Food Samples Of Animal Origin Research Articles

Poly[(2-(acryloyloxy) ethyl]trimethylammonium chloride-co-ethylene dimethacrylate monolith on-line solid-phase extraction coupled with liquid chromatography and tandem mass spectrometry for the fast determination of salicylic acid in foodstuffs.

We report the fabrication of an anion-exchange monolithic column in a stainless-steel chromatographic column (10mm×2.1mm i.d.) using [2-(acryloyloxy) ethyl]trimethylammonium chloride as the monomer and ethylene dimethacrylate as the crosslinker. The prepared monolith was developed as the adsorbent for the on-line solid-phase extraction of salicylic acid in various animal-origin foodstuffs combined with liquid chromatography and tandem mass spectrometry. The monolith was characterized by using Fourier transform infrared spectroscopy, scanning electron microscopy, nitrogen adsorption analysis, and elemental analysis. Potential factors affecting the on-line solid-phase extraction and liquid chromatography with tandem mass spectrometry analysis were studied in detail. Under the optimized conditions, the total analysis time including cleanup and liquid chromatography with tandem mass spectrometry separation was 17min. The developed method gave the linear range of 15-750μg/kg, detection limits (S/N=3) of 5μg/kg, and quantification limits (S/N=10) of 15μg/kg. The recoveries obtained by spiking 10, 20, and 100μg/kg of salicylic acid in the animal-origin food samples were in the range of 85.2-98.4%. In addition, the monolith was stable enough for 550 extraction cycles with the precision of peak area ≤11.6%.

Diversity of CTX-M-1-producing E. coli from German food samples and genetic diversity of the blaCTX-M-1 region on IncI1 ST3 plasmids

Antimicrobial resistance to cephalosporins is commonly mediated by extended-spectrum β-lactamases (ESBL) or plasmidic AmpC β-lactamases (pAmpC). In livestock blaCTX-M-1 is the most frequently detected ESBL-encoding gene. As transmission to consumers through contaminated food is often proposed, this study characterized ESBL/pAmpC-producing E. coli collected from food samples. Therefore, samples from food products of animal origin and vegetables were screened for phenotypically resistant E. coli by selective cultivation. The ESBL genotype was confirmed for 404 isolates with the majority of them (n = 212) harboring the blaCTX-M-1 gene. PFGE and MLST analyses as well as plasmid characterization were carried out for 89 isolates, selected under epidemiological aspects. In addition, 44 isolates were investigated by whole genome sequencing and/or sequencing of their plasmids on an Illumina Miseq platform.MLST and PFGE indicated a diverse population of CTX-M-1-producing E. coli in German food samples with no spread of single clonal lineages. The majority of the isolates harbored the blaCTX-M-1 gene on IncI1 plasmids. Frequently, the gene was associated with the ISEcp1 element and located on a ∼100 kb IncI1 plasmid depicting the plasmid multilocus sequence type (ST) 3. The blaCTX-M-1 gene and its flanking sequences were located within the shufflon of the type IV pilus region in diverse orientations.In conclusion, dissemination of the CTX-M-1 β-lactamase within food samples of animal origin is driven by the transmission of a ∼100 kb large IncI1 ST3 plasmid. Apart from conjugal transfer of IncI1 ST3 plasmids the transmission of the blaCTX-M-1 gene might be further promoted through mobilization due to its location within a recombination hot-spot of IncI1 plasmids.

Application of affinity microspheres for effective SPE cleanup before the determination of sulfamerazine by HPLC

This paper describes the application of poly (ethylene glycol dimethacrylate-N-methacryloyl-L-tryptophane methyl ester) [p(EGDMA-MATrp)] microspheres as an affinity sorbent for the SPE (solid phase extraction) cleanup of sulfamerazine (SMR) from food samples of animal origin before high performance liquid chromatography (HPLC) analysis. The microspheres were prepared by suspension polymerization of ethylene glycol dimethacrylate (EGDMA) and N-methacryloyl-L-tryptophane methyl ester (MATrp) as a crosslinker and a monomer, respectively. Various parameters affecting the SPE cleanup efficiency of the p(EGDMA-MATrp) microspheres (contact time, pH, initial SMR concentration, ionic strength etc.) were optimized. Under the optimized conditions, maximum adsorption capacity was found to be 8.55 ± 0.44 mg/g sorbent at pH 5.0. 90% of the adsorbed SMR was desorbed by using ACN:MeOH (5:5) mixture as a desorption agent. Applicability of the microspheres for the SPE cleanup of SMR residues in the food samples such as egg and milk with HPLC was also determined. It was demonstrated that the prepared p(EGDMA-MATrp) microspheres could be repeatedly applied for SPE cleanup of sulfamerazine before chromatographic analysis. Also, the recoveries of SMR in milk and egg samples were reasonably satisfactory and in the range of 71 to 90%.

