• Korean Chemical Engineering Research
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• 제56권4호
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• pp.542-546
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• 2018

본 연구에서는 해양 거대조류 중 홍조류에 속하는 꼬시레기(Gracilaria verrucosa)로부터 malonic acid를 사용하여 열수 전처리 조건(전처리 온도, 촉매 농도, 고액비, 전처리 시간)에 따른 전처리와 효소가수분해를 통한 바이오슈거(환원당) 생산 가능성을 조사하였다. 300 mM malonic acid, 1:20 고액비 조건에서 $130^{\circ}C$에서 60분간 전처리를 수행하여 49.2%의 환원당 수율을 얻었다. 전처리 반응 후 이어진 효소 가수분해를 통하여 64.5%의 수율을 확보하였다.

• 한국지하수토양환경학회지:지하수토양환경
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• 제18권7호
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• pp.25-31
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• 2013

Hydrogen peroxide takes much of the cost for Fenton reaction applied for treatment of organic contaminants. Therefore, the effective use of hydrogen peroxide makes the technology more cost effective. The effective use of hydrogen peroxide is especially needed in the soil and groundwater remediation where complete mixing is not possible and it takes a long time for reactive species to transport to the fixed target compounds. Stabilization ability for hydrogen peroxide of malonic acid was evaluated in Fenton and Fenton-like reactions in this study. Malonic acid contributes on the stabilization of hydrogen peroxide by weak interaction between iron and the stabilizer and inhibiting the catalytic role of iron. The stabilization effect increased as the solution pH decrease below the $pK_{a1}$. The stabilization effect increased as the concentration of malonic acid increased and the effect was maximized at the malonic acid concentration of about ten times higher than the iron concentration. The model organic contaminant was successfully oxidized in the presence of the stabilizer but the degradation rate was slower than the system without the stabilizer. The stabilization effect was also proved in a Fenton-like reaction where magnetite and hematite were used instead of soluble iron species.

• Bulletin of the Korean Chemical Society
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• 제30권2호
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• pp.373-377
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• 2009

A pathway for the formation of normal $CoAl_2O_4$ particles is suggested. The optimal amount of malonic acid was determined, and the characteristics of the obtained powders were investigated. Normal $CoAl_2O_4$ powders were prepared using solutions of malonic acid and metal nitrates. X-ray diffraction, Brunauer-Emmett-Teller (BET) and scanning electron microscope (SEM) measurements, as well as Fourier transform infrared (FTIR) and ultraviolet/visible (UV-Vis) spectroscopy were carried out. Normal $CoAl_2O_4$ crystallites were formed by a solid state reaction between $CoAl_2O_4$ and amorphous aluminum oxide. The optimal molar ratio of malonic acid to the nitrate anions present in the initial solution was found to be 0.30~0.35. The particles were composed of agglomerates of primary particles. The primary particles were 40 nm in size. This size was relatively constant regardless of the preparation temperature. However, the size of the agglomerated particles increased to 220 nm with increasing temperature.

• Bulletin of the Korean Chemical Society
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• 제16권2호
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• pp.112-120
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• 1995

The conformational study on malonic acid, hydrogen malonate, malonate, malonyl methyl sulfide, and malonyl methyl sulfide anion, as the model compounds of malonyl-CoA, was carried out using the semiempirical MO methods (MNDO, AM1, and PM3) and hydration shell model. On the whole, the feasible conformations of malonic acid, hydrogen malonate, and malonate seem to be similar to each other. In malonic acid and malonate, two carboxyl groups are nearly perpendicular to the plane of the carbon skeleton, despite of different orientation of two carboxyl groups themselves. In particular, two carboxyl groups of hydrogen malonate are on the plane formed by carbon atoms with an intramolecular hydrogen bond. The calculated results on the geometry and conformation of three compounds are reasonably consistent with those of X-ray and spectroscopic experiments as well as the previous calculations. The orientation of two carbonyl groups of malonyl methyl sulfide is quite similar to that of malonic acid, but different from that of its anion. Especially, the computed probable conformations of the sulfide anion by the three methods are different from each other. The role of hydration seems not to be crucial in stabilizing the overall conformations of malonic acid, hydrogen malonate, malonate, and malonyl methyl sulfide. However, the probable conformations of the unhydrated sulfide anion obtained by the MNDO and AM1 methods become less stabilized by including hydration. The AM1 method seems to be appropriate for conformational study of malonyl-CoA and its model compounds because it does not result in the formation of too strong hydrogen bonds and significant change in conformational energy from one compound to another.

