• Preventive Nutrition and Food Science
• /
• v.10 no.2
• /
• pp.134-139
• /
• 2005

Seven brown algal species (Ecklonia cava, Ishige okamurae, Sargassum fulvellum, Sargassum horneri, Sargassum coreanum, Sargassum thunbergii and Scytosiphon lomentaria) were hydrolyzed using five proteases (Protamex, Kojizyme, Neutrase, Flavourzyme and Alcalase) and screened for angiotensin 1-converting enzyme (ACE) inhibitory activities. Most algal species examined showed good ACE inhibitory activities after the enzymatic hydrolysis. However, E. cava was the most potent ACE inhibitor of the seven species. Flavourzyme digest of E. cava exhibited an $IC_{50}$ of around $0.3\;{\mu}g/mL$ for ACE; captopril has an $IC_{50}$ of $\~0.05\;{\mu}g/mL$. The Flavourzyme digest was separated to three fractions by an ultrafiltration membrane (5, 10, 30 kDa MWCO) system according to the molecular weights. The active components were mainly concentrated in >30 kD fraction which are composed of the highest protein content $(27\%)$ and phenolic content (261 mg/100 mL) compared to the other two smaller molecular weight fractions. Therefore, the active compounds appear to be relatively high molecular weight complex molecules associated with protein (glycoprotein) and polyphenols. Therefore, E. cave is a potential source of antihypertensive compound.

• Korean Journal of Pharmacognosy
• /
• v.28 no.4
• /
• pp.239-246
• /
• 1997

The methanol extracts of some marine algae were tested for investigating the effects on the formation of lipid peroxide and the activities of free radical generating enzyme in vitro in bromobenzene-treated rat. The extracts of Enteromorpha compressa, Capsosiphon fulvescens, Gelidium amansii, Hizikia fusiformis, Sargassum siliquastrum and Sargassum thunbergii which decreased the formation of lipid peroxide, inhibited the activity of xanthine and aldehyde oxidases by adding of each extracts. Phloroglucinol isolated from Ecklonia stolonifera reduced bromobenzene-induced hepatic lipid peroxidation. This compound administered daily over one week before intoxication with bromobenzene did not affect the activities of aminopyrine N-demethylase, aniline hydroxylase and glu tathione S-transferase. Epoxide hydrolase activity was decreased by bromobenzene, which was restored by pretreatment of phloroglucinol, The results suggest that the bromobenzene-induced hepatic lipid peroxidation by phloroglucinol is reduced by enhancing the activity of epoxide hydrolase.

• Journal of Plant Biology
• /
• v.29 no.3
• /
• pp.175-183
• /
• 1986

Marine algal flora and intertidal vegetation around Samchonpo power plant, south coast of Korea, were investigated at three sites, specially referred to the seasonal variation of the species from April to October, 1982. A total of 84 species were identified; 8 green, 19 brown and 57 red algae. Among three sampling sites investigated, 65 species were collected at the first site located in front of the power plant, 66 at the second site, Namildae beach, and 61 at the third, Sinsudo, respectively. The algal vegetation at the first site was dominated in cover by Sargassum thunbergii and Ulva pertusa in April, Corallina spp. Ulva pertusa in July, and Chondria crassicaulis and Ulva pertusa in October. At the second site, it was dominated in cover by Sargassum thunbergii, Gigartina tenella and Ulva pertusa in April, Sargassum thunbergii and Ulva pertusa in July, and Chondria crassicaulis and Ulva pertusa in October, whereas at the third site Sargassum thunbergii and Ulva pertusa in April, and Chondria crassicaulis in October, respectively. The biomass among three investigated sites showed 2,360 g-fresh wt/$m^2$ on an average; 283 g-dry wt/$m^2$ at the first, 277 g-dry wt/$m^2$ at the second, and 256 g-dry wt/$m^2$ at the third site, respectively.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.56 no.5
• /
• pp.684-690
• /
• 2023

This study was conducted bimonthly from February to December 2021 to reveal the ecology of Sargassum thunbergii in the intertidal zone along the coasts of Korea. Separate surveys on the period of embryo formation were conducted from February 2021 to December 2022. The growth of S. thunbergii began to increase in February, reached a maximum in June, and was at a minimum in October. Air vesicles were formed from February to June, April to August, and February to August on the east, west, and south coasts, respectively. Receptacles were observed from April to June on the east coast, but from April to August on the west and south coasts. The earliest release of embryos was observed in late May 2022 on the south coast, followed by early June on the east and west coasts. The average size of leaves, stems, and air vesicles was maximum on the east coast and minimum on the west coast, whereas leaf and internode intervals were maximum on the west coast and minimum on the east coast. Plant length, biomass, and the number of branches showed maximum values in the south coast and minimum values in the east coast.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.16 no.4
• /
• pp.379-388
• /
• 1983

