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Aspergillus carbonarius is an important ochratoxin A (OTA)-producing fungus that is responsible for toxin contamination of grapes and wine, coffee and cocoa. A suppression subtractive hybridization (SSH) approach was performed with two strains of A. carbonarius, antagonistic in their OTA-production ability, to identify genes whose expression is linked with the ability to produce OTA. BlastX analysis identified 109 differentially-expressed sequences putatively involved in the production of OTA, with significant similarities (Evalue < 10− 5) to sequences deposited in the NCBI non-redundant protein database. Of the 109 ESTs, 26% were involved in regulation processes, 15% corresponded to hypothetical proteins, 12% were involved in stress response and detoxification, 9% corresponded to transport and secretion processes, 7% corresponded to amino acid metabolism, 7% were involved in hydrolysis of energy reserves and 5% involved in secondary metabolism. Other unisequences showed homology to genes involved in protein synthesis and general metabolism. According to their sequence similarities to genes in the NCBI database, the possible functional roles they might play in the production and regulation of OTA are discussed. Worth noting is the high percentage of genes involved in regulation, including specific and global regulators. It is also important to note the high percentage of genes involved in the response to stress and detoxification. ; This research was supported by grants from the Generalitat Valenciana (GV2004-B-195) and the Spanish Government (AGL2005-00707/ALI) ; Peer reviewed

A bibliographic review was made about the presence of ochratoxin A (OTA) in cocoa and cocoa products, its effects in human health, forms of detections, permitted legal levels, preventive and control measures, to make a extension of knowledge of each actor in the value chain (as farmer, sellers, manufacturers, exporters, the government, customers and so on) respect to this important topic and its relation with human health, as well as, stimulate to farmers and processors, use of code of practice. ; Se realizó una revisión bibliográfica sobre los riesgos que implica la presencia de ocratoxina A (OTA) en cacao y sus derivados, su efecto en la salud del ser humano, las formas de detección, los niveles permisibles y las medidas preventivas y de control, con la finalidad de informar a los actores de la cadena de valor (productores, comercializadores, procesadores, exportadores, gobiernos, consumidores finales, entre otros) sobre la importancia del tema por su relación directa con la salud de los consumidores, así como incentivar, a los agricultores y procesadores, el uso del código de prácticas.

Spices are a popular ingredient in cuisine worldwide but can pose a health risk as they are prone to fungal infestation and mycotoxin contamination. The purpose of this study was to evaluate ochratoxin A (OTA) in 54 single-kind traditional and less traditional spices, each of which was purchased in six samples of different batches (324 samples in total) at the Czech market during 2019–2020. The HPLC-FLD method with pre-treatment by immunoaffinity columns was employed to determine OTA. The limits of detection and quantification were 0.03 ng g(−1) and 0.10 ng g(−1), respectively. A total of 101 (31%) samples of 19 spice kinds were positive at concentrations ranging from 0.11–38.46 ng g(−1). Only turmeric was contaminated with an OTA level exceeding the European Union limits. However, most spices have no regulation, thus further extensive monitoring of various mycotoxins in various kinds of spices is necessary. Chilli and black pepper are the most studied spices for OTA contamination, however, many other kinds of spice can also be highly contaminated, but studies on them are less common, rare, or have not yet been performed. The uniqueness of this study lies in the wide range of spice types studied for the presence of OTA on the Czech market.

An impedimetric label-free immunosensor on disposable screen-printed carbon electrodes (SPCE) for quantitative determination of Ochratoxin A (OTA) has been developed. After modification of the SPCE surface with gold nanoparticles (AuNPs), the anti-OTA was immobilized on the working electrode through a cysteamine layer. After each coating step, the modified surfaces were characterized by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). The capacitance was chosen as the best parameter that describes the reproducible change in electrical properties of the electrode surface at different OTA concentrations and it was used to investigate the analytical parameters of the developed immunosensor. Under optimized conditions, the immunosensor showed a linear relationship between 0.3 and 20 ng/mL with a low detection limit of 0.25 ng/mL, making it suitable to control OTA content in many common food products. Lastly, the immunosensor was used to measure OTA in red wine samples and the results were compared with those registered with a competitive ELISA kit. The immunosensor was sensitive to OTA lower than 2 μg/kg, which represents the lower acceptable limit of OTA established by European legislation for common food products.

