scholarly journals Aflatoxin Testing in Peanuts: A Proficiency Assessment Scheme for Chinese Analytic Laboratories

2009 ◽  
Vol 92 (2) ◽  
pp. 481-486 ◽  
Author(s):  
Lei Bao ◽  
Zhenmin Bao ◽  
Yibing Zhang ◽  
Chengzhu Liang ◽  
Ning Lu ◽  
...  
Keyword(s):  
Aflatoxin B1 ◽  
High Performance ◽  
Robust Statistics ◽  
Enzyme Linked Immunosorbent Assay ◽  
Target Analytes ◽  
Sample Stability ◽  
Inspection And Quarantine ◽  
Z Scores ◽  
Iso 13528 ◽  
Proficiency Assessment

Abstract This national assessment program was established by the China National Accreditation Service for Conformity Assessment (CNAS) to evaluate the aflatoxin-testing proficiency of a cross-section of Chinese laboratories. The Shan Dong Inspection and Quarantine Bureau of China conducted the assessment according to ISO 13528:2005 (E) and the International Harmonized Protocol for Proficiency Testing. The 77 laboratories that participated in the study had either been previously accredited by CNAS or were candidates for CNAS accreditation. The analytic samples for this testing scheme were prepared from naturally contaminated peanuts and diluted to approximately 10 g/kg for aflatoxin B1 and 18 g/kg for total aflatoxins. The Ss/p test (with a required result of Ss 0.3p) was used to evaluate the homogeneity of the test samples; sample stability was confirmed with a t-test. The performance of each laboratory was designated by a z-score that was calculated using robust statistics. The robust mean of the participants' results in this study was nearly coincident with the median. A modified Horwitz equation was used to determine the standard deviation. The study compared analytic results obtained by 5 different methods: high-performance liquid chromatography (LC), enzyme-linked immunosorbent assay, thin-layer chromatography, fluorometry, and LC with tandem mass spectrometry. A satisfactory performance rating required z-scores between 2 and 2 for the target analytes. Of the 73 laboratories that reported results for aflatoxin B1, 66 (90.4) performed satisfactorily. Of 32 laboratories that reported total aflatoxins (B1 B2 G1 G2), 30 (93.8) performed satisfactorily. Laboratories whose performance ratings were questionable or unsatisfactory were re-evaluated in a second interlaboratory comparison.

Transfer of aflatoxins from naturally contaminated feed to milk of Nili-Ravi buffaloes fed a mycotoxin binder

2016 ◽  
Vol 56 (10) ◽  
pp. 1637 ◽  
Author(s):  
N. Aslam ◽  
I. Rodrigues ◽  
D. M. McGill ◽  
H. M. Warriach ◽  
A. Cowling ◽  
...  
Keyword(s):  
Aflatoxin B1 ◽  
High Performance ◽  
Mean Value ◽  
Aflatoxin M1 ◽  
Enzyme Linked Immunosorbent Assay ◽  
Treatment Groups ◽  
Low Concentrations ◽  
Daily Concentration ◽  
The Mean ◽  
Carry Over

The objectives of this study were to observe the extent of transfer of aflatoxin B1 in feed to the aflatoxin M1 metabolite in milk in Nili-Ravi buffaloes and to evaluate the efficacy of a commercial mycotoxin binder (Mycofix, Biomin Singapore) incorporated into feed to minimise this transfer. Multiparous animals (n = 28) were randomly distributed to four groups corresponding to two treatments each with two levels of aflatoxin B1. Individual animals were exposed to naturally contaminated feed providing a total of 1475 µg/day (Groups A and B) or 2950 µg/day (Groups C and D) of aflatoxin B1. Groups B and D were given 50 g of mycotoxin binder daily mixed with feed whereas Groups A and C were kept as controls. Feed samples were analysed by reverse phase high performance liquid chromatography for aflatoxin B1 and milk samples were evaluated by enzyme-linked immunosorbent assay for the liver metabolite aflatoxin M1. The mean value of total daily aflatoxin M1 excretion for animals fed 2950 µg/day of aflatoxin B1 (112.6 µg/day) was almost double (P < 0.001) than the excretion in buffaloes fed 1475 µg/day (62.2 µg/day). The mean daily concentration of aflatoxin M1 in milk of animals from both treatment groups supplemented with 50 g/day of mycotoxin binder was 76.5 µg/day, nearly 22 µg lower than those without binder at 98.3 µg/day (s.e.d. = 5.99: P < 0.01). The interaction of binder and treatment was not significant i.e. the 50 g/day of binder was able to sequester aflatoxin B1 with the same efficiency in groups fed with high and low concentrations of aflatoxin B1. Carry over was (3.44%) lower (P = 0.001) in animals supplemented with 50 g/day of mycotoxin binder than those fed no binder (4.60%). Thus buffaloes are highly efficient at transferring aflatoxins in feed to the aflatoxin M1 metabolite in milk, whereas mycotoxin binder is capable of alleviating without preventing this contamination risk.

