• Journal of the Korean Society of Food Culture
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• v.12 no.2
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• pp.149-153
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• 1997

A variation of free sugar and free amino acid contents of apples during the ripening period was determined by HPLC and amino acid analyzer. The research results are as followes: Fructose, glucose and sucrose were present in the apples. The contents of fructose was the highest, followed by the order of sucrose and glucose. The contents of total sugar in Red fuji was relatively higher than that of Fuji. During the ripening period, the contents of fructose increased conspicuously for the harvesting season and then it decreased gradually. The contents of glucose increased gradually for the harvesting season and then it somewhat decreased. The contents of sucrose increased continually, while, the contents of total free sugar reached the maximum for the harvesting season and then it decreased gradually. A variation in the contents of free amino acid and composition during the ripening period didn't make a significant difference. The major free amino acid of the apples was in the order of aspartic acid, serine, threonine, glutamic acid, histidine, arginine, and alanine. During the ripening period, aspartic acid, threonin, serine, alanine, histidine, and arginine increased gradually. Especially, alanine, histidine, and arginine increased remarkably after the the harvesting season. Glutamic acid, valine, isoleucine, and leucine didn't show much change. The contents of total amino acid increased little by little as the apples ripened, dranstically increased during the harvesting season and slowly increased or slightly decreased after the harvesting seasom.

• Journal of Ginseng Research
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• v.18 no.3
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• pp.204-211
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• 1994

Three unknown ninhydrin positive substances (UK-I, UK-II and UK-III) were detected with an amino acid analyzer in a water extract of Korean red ginseng. One of them (UK-II) was isolated and determined to be maltulosyl arginine (Arg-Fru-Glc) on the basis of chemical and spectroscopic evidence. Another one (VK-III) was identified as Arg-Fru. Maltulosyl arginine, but not Arg-Fru, is a newly identified amino acid derivative. The Korean red ginseng was shown to contain more amount of maltulosyl arginine than the white ginseng. Maltulosyl arginine was found to be produced by the Mallard reaction of maltose with arginine during the heating process involved in preparation of the red ginseng. Maltulosyl arginine was found to inhibit maltase activity. Based on these results, the physiological significance of this new compound is discussed.

• The Korean Journal of Food And Nutrition
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• v.11 no.5
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• pp.499-505
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• 1998

The purpose of this study was to ivestigate the structural characteristics of waste soulble browning reaction prodcuts (WS-BRPs) isolated from Korean red ginseng. They all showed the maximum absorbances at near 280 nm. Their IR spectra suggested the presence of hydroxyl, amide carbonyl and aliphatic methine groups. From sugar analysis it was identified that L and S-1 contained two kinds of suggar, glucose and xylose, and S-2, a fructose together with glucose and xylose. Thirteen different amino acids were identified in L. Ten amino acids from S-1 and seven amino acids from S-2 were identified using Auto Amino Acid Analyzer. Glycine, serine and glutamic acid in S-1 and one unknown amino acid and glycine in S-2 were detected as the major amino acids, respectively. From the 1H-and 13C-NMR spectra, it was identified that a number of sugar moieties, carbonyl and carbon double bonds (only in S-2) were contained in the three WS-BRP components. Approximate number of sugar moiety of L, S-1 and S-2 was determined to be 8∼10, 9∼11 and 4∼5, respectively. Contents of nitrogen, carbon and hydrogen showed L>S-1>S-2.

• Horticultural Science & Technology
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• v.18 no.6
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• pp.808-810
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• 2000

The chemical components of xylem sap collected from kiwifruit (Actinidia chinensis Planch cv. Hayward) trees were analyzed and processing of xylem sap drink were accomplished to increase utilization of xylem sap as a drink. Water content, soluble solids, viscosity, and pH of the xylem sap were 99.60%, 0.90%, 1.01, and 6.50, respectively. In the xylem sap, fructose was the highest among free sugars followed by glucose, sucrose, galactose, and mannitol. The major inorganic components in the sap were calcium, potassium, and magnesium, and calcium was the dominant among them. Ten kinds of amino acids in the xylem sap were detected by amino acid analyzer, and the major amino acids were glutamic acid, lysine, and isoleucine. Glutamic acid was the most dominant amino acid in the xylem sap. Major compositions of xylem sap drink were 74.5% xylem sap, 15% kiwifruit puree and 10% high fructose. Nutritional facts in drink (252 mL) processed by using the xylem sap were 21.8 g sugar, 23.1 mg calcium, 14.1 mg potassium, 554.5 mg amino acid, and 15.6 mg ascorbic acid.

