OTA Concentration Research Articles

Construction of dual-signal output sensing platform for different scene of rapid and sensitive ochratoxin A detection in corn

Photoelectrochemical (PEC) is a highly sensitive and fast analytical method that can be used at low concentrations, while photoelectrochromic is a simple and low-cost method primarily utilized for high concentration detection. Therefore, we have developed a dual-signal output sensing platform based on both PEC and photoelectrochromism for rapid and sensitive OTA detection. The sensing platform is divided into signal generation (SG) region and signal output (SO) region, which modified with WO3/BiVO4 photoactive nanocomposites and polyaniline (PANI), respectively. By irradiating the SG region, photogenerated electrons are generated and injected into the SO region through the conductive pathway, resulting in a decrease in surface blue polyaniline and a change to green. The smart device can accurately measure the RGB-Green values, enabling the construction of a photochromic visual sensing platform. After immobilizing the OTA aptamer in the SG region, a linear correlation was observed between the concentration of OTA and the RGB-Green value within the range of 20 ng/L ∼250 μg/L. The detection limit was determined to be 8.33 ng/L (S/N = 3). Furthermore, for a more sensitive OTA detection, a PEC sensing platform was developed utilizing the SG region as a photoanode, exhibiting a linear correlation in the range of 2 pg/L∼300 μg/L with a detection limit of 0.8 pg/L (S/N = 3). The detection of these two modes under the requirement of the international standard for the maximum limit realizes the sensitive OTA detection. The RGB-Green is verified to PEC signal, which improves the detection accuracy. The sensing platform has several advantages and is suitable for various application scenarios.

Mycotoxin detection in selected medicinal plants using chromatographic techniques.

Mycotoxins are toxic mycological products that when consumed, absorbed or inhaled cause sickness or even the death of humans. Therefore, the present study aimed to evaluate the contamination levels of mycotoxins (aflatoxins, AFB1 , AFB2 , AFG1 , AFG2 , and ochratoxin A, OTA) in selected medicinal herbs and shrubs using thin-layer chromatography (TLC) and high-performance liquid chromatography (HPLC). A total of 15 samples of medicinal herbs and shrubs were selected. Among them, four samples were aflatoxin contaminated while two samples were ochratoxin A contaminated. The highest level of aflatoxin was detected in Justicia adhathoda (4,704.94 ppb) through HPLC (153.4ppb) and through TLC, while the lowest level of aflatoxin was detected in Pegnum harmala (205.1ppb) through HPLC. Similarly, the highest level of OTA was detected in Dodonia viscosa (0.53 ppb) through HPLC (0.5ppb) and through TLC, while the lowest level was detected in J. adhathoda (O.11 ppb) through HPLC (0.4ppb) and through TLC. The OTA concentration was very low, being negligible and below permissible limits. The present study concludes that there is a potential risk for the consumption of herbal decoctions. Therefore, regular monitoring and proper management of mycotoxins, including aflatoxins and OTA, in herbal medicines are needed to ensure the safety of herbal drugs to protect consumers.

A Predictive Assessment of Ochratoxin A’s Effects on Oxidative Stress Parameters and the Fermentation Ability of Yeasts Using Neural Networks

The aim of this paper was to examine the effect of different OTA concentrations on the parameters of oxidative stress (glutathione (GSH) and malondialdehyde (MDA) concentrations) and glucose utilization in ethanol production by wine yeasts. In addition to the above, artificial neural networks (ANN) were used to predict the effects of different OTA concentrations on the fermentation ability of yeasts and oxidative stress parameters. The obtained results indicate a negative influence of OTA (4 µg mL−1) on ethanol production after 12 h. For example, K. marxianus produced 1.320 mg mL−1 of ethanol, while in the control sample 1.603 µg mL−1 of ethanol was detected. However, after 24 h, OTA had no negative effect on ethanol production, since it was higher (7.490 and 3.845 mg mL−1) in comparison to control samples. Even low concentrations of OTA affect GSH concentrations, with the highest being detected after 12 and 24 h (up to 16.54 µM), while MDA concentrations are affected by higher OTA concentrations, with the highest being detected at 24 h (1.19 µM). The obtained results with the use of ANNs showed their potential for quantification purposes based on experimental data, while the results of ANN prediction models have shown to be useful for predictions of what outcomes different concentrations of OTA that were not part of experiment will have on the fermentation capacity and oxidative stress parameters of yeasts.

