• Journal of Aquaculture
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• v.18 no.2
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• pp.122-129
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• 2005

Ammonia is the major limiting factor in intensive aquaculture production systems. Therefore, quantification of ammonia excretion is important for the water quality management in aquaculture systems. Ammonia excretion is known to be affected by many factors such as body weight and dietary protein level (DPL). In this study, experiments were carried out to investigate the effects of body weight and DPLs on the rates of ammonia excretion of Nile tilapia Oreochromis niloticus. Three sizes of fishes (mean initial weight; 4.8 g,42.7 g and 176.8 g) were fed each of two dietary protein levels (30.5% and 35.5%). Daily feeding levels for the three fish sizes of 4.8 g, 42.7 g and 176.8 g were 6%, 3%, and 1.5% body weight per day, respectively. Each group of fish was stocked in a 17.1-L aquarium and all treatments were triplicated. Following feeding, the weight-specific ammonia excretion rate of O. niloticus increased, peaked at 4 to 8 h, and returned to pre-feeding levels within 24 h. Total ammonia nitrogen (TAN) excretion.ate per unit weight decreased with the increase of fish weight for each diet (P<0.05). The TAN excretion rate increased with increasing dietary protein content for each fish size (P<0.05). TAN excretion rates (Y) for each diet with different fish weights were described by the following equations: low DPL diet (30.5%): $Y\;(mg\;kg^{-1}\;d^{-1})=955.69-147.12\;lnX\;(r^2=0.95)$, high DPL diet (35.5%): $Y\;(mg\;kg^{-1}\;d^{-1})=1362.41-209.79\;lnX\;(r^2=0.99)$. Where: X=body weight (g wet wt.). The TAN excretion rates ranged 28.5%-37.1% of the total nitrogen ingested for the low DPL diet (30.5%) and 37.4-38.5% for the high DPL diet (35.5%). Total nitrogen losses of fish fed the high DPL diet $(35.5%;\;0.26\sim0.91g\;kg^{-1}\;d^{-1})$ were higher than those fed the low DPL diet $(30.5%;\;0.22\sim0.68g\;kg^{-1}\;d^{-1})$. The losses decreased per kg of fish as fish size increased. Results will provide valuable information fer water quality management and culture of Nile tilapia in recirculating aquaculture systems.

• Korean Journal of Food Science and Technology
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• v.29 no.5
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• pp.955-962
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• 1997

The food components of three kinds of edible ascidians being cultivated and caught in Tongyeong and Jisepo districts, Kyongnam of Korea were investigated. Wild Halocynthia roretzi (WM) and Pyura michaelseni (DM) were higher in contents of moisture and crude protein than cultured Halocynthia roretzi (CM). Total combined amino acid contents of CM, WM and DM muscles were 11,425.4 mg%, 11,595.4 mg% and 12,152.7 mg%, respectively, and major amino acids were Asp, Glu and Lys. The major fatty acids were 14:0, 16:0, 16:1n7, 18:1n7, 18:4n3, 20:5n3 and 22:6n3, and composition ratio of n3 polyunsaturated fatty acids of CM, WM and DM were 39.1%, 47.0% and 46.5%, respectively. In extracts components, total free amino acid contents of CM, WM and DM were 1,071.3 mg%, 1,278.7 mg% and 1,133.2 mg%, respectively, and the major amino acids were Tau, Glu, Pro, Asn, Gly, and Ala, while Arg was contained little quantities. As for nucleotides and related compounds, AMP was the principal component and IMP was detected though very small amounts in ascidian samples. Also contents of TMAO, total creatinine, betaine and peptide-N were $12.2{\sim}18.1\;mg%,\;15.5{\sim}19.6\;mg%,\;270.5{\sim}329.9\;mg%\;and\;62.0{\sim}111.0\;mg%,$ respectively. In inorganic ions of ascidian samples, the major components were $Na^+,\;K^+,\;Cl^-\;and\;PO^{3-}_4$.

