• The Korean Journal of Malacology
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• v.32 no.1
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• pp.63-65
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• 2016

Carbonic anhydrase (CA), which is involved in shell formation processes in bivalves, is one of the major biocatalysts for carbon capture and storage. In this study we investigated CA activity in the total hemocytic proteins of five bivalves. The highest CA activity was observed in Scapharca broughtonii, which had more than twice the activity found in Crassostrea gigas. No CA activity was observed among the total hemocytic proteins of Pinctada fucata and Saxidomus purpuratus. The results suggest that marine invertebrates may provide a better source of CA, as an alternative to mammalian sources.

• Journal of Fisheries and Marine Sciences Education
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• v.27 no.1
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• pp.170-183
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• 2015

The objectives of this study is to analyze the competitiveness of fisheries trade between Korea and China, and to estimate strategic seafood export products for Korea-China FTA in fisheries sector. The results of analyses indicate that Korea has comparative advantages in export items such as spanish mackerel, flatfish, cod, roe in frozen fish(0303), and squid, sea cucumber, oyster in molluscs(0307). In addition, tuna in prepared or preserved fish(1604), sea cucumber in crustacean, molluscs and other aquatic invertebrates(1605) have comparative advantage in exporting to China.

• Korean Journal of Microbiology
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• v.8 no.4
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• pp.141-150
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• 1970

As a part of taxonomical and ecological studies on the yeasts in marine environments, several kinds of yeasts were isolated from Zostera marina several invertebrates (penaeus, Meretrix and Neptunus) and surface sea water, which are collected at the two established sites of estuarine areas ; Dolsan isaland in Youchun district and Baiksu-ri in Youngkwang district. The obtained results can be summarized as follows. 1. Ascosporgenous Yeasts. Hansenula sp I and Hansenula sp II were isolated from Zotera marina and Hanse nular sp I from penaeus. 2. Asporogenous Yeasts. Trichoporon fermentans, Torulopsis, ernobii and Toruopsis dattia were isolated from Zostera marina, Candida krusei from Meretrix and Neptunus, Torulopsis pinus from surface sea waters, and Phodotorula aurantiaca from Penaeus. 3. More notable isolations of several species from Zostera marina than the other sources could be assumed as related to the higher sugar concentration of this plant.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.46 no.1
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• pp.1-9
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• 2013

Fisheries' biological resources were considered public resources before the 1990s. Every country could access and use these resources without regulation. However, the United Nations adopted the Convention on Biological Diversity and the privileges and rights to these resources were attributed to countries. This research starts with the research background and social and academic value of "The Jasan Eobo (or Report on Marine Organisms in the Coastal Waters near Heuksan Island)" by Jeong Yak-Jeon, who pioneered the new field of Fisheries Science and Marine Biology in Korea in the early 1800s. We also searched for recent results from the Marine Bio-Diversity Research Activities of the Korean National Council for Conservation of Nature (KNCCN) and the Ministry of Maritime Affairs and Fisheries (MOMAF). KNCCN reported that marine bio-diversity comprised approximately 6,500 species in 1996, and the Ministry of Maritime Affairs and Fisheries reported there were about 10,000 species in 2007. Among these marine species, plankton account for about 25%, seaweeds 11%, invertebrates 52%, and vertebrates 12% in Korean Coastal Areas. The Ministry for Food, Agriculture, Forestry, and Fisheries (MIFAFF) enacted a law for Agriculture and Fisheries Resources Management in 2012; this law includes the preservation of marine ecosystems, the conservation of wetlands and the preservation of fisheries resources, and describes the boundary of taxonomy for new species and unknown species that could be identified in the near future. To follow the new regulation for Access to General Resources and Benefit-Sharing, this research suggests (1) the importance of taxonomy for new species and unknown species as a goal of "No Name = No Information", (2) integrated research on bio-diversity, species distributions and the abundance of fisheries resources, both in local areas and in Korean Coastal Areas, and (3) the observance of international regulations or agreements for benefit-sharing without additional damage in the future.

• Molecules and Cells
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• v.27 no.5
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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].

• Journal of the Korean Society of Marine Environment & Safety
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• v.19 no.2
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• pp.186-192
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• 2013

Because of the shallow depth of 44 m and large area of wetland in Korea and China, the class I productivity of Yellow Sea is very high (>300 $gC/m^2/year$), which is supporting substantial populations of fish, invertebrates, marine mammals and seabirds. However, the Yellow Sea is a large marine ecosystem which is enclosed by mainland of China and Korean peninsula, so it is vulnerable to external stress such as environmental degradation and overfishing. Recently, since the Fisheries Agreement between Korea and China, overfishing and illegal fishing of China and environmental degradation caused by coastal development in Korea and China have given much stress to the marine ecosystem of Yellow Sea. This article suggests that the major factors of governance are ineffectively responding to the growing demand for exploitation of the Yellow Sea and the international cooperation for establishing network of Yellow Sea governance is urgent.

