SEARCH · PubMed Health

Results for “Mycotoxin”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 865 records · Page 48Linked to original sources

PubMed1986

Pharmacological effects of the tremorgenic mycotoxin fumitremorgin A.

Some pharmacological effects of a potent tremorgenic mycotoxin, fumitremorgin A (FTA), on the rabbit were studied. FTA (10-200 micrograms/kg, i.v.) caused clonic and tonic convulsion accompanied by nystagmus and miosis in conscious rabbits, after a latent period. Even in decorticated or decerebrated rabbits, FTA (100-200 micrograms/kg, i.v.) could induce violent motor effects similar to those observed in conscious rabbits. Under light anesthesia with urethane and chloralose, a higher dosage (more than 100 micrograms/kg) was needed to cause clonic and tonic convulsion. FTA facilitated phrenic nerve discharges as well as efferent discharges of the vagal nerve and the cervical sympathetic nerve. Hypertension induced by FTA was inhibited by phentolamine, while bradycardia and arrhythmia caused by this toxin was abolished by atropine or bilateral vagotomy. The electroencephalogram showed persistent strong arousal response after intravenous injection of FTA. A seizure pattern was never observed. It was suggested that the main site of action of FTA was in the brain stem.

Anesthesia↗

PubMed1990

Central effects of the neurotropic mycotoxin fumitremorgin A in the rabbit. (II). Effects on the brain stem.

In order to determine the main site of the convulsant action of the neurotropic mycotoxin fumitremorgin A, the role of the brain stem reticular formation was studied. In rabbits lightly anesthetized with urethane and chloralose, electrical stimulation of the reticular formation elicited burst discharges in the common peroneal nerve and in the tibial nerve. This facilitatory effect of electrical stimulation was markedly potentiated by intravenous administration of a small dose of FTA, before onset of actual convulsion. Under the influence of FTA, a remarkable increase in the spontaneous electrical activity of the midbrain reticular formation was observed. The firing pattern of some neurons in the reticular formation corresponded very well with abnormal burst discharges in the common peroneal nerve. These effects of FTA were inhibited by chlorpromazine (0.1-1.0 mg/kg, i.v.), diazepam (0.1-1.0 mg/kg, i.v.), mephenesin (5-10 mg/kg, i.v.) and pentobarbital (5-15 mg/kg, i.v.). It was concluded that FTA might activate some neurons in the midbrain reticular formation and that convulsive burst discharges in peripheral motor nerves resulted from abnormal activation of these neurons, although the role of the medullary reticular formation could not be excluded.

Animals↗

PubMed1974

Mycotoxins: toxicity, carcinogenicity, and the influence of various nutritional conditions.

Toxicologic diseases of man and animals, associated with molds growing on foods, have been recognized for centuries. Only in recent years, however, have these mycotoxicoses received the attention of many laboratories and skilled scientists around the world in a broad inter-disciplinary effort. This review covers the literature on mycotoxicoses but centers on those about which most is known, particularly the diseases associated with metabolites elaborated by some strains of Aspergilli, Penicillia, Fusaria, Stachybotrys, and Claviceps. The ubiquitous nature of the aflatoxins, toxic metabolites produced by Aspergillus flavus, make them important to public health, especially since it is now known that certain areas of endemic liver disease coincide with consumption of aflatoxins and, often, malnutrition. The older disease of ergotism, the scourge of Europe for centuries, is considered in detail. Alimentary toxic aleukia, which has caused enormous suffering in Russian human and animal populations, is better understood as a result of relatively recent experimental investigations. Stachybotryotoxicosis, a disease previously considered to be of significance only to man has now been identified in domestic animals.Finally, Japanese studies have clearly revealed the hepatotoxicity of certain metabolites of Penicillium molds. Factors that influence susceptibility to mycotoxins and the hazards they present to man are also reviewed.

Aflatoxins↗

PubMed1977

Mycotoxin tolerances in foodstuffs.