A DNA tetrahedral scaffolds-based electrochemical biosensor for simultaneous detection of AFB1 and OTA

Herein, a bifunctional electrochemical biosensor based on the DNA tetrahedral scaffolds (TDNs) was proposed, OTA@TDNs and AFB1@TDNs were adopted for electrochemical signal output in response to OTA and AFB1 concentration, simultaneously. In order to increase the conductivity of the biosensor, highly porous gold (HPG) was loaded on electrode surface by pulse electrodeposition. Under optimal conditions, the PFc displayed a linear range with AFB1 concentration between 0.05 ∼ 360 ng·mL−1 with the LOD of 3.5 pg·mL−1. And the PMB selective and sensitive responses to OTA are achieved with a linear range of 0.05 ∼ 420 ng·mL−1 and a LOD of 2.4 pg·mL−1. This biosensor has high sensitivity, selectivity and stability for OTA and AFB1 detection in peanut samples. The approach streamlines the experimental procedure, leading to significantly improve the detection efficiency of mycotoxins. Collectively, this method suggest a novel approach for the detection and monitoring of OTA and AFB1 in food sample.

An Aptamer-Based Lateral Flow Biosensor for Low-Cost, Rapid and Instrument-Free Detection of Ochratoxin A in Food Samples.

In this work, a simple and cost-efficient aptasensor strip is developed for the rapid detection of OTA in food samples. The biosensor is based on the lateral flow assay concept using an OTA-specific aptamer for biorecognition of the target analyte. The strip consists of a sample pad, a conjugate pad, a nitrocellulose membrane (NC) and an absorbent pad. The conjugate pad is loaded with the OTA-specific aptamer conjugated with gold nanoparticles (AuNPs). The test line of the NC membrane is loaded with a specific OTA-aptamer probe and the control line is loaded with a control probe. The assay is based on a competitive format, where the OTA present in the sample combines with the OTA aptamer-AuNP conjugate and prevents the interaction between the specific probe immobilized on the test line and the OTA aptamer-AuNP conjugates; therefore, the color intensity of the test line decreases as the concentration of OTA in the sample increases. Qualitative detection of OTA is performed visually, while quantification is performed by reflectance colorimetry using a commercial scanner and image analysis. All the parameters of the assay are investigated in detail and the analytical features are established. The visual limit of detection (LOD) of the strip is 0.05 ng mL-1, while the LOD for semi-quantitative detection using reflectance colorimetry is 0.02 ng mL-1. The lateral flow strip aptasensor is applied to the detection of OTA in wine, beer, apple juice and milk samples with recoveries in the range from 91 to 114%. The assay exhibits a satisfactory selectivity for OTA with respect to other mycotoxins and lasts 20 min. Therefore, the lateral flow strip aptasensor could be useful for the rapid, low-cost and fit-for-purpose on-site detection of OTA in food samples.

Yeasts as sustainable biocontrol agents against ochratoxigenic Aspergillus species and in vitro optimization of ochratoxin A detoxification.

The aims of this study were to evaluate the potential of Hanseniaspora opuntiae, Meyerozyma caribbica, and Kluyveromyces marxianus for in vitro biocontrol of Aspergillus ochraceus, A. westerdijkiae, and A. carbonarius growth, the ochratoxin A (OTA) effect on yeast growth, and yeast in vitro OTA detoxification ability using an experimental design to predict the combined effects of inoculum size, incubation time, and OTA concentration. Predictive models were developed using an incomplete Box-Behnken experimental design to predict the combined effects of inoculum size, incubation time, and OTA concentration on OTA detoxification by the yeasts. The yeasts were able to inhibit fungal growth from 13% to 86%. Kluyveromyces marxianus was the most efficient in inhibiting the three Aspergillus species. Furthermore, high OTA levels (100 ng ml-1) did not affect yeast growth over 72 h incubation. The models showed that the maximum OTA detoxification under optimum conditions was 86.8% (H. opuntiae), 79.3% (M. caribbica), and 73.7% (K. marxianus), with no significant difference (P>0.05) between the values predicted and the results obtained experimentally. The yeasts showed potential for biocontrol of ochratoxigenic fungi and OTA detoxification, and the models developed are important tools for predicting the best conditions for the application of these yeasts as detoxification agents.

