• 분석과학
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• 제8권4호
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• pp.575-582
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• 1995

A new analytical procedure using a serial dual electrode detector was developed for the analysis of amino acids and proteins. Bromine was generated at the upstream electrode and detected by the downstream electrode. The presence of amino acids and proteins was shown to lower the downstream current but with no apparent effect on the upstream current. This indirect mode of detection can be applied to the determination of amino acids and proteins which are electrochemically inactive or too large to be accessible to the electrode surface for electron exchange. The method is shown capable to determine various amino acids (cystine, tyrosine, lysine, tryptophan, glycine, methionine and arginine) and proteins (cytochrome c, hemoglobin, HAS, a-Amylase, Conalbumin I, Catalase and Myglobin) with linear working range for amino acids between $10^{-6}$ to $10^{-3}M$ and total proteins between $10^{-7}$ to $10^{-3}M$. The method has been applied for the analysis of amino acids and total protein in food using Flow Injection Analysis with results obtained comparable to those using the traditional analytical procedure. Use of pulse generation technique was shown to produce a more stable flow injection analysis peaks for repetitive determination than the use of conventional constant current method which showed increase of the background current after determination over 200 minutes. The pulse method was found to give stable baseline even after 400 minutes. Thus, the method is shown able to provide a suitable analytical procedure for automatic analysis of amino acids and proteins in food by flow injection analysis.

• 생약학회지
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• 제13권1호
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• pp.43-46
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• 1982

Free amino acids and total amino acids were detected by two dimensional TLC method in some edible mushrooms in Korea. The result is presented in the Table I and the chromatograms are shown in the Fig. 1 to 6.

• Preventive Nutrition and Food Science
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• 제14권4호
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• pp.316-322
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• 2009

This study was performed to quantitatively analyze free amino acids in the bean sprouts of three different merchants by the parts and the cooking methods in order to evaluate the nutritional and sensory values of bean sprouts. Three merchant bean sprouts were analyzed from total, cotyledon and hypocotyls. Aspartic acid was the most common acid isolated from bean sprouts from all three merchants and was found more in the hypocotyls than the cotyledon. On the other hand, arginine, the second most common amino acid, was found more in the cotyledon than the hypocotyls while valine, the third or fourth most common amino acid in total bean sprout, occurred in a greater amount in hypocotyls than in cotyledons. After cooking, was the most concentrated amino acid in the liquid portion of both boiled bean sprouts and bean sprout soup was glutamic acid. Total bean sprouts from merchant C showed significantly higher contents of the most abundant amino acids, such as aspartic acid, arginine, alanine, serine, glutamic acid, isoleucine, leucine and tyrosine (p<0.05). After cooking, bean sprouts from merchant B showed less of a decrease in amino acid content in the solid parts than the products from merchants A and C. In conclusion, aspartic acid was the major amino acid in bean sprouts, regardless of the source, but after cooking, glutamic acid became the most abundant amino acid in the liquid part. Additionally, the pattern of release of the amino acids from the solid beans to the liquid portion during cooking was different with each merchant.

• Fisheries and Aquatic Sciences
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• 제8권2호
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• pp.43-50
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• 2005

