• Journal of Aquaculture
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• v.17 no.1
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• pp.58-61
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• 2004

Larvae of Pandalus gracilis were reared in the laboratory under controlled conditions (salinity, 32.5∼34.5; photo-periods, 12L: 12D). The experiments were designed to examine effects of temperature (10 and 2$0^{\circ}C$) on larval development, survival, intermolt period and larval growth. The higher survival rate was obtained at 2$0^{\circ}C$ than at 1$0^{\circ}C$ and larvae reached later stages at 2$0^{\circ}C$. Intermolt period increased significantly with increasing of instar number and was longer at 1$0^{\circ}C$ than at 2$0^{\circ}C$.

• Proceedings of the Korean Society for Applied Microbiology Conference
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• 1979.10a
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• pp.244.1-244
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• 1979

An attempt was made to produce by using Rh. gracilis (NRRL Y-1091) in the same wav as currently considered siglecell protein production. The lipid content of Rh. gracilis were 56.9％ of dry weight. Economic coefficient (E. C.) and fat coefficient (F. C.) were 31.3 and 17.8, respectivelv. The lipid and fats extracted from Rh. gracilis were characterized as following: Specific gravity 0.875, A.V. 42.5, S.V. 220, I.V. 57.7, Phospholipid 1.58, Unsaponifiables 25.5, Volatile matter 18.7. Fatty acid composition of the lipids were analvzed by HPLC. In addition to the lipid analvsis, proteins were extracted from defatted Rh. gracilis and their amino acid compositions were examined by amino acid analyzer.

• Korean Journal of Ichthyology
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• v.4 no.2
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• pp.63-71
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• 1992

The Ichthyofauna was investigated at the seven sites in Paikchon streams from August 1990 to March 1991. The collected fishes were classified to 22 species belong to 19 genera and 11 families, of which 5 species were tentatively identified as endemic species in Korea. Three species, Odontobutis obscurus interrupta, Luciogobius guttatus and Mactopodus chinensis, are collected for the first time in this area. Dominant species were Squalidus gracilis majimae(40.8%), Zacco temmincki(24.2%), Z. platypus(13.3%) and Cobitis koreensis pumilus(7.7%). Stomach contents of S. gracilis majimae were mainly taxa belong to Bacillariophyceae of micro-algee attached to sand or gravel.

• KSBB Journal
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• v.15 no.6
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• pp.644-648
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• 2000

Biological fixation of carbon dioxide using microalgae is known as an effective CO$_2$reduction technology. However, many environmental factors influence microalgal productivity. Optimal cultivation factors were determined for the green alga, Euglena gracilis Z, which offers high protein and vitamin E content for animal fodder. In batch culture in a photovioreactor, it was found that theinitial pH, temperature, CO$_2$concentration in air, and light intensity during the optimal cultivating conditions were 3.5, 27$^{\circ}C$, 5-10% and 520 ${\mu}$mol/㎡/s, respectively. When tap water and freshwater were used as cultivating media unsterilized tap water was found to be effective. A kinetic model was considered to determine the relationship between the specific growth rate and the light intensity. The half-velocity coefficient (K(sub)I) in the Monod model under photoautotrophic conditions was 978.9 ${\mu}$mol/㎡/s.

• Korean Journal of Ecology and Environment
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• v.38 no.1 s.110
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• pp.63-72
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• 2005

The fish fauna and community structure were investigated in the Lake Cheongpyeong, Korea, from August 2003 to April 2004. During the period, 43 species belonging 10 families were collected. There were 18 Korean endemic species 41.9%. The five dominant species numerically were A. gracilis (17.4%), Zacco platypus (14.6%), A. yamatsutae (13.2%), Hemibarbus labeo (11.9%), Rhinogobius brunneus (11.7%), and Zacco temmicki (3.0%). The five dominant species in biomass were Erythroculter erythropterus (15.07 kg), H. labeo (13.21 kg), Carassius cuvieri (6.47 kg), A. gracilis (6.05 kg), and Z. platypus (4.71 kg). Of 6 exotic fishes in the lake C. cuvieri, Lepomis macrochirus and Micropterus salmoides were originated from foreign countries but Anguilla japonica, Tridentiger brevispinis, and Chaenogobius urotaenius were introduced from other watershed in Korea.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.44 no.4
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• pp.378-382
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• 2011

