• Journal of Microbiology and Biotechnology
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• v.10 no.1
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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.

• Proceedings of the Korean Society of Rheology Conference
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• 2002.11a
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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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• v.16 no.6
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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.

• Journal of the Korean Chemical Society
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• v.40 no.1
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• pp.87-95
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• 1996

The binary random copolyesters of poly(butylene succinate-co-butylene terephthalate) (PBS/PBT) were synthesized and their sequence distributions were investigated over the entire range for PBS/PBT copolyester compositions by 1H NMR spectroscopy. The melting point (Tm) of these copolyesters were depressed gradually with the increase of dimethyl terephthalate (DMT) mol% in composition and appeared an eutetic behaviour which appears a minimum at ST3 (DMT 65.8 mol%). The melting behaviour of PBS/PBT copolyester was not directly depended on molar fraction (Xa) but on only the sequence propagation probability (P) which occurs in triad fraction. It also can be seen that when the succinate units (or terephthalate units) were abundant enough, PBS/PBT Copolymers formed only PBS (or PBT) crystal with complete rejection of the terephthalate units (or succinate units).

• The Korean Journal of Physiology
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• v.25 no.2
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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.

• The Korean Journal of Pharmacology
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• v.23 no.2
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• pp.113-121
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• 1987

Local anesthetics were investigated for their effects on mitochondrial electron transport system, production of superoxide radical from submitochondrial particles and malondialdehyde production through lipid per oxidation. Local anesthetics had various effects on activities of enzymes in electron transport chain. The activities of NADH dehydrogenase, NADH oxidase and NADH-ubiquinone oxidoreductase were effectively inhibited by lidocaine, procaine and dibucaine but slightly influenced by cocaine. The activities of succinate dehydrogenase, succinate-cytochrome c oxidoreductase and succinate-ubiquinone oxidoreductase were inhibited by lidocaine and dibucaine, but the succinate oxidase activity was stimulated by local anesthetics. Both dihydroubiquinone-cytochrome c oxidoreductase and cytochrome c oxidase activities were inhibited by local anesthetics. In these reactions, the response of Complex I segment to local anesthetics was greater than other Complex segments. Local anesthetics inhibited both the superoxide production from submitochondrial particles supplemented with succinate or NADH and the enhanced production of superoxide radicals by antimycin. The malondialdehyde production by oxygen free radicals was inhibited by local anesthetics. These results suggest that the inhibition of superoxide and malondialdehyde production caused by local anesthetics may be brought by suppression of the electron transport in mitochondria at sites in or near complex I segment.

• Bulletin of the Korean Chemical Society
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• v.35 no.6
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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.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.3
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• pp.323-332
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• 2021

This study was undertaken to develop a new combination tablet containing silodosin and solifenacin succinate for treating urination disorders, for which a simultaneous analytical method of silodosin and solifenacin succinate was established. The aqueous solubility of silodosin and solifenacin succinate was determined to be higher than 1 mg/ml in various buffers, and dissolution of the silodosin and solifenacin succinate commercial products was accomplished within 30 minutes. The drug-excipients compatibility test was subsequently evaluated using differential scanning calorimetry. Excipients without compatibility were selected, and various combination formulations were prepared applying the wet granulation method. Of these, the formulation comprising silodosin, solifenacin succinate, lactose hydrate, MCC PH101, sodium lauryl sulfate (SLS), Povidone K30, crospovidone and magnesium stearate, having a weight ratio of 8/10/56/112/2/6/6/2, respectively, showed equivalence comparative to the dissolution achieved with the commercial products of silodosin (Thrupas tab) and solifenacin succinate (Vesicare tab). Thus, we propose that compared to the currently available commercial products, this novel combination tablet containing silodosin and solifenacin succinate is an effective alternative for the treatment of urination disorders.

• Toxicological Research
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• v.13 no.1_2
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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.

• Journal of Biomedical Engineering Research
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• v.16 no.1
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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.