Sources of major toxin groups and their toxicity

Mycotoxins are secondary metabolites produced by filamentous microfungi. Fungi are major plant and insect pathogens. Disease caused by fungi growth on animal hosts called mycoses. Whereas disease caused by exposures to toxic fungal metabolites known as mycotoxicoses which is what we concern mainly in package 2 currently.

In contrast to mycoses, mycotoxicoses are examples of “poisoning by natural means”. The symptoms of a mycotoxicosis depend on the type of mycotoxin; amount and duration of exposure; age, health, and individual gender. The majority of mycotoxicoses result from eating contaminated foods. Skin contact with mould-infested substrates and inhalation of spore-borne toxins are also important sources of exposure.

While all mycotoxins are of fungal origin, not all toxic compounds produced by fungi are called mycotoxins. Acute mycotoxicoses generally has a rapid onset and an obvious toxic response, while chronic mycotoxicoses is characterized by low-dose exposure over a long time period, resulting in cancers and other generally irreversible effects.

Generally, mycotoxin exposure is more likely to occur by poor methods of food handling and storage. Controlling mycotoxins can be prevented by applying good agricultural practice and sufficient drying of crops after harvest.

Below are summary of toxin groups, sources of origination, toxicity, and legal limit:

Aflatoxin
Aspergillus flavus and Aspergillus parasiticus; Aspergillus bombycis, Aspergillus ochraceoroseus, Aspergillus nomius, and Aspergillus pseudotamari

Possess toxicity and carcinogenicity. Disease called aflatoxicoses can cause death in acute case, chronic aflatoxicosis results in cancer & immune suppression. Liver is primary targeted organ.

Citrinin
First isolated from Penicillium citrinum.Also from species of Aspergillus, strains of Penicillium camemberti (used to produce cheese) and Aspergillus oryzae. Monascus ruber and Monascus purpureus ( industrial species used to produce red pigments).

Significance for human health is unknown.

Ergot Alkaloids
Sclerotia of Claviceps species(common pathogens of grass species)

The principal animals at risk are cattle, sheep, pigs, and chickens. Clinical symptoms of ergotism in animals include gangrene, abortion, convulsions, suppression of lactation, hypersensitivity, and ataxia.

Fumonisins
Fusarium verticillioides (formerly Fusarium moniliforme = Gibberella fujikuroi), Fusarium proliferatum, Fusarium nygamai, and Alternaria alternata f. sp. lycopersici

Probable link with esophageal cancer in human. Acute exposure to fumonisin B1 may cause abdominal pain, borborygmus, and diarrhea. neural tube defects in experimental animals

Ochratoxin
Aspergillus ochraceus, Aspergillus alliaceus, Aspergillus auricomus, Aspergillus carbonarius, Aspergillus glaucus, Aspergillus melleus, and Aspergillus niger, Penicillium verrucosum(common contaminant of barley)

Kidney is primary target organ. Ochratoxin A is a liver toxin, an immune suppressant, a potent teratogen, and a carcinogen. It inhibits the enzyme in synthesis of phenylalanine-tRNA complex and also inhibits mitochondrial ATP production and stimulates lipid peroxidation. European Union Scientific Committee recommended that ochratoxin A levels be reduced to below 5 ng/kg of body weight per day.

Patulin
Mold species. Penicillium patulum (later called Penicillium urticae, now Penicillium griseofulvum), Penicillium expansum

Toxic at high concentration in laboratory settings, but evidence for natural poisoning is indirect and inconclusive. Joint Food and Agriculture Organization-World Health Organization Expert Committee on Food Additives: maximum tolerable daily intake for patulin of 0.4 mg/kg of body weight per day

Trichothecenes
fungal genera, including Fusarium, Myrothecium, Phomopsis, Stachybotrys, Trichoderma, Trichothecium

Consumption result in alimentary haemorrhage and vomiting; direct contact causes dermatitis. It’s extremely potent inhibitors of eukaryotic protein synthesis.

Zearalenone

Fusarium graminearum

recommended safe human intake: 0.05 μg/kg of body weight per day

Reference: http://www.nzfsa.govt.nz/science/data-sheets/index.htm

Grayanotoxin in honey

Name of toxin: Grayanotoxin (formerly known as andromedotoxin, acetylandromedol, and rhodotoxin)

Nature of acute disease: Honey intoxication caused by the consumption of honey produced from the rhododendrons nectar. Grayanotoxins is the cause of intoxication.

Symptom of disease: Excess salivation, perspiration, vomiting, dizziness, weakness and paresthesia are some of the symptom found. At more serious level, loss of coordination, progressive muscular weakness, bradycardia and nodal rhythm or Wolff-Parkinson-White syndrome may present.

Food analysis: Isolation of grayanotoxins from the suspect commodity can be done by typical extraction procedures for naturally occurring terpenes. Thin layer chromatography used for grayanotoxin identification.

Reference: http://en.wikipedia.org/wiki/Food_poisoning
http://www.cfsan.fda.gov/~mow/chap44.html

Package 2 kick off!

