• ALGAE
• /
• v.32 no.1
• /
• pp.1-13
• /
• 2017

Seaweed aquaculture technologies have developed dramatically over the past 70 years mostly in Asia and more recently in Americas and Europe. However, there are still many challenges to overcome with respect to the science and to social acceptability. The challenges include the development of strains with thermo-tolerance, disease resistance, fast growth, high concentration of desired molecules, the reduction of fouling organisms and the development of more robust and cost efficient farm systems that can withstand storm events in offshore environments. It is also important to note that seaweed aquaculture provides ecosystem services, which improve conditions of the coastal waters for the benefit of other living organisms and the environment. The ecosystem services role of seaweed aquaculture and its economic value will also be quantitatively estimated in this review.

• ALGAE
• /
• v.21 no.1
• /
• pp.149-156
• /
• 2006

The aim of the present study was to evaluate the antioxidant activity of red algae in Jeju Island. The algal extracts were obtained with MeOH and fresh water at 20 and 70°C, and screened for antioxidant activities using hydroxyl radical (HO·), superoxide anion (O2–), hydrogen peroxide (H2O2) and DPPH free radical scavenging assays. Among them, Gracilaria verrucosa methanolic extract at 20°C (20ME, 96.85%), G. textorii aqueous extract at 20°C (20AE, 88.01%), Grateloupia filicina 20AE (85.35%), and Polysiphonia japonica 20ME (94.92%) exhibited the highest scavenging activities against HO·, O2–, H2O2, and DPPH free radicals, respectively. Moreover, P. japonica (20ME and 70ME) is correlated between DPPH free radical scavenging activity and polyphenolic contents. These results indicate that some red algae in Jeju Island could be potential candidates for development of antioxidants.

• ALGAE
• /
• v.21 no.3
• /
• pp.343-348
• /
• 2006

This study was conducted to screen in vitro angiotensin - I converting enzyme (ACE) inhibitory activities of methanol (MeOH) and aqueous extracts at 20°C and 70°C, respectively, prepared from twenty-six red algae obtained from the coast of Jeju Island in Korea. Among aqueous extracts at 20°C (20AE) from red algae Lomentaria catenata showed the strongest ACE inhibitory activity and Lithophyllum okamurae recorded the second highest activity. From MeOH extract at 20°C (20ME) Ahnfeltiopsis flabelliformis possessed the strongest ACE inhibitory activity. Remarkable activities from MeOH extracts at 70°C (70ME) were observed in Grateloupia filicina, Sinkoraena lancifolia and Grateloupia lanceolata. However, no significant activity was found in aqueous extracts at 70°C (70AE). The IC50 values, which are concentrations required to inhibit 50% activity of ACE, for ACE inhibitory activities of 20AE from Lithophyllum okamurae and L. catenata were 13.78 and 12.21 μg mL–1, respectively. The IC50 values of 20ME from A. flabelliformis and Laurencia okamurae were 13.84 and 106.15 μg mL–1. Those of the 70ME from Bonnemaisonia hamifera, Grateloupia filicina, Sinkoraena lancifolia, G. lanceolata, Gracilaria vermiculophylla and L. okamurae ranged from 25.82 to 124.69 μg mL–1.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.2 no.2
• /
• pp.134-138
• /
• 1969

Experiments were carried out to asses the impotance of environmental conditions upon the growth rate, length compositions seedling and spore liberation of a red alga Glacilaric verrucosa. The alga grown in water of low salinity mixed with fresh water shows better growth rate, lager length composition and excellent seedling, whereas the one vegetated in an area of tidal exposure shows a somewhat retarded growth rate and poor seedlings. The rate of growth Increases from August to October and begins to diminish from December continuing to diminish through February. Therefore the spore settling time extends from May to lune. Although the sun-drying method is the most eacient way of inducing spore liberation, further investigations are necessary in oiler to use this method for the application to artificial spore settling.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.48 no.1
• /
• pp.88-95
• /
• 2015

