• 한국수산과학회지
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• 제48권4호
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• pp.507-528
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• 2015

The Fish Collection Project collected 356 fish species from the Southern Sea of Korea during 2010-2012, 55 more than previously collected. The fishes belonged to 3 classes, 29 orders and 128 families. The 5 dominant orders, Perciformes, Scorpaeniformes, Pleuronectiformes, Tetraodontiformes, and Clupeiformes, accounted for ~80% of the identified species. Additionally, 126 species were collected from the Southern Sea for the first time, while 85 species that had been found in previous collections were not seen. The species variety of fish in the Southern Sea may be influenced by its unique oceanographic conditions such as increased water temperatures in coastal areas, so regular surveys would assist our understanding of the fish community. We suggest that various collection methods, including diving, be used to collect fish species inhabiting rocky shore or deep-sea areas, where commercial fishing gear is difficult to deploy.

• 한국태양에너지학회 논문집
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• 제36권1호
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• pp.19-26
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• 2016

Biomass has been used for energy sources from the prehistoric age. Biomass are converted into solid, liquid or gaseous fuels and are used for heating, electricity generation or for transportation recently. Solid biofuels such as bio-chips or bio-pellet are used for heating or electricity generation. Liquid biofuels such as biodiesel and bioethanol from sugars or lignocellulosics are well known renewable transportation fuels. biogas produced from organic waste are also used for heating, generation and vehicles. Biomass resources for the production of above mentioned biofuels are classified under following 4 categories, such as forest biomass, agricultural residue biomass, livestock manure and municipal organic wastes. The energy potential of those biomass resources existing in Korea are estimated. The energy potential for dry biomass (forest, agricultural, municipal waste) were estimated from their heating value contained, whereas energy potential of wet biomass (livestock manure, food waste, waste sludge) is calculated from the biological methane potential of them on annual basis. Biomass resources potential of those 4 categories in Korea are estimated to be as follows. Forest biomass 355.602 million TOE, agricultural biomass 4.019 million TOE, livestock manure biomass 1.455 million TOE, and municipal organic waste 1.074 million TOE are available for biofuels production annually.

• The Korean Journal of Ecology
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• 제25권1호
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• pp.59-62
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• 2002

Dokdo, which is located in the middle of the East Sea, is a small island tilth a total area of 0.186 $\textrm{km}^2$. However, this small island, with its mild oceanic climate, has rich bio-resources and picturesque natural surroundings. Dokdo in the crystaline waters and In the central area of the deep sea is a treasury of algaes (sea oak, sea mustard, gulf weed, laver, agar-agar, etc.), molluscs (squid, ear shell, conch, etc.) and fishes (Alaska pollack, anchovy, saucy, herring, etc.). On the other hand, there are a lot of grasses and various kinds of grasses on the land of Dokdo. And a lot of back-tailed gulls (about 20,000 Individuals) live on this island. There have been disputes on the sovereignty over Dokdo between Korea and Japan. Japan has claimed sovereignty over Dokdo since Japan incorporated the island into Japanese territory in 1905 when it occupied the Korean Peninsula by force. Korea governed Dokdo not only before 1905 but also after its liberation in 1945. The Korean government, while heavily financing building facilities like pleas and quays, is endeavoring to preserve the natural surroundings of this island.

• Animal Systematics, Evolution and Diversity
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• 제37권4호
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• pp.354-357
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• 2021

In Korean waters, the cirolanid isopod, Eurydice longiantennata Nunomura and Ikehara, 1985 has been reported only from the subtidal zone of Jeju island. We obtained the mitochondrial cytochrome c oxidase subunit I (COI) sequences of this species and determined the DNA barcoding data of E. longiantennata based on a genetic comparison of E. longiantennata and its congeners. The intra-specific genetic distance between the three COI sequences of E. longiantennata ranged from 0 to 0.6%. The inter-specific distances between E. longiantennata and other cirolanid isopods ranged from 24 to 33.2%. In this study, we provided the DNA information of E. longiantennata with a morphological diagnosis and images of the species.

