• Journal of the Korean Society of Tobacco Science
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• v.18 no.1
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• pp.39-48
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• 1996

A storage protein(SP-2) was confirmed in haemolymph during larval-pupal-adult development of tobacco burdworm(Helicoverpa assulta Guenee), and its biochemical characteristics were investigated. The titer of SP-2 showed a peak at mature larva, decreased gradually through the late pupal stage, and became undetectable at adult period. As the results from electrophoretic mnysis, SP-2 was confirmed to be glycolipoprotein(M.W. 332kDa) relatively stable to heat( $\leq$ 68$^{\circ}C$ ). This storage protein was determined to be a tetramer composed of a single subunit with MW of 83kDa, and the isoelectric point was 5.7. The amino acid composition of the SP-2 was characterized. It has relatively high content of methionine and histidine, whereas the contents of tyrosine and phenylalanine were relatively low.

• Journal of Sericultural and Entomological Science
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• v.43 no.2
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• pp.67-76
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• 2001

The "crescent-egg" a new spontaneous mutant was detected in a white egg strain k37. Studies were carried out the linkage analysis, to investigate phenotypic characteristics and biochemical analysis of haemolymph and ovarian protein. The mutant, ore was independent from 20 linkage groups P(2), Ze(3),L(4), oc(5), sn8), Ia(9), w-1(10), K(11), ch(13), U(14), bl(15), cts(16), bts(17), mln(18), nb(19), oh(20),Lan(21), or(22), tub(23) and Xan(27). The fertilization, hatchability and larval growth were not different from the those of normal eggs. The content and composition of yolk protein were similared to normal eggs. Scanning electron microscopy revealed the areal specific structure in dorsal region of egg-shell of cre mutant. Analysis of chorion protein by isoelectrofocusing(IEF), was resolved no difference in the composite of the chorion protein. We conclude that the egg mutant ere is expressed only in the egg-shape formation and region specific determination.

• Korean Journal of Ichthyology
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• v.11 no.1
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• pp.72-85
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• 1999

A study on the larval fish assemblage around the front area was conducted in the Korea Strait in August, 1993. The front was found in the shelf break located in $35{\sim}36^{\circ}N$. A total of 125 species were found in the study area. Of these Engraulis japonicus was the most dominant species comprising 84.3% of the total fish larvae collected and followed by Maurolicus muelleri accounting for 7.7%. Gobiidae, Callionymidae and Pomacentridae showed higher frequency of occurrence. These five species can be divided into three groups. First group was comprised in the larval fish species such as E. japonicus and Callionymidae which were found in the whole study area. The second group was comprised of Gobiidae and Pomacentridae which were found in the warm area located in the southern part of the front area. The other species was M. muelleri found in the cold area located in the northern part of the front area including the front area. The assemblage, geological distribution and body length composition of the fish larvae in the Korea Strait would be mainly determined by the spawning ecology of the fishes, and the geological distribution and structure of the front which is formed in the ocean boundary between the Tsushima Current and the East Sea Cold Water.

• Journal of Aquaculture
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• v.19 no.1
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• pp.52-56
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• 2006

This study was conducted to investigate the effects of three different concentrations (6%, 8% and 10% final volume) of dimethyl sulfoxide (DMSO) on cryopreserved sperm of grass carp (Ctenopharyngodon idellus). Grass carp sperm was suspended in Kurokura extender #2 and equilibrated at $4^{\circ}C$ for 10 min. French straws (0.25 ml) of sperm were frozen from $4^{\circ}C\;to\;-4^{\circ}C$ at a rate of $4^{\circ}C\;min^{-1}$ and then ken $-4^{\circ}C\;to\;-80^{\circ}C$ at a rate of $11^{\circ}C\;min^{-1}$. The straws were kept at $-80^{\circ}C$ for 10 min and finally stored in liquid nitrogen $(-196^{\circ}C)$. The cryopreserved sperm was thawed in a water bath at $40^{\circ}C$ for 30 sec and fertilization, hatching rate and larval malformation were compared with fresh sperm (control). The fertilization rate of post-thawed sperm was comparable (from 88.21% to 94.30%) to that of fresh sperm. However, hatching rate of all frozen sperm were significantly lower (P<0.05) than that of control. Additionally, the larval abnormality rate of frozen sperm was significantly higher than that of fresh sperm. The results indicate that DMSO could affect the quality of cryopreserved sperm of grass carp, and a freezing program and a proper extender composition should be further studied.

