• Journal of fish pathology
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• v.15 no.2
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• pp.77-82
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• 2002

Effects of stress-induced suppression of humoral immunity on scuticociliate killing activity of olive flounder plasma were investigated. Changes in glucose level. alternative complement activity and Iysozyme activity of plasma by handling stress were analysed in relation to in vitri parasiticidal activity of plasma. The plasma glucose level was about two times higher in fish after a handling stress than in control fish. Plasma lysozyme activity and natural haemolytic activity were decreased in suessed fish.The scuticociliate killing activity of plasma was significantly lower in stressed fish than in non-stressed control fish. The present results indicated that stress-induced immunodepression could be a cause of scuticociliatosis occurrence in olive flounder.

• Journal of fish pathology
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• v.15 no.2
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• pp.93-97
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• 2002

The scuticociliate, a histophagous ciliate, is known to cause high cumulative mortalities in juvenile olive flounder Paralichthys olivaceus rearing in land-based tank facilities. This study examined effects of bath treatment of 3 chemical agents including formalin, hydrogen peroxide and sodium chloride. and freshwater against scnricociliates infected olive flounder. Although 100 ppm formalin and freshwater did not completeIy eliminale ue scuticociliates within the internal organ of fish, chemicals were effective to prevent scuticociliatosis from spreading. It confirms the efficacy of the chemical with treating the diseased fish for at least 4 consecutive days.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2016.10a
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• pp.113-114
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• 2016

In this study, various fats and oils were soaked in low-strength mortar to experiment what kind of fats and oils had the worst effect on low-strength mortar; it went as follows. For rate of change in length of fat and oil soaking, there was an increase in the order of pig fat, bio-diesel, grape seed oil, and water; in the case of olive oil it was destroyed within 56 days. For rate of change in mass, there was an increase in the order of bio-diesel, water, pig fat, grape seed oil, and olive oil. For relative motion elastic coefficient, there was a decrease in the order of olive oil, grape seed oil, and water. On the whole, pig fat, bio-diesel, and olive oil were shown to have the worst effect on low-strength mortar.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.39 no.3
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• pp.303-307
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• 2006

The effects of starvation on histological changes in hepatocytes and the intestinal epithelium in the olive flounder, Paralichthys olivaceus were examined. The starved group was not fed for 12 weeks, whereas the fed group was given food. Food deprivation resulted in a significant decrease in hepatocyte nucleus size and nuclear height in the intestinal epithelium (P<0.05). In the starved group, pronounced degenerative changes were seen in the histology of hepatocytes and the intestinal epithelium; the tissue morphology was irregular and the nuclei were stained basophillic, shrunk irregularly, and very compact. These results suggest that histological changes in hepatocytes and the intestinal epithelium can be used as an indicator of starvation in the olive flounder. In addition, the data are interpreted in detail and some biologically important relationships are discussed.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2002.10a
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• pp.116-117
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• 2002

Olive flounder and Black rockfish comprises around 90％ of the total fish culture in Korea. Most of the olive flounder is consumed as raw fish meat “saengseonhoe”, as like a sashimi in Japan. Also, texture is particularly a important factor which determine the quality of raw fish meat in Korea. Many works have attempted to improve of texture such as arai, electrical stimulation and compulsory exercise of fishes. (omitted)

• Development and Reproduction
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• v.23 no.2
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• pp.149-160
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• 2019

This study examined the effects of different photoperiod conditions on olive flounder (Paralichthys olivaceus), a commercially important species in Korea. Daily variations in the expression of mRNA for the growth-related genes arylalkylamine N-acetyltransferase2 (AANAT2), preprosomatostatin1 (PSS1), and growth hormone (GH) were examined under a 12 h light:12 h dark photoperiod. All the genes were expressed at higher level during the dark period. Melatonin injections increased the expression of GH, but did not significantly affect the expression of PSS. Under short-day conditions (10 h:14 h), the fish gained more weight than under long-day conditions (14 h:10 h). A long nighttime induced melatonin secretion and increased the expression of GH mRNA, promoting weight gain in this species. Therefore, we thought that the long day condition in raising olive flounder may be effective in inducing body growth.

