• Environmental Engineering Research
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• 제20권4호
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• pp.377-382
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• 2015

The high concentration of nitrogen and phosphorus in wastewater incorporated with the ability to use carbon dioxide as the carbon source make the microalgae become more attractive in wastewater treatment process. This study evaluates the optimal conditions for the digestion of settelable solids from the recirculating aquaculture system to produce the biomass of the green microalga Scenedesmus sp. After solids separation, aerobic digestion of settleable solids under disperse condition produced nitrate as the final product of consequently ammonification and nitrification processes. With the optimal digestion procedure, nitrate concentration during aerobic digestion in 2000 mL vessel increased from $9.63{\pm}0.65mg\;N/L$ to $58.66{\pm}0.06mg\;N/L$ in 10 days. Thereafter, cultivation of Scenedesmus sp. was performed in 1000 mL Duran bottle with air bubbling. The highest Scenedesmus sp. specific growth rate of $0.321{\pm}0.01/d$ was obtained in treatment using liquid fraction after aerobic digestion as the whole culture medium for Scenedesmus sp. cultivation. With this study, digestion of $8,800{\pm}128.12mg\;dry\;weight/L$ of settleable solids from fish pond finally produced $1,235{\pm}21mg\;dry\;weight/L$ of Scenedesmus sp. biomass.

• Journal of Microbiology and Biotechnology
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• 제14권1호
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• pp.158-161
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• 2004

Scenedesmus spp. were cultured for 51 days in newly developed medium, KEP I (Kim and Ecopeace: initials of corresponding author and environmental company) made with Bacterio-Mineral-Water (3%, v/v) that had been bio-reacted with swine urine medium to 10% (v/v) Bold's Basal medium, and investigated for cancer chemopreventive potential by measuring the induction of quinone reductase (QR), glutathione S-transferase (GST), and reduced glutathione (GSH), and inhibition of cytochrome P450 (CYP) 1A1 activity. The activitives of QR and GST of Scenedesmus spp. cultured in KEP I medium were increased by 3.0-fold and 1.5-fold, respectively. However, Scenedesmus spp. cultured in control medium (CT) increased the activitives of QR and GST by 1.8-fold and 1.3-fold, respectively. Scenedesmus spp. in KEP I medium strongly inhibited CYP 1Al activity. These results show that Scenedesmus spp. in KEP I medium has cancer chemopreventive potential and may be a candidate for further development as a chemopreventive agent.

• 생태와환경
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• 제44권2호
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• pp.129-135
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• 2011

팔당호, 경안천과 하수처리수에서 Scenedesmus sp.가 성장이 가능하고 영양 염류를 제거할 수 있는지를 확인하였다. TN과 TP 농도가 각각 1.9과 0.02 mg $L^{-1}$인 팔당호 광동교에서 채취한 시료에 Scenedesmus sp.를 접종한 다음, 교반한 경우에 미세조류가 증식하고 영양 염류 농도가 50% 감소하였다. 또 TN과 TP 농도가 3.0과 0.09 mg $L^{-1}$인 경안천 시료에 Scenedesmus Sp.를 접종한 결과, 규조류 등과 경쟁에 의하여 미세조류 현존량은 239~259 chl. ${\alpha}\;m^{-3}$로 낮았으나, 역시 영양 염류는 접종율과 관계없이 약 50% 감소하였다. 하수처리수에는 이미 Scenedesmus sp.가 존재하고 있었고 대조구와 접종한 실험구 사이에는 미세조류의 현존량의 작은 차이가 있었으나 처리효율은 큰 차이가 없었다. 팔당호와 같은 상태의 영양 염류를 가지고 있는 자연수에서는 Scenedesmus sp.를 접종하고 교반을 가하면, 미세 조류의 생체량이 증가하고 영양염류를 제거할 수 있음이 확인되었고 하수처리수에서는 따로 Scenedesmus sp.를 접종하지 않아도 영양 염류를 제거할 수 있음을 확인하였다.

• Journal of Plant Biology
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• 제28권4호
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• pp.305-315
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• 1985

Morphological variations within the species of Scenedesmus in Korea, S. armatus and 2 strains of S. quadricauda were investigated. Taxonomic characters such as length of long spine, ridge, unicell-colony transformation, and colony types were compared. The length of long spine was constant, whereas the distribution of the spine varied with the age of culture. Ridge and short spine in S. armatus occurred constantly, whereas those in S. quadricauda varied with the composition of the media and age of culture. Strains CY-1 and CY-2 showed 6 different colony types in the stationary culture, whereas S. armatus formed only two types, armatus and armatus-longus types. All strains showed unicell-colony transformation. The cell became minimum when the daughter cell was released, and reached maximum at division.

