• Korean Journal of Fisheries and Aquatic Sciences
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• v.20 no.5
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• pp.431-440
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• 1987

In order to develop a new type of food source for the effective utilization of fish protein, plastein reaction was applied to improve the functional properties of filefish protein. Plasteins were synthesized from a peptic filefish protein hydrolysate by papain, pepsin, $\alpha-chymotrypsin$ and protease(from Streptomyces griceus) under the optimum conditions of previous paper). Also, L-glutamic acid diethylester and L-leucine ethylester were incorporated into plastein during the plastein reaction by papain. And, General composition, yield, molecular weight, amino acid composition, color and IR spectrum of plasteins were measured. The protein, ash and lipid content of the plasteins were $72\~78\%,\;7.4\~11.8\%\;and\;0.3\~0.9\%$ respectively. The yield of plasteins were papain $55.0\%,\;pepsin\;47.6\%,\;\alpha-chymotrypsin\;38.3\%,\;protease\;23.6\%$, glutamic acid-incorporated plastein (Glu-Plastein) $35.0\%$, and leucine-incorporated plastein (Leu-plastein) $45.7\%$. The glutamic acid and leucine content in Glu-plastein and Leu-plastein were $38.7\%,\;41,7\%$, respectively, while the contents in the peptic filefish protein hydrolysate were $16.01\%\;and\;8.16\%$, respectively. The amino acid compositions were similar to that of the original filefish muscle protein. The major molecular weights of the peptic hydrolysate estimated by gel filteration were 2,000 and 310, and those of plasteihs were 21,000 and 4,900 for papain, 24,000 for pepsin, 18,500 for $\alpha-chymotrypsin$ 6,700 for protease, 24,000 for Glu-plastein and 17,000 for Leu-plastein. The structural changes in freeze-dried filefish meat, the FPC and hydrolysate were not observed on the IR spectrum. But plasteins showed amide I band in $1,600\~l,700cm^{-1}$ range and resulted in a strong band in $800\~850\;cm^{-1},\;700\~750\;cm^{-1}\;and\;650\~700\;cm^{-1}$. The amide I band of Glu-plastein was wider than those of other plasteins and had also a small band at $1,440\;cm^{-1}$.

• Food Science of Animal Resources
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• v.27 no.3
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• pp.320-328
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• 2007

This study was conducted to determine the effect of pH adjustment and the addition of cryoprotectants on the quality characteristics of chicken breast surimi. We prepared surimi from Alaska pollack, as a the control, by two time washing times and the addition of cryoprotectants. Different preparations of surimi were manufactured by adjusting to pH 11.0 and the addition of different addition cryoprotectants during frozen storage (T1 : 5% sorbitol and 0.3% polyphosphate, T2: 4% sugar, 5% sorbitol and 0.3% polyphosphate, and T3: 2% salt, 4% sugar, 5% sorbitol and 0.3% polyphosphate). The moisture content was significantly lower in the control and T3 samples. The crude protein content was increased with storage times. The crude protein was higher in the control. The water-holding capacity, myofibrillar protein and shear force were significantly higher in T3 than other surimi samples. All gel characteristics were significantly higher in the control and T3 than other surimi samples. pH 11.0 adjusted chicken breast surimi had greater lightness than the control, and T3 samples had the highest lightness and whiteness. Sensory evaluations were significantly higher in the control and T3 than the other samples. The gel, and physical characteristics and sensory evaluation of T3 were similar to the control. T3 samples had superior color and pH than the control Alaska pollack surimi.

• 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.

• Journal of Korean Society of Environmental Engineers
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• v.22 no.4
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• pp.765-773
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• 2000

The degradation of humic acid using $TiO_2$ coatings was studied, $TiO_2$ coatings were prepared by dip-coating method. Sol solutions for coating were prepared by mixing the gel, which can be produced by the reaction of $TiOCl_2$ and $NH_4OH$ solution, and hydrogen peroxide solution, and hydrolysis of titanium tetraisopropoxide (TTIP). It was shown from XRD that coatings from sol aged at $100^{\circ}C$ for 18h with titanium peroxo solution were crystallized to anatase in the range of temperatures of $25^{\circ}C$ to $500^{\circ}C$. In contrast, those coated from TTIP were crystallized to anatase at temperature above $400^{\circ}C$. So the sols originated from $TiCl_4$ can be applied for not only on the heat-resistance substrates but on the plastic substrates. Thickness and the quality of the films were dependent on the withdrawing speed, the concentration of sol, and the number of coating. The films showed various interference colors depending on the thickness of them. In the case that the films coated 2 times at withdrawing speed of 2.5cm per minute by 0.2M sol, the films had a transparent light blue color with thickness of around 50nm. It was known from the result of photo-degradation by $TiO_2$ coatings using humic acid that the removal efficiency of $COD_{cr}$ was over 85% after illumination of $UV/H_2O_2$ for 40min. and that of UV/VIS absorbable materials was over 95%.

