• 한국해양바이오학회지
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• 제14권1호
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• pp.1-8
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• 2022

This study examined the growth, fatty acid (FA) content, and carotenoids of a newly isolated freshwater microalga, Mychonastes sp. 246, in various culture media. The appropriate temperature and light intensity for culturing Mychonastes sp. 246 were determined as 18℃-22℃ and 200-250 µmol/m²/s using a high throughput photobioreactor. The microalgal cells were cultivated in 0.5 L bubble column photobioreactors using BG11, Bold's Basal media, and f/2 media. According to the growth results of the microalgae, BG11, among the tested media, showed the highest biomass concentrations (3.5 ± 0.1 g/L in 10 d). To enhance the biomass growth of the microalgae, the N:P ratio in BG11 was manipulated from 45:1 to 7:1 based on the stoichiometric cell composition. The biomass concentrations of Mychonastes sp. 246 grown on the manipulated BG11 (MBG) increased to 38% (4.6 ± 0.3 g/L in d) compared with the original BG11 (3.3 g/L). The FA content of the microalgae grown on the MBG was lower (8.4%) than that of the original BG11 (10.1%) while the FA compositions did not exhibit any significant differences. Furthermore, three kinds of carotenoids were identified in Mychonastes sp. 246, zeaxanthin, lutein, and β-carotene. These results suggest an effective strategy for increasing biomass concentrations, FA content, and carotenoids of microalgae by performing a simple N:P adjustment in the culture media.

• 환경위생공학
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• 제15권1호
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• pp.39-45
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• 2000

The purpose of this study was conducted to indentified the fixing quality of $CO_2$, the most important greenhouse effect gas, by microalgae Chlorella ellipsoidea in batch test apparatus. The glass flask of $1.4{\ell}$ culture media which was saturated with 99.99% pure $CO_2$ gas was setted water bath of $25^{\circ}C$, 5000Lux, and seeded 100$m\ell$ algae liquid. We checked the change of inorganic carbon concentration and algae population with time in culture media. The result were next: the growth of algae population relied on aquatic IC(inorganic carbon) concentration. And the pH was increased with decrease of IC concentration. The growth of algae population had positive correalation with $CO_2$ concentration, and the coefficient of correlation was 0.982. The specific growth rate($\mu$) of Chlorella ellipsoidea was 1.104/d, the maximum specific growth $rate({\mu}_{max}$) of 9.21/d, and helf velocity constant($K_s$) of $259mg/{\ell}$ by Monod equation.

• 한국어업기술학회:학술대회논문집
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• 한국어업기술학회 2001년도 춘계 수산관련학회 공동학술대회발표요지집
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• pp.201-202
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• 2001

Mass culture of microalgae as feed for mollusc, crustaceans and fish is an important components of the mariculture industry (Metting Jr., 1996) Growth activator for tetraselmis suecica were screened in methanol and water soluble extracts of several seaweed tissues. Also examined in this study were change in growth rate, biochemical composition, and digestion efficiency, of T.suecica cultured with and without the most effective of these extracts, the water soluble component extracted form M. nitidium. (omitted)

• 한국해양학회지:바다
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• 제15권1호
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• pp.1-7
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• 2010

본 연구에서는 자연혼합배양(nature mixed culture)이라는 기법을 이용하여 해수관상어를 사육하는데 성공하였고 자연혼합배양수조에서 해수관상어의 자어는 정상적으로 성장하고 생존 가능하였다. 자연혼합배양수조에 출현한 플랑크톤성 미소생물은 모두 34종이었으며 그 중에는 Detonula pumila, Nitzschia sp., Fragilaria oceanica, Chaetoceros curvisetus, Stephanodiscus sp., Chaetoceros decipiens, Chaetoceros sp., Thalassiosira rotula, Eucampia zodiacus, Diploneis splendica, Nitzschia longissima, Surirella cuneata, Asterionella glacialis, Nitzschia spp., Chaetoceros debile, Thalassionema nitzschioides, Nitzschia, closterium, Skletonema costatum과 Licmophora sp와 같은 규조류가 19종, Euglena sp, Gonyaulax sp., Pyramimonas sp., Protoperidinium sp., Eutreptia, sp., Parapedinella sp., unidentified micro-flagellate, Gyrodinium sp., Scrippsiella trochoidea, Gymnodinium sanguineum, Chrysochromulina sp., Gymnodinium sp., Prorocentrum triestinum과 Micromonas sp.와 같은 편모조류가 14종 그리고 1종의 섬모충으로서 Mesodinium rubrum가 관찰되었다. 한편, 미소생물 종 중에서 편모조류의 한종인 Chrysochromulina sp.는 사육기간 동안 우점하였는데 이와 같은 결과는 배양 개시 후 10일째부터 지속적이고 안정적으로 유지 가능하였다.