• Journal of Microbiology and Biotechnology
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• 제10권3호
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• pp.300-306
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• 2000

The rate of apparent nitric oxide (NO) release, as measured in the exhaust gas of green alga, Scenedesmus obliquus, depended on the light intensity and pH. It doubled after lowering the temperature from $25^{\circ}C{\;}to{\;}15^{\circ}C$ and strongly decreased from $35^{\circ}C{\;}to{\;}42^{\circ}C$. The Scenedesmus cells, deficient in nitrogen or phosphorus, demonstrated a significant increase in NO production following their transfer to nitrate- and phosphate-rich media. The addition of herbicides (DCMU and glyphosate) or toxic concentrations of $Cu^{2+}{\;}or{\;}Fe^{3+}$ produced strong NO peaks, resembling those that occurred after sudden darkening. An increase in the $Ni^{2+}$ concentration to 20 ppm resulted in a gradual increase of NO release from the initial ~1.5 ppbv to>20 ppbv, whereas $Cd^{2+}$ instantaneously suppressed the NO by the cultures of Scenedesmus was not altered by L-NNA, an inhibitor of nitric oxide synthase (NOS), or by its substrate, L-arginine. This seems to exclude the role of NOS in the NO formation under study. Accordingly, it can be assumed that the rate of NO formation is mainly a function of dynamic nitrite pool sizes and environmental factors significantly affect the NO production in algae.

• KSBB Journal
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• 제25권4호
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• pp.371-378
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• 2010

For the biodiesel fuel production from microalgae, the lipid from wet and dry samples of green algae Scenedesmus sp. was extracted by using various solvents and pre-treatment methods. Extraction yield of the lyophilized sample was better than that of dry sample. Chloroform/methanol (2:1, v/v) and ultrasonication or homogenization method were also selected as the most effective solvent and pre-treatment methods for lipid extraction, respectively. Under these constraint conditions, optimization experiment of lipid extraction was investigated by Taguchi approach using orthogonal matrix $L_9$ ($3^4$) method. The optimum extraction conditions of lipid extraction was obtained at pre-treatment of homogenization, extraction time of 5 hour, temperature of $35^{\circ}C$, and solvent ratio of 1:20 (w/v). Yield of extraction at optimized condition was 20.55% and it was 96% of total lipid content (21.38%) of Scenedesmus sp.

• 한국환경보건학회지
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• 제5권1호
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• pp.61-65
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• 1978

To investigate the phytoplankton distribution effected by polluted water, this research was carried out at eight sampling places in Tae-jun and one sampling place in Kang-kyong during the period from May 10 to July 25, 1977. The results are as follows. 1) The range of water temperature was 21.0~36.0$\circ$C (May 10~July 25), and pH value was in the range of 3.5~11.0. 2) BOD was generally high (140~432mg/l) 3) At the places where BOD was high, dominant species were Aphanocapsa rivularis, Microcystis aeruginosa and Oscillatoria sp. belonging to Cyanophyta, Chlorella sp. belonging to Chlorophyta, Euglena sp. belonging to Euglenophyta, and Navicula exqua and Navicula sp. belonging to Chrysophyta. 4) At the places where the range of pH value was 3.5~3.8 and the range of BOD value was 134~148mg/l, observable species were Scenedesmus ellipsoideus and Pandorina morurn belonging to Chlorophyta, Navicula exqua belonging to Chrysophyta and Euglena sp. belonging to Euglenophyta. 5) At the places where the range of pH value was 9.0~11.0 and the range of BOD value was 214~220mg/l, a few observable species were Scenedesmus carinatus, Scenedesmus ellipsoideus, Scenedesmus bijuga and Scenedesmus obundance belonging to Chlorophyta.

• 상하수도학회지
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• 제27권3호
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• pp.325-329
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• 2013

A result of estimating the effects of initial phosphorus concentration and nitrogen sources on removal of nitrogen and phosphorus in wastewater treatment using Scenedesmus dimorphus shows that there was no difference in microalgae growth amount and nitrogen removal amount by phosphorus concentration(5 ~ 60 mg/L). On the other hand, as initial phosphorus concentration increased, phosphorus removal amount was increased by luxury uptake of microalgae. Scenedesmus dimorphus preferred to ammonia when ammonia(40 mg/L) and nitrate(40 mg/L) are simultaneously presented and nitrogen removal rate of ammonia was high at approximately 20 mg/L/day.

• 미생물학회지
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• 제27권4호
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• pp.373-377
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• 1989

The effects of environmental factors on the extracellular release of organic carbon by Scenedesmus qudricauda were studied. The PER (percentage extracellular release) was greater at high temperature and at high concentration of nitrogen and phosphate. The PER variation according to the change of M/P ratio showed high values at each extreme N/P ratio. This result suggested that the limitation of nitrogen or phosphorous resulted in the accumulation of carbohydrates as photosynthetic products, and the products in high concentration were excreted through algal cell membrane.

• International journal of advanced smart convergence
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• 제7권1호
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• pp.48-63
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• 2018

The combination of Simian Virus40 (SV40)'s large T antigen with its replication origin is commonly used in molecular studies to enhance the expression of heterogeneous genes through multiplying the plasmid copy number. There are no reports related to the impact of the SV40 T antigen on plant, multiple fissional, cell-type. This study explores the response of two multiple-fission microalgal cells, Scenedesmus quadricauda and Chlorella vulgaris, to the expression of the T-antigen, with aim of applying SV40 T-antigen to increase the expression efficiency of foreign genes in the two species. Different levels of low-expression have been constructed to control the expression of SV40 T antigen using three heterogenous promoters (NOS, CaMV35S, and CMV). Chlorella cultures showed slowdown in the growth rate for samples harboring the T antigen under the control of CaMV35S and CMV promoters, unlike Scenedesmus cultures which showed no significant difference between samples and could have silenced the expression.