• Fisheries and Aquatic Sciences
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• 제26권3호
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• pp.181-187
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• 2023

The control of intestinal α-amylase and α-glucosidase is an effective therapeutic strategy for prevention of post-prandial hyperglycemia associated with diabetes mellitus. The objective of this study was to evaluate the anti-diabetes activities of Korean edible seaweed against α-amylase and α-glucosidase, two carbolytic enzymes involved in serum glucose regulation. Of the 41 species initially screened, Cladophora wrightiana var. minor, Eisenia bicyclis, Ecklonia cava, Ishige foliacea, and Ishige okamurae exhibited the strongest inhibitory activities from brown seaweeds. Asparagopsis taxiformis showed the strongest inhibitory effects from red seaweeds. The results of this study suggest that the crude brown seaweed extracts (C. wrightiana var. minor, E. bicyclis, E. cava, I. foliacea, and I. okamurae) and crude red seaweed extracts (A. taxiformis) may have beneficial effects suppressing the rise in postprandial hyperglycemia through the inhibition of α-amylase and α-glucosidase.

• Fisheries and Aquatic Sciences
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• 제12권2호
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• pp.130-137
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• 2009

Temporal variations of seaweed biomass and coverage were seasonally examined at Ongdo in the Yellow Sea, Korea from August 2006 to April 2008. Average seaweed biomass was 245.79 g/$m^2$ in wet weight and coverage was 16.49% with seasonal variations from 13.97% in spring to 18.55% in autumn. Seaweeds were distributed across the shore gradient from the high intertidal to 10m depth in the subtidal zone. Biomass was always higher in the subtidal zone (310.24 g/$m^2$) than in the intertidal zone (181.35 g/$m^2$). Of total seaweed biomass, 76.52% (first year) and 80.32% (second year) occurred from the low intertidal zone, down to depth of 1 to 5m. Gelidium amansii had the highest importance value and biomass, and sub dominant species were Chondrus ocellatus and Chondria crassicaulis. Coarsely-branched seaweeds comprised the highest proportion of biomass (214.84 g/$m^2$, or 87.41% of the total biomss). Seasonal variations in algal biomass were largely explained by fluctuations in the biomass of coarsely-branched and thick-leathery forms. In conclusion, seaweed biomass of Ongdo shore was very low because of perennial G. amansii showing low biomass as compared to kelp or Sargassum spp. However, these results indicate Ongdo is good place to grow seaweeds because coarsely-branched form seaweeds including G. amansii are dominant at unpolluted and clean environment.

• 한국수산과학회지
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• 제51권4호
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• pp.369-375
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• 2018

This study investigated the effects of selected seaweeds on rice koji preparation (rice inoculated with Aspergillus luchuensis) and enzyme activity. Four types of rice koji were prepared using one of three seaweeds (0.5% laver, 0.5% kelp and 0.5% green laver) or a control for 72 h. The changes in the moisture content, water activity, pH, total mold cell count, amylase and protease activities were measured. During preparation, there was no significant difference in the moisture content among the four kojis, whereas the pH in the kojis made with either laver or green laver decreased rapidly compared with the control (P<0.05). This seemed to result from the seaweeds promoting the growth of mold cells. In terms of the activities of both amylase and protease, the koji with laver was superior. Subsequently, the amylase and protease activities of the koji made with laver were evaluated at various pHs (3 to 9), temperatures ($15-55^{\circ}C$) and NaCl concentrations (0-10%). The activities of both enzymes decreased notably at pH 9 and the protease activity decreased at temperatures above $45^{\circ}C$. Although the activities of both enzymes decreased at greater than 2.5% NaCl, activity was present at 10% NaCl.

• 한국수산과학회지
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• 제55권6호
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• pp.836-843
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• 2022

In the present study, exposure to heavy metals by consumption of edible seaweeds (green laver, laver, hijiki, sea tangle, and sea mustard) was assessed based on their concentrations of lead (Pb), cadmium (Cd), arsenic (As), and mercury (Hg). The mean of heavy metal concentrations were 0.006-0.023 mg/kg for Pb, 0.037-0.156 mg/kg for Cd, 1.117-15.928 mg/kg for As, and 0.008-0.021 mg/kg for Hg. In multivariate analysis, the correlations were high between Pb levels in sea mustard, Cb levels in laver, and As and Hg level in Hijiki. However, the estimated daily intake and target hazard quotient (THQ) of the heavy metals in edible seaweeds were below their approved limits suggesting no health risks associated with seaweed consumption by Koreans.