In most countries general legislation on food (and feed) prohibits the sale of products containing poisonous or harmful substances, which would include relevant mycotoxins as well. So far only aflatoxin has been dealt with specifically in legislation. The aflatoxin control may include all foods (and feeds) but is limited in most countries to certain commodities likely to be heavily contaminated, viz. oilseeds and derived products. The aflatoxin tolerances established for foods vary from zero (level set by analytical method) through 30 ppb to 50 ppb. Tolerances for feeds are generally higher.

Aflatoxins↗

PubMed1977

Short-term tests and mycotoxins.

Naturally-occurring fungal metabolites, such as aflatoxins and sterigmatocystin, are specific examples of toxic and hepatocarcinogenic environmental contaminants which are active in Fish, Birds, Mammals and, probably, Man. The biological potency of these substances has led to a search for other carcinogenic fungus-derived products. As screening techniques for selecting compounds to be tested for their genetic and carcinogenic potency in animals, various short-term tests can be currently utilized. The use of mutagenesis, DNA repair, chromosomal aberrations, cell transformation, cytological alterations and reaction with nucleic acids in vivo or in vitro as end-points in short-term tests to detect potential chemical carcinogens will be presented. Based on recent data in the literature and from our own research activities, 2 major aspects of various short-term tests will be critically reviewed: a. their predictive value, in order to assess the possible carcinogenic risk of mycotoxins, and b. their utility to investigate the mechanism of metabolic activation of these chemicals in Mammals and in Man.

Animals↗

PubMed2002

Methods and method evaluation for mycotoxins.

Mycotoxins are metabolites of molds frequently found on and in agricultural commodities, food and feeds. Owing to their demonstrated acute, sub-acute and, in some cases, chronic toxicity, an effort has been made, worldwide, to control human and animal exposure to these toxic chemicals. This effort depends upon the availability of validated analytical methods for their detection and quantitation. This paper outlines the methodology available, and the procedures used to validate, i.e. evaluate, these methods based on the use of interlaboratory collaborative studies and the application of the HORRAT.

Animal Feed↗

PubMedDate not supplied

Biosynthesis of trichothecene mycotoxins in Fusarium culmorum cultures.

A high yielding production of the trichothecene mycotoxin 3-acetyldeoxynivalenol (3-AcDON) in cultures of Fusarium culmorum is described. By supplying [14C]acetate, 14C-labelled 3-AcDON suitable for further metabolic studies has been obtained. The pattern of labelling has been ascertained by using 13C-labelled acetate precursors, and is in line with established biosynthetic data. A second trichothecene produced in significant amounts by F. culmorum has been identified as 3 alpha, 15-diacetoxy-7 alpha, 8 alpha-dihydroxy-12, 13-epoxytrichothec-9-ene (7 alpha, 8 alpha-dihydroxycalonectrin).

Chemical Phenomena↗

PubMedDate not supplied

Trichothecene mycotoxins from Fusarium culmorum cultures.

Chemical analysis of the culture filtrates of Fusarium culmorum CMI 14764 has demonstrated the presence of seven trichothecene mycotoxins. Major metabolites are 3-acetyldeoxynivalenol and 7 alpha, 8 alpha-dihydroxycalonectrin, with 3,15-diacetyldeoxynivalenol, deoxynivalenol, calonectrin, isotrichodermin and 12,13-epoxytrichothec-9-ene (EPT) as minor products. The occurrence of the rarely encountered unsubstituted trichothecene EPT is significant in that this compound may function as a common intermediate in the biosynthetic pathways to all natural trichothecenes. The structures of the known trichothecenes isolated from F. culmorum suggest a route in which EPT is sequentially oxygenated to the more complex deoxynivalenol derivatives.

Culture Media↗

PubMed2001

Phytotoxicity of pathogenic fungi and their mycotoxins to cereal seedling viability.