• Korean Journal of Clinical Pharmacy
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• v.8 no.2
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• pp.147-158
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• 1998

The purpose of this study was to test the stability of TPN basic solutions containing amino acids and dextrose. Test solutions containing $4.25\%$ amino acids in $25\%$ dextrose (central TPN basic solution) or $4.25\%$ amino acids in $10\%$ dextrose (peripheral TPN basic solution) were prepared. Two different amino acids solutions $(Fravasol^{(R)}\;vs\;Freamine^{(R)})$ were tested. The samples were taken from each admixture and stored in the evacuated, sterile containers at $2{\sim}8^{\circ}C$ and ambient room temperature. Each sample was analyzed at 0, 3, 7, 14 and 30 days of storage. Each amino acid was analyzed by amino acid analyzer. Dextrose content was measured by polarimeter. The pH and chromagen formation were also monitored. The decomposition was measured by the changes in concentration of amino acids and dextroser TPN basic $solution-Freamine^{(R)}$ admixture stored at $2\sim8^{\circ}C$ were stable for 30 days. Central and peripheral TPN basic solutions stored at room temperature were stable for 7 days and 14 days, respectively. There were no changes in color for 30 days by naked eye. Amino acid concentrations in TPN basic $solution-Fravasol^{(R)}$ admixture stored at $2\sim8^{\circ}C$ or room temperature were stable for 30 days. But, significant color change was detected according to passing time. In conclusion, Peripheral TPN basic $solution-Fravasol^{(R)}$ admixture stored at room temperature and in refrigerator were stable for 3 days and 7 days, respectively. However, central TPN basic solution-Fravasol admixtures were unstable. Therefore, it is recommended that it should be admixed right before use.

• Journal of Microbiology and Biotechnology
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• v.11 no.2
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• pp.281-286
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• 2001

Since the number of amino groups which are exposed by deacetylation of acetyl-D-glucosamine influences antimicrobial activity, a chitosan oligosaccharide (COS) derivative by N-conjugation of COS with asparagine, an amino acid with two amino groups, was synthesized and the antimicrobial effect on E. coli growth was compared with other COS derivatives which were N-conjugated with glycine, alanine, aspartic acid, cysteins, an methionine, and unmodified COS. The structure of asparagine N-conjugated COS (Asn-COS) derivative was identified by using a FT-IR, $^{13}C\;FT-NMR$, and an elemental analyzer. The antimicrobial activity of Asn-COS against E. coli growth was significantly improved as compared to the other COS derivatives as well as COS itself. This means that Asn-COS with two positive charges strongly interacts with the carboxyl negative charges on the bacteria cell wall. The results for Asn-COS were as follows: 100% bactericidal activity, 0.002% MIC, and no growth of E. coli during 3 days of culture time, suggesting that Asn-COS may be useful as a new antibiotic agent.

• Journal of the East Asian Society of Dietary Life
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• v.26 no.5
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• pp.466-472
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• 2016

The objectives of the study were to analyze the various nutrient contents of ready-to-use-supplemental-food (RUSF) developed with Eastern African ethnic plants and compare them with commercially available supplemental food (CASF) for infants. RUSF was made with three African plants, including Ficus sur, Amaranthus caudatus, and Prosopis juliflorafa and locally available food ingredients in DR Congo and Ethiopia and was cooked at $180^{\circ}C$ for 20 min in a conventional oven. Macronutrients were analyzed by the AOAC method. Contents of 17 amino acids were analysed with amino acid analyzer, and vitamin $B_1%$ niacin, vitamin $B_6$, and vitamin C were analyzed with HPLC. Isomers of vitamin E were analyzed by GC-FID. The price of RUSF was 0.133 USD per 100g. Contents of macronutrients were not significantly different between developed RUSF and CASF. Results of amino acid analysis showed that most amino acid contents were similar or higher in RUSF compared with CASF. However, glutamic acid and lysine contents were less in RUSF than in CASF. Vitamin E and vitamin $B_1$ contents were more than five times higher in RUSF (22.40, 6.26 mg/100 g, respectively) than in CASF (4.00, 0.80 mg/100 g, respectively). Niacin was about three times higher while vitamin $B_6$ was almost 20 times higher in RUSF than in CASF. However, ascorbic acid was significantly lower in RUSF (3.43 mg/100 g) than in CASF (42.08 mg/100 g). Our study found that the developed localized RUSF showed higher nutrient contents in most micronutrients analyzed except for ascorbic acid. Out of 17 amino acids, glutamic acid and lysine contents in RUSF were less than in CASF. Therefore, further study is needed in order to improve these nutrients contents.

