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Determination of six groups of mycotoxins in Chinese dark tea and the associated risk assessment
2020
Chinese dark tea is widely enjoyed for its multiple health-promoting effects and pleasant taste. However, its production involves fermentation by microbiota in raw tea, some of which are filamentous fungi and thus potential mycotoxin producers. Accordingly, whether mycotoxins pose health risk on dark tea consumption has become a public concern. In this study, a cleaning method of multi-functional column (MFC) and immunoaffinity column (IAC) in tandem combined to HPLC detection was developed and validated for determining ten mycotoxins of six groups (i.e., aflatoxins of B₁, B₂, G₁ and G₂, ochratoxin A, zearalenone, deoxynivalenol, fumonisins of B₁, B₂, and T-2) in dark teas. The interferences from secondary metabolites were effectively reduced, and the sensitivities and recoveries of the method were qualified for tea matrices. Six groups mycotoxins were determined in 108 samples representing the major Chinese dark teas by using the new method. Subsequently, the dietary exposure and health risks were evaluated for different age and gender groups in Kunming and Pu’er in China and Ulan Bator in Mongolia. The occurrence of zearalenone was 4.63% and that of ochratoxin A was 1.85%, with the other four groups mycotoxins were below the limits of quantification. The hazard index values for the five groups’ non-carcinogenic mycotoxins were far below 1.0. The deterministic risk assessment indicated no non-carcinogenic risks for dark tea consumption in the three areas. Probabilistic estimation showed that the maximum value of 95th percentile carcinogenic risk value for the aflatoxins was 2.12 × 10⁻⁸, which is far below the acceptable carcinogenic risk level (10⁻⁶). Hereby, six groups mycotoxins in Chinese dark tea showed no observed risk concern to consumers.
Afficher plus [+] Moins [-]Progress and challenges in sensing of mycotoxins using molecularly imprinted polymers
2022
Hua, Yongbiao | Ahmadi, Younes | Sonne, Christian | Kim, Ki Hyun
Mycotoxin is toxic secondary metabolite formed by certain filamentous fungi. This toxic compound can enter the food chain through contamination of food (e.g., by colonization of toxigenic fungi on food). In light of the growing concerns on the health hazards posed by mycotoxins, it is desirable to develop reliable analytical tools for their detection in food products in both sensitive and efficient manner. For this purpose, the potential utility of molecularly imprinted polymers (MIPs) has been explored due to their meritful properties (e.g., large number of tailor-made binding sites, sensitive template molecules, high recognition specificity, and structure predictability). This review addresses the recent advances in the application of MIPs toward the sensing of various mycotoxins (e.g., aflatoxins and patulin) along with their fabrication strategies. Then, performance evaluation is made for various types of MIP- and non-MIP-based sensing platforms built for the listed target mycotoxins in terms of quality assurance such as limit of detection (LOD). Further, the present challenges in the MIP-based sensing application of mycotoxins are discussed along with the future outlook in this research field.
Afficher plus [+] Moins [-]Hazards and control of aflatoxins
1994
El-Darawany, A.A. | Marai, I.F.M. (Department of Animal Production, Faculty of Agriculture, Zagazig University, Zagazig (Egypt))
Determination of Mycotoxigenic Fungi and Total Aflatoxins in Stored Corn from Sites of Puebla and Tlaxcala, Mexico
2024
K. Saez-Gomez, R. Avila-Sosa, M. Huerta-Lara, F. Avelino-Flores and R. Munguia-Pérez
This paper aimed to evaluate the contamination with mycotoxigenic fungi and total aflatoxins in stored corn from different sites in Puebla and Tlaxcala, Mexico. Methodology. The study was conducted at two sites in Puebla (San Salvador El Seco and Junta Auxiliar La Resurrección) and two sites in Tlaxcala (Tlaltepango and Nativitas). A total of 80 samples of stored corn were collected. Identification of Aspergillus flavus was performed by microculture techniques and specific taxonomic keys (macromorphological and micromorphological). Then, samples of contaminated corn were selected, and aflatoxin production was confirmed using a direct solid-phase ELISA kit. A total of 25 A. flavus strains were identified. Other possible mycotoxin-producing fungi were Penicillium (n=52) and Fusarium (n=19). Regarding total aflatoxin contamination, all samples were contaminated within a range of 1.589 to 11.854 μg/kg, and the average concentration was 6.3 μg/kg corn. Implications. The detection of mycotoxigenic fungi in the samples tested and of aflatoxins in corn highlights the importance of monitoring these fungi. Since food safety is at risk, it shows the need for methods to control these fungi and their metabolites.
