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Emerging mycotoxins, such as enniatins and beauvericin, are common contaminants in vegetal matrices, but recently, the occurrence of mycotoxins in foodstuffs from animal origin has been also reported as they can be present in edible tissues of animals fed with contaminated feedstuffs. Sea bass, sea bream, Atlantic salmon and rainbow trout from aquaculture analyzed in the present survey showed contamination by emerging Fusarium mycotoxins enniatins (ENs). ENs were extracted from raw and cooked fish with acetonitrile and analyzed by Liquid Chromatography coupled to Mass Spectrometry. In this study, the stability of ENs was evaluated during food processing by the application of different cooking methods (broiling, boiling, microwaving and baking treatments). All treated samples showed a reduction in mycotoxin levels with different percentages depending on the type of EN and the fish species. Thus, the reduction obtained ranged from 30 to 100%. The thermal treatments have shown to be a good strategy to mitigate ENs content in edible fish tissues. On the other hand, some ENs degradation products originated during the application of thermal treatments were identified. [ABSTRACT FROM AUTHOR]

High performance liquid chromatography-mass spectrometry was used for the determination of 15 mycotoxins in water and fish plasma samples, including aflatoxins, fumonisins, ochratoxin A, sterigmatocistin, fusarenon-X and emerging Fusarium mycotoxins. In this work, dispersive liquid–liquid microextraction (DLLME) was assessed as a sample treatment for the simultaneous extraction of mycotoxins. Results showed differences in recovery assays when different extraction solvents were employed. Ethyl acetate showed better recoveries for the major part of mycotoxins analyzed, except for aflatoxins B 2 , G 1 and G 2 , which showed better recoveries when employing chloroform as extractant solvent. Fumonisins and beauvericin exhibited low recoveries in both water and plasma. This method was validated according to guidelines established by European Commission and has shown to be suitable to be applied in dietary and/or toxicokinetic studies in fish where is necessary to check mycotoxin contents in rearing water and fish plasma. [ABSTRACT FROM AUTHOR]

Abstract: A new rapid, sensitive, reproducible and reliable method was developed for the quantitative determination of enniatins A, A1, B and B1, beauvericin and fusaproliferin in dry and fresh pasta by liquid chromatography-triple quadrupole-tandem mass spectrometry. A comparative study of different rapid and economical extraction procedures was performed for the extraction of these mycotoxins in pasta. For this purpose, three different approaches were studied during the extraction step (Ultra-Turrax, ultrasonic bath and microwave). Optimal extraction conditions were reached using Ultra-Turrax with acetonitrile for 3 min without purification step. The chromatographic separation of the six mycotoxins was accomplished in 15 min. The method was extensively validated with satisfactory results: recovery rates ranged from 86 to 112% and the relative standard deviations were lower than 15%. Limits of detection ranged from 0.02 to 0.15 μg kg−1. The applicability of the method was assessed with the analysis of 30 samples of dry and fresh pasta. [Copyright &y& Elsevier]

Abstract: One of the main sources of emerging Fusarium mycotoxins in human nutrition is the cereals and cereal products. In this study, an analytical method to determine enniatins A, A1, B and B1 (ENs), beauvericin (BEA) and fusaproliferin (FUS) based on Ultra-Turrax extraction followed by liquid chromatography coupled to triple quadrupole mass spectrometer detector (MS/MS QqQ), was applied for the analysis of pasta. For this purpose, 114 commercial samples of pasta were acquired from supermarkets located in Valencia. The results showed higher frequencies of contamination in organic pasta than in conventional pasta, while the concentration levels were variable for both types of pasta. In positive samples, BEA levels varied from 0.10 to 20.96μg/kg and FUS levels varied from 0.05 to 8.02μg/kg. ENs levels ranged from 0.25 to 979.56μg/kg, though the majority of the values were below 25μg/kg. Besides, it was observed the simultaneous presence of two or more mycotoxins in a high percentage of the samples. Finally, an evaluation of the dietary exposure of the emerging Fusarium mycotoxins was performed in the Spanish population. The prevalence of ENs, BEA and FUS in cereal products suggests that the toxins may pose a health risk to Spanish population. [Copyright &y& Elsevier]

