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Acta Alimentaria
Authors: K. Jurica, I. Brčić Karačonji, D. Lasić, D. Vukić Lušić, S. Anić Jurica, and D. Lušić

Phthalates are ubiquitous environmental contaminants that, due to their lipophilicity, migrate more readily into beverages with higher ethanol content. The aim of this work was to study the occurrence of phthalates in samples during the plum spirit production and in the final product, plum spirit manufactured by registered producers from five European countries, using gas chromatography-mass spectrometry (GC-MS). A decreasing trend of mean values was observed for diethyl phthalate (DEP), di-iso-butyl phthalate (DiBP), and di-n-butyl phthalate (DBP) as the distillation process went on. Levels of benzyl-butyl phthalate (BBP) and di-(2-ethylhexyl) phthalate (DEHP) increased in the distillation phase compared to concentrations in the preceding phases. In commercial plum spirits, DEHP and DiBP were detected in the highest concentrations. Results also indicated that a moderate daily consumption of plum spirit does not pose a health risk regarding the Tolerable Daily Intake of BBP, DEHP, and DBP

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Road traffic flows in intersections are modeled in this article. Cost of CO2, CO, CH, NOx, PM and value of travel time have been used in order to estimate the social costs arising at the intersections. The article presents assumptions for constructing the mathematical model, it describes the mathematical model and gives simulation results. Traffic flow parameters, as traffic flow concentration and traffic flow speed are presented as based on real traffic data.

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Acta Alimentaria
Authors: J. Varga, R. Kiss, T. Mátrai, T. Mátrai, and J. Téren

Ochratoxin A is a mycotoxin produced by Aspergillus and Penicillium species. This mycotoxin is a common contaminant of various food products including cereal products, spices, dried fruits, coffee, beer and wine. Besides cereal products, beer and wine contribute significantly to ochratoxin exposure of humans. We examined the ochratoxin content of Hungarian wines and beers using an immunochemical technique. The detection limit of this technique is 0.01mg l-1. Altogether 65 wine and 25 beer samples were analysed. The presence of ochratoxin A was confirmed by HPLC in positive samples. Ochratoxin A was detected in 97.7% of wines, with ochratoxin concentrations ranging from 0 to 0.533mg l-1. The mean ochratoxin A concentration in wines was 0.110mg l-1. Only one of the Hungarian wines examined contained more than 0.5mg l-1ochratoxin A, the previously suggested EU limit for wine. Our data indicate that red wines are more frequently contaminated, and have higher mean ochratoxin contamination (0.117mg ml-1) than white wines (0.0967mg ml-1), in accordance with previous observations. A North-South gradient in wine ochratoxin concentrations is not evident from our data. For beers, all but one of the samples was found to be contaminated with small amounts of ochratoxin A with a mean concentration of 0.127mg l-1(range: 0.030-0.250mg l-1). Only one of the beers contained ochratoxin A above 0.2mg l-1, the anticipated European Community maximum allowable limit in beer. We could not detect correlation between the type and origin of beer and ochratoxin contamination.

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A novel screening immunoassay for histamine was used for detection of histamine in different foodstuffs. The detection limit of this assay was 20 µg kg-1. The concentration of histamine varied between 182-982 µg kg-1 in sauerkraut, cheese and fish samples and 26-18433 µg l-1 in milk, sparkling wine and wines. The applied competitive enzyme immunoassay (ELISA) seemed a reliable technique for simple and rapid determination of histamine in food.

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Acta Alimentaria
Authors: LJ. Glavaš-Obrovac, T. Opačak, V. Bareš, D. Šubarić, J. Babić, V. Ilakovac, and I. Karner

