Tomáš Tóth

Human exposure to heavy metals and possible public health risks via consumption of wild edible mushrooms from Slovak Paradise National Park, Slovakia

The contamination level of 92 samples (12 species) of wild edible mushrooms and underlying substrates with heavy metals (Cd, Cu, Hg, Pb and Zn) in the Slovak Paradise National Park that borders with a region of historical mining and processing of polymetallic ores, were determined. The collected samples were analyzed using of atomic absorption spectrophotometry. The metals were determined separately in hymenophore (H) and rest of fruit bodies (RFB). Bioaccumulation factor as well as ratio of metal content in H and RFB were calculated. Cadmium and lead contents in hymenophore exceeded statutory limits of the EU (Cd: 0.5 mg/kg dry weight (dw), Pb: 1.0 mg/kg dw) for edible mushrooms in 96% and 83% of the samples, respectively. The risk from the consumption of the collected mushroom species was calculated based on the provisionally tolerable weekly intake (PTWI) values, and the highest health risk arising with consumption of particularly Macrolepiota procera, Marasmius oreades and Russula vesca from the observed area was demonstrated. It was shown that average weekly consumption of tested mushrooms species results the threat of exceeding of PTWI limits in the case of cadmium values (by 164%, 86% and 4% of PTWI for M. oreades, R. vesca and R. puellaris, respectively) and of mercury (by 96% of PTWI for M. procera) but not lead.

Phenolic compounds, antioxidant activity and Cu, Zn, Cd and Pb content in wild and cultivated cranberries and blueberries

The aim of this study was to determine the content of Cu, Zn, Cd and Pb and the total polyphenol (TP) content as well as the total antioxidant capacity (TAC) in wild cranberries and blueberries collected from different localities of the Slovakia and to compare them with properties of six cranberry and six highbush blueberry cultivars obtained from the research centre. Compared with cultivated cranberries (Cu, Zn, Cd and Pb content: 0.642, 1.496, 0.015 and 0.050 mg/kg FM) in wild fruits, higher Cu (by 37%) and lower Zn, Cd and Pb (by 8%, 7% and 44% respectively) were determined using atomic absorption spectrometry method. In wild blueberries, higher Cu, Zn and Pb (by 16%, 209% and 80% respectively) and similar Cd contents were determined compared with cultivated fruits (Cu, Zn, Cd and Pb content: 0.483, 0.541, 0.003 and 0.055 mg/kg FM). The TP contents estimated by spectrophotometry using Folin–Ciocalteau reagent were in intervals 1405–3161 (cranberries) and 1300–3077 (blueberries) expressed as mg GAE/kg FM. While the average TP content determined in wild cranberries was by 31% lower than that in cultivated cranberries, in wild blueberries it was by 97% higher compared with highbush blueberry cultivars. The values of TAC determined by spectrophotometry method using 2,2-diphenyl-1-picrylhydrazyl were in range 20.67–22.22 (cranberries) and 14.03–24.79 (blueberries) expressed as mmol TE/kg FM. In wild cranberries and blueberries, the lower average TAC values compared with cultivated berries were determined (by 1% and 28%, respectively).

Gluten-free bread with an addition of freeze-dried red and purple potatoes as a source of phenolic compounds in gluten-free diet

Abstract The basis for gluten-free diet is often gluten-free bread, which is usually characterized by a low-nutritional value, and lacks any pro-health properties. Only after an introduction of gluten-free raw materials, containing high level of bioactive compounds it would be possible to obtain the product with a pro-health potential. The aim of the study was to analyze the content of bioactive compounds (total phenolic content, phenolic acids, flavonoids, flavonols, anthocyanins and carotenoids) in gluten-free bread prepared with 5% addition of freeze-dried red and purple potatoes as well as to assess their antioxidant potential. Summarizing, among the analyzed gluten-free breads with an addition of freeze-dried red and purple potatoes, the best results could be obtained by using variety Magenta Love (red potato), which provided the highest levels of phenolic compounds and carotenoids and also antioxidant and antiradical activity.

Detection of selected trace elements in yogurt components

ABSTRACT The objective of this study was to determine the concentrations of Cu, Cd, Pb, Mn, Cr, Co, Ni, Zn, and Hg in the white and fruit parts of commercially available yogurts (n = 30) from Nitra markets (Slovak Republic). The results were correlated to determine their relationships. Three yogurt fruit flavors were chosen and tested, strawberry (n = 10), blueberry (n = 10), and cherry (n = 10). The elements were analyzed using atomic absorption spectrophotometry. Higher concentrations of toxic elements, such as Cd and Pb, were found in the fruit parts of the yogurt, and in some cases, the tolerable limit was exceeded. The white part of the yogurt was not contaminated by toxic elements. White yogurt is a good source of nutrients for humans, but the fruit part in yogurt requires detailed monitoring and improvements in the processing techniques.