Residue of insecticides in foodstuff and dietary exposure assessment of Brazilian citizens

The goal of this work is to study the presence of 17 different pyrethroids and chlorpyrifos in animal origin food samples, including chicken, beef, fish, eggs and milk. The samples were analyzed by GC/NCI-MS/MS in order to determine their insecticide concentration levels, the relation between the amount of insecticides and the lipid content, as well as their isomeric composition. Bifenthrin, cypermethrin, cyhalothrin, permethrin, deltamethrin and chlorpyrifos have been detected in real samples. The highest levels find were verified for chlorpyrifos (45.7 μg L−1, 17.5 μg kg−1 ww) and cypermethrin (2.75 μg L−1, 14.7 μg kg−1 ww) in milk and beef, respectively. The estimate of daily intake showed that none of these insecticides exceeded the safety limits of the acceptable daily intake values. A strong correlation between the amount of pesticides and lipid content was found for beef, fish and chicken samples. Regarding the isomers, a predominance of cis isomers in samples contaminated with cypermethrin was verified.

Indiscriminate use of pesticides and lack of sanitary control in the domestic market in PeruUso indiscriminado de pesticidas e falta de controle sanitário do mercado interno no Peru

RESUMENNotificar el nivel de contaminación de los alimentos de origen animal y vegetal monitorizados por la autoridad sanitaria en Perú, que realiza el Servicio Nacional de Sanidad Agraria (SENASA), para poder informar al consumidor y a las autoridades nacionales de la situación del control sanitario del mercado interno en el país.La información se ha obtenido de los informes incluidos en la página web del SENASA. Los datos considerados corresponden a los de los informes de evaluación de todos los tipos de alimentos de origen vegetal y animal analizados en el período comprendido entre 2011 y 2015.Para este período, los resultados muestran que 202 muestras de animales y vegetales incumplen las normas (son no conformes). El porcentaje de muestras de alimentos de origen animal no conformes fue 12,68% y el correspondiente a alimentos de origen vegetal, 24,87%. En el periodo estudiado, se observó un aumento de 30,73% de las muestras no conformes, que incluso ha alcanzado 50%.Los niveles de contaminación de los alimentos de origen animal y vegetal monitorizados por el SENASA son preocupantes. Por ello, se recomienda iniciar acciones concretas para afrontar esta situación, confiando en que estas acciones sean priorizadas y planificadas con la participación de todos los actores del sistema agrícola de Perú a fin de introducir los cambios regulatorios necesarios y establecer indicadores claros, medibles y alcanzables de monitorización y control para proteger la salud de la población.

Monitoring of dioxins and related toxic compounds in food of animal origin in Greece

Polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) and "dioxin-like" polychlorinated biphenyls (PCBs) are environmental pollutants belonging to the persistent organic pollutants (POPs). PCDDs and PCDFs have never been produced intentionally, but they are formed by incomplete combustion of organic material in the presence of chlorine, during industrial processes or intentional and unintentional burning of solid waste. PCBs have been produced industrially as mixtures and have been used in various applications, though their production has been banned since the 1970's. Their toxicity is mediated through the interaction with the aryl hydrocarbon (AH) receptor, causing severe health effects to humans after chronic exposure, which include developmental and immunological effects, carcinogenicity and chloracne. More than 90% of the daily human intake is due to food ingestion and especially, to the consumption of fat-containing animal food products, due to the lipophilic nature of these compounds. In order to control food contamination by these compounds, the European Union has set maximum limits for PCDD/Fs and PCBs in food products (EU Regulation 1881/2006/EC). The Mass Spectrometry and Dioxin Analysis Laboratory of "NCSR" Demokritos has been operating since 2002 and it performs analysis of PCDD/Fs and PCBs in food, feed, biological and environmental samples, applying international protocols of analysis (EPA 1613, EPA 1668), based on appropriate sample clean-up and determination by high resolution mass spectrometry (HRMS), using the isotope dilution method, as specified by the EU Regulation 1883/2006/EC. The Laboratory has been accredited according to ISO/IEC 17025 by ESYD and it is the National Reference Laboratory of the European Commission for Greece and Cyprus. Here we present here a comprehensive report of the activities of the Mass Spectrometry and Dioxin Analysis Laboratory during its operation, concerning the monitoring of dioxins and similar toxic compounds in food of animal origin in Greece. Through collaboration with the official bureaus of food, environment and health control organizations of Greece, the Laboratory has conducted analysis in a large number of food and animal feed products sampled randomly in the Greek market. The results are well below the EU maximum levels and, in general, lower than those monitored in other European and Mediterranean countries. This has been attributed to the fact that Greece is not highly industrialized and has never produced PCBs and does not perform systematic waste incineration. On the other hand, samples have been collected and analysed from areas suspected for dioxin contamination, such as areas affected by accidental fires, landfills or exposed to industrial pollution. In some of these cases, unusually high levels of dioxin contamination in food samples of animal origin have been observed, in some cases above EU limits, and appropriate measures have been taken by Greek authorities to prevent their consumption and to restore normal dioxin levels.