Toxicokinetics of a Single Oral Dose of OTA on Dezhou Male Donkeys.

Ochratoxin (OTA) is widely present in a wide range of foods and feeds, causing adverse effects on animals and humans. This study aims to explore the toxicokinetics of OTA-contaminated materials on the Dezhou male donkey. Donkeys received a single orally dose of 2500 μg OTA/kg BW, obtained from Aspergillus ochraceus culture material. The concentrations of OTA in plasma collected at 0, 5, 10, 15, 20, 30, 45 min, and at 1, 1.5, 2, 3, 6, 9, 12, 24, 48, 72, 96 and 120 h were detected by HPLC. OTA eliminated in urine and feces were quantified at 6-h intervals up to 24 h and then at 4-h intervals up to 120 h. The results suggested that the maximum concentration of OTA in plasma was observed at 12 h after administration, with a mean value of 10.34 μg/mL. The total excretion in both urine and feces was about 10% of the intake until 120 h.

An aptamer-assisted biological nanopore biosensor for ultra-sensitive detection of ochratoxin A with a portable single-molecule measuring instrument

Biological nanopore-based single-molecule detection technology has shown ultrahigh sensitivity to various target analyte. But the detection scope of interesting targets is limited due to the lack of effective signal conversion strategies. In addition, conventional nanopore detection instruments are cumbersome, resulting nanopore detection can only be performed in laboratory. Herein, a customizable nanopore current amplifier is constructed to lower the cost and increase the portability of the nanopore instrument, and then an immobilized aptamer-based signal conversion strategy is proposed for α-hemolysin (α-HL) nanopore to detect small molecules (ochratoxin A, OTA). The presence of OTA in sample would trigger the release of probe single-strand DNA (ssDNA) from magnetic beads, which could subsequently cause current blockage in nanopore. The results show that the signal frequency of probe ssDNA has a linear relationship with the OTA concentration in the range of 2 × 101～2 × 103 pmol/L. Compared to other methods, our sensing system has achieved an ultra-sensitive detection of OTA with the detection limit as low as 1.697 pmol/L. This strategy could broaden the scope of nanopore detection and have the potential for rapid and in-situ detection of other food contaminants in the future.

Combination of zinc and selenium alleviates ochratoxin A-induced fibrosis via blocking ROS-dependent autophagy in HK-2 cells

BackgroundOchratoxin A (OTA) is a mycotoxin produced by Aspergillus and Penicillium. The key target organ of OTA toxicity is the kidney, which has a significant impact on human health. Recently, nutrition regulation is suggested to be an effective protection against mycotoxins contamination. The current study investigated the combined protective effects of zinc and selenomethionine (SeMet) (a major component of organic selenium) on OTA-induced renal fibrosis and their potential mechanisms in human renal proximal tubule epithelial cells (HK-2 cells). MethodsCytotoxicity of different concentrations of OTA, zinc and SeMet on HK-2 cells was detected by cell viability, lactate dehydrogenase (LDH) and apoptotic nuclei assays. The expression of fibrosis biomarkers was detected by Real-Time PCR, western blotting and indirect immunofluorescence assays. The production of reactive oxygen species (ROS) was detected by ROS assay kit. The protein expression of autophagy biomarkers was detected by western blotting assay. ResultsCytotoxicity was induced by OTA treatment in a dose-dependent manner, and it was attenuated by zinc or SeMet application in HK-2 cells. Zinc or SeMet application also down-regulated the expression of fibrosis biomarkers, and the combination of them displayed better effects. In addition, OTA increased intracellular ROS level and activated autophagy in a dose-dependent manner, and it was reversed by zinc and SeMet combined application. With the treatment of hydrogen peroxide (H2O2) or rapamycin (the specific activator of autophagy), the combined protective effects of zinc and SeMet were abolished. ConclusionsZinc and SeMet application alleviated OTA-induced cytotoxicity and fibrosis in HK-2 cells. Combination of them was more effective than its individual application. The present study manifest novel insight about the alleviation of OTA-induced nephrotoxicity by nutrition regulation, and had a guiding effect on the clinical supplementation of nutritional elements.

