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Sample records for acetate propionate succinate

  1. Inhibition of the Fermentation of Propionate to Methane by Hydrogen, Acetate, and Propionate

    PubMed Central

    Fukuzaki, Satoshi; Nishio, Naomichi; Shobayashi, Manabu; Nagai, Shiro

    1990-01-01

    Inhibition of the fermentation of propionate to methane and carbon dioxide by hydrogen, acetate, and propionate was analyzed with a mesophilic propionate-acclimatized sludge that consisted of numerous flocs (size, 150 to 300 μm). The acclimatized sludge could convert propionate to methane and carbon dioxide stoichiometrically without accumulating hydrogen and acetate in a propionate-minimal medium. Inhibition of propionate utilization by propionate could be analyzed by a second-order substrate inhibition model (shown below) given that the substrate saturation constant, Ks, was 15.9 μM; the substrate inhibition constant, Ki, was 0.79 mM; and the maximum specific rate of propionate utilization, qm, was 2.15 mmol/g of mixed-liquor volatile suspended solids (MLVSS) per day: qs = qmS/[Ks + S + (S2/Ki)], where qs is the specific rate of propionate utilization and S is the initial concentration of undissociated propionic acid. For inhibition by hydrogen and acetate to propionate utilization, a noncompetitive product inhibition model was used: qs = qm/[1 + (P/Kp)n], where P is the initial concentration of hydrogen or undissociated acetic acid and Kp is the inhibition constant. Kinetic analysis gave, for hydrogen inhibition, Kp(H2) = 0.11 atm (= 11.1 kPa, 71.5 μM), qm = 2.40 mmol/g of MLVSS per day, and n = 1.51 and, for acetate inhibition, Kp(HAc) = 48.6 μM, qm = 1.85 mmol/g of MLVSS per day, and n = 0.96. It could be concluded that the increase in undissociated propionic acid concentration was a key factor in inhibition of propionate utilization and that hydrogen and acetate cooperatively inhibited propionate degradation, suggesting that hydrogenotrophic and acetoclastic methanogens might play an important role in enhancing propionate degradation to methane and carbon dioxide. PMID:16348146

  2. Engineering Propionibacterium freudenreichii subsp. shermanii for enhanced propionic acid fermentation: effects of overexpressing propionyl-CoA:Succinate CoA transferase.

    PubMed

    Wang, Zhongqiang; Ammar, Ehab M; Zhang, An; Wang, Liqun; Lin, Meng; Yang, Shang-Tian

    2015-01-01

    Propionibacterium freudenreichii subsp. shermanii naturally forms propionic acid as the main fermentation product with acetate and succinate as two major by-products. In this study, overexpressing the native propionyl-CoA:succinate CoA transferase (CoAT) in P. shermanii was investigated to evaluate its effects on propionic acid fermentation with glucose, glycerol, and their mixtures as carbon source. In general, the mutant produced more propionic acid, with up to 10% increase in yield (0.62 vs. 0.56g/g) and 46% increase in productivity (0.41 vs. 0.28g/Lh), depending on the fermentation conditions. The mutant also produced less acetate and succinate, with the ratios of propionate to acetate (P/A) and succinate (P/S) in the final product increased 50% and 23%, respectively, in the co-fermentation of glucose/glycerol. Metabolic flux analysis elucidated that CoAT overexpression diverted more carbon fluxes toward propionic acid, resulting in higher propionic acid purity and a preference for glycerol over glucose as carbon source.

  3. Isolation of acetic, propionic and butyric acid-forming bacteria from biogas plants.

    PubMed

    Cibis, Katharina Gabriela; Gneipel, Armin; König, Helmut

    2016-02-20

    In this study, acetic, propionic and butyric acid-forming bacteria were isolated from thermophilic and mesophilic biogas plants (BGP) located in Germany. The fermenters were fed with maize silage and cattle or swine manure. Furthermore, pressurized laboratory fermenters digesting maize silage were sampled. Enrichment cultures for the isolation of acid-forming bacteria were grown in minimal medium supplemented with one of the following carbon sources: Na(+)-dl-lactate, succinate, ethanol, glycerol, glucose or a mixture of amino acids. These substrates could be converted by the isolates to acetic, propionic or butyric acid. In total, 49 isolates were obtained, which belonged to the phyla Firmicutes, Tenericutes or Thermotogae. According to 16S rRNA gene sequences, most isolates were related to Clostridium sporosphaeroides, Defluviitoga tunisiensis and Dendrosporobacter quercicolus. Acetic, propionic or butyric acid were produced in cultures of isolates affiliated to Bacillus thermoamylovorans, Clostridium aminovalericum, Clostridium cochlearium/Clostridium tetani, C. sporosphaeroides, D. quercicolus, Proteiniborus ethanoligenes, Selenomonas bovis and Tepidanaerobacter sp. Isolates related to Thermoanaerobacterium thermosaccharolyticum produced acetic, butyric and lactic acid, and isolates related to D. tunisiensis formed acetic acid. Specific primer sets targeting 16S rRNA gene sequences were designed and used for real-time quantitative PCR (qPCR). The isolates were physiologically characterized and their role in BGP discussed.

  4. Propionate stimulates pyruvate oxidation in the presence of acetate

    PubMed Central

    Purmal, Colin; Kucejova, Blanka; Sherry, A. Dean; Burgess, Shawn C.; Malloy, Craig. R.

    2014-01-01

    Flux through pyruvate dehydrogenase (PDH) in the heart may be reduced by various forms of injury to the myocardium, or by oxidation of alternative substrates in normal heart tissue. It is important to distinguish these two mechanisms because imaging of flux through PDH based on the appearance of hyperpolarized (HP) [13C]bicarbonate derived from HP [1-13C]pyruvate has been proposed as a method for identifying viable myocardium. The efficacy of propionate for increasing PDH flux in the setting of PDH inhibition by an alternative substrate was studied using isotopomer analysis paired with exams using HP [1-13C]pyruvate. Hearts from C57/bl6 mice were supplied with acetate (2 mM) and glucose (8.25 mM). 13C NMR spectra were acquired in a cryogenically cooled probe at 14.1 Tesla. After addition of hyperpolarized [1-13C]pyruvate, 13C NMR signals from lactate, alanine, malate, and aspartate were easily detected, in addition to small signals from bicarbonate and CO2. The addition of propionate (2 mM) increased appearance of HP [13C]bicarbonate >30-fold without change in O2 consumption. Isotopomer analysis of extracts from the freeze-clamped hearts indicated that acetate was the preferred substrate for energy production, glucose contribution to energy production was minimal, and anaplerosis was stimulated in the presence of propionate. Under conditions where production of acetyl-CoA is dominated by the availability of an alternative substrate, acetate, propionate markedly stimulated PDH flux as detected by the appearance of hyperpolarized [13C]bicarbonate from metabolism of hyperpolarized [1-13C]pyruvate. PMID:25320331

  5. Propionate stimulates pyruvate oxidation in the presence of acetate.

    PubMed

    Purmal, Colin; Kucejova, Blanka; Sherry, A Dean; Burgess, Shawn C; Malloy, Craig R; Merritt, Matthew E

    2014-10-15

    Flux through pyruvate dehydrogenase (PDH) in the heart may be reduced by various forms of injury to the myocardium, or by oxidation of alternative substrates in normal heart tissue. It is important to distinguish these two mechanisms because imaging of flux through PDH based on the appearance of hyperpolarized (HP) [(13)C]bicarbonate derived from HP [1-(13)C]pyruvate has been proposed as a method for identifying viable myocardium. The efficacy of propionate for increasing PDH flux in the setting of PDH inhibition by an alternative substrate was studied using isotopomer analysis paired with exams using HP [1-(13)C]pyruvate. Hearts from C57/bl6 mice were supplied with acetate (2 mM) and glucose (8.25 mM). (13)C NMR spectra were acquired in a cryogenically cooled probe at 14.1 Tesla. After addition of hyperpolarized [1-(13)C]pyruvate, (13)C NMR signals from lactate, alanine, malate, and aspartate were easily detected, in addition to small signals from bicarbonate and CO2. The addition of propionate (2 mM) increased appearance of HP [(13)C]bicarbonate >30-fold without change in O2 consumption. Isotopomer analysis of extracts from the freeze-clamped hearts indicated that acetate was the preferred substrate for energy production, glucose contribution to energy production was minimal, and anaplerosis was stimulated in the presence of propionate. Under conditions where production of acetyl-CoA is dominated by the availability of an alternative substrate, acetate, propionate markedly stimulated PDH flux as detected by the appearance of hyperpolarized [(13)C]bicarbonate from metabolism of hyperpolarized [1-(13)C]pyruvate.

  6. Ketotifen controlled release from cellulose acetate propionate and cellulose acetate butyrate membranes.

    PubMed

    Sobral, Manuela C C M; Sobral, Abilio J F N; Guthrie, J T; Gil, M H

    2008-02-01

    Ketotifen was immobilised in cellulose acetate propionate (CAP) membranes and in cellulose acetate butyrate (CAB) membranes. The characteristics of each system were evaluated under a range of experimental conditions. The topography and uniformity of the membranes was assessed using scanning electron microscopy. The release characteristics associated with Ketotifen were monitored spectrophotometrically. The swelling capacity of the membranes was evaluated and attributed to the combined effects of diffusion and of complex dissociation, during swelling. The materials produced were able to provide controlled release of Ketotifen due to their controlled swelling behaviour and adequate release properties. The results showed that the release of Ketotifen from the CAB membranes is higher but the release from the CAP membranes is more uniform.

  7. Acetate but not propionate induces oxidative stress in bakers' yeast Saccharomyces cerevisiae.

    PubMed

    Semchyshyn, Halyna M; Abrat, Oleksandra B; Miedzobrodzki, Jacek; Inoue, Yoshiharu; Lushchak, Volodymyr I

    2011-01-01

    The influence of acetic and propionic acids on baker's yeast was investigated in order to expand our understanding of the effect of weak organic acid food preservatives on eukaryotic cells. Both acids decreased yeast survival in a concentration-dependent manner, but with different efficiencies. The acids inhibited the fluorescein efflux from yeast cells. The inhibition constant of fluorescein extrusion from cells treated with acetate was significantly lower in parental strain than in either PDR12 (ABC-transporter Pdr12p) or WAR1 (transcriptional factor of Pdr12p) defective mutants. The constants of inhibition by propionate were virtually the same in all strains used. Yeast exposure to acetate increased the level of oxidized proteins and the activity of antioxidant enzymes, while propionate did not change these parameters. This suggests that various mechanisms underlie the yeast toxicity by acetic and propionic acids. Our studies with mutant cells clearly indicated the involvement of Yap1p transcriptional regulator and de novo protein synthesis in superoxide dismutase up-regulation by acetate. The up-regulation of catalase was Yap1p independent. Yeast pre-incubation with low concentrations of H₂O₂ caused cellular cross-protection against high concentrations of acetate. The results are discussed from the point of view that acetate induces a prooxidant effect in vivo, whereas propionate does not.

  8. Biosynthesis of the Juvenile Hormones of Manduca sexta: Labeling Pattern from Mevalonate, Propionate, and Acetate

    PubMed Central

    Schooley, David A.; Judy, Kenneth J.; Bergot, B. John; Hall, M. Sharon; Siddall, John B.

    1973-01-01

    Using organ culture, high-resolution liquid chromatography, and microchemical techniques, we demonstrated the efficient incorporation in vitro of several radiolabeled precursors into the two juvenile hormones of Manduca sexta. JH II, a homosesquiterpene hormone, reported from M. sexta as well as several other insects, incorporates radiolabel from acetate, mevalonate, and propionate. JH III, a sesquiterpene hormone recently reported as a natural product of M. sexta, incorporates label from acetate and mevalonate, but not from propionate. Based on the position of the labeled atoms in the precursors and upon the position of incorporation obtained from label-distribution data, a scheme for juvenile hormone biosynthesis is advanced. PMID:16592112

  9. Homogeneous preparation of cellulose acetate propionate (CAP) and cellulose acetate butyrate (CAB) from sugarcane bagasse cellulose in ionic liquid.

    PubMed

    Huang, Kelin; Wang, Ben; Cao, Yan; Li, Huiquan; Wang, Jinshu; Lin, Weijiang; Mu, Chaoshi; Liao, Dankui

    2011-05-25

    Cellulose acetate butyrate (CAB) and cellulose acetate propionate (CAP) were prepared homogeneously in a 1-allyl-3-methylimidazolium chloride (AmimCl) ionic liquid system from sugarcane bagasse (SB). The reaction temperature, reaction time, and molar ratio of butyric (propionic) anhydride/anhydroglucose units in the cellulose affect the butyryl (B) or propionyl (P) content of CAB or CAP samples. The (13)C NMR data revealed the distribution of the substituents of CAB and CAP. The thermal stability of sugar cane bagasse cellulose was found by thermogravimetric analysis to have decreased after chemical modification. After reaction, the ionic liquid was effectively recycled and reused. This study provides a new way for high-value-added utilization of SB and realizing the objective of turning waste into wealth.

  10. A novel fermentation pathway in an Escherichia coli mutant producing succinic acid, acetic acid, and ethanol.

    SciTech Connect

    Donnelly, M. I.; Millard, C. S.; Clark, D. P.; Chen, M. J.; Rathke, J. W.; Southern Illinois Univ.

    1998-04-01

    Escherichia coli strain NZN111, which is unable to grow fermentatively because of insertional inactivation of the genes encoding pyruvate: formate lyase and the fermentative lactate dehydrogenase, gave rise spontaneously to a chromosomal mutation that restored its ability to ferment glucose. The mutant strain, named AFP111, fermented glucose more slowly than did its wild-type ancestor, strain W1485, and generated a very different spectrum of products. AFP111 produced succinic acid, acetic acid, and ethanol in proportions of approx 2:1:1. Calculations of carbon and electron balances accounted fully for the observed products; 1 mol of glucose was converted to 1 mol of succinic acid and 0.5 mol each of acetic acid and ethanol. The data support the emergence in E.coli of a novel succinic acid:acetic acid:ethanol fermentation pathway.

  11. Chicory increases acetate turnover, but not propionate and butyrate peripheral turnovers in rats.

    PubMed

    Pouteau, Etienne; Rochat, Florence; Jann, Alfred; Meirim, Isabelle; Sanchez-Garcia, Jose-Luis; Ornstein, Kurt; German, Bruce; Ballèvre, Olivier

    2008-02-01

    Chicory roots are rich in inulin that is degraded into SCFA in the caecum and colon. Whole-body SCFA metabolism was investigated in rats during food deprivation and postprandial states. After 22 h of food deprivation, sixteen rats received an IV injection of radioactive 14C-labelled SCFA. The volume of distribution and the fractional clearance rate of SCFA were 0.25-0.27 litres/kg and 5.4-5.9 %/min, respectively. The half-life in the first extracellular rapidly decaying compartment was between 0.9 and 1.4 min. After 22 h of food deprivation, another seventeen rats received a primed continuous IV infusion of 13C-labelled SCFA for 2 h. Isotope enrichment (13C) of SCFA was determined in peripheral arterial blood by MS. Peripheral acetate, propionate and butyrate turnover rates were 29, 4 and 0.3 micromol/kg per min respectively. Following 4 weeks of treatment with chicory root or control diets, eighteen fed rats received a primed continuous IV infusion of 13C-labelled SCFA for 2 h. Intestinal degradation of dietary chicory lowered caecal pH, enhanced caecal and colonic weights, caecal SCFA concentrations and breath H2. The diet with chicory supplementation enhanced peripheral acetate turnover by 25 % (P = 0.017) concomitant with an increase in plasma acetate concentration. There were no changes in propionate or butyrate turnovers. In conclusion, by setting up a multi-tracer approach to simultaneously assess the turnovers of acetate, propionate and butyrate it was demonstrated that a chronic chicory-rich diet significantly increases peripheral acetate turnover but not that of propionate or butyrate in rats.

  12. Pathways of acetate, propionate, and butyrate formation by the human fecal microbial flora.

    PubMed

    Miller, T L; Wolin, M J

    1996-05-01

    The pathways of short-chain fatty acid (SCFA; acetate, propionate, and butyrate) formation from glucose were determined for the human fecal microbial communities of two subjects. The pathways were identified by radioisotope analysis of the SCFA and CO2 obtained after incubation of fecal suspensions with glucose under 20% CO2 with [1-14C]glucose, [3,4-14C]glucose, or 14CO2. Acetate was chemically degraded to learn the labeling of the methyl and carboxyl carbons. The labeling of CO2 and acetate showed that the major route of glucose catabolism was the Embden-Meyerhof-Parnas pathway, with production of CO2 from pyruvate carboxyl carbon. Labeling of the methyl and carboxyl carbons of acetate by 14CO2 or [3,4-14C]glucose proved that acetate was formed from CO2 by the Wood-Ljungdahl pathway. CO2 reduction accounted for about one-third of the acetate formed by suspensions from subject 1 and about one-fourth of the acetate formed by suspensions from subject 2. Propionate was formed by a CO2 fixation pathway, and butyrate was formed by classical routes of acetyl-S coenzyme A condensation. The amount of CO2 formed from [1-14C] glucose and acetate labeling patterns obtained with the other 14C precursors indicated that the Entner-Doudoroff, transketolase-transaldolase, and heterolactic pathways were not significant. Fermentation of cabbage cellulose by subject 1 followed the same pathways as were used for glucose. The results with suspensions from subject 2 suggested that some radioactive acetate was formed from the C-3 of glucose by the Bifidobacterium pathway.

  13. Effect of acetate and octanoate on tricarboxylic acid cycle metabolite disposal during propionate oxidation in the perfused rat heart.