Afficher plus [+] Moins [-]Determination of Mycotoxigenic Fungi and Total Aflatoxins in Stored Corn from Sites of Puebla and Tlaxcala, Mexico
2024
K. Saez-Gomez, R. Avila-Sosa, M. Huerta-Lara, F. Avelino-Flores and R. Munguia-Pérez
This paper aimed to evaluate the contamination with mycotoxigenic fungi and total aflatoxins in stored corn from different sites in Puebla and Tlaxcala, Mexico. Methodology. The study was conducted at two sites in Puebla (San Salvador El Seco and Junta Auxiliar La Resurrección) and two sites in Tlaxcala (Tlaltepango and Nativitas). A total of 80 samples of stored corn were collected. Identification of Aspergillus flavus was performed by microculture techniques and specific taxonomic keys (macromorphological and micromorphological). Then, samples of contaminated corn were selected, and aflatoxin production was confirmed using a direct solid-phase ELISA kit. A total of 25 A. flavus strains were identified. Other possible mycotoxin-producing fungi were Penicillium (n=52) and Fusarium (n=19). Regarding total aflatoxin contamination, all samples were contaminated within a range of 1.589 to 11.854 μg/kg, and the average concentration was 6.3 μg/kg corn. Implications. The detection of mycotoxigenic fungi in the samples tested and of aflatoxins in corn highlights the importance of monitoring these fungi. Since food safety is at risk, it shows the need for methods to control these fungi and their metabolites.
Afficher plus [+] Moins [-]Content of total aflatoxin, lead, and cadmium in the bovine meat and edible offal: study of their human dietary intake, health risk assessment, and molecular biomarkers
2021
Aljazzar, Ahmed | El-Ghareeb, Waleed Rizk | Darwish, Wageh Sobhy | Abdel-Raheem, Sherief M. | Ibrahim, Abdelazim M.
The objectives of the present study were first to determine the residual contents of total aflatoxins (AFTs), lead (Pb), and cadmium (Cd) in the edible tissues of the cattle reared in Al-Ahsa, Saudi Arabia. Al-Ahsa is the largest governorate in the Eastern Province of Saudi Arabia. The two main economic activities of Al-Ahsa are oil production (industrial) and agriculture. Besides, dietary intake and possible health risks for Saudi population were further calculated. In order to establish potential molecular biomarkers for xenobiotic exposure in cattle, the mRNA expression of xenobiotic-metabolizing enzymes (XMEs) including cytochrome P450 (CYP) 1A1, NAD(P)H dehydrogenase [quinone] 1 (NQO1), metallothionein (MT) 1A, and heat shock protein (HSP) 70 was investigated in the different tissues of the cattle. The tested XMEs were selected because of their specific roles in the metabolism and detoxification of AFTs, Pb, and Cd. The obtained results revealed that the liver had significantly the highest AFT content, while all examined muscle samples had no AFT residues. Consumption of the bovine liver and kidneys represents the highest source for the dietary exposure to total AFTs (0.05–0.98 μg/kg/day), Pb (0.06–0.19 mg/kg/day), and Cd (0.08–0.19 mg/kg/day) among the examined tissues. Therefore, excessive intake of such organs might pose a public health concern, particularly among children. Significant upregulation of mRNA expressions of CYP1A1, NQO1, MT1A, and HSP70 was observed in the different tissues of the cattle in comparison with the muscle. This upregulation had significant positive correlation with the accumulated AFTs, Pb, and Cd. This indicates the possible use of CYP1A1, NQO1, MT1A, and HSP70 as potential biomarkers for the exposure of the cattle to AFTs, Pb, and Cd.
Afficher plus [+] Moins [-]Toxicological Studies of Mycotoxins Using Enzymatic and Histochemical Methods
2009
Badea, Mihaela | Taus, Nicoleta | Potrovita, Monica | Moarcas, Monica
Studies concerning mycotoxins involve activities of relevant potential for furthering knowledge in the fields of toxicology and environmental analysis. Using bioanalytical methods (biosensors, histochemistry), the conducted research aims at contributing to raising the awareness of local, national, and international media in relation to the safety of obtaining and processing vegetal and animal foods, by analyzing the possible effects of aflatoxins and ochratoxins, promoting animal health, food hygiene, in view of ensuring animal and human health. The study using laboratory animals (mice) while being part of one of the current national research directions, also holds international priority, by its contribution to a better understanding of several fundamental mechanisms of life at molecular level and to the characterization of certain biological processes that appear in mycotoxicosis.
