Exposure and risk characterizations of ochratoxins A and aflatoxins through maize (Zea mays) consumed in different agro-ecological zones of Ghana.

Mycotoxin contamination of foodstuffs is a serious food safety concern globally as the prolonged ingestion of these toxins has the tendency to worsen the risk of hepatocellular carcinoma. This study aimed at estimating ochratoxin A (OTA) and aflatoxin (AF) levels above international (European Food Safety Authority, EFSA) and local (Ghana Standards Authority, GSA) standards as well as the health risks associated with the consumption of maize (n = 180) sampled from six (6) regions representing the agro-ecological zones of Ghana. OTA and AF were measured with High-Performance Liquid Chromatography with a Fluorescence detector. Out of the 180 samples analyzed for total aflatoxins (AFtotal), 131/180 tested positive and 127 (70.50%) exceeded the limits of EFSA and ranged 4.27-441.02 µg/kg. While for GSA, 116 (64.44%) of samples exceeded this limit and ranged between 10.18 and 441.02 µg/kg. For OTA, 103/180 tested positive and 94 (52.22%) of samples between the range 4.00-97.51 µg/kg exceeded the tolerable limit of EFSA, whereas 89 (49.44%) and were in the range of 3.30-97.51 µg/kg exceeded the limits of GSA. Risk assessment values for total aflatoxins (AFtotal) ranged between 50 and 1150 ng/kg bw/day, 0.4-6.67, 0-0.0323 aflatoxins ng/kg bw/day and 1.62-37.15 cases/100,000 person/year for Estimated Daily Intake (EDI), Margin of Exposure (MOE), Average Potency, and Cancer Risks respectively. Likewise, ochratoxin (OTA) values were in the ranges of 8.6 × 10-3-450 ng/kg bw/day, 0.05-2059.97, 0-0.0323 ochratoxins ng/kg bw/day and 2.78 × 10-4-14.54 cases/100,000 person/year. Consumption of maize posed adverse health effects in all age categories of the locations studied since the calculated MOE values were less than 10,000.

Potentially toxic element (PTE) levels in maize, soil, and irrigation water and health risks through maize consumption in northern Ningxia, China.

BACKGROUND: Industrial and agricultural activities result in elevated levels of potentially toxic elements (PTEs) in the local environment. PTEs can enter the human body through the food chain and pose severe health risks to inhabitants. In this study, PTE levels in maize, soil, and irrigation water were detected, and health risks through maize consumption were evaluated. METHODS: Maize, soil, and irrigation water samples were collected in northern Ningxia, China. Inductively coupled plasma-optical emission spectrometry was applied to determine the contents of six PTEs. Bioaccumulation factor was used to reflect the transfer potential of a metal from soil to maize. Health risks associated with maize consumption were assessed by deterministic and probabilistic estimation. Sensitivity analysis was performed to determine variables that pose the greatest effect on health risk results. RESULTS: The levels of Pb and Cr in maize exceeded the standards, while the PTE levels in soil and irrigation water did not exceed the corresponding standards. The bioaccumulation factor values of the six PTEs in maize were all lower than 1 and followed the order of Cd > Zn = As > Cr > Cu > Pb. The hazard index (0.0986) was far less than 1 for all inhabitants implying no obvious non-carcinogenic risk. The carcinogenic risk value was 3.261 × 10- 5, which was lower than the maximum acceptable level of 1 × 10- 4 suggested by United States Environmental Protection Agency (USEPA). Females were at greater risk than males, and the age group of below 20 years had the greater risk among all the groups evaluated. Approximately 0.62% of inhabitants exceeded the level for non-carcinogenic risk, while 8.23% exceeded the level for carcinogenic risk. The As concentration and daily intake of maize contributed 35.8, and 29.4% for non-carcinogenic risk results as well as 61.0 and 18.5% for carcinogenic risk results. CONCLUSIONS: Maize was contaminated by Pb and Cr, whereas the associated soil and irrigation water were not contaminated by PTEs. Inhabitants would not suffer obvious harmful health risks through maize consumption. Arsenic level and daily intake of maize were the most sensitive factors that impact health risks.

DP-2Ø2216-6 maize does not adversely affect rats in a 90-day feeding study.