    PubMed

    Sundqvist, K E; Peuhkurinen, K J; Hiltunen, J K; Hassinen, I E

    1984-10-16

    Tricarboxylic acid cycle pool size is determined by anaplerosis and metabolite disposal. The regulation of the latter during propionate metabolism was studied in isolated perfused rat hearts in the light of the characteristics of NADP-linked malic enzyme, which is inhibited by acetyl-CoA. The acetyl-CoA concentration was varied by infusions of acetate and octanoate, and the rate of metabolite disposal was calculated from a metabolic balance sheet compiled from the relevant metabolic fluxes. Propionate addition increased the tricarboxylic acid cycle pool size 4-fold and co-infusion of acetate or octanoate did not change it further. Propionate caused a decrease in the CoA-SH concentration and a 10-fold increase in the propionyl-CoA concentration. A paradoxical increase in the CoA-SH concentration was observed upon co-infusion of acetate in the presence of propionate, an effect probably caused by competitive inhibition of propionate activation. A more pronounced decline in the propionyl-CoA concentration was observed upon the co-infusion of octanoate. In a metabolic steady state, acetate and octanoate reduced propionate disposal only slightly, but did not increase the tricarboxylic acid cycle pool size. The results are in accord with the notion that the tricarboxylic acid pool size is mainly regulated by the anaplerotic mechanisms.

  14. Investigation of griseofulvin and hydroxypropylmethyl cellulose acetate succinate miscibility in ball milled solid dispersions.

    PubMed

    Al-Obaidi, Hisham; Lawrence, M Jayne; Al-Saden, Noor; Ke, Peng

    2013-02-25

    Solid dispersions of varying weight ratios compositions of the nonionic drug, griseofulvin and the hydrophilic, anionic polymer, hydroxylpropylmethyl cellulose acetate succinate, have been prepared by ball milling and the resulting samples characterized using a combination of Fourier transform infra-red spectroscopy, X-ray powder diffraction and differential scanning calorimetry. The results suggest that griseofulvin forms hydrogen bonds with the hydroxylpropylmethyl cellulose acetate succinate polymer when prepared in the form of a solid dispersion but not when prepared in a physical mixture of the same composition. As anticipated, the actual measured glass transition temperature of the solid dispersions displayed a linear relationship between that predicted using the Gordon-Taylor and Fox equations assuming ideal mixing, but interestingly only at griseofulvin contents less than 50 wt%. At griseofulvin concentrations greater than this, the measured glass transition temperature of the solid dispersions was almost constant. Furthermore, the crystalline content of the solid dispersions, as determined by differential scanning calorimetry and X-ray powder diffraction followed a similar trend in that the crystalline content significantly decreased at ratios less than 50 wt% of griseofulvin. When the physical mixtures of griseofulvin and the hydroxylpropylmethyl cellulose acetate succinate polymer were analyzed using the Flory-Huggins model, a negative free energy of mixing with an interaction parameter of -0.23 were obtained. Taken together these results suggest that anionic hydrophilic hydroxylpropylmethyl cellulose acetate succinate polymer is a good solvent for crystalline nonionic griseofulvin with the solubility of griseofulvin in the solid dispersion being was estimated to be within the range 40-50 wt%. Below this solubility limit, the amorphous drug exists as amorphous glassy solution while above these values the system is supersaturated and glassy suspension and

  15. Dynamics of microbial community structure of and enhanced biological phosphorus removal by aerobic granules cultivated on propionate or acetate.

    PubMed

    Gonzalez-Gil, Graciela; Holliger, Christof

    2011-11-01

    Aerobic granules are dense microbial aggregates with the potential to replace floccular sludge for the treatment of wastewaters. In bubble-column sequencing batch reactors, distinct microbial populations dominated propionate- and acetate-cultivated aerobic granules after 50 days of reactor operation when only carbon removal was detected. Propionate granules were dominated by Zoogloea (40%), Acidovorax, and Thiothrix, whereas acetate granules were mainly dominated by Thiothrix (60%). Thereafter, an exponential increase in enhanced biological phosphorus removal (EBPR) activity was observed in the propionate granules, but a linear and erratic increase was detected in the acetate ones. Besides Accumulibacter and Competibacter, other bacterial populations found in both granules were associated with Chloroflexus and Acidovorax. The EBPR activity in the propionate granules was high and stable, whereas EBPR in the acetate granules was erratic throughout the study and suffered from a deterioration period that could be readily reversed by inducing hydrolysis of polyphosphate in presumably saturated Accumulibacter cells. Using a new ppk1 gene-based dual terminal-restriction fragment length polymorphism (T-RFLP) approach revealed that Accumulibacter diversity was highest in the floccular sludge inoculum but that when granules were formed, propionate readily favored the dominance of Accumulibacter type IIA. In contrast, acetate granules exhibited transient shifts between type I and type II before the granules were dominated by Accumulibacter type IIA. However, ppk1 gene sequences from acetate granules clustered separately from those of propionate granules. Our data indicate that the mere presence of Accumulibacter is not enough to have consistently high EBPR but that the type of Accumulibacter determines the robustness of the phosphate removal process.

  16. [Kinetic model of enhanced biological phosphorus removal with mixed acetic and propionic acids as carbon sources. (III): Model application].

    PubMed

    Zhang, Chao; Chen, Yin-Guang

    2013-03-01

    The kinetic model based on SCFAs metabolism was applied for the prediction of phosphorus-and glycogen-accumulating organisms (PAO and GAO) competition with different carbon sources and m(P)/m(COD) ratios. When acetic acid was used as the sole carbon source, the biomass compositions were almost the same as those before cultivation, and neither PAO nor GAO could be out-competed from EBPR. However, increasing propionic acid in the influent helped PAO to be the predominance organism, and EBPR performance kept excellent when the ratio of propionate to mixed acids (acetate + propionate) was higher than 0.33. It also found that the m(P)/m(COD) ratio should be kept at 0.04-0.10 to avoid phosphorus became a limiting factor for PAO growth. This was because at low m(P)/m(COD) ratios, such as 0.01, GAO would take up 95% of the total (PAO + GAO) biomass.

  17. Partition coefficients for acetic, propionic, and butyric acids in a crude oil/water system

    SciTech Connect

    Reinsel, M.A.; Borkowski, J.J.; Sears, J.T. . National Science Foundation Engineering Research Center for Biofilm Engineering)

    1994-07-01

    The effects of pH, temperature, and organic acid concentration on the partition coefficients for short-chain organic acids were measured in a crude oil/water system. Acetic, propionic, and butyric acids, as probable substrates for microbial souring of oil reservoirs, were used in conjunction with two types of crude oil. Temperatures of 35--75 C, pH values of 4.0--7.0, and acid concentrations of 10--1,000 mg/L were studied. Initial naturally occurring levels of organic acids in the crude oils were also determined. pH had by far the largest effect on the partition coefficient for all three organic acids for both types oil. At conditions normally seen in an oil reservoir (pH 5--7), the great percentage (85+%) of these acids were dissolved in the aqueous phase. The log of the partition coefficient K increased approximately linearly with the number of carbon atoms in the acid. It was seen that organic acids are readily available carbon sources for sulfate-reducing bacteria (SRB) at normal reservoir conditions, and that crude oil may provide a source of organic acids in a low-pH, water-flooded reservoir.

  18. Structure and Rotational Dynamics of Isoamyl Acetate and Methyl Propionate Studied by Microwave Spectroscopy

    NASA Astrophysics Data System (ADS)

    Stahl, W.; Nguyen, H. V. L.; Sutikdja, L. W.; Jelisavac, D.; Mouhib, H.; Kleiner, I.

    2012-06-01

    The microwave spectra of a number of organic aliphatic esters have been recorded for the first time in the 3-26.5 GHz frequency range, using the molecular beam Fourier-transform microwave (MB-FTMW) spectrometer in Aachen, with an instrumental uncertainty of a few kHz for unblended lines. The combined use of ab initio quantum chemical calculations and spectral analysis allowed us to determine the spectroscopic parameters and potential barriers to internal rotation of the methyl groups for the lowest energy conformers. We will compare here the results from ab initio calculations and from two different hamiltonian methods (the XIAM and BELGI codes) for isoamyl acetate H3C-COO-(CH2)2-CH(CH3)2, an one-top internal rotor molecule with a C1 symmetry and for methyl propionate CH3CH2COOCH3 containing two inequivalent methyl tops (C3v), with different barrier heights. This study is part of a larger project which aims at determining the structures of the lowest energy conformers for a serie of organic esters and ketones which are of interest for flavour or perfume applications.

  19. Quantifying Effect of Lactic, Acetic, and Propionic Acids on Growth of Molds Isolated from Spoiled Bakery Products.

    PubMed

    Dagnas, Stéphane; Gauvry, Emilie; Onno, Bernard; Membré, Jeanne-Marie

    2015-09-01

    The combined effect of undissociated lactic acid (0 to 180 mmol/liter), acetic acid (0 to 60 mmol/liter), and propionic acid (0 to 12 mmol/liter) on growth of the molds Aspergillus niger, Penicillium corylophilum, and Eurotium repens was quantified at pH 3.8 and 25°C on malt extract agar acid medium. The impact of these acids on lag time for growth (λ) was quantified through a gamma model based on the MIC. The impact of these acids on radial growth rate (μ) was analyzed statistically through polynomial regression. Concerning λ, propionic acid exhibited a stronger inhibitory effect (MIC of 8 to 20 mmol/liter depending on the mold species) than did acetic acid (MIC of 23 to 72 mmol/liter). The lactic acid effect was null on E. repens and inhibitory on A. niger and P. corylophilum. These results were validated using independent sets of data for the three acids at pH 3.8 but for only acetic and propionic acids at pH 4.5. Concerning μ, the effect of acetic and propionic acids was slightly inhibitory for A. niger and P. corylophilum but was not significant for E. repens. In contrast, lactic acid promoted radial growth of all three molds. The gamma terms developed here for these acids will be incorporated in a predictive model for temperature, water activity, and acid. More generally, results for μ and λ will be used to identify and evaluate solutions for controlling bakery product spoilage.

  20. Modification of wheat starch with succinic acid/acetic anhydride and azelaic acid/acetic anhydride mixtures I. Thermophysical and pasting properties.

    PubMed

    Subarić, Drago; Ačkar, Durđica; Babić, Jurislav; Sakač, Nikola; Jozinović, Antun

    2014-10-01

    The aim of this research was to investigate the influence of modification with succinic acid/acetic anhydride and azelaic acid/acetic anhydride mixtures on thermophysical and pasting properties of wheat starch. Starch was isolated from two wheat varieties and modified with mixtures of succinic acid and acetic anhydride, and azelaic acid and acetic anhydride in 4, 6 and 8 % (w/w). Thermophysical, pasting properties, swelling power, solubility and amylose content of modified starches were determined. The results showed that modifications with mixtures of afore mentioned dicarboxylic acids with acetic anhydride decreased gelatinisation and pasting temperatures. Gelatinisation enthalpy of Golubica starch increased, while of Srpanjka starch decreased by modifications. Retrogradation after 7 and 14 day-storage at 4 °C decreased after modifications of both starches. Maximum, hot and cold paste viscosity of both starches increased, while stability during shearing at high temperatures decreased. % setback of starches modified with azelaic acid/acetic anhydride mixture decreased. Swelling power and solubility of both starches increased by both modifications.

  1. Application of finite inverse gas chromatography in hypromellose acetate succinate-water-acetone systems.

    PubMed

    Chiu, Sheng-Wei; Sturm, Derek R; Moser, Justin D; Danner, Ronald P

    2016-09-30

    A modification of a GC was developed to investigate both infinitely dilute and finite concentrations of solvents in polymers. Thermodynamic properties of hypromellose acetate succinate (HPMCAS-L)-acetone-water systems are important for the optimization of spray-drying processes used in pharmaceutical manufacturing of solid dispersion formulations. These properties, at temperatures below the glass transition temperature, were investigated using capillary column inverse gas chromatography (CCIGC). Water was much less soluble in the HPMCAS-L than acetone. Experiments were also conducted at infinitely dilute concentrations of one of the solvents in HPMCAS-L that was already saturated with the other solvent. Overall the partitioning of the water was not significantly affected by the presence of either water or acetone in the polymer. The acetone partition coefficient decreased as either acetone or water was added to the HPMCAS-L. A representation of the HPMCAS-L structure in terms of UNIFAC groups has been developed. With these groups, the UNIFAC-vdw-FV model did a reasonable job of predicting the phase equilibria in the binary and ternary systems. The Flory-Huggins correlation with fitted interaction parameters represented the data well.

  2. Effect of malonate and p-chlorophenoxy acetic acid on hepatic succinic dehydrogenase activity of ageing lizards.

    PubMed

    Jena, B S; Patnaik, B K

    1990-01-01

    The degree of inhibition of hepatic succinic dehydrogenase activity by malonate, a competitive inhibitor, did not differ between young and middle-aged lizards. On the other hand, the same parameter increased significantly between middle-aged and old lizards. The percent inhibition of enzyme activity by p-chlorophenoxy acetic acid was also age-dependent, being higher in middle-aged and old than in young lizards.

  3. CONVERSION OF LACTATE-C14 TO PROPIONATE BY THE RUMEN MICROFLORA12

    PubMed Central

    Baldwin, R. L.; Wood, W. A.; Emery, R. S.

    1962-01-01

    Baldwin, R. L. (Michigan State University, East Lansing), W. A. Wood, and R. S. Emery. Conversion of lactate-C14 to propionate by the rumen microflora. J. Bacteriol. 83:907–913. 1962.—Rumen microflora enriched on five different diets calculated to present increasing carbohydrate or lactate availability were used to determine the contribution of the randomizing (succinate) and nonrandomizing (acrylate) routes to propionate with lactate-2-C14 and -3-C14 as substrates. Propionate was labeled as though 70 to 90% was formed via the nonrandomizing route. This percentage was highest on diets containing high levels of carbohydrate or lactate or both. Evidence for the presence of succinic dehydrogenase, acetokinase, phosphotransacetylase, and coenzyme A transphorase was obtained with cell-free extracts. Propionate-2-C14 and lactate-2-C14 were converted by extracts to the activated derivatives of acrylate, lactate, propionate, and acetate. PMID:13864343

  4. Use of acetate, propionate and butyrate for reduction of nitrate and sulfate and methanogenesis in microcosms and bioreactors simulating an oil reservoir.

    PubMed

    Chen, Chuan; Shen, Yin; An, Dongshan; Voordouw, Gerrit

    2017-01-27

    Acetate, propionate and butyrate (volatile fatty acids, VFA) occur in oil field waters and are frequently used for microbial growth of oil field consortia. We determined the kinetics of use of these VFA components (3 mM of each) by an anaerobic oil field consortium in microcosms containing 2 mM sulfate and either 0, 4, 6, 8 or 13 mM of nitrate. Nitrate was reduced first with preference for acetate and propionate. Sulfate reduction then proceeded with propionate (not butyrate) as the electron donor, whereas the fermentation of butyrate (not propionate) was associated with methanogenesis. Microbial community analyses indicated Paracoccus-Thauera, Desulfobulbus and Syntrophomonas-Methanobacterium as the dominant taxa catalyzing these three processes. Most probable number assays showed the presence of up to 10(7)/ml of propionate-oxidizing SRB in waters from the Medicine Hat Glauconitic C field. Bioreactors with the same concentrations of sulfate and VFA responded similarly to increasing concentrations of injected nitrate as observed in the microcosms: sulfide formation was prevented by adding approximately 80% of the nitrate dose needed to completely oxidize VFA to CO2 in both. Thus this work has demonstrated that simple time-dependent observations of the use of acetate, propionate and butyrate for nitrate reduction, sulfate reduction and methanogenesis in microcosms are a good proxy for these processes in bioreactors of which monitoring is more complex.

  5. Stability assessment of hypromellose acetate succinate (HPMCAS) NF for application in hot melt extrusion (HME).

    PubMed

    Sarode, Ashish L; Obara, Sakae; Tanno, Fumie K; Sandhu, Harpreet; Iyer, Raman; Shah, Navnit

    2014-01-30

    HPMCAS is a widely used polymer in the pharmaceutical industry as an excipient. In this work, the physicochemical stability of HPMCAS was investigated for hot melt extrusion (HME) application. The reduction in zero rate viscosity (η0) of the polymer with the increase in temperature was determined using rheological evaluation prior to HME processing. The energy of activation for AS-MF determined by fitting Arrhenius model to the temperature dependent reduction in η0 was found to be slightly lower than that for the other grades of HPMCAS. Glassy yellowish HMEs were obtained using Haake Mini-Lab MicroCompounder operated at 160, 180, and 200°C and 100, 200, and 300 rpm for all the grades at each temperature. Various physicochemical properties of HPMCAS such as glass transition temperature, semi-crystalline nature, solid state functional group properties, moisture content, and solution viscosity were not significantly affected by the HME processing. The most significant change was the release of acetic and succinic acid with the increase in HME temperature and speed. The free acid content release due to HME was directly proportional to the speed at lower operating temperatures. AS-LF was found to be the most stable with the lowest increase in total free acid content even at higher HME temperature and speed. Although the dissolution time was not affected due to HME for AS-LF and AS-MF grades, it was notably increased for AS-HF, perhaps due to significant reduction of succinoyl content. In conclusion, the HME processing conditions for solid dispersions of HPMCAS should be based on the acceptance levels of free acid for the drug and the drug product.

  6. Acetate, lactate, propionate, and isobutyrate as electron donors for iron and sulfate reduction in Arctic marine sediments, Svalbard.

    PubMed

    Finke, Niko; Vandieken, Verona; Jørgensen, Bo Barker

    2007-01-01

    The contribution of volatile fatty acids (VFA) as e(-)-donors for anaerobic terminal oxidation of organic carbon through iron and sulfate reduction was studied in Arctic fjord sediment. Dissolved inorganic carbon, Fe(2+), VFA concentrations, and sulfate reduction were monitored in slurries from the oxidized (0-2 cm) and the reduced (5-9 cm) zone. In the 0-2 cm layer, 2/3 of the mineralization could be attributed to sulfate reduction and 1/3 to iron reduction. In the 5-9 cm layer, sulfate reduction was the sole mineralization process. Acetate and lactate turnover rates were measured by radiotracer. Inhibition of sulfate reduction with selenate resulted in the accumulation of acetate, propionate, and isobutyrate. The acetate turnover rates determined by radiotracer and accumulation after inhibition were similar. VFA turnover accounted for 21% and 52% of the mineralization through sulfate reduction in the 0-2 and 5-9 cm layer, respectively. Acetate and lactate turnover in the inhibited 0-2 cm slurry was attributed to iron reduction and accounted for 10% and 2% of the iron reduction. Therefore, 88% and 79% of the iron and sulfate reduction in the 0-2 cm layer, respectively, must be fueled by alternative e(-)-donors. The accumulation of VFA in the selenate-inhibited 0-2 cm slurry did not enhance iron reduction, indicating that iron reducers were not limited by VFA availability.

