• Journal of Marine Bioscience and Biotechnology
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• v.4 no.1
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• pp.6-10
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• 2010

Indonesia is well-known as biggest producer of seaweed especially for Eucheuma and Gracilaria and also has huge potential resources and capability to develop seaweed cultivation and product. There are several provinces which have potential resources and have been contributing on seaweed production. The next challenge about seaweed production is using integrated system on brackishwater and marine aquaculture. Furthermore, about 2,000,000 ton of potential seaweed production is not explored yet. This article also tries to figure out some related aspects which are technical, economical and forecasting aspect. There is a disease which named "ice-ice" is one of the main problem and giving a new challenge in developing of problem solving for seaweed cultivation method. Economical parameters are also main important key to find out the feasibility of seaweed cultivation industry. In addition, the seaweed cultivation and production in Indonesia also have potential performance on biofuel resources as a part for solving the world problem on energy demand.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.43 no.6
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• pp.589-597
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• 2010

Monthly changes in the proximate and fatty acid compositions of chub mackerel (Scomber japonicus) muscle during cultivation from October 2007 to September 2008 were investigated. The lipid content increased gradually from the first stage of cultivation until March 2008 and then dramatically until May, before decreasing. The highest lipid content during cultivation was 21.6% in May, just before the fish spawns. There was a negative correlation (y=-1.1585x+87.741, $R^2$=0.9495) between the lipid and moisture contents during cultivation of chub mackerel. By contrast, the protein ($18.6{\pm}1.05%$) and ash ($1.18{\pm}0.11%$) contents were essentially unchanged during cultivation. Prominent fatty acids in chub mackerel muscle were 16:0, 18:0, 14:0 saturates, 18:1n-9, 16:1n-7, 18:1n-7 monoenes, and 22:6n-3 (docosahexaenoic acid, DHA), 20:5n-3 (eicosapentaenoic acid, EPA), and 18:2n-6 polyenes. The percentages of n-3 polyunsaturated fatty acids (PUFA), such as DHA and EPA, were higher during three months in the early stage of cultivation than they were subsequently. However, the PUFA (DHA+EPA) content (in mg/100 g of muscle) was lower in the early stage (740-796 mg/100 g muscle) than in the other stages. The highest PUFA (DHA+EPA) content was from April to May (2,749-2751 mg/100 g muscle). The PUFA content was positively correlated with the total lipid content of chub mackerel muscle during cultivation. The results indicate that cultured chub mackerel is a very good source of n-3 PUFA, such as DHA and EPA.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.32 no.3
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• pp.280-283
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• 1999

The experiment was carried out in a 10 $\ell$ vessel in order to evaluate the growth and nutritional quality of rotifer, Brachienus rotundiformis fed by different diets (Freshwater Chlorella, Marine Chlorella and $\omega$-yeast) for the high density cultivation. The maximum densities for the rotifer fed on the marine Chlorella, freshwater Chlorella and $\omega$-yeast were $10,900\~12,400,\;9,190\~10,600$ and 2,390$\~$2,750 inds./ml, respectively. Therefore, the maximum densities for the rotifer fed on the marine Chlorella and freshwater Chlorella were higher than that for rotifer fed on the $\omega$-yeast The essential n-3 highly unsaturated fatty acid in rotifer fed on the marine Chlorella was $8.71\%$ which was slightly lower than that in rotifer fed on the $\omega$-yeast, $9.14\%$, while it was higher than that in the rotifer fed on freshwater Chlorella, $4.45\%$. This result indicated that marine Chlorella could be appropriate diet for the high density cultivation of rotifer.

• Journal of Marine Bioscience and Biotechnology
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• v.11 no.1
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• pp.23-28
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• 2019

For successful microalgal biodiesel production, the strain should be selected carefully. Fast growth rate and high fatty acid contents are desired traits for algal biodiesel production. In ocean cultivation of microalgae, seawater temperature slowly changes over seasons, and rotating algal strains in accordance with their optimal temperature could improve overall productivity. Additionally, use of indigenous strain is preferred to alleviate potential impacts on the environment. In this study, five strains of Tetraselmis sp. from nearshore of Youngheung Island, Incheon, Korea, were isolated during winter and characterized for their growth patterns and fatty acid compositions in the low temperatures ($5-15^{\circ}C$). The five strains showed various characteristics in optimal growth temperature, fatty acid contents, and compositions. Compared with a strain of Tetraselmis sp., isolated from Ganghwa island in a previous study, a rapid-growing strain with 237% higher biomass productivity and an oleaginous strain with twice higher fatty acid contents at $10^{\circ}C$ were isolated. The oleaginous Tetraselmis strain showed the highest fatty acid productivity among the strains, having 438% higher productivity than the previous strain. Using the new isolates in the seasons with low seawater temperature would improve microalgal fatty acid productivity in ocean cultivation.

