• 한국식품영양과학회지
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• 제26권3호
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• pp.422-429
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• 1997

For the complete and accurate amino acid determination of protein and food samples, 3 different hydrolysis procedures have been conducted in parallel for each sample, which include the alkaline hydrolysis for tryptophan determination, performic acid oxidation prior to the acid hydrolysis for the determination of cysteine and cystine, and the 6N HCl hydrolysis for the determination of the rest of amino acids. In the present study, amino acid concentrations obtained from the modified single hydrolysis procedure were compared with the values from the conventional hydrolysis procedures in casein and nine food and composite dish samples. In most of the samples tested, the modified single hydrolysis procedure gave significantly higher values of cysteins and cystein compared to the performic acid oxidation method, but resulted in a considerable destruction of tryptophan in food and composited dish samples. There was no consistent difference in the rest of amino acid concentrations between the two hydrolysis systems. Therefore, for complete amino acid determination of various foods and composite dishes, the single hydrolysis method may replace the 6N HCl hydrolysis and performic acid oxidation methods, and thereby reduces 3 hydrolyses to 2 steps with much higher recoveries of the sulfur containing amino acids.

• 한국잠사곤충학회지
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• 제41권1호
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• pp.48-53
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• 1999

불용성 세리신을 가수분해하기 위해 염산 수용액을 이용하여 농도 및 시간별로 처리하여 처리조건이 가수분해에 미치는 영향에 대해 관찰되었다. 가수분해 후 분말화하여 분자량 분포와 분자량 및 백도를 측정하였고, 아미노산 분석을 통하여 세리신의 아미노산 조성의 변화를 시험하여 다음과 같은 결과를 얻었다. 염산 가수분해시 0.5N HCl보다 1N 처리시의 용해도가 5%가량 높았고, 처리 시간이 경과할수록 용해도가 증가하고, 6시간 이상의 처리에서는 그 증가폭이 크지않았다. 가수분해된 세리신의 전기영동 결과는 인정할만한 특정밴드는 나타나지 않았으며 분자량 6,000~20,000 사이에 많이 분포하는 것을 알았다. 가수분해된 세리신의 평균 중합도를 측정한 결과 4.2~5.9이었으며, 이를 분자량으로 환산하면 각각 470~670정도가 된다. 백도는 가수분해 시간이 경과할수록 감소하였다. 가수분해된 세리신의 아미노산 분석시 세리신 가수분해물은 220$^{\circ}C$ 부근의 열변성 피크와 330$^{\circ}C$ 부근의 열분해 피크에서 흡열 피크가 관찰되었다.

• 대한화학회지
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• 제37권1호
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• pp.131-135
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• 1993

2-Amino-3-cyano-6-chloromethylpyrazine으로부터 합성한 methotrexate(MTX) 중간 유도체의 모핵인 pteridine ring의 $C_2$-amino 대신 $HCH_3$기, 또는 $nH_2$기로 치환된 화합물 (7a),(7b)와 (7c)를 두 단계에 걸쳐 합성하였다. 출발물질인 dibenzyl 4,4'-dithiobisbenzoate(12)와 2-amino-3-cyano-6-chloromethylpyrazine으로부터 합성한 2-amino-3-cyano-6-[(S-p-carbenzyloxyphenyl)thiomethyl]-pyrazine(14)화합물을 formamidine HCl, acetamidine HCl과 guanidine HCl 등과 각각 반응시켜 cyclization시키고, 이 화합물을 ethanol 용매하에서 0.2N NaOH를 사용한 알칼리 가수분해로 pteroic acid유도체를 합성하였다.

• 한국토양비료학회지
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• 제45권2호
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• pp.241-247
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• 2012

