• Journal of Microbiology and Biotechnology
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• v.22 no.12
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• pp.1740-1748
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• 2012

A home-made meju sample contaminated naturally with aflatoxins was used for isolation of fungal strains. Overall, 230 fungal isolates were obtained on dichloran rosebengal chloramphenicol (DRBC) and dichloran 18% glycerol (DG18) agar plates. Morphological characteristics and molecular analysis of a partial ${\beta}$-tubulin gene and the internal transcribed spacer (ITS) of rDNA were used for the identification of the isolates. The fungal isolates were divided into 7 genera: Aspergillus, Eurotium, Penicillium, Eupenicillium, Mucor, Lichtheimia, and Curvularia. Three strains from 56 isolates of the A. oryzae/flavus group were found to be aflatoxigenic A. flavus, by the presence of the aflatoxin biosynthesis genes and confirmatory aflatoxin production by high-performance liquid chromatography (HPLC). The predominant isolate from DRBC plates was A. oryzae (42 strains, 36.2%), whereas that from DG18 was A. candidus (61 strains, 53.5%). Out of the 230 isolates, the most common species was A. candidus (34.3%) followed by A. oryzae (22.2%), Mucor circinelloides (13.0%), P. polonicum (10.0%), A. tubingensis (4.8%), and L. ramosa (3.5%). A. flavus and E. chevalieri presented occurrence levels of 2.2%, respectively. The remaining isolates of A. unguis, P. oxalicum, Eupenicillium cinnamopurpureum, A. acidus, E. rubrum, P. chrysogenum, M. racemosus, and C. inaequalis had lower occurrence levels of < 2.0%.

• The Korean Journal of Mycology
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• v.21 no.4
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• pp.247-272
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• 1993

Forty-eight fungal isolates were collected from the Korean traditional maejus and twenty-eight isolates of them were identified to be a hyphomycetous fungus(three genera and 20 species) Aspergillus flavus, A. flavus var columnaris, A. oryzae, A, oryzae var effusus, A. terreus, Scopula­riosis brevicaulis, Penicillium botryosum, P. gorlenkoanum, P. griseo-purpureum, P. citrinum, P. miczynskii, P. gaditanum, P. turolense, P. funiculosum, P. rubicundum, P. godlewskii, P. jensenii, P. roqueforti, P. volguense, P. verrucosum. Various 14 species of Penicillium were isolated from maejus, but all of them were not considered to be involved in the maeju fermentation. Otherwise, S. brevicaulis was especially collected from the maejus of various located areas, but were also related to the good quality of maejus under labratory conditions. A. flavus, A. oryzae P. tulolense, and P. funiculosum were also observed to be involved in the process of maeju.

• Korean journal of applied entomology
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• v.42 no.4
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• pp.329-334
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• 2003

To study the interaction between rice weevil and storage molds, the preference of rice weevil to the four mold species (Aspergilus candidus, A. niger, A. flavus and Penicillium spp.) and the resulting reproduction of the rice weevil were observed. The rice weevil preferred rice grains contaminated with the molds to autoclaved ones regardless of the mold species tested. Among the four mold species, A. candidus and Penicillium sp. were highly preferred than the others. Reproduction of the rice weevil was higher on the grains contalminated with A. candidus and Penicillium sp., than on autoclaved ones, but was lower on the grains contaminated with A. flavus. The partial disagreement between preference and reproduction of the rice weevil might be a suggestion that both the weevil behavior adapting nutritional requirements and the process of the long intensive coadaptation of the rice weevil and storage molds requiring similar moisture niche are the major components of the population interaction between the weevil and molds.