  7. [Kinetic model of enhanced biological phosphorus removal with mixed acetic and propionic acids as carbon sources. (II): Process simulation].

    PubMed

    Zhang, Chao; Chen, Yin-Guang

    2013-03-01

    Two groups of sequencing batch reactors were used to study the metabolism substrate transformation of phosphorus-accumulating organisms (PAO) and glycogen-accumulating organisms (GAO) fed with mixed acetic and propionic acids. Seven stoichiometry parameters and 24 kinetic parameters were contained in the PAO and GAO kinetic model, and stoichiometry parameters were deduced from the stoichiometry models, while kinetic parameters were determined by experimental results. The kinetic model parameters of stoichiometry and kinetics were determined according the experiments and the literature. Subsequently, the substrate transformations of PAO and GAO were calculated by the Matlab software. The model curves matched the SBR experimental data well, indicating that the kinetic model based on SCFAs metabolism could be used to simulate PAO and GAO in anaerobic-aerobic conditions.

  8. The source of inoculum plays a defining role in the development of MEC microbial consortia fed with acetic and propionic acid mixtures.

    PubMed

    Ruiz, Vianey; Ilhan, Zehra Esra; Kang, Dae-Wook; Krajmalnik-Brown, Rosa; Buitrón, Germán

    2014-07-20

    Microbial electrolysis cells (MECs) can be used as a downstream process to dark fermentation to further capture electron in volatile fatty acids that remain after fermentation, improving this way the viability of the overall process. Acetic and propionic acid are common products of dark fermentation. The main objective of this work was to investigate the effect of different initial concentrations of a mixture of acetic and propionic acids on MECs microbial ecology and hydrogen production performance. To link microbial structure and function, we characterized the anode respiring biofilm communities using pyrosequencing and quantitative-PCR. The best hydrogen production rates (265mL/d/Lreactor) were obtained in the first block of experiments by MEC fed with 1500mg/L acetic acid and 250mg/L propionic acid. This reactor presents in the anode biofilm an even distribution of Proteobacteria, Firmicutes and Bacteroidetes and Arcobacter was the dominant genera. The above fact also correlated to the highest electron load among all the reactors. It was evidenced that although defined acetic and propionic acid concentrations fed affected the structure of the microbial consortia that developed at the anode, the initial inoculum played a major role in the development of MEC microbial consortia.

  9. Acetate favors more phosphorus accumulation into aerobic granular sludge than propionate during the treatment of synthetic fermentation liquor.

    PubMed

    Cai, Wei; Huang, Wenli; Li, Huifang; Sun, Beina; Xiao, Huasheng; Zhang, Zhenya; Lei, Zhongfang

    2016-08-01

    Anaerobic digestion (AD) is an efficient biotechnology widely applied for energy and resource recovery from organic waste and wastewater treatment. The effluent from AD or fermentation liquor containing organic substances like volatile fatty acids (VFAs) and mineral nutrients (such as N and P), however, will trigger serious environmental issues if not properly dealt with. In this study two identical sequencing batch reactors (SBRs), namely Ra and Rp were used to cultivate aerobic granules for P recovery from synthetic fermentation liquor, respectively using acetate and propionate as additional carbon source. Larger and more stable granules were achieved in Ra with higher P removal capability (9.4mgP/g-VSS·d) and higher anaerobic P release (6.9mgP/g-VSS·h). In addition to much higher P content (78mgP/g-SS), bioavailable P in Ra-granules increased to 45mgP/g-SS, approximately 2-times those of seed sludge and Rp-granules. Microbial community analysis indicated that more GAOs were accumulated in Rp-granules.

  10. Development of cellulose acetate propionate membrane for separation of ethanol and ethyl tert-butyl ether mixtures

    SciTech Connect

    Luo, G.S.; Niang, M.; Schaetzel, P.

    1997-04-01

    For pervaporation separation of ethanol and ethyl tert-butyl ether mixtures, a cellulose acetate propionate membrane was chosen as the experimental membrane because of its high selectivity and good mass fluxes. The properties of the membranes were evaluated by the pervaporation separation of mixtures of ethyl tert-butyl ether/ethanol and the sorption experiments. The experimental results showed that the selectivity and the permeates depend on the ethanol concentration in the feed and the experimental temperature. With increases of the ethanol weight fraction in the feed and the temperature, the total and partial mass fluxes increased. With respect to the temperature, ethanol mass flux obeys the Arrhenius equation. The selectivity of this membrane decreases as the temperature and the ethanol concentration in the feed increase. This membrane shows special characteristics at the azeotropic composition. In the vicinity of the azeotropic point, minimum values of ethanol concentration in the permeate and in sorption solution are obtained. The swelling ratios increase when temperature and the ethanol concentration in the feed are increasing. The ethanol concentration in the sorption solution is also influenced by the temperature and the mixture`s composition. When the temperature increases, the sorption selectivity of the membrane decreases.

  11. Dynamics of three organic acids (malic, acetic and succinic acid) in sunflower exposed to cadmium and lead.

    PubMed

    Niu, Zhixin; Li, Xiaodong; Sun, Lina; Sun, Tieheng

    2013-01-01

    Sunflower (Helianthus annuus L.) has been considered as a good candidate for bioaccumulation of heavy metals. In the present study, sunflower was used to enrich the cadmium and lead in sand culture during 90 days. Biomass, Cd and Pb uptake, three organic acids and pH in cultures were investigated. Results showed that the existence of Cd and Pb showed different interactions on the organic acids exudation. In single Cd treatments, malic and acetic acids in Cd10 showed an incremental tendency with time. In the mixed treatments of Cd and Pb, malic acids increased when 10 and 40 mg x L(-1) Cd were added into Pb50, but acetic acids in Pb50 were inhibited by Cd addition. The Cd10 supplied in Pb10 stimulated the secretion of malic and succinic acids. Moreover, the Cd or Pb uptake in sunflower showed various correlations with pH and some organic acids, which might be due to the fact that the Cd and Pb interfere with the organic acids secretion in rhizosphere of sunflower, and the changes of organic acids altered the form and bioavailability of Cd and Pb in cultures conversely.

  12. The voluntary intake of hay and silage by lactating cows in response to ruminal infusion of acetate or propionate, or both, with or without distension of the rumen by a balloon.

    PubMed

    Mbanya, J N; Anil, M H; Forbes, J M

    1993-05-01

    In order to test the hypothesis that negative feedback signals from abdominal receptors are integrated in an additive manner in the control of voluntary food intake, cows with rumen fistulas were given intraruminal infusions of sodium acetate or sodium propionate, or both, with or without distension of the rumen by balloon. Intakes were monitored during the 3 h experimental period and for 2 h after and samples of rumen fluid were taken for estimation of short-chain fatty acid concentrations and osmolality. Six cows in mid-lactation were fed on hay and concentrates and given, into the rumen, 5.5 mol sodium acetate, 5.2 mol sodium propionate and 7.5 l of distension. Compared with the control (water infusion), neither acetate, propionate nor distension significantly depressed hay intake when given separately. When given in combination, however, the following significantly depressed intake during the 3 h treatment period: propionate + distension, acetate + distension, acetate + propionate + distension. Seven cows in early lactation were fed on silage and concentrates and given, into the rumen, 9.0 mol sodium acetate, 4.0 mol sodium propionate and 10.0 litres of distension. Again, none of the three given alone depressed silage intake to a significant extent during the 3 h treatment period, whereas the following combinations had a significant effect: propionate + distension, acetate + distension, acetate + propionate + distension. Basal rumen osmolalities were similar for the two types of feed but infusion of the sodium salts caused a very much greater increase with silage than with hay.(ABSTRACT TRUNCATED AT 250 WORDS)

  13. Concomitant changes in progesterone catabolic enzymes, cytochrome P450 2C and 3A, with plasma insulin concentrations in ewes supplemented with sodium acetate or sodium propionate.

    PubMed

    Lemley, C O; Koch, J M; Blemings, K P; Krause, K M; Wilson, M E

    2008-08-01

    Progesterone is essential for maintaining pregnancy, and several authors have suggested that low peripheral concentrations of progesterone may be responsible for high rates of embryonic loss. The primary organ involved in the catabolism of progesterone is the liver, and cytochrome P450 2C and 3A sub-families account for a large proportion of this catabolism. Elucidating a mechanism to decrease progesterone catabolism, thereby increasing embryonic and uterine exposure to progesterone, seems a logical approach to ameliorate high rates of embryonic loss. The objectives of the current experiment were to determine the pattern of insulin secretion after supplementing feed with either sodium acetate or sodium propionate and to determine any association between the differential patterns of insulin secretion with the hepatic activity of cytochrome P450 2C and 3A and progesterone clearance. Sixteen ovariectomized ewes were fed 3 kg/day for 10 days of a diet consisting of 50% corn silage, 38% triticale haylage, 12% soybean meal and 600 ml of 3.5 M sodium acetate (energy control; n = 8) or 2.0 M sodium propionate (gluconeogenic substrate; n = 8). Equal portions of the ration (1 kg as-fed basis along with 200 ml of 3.5 M sodium acetate or 2.0 M sodium propionate) were offered three times daily at 0600, 1400 and 2200 h. Concentrations of insulin in plasma were determined immediately before feeding and at 15, 30, 60, 90, 120, 180, 240 and 300 min after feeding. Progesterone clearance from peripheral circulation (ng/ml per min) was measured by giving a 5 mg injection of progesterone into the left jugular vein and collecting blood via the right jugular vein at 0, 2, 4, 6, 8, 10, 15, 20 and 30 min afterwards. Liver biopsies were taken 1 h after feeding to determine cytochrome P450 2C and 3A activities. Insulin concentrations in ewes supplemented with sodium propionate were elevated at 15, 30 and 60 min after feeding compared to the sodium acetate group. Cytochrome P450 2C and 3A

  14. Minimal inhibitory concentrations of undissociated lactic, acetic, citric and propionic acid for Listeria monocytogenes under conditions relevant to cheese.

    PubMed

    Wemmenhove, Ellen; van Valenberg, Hein J F; Zwietering, Marcel H; van Hooijdonk, Toon C M; Wells-Bennik, Marjon H J

    2016-09-01

    Minimal inhibitory concentrations (MICs) of undissociated lactic acid were determined for six different Listeria monocytogenes strains at 30 °C and in a pH range of 4.2-5.8. Small increments in pH and acid concentrations were used to accurately establish the growth/no growth limits of L. monocytogenes for these acids. The MICs of undissociated lactic acid in the pH range of 5.2-5.8 were generally higher than at pH 4.6 for the different L. monocytogenes strains. The average MIC of undissociated lactic acid was 5.0 (SD 1.5) mM in the pH range 5.2-5.6, which is relevant to Gouda cheese. Significant differences in MICs of undissociated lactic acid were found between strains of L. monocytogenes at a given pH, with a maximum observed level of 9.0 mM. Variations in MICs were mostly due to strain variation. In the pH range 5.2-5.6, the MICs of undissociated lactic acid were not significantly different at 12 °C and 30 °C. The average MICs of undissociated acetic acid, citric acid, and propionic acid were 19.0 (SD 6.5) mM, 3.8 (SD 0.9) mM, and 11.0 (SD 6.3) mM, respectively, for the six L. monocytogenes strains tested in the pH range 5.2-5.6. Variations in MICs of these organic acids for L. monocytogenes were also mostly due to strain variation. The generated data contribute to improved predictions of growth/no growth of L. monocytogenes in cheese and other foods containing these organic acids.

  15. Factors influencing rumen fermentation: effect of hydrogen on formation of propionate.

    PubMed

    Schulman, M D; Valentino, D

    1976-08-01

    The effect of hydrogen on fermentation of lactate, pyruvate, fumarate, and succinate by resting rumen microorganisms has been investigated. Under an atmosphere of nitrogen, lactate was fermented to yield acetate as the major product (85 to 100 mole %) and propionate (0 to 17 mole %) and butyrate (0 to 3%) as secondary products. Under hydrogen, there was increased formation of both propionate and total volatile fatty acids. The amount of propionate increased 4 to 8 times and total volatile fatty acids 2.5 to 3.2 times. Propionate formation was proportional to the hydrogen concentration and reached a maximum at a partial pressure of hydrogen of .2 N/m2. With [2-carbon-14] lactate, propionate was formed via the dicarboxylic acid pathway under both nitrogen or hydrogen. Hydrogen did not affect significantly the fermentation of pyruvate or succinate. With fumarate under hydrogen, propionate and total volatile fatty acids increased 6.8 and 2 times while acetate was unchanged. The mechanism by which hydrogen exerts these effects is discussed in relation to the role of methanogenesis in the rumen.

  16. Effects of injection of acetic acid and propionic acid for total phosphorus removal at high temperature in enhanced biological phosphorus removal process.

    PubMed

    Ki, C Y; Kwon, K H; Kim, S W; Min, K S; Lee, T U; Park, D J

    2014-01-01

    In summer, wastewater treatment plant total phosphorus (TP) removal efficiency is low in South Korea. The reason is because of high temperatures or significant fluctuation of inflow characteristics caused by frequent rainfall. Hence, this study tried to raise TP removal efficiency by injecting fixed external carbon sources in real sewage. Polyphosphate accumulating organisms (PAOs) and glycogen accumulating organisms (GAOs) compete to occupy microorganisms at high temperature. Propionate is known to restrain GAOs. Thus, acetate and propionate were chosen as the external carbon source in this study to find out the suitable volume and ratio of carbon source which ensured the dominance of PAOs. An external carbon source was supplied in the anaerobic reactor of the biological phosphorus removal process at high temperature (above 25 °C). TP removal efficiency was improved by injecting an external carbon source compared to that without an external carbon source. Also, it remained relatively stable when injecting an external carbon source, despite the variation in temperature. TP removal efficiency was the highest when injecting acetate and propionate in the proportion of 2:1 (total concentration as chemical oxygen demand (COD) is 12 mg/L in influent).

  17. Sensitivity of acid-adapted and acid-shocked Shigella flexneri to reduced pH achieved with acetic, lactic, and propionic acids.

    PubMed

    Tetteh, G L; Beuchat, L R

    2001-07-01

    Survival and growth characteristics of unadapted, acid-adapted, and acid-shocked Shigella flexneri 2a cells in acidified (pH 3.5 to 5.5) tryptic soy broth with 0.25% glucose (TSB) and tryptic soy agar (TSA) were determined. S. flexneri was grown at 37 degrees C for 18 h in tryptic soy broth without glucose (TSBNG) (unadapted) and TSBNG supplemented with 1% glucose (TSBG) (acid-adapted). Cells grown in TSBNG were acid shocked by adjusting 16-h cultures to pH 5.05 +/- 0.05 with lactic acid. Cells were then inoculated into TSB acidified with acetic, lactic, or propionic acids to pH 5.5, 4.5, or 3.5 and incubated at 37 degrees C for 6 h. The order of lethality at a given pH was lactic acid < acetic acid < propionic acid. Significantly (P < or = 0.05) higher numbers of acid-adapted cells, compared to acid-shocked and unadapted cells, were recovered from TSB acidified (pH 3.5) with lactic or acetic acids. None of the cells survived a 30-min exposure in TSB acidified with propionic acid to pH 3.5. When the three cell types were plated on TSA acidified with lactic, acetic, or propionic acids at pH < or = 4.5, < or = 5.5, and < or = 5.5, respectively, visible colonies were not detected. Viable unadapted, acid-adapted, and acid-shocked cells were, however, recovered from TSA acidified with all three acids at pH > or = 4.5. Acid-adapted and, to a lesser extent, acid-shocked cells survived at lower pH than did unadapted cells, indicating that prior exposure to mild acidic environment results in increased acid resistance. Survival of S. flexneri at a given pH was influenced by the type of acidulant used, a response characteristic exhibited by other gram-negative enteric pathogens.

  18. Extractive fermentation for enhanced propionic acid production from lactose by Propionibacterium acidipropionici

    SciTech Connect

    Jin, Z.; Yang, S.T.

    1998-05-01

    An extractive fermentation process using an amine extractant and a hollow-fiber membrane extractor to selectively remove propionic acid from the fermentation broth was developed to produce propionate from lactose. Compared to the conventional batch fermentation, the extractive fermentation had a much higher productivity ({approximately}1 g/(L{center_dot}h) or 5-fold increase), higher propionate yield (up to 0.66 g/g or more than 20% increase), higher final product concentration (75 g/L or higher), and higher product purity ({approximately}90%). Meanwhile, acetate and succinate productions in the extractive fermentation were significantly reduced. The improved fermentation performance can be attributed to the reduced product inhibition and a possible metabolic pathway shift to favor more propionic but less acetic and succinic acid production. The process was stable and gave consistent long-term performance over the 1.5-month period studied. The effects of propionate concentration, pH, and amine content in the solvent on the extractive fermentation were also studied and are discussed in this paper.

  19. Inhibitory effect of hydroxypropyl methylcellulose acetate succinate on drug recrystallization from a supersaturated solution assessed using nuclear magnetic resonance measurements.

