Background Ochratoxin A(OTA)is a mycotoxin widely present in raw food and feed materials and is mainly pro-duced by Aspergillus ochraceus and Penicillium verrucosum.Our previous study showed that OTA principally induc...Background Ochratoxin A(OTA)is a mycotoxin widely present in raw food and feed materials and is mainly pro-duced by Aspergillus ochraceus and Penicillium verrucosum.Our previous study showed that OTA principally induces liver inflammation by causing intestinal flora disorder,especially Bacteroides plebeius(B.plebeius)overgrowth.However,whether OTA or B.plebeius alteration leads to abnormal tryptophan-related metabolism in the intestine and liver is largely unknown.This study aimed to elucidate the metabolic changes in the intestine and liver induced by OTA and the tryptophan-related metabolic pathway in the liver.Materials and methods A total of 30 healthy 1-day-old male Cherry Valley ducks were randomly divided into 2 groups.The control group was given 0.1 mol/L NaHCO3 solution,and the OTA group was given 235μg/kg body weight OTA for 14 consecutive days.Tryptophan metabolites were determined by intestinal chyme metabolomics and liver tryptophan-targeted metabolomics.AMPK-related signaling pathway factors were analyzed by Western blot-ting and mRNA expression.Results Metabolomic analysis of the intestinal chyme showed that OTA treatment resulted in a decrease in intesti-nal nicotinuric acid levels,the downstream product of tryptophan metabolism,which were significantly negatively correlated with B.plebeius abundance.In contrast,OTA induced a significant increase in indole-3-acetamide levels,which were positively correlated with B.plebeius abundance.Simultaneously,OTA decreased the levels of ATP,NAD+and dipeptidase in the liver.Liver tryptophan metabolomics analysis showed that OTA inhibited the kynurenine metabolic pathway and reduced the levels of kynurenine,anthranilic acid and nicotinic acid.Moreover,OTA increased the phosphorylation of AMPK protein and decreased the phosphorylation of mTOR protein.Conclusion OTA decreased the level of nicotinuric acid in the intestinal tract,which was negatively correlated with B.plebeius abundance.The abnormal metabolism of tryptophan led to a deficiency of NAD+and ATP in the liver,which in turn activated the AMPK signaling pathway.Our results provide new insights into the toxic mechanism of OTA,and tryptophan metabolism might be a target for prevention and treatment.展开更多
Ochratoxin A (OA) is a mycotoxin which has been found to occur in foods of plant origin, in edible animal tissues, as well as in human blood sera and tissues. The ability of OA to move up the food chain is aided by it...Ochratoxin A (OA) is a mycotoxin which has been found to occur in foods of plant origin, in edible animal tissues, as well as in human blood sera and tissues. The ability of OA to move up the food chain is aided by its long half-life in certain edible animal species. In this report, an evaluation of the health risks to Canadians due to the presence of OA in food products is presented. The first part of the report deals with the physicochemical aspects, mycology, laboratory production, analytical methods, and natural occurrence in plant products, animal products, and human tissues. The stability of OA in foods and feeds, the effects of food processing, and the removal from foods and feeds by physicochemical means are also discussed. From these data, the worst case estimate for the daily exposure of Canadians to OA, from the consumption of pork-based food products and cereal foods, is approximately 5 ng OA/kg body wt (mean of eaters) for young children, the highest consumption group on a body weight basis. The second part of the report deals with the metabolic disposition as well as the available toxicity database for OA in laboratory animals, farm animals, and humans. The major target for OA toxicity in all mammalian species tested is the kidney, and endemic nephropathies affecting livestock as well as humans have been attributed to OA. OA is also teratogenic, and in the fetus the major target is the developing central nervous system. Recent studies have provided 'clear evidence' of the carcinogenicity of OA in two rodent species. OA was found to be nonmutagenic in various microbial and mammalian gene mutation assays, but weak genotoxic activity to mammalian cells was noted. In