• Proceedings of the Korean Society for Applied Microbiology Conference
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• 2004.06a
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• pp.117-123
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• 2004

• Journal of Marine Bioscience and Biotechnology
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• v.6 no.2
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• pp.118-122
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• 2014

The ocean provide great benefits for microalgal mass cultures with maintaining stable temperature due to high specific heat, mixing by wave energy, and providing large area for large-scale microalgae cultures. In this study, we cultivated a marine green microalga, Tetraselmis sp. KCTC12432BP, using marine photobioreactors on the ocean for investigating the effect of $NaHCO_3$ concentration on the biomass productivities and evaluating the potential of ocean microalgae culture. The culture medium consist of three fold concentrated f/2-Si with 4 g/L of $NaHCO_3$, which is dissolved in natural seawater. After 11 days of cultivation, the cultures reached stationary phase at biomass concentration of 1.6 g/L. At that time, $NaHCO_3$ concentration of 0, 2, and 4 g/L were fed to the cultures. The daily productivities of 0.11, 0.19, 0.30 g/L/day were attained with feeding rate of 0, 2, and 4 g/L $NaHCO_3$, respectively. Biomass productivity of Tetraselmis sp. KCTC12432BP was a function of the $NaHCO_3$ feeding rate as expected. This research shows that the microalgae can grow with $NaHCO_3$ as carbon source in marine photobioreactors on the ocean while exploiting various benefits of ocean cultivation.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2002.05a
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• pp.450-452
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• 2002

• Journal of Marine Bioscience and Biotechnology
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• v.9 no.1
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• pp.14-21
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• 2017

The purpose of this study was to inhibit biofouling on a selectively permeable membrane (SPM) and increase biomass productivity in marine photobioreactors (PBRs) for microalgal cultivation by chemical treatment. Surfaces of a SPM, composed of polyethylene terephthalate (PET), was sulfonated to decrease hydrophobicity through attaching negatively charged sulfonic groups. Reaction time of sulfonation was varied from 0 min to 60 min. As the reaction time increased, the water contact angle value of SPM surface was decreased from $75.5^{\circ}$ to $44.5^{\circ}$, indicating decrease of surface hydrophobicity. Furthermore, the water permeability of sulfonated SPM was increased from $5.42mL/m^2/s$ to $10.58mL/m^2/s$, which reflects higher nutrients transfer rates through the membranes, due to decreased hydrophobicity. When cultivating Tetraselmis sp. using 100-mL floating PBRs with sulfonated SPMs, biomass productivity was improved by 34% compared with the control group (non-reacted SPMs). In addition, scanning electron microscopic observation of SPMs used for cultivation clearly revealed lower degree of cell attachment on the sulfonated SPMs. These results suggest that sulfornation of a PET SPM could improve microalgal biomass productivity by increasing nutrients transfer rates and inhibiting biofouling by algal cells.

• Journal of Marine Bioscience and Biotechnology
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• v.10 no.2
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• pp.91-96
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• 2018

There are many eutrophic lakes by point and non-point pollution sources such as in dustrial waste water, domestic raw sewage, and mucks. The eutrophic lakes not only cause algal blooms but also destroy the ecosystem in the lakes due to high nutrient concentrations. The purpose of this study was to improve water quality in eutrophic lakes by cultivating microalgae using photobioreactors (PBRs) with selectively permeable mesh (SPM), supplying nutrients in the lake and inhibiting cell leakage by diffusion and water permeability. Chlorella vulgaris, was cultivated using PBRs with SPM installed in Inkyung Lake located in Inha university, Incheon, Korea. When cultivating C. vulgaris, $8.3g/m^2/day$ of average biomass productivity was obtained at 3 days. Furthermore, concentrations of total nitrogen and phosphorus were reduced by 35.7% and 84.2%, respectively, compared to initial condition and water quality in eutrophic lake was improved to oligotrophic environment. These results suggest that microalgal cultivation using PBRs with SPM in the lake could produce microalgal biomass as well as improve water quality by decreasing nutrient concentrations.

• Fisheries and Aquatic Sciences
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• v.27 no.5
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• pp.283-293
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• 2024

Mahseer (Tor soro) growth performance tends to be slow, necessitating further development and intensification of cultivation. One way to develop aquaculture intensification is to manipulate cultivation containers to create optimal environmental conditions for the mahseer to grow. This study aimed to examine the body performance and growth performance of mahseer reared in different colored containers. Experimental research with completely randomized design was employed, with four colored container treatments namely treatment A (transparent), B (green), C (blue), and D (black), with four replications in each treatment. Findings indicate that different rearing media colors had significant effect on absolute length (4.68 ± 0.24 cm), absolute weight (1.58 ± 0.35 g), specific growth rate (2.17 ± 0.38%), feed conversion ratio (2.87 ± 0.04), survival rate (100 ± 0.00%), gross energy (3,816 ± 65.05 cal/g), and body proximate. Physiologically, mahseer fish bred using blue and black containers tend to be more resistant to stress.The best body performance and growth performance were observed in the blue and black colored containers.