• 대한가정학회지
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• 제20권4호
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• pp.99-105
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• 1982

Changes of free amino acids as taste compunds during the fermentation of cod-roe, Gadus marcrocephlus, were analyzed by a amino acid autoanalyzer. Leucine, lysine, valine, isoleucine and arginine were dominent amino acids in fresh cod-roe extracts, and the amounts of leucine (797.3mg%, on moisture and salt free base), lysine (577.7mg%) and valine(487.4mg%0 were 54.9% of total free amino acids. The contents of methionine, histidine, tyrosine and phenylanine were lower, and aspartic acid, glycine, threonine, glutamic acid and serine were detected trace amount. The free amino acids analyzed in this experiment were not changed in composition but changed in the amounts during 80 days of the fermentation. Total free amino acids were increased until 59 days of fermentation and than decreased gradually.

• 대한가정학회지
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• 제25권4호
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• pp.47-55
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• 1987

This study was designed to elucidate the lipid contents, neutral lipids components and fatty acid composition in fresh shellfishes, produced in Korea. Four kinds of shellfishes including sea mussel, short-necked clam, corb shell and and ark shell were selected according to the higher sales order and cheaper retail price at fish markets in Seoul in July 1985. The results abtained were as follows; 1. The average total lipid contents in four shellfishes were 2.3% by wet weight basis. The ratios of neutrial lipid, glycolipid and phospholipid in the total lipid were 51.1 : 4.9 : 44.0 in sea mussel, 66.0 : 3.2 : 30.8 in ark shell, 37.8 : 2.2 : 60.0 in short-necked clam and 54.5 : 2.0 : 53.5 in corb shell, 2. The average value of acid value, iodine value and unsaponifiables contents of total lipids were 1.3, 217.8, 92.0 and 20.3%, respectively. 3. The composition of the neutral lipids were triglycerides, esterified fatty acids, sterylesters, free sterols and monoglycerides in four shellfishes. 4. The major fatty acid composition of total lipids were palmitic, eicosapentaenoic, docosahexaenoic and palmitoleic acids in four shellfishes. The average total unsaturated fatty acids of total lipid were 64.5%, and $\omega$-3 highly unsaturated fatty acids were 27.0%. The average p/s Ratiio were 1.3.

• EDISON SW 활용 경진대회 논문집
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• 제3회(2014년)
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• pp.103-113
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• 2014

Hydrophobicity is the key concept to understand the role of water in protein folding, protein self-assembly, and protein-ligand interaction. Conventionally, hydrophobicity of amino acids in a protein has been argued based on hydrophobicity scales determined for individual free amino acids, assuming that those scales are unaltered when amino acids are embedded in a protein. Here, we investigate how the hydrophobicity of constituent amino acids depends on the protein context, in particular, on the total charge and secondary structures of a protein. To this end, we compute and analyze the hydration free energy - free energy change upon hydration quantifying the hydrophobicity - of three short proteins based on the integral-equation theory of liquids. We find that the hydration free energy of charged amino acids is significantly affected by the protein total charge and exhibits contrasting behavior depending on the protein net charge being positive or negative. We also observe that amino acids in the central ${\beta}$-strand sandwiched by ${\beta}$-sheets display more enhanced hydrophobicity than free amino acids, whereas those in the ${\alpha}$-helix do not clearly show such a tendency. Our results provide novel insights into the hydrophobicity of amino acids, and will be valuable for rationalizing and predicting the strength of water-mediated interaction involved in the biological activity of proteins.

• 한국연초학회지
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• 제7권1호
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• pp.85-92
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• 1985

Extraction efficienties of volatile organic acids in tobacco leaves according to several extraction methods were investigated and contents of volatile organic acids in 16 kinds of tobacco leaf varieties were compared. Extraction efficiency according to simultaneous distillation and extraction was 5 to 10 times higher than that according to solvent extraction, steam distillation, essential oil extraction or continuous extraction and distillation. Total contents of volatile organic acids were 1.62 to 12.94mg per l00g of sample in aromatic tobacco varieties,0.12 to 2.08mg in flue-cured tobacco leaves, and trace in burleys. Among the Korean aromatic tobacco varieties, total contents of volatile organic acids in ST374-3 were the highest, 4.66mg per l00g of sample, and those in Sohyang and Hyangcho were low, 1.69mg and 1.62mg, respectively. Among flue-cured tobacco varieties, those in NC2326 were the highest, 2.08mg per 100g of sample, but those in the other varieties were not more than 0.80mg per 1 00g of sample. Total contents of volatile organic acids in acidic hydrolysis with 0.1 M tartaric acid were higher than in non-acidic condition in all kinds of tobacco varieties.

