• ALGAE
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• 제25권4호
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• pp.205-216
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• 2010

The marine red alga Kappaphycus alvarezii is a major source of $\kappa$-carrageenan. It has been introduced in 20 countries including India. Recently, several reports have expressed concerns about Kappaphycus invasion on Acropora corals at Kurusadai Island in the Gulf of Mannar, India, which is part of a marine bioreserve. To understand the extent of the Kappaphycus invasion, 27 randomly selected locations around Kurusadai Island and the mainland coast were surveyed during May-August 2008 and July 2009. Our rigorous sampling revealed that K. alvarezii was confined to two different patches of 105 m $\times$ 55 m and 8 m $\times$ 9 m located at the southeastern part of Kurusadai Island. The actual extent of the K. alvarezii canopy coverage was 76.7 $m^2$, accounting for less than 0.0035% of the total coral reef area. The daily growth rate of the K. alvarezii at Kurusadai was 0.7%. K. alvarezii was not observed in the coral reef area of the adjoining Pullivasal and Poomarichan Islands or the Palk Bay area cultivation sites. The lack of functional reproductive cycle, low spore viability, and the absence of microscopic phases in the life cycle of this alga coupled with the abundance presence of herbivores may restrict the further spread of this alga, so its invasive potential at Kurusadai Island is considered remote.

• 수산해양교육연구
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• 제26권2호
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• pp.444-454
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• 2014

The range of optimization problem in aquaculture is very wide, resulting from the range of species, mode of operation. Quite a few studies focus marine net-cages, but studies on land based culture farm are few or no. This paper considers a allocation problem to meet production planning in land based aquaculture system. A water pool allocation model in land based aquaculture system was developed. The solution finds the value of decision variable to minimize yearly production costs that sums up the water pool usage cost and sorting cost. The model inputs were (1) the fish growth rate (2) critical standing corp (3) number of water pool (4) number of fish. The model outputs were (5) number of water pool in growing phase (6) cost of cultivation (6) optimal facility allocation(number of water pool for each growing phase). To solve the problem, an efficient heuristic algorithm based on a greedy manner is developed. Branch and bound and heuristic is evaluated through numerical examples.

• Biotechnology and Bioprocess Engineering:BBE
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• 제6권5호
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• pp.359-362
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• 2001

The production of an extracellular polysaccharide, EPS-R, from the marine bacterium Hahella chejuensis was investigated at various aeration rates in a batch culture. Higher aeration rate resulted in enhanced EPS production and increased the viscosity of the culture broth. At an aeration rate of 1.5 vvm, EPS-R (12.2 g/L) was obtained with a yield (Y$\_$p/s) of 0.6 from the STN medium after 72 h of cultivation. The H. chejuensis cells changed rod morphology to a short-rod form in the stationary growth phase.

• Journal of Ecology and Environment
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• 제33권2호
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• pp.95-103
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• 2010

The archipelago in the southwest sea, Korea, was registered as Shinan Dadohae Biosphere Reserve by United Nations Educational, Scientific and Cultural Organization Man and the Biosphere (UNESCO MAB) on May 26, 2009. This study was conducted to determine a method of reconciling natural and anthropogenic processes and to enable sustainable development in the vicinity of the Shinan Dadohae Biosphere Reserve (SDBR). To accomplish this, the characteristics of SDBR with respect to biodiversity and cultural diversity were evaluated. In addition, a management plan regarding the wise use of the SDBR was developed while focusing on four parts: cultural support to induce motivation for native conservation and development; development and specification of fisheries and cultivation based on local community systems; restructuring of marine food products and resource transporting systems; activation and discovery of indigenous knowledge to enable networking between local residents, academia and the UNESCO-international society.

• ALGAE
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• 제35권2호
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• pp.107-121
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• 2020

Mariculture is regarded as the only option to supply the increasing demands for seaweeds as human food, feeds, fodder, and phycolloids in a sustainable manner. Technologies for culturing a range of seaweed species have been developed successively in Korea since the 1970s. In 2017, Korean marine farms produced 1,761,526 t of seaweed. The key focus of the industry is on the production of Pyropia (523,648 t), Undaria (622,613 t), and Saccharina (542,285 t). Pyropia is economically the most important species in Korea, accounting for up to 68% of total production value. As the top exporter of Pyropia in the world, Korea exported up to US $525 million of Pyropia products to 110 countries in 2018. Other economically important genera include Sargassum, Ulva, Capsosiphon, Codium, and Gracilariopsis, all of which are used for food, and Gelidium, Pachymeniopsis, and Ecklonia which are used as raw material for phycocolloid extraction. Significant work has gone into developing more productive strains of key seaweed species, and in 2012 the Korean government began to certify seaweed varieties. To date, 19 seaweed cultivars have been registered including 13 Pyropia, 5 Undaria, and 1 Saccharina. The industry is now seeking not only to increase productivity but also to add value through processing. Convenience foods and snacks have been developed that target health-conscious consumers and utilize the nutritional properties of seaweeds. The industry is also seeking to promote the sustainability of seaweed farming. One seaweed company in Korea obtained the world's first ASC-MSC (Aquaculture Stewardship Council-Marine Stewardship Council) certification in 2019 and more are expected to follow their lead. With continued research support, the Korean seaweed industry plans to continue to expand to meet new market demands at a sustainable pace.