addition, OA was found to suppress immune function. Based on the NTP carcinogenicity study with OA in rats, the estimated tolerable daily intake in humans ranges from 0.2 to 4.2 ng OA/kg body wt, depending on the method of extrapolation used. In view of the toxic properties of OA, it is recommended that exposure to OA be kept to a minimum. In Canada, further monitoring programs are required to better define the overall residue profile of OA in cereal grains, animal feeds, animal food products, and human blood. Such data are required to better assess dietary exposure and to ascertain the need for regulatory controls or other control mechanisms. (c)1989 Academic Press, Inc.展开更多
Ochratoxin A (OTA) is among the most important mycotoxins, and the International Agency for Research on Cancer (IARC) classifies it as possibly carcinogenic to humans (group 2B). A total of 121 samples of dried fruits...Ochratoxin A (OTA) is among the most important mycotoxins, and the International Agency for Research on Cancer (IARC) classifies it as possibly carcinogenic to humans (group 2B). A total of 121 samples of dried fruits from the central zone of Iran were analyzed for OTA by enzyme linked immunosorbent assay (ELISA) technique. The recovery percentages of OTA in spiked dried fruit samples at concentrations of 5, 10 and 20 ng/g were found to be 84.9%, 89.3% and 90.4% as mean, respectively. OTA was found in 20.7% of the analyzed samples by average concentration of 6.7 ± 3.9 ng/g. The incidence rates of OTA contamination in dried fig, raising, apricots, and date samples were 10.4%, 44.7%, 6.7% and 10.0%, respectively. The concentrations of OTA in 7.9% of contaminated dried raising samples and 2.1% of dried fig samples were higher than maximum tolerance limit accepted by European Union (10 ng/g). This value reflects that the analyzed samples have a minimal contribution to toxicological risk. To our best knowledge, the present study is the first report of the presence of OTA by ELISA in dried fruit samples in Iran.展开更多
In order to generate an antibody against a small hapten molecule, the hapten is cross-linked with carrier protein to make it immunogenic. In this study, the hapten (ochratoxin A, OTA) was coupled to ovalbumin (OVA...In order to generate an antibody against a small hapten molecule, the hapten is cross-linked with carrier protein to make it immunogenic. In this study, the hapten (ochratoxin A, OTA) was coupled to ovalbumin (OVA) by an active ester reaction. To develop a technique for detecting the conjugation, the hapten-protein conjugate (OTA-OVA) was characterized thoroughly by immunoarray technology, ultraviolet (UV) spectroscopy and matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF-MS), respectively. The molecular weight of OTA-OVA was 50 350.141 Da, and the molecular weight of OVA was 44 887.506 Da, which were determined by MALDI-TOF-MS, respectively. In OTA-OVA, the molecular coupling ratio was 13:1 by MALDI-TOF-MS while the molecular coupling ratio was 10:1 by UV. In this experiment, UV and MALDI-TOF-MS were selected as the efficient methods to evaluate the cross-linking effect and calculate the molecular coupling ratio.展开更多
Ochratoxin A(OTA),one of the most dangerous mycotoxins for human health,has been subjected to numerous studies for separation and detection in minimal amounts.Aptamers as novel recognition elements have been employed ...Ochratoxin A(OTA),one of the most dangerous mycotoxins for human health,has been subjected to numerous studies for separation and detection in minimal amounts.Aptamers as novel recognition elements have been employed to fabricate ultrasensitive biosensors for the detection of OTA and designing delicate analytical tools.This review attempted to comprehensively examine all reported aptamer-based detection and separation platforms for ochratoxin.The most relevant databases were considered to discover all specific aptamers for dealing with OTA.Aptamer-based detection and separation devices specified for OTA were searched for,analyzed,discussed,and classified based on their specifications.The optical aptasensors have gathered a higher interest than electrochemical aptasensors,which can achieve a lower limit of detections.Moreover,some extraction platforms based on these aptamers were also found.However,aptamer-based devices seem to have some challenges in their application.展开更多