scholarly journals The New Probiotic Lactobacillus Plantarum Strain Isolated from Traditional Dairy Showed The Synergistic Effect on Aflatoxin B1 Detoxification Along with Nanochitosan Particles

2021 ◽  
Author(s):  
Neda Zamani ◽  
Abbas Akhavan Sepahi ◽  
Mohammad Reza Fazeli ◽  
Farid Shariatmadari
Keyword(s):  
Antimicrobial Activity ◽  
Synergistic Effect ◽  
Aflatoxin B1 ◽  
High Performance ◽  
Synergistic Effects ◽  
Chitosan Nanoparticles ◽  
Food Products ◽  
Enzyme Linked Immunosorbent Assay ◽  
Different Strains

Abstract Background: Reduction of aflatoxin toxins in food products is of great importance. Therefore, in the present study, the effects of new Lactobacillus plantarum strain isolated from dairy products as well as chitosan nanoparticles were studied on reducing of aflatoxin B1 (AFB1) toxicity in vitro.Methods: After collection and preparation yogurt, cheese, milk and whey products, lactic acid bacteria (LABs) were isolated and identified using biochemical and molecular methods. To measure probiotic activity, pH, bile and salt tolerance tests were used. Then, the antimicrobial activity of LABs against gastrointestinal pathogens was studied. Next, the cheese-separated strain (C1) was selected as the superior strain and antibiotic susceptibility testing was performed. Then, the effect of C1 isolate and chitosan nanoparticles on reducing aflatoxin B1 (AFB1) in the medium was studied by measuring AFB1 using the enzyme-linked immunosorbent assay (ELISA) and high performance liquid chromatography (HPLC).Results: The results of biochemical evaluations indicated the separation of different strains of Lactobacillus plantarum. Antimicrobial activity test showed extensive antimicrobial activity of C1 isolate. The results showed that this strain has good probiotic activities. This strain was shown to be resistant to the antibiotics erythromycin, fusidic acid, gentamicin, kanamycin, nalidixic acid, neomycin, ofloxacin and vancomycin. C1 strain together with chitosan nanoparticles had the ability to reduce AFB1 in the medium and when both were used simultaneously, and synergistic effect in reducing AFB1 from the medium was seen.Conclusion: In general, it was concluded that the new C1 L. plantarum strains together with chitosan nanoparticles could have synergistic effects in reducing AFB1 toxin in food products.

scholarly journals Organisation of Multi-Mycotoxin Proficiency Tests: Evaluation of the Performances of the Laboratories Using the Triple A Rating Approach

Toxins ◽  
2021 ◽  
Vol 13 (9) ◽  
pp. 591
Author(s):  
Emmanuel K. Tangni ◽  
Bart Huybrechts ◽  
Julien Masquelier ◽  
Els Van Hoeck
Keyword(s):  
United States ◽  
Robust Statistics ◽  
The United States ◽  
International Standard Organization ◽  
Proficiency Tests ◽  
Z Scores ◽  
Iso 13528 ◽  
Standard Organization ◽  
The Stability

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.

scholarly journals A Case for Regular Aflatoxin Monitoring in Peanut Butter in Sub-Saharan Africa: Lessons from a 3-Year Survey in Zambia

2016 ◽  
Vol 79 (5) ◽  
pp. 795-800 ◽  
Author(s):  
SAMUEL M. C. NJOROGE ◽  
LIMBIKANI MATUMBA ◽  
KENNEDY KANENGA ◽  
MOSES SIAMBI ◽  
FARID WALIYAR ◽  
...  
Keyword(s):  
South Africa ◽  
Aflatoxin B1 ◽  
Peanut Butter ◽  
Aflatoxin Contamination ◽  
Comprehensive Analysis ◽  
Sub Saharan Africa ◽  
Enzyme Linked Immunosorbent Assay ◽  
Contamination Level ◽  
Batch Number ◽  
Sub Saharan

