• Research in Plant Disease
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• v.7 no.3
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• pp.155-163
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• 2001

Two attenuated Cucumber mosaic virus (CMV) isolates, Paf-CMV and Rs2-CMV that had been selected from CMV isolates associated with satellite RNA (satRNA) were tested for cross-protection effect in pepper plants. The viruses selected as attenuated strains appeared to be identical serologically and physically to the challenge virus (Mf-CMV), but they were lower in the dilution end-point of infectivity of crude sap than Mf-CMV When symptoms were observed in several indicator plants after inoculation, Paf-CMV and Rs2-CMV were symptomless or showed mild mosaic symptoms while another satRNA isolate Ap-CMV developed severe mosaic symptoms on the leaves as Mf-CMV. The nucleotide sequences of the satRNAs were determined by sequencing full-length cDNA clones. Paf-, Rs2- and Ap-satRNAs were 386, 335, and 347 nucleotides long, respectively, The sequences were then compared with the other known Y-satRNA, revealing that nucleotide sequences of the satRNAs consisted of 5'- and 3'-terminal conserved regions. However variations occurred on the middle regions of the sequences, especially those related to symptom interference, showing significant differences between Paf-satRNA and other isolates. Infectious transcripts of Paf-satRNA and Rs2-satRNA induced mild mosaic symptoms in pepper plants when supported by genomic RNAs of Mf-CMV. Under greenhouse conditions, Paf-CMV and Rs2-CMV were tested for cross-protection effect in pepper and tobacco (Nicotiana tabacum cv, Xanthi nc) plants against Mf-CMV. No symptoms were developed on the plants vaccinated with Paf-CMV until 3 weeks after inoculation with the virulent strain; however another attenuated isolate, Rs2-CMV, showed less effectiveness in cross-protection. Depending on the concentration of the challenged virus, symptoms sometimes appeared later in the upper leaves. However, in plants challenged with low concentrations (below 0.2 mg/ml) of the challenge inoculum, symptoms caused by the virulent strain did not develop on the plants vaccinated with Paf-CMV. In the field experiments, the number of pepper plants with severe mosaic symptoms in the control plots was progressively increased after transplanting and reached approximately 50% after 50 days. On the other hand, the incidence of mosaic disease appeared very low on the plants that had received the protective inoculation with Paf-CMV.

• Proceedings of the Korean Society for Food Science of Animal Resources Conference
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• 2000.11a
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• pp.59-75
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• 2000

This study was carried out to develop a DNA marker for identifying between Korean cattle (Hanwoo) and other breeds. First experiment was performed to isolate Hanwoo specific DNA marker at sequence characterized amplified regions (SCARs). Five breeds of cattle including Hanwoo, Holstein, Hereford, Angus and Charolais were represented with the from 8 to 20 individuals. Fourteen primers of 300 arbitrary primers of 10 nucleotides showed reproducible polymorphism across the breeds. An amplified band of 0.9 kb in the primer MG-3 showed the specificity to Holstein breed. And MG-6 and MG-12 detected the Hereford and Hanwoo specific markers at the size of 2.0 kb and 1.0 kb, respectively. A 1.0 kb band of MG-12 was cloned and sequenced. A SCAR primer was designed based on the obtained sequences. It was possible to identify the Hanwoo from Holstein breed. Second experiment was carried out to observe the genotype frequencies of MC1R in 1,044 samples of imported beef and eight different cattle breeds including Hanwoo, Holstein, Angus, Brown-Swiss, Charolais, Limousin, Simmental and Hereford. The primers for the amplification of bovine MC1R gene were designed based on a bovine MC1R gene sequence (GenBank accession no.Y19103). A size of 350 bp was amplified by polymerase chain reaction(PCR), digested with two different restriction enzyme, BsrFI and MspA II, and electrophoresed in 2.5% Metaphore agarose gel for determination of genotypes. Genotype frequencies of Hanwoo were 0.10 in E+e and 0.90 in ee. Allele ED was shown in all of Holstein and Angus breeds tested which have black coat color phenotypes. We suggested that SCAR marker and the bovine MC1R gene could be used as a DNA marker for distinguishing beef between Hanwoo and Holstein.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.22 no.1
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• pp.25-35
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• 1989

