Abstract:To develop a screening and confirmation method of UPLC-LTQ Orbitrap MS for 48chemical medicine including fluoroquinolone, sulfanilamide, tetracycline, malachite green, nitrofuran, olaquindox and carbadox mixed into traditional Chinese herbal medicine for fishery.MethodsThe samples were extracted by ethyl acetate, cleaned by C₁₈ sorbent, separated by reversed phase chromatography(Velocity:250μl/min, Cylinder temperature:30℃, Sample size:10μl), and gradient eluted with methanol/water (containing 0.1% formic acid). Final detection was performed by LTQ Orbitrap MS in full scanning mode. The TOXID software combined with database retrieval was used for screening and confirmation of 48veterinary drugs. ResultsThe limits of detection (LODs) and the limits of quantification (LOQs) of 48veterinary drugs were 0.0060-0.21mg/kg and 0.020-0.72mg/kg, respectively. The method showed good linearity over the linear range, r²=0.9796-0.9997. The recoveries were 81.9%-114.4%, 84.0%-114.3%, 80.9%-114.8% for the three spiked levels at 0.25,0.50and 1.0mg/kg, respectively. The RSDs were in the range of 1.56%-14.3%.ConclusionThe method was rapid, accurate, reliable and precise. It was suitable for the screening and confirmation of chemical medicine adulterated into traditional Chinese herbal medicine.

Abstract:To establish an accurate, rapid and specific fluorescent PCR method to detect pathogenic gene of Vibrio parahaemolyticus(VP).Methods7VP standard stains were used to verify 6literary methods of fluorescent PCR and the new method establish in this study. The specificity was verified using 6common foodborne pathogenic bacteria. ResultsThe newly-established method could detect all 3kinds of hemolysins simultaneously, and the results were consistent with those of stains tracing and standard PCR methods. There was no cross reaction with common foodborne pathogens.ConclusionThe fluorescent PCR system could detect pathogenic gene of VP with better accuracy, reliability, speed and specificity, which was more applicable.

Abstract:Anoval method of nano-immunomagnetic separation (Nano-IMS) plus loop-mediated isothermal amplification (LAMP) was established for the rapid detection of Vibrio parahemolyticus.MethodsThe Nano-Immunomagnetic Beads (Nano-IMB) were created by using the monoclonal antibody of V. parahemolyticus and named Nano-IMB-Vp, which was highly specific to V. parahemolyticus. The method of Nano-IMS-LAMP was established for the rapid detection of V. parahemolyticus from seefoods. ResultsThe capture ratio of Nano-IMB-Vp was reached 74% at the level of 103cfu/ml. In pure culture, the sensitivity of Nano-IMS-LAMP was reached 140cfu/ml culture medium. The specific of this LAMP method was tested by using 134targets and 74non-targets bacteria. The results showed that the LAMP method was highly specific to V. parahemolyticus. Nocross-reaction was founded. The detection limit of Nano-IMS-LAMP reached 2cfu/25g in artficial samples when the period of time for enrichment was shorted to 8h.ConclusionThe method of Nano-IMS-LAMP could shorten the period of time for enrichment effectively, which can apply to the rapid detection of V. parahemolyticus.

Abstract:To establish an indirect ELISA method of β-lactamase detection in milk.MethodsThe Elisa method of Ampicillin was set up and optimized with ampicillin-HRP conjugate and Ampicillin antibody. The method was used to detect the ampicillin in samples and negative control, and β-lactamase was determined indirectly by comparing OD₄₅₀ values. ResultsThe indirect ELISA method for β-lactamase was established, and the sensitivity was 0.0005IU/ml.ConclusionThis method was accurate and reliable, and could be widely applied to detect β-lactamase in milk.

Abstract:To study the major allergens of edible mantis shrimp among residents of Tianjin.MethodsSerums of 116patients of edible mantis shrimp allergy were collected by skin prick test, and the main allergens were identified from the crude shrimp extract by immunoblotting technique with serums as the probe. Five typical serums were chosen form 62positive samples. The cross-reactivity between edible mantis shrimp and scallop allergens were tested by immunoblotting inhibition experiments. ResultsThe western blot showed that the serum of allergy pateints had different binding sites. The reaction rate of 35kDa tropomyosin was 64.5% (40/62), and that of 67kDa and >90kDa were 41.9% (26/62) and 54.8% (34/62) respectively. Immunoblotting inhibition showed that the main cross-reaction protein was tropomyosin. The larger molecular weight protein showed less cross-reactivity.ConclusionIn addition to tropomyosin, several large molecular weight proteins of edible mantis shrimp could cause allergy among adults in Tianjin and cross-reactivity with scallop was low. This suggested that some of the high-molecular-weight proteins might play an important role in edible mantis shrimp allergy.

