• Korean Journal of Microbiology
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• v.18 no.2
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• pp.73-90
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• 1980

Ninerty one of Trichoderma spp. were isolated from ginseng growing bed, dead trees and muchroom in Korea from March 1978 to June 1979. Six species were identified as T. hamatum(13 strains), T, roningii(17 strains), T. aureoviride(4 strains), but other six strains(strain No. 111, 125, 127, 130, and 503) unidentified by Rifai's key. The reason which is not identified is as following. According to Rifai's key, phialid, phialospore and colony's colour of four strains (strain No. 125, 126, 127 and 130) are like T. longibrachiatum, but they are different from Rifai's method, because sterile-hypha often appears. the fature of standard strain ATCC no. 13631 T. longibrachiatum is like ster9ile-hypha that is used strains in this experiment. The morphology of strain No.503 is the same as T. hamatum except phialospore. Gnerally, T. hamatum's phialospore is subcylindrical, but strain No. 503 is regular ovoid. Therefore, strain No.503 cannot be identified by Rifai's key. The property, strain No.111's phialid is very irregular $(5{\sim}20{\times}2{\sim}2.5{\mu})$) and its phialospore $(4.0{\sim}6.0{\times}3.0{\sim}4.0{\mu})$) is subcylindrical, is uncomfortable to Rifai's method. The standard strains used in this experiment are 7 kinds of Trichoderma spp. received from ATCC.

• ALGAE
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• v.23 no.2
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• pp.115-118
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• 2008

Cells of the dinoflagellate Peridinium were frequently observed in water samples of Togyo reservoir, and some species were responsible for dense blooms. Recently, we could identify them as P. bipes f. occultatum Lindem. and P. aciculiferum Lemm., considering morphology (Ki et al. 2005a; Ki and Han 2005b): However, some unidentified Peridinium cells with different shapes and body sizes were found among the samples collected during early spring. Here we describe their morphological characteristics such as thecal plate and body size to characterize its taxonomic identity by morphological characters. The formula of epithecal plates was recorded as 4 apical, 2 intercalary and 7 precingular plates (i.e. 4’', 2a, 7’'’') and the epicone in an apical view was symmetric. An apical pore was easy to make out under a light microscope. No cingular displacement was observed. The average body size was 33 $\mu$m in length with a range of 26-36 $\mu$m, and average 26 $\mu$m in width with a range of 21-31 $\mu$m, respectively; the cell was, therefore, shown slightly elongated. This way we identified Peridinium umbonatum Stein, 1883 for the first time from Korean freshwaters.

• The Plant Pathology Journal
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• v.23 no.4
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• pp.287-294
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• 2007

Endophytic fungi were isolated from surface sterilized root tissues of Aralia elata and Aralia continentalis, collected from farmer's field in Chungnam province, Republic of Korea, in 2005. Based on ITS sequence analysis, 24 fungal genera were characterized from 359 isolates, belonging to 22 Ascomycota, 1 Glomeromycota and 1 Oomycota. Strumella, Rhizopycnis and Entrophospora in A. elata and Rhizopycnis and Leptosphaeria in A. continentalis were the most abundant taxa. Out of 24 genera, Entrophospora, Leptodontidium, Neoplaconema, Paraconiothyrium, Rhizopycnis, Strumella and Tumularia were new to Korea. A total of 110 isolates were tested for antifungal activities against six plant pathogenic fungi. Out of these, 39 isolates showed antifungal activity against at least one plant pathogenic fungi. Four isolates of Pyrenochaeta, 1 isolate of Entrophospora and 1 unidentified fungus strongly inhibited the growth of six plant pathogenic fungi.

• Nuclear Engineering and Technology
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• v.49 no.4
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• pp.668-674
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• 2017

Experimental verification of boron species in fuel CRUD (Chalk River Unidentified Deposit) would provide essential and important information about the root cause of CRUD-induced power shifts (CIPS). To date, only bonaccordite and elemental boron were reported to exist in fuel CRUD in CIPS-troubled pressurized water reactor (PWR) cores and lithium tetraborate to exist in simulated PWR fuel CRUD from some autoclave tests. We have reevaluated previous analysis of similar threadlike crystals along with examining some similar threadlike crystals from CRUD samples collected from a PWR cycle that had no indications of CIPS. These threadlike crystals have a typical [Ni]/[Fe] atomic ratio of ~2 and similar crystal morphology as the one (bonaccordite) reported previously. In addition to electron diffraction study, we have applied electron energy loss spectroscopy to determine boron content in such a crystal and found a good agreement with that of bonaccordite. Surprisingly, such crystals seem to appear also on corroded surfaces of Alloy 600 that was exposed to simulated PWR primary water with a dissolved hydrogen level of $5mL\;H_2/kg\;H_2O$, but absent when exposed under $75mL\;H_2/kg\;H_2O$ condition. It remains to be verified as to what extent and in which chemical environment this phase would be formed in PWR primary systems.