The subtidal benthic algal communities of Dolsan-island in the southern coast of Korea were surveyed by means of SCUBA diving. The vertical zonation is recognized into three groups; upper, middle and lower subtidal zones. The representative species in each group throughout the year are Ulva pertusa, Codium fragile, Chondria crassicaulis and Gigartina tenera in the upper, Myagropsis myagroides and Sargassum tortile in the middle, and Plocamium telfairiae, Callophyllis japonica and Symphyocladia linearis in the lower zone. According to the normal association analysis by $2{\times}2$ contingency table and chi-square calculation among 29 quadrats, the algal communities are divided into 9 groups which are dominated by Sargassum tortile, Myagropsis myagroides, Chondria crassicaulis, Codium fragile, Pterocladia tenuis, Gigartina tenera, Gracilaria textorii. The thallus length and standing crops of Myagropsis myagroides show the highest value in spring and the lowest in summer.

• 한국해양학회지
• /
• v.26 no.2
• /
• pp.108-116
• /
• 1991

A production model was constructed by combining the production rate and biomass of Sargassum confusum measured at monthly intervals on the coast of Ohori, Korea, to estimate the algal production for a given period. The production for a certain period, e.g., for a year (P/SUB yr/), was calculated from the equation: P/SUB yr/ = .int.P/SUB t/$.$B/SUB t/dt, where pl and Bl are the production rate and biomass at time t. P/SUB l/ was considered as a function of temperature and light. Photosynthesis-Irradiance curves obtained from the in situ experiments were applied for P/SUB l/ Temperature and light intensity can be expressed as periodic functions of time (T, L=f(t)). Diurnal values of water temperature and light intensity at 3 m depth where S. confusum mainly found were substituted into the equation of P/SUB l/. Simulations using our models show that temperature was one of the most sensitive factors operating on the primary production. Thirty percent decrease of light intensity by cloud cover was estimated to decrease the annual production by 5%.

• Analytical Science and Technology
• /
• v.12 no.3
• /
• pp.196-202
• /
• 1999

Brown algae, Sargassum horneri, was used as an adsorbent to remove heavy metal Cd(II) and Pb(II) ions. Sargassum horneri picked in East Coast was formulated into the grain with the size of 40-60 mesh after wind dry. Batch method was used in order to investigate the adsorption rate by measuring the adsorption amounts with shaking time. In the column method, the adsorption amounts were measured by flowing metal solutions into the algae-packed column at the rate of 1 ml/min. Adsorption amounts in both batch method and column method were in the following order : pH 10.5>7.0>3.5. It was found that Pb(II) was more adsorbed on the algae grain than Cd(II). It was also revealed that the adsorption amounts reached the maximum within 5 minutes irrespective of pH condition in the batch method. It was concluded that the batch method was more effective than the column method in terms of recovery rate.

• ALGAE
• /
• v.23 no.4
• /
• pp.327-334
• /
• 2008

Seaweed biomass was estimated using a nondestructive sampling method in the rocky intertidal and subtidal zone in Daejin on the mid-east coast of Korea from August 2006 to April 2008. Seasonal sampling were done at the depth of 0, 1, 5, 10 m using 50 x 50 cm quadrat. A total of 95 species, including 11 chlorophytes, 26 phaeophytes, 57 rhodophytes and one sea grass were identified. Mean biomass was comprised of 1,292 g wet wt m$^{-2}$ and the biomass values varied seasonally from 904 g to 1,945 g. Dominant species in biomass were Sargassum spp. (S. horneri, S. yezoense), Corallina pilulifera, Phyllospadix japonica, Symphyocladia latiuscula, Hizikia fusiformis, Codium arabicum and Chondrus ocellatus at Daejin. The vertical distribution of algae were characterized by Corallina pilulifera, Symphyocladia latiuscula, Sargassum spp. (S. confusum, S. yezoense), Hizikia fusiformis and Grateloupia elliptica at intertidal zone, Sargassum spp. (S. fulvellum, S. horneri, S. yezoense), Phyllospadix japonica, Codium arabicum, Undaria pinnatifida and Corallina pilulifera at 1 m depth, Sargassum spp. (S. horneri, S. micracanthum, S. yezoense), Phyllospadix japonica, Grateloupia elliptica, Gelidium amansii and Codium arabicum at 5 m depth and Phyllospadix japonica, Codium arabicum, Sargassum spp. (S. horneri, S. micracanthum, S. yezoense) and Undaria pinnatifida at 10 m depth.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.10 no.4
• /
• pp.189-197
• /
• 1977