Abstract:To obtain an overview of epidemic characteristics of Staphylococcal enterotoxins(SEs), Panton-Valentine leukociclin(PVL), exfoliative toxins(ETs), and toxic shock syndrome toxin1(TSST-1) genes of Staphylococcus aureus(S.aureus) isolated from food and food poisoning samples in Xi’an from 2006to 2011, and to compare the difference of gene distribution and genotyping between the two kinds of isolates.MethodsThe genes of sea, seb, sec, sed, eta, etb, tsst-1and pvl were detected by multiplex PCR. The multiplex PCR assay combined the primers of sea, seb, sec and sed in one reaction and the other four primers in another. ResultsOut of 40S.aureus strains isolated from food, 17strains were detected toxin genes(42.50%). In 21strains isolated from food poisoning, 18strains were detected toxin genes(85.71%). The detection rate of toxin genes in food poisoning isolates was much higher than that in food isolates (P<0.01). Sea(25%) and eta(12.5%) were the most common genes and sea(10.00%) and sea+eta(7.50%) were the main toxin genotypes in food isolates, and etb, tsst-1genes were not detected. Sea(76.19%) and sec(28.57%) were the most common genes and sea(42.86%) and sea+sec+tsst-1(14.29%) were the main toxin genomic types in food poisoning isolates, and PVL gene were not detected.ConclusionThere were significant differences in toxin gene distribution and genotyping between S.aureus isolates from food and isolates from food poisoning.

Abstract:ObjectiveTo investigate antibiotic decomposition of raw milk β-lactamase residues in milk samples of commercially availability in Nantong, and to provide the basis for reasonably controlling β-lactamase added in milk. MethodsTo test β-lactamase in milk samples employing "sulbactam sensitive β-lactamases drug test method-cup method, in milk and milk products" published by Ministry of Health. ResultsAmong 102milk samples from 5manufactures, β-lactamase was detected in 15samples (relevance ratio:14.7%) from 2factories. The differences between bacteriostatic ring of 15positive samples were among 3.9-17.9mm. Conclusionβ-lactamase adding residues are available in commercial milk products in the market of Nantong, and some residues are tremendous, which would make food safety hazards to some extent. So it''s necessary to enhance administration and control.\=

Abstract:To screen and identify the genetic strains of genetically modified (GM) papayas in Shenzhen market for the sake of food safety risk assessment, and in order to provide scientific base for government regulation.Methods57Papayas were randomly collected from Shenzhen markets, detected by Real-time polymerase chain reaction (PCR) with CaMV35S promoter and NOS terminator for screening. The GM positive samples were identified with strain-specific primers and probes. ResultsIn 57papaya samples, the GM positive rate was 91.2% including 96.1% GMYK16-0-1strain and 3.9% Huanong-1strain respectively. Other strains were not detected. There was significant difference in the positive rates of transgenic papaya between supermarket and terminal market origin. No sample was labeled GM relevant.ConclusionNearly 90% GM papayas were the line that had not been approved by Chinese Ministry of Agriculture. Therefore the administrative departments should reinforce the supervision of GM papaya.

Abstract:A method for the determination of ethoxyquin residue in food by liquid chromatography with fluorescence detector was developed.MethodsThe homogenized sample was extracted with n-hexane under alkaline conditions, then cleaned by liquid-liquid extraction (LLE) with n-hexane after adjusting the pH value. The targeted compound was determined by liquid chromatography-fluorescence detector. The chromatographic separation were achieved in Agilent Eclipse XDB-C18(150mm×4.6mm, 5μm) with a gradient elution using methanol-water as mobile phase at a flow rate of 1.0ml/min, the column temperature was 30℃, and the injection volume was 20μl. The ethoxyquin was detected under FD at λ_ex/λ_em=365nm/425nm.Results The linear range of ethoxyquin was 0.05-10mg/L, and the correlation coefficient was 0.9992. The limit of detection was 7.5μg/kg (S/N=3) and the limit of quantification was 25μg/kg (S/N=10). In different food matrixes, the average recoveries of ethoxyquin under three spiked levels were 80.5%-95.9%, with RSDs (n=8) of 3.1%-11.5%.Conclusion This method was practical, maneuverable and suitable for the determination of ethoxyquin residue in various food.

