Alkhartoum university
Faculty of animal
production
5th level
18th patch
Seminar Title
Mycotoxins and the food chain
REHIS Trainers' Seminar, October
2009
Introduction
food poisoning
1.Bacteria or their toxins
2.Viruses
3.Chemicals
4.Poisonous plants
(deadly nightshade) and fungi
(poisonous mushrooms)
5.Natural toxicants - plants, fish,
mycotoxins
5.Allergy - not the result of food being
contaminated
REHIS Trainers' Seminar, October
2009
Mycotoxins
Secondary metabolites (chemicals) of a
fungus that produce toxic results in
another organism
toxins produced by micro-fungi
Aspergillus spp.Macro-fungi
mushrooms.
Mycotoxins have 4 basic toxicity - acute,
chronic, mutagenic, teratogenic.
REHIS Trainers' Seminar, October
2009
Mycotoxigenic filamentous fungi
Rhizopus spp.
Byssochlamys spp.
Claviceps spp.
Eupenicillium spp.
Eurotium spp.
Neosartorya spp.
Talaromyces spp.
Alternaria spp.
Aspergillus spp.
Penicillium spp.
Fusarium spp.
Cladosporium spp.
Geotrichum candidum
Paecilomyces variotii
Phomopsis spp.
Stachybotrys spp.
Trichoderma viride
Wallemia sebi
REHIS Trainers' Seminar, October
2009
*Range from single cells to fruiting
bodies that form molds, mushrooms,
smuts, and yeasts.
*Absorb nutrients from living or
deceased organisms, contain no
chlorophyll.
*If multicellular, they have tubular
filaments called hyphae that branch out.
*Reproduce using spores
REHIS Trainers' Seminar, October
2009
*Relative humidity over 70%.
*Temperatures over 30 degrees
Centidrade.
*Stress to the affected plant, such as
drought, flood, or insect infestation.
*High moisture content of crop (20%
or higher).
*Must occur in conjunction, or fungal
growth cycle will cease.
REHIS Trainers' Seminar, October
2009
Types of mycotoxins
There are over 300 mycotoxins but the commonly
occurring ones in food and feed.
*Aflatoxins (B1,
B2, G1, G2, M1)
*Ochratoxin A
*Zearalenone
*Fumonisins
*Trichothecenes
*Patulin
*Moniliform
*Sterigmatocystin
*Citrinin
*Cyclopiazonic acid
*Kojic acid
*Maltoryzine
*ß-nitropropionic
acid
*Aspergillic acid
*Penicillic acid
*Roquefortine C
REHIS Trainers' Seminar, October
2009
Fungal Infection
*Can occur at any stage in crop production.
*While in the field.
*During harvesting.
*While in silage and storage.
*Spores can lay dormant for months to years,
waiting for positive conditions for
germination.
REHIS Trainers' Seminar, October
2009
Mycotoxin Chain of Events
REHIS Trainers' Seminar, October
2009
Principal toxigenic moulds and food crops
Aspergillus ochraceus – ochratoxins, penicillic
acid
cereals, nuts, pulses, oilseeds, corn.
A. flavus or A. parasiticus – aflatoxins
cereals, nuts, root crops, oilseeds, pulses.
Penicillium spp. – ochratoxin, patulin, citrinin
cereals, root crops, nuts, beans.
Fusarium spp. – T-2 toxins, zearalenone
cereals and root crops.
REHIS Trainers' Seminar, October
2009
Symptoms of Mycotoxicosis
1. Drugs and antibiotics are not effective in
treatment.
2. symptoms can be traced to foodstuffs or feed.
3. Testing of said foodstuffs or feed reveals fungal
contamination.
4. symptoms are not transmissable person to
person.
5. The degree of toxicity is subject to persons age
(more often in very young and very old), sex ( more
often in females than males)and nutritional status.
6. Outbreaks of symptoms appear seasonally
REHIS Trainers' Seminar, October
2009
Mycotoxin Effects on Animals
*Feed refusal.
*Impaired animal health, resulting in
reduced production of eggs, milk, weight
gain, etc.
*Metabolites are passed through the milk in
cheese, dry milk, and yogurt.
*Disease.
*Death in animals
REHIS Trainers' Seminar, October
2009
REHIS Trainers' Seminar, October
2009
Organ System Affected
Toxin(s)
Vascular
Aflatoxin
Digestive
Aflatoxin, T-2toxin, Vomitotoxin
Respiratory
Trichothecenes
Nervous
Trichothecenes
Cutaneous
Tricothecenes
Urinary
Ochratoxin A, Citrinin
Reproductive
Zearalenone, T-2 toxin
Immune
Many
REHIS Trainers' Seminar, October
2009
Future Fight Against Mycotoxins
*Scientists hope to genetically engineer plants
resistant to fungal infection.
*Use feed additives that sequester the toxins
and prevent absorption from the
gastrointestinal tract.
REHIS Trainers' Seminar, October
2009
Potential uses of mycotoxins
Medical application - Trichothecenes
are known to possess antileukaemic
activity; zearalenone derivatives have
been considered as potential treatment
for menopausal syndrome in women;
Agriculture application - derivatives of
zearalenone as growth promoter in
sheep and cattle; other mycotoxins
have been considered for use as
herbicides and insecticides.
REHIS Trainers' Seminar, October
2009
Referance: Websites
UK Food Standards Agency,2002. Survey of nuts, nut products and dried tree
fruits for mycotoxins. Food Survey Information Sheet 21/02
http://www.food.gov.uk/science/surveillance/fsis2002/21nuts
UK Food Standards Agency, 2004. Survey of baby foods for mycotoxins,
Food Survey Information Sheet 68/04.
http://www.food.gov.uk/science/surveillance/fsis2004branch/fsis6804
UK Food Standards Agency, 2005. Survey of wheat for ochratoxin A, Food
Survey Information Sheet 77/05.
http://www.food.gov.uk/science/surveillance/fsis2005/fsis7705
UK Food Standards Agency, 2005. Survey of spices for aflatoxins and
ochratoxin A, Food Survey Information Sheet 73/05.
http://www.food.gov.uk/science/surveillance/fsis2005/fsis7305
UK Food Standards Agency, 2005. Survey of maize-based retail products for
mycotoxins, Food Survey Information Sheet 72/05
http://www.food.gov.uk/science/surveillance/fsis2005/fsis7204
UK Food Standards Agency (FSA) 2009a. Review of Programmes C03 &
C04 (Mycotoxins and Nitrate). Final Report. 48pp.
UK Food Standards Agency (FSA) 2009. Food Contaminants. Update Bulletin,
March. www.food.gov.uk
REHIS Trainers' Seminar, October
2009
REHIS Trainers' Seminar, October
2009