• 한국수산과학회지
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• 제33권3호
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• pp.225-229
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• 2000

담수산 rotifer, B. calycinoms를 대상으로 5 종류의 먹이 (ESP, 담수산 농축 Chlonlla, 빵효모 단독구와 $ESP 70{\%}와 담수산 농축 Chlorella 30{\%} 혼합구 및 빵효모 30{\%}와 담수산 농축 Chlorella 70{\%}$ 혼합구)에 대한 내구란 생산과 먹이종류에 따라 생산된 내구란의 부화율을 조사하였다. 먹이 종류에 따른 내구란 생산은 $ESP 70{\%}$와 담수산 농축 Chlorella 30{\%}$ 혼합구와 빵효모 30{\%}$와 담수산 농축 Chlorells 70{\%}$ 혼합구에서 각각 123.3 개/ml와 126.7 개/ml로 가장 높게 나타났고, 단독구보다 혼합구에서 높게 나타났다. 또한 먹이에 따른 내구란의 부화율은 $ESP 70{\%}$와 담수산 농축 Chlorella $30{\%}$ 혼합구에서 $71.9{\%}$로 가장 높았지만 빵효모 $30{\%}$와 담수산 농축 Chlonlla $70{\%}$ 혼합구 및 담수산 농축 Chlorella 단독구와는 유의적인 차이는 보이지 않았다. 본 연구 결과, 담수산 rotifer의 내구란 생산 및 부화율을 높이기 위한 먹이로 담수산 농축 Chlorella에 빵효모와 ESP를 혼합하여 공급하는 것이 가장 효과적인 것으로 판단된다.

• 한국수산과학회지
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• 제36권6호
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• pp.606-613
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• 2003

This study investigated the effects of food type (condensed freshwater Chlorella, dried Chlorella, dried Spirulina, dried Schizochytrium, baker's yeast and $\omega-yeast$) and amount, and supplementation of vitamin $B_{12}$ on the growth of freshwater rotifer (Brachionus calyciflorus) in high density culture. Growth of rotifers fed condensed freshwater Chlorella was the highest and its density ranged $7.65-8.14{\times}10^3\;inds./mL.$ The primary lipid acids of rotifers fed condensed freshwater Chloyella were linoleic and linolenic, and their amount ($\%$ of total fatty acids) were $48.8\%\;and\;26.8\%,$ respectively. This suggests that condensed freshwater Chlorella would be an effective diet for high quality and quantity rotifers, which in turn serve as live food for freshwater fish larvae. Growth rate of rotifers with Chlorella supplementation increased as amount of supplementation increased up to 1.5 and 2.5 mg at 28 and $32^{\circ}C$, respectively. However, undissolved ammonia toxicity and packing volume of Chlorella in culture medium, reached the optimal conditions for the stable and effective cultivation of rotifers when amount of condensed freshwater Chlorella was 1.5 mg in dry weight per 1,000 rotifers at $28^{\circ}C\;and\;32^{\circ}C$ Growth of rotifers in condensed freshwater Chlorella with vitamin $B_{12}$ supplementation was significantly higher than that of rotifers without supplementation. However, no significant difference was found among the different concentrations of vitamin $B_{12}.$ Therefore, vitamin $B_{12}$ could improve the growth of rotifers (B. calyciflorus).

• 한국수산과학회지
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• 제32권3호
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• pp.280-283
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• 1999

