Aflatoxin M1 in pasteurized, UHT milk and milk powder commercialized in Londrina, Brazil and estimation of exposure / Aflatoxina M1 em leite pasteurizado e UHT e leite em po comercializados em Londrina, Brasil e exposicao estimada.

Aflatoxin M1 (AFM1) is found in milk and other excretion products after aflatoxin B1 intake. AFM1 is carcinogenic to humans, and known levels of dairy product contamination is important to understand the risks to which the population is exposed. The occurrence of AFM1 was evaluated in 42 milk samples commercialized in Londrina, Parana State, Brazil and this rate of occurrence was used to estimate this exposure. AFM1 determina tion was ca rried out by ELISA, and was detected in 100 % samples at levels ranging from 0.01 to 0.81 µ g/kg (mean 0.13 µ g/kg). None of the samples p resente d AFM1 above the maximum permitted level by Brazilian Legislation (0.5 µ g/kg for fluid milk and 5 µ g/kg for milk powder). The estimated daily intake (EDI) of AFM1 was evaluated, and the average intake was 0.468 ng/kg body weight (b.w.) for adolescents, 0.384 ng/kg b.w. for adults and 0.559 ng/kg b.w. for the elderly. Values of EDI of AFM1 found in Londrina pose a toxicological risk to the population investigated. To the best of our knowledge, this is the first report on estimat ed AFM1 dietary exposure from Parana, Brazil.

Aflatoxina M1 (AFM1) e encontrada no leite e em outros produtos de excrecao apos o consumo de aflatoxina B1. AFM1 e carcinogenica para humanos, e avaliar os niveis de contaminacao em produtos lacteos e importante para conhecer os riscos aos quais a populacao esta exposta. A ocorrencia de AFM1 foi avaliada em 42 amostras de leite comercializadas em Londrina, Estado do Parana, Brasil, e sua ocorrencia foi utilizada para estimar sua exposicao. A determinacao de AFM1 foi avaliada por ELISA, e foi detectada em 100% das amostras, em niveis variando de 0,01 a 0,81 µ g/kg (media 0,13 µ g kg). Nenhuma das amostras apresentou niveis de AFM1 acima do maximo permitido pela Legislacao brasileira (0,5 µ g/kg para leite fluido e 5 µ g/kg para leite em po). A ingestao diaria estimada (IDE) de AFM1 foi avaliada, e a ingestao media foi de 0,468 ng/kg de peso corporal (p.c.)/dia para adolescentes, 0,384 ng/kg p.c./dia para adultos e 0,559 ng/kg p.c./dia para idosos. Valores de IDE de AFM1 encontrados em Londrina supoem um risco toxicologico para a populacao investigada. Do melhor do nosso conhecimento, este e o primeiro trabalho sobre a exposicao estimada de AFM1 do Parana, Brasil.

Aflatoxin M1 preparation and identification of artificial antigens / 中国免疫学杂志

Objective:AFM1-BSA and AFM1-OVA were synthesized and then identified in this experiment.Methods: Using oximation method ,AFM1 was transformed to oxime compounds while the reaction process was monitored via TLC method aiming to identify the compounds.Coupled with carrier protein BSA and OVA respectively , we obtained AFM1-BSA and AFM1-OVA, then identified synthetic antigen via UV spectrophotometry and SDS-PAGE.Antigens were injected into experimental animals , finally obtaining the murine multi-antiserum.Eventually , the multi-antiserums were detected via indirect inhibition ELISA method to judge whether the antigens were effectively or not.Results:After oximation reaction ,the migration distance of oxime compounds in the thin layer plate was shorter.The maximum absorption peak of AFM1-BSA occurred in 274 nm,and was inconsistent with both UV absorption peaks of BSA and AFM 1.The electrophoretic velocity of AFM 1-BSA was less than that of BSA.All the titers of three immunized mice were 1×10-4 approximately;the multi-antiserum from No.3 sample had the best sensitivity ,its IC50 was 359.9 ng/ml.Conclusion:In this study,we obtained AFM1 artificial antigen and murine multi-antiserum of high sensitivity.