Aspergillus flavus, Alternaria alternata and Fusarium oxysporum were found to be the pathogenic fungi mostly reducing cereal (barley, sorghum and wheat) seedlings. The pathogens have the ability to produce aflatoxin B1 and G1, diacetoxyscirpenol, kojic acid and tenuazonic acid that reduced seedling viability. The inhibition dose for 50% reduction (LD50) was recorded by aflatoxins at 0.83 mg L-1 for barley, 1.74 mg L-1 for wheat and 2.75 mg L-1 for sorghum. Diacetoxyscirpenol produced its inhibition at 1.26 mg L-1 for barley, 3.98 mg L-1 for wheat and 10 mg L-1 for sorghum. Kojic acid induced 50% inhibition at 63 mg L-1 for barley, 105 mg L-1 for wheat and 251 mg L-1 for sorghum. However, tenuazonic acid was less toxic where, the toxicity was ranged between 79-550 mg L-1. The inhibition in germination was more pronounced in barley followed by wheat and negligible in sorghum to all tested mycotoxins. This inhibition attributed to the reduction in seedling amylase activity. Amylase was also reduced in the same trend: barley > wheat > sorghum. Grain treatment with carboxin-captan and thiophanatemethyl-thiram at 1 g kg-1 grain increased seedlings vigour of wheat in sterilized soil by 45 and 22%, barley by 24 and 33% and sorghum by 15 and 30%, respectively. These fungicides have also a positive effect on cereal when soil was inoculated with A. flavus, A. alternata and F. oxysporum.

Amylases↗

PubMed2007

Sensitive detection of estrogenic mycotoxin zearalenone by open sandwich immunoassay.

Zearalenone (ZEA) is an estrogenic mycotoxin produced by Fusarium sp., and its production on corn and small grains during storage has been of considerable concern. For sensitive ZEA detection, we applied an open sandwich (OS) immunoassay that can noncompetitively detect monovalent antigens utilizing an antigen-induced enhancement of the V(H)/V(L) interaction. We cloned the V(H) and V(L) cDNAs of anti-ZEA mAb to a split-Fv phagemid pKST2, and firstly both V(H) and V(L) fragments were displayed on M13 phage p9 and p7, respectively, using an amber suppressor, TG-1, as a host. The split-Fv phage showed specific binding to immobilized ZEA, which was well inhibited by free ZEA. Then, the V(H)/V(L) interaction and its antigen-dependency were analyzed using a non-suppressor HB2151 as a host to produce V(H)-displaying phage and his/myc-tagged soluble V(L) in the culture supernatant. By capturing V(L) with an anti-myc or -his antibody and probing bound V(H)-phage, ZEA was successfully detected with a superior detection limit as well as a wider working range than those of a competitive assay. Also, essentially the same results were reproduced with purified V(H)-alkaline phosphatase and MBP-V(L) fusion proteins.

Amino Acid Sequence↗

PubMed1990

Biological reactive intermediates of bisfuranoid mycotoxins.

Based on the mode of action of AFB1 and the activities of its biologically active intermediates, one may conclude that: 1. The mode of toxic action of the bisfuranoid mycotoxin is through epoxidation of the vinyl ether double bond of their dihydrobisfuran functionality. 2. The DNA and plasma albumin adducts formed in vivo may be useful in the molecular dosimetry of these environmental carcinogens. 3. Monitoring of these adducts of AFB1 in biological samples so far indicates that aflatoxin is likely involved in the etiology of human liver cancer.

Aflatoxin B1↗

PubMed2003

Toxic mold and mycotoxins in neurotoxicity cases: Stachybotrys, Fusarium, Trichoderma, Aspergillus, Penicillium, Cladosporium, Alternaria, Trichothecenes.

Presented is the argument that psychologists and neuropsychologists have no scientific basis for rendering opinions about causation given the current state of the literature. The critical question is whether in a residence or office inhalation of mold spores or mold metabolites, including mycotoxins, causes neuropsychological impairment or mental and emotional disorders. There has not been sufficient research to support such conclusions. Nonetheless, in the context of litigation, speculative opinions are rendered in lieu of scientifically well-founded conclusions. Resources for recognizing and coping with pseudoscientific arguments are suggested.

Alternaria↗

PubMed1995

Endogenous toxins and mycotoxins in forage grasses and their effects on livestock.

