• Title/Summary/Keyword: Amino-acid

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Chromatographic Enantiomer Separation and Determination of Optical Purity for α-Amino Acid Esters as 9-Anthraldimine Derivatives Using Polysaccharide Based Chiral Columns (다당 유도체를 기초로 한 키랄 컬럼에서 아미노산 에스테르의 안트르알디민 유도체의 광학분리 및 광학순도 측정)

  • Huang, Hu;Jin, Jing-Yu;Lee, Won-Jae
    • KSBB Journal
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    • v.26 no.2
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    • pp.139-142
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    • 2011
  • The chromatographic enantiomer separation of 9-anthraldimine derivatives of ${\alpha}$-amino acid methyl and ethyl esters on four polysaccharide based chiral columns was performed. The 9-anthraldehyde Schiff base derivatives of ${\alpha}$- amino acid esters were readily synthesized by stirring the ${\alpha}$- amino acid ester hydrochloride salts with 9-anthraldehyde in the presence of 1,8-diazabicyclo [5.4.0]undec-7-ene as a base and anhydrous $MgSO_4$. Chiralcel OD or Chiralcel OD-H showed the greatest enantiomer resolution of 9-anthraldimine derivatives of ${\alpha}$-amino acid methyl and ethyl esters. The L-enantiomers of all the analytes were preferentially retained on Chiralcel OD or Chiralcel OD-H. This analytical method was applied in the determination of optical purities of several commercially available D- or L-${\alpha}$-amino acid methyl esters.

Liquid Chromatographic Resolution of α-Amino Acid Esters as Benzophenone Imine Derivatives (아미노산 에스테르의 벤조피논 이민 유도체의 액체 크로마토그래피의 광학분리)

  • Yun, Won-Nam;Xu, Wen Jun;Huang, Hu;Lee, Won-Jae
    • KSBB Journal
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    • v.27 no.3
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    • pp.167-171
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    • 2012
  • A convenient liquid chromatographic enantiomer separation of several ${\alpha}$-amino acid esters as benzophenone Schiff base derivatives on covalently immobilized chiral stationary phases (CSPs) derived from polysaccharide derivatives was developed. The benzophenone imine derivatives of ${\alpha}$-amino acid esters were readily prepared by stirring benzophenone imine and the ${\alpha}$-amino acid ester hydrochloride salts in 2-propanol. The chromatographic conditions used on all CSPs were 0.5% or 5% 2-propanol/hexane (V/V) as the mobile phases at 1 mL/min of flow rate and UV 254 nm detection. The performance of Chiralpak IC among all CSPs was superior to that of the other CSPs for resolution of benzophenone imine derivatives of ${\alpha}$-amino acid esters. It is expected that the developed analytical method will be useful for enantiomer resolution of other ${\alpha}$-amino acid esters as benzophenone Schiff base derivatives.

Enantiomer Separation of α-Amino Acid Esters as Nitrobenzoxadiazole Derivatives Using Chiral Columns (키랄 컬럼을 사용한 아미노산 에스테르의 니트로벤조옥사디아졸 유도체의 광학분리)

  • Yun, Won Nam;Kim, Ji Yeon;Lee, Wonjae
    • KSBB Journal
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    • v.28 no.6
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    • pp.423-427
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    • 2013
  • A new convenient derivatization method of ${\alpha}$-amino acid esters as nitrobenzoxadiazole (NBD) derivatives for chiral resolution was introduced and the enantiomer separation of ${\alpha}$-amino acid esters as NBD derivatives was performed by normal HPLC using chiral columns based on polysaccharide derivatives. The NBD derivatives were readily prepared by stirring NBD-Cl and ${\alpha}$-amino acid methyl ester HCl with $NaHCO_3$ in ethanol. The performance of Chiralpak IA was superior to the other chiral stationary phases for enantiomer resolution of NBD derivatives of several ${\alpha}$-amino acid methyl esters. Owing to fluorescence detection as well as strong UV absorption, it is expected that the convenient analytical method developed in this study will be very useful for enantiomer separation of ${\alpha}$-amino acid esters as NBD derivatives on polysaccharide-derived chiral columns.

Studies on the Amino Acid Constituents of Gynostemma pentaphyllum Makino (돌외 (Gynostemma pentaphyllum Makino)의 아미노산(酸) 조성(組成)에 관(關)한 연구(硏究))

  • Kim, Sun-Hee;Park, Won-Ki
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.17 no.1
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    • pp.7-11
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    • 1988
  • This study was carried out in order to analyse the amino acid constituents of Gynostemma pentaphyllum Makino (G. P. M. ) produced in Korea and Japan. Total and free amino acids of those were analysed by HPLC. Total amino acid contents of G. P. M. produced in Korea were similar to that of produced in Japan. The Histidine content of G. P. M. produced in Korea was more rich than that of produced in Japan. The content of glutamic acid was the most rich among in kinds of amino acids in both hind of G. P. M. G. P. M. in Korea contained the least methionine and G. P. M. from Japan contained the least cystine.