Microbiological Safety and Quality Assessment of Maize (Zea mays L) Produced and Stocked from Rural Conditions in Côte D’ivoire

Aims: Fungal pathogens are one of the main biological agents causing maize post-harvest loss and affect food security in the country. Thus, this study was conducted to assess fungal pathogens associated to post-harvest maize (Zea mays L.) with especial focus to mycotoxin-producing fungi at producer’s storage condition in different regions of Côte d’Ivoire.
 Study Design: A total of 1 500 samples of maize as grains, cobs and husks were collected at rate of 500 samples by region (Gbêkê, Poro, Hambol, Indénié-Djuablin and Gontougo) and sent to the laboratory in order to analyse their sanitary quality.
 Place and Duration of Study: This study was carried out during March 2016 to January 2017. The analyses of the collected sample carried out at the Biotechnology, Agriculture and Valorisation of Biological Resources Laboratory of the Félix Houphouët-Boigny’s University, Abidjan.
 Methodology: Microbiological analysis was assessed by recording the number of colony in the plate. The contents of aflatoxin and ochratoxin A in the different samples were determined using standard methods.
 Results: The total microbial species isolated ranged from 104 to 1011 cfu/g with thermotolerants coliforms (103 – 104) and fecal coliforms (102 – 103). The stored maize samples contained also high amount of yeast and molds (104 to 107 cfu/g). Aspergillus genus was the predominantly fungal isolated in all maize samples with tree species which are A. flavus, A. niger and A. versicolor potential producers of mycotoxins. More importantly, stored maize sample as grain, cobs and husks were affected by aflatoxins (B1, B2, G1 and G2) and ochratoxin A. Sixty per cent of the maize samples, mostly husks, showed aflatoxin B1 (from 12.73 to 130.31 µg/kg) and OTA (from 16.75 to 134.21 µg/kg) concentrations above the Maximum Authorized Limit of 5 µg/kg.
 Conclusion: A significant variability from one region to another can be noticed at level of maize quality regardless the type of maize. The sanitary quality of maize seems to be tied to postharvest treatments (drying), type of storage (grains, cobs and husks) and structure of storage.

An Ochratoxin A Electrocatalytic Sensor Based on Electron Mediator Decorated Nanoalloy Biomimetic Enzyme Coupling with Label-Free Hair Aptamer

An electrocatalytic sensor based on electron mediator toluidine blue (Tb) decorated PtPd nanoalloys (PtPdNAs) biomimetic enzyme coupling with label-free hair aptamer (HA) for OTA detection was successfully constructed. In this work, label-free HA was designed containing anti-OTA aptamer sequence (APT) and complementary sequence (cDNA) of report DNA (rDNA). rDNA and Tb joint decorated PtPdNAs (Tb-PtPd-rDNA) was used as a signal probe. The peroxidase-like activity of the PtPdNAs combined with the synergistic catalysis of the Poly 3,4-ethoxylene dioxy thiophene-AuNPs (PEDOT-AuNPs) coated glass-carbon electrode (PE-Au/GCE) resulted in strong catalytic current of Tb and eventually significantly improved the sensitivity of the sensor. The response current had a good metrological-signal relationship with OTA concentration from 0.1 pg ml-1 to 0.1 ng ml-1, and the low detection limit of 0.05 pg ml-1 was obtained. Meanwhile, the proposed sensor exhibited a good correlation with HPLC when it was applied for OTA detection in red wine samples. The strategy broadens the design of catalytic sensor and can be applied to the detection of other small molecules.

