• Food Science and Industry
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• v.51 no.2
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• pp.157-164
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• 2018

Recently demand for safer and healthier food has augmented with advancements in health conditions. Food ingredients with yet to be known safety and functionality, are being investigated for their safety or detrimental effects. The Ministry of Food and Drug Safety has introduced "health functional food" by the "Health Functional Food Act" to evaluate bio-functional and safety properties of raw materials using standard methods including in-vitro and in-vivo testing before human consumption. Despite recent growth in net worth of domestic functional food market, most of the raw materials are not from local Korean industries with own research and development, and mostly terrestrial not marine resources. Geographically, Korea has access to diverse marine bio-resources that need to be managed and utilized sustainably. Recently, diverse novel physiologically active substances have been reported from marine organisms. Hence, the development of functional foods from marine bio-resources is considered as an inevitably important task.

• Journal of Marine Life Science
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• v.7 no.2
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• pp.113-120
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• 2022

Despite concerns about the significant toxicity of copper pyrithione (CuPT) at environmental concentrations, effects of CuPT on benthic organisms have received little attention. Here, we analyzed the detrimental effects of CuPT at sublethal concentrations (1/50, 1/20, and 1/10 of the 96 h-LC50 value) for 14 days in the marine polychaete Perinereis aibuhitensis. Reduced burrowing activity and significantly decreased the acetylcholinesterase activity in response to relatively high concentrations of CuPT were identified as CuPT-triggered cholinergic inhibition. The lipid peroxidation marker, malondialdehyde levels were dose-dependently increased, whereas intracellular glutathione was depleted by relatively high concentrations. In the CuPT-treated polychaete, significant fluctuations in the enzymatic activities of the antioxidant defense system (catalase, superoxide dismutase, glutathione reductase, and glutathione peroxidase) were observed with significantly modulated glutathione 𝘚-transferase activity. These results indicate that even sublethal levels of CuPT would have detrimental effects on the health status of the marine polychaete.

• Journal of Marine Bioscience and Biotechnology
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• v.12 no.1
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• pp.50-58
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• 2020

Sphacelaria is a filamentous brown algal genus that can be epibiotic on macroalgae, marine plants, and sea turtles. Its important role in benthic ecosystems, exposure to different stressors (e.g., grazing), and use as a model organism make Sphacelaria ideal for assessing physiological responses of organisms to environmental inputs. Single-cell RNA sequencing is a powerful new probe for understanding environmental responses of organisms at the molecular (transcriptome) level, capable of delineating gene regulation in different cell types. In the case of plants, this technique requires protoplasts ("naked" plant cells). The existing protoplast isolation protocols for Sphacelaria use non-commercial enzymes and are low-yielding. This study is the first to report the production of protoplasts from Sphacelaria fusca (Hudson) S.F. Gray, using a combination of commercial enzymes, chelation, and osmolarity treatment. A simple combination of commercial enzymes (cellulase Onozuka RS, alginate lyase, and driselase) with chelation pretreatment and an increased osmolarity (2512 mOsm/L H₂O) gave a protoplast yield of 15.08 ± 5.31 × 10⁴ protoplasts/g fresh weight, with all the Sphacelaria cell types represented. Driselase had no crucial effect on the protoplast isolation. However, the increased osmolarity had a highly significant and positive effect on the protoplast isolation, and chelation pretreatment was essential for optimal protoplast yield. The protocol represents a significant step forward for studies on Sphacelaria by efficiently generating protoplasts suitable for cellular studies, including single-cell RNA sequencing and expression profiling.

• Food Science and Biotechnology
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• v.18 no.4
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• pp.872-877
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• 2009

By-products of marine organisms including salmon, skate, flatfish, and yellow goosefish were investigated to search for new source of chondroitin sulfate (CS). Agarose gel electrophoresis with chondroitinase depolymerization showed that purified chondroitin sulfate did not contain any other glycosaminoglycans. 1H-nuclear magnetic resonance (NMR) spectra were acquired to confirm the structure and purity. The average molecular weight ranging from 22 to 64 kDa was determined by high performance size exclusion chromatography. Disaccharide compositions and purities were determined by strong anion exchange-high performance liquid chromatography (SAX-HPLC) after chondroitinase ABC depolymerization. SAX-HPLC data exhibited that the purity was from $81.7{\pm}1.3$ to $114.2{\pm}2.5%$ and the yield was from 1.3 to 12.5%. All analytical results indicate that salmon cartilage, skate cartilage, and yellow goosefish bone could be promising sources of CS to substitute shark cartilage CS in commercial neutraceuticals.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.47 no.4
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• pp.431-434
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• 2014

Cytogenetic analysis was conducted to obtain basic information for chromosome manipulation of starry flounder Platichthys stellatus. Nuclear surface area and volume of erythrocyte were $7.60{\pm}0.93{\mu}m^2$ and $12.80{\pm}1.75{\mu}m^3$, respectively. The haploid DNA content of the species was 0.66 pg/haploid cell which correspond to 93% of olive flounder Paralichthys olivaceus. A karyotype analysis was also carried out with the species using conventional staining and Ag-NOR banding techniques. It was consisted of 48 acrocentric chromosomes and inter-sex or intra-individual polymorphism was not detected in all specimens analyzed. The NOR regions, appearing a terminal position of the short arm of the smallest acrocentric pairs.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.46 no.6
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• pp.901-906
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• 2013

