Occurrence of some mycotoxins (aflatoxin, ochratoxin A, citrinin, zearalenone and vomitoxin) in various Egyptian feeds

Mycotoxin contamination in the Arab world: Highlighting the main knowledge gaps and the current legislation

Since the discovery of aflatoxins in the 1960s, knowledge in the mycotoxin research field has increased dramatically. Hundreds of review articles have been published summarizing many different aspects, including mycotoxin contamination per country or region. However, mycotoxin contamination in the Arab world, which includes 22 countries in Africa and Asia, has not yet been specifically reviewed. To this end, the contamination of mycotoxins in the Arab world was reviewed not only to profile the pervasiveness of the problem in this region but also to identify the main knowledge gaps imperiling the safety of food and feed in the future. To the best of our knowledge, 306 (non-)indexed publications in English, Arabic, or French were published from 1977 to 2021, focusing on the natural occurrence of mycotoxins in matrices of 14 different categories. Characteristic factors (e.g., detected mycotoxins, concentrations, and detection methods) were extracted, processed, and visualized. The main results are summarized as follows: (i) research on mycotoxin contamination has increased over the years. However, the accumulated data on their occurrences are scarce to non-existent in some countries; (ii) the state-of-the-art technologies on mycotoxin detection are not broadly implemented neither are contemporary multi-mycotoxin detection strategies, thus showing a need for capacity-building initiatives; and (iii) mycotoxin profiles differ among food and feed categories, as well as between human biofluids. Furthermore, the present work highlights contemporary legislation in the Arab countries and provides future perspectives to mitigate mycotoxins, enhance food and feed safety, and protect the consumer public. Concluding, research initiatives to boost mycotoxin research among Arab countries are strongly recommended.

Mycotoxin Detection in Maize, Commercial Feed, and Raw Dairy Milk Samples from Assiut City, Egypt

This survey was conducted to investigate the contamination by multiple mycotoxins, aflatoxins (AFB₁, AFB₂, AFG₁, and AFG₂), ochratoxin A (OTA), and zearalenone (ZEA) in 61 samples of maize and 17 commercial animal feed samples, and of aflatoxin M₁ (AFM₁) in raw dairy milk samples (n = 20) collected from Assiut City in Upper Egypt. Multi-mycotoxin immunoaffinity columns were used for samples cleanup and mycotoxin purification. An HPLC–FLD system with an on-line post-column photochemical derivatization was used for the detection of the target toxins. AFB₁ was detected in both maize (n = 15) and feed (n = 8), with only one maize sample presenting a concentration above the maximum permissible level set by the Egyptian authorities. AFB₂ was observed in six maize samples and in one feed sample, with a maximum value of 0.5 μg/kg. ZEA was detected only in feed samples (n = 4), with a maximum value of 3.5 μg/kg, while OTA, AFG₁, and AFG₂ were under the limits of detection. For milk, all the analyzed samples (100%) were contaminated with AFM₁, and 14 samples (70%) presented concentrations above the maximum permissible level in the European Union (EU) (0.05 μg/kg). The concentrations ranged from 0.02 μg/kg to 0.19 μg/kg, except that of one sample, which was under the limit of quantification. The contamination rates in maize and animal feeds are not alarming. In contrast, the consumption of dairy milk samples in Assiut City may pose public health hazards, as AFM₁ levels were found to exceed the international permissible limits. Further surveys are highly recommended in order to establish a database for mycotoxin occurrence in Egypt to minimize the possible health risks in animals and humans.

Levels of zearalenone and its metabolites in sun-dried kapenta fish and water of Lake Kariba in Zambia - A preliminary study

Contamination of food with mycotoxins and the associated possibilities of human intoxication is a serious problem in Africa. One of the most widespread mycotoxins is zearalenone (ZEN), which usually occurs in food of vegetable origin. On the other hand, information about ZEN in products of animal origin in African countries is extremely scanty. During the present study, levels of ZEN and its analogs: α-zearalenol (α-ZEL) and β-zearalenol (β-ZEL) were measured by high performance liquid chromatography (HPLC) with fluorescence detection in sun-dried kapenta fish - traditional Zambian food, as well as in the water of Lake Kariba - the main source of kapenta fish in Zambia. This study revealed that levels of ZEN in sun-dried kapenta fish fluctuated from 27.2 μg·kg^-1 to 53.9 μg·kg^-1, whereas the contamination of water from Lake Kariba with ZEN is rather minimally similar to the content of ZEN analogs in both kapenta fish and water. The obtained results have shown that sun-dried kapenta fish of Lake Kariba contain ZEN and may contribute to the exposure of consumers to this substance.

