Trichotecenes in breakfast cereals from the Spanish retail market

[EN] Deoxynivalenol (DON), nivalenol (NIV), 3-acetyl-DON (3-AcDON), 15-acetyl-DON (15-AcDON) and fusarenone X (Fus-X) were analysed in 148 breakfast cereal samples collected from the Spanish retail market. The samples were taken from the products most commonly consumed by the Spanish population. Major ingredients included corn, wheat and rice, alone or mixed. The trichothecenes were extracted with acetonitrile:water (84:16, v/v). The extracts were cleaned by means of Mycosep 227 columns. For analysis gas chromatography-mass spectrometry (GC-MS) after derivatisation to trimethylsilyl ethers was utilised. Mean recovery values, obtained from different matrices of cereal samples spiked with trichothecenes ranged from 69% to 110% with relative standard deviation lower than 10%. The estimated limits of detection and quantification, calculated at a signal-to-noise ratio of 3:1 and of 6:1, respectively, were between 8.90 and 14.7 mu g/kg, and between 15.2 and 23.6 mu g/kg, respectively. DON was the most frequently detected mycotoxin and was usually present at the highest concentration. NW and Fus-X were detected in 4 and 2 samples, respectively; 3- and 15-AcDON were not detected. The calculated dietary intake was compared to tolerable daily intake (TDI) values. The survey demonstrated a regular occurrence of low levels of trichothecenes in breakfast cereals on the Spanish market. (C) 2012 Elsevier Inc. All rights reserved.This work has been financed by the Spanish Comision Interministerial de Ciencia y Tecnologia (Project Ref. AGL2004-07549-C05-04) whose support is gratefully acknowledged.Montes Estellés, RM.; Segarra Guerrero, RO.; Castillo López, MÁ. (2012). Trichotecenes in breakfast cereals from the Spanish retail market. Journal of Food Composition and Analysis. 27(1):38-44. https://doi.org/10.1016/j.jfca.2012.05.004S384427

Quinolones in goats' milk: Effect on the cheese-making process, chemical and microbial characteristics of acid-coagulated cheeses

[EN] The effect of the presence in goats' milk of enrofloxacin and ciprofloxacin on cheese-making and the characteristics of acid-coagulated cheeses was evaluated. Raw goats' milk was spiked with quinolones at maximum residue limit concentration (100 ¿g kg¿1). For each antibiotic, three batches of cheese were made by acid coagulation (pH 4.6) using a commercial starter culture. Cheese-making process, gross composition and microbial counts in the cheeses were unaffected by the presence of quinolones in milk. However, relatively high amounts of these substances were retained in the cheeses, with residual concentrations of 146.5 ± 4.9 ¿g kg¿1 and 150.7 ± 25.7 ¿g kg¿1 for enrofloxacin and ciprofloxacin, respectively, after 20 days of maturation. Results suggest that the use of goats' milk containing legally admissible amounts of enrofloxacin and/or ciprofloxacin would have no impact on cheese manufacturing, composition and microflora of acid-coagulated cheese. However, the transfer of these substances to the final products could compromise consumer safety.The authors are grateful for the financial support by the Ministerio de Ciencia e Innovacion (Madrid, Spain) project AGL-2013-45147-R.Beltrán Martínez, MC.; Sanna, A.; Molina Pons, MP.; Quintanilla, P.; Montes-Estellés, RM. (2023). Quinolones in goats' milk: Effect on the cheese-making process, chemical and microbial characteristics of acid-coagulated cheeses. International Dairy Journal. 138. https://doi.org/10.1016/j.idairyj.2022.10553813

Detection and enumeration of viable Listeria monocytogenes cells from ready-to-eat and processed vegetable foods by culture and DVC-FISH

Listeria monocytogenes is an important agent of foodborne disease, showing low prevalence but high mortality. There is evidence that vegetables are important vehicles of transmission, especially those minimally processed (fresh, fresh-cut vegetables under modified atmosphere packaging (MAP) or frozen) and directly exposed to consumers. The aim of this work was to detect and enumerate viable . L. . monocytogenes cells by culture and molecular methods from vegetable foods.A total of 191 vegetable samples (fresh, frozen and fresh-cut under modified atmosphere packaging) were studied. . L. monocytogenes was detected and identified by selective plating, PCR and DVC-FISH.An isolation rate of 4.19% was obtained by culture, with a higher incidence in frozen vegetables. Six isolates belonged to serotype 1/2a and 2 to 4b. Counts were below <100 cfu/g for the eight positive samples, according to the food safety criteria established for the RTE by Commission Regulation EC No 1441/2007.Multiplex PCR method yielded a greater number of positive samples (10.47%). DVC-FISH technique determined that viable cells of L. monocytogenes were present in 32.98% of the samples, containing up to 4.97 log 10 viable cells/g. © 2012 Elsevier Ltd.This work was supported by the grant AGL2008-05275-C03-02 (national and FEDER funds) from Ministerio de Ciencia e Innovacion, Spain.Moreno Trigos, MY.; Sánchez Contreras, J.; Montes Estellés, RM.; García Hernández, J.; Ballesteros, L.; Ferrús Pérez, MA. (2012). Detection and enumeration of viable Listeria monocytogenes cells from ready-to-eat and processed vegetable foods by culture and DVC-FISH. Food Control. 27(2):374-379. https://doi.org/10.1016/j.foodcont.2012.04.01737437927

