability Directive No. 2004/35/EC, as amended by the subsequent regulation No. 2006/21/EC. The main purpose of the legislation was to ensure that the entity responsible for the damage pays all costs for rectifying its consequences. If it concerns damage to natural environment, the operator must undertake measures for rehabilitation, replacement and regeneration of the damaged natural resources. The primary replacement, which returns the damaged natural resources to their original state, may be differentiated from complementary replacement as compensation in the case in which the primary replacement has not provided an adequate reparation, and finally compensatory replacement - compensation for the temporary loss of natural conditions. This paper aims at an analysis of the possible means for eliminating risks due to the liability for environmental damage caused by the actions of an operator whose activities potentially threaten natural environment and may cause the biodiversity damage. Risks are assessed with regard to the risk insurability criteria for potential damage to the natural environment. The importance of risk management is stressed in the sophisticated form known as the Enterprise Risk Management. Risk management is becoming increasingly important as a part of the Solvency II concept, currently in preparation, whose first and second pillars accentuate risk management in financial institutions and the consistent quantification of the obvious, hidden and potential risks.

The article describes the competitiveness of Slovak agricultural and food products after the accession of the Slovak Republic into the EU. The analysis has shown that even despite the increased subsidization and full liberalisation of trade, the competitiveness of our products still needs to develop. The main reason behind this is the poor efficiency of production and the lack of innovation activities. Most agricultural commodities are profitable only because of subsidies. Processing industry is the main contributor to the worsening deficit of trade balance. Specific commodities with good sales potential in the EU market include cereals, malt, wheat flour, dairy products, live cattle and sheep meat.

This paper pays attention to and analyses two of the economic impacts of the BSE occurrence in the Czech Republic, namely the financial compensations to the farmers whose herds had been affected and the costs of animal killing and carcass disposal in the rendering plant. Between February 2001 and the end of June 2008, a total of 1 263 749 cows were examined and 28 cases of the BSE were detected. Consequently, 4 022 cows in cohorts were killed and their carcasses were safely disposed of. The farmers whose herds had been affected were provided compensations for the losses suffered. The total of the compensations in this period reached CZK 198,413 thousand. Of these, 83.3% (CZK 164.9 million) were compensations for the value of the killed animals, 9.7% (CZK 19.2 million) for the related costs, i.e., killing, safe disposal of carcasses and the examination for the BSE, and 6.9% (CZK 13.5 million) for the losses due to non-materialised production. The average costs per 1 BSE-positive animal were CZK 7.08 million and the average costs per 1 cohort animal were CZK 49 331. In the rendering plant responsible for killing the infected and cohort animals and safely disposing of their carcasses, the total of 2 221 tons of raw material was processed between March 2003 and February 2008, and this cost CZK 9 315 thousand. The fact that there were only two cases of the BSE in 2007 and none in 2008 suggests a trend towards the disease eradication, which is in agreement with the situation in the other EU countries.

This paper addresses (ex ante) the issue of the potential impact of the modulation of direct payments on a sector and regional scale in the Czech Republic. The ultimate version of the compulsory modulation measure adopted under the Health Check of the Common Agricultural Policy (CAP) assumes the reduction of direct payments if the total individual claim exceeds 5 thousand € or 300 thousand € level. The Czech agricultural sector will be impacted by this measure substantially, given the large scale farming enterprises. In 2013, the total farmers' direct payments will be cut by more than 10% (€ 91 million). Moreover, there are regional differences in farm structures (the average farm size and the extent of collectivization) which will bring about various effects of policies in the heterogeneous regions. The analysis further shows that the regions that are least affected are at the same time more environmental sensitive and are mostly situated in the mountainous or sub-mountainous parts of the country or more urban areas than the average. Hence the effect of the modulation, from a purely environmental perspective, may not contradict the objectives of other environmental policies. That is to say the regions that need support the most will be reduced the least. However, the picture is less obvious in the regional economies where more rural regions (potentially more vulnerable with socio-economic problems) tend to be more affected.

