• Development and Reproduction
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• v.17 no.4
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• pp.337-343
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• 2013

Post-thawed larval rearing in Pacific oyster Crassostrea gigas was performed to investigate the survival rate with time course in three kinds of larvae cryopreserved. The highest survival rate and larval activity index (LAI) of post-thawed larvae were obtained from the permeation in 0.2 M sucrose and 2.0 M ethylene glycol (EG) at $-1^{\circ}C/min$ in freezing speed showing the survival rates just after thawing of 63.8% in trochophore, 84.1% in D-shaped veliger and 56.3% in early umbo veliger. In post-thawed larval rearing with food supply, the larvae lasted their lives until 24 hours in trochophore, 75 hours in D-shaped veliger and 57 hours in early umbo veliger. The results suggested that each larval stage post-thawed revealed no more further development to subsequent respective stage.

• Animal Systematics, Evolution and Diversity
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• v.37 no.1
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• pp.1-8
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• 2021

A eunicid polychaete, Marphysa victori Lavesque, Daffe, Bonifácio & Hutchings, 2017 is described for the first time from the intertidal zones of the Korean coasts. It is characterized by having three types of pectinate chaetae (INS, isodont-narrow-slender; AWS, anodont-wide-slender; and AWT, anodont-wide-thick), appearance of pectinate chaetae from chaetiger 2, the chaetae consisted of pectinate and compound spinigers, and pygidium with one pair of pygidial cirri. In genetic analysis based on cytochrome c oxidase subunit I (COI), intra-specific genetic distance between the specimens of M. victori from its type locality, France and Korea are in the range of 0.000-0.013. This paper includes the morphological description and photographs of M. victori new to Korean fauna, with partial sequences of the mitochondrial COI as DNA barcode data on this species.

• Journal of Marine Bioscience and Biotechnology
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• v.14 no.2
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• pp.124-132
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• 2022

By-products from fisheries produced in Korea are of the same industrial material as imported raw materials and are valuable resources for marine bioindustries. Securing raw materials for the mass production of functional materials is one of the main objectives for marine bioindustrial development. The use of fishery by-products as raw materials is anticipated to increase rapidly as the biomarket is growing into a promising industry. In this study, data were acquired from an open-source environment to perform exploratory data analysis, and various visualization methods were used to compare fishery production to the production of marine processed products in the year 2020. This study suggested that the amount of seafood processing, types of processing items, and areas where fishery processing residue is generated, should be able to secure hygienic raw material supply in large quantities. Thus far, it has been found that the Gyeonggi-do and Busan province, where HACCP-certified processing facilities are concentrated, and the local government Seafood Cluster and the Smart Aquaculture Cluster are at the forefront of stable, mass production of raw materials.

• Ocean and Polar Research
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• v.43 no.3
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• pp.149-164
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• 2021

Since the existing mass production and consumption systems are no longer sustainable, countries are pushing for policies to make fisheries by-products as resources in an eco-friendly manner, and international standards are also being strengthened to increase the value of by-products. In Korea, economic and environmental perceptions of the by-products are rapidly changing, such as realizing carbon neutrality and enhancing circular resources by Korean Sustainable Development Goals. Raw materials derived from the by-products have been steadily imported from 2018. In particular, the number of imports of fish collagen peptides was only 16 number of times in 2017, but was rapidly increased to 483 number of times in 2020. Simultaneously, the demand for raw materials and nutrients for health functional food derived from fish by-products, which did not exist statistically until 2017, started to arise from 2018, and in 2019, consumption of high-value-added raw materials for fish by-products increased by 45% compared to the previous year. However, limitations are in legal and biotechnical industry aspects while its value as a biomaterial is recognized in the by-products-related industry. In this study, therefore, the status of by-products for upcycling biomaterials was reported and provided a scientific basis for supporting governmental strategies. In order to fulfill with the principles of a sustainable circular economy, the factors on hinder the marine bio-industrialization of the by-products were derived and suggested directions and plans for development into a high-value added the by-products as the marine bio-industry by substituting imported raw materials to support the development.

• ALGAE
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• v.36 no.3
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• pp.219-229
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• 2021

The hepatoprotective effect of liposoluble portion of Pyropia yezoensis (PYLP) was investigated against alcohol-induced liver injury in mice. Fatty acids were predominant in PYLP obtained from hexane fraction of 70% EtOH extract after ultrasonication. In particular, polyunsaturated fatty acids such as eicosapentaenoic acid and linoleic acid accounted for 56.91% of the total lipids. PYLP significantly reduced liver damage induced by the alcohol treatment in mice. PYLP treatment increased the activity of antioxidant enzymes including superoxide dismutase, catalase, and glutathion peroxidase by reducing thiobarbituric acid reactive substances. Histological observations showed that PYLP minimizes damage to living tissue induced by alcohol treatment by modulating the expression level of proteins involved in the anti-apoptotic signaling pathway. Our results suggest that PYLP, rich in polyunsaturated fatty acids extracted from the red alga P. yezoensis, will be useful as a potential liver protectant in the hangover industry.