    PubMed

    Ueda, Keisuke; Higashi, Kenjirou; Yamamoto, Keiji; Moribe, Kunikazu

    2013-10-07

    We examined the inhibitory effect of hydroxypropyl methylcellulose acetate succinate (HPMC-AS) on drug recrystallization from a supersaturated solution using carbamazepine (CBZ) and phenytoin (PHT) as model drugs. HPMC-AS HF grade (HF) inhibited the recrystallization of CBZ more strongly than that by HPMC-AS LF grade (LF). 1D-1H NMR measurements showed that the molecular mobility of CBZ was clearly suppressed in the HF solution compared to that in the LF solution. Interaction between CBZ and HF in a supersaturated solution was directly detected using nuclear Overhauser effect spectroscopy (NOESY). The cross-peak intensity obtained using NOESY of HF protons with CBZ aromatic protons was greater than that with the amide proton, which indicated that CBZ had hydrophobic interactions with HF in a supersaturated solution. In contrast, no interaction was observed between CBZ and LF in the LF solution. Saturation transfer difference NMR measurement was used to determine the interaction sites between CBZ and HF. Strong interaction with CBZ was observed with the acetyl substituent of HPMC-AS although the interaction with the succinoyl substituent was quite small. The acetyl groups played an important role in the hydrophobic interaction between HF and CBZ. In addition, HF appeared to be more hydrophobic than LF because of the smaller ratio of the succinoyl substituent. This might be responsible for the strong hydrophobic interaction between HF and CBZ. The intermolecular interactions between CBZ and HPMC-AS shown by using NMR spectroscopy clearly explained the strength of inhibition of HPMC-AS on drug recrystallization.

  20. Effect of guanidino-propionic acid on lymphocyte proliferation.

    PubMed

    Shainkin-Kestenbaum, R; Winikoff, Y; Dvilansky, A; Chaimovitz, C; Nathan, I

    1986-01-01

    The 'uremic toxin', guanidino propionic acid (GPA), which was detected in uremic serum in correlation with BUN level, modified the mitogenic response of normal lymphocytes to phytohemagglutinin (PHA). Mild modifications can be detected in the concentrations which are found in uremic patients. Other guanidino compounds which have been detected in uremic sera, such as guanidino succinic acid (GSA), guanidino butyric acid (GBA) and guanidino acetic acid (GAA), show similar inhibitory pathways. It is suggested that guanidino compounds contribute to the immunological disturbances in uremia. The complexity of their action on lymphocyte mitogenic response is probably the cause of the conflicting results which have been reported in the literature.

  1. Wheat flour based propionic acid fermentation: an economic approach.

    PubMed

    Kagliwal, Lalit D; Survase, Shrikant A; Singhal, Rekha S; Granström, Tom

    2013-02-01

    A process for the fermentative production of propionic acid from whole wheat flour using starch and gluten as nutrients is presented. Hydrolysis of wheat flour starch using amylases was optimized. A batch fermentation of hydrolysate supplemented with various nitrogen sources using Propionibacterium acidipropionici NRRL B 3569 was performed. The maximum production of 48.61, 9.40, and 11.06 g of propionic acid, acetic acid and succinic acid, respectively, was found with wheat flour hydrolysate equivalent to 90 g/l glucose and supplemented with 15 g/l yeast extract. Further, replacement of yeast extract with wheat gluten hydrolysate showed utilization of gluten hydrolysate without compromising the yields and also improving the economics of the process. The process so developed could be useful for production of animal feed from whole wheat with in situ production of preservatives, and also suggest utilization of sprouted or germinated wheat for the production of organic acids.

  2. Metabolism of Propane, n-Propylamine, and Propionate by Hydrocarbon-Utilizing Bacteria1

    PubMed Central

    Blevins, W. T.; Perry, J. J.

    1972-01-01

    Studies were conducted on the oxidation and assimilation of various three-carbon compounds by a gram-positive rod isolated from soil and designated strain R-22. This organism can utilize propane, propionate, or n-propylamine as sole source of carbon and energy. Respiration rates, enzyme assays, and 14CO2 incorporation experiments suggest that propane is metabolized via methyl ketone formation; propionate and n-propylamine are metabolized via the methylmalonyl-succinate pathway. Isocitrate lyase activity was found in cells grown on acetate and was not present in cells grown on propionate or n-propylamine. 14CO2 was incorporated into pyruvate when propionate and n-propylamine were oxidized in the presence of NaAsO2, but insignificant radioactivity was found in pyruvate produced during the oxidation of propane and acetone. The n-propylamine dissimilatory mechanism was inducible in strain R-22, and amine dehydrogenase activity was detected in cells grown on n-propylamine. Radiorespirometer and 14CO2 incorporation studies with several propane-utilizing organisms indicate that the methylmalonyl-succinate pathway is the predominant one for the metabolism of propionate. PMID:16559164

  3. ATP Synthesis-coupled and -uncoupled Acetate Production from Acetyl-CoA by Mitochondrial Acetate:Succinate CoA-transferase and Acetyl-CoA Thioesterase in Trypanosoma*

    PubMed Central

    Millerioux, Yoann; Morand, Pauline; Biran, Marc; Mazet, Muriel; Moreau, Patrick; Wargnies, Marion; Ebikeme, Charles; Deramchia, Kamel; Gales, Lara; Portais, Jean-Charles; Boshart, Michael; Franconi, Jean-Michel; Bringaud, Frédéric

    2012-01-01

    Insect stage trypanosomes use an “acetate shuttle” to transfer mitochondrial acetyl-CoA to the cytosol for the essential fatty acid biosynthesis. The mitochondrial acetate sources are acetate:succinate CoA-transferase (ASCT) and an unknown enzymatic activity. We have identified a gene encoding acetyl-CoA thioesterase (ACH) activity, which is shown to be the second acetate source. First, RNAi-mediated repression of ASCT in the ACH null background abolishes acetate production from glucose, as opposed to both single ASCT and ACH mutants. Second, incorporation of radiolabeled glucose into fatty acids is also abolished in this ACH/ASCT double mutant. ASCT is involved in ATP production, whereas ACH is not, because the ASCT null mutant is ∼1000 times more sensitive to oligomycin, a specific inhibitor of the mitochondrial F0/F1-ATP synthase, than wild-type cells or the ACH null mutant. This was confirmed by RNAi repression of the F0/F1-ATP synthase F1β subunit, which is lethal when performed in the ASCT null background but not in the wild-type cells or the ACH null background. We concluded that acetate is produced from both ASCT and ACH; however, only ASCT is responsible, together with the F0/F1-ATP synthase, for ATP production in the mitochondrion. PMID:22474284

  4. Whey fermentation by anaerobiospirillum succiniciproducens for production of a succinate-based animal feed additive

    PubMed

    Samuelov; Datta; Jain; Zeikus

    1999-05-01

    Anaerobic fermentation processes for the production of a succinate-rich animal feed supplement from raw whey were investigated with batch, continuous, and variable-volume fed-batch cultures with Anaerobiospirillum succiniciproducens. The highest succinate yield, 90%, was obtained in a variable-volume fed-batch process in comparison to 80% yield in a batch cultivation mode. In continuous culture, succinate productivity was 3 g/liter/h, and the yield was 60%. Under conditions of excess CO2, more than 90% of the whey-lactose was consumed, with an end product ratio of 4 succinate to 1 acetate. Under conditions of limited CO2, lactose was only partially consumed and lactate was the major end product, with lower levels of ethanol, succinate, and acetate. When the succinic acid in this fermentation product was added to rumen fluid, it was completely consumed by a mixed rumen population and was 90% decarboxylated to propionate on a molar basis. The whey fermentation product formed under excess CO2, which contained mainly organic acids and cells, could potentially be used as an animal feed supplement.

  5. Whey fermentation by Anaerobiospirillum succiniciproducens for production of a succinate-based animal feed additive

    SciTech Connect

    Samuelov, N.S.; Datta, R.; Jain, M.K. |; Zeikus, J.G. |

    1999-05-01

    Anaerobic fermentation processes for the production of a succinate-rich animal feed supplement from raw whey were investigated with batch, continuous, and variable-volume fed-batch cultures with Anaerobiospirillum succiniciproducens. The highest succinate yield, 90%, was obtained in a variable-volume fed-batch process in comparison to 80% yield in a batch cultivation mode. In continuous culture, succinate productivity was 3 g/liter/h, and the yield was 60%. Under conditions of excess CO{sub 2}, more than 90% of the whey-lactose was consumed, with an end product ratio of 4 succinate to 1 acetate. Under conditions of limited CO{sub 2}, lactose was only partially consumed and lactate was the major end product, with lower levels of ethanol, succinate, and acetate. When the succinic acid in this fermentation product was added to rumen fluid, it was completely consumed by a mixed rumen population and was 90% decarboxylated to propionate on a molar basis. The whey fermentation product formed under excess CO{sub 2}, which contained mainly organic acids and cells, could potentially be used as an animal feed supplement.

  6. A direct pathway for the conversion of propionate into pyruvate in Moraxella lwoffi

    PubMed Central

    Hodgson, B.; McGarry, J. D.

    1968-01-01

    1. The identity of the organism previously known as Vibrio O1 (N.C.I.B. 8250) with a species of Moraxella is established. 2. The ability of cells to oxidize propionate is present only in cells with an endogenous respiration and this ability is increased 80-fold when the organism is grown with propionate. 3. Isocitrate lyase activity in extracts from propionate-grown cells is the same as that in extracts from lactate-grown cells, about tenfold greater than that in extracts from succinate-grown cells and slightly greater than half the activity in extracts from acetate-grown cells. 4. With arsenite as an inhibitor conditions were found in which the organism would catalyse the quantitative oxidation of propionate to pyruvate. When propionate was completely utilized pyruvate was metabolized further to 2-oxoglutarate. 5. The oxidation of propionate by cells was incomplete both in a `closed system' with alkali to trap respiratory carbon dioxide and in an `open system' with an atmosphere of oxygen+carbon dioxide (95:5). Acetate accumulated. Under these conditions [2-14C]- and [3-14C]-propionate gave rise to [14C]acetate. The rate of conversion of [2-14C]propionate into 14CO2, although much less than the rate of conversion of [1-14C]propionate into 14CO2, was slightly greater than the rate of conversion of [3-14C]propionate into 14CO2. 6. The oxidation of propionate by cells was complete in an `open system' with an atmosphere of either oxygen or air. Under these conditions very little [1-14C]propionate was converted into 14C-labelled cell material. The conversion of [2-14C]- and [3-14C]-propionate into 14C-labelled cell material occurred at an appreciable rate, the rate for the incorporation of [3-14C]propionate being slightly more rapid. In the absence of a utilizable nitrogen source part of the [14C]propionate was incorporated into some reserve material, which was oxidized when added substrate had been completely utilized. 7. [14C]-Pyruvate produced from [14C]propionate

  7. Divergent Metabolic Pathways for Propane and Propionate Utilization by a Soil Isolate1

    PubMed Central

    Vestal, J. R.; Perry, Jerome J.

    1969-01-01

    The metabolism of propane and propionate by a soil isolate (Brevibacterium sp. strain JOB5) was investigated. The presence of isocitrate lyase in cells grown on isopropanol, acetate, or propane and the absence of this inducible enzyme in n-propanol- and propionate-grown cells suggested that propane is not metabolized via C-terminal oxidation. Methylmalonyl coenzyme A mutase and malate synthase are constitutive in this organism. The incorporation of 14CO2 into pyruvate accumulated during propionate utilization suggests that propionate is metabolized via the methyl-malonyl-succinate pathway. These results were further substantiated by radiorespirometric studies with propionate-1-14C, -2-14C, and -3-14C as substrate. Propane -2-14C was shown, by unlabeled competitor experiments, to be oxidized to acetone; acetone and isopropanol are oxidized in this organism to acetol. Cleavage of acetol to acetate and CO2 would yield the inducer for the isocitrate lyase present in propane-grown cells. PMID:5802607

  8. Eubacterium pyruvativorans sp. nov., a novel non-saccharolytic anaerobe from the rumen that ferments pyruvate and amino acids, forms caproate and utilizes acetate and propionate.

    PubMed

    Wallace, R J; McKain, N; McEwan, N R; Miyagawa, E; Chaudhary, L C; King, T P; Walker, N D; Apajalahti, J H A; Newbold, C J

    2003-07-01

    Two similar gram-positive rods were isolated from 10(-6) dilutions of ruminal fluid from a sheep receiving a mixed grass hay/concentrate diet, using a medium containing pancreatic casein hydrolysate as sole source of carbon and energy. The isolates did not ferment sugars, but grew on pyruvate or trypticase, forming caproate as the main fermentation product and valerate to a lesser extent. Acetate and propionate were utilized. One of these strains, I-6T, was selected for further study. Strain I-6T was a non-motile coccal rod, 1.2 x 0.4 microm, with a gram-positive cell wall ultrastructure and a G + C content of 56.8 mol%. No spores were visible, and strain I-6T did not survive heating at 80 degrees C for 10 min. Its rate of NH3 production was 375 nmol (mg protein)(-1) min(-1), placing it in the 'ammonia-hyperproducing' (or HAP) group of ruminal bacteria. 16S rDNA sequence analysis (1296 bases) indicated that it represents a novel species within the 'low-G + C' gram-positive group, for which the name Eubacterium pyruvativorans sp. nov. is proposed. Among cultivated bacteria, strain I-6T was most closely related (89% identity) to other asaccharolytic Eubacterium isolates from the mouth and the rumen. It was 98% identical to uncultured bacterial sequences amplified by others from ruminal digesta.

  9. The long-term effect of initial pH control on the enrichment culture of phosphorus- and glycogen-accumulating organisms with a mixture of propionic and acetic acids as carbon sources.

    PubMed

    Zhang, Chao; Chen, Yinguang; Liu, Yan

    2007-11-01

    In most studies on phosphorus- and glycogen-accumulating organisms (PAO and GAO), pH was controlled constantly throughout the entire anaerobic and aerobic periods, and acetic acid was used as the carbon source. In this paper, the effect of long-term initial pH values on PAO and GAO was investigated with mixed propionic and acetic acids as carbon sources. It was observed that with pH increasing from 6.4 to 8.0, the anaerobic propionic acid uptake rate by PAO linearly increased but that by GAO proportionally decreased. At pH 6.70 and pH 7.51, PAO and GAO exhibited the same acetic and propionic acid uptake rates, respectively. The acetic acid uptake rate by PAO was greater than that by GAO at pH>6.70, and the propionic acid uptake rate by PAO was higher than that by GAO at pH>7.51, which indicated that PAO would take predominance over GAO at pH>7.51. Poly-3-hydroxybutyrate, poly-3-hydroxyvalerate and poly-3-hydroxy-2-methylvalerate shared 7%, 62% and 31%, respectively in the PAO system, and 11%, 44% and 45% respectively in the GAO system, and these fractions were observed independent of pH either in the PAO or in the GAO system. In the PAO system, with the increase of pH, the phosphorus removal efficiency was improved greatly, and a phosphorus removal efficiency of 100% was achieved at 8.0. Further investigation showed that the higher phosphorus removal efficiency at higher pH was mainly caused by a biological effect instead of chemical one.

  10. Site-specific drug delivery to the middle region of the small intestine by application of enteric coating with hypromellose acetate succinate (HPMCAS).

    PubMed

    Tanno, Fumié K; Sakuma, Shinji; Masaoka, Yoshie; Kataoka, Makoto; Kozaki, Toshio; Kamaguchi, Ryosei; Ikeda, Yutaka; Kokubo, Hiroyasu; Yamashita, Shinji

    2008-07-01

    Enteric coatings that deliver drugs to specific regions of the small intestine were examined. Hypromellose acetate succinate (HPMCAS) with different values of succinoyl group contents was used. Decreasing the succinoyl group content resulted in an increase in the pH at which HPMCAS started to dissolve. Drug-containing granules with or without enteric coating were prepared and their in vitro dissolution in a simulated intestinal fluid of pH 6.8 was examined. Granules coated with HPMCAS having the succinoyl group content of 6.2% showed a lag time of about 30 min, although drug release from granules without coating was completed within 20 min. The time lag and dissolution rate were extended and reduced, respectively, as the succinoyl group content was decreased. Rat experiments indicated that enteric-coated granules disintegrated and the bulk of the drugs was immediately released when the granules reached a specific site of the small intestine where the pH corresponded to the pH at which the enteric coating agent started to dissolve. Similar results were observed in monkey experiments. It was suggested that HPMCAS with the succinoyl group content of about 5% was suitable as an enteric coating agent for delivering drugs to the middle-to-lower region of the small intestine.

  11. Preparation and Evaluation of Diclofenac Sodium Tablet Coated with Polyelectrolyte Multilayer Film Using Hypromellose Acetate Succinate and Polymethacrylates for pH-Dependent, Modified Release Drug Delivery.

    PubMed

    Jeganathan, Balamurugan; Prakya, Vijayalakshmi; Deshmukh, Abhijit

    2016-06-01

    Polyelectrolyte multilayer (PEM) film formed due to the electrostatic interaction between oppositely charged polyelectrolytes is of considerable interest because of their potential applications as both drug carriers and surface-modifying agents. In this study, in vitro studies were carried out on polyelectrolyte complexes formulated with Eudragit E (EE) and hypromellose acetate succinate (HPMCAS). The complexes of EE and HPMCAS were formulated by non-stoichiometric method. The prepared IPCs were investigated using Fourier transform infrared spectroscopy. Diclofenac sodium (DS) tablets were prepared and were coated with polymer solution of HPMCAS and EE to achieve pH-dependent and sustained-release tablets. Tablets were evaluated for their physical characteristics and in vitro drug release. The results of pharmacokinetic studies in rabbits showed that the selected formulation (F6) exhibited a delayed peak plasma concentration and marked sustained-release effect of drug in the in vivo drug release in comparison with marketed tablet. The suitable combination of PEM film based on EE and HPMCAS demonstrated potential candidate for targeted release of DS in the lower part of the gastrointestinal (GI) tract.

  12. Interpolyelectrolyte complexes of Eudragit® EPO with hypromellose acetate succinate and Eudragit® EPO with hypromellose phthalate as potential carriers for oral controlled drug delivery.