• Korean Journal of Microbiology
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• v.19 no.3
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• pp.142-152
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• 1981

One hundred and thirteen healed pulmonary tuberculosis patients and 11 patients with other underlying diseases were studied for evidence of pulmonary fungal infection because of persisting hemoptysis or chronic cough. Rediological, mycological and serological investigations revealed that 54 out of 124 patients were evidently infected with one or more species of fungi. A. fumigatus was isolated from 4 out of 70 patients whose sera did not react with antigens from this fungus, while it was isolated from 43 out of 47 serological reactors to this fungus. Chest radiography showed a distinct fungus ball in a cyst of one patient and in a preformed cavity in the lung of 17 healed tuberculosis patients and two other patients. The latter two patients were infected with A.flavus. Two patients, who were under the long period of immunosuppressive therapy, apparently succumbed to invasive aspergillosia due to A.fumigatus. A single or dual infection with A. flavus, A. nidulans, A.nidulans var. latus, C. albicans, and P. boydii were noticed in some patients without mycetomal shadow on chest radiographs. Young mycelial extract (ME) of A.fumigatus detected antibody in 95.8 percent of the sera from patients infected with this fungus, while it was isolated from 43 out of 47 serological reactors to this fungus. Chest radiography showed a distinct fungus ball in a cyst of one patient and in a performed cavity in the lung of 17 healed tuberculosis patients and two other patients. The latter two patients were infected with A. flavus. Two patients, who were under the long period of immunosuppressive therapy, apparently succumbed to invasive aspergillosis due to A.fumigatus. A single or dual infection with A. flavus, A. nidulans, A. niduans var. latus, C. albicans, and P. boydii were noticed in some patients without mycetomal shadow on chest radiographs. Young mycelial extract (ME) of A.fumigatus detected antibody in 95.8 percent of the sera from patients infected with this fungus, while the commercial culture filtrate antigen (GL) yielded 78.7 per cent positive result. Culture filtrate antigen, however, was comparable with ME. There was no single antigen with which all the serum specimens reacted. Fractionation of ME resulted in a loss of some activity although it excluded substances that reacted with C-reactive protein in a loss of some activity although it excluded substances that reacted with C-reactive protein. Most reactive and specific precipitinogens distributed in the fraction (FB) which was precipitable at 75 percent saturation with ammonium sulfate and eluted in a second peak in order from gel-filtration and which contained mostly proteinic components. Glycoproteins or polysaccharides rich fractions (FA and ASI) were relatively less effective in detecting antibody. Demonstration of antibody in the serum from patients using a battery of fungal antigens and of etiologically related fungi from clinical specimens are very useful laboratory procedures for the diagnosis of pulmonary fungal infection which is a common complication of tuberculosis.

• Journal of Microbiology and Biotechnology
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• v.24 no.8
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• pp.1081-1087
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• 2014

Aspergillus oryzae is generally recognized as safe, but it is closely related to A. flavus in morphology and genetic characteristics. In this study, we tested the aflatoxigenicity and genetic analysis of nine commercial A. oryzae strains that were used in Korean soybean fermented products. Cultural and HPLC analyses showed that none of the commercial strains produced detectable amount of aflatoxins. According to the molecular analysis of 17 genes in the aflatoxin (AF) biosynthetic pathway, the commercial strains could be classified into three groups. The group I strains contained all the 17 AF biosynthetic genes tested in this study; the group II strains deleted nine AF biosynthetic genes and possessed eight genes, including aflG, aflI, aflK, aflL, aflM, aflO, aflP, and aflQ; the group III strains only had six AF biosynthetic genes, including aflG, aflI, aflK, aflO, aflP, and aflQ. With the reverse transcription polymerase chain reaction, the group I A. oryzae strains showed no expression of aflG, aflQ and/or aflM genes, which resulted in the lack of AF-producing ability. Group II and group III strains could not produce AF owing to the deletion of more than half of the AF biosynthetic genes. In addition, the sequence data of polyketide synthase A (pksA) of group I strains of A. oryzae showed that there were three point mutations (two silent mutations and one missense mutation) compared with aflatoxigenic A. flavus used as the positive control in this study.

• BMB Reports
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• v.32 no.3
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• pp.317-319
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• 1999

A leucine aminopeptidase has been isolated from the culture medium of the soil fungus, Aspergillus flavus. The enzyme was found to be a glycoprotein, as judged by electrophoresis analysis and the subsequent staining by the periodic acid-Schiff's reagent. Carbohydrate moieties could be cleaved by N-glycosidase, but not by O-glycosidase, indicating that the glucans are linked to the asparagine residue in the protein. Removal of N-glucans was observed without prior denaturation of the protein, implying that the N-glycosidic linkage is exposed and accessible to glycosidase. When the activity of native or deglycosylated enzyme was measured in the presence of various metal ions, removal of carbohydrates increased the aminopeptidase activity of the enzyme.