Occurrence of deoxynivalenol and nivalenol in Spanish corn-based food products

[EN] The aim of the present work was to evaluate the occurrence of trichothecenes toxins, deoxynivalenol (DON) and nivalenol (NIV) in samples of corn-based foods (breakfast cereals and snacks) consumed by the Spanish population. A total of 175 commercially available samples were randomly collected during 2005. Trichothecenes were determined by a gas chromatography¿electron capture detector. The estimated limit of quantification was 25.4 mg/kg for DON and 15.9 mg/kg for NIV. DON was detected in 22 of the 55 samples of breakfast cereals, in 13 of the 57 samples of baked corn snacks and in 12 of the 63 samples of fried corn snacks. NIV was detected in 6 samples of breakfast cereals and 1 sample of snacks. The median concentrations of DON and NIV found in all samples were 53.9 and 60.2 mg/kg, respectively. The influence of different factors, such as the presence of additional ingredients and the type of commercial brand, on the toxin incidence and content levels were also studied. The values of both mycotoxin intake found in this study are lower than the proposed tolerable daily intake for the respective toxin (1 and 0.7 mg/kg bw/day for DON and NIV, respectively).This work has been financed by the Spanish Comisión Interministerial de Ciencia y Tecnología (Project Ref. AGL2004- 07549-C05-04) whose support is gratefully acknowledgedCastillo López, M.; Montes Estellés, RM.; Navarro, A.; Segarra, R.; Cuesta, G.; Hernandez, E. (2008). Occurrence of deoxynivalenol and nivalenol in Spanish corn-based food products. Journal of Food Composition and Analysis. 21(5):423-427. doi:10.1016/j.jfca.2008.03.009S42342721

Biocleaning of animal glue on wall paintings by Pseudomonas stutzeri

The article focuses on the Biocleaning of indoor wall paintings subjected to animal glue alterations applied in old restorations. The cleaning difficulties by traditional restoratoion methods make biocleaning strategy that uses a viable non-txic bacteria strategy. Presented in this article is the research about the Pseudomonas stutzeri cleaning of animal glue of Santos Juanes church of Valencia, Spain.Bosch Roig, MDP.; Regidor Ros, JL.; Soriano Sancho, MP.; Montes Estellés, RM. (2013). Biocleaning of animal glue on wall paintings by Pseudomonas stutzeri. Chimica Oggi – Chemistry Today. 31(1):50-53. http://hdl.handle.net/10251/56574S505331

High prevalence of Salmonella spp. in wastewater reused for irrigation assessed by molecular methods

[EN] Salmonella spp. is one of the most important causal agents of food-borne illness in developed countries and its presence in irrigation water poses a risk to public health. Its detection in environmental samples is not easy when culture methods are used, and molecular techniques such as PCR or ribosomal rRNA probe hybridization (Fluorescent zn situ Hybridization, FISH) are outstanding alternatives. The aim of this work was to determine the environmental risk due to the presence of Salmonella spp. in wastewater by culture, PCR and FISH. A new specific rDNA probe for Salmonella was designed and its efficiency was compared with the rest of methods Serotype and antibiotic resistance of isolated strains were determined. Forty-five wastewater samples (collected from two secondary wastewater treatment plants) were analysed. Salmonella strains were isolated in 24 wastewater samples (53%), two of them after disinfection treatment. Twenty-three Salmonella strains exhibited resistance to one or more antimicrobial agent. Analysis of wastewater samples yielded PCR positive results for Salmonella in 28 out of the 45 wastewater samples (62%). FISH analysis allowed for the detection of Salmonella in 27 (60%) samples. By using molecular methods, Salmonella was detected in four samples after disinfection treatment. These results show the prevalence of Salmonella in reclaimed wastewater even after U.V. disinfection, what is a matter of public health concern, the high rates of resistance to antibiotics and the adequacy of molecular methods for its rapid detection. FISH method, with SA23 probe developed and assayed in this work provides a tool for detecting Salmonella in water within few hours, with a high rate of effectiveness.Authors gratefully acknowledge the financial support from the Ministerio de Ciencia e Innovacion (Project: AGL2008-05275-C03-02).Santiago Cuellar, P.; Jiménez Belenguer, AI.; García Hernández, J.; Montes Estellés, RM.; Hernández Pérez, M.; Castillo López, MÁ.; Ferrús Pérez, MA.... (2018). High prevalence of Salmonella spp. in wastewater reused for irrigation assessed by molecular methods. International Journal of Hygiene and Environmental Health. 221(1):95-101. https://doi.org/10.1016/j.ijheh.2017.10.007S95101221