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Effects of Amino Acid in In-vitro Maturation Medium on Nuclear Maturation and Embryo Development of Korean Native Cow (체외성숙 배지에 아미노산의 첨가가 한우 난포란의 핵성숙과 배발달에 미치는 영향)

  • 박용수;김소섭;최수호;박노찬;변명대;박흠대
    • Reproductive and Developmental Biology
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    • v.28 no.1
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    • pp.29-36
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    • 2004
  • The objective of this study was to investigate the effects of amino acid supplementation of oocyte maturation medium on 1st polar body(PB) extrusion, embryo development and blastocsyt cell number. In experiment 1, Cumulus oocyte complexes(COCs) were matured in in vitro maturation(IVM) medium supplemented with 1, 2, or 4-fold of 10 $\mu$l/ml MEM non-essential amino acid(NEAA) and 20 Park, $\mu$ l/ml BME essential amino acid(EAA). The PB extrusion rate of oocytes matured in 1-fold amino acid group was significantly higher than that matured in medium without amino acid (p<0.05), but it was decreased by the increase of the dosage of amino acid. There were no difference in the percentage of embryos reaching 2-cell, 8-cell and blastocyst in all treatments. The number of trophectoderm(TE) cells and total cell number of blastocysts were highest in 2-fold amino acid group, and the number of inner cell mass(ICM) cells was increased by the increase of the dosage of amino acid. In experiment 2, COCs were matured in IVM medium with 1, 5, or 10 mg/ml lactalbumin hydrolysate(LAH). The PB extrusion rate of oocytes matured in medium with 5 mg LAH was significantly higher than that matured in medium with 1 mg LAH (p<0.05). The development rate to the blastocyst stage was significantly higher in non-supplement and 1 mg LAH group than in 5 mg and 10 mg LAH group (p<0.05). The number of TE cells and total cell number did not differ among treatment groups, but the number of ICM cells was increased by the increase of LAH supplement. These results suggested that the supplement of certain group of amino acid in IVM medium effective on the quality of blastocyst, and further studies will be accompany with the search of new sources of amino acid used for the use of in vitro embryo production.

Determination of Active Site in PRD1 DNA Polymerase by Site-specific Mutagenesis (Site-specific Mutagenesis에 의한 PRD1 DNA Polymerase의 활성부위 결정)

  • 황정원;정구홍
    • Korean Journal of Microbiology
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    • v.29 no.4
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    • pp.209-214
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    • 1991
  • The PRD1 DNA polymerase is a small multi-functional enzyme containing conserved amino acid sequences shared by family B DNA polymerases. Thus the PRD1 DNA polymerase provides an useful model system with which to study structure-functional relationships of DNA polymerase molecules. In order to investigate the functional and structural roles of the highly conserved amino acid sequences, we have introduced three mutations into a conserved amino acid of the PRD1 DNA polymerase. Genetic complememtation study indicated that each mutation inactivated DNA polymerase catalytic activity.

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Egg Quality and Amino Acid Composition of Fertilized Eggs of Sevenband Grouper, Epinephelus septemfasciatus per Farming Condition (사육조건에 따른 능성어, Epinephelus septemfasciatus, 수정란의 난질 및 아미노산 조성)

  • Kim, Kyong Min;Cho, Jae Kwon;Park, Jong Youn;Son, Maeng Hyun;Park, Jae Min;Han, Kyeong Ho;Hong, Chang Gi
    • Korean Journal of Ichthyology
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    • v.28 no.4
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    • pp.229-238
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    • 2016
  • This study aims to investigate egg quality and amino acid composition of buoyant and non-buoyant eggs and evaluate egg quality of sevenband grouper, Epinephelus septemfasciatus. Amino acid analysis of eggs was conducted to investigate what elements were necessary for the survival and good quality of egg depending on farming condition and different diet. We analyzed amino acid from buoyant eggs and non-buoyant eggs, farming conditions (tank and sea cage), and different dietary conditions (formulated feed, formulated feed+raw fish-based moist pellets, and raw fish-based moist pellets). Egg quality was the best in a sea cage and when raw fish-based moist pellets (MP) were fed. In addition, egg quality with formulated and MP was better than that with formulated feed. As a result of amino acid analysis of eggs, buoyant eggs were containing more free amino acid than non-buoyant eggs. Also, eggs with MP were containing more free amino acid than those with formulated feed and MP. Eggs with mixed formulated feed and MP were containing more free amino acid than formulated feed. In conclusion, amino acid was helpful to improve egg quality, and egg quality can be controlled by farming conditions and feed.