• The Korean Journal of Mycology
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• v.26 no.1 s.84
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• pp.97-102
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• 1998

VA-mycorrhizal spores were collected from the 14 citurs orchards of different soil textures and locations in Cheju island. Five species and two kinds of spores were identified as based on the morphological characteristics of the spores; Acaulospora bireticulata, Glomus deserticola, G. geosporum, G. vesiculiferum, and Sclerocystis pachycaulis. Additionally, two kind spores of Acaulospora were also observed but difficult to be identified in this moment. Glomus deserticola and unidentified spores of Acaulospora (brown spores sized 90 to $125\;{\mu}m$ in diameter) were most frequently observed in the all soil specimens in Cheju, while the other kinds of spores were rarely observed in the soil of Cheju.

• Journal of Ecology and Environment
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• v.29 no.4
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• pp.381-387
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• 2006

We analyzed the total yields and composition of essential oils in leaf extracts of Nepeta cataria by Gas Chromatography Mass Spectrometry (GC-MS). Thirty-six compounds representing 97.0% of total oil were detected. The major constituents of essential oils in Nepeta cataria were nepetalactone (90.9%), unidentified compound (Retention time 17.35; 1.82%), 1,8-cineol (1.49%), ${\beta}-caryophyllene$ (1.12%), and ${\beta}-pinene$ (1.078%). The volatile compounds in leaf extracts of N. cataria concentrated to nepetalactone ($88.83{\sim}93.33%$) remarkably. In the essential oil of N. cataria cis,trans-nepetalactone ($30.2{\sim}37.8%$) and cis,cis-nepetalactone ($31.5{\sim}37.0%$) were found as the main constituents. The effects of essential oil of N. cataria on the growth of six microorganisms (Bacillus cereus, B. subtilis, B. amyloliquefaciens, Escherichia coli, Staphylococcus aureus subsp. aureus, and Pseudomonas aeruginosa) were investigated. The essential oil of N. cataria had strong inhibitory effect on the growth of three fungal species (Bacillus cereus, B. subtilis, and B. amyloliquefaciens). The essential oil from N. cataria was found to have a low antimicrobial activity against Staphylococcus aureus subsp. aureus, while no activity were found against Escherichia coli and Pseudomonas aeruginosa. Results indicate the significant antimicrobial effect, which may be depended on the yield of nepetalactone.

• The Korean Journal of Physiology and Pharmacology
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• v.25 no.3
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• pp.251-258
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• 2021

Flos magnoliae (FM), the dry flower buds of Magnolia officinalis or its related species, is a traditional herbal medicine commonly used in Asia for symptomatic relief of and treating allergic rhinitis, headache, and sinusitis. Although several studies have reported the effects of FM on store-operated calcium entry (SOCE) via the ORAI1 channel, which is essential during intracellular calcium signaling cascade generation for T cell activation and mast cell degranulation, the effects of its isolated constituents on SOCE remain unidentified. Therefore, we investigated which of the five major constituents of 30% ethanoic FM (vanillic acid, tiliroside, eudesmin, magnolin, and fargesin) inhibit SOCE and their physiological effects on immune cells. The conventional whole-cell patch clamp results showed that fargesin, magnolin, and eudesmin significantly inhibited SOCE and thus human primary CD4+ T lymphocyte proliferation, as well as allergen-induced histamine release in mast cells. Among them, fargesin demonstrated the most potent inhibitory effects not only on ORAI1 (IC50 = 12.46 ± 1.300 μM) but also on T-cell proliferation (by 87.74% ± 1.835%) and mast cell degranulation (by 20.11% ± 5.366%) at 100 μM. Our findings suggest that fargesin can be a promising candidate for the development of therapeutic drugs to treat allergic diseases.