[EN] Aptamers have been used as recognition elements for several molecules due to their great affinity and selectivity. Additionally, mesoporous nanomaterials have demonstrated great potential in sensing applications. Based on these concepts, we report herein the use of two aptamer¿capped mesoporous silica materials for the selective detection of ochratoxin¿A (OTA). A specific aptamer for OTA was used to block the pores of rhodamine¿B¿loaded mesoporous silica nanoparticles. Two solids were prepared in which the aptamer capped the porous scaffolds by using a covalent or electrostatic approach. Whereas the prepared materials remained capped in water, dye delivery was selectively observed in the presence of OTA. The protocol showed excellent analytical performance in terms of sensitivity (limit of detection: 0.5¿0.05¿nm), reproducibility, and selectivity. Moreover, the aptasensors were tested for OTA detection in commercial foodstuff matrices, which demonstrated their potential applicability in real samples ; We thank the Spanish Government (projects MAT2015-64139-C4-1-R and AGL2015-70235-C2-2-R (MINECO/FEDER)) and the Generalitat Valenciana (project PROMETEOII/2014/047) for support. A.R. thanks UPV for her predoctoral fellowship. S.S. thanks the Instituto de Salud Carlos III and the European Social Fund for the financial support "Sara Borrell" (CD16/000237). A.B. thanks the Spanish Government for financial support by the "Juan de la Cierva-Incorporacion" (IJCI-2014-21534). The authors also thank the Electron Microscopy Service at UPV for support. ; Ribes, À.; Santiago Felipe, S.; Bernardos Bau, A.; Marcos Martínez, MD.; Pardo Vicente, MT.; Sancenón Galarza, F.; Martínez-Máñez, R. (2017). Two New Fluorogenic Aptasensors Based on Capped Mesoporous Silica Nanoparticles to Detect Ochratoxin A. ChemistryOpen. 6(5):653-659. https://doi.org/10.1002/open.201700106 ; S ; 653 ; 659 ; 6 ; 5

L'articolo è disponibile sul sito dell'editore: http://www.pubs.acs.org ; Ochratoxin A (OTA) is a potent nephrotoxin and renal carcinogen in rats, but the mechanism of OTA tumorigenicity is unknown. Ochratoxin A has been shown to be negative in many genetic toxicology test in vitro. However, the potential of OTA to induce genotoxic effects has not been investigated in male rats, the most sensitive species for OTA-induced tumor formation. In this study, male F344 rats were repeatedly administered OTA (0, 250, 500, 1000, and 2000 íg/kg of body wt) or the non-chlorinated analogue ochratoxin B (OTB; 2000 íg/kg of body wt) for 2 weeks (5 days/week), and DNA breakage was analyzed in target and nontarget tissues using the comet assay both in the absence and presence of formamidopyrimidine-DNA (Fpg) glycosylase. Potential DNA-adduct formation was also analyzed in the target organ kidney by 32P-postlabeling using two different solvent systems. DNA-strand breaks were evident in liver, kidney, and spleen of animals treated with OTA, and a similar degree of DNA damage was observed in rats treated with OTB, despite the lower toxicity of OTB. Moreover, the presence of DNA damage did not correlate with histopathological alterations, which were evident in the kidney but not in the liver. In liver and kidney, the extent of DNA damage was further enhanced in the presence of Fpg glycosylase, which is known to convert oxidative DNA damage into strand breaks, suggesting the presence of oxidative DNA damage. Oxidative DNA damage as a mechanism of OTA-dependent DNA damage is consistent with the absence of lipophilic DNA adducts as assessed by 32P-postlabeling analysis. No spots indicative of OTA-related DNA adducts were observed in kidney DNA extracted from OTA-treated animals by 32P-postlabeling analysis, despite the use of synthetic standard for postulated adducts. A small, but not significant, increase in the incidence of chromosomal aberrations (essentially chromatid and chromosome-type deletions) was observed in splenocytes from rats treated with OTA in vivo and subsequently cultured in vitro to express chromosomal damage. These aberrations are also compatible with oxidative DNA lesions since they are not typically caused by chemical carcinogens which form covalent DNA adducts. Together, with the lack of evidence for formation of lipophilic DNA adducts as assessed by postlabeling, these data suggest that OTA may cause genetic damage in both target and nontarget tissues independent of direct covalent binding to DNA. ; Parts of this work were supported by the Fifth RTD Framework Program of the European Union, Project No. QLK1-2001-01614 and by USPHS Grant CA77114.