• Journal of the Mineralogical Society of Korea
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• v.20 no.4
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• pp.277-287
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• 2007

To understand the effects of the powdered manganese nodule and sea bottom sediment pumped up with nodules on the mining process, the shattering ratio of manganese nodule and their physical properties are analyzed. The self shattering ratio and crushing shattering ratio are about 27% and about 3%, respectively. Then total shattering ratio is about 30%. The initial turbidity of the powdered manganese nodule and the bottom sediment show high, i.e., about 3,100 and 1,850 respectively. But their turbidities decrease rapidly with time. After 1 hour, turbidity of the powdered manganese nodule drops to about 1,570 and that of the bottom sediment to 1,310. The turbidity of Na-bentonite changes from 820 to 730 after 1 h and to 700 after 2 h. The viscosity of powdered manganese nodule is $1.4{\sim}1.5cP$, and the viscosity of bottom sediment is less than 1 cP. The viscosity fo Na-bentonite is initially 37.2 and increase with time to 86.4 cP after 30 min. The high initial turbidity of powdered manganese nodule is due to dark color of the powder. The high specific gravity makes rapid precipitation and then decreases the turbidity rapidly. The bottom sediment shows high initial turbidity because of easy suspension with very fine particle size. But it cannot be hydrated and formed gel in suspension, then it is easily precipitated. However Na-bentonite is hydrated to the expended state and makes gel state, then it shows high turbidity and high viscosity. These physical properties of the powdered manganese nodule suggest that the powder of manganese nodule should not make scaling inside of lifting pipe or pump. And the bottom sediment lifted up with manganese nodule should not play the role of drilling mud shch as Na-bentonite.

• Journal of Veterinary Clinics
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• v.8 no.2
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• pp.127-142
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• 1991

This study was carried out to investigate fatty liver in Korean black goats. Adult female goats were divided into 3 test groups(A, B and C). Group A and B of goats each received 3 test consecutive daily doses of DL-ethionine at 75mg/kg and 150mg/kg body weight, respectively. Group C of goats was given 3 consecutive doses of the compound every 48 hours at 150mg/kg body weight. The clinical symptoms, hematological values, serum chemical values and histopathological study of the liver were investigated in the test animals. The results obtained are as follows ; 1. Fatty liver were observed in every test animal. 2. Some clinical symptoms( anorexia, depression) were appeared from 1st day to 7th day after administration of the compound in every test animal. In addition to these symptoms, diarrhea and salivation were generally observed in test animals which were given the compound at 150mg/kg body weight. The degree of these symptoms was dose dependent. 3. There was no significant variations in total WBC counts and fibrinogen values in the blood of test goats. The PCV values were significantly increased on 5th day of dosing in group A and B of goats. 4. The total lipid value was not changed but the concentration of NEFA was significantly increased on 3rd day of dosing with the compound and returned to normal value after 10 days hereafter. The value of triglycerides was significantly increased on 1st day and returned to normal value on 3rd day of dosing. The value of cholesterol was significantly decreased on 3rd day and returned to normal value on 10th day after treatment. 5. Total protein level was decreased on 10th day of dosing in the groups of B and C, and billirubin level was significantly increased on 7th day of dosing in every test group and returned to normal level after 13th day of administration. 6. The activity of GGT in serum was not changed while the activities of SDH and AST were significantly increased in every test goat and those values were returned to normal after 10~13th day of trestment. 7 The 35K-protein fraction in serum was not detected by SDS-polyacrylamide gel electrophoresis, but this protein fraction was detected by the same method after treating the 21st and 22nd fraction which were obtained by column chromatography with Sephadex G-100. 8. The affected liver was congested and swollen on 3rd day, and yellowish brown in color and mottled appearance on 7th day of treatment. Histopathologically, fat droplets were common in the hepatocytes, this change was intensive on 7th day after treatment in group B and C. Hepatic cell necrosis was observed in some livers but this pathological change was disappeared and returned to normal after 13 days of treatment.

