Shariful Islam Z Mycntoxin

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<ul><li><p>8/3/2019 Shariful Islam Z Mycntoxin</p><p> 1/13</p><p>Mycotoxins are secondary metabolites produced by microfungi that are capable of</p><p>causing disease and death in humans and other animals. Because of their pharmacological</p><p>activity, some mycotoxins or mycotoxin derivatives have found use as antibiotics, growthpromotants, and other kinds of drugs; still others have been implicated as chemical</p><p>warfare agents. This review focuses on the most important ones associated with human</p><p>and veterinary diseases, including aflatoxin, citrinin, ergot akaloids, fumonisins,ochratoxin A, patulin, trichothecenes, and zearalenone.</p><p>\Rapid screening of animal feeds for mycotoxins and Salmonella contaminations.</p><p>Mycotoxins and Salmonella are described as major and well known safety risks linked to</p><p>animal feed and subsequently the human food chain. This chapter considers methods for</p><p>the detection of mycotoxins and Salmonella in animal feeds with particular attention torapid methods. Examples of validated methods for mycotoxins are summarised; and rapid</p><p>methods for the detection of aflatoxins fumonisins ochratoxins deoxynivalenol andzearalenone are shown.</p><p>The following summary of toxins and their targets is adapted from Smith and Moss</p><p>(1985), with a few additions from the more recent literature. While this compilation of</p><p>effects does not describe the effects from multiple exposures, which could includesynergistic effects, it does give a better idea of possible results of mycotoxin exposure to</p><p>multiple molds indoors.</p><p> Vascular system (increased vascular fragility, hemorrhage into body tissues, orfrom lung, e. g. , aflatoxin, satratoxin, roridins).</p><p> Digestive system (diarrhea, vomiting, intestinal hemorrhage, liver effects, i. e. ,</p><p>necrosis, fibrosis: aflatoxin; caustic effects on mucous membranes: T-2 toxin;</p><p>anorexia: vomitoxin. Respiratory system: respiratory distress, bleeding from lungs e. g. ,</p><p>trichothecenes.</p><p> Nervous system, tremors, incoordination, depression, headache, e. g. , tremorgens,trichothecenes.</p><p>Cutaneous system : rash, burning sensation sloughing of skin, photosensitization,e. g. , trichothecenes.</p><p> Urinary system, nephrotoxicity, e. g. ochratoxin, citrinin.</p><p> Reproductive system; infertility, changes in reproductive cycles, e. g. T-2 toxin,</p><p>zearalenone.</p><p> Immune system: changes or suppression: many mycotoxins.</p></li><li><p>8/3/2019 Shariful Islam Z Mycntoxin</p><p> 2/13</p><p>Some Common Mycotoxins and the Organisms that Produce Them</p><p>Mycotoxin Organism</p><p>Acetoxyscirpenediol Fusarium moniliforme, F. equiseti, F. oxysporum, F.culmorum, F. avenaceum, F. roseum, and F. nivale</p><p>Acetyldeoxynivalenol Fusarium moniliforme, F. equiseti, F. oxysporum, F.</p><p>culmorum, F. avenaceum, F. roseum, and F. nivale</p><p>Acetylneosolaniol Fusarium moniliforme, F. equiseti, F. oxysporum, F.</p><p>culmorum, F. avenaceum, F. roseum, and F. nivale</p><p>Acetyl T-2 toxin Fusarium moniliforme, F. equiseti, F. oxysporum, F.</p><p>culmorum, F. avenaceum, F. roseum, and F. nivale</p><p>Aflatoxin Aspergillus flavus, A. parasiticus</p><p>Aflatrem Aspergillus flavus</p><p>Altenuic acid Alternaria alternata</p><p>Alternariol Alternaria alternata</p><p>Austdiol Aspergillus ustus</p><p>Austamide Aspergillus ustus</p><p>Austocystin Aspergillus ustus</p><p>Avenacein +1 Fusarium moniliforme, F. equiseti, F. oxysporum, F.</p><p>culmorum, F. avenaceum, F. roseum, and F. nivale</p><p>Beauvericin +2 Fusarium moniliforme, F. equiseti, F. oxysporum, F.</p><p>culmorum, F. avenaceum, F. roseum, and F. nivale</p><p>Bentenolide Monographella nivalisBrevianamide Aspergillus ustus</p><p>Butenolide Fusarium moniliforme, F. equiseti, F. oxysporum, F.</p><p>culmorum, F. avenaceum, F. roseum, and F. nivale</p><p>Calonectrin Fusarium moniliforme, F. equiseti, F. oxysporum, F.culmorum, F. avenaceum, F. roseum, and F. nivale</p><p>Chaetoglobosin Chaetomium globosum</p><p>Citrinin Aspergillus carneus, A. terreus, Penicillium citrinum, P.