Determinación de tricotecenos, zearalenona y zearalenoles en alimentos derivados de maíz del mercado español

[EN] Among the main Spanish commercially available trademarks, we have selected a total of 25 samples of corn-based foods, which have the highest consume rate, to carry out the analysis of deoxynivalenol (DON), T-2 toxin, zearalenone (ZEA) and zearalenols (ZOL). The contents of mycotoxins were determined by gas chromatography with flame ionization detection, and those of ZEA were confirmed by HPLC with fluorescence detection. Of the 25 analyzed samples, the incidence of DON, ZEA and -ZOL was 68, 44 and 24%, respectively; levels detected ranged from 29-195, 34-216, and 36-71 µg/kg, respectively. T-2 toxin was only detected in one sample (< 50 µg/kg). ß-ZOL was not present in excess of the detection limit in the investigated samples. The results suggest a risk for consumers of corn products and the need to monitor the final products before consumption. This is the first report in Spain on natural contamination with these mycotoxins in corn-based foods.[ES] Se han seleccionado 25 muestras de alimentos derivados de maíz entre las principales marcas y las de mayor consumo del mercado español. Éstas se han analizado para detectar la presencia natural de deoxinivalenol (DON), toxina T-2, zearalenona (ZEA) y - y ß-zearalenoles (ZOL). Los contenidos de micotoxinas se han determinado por cromatografía de gases con detector de ionización de llama, confirmando la presencia de zearalenona por cromatografía líquida de alta resolución con detector de fluorescencia. La incidencia de DON, ZEA y -ZOL en las 25 muestras fue del 68, 44 y 24%, respectivamente; los niveles detectados variaron entre 29-195, 34-216, y 36-71 µg/kg, respectivamente. La toxina T-2 sólo se detectó en una de las muestras (< 50 µg/kg). Por último la micotoxina ß-ZOL no fue detectada por encima del límite de detección en ninguna de las muestras analizadas. La presencia de micotoxinas en este tipo de productos supone un riesgo para la salud de los consumidores e indica la necesidad de controlar estos productos finales antes de ser consumidos. Este trabajo constituye el primer estudio sobre la presencia natural de estas micotoxinas en alimentos derivados de maíz presentes en el mercado español.This work as been financed by the Spanish Comisión Interministerial de Ciencia y Tecnología (Project Ref. AGL2001-2974-C05-04) whose support is gratefully acknowledgedCerveró, MC.; Castillo López, M.; Montes Estellés, RM.; Hernandez, E. (2007). Determination of trichothecenes, zearalenone and zearalenols in commercially available corn-based foods in Spain. Revista Iberoamericana de Micología. 24:52-55. http://hdl.handle.net/10251/108044S52552

Biocleaning tests with bacteria on mural paintings

Los microorganismos han sido considerados como agentes causantes de biodeterioro de obras de arte, sin embargo, en la actualidad se empiezan a utilizar para la limpieza de restos de compuestos orgánicos y costras salinas difíciles de eliminar por los métodos tradicionales de restauración. Este trabajo desarrolla el uso de Pseudomonas stutzeri para la ¿biolimpieza¿ de pinturas murales, con la intención de eliminar restos de materia orgánica de antiguas restauraciones o eflorescencias salinas insolubles. Para ello se ensayan distintas cepas de Pseudomonas stutzeri de colecciones tipo y distintos soportes que facilite su aplicación directa sobre obra real. Los métodos obtenidos en las pruebas previas se aplican de manera experimental sobre fragmentos de las pinturas murales de la Iglesia de los Santos Juanes de Valencia.Microorganisms have been considered agents causing biodeterioration of works of art. Nowadays they are however starting to be used for cleaning remains of organic compounds and salt crusts that are difficult to eliminate by traditional restoration methods. This work develops the use of Pseudomonas stutzeri for ¿biocleaning¿ mural paintings, for the purpose of eliminating remains of organic material from old restorations or insoluble saline efflorescence. To this end different strains of Pseudomonas stutzeri are used from type collections and different supports facilitating their direct application on real works. The methods obtained in the preliminary tests are experimentally applied on the mural paintings of Santos Juanes Church in Valencia.Bosch Roig, MDP.; Regidor Ros, JL.; Soriano Sancho, MP.; Domenech Carbo, MT.; Montes Estellés, RM. (2010). Ensayos de biolimpieza con bacterias en pinturas murales. Arché. (4-5):117-124. http://hdl.handle.net/10251/307041171244-