Many infectious diseases have emerged or re-emerged during the past 50 years in South Korea. There were three outbreaks of foot and mouth disease (FMD) in South Korea between January 2010 and March 2011. Over 3.45 million animals were slaughtered (33.3% of the existing pigs, 8.4% of dairy cows and 3.4% of cattle). To select optimal degradation agents of animal cadavers, degradation rates and fertilizer components of pig cadavers were investigated using hydrogen chloride (HCl), potassium hydroxide (KOH) and sodium hydroxide (NaOH) hydrolysis methods. Degradation rates of pig cadavers using HCl, KOH and NaOH were 81.1, 82.8 and 91.6%, respectively. Total nitrogen (T-N) concentration in degradation solution of pig cadavers using KOH hydrolysis method was higher than that in NaOH and HCl hydrolysis methods. Total phosphorus ($P_2O_5$) concentrations in degradation solution of pig cadavers in all hydrolysis methods ranged 0.14 ~ 0.28%. Total potassium ($K_2O$) concentration for KOH hydrolysis method was higher than that for other hydrolysis methods. The concentration of T-N and $K_2O$ in degradation solution of pig cadavers by KOH hydrolysis method were higher than that in NaOH and HCl hydrolysis methods. Thus, to recycle animal cadavers in agriculture, the optimal degradation agent for hydrolysis was KOH.

• Archives of Pharmacal Research
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• 제4권2호
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• pp.117-122
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• 1981

The carpophores of a mushroom, Naematoloma fasciculare (Fr.) Karst, were extracted with 0.2 N NaOH and the extract was dialyzed through visking tube. It was found to contain an antitumor activity against sarcoma 180 implanted in mice. The components of this aqueous extract were found to be a polysaccharide and a protein by color reactions including Anthrone and Lowery-Folin tests. The hydrolysis of the polysaccharide with 3% HCL-Me-OH and trimethylsily lation of the hydrolysate yielded five monosaccharides, i. e. glucose, frutose, mannose, galactose and xylose, which were detected and analyzed by GLC. After hydrolysis of the protein with 6N HCl, 15 amino acids, including aspartic acid and glutamic acid, were detected and analyzed by an auto amino acid analyzer.

• Journal of Pharmaceutical Investigation
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• 제22권3호
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• pp.185-196
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• 1992

To assess its suitability as a prodrug of 5-fluorouracil (5-FU), 1-glycyloxymethyl-5-FU HCl (GFU), a 5-fluorouracil derivative having a glycyloxymethyl group at the N-l position was synthetized. Its physicochemical properties and hydrolysis kinetics, in aqueous solution of pH $1{\sim}10$ and in the presence of human plasma or rat liver homogenate were studied. Its acute toxicity and antitumor activity against sarcoma 180 were also examined, GFU showed higher lipid/water partition coefficient than 5-FU. The calculated $pK_{\alpha}$ values of 5-FU and GFU were 8.02 and 7,20, respectively. The decomposition rates of GFU in aqueous solution showed a pH-dependence over the pH range used, which could be ascribed to solvent catalysed hydrolysis reaction at pH lower than 4,16 and to specific hydroxide ion hydrolysis reaction at pH higher than 4,16, The half-life of GFU was 6,9 min in 80% human plasma solution and less than 3 min in rat liver homogenate at $37^{\circ}C$, The $LD_{50}$ value of 5-FU was 240 mg/kg while that of GFU was 440.6 mg/kg (226 mg as 5-FU). Both of 5FU and GFU showed a strong antitumor activity, Therapeutic ratios of 5-FU and GFU were 3.07 and 3.55, respectively.

• Bulletin of the Korean Chemical Society
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• 제23권6호
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• pp.824-829
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• 2002

New di-N-cyanomethylated tetraaza macrocycle 2.13-bis(cyanomethyl)-5.16-dimethyl-2,6,13,17-tetraazatricyclo[$16.4.0.0^7.12$]docosane $(L^2)$ has been prepared by the reaction of 3, 14-dimethyl-2,6,13,17-tetraazatricyclo $(L^1)$ with bromoacetonitrile. The square-planar complexes $[ML^2](ClO_4)_2(M=Ni(II)$ or Cu(II) can be prepared by the reaction of $L^2$ with the corresponding metal ion in acetonitrile. The cyanomethyl groups of $[ML^2](ClO_4)_2readily$ react with water to $yield[ML^3](ClO_4)_2$ containing pendant amide groups. The trans-octahedral complexes $[ML^4](ClO_4)_2$, in which two imidate ester groups are coordinated to the metal ion, can be also prepared by the reaction of $[ML^2](ClO_4)_2with$ methanol under mild conditions. The hydrolysis and alcoholysis reactions of $[ML^2](ClO_4)_2are$ promoted by the central metal ion, in spite of the fact that the cyanomethyl group is not involved in intramolecular coordination. The reactions are also promoted by a base such as triethylamine but are retarded by an $acid(HClO_4).Interestingly$, the imidate ester groups of $[ML^4]^2$ are unusually resistant to hydrolysis even in 0.1 M $HCIO_4$ or 0.1 M NaOH aqueous solution. Crystal structure of $[NiL^4](ClO_4)_2shows$ that the Ni-N (pendant imidate ester group) bond is rlatively strong; the Ni-N bond distance is shorter then the Ni-N(tertiary) distance and is similar to the Ni-N (secondary) distance.

