الفهرس 
Review of LiteratureOnly 14 pages are availabe for public view
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Abstract
Wheat was one of the most important cereals produced and
consumed in Mediterranean countries. Wheat (Triticum aestivum L. em
Thell.), family Poaceae (Gramineae) was the first important and strategic
cereal crop for the majority of world’s populations. It was the most
important staple food of about two billion people (36% of the world
population). Worldwide, wheat provided nearly 55% of the carbohydrates
and 20% of the food calories consumed globally (Breiman and Graur,
1995). The annual total wheat grain yield in the world reached 628 million
tons, one third of it being harvested in Europe (Нуриев and Рудобашта,
2001).
The highest wheat per capita consumption levels in the world (180 kg
/person/year) was in Egypt. Egypt consumed about 14 million tons of wheat
annually and imported about half of this amount in 2010/2011.While the
total production of wheat in Egypt was 8.5 million tons harvested from 3.3
million Feddan (Capmas, 2011).
Globally, wheat was the leading source of vegetarian protein in
human food, having higher protein content than either maize or rice and the
other major cereals. In terms of total production tonnages used for food, it
was currently second to rice as the main human food crop, and ahead of
maize, after allowing for maize’s more extensive use in animal feeds.
Grains were regarded as highly effective means for transporting
plant pathogens over long distances. Numerous examples exist in
agriculture literature for the international spread of plant diseases as a result
of the importation of grains that were infected or contaminated with
pathogens (Agarwal and Sinclair, 1996). Grain borne diseases had been
found to affect the growth and productivity of crop plants (Dawson &
Introduction
2
Bateman, 2001 and Weber et al., 2001). A seedborne pathogen presented
externally or internally or associated with the grain as contaminant, may
cause grain abortion, grain rot, grain necrosis, reduction or elimination of
germination capacity as well as seedling damage resulting in development
of disease at later stages of plant growth by systemic or local infection
(Fakhrunnisa et al., 2006 and Khanzada et al., 2002).
The problem of grains contamination by pathogenic or saprophytic
fungi was a very serious problem, especially of the safety of human beings,
because they were used either in direct consumption or in food production.
Mycotoxins were naturally occurring chemical compounds produced by
theses fungi (e.g Aspergillus sp., Fusarium sp., Penicillium sp.). These fungi
on the surface of grains could appear during the transport and storage
processing. Although not all, moulds produce toxic substances called
mycotoxins (aflatoxin B1, B2, G1, G2, M1, ochratoxin A, zearalenone and
fumonisin ) cause diseases or illness when eaten by humans and animals
(Ciccarese et al., 2007).
Stored grains could have losses in both quantity and quality. Losses
occur when the grain was attacked by microorganisms and other organisms
including Fungi, insects, mites, rodents and birds (Neethirajan et al., 2007).
Cereal grains could be contaminated by a great variety of
microscopic fungus during its development. These pathogens may affect the
plant resulting in a reduction of the grain quality; some species could even
release natural toxins that cause human and animal intoxication
(Scudamore, 2005). Mould fungi degrade not only the quantative but also
qualitative grain and grain product indices (Young et al., 2006). In addition,
the majority of mould fungi were able to synthesize in certain conditions
mycotoxins harmful to humans and livestock (Lugauskas et al., 2002).
Introduction
3
Their spread and mycotoxin production depend on many factors including
agricultural technology of growing, temperature and moisture, conditions
during crop harvesting and storage (Marin et al., 1998; Homdork et al.,
2000; Baliukonienė & Bakutis, 2002 and Bartels & Rodemann, 2003).
Disinfection of grain was a widely applied measure to conserve its
quality. As a means of grain disinfection (against mould fungi and their
toxins) various chemicals were investigated (sodium hypochlorite, various
antioxidants and others) (Ramakrishna et al., 1991; Andrews et al., 1997
and Nesci et al., 2003).Physical disinfection means were among the most
promising ones being the least harmful to the environment, and they
included grain cleaning, thermal processing, exposure to high frequency
electromagnetic oscillation, to electron flux, luminescence and others
(Ramakrishna et al., 1991; Andrews et al., 1997; Baba et al., 2004 and
Cutrubinis et al., 2005).
Ozone could be used for the purpose of microbial reduction and had
the ability to oxidise organic material including the cell wall of an organism.
Treatments of with aqueous ozone had been shown to destroy aflatoxins
(Dwarakanath et al., 1968).