Ochratoxin-A[7-(L-β-phenylalanylcarbonyl)-carboxyl-5-chloro-8-hydroxy-3,4-dihydro-3R-methyl-isocumarin, OTA] is a common food contaminant mycotoxin that enters the human body through the consumption of improperly sto...Ochratoxin-A[7-(L-β-phenylalanylcarbonyl)-carboxyl-5-chloro-8-hydroxy-3,4-dihydro-3R-methyl-isocumarin, OTA] is a common food contaminant mycotoxin that enters the human body through the consumption of improperly stored food products. Upon ingestion, it leads to immuno-suppression and immuno-toxicity. OTA has been known to produce nephrotoxic, teratogenic, and carcinogenic activity (via oxidative DNA damage) in several species. This review introduces potentials of electrochemical biosensor to provide breakthroughs in OTA detection through improved selectivity and sensitivity and also the current approaches for detecting OTA in food products.展开更多
Ochratoxin A (OTA) is a secondary metabolite of Asper-gillus and Penicillium, microorganisms that can be haz-ardous to health when present as food contaminants. OTA is a potent member of a group of mycotoxins. Prolong...Ochratoxin A (OTA) is a secondary metabolite of Asper-gillus and Penicillium, microorganisms that can be haz-ardous to health when present as food contaminants. OTA is a potent member of a group of mycotoxins. Prolonged exposure to mycotoxins in the diet is related to cancer, among other diseases. Hepatocellular car-cinoma (HCC) accounts for 70%-90% of primary liver cancers and is the third leading cause of cancer-related deaths worldwide. In a recent study, Ibrahim et al proposed a correlation between the incidence of HCC and contamination with OTA. Analysis of OTA in serum samples showed that HCC patients had the highest incidence of OTA of the subjects examined (5-fold higher than that of the control group). OTA levels were significantly increased in HCC patients. This study demonstrates that chronic exposure to high levels of OTA may be associated with a high risk of liver cancer development. Future epidemiologic studies of HCC should focus on good practices in food preparation, food storage and the consumption of OTA-containing foods.展开更多
The simple rapid and sensitive enzyme-linked immunosorbent assay (ELISA) methods, di-rect and indirect ELISA, for quantitation of ochratoxin A in cereal had been developed by theutilization of monoclonal antibody on i...The simple rapid and sensitive enzyme-linked immunosorbent assay (ELISA) methods, di-rect and indirect ELISA, for quantitation of ochratoxin A in cereal had been developed by theutilization of monoclonal antibody on immunomicroplate. Direct FLIAS was found to be less timeconsuming than indirect ELISA. For direct FLISA, recovery of 1 -500 ppb OA added to wheat was78.9-100.0% and rice was 88.9- 120.0%. For indirect EI.IAS, recovery of 1-500 ppb OA addedto wheat was 79.0- 110.0% and rice was 82.0 120.0%. The minimal detection level for OA was Ippb. Analyses of 31 samples that caused humanintoxicant for OA showed that the ELISA resultsagreed wtll with those obtained by thin-layer chromatogrdphy.展开更多
Phenylalanine, isocoumarin and Ochratoxin A (OTA) have been intercalated within the interlayer space of layered double hydroxides. Synthesis of these nanocompounds was achieved via co-precipitation. Their physicochemi...Phenylalanine, isocoumarin and Ochratoxin A (OTA) have been intercalated within the interlayer space of layered double hydroxides. Synthesis of these nanocompounds was achieved via co-precipitation. Their physicochemical properties were studied by element chemical analysis, powder X-ray diffraction, infrared spectroscopy and thermal analyses. The presence of OTA in the interlayer is demonstrated by the study of LC-FD Analysis. On the other hand, these studies allow to check how some of the toxin is on the surface of the nanocomposite.展开更多
Occurrence of citrinin and ochratoxin A in different feed ingredients and compound feeds was screened by accredited methods based on the indirect competitive enzyme-linked immunosorbent assay. High frequency co-occurr...Occurrence of citrinin and ochratoxin A in different feed ingredients and compound feeds was screened by accredited methods based on the indirect competitive enzyme-linked immunosorbent assay. High frequency co-occurrence of both toxins was found in wheat grain and processed sunflower seeds. Citrinin levels exceeded those of ochratoxin A in the majority of co-contaminated feed samples, and the ratio of (1.1 - 10):1 proved to be the most frequent. A possible role of Aspergillus and Penicillium fungi in separate and simultaneous OTA and CIT occurrence in feeds is also discussed.展开更多
