• Korean journal of food and cookery science
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• v.13 no.4
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• pp.448-452
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• 1997

Sensory and physical qualities and palatable compounds of cultured flounder muscle were compared with the wild ones. No differences were seen in the contents of the moisture, lipid, protein between cultured and wild dorsal muscles, however, sensory panels preferred the wild fish to cultured ones because of the texture and taste of wild fish, and they could differentiate the degree of difference in the texture and taste property distinctly. Raw meat of the wild fish was harder and more elastic than the cultured ones, however, the cultured meat was harder and drier than the wild ones once they were cooked. The results of physical properties were similar to the results of sensory evaluation. Alanine was the most abundant compound among the free amino acids which make meat palatable and followed by glutamic acid, proline, methionine, and glycine. There was no difference in total content of free amino acids between two fish muscles. ATP was the most abundant among all nucleotides and their related compounds in both fish muscles followed by IMP, ADP, AMP, however, the total content of those was greater in wild fish muscle (9.4 ${\mu}$mole/g) than in cultured fish muscle (6.7 ${\mu}$mole/g).

• Korean Journal of Food Science and Technology
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• v.20 no.6
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• pp.873-877
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• 1988

Nitrogenous extractives and amino acids were analyzed with the dorsal muscle from wild and cultured bastard(Paralichthys olivaceus), and flounder (Pleuronichthys cornutus). Cultured bastard was higher in moisture content, and lower in crude lipid and protein content than those of wild one. Contents of free amino acids from wild and cultured bastard, flounder were 305.03mg/100g, 253.42mg/100g, and 340.10mg/100g, respectively. The profile of free amino acids in these samples was very similar, although there were a relatively difference in glycine, threonine, proline contents. Content of IMP in wild bastard (408.31mg/100g) and cultured one (356.26mg/100g) were higher than that of flounder (178.61mg/100g). Wild bastard contained higher trimeth-ylamine oxide and total creatinine than cultured one. Total amino acid contents of dorsal muscle from wild and cultured bastard, and flounder were 21.94g/100g, 20.12g/100g, and 17.63g/100g, respectively. The major amino acids of these samples were glutamic acid, aspartic acid, leucine and isoleucine.

• Journal of the Korean Society of Food Science and Nutrition
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• v.25 no.4
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• pp.637-642
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• 1996

This study was carried out to investigate the change of palatability improvement of cooked meat by the physico-chemical properties and sensory characteristics as aging at $3^{\circ}C$ after thawing of frozen Holstein tenderloin. Shear force value(SFV), myofibrillar fragmentation ratio(MFR), appearance of 30ki1o dalton (30KD) component, raw meat aroma, tenderness, palatability of cooked meat, content of free amino acid and ATP related compound were measured. Raw meat aroma (p< 0.01), tenderness(p<0.05), SFV(p<0.05), MFR(p<0.01) and 30KD(p<0.001) of unfrozen beef tenderloin aged at $3^{\circ}C$ were superior than frozen beef tenderloin. As aging at $3^{\circ}C$ after thawing of frozen beef tenderloin SFV(p<0.05) decreased, MFR(P<0.001) and 30KD(p<0.001) increased, and raw meat aroma and tenderness improved(p<0.05). Also, cooked meat aroma, texture and palatability improved(p<0.05), without changing the taste. The content of aspartic acid and leucine of tenderloin aged thawing of frozen beef abounded were more than frozen beef(p<0.05), concentration of IMP(P<0.05) decreased, the hypoxanthine(p<0.05) and inosine increased.

• Microbiology and Biotechnology Letters
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• v.8 no.1
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• pp.1-8
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• 1980

Changes of nucleic acid related substances and their enzymes during rice makkulli koji making were observed and enzymological properties of crude enzymes were examined. The results obtained were as follows : (1) The amounst of acid soluble phosphorus were increased, while no remarkable changes were observed in the component of total phosphorus during koji making. (2) AMP and IMP were increased, while ADP and ATP were decreased gradually in the course of process. (3) Activities of nucleic acid degrading enzymes were increased with the lapse of time. (4) In the crude enzyme solution extracted from rice makkulli koji, the optimal pH of RNase was 4.0~5.0 and those of PDase PNase were 5.0. (5) RNase and PMase were stable at the range of pH 4.0~5.0 and PDase was stable at the pH 4.0. (6) The optimal temperature of RNase was 55$^{\circ}C$, and that of PDase was at the range of 50~55$^{\circ}C$, and 5$0^{\circ}C$ for PMase. (7) Among the three enzymes, the heat stability was in order RNase, PDase and PMase, and especially PMase was so heat labile that it was almost inactivated at 7$0^{\circ}C$ for 10 min. (8) Inhibition by metal ions and other inhibitors was disclosed : C $u^{++}$ and Z $n^{++}$ inhibited the activity of RNase, and C $u^{++}$, NaF and N $a_2$HP $O_4$ inhibited that of PDase, while C $u^{++}$ and NaF inhibited the PMase activity.ctivity.

