• The Plant Pathology Journal
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• v.15 no.1
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• pp.53-56
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• 1999

Fifty-three isolates of Fusarium graminearum were obtained from corn and barley samples in several provinces of Korea. Gas chromatography-mass spectrometric analysis of trichothecenes produced by these isolates revealed that 37 and 16 isolates were nivalenol (NIV)- and deoxynivalenol (DON)-chemotypes, respectively. Two hundred and seventy-five nitrate-nonutilizing (nit) mutants were obtained from the isolates. Of these mutants, 187 were identified as nit1, nit3, or NitM, but 88 could not be identified as one of these classes. The highest frequency of nit mutant was nit1 (65%), followed by nit3 (20%) and NitM (15%). Higher frequency of NitM was observed in DON-chemotypes than in NIV-chemotypes. The mutants were used for vegetative compatibility group (VCG) analysis by examining heterokaryosis using complementary mutant pairs. No heterokaryon formation was observed among all 1,248 pairwise combinations, suggesting that all isolates tested belong to different VCGs. Higher frequency of self-incompatibility was observed in NIV-chemotypes than in DON-chemotypes. These results suggest that the like-lihood of asexual genetic recombination may be very low I F. graminearum under the field condition.

• Korean Journal of Medicinal Crop Science
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• v.12 no.2
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• pp.97-101
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• 2004

Volatile oil components were analysed in Perilla frutescens accessions collected from different regions in South Korea and identified chemotypes based on the major volatile oil components. Major components out of 30 compounds identified were limonene, perillaldehyde, perillaketone, isoegomaketone, beta-caryophyllene, beta-farnesene, myristicin, and dillapiole. P. frotescens collections were classified into four chemotypes : PA type (57.7% limonene and 19.8% perillaldehyde), PK type (89.8% perillaketone), ST type (82.4% sesquiterpene, as 54.5% beta-caryophyllene and 27.9% beta-farnesene) and PP type (40.3% phenylpropenes as 13.6% myristicin and 26.7% dillapiole) and 37.8% sesquiterpenes. The majorities of P. frutescens collections in this study belong to PA type (41.9%) and PK type(38.8%).

• The Plant Pathology Journal
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• v.35 no.6
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• pp.543-552
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• 2019

Fusarium asiaticum of the F. graminearum species complex causes head blight in small-grain cereals. The nivalenol (NIV) chemotypes of F. asiaticum is more common than the deoxynivalenol (DON) chemotypes of F. asiaticum or F. graminearum in Korea. To understand the prevalence of F. asiaticum-NIV in Korean cereals, we characterized the biological traits of 80 cereal isolates of F. asiaticum producing NIV or 3-acetyl-deoxynivalenol (3-ADON), and 54 F. graminearum with 3-ADON or 15-acetyl-deoxynivalenol (15-ADON). There was no significant difference in mycelial growth between the chemotypes, but F. asiaticum isolates grew approximately 30% faster than F. graminearum isolates on potato dextrose agar. Sexual and asexual reproduction capacities differed markedly between the two species. Both chemotypes of F. graminearum (3-ADON and 15-ADON) produced significantly higher numbers of perithecia and conidia than F. asiaticum-NIV. The highest level of mycotoxins (sum of trichothecenes and zearalenone) was produced by F. graminearum-3-ADON on rice medium, followed by F. graminearum-15-ADON, F. asiaticum-3-ADON, and F. asiaticum-NIV. Zearalenone levels were correlated with DON levels in some chemotypes, but not with NIV levels. Disease assessment on barley, maize, rice, and wheat revealed that both F. asiaticum and F. graminearum isolates were virulent toward all crops tested. However, there is a tendency that virulence levels of F. asiaticum-NIV isolates on rice were higher than those of F. graminearum isolates. Taken together, the phenotypic traits found among the Korean F. asiaticum-NIV isolates suggest an association with their host adaptation to certain environments in Korea.

