• Journal of Microbiology and Biotechnology
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• v.17 no.2
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• pp.218-225
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• 2007

A lactic acid bacterium capable of anaerobic respiration was isolated from soil with ferric iron-containing glucose basal medium and identified as L. garvieae by using 16S rDNA sequence homology. The isolate reduced ferric iron, nitrate, and fumarate to ferrous iron, nitrite, and succinate, respectively, under anaerobic $N_2$ atmosphere. Growth of the isolate was increased about 30-39% in glucose basal medium containing nitrate and fumarate, but not in the medium containing ferric iron. Specifically, metabolic reduction of nitrate and fumarate is thought to be controlled by the specific genes fnr, encoding FNR-like protein, and nir, regulating fumarate-nitrate reductase. Reduction activity of ferric iron by the isolate was estimated physiologically, enzymologically, and electrochemically. The results obtained led us to propose that the isolate metabolized nitrate and fumarate as an electron acceptor and has specific enzymes capable of reducing ferric iron in coupling with anaerobic respiration.

• Journal of Microbiology and Biotechnology
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• v.26 no.3
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• pp.558-566
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• 2016

Biotic agents such as fumarate-reducing bacteria can be used for controlling methane (CH₄) production in the rumen. Fumarate-reducing bacteria convert fumarate to succinate by fumarate reductase, ultimately leading to the production of propionate. Fumarate-reducing bacteria in the genus Enterococcus were isolated from rumen fluid samples from slaughtered Korean native goats. The enterococci were identified as Enterococcus faecalis SROD5 and E. faecium SROD by phylogenetic analyses of 16S rRNA gene sequences. The fumarate reductase activities of the SROD5 and SROD strains were 42.13 and 37.05 mM NADH oxidized/min/mg of cellular nitrogen (N), respectively. Supplementation of rumen fermentation in vitro with the SROD5 and SROD strains produced significantly higher propionate, butyrate, and total volatile fatty acid (VFA) concentrations than controls at 12 h; VFA concentrations tended to increase after 24 h of incubation. The generated CH₄ concentration was significantly lower in the SROD5 and SROD treatment groups after 24 h of incubation. These findings indicate that E. faecium SROD has potential as a direct-fed microbial additive for increasing total VFAs while decreasing CH₄ production in rumen fermentation in vitro.

• Journal of Korean Society on Water Environment
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• v.21 no.6
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• pp.630-636
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• 2005

Groundwater contamination by nitrate exceeding water quality criteria (10 mg $NO_3{^-}-N/L$) occurs frequently. Fumarate, acetate, formate, lactate, propionate, ethanol, methane and hydrogen gas were evaluated for their nitrate removal efficiencies and removal rates for in situ bioremediation of nitrate contaminated groundwater. Denitrification rate for each substrate was in the order of: fumarate > hydrogen > formate/lactate > ethanol > propionate > methanol > acetate. Microcosm studies were performed with fumarate and acetate. When fumarate was used as a substrate, nitrate was removed 100 percent with rate of 0.66 mmol/day while conversion rate from nitrate to nitrogen gas or another by-product was 87 percent. 42 mg of fumarate was needed to remove 30 mg $NO_3{^-}-N/L$. When using acetate as carbon source, 31 percent of nitrate was removed during initial adjustment period. Among removed fraction, however, 83 percent of nitrate removed by cell growth. Overall nitrate removal rate was 0.37 mmol/day. Acetate showed longer lag time in consumption compared to that of nitrate, which implying that acetate would be better carbon source compared to fumarate as more amount was utilized for nitrate removal than cell growth.

• 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.

• KSBB Journal
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• v.15 no.3
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• pp.318-322
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• 2000

An oxygen-sensitive fumarate reductase has been purified from the cytosol fraction of the Enterococcus faecalis RKY1 grown anaerobically on a defined medium containing glycerol and fumarate. A major portion of the purification was performed with employing Triton X-100 and reducing agents by Phenyl-sepharose CL-4B DEAE-sepharose and Dephadex G-150 The final activity was 0.42 unit/mg. The deduced molecular mass of active band was 66 kDa. The optimal pH and temperature for the activity were 7.0 and 38$^{\circ}C$ respectively. The enzyme activity was not affected by 1mM metal ions such as bacl2 $.$2H2O HgCl2 MnCl2$.$4H2O ZnCl2 CuCl2$.$2H2O Mgcl2$.$6H2O FeSo4$.$7H2O and by EDTA. Partially purified enzyme ws yellow in color ; spectroscopic study indicated the presence of flavins as a cofactor.