• 한국식품영양과학회지
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• 제34권9호
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• pp.1464-1470
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• 2005

우리나라 연안에서 수집한 김(33점), 미역(88점), 다시마(12점), 파래(43점)등 총 176점의 주요 식용 해조류에 대한 미량금속의 함량을 조사한 결과, 아연, 망간, 구리 순으로 우리 체내에서 없어서는 안되는 필수성분들의 함량이 높았으며, 다음으로 크롬, 니켈, 납, 카드뮴, 수은 순이었다. 김에서는 카드뮴과 아연이, 그리고 파래에서는 크롬, 니켈 및 납이 가장 높게 검출되었고, 다시마에서는 수은이 가장 높게 검출되는 경향을 나타내었다. 카드뮴과 아연의 농축계수는 김에서 각각 약 12,000 및 14,000으로 가장 높게 나타났으며 크롬과 납은 파래 에서 각각 약 23,000 및 약 2,500으로 가장 많이 농축되었다. 또한, 구리는 김과 파래에서 약 5,500으로 많이 농축되었다. 다시마에서는 망간과 납 사이에 다른 식용해조류와는 달리 특이적으로 높은 상관관계를 나타내었으며, 금속간의 상관관계도 같은 갈조류인 미역, 그리고 녹조류인 파래와 전혀 다른 경향을 나타내었다. 김, 미역, 파래에서는 니첼-망간, 니켈-크롬 및 망간-크롬간에는 높은 상관관계를 나타내어 다른 금속들과 뚜렷한 차이를 보였으며, 특히 크롬-니켈은 높은 상관관계를 나타내었다. 우리나라 국민의 식용해조류를 통한 수은의 1일 섭취량은 평균 $0.03{\mu}g$이었으며, 이는 PTWI($5{\mu}g/kg$ body weight/week)의 $0.07\%$ 수준이었다. 또한, 카드뮴의 1일 섭취량은 평균 $2.15{\mu}g$이었으며, 이는 PTWI(7${\mu}g/kg$ body weight/week)의 $3.57\%$ 수준이었다. 납의 1일 섭취량은 평균 $2.65{\mu}g$이었으며, 이는 PTWI($25{\mu}g/kg$ body weight/week)의 $1.20\%$ 수준이었다. 따라서 우리국민이 해조류를 통해 일주일에 섭취하는 수은, 납, 카드뮴등의 함량은 PTWI의 $0.07{\~}3.57\%$에 해당되며, 유해중금속 함량은 매우 안전한 수준인 것으로 판단된다. 우리나라 국민은 해조류 통한 구리, 아연, 망간, 크롬의 섭취량은 영양소 기준치의 각각 1.35, 0.89, 4.28, $9.18\%$ 수준이었다.

• 대한지역사회영양학회지
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• 제15권3호
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• pp.361-368
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• 2010

This study was carried out to investigate preference and purchase factors of seaweed in some regional residents of Korea. Subjects were residents (n = 1,218) whose residential area was divided into inland and coastal region and the survey was done during December 2007. Especially, purchase factors of seaweeds was conducted only in married females (n = 353). The subjects are composed of 46.5% male and 53.5% female. Regional distribution of subjects was found to be 16~17%, with highest ratio in the age bracket of 20~29 years old. Proportion of students, at 29.8%, was the highest ranking occupation of the subjects. Preference score of seaweeds by region was highest for laver followed by brown seaweed and sea tangle. In terms of preference by gender, female subjects displayed higher preference score for green laver (p < 0.01), seaweed fusiforme, brown seaweed, sea tangle (p < 0.001) than the male subjects. Considerations being made when purchasing seaweeds for each region were in the order of freshness, taste and nutrition. In comparing the inland and coastal region, scores of freshness, convenience, design and color for the coastal region was higher, displaying significant difference.

• 한국수산과학회지
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• 제29권6호
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• pp.770-778
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• 1996

A rapid and economical method of simultaneous extraction of DNA and RNA from seaweeds has been developed by the use of lithium chloride. Lithium chloride facilitates the softening of cell walls resulting in a decrease in both compressive and tensile modulus of elasticity. The DNA was characterized by high molecular weight larger than 27 kb and a relative lack of carbohydrate and protein contamination. The DNA and RNA extracted by the method from many seaweeds were of sufficient quality to be used as a template for per amplification with a plant intergenic gene primer set, for RAPD analysis with arbitrary primers, and for differential display with arbitrary primers in the morphologically distinct regions of the matured Porphyra thallus. The cDNA polymorphism indicated that the reproductive tissue types (male, female, patch) had a relatively high degree of similarity; the vegetative tissue types (dividing, non-dividing) also showed a similar pattern with respect to each other. Holdfast tissue had very low similarity with the other tissues, but appeared most similar to vegetative non-dividing tissue type.