</p><p>hirsutum, P. verrucosum</p><p>Citreoviridin Aspergillus terreus, Penicillium citreoviride</p><p>Cochliodinol Chaetomium cochliodes</p><p>Crotocin Acremonium crotocinigenum</p><p>Cytochalasin E Aspergillus clavatus</p><p>Cyclopiazonic acid Aspergillus versicolor</p></li><li><p>8/3/2019 Shariful Islam Z Mycntoxin</p><p> 3/13</p><p>Aflatoxin</p><p>Aflatoxin is one of the most potent carcinogens known to man and has been</p><p>linked to a wide variety of human health problems. The FDA has establishedmaximum allowable levels of total aflatoxin in food commodities at 20 parts per</p><p>billion. The maximum level for milk products is even lower at 0. 5 parts perbillion. Primarily Aspergillus species fungi produce aflatoxin.</p><p>Ochratoxin</p><p>Ochratoxin is primarily produced by species of Penicillium and Aspergillus.Ochratoxin is damaging to the kidneys and liver and is also a suspected</p><p>carcinogen. There is also evidence that it impairs the immune system.</p><p>T-2 Toxin</p><p>T-2 Toxin is a tricothecene produced by species of Fusarium and is one of themore deadly toxins. If ingested in sufficient quantity, T-2 toxin can severely</p><p>damage the entire digestive tract and cause rapid death due to internal</p><p>hemorrhage. T-2 has been implicated in the human diseases alimentary toxic</p><p>aleukia and pulmonary hemosiderosis. Damage caused by T-2 toxin is oftenpermanent.</p><p>Fumonisin</p><p>Fumonisin is a toxin associated with species of Fusarium. Fumonisin is</p><p>commonly found in corn and corn-based products, with recent outbreaks of</p><p>veterinary mycotoxicosis occurring in Arizona, Indiana, Kentucky, NorthCarolina, South Carolina, Texas and Virginia. The animals most affected were</p><p>horses and swine, resulting in dozens of deaths. Fumonisin toxin causes "crazyhorse disease", or leukoencephalomalcia, a liquefaction of the brain. Symptoms</p><p>include blindness, head butting and pressing, constant circling and ataxia,</p><p>followed by death. Chronic low-level exposure in humans has been linked to</p><p>esophageal cancer. The American Association of Veterinary LaboratoryDiagnosticians (AAVLD) advisory levels for fumonisin in horse feed is 5 PPM.</p><p>Vomitoxin or Deoxynivalenol(DON)</p><p>Vomitoxin, chemically known as Deoxynivalenol, a tricothecene mycotoxin, isproduced by several species of Fusarium. Vomitoxin has been associated withoutbreaks of acute gastrointestinal illness in humans. The FDA advisory level for</p><p>vomitoxin for human consumption is 1ppm.</p><p>Zearalenone</p></li><li><p>8/3/2019 Shariful Islam Z Mycntoxin</p><p> 4/13</p><p>New spectroscopic insights for the identification of mycotoxins in cerealsMycotoxins are toxic fungal metabolites that may contaminate primary food productssuch as</p><p>cereals, nuts and fruits. The most predominant mycotoxins in Europe among others are</p><p>the</p><p>Aflatoxins and Ochratoxinsproduced by storage fungis, such asAspergillus andPenicillium</p><p>species, and Toxins from field-borneFusarium species, for exampleZearalenone andDeoxynivalenol. [1]</p><p>Introduction</p><p>Mycotoxins are toxic metabolises produced by fungi, especially by saprophytic moulds</p><p>growing on foodstuffs or animal feeds. They must always have been a hazard to man anddomestic animals, but until the past 30 years their effects have been largely overlooked.</p><p>Although poisonous mushrooms are carefully avoided, moulds growing on foods havegenerally been considered to cause unaesthetic spoilage, without being dangerous tohealth. Between 1960 and 1970 it was established that some fungal metabolises, now</p><p>called mycotoxins, were responsible for animal disease and death. In the decade</p><p>following 1970 it became clear that mycotoxins have been the cause of human illness and</p><p>death as well, and are still causing it.