• Journal of Life Science
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• v.17 no.8 s.88
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• pp.1046-1052
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• 2007

Transferrin is a molecule carrying iron to store and maintain for iron homeostasis of living organisms. In this study, we have purified transferrin, as an iron-binding protein, from the last larval haemolymph of Papilio xuthus by KBr density gradient ultracentrifugation and gel filtration (superose 6 HR) using fast protein liquid chromatography (FPLC) and transferrin containing iron was identified by Ferene S staining. The purified haemolymph transferrin was shown to have molecular mass of 78 and 80 kDa and amino acid composition of transferrin was rich in aspartic acid, valine, leucine and glutamic acid. With immuno-diffusion assay, we confirmed the existence of the transferrin in the haemo-lymph and fat body by detection of visible and clear positive reaction. From the quantitative comparison by rocket immuno-electrophoresis process, the amount of transferrin were increased in the haemolymph of 3 days after pupation and the whole 5 days after pupation. Here, with biochemical and immunohistochemical analysis, we speculate the relationship of transferrin between the physical characteristics and distribution during metamorphosis of P. xuthus.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.51 no.5
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• pp.549-555
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• 2018

The objectives of this study were to confirm the nutritional requirements and improve the survival of the walleye pollock Theragra chalcogramma, a cold seawater fish, by enrichment. We analyzed the fatty acids and amino acids of fertilized pollock eggs before hatching, just-hatched larvae, larvae that had absorbed only the yolk sac, and larvae starved for 2 days after yolk absorption. For the survival improvement experiment, we administered docosahexaenoic acid (DHA), eicosapentaenoic acid (EPA), and DHA-EPA enrichment. Fatty acid decreased DHA and EPA content. On the $30^{th}$ day, body growth was significantly greater in pollock given the EPA and DHA-EPA treatments (P<0.05). Larval survival at 20 and 30 days after hatching (DAH) was greatest under the DHA-EPA treatment (P<0.05). Survival was significantly lower under the EPA treatment at 10 DAH, but then increased to approach that seen under the EPA-DHA treatment (P<0.05). Therefore, we determined that reduced survival in hatchlings of high-mortality pollack could be improved by controlling EPA and DHA content during enrichment. We conclude that cold seawater fish must be given feed that meets their nutritional needs, which can be accomplished using newly manufactured enrichment products for the larvae of cold seawater fish, such as pollock.

• Korean Journal of Environmental Biology
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• v.39 no.4
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• pp.471-478
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• 2021

Effective microorganisms (EM), which are sources of fermentation byproducts in herbal medicine, were compared with oyster mushrooms(OM) to identify alternative larval feeds for white-spotted flower chafer (Protaetia brevitarsis seulensis). The nutritional composition of each fermented feed was analyzed. The content of crude protein, crude fat, and fiber was higher in the OM fermented feed, except for crude ash. No difference in nutritional content of larvae based on fermented feed was observed. A comparative weekly analysis of the live weights of larvae was based on the fermented feed used. The average weight was significantly higher in the feeds using EM and OM from third week of observation. The larval survival rate in the presence of fermented feed was 96.7% compared with 9.8% with non-fermented feed. The results suggest that fermented food source is essential for the growth of white-spotted flower chafer, and OM was a stable alternative to EM as a fermentation source for the survival of white-spotted flower chafer.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.19 no.5
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• pp.509-517
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• 1986