The article aims at the description and assessment of strategic options for companies which have necessary resources to take the advantage of the current economic downturn. The theoretical framework is based on two predominant approaches to competitive advantage and the practical implications for actions to be adopted are derived from the recommendations published recently by the leading consulting firms. While quick fixes ensuring a short-term survival (mostly financially based cost-saving measures) are an essential first step, a longer-term success lies in the effective adoption of the scenario-planning techniques, active competitors intelligence and a proactive attitude to restructuring through a combination of mergers, acquisitions and divestment decisions.

The paper analyses and compares the EU direct payments in the conditions of the Slovak Republic during the monitored period 2004-2006. The 2003 reform of the Common Agricultural Policy (hereafter CAP) introduces a considerable simplification of the EU producers' support and a general improvement of the market orientation of agriculture. The Slovak Republic has temporarily adopted the system of the Single Area Payment Scheme (SAPS) which is used in the old member states. The Slovak Republic can use this system until the end of the year 2010. The amount of the direct payments in 2004 was 53.1% of the EU average. The prediction for 2007 was 70% of the EU average, provided that the state co-finances 30%.

In order to develop the quality of life in small rural municipalities, their representation faces the thoughts about the perspective of these municipalities in economic terms (the capacity to finance long-term investments) as well as in the socio-cultural terms (the development of participation in public life embedded in the local identity). This article presents the results of the pilot empirical survey in one micro-region of the Czech Republic. The results of the in-depth interviews clearly indicate the preference of the investigated communities to choose the strategy of supporting their independence (which might result in the risk of lower ability to deal with economic problems) prior to the strategy to strengthen the economy of the community through merging the municipalities (and to risk the potential loss of local identity). The conclusions consider the possible forms of municipal cooperation reinforcing the capacity to address economic problems while preserving the autonomy of small rural municipalities. However, the low ability of the partnership cooperation of these municipalities is demonstrated.

Furan and its derivatives were identified in a small number of heat-treated foods back in the 60's and 70's. In May 2004, US Food and Drug Administration published a report on the occurrence of parent furan in a number of thermally treated foods. Since furan has been classified as "possibly carcinogenic to human" by IARC, a great concern has been addressed to the analysis of this substance naturally-occurring in food. This paper gives a short overview on the mechanistic pathways of the parent furan formation in food by degradation of amino acids and/or reducing sugars, and oxidation of ascorbic acid and poly-unsaturated acids which can be induced by thermal or irradiation treatments; further, it deals with the metabolism and toxicology of furan as well as with the comparison of the methods of furan determination.

Phytic acid has been considered to be an antinutrient due to its ability to bind minerals and proteins, either directly or indirectly, thus changing their solubility, functionality, absorption, and digestibility. In this study, the influence of the flour type (type 500, type 850, and whole meal flour) and three different breadmaking procedures (direct, indirect, and with sourdough addition) on phytic acid was investigated. The results showed that the flour type influenced the phytic acid content. The phytic acid contents of flour type 500, type 850, and whole meal flour was 0.4380, 0.5756, and 0.9460 g/100 g dm, respectively. The dough and bread prepared from flour with a higher phytic acid content also contained higher amount of phytic acid. During fermentation and baking, degradation of phytic acid occurred. Phytic acid was also influenced by pH. Samples of lower pH had a lower phytic acid content. Dough prepared from flour type 500 and type 850 with 10% addition of sourdough had especially low phytic acid contents, and the bread prepared from the respective dough contained no phytic acid at all.

The fractionation of Cd, Cu, Mo, Ni, and Zn species in extracts of rye (cv. Fernando) seedlings (grown up in both standard and Cd²⁺-enriched medium) and rye flour was performed by SEC/ICP-MS method. The majority of Cu, Zn, and Ni in all samples were bound in the 1-2 kDa fraction. Molybdenum occurred in all samples in the fraction of 3 kDa. During five days of cultivation in a solution of 30 µmol/l Cd²⁺, the plants accumulated as much as 5 mg/kg fresh matter of Cd, but its soluble portion represented only 12-15%. The prevailing portion of Cd complexes was contained in the fraction of 3 kDa, while the minor part occurred in the fraction of 20 kDa. The speciation of elevated Cd in plants differs from that of other metals present at a physiological level. The metal-rich fractions of the extracts of all samples (i.e. those of 1-2 kDa) were refined by immobilised metal affinity chromatography. The isolated ligands of trace elements were peptides rich in dicarboxylic aminoacids.