The aim of the current study was to prepare organo-modified nano montmorillonite (OMNM) and to evaluate its chemopreventive effects against the hapatonephrotoxicity induced by aflatoxin B1 (AFB1) and ochratoxin A (OA)...The aim of the current study was to prepare organo-modified nano montmorillonite (OMNM) and to evaluate its chemopreventive effects against the hapatonephrotoxicity induced by aflatoxin B1 (AFB1) and ochratoxin A (OA) singly or in combination in rats. OMNM was prepared using Cetyltrimethylammoniumbromide (CTAB) as organic modifier. Eighty male Sprague Dawley were divided into 8 groups and treated for 8 weeks as follow: the control group;the group treated orally with AFB1 (80 μg/kg b.w.);the group treated with OA (100 μg/kg b.w.);the group treated with AFB1 plus OA, the group treated with OMNM (5 g/kg diet) and the groups treated with AFB1 and/or OA plus OMNM. At the end of treatment period, blood and tissue samples were collected from all animals for biochemical and histological analysis. The results revealed that the expansion in the basal spacing of the montmorillonite due to the intercalation of CTAB was 7.20?Å and the average particle size of OMNM was 120 nm. The in vivo results indicated that treatment with both AFB1 and OA singly or in combination resulted in a significant increase in liver and kidney function parameters, oxidative stress and tumor markers accompanied with a significant decrease in antioxidant enzyme activities and significant histological changes in liver and kidney tissues. These changes were severe in the group received the combined treatment of AFB1 and OA. OMNM alone did not show any toxic effect and it succeeded to prevent or at least diminish the toxic effects and the histological changes in liver and kidney. It can be concluded that treatment with AFB1 and OA has a synergistic toxic effects and OMNM is safe and it is a promise candidate as an additive to protect against the exposure to multi-mycotoxins in high risk population.展开更多
Background Ochratoxin A(OTA),a globally abundant and extremely hazardous pollutant,is a significant source of contamination in aquafeeds and is responsible for severe food pollution.The developmental toxicity of OTA a...Background Ochratoxin A(OTA),a globally abundant and extremely hazardous pollutant,is a significant source of contamination in aquafeeds and is responsible for severe food pollution.The developmental toxicity of OTA and the potential relieving strategy of natural products remain unclear.This study screened the substance curcumin(Cur),which had the best effect in alleviating OTA inhibition of myoblast proliferation,from 96 natural products and investigated its effect and mechanism in reducing OTA myotoxicity in vivo and in vitro.Methods A total of 720 healthy juvenile grass carp,with an initial average body weight of 11.06±0.05 g,were randomly assigned into 4 groups:the control group(without OTA and Cur),1.2 mg/kg OTA group,400 mg/kg Cur group,and 1.2 mg/kg OTA+400 mg/kg Cur group.Each treatment consisted of 3 replicates(180 fish)for 60 d.Results Firstly,we cultured,purified,and identified myoblasts using the tissue block culture method.Through preliminary screening and re-screening of 96 substances,we examined cell proliferation-related indicators such as cell viability and ultimately found that Cur had the best effect.Secondly,Cur could alleviate OTA-inhibited myoblast differentiation and myofibrillar development-related proteins(Myo G and MYHC)in vivo and in vitro and improve the growth performance of grass carp.Then,Cur could also promote the expression of OTA-inhibited protein synthesis-related proteins(S6K1 and TOR),which was related to the activation of the AKT/TOR signaling pathway.Finally,Cur could downregulate the expression of OTA-enhanced protein degradation-related genes(murf1,foxo3a,and ub),which was related to the inhibition of the Fox O3a signaling pathway.Conclusions In summary,our data demonstrated the effectiveness of Cur in alleviating OTA myotoxicity in vivo and in vitro.This study confirms the rapidity,feasibility,and effectiveness of establishing a natural product screening method targeting myoblasts to alleviate fungal toxin toxicity.展开更多
