• Journal of Microbiology
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• v.39 no.4
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• pp.254-264
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• 2001

Sponges are host organisms for various symbiotic microorganisms such as archaea, bacteria, cyano-bacteria and microalgae. Sponges are also sources of a wide variety of useful natural products like cyto-toxins. antifouling agents, antibiotics, and anti-inflammatory and antiviral compounds, Symbiotic microorganisms is sponges can be sources of various natural products, because metabolites previously ascribed to sponges have recently been demonstrated to be biosynthesized by symbionts. If a symbiotic microorganisms from which some natural products are derived can be cultured, the microorganism could be used in a mass production of the bioactive comopounds. We summarize recent research on iso-lation and cultivation of sponge-symbiotic microorganisms and the symbiotic relationship.

• The Korean Journal of Malacology
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• v.23 no.1
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• pp.9-16
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• 2007

Data obtained from field observation revealed that the degree of shell bioerosion of the scallop, Patinopecten (Mizuhopecten) yessoensis, by endolithic organisms significantly higher on the muddy sand than on the sand. At the area studied, the polychaete worm, Polydora brevipalpa (=Polydora ciliata brevipalpa, Polydora ciliata Okuda, Not Johnston, Polydora variegata), which is common symbiotic species for the scallop made 95-100% of total scallop shell bioerosion at the area studied. The muddy bottom sediments enriched by organic matter create favourable conditions for development of microphytobenthos and bacteria, which are predominantly consumed by P. brevipalpa. Linear regressions for the degree of shell bioerosion on the scallop shell height, total wet weight and adductor muscle wet weight revealed negative relationships between them for the scallops inhabiting both sand and muddy sand. The influence of polychaetes on scallops is complex. They may be food competitors. Polychaete can directly affect the host through their boreholes. Scallop expends energy for shell regeneration to prevent the polychaete penetration into its interior cavity. It was found that the degree of shell bioerosion increased considerably with scallop age.

• Journal of Applied Biological Chemistry
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• v.49 no.1
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• pp.21-23
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• 2006

As part of a program to discover bioactive natural products from marine organisms, two new enantiomers, ent-3,6-Epidioxy-4,6,8,10-tetraethyltetradeca-7,11-dienoic acid and ent-[3,5-Diethyl-5-(2-ethyl-hex-3-enyl)-5H-furan-2-ylidene]-acetic acid methyl ether, were isolated from a sponge Plakortis sp. These compounds showed strong in vitro antiproliferative effects on promastigotes of Leishmania mexicania, flagellate protozoan that causes leishmaniasis. Structures were assumed by interpretation of NMR spectroscopic data and optical rotation. Both compounds exhibited significant antileishmanial activities in vitro with $IC_{50}$ of 1.0-23.0 ${\mu}g/ml$.

• YAKHAK HOEJI
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• v.28 no.1
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• pp.11-16
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• 1984

As main index of petroleum pollution in the marine organisms n-, iso-paraffins were purified with clean-up method and measured by FID-GC. Ten species of fishes from the near seas of Korea were employed for the study. n-Heptadecane was detected in most fishes. n-Hexadecane and n-octadecane of n-paraffins were highly accumulated in four species of fishes(Seriola quinqueradiata, Sardinia melamosticta, Clupanodon punctatus and Stromateoids argentus), also n-tetradecane and n-hexadecane accumulated in Cololadis saira. Remarkable peak pattern of n-paraffins was not observed in other fishes. Pristane of iso-paraffins was detected in four species of fishes (Sardinia melamosticta, Clupanodon punctatus, Stromateoides orgentus and Cololadis saira).

• Korean Journal of Environmental Biology
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• v.39 no.2
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• pp.236-244
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• 2021

Unarmored dinoflagellates, in the family Kareniaceae, include harmful or toxic bloom-forming species, which are associated with massive fish kills and mortalities of marine organisms worldwide. The occurrence and distribution of the toxigenic species in the family Kareniaceae were investigated in the brackish and coastal waters of Korea between July 2018 and October 2020. During the survey, we collected seven newly recorded species; Karenia papilionacea, Karlodinium digitatum, Karl. veneficum, Karl. zhouanum, Takayama acrotrocha, T. helix, and T. tasmanica. A total of fifteen strains of the seven taxa were successfully established as clonal cultures and examined using LM, SEM, and molecular phylogeny inferred from LSU rDNA sequences. Herein, we present the taxonomic information, morphological features, and molecular phylogenetic positions of the unrecorded dinoflagellate species collected from Korean coastal waters.