To prepare a new type of fish sauce from skipjack scrap, it was examined the effect of koji on the sauce flavor, conditions of low salt fish sauce processing and the changes of taste com-pounds during its fermentation. To prepare the skipjack scrap sauce, chopped skipjack head paste was mixed with $6.6\%$ skipjack viscera, $26.9\%$ koji, $71\%$ of $25\%$ brine, $13.3\%$ salt and $7.6\%$ glucose, and fermented at $25\pm4^{\circ}C$ for 90 days. The same process was also carried out to prepare the low salt skipjack scrap sauce adding $7.6\%$ sorbitol, $0.3\%$ lactic acid and $9.8\%$ ethyl alcohol instead of $13.3\%$ salt. The major free amino acids in the products were glutamic acid, Iysine, valine, phenylalanine, alanine, leucine and isoleucine at 90 days of fermentation. And the contents of total free amino acids in both products were 3,307mg/00m1, 3,637.1mg/100m1 at 90 days of fermentation. The predominating non-volatile organic acids showed in the products were lactic acid, succinic acid, pyroglutamic acid, which were $90\%$ over contents of the total non-volatile organic acids. Total non-volatile organic acid contents in both products were 1,002.1mg/100ml, 1,312.9mg/100m1 at 90 days of fermentation. During fermentation of sauce, ADP, AMP and IMP were decreased, while inosine and hypoxanthine were increased. The major taste compounds of the products were rove진ed free amino acids and non-volatile organic acids. The nucleotides and their related compounds, total creatinine, betaine, TAMO and sugar were seemed to be having an auxiliary role in taste of those products. Fishy odor in skipjack scrap sauce can be improved by adding koji. And the low salt skipjack scrap sauce ($9.12\%$ of salt contents) can be prepared by the replacement of a part of salt with sorbitol, lactic acid and ethyl alcohol. From the results of sensory evaluation and chemical experiments, the skipjack scrap sauce products supposed to be at least equal to the sold soy sauce on the market in quality.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.14 no.4
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• pp.201-211
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• 1981

For the effective utilization of sardine, sardinops melanosticta, one of the major coastal fish in Korea, of which annual catch has been increasing from year to year since 1970, it was processed in form of fermented fish paste. The fish were treated with BHA and Teaox-Ⅱ in concentration of $0.01\%\;and\;0.02\%$ to prevent the oxidation of lipid during fermentation and then salted with $20\%$ table salt and fermented at room temperature of $25\pm3^{\circ}C$. The duration of fermentation necessary for the final product with an acceptable taste was determined by sensory evaluation by means of profile method. From the result of sensory evaluation, one month was found to be suitable as the reasonable duration of fermentation. Both BHA and Tenox-Ⅱ in conceatration of $0.02\%$showed a good preventing effect on the lipid oxidation during fermentation. In case of fermented sardine treated with both antioxidants, lipid oxidation occurred little up to two months, whereas the control showed a remarkable deterioration during one month of fermentation. Most of the nucleotides in sardine was decomposed from adenosing triphosphate to inosine and hypoxanthine during the fermentation of one month. The great portion of free amino acids in the extractives of product was occupied by leucine, glutamic acid, isoleucine, alanine, valine and ysine in turn, and their coatent was $59.4\%$ of the total free amino acids. The amount of essential amino acids was $59.4\%$ of the total free amino acids. The contents of 5'-IMP, betaine, trimethylamine oxide and total creatinine in the extractives of product were $1.9{\mu}mole/g,\;4.9mg\%,\;1.0mg\%\;and\;475mg\%$, respectively. According to the omission test, the main constituents of the characteristic taste of fermented sardine could be assumed as free amino acids and a little amount of 5'-IMP.

