• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.30 no.4
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• pp.85-91
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• 1998

Habitative microorganisms were isolated from the floated air and surface of record materials of library with ancient archives. The major ecological fungi from them were isolated and identified as Aspergillus niger, Aspergillus oryzae, Neurospora sitophile, Mucor mucedo, Mucor rouxii, Penicilliun notatum, Rhizopus delema, Rhizopus nigricans, Thamnidium elegans, and Tricoderma viridae. When the cellulase activity of fungi isolated from ancient archives and documents was analyzed, Mucor rouxii and Penicilliun notatum showed the highest avicelase and filter paper activity, to 18.089 and 2.819 units, respectively, showing destructive ability of old archives and documents. Whereas, Mucor mucedo revealed the highest CMCase activity of exoglucanase to 7.044 units.

• BMB Reports
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• v.42 no.3
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• pp.131-135
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• 2009

MicroRNAs control gene expression by inhibiting translation or promoting degradation of their target mRNAs. Since the discovery of the first microRNAs, lin-4 and let-7, in C. elegans, hundreds of microRNAs have been identified as key regulators of cell fate determination, lifespan, and cancer in species ranging from plants to humans. However, while microRNAs have been shown to be particularly abundant in the brain, their role in the development and activity of the nervous system is still largely unknown. In this review, we describe recent advances in our understanding of microRNA function at synapses, the specialized structures required for communication between neurons and their targets. We also propose how these advances might inform the molecular model of memory.

• Mycobiology
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• v.31 no.4
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• pp.183-190
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• 2003

Five cereal grains(wheat, barley, rice, maize and sorghum) were collected from three Egyptian provinces known to be grain producers(Daqahlia, Gharbia and Kafer el-Sheikh). Two species of Alternaria(A. raphani and A. tenusinae); two species of Aspergillus(A. flavus and A. niger); one species of Cunninghamella(C. elegans); one Dreschslera species(D. myakt); three Fusarium species(F. graminearum, F. moniliform and F. solani); one Rhizopus species(R. stolonifer) and two species of Penicillium(P. digitatum and P. notatum) were isolated from the grains. The densities of these fungi and their frequencies of occurrence have been investigated. All the fungal isolates were tested for the production of toxic metabolites in culture media and the percentages of toxigenic isolates were calculated. The biological assay of the toxigenic fungal isolates showed significant variations in toxigenic activity. Thin layer chromatography revealed that the most active isolate produces moniliformin in culture media. The effect of culture conditions on the production of moniliformin was studied.

• Journal of Species Research
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• v.6 no.3
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• pp.237-240
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• 2017

During a scientific survey of Korean isopod fauna, we discovered two marine isopods, Limnoria segnoides Menzies, 1957 and Munna japonica Shimomura and Mawatari, 2001, which are new records to South Korea. Limnoria segnoides and M. japonica were collected by SCUBA diving from the subtidal zone of Jeju Island and Yangyang-gun in South Korea, respectively. In this paper, we provide diagnosis and illustrations of the two isopods. Additionally, we provide GenBank accession numbers of partial sequences of mitochondrial cytochrome c oxidase subunit 1 (CO1) of two species.

• ALGAE
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• v.26 no.4
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• pp.333-342
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• 2011

Macroalgae are important primary producers in marine ecosystem. They don't only play an important role as bioindicators but also provide economic resources for humans. Seasonal and vertical variations in seaweed species composition and biomass were examined to determine the ecological status of seaweed beds around Udo, near Jeju Island. We obtained samples at two sites in the high-intertidal to subtidal zones using the quadrat method between June 2010 and May 2011. A total of 262 species were collected, including 31 green, 61 brown, and 170 red algae. The composition of algal species revealed a decrease in species growing in cold water in comparison with the list 20 years ago. The macroalgal mean biomass (g wet wt $m^{-2}$) was 3,476 g and 2,393 g from the two sites, respectively. Ecklonia cava had the greatest biomass at both sites. The seasonal dominant species by biomass at site 1 from the low-intertidal to 1-3 m depth of the subtidal zone was mostly comprised of thick-leathery form, such as Sargassum hemiphyllum, S. coreanum, and Ecklonia cava, whereas site 2 was comprised of the turf form, such as Chondrophycus intermedius, Chondracanthus intermedius, Dictyopteris prolifera, and Gelidium elegans. The current ecological status of the seaweed community in Udo is stable based on diversity and dominance indices.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.24 no.4
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• pp.135-143
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• 1988

To study the abundances of ichthyoplankton in the Nakdong River estuary, ichthyoplankton were sampled with standard net at approximately one month intervals from February, 1987 to January, 1988. Temperature and salinity in the study area showed large seasonal fluctuations due to the inflow of Nakdong River. Among 8 taxa of pelagic eggs occured in the study area, Sillago spp. occupied 37.3% of the total eggs; Coilia spp., 35.8%; Repomucenus spp., 13.7%; Engraulis japonica, 9.4%. These 4 taxa occupied 96.4% of the total eggs. Among 26 taxa of fish larvae, Engraulis japonica was the most abundant species and occupied 36.8% of the total larvae; Gobiidae, 15.3%; Repomucenus spp., 15.0%; Coilia spp., 14.0%; Hexagrammos otakii, 6.8%; Omobranchus elegans, 4.4%. These 6 taxa occupied 92.3% of the total larvae, The densities of pelagic eggs were more than 100 eggs/ 1,000m super(3) from May to October. The densities of larvae were 3.8~221.3 larvae/1,000m super(3). They were relatively high in May, July, and August.