Matrix-effect free multi-residue analysis of veterinary drugs in food samples of animal origin by nanoflow liquid chromatography high resolution mass spectrometry

In this work, a sensitive method based on nanoflow liquid chromatography high-resolution mass spectrometry has been developed for the multiresidue determination of veterinary drugs residues in honey, veal muscle, egg and milk. Salting-out supported liquid extraction was employed as sample treatment for milk, veal muscle and egg, while a modified QuEChERS procedure was used in honey. The enhancement of sensitivity provided by the nanoflow LC system also allowed the implementation of high dilution factors as high as 100:1. For all matrices tested, matrix effects were negligible starting from a dilution factor of 100, enabling, thus, the use of external standard calibration instead of matrix-matched calibration of each sample, and the subsequent increase of laboratory throughput. At spiked levels as low as 0.1 or 1 µg kg−1 before the 1:100 dilution, the obtained signals were still significantly higher than the instrumental limit of quantitation (S/N 10).

Prevalence of Enterotoxin Genes and Antibacterial Susceptibility Pattern of Staphylococcus aureus Strains Isolated from Animal Originated Foods in West of Iran.

The aims of our study were to evaluate the prevalence of Staphylococcus aureus (S. aureus) strains in food samples of animal origin, examine their antibacterial susceptibility pattern, and to detect staphylococcal enterotoxin (SEs) genes and the mecA gene in isolated S. aureus strains using the polymerase chain reaction (PCR). . A total of 1050 food samples including 671 raw milk and dairy products and 379 raw meats were collected between September 2013 and June 2014 in Hamadan, Iran. Food samples were analyzed for S. aureus identification. The antibiotic susceptibility pattern of all isolates was determined using the disk agar diffusion method followed by detecting mecA resistance gene using PCR. In addition, harboring of SE genes were determined using a multiplex PCR assay targeting nine genes. . A total of 98 (9.3%) S. aureus strains were isolated from 1050 food samples. Of the 98 isolates examined, the most frequent resistance was observed to erythromycin (30.6%), followed by tetracycline (29.6%), gentamicin (27.6%), clindamycin (26.5%), ciprofloxacin and rifampin (24.5%), trimethoprim-sulfamethoxazole (14.3%), and cefoxitin (5.1%). All cefoxitin resistant isolates were positive for mecA. The prevalence of SEs was 77.6% (n=76). Among the genes that code classic enterotoxins, sea was the most frequent and was carried by 25.5% of isolates, followed by see in 18.4%, sed in 11.2%, sec in 5.1%, and seb in 4.1% of isolates. Among the detected enterotoxins, seg was the predominantly identified enterotoxin gene in isolates with prevalence of 35.7%. The seh gene with prevalence of 1% and sei gene with 3.1% were other detected enterotoxins with low frequencies. . The high prevalence of SE genes detected indicates a potential risk for causing animal-originated food poisoning. The increasing prevalence of community-acquired MRSA and its emerging antibiotic resistance in foods is a serious problem for public health.

Isolation, identification, and characterization of Listeria spp. from various animal origin foods.