An approach based on solid-phase microextraction-liquid chromatography-mass spectrometry (SPME-LC-MS) has been developed for determining 12 insecticides (bromophos ethyl, chlorpyrifos methyl, chlorpyrifos ethyl, diazinon, fenoxycarb, fonofos, phenthoate, phosalone, pirimiphos methyl, profenofos, pyrazophos, and temephos) in honey. The influence of several parameters on the efficiency of the SPME was systematically investigated. Under optimal conditions, the procedure provided excellent linearity (>0.990), detection and quantification limits (between 0.001 and 0.1 µg g-1 and between 0.005 and 0.5 µg g-1, respectively), and precision (<19% at the quantification limits and from 6 to 14% at ten times higher concentrations). However, recoveries were not so good, ranging from 19 to 92%. Honey samples were found that were contaminated with bromophos ethyl, diazinon, fonofos, pirimiphos ethyl, pyrazophos, and temephos at estimated concentrations from 6.2 ± 1.2 to 19 ± 3 ng g-1. [ABSTRACT FROM AUTHOR]

Abstract: One hundred and sixteen orange and tangerine samples from an agricultural cooperative of the Valencian Community (Spain) were analyzed for bitertanol, carbendazim, hexythiazox, imazalil, imidacloprid, methidathion, methiocarb, pyriproxyfen, thiabendazole, and trichlorfon by liquid chromatography–mass spectrometry (LC–MS) after a conventional multiresidue extraction procedure. Of 52 samples that contained pesticide residues, carbendazim was detected in 27 (51.9%) in the concentration range of 0.02–0.04mgkg−1, hexythiazox in 22 (42.3%) in the concentration range of 0.02–0.05mgkg−1, imazalil in 8 (15.0%) in the concentration range of 0.02–1.2mgkg−1, imidacloprid in 5 (9.6%) in a concentration range of 0.02–0.07mgkg−1 methidathion in 17 (32.6%) in the concentration range of 0.06–1.3mgkg−1, and methiocarb in 1 (2%) at a concentration of 0.02mgkg−1. Bitertanol, pyriproxyfen, thiabendazole and trichlorfon were not detected in any sample. Although 19 samples contained residues of two or three of the studied pesticides, no sample exceeded the European Maximum Residue Limits (MRLs). The results show that despite a high occurrence of pesticide residues in oranges and tangerines from Valencian Community, the contamination levels of these residues could not be considered a serious public health problem according to European Union (EU) regulations. [Copyright &y& Elsevier]

A quantitative matrix solid-phase dispersion and liquid chromatography–atmospheric pressure chemical ionization mass spectrometry (LC–APCI–MS) method is outlined for the simultaneous analysis of dithiocarbamates (DTCs) and their degradation products in plants. Compounds analyzed are dazomet, disulfiram, thiram and the metabolites ethylenthiourea and propylenthiourea. The performance of two different sample preparation protocols, the proposed one and other based on solid-phase extraction, as well as, of both atmospheric pressure ionization sources, APCI and electrospray, were compared. The effect of several parameters on the extraction, separation and detection was studied. Dithiocarbamates and metabolites were dispersed with carbograph, eluted with a mixture of dichloromethane–methanol, and then, identified by monitoring the base peak of the spectra corresponding to [M+H]+. The method was validated for avocados, cherries, lemons, nuts, oat, oranges, peaches, rice and tomatoes. Average recoveries varied from 33 to 109%, and relative standard deviation were between 4 and 21% with limits of quantification ranged from 0.25 to 2.5 mg kg−1, except for thiram and disulfiram, which were not recovered from fruits with high acid content. The procedure was applied to the determination of DTCs and their metabolites in fruits, vegetables and cereals taken from different markets of Valencia, Spain. [Copyright &y& Elsevier]