• 한국해양학회지
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• v.8 no.1
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• pp.22-32
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• 1973

Based on the plankton samples collected in the Korea Strait in 1972, a study was conducted on the vertical distribution of chaetognaths in relation to water masses in th Strait. The settling volume of total plankton collected in the Strait ranged from 0.3 to 5 cc/10㎥ and showed a distinctive variation in the vertical distribution between day and night. The large amount of volume was found in the upper layer at night and deeper layer during the day time collections. A total of 19 species and one forma of chaetognaths were identified from the present samples. In general, the number of species and individuals of chaetognaths were abundant in the upper layer. But in August they were distributed almost evenly from the surface to the bottom layer. Particularly several species of warm water chaetognaths, i. e., Sagitta enflata and S. regularis appeared abundantly in the deeper layer in summer. This indicates a sinking phenomenon of warm water from the surface to the bottom layer. As for the vertical distribution of S.elegans, a cold water species, in the Korean Strait, it is restricted only to the bottom layer except in the region of upwelling where they appear in the middle layer. This species is usually distributed in the depth of below 150m in the southern part of Japan Sea(Park, 1970), and it is usually distributed as far south as the Strait between Busan and Tsushima. In addtion, cold water species of copepods such as Pseudocalanus minutus and Metridialucens appear in the western side of Thushima. As indicated by the vertical and horizontal distribution of S. elegans in the Strait, the cold water flows as an undercurrent along the bottom from the southern part of the Japan Sea to the Korea Strait between Busan and Thushima in summer and fall, with a trend of uprising along the coast of Korea. S. decipiens has been found only in the depth of below 50m except in the coastal area where they appear in the upper layer. Therefore the vertical distribution of this species can be used for tracing the occurrence of upwelling and the movement of water from the middle layer.

• Korean Journal of Ecology and Environment
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• v.41 no.1
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• pp.54-65
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• 2008

The seasonal dynamics of phytoplankton and water quality were evaluated bimonthly at 7 park ponds in the capital region from October 2004 to August 2005. With out the change of water temperature $(0.4\sim26.0^{\circ}C)$, cyanobacteria dominated in park ponds such as Gyungbokgung Gyunghyaeru and Seokchon reservoir. The standing crops of phytoplankton was significant related with cell densities of cyanobacteria (r=0.993), while they did not significant correlation with environmental factors. Almost of all park ponds in the capital region were classified as eutrophic state with high TP concentrations and TN/TP ratios less than 10. Major dominant cyanobacteria were as followed; Anabaena sp., Aphanocapsa elachista, Lyngbya contorta, Merismopedia elegans, Microcystis aeruginosa, M. wesenbergii, Microcystis sp., Oscillatoria sp., Phormidium tenue, and Plectonema sp. To date, although the concentration of chlorophyll-${\alpha}$ and cyanobacterial densities in the capital region was below the 'danger' level of WHO guidelines value, the monitoring of cyanobacterial densities and its toxin (microcystin) in recreational/bath water should be continued.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.13 no.4
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• pp.303-307
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• 2008

We investigated about change of dinoflagellate composition during October 2006 to November 2007 at the Chagwi-Do, west-part of Jeju Island. There were 32 dinoflagellate species in collected samples and 19 species Amphisolenia bidentata, Ceratium gravidum, C. hexacanthum, C. platycorne, C. praelongum, C. ranipes, C. reflexum, C. geniculatum, Dissodinium elegans, D. bicorne, Ornithocercus heteroporus, O. magnificus, O. quadratus, O. splendidus, O. steinii, Protoperidinium excentricum, Pseliodinium vaubanii, Ptychodiscus noctiluca, Pyrocystis hamulus of collected dinoflagellate species were rare and unrecorded species from around the Korean Peninsula. The quantities by month of these tropical oceanic species, Ornithocercus were 28, 22, 0, 3 and $502\;cells/m^3$ in October 2006, February, April, September and November 2007 respectively. The abundance of genus Ornithocercus for whole dinoflagellate species were 8, 3.9, 0, 0.2 and 97.9% respectively. These results suggest that the coast of Korean Peninsula is getting warm by global warming.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.47 no.6
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• pp.927-934
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• 2014

Marine algal flora and community structure were seasonally examined at Jungjado, on the southern coast of Korea, from July 2007 to May 2008. A total of 112 seaweeds, including 15 green, 24 brown, and 73 red algae, were identified and 33 species were found throughout the year. The average seaweed biomass was 145.78 g dry weight $m^{-2}$, and the biomass was maximal in winter (184.74 g) and minimal in autumn (106.17 g). The dominant and subdominant species in terms of biomass were Sargassum thunbergii and Grateloupia elliptica in summer, S. thunbergii and Corallina pilulifera in autumn, S. thunbergii and Chondracanthus intermedius in winter, and Sargassum fusiforme and G. elliptica in spring. The vertical distribution patterns of seaweeds from the upper to lower intertidal zones at Jungjado were S. thunbergii - Ulva conglobata - Gelidium elegans in summer; Caulacantus ustulatus - Chondria crassicaulis - C. pilulifera in autumn; Ulva australis - S. thunbergii - G. elliptica in winter; and Gloiopeltis tenax - S. fusiforme - G. elliptica in spring. Seasonally the evenness, richness, and diversity indices tended to have their highest values during the winter and their lowest values in the summer. However, the dominant index was recorded as lowest in winter and highest in the summer. The C/P, R/P, and (R+C)/P values reflecting the flora characteristics were 0.58, 3.04, and 3.62, respectively.