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Journal of Ecosystem & Ecography | ISSN: 2157-7625 | Volume: 8
June 28-29, 2018 | Alexandria, Egypt
International Pre Conference Workshop on
Microbial Ecology & Eco Systems
with allergic tendencies. What makes the problem even worse is that the fungus was shown to have developed signs of drug resistance
(Tamgadge et al., 2012).
Additionally, it was reported that most infections of otomycosis which is a chronic condition endemic in tropical and subtropical
regions and is rarely reported in infants and children are due to A. niger or, less commonly, A. fumigatus. Most cases are unilateral, and
patients complain of ear pain, itching of the auditory canal, and a sense of fullness. Otorrhea (decreased hearing) and tinnitus (ringing
or buzzing in the ears) are less common. Examination of the auditory canal typically shows conidial "forests" or mycelial mats (Paulose
et al., 1989; Rutt, and Sataloff, 2008; Jia et al., 2012).
Botrytis cinerea is another plant pathogen known to infect large number of fruits and vegetables causing the grey mold disease. The
fungus infecting grapes may also infect man causing "winegrower's lung" among farmers (Popp et al., 1987). The disease is a rare form
of hypersensitivity pneumonitis (a respiratory allergic reaction in predisposed individuals). Symptoms include fever, chills, malaise,
cough, chest tightness, dyspnea, rash, swelling and headache. Symptoms resolve within 12 hours to several days upon cessation of
exposure (Sharma, 2006).
Despite the question about the possible direct effect of plant pathogens on humans, Plant pathogens may negatively affect human health
indirectly by reducing crop quantity and quality including nutritional value. Several plant pathogens (Aspergillus spp., Penicillium
spp., Fusarium spp., Claviceps spp.) can affect humans by reducing the available food or by contaminating human food with toxic
compounds (Baranyi, 2013; Cary et al., 2017
One of the most common ways through which plant diseases can indirectly affect human health is through excreting toxic metabolites
’mycotoxins’ by fungi infecting plant products. Although the fungi producing these mycotoxins are plant pathogens and do not infect
humans, they can do that indirectly through the mycotoxins they excrete causing harm to human and animal health resulting in
diseases and death. Examples of fungal species producing mycotoxins include A. flavus, A. parasiticus, Fusarium spp. and Penicillium
spp. Several groups of mycotoxins have been recognized, of which Aflatoxins (types =B1, B2, G 1 and G 2) are one of the most dangerous
ones. Although Aflatoxins have long been known to be produced mainly by two main Aspergilli (A. flavus and A. parasiticus), but
recently 20 different species of Aspergillus (e.g. Aspergillus ochraceoroseus) and other genera have been reported to produce Aflatoxins
(Baranyi, 2013).
Feeding on plant parts contaminated with aflatoxins causes a syndrome known as aflatoxicosis which is characterised by vomiting,
abdominal pain, pulmonary edema, convulsions, coma, and death with cerebral edema and fatty involvment of the liver, kidneys,
and heart. Aflatoxins are highly carcinogenic metabolites of which Aflatoxin B1 is frequently referred to as the most potent naturally
occurring carcinogen. It is considered to be 1000 times more potent as a carcinogen than benzopyrene. The toxin is lethal at high doses
and is carcinogenic to humans at low doses and can result in reduced liver function, vomiting and abdominal pain. Annual deaths
in some parts of Africa due to the effect of aflatoxin have been reported to reach 250,000 annually (Wild et al., 1992). Mycotoxins
can be consumed indirectly by humans through the consumption of meat from animals fed on feed contaminated with mycotoxin
excreting Aspergilli. Evidence of acute aflatoxicosis in humans has been reported frommany parts of the world, namely theThirdWorld
Countries, like Taiwan, Ouganda, India, and many others.
The fungus Claviceps purpurea, beside some other species of the same genus, is another plant pathogen that infects cereals including
wheat causing a disease called ergot (Kien and Cvak. 1999). The fungus is characterised by the production of hard fungal mycelial
structures termed sclerotia that replace grains in the spikes of their hosts (Miedaner and Geiger, 2015). Sclerotia contains over 40
different toxic alkaloids. of which some may have psychedelic (e.g. Lysergic acid and Lysergic acid amide), vasoconstriction (e.g.
Ergotamine, Ergochristine and Ergocryptine), smooth muscle contracting (e.g. ergometrine) and hallucinating (e.g. lysergic acid
diethylamide) effects. The hallusinating compound “lysergic acid diethylamide” (known as LSD) is produced during the baking of
bread made with ergot-contaminated wheat. Consumption of bread produced from contaminated flour can thus result in ergotism
disease in humans. Ergotism has been reported to result in Dry gangrene of hand, foot and leg from poor circulation (Balique, 1968),
loss of peripheral sensation, hallucinations or even death (Křen and Cvak, 1999; White et al., 2003).
Although LSD is relatively non-toxic and non-addictive, various governments around the world outlawed it after a number of fatal
accidents were reported. Such accidents involved, for example, people under the influence of LSD jumping to their deaths off high