Maize plants containing event DP-2Ø2216-6 (DP202216), which confers herbicide tolerance through expression of phosphinothricin acetyltransferase and enhanced grain yield potential via temporal modulation of the native ZMM28 protein, were developed for commercialization. To address current regulatory expectations, a mandatory 90-day rodent feeding study was conducted to support the safety assessment. Diets containing 50% by weight of ground maize grain from DP202216, non-transgenic control, and 3 non-transgenic reference varieties, were fully characterized, along with the grain, and diets were fed to Crl:CD®(SD) rats for at least 90 days. As anticipated, no biologically-relevant effects or toxicologically-significant differences were observed on survival, body weight/gain, food consumption/efficiency, clinical and neurobehavioral evaluations, ophthalmology, clinical pathology (hematology, coagulation, clinical chemistry, urinalysis), organ weights, or gross and microscopic pathology parameters in rats fed a diet containing up to 50% DP202216 maize grain when compared with rats fed diets containing control or reference maize grains. The results of this study support the conclusion that maize grain from plants containing event DP-2Ø2216-6 is as safe and nutritious as maize grain not containing the event and add to the significant existing database of rodent subchronic studies demonstrating the absence of hazards from consumption of edible fractions of genetically modified plants.

Parallel validation of a green-solvent extraction method and quantitative estimation of multi-mycotoxins in staple cereals using LC-MS/MS.

In this study, 15 different mycotoxins were estimated in three staple cereals from selected agro-ecological regions in Nigeria using a 'novel' green extraction method, pressurized hot water extraction (PHWE) in comparison to a conventional solvent extraction method. Discrimination of the results of PHWE and solvent extraction using principal component analysis (PCA) and orthogonal projection to latent structures discriminate analysis (OPLS-DA) did not yield any differential clustering patterns. All maize samples (n = 16), 32% (n = 38) of sorghum and 35% (n = 37) of millet samples were positive for at least one of the 15 tested mycotoxins. Contamination levels for the cereals were higher in the warm humid rain forest region and gradually decreased towards the hot and arid region in the north of the country. The results demonstrate the applicability of PHWE as a possible alternative extraction method to conventional methods of extraction, which are solvent based.

Phlobaphenes modify pericarp thickness in maize and accumulation of the fumonisin mycotoxins.

Phlobaphenes are insoluble phenolic compounds which are accumulated in a limited number of tissues such as seed pericarp and cob glumes, conferring on them a typical red-brown pigmentation. These secondary metabolites, derived from 3-deoxy flavonoids, are thought to have an important role in plants' resistance against various pathogens, e.g. by reducing fungal infection, and also to have beneficial effects on human and animal health due to their high antioxidant power. The aim of this work was to determine the role of phlobaphenes in reducing mycotoxin contamination on maize kernels. We analysed the effect of the P1 (pericarp color 1) gene on phlobaphenes accumulation, pericarp thickness and fumonisins accumulation. Analysing fumonisins accumulation in different genetic backgrounds through three seasons, we found a clear decrease of these toxins through the three years (Wilcoxon test, Z = 2.2, p = 0.0277) in coloured lines compared with the isogenic non-coloured ones. The coloured lines, carrying P1 allele showed an increase of phlobaphenes (about 10-14 fold) with respect to colourless lines. Furthermore there was a correlation between phlobaphenes accumulation and pericarp thickness (R = 0.9318; p = 0.0067). Taken together, these results suggest that the P1 gene plays a central role in regulating phlobaphenes accumulation in maize kernels, and indirectly, also tackles mycotoxins accumulation. The development and cultivation of corn varieties rich in phlobaphenes could be a powerful tool to reduce the loss of both quality and yield due to mycotoxin contamination, increasing the safety and the quality of the maize product.

Influência da qualidade micotoxicológica e nutricional de híbridos de milho no custo da ração de frangos de corte / Influence of mycotoxicological and nutritional quality of maize hybrids on broiler chickens feed cost

