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A new method based on a QuEChERS extraction followed by the ultra-high liquid chromatography tandem mass spectrometry (UPLC-MS/MS) detection has been developed for the analysis of mycotoxin in beer. The method allows the identification and quantification of 23 mycotoxins with different chemical characteristic including regulated, emerging and masked compounds. A sample treatment procedure involving a QuEChERS extraction and dispersive solid-phase clean-up steps was applied. This protocol involves a new approach based on a sample concentration before the extraction. The method was in-house validated in terms of limits of detection (LODs), limits of quantification (LOQs), linearity, repeatability and recoveries. For most compounds, recoveries ranged from 70% to 110% with LOQs (from 0.038 to 30.43 µg/L) lower than the maximum residue levels established in European regulations. In general, acceptable performance characteristics were obtained fulfilling the current legislation. Therefore, the proposed method is appropriate for routine analysis of beer.

A simple method for the quantification of 40 mycotoxins in milk was developed. This method is based on a QuEChERS extraction followed by the ultra-high liquid chromatography tandem mass spectrometry (UHPLC-MS/MS) detection, and allows the simultaneous analysis of regulated, emerging, and modified mycotoxins. A sample treatment procedure was optimized to include a concentration step for the analysis of some compounds such as aflatoxin M1. The method was in-house validated in terms of limits of detection (LODs), limits of quantification (LOQs), linearity, recoveries, and precision. LOQs lower than 10 ng/mL were obtained, and recoveries ranged from 61% to 120% with a precision, expressed as the relative standard deviation, lower than 15%. Therefore, acceptable performance characteristics were obtained fulfilling European regulations. The method was successfully applied for the quantification of mycotoxins in raw milk. It can be highlighted high occurrence of beauvericin and enniatins were found in low amounts.

Bunch rot of Vitis vinifera is frequently caused by a complex of filamentous fungi. In a study on non-Botrytis fungi associated with bunch rot at harvest in northwestern Spain, rotting berries showing pink masses were observed in bunches of V. vinifera Albarino in one vineyard that experienced prolonged warm, moist conditions before harvest. The aim of this work was to identify the fungal species and determine its pathogenicity on grapes. Fungal isolates not corresponding morphologically to any known genus associated with bunch rot were obtained from the pink masses. Morphological and molecular phylogenetic analyses revealed that the isolates belonged to Pilidium lythri, an opportunistic pathogen causing tan-brown rot on strawberry. Most frequent non-Botrytis grape-rotting fungi at the vineyard were Penicillium brevicompactum, Penicillium expansum, and Talaromyces purpurogenus, while P. lythri had a low isolation frequency. Pathogenicity tests showed that P. lythri caused tan-brown rot in berries of the V. vinifera table grape varieties Regal Seedless and Red Globe. That P. lythri can directly infect healthy grape berries suggests that it may be a true pathogen associated with bunch rot on grapevine. Its presence on berries may contribute to postharvest decay of table and wine grapes.

This paper examined salinity changes in soil in a greenhouse over four cropping cycles of lettuce (two autumn-winter cycles followed by two spring-summer cycles), testing the effect of applying an ...

A new multi-mycotoxin analysis method was developed to identify and quantify 22 mycotoxins in multiple feed matrices. This method is based on a QuEChERS (quick, easy, cheap, effective, rugged and safe) extraction procedure followed by the ultra-high liquid chromatography tandem mass spectrometry (UHPLC-MS/MS) detection. The QuEChERS extraction procedure was optimized for minimizing the matrix effect of maize. Obtained recoveries ranged from 67 % to 94 % and low LOQs (from 0.22 to 32.64 μg/kg) for regulated and emerging mycotoxins were obtained. Then, the method was expanded to seven raw materials and eight feedstuffs. In these matrices, the recovery for most mycotoxins was also high enough to fulfill the current legislation. The developed method was used for the analysis of 75 samples obtained from a nearby feed factory. Maize and maize-based products showed the highest occurrence of mycotoxins, although always below the legal limit. In addition, the ability of spheres of different composition and size to eliminate mycotoxins from raw materials and feedstuffs was tested. Up to 28 % of the mycotoxin content can be removed from matrices by using glass spheres of 2 mm of diameter. Therefore, a new process for the physical removal of mycotoxins was developed.

