• 대한환경공학회지
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• 제34권9호
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• pp.630-636
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• 2012

본 연구는 해양미세조류 Dunaliella salina을 LED 광원을 이용하여 배양한 연구로 배양에 필요한 최적의 파장, 광도, 공기공급속도 및 배양온도를 찾기 위하여 수행되었다. 낮은 배양온도에서보다는 높은 온도에서 성장이 빨랐으나, 본 실험에서는 $22^{\circ}C$에서 가장 잘 성장하는 것으로 확인되었다. LED 파장에 따른 성장실험에서는 백색 LED가 배양에 가장 효과적이었으며, 광도에 따른 실험에서는 실험 시 고려한 3가지 광도 중(3,000, 6,300, 8,000 Lux) 3,000 Lux에서 최대 세포농도인 1.30 g/L를 나타내었다. 공기공급속도의 증가는 Dunaliella salina의 성장속도와 반비례의 관계를 나타내었는데, 공기를 공급하지 않은 경우의 비증식속도 $1.12day^{-1}$와 비교하면 공기공급은 본 미세조류의 성장에 저해요인으로 작용함을 알 수 있었다.

• ALGAE
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• 제28권2호
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• pp.203-211
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• 2013

Dunaliella salina and Dunaliella bardawil are well known for carotenogenesis, the overproduction of carotenoids, under stress conditions. The effect of high light (HL) and low light (LL) on the growth, morphology, photosynthetic efficiency, and the ${\beta}$-carotene and zeaxanthin production of D. salina CCAP 19/18 and D. bardawil was investigated and compared. Both strains showed similar growth kinetics under LL growth condition, but D. salina CCAP 19/18 was faster. As the light intensity increased, D. salina CCAP 19/18 cells were elongated and D. bardawil cells became larger. Both strains showed decrease of the maximum quantum yield of PSII ($F_v/F_m$) and election transport rate (ETR) under HL growth condition and D. salina CCAP 19/18 was less liable to the light stress. Both strains had about 1.8 and 5 times difference in the $O_2$ evolution rate at LL and HL conditions, respectively. The ${\beta}$-carotene and zeaxanthin production were increased as the light intensity increased in both strains. D. bardawil was more sensitive to light intensity than D. salina CCAP 19/18. The possible application of D. salina CCAP 19/18 as a carotenogenic strain will be discussed.

• 한국미생물·생명공학회지
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• 제40권3호
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• pp.282-285
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• 2012

본 연구는 혐기성 소화조에서 바이오 가스 생산을 위한 바이오매스 자원으로서 Chlorella vulagaris와 Dunaliella salina의 이용능력을 확인하였다. 세포벽의 구조에 따라 전처리 후 용해성 물질의 수율이 영향을 받았는데, 이는 D. salina가 바이오 가스 생산 측면에서 C. vulgaris보다 좋은 후보라는 것을 보여준다. 혐기성 소화조에서 얻은 접종원으로부터 전처리하거나 전처리하지 않은 D. salina를 기질로서 메탄가스를 생산하는데 이용하였을 때 메탄 수율 측면에서 큰 차이가 없었다. 그러므로 D. salina는 높은 바이오매스 생산성, 단순한 전처리 필요성, 쉬운 바이오 가스전환 때문에 바이오 가스 생산을 위한 적합한 해조류 바이오매스이다.

• 한국수산과학회지
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• 제45권1호
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• pp.25-29
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• 2012

Marine actinomycetes isolated from seaweed were screened for growth activation effects on the biodiesel-producing microalgae Dunaliella salina. Of the 98 actinomycetes studied, strain 288-11 isolated from the rhizosphere of Undaria pinnatifida showed potent growth activation. The strain was identified as Streptomyces anulatus based on 16S rDNA sequence analysis. The cell density increased up to 2.1-fold with the addition of 1 mg/mL of extract to the medium. To understand the effect of adding S. anulatus extract, the gross biochemical composition and fatty acids of D. salina were determined.

• Journal of Microbiology and Biotechnology
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• 제18권5호
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• pp.821-827
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• 2008

The unicellular green alga Dunaliella salina is a halotolerant eukaryotic organism. Its halophytic properties provide an important advantage for open pond mass cultivation, since D. salina can be grown selectively. D. salina was originally described by E. C. Teodoresco in 1905. Since that time, numerous isolates of D. salina have been identified from hypersaline environments on different continents. The new Dunaliella strain used for this study was isolated from the salt farm area of the west coastal side of South Korea. Cells of the new strain were approximately oval- or pear-shaped (approximately $16-24\;{\mu}m$ long and $10-15\;{\mu}m$ wide), and contained one pyrenoid, cytoplasmatic granules, and no visible eyespot. Although levels of $\beta$-carotene per cell were relatively low in cells grown at salinities between 0.5 to 2.5 M NaCl, cells grown at 4.5 M NaCl contained about a ten-fold increase in cellular levels of $\beta$-carotene, which demonstrated that cells of the new Korean strain of Dunaliella can overaccumulate $\beta$-carotene in response to salt stress. Analysis of the ITS1 and ITS2 regions of the new Korean isolate showed that it is in the same clade as D. salina. Consequently, based on comparative cell morphology, biochemistry, and molecular phylogeny, the new Dunaliella isolate from South Korea was classified as D. salina KCTC10654BP.