Objetivou-se avaliar as variáveis micotoxicológicas e nutricionais de híbridos de milho com diferentes características que influenciam no custo da ração para frangos de corte. Foram avaliados 26 híbridos de milho geneticamente modificados nas safrinhas de 2016 e 2017, com diferentes germoplasmas, textura de endosperma e duração do ciclo. Nos híbridos, foram avaliados grãos avariados, fumonisinas (B1+B2) (FUM), aflatoxinas (B1+B2+G1+G2) (AFLA), zearalenona (ZEA), deoxinivalenol (DON), umidade, proteína bruta (PB), energia metabolizável aparente corrigida para balanço de nitrogênio (EMAn), aminoácidos digestíveis para aves (lisina, metionina, cistina e treonina) e o respectivo custo da ração inicial para frangos de corte, que foi calculada pelo custo mínimo. A prevalência de FUM, AFLA, ZEA e DON foi de 90, 17, 33 e 0%, com médias de 3067, 1, 38 e 0µg/kg nos dois anos, respectivamente. A média de EMAn e PB foi de 3264kcal/kg e 8,02%, respectivamente, e diferiu (P<0,05) nos dois anos. O custo da ração foi influenciado significativamente (P<0,05) por FUM, PB, EMAn nos dois anos. Híbridos com tecnologia Viptera apresentam menor concentração por FUM e menor custo da ração. Híbridos de ciclo precoce têm menor concentração de FUM, maiores percentuais de PB e de aminoácidos digestíveis e menor custo da ração.(AU)

The objective of this study was to evaluate the mycotoxicological and nutritional variables of maize hybrids with different characteristics that influence the broiler chicken's feed costs. In 2016 and 2017 winter crops, 26 genetically modified hybrids of maize with different germplasm, endosperm texture and cycle duration were evaluated. The analyzed variables were damaged grains, fumonisins (B 1 +B 2 ) (FUM), aflatoxins (B 1 +B 2 +G 1 +G 2 ) (AFLA), zearalenone (ZEA), deoxynivalenol (DON), moisture, crude protein (CP), apparent metabolizable energy corrected for nitrogen balance (AMEn), digestible amino acids for poultry (lysine, methionine, cystine and threonine) and the respective cost of the initial feed for broiler chickens calculated at the minimum cost. The prevalence of FUM, AFLA, ZEA and DON was 90, 17, 33 and 0%, with means of 3067, 1, 38 and 0µg/kg in the two years, respectively. The mean of AMEn and CP was 3264kcal/kg and 8.02%, respectively, and differed (P< 0.05) in the two years. The feed cost was significantly influenced (P<0.05) by FUM, PB, AMEn in two years. Hybrids with Viptera technology show lower concentration per FUM and lower feed cost. Early cycle hybrids have lower concentrations of FUM, higher percentages of CP and digestible amino acids, and lower feed costs.(AU)

Maize (Zea mays L.) root exudates modify the surface chemistry of CuO nanoparticles: Altered aggregation, dissolution and toxicity.

Copper oxide nanoparticles (CuO NPs), as an antimicrobial nanomaterial, have found many applications in agriculture. Ubiquitous and complex root exudates (RE) in the plant root zone motivates the determination of how specific components of RE interact with CuO NPs. This work aims to reveal the role of maize (Zea mays L.)-derived RE and their components on the aggregation and dissolution of CuO NPs in the rhizosphere. We observed that RE significantly inhibited the aggregation of CuO NPs regardless of ionic strength and electrolyte type. In the presence of RE, the CCC of CuO NPs in NaCl shifted from 30 to 125 mM and the value in CaCl2 shifted from 4 to 20 mM. Furthermore, this inhibition was correlated with molecular weight (MW) of RE fractions. Higher MW fraction (>10 kDa) reduced the aggregation most. We also discovered that RE significantly promoted the dissolution of CuO NPs and lower MW fraction (<3 kDa) RE mainly contributed to this process. Additionally, phytotoxicity of CuO NPs in the presence of RE and different fractions of RE was evaluated. The addition of 20 mg/L RE reduced the seedlings growth rate to 1.89% after 7 days exposure to 25 mg/L CuO NPs, which were significantly lower than the control group (4.82%). Notably, Cu accumulation in plant root tissues was significantly enhanced by 20 mg/L RE. This study provides useful insights into the interactions between RE and CuO NPs, which is of significance for the safe use of CuO NPs-based antimicrobial products in agricultural production.

Bacillus thuringiensis Maize Expressing a Fusion Gene Cry1Ab/Cry1AcZM Does Not Harm Valued Pollen Feeders.