Plant toxins are the chemical defenses of plants against herbivory. Grasses have relatively few intrinsic toxins, relying more on growth habit to survive defoliation and endophytic fungal toxins as chemical defenses. Forage grasses that contain intrinsic toxins include Phalaris spp. (tryptamine and carboline alkaloids), sorghums (cyanogenic glycosides), and tropical grasses containing oxalates and saponins. Toxic effects of these grasses include neurological damage (Phalaris staggers), hypoxia (sudangrass), saponin-induced photosensitization (Brachiaria and Panicum spp.), and bone demineralization (oxalate-containing grasses). Endophytic toxins in grasses include ergot alkaloids in tall fescue and tremorgens (e.g., lolitrem B) in perennial ryegrass. Lolitrems cause neurological effects, producing the ryegrass staggers syndrome. Annual ryegrass toxicosis is caused by corynetoxins, which are chemically similar to tunicamycin antibiotics. Corynetoxins are produced by Clavibacter bacteria that parasitize a nematode, Anguina agrostis, that may infect annual ryegrass. Corynetoxins inhibit glycoprotein synthesis, causing defective formation of various blood components of the reticulo-endothelial system. Another mycotoxin in ryegrass is sporidesmin, which causes liver damage and secondary photosensitization (facial eczema). Fusarium toxins such as zearalenone and trichothecenes also occur in forage grasses. Kikuyugrass poisoning results in severe damage to the ruminal epithelium and omasal mucosa, and neurological signs. The causative agent, which may be associated with army worm predation of the grass, has not been identified. The properties and significance of these toxins are reviewed.

Acremonium↗

PubMed1997

Effect of feeding blends of Fusarium mycotoxin-contaminated grains containing deoxynivalenol and fusaric acid on growth and feed consumption of immature swine.

Experiments were conducted to determine the effect of feeding diets containing combinations of the Fusarium metabolites deoxynivalenol (DON) and fusaric acid (FA) to starter swine. In all experiments, pigs of approximately 8.2 kg initial weight were fed diets containing blends of mycotoxin-contaminated corn, wheat, and barley for 21 d with growth and feed consumption determined weekly. In the first experiment, diets were determined to contain 0 microgram DON/g + 58.9 micrograms FA/g (control), 4.4 micrograms DON/g + 57.1 micrograms FA/g, 6.0 micrograms DON/g + 48.6 micrograms FA/g, and 7.5 micrograms DON/g + 57.4 micrograms FA/g. The feeding of all diets containing DON caused significant linear depressions in growth and feed intake after only 1 wk. Lower concentrations of DON and FA were fed in the second experiment with diets containing 0 microgram DON/g + 16.3 micrograms FA/g (control), .5 microgram DON/g + 14.3 micrograms FA/g, 1.1 micrograms DON/g + 14.1 micrograms FA/g, and 1.9 micrograms DON/g + 13.6 micrograms FA/g. There was a significant linear reduction in feed intake after 1 wk with increasing levels of dietary DON. Weight gains declined significantly only after 3 wk. Increasing amounts of FA combined with relatively constant amounts of DON were fed in the third experiment. By analysis, diets contained .5 micrograms DON/g + 2.9 micrograms FA/g (control), 2.2 micrograms DON/g + 12.2 micrograms FA/g, 2.5 micrograms DON/g + 15.6 micrograms FA/g, and 2.4 micrograms DON/g + 15.9 micrograms FA/g. In the 1st wk, the feeding of increasing amounts of fusaric acid combined with a relatively constant amount of DON caused a significant linear depression in weight gain. We concluded that a toxicological synergism exists between DON and FA when fed to immature swine and that FA concentrations in feeds should be determined whenever DON analysis is conducted.

Aging↗

PubMed2005

[Mycological examination of domestic unpolished rice and mycotoxin production by isolated Penicillium islandicum].