Wine quality is a complex, multi - layered conception consisting of numerous factors such as sensory characteristics, chemical composition, legislation, market - consumer, with hygienic - toxicological factor being of special importance due to growing demands for health safe foods. This paper shows the results of studies carried out up till now concerning the mycotoxins in wine (Aflatoxins, Trichothecens, Patulin), with special attention paid to ochratoxin A, most frequently present in grapes, must and wine, and to the influence of certain technological operations and processes during wine making. Due to its high toxicity, the presence of ochratoxin A has been limited to 2 μg/l by EU EG regulation 123/2005. ; Kvalitet vina je kompleksan, višeslojni pojam sastavljen od većeg broja činilaca poput senzorskih karakteristika, hemijskog sastava, zakonodavno-pravnog, tržišno-potrošačkog, pri čemu higijensko-toksikološki ima poseban značaj s obzirom na sve izraženije zahteve za zdravstveno bezbednom hranom. U radu su prikazani rezultati dosadašnjih istraživanja mikotoksina u vinu (aflatoksini, trihotecen, patulin), pri čemu je posebna pažnja posvećena najčešće prisutnom ohratoksinu A na grožđu, u širi i vinu i uticaj pojedinih tehnoloških operacija i procesa u toku proizvodnje vina na njegov sadržaj. S obzirom na njegovu visoku toksičnost Evropska Unija EG regulativom 123/2005. svela je najviše dozvoljenu količinu ohratoksina A na 2 μg/l.

Wine quality is a complex, multi - layered conception consisting of numerous factors such as sensory characteristics, chemical composition, legislation, market - consumer, with hygienic - toxicological factor being of special importance due to growing demands for health safe foods. This paper shows the results of studies carried out up till now concerning the mycotoxins in wine (Aflatoxins, Trichothecens, Patulin), with special attention paid to ochratoxin A, most frequently present in grapes, must and wine, and to the influence of certain technological operations and processes during wine making. Due to its high toxicity, the presence of ochratoxin A has been limited to 2 μg/l by EU EG regulation 123/2005. ; Kvalitet vina je kompleksan, višeslojni pojam sastavljen od većeg broja činilaca poput senzorskih karakteristika, hemijskog sastava, zakonodavno-pravnog, tržišno-potrošačkog, pri čemu higijensko-toksikološki ima poseban značaj s obzirom na sve izraženije zahteve za zdravstveno bezbednom hranom. U radu su prikazani rezultati dosadašnjih istraživanja mikotoksina u vinu (aflatoksini, trihotecen, patulin), pri čemu je posebna pažnja posvećena najčešće prisutnom ohratoksinu A na grožđu, u širi i vinu i uticaj pojedinih tehnoloških operacija i procesa u toku proizvodnje vina na njegov sadržaj. S obzirom na njegovu visoku toksičnost Evropska Unija EG regulativom 123/2005. svela je najviše dozvoljenu količinu ohratoksina A na 2 μg/l.