Occurrence of multiple mycotoxins and other fungal metabolites in animal feed and maize samples from Egypt using LC-MS/MS

BACKGROUND

The present study aimed to investigate the occurrence of multiple toxic fungal and bacterial metabolites in 156 animal feed (n = 77) and maize (n = 79) samples collected from three regions in Upper Egypt. The target analytes were quantified using the 'dilute and shoot' approach, followed by a liquid chromatography tandem mass spectrometry analysis.

RESULTS

In total, 115 fungal and bacterial metabolites were detected in both matrices, including the regulated mycotoxins in the European Union, in addition to the modified forms such as deoxynivalenol-3-glucosid. Furthermore, some Fusarium, Alternaria, Aspergillus and Penicillum metabolites beside other fungal and bacterial metabolites were detected for the first time in Egypt. All of the samples were contaminated with at least four toxins. On average, 26 different metabolites were detected per sample with a trend of more metabolites in feed than in maize. The maximum number of analytes observed per samples was 54 analytes at maximum concentrations ranging from 0.04 µg kg^-1 for tentoxin to 25 040 µg kg^-1 for kojic acid.

CONCLUSION

According to the international standards, the contamination rates in the investigated regions were not alarming, except for AFB1 in maize. The necessity of further and continuous monitoring is highly recommended to establish a database for mycotoxin occurrence. © 2017 Society of Chemical Industry.

Unraveling the mechanisms involved in zearalenone-mediated toxicity in permanent fish cell cultures

The world-wide occurrence of zearalenone (ZEN) as a contaminant in feed for farm animals and fish requires the evaluation of toxicity mechanisms of action of ZEN. The present study investigates possible metabolization of ZEN in fish cell lines suggesting that mainly glucuronidation takes place. It demonstrates that concentrations up to 20,000 ng ml(-1) ZEN are capable of influencing cell viability in permanent fish cell cultures in a dose-response manner with different response patterns between the five tested cell lines, whereby lysosomes appeared to be the main target of ZEN. ZEN toxicity is often discussed in the context of oxidative stress. Our study shows a biphasic response of the cell lines when reactive oxygen species (ROS) production is monitored. Damage in cells was observed by measuring lipid peroxidation, DNA strand breaks, and alterations of intracellular glutathione levels. Metabolization of ZEN, especially at concentrations above 7500 ng ml(-1) ZEN, does not prevent cytotoxicity. ZEN as an estrogenic compound may involve processes mediated by binding to estrogen receptors (ER). Since one cell line showed no detectable expression of ER, an ER-mediated pathway seems to be unlikely in these cells. This confirms a lysosomal pathway as a main target of ZEN in fish cells.

Case report evidence of relationships between hepatocellular carcinoma and ochratoxicosis

Purpose

The incidence of Hepatocellular carcinoma (HCC) is on the rise, but what is causing that trend has remained a mystery. Mycotoxins are almost entirely ignored health problems, and sometimes actually naively belittled in advanced medical care. Ochratoxin A (OTA) is one of the most abundant food contaminating mycotoxins worldwide that is carcinogenic, but no studies have evaluated its levels in HCC patients. Therefore, this study was designed to monitor the presence of OTA in the serum of HCC patients and to quantify the strength of the association between OTA and HCC.

Methods

We conducted a case control-based study on 61 participants. Thirty-nine were HCC cases identified between 2010 and 2012 and individually matched by age, sex, residence and date of recruitment to 22 healthy controls. Serum OTA and alpha-fetoprotein levels were measured by using high-performance liquid chromatography (HPLC) and enzyme-linked immunosorbent assay, respectively.

