• Journal of Microbiology and Biotechnology
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• 제10권1호
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• pp.1-7
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• 2000

Bioconversion of fumarate to succinate was anaerobically conduced in a synthetic medium containing glycerol as a hydrogen donor and fumarate as a hydrogen acceptor. We investigated the effects of pH, carbon and nitrogen sources, conversion substrate, and other culture conditions on the production of succinate using a nwely isoloated Enterococcus facalis PKY1. Addition of a variety of carbonates to the medium significantly increasd the rates of production of succinate. The production of succinate and cell growth were relatively satisfactory in the pH range of 7.0-7.6. By using glycerol as a hydrogen donor, high purity succinate was produced with few byproducts. Yeast extract as a sole nitrogen source was the most effective for producing succinalte. As a result, the optimum condition of biconversion was obtained at a medium containing 20g/I glycerol, 50 g/l fumarate, 15 g/l yeast extract, 10 g/l $K_2HPO_4$, 1 g/I NaCl, 50ppm $MgCl_2{\cdot}6H_2O$, 10ppm $FeSo_4{\cdot}7H_2O$, and 5 g/I $Na_2CO_3$ at pH 7.0-7.6. Under the optimum condition, a succinate concentration of 153 g/I was produced in 36 h. The total volumetric production rate and the molar yield of succinate were 4.3 g/l/h and 85%, respectively.

• 한국유변학회:학술대회논문집
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• 한국유변학회 2002년도 추계학술발표회 논문집
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• pp.163-166
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• 2002

No Abstract, See Full Text

• Journal of Microbiology and Biotechnology
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• 제16권6호
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• pp.870-879
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• 2006

The present study describes the formation of succinic acid by a nonvirulent, highly osmotolerant Klebsiella pneumoniae strain SAP (succinic acid producer), its profile of metabolites, and enzymes of the succinate production pathway. The strain produced succinate along with other metabolites such as lactate, acetate, and ethanol under aerobic as well as anaerobic growth conditions. The yield of succinate was higher in the presence of $MgCO_3$ under $N_2$ atmosphere as compared with that under $CO_2$ atmosphere. Analysis of intracellular metabolites showed the presence of a smaller PEP pool than that of pyruvate. Oxaloacetate, citrate, and $\alpha$-ketoglutarate pools were considerably larger than those of isocitrate and fumarate. In order to understand the synthesis of succinate, the enzymes involved in end-product formation were studied. Levels of phosphoenolpyruvate carboxykinase, fumarate reductase, pyruvate kinase, and acetate kinase were higher under anaerobic growth conditions. Based on the profiles of the metabolites and enzymes, it was concluded that the synthesis of succinate took place via oxaloacetate, malate, and fumarate in the strain under anaerobic growth conditions. The strain SAP showed potential for the bioconversion of fumarate to succinate under $N_2$ atmosphere in the presence of $MgCO_3$. At an initial fumarate concentration of 10 g/l, 7.1 g/l fumarate was converted to 7 g/l succinate with a molar conversion efficiency of 97.3%. The conversion efficiency and succinate yield were increased in the presence of glucose. Cells grown on fumarate contained an 18-fold higher fumarate reductase activity as compared with the activity obtained when grown on glucose.

• 대한화학회지
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• 제40권1호
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• pp.87-95
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• 1996

이성분계 rendom copolyeseters인 Poly(butylene succinate-co-butylene terephthalate)(PBS/PBT)를 합성하고 $^1H$ NMR spectroecopy를 이용하여 전 조성범위에 걸쳐 sepuence distribution을 조사하였다. PBS/PBT 공중합물의 융점(Tm)은 공중합물내 dimethyl terephthalate(DMT)의 함량이 증가함에 따라 점차적으로 감소하는 현상을 나타냈고 ST3(DMT 65.8mol%)에서 최저융점(eutetic point) 거동을 보였다. 이러한 공중합물의 융점거동은 공중합물의 몰분율(Xa)보다는 triad fraction으로 계산된 sequence propagation probability(P)에 더욱 의존하는 경향을 보였다. 또한 succinate unit(또는 terephthalate unit)의 함량이 많은 공중합물들은 terephthalate unit(또는 succinate unit)를 완전히 배제시키면서 단지 PBS(또는PBT)만의 결정을 형성하였다.

