Aflatoxin B1 M1 Research Articles

Optimization of Sampling for Monitoring Chemicals in the Food Supply Chain Using a Risk-Based Approach: The Case of Aflatoxins and Dioxins in the Dutch Dairy Chain.

Food safety monitoring faces the challenge of tackling multiple chemicals along the various stages of the food supply chain. Our study developed a methodology for optimizing sampling for monitoring multiple chemicals along the dairy supply chain. We used a mixed integer nonlinear programming approach to maximize the performance of the sampling in terms of reducing the risk of the potential disability adjusted life years (DALYs) in the population. Decision variables are the number of samples collected and analyzed at each stage of the food chain (feed mills, dairy farms, milk trucks, and dairy processing plants) for each chemical, given a predefined budget. The model was applied to the case of monitoring for aflatoxin B1/M1(AFB1/M1) and dioxins in a hypothetical Dutch dairy supply chain, and results were calculated for various contamination scenarios defined in terms of contamination fraction and concentrations. Considering various monitoring budgets for both chemicals, monitoring for AFB1/M1 showed to be more effective than for dioxins in most of the considered scenarios, because AFB1/M1 could result into more DALYs than dioxins when both chemicals are in same contamination fraction, and costs for analyzing one AFB1/M1 sample are lower than for one dioxins sample. The results suggest that relatively more resources be spent on monitoring AFB1/M1 when both chemicals’ contamination fractions are low; when both contamination fractions are higher, relatively more budget should be addressed to monitoring dioxins.

Aflatoxin B1 binding and toxic effects on Bacillus megaterium.

SUMMARY: A study was made of the binding of aflatoxin B1 and its toxic effects on Bacillus megaterium NRRL B-1368. After a 12 hr incubation period, 5 μg. aflatoxin B1m1. inhibited growth of the test organism 95 %. Viable organisms decreased from 3·8 ⨯ 107/ml. in the controls to 5·0 ⨯ 104/ml. in a growth medium containing 50 μg. aflatoxin B1/ml., after 4 hr. of incubation. Viability was not significantly decreased, however, when the organisms were incubated with the same concentration of toxin either under nitrogen, or at 5°, or in the presence of bacteriostatic concentrations of tetracycline. Binding experiments showed that 4·0 ⨯ 109 organisms/ml. took up approximately 7.0 μg. aflatoxin B1/ml. After five aqueous washes of the organisms, 20-25% of the toxin remained bound to them. The tightly bound toxin was removed by ultrasonic treatment of the organisms and chloroform extraction of the macerate. Removal of cell walls by lysozyme following toxin uptake released 23% of the initially bound toxin, and osmotic rupture of the protoplasts an additional 7%. Toxin was also taken up by intact and by ruptured protoplasts. Removal of nucleic acids from the membranes did not alter their capacity to bind aflatoxin B1.