ABSTRACT A 3-year comprehensive analysis of aflatoxin contamination in peanut butter was conducted in Zambia, sub-Saharan Africa. The study analyzed 954 containers of 24 local and imported peanut butter brands collected from shops in Chipata, Mambwe, Petauke, Katete, and Nyimba districts and also in Lusaka from 2012 to 2014. For analysis, a sample included six containers of a single brand, from the same processing batch number and the same shop. Each container was quantitatively analyzed for aflatoxin B1 (AFB1) in six replicates by using competitive enzyme-linked immunosorbent assay; thus, aflatoxin contamination level of a given sample was derived from an average of 36 test values. Results showed that 73% of the brands tested in 2012 were contaminated with AFB1 levels &gt;20 μg/kg and ranged up to 130 μg/kg. In 2013, 80% of the brands were contaminated with AFB1 levels &gt;20 μg/kg and ranged up to 10,740 μg/kg. Compared with brand data from 2012 and 2013, fewer brands in 2014, i.e., 53%, had aflatoxin B1 levels &gt;20 μg/kg and ranged up to 1,000 μg/kg. Of the eight brands tested repeatedly across the 3-year period, none consistently averaged ≤20 μg/kg. Our survey clearly demonstrates the regular occurrence of high levels of AF B1 in peanut butter in Zambia. Considering that some of the brands tested originated from neighboring countries such as Malawi, Zimbabwe, and South Africa, the current findings provide a sub-Saharan regional perspective regarding the safety of peanut butter.

scholarly journals A comparison between enzyme immunoassay and HPLC for ochratoxin A detection in green, roasted and instant coffee

2007 ◽  
Vol 50 (2) ◽  
pp. 349-359 ◽  
Author(s):  
Simone Fujii ◽  
Elisabete Yurie Sataque Ono ◽  
Ricardo Marcelo Reche Ribeiro ◽  
Fernanda Garcia Algarte Assunção ◽  
Cássia Reika Takabayashi ◽  
...  
Keyword(s):  
Monoclonal Antibody ◽  
Ochratoxin A ◽  
High Performance ◽  
Screening Tool ◽  
Correlation Coefficients ◽  
Enzyme Linked Immunosorbent Assay ◽  
Elisa Assay ◽  
Quality And Safety ◽  
Green Coffee ◽  
Instant Coffee

An indirect competitive enzyme-linked immunosorbent assay (ic-ELISA) for ochratoxin A (OTA) detection in green, roasted and instant coffees was developed using anti-OTA monoclonal antibody. Immunological reagents prepared were OTA-BSA (4.76 mg/mL), anti-OTA.7 MAb (2x10³-fold dilution) and HRP-anti IgG (10³-fold dilution). The detection limit was 3.73 ng OTA/g and correlation coefficients (r) between this immunoassay and high performance liquid chromatography were 0.98 for green coffee, 0.98 for roasted and 0.86 for instant. OTA levels detected by ic-ELISA were higher than by HPLC, with ELISA/HPLC ratio of 0.66 - 1.46 (green coffee), 0.96 - 1.11 (roasted) and 0.93 - 1.82 (instant). ELISA recoveries for OTA added to coffee (5 - 70 ng/g) were 81.53 % for green coffee, 46.73 % for roasted and 64.35 % for instant, while recoveries by HPLC were 80.54 %, 45.91 % and 55.15 %, respectively. Matrices interferences were minimized by samples dilution before carrying out the ELISA assay. The results indicate that MAb-based ic-ELISA could be a simple, sensitive and specific screening tool for OTA detection, contributing to quality and safety of coffee products.

Διαχρονικές μεταβολές βιοενέργειας, μεταβολισμού και ανοσολογικής απόκρισης στην οξεία φάση της σοβαρής σήψης

2018 ◽  
Author(s):  
Άννα-Μαρία Σπανάκη-Μπαρμπουνάκη
Keyword(s):  
Body Mass Index ◽  
Flow Cytometry ◽  
Severe Sepsis ◽  
Heat Shock ◽  
Energy Expenditure ◽  
Systemic Inflammatory Response Syndrome ◽  
Enzyme Linked Immunosorbent Assay ◽  
Z Scores ◽  
Luminescent Assay ◽  
Shock Proteins