A signal amplification of p DNA@Ag2S based photoelectrochemical competitive sensor for the sensitive detection of OTA in microfluidic devices

In this work, a signal amplification competitive-type photoelectrochemical system comprised of bismuth sulfide/bismuth oxyiodide/zinc oxide (Bi2S3/BiOI/ZnO) nano-array as platform and Ag2S-modified aptamers probe DNA (p DNA@Ag2S) as competition content for rapid and sensitive detection of OTA in microfluidic devices. The BiOI nano-array was first growth on surfaces of ZnO by a simple electrodeposited method, which provided large specific surface area and high stability to solve distribution of sensing platform and loose of combination of sensing substrate. Then, the Bi2S3 could be in-situ growth by self-sacrificial part Bi3+ of BiOI to form heterojunction without destroying the structure of the nano-array. A strong photocurrent intensity was acquired by the Bi2S3/BiOI/ZnO modified onto indium tin oxide (ITO) electrode, due to its good matching cascade band-edge levels could improve efficient separation of photo-generated e-/h+ pairs. After immobilizing with the capture DNA (c DNA) and the sequential hybridization of p DNA@Ag2S, the photocurrent intensity reduced obviously because part photo-generated electron transformed to Ag2S rather than Bi2S3/BiOI/ZnO electrode. Subsequently, the photocurrent intensity increased evident when immobilized the target OTA, owing to the OTA could bind the p DNA@Ag2S to form the specific-complex that were released from the electrode surface. Under optimal conditions, the prepared PEC microfluidic sensor exhibited a linear concentration of OTA from 0.01 pg/mL to 200 ng/mL with a low detection limit of 0.0035 pg/mL (S/N = 3). Furthermore, it achieved high sensitivity, good specificity, and acceptable stability and further provided an efficient method for sensitive detection of other target mycotoxins in practical application.

Ocratoxina A en café.


 La ocratoxina A es una micotoxina con actividad nefrotóxica, hepatotóxica, embriotóxica, teratogénica, neurotóxica, inmunotóxica, genotóxica y cancerígena producida por hongos filamentosos que se puede encontrar en productos como granos, nueces, especies, cerveza, café, entre otros. 
 El proceso de producción del café no elimina la ocratoxina, por lo que organizaciónes como el CODEX Alimentarius han establecido una serie de prácticas que minimizan la probabilidad de que esta toxina se encuentre en este producto. A nivel internacional, varios países han establecido la concentración máxima permitida de OTA en café, sin embargo, Costa Rica no lo ha definido todavía. 
 Existen estudios que demuestran la presencia de esta toxina en diferentes presentaciones de café. En el caso de Costa Rica, en el año 2007 se publicó un estudio donde se encontró ocratoxina A en producto puesto a la venta en niveles inferiores a los máximos permitidos en otros países. Esto evidencia que nuestro país no está exento de esta problemática, que se requieren más estudios al respecto y que finalmente se establezcan las concentraciones máximas permitidas de ocratoxina A en café.

A multi-endpoint approach to the combined toxic effects of patulin and ochratoxin a in human intestinal cells

Humans can be exposed to a complex and variable combination of mycotoxins. After ingestion, intestinal mucosa constitutes the first biological barrier that can be exposed to high concentrations of these toxins. The present study aimed to characterize the combined cytotoxicity, genotoxicity and impact on the gastrointestinal barrier integrity of patulin (PAT, 0.7 μM to 100 μM) and ochratoxin A (OTA, 1 μM to 200 μM) mixtures in Caco-2 cells. A dose-ratio deviation was verified for cytotoxicity, implying that OTA was mainly responsible for synergism when dominant in the mixture, while this pattern was changed to antagonism for the highest PAT concentrations. Genotoxicity (comet assay) results were compatible with an interactive DNA damaging effect at the highest PAT and OTA concentrations, not clearly mediated by the formation of oxidative DNA breaks. Regarding gastrointestinal barrier integrity, a potential synergism was attained at low levels of both mycotoxins, changing to antagonism at higher doses. The present results indicate that combined mycotoxins effects may arise at the intestinal level and should not be underestimated when evaluating their risk to human health.

Highly reproducible ratiometric aptasensor based on the ratio of amplified electrochemiluminescence signal and stable internal reference electrochemical signal

A highly reproducible ratiometric aptasensor has been developed based on the ratio of the enhanced electrochemiluminescence (ECL) signal and the stable electrochemistry signal for the first time. The ECL signal tag (Ru(phen)32+-DNA) was chosen as working probe (Ru(phen)32++-wp) and electrochemistry signal tag (methylene blue-DNA) as reference probe (MB-rp). The hybridization of Ru(phen)32++-wp and MB-rp in one structure insured the interdependence of two signals on the same sensing interface. OTA was chosen as a target model in this work and substrate DNA (sDNA) was designed to hybridize with OTA-aptamer (OTA-APT) in part, as well as the triggered chain of hybridization chain reaction (HCR). Only ECL signal of Ru(phen)32+-wp increased with the OTA existence while the electrochemical signal from MB-rp was stable as inter reference signal. The ratio value of the ECL/electrochemistry had a linear relationship with OTA concentration in the range of 12.40 pM to 6.19 nM with a correlation coefficient of 0.990, and the limit of detection was 5.6 pM. The proposed ECL ratiometric aptasensor has better reproducibility than that of the traditional ECL biosensor and been applied to detect OTA in real samples with satisfied results.