• Animal Systematics, Evolution and Diversity
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• 제38권2호
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• pp.108-112
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• 2022

An aegid species, Rocinela niponia Richardson, 1909, is a Far Eastern species known from Korean and Japanese waters. In this study, mitochondrial cytochrome c oxidase subunit I (COI) sequences of R. niponia were determined based on four specimens collected from the subtidal zone of Chujado Island, South Korea. We compared DNA barcoding data of this species with its congeners. As a result, there was no intra-specific genetic distance between the four COI sequences of R. niponia. Inter-specific distances between R. niponia and other five aegid species ranged from 23.8% to 35.6%. Morphological diagnosis and images of R. niponia are also provided as a valuable contribution toward the identification of Rocinela species in further taxonomic and ecological studies.

• 한국자원식물학회:학술대회논문집
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• 한국자원식물학회 2021년도 춘계학술대회
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• pp.10-10
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• 2021

Natural products have been used as drugs and cosmetics due to their bioactivity and their biochemical diversity. Natural products usually refer to secondary metabolites produced by various living organisms including marine animals, insects, microbes, amphibians, and plants. These secondary metabolites, which usually have molecular weights less than 2,000 amu, are unnecessary for survival, development, growth, and reproduction but play major roles in plant defense systems against other species. These secondary metabolites such as lignans, flavonoids, monoterpenes, and phenylethanoid glycosides showed various biological activities like anti-oxidant behavior, anti-cancer properties, neuroprotective properties, and so forth. Thus, isolation and elucidation of secondary metabolites from living organisms is of great significance to human life.

• Animal Systematics, Evolution and Diversity
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• 제40권1호
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• pp.35-41
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• 2024

Two species belonging to the genus Gregarinidra Barroso, 1949 (Bryozoa: Gymnolaemata: Flustridae) were first found in this study from Korean waters. Gregarinidra furcula n. sp. is new to science, and G. incrustans (Silén, 1941) is newly added to the Korean fauna. Species belonging to this genus are primarily distinguished by two characteristics: interzooidal avicularia and marginal spines. The pitchforked spines clearly distinguish G. furcula n. sp. from the other Gregarinidra species, and G. incrustans shows the difference by having blunt spines and short-triangular avicularia. Gregarinidra incrustans was known to be distributed only in Japan until this species was reported from the South Sea, Korea, in the present study. This study provides descriptions of two species with detailed illustrations by scanning electron microscopy, distributional data, and a taxonomic key to the Korean Gregarinidra species. With the addition of two species reported herein, four Korean Gregarinidra are recorded: G. corbula Seo, 1996, G. furcula new species, G. incrustans(Silén, 1941), and G. serrata (MacGillivray, 1869). Finally, Gregarinidra totals 10 species worldwide.

• Animal Systematics, Evolution and Diversity
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• 제40권1호
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• pp.73-78
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• 2024

A taxonomic study of the family Electridae Stach, 1937 (Bryozoa: Cheilostomatida) was carried out using materials collected from six localities of Korea from 1984 to 2021. Aspidelectra melolontha (Landsborough, 1852) is newly added to the bryozoan fauna of Korea, and Electra jindoica n. sp. is new to science. European A. melolontha is known to occur in brackish water of low salinity, but the species is found in New Zealand and Argentina seawater. This species is also reported as a fouling bryozoan from China and New Zealand. Electra jindoica n. sp. is distinguished by smaller zooid, larger kenozooid, and developed cryptocyst from E. asiatica Grischenko, Dick and Mawatari, 2007. With the addition of two species reported herein, six species and four genera of Electridae from Korea have been recorded: Aspidelectra melolontha, Arbopercula tenella, Conopeum hexagonum, C. reticulum, C. seurati, and Electra jindoica n. sp. Furthermore, the genera Aspidelectra and Electra are new to the Korean bryozoan fauna based on this study.

