• Korean Journal of Poultry Science
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• v.21 no.2
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• pp.113-117
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• 1994

Of the 200, 000 known species of molds, only 50 or 60 are known to be harmful to humans or livestock. Certain fungi that grow on grains and grasses can produce chemical substances called mycotoxins that adversely affect performance in poultry. There are several methods of preserving feed ingredients. The list includes: drying, antioxidants, mold inhibitors, organic acids, phosphates, cooking or toasting, fat extraction, blending and fermenting. Mold inhibitors are manufactured to inhibit mold growth and prevent the production of toxic substances. They are fungistats and not fungicides, that is, they only stop the growth of molds. Practical and cost-effective methods to detoxify mycotoxin containing feedstuffs are in great demand. 0.5% hydrated sodium calcium aluminosilicate added to the diet protected chicks from the deleterious effects of aflatoxin-contaminated feed. The dietary addition of antioxidants and methionine also significantly diminished the negative effects on body weight in chicks toxicated with 3.0 ppm aflatoxin B1.

• Asian-Australasian Journal of Animal Sciences
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• v.23 no.9
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• pp.1250-1260
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• 2010

Mycotoxins are secondary metabolites produced by fungi. These toxins pose serious health concerns to animals as well as human beings. Biodegradation of these mycotoxins has been considered as one of the best strategies to decontaminate food and feedstuffs. Biodegradation employs the application of microbes or enzymes to contaminated food and feedstuffs. Ruminants are considered to be resistant to the adverse effects of mycotoxins presumably due to the biodegrading ability of rumen microbes compared to mono-gastric animals. Therefore, rumen microbial source or microbial enzyme could be a great asset in biological detoxification of mycotoxins. Isolation and characterization of pure culture of rumen microorganisms or isolation and cloning of genes encoding mycotoxin-degrading potential would prove to have overall beneficial impact in the food and feed industry.

• Journal of Microbiology and Biotechnology
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• v.10 no.2
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• pp.154-160
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• 2000

Aflatoxin B1 is known as the most potent mycotoxin produced by several fungi. It has been demonstrated to be not only carcinogenic but teratogenic and mutagenic as well in humans. To prevent or inactivate aflatoxins, several chemical of physical methods were tested for ammoniation, using insecticides as an wxample, but they were unsuitable for food products. On the contrary, biological control by antagonistic microorgani는 is and ideal method. In order to control aflatoxin B1 biologically, the antagonists #07, #63, #75, #74, and #61 were separated from various samples by using the antagonistic activity test. Among them, culture filtrate part A (non heat-treated) of #63 and #74 on aflatoxin B1 produced by Aspergillus fkavus were shown to be 95% and 75%, respectively. Based on the morphological characteristics, #63 was deduced as an Azospirillum sp.

• Journal of Mushroom
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• v.19 no.2
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• pp.81-87
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• 2021

Roridin E, produced by Podostroma cornu-damae, is a mycotoxin with anticancer activity. To increase the content of roridin E, submerged culture conditions were optimized using response surface methodology. Three factors, namely, medium initial pH, incubation time and agitation speed were optimized using a Box-Behnken design. The optimum submerged culture conditions to increase the content of roridin E included a medium with an initial pH of 4.0, an incubation time of 12.90 days, and an agitation speed of 63.03 rpm. The roridin E content in the submerged culture, under the aforementioned conditions, was 40.26 mg/L. The findings of this study can help lower the current price of roridin E and promote its related research.

• Journal of Environmental Health Sciences
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• v.42 no.6
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• pp.465-477
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• 2016

Objectives: This review examined the scientific evidence regarding the impact of climate change on food safety. Methods: The impact of climate change on food safety was assessed based on a survey of related publications reported in the past 20 years. The terms used for literature selection reflect three aspects: climate change; food; and food safety. Results: Climate change is expected to affect the key elements of food production - water and climate. These impact on food safety through many different pathways. Directly, food shortages according to the population grovoth result in a food security/food supply problem, These relationships are commonly understood. The indirect impacts include an increase in food-borne diseases and pathogens, increased mycotoxin production, and increased risk of pesticide residues in foods due to greater use of pesticides in response to warming and increased precipitation and the accompanying diseases in certain crops. Field studies and statistical and scenario analyses were performed to provide evidence. However, quantification of these relationships is still lacking. Conclusion: Adaptation measures at the local and community levels are essential since the pressures from weather and climate events may differ according to region and sector. It is recommended that we go beyond empirical observations of the association between climate change and food safety and develop more scientific explanations. We also need to explore alternative materials for bioenergy demands in order to improve sustainability.

• The Plant Pathology Journal
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• v.27 no.4
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• pp.301-309
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• 2011

The filamentous fungus Fusarium graminearum is an important cereal pathogen. Although quantitative realtime PCR (qRT-PCR) is commonly used to analyze the expression of important fungal genes, no detailed validation of reference genes for the normalization of qRT-PCR data has been performed in this fungus. Here, we evaluated 15 candidate genes as references, including those previously described as housekeeping genes and those selected from the whole transcriptome sequencing data. By a combination of three statistical algorithms (BestKeeper, geNorm, and NormFinder), the variation in the expression of these genes was assessed under different culture conditions that favored mycelial growth, sexual development, and trichothecene mycotoxin production. When favoring mycelial growth, GzFLO and GzUBH expression were most stable in complete medium. Both EF1A and GzRPS16 expression were relatively stable under all conditions on carrot agar, including mycelial growth and the subsequent perithecial induction stage. These two genes were also most stable during trichothecene production. For the combined data set, GzUBH and EF1A were selected as the most stable. Thus, these genes are suitable reference genes for accurate normalization of qRT-PCR data for gene expression analyses of F. graminearum and other related fungi.