The ladybird Propylea japonica, adults of the green lacewing Chrysoperla nipponensis and the honey bee Apis mellifera are common pollen feeders in many crop systems. They could therefore be directly exposed to Cry proteins in Bacillus thuringiensis (Bt)-transgenic crop fields by ingestion of pollen. They, or closely related species, are therefore often selected as surrogate test species in non-target risk assessment of Bt plants. In the current study, we evaluated the potential effects of the ingestion of Bt maize pollen containing the Cry1Ab/Cry1Ac fusion protein on various life-table parameters of the three pollen-feeding non-target species in laboratory feeding assays. The results showed that pupation rate and male adult fresh weight of P. japonica were significantly increased when fed pollen from Bt maize compared to control maize pollen, but other test life-table parameters were not affected. For the other two species, none of the tested life-table parameters (survival, pre-oviposition period, fecundity and adult fresh weight for C. nipponensis; survival and mean acinus diameter of hypopharyngeal glands for A. mellifera) differed between non-Bt and Bt maize pollen treatments. ELISA measurements confirmed the stability and uptake of the Cry protein by all three species during the feeding bioassays. In addition, a sensitive insect bioassay confirmed the bioactivity of the Cry1Ab/Cry1Ac protein in the Bt maize pollen used. Overall, the results suggested that the three pollen feeders are not sensitive to the Cry1Ab/Cry1Ac protein, and planting of the Bt maize variety will pose a negligible risk to P. japonica, adult C. nipponensis and adult A. mellifera.

Toxicidad oral aguda de los extractos etanólicos de Eucalyptus globulus, Morinda citrifolia, Peperomia glauca, Schinus molle y Zea mays en ratones BALB/c 53 / Acute oral toxicity of Eucalyptus globulus, Morinda citrifolia, Peperomia glauca, Schinus molle and Zea mays ethanolic extracts on BALB/c 53 mice

Objetivo. Evaluar la toxicidad aguda de los extractos etanólicos del Eucalyptus globulus Labill. (eucalipto), Morinda citrifolia L. (noni), Peperomia glauca (pino) (congona), Schinus molle L. (molle) y Zea mays L. (Maíz morado) en ratones Balb/c 53. Materiales y métodos. Se utilizaron 60 ratones machos divididos en seis grupos (eucalipto, noni, congona, molle, maíz morado y control). Los grupos tratados recibieron por vía oral una dosis única de 2000 mg/kg de los extractos etanólicos, y el grupo control recibió polisorbato 2 mL/kg al 3%. Se evaluó ganancia de peso, valores hematológicos (hematocrito, eritrocitos, hemograma, leucocitos, plaquetas), bioquímica sérica (úrea, creatinina, ALT, proteínas totales, albumina, globulinas), histopatología hepática y renal. Resultados. Se observó signos de inquietud, excitación y aparente fotosensibilidad en el grupo eucalipto, por una hora. Se encontró leucopenia en grupos congona, molle, eucalipto y maíz morado; trombocitopenia en grupos eucalipto y molle, y elevación del ALT en los grupos congona y eucalipto, en comparación con los valores del grupo control. La ganancia de peso, los demás valores hematológicos, así como la bioquímica renal y hepática en los otros grupos no fueron significativos. Conclusiones. En las condiciones experimentales no se observó signos de toxicidad ni mortalidad en el ensayo; la DL50 de los extractos etanólicos estaría sobre los 2000 mg/kg.

Objective. This study was performed to evaluate the acute toxicity of ethanolic extracts of Eucalyptus globulus Labill. (Eucalipto), Morinda citrifolia L. (noni), Peperomia glauca (pino) (Congona), Schinus molle L. (molle) y Zea mays L. (maíz morado) in Balb/c mice. Materials and methods. Sixty male mice were divided into 6 groups (Eucalipto, Noni, Congona, Molle, Maíz morado and Control) of 10 each were used. The guide for the Organization for Economic Cooperation and Development (OECD 423) was followed for the study. The treated group received for gavage a single dose at 2000 mg/kg and the control group received polysorbate at 2 mL/kg at 3%. Weight gain, hematological values (hematocrit, erythrocytes, hemogram, leukocytes, platelets), serum biochemistry (urea, creatinine, ALT, total proteins, albumin, globulins), hepatic and renal histopathology were performed. Results. No signs of mortality and morbidity were observed as a consequence of the administration of the extracts, except for the Eucalipto group, which presented restlessness, excitation and apparent photosensitivity for one hour. There was leukopenia in Congona, Molle, Eucalipto and Maíz morado groups; thrombocytopenia in groups Eucalipto and Molle; and elevations of ALT in Congona and Eucalipto groups in comparison than the values from control group. Weight gain and other hematological values, as well as renal and hepatic biochemistry in the other groups were not significant. Conclusions. Under experimental conditions no signs of toxicity or mortality were observed in the trial; the LD50 of the ethanolic extracts would be above 2000 mg/kg.