A liquid chromatographic–mass spectrometric method has been developed for the determination of bitertanol, carbendazim, fenthion, flusilazole, hexythiazox, imidacloprid, methidathion, methiocarb, pyriproxyfen and trichlorfon. Two procedures, based on stir bar sorptive extraction (SBSE) and matrix solid-phase dispersion (MSPD), have been evaluated for the extraction of these compounds in oranges. Their respective advantages and disadvantages are also discussed. The recoveries obtained by MSPD ranged from 47 to 96% and the relative standard deviations (RSDs) ranged from 1 to 15%, whereas with the SBSE method the recoveries were between 8 and 84% and the RSDs between 4 and 16%. Although, the limits of quantitation of most compounds are much better (0.001–0.05 mg kg−1) by SBSE, it is not suitable to determine some polar pesticides as carbendazim, imidacloprid and trichlorfon. Results obtained by both methods were compared, in terms of sensitivity and selectivity, with a classical ethyl acetate extraction method, and the three methods were applied to analyze real samples. As MSPD is easier to perform, faster than the organic solvent extraction, and shows equal accuracy and resolution, its application for analyzing pesticides in oranges is recommended. [Copyright &y& Elsevier]

The article discusses the evaluation of polar pesticides in rice fields by High-Pressure Liquid Chromatography (HPLC) with Ultra Violet detector. According to the study, the carbamate pesticides have become very popular because of their wide spectrum of biological activity, and its widespread use can lead to water pollution. The study has showed that the limits of detection, calculated using HPLC-grade water, were under the European Union limit for drinking waters for carbaryl, carbofuran, dietofencarb and iprodione.

Highlights: [•] Study of the effects of time, temperature and pH on the enniatins stability. [•] Determination of enniatins degradation products by LC–MS-LIT. [•] High percentages of reduction were obtained after thermal treatments. [•] An effect of pH in the enniatins stability was not demonstrated. [•] Degradation products were formed during thermal treatments. [Copyright &y& Elsevier]

Abstract: Forty-five samples of Spanish follow-up infant formula with different chemical compositions were analyzed determining the emerging Fusarium mycotoxins beauvericin (BEA), enniatins (ENs) (A, A1, B, B1), and fusaproliferin (FUS). The samples were extracted three times with ethyl acetate using an Ultra-turrax homogenizer. Mycotoxins were identified and quantified using a liquid chromatography (LC) coupled to a diode array detector (DAD). Results showed that the percentage of the samples contaminated with ENs and FUS were 46.6 and 20.0% respectively, whereas all analyzed samples were free of BEA. The ENs A and B were detected only in one sample with 149.6 and 39.4 mg/kg respectively. The ENB1 was the more detected mycotoxin with levels ranging from 11.4 to 41.9 mg/kg. The ENA1 was detected at levels ranging from 6.3 to 101.7 mg/kg. The minor Fusarium mycotoxin FUS was detected in a range variable from 0.7 to 1.7 mg/kg. Finally, dietary exposure of Spanish infants (between 6 and 12 months) to ENs, BEA and FUS, was estimated through the consumption of commercial follow-up infant formula by the calculation of the estimated daily intake (EDI). Considering the sum of the mycotoxins studied, the data evidenced that the EDI was 236.2 μg/kg bw/day. [Copyright &y& Elsevier]

Abstract: Biogenic amines on fish tissue are formed as a result of bacterial contamination and spoilage during storage. A new method based on liquid chromatography (LC) and tandem mass spectrometry (MS/MS) using a triple quadrupole (QqQ) analyser was developed for the analysis of eight biogenic amines (cadaverine, histamine, phenylethylamine, putrescine, spermine, spermidine, tyramine and tryptamine) in fish tissues. Sample preparation was performed by extraction with trichloroacetic acid 5% and solid phase extraction clean up with STRATA X cartridge. The MS/MS method was validated and compared with a method based on the analysis of dansyl derivatives by LC and fluorescence detector (FD). MS/MS achieved higher sensitivity (from 0.02mgkg−1 for spermidine and phenylethylamine to 0.2mgkg−1 for spermine) when compared to FD (from 1mgkg−1 for putrescine and tyramine to 4mgkg−1 for histamine); MS/MS method showed higher precision too, with intraday relative standard deviations (RSDs) from 1% to 4% with respect to those obtained with FD method (from 3% to 17%). Recovery study was conducted at two different fortification levels and the average ranged from 71% to 93% for all of the studied compounds with RSDs lower than 18%. Matrix-matched standards were used to counteract matrix effect observed in MS/MS determination. The applicability of the method was demonstrated by the analysis of biogenic amines in fish obtained from commercials of Valencia. [Copyright &y& Elsevier]

