• Mycobiology
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• v.35 no.2
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• pp.47-53
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• 2007

The prevalence and population density of the mycobiota of 50 samples belonging to 10 kinds of spices (anise, black pepper, red pepper, black cumin, peppermint, cardamom, clove, cumin, ginger and marjoram) which collected from different places in Jeddah Governorate were studied. The natural occurrence of mycotoxins in those samples was also investigated. Fifteen genera and thirty-one species of fungi in addition to one species variety were isolated and identified during this study. The most common genera were Aspergillus, Penicillium and Fusarium. Aflatoxins ($12{\sim}40\;{\mu}g/kg$) were detected in the extract of 5 samples of each of anise seeds and black pepper fruits; three samples of black cumin seeds and on sample only of each of peppermint and marjoram leaves out of 5 samples tested of each. Sterigmatocystin ($15{\sim}20\;{\mu}g/kg$) was detected in some samples of red pepper, cumin and marjoram. The inhibitory effects of 10 kinds of powdered spices were tested against 3 toxigenic isolates of fungi (Aspergillus flavus, A. versicolor and Penicillium citrinum). Clove proved to be antimycotic compounds. It inhibited the growth of the tested toxigenic fungi. Black pepper, peppermint, cardamom, cumin and marjoram completely inhibited aflatoxins production, while black pepper and cardamom also completely inhibited sterigmatocystin production.

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.5
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• pp.706-713
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• 2003

Two experiments were conducted to evaluate the efficacy of dietary FERMKIT, a commercial toxin binder consisting of probiotic-fermented natural product containing chitin, chitosan and chitosan oligosaccharides ($FERMKITO^{(R)}$, EASY-BIO SYSTEM, Inc., Korea), in binding aflatoxin (AF) and zearalenone (ZEN) and ameliorating their mycotoxicity in meat type ducks. FERMKIT was supplemented to AF contaminated diets (at 120 ppb) at either 0.3 or 0.6% in experiment 1 and to ZEN contaminated diets (at 150 ppb) at 0.6% in experiment 2. In experiment 1 body weight gains were reduced by 37% and mortality was increased by 18% in ducks fed diet contaminated with AF at 120 ppb compared to ducks fed control diet (<10 ppb AF) for the 4-wk experimental period. However, dietary FERMKIT supplementation effectively alleviated overall toxicity induced by AF. The significant treatment-related changes in feather growth, web-toe hemorrhage, leg deformity, liver paleness, organ weights, hematological values and serum biochemical values, as compared to the control, were observed. The FERMKIT supplementation significantly diminished the adverse effects of AF and restored all the parameters measured back (<0.05) toward the control values. These findings indicated that FERMKIT, when added at the levels of 0.3 or 0.6% in the 120 ppb AF diets, could modulate the toxicity of AF with percentage sorption capacity of 52.70% at the level 0.3% and 79.85% at the level 0.6% of the diets (experiment 1). In experiment 2, FERMKIT, when added at 0.6% to the 150 ppb ZEN diets for the 4-wk experimental period, diminished the toxicity as shown by body weight gain, weights of testicles, oviducts, Bursa of Fabricius and cloaca eversion score as compared with the controls (<10 ppb ZEN) and 150 ppb ZEN diet with no added FERMKIT. The findings indicated that FERMKIT could be protective against the effects of ZEN in young growing ducks with percentage sorption capacity of 67.11% as evaluated from toxicity index parameter measured when added at 0.6% of the diets containing 150 ppb ZEN.

