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Acta Alimentaria
Authors: Cs. Dobolyi, K. Inotai, I. Bata-Vidács, D. Sárkány, O. Csernus, S. Kocsubé, B. Tóth, A. Szekeres, and J. Kukolya

cereal products were collected and analysed in the UK by Leon et al. (2015) . ST was found in 4% of the investigated cereal samples at >0.5 μg kg −1 concentration, in line with the results of the wider EFSA survey of 1,142 cereal samples ( Mol et al

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Grant, C.A., Bailey, L.D., McLaughlin, M.J. & Singh, B.R. (1999): Management factors which influence cadmium concentrations in crops. - in: McLaughlin, M.J. & Singh, B.R. (Eds) Cadmium in soils and plants. Chapter 7 . Kluwer Academic Publishers

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The antioxidant effects of seafennel (Crithmum maritimum L.) essential oil and rose (Rosa canina) methanol extract at different concentrations were tested in natural olive oil stored at 60 °C, by measuring peroxide values and free oil acidity after regular intervals. All concentrations of both plant extracts showed antioxidant effect compared with control in experiments. The most effective extracts were 0.4% level of rose. The 0.2% concentrations of rose extract and seafennel oil and 0.4% level of seafennel oil followed in a decreasing order, respectively. The 0.2% level of seafennel oil in olive oil had more effect than those of only 0.02% concentrations of butylated hydroxyanisole (BHA) and butylated hydroxytoluene (BHT). Acidity values of seafennel oil at the 0.4% concentration were high compared with its 0.2% level. Acidity values of both rose concentrations were found partly similar.

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will play a vital role as a cementitious material due to the high concentration of lime and gelignite. On the other hand, because of the problems, which are occurred in the subbase layer in roads and buildings in Iraq, many ways can be adopted to

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Green synthesis of hydroxyapatite (HA) nanoparticles was followed using various concentrations of pectin extracted from the culinary banana bract. The effect of pectin concentrations on purity, crystallinity, particle size, and morphology of synthesized HA nanoparticles were studied. The extracted pectin was characterized by proton-1 nuclear magnetic resonance spectroscopy (1H NMR) and Fourier transform infrared (FT-IR) spectroscopy. FT-IR results revealed that increased concentration (0–0.075 % w/w) of pectin substantially improved the purity level of synthesized HA nanoparticles. In addition, higher concentration of pectin also reduced the crystallinity and size of the synthesized HA nanoparticles, which was confirmed by X-ray diffraction (XRD) and SEM results, respectively. The synthesized HA nanoparticles at increased pectin concentration (HA0.075) evinced high purity, less crystallinity, and discrete uniform shape. Results of TEM images have the credence to reveal the presence of nanosized discrete particles (20–50 nm) with lattice structure of hydroxyapatite.

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The analyzed samples were runoff waters from bituminous roofing. The runoff water pH was lower than that of the storm-water. First flush phenomena were observable in the samples conductivity, turbidity as well as suspended solid, dry and organic matter concentration. The reason of the phenomena is the initial dissolution of deposited aerosols and weathering products. Because of that, the roof runoff quality is affected by the dry period length. Presumably to the roof matter, the samples had high dissolved organic matter concentrations. The measured polycyclic aromatic hydrocarbon (PAH) concentration implied the dissolution of some component from the roof matter.

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The objective of this work was to assess the impact of various NaCl concentrations on Lactobacillus rhamnosus OXY viability after freeze-drying. Osmotic stress was applied during the exponential growth phase of bacterial culture. At salt concentrations between 0.2–0.5 M, a high biomass concentration and a significant increase in cell viability after lyophilisation was observed. An analysis of two-dimensional protein gels indicated the presence of shock proteins, for example, GroEL, ClpB, DnaK, TF, which provide resistance during freeze-drying and subsequent storage. On the basis of these results, it is recommended that lactic acid bacteria cultures be sub-lethally treated with 0.5 M NaCl before freeze-drying.

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The degradation process of fructo-oligosaccharides (Raftilose® P95) has been studied in apple pulp matrix at 70–80 °C in pH range 2.7–3.3. Changes of sugar compositions have been analysed by an appropriate isocratic HPLC with differential refractive index detector for oligosaccharide determination. According to Arrhenius equation significant effect of temperature has been observed on the decrease of oligomer concentration. The oligomers (DP3-DP7) degrade continuously at any pH between 2.7 and 3.3. The lower the pH the higher the change of oligomer and monomer concentration is. The oligomers (DP4-DP7) could give out in 30–40 min below pH 3.0 caused by the high concentration of protons. The rate of degradation depends not only on the processing time, temperature, and the proton concentration of the solution, but on the characteristic of apple pulp, too, where the degradation is significantly higher than that in water solution.

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In this study, the effects of different temperature, pH, salt and glucose concentrations on the planktonic growth, biofilm formation, and formed biofilm of Serratia odorifera and Serratia marcescens, isolated from traditionally made cheese, were investigated using spectrophotometric method. The investigated strains demonstrated best planktonic growth and biofilm formation in Tryptic soy broth. The limiting factors for the planktonic growth and biofilm formation were temperature below 4 °C and salt concentration above 4%. Temperature of 37 °C and 44 °C, as well as various concentrations of glucose, stimulated the planktonic growth of bacteria. Moderate influence on biofilm formation was demonstrated at 37 °C as well as at various concentrations of glucose. These results were in accordance with the origin of bacteria, since the isolates were obtained from cheese.

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The adaptation to brining conditions of 20 strains of Lactobacilli were tested. At 6% salt all strains reduced the pH to 4 in 72 h. At higher salt concentration, only some of the strains showed this ability. The ability to synthesise lactic acid was tested at different salt concentrations. Lactic acid was quantified by HPLC analyses and at halophilic conditions six strains showed good ability. The glucosidic activity tested on a synthetic compound ( p -nitrophenyl-β-D-glucopyranoside) screened the best Lactobacillus strains (20205 DSMZ, 20314 DSMZ and 104442 CIP). The ability to hydrolyse the oleuropein molecule was tested and all of the strains selected showed good activity at low salt concentration and low oleuropein content in the medium. This ability decreased drastically when the salt and oleuropein content were higher. The best strain was the 20205 DSMZ, which at low salt concentration hydrolysed more than 95% of oleuropein in 120 h.

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