• 한국동물생명공학회지
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• 제39권1호
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• pp.19-30
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• 2024

Background: Although an understanding of the proliferation and differentiation of fish female germline stem cells (GSCs) is very important, an appropriate threedimensional (3D) research model to study them is not well established. As a part of the development of stable 3D culture system for fish female GSCs, we conducted this study to establish a 3D aggregate culture system of ovarian cells in marine medaka, Oryzias dancena. Methods: Ovarian cells were separated by Percoll density gradient centrifugation and two different cell populations were cultured in suspension to form ovarian cell aggregates to find suitable cell populations for its formation. Ovarian cell aggregates formed from different cell populations were evaluated by histology and gene expression analyses. To evaluate the media supplements, ovarian cell aggregate culture was performed under different media conditions, and the morphology, viability, size, gene expression, histology, and E2 secretion of ovarian cell aggregates were analyzed. Results: Ovarian cell aggregates were able to be formed well under specific culture conditions that used ultra-low attachment 96 well plate, complete mESM2, and the cell populations from top to 50% layers after separation of ovarian cells. Moreover, they were able to maintain minimal ovarian function such as germ cell maintenance and E2 synthesis for a short period. Conclusions: We established basic conditions for the culture of O. dancena ovarian cell aggregates. Additional efforts will be required to further optimize the culture conditions so that the ovarian cell aggregates can retain the improved ovarian functions for a longer period of time.

• Journal of Microbiology and Biotechnology
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• 제23권4호
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• pp.437-443
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• 2013

The diversity of culturable non-actinobacterial (NA) bacteria associated with four species of South China Sea gorgonians was investigated using culture-dependent methods followed by analysis of the bacterial 16S rDNA sequence. A total of 76 bacterial isolates were recovered and identified, which belonged to 21 species of 7 genera, and Bacillus was the most diverse genus. Fifty-one percent of the 76 isolates displayed antibacterial activities, and most of them belonged to the Bacillus genus. From the culture broth of gorgonian-associated Bacillus methylotrophicus SCSGAB0092 isolated from gorgonian Melitodes squamata, 11 antimicrobial lipopeptides including seven surfactins and four iturins were obtained. These results imply that Bacillus strains associated with gorgonians play roles in coral defense mechanisms through producing antimicrobial substances. This study, for the first time, compares the diversity of culturable NA bacterial communities among four species of South China Sea gorgonians and investigates the secondary metabolites of gorgonian-associated B. methylotrophicus SCSGAB0092.

• Journal of Microbiology and Biotechnology
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• 제18권6호
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• pp.1115-1120
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• 2008

A novel cathepsin B inhibitor-producing bacterium was isolated from marine sediments and identified based on its 16S rDNA sequence as Pseudomonas sp. strain PB01 (Accession No. EU126129). The growth and enzyme inhibitor production were investigated under various culture conditions. A mixture of organic nitrogen source was required for the optimal production, whereas both glucose and maltose proved to be the effective carbon sources for cathepsin B inhibitor production. Other optimal culture conditions included temperature range between 25 and $28^{\circ}C$, initial medium pH of 6.6, and shaking speed of 200 rpm. Under these optimal conditions, the maximum inhibitory activity from culture broth was approximately 50% after 30 h of cultivation. Additionally, kinetic study revealed that inhibitor production paralleled with cell growth, which suggested that the inhibitor may be a primary metabolite of that bacterium.

• 수산해양교육연구
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• 제28권6호
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• pp.1724-1738
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• 2016

This paper was researched on economic feasibility and sensibility of operation to offshore cage culture for cod. Offshore cage culture for cod needs to invest high budget what to construction and operation. And it was required variety methods about analysis of economic feasibility. Therefore, these were studied NPV, B/C and sensitivity for each by assuming a six scenarios considering the product performance according to the size of cod and culturing methods of fingerlings, etc. As a results, even though economy, if efficiency is low, it is a priority need the technical development to promote the feed efficiency to increase economic feasibility and should make efforts to enhance the business economy to strengthen the price competitiveness pricing with high quality products through quality control and brand recognition of cod. It expects to be used as a reference for related research in the future by deriving policy implications based on the method of analysis of the economic feasibility on offshore cage culture for cod.

• 해양환경안전학회지
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• 제21권3호
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• pp.283-289
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• 2015

This paper provides a study on the application and proposals of safety culture, new public management and social amplification of risk framework via ship accidents in Korea. This document analyzes what are the concept of safety culture, new public management as well as social amplification and risk framework and describes how 3 issues act, harmonize, interrelate through M/V Sewol accident. Korean government is needed to apply social amplification of risk framework to the in order to promote the safety culture in the maritime administration. Hence, this paper proposes safety framework in order to prevent and resolve future unexpected accident especially for maritime field.

