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Jagna Chmielowska-Bąk, Inga Zinicovscaia, Marina Frontasyeva, Aleksandra Milczarek, Sabrina Micheli, Mariia Vysochanska and Joanna Deckert

Abstract

Iron (Fe) and magnesium (Mg) deficiency in human diets is a widespread problem observed in various regions of the world. Insufficient Fe uptake results in the development of iron dependent anaemia and depressed physical and intellectual performance. In turn Mg deficiency is associated with alterations in neuromuscular and cardiovascular systems. An emerging alternative to traditional supplementation of these elements in the form of pills, liquids or effervescent tablets, is introduction of fortified food products. In present study we show that preincubation of soybean seeds in Fe and Mg solutions leads to elevated content of these elements in the seedlings. Importantly the pretreatment did not affect germination rate, seedlings growth or, with an exception of Fe supplementation at highest concentration, antioxidant capacity. The obtained results indicate that preincubation of seeds in Fe and Mg solutions may be a promising method of obtaining enriched soybean sprouts.

Open access

Paweł Świsłowski and Małgorzata Rajfur

Abstract

The aim of the research was to assess the level of contamination with heavy metals (manganese, iron, nickel, copper, zinc, cadmium and lead) in two forest areas selected in different places in Poland: the first one in the Swietokrzyskie Province (forests of the Staporkow Forest Division) and the second one in the Opolskie Province (forests of the Kup Forest Division). The degree of contamination of these forest areas with analytes was found using edible large-fruited mushrooms naturally occurring there - the research was carried out using passive biomonitoring method. Heavy metals in mushrooms (separately in stems and hats) as well as in soil samples were determined by atomic absorption spectrometry with excitation in flame (F-AAS). The obtained results were interpreted by assessing the degree of contamination of forest areas on the basis of concentrations of heavy metals in mushrooms. The obtained results indicate an increased accumulation of heavy metals in hats than in mushrooms stems. On the basis of the obtained data, significant contamination of forest areas with selected heavy metals was also found. This is confirmed by the possibility of using mushrooms as biomonitors in passive biomonitoring of forest areas, which are heavy metal accumulators. In the interpretation of the test results, the phytocumuling factor (PF) was also used. The degree of accumulation of heavy metals, from given forest areas - from soil to mushrooms - was assessed on the basis of determined PF coefficients. In addition, good bioavailability of the analysed analytes by mushrooms was found. Additionally, on the basis of the conducted studies, the possibility of mushroom consumption was assessed - they are not suitable for consumption due to the fact that the permissible concentration standards of heavy metals contained in mushrooms were exceeded.

Open access

Christian Canales, Johanna Eyzaguirre, Patricio Baeza, Paulina Aballay and Juan Ojeda

Abstract

Experimental biodesulfurization (BDS) data for dibenzothiophene (DBT) (1.0-7.0 mM) with Rhodococcus rhodochorus immobilized by adsorption on silica, were adjusted with liquid-film kinetic model (Fisher coefficient, F = 592.74 and probability value p << 0.05 and r 2 = 0.97). Simulations predict the presence of considerable amounts of DBT surrounding the particles, which would be available for the cells adsorbed on the surface of silica. The greatest percentage removal (50 %) was obtained for adsorbed cell system over the suspended bacterial cells (30 %), showing that sulfur substrates are more bioavailable when the bacterial cells are adsorbed on silica. The liquid-film modelling with diffusional effects provides proper theoretical basis to explain the BDS performance obtained using adsorbed cells.

Open access

Mariusz Kuglarz and Klaudiusz Grübel

Abstract

The aim of this study was to develop an effective thermochemical method for treatment of industrial hemp, in order to increase its bioconversion to biofuels and bio-products. Industrial hemp was subjected to various thermochemical pretreatments using: alkaline (3 % NaOH), oxidative (3 % H2O2 at pH 11.5) and glycerol-based methods (70-90 % of glycerol, 1-3 % NaOH), prior to enzymatic hydrolysis with Cellic® CTec2/Cellic® HTec2 (15 FPU∙g−1 glucan). Innovative pretreatment with glycerol fraction (80 % glycerol content, 2 % NaOH, 12.5 % biomass loading) showed to be superior over commonly used alkaline and oxidative methods with respect to by-products generation and sugar losses. Integrated process of ethanol production from enriched cellulose fraction (172 kg EtOH∙Mg−1 of dry hemp) and succinic production from xylose-rich residue after ethanol fermentation (59 kg∙Mg−1 of dry hemp) allowed to convert about 97 % of sugars released (glucose and xylose) during enzymatic hydrolysis of pre-treated biomass. The present study showed that it is possible to replace 50 % of the costly yeast extract, used during succinic fermentation as nitrogen source, by alternative nitrogen source (rapeseed cakes) without significant deterioration of succinic yield. Pretreatment liquor after lignin precipitation (52 kg∙Mg−1 of biomass treated) exhibited a high biodegradability (92 %) and allowed to produce 420 m3 CH4/Mg VS). Results obtained in this study clearly document the possibility of biofuels (bioethanol, biogas) and bio-chemicals production from industrial hemp, in a biorefinery approach.