</p><p>Acute mycotoxicoses</p><p>Table 1 lists a number of mycotoxins, some of the moulds which are known to produce</p><p>them, and known or possible acute diseases with which they may be involved. In some</p><p>cases, the connection between mycotoxin and disease is fairly well documented. In other,cause and effect are less certain. The most important disease which may have been due to</p><p>mycotoxins, are reviewed briefly below</p><p>Chronic mycotoxicoses</p><p>Some of the toxins discussed in this section (Table 2) may produce acute effects, but theyare more significant because of their ability to cause long term disease. The best known</p><p>and most studied of chronic mycotoxicoses are produced by aflatoxins.</p><p>Aflatoxins</p><p>Aflatoxins were discovered in 1960 following the deaths of 100,000 young turkeys in</p><p>England, and high incidences of liver disease in ducklings in Kenya and hatchery rearedtrout in the United States, English scientists soon established the cause of all these</p><p>problems to be toxins produced by the common moulds Aspergillus flavus and A.</p><p>parasiticus. Assay techniques were devised and preliminary toxicological studies carriedout by 1963 (Sargent et al., 1963).</p></li><li><p>8/3/2019 Shariful Islam Z Mycntoxin</p><p> 5/13</p><p>Aflatoxins and primary liver cancer</p><p>Scarcely two years after the discovery of aflatoxins came the first warnings that they may</p><p>cause human liver cancer. This disease has a high incidence in central Africa and SouthEast Asia. When epidemiological evidence suggested a possible correlation with</p><p>mycotoxins in the food supply, field studies were initiated on an international basis.Epidemiological data were coupled with analyses of those foods that form the staple diets</p><p>of stable indigenous populations. Stability in both diet and population is essential instudies of this kind because of the long induction period (10-20 years) for human liver</p><p>cancer.</p><p>Mycotoxins and human health risks an overview</p><p>This is a review and brief historical report of mycotoxins as risks to human health.Mycotoxins are recorded in history as far back as 5,000 years ago in China. Besides ergot</p><p>and mushroom poisonings, reports as early 1861, indicate that a suspected mycotoxin</p><p>affecting humans was reported in Russia, and 1891, there was a report of mouldy rice inJapan to be toxic to man. This review reports on the early literature on mycotoxins</p><p>affecting human up to 1960, which is the time of the discovery of aflatoxin, and to our</p><p>present knowledge where this problem still persists.</p><p>Mycotoxin economic aspects</p><p>Thailand is an agricultural country. Agriculture has played a vital role in the Thai</p><p>economy contributing around 25% of the gross domestic product (GDP) and about 55%of export by value.</p><p>Thailand's economy still depends on the successful export of its major agricultural</p><p>commodities. Problems in export of agricultural products are many and varied.</p><p>Firstly, it subjects to the uncertainty of the world commodities market including the</p><p>importing policy of the buying country.</p><p>Sampling, sample handling and preparation in grains</p><p>and cereals</p><p>SAMPLING</p><p>By the result of some sort of a test of a portion of the material with its quality criterion to</p><p>judge whether each article is non-defective or defective, or with an acceptability criterion</p><p>to judge whether a lot is acceptable or not, the portion of the material in a sample used to</p></li><li><p>8/3/2019 Shariful Islam Z Mycntoxin</p><p> 6/13</p><p>judge the whole material, improper sampling will lead to inappropriate grading even with</p><p>correct testing.</p><p>n general, sampling is conducted in such away that the sample represents the population,but in the same case a sample is taken from an especially good or bad section. Without</p><p>understanding the sampling method of the test sample, one can not evaluate correctlyabout the quality of the material being inspected.</p><p>Uniform sampling</p><p>In this method, a sample is taken so as to represent the average of the whole population.