• Journal of Nutrition and Health
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• 제33권1호
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• pp.13-22
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• 2000

Effects of high fat diet and/or endurance exercise training on hepatic total and phospholipid(PL) fatty acid compositions were evaluated in rats fed one of the following diets for 31 days. control diet(CD, 5 wt% corn oil) or high fat diet(HFD, 35 wt% corn oil). Half of the rats in each group were exercise-trained regularly on a treadmill for 90 minutes/day during the entire feeding period. Total and PL fatty acid compositions of hepatic lipid extracts were determined by a gas-liquid chromatograph),. Endurance exercise training did not change the daily food intake, but significantly reduced body weight gain and feed efficiency ratio of rats, which were most prominent in animals fed HFD. Exercise training did not significantly change the percentages of ∑saturated fatty acids (SFA) and ∑polyunsaturated fatty acids(PUEA), but decreased the percentage of ∑monounsaturated fatty acids(MUFA) in hepatic total fatty acids, which might be associated with the decrease in (equation omitted) 9-desaturation index of hepatic total fatty acid metabolism. Exercise training significantly lowered the percentages of 16 : 0 and 22 : 5$\omega$3, and increased the percentages of 20 : 1 and 20 : 3$\omega$3 in both total and PL fatty acid compositions in rat liver. Both total fatty acid and PL fatty acid compositions of rat liver responded more sensitively to changes in dietary fat content than to endurance exercise training in this study. Feeding HFD, whoch contains high level of linoleic acid(LA, 18 : 2$\omega$6), significantly decreased the percentages of ∑SFA and $\Sigma$MUFA, and increased the percentages of ∑PUFA and ∑$\omega$6 fatty acids of hepatic total fatty acids. Hepatic total fatty acid composition was affected by dietary fat content and dietary fatty acid composition more sensitively than those found in hepatic PL fatty acid composition. HFD significantly decreased most of desaturation indices, while exercise training significantly decreased elongation index(20 : 5$\omega$3⇒22 : 5$\omega$3) of hepatic total and PL fatty acid metabolism in rats. (Korean J Nutrition 33(1) : 13-22, 2000)

• 한국영양학회:학술대회논문집
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• 한국영양학회 1994년도 춘계심포지움 및 발표논문 초록
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• pp.41-41
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• 1994

• 한국식품과학회지
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• 제21권1호
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• pp.58-62
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• 1989

국내에서 널리 인공재배 되고 있는 식용버섯인 양송이 (Agaricus bisporus), 느타리(Pleurotus ostreatus) 및 표고버섯(Lentinus edodes)의 부위별 유리아미노산 및 전아미노산을 아미노산 자동분석기로 비교 검토하였다. 3종의 버섯에서 18종의 아미노산들을 확인 정량하였다. 이들이 함유한 총질소의 함량은 $1.67{\sim)6.42%$이었고 단백태질소는 $0.88{\sim}2.42%$의 범위로 종류 및 부위에 따라 큰 차이를 보였으며 이들 질소화합물들은 자루보다도 갓부위에 더 높게 분포하고 있었다. 유리아미노산의 분포범위는 $10.04{\sim}37.85mg/g(dry\;weight)$, 전아미노산의 범위는 $53.37{\sim}120.15mg/g(dry\;wieht)$로 나타났다. 유리아미노산중 가장 많이 분포하는 아미노산은 glutamic acid였으며 그 다음으로는 serine, histidine, alanine 순이었다. 전아미노산중 가장 많이 분포하는 아미노산은 glutamic acid이었으며, 그 다음으로는 aspartic acid, histidine, alanine순이었다.