• The Korean Journal of Malacology
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• v.26 no.1
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• pp.45-49
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• 2010

Up until now, we have identified 17 exotic species of Mollusca in Korea. These include Achatina (Lissachatina) fulica, Limax flavus, Limax marginatus, Deroceras reticulatum, Hawaiia minuscula, Zonitoides yessoensis, Zonitoides arboreus, Physa acuta, Pomacea canaliculata, Pomacea insularus, Crepidula (Crepidula) onyx, Mytilus galloprovincialis, Xenotrobus securis, Perna viridis, Argopecten irradians irradians, Pinctada fucata, and Pinctada margaritifera. Among them Achatina (Lissachatina) fulica, Pomacea canaliculata, Pomacea insularus, Argopecten irradians irradians, Pinctada fucata, and Pinctada margaritifera were intentionally introduced, whereas remainings were unintentionally introduced into Korean fauna. These foreign species can be divided into three groups on the basis of their habitats: A. fulica, L. flavus, L. marginatus, D. reticulatum, H. minuscula, Z. yessoensis, and Z. arboreus in terrestrial habitat; P. acuta, P. canaliculata, and P. insularus in fresh water; and C. onyx, M. galloprovincialis, L. fortuneikikuchii, P. viridis, A. irradiansirradians, P. fucata, and P. margaritifera in sea water. Taxanomically, 11 species belong to Gastropoda, whereas 6 species are classified to Bivalvia.

• Journal of Practical Agriculture & Fisheries Research
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• v.14 no.1
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• pp.85-92
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• 2012

To elucidate the mycotoxin production of Penicillium, Aspergillus and Fusarium spp. isolated from round bale silage, TLC analysis of culture filtrates were conducted. Mycotoxin citrin and patulin were detected from culture filtrates of Penicillium paneum. Aflatoxin was detected from culture filtrates of Aspergillus flavus. Gliotoxin are known to produce by A. fumigatus was not detected. Mycotoxins produces by Fusarium spp., Fumonisin, zearalenone and deoxynivalenol was not detected in the culture filtrates of Fusarium proliferatum.

• 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.

• The Plant Pathology Journal
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• v.18 no.4
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• pp.204-209
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• 2002

Andhra Pradesh is one of the major groundnut growing states in India. A total of 182 groundnut samples collected at harvesting from farmers fields in five districts, namely; Anantapur, Chittoor, Cuddapah, Kurnool, and Mahaboobnagar, during 1999 and 2000 rainy seasons were evaluated for the presence of mycotoxins (both aflatoxins and zearalenone) and toxigenic fungi. In samples collected from each district, average seed infection by Aspergillus flavus and Fusarium spp. was 11.9-18.3% and 5.6-12.8% in 1999, and 9.5-14.1% and 9.4-11.9% in 2000, respectively. Among the samples collected, 20.3% and 16.5% were contaminated with aflatoxin in 1999 and 2000, respectively, and in 11.4% and 8.7% of the seed samples collected in two seasons, the aflatoxin content was >30 $\mu\textrm{g}$/kg. An alarming aflatoxin content of 851.9$\mu\textrm{g}$/kg was found in samples collected from Anantapur district during the rainy season in 1999. Zearalenone was not detected in any of the samples collected in 1999, while 2 out of 103 samples collected in 2000 were contaminated with 35.1 and 129.4$\mu\textrm{g}$/kg. Under in vitro cultural conditions, 35.8% of the 173 A. flavus isolates collected from the groundnut samples produced aflatoxins at concentrations of 94.3-1598.6 ng/$\textrm{m}{\ell}$ and 3% of the 266 Fusarium spp. isolates produced 98.1-847.3 $\mu\textrm{g}$/g of zearalenone. The results emphasize the need for a more systematic and regular monitoring of pre-harvest aflatoxin contamination.