A label-free fluorescent aptasensor for specific and ultrasensitive monitoring ochratoxin A(OTA) was developed using the specific aptamer of OTA(OSA) as recognition dement, an aggregation-induced emission(AIE) m...A label-free fluorescent aptasensor for specific and ultrasensitive monitoring ochratoxin A(OTA) was developed using the specific aptamer of OTA(OSA) as recognition dement, an aggregation-induced emission(AIE) molecule(a 9,10-distyrylanthracene with two ammonium groups, DSAI) as a fluorescent probe, and graphene oxide(GO) as a quencher. In the absence of OTA, the AIE probe DSAI and OSA complex(DSAI/OSA) is adsorbed on the GO surface, and the fluorescence of DSAI will be quenched efficiently via the fluorescence resonance energy transfer(FRET) from DSAI to GO. Upon the OTA addition, a more stable complex(OSA-OTA) is formed and released from GO. Meanwhile, DSAI and OSA-OTA can form a new complex(DSAI/OSA-OTA), then the fluorescent signal of DSAI recovers gradually. Therefore, by introducing GO and DSAI, the fluorescence signal of DSAI can be easily turned from "off" to "on" after the addition of OTA, and the ultrasensitive detection of OTA by monitoring the change of the fluorescence signal of DSAI can be readily realized. The detection limit of the assay can reach 0.324 nmol/L with a linear detection range of 10-200 nmol/L. And the aptasensor exhibits high selectivity for OTA against other analogues. Moreover, it has been successfully applied for the detection of OTA in red wine samples.展开更多
基金Guangdong Province Natural Science Funds for Distinguished Young Scholar(2022B1515020016)the National Science Fund for Outstanding Young Scholars(32222080)+5 种基金National Key Research Program(2021YFD1300404)National Science Fund Project of China(32072751)Guangdong Basic and Applied Basic Research Foundation(2022B1515130003)China Agriculture Research System(CARS-42-15)Modern Agricultural Industrial Technology System Innovation Team of Guangdong Province(2022KJ137)Natural Science Foundation of Guangdong Province(2019B1515210012).
文摘Background Ochratoxin A(OTA)is a mycotoxin widely present in raw food and feed materials and is mainly pro-duced by Aspergillus ochraceus and Penicillium verrucosum.Our previous study showed that OTA principally induces liver inflammation by causing intestinal flora disorder,especially Bacteroides plebeius(B.plebeius)overgrowth.However,whether OTA or B.plebeius alteration leads to abnormal tryptophan-related metabolism in the intestine and liver is largely unknown.This study aimed to elucidate the metabolic changes in the intestine and liver induced by OTA and the tryptophan-related metabolic pathway in the liver.Materials and methods A total of 30 healthy 1-day-old male Cherry Valley ducks were randomly divided into 2 groups.The control group was given 0.1 mol/L NaHCO3 solution,and the OTA group was given 235μg/kg body weight OTA for 14 consecutive days.Tryptophan metabolites were determined by intestinal chyme metabolomics and liver tryptophan-targeted metabolomics.AMPK-related signaling pathway factors were analyzed by Western blot-ting and mRNA expression.Results Metabolomic analysis of the intestinal chyme showed that OTA treatment resulted in a decrease in intesti-nal nicotinuric acid levels,the downstream product of tryptophan metabolism,which were significantly negatively correlated with B.plebeius abundance.In contrast,OTA induced a significant increase in indole-3-acetamide levels,which were positively correlated with B.plebeius abundance.Simultaneously,OTA decreased the levels of ATP,NAD+and dipeptidase in the liver.Liver tryptophan metabolomics analysis showed that OTA inhibited the kynurenine metabolic pathway and reduced the levels of kynurenine,anthranilic acid and nicotinic acid.Moreover,OTA increased the phosphorylation of AMPK protein and decreased the phosphorylation of mTOR protein.Conclusion OTA decreased the level of nicotinuric acid in the intestinal tract,which was negatively correlated with B.plebeius abundance.The abnormal metabolism of tryptophan led to a deficiency of NAD+and ATP in the liver,which in turn activated the AMPK signaling pathway.Our results provide new insights into the toxic mechanism of OTA,and tryptophan metabolism might be a target for prevention and treatment.
