• Korean Journal of Fisheries and Aquatic Sciences
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• v.54 no.6
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• pp.1007-1016
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• 2021

This study examined the characteristics and seasonal distribution patterns of subtidal marine algal communities along the east coast of Korea, from 2016 to 2017, and recorded the coverage ratio (%) by the algal type. During the study period, 134 marine algae species (16 green, 29 brown, and 89 red) were identified at the survey sites. The maximum number of species was observed at the Nagok site (70 species), and the minimum at the Gisamoon site (50 species). The total average biomass (dry weight) during the survey period was 66.22 g/m², including green algae (2.19 g/m²), brown algae (38.10 g/m²), and red algae (25.94 g/m²). The dominant seaweeds in the vertical distribution based on coverage rates (%) were Sargassum yezoense and Dictyopteris divaricata at the upper, Symphyocladia latiuscula and Undaria pinnatifida at the middle, and Agarum clathratum subsp. yakishiriense and Plocamium telfairiae at the lower sections of the distribution. Richness, evenness, and diversity index, calculated based on the biomass of the abundant species, were estimated to be 6.36, 0.55, and 1.98, respectively, over the entire sea area. Based on the evaluation of the environmental states using community indices, the ecological evaluation index (EEI-c) of subtidal marine algal communities along the east coast of Korea was marked as 'good-moderate'.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.40 no.5
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• pp.323-331
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• 2007

Barren ground is an abnormal phenomenon in coastal ecosystems where seaweeds are destroyed and largely replaced by coralline algae containing calcium carbonate components. To restore the seaweed forest, we attempted reconstruction in an area of Samcheok, Korea, where barrenness is extensive. We developed two methods of seaforest construction underwater longline and seed transplantation for the brown seaweed Laminaria japonica, a fast-growing edible seaweed. The blade length of L. japonica attached to an underwater long line was $93.9{\pm}38.2cm$ and blade weight $7.6{\pm}2.1g$ in February 2004. Seaweed size declined after August 2004. A Similar pattern was observed using the transplantation method with maxima of $179.3{\pm}40.3cm\;and\;14.9{\pm}3.2g$ for blade length and weight, respectively in July 2004. The transplanted seaweeds matured in October as did a wild population. These results indicate that transplanted seaweed acclimate to new environments.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.21 no.1
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• pp.44-47
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• 2016

Real-time PCR was applied to early warning of red tide. For early warning of red tide at $10cells\;mL^{-1}$, Cochlodinium polykrikoides specific real-time PCR was used as a complement of microscopy that has a lower detection sensitivity. C. polykrikoides appeared extensively in Tongyeong, Namhae waters at low densities in the end of June, and early warning of C. polyrkrikoides blooms was issued on 2 August 2015.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.36 no.4
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• pp.365-371
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• 2003

The reared fries of black sea bream, Acanthopagrus schlegeli were released in Gamak Bay and initial adaptation to the environment was evaluated. Thirty thousand fries were marked with magnetic tag, released and recaptured and its stomach content were analysed; the neighboring zooplankton, beuthic algae and other young fishes were investigated. The fries were released on July 30, 2001 in summer season. Water temperature of surface and bottom were $24^{\circ}C\;and\;21^{\circ}C,$ respectively. $Chlorophyll\;\alpha$ content was 4.5 ${\mu}g/L$ with high primary production. Salinity was $32.0-32.5\%_{\circ}.$ Water depth of releasing site was about 30 m. The sea jungle was formed at the first point of releasing and it kept the fries for about 3 days in the bay with plenty of food organisms within 5 m depth. Stomach analysis of the fries revealed that real feeding started from the 15 days after releasing and full feeding took place after the tenth day.

• KSBB Journal
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• v.26 no.6
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• pp.538-542
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• 2011

The research was purposed production of oligosaccharide from alginate hydrolysis the main composition in cell walls of sea weed. We was isolated 252 strains from sea water and mud flat, the highest alginate lyase activity was selected, and identified as Sanguibacter keddieii NC9 by 16S rDNA sequence analysis. In this study was select the sodium alginate concentration, pH, temperature for the production of alginate lyase activity. Alginate lyase activity was confirmed from plate assay with 10% cetylpyridinium chloride. The optimum culture conditions for the production of alginate lyase were sodium alginate 10 g/L, peptone 5 g/L, $40^{\circ}C$, pH 9 and 36 hours incubation time. Sanguibacter keddieii NC9, its alginate lyase would be useful for the production of bioenergy and biofunctional oligosaccharides from sea weed.