• Korean journal of applied entomology
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• v.58 no.2
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• pp.133-142
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• 2019

This study analyzed genetic variation of the Oriental fruit fly (OFF), Bactrocera dorsalis, which is designated to be a quarantine insect pest in Korea. OFF samples endemic to Taiwan were collected at three different locations (Taipei, Taichung, and Kaohsiung) for three days from July 30 to August 1 in 2018 and assessed in their age and mitochondrial DNA sequence variations. In these places, 1,085 OFF males were collected using methyl eugenol lure while 30 males of Zeugodacus cucurbitae and one male of Bactrocera tau were collected using Cuelure. A protein diet lure attracted 6 flies including one OFF and 5 flies of Z. cucurbitae. Male heads of OFF contained pterin, which increased in contents with age from 32 to $59{\mu}g/head$. There was a local variation in pterin amounts in OFF heads, in which Kaohsiung population had lower amounts of pterin than Taipei and Taichung populations. Genetic distance among these three populations were measured by random amplified polymorphic DNA and showed that Taipei population was separated from Taichung/Kaohsiung cluster. Genetic variation was also analyzed in sequence variations in cytochrome oxidase I (CO-I) and NADH dehydrogenase I (ND-I). There was 7.8% variation in CO-I sequence (360 residues) and 6.6% variation in ND-I sequence (213 residues). These polymorphic sites are proposed to be used to develop SNP (single nucleotide polymorphism) markers characteristic to Taiwan OFF populations.

• Tuberculosis and Respiratory Diseases
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• v.49 no.3
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• pp.310-322
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• 2000

Background : Phospholipase C(PLC) plays an important role in cellular signal transduction and is thought to be critical in cellular growth, differentiation and transformation of certain malignancies. Two second messengers produced from the enzymatic action of PLC are diacylglycerol (DAG) and inositol 1, 4, 5-trisphosphate (IP3). These two second messengers are important in down stream signal activation of protein kinase C and intracellular calcium elevation. In addition, functional domains of the PLC isozymes, such as Src homology 2 (SH2) domain, Src homology 3 (SH3) domain, and pleckstrin homology (PH) domain play crucial roles in protein translocation, lipid membrane modificailon and intracellular memrane trafficking which occur during various mitogenic processes. We have previously reported the presence of PLC-${\gamma}1$, ${\gamma}2$, ${\beta}1$, ${\beta}3$, and ${\delta}1$ isozymes in normal human lung tissue and tyrosine-kinase-independent activation of phospholipase C-${\gamma}$ isozymes by tau protein and AHNAK. We had also found that the expression of AHNAK protein was markedly increased in various mstologic types of lung can∞r tissues as compared to the normallungs. However, the report concerning expression of various PLC isozymes in lung canærs and other lung diseases is lacking. Therefore, in this study we examined the expression of PLC isozymes in the paired surgical specimens taken from lung cancer patients. Methods : Surgically resected lung cancer tissue samples taken from thirty seven patients and their paired normal control lungs from the same patients, The expression of various PLC isozymes were studied. Western blot analysis of the tissue extracts for the PLC isozymes and immunohistochemistry was performed on typical samples for localization of the isozyme. Results : In 16 of 18 squamous cell carcinomas, the expression of PLC-${\gamma}1$ was increased. PLC-${\gamma}1$ was also found to be increased in all of 15 adenocarcinoma patients. In most of the non-small cell lung cancer tissues we had examined, expression of PLC-${\delta}1$ was decreased. However, the expression of PLC-${\delta}1$ was markedly increased in 3 adenocarcinomas and 3 squamous carcinomas. Although the numbers were small, in all 4 cases of small cell lung cancer tissues, the expression of PLC-${\delta}1$ was nearly absent. Conclusion : We found increased expression of PLC-${\gamma}1$ isozyme in lung cancer tissues. Results of this study, taken together with our earlier findings of AHNAK protein-a putative PLD-${\gamma}$, activator-over-expression, and the changes observed in PLC-${\delta}1$ in primary human lung cancers may provide a possible insight into the derranged calcium-inositol signaling pathways leading to the lung malignancies.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.8
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• pp.1398-1406
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• 2004