Effect of genetically modified corn on the jejunal mucosa of adult male albino rat.

Genetically modified (GM) plants expressing insecticidal traits offer a new strategy for crop protection. GM-corn contains Bacillus thuringiensis (Bt) genes producing delta endotoxins in the whole plant. Diet can influence the characteristics of the gastrointestinal tract altering its function and structure. The aim of this study was to evaluate the effect of GM-corn on the histological structure of jejunal mucosa of adult male albino rat using different histological, immunohistochemical and morphometrical methods. Twenty adult male albino rats were divided into two equal groups; control and GM-corn fed group administered with 30% GM-corn for 90days. Specimens from the jejunum were processed for light and electron microscopy. Immunohistochemical study was carried out using antibody against proliferating cell nuclear antigen (PCNA). Different morphometrical parameters were assessed. Specimens from GM-corn fed group showed different forms of structural changes. Focal destruction and loss of the villi leaving denuded mucosal surface alternating with stratified areas were observed, while some crypts appeared totally disrupted. Congested blood capillaries and focal infiltration with mononuclear cells were detected. Significant upregulation of PCNA expression, increase in number of goblet cells and a significant increase in both villous height and crypt depth were detected. Marked ultrastructural changes of some enterocytes with focal loss of the microvillous border were observed. Some enterocytes had vacuolated cytoplasm, swollen mitochondria with disrupted cristae and dilated rough endoplasmic reticulum (rER). Some cells had dark irregular nuclei with abnormally clumped chromatin. It could be concluded that consumption of GM-corn profoundly alters the jejunal histological structure.

Ecological risk assessment for DvSnf7 RNA: A plant-incorporated protectant with targeted activity against western corn rootworm.

MON 87411 maize, which expresses DvSnf7 RNA, was developed to provide an additional mode of action to confer protection against corn rootworm (Diabrotica spp.). A critical step in the registration of a genetically engineered crop with an insecticidal trait is performing an ecological risk assessment to evaluate the potential for adverse ecological effects. For MON 87411, an assessment plan was developed that met specific protection goals by characterizing the routes and levels of exposure, and testing representative functional taxa that would be directly or indirectly exposed in the environment. The potential for toxicity of DvSnf7 RNA was evaluated with a harmonized battery of non-target organisms (NTOs) that included invertebrate predators, parasitoids, pollinators, soil biota as well as aquatic and terrestrial vertebrate species. Laboratory tests evaluated ecologically relevant endpoints such as survival, growth, development, and reproduction and were of sufficient duration to assess the potential for adverse effects. No adverse effects were observed with any species tested at, or above, the maximum expected environmental concentration (MEEC). All margins of exposure for NTOs were >10-fold the MEEC. Therefore, it is reasonable to conclude that exposure to DvSnf7 RNA, both directly and indirectly, is safe for NTOs at the expected field exposure levels.

Safety assessment of dicamba mono-oxygenases that confer dicamba tolerance to various crops.

Dicamba tolerant (DT) soybean, cotton and maize were developed through constitutive expression of dicamba mono-oxygenase (DMO) in chloroplasts. DMO expressed in three DT crops exhibit 91.6-97.1% amino acid sequence identity to wild type DMO. All DMO forms maintain the characteristics of Rieske oxygenases that have a history of safe use. Additionally, they are all functionally similar in vivo since the three DT crops are all tolerant to dicamba treatment. None of these DMO sequences were found to have similarity to any known allergens or toxins. Herein, to further understand the safety of these DMO variants, a weight of evidence approach was employed. Each purified DMO protein was found to be completely deactivated in vitro by heating at temperatures 55 °C and above, and all were completely digested within 30 s or 5 min by pepsin and pancreatin, respectively. Mice orally dosed with each of these DMO proteins showed no adverse effects as evidenced by analysis of body weight gain, food consumption and clinical observations. Therefore, the weight of evidence from all these protein safety studies support the conclusion that the various forms of DMO proteins introduced into DT soybean, cotton and maize are safe for food and feed consumption, and the small amino acid sequence differences outside the active site of DMO do not raise any additional safety concerns.

Corn rootworm-active RNA DvSnf7: Repeat dose oral toxicology assessment in support of human and mammalian safety.