The three endophytes, Blastophysa rhizopus, Bolbocoleon piliferum, Ulvella leptochaete, were isolated in a laboratory culture from a Grateloupia lanceolata thallus collected in Jeju. Effects of temperature and irradiance on growth and infection of the three species, were examined. Based on the unialgal cultures, their growth was examined under six temperatures (9, 13, 17, 21, 25, $29^{\circ}C$) and two irradiance levels (60, $100{\mu}mol\;m^{-2}s^{-1}$). Also, infection experiments to the five hosts (Ulva intestinalis, Scytosiphon lomentaria, Gracilaria verimiculophylla, Chondrus ocellatus, and Grateloupia elliptica) with three endophytes were carried out under four temperatures (10, 15, 20, $25^{\circ}C$) and two irradiance levels (60, $100{\mu}mol\;m^{-2}s^{-1}$). In culture of the endophytes, optimum growth was found in $100{\mu}mol\;m^{-2}s^{-1}$ in combination with $21^{\circ}C$. At the end of infection experiment, endophytes were observed at all the hosts. Among three endophytes, U. leptochaete was the most common at the five hosts. However, we did not observe any endophytes at all hosts tested under $10^{\circ}C$ condition. Based on this result, it appears that temperature acts as a limiting factor to infection of the three species.

• The Journal of Economics, Marketing and Management
• /
• v.6 no.4
• /
• pp.41-49
• /
• 2018

Purpose - The purpose of the study was to investigate restaurants increasing seaweed of marine products and to let consumers live healthy and happy lives and to discuss increase of seaweeds consumption. The purpose of the study was to give consumers good food and to live healthy and happy life and to elevate life quality and to produce added value by increase of consumption of seaweeds such as laver, brown seaweed, tangle and gracilaria and others and to give economic advantage. The seaweed could be produced in large quantity without spending of much money in accordance with demand to make use of it at restaurants. Research design, data, and Methodology - The author visited restaurant businessmen at Suwon, Anyang, Hwaseong and Yongin to investigate low sales by in-depth interview. The study investigated Kodari-jorim restaurants that made use of laver ssam for side dish. The subject was HS distributors to let restaurant keepers think of seaweeds and replacement of vegetable by seaweed. Results - Women customers who thought of health and diet usually selected menu at the restaurants not to appeal. Conclusions - Menu with high quality seaweeds (low calory, satiety and health) can satisfy women customers thinking much of health and diet to increase consumption of seaweeds. The study was exploratory to investigate in qualitative and quantitative way in the future.

• Nuclear Engineering and Technology
• /
• v.8 no.3
• /
• pp.145-150
• /
• 1976

Alkali-treated red algae, Gracilaria sp. was irradiated with various doses of cobalt-60 gamma-rays and the yeild and properties of agar extracted from the seaweed were examined and compared with the quality of commercial agar powder after irradiation. Extraction yield of agar from irradiated seaweed was proportionally increased as the radiation dose was raised up to 2 Mrad whereas it tended to decrease slightly thereafter. Gelation ability, gelation point, gel hardness and specific viscosity of the agar were increased up to 1 Mrad and decreased at higher dose levels while its melting point, total nitrogen, crude ash and total sulfur decreased up to 1 Mrad level and remained unchanged thereafter. Irradiation of commercial agar powder caused remarkable decreases in the gelation ability, specific viscosity and gel hardness and slight decreases in the gelation point and melting point. The pattern of alterations in the properties of agar samples differed whether the polysaccharide was irradiated in free state or bound state in seaweed.

• Proceedings of the Korean Society of Applied Pharmacology
• /
• 1994.04a
• /
• pp.211-211
• /
• 1994