Results

HPLC analysis of 61 serum samples indicated that the highest incidence of elevated OTA was found in the HCC group and was 5-fold higher than in the control group. The concentration of OTA in the HCC group ranged between 0.129 and 10.93 ng/mL with a mean value±SD of 1.1±0.3 ng/mL, while in the normal group it ranged between 0.005 and 0.50 ng/mL with a mean value±SD of 0.201±0.02 ng/mL. The odds ratio for HCC patients presenting OTA levels above the cut-off of 0.207 (calculated by the receiver operating characteristic curve) was 9.78 (95% confidence interval = 2.9095–32.9816, P = 0.0002) with respect to normal controls, suggesting that HCC is 9.8 times as frequent in the exposed group to OTA.

Conclusion

Our results reveal a strong association between the presence of OTA and HCC, which may offer a coherent explanation for much of the descriptive epidemiology of HCC and suggest new avenues for analytical research.

Assessment of aflatoxin contamination of maize, peanut meal and poultry feed mixtures from different agroecological zones in Cameroon

Mycotoxins affect poultry production by being present in the feed and directly causing a negative impact on bird performance. Carry-over rates of mycotoxins in animal products are, in general, small (except for aflatoxins in milk and eggs) therefore representing a small source of mycotoxins for humans. Mycotoxins present directly in human food represent a much higher risk. The contamination of poultry feed by aflatoxins was determined as a first assessment of this risk in Cameroon. A total of 201 samples of maize, peanut meal, broiler and layer feeds were collected directly at poultry farms, poultry production sites and poultry feed dealers in three agroecological zones (AEZs) of Cameroon and analyzed for moisture content and aflatoxin levels. The results indicate that the mean of the moisture content of maize (14.1%) was significantly (P < 0.05) higher than all other commodities (10.0%–12.7%). Approximately 9% of maize samples were positive for aflatoxin, with concentrations overall ranging from <2 to 42 µg/kg. Most of the samples of peanut meal (100%), broiler (93.3%) and layer feeds (83.0%) were positive with concentrations of positive samples ranging from 39 to 950 µg/kg for peanut meal, 2 to 52 µg/kg for broiler feed and 2 to 23 µg/kg for layer feed. The aflatoxin content of layer feed did not vary by AEZ, while the highest (16.8 µg/kg) and the lowest (8.2 µg/kg) aflatoxin content of broiler feed were respectively recorded in Western High Plateau and in Rainforest agroecological zones. These results suggest that peanut meal is likely to be a high risk feed, and further investigation is needed to guide promotion of safe feeds for poultry in Cameroon.

Mycotoxin levels and incidence of mould in Turkish rice

One hundred unpackaged rice samples, each weighing 500 g, were randomly collected at retail stores and open markets in the largest rice growing area (Thrace) in Turkey and analysed for mould counts, predominant mould genera, moisture content and mycotoxin levels. Mould counts ranged from 1.0 × 10(1) to 1.5 × 10(4) cfu/g in 70 of 100 samples, and the correlation between moisture content and mould count was significant (p ≤ 0.05). Aspergillus spp. and Penicillium spp., potential mycotoxin producers, were the dominant moulds. In one area from which samples were collected, the mycotoxin content of rice was found to be positively correlated with moisture content; samples with higher moisture also contained higher numbers of moulds. The levels of total aflatoxins, aflatoxin B1 and ochratoxin A were higher than the maximum tolerable limits (4, 2 and 3 μg/kg, according to the EC Regulation and the Turkish Food Codex) for 32, 14 and 30 of 100 rice samples, respectively. This is the first comprehensive report of ochratoxin A levels in rice grown in Thrace, Turkey.

