Assessment of Aflatoxin M1 Levels by Enzyme-linked Immunosorbent Assay in Yoghurt Consumed in Tehran, Iran

Abstract

Aflatoxins are the best known and most intensively researched mycotoxins produced by different species of Aspergillus namely A. flavus, A. parasiticus, A. bombycis, A. ochraceoroseus, A. nomius and A. pseudotamari, which contaminate agricultural commodities and feeds, particularly at a critical temperature and humidity conditions. The main types of aflatoxins are B1, B2, G1, G2, M1 and M2 . Aflatoxins are highly toxic, mutagenic, immunosuppressive, teratogenic and carcinogenic compounds that have been implicated to be the causative agents in human hepatic and extrahepatic carcinogenesis. Aflatoxin M1 (AFM1) has been found in the milk of animals when lactating animals are fed with aflatoxin B1 (AFB1) contaminated feeds. The International Agency for Research on Cancer of World Health Organization included aflatoxin B1 as primary and aflatoxin M1 as secondary groups of carcinogenic compounds. Aflatoxin M1 is the monohydroxylated metabolite of aflatoxin B1 forming in liver by means of microsomial cytochrome P450associated enzymes. There was a linear relationship between the amount of aflatoxin M1 in milk and aflatoxin B1 in the feed, which is consumed by these animals. Monitoring studies reported that approximately 0.3-6.2 % of aflatoxin B1 ingested by livestock is transformed to aflatoxin M1 in milk. However, this Assessment of Aflatoxin M1 Levels by Enzyme-linked Immunosorbent Assay in Yoghurt Consumed in Tehran, Iran