• Journal of Species Research
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• v.12 no.spc
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• pp.1-69
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• 2023

This study aims to establish a comprehensive, synthetic inventory system for the fauna and flora of Dokdo Island, Republic of Korea, which has been conducted by a specialized research group consisting of more than 50 experts. The research was conducted over five years(2015-2019) and supported by the National Institute of Biological Resources, Ministry of Environment, Republic of Korea. All possible publications on the fauna and flora of Dokdo Island over the last 68 years from 1952 to 2020 were reviewed. As a result, 1,302 species were found on Dokdo Island during the study period. An updated list of 1,963 species was created. This is expected to be of great help for the conservation and national publicity of important indigenous biological resources of Dokdo Island.

• Journal of Life Science
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• v.20 no.2
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• pp.190-196
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• 2010

Nowadays many people use antibiotics to protect processed foods from many pathogenic bacteria. The abuse of antibiotics, however, can run the risk of creating resistant forms of bacterium. Our study focus is on making new substances that can not only replace antibiotics but also be friendly to the environment. In our experiments, we used fermented citrus fruit, soil microbes and coenzyme Q10 as probiotics and prebiotics. Chickens in the experimental group were fed these substances via oral route while those in the control group were not. After specific time periods, blood and feces samples were collected to test for Salmonella spp.. It is interesting that fermented citrus fruit was the most effective in suppressing this bacterium. Furthermore, dissection of the experiment group chickens shows that their livers did not change to a yellow color, in contrast to the control group. The results confirmed our proposal that the chickens fed with these materials can be protected from infection by Salmonella and other pathogens. These probiotics and prebiotics are highly practical because they are natural substances that can be easily recycled in the environment. It can also be used as an animal feed ingredient because of its safety.

• Food Science of Animal Resources
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• v.27 no.3
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• pp.267-276
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• 2007

This study was conducted to determine the effect of cryoprotectants (sugar, sorbitol, polyphosphate) on the physico-chemical characteristics of chicken breast surimi manufactured by pH adjustment (pH 11.0) during freezing storage. The final surimi was divided into experimental units to which the following treatments were randomly assigned: C (Alaska pollack surimi: two washings, 4% sugar +5% sorbitol ${\pounds}'$ 0.3% polyphosphate additive): T1 (chicken breast surimi: pH 11.0 adjusted, 0.3% polyphosphate additive): T2 (chicken breast surimi pH 11.0 adjusted, 5% sorbitol +0.3% polyphosphate additive); T3 (chicken breast surimi: pH 11.0 adjusted, 4% sugar +5% sorbitol +0.3% polyphosphate additive). The crude protein content of the control was higher than all treated samples, however the moisture, crude fat and crude ash of T3 were higher than the control (p<0.05). The pH, WHC and collagen content of the control were higher than all of the treated samples, and these values decreased with storage time for all treatments and the control (p<0.05). The cholesterol content of the control was lower than all treated samples, but the myofibrillar protein contents of all treated samples were higher than the control (p<0.05). The cooking loss of T2 was lower than the control and the other two treatments (p<0.05). The $L^*,\;a^*\;and\;b^*$ values of all treated samples were higher than those of the control during freezing storage (p<0.05). The W value of T3 at 1.5 and 3 months of freezing storage was higher than the control and T1 (p<0.05). The myoglobin and met-Mb contents of the control were similar to all treated samples, and the met-Mb content of the control and all treated samples increased with storage time (p<0.05). Immediately after freezing, the hardness of the control was higher than all treated samples, however it was lower after 1.5 and 3 months of frozen storage (p<0.05). The cohesiveness and gumminess of the control were higher than all treated samples immediately after freezing, however the values for T3 were higher than those of the control and the other two treatments during frozen storage for 1.5 and 3 months (p<0.05).

• Korean Journal of Environmental Biology
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• v.23 no.3 s.59
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• pp.293-303
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• 2005