• ALGAE
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• 제20권2호
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• pp.141-150
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• 2005

To make a preliminary identification of the gracilarioid plant attached to cultivation ropes of Undaria pinnatifida and establish a method of cultivating this plant, the first taxonomic and cultivation studies on this species in Korea were conducted. This gracilarioid plant was identified from its morphological and anatomical features, as Gracilaria chorda. Growth tests using the 10, 20, and 30 cm cuttings of axes of G. chorda were performed twice, from May 3 to August 21, 2002 and from December 15, 2002 to April 3, 2003 in Ihoijin aquafarm, Hoijin, Jangheung, Jeollanamdo, Korea. In the first growing test, the thallus length of the 10, 20, and 30 cm cuttings increased twelve-fold, ten-fold, and seven-fold; the wet weight increased 81-fold, 60-fold, and 41-fold; the numbers of more than 10 cm-long branches increased 3.8-fold, 5.2-fold, and 6.1-fold, respectively. In the second growth test, the thallus length of the 10, 20, and 30 cm cuttings increased seven-fold, 5.5-fold, and four-fold; the wet weight increased 81-fold, 53-fold and 36-fold; the number of branches increased 3.8-fold, 7.3-fold, and 6.6-fold, respectively. The cultivation of G. chorda by vegetative regeneration using cuttings of thallus axes was successful for the first time in Korea.

• Natural Product Sciences
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• 제22권1호
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• pp.25-29
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• 2016

High-performance liquid chromatography was performed in order to analyze the changes in the flavonoid content (rutin, hyperin, afzelin, quercetin, and kaempferol) of Acanthopanax divaricatus and A. koreanum, in response to different cultivation methods (pinching height, planting time, and top dressing). The total flavonoid content of A. divaricatus and A. koreanum ranged from 0.201 to 0.690 mg/g with different pinching heights, 0.143 to 1.001 mg/g for different planting times, and 0.156 to 1.074 mg/g depending on the rate of fertilizer application. In both A. divaricatus and A. koreanum, the total flavonoid content in the upper section of the plant was greater than that in the lower section. These results demonstrate which cultivation methods maximize the flavonoid content of A. divaricatus and A. koreanum, and thus help to optimize flavonoid yields to improve production for nutraceutical, pharmaceutical, and cosmeceutical applications.

• 한국수산과학회지
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• 제50권1호
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• pp.32-40
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• 2017

The aim of this study was to evaluate a temperature-induced two-stage cultivation (TTC) strategy for the regulation of lipid and carbohydrate production by two microalgae, Chlorella vulgaris and Dunaliella salina, for biofuel production. The microalgae were grown under several temperature conditions (15, 25, 35, and $45^{\circ}C$) and optimal growth was observed at $25^{\circ}C$ for both microalgae. To test the TTC, aseptically cultured microalgae were incubated under optimal conditions ($25^{\circ}C$) for 20 days, and then divided into four aliquots that were incubated at 15, 25, 35, and $45^{\circ}C$ for 5 days. Similar but somewhat decreased growth rates were observed at the non-optimal temperatures (15, 35, and $45^{\circ}C$). In addition, while total lipid accumulation increased in a temperature-dependent manner in both microalgae, total carbohydrate increased with temperature in C. vulgaris but decreased in D. salina. However, for lipid and carbohydrate production, while the highest lipid productions of C. vulgaris and D. salina were observed at $25^{\circ}C$ and $35^{\circ}C$, respectively, the highest total carbohydrate productions of C. vulgaris and D. salina were obtained at $15^{\circ}C$ and $25^{\circ}C$, respectively. These results suggest that the TTC strategy may be easily and efficiently applied to bioprocessing for biofuel production.

• 한국미생물·생명공학회지
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• 제29권1호
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• pp.56-61
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• 2001

For the development of probiotics in aquaculture of marine organisms, three strains having psychrophilic and salt tolerant characteristics were isolated from Kimchi. Amng the isolated strains. MG19, MG89 and MG208 were identified as Lactobacillus brevis, Enterococcus faecium and Lactobacillus plantarum, respectively. The neutralized culture broth of isolated strains were tested in order to evaluate the antibactrial activity, 조초 showed high antibacterial activity against Edwardsiella tarda, Vibrio cholerae andPseudomonas fluorescens. In mixed culture of pathogens and isolated strain,pathogens were signifi-cantly inhibited after 2 days of cultivation but the isolated strains showed normal growth. When the Edwardsiella tarda was cultured with three isolated strains, its growth was completely inhibited after 254 hours of cultivation. The effect of isolated three strains as probiotics was investigated based on the changes in body weight of aquacultured flounder. After 50 days feeding trial, it was found that the mean body weight gain of the tested group fed freeze-dried isolated cells was significantly greater than that of the control group. These results suggest that these isolated strains can play an important role as probiotics in aquaculture.

• 한국산학기술학회논문지
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• 제19권8호
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• pp.385-391
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• 2018

전복 양식은 산업 측면에서 단기간에 급성장을 이루어온 반면, 전복의 수급 및 가격 전망에 대한 연구는 많지 않은 편이다. 또한 연구를 통해 개발된 모형도 적합성과 예측력이 낮은 문제점을 안고 있다. 모형상의 문제 해결을 위해서는 전복 치패 입식량, 양성 물량, 출하량 간의 시차 및 연계성을 유지하면서 동시에 기대 가격 변동에 의해 치패가 입식되고, 양성되어 출하되는 생물학적 공급 모형을 구축할 필요가 있다. 본 연구에서는 전체적인 전복 수급전망 모형에서 핵심적인 부분인 전복의 양성 물량 결정 모형 설정을 위해 양성 물량에 영향을 미치는 주요 변수를 확인하고, 이들 변수와 양성 물량 간의 인과 관계를 검증하였다. 양성 물량에는 치패 입식량과 전복 산지 가격을 물미역 가격으로 나눈 전복 상대 가격이 큰 영향을 미치는 것으로 나타났다. 또한 설정된 모형의 적합성 판별을 위해 양성 물량의 실제 관측치와 추정치를 연도별로 비교한 결과 모형의 적합성이 높은 것으로 판명되었다.