Excessive Free Radicals Due to Ingestion of Aflatoxin (S) Contaminated Food Needs More Dietary Antioxidants

Abstract

Aflatoxin(s) have been extensively studied with respect to their occurrence and prevalence on wide range of agricultural commodities, foods and feedstuffs. Also, toxicity and carcinogenicity on different animal species and human were studied. Survey studies collected from different developed and developing countries exhibited that foods of both plant and animal origin had the same opportunity to be aflatoxin(s)-contaminated food. Most, if not all published studies agreed that aflatoxins B1, B2, G1 and G2 were  the naturally  occurring forms of aflatoxins, but aflatoxin B1 was proved to be the most  common and potent form of aflatoxins which occurred naturally. Ingestion of aflatoxin(s)-contaminated food had certain metabolic pathways of ingestion and biotransformation. The highly oxygenated molecule of aflatoxin B1 (AFB1) take  place the biotransformation processes of reduction, hydroxylation, hydrogenation aiming to yield less toxic and more water soluble metabolites as a body defense mechanisms of detoxification and elimination. Only, the biotransformation process of epoxidation to form AFB1- 2,3 epoxide yielded a more potent and highly reactive metabolite.  Such high reactive metabolite of AFB1- 2,3 epoxide take place, certain bio-reactions of conjugation and adduct to protein fragments and nucleic acids. However, the metabolic pathways of aflatoxin(s) either yielded more or less toxic metabolites accompanied with excessive released free radicals. The difference is only related to the free radicals species, means that in case of transforming to less toxic metabolites, the reactive oxygen species (ROS) are dominating, while biosynthesis of AFB1- 2,3 epoxide accompanied with reactive nitrogen species (RNS). Recently, a variety of synthetic medicine employed in the treatment of free radicals. So, it's worthy to recommend suitable intake of fresh vegetables and fruits which are very rich in antioxidants and phytoconstituents.