    PubMed

    Jeganathan, Balamurugan; Prakya, Vijayalakshmi

    2015-08-01

    The objective of this study was to compare a novel controlled release tablet formulation based on interpolyelectrolyte complex (PEC). Interpolymer interactions between the countercharged polymers like Eudragit® EPO (polycation) and hypromellose acetate succinate (polyanion) and Eudragit® EPO and hypromellose phthalate (polyanion) were investigated with a view to their use in per oral controlled release drug delivery systems. The formation of inter-macromolecular ionic bonds between cationic polymer and anionic polymer was investigated using Fourier transform infrared (FT-IR) spectroscopy and differential scanning calorimetry. The FT-IR spectra of the tested polymeric matrices are characterized by visible changes in the observed IR region indicating the interaction between chains of two oppositely charged copolymers. The performance of the in situ formed PEC as a matrix for controlled release of drugs was evaluated, using acetaminophen as a model drug. The dissolution data of these matrices were fitted to different dissolution models. It was found that drug release followed zero-order kinetics and was controlled by the superposition of the diffusion and erosion. These profiles could be controlled by conveniently modifying the proportion of the polymer ratio, polymer type, and polymer concentration the in the tablets.

  13. Absolute molecular weight determination of hypromellose acetate succinate by size exclusion chromatography: use of a multi angle laser light scattering detector and a mixed solvent.

    PubMed

    Chen, Raymond; Ilasi, Nicholas; Sekulic, Sonja S

    2011-12-05

    Molecular weight distribution is an important quality attribute for hypromellose acetate succinate (HPMCAS), a pharmaceutical excipient used in spray-dried dispersions. Our previous study showed that neither relative nor universal calibration method of size exclusion chromatography (SEC) works for HPMCAS polymers. We here report our effort to develop a SEC method using a mass sensitive multi angle laser light scattering detector (MALLS) to determine molecular weight distributions of HPMCAS polymers. A solvent screen study reveals that a mixed solvent (60:40%, v/v 50mM NaH(2)PO(4) with 0.1M NaNO(3) buffer: acetonitrile, pH* 8.0) is the best for HPMCAS-LF and MF sub-classes. Use of a mixed solvent creates a challenging condition for the method that uses refractive index detector. Therefore, we thoroughly evaluated the method performance and robustness. The mean weight average molecular weight of a polyethylene oxide standard has a 95% confidence interval of (28,443-28,793) g/mol vs. 28,700g/mol from the Certificate of Analysis. The relative standard deviations of average molecular weights for all polymers are 3-6%. These results and the Design of Experiments study demonstrate that the method is accurate and robust.

  14. Comparison of zinc acetate and propionate addition on gastrointestinal tract fermentation and susceptibility of laying hens to Salmonella enteritidis during forced molt.

    PubMed

    Moore, R W; Park, S Y; Kubena, L F; Byrd, J A; McReynolds, J L; Burnham, M R; Hume, M E; Birkhold, S G; Nisbet, D J; Ricke, S C

    2004-08-01

    Feed deprivation is the most common method used to induce molting and stimulate multiple egg-laying cycles in laying hens for commercial egg production. Unfortunately, an increased risk of Salmonella enteritidis (SE) colonization may result from the use of this method. Methods to stimulate multiple egg-laying cycles without increasing the risk of SE are needed. In each of 3 experiments, hens over 50 wk of age were divided into groups of 12 and placed in individual laying cages. One week before dietary changes, hens were put on an 8L:16D photoperiod that continued for the 9-d experimental period. Hens in all treatments were challenged orally with 10(4) cfu of SE on the fourth day. Treatments were full fed hens (nonmolted, NM), nonfed hens (molted, M), a zinc acetate diet (ZAC), and a zinc propionate diet (ZPR). The zinc diets contained 10,000 mg of zinc per kilogram of diet. Body weight losses were significantly higher in the M, ZPR, and ZAC treatments than in the NM treatment. Crop lactic acid decreased more in M, ZPR, and ZAC treatments than in NM hens in trial 2. Crop pH was significantly (P < 0.05) lower in NM hens than in M, ZAC, and ZPR hens in trial 2. Although cecal individual or total volatile fatty acids (VFA), and lactic acid were not significantly (P > 0.05) different between NM hens and M, ZAC and ZPR hens in trial 1, lactic acid was significantly (P < 0.05) higher in NM hens than in M, ZAC and ZPR hens (trial 2), and cecal total VFA were lower in M hens than in NM, ZAC and ZPR hens (trial 3). Colonization of SE in the crop and ceca was higher in the M and ZPR hens (trials 1 and 2). Liver, spleen, or ovary invasion by SE was higher in the M and ZPR hens (trials 1 and 2) than in NM hens. At the zinc concentration used in these studies, the zinc dietary regimens may be effective for reducing the risk of SE during induced molt.

  15. An economical biorefinery process for propionic acid production from glycerol and potato juice using high cell density fermentation.

    PubMed

    Dishisha, Tarek; Ståhl, Åke; Lundmark, Stefan; Hatti-Kaul, Rajni

    2013-05-01

    An economically sustainable process was developed for propionic acid production by fermentation of glycerol using Propionibacterium acidipropionici and potato juice, a by-product of starch processing, as a nitrogen/vitamin source. The fermentation was done as high-cell-density sequential batches with cell recycle. Propionic acid production and glycerol consumption rates were dependent on initial biomass concentration, and reached a maximum of 1.42 and 2.30 g L(-1) h(-1), respectively, from 50 g L(-1) glycerol at initial cell density of 23.7 gCDW L(-1). Halving the concentration of nitrogen/vitamin source resulted in reduction of acetic and succinic acids yields by ~39% each. At glycerol concentrations of 85 and 120 g L(-1), respectively, 43.8 and 50.8 g L(-1) propionic acid were obtained at a rate of 0.88 and 0.29 g L(-1) h(-1) and yield of 84 and 78 mol%. Succinic acid was 13 g% of propionic acid and could represent a potential co-product covering the cost of nitrogen/vitamin source.

  16. Simultaneous determination of 4-hydroxyphenyl lactic acid, 4-hydroxyphenyl acetic acid, and 3-4-hydroxyphenyl propionic acid in human urine by Ultra high performance liquid chromatography with fluorescence detection.

    PubMed

    Yang, Yongli; Liu, Fan; Wan, Yiqun

    2017-03-27

    A simple and reliable method was established for simultaneous determination of 4-hydroxyphenyl acetic acid, 4-hydroxyphenyl lactic acid, and 3-4-hydroxyphenyl propionic acid in human urine by high-performance liquid chromatography with fluorescence detection. Solid-phase extraction was used to eliminate the interferences in urine. The separation of three analytes was achieved using a C18 column and a mobile phase formed by a 95:5 v/v mixture of 50 mmol/L ammonium acetate buffer at pH 6.8 that contained 5 mmol/L tetrabutyl ammonium bromide and acetonitrile. Under the optimized conditions, the detection limits of 4-hydroxyphenyl acetic acid, 4-hydroxyphenyl lactic acid, and 3-4-hydroxyphenyl propionic acid were 4.8 × 10(-3) , 8.80 × 10(-3) , and 9.00 × 10(-3) mg/L, respectively, and the recoveries were in the range of 85.0-120.0% with relative standard deviations of 1.5-3.1%. This method was used to analyze urine samples from breast cancer patients, healthy people and postsurgery breast cancer patients. Significant differences of urinary levels of 4-hydroxyphenyl acetic acid and 4-hydroxyphenyl lactic acid could be found between the breast cancer patients group and other two groups. No effect of age and sex was observed on the urinary levels of 4-hydroxyphenyl acetic acid and 4-hydroxyphenyl lactic acid. This method might be helpful for cancer biomarkers discovery in urine. This article is protected by copyright. All rights reserved.

  17. Propionic acid production in glycerol/glucose co-fermentation by Propionibacterium freudenreichii subsp. shermanii.

    PubMed

    Wang, Zhongqiang; Yang, Shang-Tian

    2013-06-01

    Propionibacterium freudenreichii subsp. shermanii can ferment glucose and glycerol to propionic acid with acetic and succinic acids as two by-products. Propionic acid production from glucose was relatively fast (0.19 g/Lh) but gave low product yield (~0.39 g/g) and selectivity (P/A: ~2.6; P/S: ~4.8). In contrast, glycerol with a more reduced state gave a high propionic acid yield (~0.65 g/g) and selectivity (P/A: ~31; P/S: ~11) but low productivity (0.11 g/L h). On the other hand, co-fermentation of glycerol and glucose at an appropriate mass ratio gave both a high yield (0.54-0.65 g/g) and productivity (0.18-0.23 g/L h) with high product selectivity (P/A: ~14; P/S: ~10). The carbon flux distributions in the co-fermentation as affected by the ratio of glycerol/glucose were investigated. Finally, co-fermentation with cassava bagasse hydrolysate and crude glycerol in a fibrous-bed bioreactor was demonstrated, providing an efficient way for economic production of bio-based propionic acid.

  18. Microbial physiology of an anaerobic propionate-degrading consortium

    SciTech Connect

    Xun, L.

    1989-01-01

    A methanogenic propionate-degrading consortium, comprised of a strictly anaerobic chemoheterotroph and two types of methanogenic bacteria, is responsible for the complete conversion of propionate to CH{sub 4} and CO{sub 2} via the intermediate formation of acetate, H{sub 2}, and CO{sub 2}. Propionate oxidation by the heterotroph to acetate, H{sub 2} and CO{sub 2} proceeds only if H{sub 2} is removed through oxidation by CO{sub 2}-reducing methanogens. Acetate may only be catabolized anaerobically by one specific physiological group of bacteria, the aceticlastic methanogens, which produces CH{sub 4} and CO{sub 2} by cleaving acetate. Representatives of all three of these organisms have been studied. The effects of environmental factors such as temperature, pH, and nutrients on anaerobic propionate degradation was studied by enrichment cultures. From the propionate enrichment, the H{sub 2} using methanogen (strain LX1) and the propionate-degrading organism (strain LX2) were isolated. Both organisms have been characterized. In regard to the aceticlastic reaction, Methanosarcina mazei S-6 isolated by Mah (1980), was studied as the third member of the consortium. By changing the culture conditions, the morphology of M. mazei was manipulated from an aggregated to single cell form.

  19. Hydrogen production by fermentation using acetic acid and lactic acid.

    PubMed

    Matsumoto, Mitsufumi; Nishimura, Yasuhiko

    2007-03-01

    Microbial hydrogen production from sho-chu post-distillation slurry solution (slurry solution) containing large amounts of organic acids was investigated. The highest hydrogen producer, Clostridium diolis JPCC H-3, was isolated from natural environment and produced hydrogen at 6.03+/-0.15 ml from 5 ml slurry solution in 30 h. Interestingly, the concentration of acetic acid and lactic acid in the slurry solution decreased during hydrogen production. The substrates for hydrogen production by C. diolis JPCC H-3, in particular organic acids, were investigated in an artificial medium. No hydrogen was produced from acetic acid, propionic acid, succinic acid, or citric acid on their own. Hydrogen and butyric acid were produced from a mixture of acetic acid and lactic acid, showing that C. diolis. JPCC H-3 could produce hydrogen from acetic acid and lactic acid. Furthermore, calculation of the Gibbs free energy strongly suggests that this reaction would proceed. In this paper, we describe for the first time microbial hydrogen production from acetic acid and lactic acid by fermentation.

  20. 77 FR 31722 - New Animal Drugs; Change of Sponsor; Estradiol; Estradiol Benzoate and Testosterone Propionate...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-30

    ... and testosterone propionate) with TYLAN (tylosin tartrate). 200-221 COMPONENT TE-IS 522.2477 (trenbolone acetate and estradiol). COMPONENT TE-S (trenbolone acetate and estradiol). COMPONENT TE-G (trenbolone acetate and estradiol). COMPONENT TE-IS (trenbolone acetate and estradiol) with TYLAN...

  1. Fragrance material review on α-methylbenzyl propionate.

    PubMed

    McGinty, D; Letizia, C S; Api, A M

    2012-09-01

    A toxicologic and dermatologic review of α-methylbenzyl propionate when used as a fragrance ingredient is presented. α-Methylbenzyl propionate is a member of the fragrance structural group Aryl Alkyl Alcohol Simple Acid Esters (AAASAE). The AAASAE fragrance ingredients are prepared by reacting an aryl alkyl alcohol with a simple carboxylic acid (a chain of 1-4 carbons) to generate formate, acetate, propionate, butyrate, isobutyrate, and carbonate esters. This review contains a detailed summary of all available toxicology and dermatology papers that are related to this individual fragrance ingredient and is not intended as a stand-alone document. Available data for α-methylbenzyl propionate were evaluated, then summarized, and includes: physical properties, acute toxicity, skin irritation, skin sensitization data. A safety assessment of the entire AAASAE will be published simultaneously with this document. Please refer to Belsito et al. (2012) for an overall assessment of the safe use of this material and all AAASAE in fragrances.

  2. The Succinated Proteome

    SciTech Connect

    Merkley, Eric D.; Metz, Thomas O.; Smith, Richard D.; Baynes, John; Frizell, Norma

    2014-03-30

    Succination is a chemical modification of cysteine in protein by the Krebs cycle intermediate, fumarate, yielding S-(2-succino)cysteine (2SC). Intracellular fumarate concentration and succination of proteins are increased by hyperpolarization of the inner mitochondrial membrane, in concert with mitochondrial, endoplasmic reticulum (ER) and oxidative stress in adipocytes grown in high glucose medium and in adipose tissue in obesity and diabetes. Increased succination of proteins is also detected in the kidney of a fumarase conditional knock-out mouse which develops renal tumors. Keap1, the gatekeeper of the antioxidant response, was identified as a major succinated protein in renal cancer cells, suggesting that succination may play a role in activation of the antioxidant response. A wide range of proteins is subject to succination, including enzymes, adipokines, cytoskeletal proteins and ER chaperones with functional cysteine residues. There is also significant overlap between succinated and glutathionylated proteins, and with proteins containing cysteine residues that are readily oxidized to the sulfenic (cysteic) acid. Succination of adipocyte proteins is inhibited by uncouplers, which discharge the mitochondrial membrane potential (Δψm) and by ER stress inhibitors. 2SC serves as a biomarker of mitochondrial stress or dysfunction in chronic diseases, such as obesity, diabetes and cancer, and recent studies suggest that succination is a mechanistic link between mitochondrial dysfunction, oxidative and ER stress, and cellular progression toward apoptosis. In this article, we review the history of the succinated proteome and the challenges associated with measuring this non-enzymatic post-translational modification of proteins by proteomics approaches.

  3. Succinic acid production with Actinobacillus succinogenes ZT-130 in the presence of succinic acid.

    PubMed

    Corona-Gonzalez, Rosa Isela; Bories, Andre; González-Alvarez, Víctor; Snell-Castro, Raul; Toriz-González, Guillermo; Pelayo-Ortiz, Carlos

    2010-01-01

    Glucose fermentation with Actinobacillus succinogenes was carried out at different initial concentrations of succinic acid (SA(0)) to determine its effect on growth and on the production of succinic acid itself. The specific rates of biomass production, succinic, formic and acetic acids decreased with SA(0) (0-40 g/l). The partially dissociated form of succinic acid had a higher effect on cell growth and production of succinic acid as compared to the non-dissociated forms of the acids, a fact that has not been reported until now. Cell growth fitted the Jerusalimski model, and the Aiba-Shoda model was suitable for quantification of the inhibition for the production of succinic acid. The growth inhibition constants K(is) and K(ip) and their summatory were consistent with the experimental values obtained, i.e., 22 g/l for the produced acids and 38 g/l for total acids that were the limits at which the biomass formation ceased.

  4. Succinate oxidase in Neurospora.

    PubMed

    West, D J; Woodward, D O

    1973-02-01

    Two kinetically distinct states of succinate oxidase have been detected in the mitochondria of Neruospora crassa. One state has a K(m) for succinate of 4.1 x 10(-3)m, and the other has a K(m) for succinate of 3.5 x 10(-4)m. The high K(m) state was found in freshly extracted mitochondria from either 20- or 72-hr mycelium. However, the succinate oxidase activity in mitochondria from 20-hr mycelium rapidly deteriorated in vitro, leaving a stable residual activity with the lower K(m) for succinate. Adenosine triphosphate (ATP) plus Mg(2+) stabilized the high K(m) state in these preparations. The high K(m) state of succinate oxidase was further characterized by a two- to threefold increase in activity over the pH range 6.6 to 8.0 and by classical competitive inhibition by fumarate and malonate. By contrast, the low K(m) state of succinate oxidase showed a relatively flat response to pH over the range 6.6 to 8.0 and a nonclassical pattern of inhibition by fumarate and malonate, as shown by nonlinear plots of reciprocal velocity versus reciprocal substrate concentration in the presence of inhibitor or reciprocal velocity versus inhibitor concentration at fixed substrate concentrations. The relationship of mycelial age to the in vitro stability of succinate oxidase is considered with reference to probable changes in the relative pool sizes of extra- and intramitochondrial ATP in response to changes in the rate of glycolysis.

  5. Formation of propionate and butyrate by the human colonic microbiota.

    PubMed

    Louis, Petra; Flint, Harry J

    2017-01-01

    The human gut microbiota ferments dietary non-digestible carbohydrates into short-chain fatty acids (SCFA). These microbial products are utilized by the host and propionate and butyrate in particular exert a range of health-promoting functions. Here an overview of the metabolic pathways utilized by gut microbes to produce these two SCFA from dietary carbohydrates and from amino acids resulting from protein breakdown is provided. This overview emphasizes the important role played by cross-feeding of intermediary metabolites (in particular lactate, succinate and 1,2-propanediol) between different gut bacteria. The ecophysiology, including growth requirements and responses to environmental factors, of major propionate and butyrate producing bacteria are discussed in relation to dietary modulation of these metabolites. A detailed understanding of SCFA metabolism by the gut microbiota is necessary to underpin effective strategies to optimize SCFA supply to the host.