고밀도 배양에 있어서 먹이종류 (해수 Chlorella, 담수 Chlorella, 유지효모)에 따른 Rotifer, Brachionus rotundiformis 성장과 영양가를 조사하기 위해서 10$\ell$ 배양수조에서 실험을 실시하였다. 해수 Chlorella, 담수 Chlorella와 유지효모를 공급한 rotifer의 최고밀도는 각각 10,900$\~$12,400개체/ml, 9,190$\~$10,600개체/ml, 2,390$\~$2,750개체/ml, 였다. 따라서 해수 Chlorella, 담수 Chlorella를 공급한 rotifer의 최고밀도는 유지효모를 공급한 rotifer보다 높게 나타났다. 또한 해수 Chlorella를 공급한 rotifer의 고도불포화지방산 함량은 $8.71\%$로 나타났다. 이 것은 유지효모를 공급한 rotifer ($9.14\%$)와 비슷한 경향을 보였지만, 담수 Chlorella를 공급한 rotifer ($4.45\%$)보다는 높게 나타났다. 따라서 본 연구의 결과를 종합해 보면 고밀도 rotifer 배양에 있어서 양질의 rotifer를 생산하기 위해서 해수 Chlorella가 적절한 먹이인 것을 판단된다.

• 한국양식학회지
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• 제1권2호
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• pp.135-143
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• 1988

해산어류 및 갑각류의 유생사육시 먹이로 사용되는 rotifer(Brachionus Plicatilis)의 먹이생물로 이용되는 Chlorella중 어떤종이 대량사육에 가장 적합한가를 파악하기 위하여 해수산 Chlorella 2종, 담수산 Chlorella 4종에 대한 성장 및 영양염분석의 결과를 요약하면 다음과 같다. 1. 해수산 Chlorella중에서는 C. ellipsoidea가 f/2배지에서 가장 높은 성장을 나타냈고 담수산 Chlorella 중에서는 C. vulgaris가 Complesal에서 가장 높은 성장을 보였다. 2. 성장의 측면에서 볼 때 담수산인 C. vulgaris는 해수산인 C. ellipsoidea보다 specific growth rate가 1.68배나 높게 나타났다. 3. 영양염의 측면에서 볼 때 지방은 해수산인 C. ellipsoidea가 조단백과 회분은 담수산인 C. vulgaris가 더 높았다. 아미노산측정에서 $NH_3$의 함량이 담수산인 C. vulgaris가 해수산인 C. ellipsoidea보다 8배 이상 높은 점이 특이하였다.

• 한국수산과학회지
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• 제33권2호
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• pp.93-97
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• 2000

본 연구는 먹이종류에 따라 고밀도로 배양한 rotifer를 넙치 자어에게 공급하였을 때 이들의 먹이효율을 조사하였다. Rotifer 고밀도 배양의 실험구 먹이는 18 시간 동안 담수산 Chlorella를 공급한 후 6시간 유지효모 및 $Marine\;{\alpha}$를 공급한 것과 24시간 동안 담수산 농축 Chlorella 및 해수산 농축 Chlorella를 공급한 것으로 하였다. 배양수조는 $2l$를 이용하였고 수온 $28{\circ}C$를 유지하였다. $Marine {\alpha}$와 해수산 농축 Chlorella를 공급한 실험구의 n-3 HUFA 함량이 유지효모와 담수산 농축 Chlorella를 공급한 실험구보다 높게 나타났다. 따라서 $Marine\;{\alpha}$와 해수산 농축 Chlorella를 공급한 실험구가 유지효모와 담수산 농축 Chlorella를 공급한 실험구보다 넙치 자어의 성장과 생존률이 높게 나타났다. 또한 $Marine\;{\alpha}$로 배양된 rotifer를 섭취한 넙치 자어 자체의 지방산 중 n-3 HUFA비율이 다른 먹이보다 높게 나타났지만 안정적 배양은 이루어지지 않았다. 따라서 본 실험을 통해서 rotifer 고밀도 배양시 안정적인 rotifer 성장과 rotifer의 질적 개선을 위해서는 24시간 해수산 농축 Chlorella를 공급하는 것이 효율적이며 이들을 넙치 자어에게 공급하였을 때 가장 적절한 먹이일 것으로 판단된다.

