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  • MDPI AG  (6)
  • Tangni, Emmanuel K.  (6)
  • 1
    Online Resource
    Online Resource
    Organisation of Multi-Mycotoxin Proficiency Tests: Evaluation of the Performances of the Laboratories Using the Triple A Rating Approach
    MDPI AG ; 2021
    In:  Toxins Vol. 13, No. 9 ( 2021-08-24), p. 591-
    Details
    In: Toxins, MDPI AG, Vol. 13, No. 9 ( 2021-08-24), p. 591-
    Abstract: In accordance with the International Standard Organization ISO 17043, two proficiency tests (PTs) for the simultaneous determination of aflatoxins (AFB1, AFB2, AFG1, AFG2); deoxynivalenol; fumonisins FB1, FB2, and B3; ochratoxin A, the T-2 toxin; and the HT-2 toxin were conducted in 2019 and 2020 using cornflakes and rusk flours that were prepared in house. The homogeneity and the stability of these materials were verified according to the criteria laid down in ISO 13528 using randomly selected samples. Most of the targeted toxins were found to be homogenously distributed in both materials with no significant changes during the timescale of the PTs. Next, the materials were distributed to approximately 25 participating laboratories from Europe, Canada, and the United States. The obtained datasets were computed using robust statistics. The outliers were checked and removed, and the toxin concentrations were assigned as the consensus value of the results of the participants at Horwitz ratios 〈 1.2. The z scores were generated for all mycotoxins, and the results were pooled to calculate the relative sum of squared z scores (SZ2) indexes and were clustered according to the triple A rating. Overall, at least 80% of the participating laboratories achieved good and acceptable performances. The most frequent categories assigned to good performances (SZ2 ≤ 2) were AAA (51%) and BAA (13%). Clusters of BBA + CBA (6%) included laboratories reporting acceptable z scores 〈 90% of the total z scores for less than 90% or 50% of the mycotoxins targeted in the 2 matrices. The triple A rating seems to be appropriate in evaluating the performances of laboratories involved in multi-mycotoxin analyses. Accredited and non-accredited analytical methods achieved good and acceptable performances.
    Type of Medium: Online Resource
    ISSN: 2072-6651
    URL: Article
    DOI: 10.3390/toxins13090591
    Language: English
    Publisher: MDPI AG
    Publication Date: 2021
    detail.hit.zdb_id: 2518395-3
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  • 2
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    Online Resource
    A Study of Carry-Over and Histopathological Effects after Chronic Dietary Intake of Citrinin in Pigs, Broiler Chickens and Laying Hens
    MDPI AG ; 2020
    In:  Toxins Vol. 12, No. 11 ( 2020-11-16), p. 719-
    Details
    In: Toxins, MDPI AG, Vol. 12, No. 11 ( 2020-11-16), p. 719-
    Abstract: Citrinin (CIT) is a polyketide mycotoxin occurring in a variety of food and feedstuff, among which cereal grains are the most important contaminated source. Pigs and poultry are important livestock animals frequently exposed to mycotoxins, including CIT. Concerns are rising related to the toxic, and especially the potential nephrotoxic, properties of CIT. The purpose of this study was to clarify the histopathological effects on kidneys, liver, jejunum and duodenum of pigs, broiler chickens and laying hens receiving CIT contaminated feed. During 3 weeks, pigs (n = 16) were exposed to feed containing 1 mg CIT/kg feed or to control feed (n = 4), while 2 groups of broiler chickens and laying hens (n = 8 per group) received 0.1 mg CIT/kg feed (lower dose group) and 3 or 3.5 mg CIT/kg feed (higher dose group), respectively, or control feed (n = 4). CIT concentrations were quantified in plasma, kidneys, liver, muscle and eggs using a validated ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) method. Kidneys, liver, duodenum and jejunum were evaluated histologically using light microscopy, while the kidneys were further examined using transmission electron microscopy (TEM). Histopathology did not reveal major abnormalities at the given contamination levels. However, a significant increase of swollen and degenerated mitochondria in renal cortical cells from all test groups were observed (p 〈 0.05). These observations could be related to oxidative stress, which is the major mechanism of CIT toxicity. Residues of CIT were detected in all collected tissues, except for muscle and egg white from layers in the lowest dose group, and egg white from layers in the highest dose group. CIT concentrations in plasma ranged between 0.1 (laying hens in lower dose group) and 20.8 ng/mL (pigs). In tissues, CIT concentrations ranged from 0.6 (muscle) to 20.3 µg/kg (liver) in pigs, while concentrations in chickens ranged from 0.1 (muscle) to 70.2 µg/kg (liver). Carry-over ratios from feed to edible tissues were between 0.1 and 2% in pigs, and between 0.1 and 6.9% in chickens, suggesting a low contribution of pig and poultry tissue-derived products towards the total dietary CIT intake for humans.