Abstract: Sixty-eight samples of cereals products, including breakfast cereals (n =48) and infant cereals (n =20), purchased from supermarkets and pharmacies in Rabat-Salé area from Morocco were analysed for the determination of six emerging mycotoxins: four enniatins ENs (ENA, ENA1, ENB and ENB1), beauvericin (BEA) and fusaproliferin (FUS). Samples were extracted with a mixture of acetonitrile:water (85:15, v/v), using an Ultra-Turrax® homogeniser. Mycotoxins were then identified and quantified by liquid chromatography (LC) with diode array detection (DAD). Positive samples were confirmed by LC–MS/MS. Analytical results showed that the percentages of analysed samples contaminated with total ENs, FUS and BEA were 30.8%, 10.3% and 5.8%, respectively. ENA1 was the mycotoxin most often found: ENA1 levels ranged between 37.5 and 688mg/kg. FUS and BEA were present in levels lower than 7.4 and 10.6mg/kg, respectively. This is the first international report on the presence of emerging Fusarium mycotoxins in breakfast cereals and infant cereals. [ABSTRACT FROM AUTHOR]

Abstract: Enniatins (ENs) are antibiotic compounds of hexadepsipeptidic structure produced by several strains of Fusarium spp. The ENs A, A1, B, B1 were purified from extracts of Fusarium tricinctum grown on a solid medium of corn, by a low pressure liquid chromatography (LPLC) on reverse phase of Amberlite XAD-7 followed by semipreparative LC. The purity and the structure of the isolated compounds were confirmed by LC–MS/MS. The technique of the purification of the fungal extract enabled complete separation of the ENs A, A1, B, B1 with a mean purity of 97% for all the compounds. The cytoxicity of the ENs was tested in the cell lines of human origin (epithelial colorectal adenocarcinoma cells, Caco-2) by MTT assays. Only EN A1 and B1 evoked toxicity at the tested concentrations. The inhibitory concentration (IC50) for EN A1 on Caco-2 cells was 12.3 μM, whereas the IC50 produced by the EN B1 was 19.5 μM. This study indicates that ENs, fungal metabolites that are commonly found in corn and in general in product composed by corn, may have a toxic potential for human health. [Copyright &y& Elsevier]

Abstract: A method for determination of zearalenone in cereal flour has been developed applying pressurized liquid extraction (PLE) using methanol/acetonitrile (50:50v/v) as the extraction solvent. The extracted samples were analyzed with liquid chromatography coupled to mass spectrometry (LC–MS) with an electro spray ionisation interface (ESI). The method was validated as a quantitative confirmatory method according to the Eu Commission Decision 2002/657/EC. Recoveries of the extraction step data were satisfactory with values higher then 70%. Quantification limits (LOQ) were 5μg/kg for ESI (+) and 1μg/kg for ESI (−). Twenty one flour samples produced in different countries were extracted and analyzed by LC–MS (ESI) negative ionisation followed by LC–MS (ESI) positive ionisation for confirmative purposes, quantification was based on matrix-matched standard curves to compensate disturbing matrix effect. Only one sample was confirmed containing zearalenone below levels regulated by European Commission. [Copyright &y& Elsevier]