• Journal of Korean Society of Environmental Engineers
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• v.29 no.12
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• pp.1371-1380
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• 2007

Study on the instability of waste plastic's thermal pyrolysis oil was carried out for the purpose of improving its quality. The reaction of pyrolysis oil with ozone changed double bonds into aldehydes and ketone, estimated that HDPE pyrolysis oil contained $\sim45$ wt% 1-alkene type olefins, and PP pyrolysis oil did $\sim73$ wt% olefins, which consisted of $\sim47$ wt% secondary and $\sim20$ wt% primary alkenes. The dark brown color and odor of pyrolysis oil were improved by eliminating double bonds, indicated that they were directly related to unsaturated hydrocarbons. Container test showed that metal can affected oil quality worse than the brown glass bottle. Antioxidant added into pyrolysis oil was consumed up to 90% within $2\sim3$ days and the wt. composition of unsaturated hydrocarbons in pyrolysis oil was not changed within 50 days, inferring that instability of pyrolysis oil due to unsaturated bonds can be stabilized by antioxidants. Adsorption test on silica gel, activated carbon and alumina to remove precipitates in oil produced a good result, but not enough to remove moisture. However, cheap anhydrous sodium carbonate showed the best removal efficiency of moisture as well as precipitates in oil. Therefore the pyrolysis oil quality improvement was accomplished by applying anhydrous $Na_2CO_3$ into the production plant.

• Korean Journal of Food Science and Technology
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• v.38 no.3
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• pp.419-426
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• 2006

A thermophilic microorganism, strain JE 375, which produces a thermostable protease, was isolated from soil and compost in Korea. This gram-positive, rod-shaped, catalase positive, motility positive, and hemolysis ${\beta}$ containing organism was implicated in glucose fermentation, mannitol fermentation, xylose oxidation, aerobic activity and spore formation. The color of the colony was yellowish white. The temperature range for growth at pH 6.5 was between 55 and $70^{\circ}C$, with an optimum growth temperature of $65^{\circ}C$. This result confirmed the strain JE 375 as a thermophilic microorganism. The enzyme was produced aerobically at $65^{\circ}C$ during 20 hr in a medium (pH 6.5) containing 1% trypton. 1% maltose, 0.5% yeast extract and 1% NaCl. The 16S rDNA of strain JE 375 had 97.6% sequence similarity with the 16S rDNA of Bacillus caldoxyloyticus. On the basis of biochemical and physiological properties and phylogenetic analysis, we named the isolated strain as Bacillus sp. JE 375. The thermostable protease from Bacillus sp. JE 375 had been partially purified and characterized. The molecular weight of the enzyme was deduced from SDS-PAGE and gel chromatography as 55 kDa and its optimal temperature was $60^{\circ}C$. The enzyme showed its highest activity at pH 7.5 and was stable from pH 7.0 to 8.0.

• Korean journal of food and cookery science
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• v.21 no.1 s.85
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• pp.117-123
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• 2005

Washed rice was coated by spraying aqueous dandelion (Taraxacum officinale) extracts at 20, 30, 40 $^{\circ}$Brix and dried at room temperature. The coating procedure was conducted 5 mL/min for 10min. Property changes in the dandelion coated rice and un-coated cooked rice were observed during 2 days of storage. Increasing the coating concentration was associated with lower color values (L, a value) and moisture contents. Sensory and texture properties generally decreased in the cooked rice coated with dandelion more than the control (non-coated rice). But, D-20(20 $^{\circ}$Brix of the dandelion concentration) resulted in better textural properties and sensory scores for hardness and overall acceptability in cooked rice. Compared to the control, the washed rice coated with 20 $^{\circ}$Brix for 0 and 2 days showed better quality in sensory activities, a lower gel consistency and better textural activities. It was concluded that the optimum coating ration of rice and added dandelion extract for cooking were 20 $^{\circ}$Brix and $5\%$ respectively, in proportion to the total weight of raw rice.

• Journal of the East Asian Society of Dietary Life
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• v.19 no.4
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• pp.627-634
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• 2009

In this study, the physicochemical and sensory characteristics of jellies prepared with various types and amounts of garlic were investigated; jellies with dried garlic powder (0.5%, 1%, 1.5%, 2%), jellies with $50^{\circ}$ brix fresh garlic extract (0.5%, 1%, 1.5%, 2%), jellies with $15^{\circ}$ brix black garlic extract (5%, 10%, 15%, 20%). The total polyphenols, flavonoids and crude protein contents of the black garlic extract were similar to those of the fresh garlic extract. The ability of the black garlic extract to scavenge 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2'-azinobis (3-ethylbenzthiazoline-6 -sulfonate) (ABTS) radicals were significantly (p<0.01) higher than those of the fresh garlic extract. The Hunter b values decreased as the amount of added garlic increased. In addition, the hardness and gel strength of texture also decreased as the amount of added garlic increased. The flavor preference of jellies prepared with the dried garlic powder (1% and 1.5%) was significantly lower compared to normal jelly (p<0.05). Jelly prepared with 20% black garlic extract showed the highest texture preference of all the tested jellies (p<0.05). There were no significant differences in color, taste and overall preference between normal jelly and garlic jellies.