We examined the availability of the lacZ gene (${\beta}$-galactosidase gene) as a reporter of foreign gene transfer in the cysts of Artemia franciscana (A. franciscana) to conduct a risk assessment of living genetically modified organisms (LMOs) in the marine ecosystem. The LacZ gene was transferred to decapsulated cysts by particle bombardment, and its insertion and expression were assessed by means of polymerase chain reaction (PCR) and X-gal staining. X-gal staining indicated lacZ expression in all A. franciscana examined (including the control group), which exhibited not only negative but also positive PCR amplification. Endogenous ${\beta}$-galactosidase is highly active in the whole body of A. franciscana during all stages of the life cycle. Thus, the lacZ gene is unsuitable as a reporter for foreign gene transfer in A. franciscana cysts, because it is difficult to discriminate between exogenous and endogenous ${\beta}$-galactosidase activity.

• Proceedings of the Korean Society of Marine Engineers Conference
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• 2006.06a
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• pp.273-274
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• 2006

The sea is origin of all lift, and 90% of the all living organisms are in the sea. The biosynthesis is very different. Many organisms are kept on a lower or developed to another evolutionary level than on shore. Our society is increasing demand and need for marine food and this food has to product at onshore or offshore fish farming sites. Ocean fish farms have a special operation properties such as a good quality water, net cage, sheltered locations and feeding system. The farming site is controlled and monitored for fish welfare as ammonia($NH_3$), temperature, the speed of a running fluid. Specially, the fish farm is seriously influenced by ammonia. In this paper, $NH_3$ monitoring system for ocean fish farm is researched for the suitable fish farming sites, and test equipment is designed for achieving practical data. The equipment wit monitoring algorithm is expected to the useful system for ocean fish farm.

• Journal of Marine Bioscience and Biotechnology
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• v.10 no.2
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• pp.34-43
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• 2018

Silicon has become of increasing importance as the basic element of many high-technology products. Its synthesis is very difficult requiring high temperature solid-state reactions (> $1000^{\circ}C$) or lower temperature methods ($100-200^{\circ}C$) involving hydrothermal and solvothermal reactions under extreme pH conditions. In nature, on the other hand, a wide range of living organisms have collectively evolved the means of biosilicification at the astounding rate of gigatons/year. This is impressive because biosilicification in these organisms occurs under mild physiological conditions. Marine sponges possess the ability to sequester soluble silicon sources from their environments and assemble them into intricate 3D architecture. The advent of molecular biology has recently made it possible to glean molecular information about biosilicification from these systems and it turned out that enzyme silicatein is the core of biosilicification. In this review, biosilicification regulated by silicatein and its mechanism are described. Also, production of silicatein through recombinant technology and several applications of recombinant silicatein are described including immobilization of silicatein, formation of Au or Ag nanoparticles on nanowires, nanolithography approaches, core-shell materials, encapsulation, bone replacement materials, and microstructured optical fibers.

• Journal of Environmental Impact Assessment
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• v.26 no.3
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• pp.207-216
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• 2017

Several bioassays have been performed for assessment of the impact of polluted sediments. The direct exposure method using sediments is limited by difficulty controlling feeding and its effects on organisms. Furthermore, only macro-organisms and benthic organisms are used. To evaluate the potential application of sediment elutriate as a complementary strategy for impact assessment, copepods, small organisms with a short life cycle, were exposed to sediment elutriates, and several end-points were measured. As a result, sediment elutriates prepared from polluted sites caused growth retardation in marine copepods. In terms of molecular biomarkers, antioxidant-related and chaperone protein gene expression levels were increased in a dose- and time-dependent manner. Thus, we suggest that sediment elutriate tests can provide an effective alternative for toxicity assessment using whole sediment samples. Further studies are required to obtain sufficient data for future applications.

• Journal of Aquaculture
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• v.10 no.1
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• pp.9-15
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• 1997

The pathogenic organisms occurred in cultured marine fishes in Kamak Bay were investigated from March to November in 1993. The samples were collected at 7 sampling stations once a month. Nine species of pathogenic organisms (Vibrio sp., Edwardsiella sp., Flexibacter sp., Streptococcus sp., Micrococcus sp., Caligus sp., Trichodina sp., Lymphocystis and Staphylococcus sp.) were identified as pathogenic organisms from four different species of fish (Sebastes schlegeli, Paralichthys olivaceus, lateolabrax japonicus and Pagrus major) collected in the study areas. Most of pathogenic organisms were found at over 20^{\circ}C$ of sea water temperature from June to October in 1993. On the test of drug sensitivity, Vibrio sp. (KS-9303) was sensitive to oxytetracycline and chloramphenicol ; Edwardsiella sp. (KP-9315) to oxytetracycline ; Flexibacter sp. (KP-9318) to oxytetracycline, chloramphenicol and oxolinic acid ; Streptococcus sp. (KP-9319) to erythromycin, chlorampheicol and oxytetracycline. However, all these 4 isolated bacteria were resistant to ampicilin, steptomycin, sulfamethoxazole and nitrofurazone.