This document discusses mycotoxins, which are toxic compounds produced by fungi. It provides background on mycotoxins, including their origin in fungi, mechanisms of toxicity, history, major types, and factors affecting their production. The document also summarizes the health impacts of mycotoxin exposure and discusses interventions and prevention strategies.

1. FOOD MICROBIOLOGY-2
Prepared By:
Md. Nahian Rahman
Institute of Nutrition and Food Science
15th Batch, University of Dhaka.

2. Key Points
 Introduction
 Origin of Mycotoxin
 Mechanism Of Toxicity
 History
 Types of Mycotoxin
 Factors affecting the production of mycotoxin
 Effects of Mycotoxins in Foods
 Health impact
 Intervention
 Prevention
 Conclusion

3. Introduction
A mycotoxin {from Greek (mykes, mukos) means "fungus"
and (toxikon) means"poison“} , a toxic secondary metabolite
which is produced by organisms of the fungi kingdom,
commonly known as molds. The term 'mycotoxin' is usually
reserved for the toxic chemical products produced by
fungi. One mold species may produce many different
mycotoxins, and the same mycotoxin may be produced by
several species.
300-400 compounds are recognized as mycotoxins, many
received attention as human threats .
Mycotoxins are associated with human disease and cause
acute and chronic effect

4. Origin of Mycotoxin
 Most fungi are aerobic (use oxygen) and are found almost
everywhere in extremely small quantities due to the minute size
of their spores. They consume organic matter wherever humidity
and temperature are sufficient. Where conditions are right,
fungi proliferate into colonies and mycotoxin levels become
high. The reason for the production of mycotoxins is not yet
known; they are not necessary for the growth or the development
of the fungi. Because mycotoxins weaken the receiving host, the
fungus may use them as a strategy to better the environment for
further fungal proliferation.
 The production of toxins depends on the surrounding intrinsic
and extrinsic environments and the toxins vary greatly in their
severity, depending on the organism infected and its
susceptibility, metabolism, and defense mechanisms.

5. Mechanism Of Toxicity
 Bind to DNA and RNA
 Alters protein synthesis and functions (e.g. enzymes)
 Oxidative stress (e.g. lipid peroxidation)
 Depletes antioxidants
 Alters cell membrane function and transport
 Potent mitochondrial toxins (numerous mechanisms)
 Alters apoptosis

6. History
 The term mycotoxin was used for the first time in 1961
in the afterward of a veterinary crisis in England,
during which thousands of animals died. The disease
was linked to a peanut meal , incorporated in the diet,
contaminated with a toxin produced by the
filamentous fungus Aspergillus flavus.
 Mycotoxicosis in horses first reported in 1931 (Ukraine)
Massive numbers of horses died with gastrointestinal
bleeding.
 “Chemical Defence system” of the fungi or mold.

7. Types of Mycotoxin
 Aflatoxins : B1, B2, G1, and G2.
 Ochratoxin: Ochratoxin A (OTA), Ochratoxin B
(OTB), Ochratoxin C (OTC)
 Citrinin:
 Ergot Alkaloids
 Patulin
 Fusarium: Fumonisins , Trichothecenes ,
zearalenone.
 T-2 Toxin, Deoxyniba-lenol (DON) or Vomitoxin-
Natural Toxic

8. Factors Affecting the production of
mycotoxin
1.Physical factors
i) Temperature and ERH during storage: Temperature (40 - 90o F ; 4 - 32o C),
Relative Humidity (> 70%)
ii) Aeration -Oxygen (1-2%)
iii) Light
iv) Mechanical damage (e.g. to shells of nut)
2. Chemical factors
i) Nutritional factors,Including inorganic ions
ii) Use of fungistats
3. Biological Factors
i) Strain of organism
ii) Competitive growth of fungi
iii) Microbial detoxication

12. Long term Health Impact
 Food poisoning and vomiting (vomitoxin)
 Aflatoxicosis (aflatoxin)
 Aplastic anemia (bone marrow failure) and bleeding
(trichothecenes)
 Acute pulmonary hemorrhage
 Cancer (aflatoxins)
 Birth defects (fumonisins)
 Tricothecenes inhibit protein synthesis
 Ochratoxins and citrinin cause nephropathy and
immunosuppression
 Even Death can occur

13. Short term Health Impact
 Vomiting
 Abdominal pain
 Hepatitis
 Impaired growth
 Itchy eyes
 Nausea
 Fatigue
 Increased respiratory tract infection
 Difficulty in concentrating
Lethal dose for adults: 10-20 mg

14. INTERVENTIONS
 To reduce airborne exposures to molds:
 Keep indoor areas dry
 Fix all leaks and clean up flooding within 24 hours
 Do not smoke indoors
 To reduce foodborne exposure to aflatoxin:
 Protect agricultural crops from moisture during both
growth and post-harvest storage
 Do not eat grains with visible mold
 Computer models to predict mycotoxin levels

15. INTERVENTIONS AFTER FLOODS
 Tetanus booster
 Food & water safety
 Sanitation & hygiene
 Power outages
 Carbon monoxide
 Animal & insects
 Cleanup
 Mold and mycotoxins
 Electrical hazards
 Reentering flooded buildings

16. PREVENTION AND EDUCATION
Protect child and pregnant woman from ingesting or
inhaling mycotoxins
 Foods (especially grains)
 Water-damaged, moldy homes
 Folic acid supplements for women
Protect agricultural crops
 Growth
 Post-harvest
Education
 Community leaders
 Consumer knowledge
 Human Health Effects of Mycotoxin Exposure

17. Conclusion
Mycotoxins toxicology has bought out many adverse
effects in human health and many outbreaks have
occurred all over the world costing many life's. If
carefully observed this toxication can be prevented. Still
many new methods of preventing the toxin can be found
out through research in future.