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The production of Kluyveromyces marxianus biomass enriched with copper ions were studied. For that reason the growth of Kluyveromyces marxianus in whey with different concentrations of copper ions in batch process under semiaerobic and aerobic conditions were examined. The kinetics of copper ions accumulation in yeast cells, under the same conditions, as well as the reduction of chemical oxygen demand (COD) during yeast growth in aerobic condition, were monitored, as well. The concentration of copper ions in media up to 4 mg l −1 did not affect the yeast growth, whereas at a higher concentration, a marked decrease in the rate of yeast growth, ethanol production and lactose consumption occurred. In semiaerobic conditions, the maximum uptake of 0.35 mg Cu g −1 d.m. was obtained, while in aerobic conditions a lower uptake of 0.26 mg Cu g −1 d.m. and COD reduction of 85% were achieved. COD reduction was independent of the copper addition or uptake.

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Antifungal effect of Micromeria myrtifolia Boiss. & Hohen. in Boiss. and Prangos uechtritzii Boiss. Hawsskn decoctions was tested against Alternaria alternata, Aspergillus niger, Aspergillus parasiticus, Botrytis cinerea, Fusarium oxysporum f.sp. melonis and Penicillium digitatum. Of the 2 substances tested Pr. uechtritzii, being present at 75 to 80% concentration in potato dextrose agar, partly inhibited growth of A. alternata, B. cinerea and P. digitatum. Pr. uechtritzii had higher antifungal effect than M. myrtifolia on mycelial growth during incubation. M. myrtifolia partly affected mycelial growth of A. alternata and A. niger at the beginning of incubation. But the mycelial growth of F. oxysporum was not inhibited by M. myrtifolia concentrations during incubation. Also, Pr. uechtritzii did not have any affect on mycelial growth of A. niger during incubation P. digitatum, the most sensitive microorganism to both decoctions. Higher decoction concentrations of plants used in study will be probably inhibit mycelial growth of microorganisms.

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Abstract

This paper is about comparing the effectiveness of the sorbent materials of granulated activated carbon in removing of bromates from drinking water. The limit value (10 µgl−1) of bromates in the drinking water was stated by World Health Organization. In order to insure the reduced concentration of bromates in the drinking water, an experiment was performed using the batch test. In this experiment different types of sorbent materials with different properties were testing. Based on batch test were measured the parameters like the immediate adsorption capacity, the adsorption efficiency, and the concentration of bromates after the adsorption were measured at the evaluated time.

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Abstract

The main goal of this study is firstly to model the phenomenon of advection and diffusion of the gaseous residues of coal combustion. On the other hand, to study the dispersion of this pollution by varying the parameters like the wind and the resources of pollution, where there are four emissions: SO2, CO, NO2 and PM10. The present model will compare estimating concentrations with the results found by the contribution of the thermal power plant of Jerada city, where the American Environmental Regulatory Model is used. The results suggest that SO2, PM10, NO2 and CO concentration simulated by turbulent k-ε model in combination with the transport model of diluted species, at the 3h and 24h intervals, greater than their respective observed concentrations compared with the American Environmental Regulatory Model. The concentrations of the model found are very high and exceed the limit values under the study conditions. Indeed, the simulated model was used in 2D with a very low wind speed (10−4 m/s) and in the absence of gravity, hence the total neglect of altitude because the two sources of pollution are at the height of 120 m.

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A capillary isotachophoretic (cITP) method to determine the concentration of nitrates and nitrites in vegetables and lactic acid fermented tomato, cucumber and cucumber-onion juices is described. Method characteristics (selectivity, response function, linearity, precision, accuracy and limit of quantification) were determined. The minimal sample pretreatment and relatively low running make isotachophoresis a good alternative to existing methods.

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In this study honey samples of Eucalyptus honey (Eucalyptus lanceolatus) were botanically characterized. Response surface methodology was used to analyze the effect of temperature, time and pH on the quality responses (hydroxymethylfurfural concentration and diastatic activity) of Eucalyptus honey. A central-composite rotatable design was used to develop models for the responses. At the central value of time (10 min), the maximum concentration of hydroxymethylfurfural was demonstrated at the highest temperature and pH. The maximum value of hydroxymethylfurfural concentration was also obtained at the maximum time and temperature, while keeping the pH at the central value of 5.3. Diastatic activity decreased as the pH moved away from the central pH value of 5.3 to 5.6 at any level of temperature and time. Three-dimensional response surfaces were superimposed, and the overlapping regions gave the diastatic activity (calculated as diastase number 9 to 23.09 °G) and hydroxymethylfurfural concentration (3 to 10.21 mg kg-1) at 48±1 °C for 9.5±1 min at 5.15±0.15 pH.