• 한국환경과학회지
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• 제24권12호
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• pp.1591-1600
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• 2015

The response of the freshwater microalga, Chlorella vulgaris, to heavy metal stress was examined based on chlorophyll fluorescence analysis to assess the toxic effects of heavy metals in freshwater ecosystems. When toxic effects were analyzed using regular chlorophyll fluorescence analysis, photosystem II activity($F_v/F_m$) decreased significantly when exposed to $Cu^{2+}$ and $Hg^{2+}$ for 12 h, and decreased in the order of $Hg^{2+}>Cu^{2+}>Cd^{2+}>Ni^{2+}$ when exposed for 24h. The effective photochemical quantum yield(${\phi}{\prime}_{PSII}$), chlorophyll fluorescence decrease ratio($R_{Fd}$), minimal fluorescence yield($F_o$), and non-photochemical quenching(NPQ), but not photochemical quenching(qP), responded sensitively to $Hg^{2+}$, $Cu^{2+}$, and $Cd^{2+}$. These results suggest that $F_v/F_m$, as well as ${\phi}{\prime}_{PSII}$, $R_{Fd}$, $F_o$, and NPQ could be used to assess the effects of heavy metal ions in freshwater ecosystems. However, because many types of heavy metal ions and toxic compounds co-occur under natural conditions, it is difficult to assess heavy metal toxicity in freshwater ecosystems. When Chlorella was exposed to heavy metal ions for 12 or 24h, $F_v/F_m$ and maximal fluorescence yield($F_m$) changed in response to $Hg^{2+}$ and $Cu^{2+}$ based on image analysis. However, assessing quantitatively the toxic effects of several heavy metal ions is challenging.

• 한국수산과학회지
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• 제37권1호
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• pp.7-12
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• 2004

This study investigated the possibility of salinity acclimation of freshwater rotifers (Brachionus calyciflorus) as live food for sweetfish (Plecoglossus altivelis) larvae, and also examined the optimal salinity for the growth of sweetfish. Freshwater rotifers cultured in 0 and 4 PSU and seawater rotifers (B. rotundiformis) cultured in 33 PSU were supplied to the larvae with four kinds of enrichment material (condensed freshwater Chlorella, $\omega-yeast,$ baker's yeast, Super Selco) and larval growth at 4 PSU was examined. Growth of the freshwater rotifers positively increased from 0 PSU to 6 PSU, but decreased when over 8 PSU was reached. Growth and survival of the sweet fish larvae reared in 0 PSU were significantly lower than those reared in either 4 PSU or 33 PSU. This indicated that the freshwater rotifers (B. calyciflorus) could be used as live food for sweetfish larvae reared in 4 PSU. The body weight of sweetfish larvae fed on freshwater rotifers enriched with Super Selco was the highest at 0.163 mg, but there was no significant difference in survival and body length of the fish fed with the other enrichment materials. The content of n-3 HUFA of the sweetfish larvae fed on the freshwater rotifers enriched with Super Selco and the condensed freshwater Chlorella was higher than that enriched with $\omega-yeast$ and baker's yeast. These results indicated that B. calyciflorus cultured with the condensed freshwater Chlorella could be used for the sweetfish larvae without enrichment, and the most efficient enrichment material for B. calyciflorus is Super Selco.

• 한국양식학회지
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• 제13권2호
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• pp.147-152
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• 2000