Genetically modified (GM) crops have been developed and commercialized that utilize double stranded RNAs (dsRNA) to suppress a target gene(s), producing virus resistance, nutritional and quality traits. MON 87411 is a GM maize variety that leverages dsRNAs to selectively control corn rootworm through production of a 240 base pair (bp) dsRNA fragment targeting for suppression the western corn rootworm (Diabrotica virgifera virgifera) Snf7 gene (DvSnf7). A bioinformatics assessment found that endogenous corn small RNAs matched ∼450 to 2300 unique RNA transcripts that likely code for proteins in rat, mouse, and human, demonstrating safe dsRNA consumption by mammals. Mice were administered DvSnf7 RNA (968 nucleotides, including the 240 bp DvSnf7 dsRNA) at 1, 10, or 100 mg/kg by oral gavage in a 28-day repeat dose toxicity study. No treatment-related effects were observed in body weights, food consumption, clinical observations, clinical chemistry, hematology, gross pathology, or histopathology endpoints. Therefore, the No Observed Adverse Effect Level (NOAEL) for DvSnf7 RNA was 100 mg/kg, the highest dose tested. These results demonstrate that dsRNA for insect control does not produce adverse health effects in mammals at oral doses millions to billions of times higher than anticipated human exposures and therefore poses negligible risk to mammals.

Toxicological evaluation of the flavonoid-rich extract from Maydis stigma: Subchronic toxicity and genotoxicity studies in mice.

ETHNOPHARMACOLOGICAL RELEVANCE: Maydis stigma (corn silk) has a long history of use as a traditional herbal medicine or functional food in China and many other countries and has been listed in the Chinese Pharmacopea. However, little data about its potential toxicity is available. AIM OF THE STUDY: In this study, we evaluated the subchronic toxicity and genotoxicity of the flavonoid-rich extract from Maydis stigma (FMS) in mice. MATERIALS AND METHODS: In the subchronic toxicity study, the FMS was administered orally to mice at doses of 2.50, 5.00 and 10.00g/kg/day for 28 consecutive days. At the end of experiment, general clinical signs, mortality, haematological, biochemical and histopathological parameters were examined. The genotoxicity of FMS was also evaluated by the micronucleus assay and the sperm malformation assay. RESULTS: All animals survived until the scheduled necropsy, and no statistically significant or toxicologically relevant differences were observed in any of the FMS-treatment groups, compared with the control group. The no-observed-adverse-effect level (NOAEL) was determined as 10.00g/kg/day. Based on the results of the micronucleus assay and the sperm malformation assay, no evidence of genotoxicity was found either in somatic cells or germ cells even at an experimental upper limit dose (10.00g/kg/day). CONCLUSIONS: The results of the present studies might support the safe use of FMS as a functional food, food additive and natural remedy.

Estudio de los parámetros que afectan al contenido de deoxinivalenol en cereales o alimentos a base de cereales obtenidos en comercios de Valencia (España) / Study of several parameters affecting the deoxynivalenol content in cereal and cereal-based products from Valencia (Spain)

Las micotoxinas son metabolitos fúngicos que aparecen comúnmente como contaminantes de muchos cereales y pueden causar una amplia variedad de efectos tóxicos. En el presente estudio, se analizó un total de 182 muestras de diferentes cereales (arroz, trigo, maíz, avena, espelta, soja y tapioca) obtenidos en establecimientos de la Comunidad Valenciana (España). Se examina la presencia de deoxinivalenol (DON) y se realiza un estudio estadístico de las muestras según el tipo de cultivo (orgánico o convencional), su composición, el tipo de producto y la marca (comercial o blanca) para estimar si estos parámetros influyen en la concentración de DON. Del total de muestras, 111 estaban contaminadas con DON, pero en concentraciones inferiores a los límites permitidos por la legislación europea. Se observó mayor incidencia de DON en muestras de trigo (80%) seguidas de maíz (35%) y arroz (13%), pero sin diferencia significativa (p>0,05) entre el tipo de cereal; ni con la práctica agrícola. Sin embargo, los resultados demostraron que el tipo de producto en el cereal procesado (p<0,001; los productos a base de lluvia y sémola presentaran valores mayores de DON que los fideos), los componentes del alimento procesado (p<0,01; los niveles de DON eran superiores en las rosquilletas de pan simples respecto a las rosquilletas con queso y con chocolate ) y la marca (p<0,05; las marcas blancas contienen más DON que las comerciales) si influyen en los niveles de DON hallados en las muestras de trigo (AU)