• Korean Journal of Agricultural Science
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• v.9 no.2
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• pp.576-583
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• 1982

The variation of free amino acids during the tomato producing was studied using a tomato variety, Kagome 77. The concentration of free amino acids in fresh and heated pulp, and in puree and paste was analyzed by using automatic amino acid analyzer, Hitachi model KLA-5. 1. A significant difference in decomposition rate of glutamine and asparagine among amide group was recognized. For instance, the glutamine decomposed fast and no glutamine was found in the paste, while 56% of asparagine was found in the paste. 2. The diminishing quantity of glutamic acid among acid group was highest among all free amino acids. The quantity of aspartic acid was next to the glutamine. The percents of glutamic acid and aspartic acid left over were 38% and 24%, respectively. 3. Glycine, alanine, valine, isoleucine and leucine of neutral amino acids tended to be reduced a little during the heating, concentrating process. 4. No apparent variation was found for the lysine and histidine belonging to basic amino acids. while arginine increased a little. 5. Tyrosine, phenylalanine and tryptophane of aromatic group seemed to increase a little during the heating process. But the variations of them during the concentrating process were not recognized. 6. The methionine content, sulfur containing amino acid decreased a little throughout the process. But the decrease of ${\gamma}-amino$ butyric acid of non-protein was not apparently recognized. 7. The amino acid contents of fresh pulp were found as following order: glutamic acid>${\gamma}$-amino butyric acid>glutamine>aspartic acid>asparagine. The amino acid contents of paste were as glutamic acid>${\gamma}$-amino butyric acid>aspartic acid and aspargine. The percent distribution of aromatic and basic amino acids increased, even it was not great. 8. When amino acids were analyzed by Hitachi KLA-5, unknown peak which was never app eared in the fresh pulp before tryptophane was appeared when processed. The peak became greater when heated and concentrated. Later it was known that the peak was not due to lysinoalanine or ornithine.

• Korean Journal of Food Science and Technology
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• v.21 no.1
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• pp.58-62
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• 1989

Free amino acids in water-extracts and total amino acids in hydrolysates of three cultivated mushrooms, Agaricus bisporus, Pleurotus ostreatus and Lentinus edodes were analyzed by amino acid analyzer to know the compositional differences depending on species and portions (pileus and stipe). Eighteen amino acids were identified and quantified. The total nitrogen and protein nitrogen contents were in the range of 1.67-6.24% and 0.88-2.42% (dry basis), respectively. The considerable differences were often found among species and portions of mushrooms. All of them were found to be higher in the pileus part. The free amino acids conents in water-extracts were in the range of 10.04-37.85mg/g(dry weight) and the total amino acids contents in hydrolysates were in the range of 53.37-120.15mg/g(dry weight). Glutamic acid, serine, histidine, and alanine were dominent in the free amino acids pool and glutamic, aspartic acid, histidine, and alanine were in the total amino acids pool.

• Journal of the Korean Society of Food Science and Nutrition
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• v.28 no.1
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• pp.9-15
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• 1999

Taurine contents in alcoholic and non alcoholic beverages, milk and milk products, sugars and condiments were determined for 83 food items commonly used by Koreans. Taurine concentrations of food samples were analyzed by using an automated amino acid analyzer(Biochrom 20, Pharmacia LKB) based on ion exchange chromatography. Taurine was not detected in most carbonated beverages, but found in a variety of fruit and vegetable beverages(canned) in the range of 0.13 ~1.43mg taurine/ 100g wt, and in instant coffee or tea beverages(canned) in the range of 0.10~0.41mg taurine/100g wt. The traditional Korean turbid rice wine(takju) sample contained the highest level of taurine (2.29mg/100g wt) among alcoholic beverages tested, which was followed by wine(0.59~0.88mg tau rine/100g wt) and beer(0.53~0.73mg taurine/100g wt). Ordinary milk samples contained 1.05~1.40 mg taurine/100g wt, and a variety of taurine supplemented infant formulas manufactured by Korean companies included 17.3~25.4mg taurine/100g wt. Taurine was not detected in most sugars and sweetners except a couple of chocolate samples(2.13~2.18mg taurine/100g wt). Exceptionally high level of taurine was found in a curry powder sample(16.9mg taurine/100g wt), while the rest of commonly used condiments contained less than 2.90mg taurine/100g wt.