Abstract:To develop a method for the determination of three kinds of synthetic colorants in meat products by solid phase extraction (SPE)-high performance liquid chromatography (HPLC).Methods After extraction using ammonia-90% ethanol (1/99, V/V) solution, the extract of meat products was purified on PLS SPE coloumn. The eluent was analyzed by HPLC with photo-diode array detector (PDA). The HPLC separation was performed on a Dikma Spursil C18(4.6mm×150mm,5μm) column and gradient eluted with acetonitrile-0.05mol/L ammonium acetate solution,the flow rate was 1.0ml/min, the injection volume was 10μl ,the detection wavelength were 200-700nm, the column temperature was 30℃.Results The linear concentration range of Amaranth, Carmine and Allura Red was 0.5-25.0μg/ml, and the correlation coefficients were 0.9996,0.9997and 0.9993, respectively. The average recovery of spiked sample was in the range of 94.2%-99.1%.Conclusion The method was sensitive and accurate with a good reproducibility and suitable for determination of synthetic colorants in meat products.

Abstract:To develop an analytical method for determination of fipronil and chlorfenapyr residues in foodstuffs by gas chromatography-tandem mass spectrometry (GC-MS/MS).MethodsFipronil and chlorfenapyr were extracted with acetonitrile and cleaned-up by a PSA solid phase extract (SPE) column for GC-MS/MS determination. Fipronil and chlorfenapyr were separated by a THERMO TR-Pesticide II column and detected by multiple reaction monitoring (MRM) with electrospray ionization operating in the positive ion mode.Results The calibration curves were linear between the range of 5-50μg/L with r≥0.998. The recoveries of fipronil spiked sample ranged 78.2%-102.5% with RSD 6.8%-15.2%, and the recoveries of chlorfenapyr ranged 77.0%-104.1% with RSD 6.9%-17.1%. The limits of detection (LODs) and limits of quantification (LOQs) of fipronil and chlorfenapyr were both 5and 10μg/kg, respectively.Conclusion GC-MS/MS in positive ion mode is an simple, rapid, accurate analytical method for determination of fipronil and chlorfenapyr residues in foodstuffs

Abstract:To establish a method for simultaneous determination of 15PAHs in plant oil by high performance liquid chromatography with fluorescence detection.Methods The sample was dissolved in n-hexaneand, and cleaned up with neutral alumina SPE cartridges．The separation of 15PAHs was carried out by waters-PAHs column (4.6mm×250mm, 5μm) with a gradient elution using acetonitrile-water as mobile phase at a flow rate of 1.5ml/min, the column temperature was 30℃, and the injection volume was 10μl. Detection was carried out by a fluorescence detector with external standard. Results The limit of detection (LOD) was in the range of 0.15～2.0μg/kg with average recovery ranging from 78.0% to 115.2%. The relative standard deviation was in the range of 0.2%～2.0%.Conclusion The method had the advantages of simple pretreatment, high sensitivity and reproducibility, which could be applied to the determination of the 15PAHs in plant oil.

Abstract:To establish a method for the determination of chlorpromazine in pork by gas chromatography-mass spectrometry.Methods The sample was homogenized and extracted by ethyl acetate, degreased by hexane and acetonitrile, purified by solid phase extraction, and eluted by 5% ammoniated methanol. Ion fragments of 86,3, 272and 318were selected for qualitative and quantitative analysis by gas chromatography-mass spectrometry.Results Good linearities were shown in 0.051-0.25μg/ml with the relative coefficients of 0.9992. The limit of detection was 2.0μg/kg. The average recoverys were from 87.1% to 97.3% and the relative standard derivation was 3.15%.Conclusion It could be applied to determine the chlorpromazine in pork.