Mycotoxins are fungal metabolites that commonly appear as contaminants in many cereals and can cause a variety of toxic effects. In this study, a total of 182 samples of different cereals (rice, wheat, corn, oats, spelt, soy and tapioca) obtained in establishments of Valencia (Spain) were analyzed. The presence of deoxynivalenol (DON) was determined and a statistical study of the samples was performed according to the type of crop (organic or conventional), its composition, the type of product and brand (commercial or white) to estimate whether these parameters influence DON concentration. Of the total samples, 111 were contaminated with DON, but their concentration were below the limits allowed by European legislation. Higher DON concentration was observed in wheat samples (80%) followed by corn (35%) and rice (13%), but no significant difference (p> 0.05) between the type of cereal; or harvest conditions. However, the results showed that the type of product in the processing cereal (p <0.001; the rain-based products and grits presented higher values of DON than noodles), processed food components (p <0.01; DON levels were higher in simple snacks than snacks bread with cheese and chocolate) and brand (p <0.05; white brands contain more DON than commercial ones) have related to DON concentration found in wheat samples (AU)

Chronic Responses of Daphnia magna Under Dietary Exposure to Leaves of a Transgenic (Event MON810) Bt-Maize Hybrid and its Conventional Near-Isoline.

Insect resistance is the second most common trait globally in cultivated genetically modified (GM) plants. Resistance is usually obtained by introducing into the plant's genome genes from the bacterium Bacillus thuringiensis (Bt) coding for insecticidal proteins (Cry proteins or toxins) that target insect pests. The aim of this study was to examine the hypothesis that a chronic, high-dose dietary exposure to leaves of a Bt-maize hybrid (GM event MON810, expressing a transgenic or recombinant Cry1Ab toxin), exerted no adverse effects on fitness parameters of the aquatic nontarget organism Daphnia magna (water flea) when compared to an identical control diet based on leaves of the non-GM near-isoline. Cry1Ab was immunologically detected and quantified in GM maize leaf material used for Daphnia feed. A 69-kD protein near Bt's active core-toxin size and a 34-kD protein were identified. The D. magna bioassay showed a resource allocation to production of resting eggs and early fecundity in D. magna fed GM maize, with adverse effects for body size and fecundity later in life. This is the first study to examine GM-plant leaf material in the D. magna model, and provides of negative fitness effects of a MON810 maize hybrid in a nontarget model organism under chronic, high dietary exposure. Based upon these results, it is postulated that the observed transgenic proteins exert a nontarget effect in D. magna and/or unintended changes were produced in the maize genome/metabolome by the transformation process, producing a nutritional difference between GM-maize and non-GM near-isoline.

Neonicotinoid-Coated Zea mays Seeds Indirectly Affect Honeybee Performance and Pathogen Susceptibility in Field Trials.

Thirty-two honeybee (Apis mellifera) colonies were studied in order to detect and measure potential in vivo effects of neonicotinoid pesticides used in cornfields (Zea mays spp) on honeybee health. Honeybee colonies were randomly split on four different agricultural cornfield areas located near Quebec City, Canada. Two locations contained cornfields treated with a seed-coated systemic neonicotinoid insecticide while the two others were organic cornfields used as control treatments. Hives were extensively monitored for their performance and health traits over a period of two years. Honeybee viruses (brood queen cell virus BQCV, deformed wing virus DWV, and Israeli acute paralysis virus IAPV) and the brain specific expression of a biomarker of host physiological stress, the Acetylcholinesterase gene AChE, were investigated using RT-qPCR. Liquid chromatography-mass spectrometry (LC-MS) was performed to detect pesticide residues in adult bees, honey, pollen, and corn flowers collected from the studied hives in each location. In addition, general hive conditions were assessed by monitoring colony weight and brood development. Neonicotinoids were only identified in corn flowers at low concentrations. However, honeybee colonies located in neonicotinoid treated cornfields expressed significantly higher pathogen infection than those located in untreated cornfields. AChE levels showed elevated levels among honeybees that collected corn pollen from treated fields. Positive correlations were recorded between pathogens and the treated locations. Our data suggests that neonicotinoids indirectly weaken honeybee health by inducing physiological stress and increasing pathogen loads.