• Fisheries and Aquatic Sciences
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• v.17 no.4
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• pp.391-401
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• 2014

Ten feeding trials were conducted to determine and to make the guideline for the optimum feeding rates in olive flounder Paralichthys olivaceus fed extruded pellets at various growth stages at the optimum rearing water temperature. The entire trials were grouped into four growth stages, namely the first stage of juvenile (5 and 9 g), the second stage of juvenile (20, 30, 40 and 50 g), growing (240 and 317 g) and sub-adult (384 and 525 g) stages with 2, 4, 2 and 2 feeding trials, respectively. In the first and second experiments, results indicated that the optimum feeding rates for the first stage of juvenile olive flounder weighing 5 and 9 g could be >5.17 but <5.52% and >4.44 but <4.64% body weight (BW)/day, respectively. In the third, fourth, fifth and sixth experiments, results suggested that the optimum feeding rates for the second stage of juvenile olive flounder weighing 20, 30, 40 and 50 g could be >3.47 but <3.50, >2.85 but <3.53, >2.58 but <3.04 and >2.36 but <2.50% BW/day, respectively. In the seventh and eighth experiments, results showed the optimum feeding rates for growing olive flounder weighing 240 and 317 g to be >1.03 but <1.25 and >0.85 but <1.0 % BW/day, respectively. In the ninth and tenth experiments, the optimum feeding rates in sub-adult olive flounder weighing 384 and 525 g were shown to be >0.69 but <0.7 and >0.55 but <0.8% BW/day, respectively. We will compare these results with the previous studies done by other research groups.

• Journal of Marine Bioscience and Biotechnology
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• v.6 no.2
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• pp.84-101
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• 2014

The aim of this project is to develop an adaptive and collective National Marine Biotechnology Plan for the next decade(2014~2023) which is able to reflect current and future changing environment. This effective strategy targets to foster marine-derived active bio-materials, marine bioenergy production technology and many promising technologies in order to promote marine biotechnology industry as a next-generation growth engine. Marine biotechnology industry based on R&D activities since 1980 has been growing as an emerging industry. This new field enables to secure exclusive patent rights and to find new potential bio-active materials from the ocean that requires long-term aggressive R&D investments. The current policy direction is to raise appropriate level of R&D investment because the current Korea's national marine biotechnology R&D fund ratio is less than 2% of the total national biotechnology R&D budget. The result shows three major strategies. First, it recommended a research implementation system and supporting policy that includes establishment of open innovation framework for the 'Industry-Academia-Research Institute Collaborations', strategic research planning and enhanced policy making process. Second, it derived state-of-the-art or new technology in many areas. Third, it formulated more detailed execution plans for successful R&D support and set up performance indicator system in related R&D program.

• Asian-Australasian Journal of Animal Sciences
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• v.25 no.2
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• pp.272-277
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• 2012

Compensatory growth of grower olive flounder (Paralichthys olivaceus) was determined at suboptimal temperature ($13.0{\pm}1.9^{\circ}C$). Fifteen fish averaging 201.1 g per tank were distributed into 18 of 300 L flow-through tanks. Six treatments were prepared in triplicate: fish were hand-fed with an extruded pellet to apparent satiation once a day for 16 weeks (16 WF); and the other five groups of fish were hand-fed for 15, 14, 13, 12 and 10 weeks after 1-, 2-, 3-, 4- and 6-week feed deprivation, referred to as 15 WF, 14 WF, 13 WF, 12 WF and 10 WF, respectively. A linear relationship between body weight of fish and feed deprivation was observed: Y (Body weight of fish) = -1.81X (Weeks of feed deprivation)+201.07, $R^2$ = 0.83. Weight gain of grower olive flounder in 15 WF, 14 WF, 13 WF and 12 WF treatments was comparable to that of fish in 16 WF treatment, but lower than that of fish in 10 WF treatment. Specific growth rate of fish in 15 WF treatment was higher than that of fish in 16 WF, 14 WF and 10 WF treatments. Feed consumption of fish was not affected by feeding regime. Feed and protein efficiency ratios of fish in 15 WF treatment were higher than those of fish in 13 WF, 12 WF and 10 WF treatments. Grower olive flounder could achieve full compensatory growth when fish were daily fed for 12 weeks after 4-week feed deprivation at suboptimal temperature.

• Fisheries and Aquatic Sciences
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• v.14 no.2
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• pp.148-160
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• 2011

Thirty-one gross abnormalities that have been observed in tilapia are described: 10 fin, five eye, five jaw, four body shape, three head, two yolk sac, one operculum, and conjoined twins. Twenty-one have been described in published papers; the others were obtained from a survey. Breeding experiments revealed that three were heritable, while six were not heritable. Five could be caused by a bacterial infection, and one could be produced by a fungus. Four deformities were in offspring of males that had been injected with methyl methane sulphonate. Three were produced when sperm was treated with methyl methane sulphonate. Six were observed during sex reversal studies, and one was found following heat shock of fertilized eggs. Three were observed in polluted river water. The cause of other deformities is not known.

• Bulletin of the Korean Chemical Society
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• v.34 no.6
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• pp.1867-1870
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• 2013