Εισαγωγή: Το κυτταρικό στρες από σοβαρή σήψη (severe sepsis, SS) ή σύνδρομο συστηματικής φλεγμονώδους απάντησης (Systemic inflammatory response syndrome, SIRS) εκδηλώνεται με οξείες φλεγμονώδεις, ορμονικές, ανοσολογικές και μεταβολικές διαταραχές. Η συσχέτισή τους με πιθανή δυσλειτουργία μιτοχονδρίων δεν έχει επαρκώς μελετηθεί. Σκοπός: Σκοπός της μελέτης ήταν η εκτίμηση των διαχρονικών μεταβολών φλεγμονώδους-ορμονικής αντίδρασης, ενδογενούς-ανοσίας, βιοενέργειας και μεταβολισμού σε ασθενείς, ενήλικες και παιδιά, με σοβαρή σήψη (SS) και η σύγκριση με αντίστοιχες ομάδες ασθενών με SIRS και υγιών (H), ενηλίκων και παιδιών.Υλικά/Μέθοδοι: Μελετήθηκαν 68 παιδιά (SS/18, SIRS/23, H/27) και 79 ενήλικες (SS/23, SIRS/23, H/33) διαχρονικά, την 1, 3η και 5η ημέρα νοσηλείας. Υπολογίστηκαν ο δείκτης μάζας σώματος (Body mass index (BMI) z-scores) και τα scores βαρύτητας νόσου (PeLOD, APACHE, TISS, SOFA). Μετρήθηκαν η καρδιακή συσταλτικότητα (EF, SF), η τροπονίνη (Tn), το γαλακτικό οξύ, η κατανάλωση ενέργειας (Energy expenditure, EE) με Gas Module E-COVX, το ATP στα λευκά αιμοσφαίρια με δοκιμασία λουσιφεράσης (luciferase luminescent assay), τα επίπεδα γλουταμίνης και NO2/NO3 με υγρή χρωματογραφία υψηλής πίεσης (HPLC), τα προϊόντα υπεροξείδωσης λιπιδίων (TBARS) με χρωματομετρική δοκιμασία, η ρεζιστίνη, η αντιπονεκτίνη ορού και οι εξωκυττάριες Heat Shock Proteins (HSP) με την ποσοτική ανοσοενζυμική μέθοδο ELISA (sandwich enzyme-linked immunosorbent assay), και οι ενδοκυττάριες HSP72, HSP90α με κυτταρομετρία ροής (flow cytometry). Αποτελέσματα: Διαχρονικά τόσο σε ενήλικες (ICU) όσο και σε παιδιά (PICU) οι τιμές ρεζιστίνης, αντιπονεκτίνης, εξωκυττάριας HPS72 και 90α παρουσιάζαν σταθερό πρότυπο διέγερσης σε όλη την οξεία φάση των 5 ημέρων. Στη χρονική αυτή περίοδο, οι παράμετροι μεταβολισμού VO2, VCO2, EE παρουσίασαν σταθερό υπομεταβολικό προφίλ, ίδιο σε ενήλικες και παιδιά. Η αυξημένη έκφραση των NO3, NO2, TBARS και αντιπονεκτίνης στη σήψη παρουσίασαν μια πιο ασταθή εικόνα όσον αφορά τη διαχρονική τους έκφραση ανά ηλικιακή ομάδα.Η βιοενέργεια των μιτοχονδρίων ήταν διαχρονικά μειωμένη σε ενήλικες κα παιδιά που δεν επιβίωσαν σε σχέση με εκείνους που επιβίωσαν, και συνοδεύονταν από σημαντικά μειωμένο μεταβολισμό και υπομεταβολικά πρότυπα την 3η και 5η ημέρα (p<0.05). Οι ασθενείς που επιβίωσαν παρουσίαζαν σημαντική διαφοροποίηση των αρχικών τιμών BVR, γαλακτικού, ΕΕ, VO2, VCO2 και μεταβολικού προφιλ σε σύγκριση με ασθενείς που πέθαναν, οι οποίοι έδειξαν αδυναμία ανάκαμψης του υπομεταβολισμού ή της αντιοξειδωτικής κατάστασης την 5η ημέρα. Συμπέρασμα: Η SS χαρακτηρίζεται διαχρονικά, από ισχυρότερη ενδοκυττάρια καταστολή μεταβολισμού, μείωση κατανάλωσης ενέργειας, μείωση των ATP, HPS72, HSP90α, αλβουμίνης, γλουταμίνης και εξωκυττάρια αύξηση φλεγμονωδών ορμονών, ρεζιστίνης και αντιπονεκτίνης και πρωτεϊνών έμφυτης ανοσίας (HSP72). Μια πρώιμη κατάσταση υπομεταβολισμού, με καταστολή βιοενέργειας και ενδογενούς ανοσίας, η οποία και παραμένει διαχρονικά μαζί με συνεχιζόμενη κατάσταση φλεγμονής, με διαχρονικά αυξημένες μεταβολικές ορμόνες και πρωτείνες eHSP72/HSP90α, φαίνεται να ξεχωρίζει τη σήψη από το SIRS, και συνδέεται με αυξημένο κίνδυνο θανάτου.Λέξεις κλειδιά: σήψη, SIRS, βιοενέργεια, HSP, μιτοχόνδρια, μεταβολισμός, θερμιδομετρία, αμινοξέα, οξείδιο του αζώτου, ATP, ρεζιστίνη, αντιπονεκτίνη, τραύμα

Sign in / Sign up

Export Citation Format

Share Document