Ochratoxin A: The Continuing Enigma

The mycotoxin ochratoxin A (OTA) has been linked to the genesis of several disease states in both animals and humans. It has been described as nephrotoxic, carcinogenic, teratogenic, immunotoxic, and hepatotoxic in laboratory and domestic animals, as well as being thought to be the probable causal agent in the development of nephropathies (Balkan Endemic Nephropathy, BEN and Chronic Interstitial Nephropathy, CIN) and urothelial tumors in humans. As a result, several international agencies are currently attempting to define safe legal limits for OTA concentration in foodstuffs (e.g., grain, meat, wine, and coffee), in processed foods, and in animal fodder. In order to achieve this goal, an accurate risk assessment of OTA toxicity including mechanistic and epidemiological studies must be carried out. Ochratoxin has been suggested by various researchers to mediate its toxic effects via induction of apoptosis, disruption of mitochondrial respiration and/or the cytoskeleton, or, indeed, via the generation of DNA adducts. Thus, it is still unclear if the predominant mechanism is of a genotoxic or an epigenetic nature. One aspect that is clear, however, is that the toxicity of OTA is subject to and characterized by large species- and sex-specific differences, as well as an apparently strict structure-activity relationship. These considerations could be crucial in the investigation of OTA-mediated toxicity. Furthermore, the use of appropriate in vivo and in vitro model systems appears to be vital in the generation of relevant experimental data. The intention of this review is to collate and discuss the currently available data on OTA-mediated toxicity with particular focus on their relevance for the in vivo situation, and also to suggest possible future strategies for unlocking the secrets of ochratoxin A.

Incidence of ochratoxin A in rice and dried fruits from Rabat and Salé area, Morocco

One hundred samples of dried fruits (20 dried raisins, 20 walnuts, 20 peanuts, 20 dried figs and 20 pistachios) and 20 samples of rice purchased from retail shops in the Rabat and Salé area in Morocco were analysed for ochratoxin A (OTA) by immunoaffinity clean-up (IAC) and liquid chromatography (LC) with fluorescence detection. The limit of quantification (LOQ) (S/N = 10:1) of OTA was 0.02 ng g(-1) in rice, 0.03 ng g(-1) in pistachio, peanut and walnut, and 0.03 ng g(-1) in dried raisins and dried figs. The incidences of occurrence of OTA in dried raisins, walnuts, peanuts, dried figs and rice were 30, 35, 25, 65 and 90%, respectively. Analytical results showed that pistachio samples contained no detectable OTA, but concentrations ranged from 0.02 +/- 0.01 to 32.4 +/- 2.10 ng g(-1) in rice, from 0.10 +/- 0.05 to 2.36 +/- 0.75 in peanut, from 0.03 +/- 0.01 to 1.42 +/- 0.45 in dried figs, from 0.05 +/- 0.02 to 4.95 +/- 0.02 in dried raisins, and from 0.04 +/- 0.01 to 0.23 +/- 0.05 in walnuts. The results also showed that 15% of the total number of rice samples analysed exceeded the 2002 regulatory limit set by European Union regulations for cereals. This is the first report on the occurrence of OTA in dried fruits and rice available in Morocco.

Co-occurrence of aflatoxin B1, fumonisin B1, ochratoxin A and zearalenone in cereals and peanuts from Côte d’Ivoire

This survey examined 30 samples of rice (n = 10), maize (n = 10) and peanuts (n = 10) from Côte d'Ivoire for aflatoxin B1, fumonisin B1 and zearalenone using immunoassays, and ochratoxin A using a validated HPLC method with fluorescence detection. In Côte d'Ivoire, as in other countries, several mycotoxins are present in the same commodities. These mycotoxins are from different structural families: aflatoxin B1, fumonisin B1, zearalenone and ochratoxin A, normally produced by fungal species from Aspergillus, Penicillium and Fusarium genera. Some samples contained four mycotoxins (86%). Four peanuts samples did not show ochratoxin A (14%), whereas they contained aflatoxin B1 concentrations above the EU regulatory limits. Concentrations of ochratoxin A, zearalenone and fumonisin B1 were low and may not cause problems per se; however, fears remain that the tolerable daily intake may be exceeded due to eating habits and synergistic effects could be important with the combination of several mycotoxins. Investigations in this direction are underway, together with isolation and characterization of the fungal species involved.