• Applied Biological Chemistry
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• 제8권
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• pp.1-9
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• 1967

Korean soy-sauces were orepared by the ordinary and impreved method and its analyses on the organic acid. The results obtained is as following: 1. In analysing general components of prepared soy-sauce, total acid, volatile acid and non-volatile acid were found more in improved soy-sauce than in ordinary soy-sauce. 2. Volatile organic acid were analysed by gas-chromatography method. As a result, the followings was attained: a) In the ordinary soy-sauce, formic acid, acetic acid, propionic acid, and butyric acid were detected. Butyric acid was in the highest amount and then propionic acid, acetic acid and formic acid are followed in the order. b) In the improved soy-sauce, formic acid, acetic acid, propionic acid and butyric acid were detected. Acetic acid was in the highest amount and then propionic acid, butyric acid and formic acid are followed in the nrder. 3. Non-volatile organic acid were analysed by paper partition chromatography method. As a result, the followings were attained: a) Lactic, glutaric, fumaric, malonic, malic, glycolic, oxalic, tartaric, and succinic acid and two unknown spots were detected in ordinary soysauce. Lactic acid was in the highest amount and then succinic, glycolic, oxalic, tartaric, glutaric, malic, fumaric and malonic acid are followed in the order. b) Lactic, glutaric, malonic, malic, glycolic, tartaric, succinic and tgalacturonic acid and two unknown spots were detected in the improved soy-sauce. Lactic acid was in the highest amount and then succinic, glycolic, malic, glutaric, tartaric, galacturonic and malonic acid are followed in the order. 4. ${\alpha}-keto$ acid were analysed by paper partition chromatography. As a result, the followings were attained: Pyruvic acid and ${\alpha}-keto$ glutaric acid and an unknown spot were detected in the ordinary and improved soy-sauce. Pyruvic acid was in the highest amount and then ${\alpha}-keto$ glutaric acid are ollowed in the order. 5. Stale flavor in the ordinary soy-sauces seems to be partly affected by butyric acid and propionic acid. 6. Substances influencing taste, such as lactic acid and succinic acid, were found more in improved soy-sauce than ordinary soy-sauce.

• 대한화학회지
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• 제38권10호
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• pp.705-709
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• 1994

1M 황산용액에서 세륨(Ⅳ) 이온에 의한 말론산의 산화반응에 관한 반응속도를 분광광도법으로 연구하였다. 말론산이 과량으로 존재하는 조건하에서 측정된 유사일차 속도상수, $k_{obs}$는 말론산의 농도, [MA]에 따라 크게 의존함을 보였으며 $k_{obs}$ = (0.592[MA])/(1+14.5[MA]$^2$)의 관계를 만족하였다. 이에 근거하여 반응메카니즘을 제안하였다. 말론산의 산해리에 의해 생성된 enolate형 음이온과 Ce(Ⅳ)간의 전자이동반응이 반응속도 결정단계이며, MA의 고농도하에서 Ce(Ⅳ)과 enolate형 음이온간의 1:2 chelate생성반응에 의하여 Ce(Ⅳ)의 농도가 감소하여 산화반응이 억제됨을 알 수 있었다. 본 연구에서 제안된 메카니즘에 근거하여 Sengupta 등에 의해 연구된 pH 의존성을 설명할 수 있었다.

• 한국식품과학회지
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• 제17권5호
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• pp.403-405
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• 1985

우리나라산 오가피의 과실, 줄기 및 뿌리중의 지방산 및 유기산의 조성을 분석하였다. 부위별 주요지방산은 oleic, linoleic 및 palmitic acid였으며. 이들 지방산의 함량은 총지방산의 약86-98%를 차지하였다. 그러나 부위에 따라 주요지방산의 함량은 차이가 심하였고 또한 과실의 경우는 품종에 따라 차이가 심하였다. 오가피의 과실에서는 citric, maleic, succinic, malonic, fumaric 및 malic acid등 6종류의 유기산이 분리, 동정되었는데 그중에서 malic acid의 함량이 가장 높았다. 그러나 이들 함량도 지방산과 같이 오가피 품종에 따라 차이가 심하였다. 줄기와 뿌리에서는 과실에서 분리된 유기산 중에서 malonic과 maleic acid가 각각 검출되지 않았으며, citric acid의 함량이 다같이 가장 많았다. 그리고 뿌리 중 총 유기산함량은 과실과 줄기에 비하여 매우 적었다.

• 대한약학회:학술대회논문집
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• 대한약학회 2002년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2
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• pp.232.1-232.1
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• 2002

Methods of 14C-radio isotope labeling of quinolone intermediates at four different sites are described. 14C-radio isotope labeled quinolone intermediates can be synthesized from 14C-1-malonic acid, 14C-2-malonic acid, 14C-benzene ring. and 14C-trimethyl orthoformate. The major site of 14C-radio isotope labeled quinolone intermediates is from 14C-2-malonic acid. We want to help customers to choose the best way for synthesis of 14C-radio isotope labeled quinolone derivatives. and give a general comprehension for 14C-radio isotope labeled pharmaceutical compounds. (omitted)

• Archives of Pharmacal Research
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• 제15권2호
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• pp.184-186
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• 1992

Malonic acid amides were synthesized using different amino acids and their esters. THe synthesized compounds were evaluated for their sedative activity on rats. Potentiating effect of all the compounds on pentobarbitone induced sleep on rats was observed. Plasma protein binding studies were also carried out and it was observed that the synthesized compounds have low plasma protein binding as compared to barbiturates.

• 한국응용과학기술학회지
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• 제23권3호
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• pp.192-198
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• 2006

To provide an aqueous rust inhibitor for metalworking lubricant having low toxicity and excellent rust resistance, we synthesized diester of malonic acid by three consecutive esterifications with over 98% of conversion. This substituted malonic diester could be used as an additive to mineral oil based metalworking lubricant. These metalworking lubricant compositions were showed excellent rust resistance and suitable for various metals and different metalworking processes including hot rolling and cold rolling of aluminum and aluminum alloys.