Recent studies performed on some tumour cell lines have given proof to the antiproliferative activity of compounds isolated from red wines against tumours. The purpose of this study was to evaluate potential cytotoxic activity of different concentrations of selected Croatian red and white wines on the growth of human normal and tumour cells in vitro. Effects on growth of cervical carcinoma (HeLa), colon carcinoma (Caco-2, HT-29), poorly differentiated cells from lymph node metastasis of colon carcinoma (SW-620), larynx carcinoma cells (HEp-2) and normal fibroblasts (WI38) were tested by MTT-assay. Radioactive substrate incorporation tests were used for assessing effects on DNA, RNAs and proteins syntheses. Concentration of polyphenols in wines was assessed according to the method of Singleton and Rossi. Ethanol in the wine concentrates was determined by MS-GC method. Results of the cytotoxicity test showed that colon carcinoma cells (Caco-2, HT-29), as well as colon carcinoma metastasis (SW620) were the most affected by dealcoholized red wines in concentrations 25% and 12.5% v/v. Amount of total phenols in the red wines was significantly higher (5-10 times) compared to the white wines. The red wine with the greatest polyphenol content was shown to be the most effective. Red wine samples in concentration 25% v/v statistically significantly inhibited the growth of all tested cell lines, including fibroblasts. Tested white wines showed no or negligible growth inhibitory effect against tumour and normal cells. Tumour cells, HeLa and Hep-2, treated by red wine V3 (12.5% v/v) and Hep-2 cells treated by red wine V4 (12.5% v/v) exhibited slightly growth-stimulatory effects. Biosynthesis assay of DNA, RNA and proteins indicated a standstill in the growth of treated cells. Our results indicate that polyphenol-rich domestic wine might have potential pro-therapeutic effect on transformed colonic cells.

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Pollack Periodica
Authors: Kalman Buzas, Peter Budai, and Adrienne Clement

One and a half year long field sampling was established in order to evaluate the contamination of storm water runoff. The event means (EMC) total petroleum hydrocarbons (TPH) concentration of the runoff was a function of the actual traffic intensity and the rainfall depth. It was concluded that this TPH, of which dominant component is the engine-oil (characteristically C28) does not form an ‘oil-in-water’ type emulsion in the condition of normal motorway-operation, but is interlocked to asphalt, rubber and soot particles of maximum some ten microns size. This condition influences the possibility, way and extent of separation alike. The separation equipments and their sizing applied so far are not suitable to achieve efficient surface water protection. Practical prevention method of accidental type environment pollution was also suggested. On the basis of the international literature evaluation, technical solutions capable to decrease the runoff pollution were summarized. Among these, useful calculation method was developed for designers to determine the sufficient storage capacity (water quality volume) of reservoirs applied for water quality protection. Monitoring technique of runoffs, which are characterized time dependent, variable pollutant concentrations by their nature, was proposed. It was stated that the administrative regulation should aim at the EMC instead of current concentration. Beside TPH information was gained on polycyclic aromatic hydrocarbons (PAHs), suspended solids, heavy metals, pH, and nutrient (N, P) pollution of the runoff, which are valuable for the grounding of further research results.

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Juniperus phoenicea L. (Cupressaceae) is an evergreen small tree or shrub, distributed throughout the Mediterranean area from Portugal to Israel and North Africa. J. phoenicea has been used for centuries in traditional medicine and its berries are widely used in flavours, perfumes, and to aromatize alcoholic beverages.The aim of the present work was to evaluate the chemical composition and antifungal activity of essential oils of Juniperus phoenicea berries from Jordan.The essential oils of the berries were isolated by hydrodistillation and analysed by GC and GC-MS. Minimal inhibitory concentration (MIC) and minimal lethal concentration (MLC) were used to evaluate the antifungal activity of the essential oils against dermatophytes, yeasts and Aspergillus species.The essential oils were characterized by high percentage of α-pinene (75.5 and 84.2%), which distinguish them from oils from other countries where α-pinene is usually present in lower percentages. Essential oils exhibited high antifungal activity against dermatophytes and Cryptococcus neoformans with MIC values ranging from 0.32–2.5 μl ml−1.These results support that essential oils from J. phoenicea berries may be useful in the treatment of dermatophytosis. Further studies should be stimulated in order to evaluate toxicity and optimal concentrations for clinical applications.