• 수산해양교육연구
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• 제25권1호
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• pp.246-259
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• 2013

The principal purpose of this study is to analyze school organizational culture in secondary school in Busan. This study measures background variables such as gender, teaching experience, classification of school, grade of school, and scale of school. The results of the study are as follows : First, to see the difference on the perception of organizational culture depending on gender, female teachers have a stronger sense of professionalism, community spirit and consideration than male teachers. Second, to see the difference on the perception of organizational culture in terms of teaching experience, teachers who have more than 21 years of teaching experience have a more positive perception on decision-making and consideration than those who have 11~20 years of teaching experience. Third, to see the difference on the perception of organizational culture according to classification of school, public schools have a more positive perception on every item such as professionalism, decision-making, community spirit, and consideration than private school. Fourth, to see the difference on the perception of organizational culture in terms of classification of schools, secondary schools have a more positive perception on professionalism and community spirit than high schools. Lastly, as it is seen in the difference on the perception of organizational culture depending on scale of school, schools which have 13~35 classes have a more positive perception on professionalism than others.

• 한국조리학회지
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• 제14권2호
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• pp.293-302
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• 2008

The objective of this study is to suggest development methods of marine tour complexes by specializing and modernizing the renowned Jagalchi Fish Market. This study tries to suggest the ways of overcoming limitations of the traditional market place and making a unique tourism destination with affluent attractive culture elements. To preserve its position as the most famous fish market in Korea, Jagalchi market needs to more differentiate its position over competitors. To do that, it needs to avoid over-lapping of product categories among different sectors and specializing each zone according to the assigned theme. Improving tourism environments by expanding entertaining aspects, building landmark facilities and a seaside park, and tourism infrastructures. In addition, the development scheme needs to be planned unified with other city development plans to create a unified image, and a connection program with other tourism resources surrounding the target area needs to be created in order to pursue synergy effects. In the aspect of food, a large seafood center which offers various seafood from all around the world, a traditional night market street, various theme restaurants can be suggested. Successful development of the Jagalchi marine tour complexes not only has ripple effects on the region's culture, society, and other related industries but directly influences related regional tourism and commercial industry.

• 한국항해항만학회지
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• 제33권2호
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• pp.161-166
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• 2009

Lactobacillus sp., Acetobacter sp. and yeast were the most dominant organisms in the EM stock culture and subculture product. Lactic acid bacteria and yeast were able to grow in the fermentation process utilizing seawater. EM treatment of higher concentrations using EM stock culture and EM clay balls (1% or 4%) contributed to an early removal of malodor and an increase of DO in the polluted sediments, indicating an odor-removing activity of EM. The EM treatment of higher concentrations (1% or 4%) somewhat appeared to modify the microbial communities within the sediments, which was confirmed by existence of a few unique fragments from the stock culture based on PCR-DGGE. It still remains to be elucidated that EM cultures were directly involved in the malodor removal and potential sediment bioremediation.

• The Plant Pathology Journal
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• 제24권4호
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• pp.461-468
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• 2008

An endophytic bacterial strain YC5480 producing antifungal and phytotoxic compounds simultaneously was isolated from the surface sterilized root of Artemisia sp. collected at Jinju area, Korea. The bacterial strain was identified as a species of Pseudomonas brassicacearum based on its 16S rRNA gene sequence analysis and physiological and biochemical characteristics. The seed germination and growth of monocot and dicot plants were inhibited by culture filtrate (1/10-strength Tryptic Soy Broth) of the strain. The germination rate of radish seeds in the culture filtrate differed in various culture media. Only 20% of radish seeds germinated in the culture media of 1/2 TSB for 5 days incubation. Mycelial growth of fungal pathogens, Colletotrichum gloeosporioides, Fusarium oxysporum and Phytophthora capsici was also inhibited by the culture filtrate of the strain YC5480. An antifungal compound, KS-1 with slight inhibitory activity of radish seed germination at 1,000 ppm and a seed germination inhibitory compound, KS-2 without suppression of fungal growth were produced simultaneously in TSB. The compounds KS-1 and KS-2 were identified to be 2,4-diacetylphloroglucinol (DAPG) and 2,4,6-trihydroxyacetophenone (THA), respectively.

• 한국수산과학회지
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• 제50권5호
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• pp.500-505
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• 2017

The nucleotides and their related compounds, including ATP (adenosine triphosphate), ADP (adenosine diphosphate), AMP (adenosine monophosphate), IMP (inosine monophosphate), HxR (inosine) and Hx (hypoxanthine), were nearly identical in oysters Crassostrea gigas from the two culture methods. The K-value was lower than the threshold value such as 11.2-12.1. Although oysters have low amount of IMP, it was detected in this experiment. DPPH radical scavenging activity did not vary significantly with sample amounts (100, 300, and $500{\mu}g/mL$). DPPH (1,1-diphenyl-2-picryl-hydrazyl) radical scavenging activity was 76.0-80.7% compare with the ascorbic acid standard. Superoxide anion scavenging activity reached 49.3% in the rack-and-bag culture sample at $500{\mu}g/mL$. However, the reducing power and $Fe^{2+}$ chelating activity were very low compared with their respective standard. The oyster culture methods did not affect oyster quality in terms of antioxidant activities.