• Journal of Aquaculture
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• v.20 no.1
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• pp.51-55
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• 2007

This study was conducted to evaluate the muscle quality of the olive flounder fed on extruded pellet (EP) diets compared with a raw fish moist pellet (MP) diet for olive flounder, Paralichthys olivaceus in a commercial scale for a year. The sensory and physical qualities and palatable compounds were compared for evaluation of muscle quality in fish. Four diets were formulated for this experiment: two experimental EP diets (EP 1 and 2), one commercial EP diet (CEP) and MP diet. Crude lipid of fish fed EP1 and EP2 was significantly higher (P<0.05) than that of fish fed CEP, but not significantly different from that of fish fed MP (P>0.05). In the palatable compounds, the free amino acids composition were much alike in that of all the diets. Proline, glycine and alanine from fish fed diet EPs were the most abundant compound among amino acid compositions. There was little difference in the free amino acid compositions of all flounder from localities and the growing conditions between wild and cultured fishes. Taurine of fish fed EP1 was dominantly high over that of fish fed EP2, CEP and MP. In all nucleotides and their related compounds, ATP and IMP from fish fed EP diets were higher (P<0.05) than those of fish fed MP. In the sensory score, overall-acceptability of fish fed EP2 were significantly higher (P<0.05) than that of fish fed EP1, CEP and MP. Hardness of physical properties from fish fed EP2 was significantly higher (P<0.05) than those of fish fed CEP (P<0.01). These results strongly suggest that diets EP could be developed to replace MP diet for the grow-out stage of olive flounder without adverse effect on growth performance.

• Food Science and Preservation
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• v.18 no.5
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• pp.729-738
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• 2011

This study was conducted to investigate the effect of extruded pellets (EP) containing different levels of protein (51%-55%) and lipid (9%-15%) on flesh quality of flounder (Paralichthys olivaceus) comparing with raw fish-based moist pellet (MP). Two replicate groups of 40 fish per each tank (initial mean weight 106 g) were fed one of three experimental EP (EP1, EP2 and EP3) containing different protein and lipid levels, a commercial EP (EP4) and MP for 16 weeks. Moisture content of fish fed MP was significantly higher than that of fish fed all EP. Significantly higher contents of 16:1n-7, 20:4n-6, 20:5n-3 and lower 18:2n-6 were observed in fish fed EP4 and MP compared with fish fed EP1, EP2, EP3. The 22:6n-3 content was not significantly different among all groups. Taurine content of fish fed MP was significantly higher than that of fish fed all EP. Asparagine content of fish fed EP1 was significantly higher than that of fish fed EP2, EP, EP4 and MP. Significant difference were observed in lysine and serine contents of fish fed experimental diets. In nucleotides and their related compounds, ATP and AMP content was not affected by diets. Significant difference were observed in IMP contents of fish fed experimental diets. Textural properties, no significant difference was observed among the fish groups fed different diets.

• 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 Food Science and Technology
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• v.26 no.4
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• pp.382-388
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• 1994

Because of its restrictive harvest from spring to summer, It is necessary to preserve raw ascidians, Halocynthia roretzi, for the purpose of processing regardless of season. We evaluated low Temperature tolerance of ascidian and conditions for cold storage to secure the quality of the stock. To retard the browning of meat rapidly occurred after sucking, ascidians were blanched for 10 seconds in 10% boiling salt solution or dipped for 60 seconds in 0.2% $NaHSO_3$ solution, respectively. The samples were stored in ice, at $-17^{\circ}C$ or $-35^{\circ}C$ for 85 days, respectively. Changes in VBN, glycogen, brown pigment formation, total carotenoid, nucleotides and their related compounds during the storage were determined, and sensory evaluation of quality was also practiced. VBN and brown pigment formation were rapidly increased. Glycogen was gradually decreased and then not detectable after 85 days in case of ice storage. Lipophilic brown pigment was higher than hydrophilic and rapidly increased during storage. The result of sensory evaluation showed that the ascidian treated in 0.2% $NaHSO_3$ was good for 85 days of storage at $-35^{\circ}C$ . Judging from the results of chemical experiment and sensory evaluation, the quality of ascidian treated in 0.2% $NaHSO_3$ and stored at $-35^{\circ}C$ was better than that of other samples.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.34 no.3
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• pp.260-267
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• 2001