Aim:The present study was undertaken with the prime objective of isolating and identifying Listeria spp. from various foods of animal origin sold at retail market outlets in the city of Navsari, Gujarat.Materials and Methods:Total 200 samples comprising of milk, milk products, meat, and fish (50 each) collected aseptically from local market which were subjected first to pre-enrichment in half strength Fraser broth followed by enrichment in full strength Fraser broth and subsequent plating on PALCAM agar. The growth with the typical colony characteristics were further identified up to species level on the basis of their morphological and biochemical characteristics. Cultures identified as Listeria monocytogenes were further subjected to in vitro pathogenicity tests and detection of different virulence-associated genes viz. actA, hlyA, and iap using polymerase chain reaction.Results:Of the total 200 food samples of animal origin; 18 (9%) were found positive for Listeria spp. which were identified as Listeria seeligeri (6, 33.3%), Listeria innocua (5, 27.7%), Listeria welshimeri (4, 22.2%), and L. monocytogenes (3, 16.6%). The highest prevalence was observed in milk samples (8). Species wise, 6 isolates of L. seeligeri which included two each from cow milk, buffalo milk, and meat samples; 5 L. innocua isolates included four recovered from fish and one from meat sample; 4 L. welshimeri comprised of two isolates from ice cream and one each from buffalo milk and meat sample; and 3 isolates of L. monocytogenes recovered from milk (1 cow and 2 buffalo milk). All 3 L. monocytogenes isolates screened for the presence of virulence genes viz. actA, hlyA, and iap using the specific primers revealed the presence of all the genes suggesting the possibility of danger of foodborne listeriosis among raw milk consumers.Conclusion:Listeria spp. was isolated from 9% (18/200) of the animal origin food samples viz.; milk, milk products, meat, and fish with the highest prevalence in the milk samples. L. monocytogenes was isolated from 3 milk samples only. L. seeligeri was the predominant species isolated followed by L. innocua, L. welshimeri, and L. monocytogenes in this study. L. monocytogenes were found to carry virulence genes like actA, hly A, and iap genes suggesting the pathogenic potential of these isolates.

Phenotypic and genotypic studies on Escherichia coli strains isolated from food products of animal origin

Foodstuffs of animal origin may present hazards, due to bacterial contamination. This study was conducted to determine Escherichia coli in some types of animal source foods (raw milk, raw beef meat and raw poultry meat). Bacteriological examination of total 246 raw food samples of animal origin, raw milk, (105); beef meat (31) and poultry meat (110) were collected from different localities in Ismailia City showed that 64/246 (26.01%) of samples were infected with E. coli. Serological identification of (10) E. colistrains revealed that they were belonged to O111 polyvalent 1; O44 polyvalent 2 (2 strains for each); O78 polyvalent 4; O146 polyvalent 2; O26 polyvalent 1; O119 polyvalent 1; O86 polyvalent 1 and O18 polyvalent 3 (1 strain for each). E. coli strains showed high susceptible rate to Ciprofloxacin (CIP), (100%) and high resistance (100%) to Ampicillin (AMP), Metronidazole (MTZ), Amoxicillin (AML), and Vancomycin (VAS). Four strains of the isolated E. coli were submitted to molecular studies for detection of the eaeA (protein intimin), iutA (encoding aerobactin) and iss (increased serum survival protein) genes, by using PCR technique.

Identification and molecular characterization of pathogenic bacteria in foods confiscated from non-EU flights passengers at one Spanish airport

Two hundred food samples of animal origin confiscated from passengers arriving on flights from non-European countries at the International Airport of Bilbao (Spain) were tested for the presence of four main bacterial foodborne pathogens (Campylobacter spp., Escherichia coli O157:H7, Listeria monocytogenes and Salmonella spp.) during 2012 and 2013. Overall, 20 samples were positive for L. monocytogenes (10%) and 11 for Salmonella spp. (5.5%), whereas Campylobacter spp. and E. coli O157:H7 were not detected in any sample. The positive isolates were widely clustered: 14 and 7 different pulsotypes for L. monocytogenes and Salmonella spp. isolates, respectively. Nine sequence types (ST) were detected for L. monocytogenes: ST2 (45%), ST9 (15% isolates), ST8 and ST87 (10%), and ST308, ST37, ST155 and ST378 (5%). The Salmonella spp. isolates belonged to seven serovars: monophasic serovar 4,12:d:− (3; 27.3%), Rauform (2; 18.2%), Anatum (2; 18.2%), Oranienburg, Enteritidis, Newport and Typhimurium (1; 9.1% each). Antibiotic resistance among L. monocytogenes isolates was high, especially for clindamycin and daptomycin (more than 95% of the isolates). These results indicate that food samples imported by travelers in their personal luggage may harbor the most prevalent L. monocytogenes genotypes and Salmonella spp. serovars responsible for foodborne outbreaks worldwide. Consequently, international travel can play an important role in the prevalence and dissemination of successful clones of foodborne pathogenic bacteria, and continuous monitoring of international movements is of importance to better understand clonal evolution and emergence and dissemination of successful lineages.