Resistance in bacteria and indirect beta-lactamase detection in E. coli isolated from Culex pipiens detected by matrix-assisted laser desorption ionization time of flight mass spectrometry.

ABSTRACT The aim of this study was detections of antibiotic resistance and resistance mechanism in bacteria isolated from mosquitos (Culex pipiens) living near humans. Therefore, antibiotic resistance in bacteria isolated from Culex pipiens was investigated by disk diffusion test and MIC E-test in this study. MALDI-TOF mass spectrometry was used for detection of resistant mechanism. In this study, hydrolytic breakdown products after a few hours of incubation of the bacteria isolated from Culex pipiens were detected. Results show that enzymatic destruction of ampicillin by beta-lactamases is able to be detected by MALDI-TOF mass spectrometry from wild strains of potential pathogens. The MALDI-TOF mass spectrometry is useful method for routine detection of beta-lactamases resistant mechanism, but overnight incubation of pure culture is necessary. The results are important for proper and fast intervention to limit the spread of beta-lactamase-producing wild bacteria and provide information for appropriate initial therapy of the infections caused by these microbes.

Effect of grape seed extract on quality of raw-cooked meat products

In the present study we aimed to evaluate the oxidative stability of Spis frankfurters after application of grape seeds extracts (Blauburger + Cabernet Sauvignon and Danube) in amount of 10 mL.kg -1 during 12 days of their storage at 4 °C. Sensory evaluation of Spis frankfurters was carried out after 4 days of storage by 6-point ranking system (Surface appearance and color, appearance and color when cut, texture, aroma and flavor). It was found that sensory quality of Spis frankfurters was not significantly ( p >0.05) affected by application of grape seed extracts. Oxidation stability of Spis frankfurters after 12 days of storage at 4 °C was positively influenced ( p ≤0.05) only in the group with addition of extract made from grape seed Blauburger +Cabernet Sauvignon. This may probably related with the higher antioxidant activity of extract of this variety (100.5%) compared to an extract made from grape seed variety of Danube (55.8%). Also, it was not found significant differences ( p >0.05) of antioxidant activity between extract made from grape seeds variety Danube compared with the control group. Normal 0 21 false false false SK X-NONE X-NONE

Evaluation and comparison of the content of total polyphenols and antioxidant activity in garlic (Allium sativum L.)

Garlic ( Allium sativum L.) is one of the oldest cultivated plants in the world and highly valued throughout the ages as a culinary spice. It is a hardy perennial belonging to the Alliaceae family. The garlic bulb is the most commonly used portion of the plant, composed of 5 - 20 individual. It is a very good source of manganese, selenium, vitamin C and vitamin B6 (pyridoxine). In addition, garlic is a good source of other minerals, including phosphorous, calcium, potassium, iron and copper. Many of the perceived therapeutic effects of garlic are thought to be due to its active ingredient allicin. This sulphur-containing compound gives garlic its distinctive pungent smell and taste. Garlic possesses antiviral, antibacterial, anti-fungal properties allowing it to stand against all infections. This work has focused on the evaluation and comparison of total content of polyphenols and antioxidant activity in five varieties of garlic - Mojmir, Zahorský, Lukan, Havran and Makoi. Samples of plant material were collected at the stage of full maturity in the area of Nitra. The total content of polyphenols was determined using the spectrophotometric method of Folin-Ciocalteu agents. Determined the content of total polyphenols in garlic were in the range 621.13 mg.kg -1 (Zahorský) to 763.28 mg.kg -1 (Havran). Total polyphenols content in garlic declined in the following order: Havran >Mojmir >Makoi >Lukan >Zahorský. Antioxidant activity was measured by the spectrophotometric method using a compound DPPH (2.2-diphenyl-1-picryhydrazyl). Statistically significant highest value of antioxidant was recorded in 20.22% (Mojmir) and the lowest value was in 13.61% (Zahorský). The values of antioxidant activity observed in the varieties of garlic may be arranged as follows: Mojmir >Havran >Lukan >Makoi >Zahorský. In all the analysed varieties of garlic was confirmed by the strong dependence of the antioxidant activity and the total content of polyphenols.