    Type of Medium: Online Resource
    ISSN: 2072-6651
    URL: Article
    DOI: 10.3390/toxins12110719
    Language: English
    Publisher: MDPI AG
    Publication Date: 2020
    detail.hit.zdb_id: 2518395-3
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  • 3
    Online Resource
    Online Resource
    Citrinin Determination in Food and Food Supplements by LC-MS/MS: Development and Use of Reference Materials in an International Collaborative Study
    MDPI AG ; 2021
    In:  Toxins Vol. 13, No. 4 ( 2021-03-30), p. 245-
    Details
    In: Toxins, MDPI AG, Vol. 13, No. 4 ( 2021-03-30), p. 245-
    Abstract: The development of incurred reference materials containing citrinin (CIT) and their successful application in a method validation study (MVS) in order to harmonize CIT determination in food and food supplements are demonstrated. CIT-contaminated materials made of red yeast rice (RYR), wheat flour, and Ginkgo biloba leaves (GBL), as well as food supplements made of red yeast rice (FS-RYR) and Ginkgo biloba leaves (FS-GBL), were manufactured in-house via fungal cultivation on collected raw materials. The homogeneity and stability from randomly selected containers were verified according to the ISO 13528. CIT was found to be homogenously distributed and stable in all contaminated materials, with no significant degradation during the timescale of the MVS when storage was performed up to +4 °C. Next, an MVS was organized with eighteen international laboratories using the provided standard operating procedure and 12 test materials, including three RYRs (blank, 〈 50 µg/kg, 〈 2000 µg/kg), two wheat flours (blank, 〈 50 µg/kg), two GBL powders (blank, 〈 50 µg/kg), three FS-RYRs (blank, 〈 50 µg/kg, 〈 2000 µg/kg), and two FS-GBLs (blank, 〈 50 µg/kg). The results of seven CIT-incurred materials showed acceptable within-laboratory precision (RSDr) varying from 6.4% to 14.6% and between-laboratory precision (RSDR) varying from 10.2% to 37.3%. Evidenced by HorRat values 〈 2.0, the results of the collaborative trial demonstrated that the applied analytical method could be standardized. Furthermore, the appropriateness of producing CIT reference materials is an important step towards food and feed quality control systems and the organization of proficiency tests.
    Type of Medium: Online Resource
    ISSN: 2072-6651
    URL: Article
    DOI: 10.3390/toxins13040245
    Language: English
    Publisher: MDPI AG
    Publication Date: 2021
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  • 4
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    Analysis of Patulin in Apple Products Marketed in Belgium: Intra-Laboratory Validation Study and Occurrence
    MDPI AG ; 2023
    In:  Toxins Vol. 15, No. 6 ( 2023-05-30), p. 368-
    Details
    In: Toxins, MDPI AG, Vol. 15, No. 6 ( 2023-05-30), p. 368-
    Abstract: Apple and apple derivatives (e.g., juices, puree) are the most important foodstuffs contaminated with patulin (PAT) in the human diet. To routinely monitor these foodstuffs and ensure that the PAT levels are below the maximum permitted levels, a method using liquid chromatography combined with tandem mass spectrometry (LC-MS/MS) has been developed. Afterwards, the method was successfully validated, reaching quantification limits of 1.2 μg/L for apple juice and cider, and 2.1 μg/kg for puree. Recovery experiments were performed with samples fortified with PAT in the range of 25–75 μg/L for juice/cider and 25–75 μg/kg for puree. The results show overall average recovery rates of 85% (RSDr = 13.1%) and 86% (RSDr = 2.6%) with maximum extended uncertainty (Umax, k = 2) of 34 and 35% for apple juice/cider and puree, respectively. Next, the validated method was applied to 103 juices, 42 purees and 10 ciders purchased on the Belgian market in 2021. PAT was not found in the cider samples, but it was present in 54.4% of the tested apple juices (up to 191.1 μg/L) and 7.1% of the puree samples (up to 35.9 μg/kg). When comparing the results to the maximum levels set by Regulation EC n° 1881/2006 (i.e., 50 μg/L for juices and 25 μg/kg for puree for adults, and 10 μg/kg for infants and young children), exceedances were observed in five apple juices and one puree sample, for infants and young children. Using these data, a potential risk assessment for consumers can be suggested, and it is found that the quality of apple juices and purees sold in Belgium needs further regular surveillance.