文摘Ochratoxin A (OA) is a mycotoxin which has been found to occur in foods of plant origin, in edible animal tissues, as well as in human blood sera and tissues. The ability of OA to move up the food chain is aided by its long half-life in certain edible animal species. In this report, an evaluation of the health risks to Canadians due to the presence of OA in food products is presented. The first part of the report deals with the physicochemical aspects, mycology, laboratory production, analytical methods, and natural occurrence in plant products, animal products, and human tissues. The stability of OA in foods and feeds, the effects of food processing, and the removal from foods and feeds by physicochemical means are also discussed. From these data, the worst case estimate for the daily exposure of Canadians to OA, from the consumption of pork-based food products and cereal foods, is approximately 5 ng OA/kg body wt (mean of eaters) for young children, the highest consumption group on a body weight basis. The second part of the report deals with the metabolic disposition as well as the available toxicity database for OA in laboratory animals, farm animals, and humans. The major target for OA toxicity in all mammalian species tested is the kidney, and endemic nephropathies affecting livestock as well as humans have been attributed to OA. OA is also teratogenic, and in the fetus the major target is the developing central nervous system. Recent studies have provided 'clear evidence' of the carcinogenicity of OA in two rodent species. OA was found to be nonmutagenic in various microbial and mammalian gene mutation assays, but weak genotoxic activity to mammalian cells was noted. In addition, OA was found to suppress immune function. Based on the NTP carcinogenicity study with OA in rats, the estimated tolerable daily intake in humans ranges from 0.2 to 4.2 ng OA/kg body wt, depending on the method of extrapolation used. In view of the toxic properties of OA, it is recommended that exposure to OA be kept to a minimum. In Canada, further monitoring programs are required to better define the overall residue profile of OA in cereal grains, animal feeds, animal food products, and human blood. Such data are required to better assess dietary exposure and to ascertain the need for regulatory controls or other control mechanisms. (c)1989 Academic Press, Inc.
文摘Ochratoxin A (OTA) is among the most important mycotoxins, and the International Agency for Research on Cancer (IARC) classifies it as possibly carcinogenic to humans (group 2B). A total of 121 samples of dried fruits from the central zone of Iran were analyzed for OTA by enzyme linked immunosorbent assay (ELISA) technique. The recovery percentages of OTA in spiked dried fruit samples at concentrations of 5, 10 and 20 ng/g were found to be 84.9%, 89.3% and 90.4% as mean, respectively. OTA was found in 20.7% of the analyzed samples by average concentration of 6.7 ± 3.9 ng/g. The incidence rates of OTA contamination in dried fig, raising, apricots, and date samples were 10.4%, 44.7%, 6.7% and 10.0%, respectively. The concentrations of OTA in 7.9% of contaminated dried raising samples and 2.1% of dried fig samples were higher than maximum tolerance limit accepted by European Union (10 ng/g). This value reflects that the analyzed samples have a minimal contribution to toxicological risk. To our best knowledge, the present study is the first report of the presence of OTA by ELISA in dried fruit samples in Iran.
基金supported by the National High-Technology Research and Development Program of China (2007AA10Z429)the Stabling and Introducing Talents Fund Program of Anhui Agricultural University, China (WD2011-17)
文摘In order to generate an antibody against a small hapten molecule, the hapten is cross-linked with carrier protein to make it immunogenic. In this study, the hapten (ochratoxin A, OTA) was coupled to ovalbumin (OVA) by an active ester reaction. To develop a technique for detecting the conjugation, the hapten-protein conjugate (OTA-OVA) was characterized thoroughly by immunoarray technology, ultraviolet (UV) spectroscopy and matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF-MS), respectively. The molecular weight of OTA-OVA was 50 350.141 Da, and the molecular weight of OVA was 44 887.506 Da, which were determined by MALDI-TOF-MS, respectively. In OTA-OVA, the molecular coupling ratio was 13:1 by MALDI-TOF-MS while the molecular coupling ratio was 10:1 by UV. In this experiment, UV and MALDI-TOF-MS were selected as the efficient methods to evaluate the cross-linking effect and calculate the molecular coupling ratio.
文摘Ochratoxin A(OTA),one of the most dangerous mycotoxins for human health,has been subjected to numerous studies for separation and detection in minimal amounts.Aptamers as novel recognition elements have been employed to fabricate ultrasensitive biosensors for the detection of OTA and designing delicate analytical tools.This review attempted to comprehensively examine all reported aptamer-based detection and separation platforms for ochratoxin.The most relevant databases were considered to discover all specific aptamers for dealing with OTA.Aptamer-based detection and separation devices specified for OTA were searched for,analyzed,discussed,and classified based on their specifications.The optical aptasensors have gathered a higher interest than electrochemical aptasensors,which can achieve a lower limit of detections.Moreover,some extraction platforms based on these aptamers were also found.However,aptamer-based devices seem to have some challenges in their application.