• The Plant Pathology Journal
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• v.35 no.4
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• pp.362-371
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• 2019

Plant phenotype is affected by a community of associated microorganisms which requires dissection of the functional fraction. In this study, we aimed to culture the functionally active fraction of an upland soil microbiome, which can suppress tomato bacterial wilt. The microbiome fraction (MF) from the rhizosphere of Hawaii 7996 treated with an upland soil or forest soil MF was successively cultured in a designed modified M9 (MM9) medium partially mimicking the nutrient composition of tomato root exudates. Bacterial cells were harvested to amplify V3 and V4 regions of 16S rRNA gene for QIIME based sequence analysis and were also treated to Hawaii 7996 prior to Ralstonia solanacearum inoculation. The disease progress indicated that the upland MM9 $1^{st}$ transfer suppressed the bacterial wilt. Community analysis revealed that species richness was declined by successive cultivation of the MF. The upland MM9 $1^{st}$ transfer harbored population of phylum Proteobacteria (98.12%), Bacteriodetes (0.69%), Firmicutes (0.51%), Actinobacteria (0.08%), unidentified (0.54%), Cyanobacteria (0.01%), FBP (0.001%), OD1 (0.001%), Acidobacteria (0.005%). The family Enterobacteriaceae of Proteobacteria was the dominant member (86.76%) of the total population of which genus Enterobacter composed 86.76% making it a potential candidate to suppress bacterial wilt. The results suggest that this mixed culture approach is feasible to harvest microorganisms which may function as biocontrol agents.

• Fisheries and Aquatic Sciences
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• v.26 no.3
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• pp.169-180
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• 2023

Oreochromis niloticus is the most ecologically and economically important fish in tropical and sub-tropical aquatic systems. Recently, due to sever anthropogenic stressors, hydrological variations and infestations of invasive alien species in Ethiopian water bodies, fish community structure and ecosystem of Lake Tana is changing alarmingly. So far, there is paucity of information on the morphometric relations and diet composition of O. niloticus in Lake Tana, gulf of Gorgora. A total of 309 fish samples were collected and their total length (TL), standard length (SL) and total weight (TW) were measured to determine morphometric relations; and gut contents were examined to identify most important food item in the diet of the fish. Results indicated that, the relation between TL and SL was significant (p < 0.001) and linear (SL = 0.942TL-2.41) while the relation between TL and TW was curvilinear (TW = 0.014 TL^2.8) indicating allometric growth. Among the total guts scrutinized, 53 (17.3%) of them were empty and the remaining 256 (82.7%) were non-empty. Phytoplankton constituted the largest bulk and occurred in 77% of the guts examined and volumetrically accounted 44.3%. Detritus and zooplankton had an intermediate importance by occurring 60.2% and 63.3% of all guts scrutinized and constituted about 25.6% and 15.5% of the total volume respectively. Contributions of macrophytes, insects, nematodes and unidentified food items were relatively low in their importance. Ontogenetic dietary shift was observed in the diet indicating an omnivorous feeding habit of the adult fish.

• Korean Journal of Ecology and Environment
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• v.39 no.3 s.117
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• pp.402-412
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• 2006

The Shihwa constructed wetland was established to treat the severely polluted water from Banwoul, Donghwa and Samhwa streams. This study was focused on investigating the dynamics of epiphytic algal communities on reed (Phragmites communis) planting area at 5 stations from October 2001 to June 2002. The concentration of total nitrogen and phosphorus of inlet stations from the streams were decreased after flowing through the wetland. However, the TN : TP ratios at all stations were slightly over 16 indicating that the total phosphorus may play some role as a limitation factor. Epiphytic algae on the reed were total 329 taxa which were composed of 295 species, 13 varieties, 3 forma and 18 unidentified species. The species numbers were recorded in the order of Chlorophyceae-Bacillariophyceae-Cyanophyceae-Euglenophyceae-Chrysophyceae. The relative percentage showed a seasonal variation from Cyanophyceae to Bacillariophyceae and to Chlorophyceae. The biomass of epiphytic algae measured by chlorophyll-a concentration ranged from 0.6 to $36.4\;{\mu}g\;cm^{-2}$. Dominant species were 16 taxa which were Lyngbya angusta of Cyanophyceae in the early investigation, and were changed to Stigeoclonium lubricum of Chlorophyceae, and Nitzschia palea of Bacillariophyceae etc. in the late. Species number, standing crops and chlorophyll-a concentrations of epiphytic algae showed higher values at the inlet stations than the stations after flowing through the wetland.