Hi dear all:
Are all of u free on Sat night? Can we meet at 10pm? Please confirm by this coming thurs 12am if possible. Thx! =) Meantime, wuld like to highlight the reserch all of us shuld give prior first:

Me: 1.Identify toxins found in ice crean containing milk and honey.
2.Sources & toxicity of major food toxins.(i.e. Aflatoxin by aspergillus flavus)

Val: Type of toxins produced by pathogens. (i.e.Shiga toxin by E.coli)

Fresa& LiXing: 1.Principles of various lab techniques used in toxins detection.
2.Legal limit on all identified toxins.{more toxins may be identified later, but for sure thr'r aflatoxin(focus M1, B1, B2, G1, G2 oni) and orchratoxin, find on these 2 first}

Shu Jun & Shu Wen: 1.Main principles used in GM process.
2.Advantage & disadvantage of GM foods.

Whether o not we meet in this week, please send me or post a summary and oth related details on BB for above finding by 28june,this coming Sat 12am. Many many thx! =)

Recent Salmonella outbreak in USA raw tomatoes!

According to the Food and Drug Administration (FDA), 145 to 150 people in USA who were suspected to had consumed raw red tomatoes, have been sickened by salmonellosis. 25 hospitalizations were reported but there is no death. The microbe strain that cause this crisis is Salmonella Saintpaul. So far, the source of contaminated tomatoes has not yet been found. FDA is collaborating with the Centers for Disease Control and Prevention in order to work on traceability.

Salmonellosis in healthy people can cause fever, diarrhea (which can be bloody), nausea, vomiting and abdominal cramps 6 to 72 hours after infection. Generally, the illness lasts 3 to 7 days. However, dehydration may occur following severe diarrhea . To get hydrated, the victims may receive intravenous fluids and medication may be given to provide symtomatic relief. In severe cases, antibiotics are needed for treatment if Salmonella infection spread from intestine to the blood stream nad eventually cause death. The elderly, infants, and people with impaired immune system are more prone to Salmonellosis. Some people afflicted with it later experience reactive arthritis, which can have long-lasting, disabling effects.

References :
http://www.time.com/time/nation/article/0,8599,1814553,00.html
http://www.usatoday.com/news/health/2008-06-08-tomatoes_N.htm

The bacteria in our gut – Clostridium Difficile ( C. Diff. )

A gram-positive, anaerobic, and spore-forming rods bacteria which cause the severe infection of colon called pseudomembranous colitis. The illness is characterized by offensive-smelling diarrhea, fever, and aabdominal pain. It can cause toxic megacolon or even fatal.

According to an article published by Centre for Disease Control (CDC), there is a vast increment of people being hospitalized resulted from C. Diff. infection. Feces spores are the spreading medium and it’s hardly killed by conventional cleaners or antibacterial soap.

Besides, when patient take in antibiotic which works against colon bacteria, C.Diff. explodes as it is resistant to them. Virulent strain of C.Diff. is commonly found only after 2000.

Misuse of antibiotics and patients who are older and sicker are factors that cause the rising of C.Diff. infection.

A research is conducted based on more than 36 million annual discharges from non-governmental U.S. hospitals. It is to be concluded that fatal cases account for 2.3 percent or 5,500 death in other word.

Frequency of occurrence and preventive measures of C. Diff. infection are being studied by the Association for Professionals in Infection Control and Epidemiology in order to come out with a best solution.

Reference available at CDC publication: http://www.cdc.gov/ncidod/EID/index.htm

Health risk associated in star fruit!

Fruits always come along with 'healthy' and 'nutritious' in many people's mind. However, kidney failure patient may fell into a state of unconscious if star fruit is being ingested. This is what happened to a dialysis patient who is hospitalised in Intensive Care Unit after consuming star fruit. The news was found in The Star newspaper.

Ingestion of star fruit led to neurological disturbances, including hiccups, mental confusion, and even death! This is due to presence of oxalic acid and the neurotoxic effects of star fruit intoxication in mostly dialysed patients with chronic renal failure.

Say no to synthetic colouring!

Synthetic colourings are being used in food industry extensively. They are commonly found in confectionery products, ice cream, bakery products, cakes, and soft drinks. Foods may seems more colourful and attractive after coated or dyed with those 'rainbows'. However, the long term effect that synthetic colourings jeopardize our body is undeniable!

Recently read the news reported that European countries are urged to ban the use of additives in 'purely cosmetic' ingredients and foods. The colours involved are tartrazine (E 102), quinoline yellow (E 104), sunset yellow (E 110), carmoisine (E 122), ponceau 4R (E 124) and allura red (E 129). Manufacturers are encouraged to suspend the usage of these colouring and seek for alternatives.

Same goes with UK Food Standards Agency (FSA) board who decided to mandate UK manufacturers not to use these colourings and giving advice to parents on intake of synthetic colourings. However, while some industry members agree and support the action , some others claim that voluntary reformulation was underway but forcing could put unnecessary pressure and costs on them.

Representatives from other bodies such as Consumers' Association of Ireland, Friends of the earth, The Danish Ecological Council, the International Obesity Task Force, The Soil Association
and the UK Food Commision said that the Southampton study gives valid reasons to suggest that there is an appreciable risk associated with these colourings. Furthermore, dyes serve no purpose but to colour foods.

In conclusion, renewed calls for European ban on Southampton additives is in need to be implemented. All parties involved should commit their highest cooperation whenever possible in compliance with local legislation.

Article available at: http://www.foodproductiondaily.com/news/ng.asp?id=84636