Multi–antibiotic resistant bacteria in frozen food (ready to cook food) of animal origin sold in Dhaka, Bangladesh

To investigate the bacterial load and antibiotic resistance pattern of bacterial isolates obtained from (ready to cook) frozen food samples of animal origin in Dhaka, Bangladesh. A total of 20 samples of frozen ready to cook food of animal origin were purchased from different separate grocery stores in Dhaka, Bangladesh. Bacteria were isolated and identified based on the basis of biochemical properties. A total of 57 isolates has been isolated from 20 samples, of them 35.08% were Gram positive and 64.92% were Gram negative organisms. Highest percentages of isolated organisms were Staphylococcocus spp. (24.56%), Alcaligene spp. (17.54%), Klebshiella spp. (12.28%) and the lowest percentages of organisms were Enterococcus spp., Actinobacillus spp. and Proteus spp. Antibiogram results clearly showed that levofloxacin and imipenem were the most effective drug against the isolates. The less effective antibiotics were chloramphenicol and nalidixic acid and resistance was highest against ciprofloxacin. The most contaminated food was chicken nuggets. This type of frozen food contaminated with multi-antibiotic resistant microorganisms can be potential vehicles for transmitting food-borne diseases.

Escherichia Coli Phylo-Groups Drug Resistance Pattern

Copyright © 2014, Alborz University of Medical Sciences. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. The paper entitled “Antibiotic Resistance Pattern of Escherichia coli Groups A, B1, B2 and D Isolated from Frozen Foods and Children with Diarrhea in Sanandaj, Iran” published in International Journal of Enteric Pathogens. 2013.1(1), is a short, simple article that discusses original research conducted on E. coli strains isolated from 125 samples of frozen food from animal sources, and 466 rectal swabs from children with diarrhea. Certainly, such periodic surveys conducted on various samples that may have a major role in the spread of pathogenic bacteria would shed light on the susceptibility of pathogens and help in the containment of spread of infections in hospital environments as well as in the community. In recent years, the spread and acquisition of antibiotic resistance genes between different species of disease causing bacteria has been on the rise. Among these E. coli strains of E. coli have gained world wide attention and their pattern of antibiotic resistance has been a subject of controversy among specialists of the field. The existence of four distinct sub-species within E. coli has been established; these are designated A, B1, B2 and D (1) that can be divided into seven subgroups (A, A1, B1, B22, B23, D1 and D2), according to the combination of the three genetic markers chuA, yjaA and DNA fragment TspE4.C2 (2). Thus, this study would have been better if they had determined the other three subgroups. Therefore, phylo-group determination can reveal a great deal regarding sub-group membership. Based on the available databases, it has been found that E. coli extrapathogenic phylo–group strains are globally disseminated and drug resistant with a broad range of human hosts (3, 4). Further studies are needed to characterize their origins, virulence mode of actions, geographical distribution, clinical associations and modes of dissemination. The findings of the study conducted on frozen food samples of animal origin and rectal swabs from children with diarrhea in the city of Sanandaj by Kalantar et al. are interesting and can be helpful as a reference for future studies for comparative purposes.

Detection of Escherichia coli O157:H7 using immunomagnetic separation and mPCR in Turkish foods of animal origin

The present study was conducted to investigate the presence of Escherichia coli O157:H7 in food samples of animal origin and to detect its virulence genes by immunomagnetic separation technique and multiplex PCR (mPCR). A total of 500 samples (consisting of diced meat, minced meat, burger, raw cow's milk and raw cow's milk cheese) were analysed. Escherichia coli O157:H7 was detected in 5 (1%) of 500 analysed samples including two diced meat, one minced meat and two raw-milk cheese. None of the burger samples tested contained E.coli O157:H7. Three isolates obtained from minced and diced meat were found to carry stx1 , stx2 , hlyA and eaeA genes whereas two isolates from raw-milk cheese were found to harbour the stx1 , eaeA and hlyA genes. The results of this study suggest that raw meat and raw-milk cheese tested could pose public health problems in consumers with regard to their virulence factors. Escherichia coli (E.coli) O157:H7 is an important human pathogen. Escherichia coli 0157:H7 infections have been associated with consumption of uncooked meat and meat products, as well as unpasteurized dairy products. This study demonstrated that without specific tests for E.coli virulence factors raw meat and raw-milk cheese could pose public health problems to Turkish consumers.