    Type of Medium: Online Resource
    ISSN: 2072-6651
    URL: Article
    DOI: 10.3390/toxins15060368
    Language: English
    Publisher: MDPI AG
    Publication Date: 2023
    detail.hit.zdb_id: 2518395-3
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  • 5
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    Development of a QuEChERS-Based UHPLC-MS/MS Method for Simultaneous Determination of Six Alternaria Toxins in Grapes
    MDPI AG ; 2019
    In:  Toxins Vol. 11, No. 2 ( 2019-02-01), p. 87-
    Details
    In: Toxins, MDPI AG, Vol. 11, No. 2 ( 2019-02-01), p. 87-
    Abstract: A simple and reliable analytical method for the simultaneous determination of alternariol (AOH), altenuene (ALT), tentoxin (TEN), altenusin (ALS), tenuazonic acid (TeA), and alternariol monomethyl ether (AME) in grapes was developed by ultra-high-performance liquid chromatography–tandem mass spectrometry (UHPLC-MS/MS). A modified QuEChERS (quick, easy, cheap, effective, rugged, and safe) procedure with the extraction by acetonitrile and purification by sodium chloride (0.5 g) and anhydrous magnesium sulfate (0.5 g) was established to recover the six Alternaria toxins. After validation by determining the linearity (R2 〉 0.99), recovery (77.8–101.6%), sensitivity (limit of detection in the range of 0.03–0.21 μg kg−1, and limit of quantification in the range of 0.09–0.48 μg kg−1), and precision (relative standard deviation (RSD) ≤ 12.9%), the analytical method was successfully applied to reveal the contamination state of Alternaria toxins in grapes. Among 56 grape samples, 40 (incidence of 71.4%) were contaminated with Alternaria toxins. TEN was the most frequently found mycotoxin (37.5%), with a concentration range of 0.10–1.64 μg kg−1, followed by TeA (28.6%) and AOH (26.8%). ALT (10.7%), AME (3.6%), and ALS (5.4%) were also detected in some samples. To the best of our knowledge, this is the first report about the Alternaria toxins contamination in grapes in China.
    Type of Medium: Online Resource
    ISSN: 2072-6651
    URL: Article
    DOI: 10.3390/toxins11020087
    Language: English
    Publisher: MDPI AG
    Publication Date: 2019
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  • 6
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    Production of Alternaria Toxins in Yellow Peach (Amygdalus persica) upon Artificial Inoculation with Alternaria alternate
    MDPI AG ; 2021
    In:  Toxins Vol. 13, No. 9 ( 2021-09-15), p. 656-
    Details
    In: Toxins, MDPI AG, Vol. 13, No. 9 ( 2021-09-15), p. 656-
    Abstract: The yellow peach (Amygdalus persica), an important fruit in China, is highly susceptible to infection by Alternaria sp., leading to potential health risks and economic losses. In the current study, firstly, yellow peaches were artificially inoculated with Alternariaalternate. Then, the fruits were stored at 4 °C and 28 °C to simulate the current storage conditions that consumers use, and the Alternaria toxins (ATs) contents from different parts of the fruits were analyzed via ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS). The results showed that the growth of A. alternate and the ATs production were dramatically affected by the storage temperature. At 28 °C, the fungi grew rapidly and the lesion diameter reached about 4.0 cm within 15 days of inoculation, while, at 4 °C, the fungal growth was noticeably inhibited, with no significant change in the lesion diameter. To our surprise, high contents of ATs were produced under both storage conditions even though the fungal growth was suppressed. With an increase in the incubation time, the amounts of ATs showed a steady tendency to increase in most cases. Remarkably, alternariol monomethyl ether (AME), alternariol (AOH), and tenuazonic acid (TeA) were detected in the rotten tissue and also in the surrounding tissue, while a large amount of TeA could also be found in the healthy tissue. To the best of our knowledge, this is the first report regarding the production of ATs by the infection of Alternaria sp. in yellow peach fruits via artificial inoculation under regulated conditions, and, based on the evidence herein, it is recommended that ATs be included in monitoring and control programs of yellow peach management and food safety administration.
    Type of Medium: Online Resource
    ISSN: 2072-6651
    URL: Article
    DOI: 10.3390/toxins13090656
    Language: English
    Publisher: MDPI AG
    Publication Date: 2021
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