Mycotoxins in poultry feed in Kuwait

A survey was conducted at a poultry feed production unit in Kuwait for mycotoxin contamination in the samples of yellow maize, soybean meal, wheat bran used as raw material and the poultry feed prepared for broiler starter, broiler finisher, and layer mash. Individual aflatoxins were determined by high-pressure liquid chromatography after immunoaffinity column purification. Repeated analysis revealed average aflatoxin concentration in maize at 0.27 ppb (range 0 to 1.69 ppb), soybean meal at 0.20 ppb (range 0 to 1.27 ppb), wheat bran at 0.15 ppb (range 0 to 1.07 ppb), prepared poultry feed for broiler starter at 0.48 ppb (range 0 to 3.26 ppb), broiler finisher at 0.39 ppb (range 0 to 1.05 ppb), and layer mash at 0.21 ppb (range 0 to 1.30 ppb). Other mycotoxins (ochratoxin, fumonisin, deoxynivalenol (DON), and zearalenone), were detected by quantitative enzyme-linked immunosorbent assay. The average levels of ochratoxin A ranged from 4.6 to 9.6 ppb, fumonisin from 1.4 to 3.2 ppm, DON from 0.17 to 0.29 ppm, and zearalenone from 46.4 to 67.6 ppb in various commodities and prepared feed samples. The study revealed the coexistence of determined mycotoxins, although their concentrations in general were found to be lower than the permissible levels, wherever defined, for the poultry feed.

Occurrence and daily intake of ochratoxin A of organic and non-organic rice and rice products

Ochratoxin A (OTA) was extracted from 84 rice samples and rice products by using accelerated solvent extraction (ASE) and analysed with liquid chromatography coupled with fluorescence detection. Samples were collected from rice cultivars, local markets and supermarkets; 64 were of non-organic and 20 of organic production. 7.8% of non-organic samples had OTA levels from 4.3 to 27.3 microg/kg and in 30% of organic samples was detected the presence of this mycotoxin varying from 1.0 to 7.1 microg/kg. OTA presence was confirmed by methyl-ester derivatization. Rice and rice products labelled with denomination of origin (DO) were not detected OTA due to the fact that its production has implemented food safety measures such as good agricultural practices (GAPs), good manufacturing practices (GMPs), and the hazard analysis and critical control point (HACCP) system. Estimated daily intake of OTA was 0.17 ng/kg b.w./day. This value reflects that the analysed samples have a minimal contribution to toxicological risk.

Study of ochratoxin A as an environmental risk that causes renal injury in breast-fed Egyptian infants

Ochratoxin A (OTA) constitutes a real human threat. Its presence in human milk has previously been reported in different countries. This study is the first Egyptian report on the presence of OTA in both mothers' milk and infants' sera, addressing its correlation with infants' kidney functions, which was not previously addressed in the literature. Fifty healthy breast-lactating mothers and their infants who were exclusively breast-fed for at least 4 months were included. All of them were subjected to a thorough laboratory evaluation including determination of OTA concentration by high-performance liquid chromatography. Thirty-six mothers (72%) and their infants had been contaminated with OTA. Univariate analysis showed that the presence of OTA was associated with significantly higher levels of urinary beta2 microglobulin and microalbuminuria. Multivariate logistic regression analysis showed that there was a significant correlation between a higher OTA level in infants' sera and the degree of microalbuminuria. Mothers and their infants in our locality are exposed to a high OTA contamination rate (72%). To establish the role of OTA in causation of future renal dysfunction for infants, large controlled studies are warranted.