• Nutrition Research and Practice
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• 제8권4호
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• pp.377-385
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• 2014

BACKGROUND/OBJECTIVES: Abundant consumption of seaweeds in the diet is epidemiologically linked to the reduction in risk of developing cancer. In larger cases, however, identification of particular seaweeds that are accountable for these effects is still lacking, hindering the recognition of competent dietary-based chemo preventive approaches. The aim of this research was to establish the antiproliferative potency and angiosuppressive mode of action of Stoechospermum marginatum seaweed methanolic extract using various experimental models. MATERIALS/METHODS: Among the 15 seaweeds screened for antiproliferative activity against Ehrlich ascites tumor (EAT) cell line, Stoechospermum marginatum extract (SME) was found to be the most promising. Therefore, it was further investigated for its anti-proliferative activity in-vitro against choriocarcinoma (BeWo) and non-transformed Human embryonic kidney (HEK 293) cells, and for its anti-migratory/tube formation activity against HUVEC cells in-vitro. Subsequently, the angiosuppressive activity of S. marginatum was established by inhibition of angiogenesis in in-vivo (peritoneal angiogenesis and chorioallantoic membrane assay) and ex-vivo (rat cornea assay) models. RESULTS: Most brown seaweed extracts inhibited the proliferation of EAT cells, while green and red seaweed extracts were much less effective. According to the results, SME selectively inhibited proliferation of BeWo cells in-vitro in a dose-dependent manner, but had a lesser effect on HEK 293 cells. SME also suppressed the migration and tube formation of HUVEC cells in-vitro. In addition, SME was able to suppress VEGF-induced angiogenesis in the chorio allantoic membrane, rat cornea, and tumor induced angiogenesis in the peritoneum of EAT bearing mice. A decrease in the microvessel density count and CD31 antigen staining of treated mice peritoneum provided further evidence of its angiosuppressive activity. CONCLUSIONS: Altogether, the data underline that VEGF mediated angiogenesis is the target for the angiosuppressive action of SME and could potentially be useful in cancer prevention or treatment involving stimulated angiogenesis.

• ALGAE
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• 제20권3호
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• pp.251-260
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• 2005

Antioxidative activities of Chlorophyta and Phaeophyta in Jeju Island were measured by superoxide anion ($O_2^{{\cdot}-}$), hydroxyl radical ($HO^{\cdot}$), hydrogen peroxide ($H_2O_2$) and DPPH free radical scavenging assays. Methanolic and aqueous extracts of the seaweeds were prepared at both temperatures, higher (70$^{\circ}C$) and room temperature (20$^{\circ}C$), and screened for the construction of an extract bank from seaweeds in Jeju Island. A variety of extracts showed positive effect against reactive oxygen species (ROS). Especially, Sargassum thunbergii methanolic extract at 70$^{\circ}C$ (70ME, 97.41%), S. fulvellum methanolic extract at 20$^{\circ}C$ (20ME, 84.66%), Codium fragile aqueous extract at 70$^{\circ}C$ (70AE, 96.61%) and S. thunbergii 20ME (97.44%) exhibited the highest scavenging activities against $O_2^{{\cdot}-}$, $HO^{\cdot}$, $H_2O_2$ and DPPH free radicals, respectively. Total phenolic contents also examined but did not show a positive correlation with ROS scavenging abilities (except for a few extracts). These results indicate that further investigation is needed to identify and purify the responsible antioxidative components.

• Fisheries and Aquatic Sciences
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• 제11권3호
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• pp.159-165
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• 2008

Intertidal benthic algal communities on the shores of Gujido and Daeyeonpyeongdo islets, Korea, were examined in October 2007. At both sites, 45 seaweeds including 7 green, 6 brown and 32 red algae were identified. The number of species at Gujido(38 species) was 1.5 times higher than at Daeyeonpyeongdo(25 species), but seaweed coverage was very similar with about 20%. Dominant seaweeds in terms of coverage and importance value were Hildenbrandtia sp., Caulacanthus okamurae, Ulva pertusa, and Gelidium amansii at Gujido and U. pertusa, Hildenbrandtia sp., Gelidium divaricatum at Daeyeonpyeongdo. The vertical distribution pattern of the seaweeds was G. divaricatum-U. pertusa, Hildenbrandtia sp.-U. pertusa, Hildenbrandtia sp., Ishige okamurae from upper to lower intertidal zone but seaweed zonations were not observed on the Gujido rocky shore. At both sites, coarsely-branched forms were the dominant functional group in species number and percent cover(among benthic algal species). The rocky shores of the two sites were dominated by crustose coralline and green algae, whose presence generally results in decreased seaweed biodiversity and community stability. Therefore, the shores of the Yeonpyeongdo islets are of considerable environmental concern and should be monitored for seaweed species composition and community structure.