Afficher plus [+] Moins [-]The effects of diosmin on aflatoxin-induced liver and kidney damage
2017
Eraslan, Gökhan | Sarıca, Zeynep Soyer | Bayram, Latife Çakır | Tekeli, Muhammet Yasin | Kanbur, Murat | Karabacak, Mürsel
Aflatoxin is among the natural toxins that cause serious side effects on living things. Diosmin is also one of the compounds with broad pharmacological effects. In this study, the effects on the oxidant/antioxidant system of 50 mg/kg body weight/day dose of diosmin, aflatoxin (500 μg/kg body weight/day), and combined aflatoxin (500 μg/kg body weight/day) plus diosmin (50 mg/kg body weight/day) given to the stomach via catheter female adult Wistar Albino rats is examined. Forty rats were used in the experiment, and these animals were randomly allocated to four equal groups. The test phase lasted 21 days, and blood samples and tissue (liver and kidney) samples were taken after this period was over. Some biochemical parameters (glucose, triglyceride, cholesterol, blood urea nitrogen, creatinine, uric acid, lactate dehydrogenase, aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, total protein, albumin) and levels of malondialdehyde, nitric oxide, and 4-hydroxynonenal and activities of superoxide dismutase, catalase, and glutathione peroxidase were analyzed in the samples. The aflatoxin administered over the period indicated a significant increase in levels of malondialdehyde (MDA), nitric oxide (NO), and 4-hydroxynonenal (4-HNE) in all tissues and blood samples. Therewithal, the activity of antioxidant enzymes showed a change in the decreasing direction. Biochemical parameters of the group in which aflatoxin were administered alone changed unfavorably. Parallel effects were also observed in the histopathological findings of this group. The results showed that aflatoxin changed antioxidant/oxidant balance in favor of oxidant and eventually led to lipid peroxidation. Diosmin administration to aflatoxin-treated animals resulted in positive changes in antioxidant enzyme activities while the levels of MDA, NO, and 4-HNE were reduced in all tissues and blood samples examined. Diosmin alleviates the oxidative stress caused by aflatoxin. Similar improvement was observed in biochemical parameters of this group as well as in liver and kidney histopathology. No significant change was observed in the group treated with diosmin alone in terms of the parameters examined and histologic findings. As a result, diosmin may be included in compounds that can be used as a therapeutic and prophylactic agent in the event of the formation of aflatoxin exposure and poisoning in animals.
Afficher plus [+] Moins [-]Impacts of bentonite supplementation on growth, carcass traits, nutrient digestibility, and histopathology of certain organs of rabbits fed diet naturally contaminated with aflatoxin
2018
Amer, ShimaaA. | Kishawy, AsmaaT. Y. | ELseddawy, NoraM. | Abd El-Hack, MohamedE.
The present study was conducted to investigate the effect of graded levels of dietary bentonite supplementation on growth performance, carcass traits, nutrient digestibility, and histopathology of certain organs in rabbits fed a diet naturally contaminated with aflatoxin. In total, 125 weanling New Zealand White male rabbits were randomly assigned to five treatment groups each of five replicates. Treatments were as follows: T1, basal diet with no aflatoxin and no additives (positive control diet, PCD); T2, basal diet naturally contaminated with 150 ppb aflatoxin and no additives (negative control diet, NCD); T3, NCD plus 0.5% Egyptian bentonite; T4, NCD plus 1% Egyptian bentonite; and T5, NCD plus 1% Egyptian bentonite. The experiment lasted for 8 weeks. Results showed a significant decrease (P < 0.05) in the body weight and the body weight gain in the NCD, while they were improved (P < 0.05) in groups fed diets supplemented with different levels of bentonite. The relative weight of the liver and kidneys were higher in the NCD, while the liver weight was relatively high in the group fed NCD supplemented with 0.5% bentonite, and it was not significant in other bentonite-supplemented groups. Bentonite supplementation improved the digestibility coefficients of various nutrients. Bentonite addition decreased the histopathological lesions in liver, kidney, and intestine caused by aflatoxin-infected diets. In conclusion, bentonite supplementation overcame the negative effect of aflatoxin, enhanced growth performance traits, decreased the relative weights of the liver and the kidney which are usually increased by aflatoxin, caused significant improvement in nutrients’ digestibility, and decreased the histopathological lesions caused by aflatoxin-infected diets. The level of 2% bentonite is recommended for ameliorating the aflatoxin effects.
Afficher plus [+] Moins [-]Prevalence of mycotoxins in feed and feed ingredients between 2015 and 2017 in Taiwan
2019
Yang, Ching-Kuo | Cheng, Yeong-Hsiang | Tsai, Wan-Ting | Liao, Rou-Wan | Zhang, Jiasheng | Chien, Wan-Chu | Jhang, Jia-Cin | Yu, Yu-Hsiang
Contamination of feed by mycotoxins is a global epidemic that has a sizeable impact on animal health and causes economic losses. Mycotoxins, including aflatoxins (AFs), zearalenone (ZEN), fumonisins (FUMs), deoxynivalenol (DON), and ochratoxin A (OTA), lead to acute and chronic adverse effects in pigs. Animal feed and feed ingredients are commonly contaminated by one or more mycotoxins worldwide; however, the prevalence of mycotoxin contamination in feed and feed ingredients in Taiwan remains unclear. A total of 820 cornmeal and corn-based swine feed (pregnancy and nursery diets) samples provided by feed and animal producers were analyzed using the enzyme-linked immunosorbent assay method between January 2015 and December 2017 to determine the presence of mycotoxins. The results revealed that the most prevalent mycotoxin in Taiwan was DON, with 91.4% of positive samples between 2015 and 2017, followed by ZEN, AFs, and FUMs, with 70.2%, 58.0%, and 50.4% of positive samples, respectively. A similar prevalence of mycotoxins was observed in cornmeal and corn-based swine feed. Furthermore, 7.7% of the analyzed feed samples contained one mycotoxin, and 91.3% contained multiple mycotoxins. DON was the most prevalent mycotoxin in cornmeal and corn-based swine feed in Taiwan. Moreover, a high incidence of contamination by multiple mycotoxins was observed in swine feed. Awareness of mycotoxin presence in feed and development of mycotoxin detoxification strategies are unmet needs.
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