Fungi growing on domestic rice were examined from April to June, 2003. One hundred samples of rice, which had been harvested in the autumn of 2002, were collected from the local market, and 15 samples of stored rice, which had been harvested in 2001 and stored in warehouses under government control, were used as samples. From each sample, 50 grains (100 grains in total) were plated on potato-dextrose agar (PDA) and malt yeast 40% sucrose agar (M40YA) containing chloramphenicol after being washed with sterile distilled water to remove any microorganisms on the surface, and incubated at 25 degrees C for a week. For most of the rice samples harvested in the preceding year, the proportion of grains infected with fungi was less than 20% of the total grains tested. In about half the samples of rice stored for one and half years, more than 80% of the grains were infected with fungi that grew on M40YA. The major genera of fungi isolated from the rice harvested in the preceding year were Penicillium and Alternaria, and those from the rice stored for one and a half years were Aspergillus, Penicillium and Eurotium. P. islandicum, A. versicolor, A. ochraceus and others were isolated as possible mycotoxin-producers in the mycoflora of domestic rice. P. islandicum was isolated from 3 samples, and 82% of the grains were infected with this fungus in one sample. All three isolates from these samples appeared to produce luteoskyrin on Czapek yeast extract agar, based on TLC and HPLC analysis.

Aspergillus↗

PubMed1982

Digestion of dry matter and amino acids and energy utilization by chicks fed molded corn containing mycotoxins.

A study was conducted to determine the ability of chicks to digest dry matter and amino acids and to utilize the energy from uncontaminated corn and contaminated corn containing mycotoxins. The contaminated corn contained either aflatoxin from natural molding, citrinin by artificially molding with a Penicillum spp., or ochratoxin by inoculation with Aspergillus ochraceus. Compared to uncontaminated corn, none of the criteria measured was affected in corn contaminated with aflatoxin. Dry matter digestibility, amino acid digestibility, and energy utilization were reduced (P less than .05) when corn was artificially molded with the Pencillium spp. and with A. ochraceus.

Aflatoxins↗

PubMed1987

Avian diuretic response to renal portal infusions of the mycotoxin citrinin.

Citrinin is a nephrotoxic mycotoxin produced by common molds. Previous research has shown that citrinin causes increased urine flow, increased free water clearance, and increased sodium, potassium, and inorganic phosphate excretion. The present study was conducted to evaluate the dose-response effects of citrinin and to further evaluate previously reported phosphaturic effects of citrinin. Ureteral urine was collected from anesthetized domestic fowl during a control period (30 min) and during unilateral renal portal infusion (90 min) of citrinin carrier vehicle, 200 ppm citrinin, or 400 ppm citrinin. Comparisons of the portal infused vs. uninfused kidneys were used to evaluate the direct effects of citrinin. Citrinin caused acute (unilateral) dose-related increases in urine flow, free water clearance, and fractional sodium excretion and dose-related decreases in urine osmolality. Citrinin had no direct effect on glomerular filtration rates, fractional potassium excretion, or fractional inorganic phosphate excretion. An additional group of birds received systemic intravenous infusions of parathyroid hormone (PTH) beginning 40 min after the start of unilateral renal portal infusion of citrinin. The citrinin and PTH infusion were continued for 60 min. Fractional inorganic phosphate excretion increased bilaterally during the citrinin-PTH infusion period but citrinin had no direct phosphaturic effect. Previously reported phosphaturic effects of citrinin were not confirmed in the present study.

Animals↗

PubMed1989

Influence of degree of acetylation of scirpenol mycotoxins on feed refusal by chickens.

The refusal by young chickens of feed containing graded levels (0, 1.25, 2.5, 5.0, 10.0, 20.0, and 40.0 micrograms/g of diet) of the Fusarium mycotoxins scirpentriol (STO), monoacetoxyscirpenol (MAS), diacetoxyscirpenol (DAS), and triacetoxyscirpenol (TAS) was tested in a defined experimental model. The order of activity as measured by minimum effective dose was DAS greater than MAS = STO greater than TAS whereas the order measured by percentage refusal at 10, 20, and 40 micrograms/g was MAS greater than DAS greater than STO greater than TAS. These results imply that feed refusal associated with corn and feed infested with Fusarium sps. might be a multiple toxicosis because the scirpenols, which are not tested for routinely, can occur together naturally.

Acetylation↗