• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.43 no.6
• /
• pp.679-686
• /
• 2010

To investigate the contribution of macroalgae to biogeochemical nutrients and carbon cycles, we measured the uptake rates of nutrients and $CO_2$ by Undaria pinnatifida using an incubation method in an acrylic chamber. From January to March 2010, U. pinnatifida was sampled at Ilkwang, a well-known area of macroalgae culture in Korea. The initial and final concentrations of nutrients, dissolved oxygen, total alkalinity, and pH of the chamber water were measured, and production/uptake rates were calculated using concentration changes, chamber volume, and incubation time. The production rate of dissolved oxygen by U. pinnatifida (n = 32) was about $5.4{\pm}4.0\;{\mu}mol\;g_{fw}^{-1\;}h^{-1}$. The uptake rate of total dissolved inorganic carbon (TDIC), calculated by total alkalinity and pH, was $7.9{\pm}6.5\;{\mu}mol\;g_{fw}^{-1}\;h^{-1}$. Nutrients uptake averaged $141.7{\pm}119.2$ nmol N $g_{fw}^{-1}\;h^{-1}$ and $15.0{\pm}9.1$ nmol P $g_{fw}^{-1}\;h^{-1}$. A positive linear correlation ($r^2$ = 9.6) existed between the production rate of dissolved oxygen and the uptake rate of total dissolved inorganic carbon, suggesting that these two factors serve as good indicators of U. pinnatifida photosynthesis. The relationships between fresh weight and uptake rates of nutrients and $CO_2$ suggested that younger specimens (<~50 g fresh weight) are much more efficient at nutrients and $CO_2$ uptake than are specimens >50 g. The amount of carbon uptake by the total biomass of U. pinnatifida in Korea during the year of 2008 was about 0.001-0.002% of global ocean carbon uptake. Thus, more research should be focused on macroalgae-based biogeochemical cycles to evaluate the roles and contributions of macroalgae to the global carbon cycle.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.32 no.3
• /
• pp.284-289
• /
• 1999

A 15-week feeding trial was conducted to investigate the effect of formulated diet or macroalgae (Undaria pinnatifida) on the survival, growth and body composition of juvenile abalone (Haliotis discus hannai) under the different rearing environmental conditions (four shelter types and two water temperatures). Water temperature was maintained to $16.4^{\circ}C$ by heated and $13.7^{\circ}C$ by not heated natural sea water. The survival rate, weight gain and shell growth of abalone were affected by diet and water temperature (P<0.001). Survival rate of abalone fed the formulated diets was higher than that of abalone fed the Undaria pinnatifida at natural sea water (P<0.05), but this value was not influenced within abalone stocked at heated sea water in each shelter group (P>0.05). Weight and shell growth of abalone fed the formulated diets were significantly higher than those of abalone fed the Undaria pinnatifida at each temperature or shelter (P<0.05). Moisture, lipid and ash contents of the soft body were mainly affected by feeding diet than temperature or shelter (P<0.05). This study indicate that formulated diet used in this experiment could improve the growth of abalone independent of water temperature or shelter. and heated water could show a better growth of abalone in winter season.

• Journal of Plant Biology
• /
• v.38 no.2
• /
• pp.153-158
• /
• 1995

Community structure of subtidal macroalgae was investigated at 3 sites of Neobdo Island in August 1994. In total, 66 taxa of red, 21 brown, 14 green, and 2 blue-green algae were identified. The number of species and biomass decreased with increasing depths. Gelidium amansii, Ulva pertusa, Dictyota dichotoma, Sargassum thunbergii, Undaria pinnatifida, Ecklonia cava, and Sargassum horneri had higher frequency and biomass. The vegetation of deeper zone was composed mainly of a few red algae. Substrate characteristic and light intensity were considered as environmental factors determining the underwater vegetation.

• Journal of Environmental Science International
• /
• v.24 no.10
• /
• pp.1285-1307
• /
• 2015

We constructed marine forest to restore barren grounds which are expanding in the east coast of Korea using 2 methods of (1)seedlings transplantation method and (2)underwater floating ropes method. We transplanted 3 macroalgae species, Ecklonia cava, Undaria pinnatifida, and Saccharina. japonica to construct marine forest. Blade length of Undaria pinnatifida on underwater floating ropes was $56.70{\pm}8.69mm$ in April and grew $68.75{\pm}22.30mm$ in May and $70.75{\pm}14.36mm$ in July. Blade length of S. japonica was shown 97.95-143.00mm in April to June. Blade length of Ecklonia cava was $30.50{\pm}1.91mm$ in May, $41.55{\pm}1.84mm$ in August, $45.30{\pm}2.57mm$ in November, 2009 and $45.30{\pm}1.99mm$ in February, 2010. The survey on Dangsa area, Ulsan-city in January, 2009 found a total number of 15 algal species(1 brown algae, 14 red algae species) with the highest variety at 5m depth of A station and the lowest at 8m depth of A and B stations. The March survey showed a total of 24 species (1 green algae, 1 brown algae, 22 red algae species) with the highest variety of 11 at depths of 3m and 5m of B station and the lowest of 6 at 10m of B station. In May, total biomass was 3,755.4g (green algae 1.2g, brown algae 199.0g, red algae 3,555.2g). From January, 2009, we found that E. cava was dominant at the depths of 3m and 5m of A and B stations while Peyssonnelia capensis was dominant at the depth of 8m of A station. The 8m depth of B station was dominated by Acrosorium polyneurum. In May, Grateloupia lanceolata was dominant at 8m depth of A station while other depths were dominated by Phycodrys fimbriata. In June, the dominant species were G. lanceolata at the 3m depth, E. cava at the 5m and P. fimbriata at the depths of 8m and 10m of A station. Under B station, G. lanceolata was dominant at the depths of 3m and 5m while P. fimbriata was dominant at the depths of 8m and 10m.