• Journal of Food Hygiene and Safety
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• v.23 no.1
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• pp.73-79
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• 2008

The productions of beauvericin and enniatins H, I, and MK1688 by Fusarium oxysporum KFCC 11363P were investigated on rice substrate at four temperatures (15, 20, 25, and $30^{\circ}C$) and three moisture contents (10, 20, and 40%). The largest amount of beauvericin ($718.0\;{\mu}g/g$) was produced at $25^{\circ}C$, and maximum levels of enniatin H ($781.9\;{\mu}g/g$), I ($725.8\;{\mu}g/g$), and MK1688 ($425.8\;{\mu}g/g$) were measured by high pressure liquid chromatography (HPLC) at the same temperature. The optimal moisture content for the production of beauvericin and enniatins H, I, and MK1688 was 40%, and the trace amounts of these toxins were observed at 10% moisture content. Sixty five grain samples (n=65) were tested for the monitoring of beauvericin. This mycotoxin was detected in six grain samples including three maize, two barley, and one wheat samples. The highest contamination level of beauvericin was observed in maize sample ($0.23\;{\mu}g/g$).

• The Korean Journal of Mycology
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• v.49 no.3
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• pp.303-313
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• 2021

Peanuts in storage were estimated for mycotoxigenic fungi and mycotoxins. Peanut samples collected from storages in Gochang were mainly contaminated with Fusarium (17.2±28.0%), Penicillium (12.4±28.0%), and Aspergillus (8.0±7.6%). Other genera, including Talaromyces, Rhizopus, Rhizoctonia, Trichocladium, Clonostachys, Mucor, Chaetomium, Trametes, Epicoccum, and Humicola, were also found. Although aflatoxins were not detected in the peanut samples, 29 strains of Aspergillus flavus were identified using molecular marker genes. Among them, 17 selected isolates produced aflatoxins in solid culture media ranging from 0.61-187.82 ㎍/kg. All of them could produce both aflatoxin B₁ and B₂ and some (n=5) produced additional G₁, G₂, or both. This study is the first report that A. flavus stains obtained from Korean stored peanut are aflatoxigenic.

• 한국균학회소식:학술대회논문집
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• 2018.05a
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• pp.41-41
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• 2018

There has been an impetus in the development of biocontrol agents (BCAs) with the removal of a number of chemical compounds in the market, especially in the European Union. This has been a major driver in the development of Integrated Pest Management systems (IPM) for both pest and disease control. For control of mycotoxigenic fungi, there is interest in both control of colonization and more importantly toxin contamination of staple food commodities. Thus the relative inoculum potential of biocontrol agent vs the toxigenic specie sis important. The major bottlenecks in the production and development of formulations of biocontrol agents are the resilience of the strains, inoculum quality and formulation with effective field efficacy. It was recently been shown for mycotoxigenic fungi such as Aspergillus flavus, under extreme climate change conditions, growth is not affected although there may be a stimulation of aflatoxin production. Thus, the development of resilient biocontrol strains which can may have conserved control efficacy but have the necessary resilience becomes critical form a food security point of view. Indeed, under predicted climate change scenarios the diversity of pests and fungal diseases are expected to have profound impacts on food security. Thus, when examining the identification of potential biocontrol strains, production and formulation it is critical that the resilience to CC environmental factors are included and quantified. The problems in relation to the physiological competence and the relative humidity range over which efficacy can occur, especially pre-harvest may be increase under climate change conditions. We have examined the efficacy of atoxigenic strains of A. flavus and Clanostachys rosea and other candidates for control of A. flavus and aflatoxin contamination of maize, and for Fusarium verticillioides and fumonisin toxin control. We have also examined the potential use of fluidized-bed drying, nanoparticles/nanospheres and encapsulation approaches to enhance the potential for the production of resilient biocontrol formulations. The objective being the delivery of biocontrol efficacy under extreme interacting climatic conditions. The potential impact of climate change factors on the efficacy of biocontrol of fungal diseases and mycotoxins are discussed.

• Advances in Traditional Medicine
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• v.5 no.4
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• pp.308-315
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• 2005

Aflatoxin contamination is a major problem in several food crops. Aflatoxin, a mycotoxin, produced by Aspergillus flavus has gained immense concern in the scientific world because of its tremendous harmful effects. The study was focused to see the effect of oil and aqueous extract of neem (Azadirachta indica) seeds on the growth of Aspergillus and production of aflatoxin by the mold. Various amounts of neem oil $(5\;-\;50\;{\mu}l/ml)$ and aqueous extract of neem (5 - 50 mg/ml) were used both in the broth as well as the solid medium. Fungistatic (MIC) and minimal fungicidal concentrations (MFC) were found to be $10\;{\mu}l/ml$ and $50\;{\mu}l/ml$ respectively for neem seed oil. At the concentration of $5\;{\mu}l/ml$ neem oil and 5 mg/ml of aqueous extract, a significant decrease in the aflatoxin content was found in broth medium. Aflatoxin production was totally inhibited at $50\;{\mu}l/ml$ and 50 mg/ml for neem oil and aqueous extract of neem respectively, in both treatments. There was significant inhibition of mycelium dry weight by the neem seed oil. Mycelial growth was totally inhibited at $20\;{\mu}l/ml$ of neem seed oil concentration in broth, whereas it was not affected at all by aqueous extract. It can therefore be inferred that the oil and extract from the neem seed leads to inhibition of aflatoxin production while neem seed oil also significantly inhibits the mycelial growth. Neem seed oil thus can be used as potent, natural and easily available anti-aflatoxigenic agent.