• Title/Summary/Keyword: Glycine

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Preparation of $(La, Sr)MnO_3$ Powder by Glycine-Nitrate Process Using Oxide as Starting Materials (Glycine-Nitrate Process를 이용한 산화물 출발물질로부터 $(La, Sr)MnO_3$ 분말의 제조)

  • 김재동;문지웅;김구대;김창은
    • Journal of the Korean Ceramic Society
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    • v.34 no.10
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    • pp.1003-1008
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    • 1997
  • The (La, Sr)MnO3 powder used as air-electrode material of Solid Oxide Cell (SOFC) was synthesized by Modified-GNP(Modified-Glycine Nitrate Process). The powders were prepared using oxide and carbonate stable in atmosphere and nitric acid was used as a solvent of starting material as well as an oxidant for combustion. The (La, Sr)MnO3 powders were synthesized with 0.5, 1, 2, 3, 4 of glycine/cation molar ratio. The ICP (Inductively Coupled Plasma Mass Spectrometer) result represented compositional equality between synthesized and desired powders. In case of 2 molar ratio, the as-synthesized powder showed perovskite phase and specific surface area were 19 $m^2$/g. After calcination of 85$0^{\circ}C$, the calcined powder except 0.5, 1 molar ratio of glycine to cation showed perovskite phase.

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The Effects of Different Concentrations of Glycine and Cysteine on the Freezability of Moghani Ram Spermatozoa

  • Khalili, B.;Jafaroghli, M.;Farshad, Abbas;Paresh-Khiavi, M.
    • Asian-Australasian Journal of Animal Sciences
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    • v.23 no.3
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    • pp.318-325
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    • 2010
  • Two experiments were designed to evaluate the effects of the amino acids glycine and cysteine on cryopreservation of ram spermatozoa. After primary evaluation of collected ejaculates, the semen samples were pooled and diluted 1:4 before cooling (experiment 1) and freezing (experiment 2) with Tris-Citrate-Fructose-Yolk (TCFY) extender supplemented with different concentrations of glycine and cysteine (5, 10, 15 and 20 mM). As the control, semen was diluted and frozen in the extender without amino acids. Motility, viability and membrane integrity were assessed as the parameters for semen quality in the first experiment. In the second experiment, motility, progressive motility, viability, membranes and acrosome integrity were evaluated after the freezing-thawing process. The results of the first experiment indicated that the addition of 10 and 15 mM cysteine compared to the control (basic) extender significantly increased (p<0.01) the motility, viability and membrane integrity of spermatozoa after cooling. However, further increasing these amino acids up to 20 mM had a significant negative effect (p<0.05). Our results showed no significant differences (p>0.05) between 5 mM glycine compared to 5 mM cysteine and between 20 mM glycine and 20 mM cysteine. The results of experiment 2 showed that the amino acids significantly improved post-thaw motility, progressive motility, viability, membranes and acrosome integrity of ram spermatozoa. These positive effects were observed at concentrations between 5 to 15 mM of glycine and cysteine, with the best results at 15 mM. Further increasing of amino acid concentrations significantly decreased the post-thaw characteristics of spermatozoa, but the results showed that cysteine was better than glycine and control extenders. The data indicated that addition of glycine or cysteine to the freezing extender can be recommended for cryopreservation of ram spermatozoa. However, further studies are still needed to determine the effect of such addition on fertility in farm animals.

Synthesis and Characterization of Poly(L-lactic acid-co-glycine-L-lactic acid) and Poly - ( L-1actic acid-co-gl ycine-L-methyl 1actic acid) (생체분해성 고분자의 합성 및 물성에 관한 연구(II) -Poly (L-lactic acid-co-glycine-L-lactic acid) 와 Poly- (L-lactic acid-co-glycine-L-methyl lactic acid))

  • Sung, Yong-Kiel;Song, Dae-Kyung;Park, Kyung-Hee
    • Journal of Biomedical Engineering Research
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    • v.9 no.2
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    • pp.225-232
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    • 1988
  • Poly (L- lactic acid-co-glycine-L-lactic acid) and Poly (L-lactic acid-co-glycine-L- methyl lactic acid ) have been prepared by ring opening polymerization. The monomer 6, 6-dimethyl morpho-line-2, 5-dione was synthesized by the bromoisobutylation of 2-bromoisobutyryl bromide with glycin e. L-lactide, 6-methyl morpholine-2, 5-diode. and 6, 6-dimethyl morpholine-2, 5-diode have been used as starting materials for polydepsipeptides. The synthesized monomers and copolymers have been identified by NMR and FT-lR spa- ctrophotometer. The thermal propert ies and glass transition temperature(Tg) of the copolymers have been measured by differential scanning calorimetry. The Tg values of poly(L-lactic acid co-glycine-L-lactic acid) system are increased from $53^{\circ}C\; to\; 107^{\circ}C$ with increasing the mole fraction of 6-methyl morpholine-2, 5-diode. And the Tg values of poly(L-lactic acid co-glycine-L-methyl lactic acid) system are increased from $53^{\circ}C\;to\;138^{\circ}C$ with increasing the mole fraction of 6. 6-dimethyl morpholine-2, 5-diode The thermal stability of poly (L-lactic acid-co-glycine-L-methyl lactic acid) is slightly greta text than that of poly(L-lactic acid-co-glycine-L-lactic acid) due to the methyl group.