Marine and freshwater toxins contaminate water resources, shellfish and aquaculture products, causing a broad range of toxic effects in humans and animals. Different core-shell nanoparticles were tested as a new sorbent for removing marine and freshwater toxins from liquid media. Water solutions were contaminated with 20 μg/L of marine toxins and up to 50 μg/L of freshwater toxins and subsequently treated with 250 or 125 mg/L of nanoparticles. Under these conditions, carbon nanoparticles removed around 70% of saxitoxins, spirolides, and azaspiracids, and up to 38% of diarrheic shellfish poisoning toxins. In the case of freshwater toxins, the 85% of microcystin LR was eliminated; other cyclic peptide toxins were also removed in a high percentage. Marine toxins were adsorbed in the first 5 min of contact, while for freshwater toxins it was necessary 60 min to reach the maximum adsorption. Toxins were recovered by extraction from nanoparticles with different solvents. Gymnodinium catenatum, Prorocentrum lima, and Microcystis aeruginosa cultures were employed to test the ability of nanoparticles to adsorb toxins in a real environment, and the same efficacy to remove toxins was observed in these conditions. These results suggest the possibility of using the nanotechnology in the treatment of contaminated water or in chemical analysis applications.

Se evaluó el potencial fertilizante de un estiércol deshidratado y granulado de pollo (Broiler Litter, BL) en un cultivo de lechuga en invernadero. Se establecieron dos ensayos, uno en el periodo otoño-invierno, y otro en primavera. Se aplicaron distintos tratamientos fertilizantes: parcelas no fertilizadas (Control), fertilizadas con nitrato amónico (M, 120 kg N ha-1), fertilizadas con un fertilizante mineral de liberación lenta (Mr, 120 kg N ha-1) y con dosis crecientes de BL para satisfacer las necesidades de N de la lechuga (60, 80, 120 y 240 kg N ha-1 en otoño-invierno y 120, 240 y 360 kg N ha-1 en primavera). El abono se incorporó al comienzo de ambos ensayos, en una sola aplicación, lo que permitió estudiar el efecto residual en una segunda cosecha para ambas épocas. En los dos ensayos, de otoño-invierno y de primavera, la fertilización con BL, a cualquiera de las dosis aplicadas, garantizó la producción del cultivo de lechuga, del mismo modo o incluso superior al abonado mineral. El fertilizante BL se comportó como un abono de liberación gradual, proporcionando una cantidad importante de nitrógeno para las segundas cosechas, fruto del efecto residual del abonado aplicado dos meses antes. La fertilización con BL en dosis superiores a 120 kg de N ha-1 para el periodo otoño-invierno y primavera suministraron nutrientes suficientes para obtener un segundo ciclo con un alto porcentaje de lechugas comerciales.

Se estudió la producción y calidad de pimiento tipo Lamuyo en invernadero abonado con estiércol de pollo deshidratado y granulado (BL), así como las modificaciones producidas en suelo tras su cultivo. Se estableció un cultivo de pimiento tipo Lamuyo, cultivar `Vidi F1´ para el cual se aplicaron, al azar, seis tratamientos fertilizantes (3 bancales por tratamiento): un tratamiento control que no recibió fertilización (C), aplicación de 83,3 g m-2 del fertilizante mineral de liberación lenta, para suministrar 100 kg N ha-1 (Mr), y aplicación de 4 dosis crecientes de un estiércol de pollo peletizado (BL1: 265,9, BL2: 354,5, BL3: 443,2 y BL4: 531,8 g m-2) para proporcionar respectivamente 60, 80, 100 y 120 kg N ha-1 (BL1, BL2, BL3 y BL4). Con dosis no superiores a 265,9 g m-2 de estiércol de pollo (BL1), se obtuvieron producciones de pimiento similares a las conseguidas con la fertilización mineral. En relación a la calidad nutritiva del fruto, el abonado, tanto mineral como orgánico, no originó diferencias significativas en el contenido de vitamina C. Los suelos abonados con el estiércol de pollo deshidratado y granulado, a cualquiera de las dosis estudiadas (BL1, BL2, BL3 y BL4), no presentaron signos de salinización.