  6. High-Fat Diet Reduces the Formation of Butyrate, but Increases Succinate, Inflammation, Liver Fat and Cholesterol in Rats, while Dietary Fibre Counteracts These Effects

    PubMed Central

    Jakobsdottir, Greta; Xu, Jie; Molin, Göran; Ahrné, Siv; Nyman, Margareta

    2013-01-01

    Introduction Obesity is linked to type 2 diabetes and risk factors associated to the metabolic syndrome. Consumption of dietary fibres has been shown to have positive metabolic health effects, such as by increasing satiety, lowering blood glucose and cholesterol levels. These effects may be associated with short-chain fatty acids (SCFAs), particularly propionic and butyric acids, formed by microbial degradation of dietary fibres in colon, and by their capacity to reduce low-grade inflammation. Objective To investigate whether dietary fibres, giving rise to different SCFAs, would affect metabolic risk markers in low-fat and high-fat diets using a model with conventional rats for 2, 4 and 6 weeks. Material and Methods Conventional rats were administered low-fat or high-fat diets, for 2, 4 or 6 weeks, supplemented with fermentable dietary fibres, giving rise to different SCFA patterns (pectin – acetic acid; guar gum – propionic acid; or a mixture – butyric acid). At the end of each experimental period, liver fat, cholesterol and triglycerides, serum and caecal SCFAs, plasma cholesterol, and inflammatory cytokines were analysed. The caecal microbiota was analysed after 6 weeks. Results and Discussion Fermentable dietary fibre decreased weight gain, liver fat, cholesterol and triglyceride content, and changed the formation of SCFAs. The high-fat diet primarily reduced formation of SCFAs but, after a longer experimental period, the formation of propionic and acetic acids recovered. The concentration of succinic acid in the rats increased in high-fat diets with time, indicating harmful effect of high-fat consumption. The dietary fibre partly counteracted these harmful effects and reduced inflammation. Furthermore, the number of Bacteroides was higher with guar gum, while noticeably that of Akkermansia was highest with the fibre-free diet. PMID:24236183

  7. Effect of mesenteric vein infusion of propionate on splanchnic metabolism in primiparous Holstein cows.

    PubMed

    Casse, E A; Rulquin, H; Huntington, G B

    1994-11-01

    Our objective was to assess the effects of increased propionate supply on gut and liver function in lactating cows. Four multicatheterized, primiparous cows (30.4 +/- .5 kg/d of milk) were fed for ad libitum intake a diet of 50% alfalfa hay and 50% concentrate (20.6 +/- 1.9 kg/d of DM, 226 +/- 21 MJ/d of metabolizable energy, and 611 +/- 56 g/d of N). Each cow received intramesenteric infusions of NaCl (control) or Na-propionate (150 mmol/h of a 2.5 M solution) in a reversal design. After 72 h of infusion, blood flow (by indicator dilution) and net flux (venoarterial differences multiplied by blood flow) were measured across portal-drained viscera and the liver. Energy supply from feed consumed and from infusion was similar between treatments. Energy that was excreted as milk decreased with propionate infusion. Propionate infusion increased arterial concentration of propionate; decreased absorption of acetate, butyrate, and valerate; and decreased hepatic removal of L-lactate, butyrate, valerate, NEFA, and oxygen. Propionate infusion decreased splanchnic release of glucose and increased splanchnic release of acetate and alanine. Net flux of urea, BHBA, insulin, or glucagon was unaffected by treatments. Our data show a link between a greater proportion of energy supplied as propionate and decreased energy excreted as milk. This response was associated with decreased net removal of glucogenic and ketogenic substrates by the liver and increased supply of acetate for use by peripheral tissues.

  8. 21 CFR 184.1221 - Calcium propionate.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... Specific Substances Affirmed as GRAS § 184.1221 Calcium propionate. (a) Calcium propionate (C6H10CaO4, CAS Reg. No. 4075-81-4) is the calcium salt of propionic acid. It occurs as white crystals or a crystalline solid, possessing not more than a faint odor of propionic acid. It is prepared by...

  9. 21 CFR 184.1221 - Calcium propionate.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... Specific Substances Affirmed as GRAS § 184.1221 Calcium propionate. (a) Calcium propionate (C6H10CaO4, CAS Reg. No. 4075-81-4) is the calcium salt of propionic acid. It occurs as white crystals or a crystalline solid, possessing not more than a faint odor of propionic acid. It is prepared by...

  10. Succinic anhydrides from epoxides

    DOEpatents

    Coates, Geoffrey W.; Rowley, John M.

    2013-07-09

    Catalysts and methods for the double carbonylation of epoxides are disclosed. Each epoxide molecule reacts with two molecules of carbon monoxide to produce a succinic anhydride. The reaction is facilitated by catalysts combining a Lewis acidic species with a transition metal carbonyl complex. The double carbonylation is achieved in single process by using reaction conditions under which both carbonylation reactions occur without the necessity of isolating or purifying the product of the first carbonylation.

  11. Succinate-dependent energy generation and pyruvate dehydrogenase complex activity in isolated Ascaris suum mitochondria

    SciTech Connect

    Campbell, T.A.

    1988-01-01

    Body wall muscle from the parasitic nematode, Ascaris suum, contain unique anaerobic mitochondria that preferentially utilize fumarate and branched-chain enoyl CoA's as terminal electron acceptors instead of oxygen. While electron transport in these organelles is well characterized, the role of oxygen in succinate-dependent phosphorylation is still not clearly defined. Therefore, the present study was designed to more fully characterize succinate metabolism in these organelles as well as the in vitro regulation of a key mitochondrial enzyme, the pyruvate dehydrogenase complex (PDC). In the absence of added adenine nucleotides, incubations in succinate resulted in substantial elevations in intramitochrondrial ATP levels, but ATP/ADP ratios were considerably higher in incubations with malate. The stimulation of phosphorylation in aerobic incubations with succinate was rotenone sensitive and appears to be Site I dependent. Increase substrate level phosphorylation, coupled to propionate formation, or additional sites of electron-transport associated ATP synthesis were not significant. Under aerobic conditions, {sup 14}CO{sub 2} evolution from 1,4-({sup 14}C)succinate was stimulated and NADH/NAD{sup +} ratios were elevated, but the formation of {sup 14}C propionate was unchanged.

  12. Structures of microbial communities found in anaerobic batch runs that produce methane from propionic acid--Seeded from full-scale anaerobic digesters above a certain threshold.

    PubMed

    Kim, Woong; Shin, Seung Gu; Han, Gyuseong; Cho, Kyungjin; Hwang, Seokhwan

    2015-11-20

    The volatile fatty acid propionate inhibits anaerobic digestion during organic waste treatments. To examine potential microbial interactions that accelerate propionate oxidation, anaerobic digestion systems seeded with various types of anaerobic sludge were analyzed. Seed samples were collected from 10 different full-scale anaerobic reactors in South Korea. Propionate oxidation was estimated as the methane production rate per gram of propionate used per day. Two domestic sewage sludge showed the highest methane production rate values, 109.1 ± 4.2 and 74.5 ± 8.6 mL CH4/(g propionate ∙ d). A food waste recycling wastewater source exhibited the lowest methane production rate, 33.2 ± 2.6 mL CH4/(g propionate ∙ d). To investigate how the microbial community structure affected propionate oxidation, qualitative molecular analyses were carried out using denaturing gradient gel electrophoresis. Methanosaeta concilii, an aceticlastic methanogen, was detected in most batch runs. Smithella propionica, a unique propionate oxidizer and simultaneous producer of acetate, was found in domestic sewage sludge sources showing the highest methane production rate; in contrast, Desulfobulbus rhabdoformis, a sulfate reducer coupled with the consumption of acetate to be used as a precursor of methane, was observed in food waste recycling wastewater sludge source showing the lowest methane production rate. Thus, we propose that S. propionica, a syntrophic acetate producer using propionate, might cooperate with aceticlastic methanogens for high methane production during anaerobic digestion that included propionate.

  13. Multiple paths of electron flow to current in microbial electrolysis cells fed with low and high concentrations of propionate.

    PubMed

    Hari, Ananda Rao; Katuri, Krishna P; Gorron, Eduardo; Logan, Bruce E; Saikaly, Pascal E

    2016-07-01

    Microbial electrolysis cells (MECs) provide a viable approach for bioenergy generation from fermentable substrates such as propionate. However, the paths of electron flow during propionate oxidation in the anode of MECs are unknown. Here, the paths of electron flow involved in propionate oxidation in the anode of two-chambered MECs were examined at low (4.5 mM) and high (36 mM) propionate concentrations. Electron mass balances and microbial community analysis revealed that multiple paths of electron flow (via acetate/H2 or acetate/formate) to current could occur simultaneously during propionate oxidation regardless of the concentration tested. Current (57-96 %) was the largest electron sink and methane (0-2.3 %) production was relatively unimportant at both concentrations based on electron balances. At a low propionate concentration, reactors supplemented with 2-bromoethanesulfonate had slightly higher coulombic efficiencies than reactors lacking this methanogenesis inhibitor. However, an opposite trend was observed at high propionate concentration, where reactors supplemented with 2-bromoethanesulfonate had a lower coulombic efficiency and there was a greater percentage of electron loss (23.5 %) to undefined sinks compared to reactors without 2-bromoethanesulfonate (11.2 %). Propionate removal efficiencies were 98 % (low propionate concentration) and 78 % (high propionate concentration). Analysis of 16S rRNA gene pyrosequencing revealed the dominance of sequences most similar to Geobacter sulfurreducens PCA and G. sulfurreducens subsp. ethanolicus. Collectively, these results provide new insights on the paths of electron flow during propionate oxidation in the anode of MECs fed with low and high propionate concentrations.

  14. Recovery of succinic acid produced by fermentation of a metabolically engineered Mannheimia succiniciproducens strain.

    PubMed

    Song, Hyohak; Huh, Yun Suk; Lee, Sang Yup; Hong, Won Hi; Hong, Yeon Ki

    2007-12-01

    There have recently been much advances in the production of succinic acid, an important four-carbon dicarboxylic acid for many industrial applications, by fermentation of several natural and engineered bacterial strains. Mannheimia succiniciproducens MBEL55E isolated from bovine rumen is able to produce succinic acid with high efficiency, but also produces acetic, formic and lactic acids just like other anaerobic succinic acid producers. We recently reported the development of an engineered M. succiniciproducens LPK7 strain which produces succinic acid as a major fermentation product while producing much reduced by-products. Having an improved succinic acid producer developed, it is equally important to develop a cost-effective downstream process for the recovery of succinic acid. In this paper, we report the development of a simpler and more efficient method for the recovery of succinic acid. For the recovery of succinic acid from the fermentation broth of LPK7 strain, a simple process composed of a single reactive extraction, vacuum distillation, and crystallization yielded highly purified succinic acid (greater than 99.5% purity, wt%) with a high yield of 67.05wt%. When the same recovery process or even multiple reactive extraction steps were applied to the fermentation broth of MBEL55E, lower purity and yield of succinic acid were obtained. These results suggest that succinic acid can be purified in a cost-effective manner by using the fermentation broth of engineered LPK7 strain, showing the importance of integrating the strain development, fermentation and downstream process for optimizing the whole processes for succinic acid production.

  15. High-purity propionate production from glycerol in mixed culture fermentation.

    PubMed

    Chen, Yun; Wang, Ting; Shen, Nan; Zhang, Fang; Zeng, Raymond J

    2016-11-01

    High-purity propionate production from glycerol in mixed culture fermentation (MCF) induced by high ammonium concentration was investigated. Fed-batch experiments revealed that higher ammonium concentration (>2.9g/L) had simultaneous negative effects on acetate and propionate degradation. Propionate production and yield was up to 22.6g/L and 0.45g COD/g COD glycerol, respectively, with a purity of 96%. Sequential batch experiments demonstrated that the yields of propionate were 0.3±0.05, 0.32±0.01, and 0.34±0.03g COD/g COD at a glycerol concentration of 2.78, 4.38, and 5.56g/L, respectively, and the purity of propionate was 91-100%. Microbial community analysis showed that the phylum Firmicutes dominated the bacterial community at different glycerol concentrations. However, the Methanosaeta population decreased from 46% to 6% when glycerol concentration increased from 2.78 to 5.56g/L, resulting in lower acetate degradation rate. Thus, the present study might provide an alternative option for the production of propionate from glycerol via MCF.

  16. 21 CFR 184.1784 - Sodium propionate.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Sodium propionate. 184.1784 Section 184.1784 Food... Specific Substances Affirmed as GRAS § 184.1784 Sodium propionate. (a) Sodium propionate (C3H5NaO2, CAS Reg. No. 137-40-6) is the sodium salt of propionic acid. It occurs as colorless, transparent crystals or...

  17. 21 CFR 184.1784 - Sodium propionate.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Sodium propionate. 184.1784 Section 184.1784 Food... Specific Substances Affirmed as GRAS § 184.1784 Sodium propionate. (a) Sodium propionate (C3H5NaO2, CAS Reg. No. 137-40-6) is the sodium salt of propionic acid. It occurs as colorless, transparent crystals or...

  18. 21 CFR 184.1784 - Sodium propionate.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Sodium propionate. 184.1784 Section 184.1784 Food... Specific Substances Affirmed as GRAS § 184.1784 Sodium propionate. (a) Sodium propionate (C3H5NaO2, CAS Reg. No. 137-40-6) is the sodium salt of propionic acid. It occurs as colorless, transparent crystals or...

  19. 21 CFR 184.1784 - Sodium propionate.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Sodium propionate. 184.1784 Section 184.1784 Food... Specific Substances Affirmed as GRAS § 184.1784 Sodium propionate. (a) Sodium propionate (C3H5NaO2, CAS Reg. No. 137-40-6) is the sodium salt of propionic acid. It occurs as colorless, transparent crystals or...

  20. 21 CFR 184.1784 - Sodium propionate.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Sodium propionate. 184.1784 Section 184.1784 Food... GRAS § 184.1784 Sodium propionate. (a) Sodium propionate (C3H5NaO2, CAS Reg. No. 137-40-6) is the sodium salt of propionic acid. It occurs as colorless, transparent crystals or a granular...

  1. Reactivity of the sulfhydryl groups of soluble succinate dehydrogenase.

    PubMed

    Vinogradov, A D; Gavrikova, E V; Zuevsky, V V

    1976-04-01

    Soluble succinate dehydrogenase prepared by butanol extraction reacts with N-ethylmaleimide according to first-order kinetics with respect to both remaining active enzyme and the inhibitor concentration. Binding of the sulfhydryl groups of the enzyme prevents its alkylation by N-ethylmaleimide and inhibition by oxaloacetate. A kinetic analysis of the inactivation of alkylating reagent in the presence of succinate or malonate suggests that N-ethylmaleimide acts as a site-directed inhibitor. The apparent first-order rate constant of alkylation increases between pH 5.8 and 7.8 indicating a pKa value for the enzyme sulfhydryl group equal to 7.0 at 22 degrees C in 50 mM Tris-sufate buffer. Certain anions (phosphate, citrate, maleate and acetate) decrease the reactivity of the enzyme towards the alkylating reagent. Succinate/phenazine methosulfate reductase activity measured in the presence of a saturating concentration of succinate shows the same pH-dependence as the alkylation rate by N-ethylmaleimide. The mechanism of the first step of succinate oxidation, including a nucleophilic attack of substrate by the active-site sulfhydryl group, is discussed.

  2. Genetic manipulation of a metabolic enzyme and a transcriptional regulator increasing succinate excretion from unicellular cyanobacterium.

    PubMed

    Osanai, Takashi; Shirai, Tomokazu; Iijima, Hiroko; Nakaya, Yuka; Okamoto, Mami; Kondo, Akihiko; Hirai, Masami Y

    2015-01-01

    Succinate is a building block compound that the U.S. Department of Energy (DOE) has declared as important in biorefineries, and it is widely used as a commodity chemical. Here, we identified the two genes increasing succinate production of the unicellular cyanobacterium Synechocystis sp. PCC 6803. Succinate was excreted under dark, anaerobic conditions, and its production level increased by knocking out ackA, which encodes an acetate kinase, and by overexpressing sigE, which encodes an RNA polymerase sigma factor. Glycogen catabolism and organic acid biosynthesis were enhanced in the mutant lacking ackA and overexpressing sigE, leading to an increase in succinate production reaching five times of the wild-type levels. Our genetic and metabolomic analyses thus demonstrated the effect of genetic manipulation of a metabolic enzyme and a transcriptional regulator on succinate excretion from this cyanobacterium with the data based on metabolomic technique.

  3. Genetic manipulation of a metabolic enzyme and a transcriptional regulator increasing succinate excretion from unicellular cyanobacterium

    PubMed Central

    Osanai, Takashi; Shirai, Tomokazu; Iijima, Hiroko; Nakaya, Yuka; Okamoto, Mami; Kondo, Akihiko; Hirai, Masami Y.

    2015-01-01

    Succinate is a building block compound that the U.S. Department of Energy (DOE) has declared as important in biorefineries, and it is widely used as a commodity chemical. Here, we identified the two genes increasing succinate production of the unicellular cyanobacterium Synechocystis sp. PCC 6803. Succinate was excreted under dark, anaerobic conditions, and its production level increased by knocking out ackA, which encodes an acetate kinase, and by overexpressing sigE, which encodes an RNA polymerase sigma factor. Glycogen catabolism and organic acid biosynthesis were enhanced in the mutant lacking ackA and overexpressing sigE, leading to an increase in succinate production reaching five times of the wild-type levels. Our genetic and metabolomic analyses thus demonstrated the effect of genetic manipulation of a metabolic enzyme and a transcriptional regulator on succinate excretion from this cyanobacterium with the data based on metabolomic technique. PMID:26500619

  4. 21 CFR 556.710 - Testosterone propionate.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Testosterone propionate. 556.710 Section 556.710... Tolerances for Residues of New Animal Drugs § 556.710 Testosterone propionate. No residues of testosterone, resulting from the use of testosterone propionate, are permitted in excess of the following increments...

  5. 21 CFR 556.710 - Testosterone propionate.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Testosterone propionate. 556.710 Section 556.710... Tolerances for Residues of New Animal Drugs § 556.710 Testosterone propionate. No residues of testosterone, resulting from the use of testosterone propionate, are permitted in excess of the following increments...

  6. 21 CFR 556.710 - Testosterone propionate.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Testosterone propionate. 556.710 Section 556.710... Tolerances for Residues of New Animal Drugs § 556.710 Testosterone propionate. No residues of testosterone, resulting from the use of testosterone propionate, are permitted in excess of the following increments...

  7. 21 CFR 556.710 - Testosterone propionate.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Testosterone propionate. 556.710 Section 556.710... Tolerances for Residues of New Animal Drugs § 556.710 Testosterone propionate. No residues of testosterone, resulting from the use of testosterone propionate, are permitted in excess of the following increments...