• Journal of Plant Biology
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• 제36권3호
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• pp.293-296
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• 1993

Effects of dark treatment and N1-dichlorophenyl-N3-dimethylurea (DCMU) on the desaturation of galactolipids of Dunaliella salina were investigated to see whether light-driven photosynthetic electron transport is involved in in vivo desaturation of galactolipids. The incorporation of radioactive fatty acid precursors ([14C]lauric acid) into galactolipids, mainly composed of prokaryotic molecular species, was most affected among different polar lipid classes by both treatments. The analysis of specific radioactivities of individual galactolipid molecular species revealed that their synthesis was greatly inhibited by the treatments except for eukaryotic molecular species, 18 : 3/ 18 : 3 digalactosyldiacylglycerol, whose desaturation occurs in endoplasmic reticulum.

• Fisheries and Aquatic Sciences
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• 제19권7호
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• pp.31.1-31.6
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• 2016

Background: The objective of this study was to develop an efficient selectable marker for transgenic Dunaliella salina. Results: Tests of the sensitivity of D. salina to the antibiotic chloramphenicol and the herbicide Basta$^{(R)}$ showed that cells ($1.0{\times}10^6cells/ml$) treated with 1000 or $1500{\mu}g/ml$ chloramphenicol died in 8 or 6 days, respectively, whereas D. salina cells ($1.0{\times}10^6cells/ml$) treated with 5, 10, 20, or $40{\mu}g/ml$ Basta$^{(R)}$ died in 2 days. Therefore, D. salina is more sensitive to Basta$^{(R)}$ than to chloramphenicol. To examine the possibility of using the phosphinothricin N-acetyltransferase (pat) gene as a selectable marker gene, we introduced the pat genes into D. salina with particle bombardment system under the condition of helium pressure of 900 psi from a distance of 3 cm. PCR analysis confirmed that the gene was stably inserted into the cells and that the cells survived in $5{\mu}g/ml$ Basta$^{(R)}$, the medium used to select the transformed cells. Conclusions: The findings of this study suggest that the pat gene can be used as an efficient selectable marker when producing transgenic D. salina.

• ALGAE
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• 제26권1호
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• pp.3-20
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• 2011

The physiology of the unicellular green alga Dunaliella salina in response to abiotic stress has been studied for several decades. Early D. salina research focused on its remarkable salinity tolerance and ability, upon exposure to various abiotic stresses, to accumulate high concentrations of $\beta$-carotene and other carotenoid pigments valued highly as nutraceuticals. The simple life cycle and growth requirements of D. salina make this organism one of the large-scale commercially exploited microalgae for natural carotenoids. Recent advances in genomics and proteomics now allow investigation of abiotic stress responses at the molecular level. Detailed knowledge of isoprenoid biosynthesis mechanisms and the development of molecular tools and techniques for D. salina will allow the improvement of physiological characteristics of algal strains and the use of transgenic algae in bioreactors. Here we review D. salina isoprenoid and carotenoid biosynthesis regulation, and also the biotechnological and genetic transformation procedures developed for this alga that set the stage for its future use as a production system.

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

• Journal of Microbiology
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• 제43권4호
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• pp.361-365
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• 2005

In this study, we chronicle the establishment of a novel transformation system for the unicellular marine green alga, Dunaliella salina. We introduced the CaMV35S promoter-GUS construct into D. salina with a PDS1000/He micro-particle bombardment system. Forty eight h after transformation, via histochemical staining, we observed the transient expression of GUS in D. salina cells which had been bombarded under rupture-disc pressures of 450 psi and 900 psi. We observed no GUS activity in either the negative or the blank controls. Our findings indicated that the micro-particle bombardment method constituted a feasible approach to the genetic transformation of D. salina. We also conducted tests of the cells' sensitivity to seven antibiotics and one herbicide, and our results suggested that 20 ${\mu}g$/ ml of Basta could inhibit cell growth completely. The bar gene, which encodes for phosphinothricin acetyltransferase and confers herbicide tolerance, was introduced into the cells via the above established method. The results of PCR and PCR-Southern blot analyses indicated that the gene was successfully integrated into the genome of the transformants.