Characterization of ShigatoxigenicEscherichia coliStrains from Burkina Faso

Shigatoxigenic Escherichia coli (STEC) cause serious foodborne infections that lead to diarrheal disease and sequelae worldwide. In Burkina Faso, West Africa, STEC strains from environmental and human sources have not been isolated and characterized before. In this study, 21 STEC strains were isolated from food samples of animal origin and human feces using colony hybridization of the Shiga toxin gene stx. The STEC strains belonged to 15 different serotypes, including O43:H2, O8:H(-), and O2:H2. All strains were positive for stx(1) and 10 also for stx(2). The most common stx(1) subtype was stx(1a), and the most common stx(2) subtype was stx(2b). In five strains, stx(2) subtypes stx(2a) and/or stx(2c), which were previously associated with hemolytic uremic syndrome, were present. Some of the strains possessed the gene saa, encoding autoagglutinating adhesin. None of the strains possessed the gene eae, encoding intimin. Two STEC strains carried also an enterotoxigenic E. coli-associated gene estIa, encoding heat-stable enterotoxin. The STEC isolated from food in Burkina Faso are potentially pathogenic for humans based on the virulence gene combinations that they possess and phenotypes that they express.

English

  One of the major public health challenges nowadays is the rapid emergence of antibiotic resistant pathogens. This study investigated the antibiotic resistance pattern in bacterial isolates obtained from frozen food samples of animal origin in Sanandaj and Ahvaz Iran. A total of 250 packages of food of animal origin were purchased from different separate grocery stores in Sanandaj and Ahvaz during one year. Bacteria were isolated and identified based on national procedures. Antibiogram was done according CLSI guideline. From a total of 250 samples collected from Sanandaj and Ahvaz, 68 (54.4%) and 71 (56.8%) were positive for bacteria respectively. In Sanandaj Prevalence of Escherichia coli, Citrobacter Spp, Enterobacter Spp, Staphylococcocus Spp, and Bacillus cereus was 40, 18, 05, 03 and 2% respectively. The most contaminated food was chicken nuggets (80%). Antibiogram results clearly showed that resistance to Tetracycline and Ampicillin was 55 and 50% respectively. Similarly, in Ahvaz also prevalence of E. coli, SalmonellaSpp, and Proteus Spp, were 52, 03.2 and 02.4% respectively. The above bacteria were 39 and 26% resistance to Ampicillin and Tetracycline respectively. The frozen food samples are perhaps the potential vehicles for transmitting food-borne diseases. Antimicrobial resistance among enteric organisms in food animals was generally low; however, the significance of this study lies in the detection overall resistance of bacterial isolates from the frozen food samples of animal origin in Ahvaz and Sanandaj against different antibiotics.   Key words: Frozen food, antimicrobial resistance, Escherichia coli.

Simultaneous Detection of Residues of 25 β2-Agonists and 23 β-Blockers in Animal Foods by High-Performance Liquid Chromatography Coupled with Linear Ion Trap Mass Spectrometry

A sensitive method has been developed for the simultaneous determination of residues of 25 β₂-agonists and 23 β-blockers in animal foods by high-performance liquid chromatography coupled with linear ion trap mass spectrometry (HPLC-LIT-MS). This method is based on a new procedure of hydrolysis and extraction by 5% trichloracetic acid, and then cleaned up by mixed strong cation exchange (MCX) cartridges coupled with a novelty cleanup step by methanol. Methanol and 0.1% formic acid were used as mobile phases for gradient elution, while a Supelco Ascentis Express Rp-Amide column was used for LC separation. ESI positive ion scan mode was used with consecutive reaction monitoring (CRM, MS³). Nine β₂-agonists labeled by the deuterium isotope were used as internal standards for quantification. The linear ranges of 48 analytes were from 5 to 200 μg/L; the coefficient of correlation was not less than 0.995. Blank pork muscle, blank liver, and blank kidney were selected as representative matrix for spiked standard recovery test. The recoveries of each compound were in the range of 46.6-118.9%, and the relative standard deviations were in the range of 1.9-28.2%. Decision limits (CCα, α = 0.01) of 48 analytes in muscles, liver, and kidney samples ranged from 0.05 to 0.49 μg/kg, and the detection capability (CCβ, β = 0.05) ranged from 0.13 to 1.64 μg/kg. This method was successfully applied to 110 real animal origin food samples including meat, liver, and kidney of pig and chicken samples.