Seed-borne fungi and ochratoxin A contamination of dry beans (Phaseolus vulgaris L.) in the Republic of Croatia

The study was designed to identify seed-borne fungi on bean (Phaseolus vulgaris L.) crops grown in 13 counties of the Republic of Croatia and their association with ochratoxin A (OTA) production. Bean samples (N=45) were collected in Croatia in 2001 shortly after the harvest and were stored at -20 degrees C for mycological and mycotoxin analyses. The most common fungi isolated were Cladosporium spp. (98%) Alternaria spp. (75%), Aspergillus spp. (73%), Rhizopus spp. (73%), Penicillium spp. (69%), Fusarium spp. (38%), Botrytis spp. (27%), Trichothecium spp. (24%), and Chaetomium spp. (18%). OTA was found only in samples contaminated with Penicillium and Aspergillus spp. Using HPLC (detection limit 0.25 microg/kg), OTA was found in 17 out of 45 samples (38%), and the mean concentration in positive samples was 0.41+/-0.21 microg OTA/kg. Beans from south Croatia (Adriatic coast) were OTA-free and the least mould-infected, while the mean OTA concentration and mould infection of samples from other regions were similar. The OTA contamination of beans in our country is low. Although beans are not severely contaminated with OTA, their consumption may contribute to the exposure to OTA from other commodities.

Oxidative damage to lipids and proteins induced by aflatoxin B(1) in fish (Labeo rohita)-protective role of Amrita Bindu

In the present study, fish (Labeo rohita) were treated with a single intraperitoneal administration of aflatoxin B(1) (AFB(1)) (100μg/100gBW). The resultant oxidative damage to lipids (measured as conjugated diene and lipid peroxidation (LPO)) and proteins (protein carbonyl) in liver, kidney and brain at the end of 3rd and 6th day was assessed. Our results showed that AFB(1) induced a significant increase in conjugated diene formation and LPO not only in liver but also in kidney and brain. A parallel increase in protein carbonyl level was observed in these tissues. When 1:1 mixture of 20% solution of Amrita Bindu (a salt-spice-herbal mixture based on Indian system of medicine) was co-administered along with 100μg AFB(1), the AFB(1) induced increase in conjugated diene, LPO and protein carbonylation were minimised to a greater extent. These results led to conclusion that (i) AFB(1) not only induces oxidative damage to the primary target organ-liver in L. rohita, but also in kidney and brain, (ii) co-administration of Amrita Bindu confers protection to lipids and protein against the AFB(1) induced oxidative damage in all the three tissues.

Effect of raising dietary protein, amino acids and/or energy levels as an attempt to alleviate severity of the chronic aflatoxicosis by broiler chicks. 2. Biochemical characteristics

Aflatoxin caused some reduction in moisture contents of chest and liver, lipids of thigh and blood, blood glucose, muscular protein and GOT in liver. It led also to increase of moisture contents of thigh and kidneys; chest lipids; blood cholesterol; protein of liver, kidneys and blood and blood creatinine. The different supplements used herein led to increasing moisture of muscles, liver and kidneys (except on oil addition); lipids of muscles (except of chest on high energy diet) and blood (except on amino acids-supplemented diet); blood cholesterol (except on high energy one); protein of thigh (except on high protein one) and blood (except on high energy or amino acids diets) and liver GPT (except on high energy diet). The additives led also to low blood glucose; protein of chest (except on high energy), liver, and kidneys; blood creatinine; liver GOT (particularly with high energy or amino acids); plasma GOT (on high amino acids) and plasma GPT. The 2-week withdrawal period led to low moisture contents of muscles and kidneys of most treatments, although they continued higher than in the control for chest, liver and kidneys. It increased blood glucose and cholesterol with continuous higher lipid content of muscles and blood and blood cholesterol than in the control. It led to elevated protein content of muscles, liver (except on the control or supplements mixture), kidneys (on the aflatoxin alone or with the amino acids) and blood (except on the control or aflatoxin alone or with high protein) and blood creatinine (except on the control or on the high energy or the supplements mixture).(ABSTRACT TRUNCATED AT 250 WORDS)

Citrinin

Citrinin, a nephrotoxic mycotoxin, has been of growing importance also for the "International Agency for Research on Cancer", ever since its presumable role in the occurrence of Balcan endemic nephropathy (BEN) was discussed at the congress on "Mycotoxins, Endemic Nepthropathy and Urinary Tract Tumours" held in Lyon in June 1991 (12). In late 1991, citrinin was therefore also included in the list of toxins to be examined by the screening subcommittees on natural toxins of the International Live Science Institute, European Branch.