• Journal of Aquaculture
• /
• v.1 no.2
• /
• pp.121-133
• /
• 1988

Strongylocentrotus pulcherrimus is one of the very important fishery stock in this country since its high demand for raw gonad. Although the demand has been continuously increasing, the natural stock of this species seems to be decreasing. Since fresh macroalgae are not always available, the substitution of terrestrial vegetables for algae as a principal food was examined for the intensive indoor culture of the sea urchin. The results from the studies on selective and non-selective feeding habits and nutritional efficiencies using 13 food stuffs (6 macroalgae, 5 vegetables and 2 animal products) indicate that algae can be substituted with vegetables in sea urchin culture. Although the growth of body weight was the highest when sea urchins were fed Undaria Pinnatifida, the gonad index of the sea urchins fed on spinach, radish leaf and lettuce was higher than that of this brown alga. Considering the different food efficiencies of body and gonad growth, spinach and radish leaf will be adequate during gonad growth season, while lettuce and Chinese cabbage will be suitable for test growth season. In particular, radish leaf, which is usually not eaten by humans, could be highly beneficial and very economical in the sea urchin culture.

• Fisheries and Aquatic Sciences
• /
• v.21 no.9
• /
• pp.26.1-26.8
• /
• 2018

Inclusion effect of soybean meal (SBM) and fermented SBM (FSM) in extruded pellet for juvenile abalone (Haliotis discus) was compared in abalone farm. Dietary inclusion effect of the combined macroalgae (MA) (Undaria pinnatifida and Hizikia fusiforme) and a single Saccharina japonica on abalone was also compared. Three thousand six hundred juvenile abalone were purchased from a private hatchery and acclimated to the experimental conditions for 2 weeks. Six 5-ton flow-through raceway tanks were used, and abalone were randomly distributed into tanks (n = 600 per tank). Three experimental diets were prepared in duplicate. Fish meal, FSM, corn gluten meal, and shrimp meal and wheat flour and dextrin were used as the protein and carbohydrate sources, respectively, in the FSM diet. MA was also included in the FSM diet. FSM and MA in the FSM diet were substituted with SBM at the expense of wheat flour and S. japonica, referred to as the SBM and SJ diets. The experimental diets were pelletized by an extruded pelleter. Water stability of nutrients in the experimental diets was monitored at 12, 24, and 48 h after seawater immersion. The experimental diets were fed to abalone once a day to satiation with a little leftover for 120 days. The retained crude protein and lipid and ash content of the extruded pellets were changed over all period of time. Weight gain and specific growth rate (SGR) of abalone fed the SBM diet were greater than those of abalone fed the FSM and SJ diets. Weight gain and SGR of abalone fed the SJ diet were also greater than those of abalone fed the FSM diet. The longest shell length, widest shell width, highest shell height, and greatest soft body weight were obtained in abalone fed the SBM diet, followed by the SJ and FSM diets. Proximates of the soft body of abalone were not different among the experimental diets. In conclusion, SBM was a superior protein source to FSM in extruded pellet for growth performance of abalone. Dietary inclusion of a single S. japonica was superior to the combined inclusion of U. pinnatifida and H. fusiforme in the production of abalone.

• Journal of Practical Agriculture & Fisheries Research
• /
• v.22 no.2
• /
• pp.69-79
• /
• 2020

In this study, the anti-inflammatory and cytotoxic effects of hot-water extracts from 10 kinds of macroalgae in Korea were investigated. It was selected materials in consideration of biological activity and industrial potential as follows: Caulerpa okamurae; Codium fragile; Ulva australis; Ishige foliacea; Saccharina japonica; Sargassum horneri; Undaria pinnatifida; Gloiopeltis tenax; Gracilaria verrucosa; Porphyra tenera. Results showed that S. japonica and G. tenax significantly decreased NO productionn in LPS-stimulated Raw 264.7 cells at concentrations of 100, 1000 ㎍/mL and 1000 ㎍/mL, respectively. However, most of the other macroalgae used in the experiment did not affect NO production. It was observed that all macroalgae extracts except for the highest concentration (1000 ㎍/mL) treatment group of P. tenera did not affect the viability in Raw 264.7 cells. In addition, there was not significant decrease in cell viability by macroalgae extracts treatment in HINAE cells. These results suggest that S. japonica and G. tenax could be used as potential safe natural anti-inflammatory agents for food and feed additives. Also, the results of this study are expected to be used as basic data for the development of functional materials for 10 kinds of macroalgae resources in Korea.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.56 no.5
• /
• pp.691-700
• /
• 2023

This study examined the seasonal variations of subtidal marine algal community structures along four sites in Jejudo Island, Korea, from February 2016 to November 2018. A total of 147 marine algal species were identified, including 13 green (8.84%), 26 brown (17.69%), and 108 red algae (73.47%). During the study period, the number of species was highest in Sagye (116 species) followed by numbers in Sinheung (98 species), Bukchon (90 species) and Sinchang (73 species). Ecklonia cava, Peyssonnelia caulifera, Synarthrophyton chejuense, Corallina aberrans and Corallina crassisima occurred at all study sites and in all seasons. The average annual biomass of marine algal flora was 746.29±88.85 g wet wt./m² and ranged from 652.25 g/m² at Sinheung to 979.91 g/m² at Sagye. The brown alga E. cava was the most dominant species, occupying 42.85% (319.80 g/m²) of the total seaweed biomass. Subdominant species were C. crassissima and Undaria pinnatifida, comprising 10.22% (76.29 g/m²) and 9.66% (72.13 g/m²), respectively. A similarity analysis showed that there were regional differences in the algal communities, with three distinct groups.