Abstract:ObjectiveA quantitative detection method for Campylobacter jejuni was developed to provide accurate data for food safety risk assessment. MethodsBased on the principle of Most Probable Number (MPN) and ISO/TS 10272-3and GB/T 4789.9-2008, fresh chickens and chicken faeces with spiked sample were cultivated in different enrichment cultures, cultivation environment and methods, the optimization was verified by standard recovery test. Results10cfu/g Campylobacter jejuni as spiked samples, 12.26and 10.96MPN/g were detected in Preston broth of fresh chickens and chicken faeces, while 2.38and 2.32MPN/g were detected in Bolton broth which had significant difference (P＜0.05). The spiked sample was detected as 12.26and 12.12MPN/g, 12.26and 10.96MPN/g, 12.26and 12.86MPN/g, and 10.82and 12.12MPN/g with three gases-incubator, gas-producing bags, gas extract-exchange, and candle-cylinder, respectively. No significant difference was found between the three-gas incubator method and the other three (P＞0.05). The spiked samples were detected as 15.8and 15.2MPN/g in static culture, 11.4and 8.7MPN/g in shaking culture, and there was significant difference between them (P＜0.05). The recoveries were 115.25%, 111.5% and 95.0% with different spiked concentrations. ConclusionThe method could be applied to detect the Campylobacter jejuni specifically, quantitatively and accurately in seriously contaminated samples. \=

Abstract:Implying the theories of public policy and public management, using multiple methods including literature review,comparative thinking,empirical data,and inductive logic, basing on the recent researches and first hand data accumulation from practice,the paper clearly depicts the current status and problems of food safety regulation, discusses the related key issues,and draws the lessons from other countries. As policy recommendation,the paper proposes a permanent solution to improve capacity of food safety regulation in the new era.On the occasion of the major reformation of national food safety regulation system,these suggestions and comments are significant for food safety regulation in the long term.

Abstract:To understand the condition of Salmonella contamination in broilers through the production chain of hatching, breeding, slaughtering, processing and distribution, determine the vulnerable point and sample category, and to provide a scientific basis for the prevention and control of food-borne diseases caused by Salmonella. MethodsSixteen monitoring points including broiler hatcheries, farms, slaughterhouses and markets were set up to collect samples with random sampling method. The Salmonella were detected based on the handbook of National Surveillance on Food-borne Pathogenic Bacteria of 2012.Results In 2012,4samples of 17kinds were detected. 202strains of Salmonella were isolated from 13kinds of samples with an overall detection rate of 16.78%. The salmonella were classified into 4groups and 28serum types with 1exception. Indiana serotype were most prevalent and accounted for 37.13%. The detection rate was the highest in slaughtering process, the second quarter of the year, and broilers after deplumation, with detection rate 23.14%, 21.74% and 42.19%, respectively.ConclusionThe cross-contamination of Salmonella was serious in broilers industry in Jinan. The supervision and monitoring should be strengthened through the whole process. In order to reduce the level of Salmonella cross-contamination, the critical control points should be determined and corresponding operating procedures should be formulated.

Abstract:ObjectiveTo investigate the salmonella contamination during processing in broiler slaughterhouse.MethodsSamples included anal swabs of chickens, deplumed chicken carcasses, precooled chicken carcasses, frozen chicken carcasses, water in precooling pool, cutting knives, chopping boards and smearing samples of workers’ hands. The samples were tested for Salmonella according to Food-borne Pathogen Monitoring Manual. ResultsA total of 293Salmonella strains were detected in 896samples during 2011-2012, and the positive rate was 32.7%. The positive rate of Salmonella in chicken carcasses was higher than that in living chickens. The dominant serotypes were S.indiana and S.enteritidis in 2012, and S.indiana,S.typhimurium and S.enteritidis in 2011. The proportion of S.indiana decreased, but other advantageous serotypes such as S.typhimurium and S.enteritidis increased in the chicken samples after slaughter. ConclusionSalmonella existed in the whole processing link in slaughterhouse, and the contamination was aggravated during the slaughter process.\=

Abstract:To study the bacteria contamination in frozen intestines.Methods Sixty-five strains of bacteria isolated from frozen intestines, which collected in Nantong casings manufacturing and processing enterprises between 2010and 2012, were identified by 16S rDNA PCR amplification and sequence analysis.Results It showed that 20specices of bacteria blonging to 13genuses were identified,and the main bacterial species were Proteus mirabils, Enterococcus hirae and Enterococcus faecalis.In addition, some of them may cause disease in humans and animals under certain conditions.Conclusion A variety of bacteria may be carried by frozen intestines, the relevant supervision and study should be further strengthened.