• Journal of Pharmaceutical Investigation
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• v.17 no.2
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• pp.79-88
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• 1987

In order to reduce gastric irritation of iron preparations, one prodrug, glycine complex of ferrous fumarate, was synthesized, identified, examined for physico-chemical properties and compared with ferrous fumarate, ferrous sulfate and ferroglycine sulfate. That novel ferroglycine fumarate (FGF) resulted in higher dissolution rate in water, artificial gastric and intestinal juice. The absorption rate constants $(K_a)$ in rat of FGF was greater and ulcerogenic dose on stomach was increased remarkably than those of iron parent materials and ferroglycine sulfate.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2003.04a
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• pp.192-195
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• 2003

As a part of our research project for in-situ bioremediation of nitrate contaminated. groundwater, screening studies to determine an effective electron donor (EO) and/or carbon source (CS) such as acetate, ethanol, formate, fumarate, lactate, and propionate were conducted. To evaluate the feasibility for the biological degradation of nitrate, soil microcosm studies using nitrate-contaminated soil and groundwater were performed. The nitrate removal percentage in the order from the highest to the lowest was: formate, fumarate, and ethanol > lactate > propionate. Essentially no nitrate consumption was observed In acetate-fed microcosms. The order of nitrate removal rate from the highest to lowest was fumarate, formate, lactate, ethanol, and propionate. These results suggest that fumarate and formate are promising EDs/CSs for in-situ bioremediation of nitrate - contaminated oxygenated groundwater.

• Asian-Australasian Journal of Animal Sciences
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• v.20 no.4
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• pp.543-549
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• 2007

Two experiments were conducted to investigate the effects of disodium fumarate on the in vitro rumen fermentation profiles of different substrates and microbial communities. In experiment 1, nine diets (high-forage diet (forage:concentrate, e.g. F:C = 7:3, DM basis), medium-forage diet (F:C = 5:5, DM basis), low-forage diet(F:C = 1:9, DM basis), cracked corn, cracked wheat, soluble starch, tall elata (Festuca elata), perennial ryegrass and rice straw) were fermented in vitro by rumen microorganisms from local goats. The results showed that during 24 h incubations, for all substrates, disodium fumarate increased (p<0.05) the gas production, and tended to increase (p<0.10) the acetate, propionate and total VFA concentration and decrease the ratio of acetate to propionate, whereas no treatment effect was observed for the lactate concentration. The apparent DM loss for tall elata, perennial ryegrass and rice straw increased (p<0.05) with the addition of disodium fumarate. With the exception of tall elata, perennial ryegrass and rice straw, disodium fumarate addition increased the final pH (p<0.05) for all substrates. In experiment 2, three substrates (a high-forage diet, a medium-forage diet and a high concentrate diet) were fermented by mixed rumen microbes in vitro. A polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) technique was applied to compare microbial DNA fingerprints between substrates at the end of 24 h incubation. The results showed that when Festuca elata was used as substrate, the control and disodium fumarate treatments had similar DGGE profiles, with their similarities higher than 96%. As the ratio of concentrate increased, however, the similarities in DGGE profiles decreased between the control and disodium fumarate treatment. Overall, these results suggest that disodium fumarate is effective in increasing the pH and gas production for the diets differing in forage: concentrate ratio, grain cereals and soluble starch, and in increasing dry matter loss for the forages (tall elata, perennial ryegrass and rice straw) in vitro, whereas its effect on changes of ruminal microbial community may largely depend on the general nature of the substrate.

• Korean Journal of Microbiology
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• v.47 no.2
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• pp.174-178
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• 2011

In Escherichia coli, DcuS/R two-component system controls fumarate import and utilization related gene expression. To understand the dynamic response of the bacterium DcuS/R two-component system with respect to fumarate concentrations, DcuS/R induced dctA promoter was integrated with GFP reporter protein. Expression monitoring study using recombinant strain showed that dctA promoter was upregulated with 1 mM of fumarate in M9 minimal medium.

• Journal of Nutrition and Health
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• v.31 no.5
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• pp.914-920
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• 1998

The effect of dietary pectin, tangerine pulp meal, propionate, lactate or fumarate on cholesterol (C) and triacylglycerol(TG) levels in the serum and liver, and the effect of pectin on dietary C absorption were studied in a series of three experiments. Mature female Sprague Dawley rats were fed a control diet or diets containing 5% pectin, 5% tangerine pulp meal, 3% propionate, 3% lactate 3% fumarate, or 10% pectin. Serum total C levels were lower(p<0.05) in rats fed the diet containing 5% pectin than in control rats after a 4-week feeding period(93.8 vs 119.2mg/100mL). Serum HDL, LDL+VLDL C levels were not different among diet groups. Liver total C level was also lower(p<0.05) in rats fed the diet containing 5% pectin than in control rats, but liver TG level was not influenced by diet. Dietary propionate, lactate or fumarate did not reduce serum C, indicating that propionate is not a regulator of serum C. However, dietary pectin(10%) increased fecal excretion of dietary C(or its metabolites) more than 70% over a control value. Our data indicate that dietary pectin reduces serum and liver C levels by increased fecal secretion of dietary C, but not by its fermentation product propionate or other gluconeogenic substrates. (Korean J Nutrition 31(5) : 914∼920, 1998)