Simultaneous determination of fluoroquinolones in foods of animal origin by a high performance liquid chromatography and a liquid chromatography tandem mass spectrometry with accelerated solvent extraction

A confirmatory and quantitative method based on a high performance liquid chromatography UV detector (HPLC-UV) and a liquid chromatography tandem mass spectrometry (LC–MS/MS) with an extraction procedure of accelerated solvent extraction (ASE) has been developed for simultaneous determination of 15 kinds of fluoroquinolones in various animal origin food samples. The sample preparation procedures consist of an extraction step with acetonitrile and a cleaning-up step with Oasis HLB cartridge. Parameters for extraction pressure and temperature, cycle of ASE, clean-up, and analysis procedure have been optimized systematically. The recoveries of FQNs spiked in the tissues as the muscle, liver, kidney of swine, bovine, chicken and fish at a concentration range of 10–800μg/kg were found between 70.6% and 111.1% with relative standard deviations (RSD) less than 15% in HPLC. The LOD and LOQ of the HPLC for the 15 FQNs were 3μg/kg and 10μg/kg, respectively, and those of the LC–MS/MS were 0.3 and 1μg/kg, respectively. These rapid and reliable methods can be used to efficiently separate, characterize and quantify the residues of 15 FQNs (Marbofloxacin, Enoxacin, Fleroxacin, Ofloxacin, Pefloxacin, Lomefloxacin, Danofloxacin, Enrofloxacin, Orbifloxacin, Cinoxacin, Gatifloxacin, Sarafloxacin, Difloxacin, Nalidixic Acid, Flumequine) in food of animal origin.

Dietary intake of hexabromocyclododecane diastereoisomers (α-, β-, and γ-HBCD) in the Belgian adult population

A study was performed to assess exposure of the Belgian population to HBCD diastereoisomers. Measurements of HBCD were performed by UPLC-MS/MS, on 45 composite samples from 5 major food groups: dairy (products), meat (products), eggs, fish (products) and a group of “other” products. The medium bound estimated average daily intake (EDI) of ΣHBCD in the Belgian population was 0.99 ng kg −1 bw d −1. The diastereoisomer contribution to the mean EDI showed a predominance of γ-HBCD at 67%, followed by α-HBCD at 25% and 8% for β-HBCD. These results are consistent with the pattern found in the two food groups contributing the most to the EDI: meat (products) and the group of “other” products. Anyway, it has to be noted that diastereomeric distribution of HBCD can change due to bioisomerisation in biological material. Levels of HBCD diastereoisomers found in Belgian food samples of animal origin were low in comparison with those found in other EU countries and the resulting EDI was substantially below the proposed thresholds.

Antimicrobial Resistance Profile ofStaphylococcus aureusIsolated from Clinical Samples and Foods of Animal Origin

Staphylococcus aureus has been well established as a clinical and epidemiological pathogen and can cause infections at many anatomical sites. Increasing insusceptibility to β-lactams and the glycopeptides complicates the treatment of these infections. We isolated 584 strains of S. aureus from various clinical and animal origin food samples during (from January 2006 to December 2007) the survey. Resistance to 15 antibiotics frequently used in human medicine and veterinary practice was also determined. A remarkable level of penicillin resistance was detected in both clinical (98.3%) and food (92.0%) S. aureus isolates. But, there were no S. aureus strains that were resistant to vancomycin, teicoplanin, linezolid, and quinupristin/dalfobristin. The rate of resistance to tetracycline, ciprofloxacin, levofloxacin, methicillin, gentamicin, tobramycin, norfloxacin, and moxifloxacin among the human and foods S. aureus isolates ranged from 50.3% to 56.3% and 1.4% to 9.5%, respectively. In our survey, in vitro susceptibility data suggested that the incidence of resistance among the S. aureus strains isolated from food were not remarkably high, excluding penicillin. Although the transfer of antibiotic resistance of S. aureus from foods to humans probably occurs less frequently than is generally assumed, the increasing prevalence of resistance in the strains of human origin may have important therapeutic implications.