Open access

Lech Wojciech Szajdak, Wioletta Gaca, Jürgen Augustin and Teresa Meysner

Abstract

The Typic Hapludalfs soils under two old shelterbelts (200 years old) Robinia pseudacacia and Crataegus monogyna, multi species of trees (young shelterbelt - 20 years old) and neighbouring cultivated fields were investigated. The function of shelterbelts of different age and plant composition in agricultural landscape and estimation of biochemical and chemical soil conditions for the decrease of greenhouse gases release from soil to the atmosphere was the aim of the research. In soils under shelterbelts were estimated activities of several enzymes participating in the oxidation-reduction processes, ferric and ferrous ions and the evolutions of gases like N2, N2O, CO2, and CH4. The soils under old shelterbelts characterized higher peroxidase activity than in young shelterbelt and adjoining cultivated fields. However, no significant differences were observed for nitrate reductase activity between old and young shelterbelts. There were proved differences between emission of N2O in soils under shelterbelts and in adjoining cultivated fields. Furthermore, it was observed significant effect of the young shelterbelt on the decrease of carbon dioxide release than in the adjoining cultivated field. The manipulation of the landscape through the introduction of shelterbelts of different age and the composition of plants leads to the modification of biogeochemical soil conditions for N2O and N2 formation and finally decrease of the greenhouse gases evolution from soils to the atmosphere. Thus the creation of new shelterbelts is favourable factor for agricultural landscape.

Open access

Krzysztof Kupiec and Monika Gwadera

Abstract

This work refers to the modelling of heat transfer in horizontal ground heat exchangers. For different conditions of collecting heat from the ground and different boundary condition profiles of temperature in the ground were found, and temporal variations of heat flux transferred between the ground surface and its interior were determined. It was taken into account that this flux results from several different mechanisms of heat transfer: convective, radiative, and that connected with moisture evaporation. It was calculated that ground temperature at great depths is greater than the average annual ambient temperature.

Open access

Wael S. El-Tohamy, Samar N. ABDEL-Baki, Nagwa E. Abdel-Aziz and Abdel-Aziz A. Khidr

Abstract

The objective of this study is to reveal the spatial and temporal variations of surface water quality in this part of the River Nile with respect to heavy metals pioneerution. Seventeen parameters in total were monitored at seven sites on a monthly basis from October 2013 to September 2014. The dataset was treated using the tools of univariate and multivariate statistical analyses. Cluster analysis showed three different groups of similarity between the sampling sites reflecting the variability in physicochemical characteristics and pollution levels of the study area. Six PCs factors were identified as responsible for the data structure explaining 91 % of the total variance. These were eutrophication factor (23.2 %), physicochemical factor (20.6 %), nutrients (16.3 %) and three additional factors, affected by alkalinity and heavy metals, recorded variance less than 15 % each. Also, the heavy metals pollution index (HPI) revealed that most of the calculated values were below the critical index limit of 100. However, two higher values (124.89 and 133.11) were calculated at sites V and VI during summer due to the temperature and increased run-off in the river system.

Open access

Monika Janas and Alicja Zawadzka

Abstract

Industrial waste deposited in landfills poses a threat to the environment and can cause its deterioration. The physical and chemical processes that result in the formation of a number of harmful substances occur in the mass of stored waste. When released to the environment these compounds can be dangerous to all its elements, especially to groundwater. The monitoring of landfill impact plays an important role in assessing the state of the environment. It allows us to follow what changes take place in the waste bed itself, and in particular elements of the environment. On the basis of long-term monitoring studies (conducted in the years 1995-2016), the quality of groundwater around the industrial waste landfill in Zgierz was determined and its impact on the environment was characterized. The quality of conducted monitoring was assessed in relation to the current regulations. Analysis of the results of groundwater quality tests confirms that the industrial landfill in the operational phase due to a number of applied security measures has not contributed to the deterioration of groundwater quality. In the post-operational phase, groundwater contamination is observed, and consequently irreversible changes occur in the environment. The negative impact of the landfill can be due to the disruption of sealing layers and elution of pollutants from the waste by rainwater. The landfill site monitoring plays a key role in assessing causal relationships occurring between the state of the landfill and elements of the environment in its vicinity.

Open access

Sayiter Yildiz

Abstract

In this study, ANN (artificial neural network) model was applied to estimate the Ni(II) removal efficiency of peanut shell based on batch adsorption tests. The effects of initial pH, metal concentrations, temperature, contact time and sorbent dosage were determined. Also, COD (chemical oxygen demand) was measured to evaluate the possible adverse effects of the sorbent during the tests performed with varying temperature, pH and sorbent dosage. COD was found as 96.21 mg/dm3 at pH 2 and 54.72 mg/dm3 at pH 7. Also, a significant increase in COD value was observed with increasing dosage of the used sorbent. COD was found as 12.48 mg/dm3 after use of 0.05 g sorbent and as 282.78 mg/dm3 after use of 1 g sorbent. During isotherm studies, the highest regression coefficient (R 2) value was obtained with Freundlich isotherm (R 2 = 0.97) for initial concentration and with Temkin isotherm for sorbent dosage. High pseudo-second order kinetic model regression constants were observed (R 2 = 0.95-0.99) during kinetic studies with varying pH values. In addition, Ni(II) ion adsorption on peanut shell was further defined with pseudo-second order kinetic model, since qe values in the second order kinetic equation were very close to the experimental values. The relation between the estimated results of the built ANN model and the experimental results were used to evaluate the success of ANN modeling. Consequently, experimental results of the study were found to be in good agreement with the estimated results of the model.