Assessment of Ochratoxin A in Commercial Corn and Wheat Products

Background: The objective of this study was to investigate the OTA concentration in different commercially available corn and wheat products. Methods: Corn and wheat-based collected samples were categorized as corn flakes (n=5), corn flour (n=5), oil popped popcorn (n=5), air-popped popcorn (n=5), commercial wheat flour (n=5), white flour (n=5), biscuits (n=5) and bread (n=5). The extraction solvent (acetonitrile and water 84:16 v/v) and MycoSep-229 column were applied for the clean-up purpose; subsequently, the liquid chromatography technique was used. Results: OTA was detected in 3 (60%), 1 (20%), 1 (20%), 1 (20%), 3 (60%) and 2 (40%) out of forty samples (n=40) including corn flour and corn flakes, wheat flour, white flour, bread and biscuits samples, respectively. The highest detected level was measured as 360 ng g-1 of OTA in a biscuit sample. The OTA level in positive samples (30 out of 40; 75%) was above the maximum established level by European Union regulations. Conclusion: In the present study significant variation in ochratoxin A content was observed in the corn and wheat samples ranging from 0-25.90 ng g-1. Further assessments in other similar products as well as conducting the required improvements in order to reduce the level of OTA were recommended. Keywords: Mycotoxins, ochratoxin A, liquid chromatography, corn products, wheat products, european union regulations.

Occurrence of Ochratoxin a in Animal Tissues and Feeds in Poland in 2014-2016.

IntroductionOchratoxin A (OTA) is a toxic metabolite mainly produced by Aspergillus spp. and Penicillum spp. fungi. Research on the contamination of cereals, complete feeds, and tissues with this mycotoxin has indicated that it can be a toxicological problem impacting animal health and food safety in temperate climes. OTA contamination mainly besets the global pig industry, necessitating the monitoring of feeds and animal tissues. The aim of the study was to present the results of the official monitoring of OTA in animal tissues and feeds in Poland in 2014–2016 and determine the possible correlation between the presence of OTA in different types of samples.Material and MethodsThe presence of ochratoxin A was determined using accepted procedures based on liquid chromatography with fluorescence detection after immunoaffinity column clean-up. Determination of OTA was afforded in the range of 0.3 µg/kg to 300 µg/kg in complete feeds and from 0.2 µg/kg to 150 µg/kg in the kidneys, liver, and muscles.ResultsOver the three year span, about 23.5% of the animal tissues samples were contaminated by ochratoxin A. In the 2014 survey, 10% of the sample tissues contained 5–10 µg/kg (only one sample above 10 μg/kg), and in 2015 and 2016, 24% of samples showed levels above the limit of quantification 0.2 μg/kg, while none of the samples exceeded the established provisional action level of 5 μg/kg for animal tissues. The animal feed analysis showed that 9% was contaminated with ochratoxin A above the limit of quantification of 0.3μg/kg. In 2% of feed samples the OTA concentration was greater than 50 μg/kg.ConclusionThe results confirm the appropriacy of OTA contamination monitoring and help to increase food safety.

