• KSBB Journal
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• v.18 no.6
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• pp.495-499
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• 2003

The effect of operating parameters (reaction temperature and time) and reaction modes (batch and semi-batch) on the behavior of amino acid production from hydrothermal decomposition of fish-derived wastes was investigated. The amino acids obtained in batch experiments at temperature of 250$^{\circ}C$ were mainly alanine (Ala) and glycine (Gly) at maximum yield of 65 and 28mg/g-dry fish, respectively. At relatively lower temperature of 200$^{\circ}C$, the yield of high-molecular-weight amino acids such as aspartic acid (Asp) and serine (Ser) is high, but decreases as temperature increases. It is likely that high-molecular-weight amino acids decompose faster than low-molecular ones. Semi-batch mode of reaction suppressed decomposition of amino acids into organic acids (or volatile materials) by continuously removing the products from the reaction zone as soon as they are formed. Thus, large amount of high-molecular-weight amino acids such as Asp and Ser at this reaction mode was observed.

• Korean Journal Plant Pathology
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• v.3 no.1
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• pp.3-7
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• 1987

Ethanol-soluble amino acids and phenolics in healthy and blast-infected leaves of the susceptible rice cultivar Nakdong and adult-plant-resistant cultivar Dobong were quantitatively analyzed, At the 3 days after inoculation, the levels of soluble amino acids and phenolics in the infected fifth and eighth leaves of the two cultivars ere similar to those of comparable healthy controls. As blast lesions appeared on the leaves at the 5 days after inoculation, the soluble amino acids and phenolics began to increase. At the 7 days after inoculation, the levels of amino acids and phenolics were about 1.5-3 times more than those in healthy controls at the five-and eight leaf stages. The adult-plant-resistant cultivar Dobong showed higher amounts of soluble amino acids and phenolics in both healthy and infected fifth and eighth leaves than did the susceptible cultivar Nakdong, although Dobong was less infected by Pyricularia oryzae than Nakdong, The pronounced increases in amino acids and phenolics in rice leaves of the cultivar Dobong during the blast infection may play an important role in the expression of adult-plant resistance to blast.

• Korean Journal of Medicinal Crop Science
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• v.23 no.6
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• pp.454-459
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• 2015

Background : The major compounds of Angelica species are decursin, decursinol angelate, nodakenin, umbelliferone and ${\beta}$-sitosterol, which act anti-inflammatories, reduce pains, protect the liver and enhance the immune system. This study investigated the chemical compositions, minerals, metals, sugars and overall amino acid composition in Angelica gigas Nakai. Methods and Results : Powder of Angelica roots smaller than 30 mesh were used. Physico-chemical analysis revealed the presence of carbohydrates (62.0%), crude proteins (13.9%), moisture (11.4%), crude fats (7.3%) and ash (5.4%). Results showed that potassium was present in the highest amount (1,859 ppm), followed by magnesium (214.5 ppm), calcium (147.3 ppm) and sodium (6.0 ppm). Free sugar profiles showed the presence of sucrose (29.3 g/100 g). The total amino acids concentrations was 9,752 mg/100 g, the most common and dominant amino acids were arginine (2,181 mg/100 g), glutamic acid (1,212 mg/100 g) and aspartic acid (834 mg/100 g). The total free amino acids contents was 1,476 mg/100 g, in which the most common amino acid were arginine (932 mg/100 g), glutamic acid (127 mg/100 g), and ${\gamma}$-aminobutyric acid (80.4 mg/100 g). The fatty acid composition of A. gigas showed a higher concentration of unsaturated fatty acids such as linoleic acid (443.9 mg/100 g) and palmitic acid (181.3 mg/100 g) according to gas chromatography. Conclusions : These results showed that Angelica roots can be used in various fields of foods and medicines, and in the preparation of cosmetics.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.5
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• pp.681-686
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• 2005

The purpose of this study was to analyze the chemical component of Camellia japonica L. according to picking time. Leaves of Camellia japonica L. were picked in April and May,2003. Free sugars (fructose, glucose and sucrose) and organic acids (citric acid, tartaric acid, succinic acid, acetic acid) were present in the Camellia japonica L. leaf. The contents of total free sugars and organic acids increased as picking time was delayed. The major components of free amino acids were aspartic acid, glutamic acid and histidine, and those of total amino acids were histidine and alanine. The contents of total free amino acids and total amino acids were decreased as picking time was delayed, while the ratio of essential amino acids to the total amino acids increased. The amount of minerals (P, Ca, K, Na and Fe), chlorophyll and total polyphenol increased as picking time was delayed.

• Asian-Australasian Journal of Animal Sciences
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• v.15 no.10
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• pp.1507-1516
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• 2002