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An Overlooked Effect of Glycine Betaine on Fermentation: Prevents Caramelization and Increases the $\small{L}$-Lysine Production

  • Xu, Jianzhong;Xia, Xiuhua;Zhang, Junlan;Guo, Yanfeng;Zhang, Weiguo
    • Journal of Microbiology and Biotechnology
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    • v.24 no.10
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    • pp.1368-1376
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    • 2014
  • This article focuses on the effects of glycine betaine on preventing caramelization, and increasing DCW and $\small{L}$-lysine production. The additional glycine betaine not only decreased the browning intensity (decreased 4 times), and the concentrations of 5-hydroxymethylfurfural (decreased 7.8 times) and furfural (decreased 12 times), but also increased the availability of glucose (increased 17.5%) for $\small{L}$-lysine production. The DCW and $\small{L}$-lysine production were increased by adding no more than 20 mM glycine betaine, whereas the DCW and $\small{L}$-lysine production were decreased with the reduction of pH values, although pH had a better response to prevent caramelization than did glycine betaine. For $\small{L}$-lysine production, the highest increase (40%) was observed on the media with 20 mM glycine betaine. The crucial enzymes in glycolysis and $\small{L}$-lysine biosynthesis pathway were investigated. The results indicated that additional glycine betaine increases the activity of enzymes in glycolysis, in contrast to the effect of pH. All the results indicated that glycine betaine can be used to prevent caramelization and increase the $\small{L}$-lysine production. By applying this strategy, glucose would not be have to be separated from the culture media during autoclaving so that factories can save production costs and shorten the fermentation period.

Effect of Potassium Formate, Glycine and Oxalic Acid in Sulfate Bath on Trivalent Chromium Deposition Composition and Current Efficiency (Potassium formate, Glycine, Oxalic acid가 황화물계 3가 크롬도금층의 조성과 전류효율에 미치는 영향)

  • Kim, Man;Kim, Dae-Young;Park, Sang-Eon;Kwon, Sik-Chul;Choi, Yong
    • Journal of the Korean institute of surface engineering
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    • v.37 no.2
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    • pp.86-91
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    • 2004
  • Effect of potassium formate, glycine and oxalic acid in a sulfate solution on the deposit composition and current efficiency of trivalent chromium plating was studied. The trivalent chromium layers prepared by solutions with potassium formate, glycine and oxalic acid contain a few carbon inside. The solutions containing potassium formate, glycine and oxalic acid are relatively stable with pH change. The solution with the potassium formate shows 6-30% current efficiency with current density, whereas, the solutions with oxalic acid and glycine show about 5% current efficiency, respectively. The improved current efficiency is related to enough supply of chromium ions to the electrode due to the increase of pH at the front of electrode.

Preparation of NiO/YSZ Ultra-Fine Powder Composites Using Self-Sustaining Combustion Process (Self-Sustaining Combustion Process를 이용한 NiO/YSZ 초미세 복합분말 제조)

  • 김선재;정충환;김경호;김영석;국일현
    • Journal of the Korean Ceramic Society
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    • v.33 no.4
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    • pp.411-417
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    • 1996
  • Ultrafine NiO/YSZ (Yttria Stabilized Zirconia) powders were made by using a glycine nitrate process which is used as anode material for solid oxide fuel cells. The specific surface areas of synthesized NiO/YSZ powders were examined with controlling pH of a precursor solution and the content of glycine. The binding of glycine with metal nitrates occurring in the precursor solution was analyzed by using FTIR. The characteristics of synthesized powders were examined with X-ray diffraction(XRD) Brunauer Emmett Teller with N2 absorption. scanning electron microscopy (SEM). and transmission electron microscopy (TEM). Ultrafine NiO/YSZ powders of 15-18 m2/g were obtained through GNP when the content of glycine was controlled to 1 or 2 times the stoichiometric ratio in the precursor solutions. Strongly acid precursor solution increased the specific surface area of the synthesized powders. This is suggested to be the increased binding of metal nitrates and glycine under a strong acid solution of pH=0.5 that lets glycine consist of mainly the amine group of {{{{ { NH}`_{3 } ^{+ } }}. After sintering and reducing treatment of NiO/YSZ powders synthesized by GNP the Ni/YSZ pellet showed ideal microstructure where very fine Ni particles of 3-5 ${\mu}{\textrm}{m}$ were distributed uniformly and fine pore around Ni metal particles was formed. leading to anincrease of the triple phase boundary among gas Ni and YSZ.