Competitive immunoassay for Ochratoxin a based on FRET from quantum dot-labeled antibody to rhodamine-coated magnetic silica nanoparticles

We report on a highly sensitive competitive immunoassay for the mycotoxin Ochratoxin (OTA) using magnetic silica nanoparticles (NPs) fluorescently labeled with rhodamine 123 (Rho123) as signal intensifier. The method is based on the measurement of fluorescence resonance energy transfer (FRET) that occurs from CdTe quantum dots covered with anti-OTA antibody to the dye Rho123 on the surface of the NPs. The immunoreaction between anti-OTA antibody and OTA brings the fluorophore (acting as the acceptor) in close proximity of the QDs (acting as the donor), and this causes FRET to occur upon photo-excitation of the QDs. The size and polydispersity of the silica coated magnetic NPs was studied via TEM. The method has a detection limit of 0.8 pg of OTA per mL. It was applied to the determination of OTA in spiked human serum. A linear relationship is found between the increase in the fluorescence intensity of Rho 123 at 580 nm and the concentration of OTA in spiked samples over the 8 to 48 pg⋅mL−1 concentration range. This highly sensitive homogeneous competitive detection scheme is simple, rapid and efficient. It does not require multiple separation steps and excessive washing.

STUDY OF CONTAMINATION LEVEL OF OCHRATOXIN (A) IN IMPORED GRAINS WHEAT AND ITS PRODUCTS AT SOME LIBYAN FACTORIES

This study was conducted to determine the present of Ochratoxin (A) (OTA) to the number of 50 samples of wheat grain from varieties of soft wheat (Tricticm astivum) and hard (T. durm), and its products from some Libyan Mills (from the north-west and south-east and north) by using a technique (IAC) immunoaffinity columns cleaning and HPLC-FD to detect, with an overall average rate of recovery of the samples of wheat and grain products and fungal isolates 86.59 ± 0.03% and 89.19 ± 0.01%, respectively. The results showed that 96% of the samples were positive for OTA, with the average concentration of OTA from different regions reached the highest concentration of 0.0928μg/kg for soft wheat. The average concentration of the OTA in the different areas that have been grain assembly resulted the highest concentration of 0.0918 μg kg-1 for soft wheat for the Western Region, followed by 0.0783 and 0.020 < μg kg-1 for the eastern and southern region respectively, while the average concentration of the OTA for hard wheat 0.0307 and 0.3316 μg kg-1 of eastern and western region respectively. However all the samples contain levels of OTA are below the limit recommended by Libyan Standards Specification and European Commission Regulation Standard. Results of statistical analysis also showed no significant differences of (P≤ 0.01) of the concentration of the for hard and soft types wheat between regions , and for soft wheat products between regions while there was significant differences between hard wheat products at level of (P≤ 0.01). The results showed that the overall average for the moisture content of the samples by region ranged between 10.6, 11.10% for soft wheat for the southern region and western region respectively, 9.54 and 10.08% for hard wheat to the western and eastern region respectively. Results also showed that the overall average for the moisture content of soft wheat products (flour) between different regions was (13.03, 11.78, 8.58%) to the north-east, north-west and south-west respectively. Hard wheat products did not exceed 13.33, 10.76% for the southern- west and north-east reigions of semolina and pasta respectively, while was within the limit to the Codex Alimentarius Commission. the results of the statistical analysis and the presence of highly significant for moisture content between types of soft wheat and hard within regions and this also applies to soft wheat and hard products between the regions at the level of (P≤ 0.01).

Activity of Ganoderma lucidum on Serum Marker Enzymes in Ochratoxin a treated albino rat models

The study aims to determine the effects of Ganoderma lucidum in altering serum enzymes in ochratoxin A intoxicated albino rats. Animals were divided into six groups of seven rats and administered different concentrations of OTA and crude extract of the fungus while ochratoxin A doses were administered intraperineally once. The blood urea content after sacrificing was between 0.8±6.5 mg/dL and 20.2±5.8 mg/dL, alkaline phosphatase recorded the highest value for animals in Group 6 (98.3±2.9 U/L) with both enzymes being significantly different at p=0.05 within the groups. The serum globulin values were 39±1.8 g/L (control), 49.3±0.9 g/L (group 4), and 49.7±0.88 g/L (group 3). Alanine aminotransferase levels were significantly different from group to group at p=0.05 with animals in group 5 giving the highest value 64.3±1.8 U/L . Serum aspartate aminotransferase recorded the highest value for animals in Group 3 (109.3±1.5 U/L). The study showed that G. lucidum have the capacity to effect ameliorative, healing, scavenging, and restoring activities on serum enzymes which ultimately will improve the total well being of animals exposed to ochratoxin A, but at the same time, the challenge of weight loss resulting from food withdrawal need to be addressed.