본 연구는 담수산 rotifer, Brachionus calyciflorus의 경제적인 대량배양을 위해서 담수산 농축 ChloreIla와 빵효모 혼합 공급 비율에 따른 효과를 조사하였다. 담수산 rotifer의 최고밀도와 성장은 Chlorella 공급 비율이 높을수록 빠르게 나타났다. Rotifer 밀도가 증가할 수록 배양수의 용존산소량은 감소하였고 이온화 되지 않은 암모니아량도 증가하였다. 특히, Chlorella 100% 단독구에서 용존산소량이 0.2~0.3 ppm으로 낮아지고 이온화되지 않은 암모니아가 14.1~29.6 ppm으로 급격히 증가함에 따라 rotifer 밀도는 급격히 감소하는 경향을 보였다. 따라서 담수산 rotifer를 안정적으로 대량배양하기 위해서는 용존산소가 0.3 ppm이상, 이온화되지 않은 암모니아가 14 ppm 이하로 유지하여야 할 것으로 판단된다. 먹이의 공급 비율에 따른 rotifer의 생산비는 ChloreIla단독구에서 가장 높았다. 그러나 Chlorella 70%와 빵효모 30%를 혼합 공급하면 rotifer 최고밀도에 있어서 Chlorella 단독구와 유의적인 차이가 나타나지 않으면서 Chlorella 100%단독구보다 생산비가 1.8배 낮기 때문에 Chlorella 70%와 빵효모 30%를 혼합 공급하는 것이 가장 경제적이고 안정적인 먹이비율인 것으로 판단된다.

• The Plant Pathology Journal
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• 제34권6호
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• pp.567-574
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• 2018

This study was conducted to investigate the efficacy of freshwater alga, Chlorella fusca on the improvement of growth and qualities in organic spinach and Chinese chives farm. The average height of Chinese chives treated with the chlorella was 3.7 cm smaller than that of the untreated. The leaf width and fresh weight of Chinese chives treated with the chlorella was 0.5 mm wider and 30.3 g heavier than that of the untreated. The commercialization and yield of Chinese chives treated with the chlorella was 11.9% and 18.3%, respectively higher than that of the untreated. Also, the disease severity of gray mold disease of Chinese chives treated with the chlorella was reduced by more than 24.2% when compared with the untreated. The thickness and number of spinach leaves treated with chlorella was 27.9% and 41.8%, respectively higher than that of the untreated. The fresh weight and yield of the spinach treated with the chlorella was 63.6% and 31.5%, respectively higher than that of the untreated. Moreover, the mineral content of K, Ca, Mg, P, Fe, and Mn were recorded higher in the spinach treated with chlorella compared with that of untreated. The results indicated that the freshwater alga, Chlorella fusca is efficient and economical biostimulant in improving plant growth and quality of Chinese chives and spinach in organic farm.

• 한국수산과학회지
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• 제45권2호
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• pp.146-153
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• 2012

This study examined the effect of formulated diets (composed of condensed freshwater $Chlorella$ or $Schizochytrium$ sp., $Crypthecodinium$ sp., and EPA oil sources derived from baker's yeast) on the population growth and fatty acid composition of the brackish water flea ($Diaphanosoma$ $celebensis$) to determine diet effectiveness for mass production. Results indicated that the highest maximum density, fecundity, and population specific growth rate (SGR) of the flea were observed using a diet of $Tetraselmis$ $suecica$ (control). However, results using condensed freshwater $Chlorella$ and the mixed treatment of $Schizochytrium$ sp.+$Crypthecodinium$ sp.+EPA oil did not significantly differ from the control treatment ($P$>0.05). Thus, $T.$ $suecica$ could be replaced with a combination diet of $Schizochytrium$ sp., $Crypthecodinium$ sp., and EPA oil in condensed freshwater $Chlorella$ without growth interruption of $D.$ $celebensis$. As the percentage of combination diet (mix of $Schizochytrium$ sp., $Crypthecodinium$ sp., and EPA oil) in condensed freshwater $Chlorella$ increased, the level of ARA, EPA, DHA, and n-3 HUFA in $D.$ $celebensis$ also increased. However, the population density of $D.$ $celebensis$ sharply decreased with the use of treated supplements C5M5 (CHL [50%] and $Crypthecodinium$ sp.+ $Schizochytrium$ sp. + EPA oil [MIX 50%]). The optimum proportions of CHL and MIX for $D.$ $celebensis$ within the mixture were 70% and 30%, respectively. Based on the results, the combination of $Schizochytrium$ sp., $Crypthecodinium$ sp., and EPA oil in condensed freshwater $Chlorella$ appears to be a stable and effective food source for mass production of $D.$ $celebensis$.