Entity

Time filter

Source Type


Tkacikova S.,State veterinary and Food Institute | Kozarova I.,University of Veterinary Medicine in Kosice | Mate D.,University of Veterinary Medicine in Kosice
Food Additives and Contaminants - Part A Chemistry, Analysis, Control, Exposure and Risk Assessment | Year: 2010

Maduramycin is a polyether ionophoric coccidiostat used to prevent coccidiosis in poultry at a prescribed concentration over a certain time interval. Due to public health concerns about the presence of coccidiostat residues in poultry, the aim of the present study was to determine the level of maduramycin residues in the tissues of broiler chickens fed commercially produced feed containing 5mg kg-1 of maduramycin in complete feed throughout the 5-day withdrawal period (WP). The residues were investigated by liquid chromatography (LC) coupled with electrospray ionisation (ESI) tandem mass spectrometry (MS/MS). The limit of detection (LOD) and limit of quantification (LOQ) of the method were 0.3 and 0.8μgkg -1, respectively. The average recovery based on matrix-fortified calibrations for chicken tissues was 90%. Maduramycin was found to be rapidly distributed in all tissues. The highest concentrations of maduramycin residues were found in the heart followed by the skin, liver, gizzard, kidneys and, finally, muscle (thigh and breast). On day 5 of the WP, residue concentrations of maduramycin did not decline below the LOQ of the method. Our results emphasize the need to establish a maximum residue limit (MRL) for maduramycin to control its residue levels in edible tissues from chickens before slaughter. © 2010 Taylor and Francis.


Rosinska D.,State veterinary and Food Institute | Lehotay J.,University of Tirana
Journal of Liquid Chromatography and Related Technologies | Year: 2014

The main biogenic amines in foods are histamine, tryptamin, cadaverin, putrescin, spermin, and spermidin. The samples of pork, beef, and poultry were extracted with 0.6 mol · l-1 perchloric acid and extract was filtered. Histamine, cadaverine, putrescine, and tyramine were determined by reverse-phase HPLC using a C18 stationary phase column. Acetate buffer with water (pH 4.5) and acetate buffer with acetonitrile (45/55 v/v) was used as a mobile phase, the flow-rate was 1 mL · min-1. The post column derivatization technique with OPT buffer (phthaldialdehyde buffer) as derivatization agent and the fluorescence detector at 330 nm and 465 nm as excitation and emission wavelengths was used. Limit of detection for biogenic amines was 0.2 mg · kg-1 and limit of quantification was 0.5 mg · kg-1. The method was useful over a wide concentration range of biogenic amines. The concentrations from 0.5 to 1 000 mg · kg-1 of histamine, tyramine, putrescine, and cadaverine in pork, beef, and poultry could be detected easily without any noticed disadvantage. Concentrations of biogenic amines were determined in pork, beef, and poultry and concentrations were increased depending on temperature and time. Concentrations of cadaverine and putrescine were highest for ground meat stored at 24°C after 10 days. Highest influence of temperature on production of biogenic amines was found in poultry samples. The concentrations of tyramine, putrescine and histamine were higher than 100 mg · kg-1 and the concentration of cadaverine was more than 400 mg · kg-1. Copyright © 2014 Taylor & Francis Group, LLC.


Kozarova I.,University of Veterinary Medicine in Kosice | Macanga J.,University of Veterinary Medicine in Kosice | Goldova M.,University of Veterinary Medicine in Kosice | Major P.,University of Veterinary Medicine in Kosice | Tkacikova S.,State veterinary and Food Institute
Food Additives and Contaminants - Part A Chemistry, Analysis, Control, Exposure and Risk Assessment | Year: 2011