  8. 21 CFR 556.710 - Testosterone propionate.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Testosterone propionate. 556.710 Section 556.710... Tolerances for Residues of New Animal Drugs § 556.710 Testosterone propionate. No residues of testosterone, resulting from the use of testosterone propionate, are permitted in excess of the following increments...

  9. 21 CFR 582.3784 - Sodium propionate.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Sodium propionate. 582.3784 Section 582.3784 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL....3784 Sodium propionate. (a) Product. Sodium propionate. (b) Conditions of use. This substance...

  10. 21 CFR 582.3784 - Sodium propionate.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Sodium propionate. 582.3784 Section 582.3784 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL....3784 Sodium propionate. (a) Product. Sodium propionate. (b) Conditions of use. This substance...

  11. 21 CFR 582.3784 - Sodium propionate.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Sodium propionate. 582.3784 Section 582.3784 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL....3784 Sodium propionate. (a) Product. Sodium propionate. (b) Conditions of use. This substance...

  12. 21 CFR 582.3784 - Sodium propionate.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Sodium propionate. 582.3784 Section 582.3784 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL....3784 Sodium propionate. (a) Product. Sodium propionate. (b) Conditions of use. This substance...

  13. 21 CFR 582.3784 - Sodium propionate.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Sodium propionate. 582.3784 Section 582.3784 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL....3784 Sodium propionate. (a) Product. Sodium propionate. (b) Conditions of use. This substance...

  14. 21 CFR 184.1081 - Propionic acid.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Propionic acid. 184.1081 Section 184.1081 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) DIRECT FOOD....1081 Propionic acid. (a) Propionic acid (C3H6O2, CAS Reg. No. 79-09-4) is an oily liquid having...

  15. 21 CFR 582.3081 - Propionic acid.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Propionic acid. 582.3081 Section 582.3081 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS... Propionic acid. (a) Product. Propionic acid. (b) Conditions of use. This substance is generally...

  16. 21 CFR 582.3081 - Propionic acid.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Propionic acid. 582.3081 Section 582.3081 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS... Propionic acid. (a) Product. Propionic acid. (b) Conditions of use. This substance is generally...

  17. 21 CFR 582.3081 - Propionic acid.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Propionic acid. 582.3081 Section 582.3081 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS... Propionic acid. (a) Product. Propionic acid. (b) Conditions of use. This substance is generally...

  18. 21 CFR 582.3081 - Propionic acid.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Propionic acid. 582.3081 Section 582.3081 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS... Propionic acid. (a) Product. Propionic acid. (b) Conditions of use. This substance is generally...

  19. 21 CFR 582.3081 - Propionic acid.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Propionic acid. 582.3081 Section 582.3081 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS... Propionic acid. (a) Product. Propionic acid. (b) Conditions of use. This substance is generally...

  20. Succination of proteins in diabetes.

    PubMed

    Frizzell, Norma; Lima, Maria; Baynes, John W

    2011-01-01

    Cysteine is arguably the most reactive amino acid in protein. A wide range of cysteine derivatives is formed in vivo, resulting from oxidation, nitrosation, alkylation and acylation reactions. This review describes succination of proteins, an irreversible chemical modification of cysteine by the Krebs cycle intermediate, fumarate, yielding S-(2-succinyl)cysteine (2SC). Intracellular fumarate concentration and succination of proteins are increased by hyperpolarization of the inner mitochondrial membrane and develop in concert with mitochondrial and oxidative stress in diabetes. Increased succination of glyceraldehyde-3-phosphate dehydrogenase explains the loss in specific activity of this enzyme in muscle of streptozotocin-diabetic rats and increased succination of adiponectin may explain the decreased secretion of adiponectin from adipose tissue in type 2 diabetes. In addition to GAPDH and adiponectin, other succinated proteins identified in adipocytes include cytoskeletal proteins (tubulin, actin) and chaperone proteins in the endoplasmic reticulum. Succination of adipocyte protein in vitro is inhibited by uncouplers of oxidative phosphorylation and by inhibitors of ER stress. 2SC serves as a biomarker of mitochondrial stress and recent studies suggest that succination is the mechanistic link between mitochondrial and ER stress in diabetes.

  1. Effects of laidlomycin propionate and monensin on the in vitro mixed ruminal microorganism fermentation.

    PubMed

    Domescik, E J; Martin, S A

    1999-08-01

    The objective of this study was to compare the effects of laidlomycin propionate and monensin on the in vitro fermentation of ground corn, Trypticase, or alfalfa hay by mixed ruminal microorganisms. Ruminal fluid was collected from two steers fed 9.27 kg DM of a high-concentrate (62.2% ground corn and 17.4% cottonseed hulls) diet per day and composited. In the first study, no ionophore was included in the diet; the diet in the second study contained 11.1 g of laidlomycin propionate per ton of feed. The animals were allowed an adjustment period of 14 d for each dietary treatment before samples were collected. When ruminal fluid from unadapted animals was used, both monensin and laidlomycin propionate decreased (P<.05) CH4 concentration and the acetate:propionate ratio with ground corn and alfalfa hay. Monensin reduced (P<.05) in vitro dry matter disappearance of alfalfa and increased (P<.05) final pH in the ground corn and alfalfa hay fermentations. Both laidlomycin propionate and monensin decreased (P<.05) concentrations of acetate, propionate, isobutyrate, isovalerate, CH4, and NH3 in Trypticase fermentations. When ruminal fluid from adapted animals was used, both ionophores still reduced the concentrations of most fermentation products. However, there was generally less inhibition compared with fermentations inoculated with unadapted mixed ruminal microorganisms. In the presence of 5 mM maltose, mixed ruminal bacteria produced high concentrations (10 to 11 mM) of lactate, and addition of both ionophores to these fermentations was effective in reducing (P<.05) lactate production. In conclusion, laidlomycin propionate alters the mixed ruminal microorganism fermentation in a manner similar to monensin, but, at the concentrations used in this study, monensin seemed to be a more potent inhibitor.

  2. 21 CFR 184.1081 - Propionic acid.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Propionic acid. 184.1081 Section 184.1081 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN... Substances Affirmed as GRAS § 184.1081 Propionic acid. (a) Propionic acid (C3H6O2, CAS Reg. No. 79-09-4)...

  3. 21 CFR 184.1081 - Propionic acid.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Propionic acid. 184.1081 Section 184.1081 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN... Substances Affirmed as GRAS § 184.1081 Propionic acid. (a) Propionic acid (C3H6O2, CAS Reg. No. 79-09-4)...

  4. 21 CFR 184.1081 - Propionic acid.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Propionic acid. 184.1081 Section 184.1081 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN... Substances Affirmed as GRAS § 184.1081 Propionic acid. (a) Propionic acid (C3H6O2, CAS Reg. No. 79-09-4)...

  5. 21 CFR 184.1081 - Propionic acid.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Propionic acid. 184.1081 Section 184.1081 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN... Substances Affirmed as GRAS § 184.1081 Propionic acid. (a) Propionic acid (C3H6O2, CAS Reg. No. 79-09-4)...

  6. Tocopheramine succinate and tocopheryl succinate: mechanism of mitochondrial inhibition and superoxide radical production.

    PubMed

    Gruber, Julia; Staniek, Katrin; Krewenka, Christopher; Moldzio, Rudolf; Patel, Anjan; Böhmdorfer, Stefan; Rosenau, Thomas; Gille, Lars

    2014-01-15

    Tocopherols (TOH) are lipophilic antioxidants which require the phenolic OH group for their redox activity. In contrast, non-redox active esters of α-TOH with succinate (α-TOS) were shown to possess proapoptotic activity in cancer cells. It was suggested that this activity is mediated via mitochondrial inhibition with subsequent O2(-) production triggering apoptosis and that the modification of the linker between the succinate and the lipophilic chroman may modulate this activity. However, the specific mechanism and the influence of the linker are not clear yet on the level of the mitochondrial respiratory chain. Therefore, this study systematically compared the effects of α-TOH acetate (α-TOA), α-TOS and α-tocopheramine succinate (α-TNS) in cells and submitochondrial particles (SMP). The results showed that not all cancer cell lines are highly sensitive to α-TOS and α-TNS. In HeLa cells α-TNS did more effectively reduce cell viability than α-TOS. The complex I activity of SMP was little affected by α-TNS and α-TOS while the complex II activity was much more inhibited (IC50=42±8μM α-TOS, 106±8μM α-TNS, respectively) than by α-TOA (IC50 >1000μM). Also the complex III activity was inhibited by α-TNS (IC50=137±6μM) and α-TOS (IC50=315±23μM). Oxygen consumption of NADH- or succinate-respiring SMP, involving the whole electron transfer machinery, was dose-dependently decreased by α-TOS and α-TNS, but only marginal effects were observed in the presence of α-TOA. In contrast to the similar inhibition pattern of α-TOS and α-TNS, only α-TOS triggered O2(-) formation in succinate- and NADH-respiring SMP. Inhibitor studies excluded complex I as O2(-) source and suggested an involvement of complex III in O2(-) production. In cancer cells only α-TOS was reproducibly able to increase O2(-) levels above the background level but neither α-TNS nor α-TOA. Furthermore, the stability of α-TNS in liver homogenates was significantly lower than that

  7. Phylogenetic distribution of three pathways for propionate production within the human gut microbiota

    PubMed Central

    Reichardt, Nicole; Duncan, Sylvia H; Young, Pauline; Belenguer, Alvaro; McWilliam Leitch, Carol; Scott, Karen P; Flint, Harry J; Louis, Petra

    2014-01-01

    Propionate is produced in the human large intestine by microbial fermentation and may help maintain human health. We have examined the distribution of three different pathways used by bacteria for propionate formation using genomic and metagenomic analysis of the human gut microbiota and by designing degenerate primer sets for the detection of diagnostic genes for these pathways. Degenerate primers for the acrylate pathway (detecting the lcdA gene, encoding lactoyl-CoA dehydratase) together with metagenomic mining revealed that this pathway is restricted to only a few human colonic species within the Lachnospiraceae and Negativicutes. The operation of this pathway for lactate utilisation in Coprococcus catus (Lachnospiraceae) was confirmed using stable isotope labelling. The propanediol pathway that processes deoxy sugars such as fucose and rhamnose was more abundant within the Lachnospiraceae (based on the pduP gene, which encodes propionaldehyde dehydrogenase), occurring in relatives of Ruminococcus obeum and in Roseburia inulinivorans. The dominant source of propionate from hexose sugars, however, was concluded to be the succinate pathway, as indicated by the widespread distribution of the mmdA gene that encodes methylmalonyl-CoA decarboxylase in the Bacteroidetes and in many Negativicutes. In general, the capacity to produce propionate or butyrate from hexose sugars resided in different species, although two species of Lachnospiraceae (C. catus and R. inulinivorans) are now known to be able to switch from butyrate to propionate production on different substrates. A better understanding of the microbial ecology of short-chain fatty acid formation may allow modulation of propionate formation by the human gut microbiota. PMID:24553467

  8. Succinate production in Escherichia coli

    PubMed Central

    Thakker, Chandresh; Martínez, Irene; San, Ka-Yiu; Bennett, George N.

    2012-01-01

    Succinate has been recognized as an important platform chemical that can be produced from biomass. While a number of organisms are capable of succinate production naturally, this review focuses on the engineering of Escherichia coli for production of the four-carbon dicarboxylic acid. Important features of a succinate production system are to achieve optimal balance of reducing equivalents generated by consumption of the feedstock, while maximizing the amount of carbon that is channeled to the product. Aerobic and anaerobic production strains have been developed and applied to production from glucose as well as other abundant carbon sources. Metabolic engineering methods and strain evolution have been used and supplemented by the recent application of systems biology and in silico modeling tools to construct optimal production strains. The metabolic capacity of the production strain, as well as the requirement for efficient recovery of succinate and the reliability of the performance under scale-up are important in the overall process. The costs of the overall biorefinery compatible process will determine the economical commercialization of succinate and its impact in larger chemical markets. PMID:21932253

  9. Degradation of Fructans and Production of Propionic Acid by Bacteroides thetaiotaomicron are Enhanced by the Shortage of Amino Acids

    PubMed Central

    Adamberg, Signe; Tomson, Katrin; Vija, Heiki; Puurand, Marju; Kabanova, Natalja; Visnapuu, Triinu; Jõgi, Eerik; Alamäe, Tiina; Adamberg, Kaarel

    2014-01-01

    Bacteroides thetaiotaomicron is commonly found in the human colon and stabilizes its ecosystem by catabolism of various polysaccharides. A model of cross-talk between the metabolism of amino acids and fructans in B. thetaiotaomicron was proposed. The growth of B. thetaiotaomicron DSM 2079 in two defined media containing mineral salts and vitamins, and supplemented with either 20 or 2 amino acids, was studied in an isothermal microcalorimeter. The polyfructans inulin (from chicory) and levan (synthesized using levansucrase from Pseudomonas syringae), two fructooligosaccharide preparations with different composition, sucrose and fructose were tested as substrates. The calorimetric power-time curves were substrate specific and typically multiauxic. A surplus of amino acids reduced the consumption of longer oligosaccharides (degree of polymerization > 3). Bacterial growth was not detected either in the carbohydrate free medium containing amino acids or in the medium with inulin as a sole carbohydrate. In amino acid-restricted medium, fermentation leading to acetic acid formation was dominant at the beginning of growth (up to 24 h), followed by increased lactic acid production, and mainly propionic and succinic acids were produced at the end of fermentation. In the medium supplemented with 20 amino acids, the highest production of d-lactate (82 ± 33 mmol/gDW) occurred in parallel with extensive consumption (up to 17 mmol/gDW) of amino acids, especially Ser, Thr, and Asp. The production of Ala and Glu was observed at growth on all substrates, and the production was enhanced under amino acid deficiency. The study revealed the influence of amino acids on fructan metabolism in B. thetaiotaomicron and showed that defined growth media are invaluable in elucidating quantitative metabolic profiles of the bacteria. Levan was shown to act as an easily degradable substrate for B. thetaiotaomicron. The effect of levan on balancing or modifying colon microbiota will

  10. Succinic Acid Production from Cheese Whey using Actinobacillus succinogenes 130 Z

    NASA Astrophysics Data System (ADS)

    Wan, Caixia; Li, Yebo; Shahbazi, Abolghasem; Xiu, Shuangning

    Actinobacillus succinogenes 130 Z was used to produce succinic acid from cheese whey in this study. At the presence of external CO2 supply, the effects of initial cheese whey concentration, pH, and inoculum size on the succinic acid production were studied. The by-product formation during the fermentation process was also analyzed. The highest succinic acid yield of 0.57 was obtained at initial cheese whey concentration of 50 g/L, while the highest succinic acid productivity of 0.58 g h-1 L-1 was obtained at initial cheese whey concentration of 100 g/L. Increase in pH and inoculum size caused higher succinic acid yield and productivity. At the preferred fermentation condition of pH 6.8, inoculum size of 5% and initial cheese whey concentration of 50 g/L, succinic acid yield of 0.57, and productivity of 0.44 g h-1 L-1 were obtained. Acetic acid and formic acid were the main by-products throughout the fermentation run of 48 h. It is feasible to produce succinic acid using lactose from cheese whey as carbon resource by A. succinogenes 130 Z.

  11. Nonezymatic formation of succinate in mitochondria under oxidative stress.

    PubMed

    Fedotcheva, Nadezhda I; Sokolov, Alexander P; Kondrashova, Mariya N

    2006-07-01

    The products of the reactions of mitochondrial 2-oxo acids with hydrogen peroxide and tert-butyl hydroperoxide (tert-BuOOH) were studied in a chemical system and in rat liver mitochondria. It was found by HPLC that the decarboxylation of alpha-ketoglutarate (KGL), pyruvate (PYR), and oxaloacetate (OA) by both oxidants results in the formation of succinate, acetate, and malonate, respectively. The two latter products do not metabolize in rat liver mitochondria, whereas succinate is actively oxidized, and its nonenzymatic formation from KGL may shunt the tricarboxylic acid (TCA) cycle upon inactivation of alpha-ketoglutarate dehydrogenase (KGDH) under oxidative stress, which is inherent in many diseases and aging. The occurrence of nonenzymatic oxidation of KGL in mitochondria was established by an increase in the CO(2) and succinate levels in the presence of the oxidants and inhibitors of enzymatic oxidation. H(2)O(2) and menadione as an inductor of reactive oxygen species (ROS) caused the formation of CO(2) in the presence of sodium azide and the production of succinate, fumarate, and malate in the presence of rotenone. These substrates were also formed from KGL when mitochondria were incubated with tert-BuOOH at concentrations that completely inhibit KGDH. The nonenzymatic oxidation of KGL can support the TCA cycle under oxidative stress, provided that KGL is supplied via transamination. This is supported by the finding that the strong oxidant such as tert-BuOOH did not impair respiration and its sensitivity to the transaminase inhibitor aminooxyacetate when glutamate and malate were used as substrates. The appearance of two products, KGL and fumarate, also favors the involvement of transamination. Thus, upon oxidative stress, nonenzymatic decarboxylation of KGL and transamination switch the TCA cycle to the formation and oxidation of succinate.

  12. Clobetasol propionate--where, when, why?

    PubMed

    Pels, Ragna; Sterry, Wolfram; Lademann, Jürgen

    2008-07-01

    Clobetasol propionate is the most potent of all topical steroids. It is successfully applied in the treatment of various skin diseases such as atopic dermatitis, psoriasis and vulvar lichen sclerosus. The therapy is, however, mainly symptomatic. A preventive effect is only reported in the treatment of the latter. Clobetasol propionate exerts antiinflammatory, immunosuppressive and antimitotic effects influencing the growth, differentiation and function of various cells and inhibiting cytokine production. Seven different dosage forms are available to deliver the drug to the living cells of the skin. Their choice might additionally affect patient compliance. The potency of clobetasol propionate, however, is accompanied by local and systemic side effects, such as skin atrophy and hypothalamic-pituitary-adrenal axis suppression. Patients applying clobetasol propionate must be well instructed in how to use it. Physicians prescribing clobetasol propionate should consider a diversity of factors and be able to answer the questions where, when and why.