• Journal of Preventive Medicine and Public Health
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• v.9 no.1
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• pp.77-86
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• 1976

This study was attempted to know that the interactions of various fungi, and methionine and $MgSO_4$ introduced as the substrate of culture media for fungi were affected to produce aflatoxins by Asp. flavus. 5 different fungi were isolated from the fermented soybean mash and were cultured in Chemically Defined medium (C. D. media) and soybean mash at $25^{\circ}C$ for 10 days. (1) It was confirmed that Asp. flavus produced aflatoxins in the C. D. medium and soybean mast, but that Asp. niger, Asp. oryzae, Asp. awamori and Asp. terreus did not produced them respectively. (2) Asp. flavus cultured with Asp. niger did not produce aflatoxins in C. D. medium, but produced in soybean mash, in other hand, Asp. flavus with other fungi except Asp. niger produced aflatoxins in C. D. medium and soybean mash. (3) The growth of fungi were more prosperous in the seperate culture than in the mixed culture. (4) In the C. D. medium added 20% of cultured medium of Asp. niger, Asp. flavus did not produce aflatoxins but other cultured medium did not prohibit the production of aflatoxins by Asp. flavus. (5) On the contrary, $MgSO_4$ increasing the productivity of aflatoxins by Asp. flavus in the C. D. medium, methionine known as one of precursor of aflatoxins did not affected the increasing productivity with significance.

• Journal of the Korean Society of International Agriculture
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• v.23 no.5
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• pp.513-519
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• 2011

In recent, the cultivation of maize in the world is being increased as a feed for the animal due to the increase of the large amount of meat consumption. However, reduction of supply for the feeding maize by the natural disaster such as drought, flooding, and demanding materials for bioenergy are attributed to increase the cereal price of the world that caused for the fluctuation of prices. The research has been done to provide useful information to the Korean agricultural investor regarding the current status of maize production and distribution in Cambodia. The maize cultivation of Cambodia in 2009 presented as a second major crop at the area of 6.8% in the total crop production area, and it continuously increased maize production yearly basis for the internal uses as well as for the exportation. The total amount of production showed by amount of 0.92 million tons due to the increased production of unit area. The yield production of unit area in current shows about 4 tones per hectare. About 90% of total production produced during August to September at wet season, and area of Batambang province produced about 70% of the total production. The production of feeding maize cultivated about 70% of the total cultivation area, and the exportation have done around 60% and remains were consumed as a domestic uses. The prospects of maize production in Cambodia will be increased due to the acceleration of livestock industry as 8.7% of annual growth rate.

• 한국균학회소식:학술대회논문집
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• 2015.11a
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• pp.28-28
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• 2015

Asexual reproduction or conidiation in aspergilli is a primary mean to produce their progenies that is environmentally and genetically controlled tightly. Previously, intensive researches in the model fungus Aspergillus nidulans disclosed some genes playing important roles in asexual and sexual development. Among them, one gene encoding a putative helix-loop-helix (HLH) transcription factor, named ndrA, has been isolated and characterized as a downstream regulator of developmental master regulator NsdD. By using comparative genome search of A. niduans NdrA protein, its orthologues have been identified in A. fumigatus and A. flavus, respectively (AfudrnA and AfldrnA). Deletion of the ndrA genes in both Aspergillus species made them unable to produce the conidia yet abundant production of sclerotia in A. flavus. Complementation of ndrA deletion strains by intact ndrA ORFs has restored the conidiation as in the control strains. In A. fumigatus, ndrA deletion also resulted in loss of conidiation phenotype. Northern analyses showed that the ndrA genes in both Aspergillus species are highly expressed at the early stage of the conidiation. Interestingly, the ndrA genes were found to be necessary for the proper expression of brlA genes. Antifungal sensitivity test revealed that the ndrA genes might be responsible for the sensitivity or resistance to some antifungal agents. However, ndrA deletion did not greatly influence the growth in both strains. And the A. flavus ndrA gene did not affect the aflatoxin production. Taken together, ndrA genes in Aspergillus species could be an important positive regulator of conidiation under the regulation of the nsdD gene yet upstream of the brlA gene.