文摘Ochratoxin-A[7-(L-β-phenylalanylcarbonyl)-carboxyl-5-chloro-8-hydroxy-3,4-dihydro-3R-methyl-isocumarin, OTA] is a common food contaminant mycotoxin that enters the human body through the consumption of improperly stored food products. Upon ingestion, it leads to immuno-suppression and immuno-toxicity. OTA has been known to produce nephrotoxic, teratogenic, and carcinogenic activity (via oxidative DNA damage) in several species. This review introduces potentials of electrochemical biosensor to provide breakthroughs in OTA detection through improved selectivity and sensitivity and also the current approaches for detecting OTA in food products.
文摘Ochratoxin A (OTA) is a secondary metabolite of Asper-gillus and Penicillium, microorganisms that can be haz-ardous to health when present as food contaminants. OTA is a potent member of a group of mycotoxins. Prolonged exposure to mycotoxins in the diet is related to cancer, among other diseases. Hepatocellular car-cinoma (HCC) accounts for 70%-90% of primary liver cancers and is the third leading cause of cancer-related deaths worldwide. In a recent study, Ibrahim et al proposed a correlation between the incidence of HCC and contamination with OTA. Analysis of OTA in serum samples showed that HCC patients had the highest incidence of OTA of the subjects examined (5-fold higher than that of the control group). OTA levels were significantly increased in HCC patients. This study demonstrates that chronic exposure to high levels of OTA may be associated with a high risk of liver cancer development. Future epidemiologic studies of HCC should focus on good practices in food preparation, food storage and the consumption of OTA-containing foods.
文摘The simple rapid and sensitive enzyme-linked immunosorbent assay (ELISA) methods, di-rect and indirect ELISA, for quantitation of ochratoxin A in cereal had been developed by theutilization of monoclonal antibody on immunomicroplate. Direct FLIAS was found to be less timeconsuming than indirect ELISA. For direct FLISA, recovery of 1 -500 ppb OA added to wheat was78.9-100.0% and rice was 88.9- 120.0%. For indirect EI.IAS, recovery of 1-500 ppb OA addedto wheat was 79.0- 110.0% and rice was 82.0 120.0%. The minimal detection level for OA was Ippb. Analyses of 31 samples that caused humanintoxicant for OA showed that the ELISA resultsagreed wtll with those obtained by thin-layer chromatogrdphy.
文摘Phenylalanine, isocoumarin and Ochratoxin A (OTA) have been intercalated within the interlayer space of layered double hydroxides. Synthesis of these nanocompounds was achieved via co-precipitation. Their physicochemical properties were studied by element chemical analysis, powder X-ray diffraction, infrared spectroscopy and thermal analyses. The presence of OTA in the interlayer is demonstrated by the study of LC-FD Analysis. On the other hand, these studies allow to check how some of the toxin is on the surface of the nanocomposite.
文摘Occurrence of citrinin and ochratoxin A in different feed ingredients and compound feeds was screened by accredited methods based on the indirect competitive enzyme-linked immunosorbent assay. High frequency co-occurrence of both toxins was found in wheat grain and processed sunflower seeds. Citrinin levels exceeded those of ochratoxin A in the majority of co-contaminated feed samples, and the ratio of (1.1 - 10):1 proved to be the most frequent. A possible role of Aspergillus and Penicillium fungi in separate and simultaneous OTA and CIT occurrence in feeds is also discussed.
文摘The aim of the current study was to prepare organo-modified nano montmorillonite (OMNM) and to evaluate its chemopreventive effects against the hapatonephrotoxicity induced by aflatoxin B1 (AFB1) and ochratoxin A (OA) singly or in combination in rats. OMNM was prepared using Cetyltrimethylammoniumbromide (CTAB) as organic modifier. Eighty male Sprague Dawley were divided into 8 groups and treated for 8 weeks as follow: the control group;the group treated orally with AFB1 (80 μg/kg b.w.);the group treated with OA (100 μg/kg b.w.);the group treated with AFB1 plus OA, the group treated with OMNM (5 g/kg diet) and the groups treated with AFB1 and/or OA plus OMNM. At the end of treatment period, blood and tissue samples were collected from all animals for biochemical and histological analysis. The results revealed that the expansion in the basal spacing of the montmorillonite due to the intercalation of CTAB was 7.20?Å and the average particle size of OMNM was 120 nm. The in vivo results indicated that treatment with both AFB1 and OA singly or in combination resulted in a significant increase in liver and kidney function parameters, oxidative stress and tumor markers accompanied with a significant decrease in antioxidant enzyme activities and significant histological changes in liver and kidney tissues. These changes were severe in the group received the combined treatment of AFB1 and OA. OMNM alone did not show any toxic effect and it succeeded to prevent or at least diminish the toxic effects and the histological changes in liver and kidney. It can be concluded that treatment with AFB1 and OA has a synergistic toxic effects and OMNM is safe and it is a promise candidate as an additive to protect against the exposure to multi-mycotoxins in high risk population.