Two approaches based on sorptive extraction, solid-phase microextraction (SPME) and stir bar sorptive extraction (SBSE), in combination with liquid chromatography (LC)–atmospheric pressure chemical ionization mass spectrometry (MS) have been assayed for analyzing chlorpyriphos methyl, diazinon, fonofos, phenthoate, phosalone, and pirimiphos ethyl in honey. In both, SPME and SBSE, enrichment was performed using a poly(dimethylsiloxane) coating. Significant parameters affecting sorption process such as sample volume, sorption and desorption times, ionic strength, elution solvent, and dilution (water/honey) proportion were optimized and discussed. Performance of both methods has been compared through the determination of linearity, extraction efficiencies, and limits of quantification. Relative standard deviations for the studied compounds were from 3 to 10% by SPME and from 5 to 9% by SBSE. Both methods were linear in a range of at least two orders of magnitude, and the limits of quantification reached ranging from 0.04 to 0.4 mg kg−1 by SBSE, and from 0.8 to 2 mg kg−1 by SPME. The two procedures were applied for analyzing 15 commercial honeys of different botanical origin. SPME and SBSE in combination with LC–MS enabled a rapid and simple determination of organophosphorus pesticides in honey. SBSE showed higher concentration capability (large quantities of sample can be handled) and greater accuracy (between 5 and 20 times) and sensitivity (between 10 and 50 times) than SPME; thus, under equal conditions, SBSE is the recommended technique for pesticide analysis in honey. [Copyright &y& Elsevier]

A liquid chromatography (LC) method for the quantitative determination of five fungicide residues (dichloran, flutriafol, o-phenylphenol, prochloraz and tolclofos methyl) in oranges, lemons, bananas, peppers, chards and onions is described. The residues were extracted by matrix solid-phase dispersion (MSPD) using C8. Quantitative analysis was performed by isocratic LC coupled to quadrupole mass spectrometer using atmospheric pressure chemical ionization in the negative ionization mode. The limit of quantification was 0.01 mg kg−1 for flutriafol, o-phenylphenol and dichloran, and 0.1 mg kg−1 for prochloraz and tolclofos methyl. The MSPD method is also suitable for LC–UV analysis but higher limits of quantification (between 1 and 5 mg kg−1) were obtained. Validation of the method was performed between 0.01 and 25 mg kg−1. Recoveries for fungicides ranged from 52.5 to 91.1% with relative standard deviations between 6.1 and 11.9%. The method was applied to the determination of residues in samples taken from agricultural cooperatives. The fungicides most often detected were o-phenylphenol and prochloraz. [Copyright &y& Elsevier]

Enniatins (ENs) are emerging mycotoxins produced by Fusarium fungi which are cytotoxic also at low concentrations due to its ionophoric properties. The aim of this study was to evaluate the hepatic toxicity of ENs exposure at different concentrations in Wistar rats through a proteomic approach. Animals were intoxicated by oral gavage with medium (EN A 256, ENA1 353, ENB 540, ENB1 296 μg/mL) and high concentrations (ENA 513, ENA1 706, ENB 1021, ENB1 593 μg/mL) of an ENs mixture and sacrificed after 8 h. Protein extraction was performed using powdered liver. Peptides were analyzed using a liquid chromatography coupled with a quadrupole time-of-flight mass spectrometer. Proteins were filtered by abundance using Mass Professional Profiler software (Agilent Technologies) and 57 were differentially expressed when compared to the control. In terms of abundance, the liver biomarker Carboamoyl-phosphate synthase showed the highest levels in all conditions employed while actin-1 had the lowest. Bioinformatic analysis using DAVID platform reported acetylation, nucleotide phosphate-binding region:NAD and catalytic activity as the most represented terms. Furthermore, metabolism was the most significant and enriched pathway in Reactome overrepresentation. In conclusion, ENs acute exposure caused protein expression changes related to major cellular processes in rats, hinting its involvement in liver disturbance. • Metabolism pathway in liver was the most enriched after ENs exposure in vivo. • Four proteins related to oxidoreductase and antioxidant activities are upregulated. • Liver injury biomarker CPS-1 is increased expression in ENs exposed rat livers. [ABSTRACT FROM AUTHOR]