• The Korean Journal of Malacology
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• v.31 no.3
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• pp.165-170
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• 2015

The presence of predators (excluding starfishes) of disk abalone, Haliotis discus hannai was directly investigated by nine SCUBA divings during February-December 2014 at the coastal areas of Yangjeong, Jukjin and Bongpyeong, Uljin, Korea, where the young disk abalone seedlings were artificially released. The results revealed that a total of six individuals of Neptunea cumingii that were feeding on the young disk abalone were observed within the water depth 10m at the coastal area of Jukjin, of which bottom substrate consists of the relatively high composition rate of rocks (60.3%). Though N. cumingii is well known as a carnivorous predator of diverse marine invertebrates such as live mussels (Mytilus spp.) it is the first report that this predator also feeds on the disk abalones. Thus, our results strongly suggest that the future artificial release projects around Korean coasts necessitate extermination works of predators including newly observed N. cumingii in this study as well as previously known starfishes prior to the releases of young Pacific abalone seedlings.

• Journal of Food Hygiene and Safety
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• v.33 no.3
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• pp.151-156
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• 2018

The world is becoming overwhelmed with widespread diseases as antibiotic resistance increases at an alarming rate. Hence, there is a demanding need for the discovery and development of new antimicrobial drugs. The ocean is gifted with many organisms like phytoplankton, algae, sponges, cnidarians, bryozoans, mollusk, tunicates and echinoderms, which are known to produce a wide variety of bioactive secondary metabolites with pharmacological properties. Many new therapeutic drugs have emerged from marine invertebrates, although the large algal community is yet to be explored. The bioactivity possessing secondary metabolites of marine algae include polyphenols, phlorotannins, alkaloids, halogenated compounds, sulfated polysaccharides, agar, carrageenan, proteoglycans, alginate, laminaran, rhamnan sulfate, galactosylglycerol, and fucoidan. These metabolites have been found to have great antimicrobial activities against many human aliments. Studies show that the algal community represents about 9% of biomedical compounds obtained from the sea. This review looks at the evolution of drugs from the ocean, with a special emphasis on the antimicrobial activities of marine algae.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.36 no.5
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• pp.469-473
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• 2003

Transplantation of Sargassum horneri to natural substrate using the rope seeding method was undertaken. Seeding of S. horneri was grown on net in an indoor tank up to 0.2-0.3 cm in frond length for 2 months, and then transplanted to an architecture tile $(10\times10\;cm)$ with underwater glue and an iron pipe. After two months, number of S. horneri on the tile decreased because of grazing by herbivores. However, S. horneri on the iron pipe grew up to 0.5-2.0 cm in frond length. After 7 months, they rapidly grew up to a frond length of 11.0-203.0 cm with a mean frond length of 122.6 cm. S. horneri grew up to a maximum frond length of 313.0 cm, and mean frond length of 228.0 cm, after 10 months. The artificial S. hornevi beds can be used to clean the seawater and also be utilized as a source of marine biomass as well as for supplying habitat, shelter and spawning beds for fish and invertebrates.

• Journal of Microbiology and Biotechnology
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• v.15 no.3
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• pp.665-671
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• 2005

Initiation and activation of sperm motility are prerequisite processes for the contact and fusion of male and female gametes at fertilization. The phenomena are under the regulation of cAMP and $Ca^{2+}$ in vertebrates and invertebrates. Mammalian sperm requires $Ca^{2+}$ and cAMP for the activation of sperm motility. Cell signaling for the initiation and activation of sperm motility in the ascidians and salmonid fishes has drawn much attention. In the ascidians, the sperm-activating and attracting factors from unfertilized egg require extracellular $Ca^{2+}$ for activating sperm motility and eliciting chemotactic behavior toward the egg. On the other hand, the cAMP-dependent phosphorylation of protein is essential for the initiation of sperm motility in salmonid fishes. A decrease of the environmental $K^+$ concentration surrounding the spawned sperm causes $K^+$ efflux and $Ca^{2+}$ influx through the specific $K^+$ channel and dihydropyridine-sensitive L-/T-type $Ca^{2+}$ channel, respectively, thereby leading to the membrane hyperpolarization. The membrane hyperpolarization induces synthesis of cAMP, which triggers further cell signaling processes, such as cAMP-dependent protein phosphorylation, to initiate sperm motility in salmonid fishes. This article reviews the studies on the physiological mechanisms of sperm motility and its cell signaling in aquatic species.