• Korean Journal of Medicinal Crop Science
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• v.12 no.6
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• pp.459-462
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• 2004

Essential oil components were analysed in forty seven individual plants of Elsholtzia splendens collected from eight different regions in Korea to identify their chemotypes. Major oil components of chemotype 1 was dihydrotagentone (75%) and naginataketone and elsholtziaketone were not detected at all. Chemotype 2 was naginataketone (NK) type which content was more than 60%. Chemotype 3 had more than 60% of elsholtziaketone (EK) as major volatile oil. EK type and NK type plants selected were maintained stably in their progenies after seed generation. Naginatketone and elsholtziaketone had functional properties such as antioxidation and antibacteria.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 1999.04a
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• pp.34.1-34
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• 1999

• Journal of Marine Bioscience and Biotechnology
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• v.1 no.3
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• pp.137-143
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• 2006

The market for anti-inflammatory drugs is large and is expanding rapidly as populations age. Key to the development of new drugs are novel chemotypes. Marine organisms harbour a diverse range of unique compounds with applications in a multitude of disease indications. This review looks at anti-inflammatory compounds isolated from New Zealand marine organisms.

• Proceedings of the PSK Conference
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• 2003.10a
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• pp.58-59
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• 2003

There is considerable interest in the screening of higher plant extracts in modem drug discovery programs to discover new chemotypes with potent and selective biological activity. Such work may be performed in different laboratory settings, including those in academic institutions. In the case of cancer, plants offer the potential for the discovery of both cancer chemotherapeutic agents and cancer chemopreventives. (omitted)

• The Plant Pathology Journal
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• v.27 no.4
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• pp.354-359
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• 2011

Chemotype composition of Fusarium graminearum strains, isolated from durum wheat kernels from naturally FHB infected fields in Northern and Central Italy, was investigated by multiplex PCR. The different climatic and environmental conditions of the two examined areas separated by the Apennines affected the composition of chemotypes. 15Ac-DON chemotype was predominant in both the sub areas. Nivalneol chemotype was more frequent in the warmer sub area.

• Korean Journal Plant Pathology
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• v.14 no.5
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• pp.418-424
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• 1998

The production of 8-ketotrichothecenes, deoxynivalenol (DON), nivalenol (NIV), and their monoacetyl derivatives was studied in rice and corn cultures using 8 isolates of Fusarium graminearum which were obtained from corn and barley samples. Higher concentrations of trichothecenes were produced on rice than corn, and production of the toxins on rice was enhanced by growing the fungi at $25^{\circ}C$. The isolates were used for evaluation of toxin production and pathogenicity after artificial inoculation to 5 corn and 3 barley cultivars. The kinds and the relative amounts of trichothecenes produced in cultures were consistent with those in infected kernels of corn and barley with some exceptions. As for DON chemotypes, the ratios of 15-acetyl-DON to 3-acetyl-DON were varied among the pathogen-cultivar interactions. The corn and barley cultivars showed the significant differences of resistance to the Fusarium isolates in disease severity and seedling blight, and resistance ranking to the different isolates was varied. However, significant correlations were observed between the total concentrations of trichothecenes in infected kernels of corn and barley and pathogenicities of the Fusarium isolates to the hosts.

• Korean Journal of Microbiology
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• v.28 no.1
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• pp.83-89
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• 1990

Two strains of actinomycetes producing extracellular adenosine deaminase, strain J-845S and strain J-326TK, were isolated from soil. Strain J-845S was gram-positive and non-acid-fast. This strain formed whitish, rod-shaped, smooth and non-motile spores on the aerial mycelium, and the spore chain was spiral. The hyphae of the mycelium branched abundantly. Cell wall chemotypes of the strain were of type I containing LL-diaminopimelic acids, and of phospholipid type II, and then strain J-845S was designated as Streptomyces sp.. Strain J-326TK was gram-positive and non-acid-fast. The hyphae of primary and aerial mycelium fragmented into irregular rod of coccus-like elements. The aerial mycelium either did not branch or sparsely branched. Cell wall composition was of type I and phospholipid type I. Thus, strain J-326TK was identified as Nocardioides sp.