Japanese medaka, Oryzias latipes is widely distributed in the North East Asia including Korea, Japan and east China, and commonly used for freshwater toxicity tests and cytotoxicological studies worldwide. In this study, a series of experiments were conducted to identify the potential of the fish as a standard test species for saltwater toxicity evaluation such as marine receiving waters, ocean-dumped materials and sediment pore waters etc. Hatching, growth and mortality rates of the fish were estimated with the wide ranges of salinity from freshwater to seawater (35 psu). Direct exposure of the fertilized eggs in freshwater to the wide ranges of salinity (from 0 to 35 psu) without pre- acclimation to the saltwater revealed no significant differences in hatching rates by salinities (p =0.24). On the other hand, medaka larvae hatched in freshwater and exposed to saltwater directly showed high mortality at > 25 psu treatment groups (p < 0.0001). However, there was no significant difference in mortality of medaka larvae hatched in 13.8 and 14.2 psu at the wide ranges of salinities ($0\~35$ psu). Growth rates of medaka larvae hatched in the above two salinities showed no differences in body length either from 0 to 35 psu treatment groups (p =0.64 for 13.8 psu group and p=0.32 for 14.2 psu group). The number of gill chloride cell in medaka larvae sharply increased when the larvae were exposed to high salinity. Reference tests with zinc chloride revealed 96h $LC_{50}=8.84(7.19\~10.87)mg\;L^{-1}$ using 7~10 day old medaka larvae. These were comparable or better sensitivity in comparison with the other standard test species such as North American sheepshead minnow Cyprinodon variegatus. Based on the results of these experiments, hatching rates and larvalmortality of medaka must be good toxicity parameters for seawater bioassay and the species seems to be a good standard species for both the freshwater and seawater toxicity test.

• Journal of Marine Bioscience and Biotechnology
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• v.7 no.1
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• pp.1-10
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• 2015

Bio diesel has advantages to reduce GHG(Greenhouse Gas) compare with the fossil fuel by using oil comes from plant/animal sources and even waste such as used cook oil. The diversity of energy feeds brings the positive effects to secure the national energy mix. In this circumstance, micro-algae is one of the prospective source, though some technical barriers. We analyzed the bio diesel which was derived from Dunaliella tertiolecta LB999 through the BD100 quality specifications designated by the law. From that result, it is revealed that the oxidation stability is one of the properties to be improved. In order to find the reason for low oxidation stability, we analyzed the oxidation tendency of each FAME components through some methods(EN 14111, EN14112, EN16091). In this study, we could find the higher double bond FAME portion, the more oxidative property(C18:1${\ll}C18:3$) in bio diesel and main unsaturated FAME group is acted as the key component deciding the bio diesel's oxidation stability. It is proved experimentally that C18:3 FAME are oxidized easily under the modified accelerated oxidation test. We also figure out low molecular weight hydrocarbon and FAME were founded as a result of thermal degradation. Some alcohol and aldehydes were also made by FAME oxidation. In conclusion, it is necessary to find the way to improve the micro-algal bio diesel's oxidation stability.

• Korean Journal of Microbiology
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• v.49 no.1
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• pp.38-45
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• 2013

In this study, euryhaline marine microorganism, Bacillus sp. strain EBW4 isolated from polychaete (Perinereis aibuhitensis) of Suncheon Bay was physiologically, biochemically and genetically characterized. Based on 16S rRNA sequence, EBW14 was found to share 98.25% similarity with Bacillus hemicentroti $JSM076093^T$, 97.96% similarity with Bacillus hwajinponensis SW-$72^T$ and 96.28% similarity with B. algicoa $KMM3737^T$, respectively. The temperature range for the growth of strain EBW4 was $4-40^{\circ}C$, NaCl concentration range 0-17% and pH range pH 5-9, revealing that EBW4 was euryhaline bacterium. Major fatty acids in strain EBW4 were composed of anteiso $C_{15:0}$ (48.2%), iso $C_{16:0}$ (12.1%), anteiso $C_{17:0}$ (11.6%) and iso $C_{14:0}$ (9.4%). EBW4 was found to have DNase, amylase, protease and lipase for the degradation of macromolecules such as DNA, carbohydrates, proteins, lipids, etc. The enzyme activities of alkaline phosphatase, esterase (C4), leucine arylamidase and ${\alpha}$-chymotrypsin were also found in strain EBW4. Analysis of the biodegradation ability of EBW4 for organic hydrocarbons under different salinity conditions using synthetic water waste revealed that EBW4 exhibited the ability to degrade organic hydrocarbons very quickly, suggesting strain EBW4 may be a good candidate for the application to various industries.

• Microbiology and Biotechnology Letters
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• v.45 no.3
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• pp.226-235
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• 2017