• Mycobiology
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• v.49 no.2
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• pp.151-160
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• 2021

Despite recent studies, relatively few are known about the diversity of fungal communities in the deep Atlantic Ocean. In this study, we investigated the diversity of fungal communities in 15 different deep-sea sediments from the South Atlantic Ocean with a culture-dependent approach followed by phylogenetic analysis of ITS sequences. A total of 29 fungal strains were isolated from the 15 deep-sea sediments. These strains belong to four fungal genera, including Aspergillus, Cladosporium, Penicillium, and Alternaria. Penicillium, accounting for 44.8% of the total fungal isolates, was a dominant genus. The antiaflatoxigenic activity of these deep-sea fungal isolates was studied. Surprisingly, most of the strains showed moderate to strong antiaflatoxigenic activity. Four isolates, belonging to species of Penicillium polonicum, Penicillium chrysogenum, Aspergillus versicolor, and Cladosporium cladosporioides, could completely inhibit not only the mycelial growth of Aspergillus parasiticus mutant strain NFRI-95, but also the aflatoxin production. To our knowledge, this is the first report to investigate the antiaflatoxigenic activity of culturable deep-sea fungi. Our results provide new insights into the community composition of fungi in the deep South Atlantic Ocean. The high proportion of strains that displayed antiaflatoxigenic activity demonstrates that deep-sea fungi from the Atlantic Ocean are valuable resources for mining bioactive compounds.

• Journal of Life Science
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• v.21 no.1
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• pp.96-101
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• 2011

S-Adenosyl-L-methionine synthtase (SAM-s) catalyzes the biosynthesis of SAM from ATP and L-methionine. SAM plays important roles in the primary and secondary metabolism of cells. A metK encoding a SAM-s was searched from Streptomyces natalensis producing natamycin, a predominantly a strong antifungal agent, inhibiting the growth of both yeasts and molds and preventing the formation of aflatoxin in filamentous fungi. To obtain the metK of S. natalensis, PCR using primers designed from the two highly conserved regions for metK genes of Streptomyces strains was carried out, and an intact 1.2-kb metK gene of S. natalensis was cloned by genomic Southern hybridization with PCR product as a probe. To identify the function of the cloned metK gene, it was inserted into pSET152ET for its high expression in the Streptomyces strain, and then introduced into S. lividans TK24 as a host by transconjugation using E. coli ET12567(pUZ8002). The high expression of metK in S. lividans TK24 induced actinorhodin production on R5 solid medium, and its amount in R4 liquid medium was 10-fold higher than that by exconjugant including only pSET152ET.

• Journal of Life Science
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• v.17 no.6 s.86
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• pp.791-797
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• 2007

We studied the inhibitory effect of solvent fractions from doenjang on mutagenicity using Salmonella typhimurium TA100 in Ames test. We also investigated the effect of solvent fractions from doenjang on the growth of tumor cells and the production of interleukin-2 (IL-2). The treatment of dichlorormethane and ethylacetate fractions (2.5 mg/assay) from doenjang to Ames test system inhibited aflatoxin B$_1$ (AFB$_1$) induced mutagenicity by 96% and 97%, respectively, and showed a higher antimutagenic effect than other solvent fractions. In case of N-methyl-N'-nitro-N-nitrosoguamidine (MNNG) induced mutagenicity, the ethylacetate fraction showed the highest inhibitory effect (by 75%) among the other sol-vent fractions, although the inhibitory effect was not stronger compared to AFB$_1$ induced mutagenicity. The treatment of dichloromethane and ethylacetate fractions markedly inhibited the growth of Yac-1 (by 80% and 94%, respectively) and sacroma-180 cancer cells (by 60% and 96%, respectively) after 4 days of incubation at 37${\circ}$C. To elucidate the immunological mechanism of antitumor activity of doenjang, spleen cells of Balb/c mouse were exposed to the dichloromethane and ethyl-acetate fractions for 24 hours at 37${\circ}$C . The culture supernatants following the treatment of djchloromethane and ethylacetate factions to spleen cells increased the production of IL-2. These results indicated that the anticarcinogenic effect of doenjang was mediated by the production of IL-2.