• Korean Journal of Food Science and Technology
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• v.22 no.2
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• pp.221-226
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• 1990

Fish flesh of Alaska pollack containing 5% of corn starch were fermented with 8 strains of mold and monitoring of their flavor characteristics, acceptability, nucleotides and their related compounds, amino acid compositions were conducted. All strains were grown vigorously on fish flesh media and formed their characteristic spores with unique flavor by strains. Amino type nitrogen $(NH_2-N)$ content of fermented fish flesh (FFF) were 25-26 times higher than that of raw flesh and 6-15 times higher in extractable nitrogen (Ex-N) content . The strains which produce more ADP (Adenosine 5'-diphosphate) in FFF also showed much higher level of IMP (Inosine 5'-monophosphate) and GMP (Guanosine 5'-monophosphate) content than that of raw flesh. Amino acid composition were differ by strain but lysine was generally highest and arginine, glutamic acid, leucine and alanine in order In review of sensory evaluation , total content of nucleotides, $NH_2-N$, Ex-N and amino acid compositions, suitable strains for fish flesh fermentation were Aspergillus oryzae KFCC 11371, Asp. oryzae KFCC 32343, Penicillium roqueforti KFCC 11269 and Asp. quercinus.

• Asian-Australasian Journal of Animal Sciences
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• v.28 no.11
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• pp.1629-1640
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• 2015

This study was performed to compare carcass traits, sensory characteristics, physiochemical composition, and contents of nucleotides, collagen, and free amino acids among quality grades (QG) and to understand the association between QG and above parameters in loin and rump of Korean cattle steer. Loin and rump samples were obtained from 48 Korean cattle steers with each of four QG (QG 1++, 1+, 1, and 2; average 32 months of age). Carcass weight and marbling score (MS) were highest in QG 1++, whereas texture score measured by a meat grader was highest in QG 2. A correlation analysis revealed that MS (r = 0.98; p<0.01) and fat content (r = 0.73; p<0.01) had strong positive correlations with QG and that texture had a strong negative correlation (r = -0.78) with QG. Fat content in loin was highest but protein and moisture contents were lowest in QG 1++. Our results confirmed that a major determinant of QG is the MS; thus, intramuscular fat content. The International Commission on Illumination $L^*$, $a^*$, and $b^*$ values in loin were highest in QG 1++. Numeric values of shear force in loin were lowest in QG 1++, whereas those of tenderness, juiciness, and overall acceptability tended to be highest in QG 1++ without statistical significance. QG was strongly correlated with juiciness (r = 0.81; p<0.01) and overall acceptability (r = 0.87; p<0.001). All sensory characteristics were higher (p<0.05) in loin than those in rump. Adenosine-5'-monophosphate (AMP) and inosine-5'-monophosphate (IMP) contents in both loin and rump did not differ among QGs. No nucleotide (AMP, IMP, inosine, hypoxanthine) was correlated with any of the sensory traits. Total, soluble, and insoluble collagen contents in loin were higher in QG 1++ than those in QG 1. All three collagens had lower content in loin than that in rump. All three collagens were positively correlated with tenderness, juiciness, and overall acceptability. Glutamic acid content did not significantly differ among the four QGs in either loin or rump. In conclusion, it is confirmed that QG is associated with sensory traits but nucleotide contents in beef may not be a major factor determining meat palatability in the present study.

• Journal of Microbiology and Biotechnology
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• v.17 no.10
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• pp.1733-1737
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• 2007

A total of 2,280 nonduplicate clinical isolates of Pseudomonas aeruginosa, obtained nationwide from Korean non-tertiary care hospitals from 2002 to 2005, were identified and their susceptibilities to aminoglycosides, antipseudomonal penicillins, carbapenems, cephalosporins, monobactams, and quinolones were studied, together with their production of ${\beta}$-lactamases. Using disk diffusion and minimum inhibitory concentration tests, it was found that 2.9% of isolates were multidrug-resistant (MDR) P. aeruginosa. An EDTA-disk synergy test, PCR amplification with specifically designed primers, and direct sequencing of the PCR products showed that the $bla_{OXA-10}$, $bla_{VIM-2}$, $bla_{OXA-2}$, $bla_{OXA-17}$, $bla_{PER-1}$, $bla_{SHV-12}$, and $bla_{IMP-1}$ genes were carried by 34.3%, 26.9%, 3.0%,3.0%, 1.5%, 1.5%, and 1.5% of 67 MDR P. aeruginosa isolates, respectively. The prevalence of MDR P. aeruginosa was three-fold higher, compared with that from the United States. More than two types of ${\beta}$-lactamase genes were carried by 10.4% of isolates. The most prevalent ${\beta}$-lactamase genes were $bla_{VIM-2}$ and $bla_{OXA-10}$. This study is the first description of MDR P. aeruginosa trom non-tertiary care hospitals in Korea and the coexistence of the $bla_{VIM-2}$, $bla_{IMP-1}$, or $bla_{PER-1} in these clinical isolates.