Ganho de peso, consumo de ração e histologia de órgãos de leitões alimentados com rações contendo baixos níveis de fumonisina B1 / Weight gain, feed consumption and histology of organs from piglets fed rations containing low levels of fumonisin B1

A fumonisina B1 (FB1) é um metabólito secundário produzido principalmente por Fusarium verticilioides em diversos tipos de alimentos, principalmente o milho, o qual constitui a base para composição de rações para várias espécies de animais domésticos. A FB1é particularmente tóxica para suínos, cujas manifestações clínicas são evidentes em animais expostos a altas concentrações de FB1 na ração (em geral, acima de 30mg/kg). No entanto, são escassos os estudos sobre os efeitos da FB1em suínos alimentados com rações contendo baixas concentrações de fumonisinas, as quais são mais prováveis de serem encontradas em condições de campo. O objetivo do estudo foi avaliar os efeitos da exposição de leitões a baixos níveis de FB1 na ração, durante 28 dias, sobre o ganho de peso, consumo de ração, peso relativo de órgãos e aspectos histológicos do baço, fígado, pulmões, rins e coração. Vinte e quatro leitões foram distribuídos em 4 grupos experimentais e alimentados com rações contendo 0mg (controle), 3,0mg, 6,0mg ou 9,0mg FB1/kg de ração. As diferentes dietas não afetaram (P>0,05) o ganho de peso e nem o peso relativo dos órgãos analisados. Não foram constatadas lesões macroscópicas ou histopatológicas no baço, fígado, rins e coração. No entanto, foram observadas lesões histopatológicas nos pulmões de todos os suínos alimentados com rações contaminadas com fumonisinas, indicando que nenhum dos níveis de FB1 usados no experimento poderia ser considerado como seguro para suínos. São necessários novos estudos sobre os mecanismos de ação tóxica da FB1 em suínos, sobretudo em condições de exposição prolongada a baixos níveis de contaminação na ração.

Fumonisin B1 (FB1) is a secondary metabolite produced mainly by Fusarium verticilioides in several types of foods, particularly corn, which is the basis for composition of feed for several domestic animals. FB1 is particularly toxic to pigs, being the clinical manifestations evident in animals exposed to high concentrations of FB1 in the diet (generally above 30mg/kg). However, there are few studies on the effects of FB1 on pigs fed rations containing low concentrations of fumonisin, which are most probably found under field conditions. The aim of the study was to evaluate the effects of a 28-day exposure of piglets to low levels of FB1 in the feed on the weight gain, feed consumption, organ weights and histological aspects of the spleen, liver, lungs, kidneys and heart. Twenty-four pigs were assigned into 4 experimental groups and fed diets containing 0mg (control), 3.0mg, 6.0mg or 9.0mg FB1/kg diet. The different diets did not affect (P>0.05) the weight gain or the weight of organs examined. There were no macroscopic or histological lesions in the spleen, liver, kidneys and heart. However, histological lesions were found in the lungs from all animals fed rations containing fumonisin, hence indicating that none of the FB1 levels used in the experiment could be considered as safe for piglets. Further studies on the mechanisms of toxic action of FB1 in pigs are needed, particularly under conditions of prolonged exposure to low contamination levels in the diet.

An aptamer-based dipstick assay for the rapid and simple detection of aflatoxin B1.

A rapid and simple dipstick assay based on an aptamer has been developed for the determination of aflatoxin B1 (AFB1). The dipstick assay format was based on a competitive reaction of the biotin-modified aptamer specific to AFB1 between target and cy5-modified DNA probes. Streptavidin and anti-cy5 antibody as capture reagents were immobilized at test and control lines on a membrane of the dipstick assay. After optimization, the limit of detection for the dipstick assay was 0.1 ng/ml AFB1 in buffer. The method was confirmed to be specific to AFB1, and the entire process of the assay can be completed within 30 min. Aqueous methanol (20%) provided a good extraction efficiency, and the matrix influence from corn extracts was successfully reduced through 2-fold dilution. The results of AFB1 analysis for corn samples spiked with known concentration of AFB1 by the dipstick assay and ELISA showed good agreement. The cut-off value of the dipstick assay for corn samples was 0.3 ng/g AFB1. Therefore, the dipstick assay is first reported and considered as a rapid, simple, on-site and inexpensive screening tool for AFB1 determination in grains as well as a corn.