23 October 2017

Aflatoxins - The risk in mold

Natural toxin

Aflatoxins are a carcinogenic group of mycotoxins produced by certain molds from genera Aspergillus.

Certain strains of Aspergillus flavus and A. parasiticus are the main producers of several types of aflatoxins, being aflatoxin B1 the most hepatotoxic and hepatocarcinogenic. Its production is dependant on several factors such as temperature, pH or
available nutrients.

The natural habitat of these kind of molds is soil, but it can propagate to any organic substrate under favorable conditions: high humidity and temperature. That is what can happen to improperly stored raw food commodities without fungicide treatment. Aflatoxins are responsible for many economic loss in crops such as cassava, chili peppers, corn, cotton seed, millet, peanuts, and rice, among others. Measurements to control them are proper storage and drying of stored crops, as well as sampling and testing of the field for Aspergillus.

Large doses of the toxin produces acute aflatoxicosis: necrosis, cirrhosis, and carcinoma of the liver showed by acute liver damage, edema, alteration in digestion, and absorption and/or metabolism of nutrients. Adult humans have quite a high tolerance for acute aflatoxicosis, while children are usually the ones affected in reported acute poisonings. Subclinical exposure results in the chronic form of the disease and leads to a high risk of developing liver cancer, due to the ability of the radical epoxide intermediate to intercalate into DNA.

Structure of aflatoxin B1 (polycyclic aromatic compounds). Click photo for 3D model

CAS number: 1162-65-8

SMILES code: COC1=C2C3=C(C(=O)CC3)C(=O)OC2=C4C5C=COC5OC4=C1