Maduramycin is a coccidiostat authorized as a feed additive in poultry. Council Directive 96/23/EC stipulates that monitoring of foods of animal origin for residues of coccidiostats is mandatory. The aim of the present study was to evaluate the STAR for the screening of maduramycin residues in the tissues of broiler chickens and pheasants. Both animal species were supplied feed medicated with Cygro l% premix according to recommendations for use (5 mgkg-1 of complete feed). The residues were investigated for a period of 7 days: day 0 (the last day of the administration of maduramycin), days 1-5 (the days of the withdrawal period) and day 6 (the first day after elapse of the withdrawal period). According to STAR the positivity of the sample (the presence of residues of antibacterial substances) is indicated by a zone of inhibition exceeding 2 or 4mm in width, depending on the test organism. Maduramycin residues were detected only on the plates seeded with the test organism Bacillus stearothermophilus var. calidolactis ATCC 10149. The results showed that there was higher potential for the presence of maduramycin residues in broiler chickens than in pheasants. All chicken tissues (muscle/thigh and breast/gizzard, liver, heart, kidneys, spleen, lungs) were positive for maduramycin (inhibition zones ≥4 mm) not only throughout the withdrawal period, but also even 5 days after elapse of the withdrawal period. In the case of pheasants the positive results were detected in the gizzard, liver, heart, kidneys, spleen and lungs. On day 5 of the withdrawal period no positive results were detected; however, on day 6 the heart and spleen were positive again. © 2011 Taylor & Francis.


Pagacikova D.,State veterinary and Food Institute | Lehotay J.,University of Trnava
Journal of Liquid Chromatography and Related Technologies | Year: 2015

Synthetic colors are a substance, liquid or powder, which are added to foods to replace natural color lost during processing. A rapid and simple method for simultaneous determination of seven synthetic colors such as amaranth (E123), ponceau 4 R (E124), sunset yellow (E110), allura red AC (E129), red 2 G (E128), carmoisine (E122), and erythrosine (E127) in meat products using the technique of high-performance liquid chromatography (HPLC) with photodiode array detector is described. The sample is extracted with mixture of methanol and ammonia (80:20 v/v) in ultrasonic bath, and then the extract is filtered through a glass filter paper. Synthetic colors were determined by reversed-phase liquid chromatography using a C18 column and a photodiode array detector. Synthetic colors were separated using HPLC/diode-array detector method on 250 × 4 mm I.D LichroSphere RP-18endcapped column (Merck, Darmstadt, Germany) with 5 μ C18 stationary phase, and the chromatograms were detected at 500 nm. Acetate buffer (pH 4.8) and acetate buffer (pH 4.8) with acetonitrile (40/60 v/v) were used as the mobile phase, and the flow rate was 1.0 mL min-1. Satisfactory recoveries, ranging from 77.0% (erythrosine) to 99.5% (sunset yellow), were obtained. The method was useful over a wide concentration range of synthetic colors. Synthetic colors as low as <0.1 mg kg-1 and as high as >500 mg kg-1 in various meat products could be detected easily without any noticeable disadvantage. The limit of detection and the limit of quantification of individual synthetic dyes were 0.05 mg kg-1 and 0.1 mg kg-1, respectively. © 2015 Copyright Taylor & Francis Group, LLC.


Vierikova M.,State veterinary and Food Institute | Hrnciarikova E.,State veterinary and Food Institute | Lehotay J.,University of Trnava
Journal of Liquid Chromatography and Related Technologies | Year: 2013

Natamycin is a fungistatic antibiotic that is used therapeutically only for a surface treatment and does not cause resistance of yeasts and fungi. It has a broad spectrum of activity for most yeasts and fungi that come into consideration in food. A methods based on the use of ultra-peormance liquid chromatography tandem mass spectrometry (UPLC/MS/MS) and time of flight mass spectrometry (UPLC=TOF MS) interfaced with electrospray were devised for determination of natamycin content in cheese samples. Sample preparation included extraction of fat and protein removal by congelation. In case of low concentrations of natamycin, extract was concentrated by SPE. UPLC was performed on an Acquity UPLC BEH C18 (100mm×2.1 mm). UPLC=TOF data were acquired in TOF MS full scan mode. UPLC=MS=MS data acquisition was achieved using multiple reaction monitoring (MRM). The elaborated methods for determination of natamycin in cheese were validated. Detection limits vary depending on the mass spectrometer. For UPLC= TOF detection limit is 50 μg · kg -1, for the the triple quadrupole 5 μg · kg-1. The relative standard deviation (RSD) of the method was for the UPLC/TOF, 3%, and for UPLC/MS/MS, 5.5%. The described methods meet all the criteria of Decision 2002/657/EC and are easy to use in routine analyses. Copyright © 2013 Taylor & Francis Group.

Discover hidden collaborations