The biochemical composition and antioxidative activity of marine microalgae were investigated for the effective utilization of marine resources. Two species of marine microalgae, Nannochloris oculata (N. oculata) of Chlorophyceae and Phaeodactylum tricornutum (P. tricornutum) of Bacillariophyceae, were selected. Because these species showed the high growth rate and easy to continuous culture. The contents of crude protein, lipid, and carbohydrate were $54.91\%,\;11.29\%,\;and\;10.15\%$, for N. oculata and $38.07\%,\;13.19\%,\;and\;7.13\%$, for P. tricornutum, respectively. Glutamic acid was the highest concentration for both species. Galactose (3,712.02 mg/100g), fucose (1,966.03 mg/100g), and glucose (1,814.35 mg/100g) were the major carbohydrates for N. oculatae, and glucose (5,295.45 mg/100g) and mannose (841.34 mg/100g) were for P. tricornutum. K (12,906.86 mg/100g), Mg (1,039.15 mg/100g), Ca (882.57 mg/100g) and Fe (747.20 mg/100g) were the major minerals for N. oculata, and K (11,718.65 mg/100g), Ca (2,003.32 mg/100g), Mg (1,570.84 mg/100g) and Fe (552.58 mg/100g) were for P. tricornutum. In the composition of nucleotides, ADP ($4.77{\mu}mol/g$) was the highest in N. oculata and hypoxanthine (11.74{\mu}mol/g) in P. tricornutum. Large amount of linoleic acid (18: 2, $\omega-6$) was contained in N. oculata. In contrast 16: 1 ($\omega-7$) and 20: 5 ($\omega-3$) were major fatty acid in P. tricornutum. The antioxidative activities of organic solvent extracts of two microalgae were measured by the 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay method. The chloroform extract obtained from P. tricornutum was identified to be the most effective in DPPH radical scavenging activity.

• Journal of the Korean Society of Food Science and Nutrition
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• v.9 no.1
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• pp.23-32
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• 1980

This study was attempted to establish the basic data for evaluating taste compounds in fermented entrails of Clupanodon Osdeckii. The changes of such compounds as amino acids, nucleotides and their related compounds, betaine, TMAO and TMA during fermentation were analyzed. IMP, AMP, ADP and ATP were decreased, while hypoxanthine was increased during the fermentation. The content of hypoxanthine in fermented entrails of Clupanodon Osdeckii after 50 days was increased to about 2 times of that in raw entrails. In the free amino acid composition of raw entrails, abundant amino acids were lysine, glutamic acid, valine, alanine, threonine, serine, leucine and glycine in order. Such amino acids as arginine, tyrosine and phenylalanine were lower than 2.0% of total free amino acid, and proline and cysteine were detected in trace amount. The changes in free amino acid composition of the extract in entrails of Clupanodon Osdeckii during fermentation were not observed. Such amino acids as lysine, glutamic acid, valine, serine and leucine were especially abundant in both raw and fermented products. The content of total free amino acids in fermented entrails of Clupanodon Osdeckii after 50 days were increased to about 12 times of that in raw. The content of betaine nitrogen were about 14.5 (moisture and salt free base) after 50 days of fermentation. TMAO nitrogen was decreased during the fermentation. It is believed that lysine, glutamic acid, valine, serine, leucine and hypoxanthine play an important role as taste compounds in fermented entrails of Clupanodon Oseckii.