• 농약과학회지
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• 제8권2호
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• pp.117-128
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• 2004

농약 등 화학물질의 생태독성평가에서 주요 이용되는 수서무척추동물로 국제적으로 추천하고 있는 물벼룩은 D. magna이다. 하지만 D. magna는 국내에 서식하지 않는 종이므로 우리나라 환경에 적합한 생태 위해성평가를 위해서는 국내에 서식하는 대표종에 대한 독성시험법을 개발할 필요가 있다. 따라서 본 연구는 국내에 서식하는 물벼룩 중에 농업환경에서의 대표종 4종(Daphnia obtusa, Daphnia sp., Moina macrocopa, Simocephalus vetulus)을 선정하여 이들 종에 대한 최적실내사육조건을 확립하고자 3종의 조류를 배양한 후 냉장보관 하면서 먹이의 종류 및 양에 따른 물벼룩의 생육특성을 조사하였다. 그 결과 시험에 사용된 국내산 물벼룩은 국제적인 추천종인 D. magna에 비해 먹이의 양이 절반 정도 수준에서도 잘 생육하는 것으로 조사되었고 특히 Chlorella가 가장 적합한 먹이인 것으로 나타났는데, Chlorella의 최적 투여농도는 $25\times10^4\sim50\times10^4$cells/mL 이었다.

• ALGAE
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• 제35권3호
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• pp.263-275
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• 2020

Water temperature is known to affect the growth and feeding of marine dinoflagellates. Each dinoflagellate species grows well at a certain optimal temperature but dies at very cold and hot temperatures. Thus, changes in water temperatures driven by global warming and extremely high or low temperatures can affect the distribution of dinoflagellates. Yihiella yeosuensis is a mixotrophic dinoflagellate that can feed on only the cryptophyte Teleaulax amphioxeia and the chlorophyte Pyramimonas sp. Furthermore, it grows fast mixotrophically but rarely grows photosynthetically. We explored the direct and indirect effects of water temperature on the growth and ingestion rates of Y. yeosuensis feeding on T. amphioxeia and the growth rates of T. amphioxeia and Pyramimonas sp. under 7 different water temperatures (5-35℃). Both the autotrophic and mixotrophic growth rates of Y. yeosuensis on T. amphioxeia were significantly affected by temperature. Under the mixotrophic and autotrophic conditions, Y. yeosuensis survived at 10-25℃, but died at 5℃ and ≥30℃. The maximum mixotrophic growth rate of Y. yeosuensis on T. amphioxeia (1.16 d^-1) was achieved at 25℃, whereas the maximum autotrophic growth rate (0.16 d^-1) was achieved at 15℃. The maximum ingestion rate of Y. yeosuensis on T. amphioxeia (0.24 ng C predator^-1 d^-1) was achieved at 25℃. The cells of T. amphioxeia survived at 10-25℃, but died at 5 and ≥30℃. The cells of Pyramimonas sp. survived at 5-25℃, but died at 30℃. The maximum growth rate of T. amphioxeia (0.72 d^-1) and Pyramimonas sp. (0.75 d^-1) was achieved at 25℃. The abundance of Y. yeosuensis is expected to be high at 25℃, at which its two prey species have their highest growth rates, whereas Y. yeosuensis is expected to be rare or absent at 5℃ or ≥30℃ at which its two prey species do not survive or grow. Therefore, temperature can directly or indirectly affect the population dynamics and distribution of Y. yeosuensis.

• 한국물환경학회지
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• 제24권3호
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• pp.306-310
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• 2008

Characteristics of microalgal growth was investigated using anaerobic effluent from two-phase animal waste digestor as substrate. Batch experiments were carried out to investigate the effect of the initial nitrogen and phosphorus concentrations on growth of Microcystis aeruginosa, Chlorella sp. and Euglena gracilis. In 400 times diluted anaerobic effluent (TN 3 mg/L), single cell growth of the Euglena gracilis population increased twice without delay, although Chlorella sp. and Microcystis aerugenos take over 144 hours. Similar appearance with single cell growth was observed in mixed cultures. However, microalgae population did not increase under condition of 10 times diluted influent (TP 3 mg/L) in both pure and mixed cultures, which was affected by high organic and nitrogen concentration. Logistic growth model successfully fitted to determine biokinetic parameters such as ${\lambda}$: lag time, ${\mu}m$: maximal specific growth rate, A: asymptote of growth.

• Journal of Plant Biology
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• 제25권3호
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• pp.113-121
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• 1982

The effects of 6 biocides on the growth of Chlamydomonas reinhardii in pure culture were studied. For the batch culture assay of biocides, the growth rate in control tubes should be compared with in the test tubes and the effective concentration calculated on the basis of the percent decrease in growth rate at the different toxicant concentration. The concentrations at which 50% decrease in growth rate was observed are $40{\mu}g$/l for butachlor and $350{\mu}g$/l for alachlor in herbicide, $900{\mu}g$/l for phenazine-5-oxide and $3,400{\mu}g$/l for isoprothiolane in fungicide, and $3,330{\mu}g$/l for fenthion and $332,500{\mu}g$/l for trichlorfon in insecticide. The inhibitory effect on the growth of Chlamydomonas reinhardii by the treatment of various biocide concentrations was decreased in order of herbicide>fungicide>insecticide. Chlorophyll and carotenoid content per cell were increased, whereas chlorophyll a/b ratio was hardly affected by biocides. The effects of biocides on pigment content were also decreased in order of herbicide>fungicide>insecticide, which suggested the relationship between the effect of biocides on the pigment content and inhibition of growth rate.