Herbicidal effect in relation to the accumulation of macroelements and its regulation by regulators of polyamine synthesis.

Stress effects of triazine herbicide on cumulating of important macroelements (phosphorus, potassium, calcium and magnesium) into the grain of barley variety Kompakt, as well as the elimination of its negative effect through the addition of regulators of polyamine synthesis (γ-aminobutyric acid and propylenediamine) were investigated in pot trial. These morphoregulators are degrading products of polyamines and hypothetically after foliar application they should support their biosynthesis which increased level act against stress in plants. Application of the herbicide alone in comparison to control variant reduced the contents of all mentioned macroelements in grain of barley and also in variants, where the mixtures of herbicide with regulators of polyamine biosynthesis were applied, also the values of contents of all macroelements (except of magnesium) in barley grain were reduced (in comparison to this variant). It could be summarized that the presence of regulators in mixtures with triazine herbicide in comparison to control variant had not positive effects on contents of these biogenic elements in grain. By the comparison of variant with the applied herbicide with variants, where also regulators of polyamine synthesis were applied, there was the most positive influence of these mixtures of morphoregulators on statistically non-significant accumulation of phosphorus into generative organs of spring barley and in the case of positive accumulation of magnesium into these plant tissues there was statistically significant relation only after application of mixtures of herbicide with propylenediamine. Positive influence on accumulation of calcium was evaluated only after using of mixtures of herbicide with propylenediamine (statistically significant relation was recorded at the dose 29.6 g.ha -1 ).

The heavy metals content in wild growing mushrooms from burdened Spiš area

In this work, we evaluated the rate of entry of heavy metals into the edible parts of wild mushrooms, from central Spis area. The area is characterized by extremely high content of heavy metals particularly mercury in abiotic and biotic components of ecosystems. The toxicity of heavy metals is well known and described. Known is also the ability of fungi to accumulate contaminants from substrates in which mushrooms grow. We have collected commonly consumed species of mushrooms ( Russula vesca., Macrolepiota procera, Lycoperdon pyriforme, Lecinum piceinum, Boletus reticulatus ). Sampling was conducted for two years 2012 and 2013. The samples taken mushrooms and substrates on which to grow, we determined heavy metal content (Cd, Pb, Cu), including total mercury content modified by atomic absorption spectrometry (AMA - 254). In the substrate, we determined the humus content and pH value. The heavy metal content in soils were evaluated according to Law no. 220/2004 Z.z The exceedance limit values of Cd, Pb, Cu and Hg was recorded. Most significantly the respective limit was recorded in soil samples in the case of mercury. The determined concentration Hg was 39.01 mg.kg -1 . From the results, we evaluated the degree of ability to bioaccumulate heavy metals different kinds of fungi. We also evaluated the health safety of the consumption of these fungi on the comparison with the limit values provided in the food code of SR. We recorded a high rate of accumulation of mercury in the species Boletus reticulatus and Macrolepiota procera. For these types we recorded the most significant than allowed concentrations of mercury in mushrooms. The highest recorded concentration reached 17.64 mg.kg -1 Hg in fresh matter. The limit value was exceeded also in the case of copper. We do not recommend to increased consumption of wild mushrooms in the reference area.

Evaluation and comparison of the content of total polyphenols and antioxidant activity of selected species of the genus Allium

The species of the genus Allium are very important crops for human health. They contain many health beneficial substances, such as polyphenols (especially flavonoids), sulphur compounds, vitamins, mineral substances and substances with antioxidant activity. This work has focused on the comparison of total phenolic content and antioxidant activity of selected species of the genus Allium – garlic (Allium sativum L.), chives (Allium schoenoprasum L.), ramson (Allium ursinum L.) and red, yellow and white onion (Allium cepa L.). Samples of plant material were collected at the stage of full maturity in the area of Nitra. Total polyphenols content was determined using the spectrophotometric method of Folin-Ciocalteu agents. Determined the content of total polyphenols were in the range 444.3 - 1591 mg*kg-1. Total polyphenols content in the observed crops declined in the following order: chives > red onion > garlic > yellow onion > ramson > white onion. Antioxidant activity was measured by the spectrophotometric method using a compound DPPH (2.2-diphenyl-1-picryhydrazyl). Determined the value of antioxidant activity ranged 12.29 – 76.57%. Antioxidant activity observed in crops declined in the following order: chives > ramson > red onion > yellow onion > garlic > white onion. In all the analysed crop plants was confirmed by the strong dependence of the antioxidant activity and the total content of polyphenolic substances.