• The Korean Journal of Physiology
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• 제25권2호
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• pp.179-188
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• 1991

Effect of a sulfhydryl reagent, p-chloromercuribenzoic acid (PCMB), on the transport of succinate was studied in brush border (BBMV) and basolateral (BLMV) membrane vesicles isolated from rabbit renal cortex. PCMB induced an irreversible inhibition of the $Na^+-dependent$ succinate uptake in a dose-dependent manner with $IC_{50}$ of 55 and $65\;{\mu}M$ in BBMV and BLMV, respectively. The inhibitory effect of PCMB was prevented by a pretreatment of vesicles with dithiothreitol. PCMB did not increase $Na^+$ permeability at concentrations inhibiting succinate uptake. The PCMB inhibition of succinate uptake was due to a change in Vmax, but not in Km. When membrane vesicles were pretreated with PCMB in the presence of unlabelled succinate, the inhibitory effect was significantly reduced. In both BBMV and BLMV, succinate uptake was inhibited by various sulfhydryl reagents with the inhibitory potency of following order: $HgCl_2$>DTNB>PCMBS>PCMB. These results suggest that sulfhydryl groups are essential for dicarboxylate transport and that they may be located at or near substrate binding sites of the transporters in renal brush border and basolateral membranes.

• 대한약리학회지
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• 제23권2호
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• pp.113-121
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• 1987

국소마취제가 mitochondria에서의 전자이동 및 superoxide라디칼의 생성 그리고 지질의 과산화에 따른 malondialdehyde생성에 미치는 영향을 관찰하였다. 국소마취제는 전자이동계 의 효소활성도에 영향을 나타내었다. NADH dehydrogenase, NADH oxidase와 NADH-ubiquinone oxidoreductase의 활성도는 lidocaine, procaine과 dibucaine에 의하여 효과적으로 억제되었고 cocaine에 의하여 약간 억제되었다. Succinate dehydrogenase, succinate cytochrome c oxidoreductase와 succinate-ubiquinone oxidoreductase 활성도는 lidocaine 과 dibucaine에 의하여 억제되었으나 succinate oxidase는 국소마취제에 의하여 활성화되었다. 국소마취제는 dihydroubiquinone-cytochrome c oxidoreducatse와 cytochrome c oxidase의 활성도를 억제하였다. 이와 같은 반응에서 국소마취제에 대한 complex I segment의 반응이 다른 complex segment보다 크게 나타났다. 국소마취제는 succinate 또는 NADH에 의한 superoxide 생성과 이에 대한 antimycin의 자극효과를 억제하였다. 또한 국소마취제는 산소라디칼에 의한 지질의 과산화를 억제하였다. 이상의 결과로부터 국소마취제는 mitochondria의 전자전달 과정 중 Complex I segment때 또는 인접한 부위에 작용하여 전자이동을 억제함으로써 superoxide 생성과 지질의 과산화를 억제할 것으로 시사되었다.

• Bulletin of the Korean Chemical Society
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• 제35권6호
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• pp.1777-1783
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• 2014

Four $Cd^{II}$ MOFs, $[Cd_2({\mu}-succinate)_2(H_2O)_2]{\cdot}H_2O$ (1A), $[Cd_2({\mu}-succinate)_2({\mu}-4,4^{\prime}-bpy)_2]{\cdot}H_2O$ (1B), $[\{Cd_2({\mu}-succinate)_2\}({\mu}-bpa)_2\{Cd(H_2O)_2\}(NO_3)_2]{\cdot}H_2O$ (2), and $[Cd({\mu}-succinate)({\mu}-bpp)_2]{\cdot}2H_2O$ (3), with various bipyridyl ligands (4,4'-bipyridine (4,4'-bpy), 1,2-bis(4-pyridyl)ethane (bpa), and 1,3-bis(4-pyridyl)propane (bpp)) were prepared, and their structures were determined using X-ray crystallography. The structures and dimensionalities of $Cd^{II}$-(succinate) compounds varied depending on the auxiliary ligands. Heterogeneous catalytic activity for transesterification reactions, photoluminescence and the thermal stabilities of these compounds were also examined.