In present study, the effects of various factors including the solvent concentration, extraction time and temperature, the ratio of sample vs extraction solvent, (w/v) and pH upon the extractability of the NaCl and alcohol soluble proteins of marine algae were investigated. Eight species of fresh algae, the major ones in consumption as food, namely Porphyra suborbiculata, Undarie pinnatifida, Hizikia fusiforme, Sargassum, fulvellum, Enteromorpha linza, Sargassum kjellmanianum, Codium coarctatum, and Ulva pertusa were used for the extraction of NaCl soluble protein and dried materials of four species, Perphyra suborbiculata, Undaria pinnatifida, Enteromorpha linza and Sargassum fulvellum were used for the extraction of alcohol soluble protein. The frozen and mascerated samples were prepared by the same method described in previous paper (Ryu, 1977). And the dried materials were moistened with alcohol solution before freezing. The effect of solvent concentration on the extractability of NaCl soluble protein differed from species. The extractability of Undaria Pinnatifide, Hizikia fusiforme, Perphyra suborbiculata, Enteromorpha linza, and Ulva pertusa reached maxima at 0.25M NaCl solution while the 1.0M for Sargassum fulvellum, Saygassum kjellmanianum and Codium coarctatum. In case of alcohol soluble proteins, it was shown at $20\%$ ethanol solution for Porphyra suborbiculata, Undaria pinnatifida, Enteromorpha linza, and Sargassum fulvellum. Variation of the ratio of sample vs solvent gave slight effect upon the extractability, but the ratio of 1:30(w/v) seemed most efficient for the extraction of NaCl soluble proteins and 100 ml solvent added to 1 g dried sample was effective in case of alcohol soluble proteins. Extraction time has a minimal effect upon the extraction of alcohol soluble protein, and approximately 21 to $43\%$ of algal protein was extracted within 1 hour. But in case of NaCl soluble protein extraction, the effect of time revealed differently from species to species resulting in that the extraction for 1 hour gave a maximum extractability in Ulva pertusa and Enteromorpha linza, 2 hours in Porphyra suborbiculata, Codium coarctatum and 3 hours in Undaria pinnatifica, Hizikia susiforme, Sargassum fulvellum and Sargassum kjellmanianum. When the NaCl soluble protein of Undaria pinnatifida and Enteromopha linza was extracted at various temperature, the most effective extraction temperature was $40^{\circ}C$ while the temperature was $50^{\circ}C$ for Undaria pinnatifida and $60^{\circ}C$ for Hixikia fusiforme, Sargassum fulvellum, Sargassum kjellmanianum and Codium coarctatum. Bus in case of alcohol soluble extraction, the optimum temperature was $30^{\circ}C$ for Enteromorpha linza and $40^{\circ}C$ for Undaria pinnatifida, Sargassum fulvellum and Porphyra suborbiculata. In the effect of pH on extractability, the maximum extractability of NaCl soluble proteins was obtained at pH 7to 8 and pH 8 to 9 for alcohol soluble protein.

• Ocean and Polar Research
• /
• v.25 no.1
• /
• pp.129-132
• /
• 2003

The crude extracts of marine algae were screened for tyrosinase-inhibitory and radical scavenging effects. Among the samples tested, Symphyocladia latiuscula and Gloiopeltis furcata were found to be the most effective in DPPH radical scavenging test while Gigatina tenella, Sargassum thunbergii, and Sargassum sp. were moderately active. For the inhibition against mushroom tyrosinase, Symphyocladia latiuscula and Sargassum confusum showed the strongest inhibition. Codium adhaerens, Corallina pilulifera, Carpopeltis cornea, Halymenia acuminata, Hizikia fuziformis, Porphyra suborbiculata, and Enteromorpha linza exhibited mild inhibitory potency.