We evaluated the nutritional composition of the siphon of the surf clam Tresus keenae in regard to the presence of nitrogenous [amino acids, nucleotides and their related compounds, total creatinine, betaine, trimethylamine oxide (TMAO), and trimethylamine (TMA)] and non­nitrogenous compounds (sugars and organic acids), lipid fatty-acid composition, and occurrence of minerals. The content of total free amino acids was 660.27 $\pm$ 7.94 mg/100 g, and the predominant amino acids were arginine, alanine, sarcosine, glycine, and glutamic acid. These amino acids accounted for $71\;\%$ of the total free amino acids. Among the nucleotides and their related compounds, inosine was the major component and comprised 40.38 $\pm$ 0.02 mg/100 g. Free amino acids were the largest contributor to total extracted nitrogen, comprising $49.94\%$, followed by total creatinine, betaine, nucleotides, and ammonia; the contribution of TMAO and TMA was small. For the non-nitrogenous compounds, malic acid, propionic acid, and succinic acid comprised the major portion of the ten kinds of organic acids detected, and the sugars found were glucose, maltose, and arabinose, which were estimated to be $147.0\pm7.15,\;34.45\pm1.09,\;and\;1.21\pm0.02\;mg/100\;g,$ respectively. The predominant minerals were Na and K, which comprised $11.43\pm1.06\;and\;9.46\pm1.02\;mg/100\;g,$ respectively. The major fatty acids were C22:6, C20:5, C23:0, C18:3, and C16:0 in the lipid fractions. The 23:0 level of glycolipid (GL) was the highest of any other lipid fraction. The amount of total polyunsaturated fatty acids (PUFA) in the lipid fractions was higher, ranging from $58.22\%\;in\;GL\;to\;77.1\%$ in phospholipid (PL), compared to the saturated and monounsaturated fatty acids. Of the n-3 fatty acids, C20:5 and C22:6 contributed $35.30-64.44\%$ of PUFA in the lipid fractions. The ratios of n-3 to n-6 PUFA in total lipid (TL), neutral lipid (NL), PL, and GL were 4.35, 4.26, 6.69, and 2.04, respectively.

• 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%.

• Journal of Nutrition and Health
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• 제10권4호
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• pp.97-103
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• 1977

Changes of free amino acids as taste compounds during the fermentation of oyster were analyzed by amino acid autoanalyzer. In fresh oyster, taurine, glutamic acid and alanine were abundant amino acids and the amounts of taurine (731mg%, on moisture and salt free base), glutamic acid (365mg%) and alanine (345.4mg% ) were 63.8% of the total free amino acids. Cystine, isoleucine, phenylalanine, leucine and histidine were detected as less abundant free amino acids and the amount of those amino. acids ranged from 5. 5mg% (cystine) to 32.9mg% (histidine). The free amino acids analyzed in this experiment were not changed in composition hut changed in amounts during 124 days of fermentation. Aspartic acid and leucine were continually increased during 124 days of fermentation. Lysine, histidine, threonine, serine, glutamic acid, tyrosine and phenyalanine were increased unlit 68 days of fermentation and than decreased gradually. The increase of arginine, glycine, valine and isoleucine were fluctuated. Taurine were dramatically decreased during the 124 days of fermentation. It is believed that glutamic acid, alanine, lecuine, serine, Iysine and threonine play an important role as taste compounds in fermented oyster because those amino acids were most abundant in fermented oyster.

• 한국수산과학회지
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• 제11권2호
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• pp.65-83
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• 1978

This study was attempted to evaluate the taste of broiled-dried sea mussel which is a traditional dried Sea food in Korea. The contents of such compounds as free amino acids, nucleotides and their related compounds, TMAO, betaine, and nonvolatile organic acids were analysed. From the results of analysis of nucleotides, the contents of AMP and ADP in broiled-dried Mytilus coruscus and Mytilus edulis appeared higher than other nucleotides and tended to increase slightly after cooking, drying, and storage which might be due to both their stability and the addition of degradation of nucleic acids during cooking. In the free amino acid composition of fresh samples abundant amino were taurine, glycine, serine, glutamic acid, alanine, arginine, threonine, tyrosine, lysine and valine in order. Such amino acids as histidine, leucine, methionine and isoleucine were poor and both proline and phenylalanine were merely trace. The free amino acid composition in the extract of Mytilus corucus and Mytilus edulis after broil-drying was not changed. These amino acids, taurine, glycine, feline, glutamic acid, alanine and arginine were abundant in dried samples as well as in the fresh. The total free amino acid was greatly reduced after cooking and drying ranging from $76.3\%$ to $79.7\%$ loss to that of tile fresh. The content of betaine shelved the same tendency as in total free amino acid while TMA slightly increased relating to TMAO decrease during broil-frying. Such nonvolatile organic acids as succinic, lactic, malic and fumaric acid were abundant in both fresh and broiled-dried samples whereas oxalic and pyruvic acid were poor. It is found that the taste compounds of broiled-dried Mytilus coruscus and Mytilus edulis were composed of amino acids as glycine, serine, alanine, glutamic acid, arginine, and betaine, TMAO, ADP, AMP, and organic acids such as succinic acid, lactic acid, malic acid and fumaric acid. No significant differences in the taste compounds between male and female as well as between Mytilus coruscus and Mytilus edulis was not observed.