The large impacts of global warming projected on crops worldwide will subsequently influence not only food security, by reducing yields and thus food availability, but food and feed safety, mycotoxins being considered one of the most important food safety hazards affected by climate change. Future changes in temperature, precipitation, and atmospheric CO2 concentration are expected to carry along an increased risk of mycotoxin contamination of cereal crops in the field and might have an impact on the geographical distribution of certain cereals, mycotoxigenic fungi and their mycotoxins.

A method based on the combined use of ultraperformance liquid chromatography coupled to mass spectrometry–ion trap–time-of-flight (UPLC–MS–IT–TOF) detection was employed to identify the metabolite production of Aspergillus ochraceus, which is the major cause of food and feed contamination due to ochratoxin A. Under the proposed chromatographic conditions, seven metabolites belonging to the family of circumdatins were separated and identified. Their initial identification was performed through the exact molecular formula, as a function of their accurate mass. Collision-induced dissociation was applied to predict precursor and product ions, and the elemental composition of each compound was obtained. The elimination of nitrogenous groups followed by successive losses of carbonyl groups is the common fragmentation pathway of circumdatins. With the fragmentation data obtained, an UPLC–MS/MS method was created and optimized to detect circumdatins in corn samples.

Mycotoxins occur naturally as agricultural contaminants all over the world. The toxic effects of some of their metabolites are known and their presence regulated in food and feed. This paper describes two methods for the detection of toxins of type-A trichothecenes group, and their modified forms, using mass spectrometry. Ultra-performance liquid chromatography coupled to mass spectrometry-ion trap-time of flight (UPLC-MS-IT-TOF) was employed to characterize the fragmentation pathways of 10 type-A trichothecenes, and characteristic ions were tentatively identified in scan mode through their accurate masses. Unknown signals were detected in a F. sporotrichioides extract, which afterwards were identified as seven modified forms of neosolaniol (NEO) and T-2 toxin. Then, UPLC coupled to tandem mass spectrometry (MS/MS) was employed to develop a precursor ion scanning method that can be used as a screening tool to detect any modified type-A trichothecenes.

This chapter focuses on the analysis of the main natural toxins associated with food safety. Mycotoxins are produced primarily by fungi of the genera Fusarium, Aspergillus, Penicillium, Claviceps, and Alternaria. The main representatives are aflatoxins, ochratoxin A, patulin, trichothecenes, zearalenone, fumonisins, and ergot alkaloid. Marine toxins are produced primarily by dinoflagellates of several genera. The main toxins are classified on the basis of the main toxin content: okadaic acid and dinophysistoxins, azaspiracids, yessotoxins, pectenotoxins, domoic acid, and saxitoxin and gonyautoxins. Cyanotoxins are produced by blue-green microalgae classified according to their effect: hepatotoxins (microcystins (MCs), nodularins and cylindrospermopsins), neurotoxins (anatoxin-a and analogs, saxitoxins, and s-. N-methylamino-. l-alanine), and dermatotoxins (aplysiatoxins and lyngbyatoxins). Finally, tetrodotoxin is produced by bacteria and it is a concern in fish and shellfish. All these toxins are analyzed mostly by LC-MS, and the specific features of the analysis is discussed in the chapter.