</p><p>Samples are taken in a small quantity from each section of the population. In this case,</p><p>the total amount of the sampling method of the test sample, one cannot of it is used for</p><p>testing. Sampling in this case has to be evenly reduced. The reduction procedure is calleddividing, which is performed by quartering, dividing or the use of divider.</p><p>Selective sampling</p><p>When the products are disposed according to the lowest quality, sampling is made fromsections with particularly poor quality. For example, to judge baking condition of bread</p><p>through determination of moisture a sample is taken from the central part of the bread.</p><p>Random sampling</p><p>This method is applied in cases of the several samples are taken from a product to beuniform and when they do not have the same quality. In this sampling, individual</p><p>samples, an amount of sampling, and in some case, sampling period are not fixed before</p><p>sampling. Strictly random sampling is rather difficult, and so the subjects of sampling are</p><p>chosen by the use of dice, lottery, or random table. The random sampling can preventunfair action of inspect.</p><p>AMPLING, SAMPLE HANDLING IN GRAIN AND CEREALS (ISO)</p><p>Correct sampling is an operation that requires most careful attention. Emphasis cannot</p><p>therefore be too strongly laid on the necessity of obtaining a properly representativesample of grain. Careless or inaccurate sampling could lead to misunderstanding and</p><p>unwarranted financial adjustments.</p><p>Samples shall be fully representative of the lots from which they are taken. Therefore, as</p><p>the composition of the lot is seldom uniform, a sufficient number of increments shall betaken and carefully mixed, thus giving a bulk sample from which are obtained, by</p><p>successive divisions, the laboratory samples.</p><p>Apparatus</p><p>Apparatus is required as follows, and many types and variations of apparatus are</p><p>available.</p></li><li><p>8/3/2019 Shariful Islam Z Mycntoxin</p><p> 7/13</p><p>Prevention and control of mycotoxins</p><p>STRATEGIES FOR PREVENTION AND CONTROL OF MYCOTOXINS</p><p>To design strategies for the reduction or elimination of mycotoxins, knowledge abouttheir fungal sources are needed. The growth of fungi in crops and agricultural products is</p><p>the main cause of toxin formation and related to the concentration of the toxic substances.</p><p>Many factors are involved in enhancing the formation of mycotoxins. They are plantsusceptibility to fungi infestation, suitability of fungal substrate, temperate climate,</p><p>moisture content and physical damage of seeds due to insects and pests.</p><p>Toxin-producing fungi may invade at pre-harvesting period, harvest-time, during post-</p><p>harvest handling and in storage. According to the site where fungi infest grains,toxinogenic fungi can be divided into three groups: (a) field fungi; (b) storage fungi; and</p><p>(c) advanced deterioration fungi. The first category includes species of plant pathogenic</p><p>fungi, namely, genus Fusarium, e.g. F. moniliforme, F roseus, F. tricinctum and F. nivale.The "storage fungi" are principally the general Aspergillius and Penicillium, e.g. A.</p><p>flavus and A. parasiticus. The "advanced deterioration fungi" normally do not infest</p><p>intact grains but easily attack damaged ones and require high moisure content. Theexamples of the third group are A. clavatus, A. fumigatus, Chaetomium, Scopulariopsis,</p><p>Rhizopus, Mucor, and Absidia.</p><p>The prevention of mycotoxins in our environment is a big task. In general, prevention of</p><p>the contamination of fungi and their mycotoxins in agricultural commodities can bedivided into these following three levels.</p><p>1. Primary prevention</p><p>The step of prevention should be initially carried out before the fungal infestation and</p><p>mycotoxin contamination. This level of prevention is the most important and effectiveplan for reducing fungal growth and mycotoxin production. Several practic...</p></li></ul>