• Bulletin of the Korean Chemical Society
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• 제24권12호
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• pp.1757-1762
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• 2003

The interrelation between retention factors of several L-amino acids and their physico-chemical and structural properties can be determined in chromatographic research. In this paper we describe a predictor for retention factors with various properties of the L-amino acids. Eighteen L-amino acids are included in this study, and retention factors are measured experimentally by RP-HPLC. Binding energy ($E_b$), hydrophobicity (log P), molecular refractivity (MR), polarizability (${\alpha}$), total energy ($E_t$), water solubility (log S), connectivity index (${\chi}$) of different orders and Wiener index (w) are theoretically calculated. Relationships between these properties and retention factors are established, and their predictive and interpretive ability are evaluated. The equation of the relationship between retention factors and various descriptors of L-amino acids is suggested as linear and multiple linear form, and the correlation coefficients estimated are relatively higher than 0.90.

• KSBB Journal
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• 제7권3호
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• pp.186-190
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• 1992

송충이의 유리 아미노산, 총 아미노산 조성과 총 지방산 조성을 규명하기 위해 Gas chromarography와 HPLC를 사용하여 분리 정량한 결과는 다음과 같다. 조지방 함량은 21.00%이고, 조단백질 함량은 58.47%로 조성되어 있다. 유리 아미노산의 총 함량은 3.65g/100g으로 조성되어 있으며, 유리 아미노산 중에서 필수 아미노산의 총 함량은 1.31g/100g으로 35.89%를 차지하고 있다. 총 아미노산의 총 함량은 41.20g/100g으로 조성되어 있으며 총 아미노산 중에서 필수 아미노산의 총 함량은 14.75g/100g으로 35.80%를 차지하고 있다. 총 지방산 조성은 $C_{18}$=26.81%로 제일 많이 함유되어 있고, $C_{16}$=19.09%, $C_{18:1}$=18.74%, $C_{18:3}$=15.33%, $C_{16:1}$=7.29%, $C_{20}$=5.21%순으로 함유되어 있으며, 불포화 지방산이 45.88%이고, 필수 지방산은 19.73%를 차지하고 있다.

• 대한가정학회지
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• 제24권4호
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• pp.105-116
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• 1986

This paper provides the analysis and the comparisons of three kinds of soy sauces based on the manufacturing sources. The main factors of this study are concentrated on general and amino acids components. Three samples represented as domestic market soy sauces, imported Japanese soy sauces and homemade soy sauce are analyzed and compared by Kjeldahl and AOAC method and amino acid autoanlyzer method which have the results as follows; 1. For total nitrogen and pure extract and sodium chloride known as general components, the domestic market soy sauces show the ranges of 0.85~1.51%, 11.37~17.4% and 16.03~17.43% and the imported soy sauce shows the ranges of 1.65~1.83%, 19.54~19.80%, 17.20~18.46% and the homemade soy sauce indicates 0.73%, 30.96% for each components. The results implicates that the homemade soy sauce contains less total nitrogen and pure extract while it contains more sodium chloride than the domestic market soy sauces. 2. The amount of total amino acids contained in each soy indicated the range of 3.864~6.883% for the domestic market soy sauce and the range of 7.705~7.839% for the imported soy sauce and 2.035% for the homemade soy sauce. Especially, 20~50% glutamic acids are contained in total amino acids of each soy sauces.