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Acta Alimentaria
Authors: K. Szentmihályi, M. Szilágyi, J. Balla, L. Ujhelyi, and A. Blázovics

Magnesium participates in numerous enzymatic reactions in the human body and it has essential role in the maintenance of the antioxidant system. Since several magnesium compounds have been applied in the food and pharmaceutical industry, our purpose was to investigate the antioxidant/free radical scavenging activity of some magnesium compounds in vitro. The antioxidant/prooxidant effect of inorganic salts (e.g. MgCl2) and organic complexes (e.g. Mg-gluconate) was determined with chemiluminometric method (H2O2/•OH-microperoxidase-luminol) and heme mediated LDL oxidation (LDL-heme-H2O2 ) in vitro. It has been stated that the chemiluminescence method and LDL (low density lipoprotein) oxidation measurement is applicable in the presence of magnesium salts and complexes. Most of the compounds do not generate free radicals and the antioxidant/prooxidant effect depends on the quality of the ligand and the concentration. In the concentration range used, some representatives of the magnesium compounds (MgO, Mg-gluconate, Mg-polygalacturonate) investigated showed radical generating activity measured with chemiluminescence method, whereas the LDL oxidation has not been affected. Magnesium citrate and malate proved to be antioxidants measured with the chemiluminescence method and they slightly accelerate the LDL oxidation in the system and in the concentration applied. In vitro some of the ligands of magnesium compounds showed antioxidant activities.

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The oral administration of hyaluronic acid has been shown to improve skin health. This study aimed at utilizing ultrasound treatment to enhance the production of hyaluronic acid by lactobacilli. Among the 16 strains of lactobacilli screened, a higher production of hyaluronic acid (P<0.05) was observed from seven strains namely, Lactobacillus casei BT 2113, Lactobacillus casei BT 1268, Lactobacillus casei BT 8633, Lactobacillus casei FTDC 8033, Lactobacillus acidophilus FTDC 1231, Lactobacillus gasseri FTDC 8131 and Lactobacillus rhamnosus FTDC 8313. Upon ultrasonic treatment, hyaluronic acid concentration increased significantly (P<0.05) in all the seven strains studied. The use of ultrasonication at 100% amplitude increased the hyaluronic acid content (P<0.05) up to 51.6 % with concentrations ranging from 0.262 mg ml−1 to 0.385 mg ml−1, while an amplitude of 20% yielded a lower increase ranging from 0.227 mg ml−1 to 0.310 mg ml−1. Increasing duration of ultrasonic treatment (from 1 min to 3 min) also significantly (P<0.05) improved the concentration of hyaluronic acid in some strains. Our data demonstrated that a sub-lethal physical treatment, such as ultrasonication, can be applied to increase the membrane permeability of lactobacilli cells and subsequently increase the release of bioactive metabolites.

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The microbiological spoilage of foods depends on the initial microbiological contamination and some factors which influence the growth of microorganisms. Therefore, reducing the initial cell count is necessary for both extending shelf-life and improving food safety. Physical, chemical and combined treatments serve this purpose. In these experiments, the effect of trisodium phosphate dipping (0-15% solutions) was studied. Chicken wings were used, which after dipping (1 min) in the solution were packed in PE-PA-PE pouches and stored at 4 °C. Aerobic mesophilic (Nutrient Agar, Merck), pseudomonad (Pseudomonas Selective Agar, Oxoid), and Enterobacteriaceae counts (VRBD Agar, Merck) were determined by Spiral Plate Technique at 30 °C incubation temperature. Effect of 3.8, 5.7, 7.6% trisodium phosphate dipping solutions was studied as a function of storage time. Immediately after treatment, total colony count was reduced by maximum 1.5 log cycles. Pseudomonads were the most sensitive. One day after treatment with these low concentration solutions, the colony count was reduced by 2 log cycles. Na3PO4concentration higherthan 7.6% practically did not result in higher effectivity. The growth rate and maximum cell count of surviving fraction were estimated as a function of trisodium phosphate concentration. It can be concluded from fitted survival curves that immediately after treatment the initial viable cell count was reduced and the critical spoilage level (107g-1) has been reached 2-3 days later than in case of the untreated samples, i.e. the shelf-life was extended.

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