Amino Acid Properties and Sensory Characteristics of Chicken Stock by Different Salt Contents (소금 첨가량을 달리한 닭 육수의 아미노산 조성 및 관능적 특성)

  • Kim, Doog-Seok;Kim, Jog-Seck;Seoung, Tae-Jong
    • Culinary science and hospitality research
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    • v.16 no.4
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    • pp.274-285
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    • 2010
  • This study attempts to develop a mass production product standardized by the application of high pressure extraction cooking(HPEC) in order to suggest a desirable direction for the development of salt contained standardized chicken stock. In our experiment on chicken stock with varying its salt content, the total free amino acid content was highest in S3, which contained 0.3% of salt In addition, when the total content of free amino acid was divided into the contents of essential amino acid, palatable amino acid, and other types of amino acid, they showed the same distribution as the total content of free amino acid. In addition, the total content of palatable amino acid was highest among the specimens. In the results of investigating the palatability of chicken stock according to salt content, saltiness increased with the increase of the salt content, but no significant difference was observed in preference for saltiness. It is believed to have come from the difference in the sensory evaluators' preference for saltiness, and it shows that the salt content has an effect on sweet taste, delicate taste, fishy smell, and color. In particular, specimen 83, which contained 0.3% of salt, showed the highest content of palatable amino acid, and the highest level of delicate taste in sensory tests, suggesting the correlation between palatable amino acid and delicate taste.

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A Study on the Separation of Electrolyte from Amino Acid Solution through Electrodialysis (전기투석법을 이용한 아미노산으로부터 전해질 분리정제에 관한 연구)

  • 김석곤;한정우;김한성;전경용;조영일
    • Membrane Journal
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    • v.4 no.3
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    • pp.163-170
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    • 1994
  • The separation of inorganic salt from amino acid solution using was performed electrodialysis. In order to review the availability of electrodialysis using isoelectric point of amino acid as a bio-separation technique, electrodialysis stacks were designed using ion exchange membrane. Separation of NaCl from amino acid solution was performed in the condition similar to amino acid fermentation process. To obtain otimum conditions of separation, leakage of amino acid depending of pH and limiting current density were measured. On the basis of optimum condition, removal of NaCl and leakage of amino acid were investigated quantitatively in batch and continuous process, and current efficiencies were also obtained. As a result of batch experiment for 11 hours each amino acid solution, removal efficiencies of NaCl were in the ranges of 96.1~96.2%. Amino acid leakage rate of glycine, methionine, alanine were 2.5, 1.7, 2.0% respectively. Current efficiencies were in the ranges of 44.5~44.6%. As a result of continuous experiment in various flow rate of each amino acid solution, it took 120 ~ 150 min to reach to steady state. Removal efficiency of NaCl was increased as the flow rate was decreased, but current efficiency was decreased. At the steady states, there were no leakage of amino acid.

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The amino acid contents of wild mushrooms in Korea (국내 야생수집 버섯의 아미노산 함량 분석)

  • An, Gi-Hong;Cho, Jae-Han;Han, Jae-Gu
    • Journal of Mushroom
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    • v.18 no.1
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    • pp.107-114
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    • 2020
  • Fifteen species of wild mushrooms, which are classified as edible, medicinal, poisonous, or unknown types, were analyzed for their free amino acid contents. The average total amino acid content was 1,120.0 mg/kg in the edible type, 1,037.8 mg/kg in the medicinal type, and 1,010.8 mg/kg in the poisonous or unknown type, respectively. The edible type wild mushrooms showed the highest average content of total essential amino acids; conversely, the poisonous or unknown type showed the lowest content. Leucopaxillus giganteus (OK811) showed the highest total amino acid (1,212.4 mg/kg) and essential amino acid (490.2 mg/kg) contents among edible type, while Pycnoporus sanguineus (OK1071) showed the highest total amino acid (1,233.7 mg/kg) and essential amino acid (412.8 mg/kg) contents among the medicinal type. Among the poisonous or unknown type, Hypholoma fasciculare (OK826) showed the highest total amino acid (1,223.4 mg/kg) and essential amino acid (442.8 mg/kg) contents. The amino acid contents of wild mushrooms are fundamental data for the screening of useful genetic resources with nutritionally superior properties.