基金financially supported by the earmarked fund for CARS(CARS-45)National Natural Science Foundation of China for Outstanding Youth Science Foundation(31922086)+1 种基金the Young Top-Notch Talent Support Programthe 111 project(D17015)。
文摘Background Ochratoxin A(OTA),a globally abundant and extremely hazardous pollutant,is a significant source of contamination in aquafeeds and is responsible for severe food pollution.The developmental toxicity of OTA and the potential relieving strategy of natural products remain unclear.This study screened the substance curcumin(Cur),which had the best effect in alleviating OTA inhibition of myoblast proliferation,from 96 natural products and investigated its effect and mechanism in reducing OTA myotoxicity in vivo and in vitro.Methods A total of 720 healthy juvenile grass carp,with an initial average body weight of 11.06±0.05 g,were randomly assigned into 4 groups:the control group(without OTA and Cur),1.2 mg/kg OTA group,400 mg/kg Cur group,and 1.2 mg/kg OTA+400 mg/kg Cur group.Each treatment consisted of 3 replicates(180 fish)for 60 d.Results Firstly,we cultured,purified,and identified myoblasts using the tissue block culture method.Through preliminary screening and re-screening of 96 substances,we examined cell proliferation-related indicators such as cell viability and ultimately found that Cur had the best effect.Secondly,Cur could alleviate OTA-inhibited myoblast differentiation and myofibrillar development-related proteins(Myo G and MYHC)in vivo and in vitro and improve the growth performance of grass carp.Then,Cur could also promote the expression of OTA-inhibited protein synthesis-related proteins(S6K1 and TOR),which was related to the activation of the AKT/TOR signaling pathway.Finally,Cur could downregulate the expression of OTA-enhanced protein degradation-related genes(murf1,foxo3a,and ub),which was related to the inhibition of the Fox O3a signaling pathway.Conclusions In summary,our data demonstrated the effectiveness of Cur in alleviating OTA myotoxicity in vivo and in vitro.This study confirms the rapidity,feasibility,and effectiveness of establishing a natural product screening method targeting myoblasts to alleviate fungal toxin toxicity.
文摘A label-free fluorescent aptasensor for specific and ultrasensitive monitoring ochratoxin A(OTA) was developed using the specific aptamer of OTA(OSA) as recognition dement, an aggregation-induced emission(AIE) molecule(a 9,10-distyrylanthracene with two ammonium groups, DSAI) as a fluorescent probe, and graphene oxide(GO) as a quencher. In the absence of OTA, the AIE probe DSAI and OSA complex(DSAI/OSA) is adsorbed on the GO surface, and the fluorescence of DSAI will be quenched efficiently via the fluorescence resonance energy transfer(FRET) from DSAI to GO. Upon the OTA addition, a more stable complex(OSA-OTA) is formed and released from GO. Meanwhile, DSAI and OSA-OTA can form a new complex(DSAI/OSA-OTA), then the fluorescent signal of DSAI recovers gradually. Therefore, by introducing GO and DSAI, the fluorescence signal of DSAI can be easily turned from "off" to "on" after the addition of OTA, and the ultrasensitive detection of OTA by monitoring the change of the fluorescence signal of DSAI can be readily realized. The detection limit of the assay can reach 0.324 nmol/L with a linear detection range of 10-200 nmol/L. And the aptasensor exhibits high selectivity for OTA against other analogues. Moreover, it has been successfully applied for the detection of OTA in red wine samples.