• 한국수산과학회지
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• 제33권1호
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• pp.32-37
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• 2000

본 연구는 갈색 해조류로부터 추출한 alginate를 사용하여 제조한 Ag-alginate에 대한 최적의 은 첨가량을 구하여 항균성능을 측정하고, 기존의 상품으로 판매되고 있는 항균제의 성능과 비교하였다. 포도상구균과 대장균의 성장은 pH 7에서 가장 활발하였으며, 포도상구균은 pH에 매우 민감하였으나, 대장균은 pH 변화에 대한 저항력을 어느 정도 나타내었다. 포도상구균은 배양 초기에 일정기간의 사장시간 (dead time)이 경과한 후 급격하게 성장하였고, 대장균은 약 20분 이내의 사장시간이 경과한 후 완만하게 성장하였다. 해조류로부터 추출한 alginate를 정제하여 제조한 Ag-alginate의 경우, 포도상구균 및 대장균에 대해서 $0.006\;wt.{\%}$ 은을 첨가한 배양액에서 우수한 항균성능을 나타내었으며, 포도상구균보다 대장균에 대하여 더 강한 항균력을 나타내었다. 그러나 미역 및 다시마로부터 추출한 alginate를 정제하지 않고 제조된 Ag-alginate의 경우, 포도상구균 및 대장균에 대한 항균성능은 현저하게 감소되었다. 국내에서 수입되어 항균섬유용으로 많이 사용되고 있는 Agzeolite계 제품의 항균력과 비교하여도 유사한 항균성능을 나타내고 있으므로 Ag-alginate는 수술용 봉합사, band, gauze, 붕대 등과 같은 의료용 섬유에 사용이 가능하다고 판단된다.

• ALGAE
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• 제23권3호
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• pp.241-250
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• 2008

Since seagrasses in the coastal and estuarine ecosystems achieve high levels of production, they require high inorganic carbon and nutrient incorporation. Thus, seagrasses may play a significant role in carbon and nutrient cycling in the coastal and estuarine ecosystems. To examine growth dynamics of Zostera marina L. environmental factors such as underwater irradiance, water temperature, and salinity, and biological parameters such as shoot density, biomass, shoot morphology, and leaf productivity were measured in two bay systems (Jindong Bay and Gamak Bay) on the southern coast of Korea. While underwater irradiance did not show distinct seasonal trend, water temperature at both sites exhibited clear seasonal trend throughout the experimental period. Shoot density increased dramatically during winter due to the increased seedlings through germination of seeds in Jindong Bay and due to the increased lateral shoots in Gamak Bay. Eelgrass biomass increased during winter and decreased during summer. Maximum biomass in Jindong Bay and Gamak Bay was 250.2 and 232.3 g dry weight m–a2, respectively. Carbon incorporation into the eelgrass leaf tissues was estimated from productivity and leaf tissues carbon content. The calculated annual carbon incorporations at the Jindong Bay and Gamak Bay sites were 163 and 295 g C m–`2 y–`1, respectively. This high carbon incorporation into seagrass tissues suggests that seagrass habitats play an important role as a carbon absorber in the coastal and estuarine ecosystems.

• ALGAE
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• 제35권2호
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• pp.123-131
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• 2020

Sargassum macrocarpum is a rich source of anti-inflammatory compounds. Recently, one of the compounds, tuberatolide B, has been reported as a functional anti-inflammatory additive for foods and nutraceuticals. The artificial seeding, growth and maturation of S. macrocarpum were investigated from May 2018 to September 2019. Indoor culture experiments for induction of egg release were conducted at temperatures of 17, 20, 23, and 26℃ and irradiances of 0, 10, 20, 40, and 80 μmol photons m^-2 s^-1 under 14 : 10 h (L : D) photoperiod. Within a given treatment combination, higher temperatures and irradiance levels favoured the maturation of receptacles in S. macrocarpum. Using artificial temperature and irradiance control, thalli matured one month earlier than thalli in nature. Under natural condition, receptacle formation began in April, and the eggs were released in June and July. The release of eggs from the receptacles was promoted at 17-20℃ and 40-80 μmol photons m^-2 s^-1, and the fastest growth of germlings occuring at 15-17℃ and 40 μmol photons m^-2 s^-1. For mature thalli, 300 g wet-weight was sufficient to seed 100 m of seed string. Thalli grew to 10.5 ± 2.6 cm in length at a density of 6.7 ± 3.3 individuals m^-1 after 1 year of cultivation, from germination. This study demonstrates that it is possible to cultivate S. macrocarpum for the production of anti-inflammatory products.