To develop the new type of salt-fermented seafoods, the salt-fermented oysters in olive oil (product SO) were manufactured, and food components and quality characteristics of product SO were examined. The optimum processing condition for product SO is as follows. The raw oyster with no shell was washed off with 3% saline solution. Then dewatered, and dipped in the brine-salting solution made up with saturated saline solution and oyster sauce (2 : 1 v/v) mixture added 1% sodium erythorbic acid and 0.2% polyphosphate. After salt-fermentation it ripened by brine salting at 5$\pm$1$^{\circ}C$ for 15 days. Then dried at 15$^{\circ}C$ for 4 hours with cool-air, and packed in No. 3B hexahedron type can. Finally, poured with olive oil and seamed it by double-seamer. The moisture, crude protein, crude ash and volatile basic nitrogen contents of the product SO were 61.6%, 12.0%, 16.3% and 34.3 mg/100 g, respectively. In taste-active components of the product SO, total amount of free amino acids is 2,335.4 mg/100 g and it has increased by 50% overall during salt-fermentation 15 day. Taurine, glutamic acid, proline, glycine, alanine, $\beta$-alanine and lysine were detected as principal free amino acids. The contents of inorganic ions were rich in Na and K ion, while the amounts of nucleotide and its related compounds and other bases except betaine were small. From the results of this research, the product SO had a superior organoleptic qualities compared with conventional oyster product, and could be reserved in good conditions for storage 90 days at room temperature.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.23 no.2
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• pp.178-184
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• 1990

The lipid components, nitrogenous extracts and amino acids of dark muscle(DM) of ski-pjack (Katsuwonus pelamis) were analyzed and compared with those of white muscle (WM). WM was higher in moisture and crude protein content, and lower in crude lipid and ash content than those of DM. Contents of volatile basic nitrogen in WM and DM were 22.7mg/100g and 46.9mg/100g. Total lipid(TL) of WM and DM consisted of $79.7\%,\;71.9\%$ neutral lipid(NL), $6.8\%,\;9.5\%$ glycolipid(GL), and $13.5\%,\;18.6\%$ phospholipid(PL), respectively NL was mainly com-posed of free fatty acid, triglyceride, and PL was mainly occupied by phosphatidyl ethanolamine, phosphatidyl choline. Also Iysophosphatidyl choline and Iysophosphatidyl ethanolamine were identified in PL. In fatty acid composition of TL, NL, GL and PL, WM revealed higher contents in saturates and monoenes such as 16 : 0, 18 : 1, while DM showed higher contents in polyenes such as 22 : 6 especially. The major fatty acids of these samples were generally 16: 0, 18:0, 18:1, 20:5 and 22 : 6. Contents of total free amino acids from WM and DM were 5,982.3mg/100g and 4,450.7 mg/100g (dry base). Of free amino acids, Tau concentration was much higher in DM than in WM, Ala, Gly, Met, Arg, Thr were also high in DM. But His was much higher in concentration in W. Content of inosinic acid(IMP) in WM(680.9mg/100g) was higher than that of DM(73.1mg/100g). The degradations of IMP proceeded very rapidly in DM. DM contained much higher trimethylamine oxide and trimethylamine than those of WM. The profile of combined amino acids in these samples, were very similar, and main amino acids were Glu, Asp, Lys, Ala, Ile and Arg.

• Journal of the Korean Society of Food Science and Nutrition
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• v.32 no.8
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• pp.1186-1192
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• 2003

The food components and quality characteristics of two kinds of boiled-dried anchovies (Engraulis japonica) in the Korean market such as the Jukbang-Myoel (JM) and Kwonhyunmang-Myeol (KM) were investigated. KM was higher in moisture content, and lower in crude protein and lipid contents than JM. Volatile basic nitrogen was higher in KM than in JM, whereas TBA value showed higher levels in JM. Total combined amino acid contents of KM and JM were 41.9∼46.6 g/100 g and 42.0∼49.2 g/100 g, respectively, and large sized boiled-dried anchovies revealed higher contents than small sized ones in both samples. Their major amino acids were Glu, Asp, His, Leu, Ala and Arg. Total lipids of KM and JM were consisted of 55.4 ∼ 68.4%, 53.0 ∼ 68.0% neutral lipid and 31.6∼44.6%,32.0∼47.0% polar lipid, respectively, and their major fatty acids were 14:0, 16:0, 16:1n-7, 18:1n-9, 20:5n-3 and 22:6n-3. In taste compounds of boiled-dried anchovies, free amino acid contents of Km and JM were 953.7 ∼ 1,044.8 mg/100 g and 968.8 ∼ 1,306.4 mg/100 g, respectively, and main free amino acids were Tau, His, Ala, 1-methyl his, Lys, Glu and Gly. The contents of other taste-active components such as IMP, total creatinine, TMAO and inorganic ions were not significantly different between KM and JM. The results of sensory evaluations for organoleptic characteristics, small sized JM showed no difference in sensory qualities, whereas large sized JM showed good qualities for appearance, taste and odor compared with KM.