Gamma radiation against toxigenic fungi in food, medicinal and aromatic herbs

Practices of harvesting, handling and production may cause additional contamination and microbial growth. In fact, bacteria and fungi occur naturally as a microflora of fruits, vegetables and herbs. Microbial purity is an important aspect of wholesome products, considering that medicinal plants are often collected from wild sources. These products are sold in open-air markets, and most toxigenic moulds grow very well in this environment when exposed for long periods in open markets, without protective packaging, proper temperature maintenance, and moisture control. The presence of toxigenic moulds represents a potential risk of mycotoxin contamination. Mycotoxins are secondary metabolites produced by different fungi genera as Aspergillus, Fusarium and Penicillium. Among the mycotoxins, aflatoxin B1 (AFB1) is the one most commonly found in food and is considered to be the most toxic compound, with the liver representing the main target organ and this mycotoxin is produced by Aspergillus flavus and Aspergillus parasiticus. In addition to its hepatotoxic action, AFB1 is also highly mutagenic, carcinogenic, and probably teratogenic to animals and the International Agency for Research on Cancer (IARC) has classified AFB1 as a group 1 human carcinogen. The regulatory recommendations determine the detection of aflatoxins in food or medicinal plants, which presence, even in small amounts, can be hazardous to health. The treatment using ionizing radiation to the decontamination of fresh fruits and vegetables to eliminate pests from imported agricultural commodities was reported in many studies. Irradiation has been used to preserve foods and this method inactivates microorganisms that decompose foods, particularly bacteria, moulds and yeasts. This treatment also destroys pathogenic organisms, including worms and insects, which degrade the quality of stored foods. Ionizing radiation has been widely recognized as a method of decontamination of foodstuffs and medicinal plants.