• 대한환경공학회지
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• 제33권5호
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• pp.314-324
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• 2011

하수를 이용해서 배양된 조류는 바이오디젤 생산에 유용한 자원이다. 그러나 실제 하수에서 조류의 영양염류 신진대사와 하수 세균과의 상호작용에 관한 연구는 미흡하다. 본 연구에서는 하수로 배양되는 대표적 조류균주인 Ankistrodesmus gracilis SAG 278-2에 의한 하수 내 질소, 인 제거 거동을 평가하였고, 조류와 상호작용하는 하수 내의 세균 군집을 분석하였다. 하수 슬러지 세균 군집과 비교하였을 때, 조류-세균 복합 군집은 하수 내보다 높은 영양염류 제거를 보였다. 16S rRNA 유전자 분석 결과, 조류-세균 군집에서 조류가 성장함에 따라 Unclassified Alcaligenaceae 세균이 선택적으로 우점됨을 알 수 있었고, 조류에 의해서 선택적으로 우점화된 하수세균은 자연 수질 환경에서 조류와 공생적으로 상호작용 하는 것으로 알려진 Alcaligenes faecalis subsp. 5659-H와 계통학적으로 가까운 것으로 밝혀졌다. 본 연구의 결과, 하수 내의 높은 영양염류 제거를 보이는 조류-세균 복합 군집에서의 조류의 성장 및 신진대사가 특정 세균의 분포에 영향을 주는 것을 알 수 있었다.

• ALGAE
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• 제37권2호
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• pp.105-121
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• 2022

Modern seaweed farming relies heavily on seedlings from natural beds or vegetative cuttings from previous harvests. However, this farming method has some disadvantages, such as physiological variation in the seed stock and decreased genetic variability, which reduces the growth rate, carrageenan yield, and gel strength of the seaweeds. A new method of seedling production that is sustainable, scalable, and produces a large number of high-quality plantlets is needed to support the seaweed farming industry. Recent use of tissue culture and micropropagation techniques in eucheumatoid seaweed production has yielded promising results in increasing seed supply and growing uniform seedlings in large numbers in a shorter time. Several seaweed species have been successfully cultured and regenerated into new plantlets in laboratories using direct regeneration, callus culture, and protoplast culture. The use of biostimulants and plant growth regulators in culture media increases the seedling quality even further. Seedlings produced by micropropagation grew faster and had better biochemical properties than conventionally cultivated seedlings. Before being transferred to a land-based grow-out system or ocean nets for farming, tissue-cultured seedlings were recommended to undergo an acclimatization process to increase their survival rate. Regular monitoring is needed to prevent disease and pest infestations and grazing by herbivorous fish and turtles during the farming process. The current review discusses recent techniques for producing eucheumatoid and other valuable seaweed farming materials, emphasizing the efficiency of micropropagation and the transition from laboratory culture to cultivation in land-based or open-sea grow-out systems to elucidate optimal conditions for sustainable seaweed production.

• ALGAE
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• 제19권4호
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• pp.293-301
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• 2004

여수해만에서 분리한 Gymnodinium catenatum의 성장에 있어서 최적 수온과 염분 조건을 파악하기 위해 수온 6단계,염분 5단계의 조합에 의한 30단계의 배치배양을 실시하여, 성장속도를 계산하였다. C. catenatum은 약 18${^{\circ}C}$ 이상의 수온과 전 염분단계에서 0.3day$^{-1}$ 이상의 성장속도를 보였으며 수온의 감소와 함께 성장속도도 감소하였다. 하지만 염분은 성장에 그다지 영향을 미치지 않았다. 최대성장속도(0.5day$^{-1}$)는 수온 25${^{\circ}C}$와 염분 30psu에서 얻어졌다. 따라서, 수온과 염분에 따른 성장속도를 고려할 때, C. catenatum은 이른 여름부터 가을까지 한국남해연안해역에서 서식 가능한 것으로 판단된다 이 종의 출현을 예측하기 위한 모델식은 $\mu$ = 0.005-T$^2$ - 0.0001164 T$^3$ - 0.063-S + 0.005-S$^2$ - 0.00007608-S$^3$ - 0.003-T-S + 0.00005308-T$^2$-S로 나타났다. 한편. 수온 18${^{\circ}C}$와 염분 30psu 조건하에서 6단계의 광도 실험을 실시한 결과, 광량에 따른 C. catenatum의 성장은 $\mu$ = 0.16 (I - 10.4)/(1+21.8), (r=0.96)의 관계식으로 Ks는 42.6$\mu$mol m$^{-2}$s$^{-1}$, I$_0$는 10.4$\mu$mol m$^{-2}$s$^{-1}$이었다. 따라서 수온, 염분과 광 조건만을 고려할 경우 C. catenatum은 고수온기 한국 남해 내만과 연안해역에서 우점종으로 출현할 가능성이 높을 것으로 판단되었다.