• Journal of Korean Society of Environmental Engineers
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• v.30 no.11
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• pp.1087-1094
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• 2008

Diazinon is a phosphorothiate insecticide widely used in the world including Korea. This study investigates the feasibility of photolysis and photocatalysis processes for the degradation of diazinon in water. Both photolysis and photocatalysis reactiosn were effective in degrdading diazinon, however lower TOC removals were achieved. In case of photocatalysis, approximately 40% of nitrogen from diazinon was recovered as NO$_3^-$, and less than 5% of phosphorus as PO$_4{^{3-}}$. However, the sulfur in diazinon molecule was completely recovered to SO$_4{^{2-}}$ from photocatalysis reaction, and the recovery from photolysis was 50%, indicating that P=S bond easily breaks first during photolysis and photocatalysis. The poor recoveries of ionic byproducts and TOC from photolysis and photocatalysis indicate the presence of other organic intermediates during reactions. The formation of organic intermediates were identified during reactions using GC/MS and LC/MS/MS, and the main degradation products were diazoxon, and 2-isopropyl-4-methyl-6-hydroxypyrimidine (IMP), respectively. Finally, the acute 48-hr toxicity test using Daphnia magna were employed to measure the toxicity reduction during photocatalysis of degradation. The results showed that the toxicity increased until 180 min of the photocatalysis reaction (from EC$_{50}$ (%) of 69.6 to 13.2%), however, acute toxicity completely disappeared (>100%) after 360 min. The toxicity results showed that the intermediates from photocatalysis such as diazoxon were more toxic than diazinon itself, however these intermediates can be degraded or mineralized with further reaction.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.33 no.2
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• pp.98-102
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• 2000

To investigate quality characteristics of southeast asian salt-fermented fish sauces, various chemical properties were examined against 13 kinds of southeast asian salt-fermented fish sauces. The range of chemical compositions were $60.6{\~}72.8{\%}$ moisture, $18.2{\~}25.8{\%}ash,\;0.9{\~}13.7{\%}$ crude protein and $14.1{\~}338.6\;mg/100 ml$ VBN. The pH and salinity were $4.66{\~}5.91,\;24.1{\~}30.6{\%}$, respectively. Total nitrogen, amino nitrogen, total free amino acid, and total ATP related compounds (sum of $ATP{\~}IMP$, HxR, Hx and uric acid) were in the ranges of $0.140{\~}2.199g,\;115.4{\~}1,643.0 mg,\;46.4{\~}9,056.3\;mg\;in\;100 ml,\;and\;0.829{\~}9.564 {\mu}mol\;in\;1\;ml$, respectively. Southeast asian salt-fermented lish sauces were rich in tree amino acids, such as glutamic acid, Iysine, leucine, alanine, aspartic acid, valine and isoleucine in the order.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.32 no.3
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• pp.252-255
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• 1999

The quality characteristics of the Korean traditional salt-fermented fish sauces, the traditional anchovy sauce (TAS) and the sandlance sauce(TKS) were evaluated comparing to the commercial anchovy sauce (CAS) and sandlance sauce (CKS). The acidity was higher in TKS than in TAS, whereas the contents of VBN, total-N and amino-N were higher levels in TAS. In color values, L and b values in TAS were generally higher than those in TKS, whereas a and ${\Delta}E$ values were higher in TKS. The contents of total free amino acids in TAS and TKS were $12.40\;g\%$ (w/v) and $9.549 g\%$ (w/v), respectively. The contents or six amino acids, alanine, glutamic acid, leucine, isoleucine, valine and Iysine were higher in TAS, whereas the contents of arginine, glutamic acid, leucine, alanine and valine were higher in TKS. Nucleotides such as IMP and hypoxanthine were principal components in both TAS and TKS. The nitrogen related compounds, TMAO, TMA and total creatinine were determined to be $108.8\;mg\%$ (w/v), $60.5\;mg\%$ (w/v), $62.4\;mg\%$ (w/v) in TAS, and those in TKS were $60.1\;mg\%$ (w/v), $24.1\;mg\%$ (w/v), $67.6\;mg\%$ (w/v), respectively.