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Alpha keto acids are important food additives, which commonly produced by microbial deamination of amino acids. In this study, production of phenylpyruvic acid (PPA), which is the alpha keto acid of phenylalanine was enhanced in 2-l bench scale bioreactors by optimizing of fermentation medium composition using the Box-Behnken Response Surface Methodology (RSM). Optimum glucose, yeast extract, and phenylalanine concentrations were determined to be 119.4 g 1−1, 3.7 g 1−1, and 14.8 g 1−1, respectively, for PPA production, and 163.8 g 1−1, 10.8 g 1−1, and 9.8 g 1−1, respectively, for biomass production. Under these optimum conditions, PPA concentration was enhanced to 1349 mg 1−1, which was 28% and 276% higher than the unoptimized bioreactor and shake-flask fermentations, respectively. Moreover, P. vulgaris biomass concentration was optimized at 4.36 g 1−1, which was 34% higher than under the unoptimized bioreactor condition. Overall, this study demonstrated that optimization of the fermentation media improved PPA concentration and biomass production in bench scale bioreactors compared to previous studies in the literature and sets the stage for scale up to industrial production.

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Herbal teas may be effective in adjuvant therapy for the prevention of complications of diabetes mellitus II. Agrimoniae herba, Betulae folium, Bursae pastoris herba, Foenigraeci semen, Galegae herba, Maydis stigma, Taraxaci radix, Phaseoli fructus sine seminibus, Urticae folium, and their teas were analysed by ICP-OES for element content. Concentration of the elements of crude drug samples obtained are in good agreement with the average concentrations of plants, although some significantly high concentration has been found for manganese (893 mg kg-1), zinc (275 mg kg-1) and iron (492 mg kg-1) in Betulae folium, for copper (41.2 mg kg-1) in Galegae herba, for iron (2692 mg kg-1) in Taraxaci radix, for calcium (41210 mg kg-1) and magnesium (6275 mg kg-1) in Urticae folium. The common characteristic feature of crude drugs is the relatively high concentration of chromium (0.8-16.3 mg kg-1). Ion concentrations of teas are relatively low. The quantities of metal ions do not cover the daily needs, nevertheless, they may be important as food supplements. According to U.S. Recommended Dietary Allowances (RDA), the following teas are good sources: Agrimoniae herba for chromium, Betulae folium for manganese, Taraxaci radix for copper and chromium, Urticae folium for potassium and calcium. The dissolution of elements from plant drugs varies: potassium (22.5-74.7%), sodium (1.9-60.5%), calcium (6.6-28.1%), magnesium (12.3-52.5%) and copper (3.7-51.4%) are readily dissolved. The dissolution of manganese (6.8-32.3%) and of zinc (0-31%) is lower. The dissolution of chromium from Agrimoniae herba (9.55%) is significantly higher, while the dissolution ranges from other plant drugs are between 0-5.9%.

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/4 807 812 Dragun Z., Roje V., Mikac N., Raspor B. Preliminary assessment of total dissolved trace metal concentrations in Sava River water, Environmental Monitoring and

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The adsorption properties of natural zeolite (clinoptilolite) has been studied in order to determine its applicability for copper and zinc removal in acid mine drainage treatment process. For purpose of these experiments the determination of the sorption equilibrium and removal efficiencies were performed under batch conditions using single and dual-component solutions. The experiments were carried out under acidic conditions (pH approx. 4). In general, the obtained results from kinetic experiments showed rapid decrease of the metal concentration during the first 10 min, corresponding to ~80% total removal of ions from both single and dualcomponent solutions. This initial rapid period was followed by a further slow drop in metals concentration caused by ion-exchange in deeper structure of zeolite.Preliminary tests on the real samples of acid mine drainage from Smolnik mine, Slovakia, showed that natural zeolite has a potential as an alternative low cost adsorptive material for acid mine drainage treatment.

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