• 한국산학기술학회논문지
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• 제22권3호
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• pp.323-332
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• 2021

본 연구의 목적은 배뇨장애 치료를 위한 실로도신과 솔리페나신 숙신산염을 함유한 새로운 복합 정제를 개발하는 것이다. 이러한 목표를 달성하기 위하여 실로도신과 솔리페나신 숙신산염의 동시 정량법을 확립하였다. 두 약물은 다양한 완충액에서 1 mg/ml 이상의 수용해도 값을 나타내었으며, 실로도신과 솔리페나신 숙신산염이 함유된 시판제품의 용출은 다양한 용출조건에서 30분 이내에 완료되었다. 시차 주사 열량계를 사용하여 부형제와 약물 간 상호 반응성을 확인하여 선정된, 약물과 반응성이 없는 부형제를 사용하여 습식 과립화 방법을 사용하여 결합제와 붕해제의 사용에 따른 다양한 처방을 제조한 후 용출시험을 진행하였다. 제조한 정제의 처방 중 실로도신, 솔리페나신 숙신산염, 유당, 미결정셀룰로오스 PH101, 소듐라우릴설페이트, 포비돈 K-30, 크로스포비돈 및 스테아린산마그네슘이 8/10/56/112/2/6/6/2(w/w)의 비율로 제조된 정제는 트루패스정(실로도신 시판 제품) 및 베시케어정(솔리페나신 숙신산염 시판 제품)과의 비교용출 시험시 동등성을 나타내는 것을 확인하였다. 따라서, 본 연구를 통해 얻어진 복합 정제는 각 약물의 시판 제품과 동등한 생체이용률을 나타낼 수 있을 것으로 판단되며, 향후 배뇨 장애 치료에 복약순응도가 우수한 의약품으로 활용될 수 있을 것으로 사료된다.

• Toxicological Research
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• 제13권1_2호
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• pp.167-173
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• 1997

LBD-001, a recombinant human interferon $\gamma$ produced by genetically engineered yeast as a host system, was intravenously administered to pregnant female rabbits (New Zealand White strain) from day 6 to 18 of gestation at dose levels of $0.35 \times 10^6$, $0. 69 \times 10^6$, and $1.38 \times 10^6$ I.U./kg/day. Hydrocortisone sodium succinate (0.3 mg/kg/day) was also given in the same way. Teratological effects of the test agents on the organogenesis of fetuses and the development of offsprings (F1 rabbits) were investigated. The results were as followings: (1) No significant changes by the treatment of LBD-001 or hydrocortisone sodium succinate were observed in the body weights, the food and water consumption, the lactating or nurshing behaviors, and the autopsy of the pregnant rabbits. (2) No significant changes in the resorption rate, the fetal organogenesis, and the normal develpoment of offsprings (F1) by the treatment of LBD-001 or hydrocortisone sodium succinate were detected. The results show that LBD-001 at the dose of $1.38 \times 10^6$ I.U./kg/day or less and hydrocortisone sodium succinate at the dose of 0.3 mg/kg/day are neither teratogenic in the organogensis of the fetuses and the development of the offsprings (F1) nor toxic to the mother rabbits.

• 대한의용생체공학회:의공학회지
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• 제16권1호
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• pp.9-16
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• 1995

Biodegradable poly (I ,4-butanediol succinate) (PBS) was synthesized from 1,4-butanediol and succinic anhydride. The glass transition temperature of poly (I, 4-butanediol succinate) was revealed at $73^{\circ}C$. The crystallization and cold crystallization of the polymers were investigated as a function of holding time in melt state, cooling rate. reheating, and molecular weight. Chain scission and/or cmsslinking did not occur in the melt state at var.ious holding times. Slower scanning rate can allow more times for nucleation, rearrangement, and packing of the polymer chain, so the onset temperature of crystallization from the melt was increased. PBS crystallized from the melt was found to have spherulitic structure. The degradation behavior of PBS was studied under basic conditions and with microorganisms using the modified ASTM method. In the basic solution. PBS lost up to 85% of its mass within two days. Based upon visual observation, the crystalline structure of films composed of larger molecular weight polymers retained their crystallinity longer than similar structures in low molecular weight samples.