• Journal of Pharmaceutical Investigation
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• 제21권2호
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• pp.67-71
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• 1991

A simple and sensitive method was developed for the quantification of free and conjugated bile acids in bezoar without prior hydrolysis. $3{\alpha}-Hydroxy$ bile acids are first oxidized to 3-keto bile acids in the reaction catalyzed by $3{\alpha}-hydroxysteroid$ $dehydrogenase(3{\alpha}-HSD)$. During this oxidative reaction, an equimolar quantity of nicotinamide adenine dinucleotide(NAD) is reduced to NADH and subsequently oxidized to NAD with concomitant reduction of nitrotetrazolium blue(NTB) to diformazan by the catalytic action of diaphorase. The diformazan has an absorbance maximum at 540 nm. The intensity of the color produced is directly proportional to bile acids concentration in the bezoar extracts. The optimum conditions for the enzymatic reaction such as effects of reaction time, reaction temperature and pH, and stability were investigated. Calibration plots for the sodium chelate observed to be linear and intra-, inter-assay analytical recovery of bile acids averaged $97.65{\pm}3.4%(S.D.)$. Therefore, it is considered that the quality control of total bile acids from bezoar or bezoar-containing liquid preparation using this simple and sensitive assay system will be acceptable. Also current bezoars and bezoar-containing liauid preparations were examined their total bile acids from this method.

• 한국식품영양과학회지
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• 제29권2호
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• pp.211-217
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• 2000

To standardize quality characteristics of commercial doenjang prepared by traditional method, general components, organic acids, amino acids and fatty acid composition were investigated. Moisture, crude protein, crude lipid, titratable acidity (expressed as milliliter of 0.1 N NaOH), acid value and salinity were 54.7%, 13.8%, 8.0%, 14.4mL, 45.7mg/g and 11.8%, respectively. The content of amino type nitrogen was 345.3mg% (w/w) in the range of 207.6 to 443.5mg% being 1.1~2.2-fold for all samples. Average value of Hunter color for L(lightness), a(redness) and b(yellowness) were 37.4, ＋9.7 and ＋21.3, respectively. Browning index value(expressed as optical density at 425 nm) of water-soluble compound(2.58) was above 7.1 times higher than that of the water-insoluble compound(0.38). Total contents of free and total amino acid were 3.81 and 9.72%, respectively, and then the former(1.1~3.7 times) was more different in all samples tested than that of the latter(1.1~2.0 times). Among amino acids, glutamic acid was abundant and its content of free and total amino acids was 0.57 and 1.24%, respectively. Of organic acids, lactic acid was the most abundant being 0.34%(average) and ranged from 0.15 to 0.86%. Linoleic acid(52.17%, as area%) was the highest content of the total fatty acids. Unsaturated and polyunsaturated fatty acids were 83.89 and 61.189%, respectively. Polyunsaturated fatty acid was markedly different among all samples and ranged from 51.52 to 64.91%.

• 한국식품영양학회지
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• 제6권2호
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• pp.73-80
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• 1993

In order to examine food components of coho salmon and rainbow-trout, We analyzed the composition of protein, amino acids and total lipids. The coho salmon muscle contained about 19.3% of protein with the composition of 29.9% in sarcoplasmic protein, 56.3oA in myofibrillar protein 12.5% alkali soluble protein and 2.6% in stroma. Those of rainbow-trout contained 34.1%, 56.4%, 8.3% and 2.9%, respectively. The sarcoplasmic and myofibrillar protein were composed of 13 subunits in coho salmon, and 16 and 15 subunits in rainbow-trout. Judging from the contents of essential amino acids, both muscle proteins were complete proteins. The most remarkable feature of free amino acids was that a large amount of dipeptide anserine was present with fairly lower levels of 1 methyl histidine, taurine, histidine, alanine and glycine in both muscle extracts. The total fatty acids of coho salmon was composed of 31.49% polyenes, 43.79% monoenes and 24.73% saturates. The composition of total fatty acid of coho salmon muscle was not different from that of rainbow-trout muscle.