• 펄프종이기술
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• 제35권1호
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• pp.27-32
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• 2003

To understand the chemical structure of sewer sludge in comparison with commercial compost and charcoal used as a soil improver, it was carried out to analyse their ash contents and metal ions, and to elucidate the chemical structure of their residuals after a sequential treatment of alcohol-benzene(1:2) extraction in Soxhlet, 3% HCl reflux and 79% H₂SO₄ hydrolysis, using CHNS analyzer and solid C-13 NMR spectrometer. The results obtained were as follows: 1. Ash content of sludge was about 46% that is higher than those of compost (17%) and charcoal (4%). 2. The residual of sludge after a sequential treatment of HCl and H₂SO₄ hydrolyses had high ash content about 23%, too. 3. The sludge seems to be suitable to the soil improver because the content of heavy metal ions in sludge was near the compost and below the organic fertilizer standard. 4. Elemental composition of sludge residual after HCl-H₂SO₄ hydrolyes was C/sub 56/H/sub 91/O/sub 12/N₂S = (C/sub 6/H/sub 10/O/sub 5/)/sub 7/(C/sub 6/H₄)/sub 7/C₂H/sub 43/O₂N₂S, similar to C/sub 103/H/sub 122/O/sub 33/N/sub 6/S = (C/sub 6/H/sub 10/O/sub 5/)/sub 6/(C/sub 6/H₄)/sub 10/C/sub 7/H/sub 22/O₃N/sub 6/S of compost. 5. The sludge residual had proved to have both considerable aliphatic and aromatic groups, but the compost residual to have mainly aliphatic groups and the charcoal to have mainly aromatic groups, through the peak analysis of solid C-13 NMR charts. 6. So, the sewer sludge is proved to have a considerable amount of aromaticity like in woody biomass containing lignin.

• Bulletin of the Korean Chemical Society
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• 제27권8호
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• pp.1194-1198
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• 2006

For the purpose of developing more effective chelating agents, we have synthesized a diethylene triamine pentaacetic acid(DTPA) analogue by using an amino acid. S-(N-Boc-aminophenyl)-Cys(t-Bu4-DTPA) methylester was prepared in 6 steps with total yield of 47.9%. For the sake of introducing a biomolecule to the DTPA derivative, a selective hydrolysis was performed with 3 M HCl/Ethylacetate = 1 : 3 ($25{^{\circ}C}$, 30 min, vigorous stirring). $^{166}Ho$-Cys-DTPA and $^{166}Ho$-Biotin-Cys-DTPA were prepared by mixing $^{166}Ho$ with DTPA derivatives at room temp in a HCl solution (pH = 5) and the radiochemical stabilities (> 99%) were maintained for over 6 hrs in vitro.

• 약학회지
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• 제31권4호
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• pp.219-223
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• 1987

2-Cyclohexylimino-3-cyclohexyl-5-methyl-4-oxo-2H, 5H-1, 3-oxazino [5,6-C]-1, 2-benzothiazine-6,6-dioxide 2 was hydrolized in d-HCl/$CH_3$CN to give 5-methyl-3-cyclohexyl-2H, 5H-1, 3-oxazino [5, 6-C]-1, 2-benzothiazine-2, 4(3H)-dione 6, 6-dioxide 3 in 82% yield. The alkaline hydrolysis of 3 afforded to 4-hydroxy-2-methyl-N-(cyclohexyl)-2H-1, 2-benzothiazine-3-carboxamide-1, 1-dioxide 4 in 88% yield. On the other hand 3 was synthesized from 4 and ethylchloroformate on the reversed procedure.