• Development and Reproduction
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• v.16 no.4
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• pp.301-307
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• 2012

Olive flounder Paralichthys olivaceus is one of the most widely cultured fish species in Korea. Although olive flounder receive attention from aquaculture and fisheries and extensive research has been conducted eye morphological change in metamorphosis, but little information was known to molecular mechanism and gene expression of eye development- related genes during the early part of eye formation period. For the reason of eyesight is the most important sense in flounder larvae to search prey, the screening and identification of expressed genes in the eye will provide useful insight into the molecular regulation mechanism of eye development in olive flounder. Through the search of an olive flounder DNA database of expressed sequence tags (EST), we found a partial sequence that was similar to crystallin beta A1 and gamma S. Microscopic observation of retinal formation correspond with the time of expression of the crystallin beta A1 and gamma S gene in the developmental stage, these result suggesting that beta A1 and gamma S play a vital role in the remodeling of the retina during eye development. The expression of crystallin beta A1 and gamma S were obviously strong in eye at all tested developing stage, it is also hypothesized that crystallin acts as a molecular chaperone to prevent protein aggregation during maturation and aging in the eye.

• Development and Reproduction
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• v.17 no.3
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• pp.231-240
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• 2013

Olive flounder (Paralichthys olivaceus) is one of the commercial important flatfish species in Korea. The ocular signal transduction pathway is important in newly hatched flounders because it is closely involved in the initial feeding phase thus essential for survival during the juvenile period. However, the study of gene expression during ocular development is incomplete in olive flounder. Therefore we examined the expression analysis of specifically induced genes during the development of the visual system in newly hatched flounders. We searched ocular development-involved gene in the database of expressed sequence tags (ESTs) from olive flounder eye and this gene similar to arrestin with a partial sequence homology. Microscopic observation of retinal formation corresponded with the time of expression of the arrestin gene in the developmental stage. These results suggest that arrestin plays a vital role in the visual signal transduction pathway of the retina during ocular development. The expression of arrestin was strong in the ocular system during the entirety of the development stages. Our findings regarding arrestin have important implications with respect to its biological role and evolution of G-protein coupled receptor (GPCR) signaling in olive flounder. Further studies are required on the GPCR-mediated signaling pathway and to decipher the functional role of arrestin.

• Development and Reproduction
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• v.14 no.2
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• pp.131-141
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• 2010

This study was conducted to examine the hematological factors in cultured olive flounder Paralichthys olivaceus depending on its growth stage and season. The study also aims at developing the standard hematological indicator for growth stage and season by examining total 16 parameters including whole blood (hematocrit, red blood cell and hemoglobin), biochemical (glucose, cholesterol, total protein, AST, ALT, $Na^+,\;K^+,\;Cl^-,\;Ca^{2+},\;Mg^{2+}$ and osmolarity), and endocrine (cortisol and $T_3$) factors in plasma of cultured olive flounder. The result showed a growth stage-dependent increase of $T_3$ level in olive flounder while the level of cholesterol showed an inverse correlation to fish size. For seasonal fluctuation in cultured olive flounder of the same growth stage, the highest level of Ht and RBC was observed in autumn.

• Applied Biological Chemistry
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• v.48 no.3
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• pp.217-221
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• 2005

This study was carried out to investigate the quality characteristics of white pan breads made with shortening and with olive oil by measuring moisture content, baking loss, specific loaf volume and rheological properties. Moisture contents of the white pan breads made with 4% and 6% olive oil were about 39.8% while those made with 4% shortening were $38.68{\pm}0.41%$. There were no signigicant differences in baking loss between the white pan bread made with 4% shortening, and those made with 4% and 6% olive oil. The specific loaf volume of the white pan bread made with 4% olive oil was 4.08 ml/g and the result showed lower value than that of the white pan bread made with 4% shortening. In terms of hardness and springness, there were no significant differences according to the sort and the amount of lipids, however white pan bread made without oil was the greatest in hardness.