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[${^3H}MK-801$ Binding to the Synaptic Membranes of Rat Forebrains: Age-related Regulation by Glutamate, Glycine and Spermine

  • Cho, Jung-Sook;Kong, Jae-Yang
    • The Korean Journal of Physiology and Pharmacology
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    • v.1 no.2
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    • pp.117-125
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    • 1997
  • The N-methyl-D-aspartate (NMDA) receptor-mediated glutamatergic neurotransmission is involved in synaptic plasticity, developmental processes, learning and memory and many neuropathological disorders including age-related diseases. In the present study, regulation of the NMDA receptor properties by various ligands was investigated using $[^3H]MK-801$ binding studies in the synaptic membranes of young and aged rat forebrains. The binding in the presence of glutamate and glycine increased dramatically with growth between 1 and 6 weeks old, and thereafter declined gradually with aging. Glutamate, glycine or spermine respectively increased the binding with growth. Glutamate maintained the binding during aging, while glycine or spermine significantly decreased the binding in the aged brain. The maximum stimulation by glycine varied depending on the ages of brains. Greater sensitivity to glycine was observed at 1 week and 3 months and the sensitivity was significantly reduced in the aged brain. In contrast, spermine showed similar stimulation patterns in young and aged rats. These results indicated that the functional properties of the NMDA receptor-ion channel complex in young and aged rat forebrains are differentially regulated by agonists, and the reduction of the receptor function with normal aging may be, in some degree, due to the reduction of the receptor sensitivity to glycine.

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Browning Pattern and Pigment of Glucose/Glycine Model Systems (글루코스-글리신 혼합용액의 갈색화 패턴 및 색소)

  • Nam, Sang-Sook;Lee, Mie-Soon
    • Korean Journal of Food Science and Technology
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    • v.16 no.2
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    • pp.218-222
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    • 1984
  • Browning pattern was developed in aqueous solutions of glucose/glycine mixture under controlled conditions. Browning pattern was definitely influenced by pH of medium and concentration of reactants. Filter paper disks were immersed in diluted solutions of glucose/glycine system and fried in cooking oil. Concentrations of reactants only affected browning pattern of fried filter paper disks and pH effect was obscured at high temperatures. Amorphous brown precipitate was obtained from the lowest pH medium of glucose/glycine system. An attempt was made to characterize the brown pigment produced in the present model system.

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Distinct $[^3H]$MK-801 Binding Profiles with the Agonist, Partial Agonist, and Antagonist Acting at the Glycine Binding Site of the N-Methyl-D-Aspartate Receptor

  • Cho, Jung-sook;Park, No-Sang;Kong, Jae-Yang
    • Biomolecules & Therapeutics
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    • v.4 no.2
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    • pp.196-201
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    • 1996
  • The N-methyl-D-aspartate (NMDA) receptor-ion channel complex is activated by the simultaneous presence of L-glutamate and glycine, allowing the binding of MK-801 to the phencyclidine (PCP) site of the receptor. The $[^3H]$MK-801 binding assay system was established for determination of pharmacological functions of test compounds acting at the glycine site of the receptor. The binding in the presence of 0.1 $\mu$M L-glutamate was increased by an agonist (glycine) in a dose-dependent fashion, while decreased by either partial agonist (R-(+)-HA-966) or antagonist (5,7-dichlorokynurenic acid: 5,7-DCKA). To distinguish partial agonism from antagonism, various concentrations of 7-chlorokynurenic acid (7-CKA) were added in the assay to eliminate the interference of the endogenous glycine present in the membrane preparations. The bindings in the presence of L-glutamate (0.1$\muM$) and 7-CKA (1, 5, or 10$\muM$) were increased by R-(+)-HA-966. Being a weak partial agonist, the extent of potentiation was much less than that by the agonist. These binding profiles were clearly distinguishable from those by the antagonist, 5,7-DCKA, which exhibited no intrinsic activity. The binding assays established in the present study are a useful system to classify ligands acting at the glycine site of the NMDA receptor by their pharmacological functions.

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Inhibition of Enzymatic Browning of Taro (Colocasia antiquorum var. esculenta) by Maillard Reaction Products from Glycine and Glucose (Glycine과 Glucose의 Maillard Reaction Products에 의한 토란의 효소적 갈변 저해)

  • 이민영;이민경;김춘영;박인식
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.33 no.6
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    • pp.1013-1016
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    • 2004
  • The inhibitory effect of MRPs (Maillard reaction products) on enzymatic browning of taro was investigated. The MRPs prepared by heating glycine and glucose at 9$0^{\circ}C$ for 7 hr exhibited a strong inhibitory effect on taro polyphenol oxidase (PPO). The maximum inhibitory activity of MRPs against taro PPO was detected toward (+)-catechin, catechol, 4-methylcatechol followed by L-$\beta$-3,4-dihydroxyphenylalanine (L-DOPA) and pyragallol as a substrate. The MRPs synthesized from fructose and glucose with glycine as a amino acid significantly reduced the taro PPO activity. MRPs prepared by higher glycine or glucose concentration showed stronger inhibition against taro PPO. Increasing reaction time of the glycine and glucose promoted the inhibitory effect of MRPs against the PPO activity of taro, whereas the color formation was gradually increased.