Abundances of small fishes that utilized eelgrass meadows of Hansilpo, Chungmu, were analyzed to determine fish species composition and monthly changes of this temperate seagrass fish community during 1983-1986. A total of 4,646 fishes that comprised 35 species in 19 families was collected during the period of investigation. Pholis taczanowskii, Pseudoblennius cottoides, Tridentiger trigonocephalus, and Sryngnathus schlegeli predominated in ichthyofauna that occupied the eelgrass meadows most of the year. These four most abundant fish species accounted for approximately $64\%$ of the number of fish collected. Juveniles of economically valuable fish species such as Sebastes inermis, Platycephalus indicus and Limanda yokohamae were also collected in the study area. Seasonal changes in both species composition and abundances of fish populations were major characteristics in these eelgrass meadows. A peak abundance of total fishes occurred during spring, with a secondary peak during fall. The lowest abundance of total fishes occurred in winter. Each abundant fish species showed its own seasonal abundance pattern, and a peak abundance 1-3 months separated from other species with some overlap of the increased larval recruitment.

• Korean journal of applied entomology
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• v.50 no.1
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• pp.55-63
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• 2011

This study was conducted to develop an artificial diet for the mugwort looper, Ascotis selenaria (Lepidoptera: Geometridae), which is an insect pest to leaves of citrus (Citrus unshiu). Corn and soybean powder were selected as main nutrient sources for larvae of A. selenaria after several diets consisted of wheat germ, corn, kidney bean and/or soybean were tested for larval development and survival. A higher amount of the main nutrients in the diet increased the larval survivorship. Addition of yeast and cholesterol in diet increased the larval survivorship. Finally the composition of diet was decided as followings; corn 100 g, soybean 100 g agar 25 g, Brewers' yeast 30 g, cholesterol 0.5 g, Vanderzant vitamin mixture 2 g, Wesson's salt mixture 2 g, sorbic acid 2 g, ascorbic acid 2 g, and methyl-4-hydroxybenzoate 2.5 g, and distilled water 1 liter. Development periods of larvae and pupae, survival rate and fecundity of A. selenaria reared on the diet were not significantly different with those on the host plant, citrus leaves. Larvae of early instars were reared in a group, while larvae of later instars (5-6th) were reared individually. Adult mating was conducted in a plastic cage and an oilpaper covered with a gauze was provided as an oviposition site.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.32 no.5
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• pp.654-658
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• 1999

To investigate an efficient microalgal feed for lariat culture of the Pacific oyster Crassostrea gigas, we prepared three types of Isochrysis aff, galbana (T-iso) : 1) freshly Harvested feed, 2) concentrated feed and 3) freeze-dried feed. The chemical compositions and fatty acid content of these feeds were evaluated and survival rate and lipid content of oyster larvae fed by these feeds were also determined. There was no significant difference in all types of feed in the gross biochemical compositions, In the fatty acid composition, the freeze-dried feed showed a significant increase in the level of polyunsaturated fatty acid (PUFA), eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) than freshly Harvested feed, especially EPA was 7.35-fold higher than freshly Harvested feed. The survival rate of the oyster larvae was the highest when the larvae were fed with a diet of $10\%$ freeze-dried and $90\%$ concentrated feed; it was 2.1-fold higher than that fed with freshly Harvested food alone. Thereafter, the survival rate decreased with the increased substitutions of freeze-dried food, finally equalling that fed $100\%$ freshly harvested feed at the $30\%$ substitution. Larval lipid content of the oyster was also the highest when the larvae were fed with a diet of $10\%$ freeze-dried and $90\%$ concentrated feed. This increase was by 1.6-fold ver that fed $100\%$ freshly Harvested cells. Thus feed produced during slack times, on a seedling aquaculture farm, and preparedas a freeze-dried diet can be used, mixed with concentrated feed, to supply diets more efficiently and to improve the larvae survival rate of Pacific oyster.