• Advances in nano research
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• v.14 no.3
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• pp.273-284
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• 2023

Combating the worldwide environmental threat of plastic waste pollution has become a priority. Plastic pollution has the potential to impact land, rivers, and seas, since many marine and terrestrial organisms have perished as a result of plastic's non-biodegradability and soil dangers. For this consumption, it seems required to manufacture and use new renewable resources. Renewable materials for diverse applications have been created utilizing nanotechnology, which may replace conventional materials for children's activities and sports equipment. This study investigates and suggests that nanotechnology-based materials be replaced with conventional materials to save the environment in manufacturing equipment for children's physical activities. On the basis of the mechanical sciences, a stability study of the bending behavior of small-scale structures will be performed for the various recommended materials.

• Journal of the Institute of Convergence Signal Processing
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• v.16 no.3
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• pp.108-114
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• 2015

Ballast water is carried by ships to ensure stability, trim and structural integrity. When a ship loads cargo, the ballast water is discharged. When foreign marine microorganisms are introduced into new marine environments, they pose a threat to the local marine ecological system. UV system is commonly used for the disinfection of waste and surface water. This method would not be as efficient because some species do survive to form viable populations, much of the sediment and organisms at the bottom of tanks, and may become serious pests. In this paper, we designed and implemented ballast water treatment system using fuzzy PID controller to prevent lamp damage, and to reduce the formation of the viable populations. The experiments were conducted with ballast water treatment system using fuzzy PID controller with short time exposure to the temperature above $40^{\circ}C$. This system was shown to be effective by significantly reducing bacterial population and lamp life extension through appropriate temperature of ballast water.

• Journal of Environmental Science International
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• v.23 no.3
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• pp.483-492
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• 2014

DNA damage such as genotoxicity was identified with comet assay, which blood cell of a marine parrot fish (Oplegnathus fasciatus) was exposed to an acidified seawater, lowered pH gradient making of $CO_2$ gas. The gradient of pH were 8.22, 8.03, 7.81, 7.55 with control as HBSS solution with pH 7.4. DNA tail moment of fish blood cell was $0.548{\pm}0.071$ exposed seawater of pH 8.22 condition, on the other hand, DNA tail moment $1.601{\pm}0.197$ exposed acidified seawater of pH 7.55 lowest condition. The approximate difference with level of DNA damage was 2.9 times between highest and lowest of pH. DNA damage with decreasing pH was significantly increased with DNA tail moment on blood cell of marine fish (ANOVA, p < 0.001). Ocean acidification, especially inducing the leakage of sequestered $CO_2$ in geological structure is a consequence from the burning of fossil fuels, and long term effects on marine habitats and organisms are not fully investigated. The physiological effects on adult fish species are even less known. This result shown that the potential of dissolved $CO_2$ in seawater was revealed to induce the toxic effect on genotoxicity such as DNA breakage.

• Journal of the Korean Society of Marine Environment & Safety
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• v.16 no.4
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• pp.361-367
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• 2010

The use of antifouling(AF) paints is the effective method for the protection of underwater structures from the development of marine fouling organisms. The ban on harmful substances in antifouling paints requires the development of new antifouling strategies although Tributyitin (TBT) compound had been used extensively as an active ingredient Alternatives should be as effective as conventional paints but have lower toxicity. In the present study, a TBT-free self-polishing (Cu SPC) AF paint containing $Cu_2O$, a Cu free SPC AF paint, and a Foul-release silicone AF paint, which were commercially available, were examined to investigate environmental erects of leakage waters employing Sebastes shlegeli and Artemia. Survival rates were inversely proportional to the concentration of leakage waters from AF paints and the acute toxicity of SPC AF paints was relatively higher than that of foul release AF paints.

• Journal of the Korean Society for Marine Environment & Energy
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• v.11 no.4
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• pp.214-220
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• 2008

The Ballast Water Management Convention provides that ballast water treatment systems which make use of active substances shall be approved from IMO according to the procedure developed by the IMO. The Convention described that active substance means a substance or organism, including a virus or a fungus, that has a general or specific action on or against harmful aquatic organisms and pathogens. The Marine Environment Protection Committee of IMO gave basic approval to 13 ballast water management systems and final approval to 4 systems until October 2008. This paper considered the matter of procedure and documents of the basic and final approval based on the "Procedure for approval of ballast water management systems that make use of Active Substances (G9)" and "The Methodology for information gathering and the conduct of work of the GESAMP-BWWG" and summarized the specifications of the treatment systems which was granted the basic or final approval from IMO and raised several points.