In this work, we report a novel method of label-free detection of small molecules based on direct observation of interferometric signal change in graphene-modified glasses. The interferometric sensor chips are fabricated via a conventional wet transfer method of CVD-grown graphene onto the glass coverslips, lowering the device cost and allowing for upscaling the sensor fabrication.For the first time, we report the use of graphene functionalized by the aptamer as the bioreceptor, in conjunction with Spectral-Phase Interferometry (SPI) for detection of ochratoxin A (OTA). In a direct assay with an OTA-specific aptamer, we demonstrated a quick and significant change of the optical signal in response to the maximum tolerable level of OTA concentration. The sensor regeneration is possible in urea solution. The developed platform enables a direct method of kinetic analysis of small molecules using a low-cost optical chip with a graphene-aptamer sensing layer. ; This work was supported in part by the IPANEMA project, which received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement N° 872662, in part by the REALSENSE1: Monitoring of cell culture parameters using sensors for biomass and nutrients/metabolites in media: Lab-on-a-Chip (LOC) approach, Good Food Institute 2018 Competitive Grant Program, in part by the EU H2020 Graphene Flagship Core 3 Grant No. 881603, in part by the Russian Science Foundation under grant number 19-19-00401 (graphene chip development) and grant of the Ministry of Science and Higher Education of the Russian Federation for large scientific projects in priority areas of scientific and technological development (registration number 2020-1902-01-222, subsidy identifier 075-15-2020-774). I.G. and I.B. participated in a project that has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement N° 739570 (ANTARES).

International audience The cell wall of Saccharomyces cerevisiae can bind mycotoxins in vitro but there is scarce information on whether this property decreases the absorption of mycotoxins in vivo. The effect of a yeast cell wall preparation (YCW) on toxicokinetics and balance excretion (urine and faeces) of aflatoxin B1 (AFB1) and ochratoxin A (OTA) was tested in rats after oral administration of each toxin. The 3H-labelled mycotoxins were used at low doses. Co-administration of YCW with AFB1 decreased the extent but not the rate of absorption. Concurrently, radioactivity excreted in faeces increased by up to 55% when compared to controls, whilst the excretion in urine decreased (p OTA). In conclusion, these results indicate that YCW could be used to protect monogastric animals against exposure to low dietary levels of selected mycotoxins.

The contamination of food commodities by fungal toxins has attracted great interest because many of these mycotoxins are responsible for different diseases, including cancer and other chronic illnesses. Ochratoxin A (OTA) is a mycotoxin naturally present in food, and long-term exposure to food contaminated with low levels of OTA has been associated with renal cancer. In the present study, the cytotoxicity, cytostaticity, and genotoxicity of OTA (0.075-15 μM) in human lymphocytes were evaluated. A comet assay, a modified comet assay (DNA repair assay), which uses N-hydroxyurea (NHU) to detect nonrepaired lesions produced by OTA, and a cytokinesis-blocked micronucleus assay were used. Treatments with OTA were not cytotoxic, but OTA caused a cytostatic effect in human lymphocytes at a concentration of 15 μM. OTA (0.075-5 μM) produced a slight increase in the percentage of DNA in the comets and a delay in the DNA repair capacity of the lymphocytes. Micronucleus (MN) induction was observed at OTA concentrations of 1.5 and 5 μM. Our results indicate that OTA induces DNA stable damage at low doses that are neither cytotoxic nor cytostatic, and OTA delays the DNA repair kinetics. These findings indicate that OTA affects two pivotal events in the carcinogenesis pathway. ; The authors are grateful to the Spanish (Project AGL2011-24862) and Catalonian (XaRTA-Reference Network on Food Technology) Governments for their financial support. C.A. González-Arias thanks the Secretaria de Universitats i Recerca del Departament de Economia i Coneixement of the Generalitat de Catalunya for the pre-doctoral grant. The authors also thank Q.F.B. Guillermina Vázquez Estrada, Francisco Alberto Verdín Betancourt, and Carlos Alberto Martínez Delgado for their technical assistance.