• 공업화학
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• 제21권6호
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• pp.659-663
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• 2010

미세조류는 전 세계 바다에 분포하고 있으며 일부 종들은 인간의 식품에 이용되어 왔다. 특히, 광합성 미세조류 Nannochloropsis oculata는 영양적 가치가 우수하여 관심을 받고 있다. 본 연구에서는 광합성 미세조류 Nannochloropsis oculata의 고농도배양을 위한 배양온도, 초기 pH, 배양액 선정, 인공해수 농도, 배지농도, $CO_2$영향 등 최적조건을 확립하고자 하였다. 그 결과, 3%의 인공해수, 초기 pH 8.5, 배양온도 $25^{\circ}C$가 최적 배양조건으로 판별되었다. 미세조류에 $CO_2$를 공급하지 않았을 때에는 건조 균체량이 0.76 g/L이었지만, 5% $CO_2$ 공급 이후 1.50 g/L로 높은 성장률을 보였다. 클로로필 생합성은 미세조류 성장과 깊은 연관이 있는 것으로 판명되었다.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2012년도 추계학술대회 논문집
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• pp.953-954
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• 2012

• 유기물자원화
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• 제23권1호
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• pp.38-44
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• 2015

본 연구에서는 저온 해양성 미세조류인 Nannochloropsis sp.를 대상으로 (주)아이엠비즈에서 개발한 수직형 고효율 광배양기를 통한 생산성 평가를 목적으로 2톤의 배양액으로 자가영양의 옥외생장실험을 진행하였다. 한달간 진행된 실험에서, 0.1%의 $CO_2$를 주입한 배양에서는 일평균 0.953g/L의 생산성을 나타냈으며, 공기만을 주입했을 경우에는 0.574g/L의 생산성을 나타냈다. 온도의 분포는 최저 $20^{\circ}C$에서 최고 $31^{\circ}C$에 이르렀으며, 이 범위에서 온도에 따른 생산성의 변화는 크게 차이가 없는 것으로 나타났다. 빛의 세기는 최저 5,000럭스에서 최고 4만 럭스 내외로 조사되었으며, 빛의 세기와 미세조류의 생장사이에 매우 밀접한 관련이 있는 것으로 밝혀졌다. 한편, 본 실험에서 시도된 개발된 배양기를 통한 가압부상에 의한 조류의 수확방법은 효과가 매우 높은 것으로 나타났다.

• 한국수산과학회지
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• 제43권6호
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• pp.654-658
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• 2010

The purpose of this study is to establish methods for enhancing the survival and growth of cold-water fish and crustacean larvae based on the nutritional components of zoo and phyto live foods. Rotifers, Brachionus rotundiformis, were cultured with a supplement of freshwater condensed Chlorella vulgaris at $28^{\circ}C$ and enriched with Algamac $2000^{(R)}$ at 16, 20 and $26^{\circ}C$, respectively. Isochrysis galbana, Chaetoceros calcitrans and Chlorella ellipsoidea were centrifuged for component analysis after being cultured for approximately one week with conway medium at $20^{\circ}C$. The crude protein and lipid contents of the rotifers were 58.4% and 10.9%, respectively, before enrichment. After enrichment at each temperature, total protein and essential amino acid contents were increased by reducing the enrichment temperature. However, unsaturated fatty acids and multiple fatty acid index (UI) showed their highest values at $20^{\circ}C$. Mono-unsaturated fatty acid content was highest (72.6%) at $16^{\circ}C$. The total protein contents of C. calcitrans and C. ellipsoidea were higher, 33.0% and 35.2%, respectively, than that of I. galbana, 27.8%. Methionin, leusine and histidine, essential amino acids of C. ellipsoidea, had considerably higher values, 50.2, 287.2 and 68.1 mg/g dry matter, respectively, compared to other microalgae. Total lipids, UI, DHA and n-3 PUFA of I. galbana had higher values, 23.6, 272.0, 12.9% and 45.2%, respectively, than other microalgae. Therefore, for cold-water fish and crustacean larvae that require high n-3 PUFA and DHA contents, enrichment of rotifers is desirable at $20^{\circ}C$. Fish larvae would also need more I. galbana than other microalgae.

• 한국해양바이오학회지
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• 제6권2호
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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.

• 한국해양바이오학회지
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• 제11권2호
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• pp.81-88
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• 2019

In this study, effects of nitrogen (N) and phosphorus (P) starvation on the cell growth and fatty acid (FA) production of newly isolated freshwater microalgae were investigated. The microalgae were identified as Chlorella sp. and Parachlorella sp. through 18S rRNA sequencing. Optimal culture temperature and light intensity were investigated using a high-throughput photobioreator, and the result was validated in 0.5 L bubble column photobioreactors using BG-11 without NaNO₃ and/or K₂HPO₄. Under nutrient starvation conditions, total FA contents of the microalgae were significantly changed rather than FA composition. Starvation of both N and P was most effective for increasing FA contents in Parachlorella sp (24.4±0.1%) whereas highest FA contents (42.6±1.8%) was achieved when only P was starved in Chlorella sp. among tested conditions. These results suggest an effective strategy for increasing FA production from microalgae using appropriate nutrient starvation.