Meat and bone meal is a valuable protein and mineral source in diets of production animals and contributes to the protein, energy and mineral component of diets. The aim of the present study was to more accurately characterise the apparent ileal amino acid digestibility of meat and bone meals produced in New Zealand and evaluate routine in vitro assays used in practise to measure meat and bone meal quality. A total of 94 commercial meat and bone meals from 25 New Zealand rendering plants over a two and a half year period were analysed for proximates, gross energy, gross amino acid content (incl. hydroxyproline, hydroxylysine and lanthionine), apparent ileal amino acid digestibility, pepsin nitrogen digestibility, protein solubility and bone content. The mean crude protein content of the 94 meat and bone meal samples was 56.8% with a range of >35% units and a coefficient of variation of 9.8%. The mean crude fat and ash content were 10.0 and 28.4% respectively. These latter components showed a large range (16 and 43%, respectively) with coefficients of variation above 22%. Amino acid digestibility between samples was highly variable with lysine and sulphur amino acids digestibility ranging between 45.8-89.0 and 38.2-85.5%, respectively. Pearson correlation coefficients are presented between crude protein content and individual gross amino acids, crude protein content and individual digestible amino acid content, and pepsin N digestibility and individual digestible amino acid content. There was a significant relationship between the digestible amino acid nitrogen content and the crude protein content while pepsin nitrogen digestibility was not correlated to ileal amino acid nitrogen digestibility (r=-0.06). Meat meals with a high protein content had relatively low hydroxyproline and hydroxylysine levels something that was attributed to the levels of collagen from bone. The data indicated that lanthionine (formed upon heat treatment of cysteine with a hydroprotein) is not a good indicator of the heat treatment employed to meat and bone meals. Step-wise multiple regression equations to predict the apparent digestible content of amino acids from rapid in vitro assays are presented. The most selected variables included ash and crude fat content. In general the equations derived for the essential amino acids had a higher degrees of fit (R2) compared to the non-essential amino acids. The R2 for the essential amino acids ranged from 0.43 for histidine and 0.68 for leucine. These equations provide a means of more rapidly estimating the apparent ileal digestible amino acid content (protein quality) of meat and bone meal using standard analyses.

• Journal of the Korean Chemical Society
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• v.36 no.6
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• pp.879-888
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• 1992

Separation of the optical isomers of free amino acids by a reversed phase high performance liquid chromatography has been studied by adding a copper(II) complex of L-proline or L-proline derivatives (hydroxy-L-proline, N-benzyl-L-proline, p-xylenyl-L-proline, p-xylenyl-hydroxy-L-proline) in the mobile phase. An OPA postcolumn detection system was used for the detection of amino acids. The chromatographic properties for the free amino acids were discussed in terms of the pH, the kinds and concentration of chelate or organic modifier. The retention behaviors of the free amino acids were considerably different from, those of DNS-amino acids or DABS-amino acids. The enantioselectivity of the free amino acids was better than that of derivatized amino acids. The enantioselectivity between the optical isomers observed by use of the Cu(II)-p-xylenyl-L-proline chiral cheleate was the best among the several copper(II) chelate. A separation mechanism could be illustrated not only by the hydrophobic interaction of the diastereomer with stationary phase but also by the steric effect of the ligand exchange reaction between the free-amino acids and copper chelate.

• Bulletin of the Korean Chemical Society
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• v.31 no.5
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• pp.1289-1294
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• 2010

Novel $H_8$-binaphthol-based chiral receptors appended with an uryl moiety (2a) and a guanidinium moiety (2b) have been designed and synthesized for the enantioselective recognition of 1,2-amino alcohols via reversible imine formation. The selectivities ($K_R/K_S$ = 9.8 ~ 19.4) of 2b in imine formation with 1,2-amino alcohols are higher than those of 2a ($K_R/K_S$ = 1.8 ~ 4.5). Similar efficiency trend have been observed in the conversion of L-amino acids to D-amino acids, i.e., the efficiency of the receptor 2b (D/L ratio: 4.3 ~ 10.1) is superior to 2a (D/L ratio: 4.0 ~ 8.7).

• Journal of Nutrition and Health
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• v.37 no.2
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• pp.108-114
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• 2004

This study was performed to determine the effect of dietary Na levels on plasma amino acid levels. Plasma amino acid levels were compared in 20 adult healthy women subjects who were given high Na diet (290.48 mEq/day : NaCl 17g) or low Na diet (51.26 mEq/day : NaCl 3g) for subsequent 6 days. Plasma essential amino acids levels were significantly decreased (36%) while plasma non-essential amino acids levels were significantly increased (22%) when subjects were given low Na diet (p＜0.001). Among essential amino acids, threonine was decreased (74%) significantly when subjects were given low Na diet (p＜0.01). Among nonessential amino acids, serine (49%), proline (20%) and aspartic acid (14%) were increased (p＜0.01), while arginine (48%) and glutamic acid (27%) were decreased (p＜0.001). In conclusion, dietary Na contents seemed to be an important factor to affect plasma amino acid levels. It would be appropriate to decrease the dietary Na intakes level considering the various clinical effects of dietary Na on the body fluid. For the patients who need low Na diet, it would be suggested that the level of dietary proteins should be carefully considered along with dietary Na manipulation. (Korean J Nutrition 37(2) : 108-114, 2004)

• Food Science of Animal Resources
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• v.32 no.3
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• pp.369-375
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• 2012

The current study was carried out to investigate the impact of extraction conditions on the free amino acid level and type in beef longissimus muscle. The sample blocks were chiller aged for 1 d and 7 d at $4^{\circ}C$. There are three homogenization speeds (11,000, 19,000 and 24,000 rpm) for bigger and two speeds (11,000 and 13,000 rpm) for smaller homogenizer's dispersing tools were used for evaluation. Results showed that chiller ageing greatly (p<0.05) increased extractable free amino acids, except cystine. Homogenization with the bigger dispersing tool at 24,000 rpm resulted in the highest free amino acid levels for both 1 and 7 d samples. Significant differences (p<0.05) in the mean values of most amino acids due to the effect of speed and interactions between ageing times. However, the speed effect and interaction between ageing with homogenization speed were not significant (p>0.05) for most of the amino acids except valine and isoleucine when using the smaller dispensing tools. The current data indicated that a standardized method for free amino acid types and levels of aged beef samples. In addition, the results also suggested that utilization of a big dispensing tool at high homogenization speed is a better condition for releasing free amino acid contents in beef samples.

• Preventive Nutrition and Food Science
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• v.14 no.4
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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.