항종양성 화합물의 개발을 지향한 해양생물 유래의 생물활성 물질의 화학적 연구의 일환으로써 다양한 종류의 생물활성 (즉, 항균작용, 혈중콜레스테롤 저하작용)등을 나타내며, 구입수가 용이한 홍조 꼬시래기 (Gracilaria verrucosa) 및 갈조 지충이 (Sargassum thunbergii)의 아세톤 및 메탄올 엑스를 EtOAc 및 n-BuOH로 분획한후 각 분획을 SiO$_2$ column, TSK gel(Toyo pearl HW-40F), $\mu$-Bondapak column 및 HPLC등으로 분리 정제하여, 새로운 glyceroglycolipid(GV-5, -6, ST-6) 및 glycerylglycoside(GV-12)를 얻었다. 이렇게 분리된 화합물의 물리화학적 성질, 화학반응 및 분광학적 data를 종합 검토한 결과 GV-5, -6, -12, 및 ST-6은 각각 1,2-diacyl-3-0-($\alpha$-D-galactopyranosyl) glycerol (acyl : palmitate-oleate-arachidonate 4: 1 : 9) (1), 1,2-diacyl -3-0-〔$\alpha$-D-galactopyranosyl -(1 "$\longrightarrow$6')-0-$\beta$-D-galactopyranosyl〕 glycerol (acyl : palmitate-oleate-arachidonate(5:1:4)(3), 2-0-($\alpha$-D-galactopyranosyl) glycerol (5), 및 sodium salt of 1-acyl-3-0-(6'-sulfo-$\alpha$-D-quinovopyranosyl) glycerol(acyl:palmitate-oleate 96:4)(8) 이라는 것이 판명되었다. 그리고 GV-5 및 -6은 마우스 백혈병세포 (L1210)에 대한 세포독성 ($IC_{50}$/ of GV-5, and -6:8.0$\mu\textrm{g}$/ml and 10.8$\mu\textrm{g}$/ml )외에, 사람의 상피암세포에 대한 성장억제효과 [growth inhibitor(%) in 20$\mu\textrm{g}$/m1 :GV-5(39.9%), GV-6(16.7%)를 나타내었으며, 한편, GV-5, GV-6, -12 및 ST-6은 각각 쥐의 F9 기형암종 세포의 분화유도 활성을 나타내어 항종양제로의 개발에 많은 흥미가 기대된다.기대된다.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.47 no.3
• /
• pp.274-282
• /
• 2014

We examined seasonal variation in the structure of marine macroalgal communities at five sites around the Byeonsan Peninsula, Korea, from January to October 2011. Sixty eight species were identified, including 11 green, 17 brown and 40 red algae. Species richness was highest at Gyeokpo (51 species) followed by Sambal (47), Gosapo (34), Byeonsan (33), and Habgoo (18). Seaweed biomass ranged from 12.98 to 145.33 g dry $wt/m^2$, with maximum and minimum biomasses at Gyeokpo and Habgoo, respectively. Sargassum thunbergii was the representative alga species occupying 47.89% of the total biomass. The dominant seaweeds were S. thunbergii, Corallina pilulifera, Ulva spp, Gracilaria vermiculophylla, and Carpopeltis affinis. No distinctive vertical distribution of seaweeds was found because S. thunbergii, Ulva spp, and G. vermiculophylla were all distributed from high to low shore. Community indices were as follows: dominance index (DI), 0.44-0.61; richness index (R), 6.27-10.35; evenness index (J'), 0.38-0.59; and diversity index (H'), 1.48-1.71. Gyeokpo had the most biomass and highest species richness, and the lowest percentage of Ulva species. However, species richness declined at Gyeokpo, from 78 to 51 species within 10 years, implying that eutrophication and sedimentation from Mankyeong and Dongjin rivers have reduced the stability of seaweed communities.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.53 no.3
• /
• pp.388-394
• /
• 2020

An emerging interest in healthy eating has led to an increase in the consumption of rice mixed with various types of grains. Cooked rice was prepared with five different seaweeds, Hizikia fusiformis, Sargassum fulvellum, Enteromorpha compressa, Undaria pinnatifida, and Gracilaria verrucosa, and the antioxidant activity was measured. In addition, the antioxidant activities of 80% ethanol and methanol extracts of the five seaweeds were compared. Total phenolic content (TPC), total reducing power (TRP), 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azino-bis-3-ethylbenzthiazoline-6-sulphonic acid (ABTS) cation radical scavenging activities of the ethanol extracts were higher than those of the methanol extracts. The TPC of raw seaweed ethanol extracts was from 7.58 to 26.27 mg gallic acid equivalent (GAE)/g. The antioxidant activities of both extracts of Hizikia fusiformis were the highest among the five seaweeds, and the antioxidant activities of the cooked rice were lower than those of the raw seaweed extracts. The DPPH radical scavenging activities of cooked white rice, mixed grains, barley, and a mixture of white rice and barely added with Hizikia fusiformis, Sargassum fulvellum and Undaria pinnatifida were 3.17, 23.12, 31.11 and 10.66%, respectively. These results demonstrate the addition of seaweeds to cooked rice helps to improve the antioxidant activity compared to white rice alone.