The feeding ecology of bluefin searobin Chelidonichthys spinosus around Jeju Island was examined. Specimens were caught every autumn from 2004 to 2007. The primary prey items of C. spinosus included fish, shrimp, and crabs. Chelidonichthys spinosus preyed upon a wide range of sub-pelagic crustacean groups(e.g., Leptochela gracilis, Leptochela sydniensis). This species was also an opportunistic feeder, exploiting the available prey groups in each area(i.e., L. gracilis in the South Sea and East China Sea groups and L. gracilis and L. sydniensis in the Yellow Sea group). The main prey group of this species changed from demersal shrimp to pelagic shrimp with prey environmental changes. Observed ontogenetic shifts in diet were relatively clear despite substantial overlap between the 10 cm and 20 cm C. spinosus groups.

• Korean Journal of Ecology and Environment
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• v.38 no.2 s.112
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• pp.207-216
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• 2005

Spawning behaviors of Squalidus gracilis majimae (Cyprinidae) were observed in the laboratory whose environmental factors such as light (D/L = 16 : 8), temperature ($20\;{\sim}\;24\;＾{\circ}C$), and dissolved oxygen (>8 mg $L^{-1}$) were quite regularly controlled. The behavioral patterns were categorized into three stages ofpre-spawning, spawning, and Post-spawning behaviors. In Particular, the pre-spawning stage was specified by 11 specific behavioral patterns of aggressive mating behaviors. During the spawning stage, the male and female performed four distinct spawning behaviors including sexual temptation, stimulation, egg spawning, and the separation, and randomly laid about 200 ${\sim}$ 300 eggs on the bottom substrates through the night. After finishing spawning, two adults separated toward their refuges and showed 3 types of post-spawning behaviors such as the resting, occasional eggs protecting, and the egg eating. The fish was identified as a partial-parental care species after the spawning.

• YAKHAK HOEJI
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• v.32 no.6
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• pp.420-427
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• 1988

Post-translational modification of protein amino acid residues is a well known metabolic phenomenon. One such side chain modification, protein methylation, occur ubiquitously in nature, in organism ranging from prokaryotic to eukaryotic and the biological significance of protein methylation has begun to emerge. The observation that cytochrome C methylation facilitates the binding of this hemoprotein to mitochondria could be placed as the one of the examples along this line. However, the detail biological meaning of cytochrome C methylation is remained to be clarified. In the aspect of such reason this research was done. The results of this experiment were; 1) pure Euglena gracilis cytochrome C552 was isolated, 2) methylarginine and methylmethionine were not found in cytochrome C552 sequence, 3) however, Unknown Peak at 20.78min of retention time was found, and 4) this Unknown Peak was found only from Euglena cytochrome C552, so far.

• Journal of Plant Biology
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• v.33 no.2
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• pp.127-134
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• 1990

Three marine species of Cladophora (Cladophoraceae, Chlorophyta) commonly occurred on the coast of Cheju Island, Cladophora conchopheria Sakai, C. gracilis (Griff.) Kutzing and C. wrightiana Harvey were described morphologically, considering their taxonomic characters. C. conchopheria Sakai, specifically growing on the surface of Lunella coronata, is a very minute plant of 550-990 ${\mu}{\textrm}{m}$ in height and has intracuticular adventitious rhizoids borne from the lower portion of the first to fourth segments. C. gracilis occurs on calm habitat and shows a pseudosympodial growth with pectinate branchlets. c. wrightiana always produces protoplasmic protuberances at the node of middle portion of thallus. It grows to 30 cm or more in height and is dark green in subtidal bottom.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.17 no.2
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• pp.132-138
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• 1984

The genus Squalidus of Korea, formerly regarded as genus Gnathopogon is reviewed and keys to following 4 species and subspecies: S. gracilis majimae, S. chankaensis tsuchigae, S. chankaensis ssp., and S. japonicus coreanus. The genus spualidus is distinguished from genus Gnathopogon by the position of snout, color pattern on the body sides, number of scales above lateral line, and distance from anus to anal finorgin. G. majimae Jordan et Hubbs is junior synonym of S. gracilis majimae, and G. coreanus (not Berg) is splitted and identified as S. chankaensis tsuchigae, S. c. ssp., and S. japonicus coreanus. S. c. tsuchigae is very similar to S. j. coreanus, but the eye diameter, barbel length, and the number of lateral line scales are useful characters in separating these species. S. thankaensis ssp. occurring only in the Yongdok-Oship River differs from S. chankaensis tsuchigae in the number of lateral line scales, eye diameter and their body size.