• 한국축산식품학회지
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• 제26권3호
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• pp.402-409
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• 2006

Although microorganisms are, in fact, the most diverse and abundant type of organism on Earth, the ecological functions of microbial populations remains poorly understood. A variety of bacteria including marine Vibrios encounter numerous ecological challenges, such as UV light, predation, competition, and seasonal variations in seawater including pH, salinity, nutrient levels, temperature and so forth. In order to survive and proliferate under variable conditions, they have to develop elaborate means of communication to meet the challenges to which they are exposed. In bacteria, a range of biological functions have recently been found to be regulated by a population density-dependent cell-cell signaling mechanism known as quorum-sensing (QS). In other words, bacterial cells sense population density by monitoring the presence of self-produced extracellular autoinducers (AI). N-acylhomoserine lactone (AHL)-dependent quorum-sensing was first discovered in two luminescent marine bacteria, Vibrio fischeri and Vibrio harveyi. The LuxI/R system of V. fischeriis the paradigm of Gram-negative quorum-sensing systems. At high population density, the accumulated signalstrigger the expression of target genes and thereby initiate a new set of biological activities. Several QS systems have been identified so far. Among them, an AHL-dependent QS system has been found to control biofilm formation in several bacterial species, including Pseudomonas aeruginosa, Aeromonas hydrophila, Burkholderia cepacia, and Serratia liquefaciens. Bacterial biofilm is a structured community of bacterial cells enclosed in a self-produced polymeric matrix that adheres to an inert or living surface. Extracellular signal molecules have been implicated in biofilm formation. Agrobacterium tumefaciens strain NT1(traR, tra::lacZ749) and Chromobacterium violaceum strain CV026 are used as biosensors to detect AHL signals. Quorum sensing in lactic acid bacteria involves peptides that are directly sensed by membrane-located histidine kinases, after which the signal is transmitted to an intracellular regulator. In the nisin autoregulation process in Lactococcus lactis, the NisK protein acts as the sensor for nisin, and NisR protein as the response regulator activatingthe transcription of target genes. For control over growth and survival in bacterial communities, various strategies need to be developed by which receptors of the signal molecules are interfered with or the synthesis and release of the molecules is controlled. However, much is still unknown about the metabolic processes involved in such signal transduction and whether or not various foods and food ingredients may affect communication between spoilage or pathogenic bacteria. In five to ten years, we will be able to discover new signal molecules, some of which may have applications in food preservation to inhibit the growth of pathogens on foods.

• Molecules and Cells
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• 제27권5호
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• pp.515-523
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• 2009

To infer the monophyletic origin and phylogenetic relationships of the order Desmoscolecida, a unique and puzzling group of mainly free-living marine nematodes, we newly determined nearly complete 18S rDNA sequences for six marine desmoscolecid nematodes belonging to four genera (Desmoscolex, Greeffiella, Tricoma and Paratricoma). Based on the present data and those of 72 nematode species previously reported, the first molecular phylogenetic analysis focusing on Desmoscolecida was done by using neighbor joining (NJ), maximum parsimony (MP), maximum likelihood (ML) and Bayesian inference (BI) methods. All four resultant trees consistently and strongly supported that the family Desmoscolecidae forms a monophyletic group with very high node confidence values. The monophyletic clade of desmocolecid nematodes was placed as a sister group of the clade including some members of Monhysterida and Araeolaimida, Cyartonema elegans (Cyartonematidae) and Terschellingia Iongicaudata (Linhomoeidae) in all the analyses. However, the present phylogenetic trees do not show any direct attraction between the families Desmoscolecidae and Cyartonematidae. Within the monophyletic clade of the family Desmoscolecidae in all of the present phylogenetic trees, there were consistently observed two distinct subgroups which correspond to the subfamilies Desmoscolecinae [Greeffiella sp. + Desmoscolex sp.] and Tricominae [Paratricoma sp. + Tricoma sp].