Carotenoids such as phytoene, lycopene, and ${\beta}-carotene$ are used as food colorants, animal feed supplements, and for human nutrition and cosmetic purposes. Previously, we reported the isolation of a novel marine bacterium, Kocuria gwangalliensis, which produces a pink-orange pigment. Phytoene desaturase (CrtI), encoded by the gene crtI, catalyzes lycopene formation from phytoene and is an essential enzyme in the early steps of carotenoid biosynthesis. CrtI is one of the key enzymes regulating carotenoid biosynthesis and has been implicated as a rate-limiting enzyme of the pathway in various carotenoid synthesizing organisms. Here, we report the cloning of the crtI gene responsible for lycopene biosynthesis from K. gwangalliensis. The gene consisted of 1,584 bases encoding 527 amino acid residues. The nucleotide sequence of the crtI gene was compared with that of other species, including Kocuria rhizophila and Myxococcus xanthus, and was found to be well conserved during evolution. An expression plasmid containing the crtI gene was constructed (pCcrt1), and Escherichia coli cells were transformed with this plasmid to produce a recombinant protein of approximately 57 kDa, corresponding to the molecular weight of phytoene desaturase. Lycopene biosynthesis was confirmed when the plasmid pCcrtI was co-transformed into E. coli containing the plasmid pRScrtEB carrying the crtE and crtB genes required for lycopene biosynthesis. The results from this study will provide valuable information on the primary structure of K. gwangalliensis CrtI at the molecular level.

• Animal Systematics, Evolution and Diversity
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• v.21 no.2
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• pp.233-241
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• 2005

Two new marine sponges of family Tedaniidae, Tedania (Tedon iu) songakensis n. sp. and Tedania (Tedonia) sasuensis n. sp. were collected from Jeju Island and Chuja Island, Korea between 2004 and 2005. T. (T.) songakensis n. sp. is similar to T (T.) purpurescen Bergquist and Fromont, 1988 based on its type of spicules, but is distinguished from growth form and size of small onychaetes. The growth form of this species is massive, and is compared with thin encrusting of Tedania (T.) purpurescen. The onychaetes of the new species is twice as long as that of T. (T.) purpurescen. T. (T.) sasuensis n. sp. is closely related to T. (T.) connectens (Bronsted, 1924) in type of spicules. However, it is different in size of onychaetes and growth form. The large onychaetes of new species is larger than that of T (T.) connectens. The small onychaetes of new species is smaller than that of T. (T.) connectens. The growth form is massive in new species, but thick encrustins in T.(T.) connectens. And T. (T.) songakensis n. sp. is similar to T. (T.) sasuensis n. sp. in growth form. However, the former is widely different from the latter in shape, color and size of all spicules.

• Journal of fish pathology
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• v.24 no.2
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• pp.121-129
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• 2011

Aquatic animal raised in hatcheries play an important role in supplying seedling to stock enhancement and seed quality, especially, seed health is the key factor for survival in the field after release and for stocking effectiveness. We have inspected the hatchery-reared seeds of 33 marine species and 12 freshwater species for legally designated diseases in stock enhancement program in 2010. Results showed that abalone was the most abundant as 20.0% in the marine species group and then sea cucumber (15.6%), olive flounder (8.4%), rockfish (6.7%), black sea bream (6.3%) and swimming crab (6.1%) were followed. Crucian carp was the most abundant as 19.4%, and then eel (11.8%), Korean bullhead (10.9%), mandarin fish (10.8%), melanian snail (8.4%), catfish (7.7%) were followed in the freshwater species group. The total number of inspection cases for eight pathogens in this study were 2,105 and disqualification cases were 30 by detection of aquatic animals pathogens such as koi herpesvirus (KHV), red sea bream iridovirus (RSIV), white spot syndrome virus (WSSV) or viral haemorrhagic septicemia virus (VHSV).

• Journal of Life Science
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• v.21 no.11
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• pp.1501-1510
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• 2011

In recent years novel potential pharmocological candidates have been looked for in animal, seaweed, sponge, fungi and marine bacteria resources. In this study, matrix metalloproteinases (MMPs) that play an important role in metastasis, arthritis, chronic inflammation and wrinkle formation were used as target enzymes to screen therapeutic agents. The inhibitory effects of several marine algae including green algae (5 species), red algae (18 species) and brown algae (4 species) methanolic extracts on MMPs were investigated in human dermal fibroblasts and human fibrosarcoma cell line (HT1080 cells) using gelatin zymography. In human dermal fibroblasts, the inhibition of MMP-2 was observed in Laurencia okamurae, Polysiphonia japonica, Grateloupia lanceolate and Sinkoraena lancifolia of red algae. In contrast, MMP-2 activation was enhanced in Enteromorpha compressa and E. linza of green algae, and Peltaronia bighamiae and Sargassum thunbergii of brown algae. In human fibrosarcoma cells, MMP-9 activation was decreased in the presence of S. thunbergii of brown algae, Polysiphonia japonica in red algae and E. compressa and E. linza of green algae. The interesting finding is that E. compressa and E. linza of green algae, and S. thunbergii of brown algae exhibited a positive effect on MMP-2 in normal cells, but a negative effect on MMP-9 in cancer cell lines. These results suggest that E. compressa and E. linza of green algae, and S. thunbergii of brown algae contain potential therapeutic ingredients for cancer treatment.