• Journal of Marine Bioscience and Biotechnology
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• v.15 no.1
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• pp.24-32
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• 2023

The Laminaria japonica Aresch (Sea tangle) belongs to the brown algae and has a long history as a food material in Asia, including Korea. Recent studies have found that the fermented Sea tangle extract (FST) inhibited the differentiation of osteoclasts and protected osteoblasts from oxidative damage. This study aims to explore the possibility that FST can induce the differentiation of osteoblasts and identify the responsible mechanism. According to our results, FST induced differentiation into osteogenic cells in the presence of osteoblastic MC3T3-E1 cells under non-toxic conditions.. This finding was confirmed by phalloidin staining, increased alkaline phosphatase activity, and calcium deposition. Additionally, it was found that this process was achieved by increasing the expression of key factors involved in osteoblast differentiation, such as runt-related transcription factor-2, osterix, β-catenin, and bone morphogenetic protein-2. Moreover, FST increased autophagy, which may contribute to the maintenance of the bone formation homeostasis, and is associated with the activation of the phosphatidylinositol 3-kinase/Akt and mitogen-activated protein kinase signaling pathways. Although further research about the bioactive substances contained in FST and the tests of their efficacy are required, the results of this study indicate that FST has incredible applicability as a functional material for maintaining the bone homeostasis.

• Journal of Life Science
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• v.16 no.6
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• pp.1044-1051
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• 2006

The barren ground is an abnormal phenomenon of coastal ecosystem in which seaweeds, are destroyed and mostly replaced by the coralline algae containing the calcium carbonate components. To restore the seaweed forest, We have exerted an effort in the local areas, Samchuck, Korea, where barren phenomena are profound. Two methods of seaweed forest construction developed in the present study are underwater longline and seed transplantation for the brown seaweed Costaria costata, a fast growing edible seaweed. The sizes of C. costata attached on the underwater longline were $96.7{\pm}2.2mm$ of blade length and $83.6{\pm}7.7g$ of blade weight in April. Thereafter the sizes declined from May. Similar pattern was obtained from in the transplantation method with maxima of $90.4{\pm}15.8mm$ and $70.1{\pm}31.7g$ for blade length and weight, respectively in April. It appeared totality maturation from two methods in May. This maturation time is the same like that of wild C. costata.

• The Korean Journal of Malacology
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• v.25 no.2
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• pp.105-112
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• 2009

We investigated the degree of obesity, histological development stages of gonads and sexual maturation induction rates of comb pen shell, Atrina pectinata, per the type of micro-algae supplied. Terms of maturation by singular or mixed supply of microalgae, it was found that maturation of the female was the quickest at 60.0% by the Tetraselmis tetrathele (Tet). experiment group followed by 57.1% by the Chlorella ellipsoidea (Chl). experiment group and 16.7% by the Phaeodactylum tricornutum (Pha). experiment group. However, there were no significant differences between Tet. experiment group and Chl. experiment group. As for the male, maturation was the quickest at 60.0% by the Tet. experiment group followed by 16.7% by the Chl. experiment group and 14.3% by the Pha. experiment group. In light of these results, Tet. is concluded to be a very useful feed organism in breeding the mother comb pen shells. Upon completion of the experiment, the sexual maturation induction rate for the female was found to be the highest at 82.0% in the Tet. experiment group followed by 72.0% by the Chl. experiment group, 64.0% by the Pha. experiment group and 58.0% by the mixed micro-algae experiment group. During the period of experiment, the survival rate was the highest at 94.4% by the mixed micro-algae experiment group followed by 90.0% by the Pha. experiment group, 83.1% by the Tet. experiment group and 78.8% by the Chl. experiment group.

• KSBB Journal
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• v.24 no.5
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• pp.483-488
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• 2009

The Brown-algae polysaccharide consisting of alginate and laminaran is usable as high bio-ethanol production if hydrolyzed to monomer unit. The objective of this study is to produce bio-ethanol from brown-algae using enzymatic saccharification. Bio-ethanol was produced by Saccharomyces cerevisiae KCCM 1129 and Pachysolen tannophilus KCTC 7937 strains. The substrate used Laminaria japonica, Sargassum fulvellum and Hizikia fusiformis. We isolated a new alginate lyase and laminaran lyase producing microorganism for hydrolysis of brown-algae from southern sea of Gijang. The reducing sugar was obtained 1.90 g/L from Laminarin japonica 20 g/L that used enzyme from Bacterium antarctica. In pretreatment of the most suitable brown-algae for ethanol production, ethanol concentration of 0.93 g/L and yield of 4.65% were obtained in condition of Laminaria japonica in medium.

• Proceedings of the Korean Journal of Food and Nutrition Conference
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• 2001.12a
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• pp.125-125
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• 2001

Total lipid contents were 0.58∼3.00% in 9 kinds of brown algaes, 0.47∼2.16% in 5 kinds of red algaes and 0.55∼2.99% in 2 kind of green algeas, respectively. Fatty acid compositions of the algaes were determined by gas liquid chromatography. Total polyenes and n-3 polyenes of linoleic acid(18:3), stearidonic acid(18:4), eicosapentaenoic acid(20:5) and docosahexaenoic acid(22:6) were 3.88∼57.57% and 1.46∼25.67% in the brown algaes, 5.30∼39.75% and 1.17∼21.91% in the red algaes, and 7.76∼19.27% and 3.67%∼10.61% in the green algaes, respectirely. The fatty acid contents and compositions of total polyenes and n-3 polyenes were vary different in the algae groups and sepecies.