Abstract:The aim of the study was to investigate the hygiene and sanitation of seafood enterprises according to Enterococcus in processing water.MethodsAccording to the method of ISO7899-2∶2000(Water quality-Detection and enumeration of Enterococcus-Part 2:Membrane filtration method), Enterococcus was isolated and identified. Primers and probes were designed and synthesized targeting tuf gene.Results The results showed that 14.6% of the 41isolates were Enterococcus positive. Most of them were GroupⅡ strains. Conclusion We should take effective measures of prevention and control because the health status was not satisfying.

Abstract:ObjectiveTo know the Enterobacter sakazakii contamination in homemade infant formula powder which provides scientific basis for consumers. Methods32bags of Infant formula powder bought from supermarket and the retail market were checked according to the 2011and 2012editions of the national foodborne pathogen monitoring manual. Results2strains of Enterobacter sakazakii were found from 32samples, the detection rate was 6.25%. Among them, The detection rate of Enterobacter sakazakii from Infant formula powder was 4.35%(1/23); and The detection rate of Enterobacter sakazakii from Infant cereal food formula was 11.11%(1/9). ConclusionEnterobacter sakazakii contamination exists in infant formula which sales form Liujiang County. Food security can not be ignored, monitor of infant food should be strengthen, which can prevent and control the food poisoning incident caused by Enterobacter sakazakii.\=

Abstract:To investigate the conditions of pesticide residues in vegetables in Mianyang, and provide inspection basis for assuring the safety of vegetables.Methods The method of GB/T5009-2003was applied to determine the contents of pesticide in randomly collected samples, and the results were evaluated according to GB2763-2005. Results A total of 155vegetable samples were detected in 2010and 2011, the detection rates were 71.00% and 80.00%, the violation rates were 31.00% and 40.00%. The violation rates of edible fungi, legume, root, leaf and fruit vegetables were 27.03%, 22.86%, 28.00%, 70.97% and 22.22%, respectively. The highest violation rate was in Triazophos, following by Carbonfuran, Methamidophos and Propoxur.Conclusion In Mianyang city, pesticide residues were relatively serious in vegetables especially the leaf vegetables. In order to assuring the safety of vegetable intake, effective measures should be taken. The inspection and administration should be strengthened, and the usage of high toxic pesticides should be prevented from the source, and the monitoring on vegetables through planting and sale chain should be strengthened.

Abstract:To investigate the reason of a food poisoning case, and the origins of the suspicious factors of this case.MethodsFind out the suspicious meal according to the epidemiological curve. Then evaluate the foods in the suspicious meal through case-control study, and analyze the correlations between different foods and different dozes. Foods and case samples were collected for laboratory testing.Results 61cases were founded and the major symptoms were abdominal pains (98%), diarrhea(90%), nauseous(54%) and so on. Eating plain chicken was the risk factor (OR=9.25,95%CI∶1.14-200.07), and showed a dose-effect relation (χ^2test for trends:25.71,P<0.01). The main reason for cross contamination was that the chef processed the plain chicken and Tilapia at the same time. Vibrio parahaemolyticus was detected in the anus swab samples from patients, the result of PFGE showed 100% homology.ConclusionThe food poisoning was caused by plain chicken contaminated by Vibrio parahemolyticus. It is necessary to strengthen the supervision and administration of catering distribution, and improve health consciousness of the public to prevent such case.

Abstract:Fusarium toxins, the metabolites of trichothecenes, zearalenone and fumonisins, are widespread in cereals and their products which can cause toxic effects through oral chronic exposure to human and animals. Fusarium toxins also have specific toxic effects, such as metabolism disorders, liver toxicity, kidney toxicity, neurotoxicity, skin phototoxicity, hematopoietic toxicity and so on. Mycotoxins have been shown to have mutagenic and carcinogenic effects and some fusarium toxins can cause reproductive and developmental toxicities to human and animals. This paper reviews the reproductive and developmental toxicity of fusarium toxins on human and animal.

Abstract:Phytosterols is a kind of steroidal compoundwith perhydrocyclopentanophenanthrene as the main structure. Phytosterols are natural components of oil seeds, legumes, and grains. It has been reported that phytosterols could prevent and cure prostate glanddisease and act as immune system modulators,and they also have antiinflammation and anticancer properties.Presently, dietary application of phytosterols and phytosterolesters keeps increasing in many food types.In this paper, the application and safety issue of novel food phytosterols is discussed.