  13. Succinate in the cancer-immune cycle.

    PubMed

    Jiang, Shuai; Yan, Wei

    2017-04-01

    Succinate is an important intermediate of the tricarboxylic acid (TCA) cycle. In mitochondria, it plays a crucial role in generating adenosine triphosphate. Succinate metabolism is also intertwined with the metabolism of other metabolites and with the "GABA shunt" of the glutamine pathway. Recently, it has become increasingly apparent that the roles of succinate extend into the realms of immunity and cancer. Succinate is a key modulator of the hypoxic response, an important player in tumorigenesis; succinate is also involved in protein succinylation, a novel posttranslational modification pathway. This expanding repertoire of succinate functions suggests that it has broad roles in cellular contexts. Mutations in enzymes such as succinate dehydrogenase (SDH) that participate in succinate-related pathways lead to various pathologies, including tumor formation and innate inflammatory processes. Succinate can have both pro- or anti-tumor effectiveness. Therefore, investigation of succinate as an inflammatory signal may increase our understanding of the cancer-immunity cycle involved in both inflammatory diseases and cancer. Here, we briefly review the emerging roles of succinate, extending beyond metabolism, into anti-cancer immunity. This expansion of succinate roles suggests that it may represent a novel class of regulators in inflammation, which act as key signals in human cancers.

  14. 21 CFR 582.1091 - Succinic acid.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Succinic acid. 582.1091 Section 582.1091 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS....1091 Succinic acid. (a) Product. Succinic acid. (b) Conditions of use. This substance is...

  15. 21 CFR 582.1091 - Succinic acid.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Succinic acid. 582.1091 Section 582.1091 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS....1091 Succinic acid. (a) Product. Succinic acid. (b) Conditions of use. This substance is...

  16. 21 CFR 582.1091 - Succinic acid.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Succinic acid. 582.1091 Section 582.1091 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS....1091 Succinic acid. (a) Product. Succinic acid. (b) Conditions of use. This substance is...

  17. 21 CFR 582.1091 - Succinic acid.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Succinic acid. 582.1091 Section 582.1091 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS....1091 Succinic acid. (a) Product. Succinic acid. (b) Conditions of use. This substance is...

  18. 21 CFR 582.1091 - Succinic acid.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Succinic acid. 582.1091 Section 582.1091 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS....1091 Succinic acid. (a) Product. Succinic acid. (b) Conditions of use. This substance is...

  19. Activite succino-deshydrogenasique des microsomes et mode d'incorporation du succinate 2,3-(14)C dans les acides gras des microsomes de foie de rat in vitro.

    PubMed

    Rous, S; Aubry, L; Bonini, F

    1970-03-16

    The incorporations of 2,3-(14)C-succinate 2-(14)C-acetate into fatty acids of different cellular fractions of rat liver were studied. Acetate was incorporated mainly into supernatant and succinate into microsomal fatty acids. Mitochondria only could intensively decarboxylate pyruvate. Avidine inhibited fatty acid synthesis from succinate mainly in the supernatant. It is suggested that succinate is an important physiological precursor of fatty acids in the liver and that an active succino-dehydrogenase is present in microsomes.

  20. Propionate supplementation improves nitrogen use by reducing urea flux in sheep.

    PubMed

    Agarwal, U; Hu, Q; Bequette, B J

    2015-10-01

    Feeding and postruminal infusion of propionate is known to increase N retention in ruminants. Our aim was to determine the role of rumen propionate on urea N recycling and gluconeogenesis in growing sheep. In Exp. 1, wether sheep ( = 6; 32.5 ± 3.57 kg BW) fitted with a rumen cannula were fed to 1.8 × ME requirement a concentrate-type ration (172 g CP/kg DM and 10.4 MJ ME/kg DM) and continuously infused into the rumen with isoenergetic (10% of dietary ME intake) solutions of either sodium acetate (control) or sodium propionate for 9-d periods in a crossover design. In Exp. 2, a different group of wether sheep ( = 5; 33.6 ± 3.70 kg BW) fitted with a rumen cannula were fed, on an isonitrogenous basis, either a control (151 g CP/kg DM and 8.4 MJ ME/kg DM) or sodium propionate-supplemented (139 g CP/kg DM and 8.9 MJ ME/kg DM) diet at 2-h intervals. [N] urea was continuously infused intravenously for the last 5 d of each period, and total urine was collected by vacuum and feces were collected by a harness bag. Over the last 12 h, [C]glucose was continuously infused intravenously and hourly blood samples were collected during the last 5 h. Propionate treatments increased ( < 0.001) the proportion of rumen propionate in both experiments. In Exp. 1, N retention was not affected by propionate infusion as compared with isoenergetic acetate. There was no effect on urea entry (synthesis) rate (UER) in Exp. 1; however, sodium propionate infusion tended ( < 0.1) to increase urinary urea elimination (UUE). In Exp. 2, feeding propionate increased ( < 0.01) N retention by 0.8 g N/d. In addition, UER was reduced by approximately 2 g urea N/d, leading to a reduction ( < 0.05) in UUE (7.0 vs. 6.2 g urea N/d). Between the 2 experiments, the proportion of UER recycled to the gut was greater with the forage-type diet in Exp. 2 (approximately 60%) compared with the concentrate-type diet in Exp. 1 (approximately 40%), although urea N fluxes across the gut remained unchanged in both

  1. [Progress in microbial production of succinic acid].

    PubMed

    Liu, Rongming; Liang, Liya; Wu, Mingke; Jiang, Min

    2013-10-01

    Succinic acid is one of the key intermediates in the tricarboxylic acid cycle (TCA)and has huge potentials in biopolymer, food, medicine applications. This article reviews recent research progress in the production of succinic acid by microbial fermentation, including discovery and screening of the succinic-acid-producing microbes, the progress of genetic engineering strategy and metabolic engineering technology for construction of succinic acid-producing strains, and fermentation process control and optimization. Finally, we discussed the limitation of current progress and proposed the future research needs for microbial production of succinic acid.

  2. Propionate-degrading bacterium, Syntrophobacter wolinii sp. nov. gen. nov. , from methanogenic ecosystems

    SciTech Connect

    Boone, D.R.; Bryant, M.P.

    1980-09-01

    A new genus and species of a nonmotile gram-negative rod, Syntrophobacter wolinii, is the first bacterium described which degrades propionate only in coculture with an H/sub 2/-using organism and in the absence of light or exogenous electron acceptors such as O/sub 2/, sulfate, or nitrate. It was isolated from methanogenic enrichments from an anaerobic municipal sewage digestor, using anaerobic roll tubes containing a medium with propionate as the energy source in association with an H/sub 2/-using, sulfate-reducing Desulfovibrio sp. which cannot utilize fatty acids other than formate. S. wolinii produced acetate and, presumably, CO/sub 2/ and H/sub 2/ (or formate) from propionate. In media without sulfate and with Methanospirillum hungatei, a methanogen that uses only H/sub 2/-CO/sub 2/ or formate as an energy source, acetate, methane, and, presumably, CO/sub 2/ were produced from propionate and only small amounts of Desulfovibrio sp. were present. Isolation in coculture with the methanogen was not successful. S. wolinii does not use other saturated fatty acids as energy sources. 2 figures, 3 tables.

  3. Flecainide acetate acetic acid solvates.

    PubMed

    Veldre, Kaspars; Actiņs, Andris; Eglite, Zane

    2011-02-01

    Flecainide acetate forms acetic acid solvates with 0.5 and 2 acetic acid molecules. Powder X-ray diffraction, differential thermal analysis/thermogravimetric, infrared, and potentiometric titration were used to determine the composition of solvates. Flecainide acetate hemisolvate with acetic acid decomposes to form a new crystalline form of flecainide acetate. This form is less stable than the already known polymorphic form at all temperatures, and it is formed due to kinetic reasons. Both flecainide acetate nonsolvated and flecainide acetate hemisolvate forms crystallize in monoclinic crystals, but flecainide triacetate forms triclinic crystals. Solvate formation was not observed when flecainide base was treated with formic acid, propanoic acid, and butanoic acid. Only nonsolvated flecainide salts were obtained in these experiments.

  4. Fermentation of glycerol to succinate by metabolically engineered strains of Escherichia coli.

    PubMed

    Zhang, Xueli; Shanmugam, K T; Ingram, Lonnie O

    2010-04-01

    The fermentative metabolism of Escherichia coli was reengineered to efficiently convert glycerol to succinate under anaerobic conditions without the use of foreign genes. Formate and ethanol were the dominant fermentation products from glycerol in wild-type Escherichia coli ATCC 8739, followed by succinate and acetate. Inactivation of pyruvate formate-lyase (pflB) in the wild-type strain eliminated the production of formate and ethanol and reduced the production of acetate. However, this deletion slowed growth and decreased cell yields due to either insufficient energy production or insufficient levels of electron acceptors. Reversing the direction of the gluconeogenic phosphoenolpyruvate carboxykinase reaction offered an approach to solve both problems, conserving energy as an additional ATP and increasing the pool of electron acceptors (fumarate and malate). Recruiting this enzyme through a promoter mutation (pck*) to increase expression also increased the rate of growth, cell yield, and succinate production. Presumably, the high NADH/NAD(+) ratio served to establish the direction of carbon flow. Additional mutations were also beneficial. Glycerol dehydrogenase and the phosphotransferase-dependent dihydroxyacetone kinase are regarded as the primary route for glycerol metabolism under anaerobic conditions. However, this is not true for succinate production by engineered strains. Deletion of the ptsI gene or any other gene essential for the phosphotranferase system was found to increase succinate yield. Deletion of pflB in this background provided a further increase in the succinate yield. Together, these three core mutations (pck*, ptsI, and pflB) effectively redirected carbon flow from glycerol to succinate at 80% of the maximum theoretical yield during anaerobic fermentation in mineral salts medium.

  5. Improved Succinate Production by Metabolic Engineering

    PubMed Central

    Cheng, Ke-Ke; Wang, Gen-Yu; Zeng, Jing; Zhang, Jian-An

    2013-01-01

    Succinate is a promising chemical which has wide applications and can be produced by biological route. The history of the biosuccinate production shows that the joint effort of different metabolic engineering approaches brings successful results. In order to enhance the succinate production, multiple metabolical strategies have been sought. In this review, different overproducers for succinate production, including natural succinate overproducers and metabolic engineered overproducers, are examined and the metabolic engineering strategies and performances are discussed. Modification of the mechanism of substrate transportation, knocking-out genes responsible for by-products accumulation, overexpression of the genes directly involved in the pathway, and improvement of internal NADH and ATP formation are some of the strategies applied. Combination of the appropriate genes from homologous and heterologous hosts, extension of substrate, integrated production of succinate, and other high-value-added products are expected to bring a desired objective of producing succinate from renewable resources economically and efficiently. PMID:23691505

  6. Improved succinate production by metabolic engineering.

    PubMed

    Cheng, Ke-Ke; Wang, Gen-Yu; Zeng, Jing; Zhang, Jian-An

    2013-01-01

    Succinate is a promising chemical which has wide applications and can be produced by biological route. The history of the biosuccinate production shows that the joint effort of different metabolic engineering approaches brings successful results. In order to enhance the succinate production, multiple metabolical strategies have been sought. In this review, different overproducers for succinate production, including natural succinate overproducers and metabolic engineered overproducers, are examined and the metabolic engineering strategies and performances are discussed. Modification of the mechanism of substrate transportation, knocking-out genes responsible for by-products accumulation, overexpression of the genes directly involved in the pathway, and improvement of internal NADH and ATP formation are some of the strategies applied. Combination of the appropriate genes from homologous and heterologous hosts, extension of substrate, integrated production of succinate, and other high-value-added products are expected to bring a desired objective of producing succinate from renewable resources economically and efficiently.

  7. 21 CFR 184.1091 - Succinic acid.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Succinic acid. 184.1091 Section 184.1091 Food and... Substances Affirmed as GRAS § 184.1091 Succinic acid. (a) Succinic acid (C4H6O4, CAS Reg. No. 110-15-6), also referred to as amber acid and ethylenesuccinic acid, is the chemical 1,4-butanedioic acid. It...

  8. 21 CFR 184.1091 - Succinic acid.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Succinic acid. 184.1091 Section 184.1091 Food and... Substances Affirmed as GRAS § 184.1091 Succinic acid. (a) Succinic acid (C4H6O4, CAS Reg. No. 110-15-6), also referred to as amber acid and ethylenesuccinic acid, is the chemical 1,4-butanedioic acid. It...

  9. 21 CFR 184.1091 - Succinic acid.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Succinic acid. 184.1091 Section 184.1091 Food and... Substances Affirmed as GRAS § 184.1091 Succinic acid. (a) Succinic acid (C4H6O4, CAS Reg. No. 110-15-6), also referred to as amber acid and ethylenesuccinic acid, is the chemical 1,4-butanedioic acid. It...

  10. 21 CFR 184.1091 - Succinic acid.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Succinic acid. 184.1091 Section 184.1091 Food and....1091 Succinic acid. (a) Succinic acid (C4H6O4, CAS Reg. No. 110-15-6), also referred to as amber acid and ethylenesuccinic acid, is the chemical 1,4-butanedioic acid. It is commercially prepared...

  11. 21 CFR 184.1091 - Succinic acid.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Succinic acid. 184.1091 Section 184.1091 Food and... Substances Affirmed as GRAS § 184.1091 Succinic acid. (a) Succinic acid (C4H6O4, CAS Reg. No. 110-15-6), also referred to as amber acid and ethylenesuccinic acid, is the chemical 1,4-butanedioic acid. It...

  12. Genetics Home Reference: succinic semialdehyde dehydrogenase deficiency

    MedlinePlus

    ... National Institute of Neurological Disorders and Stroke: Epilepsy Information Page Educational Resources (5 links) Boston Children's Hospital: Seizures and Epilepsy Disease InfoSearch: Succinic ...

  13. Mesoxalaldehyde acetals

    SciTech Connect

    Gordeeva, G.N.; Kalashnikov, S.M.; Popov, Yu.N.; Kruglov, E.A.; Imashev, U.B.

    1987-11-10

    The treatment of methylglyoxal acetals by alkyl nitrites in the presence of the corresponding aliphatic alcohols and hydrochloric acid leads to the formation of linear mesoxalaldehyde acetals, whose structure was established by NMR spectroscopy and mass spectrometry. The major pathways for the decomposition of these molecules upon electron impact were established.

  14. Effects of carbon dioxide on cell growth and propionic acid production from glycerol and glucose by Propionibacterium acidipropionici.

    PubMed

    Zhang, An; Sun, Jianxin; Wang, Zhongqiang; Yang, Shang-Tian; Zhou, Haiying

    2015-01-01

    The effects of CO2 on propionic acid production and cell growth in glycerol or glucose fermentation were investigated in this study. In glycerol fermentation, the volumetric productivity of propionic acid with CO2 supplementation reached 2.94g/L/day, compared to 1.56g/L/day without CO2. The cell growth using glycerol was also significantly enhanced with CO2. In addition, the yield and productivity of succinate, the main intermediate in Wood-Werkman cycle, increased 81% and 280%, respectively; consistent with the increased activities of pyruvate carboxylase and propionyl CoA transferase, two key enzymes in the Wood-Werkman cycle. However, in glucose fermentation CO2 had minimal effect on propionic acid production and cell growth. The carbon flux distributions using glycerol or glucose were also analyzed using a stoichiometric metabolic model. The calculated maintenance coefficient (mATP) increased 100%, which may explain the increase in the productivity of propionic acid in glycerol fermentation with CO2 supplement.

  15. Utilization of acetate by Beggiatoa.

    PubMed

    Burton, S D; Morita, R Y; Miller, W

    1966-03-01

    Burton, Sheril D. (Institute of Marine Science, University of Alaska, College), Richard Y. Morita, and Wayne Miller. Utilization of acetate by Beggiatoa. J. Bacteriol. 91:1192-1200. 1966.-A proposed system which would permit acetate incorporation into four-carbon compounds without the presence of key enzymes of the citric acid cycle or glyoxylate cycle is described. In this system, acetyl-coenzyme A (CoA) is condensed with glyoxylate to form malate, which, in turn, is converted to oxaloacetate. Oxaloacetate then reacts with glutamate to produce alpha-ketoglutarate, which is subsequently converted to isocitrate. Cleavage of isocitrate produces glyoxylate and succinate. Thus, the proposed system is similar to the glyoxylate bypass in that malate is produced from glyoxylate and acetyl-CoA, but differs from both the citric acid cycle and the glyoxylate bypass, since citrate and fumarate are not involved. Fumarase, aconitase, catalase, citritase, pyruvate kinase, enolase, phosphoenolpyruvate carboxylase, lactic dehydrogenase, alpha-ketoglutarate dehydrogenase, and condensing enzyme were not detectable in crude extracts of Beggiatoa. Succinate was oxidized by a soluble enzyme not associated with an electron-transport particle. Isocitrate was identified as the sole compound labeled when C(14)O(2) was added to a reduced nicotinamide adenine dinucleotide, CO(2) generating system (crystalline glucose-6-phosphate dehydrogenase and glucose-6-phosphate) in the presence of alpha-ketoglutarate.

  16. Toward homosuccinate fermentation: metabolic engineering of Corynebacterium glutamicum for anaerobic production of succinate from glucose and formate.

    PubMed

    Litsanov, Boris; Brocker, Melanie; Bott, Michael

    2012-05-01

    Previous studies have demonstrated the capability of Corynebacterium glutamicum for anaerobic succinate production from glucose under nongrowing conditions. In this work, we have addressed two shortfalls of this process, the formation of significant amounts of by-products and the limitation of the yield by the redox balance. To eliminate acetate formation, a derivative of the type strain ATCC 13032 (strain BOL-1), which lacked all known pathways for acetate and lactate synthesis (Δcat Δpqo Δpta-ackA ΔldhA), was constructed. Chromosomal integration of the pyruvate carboxylase gene pyc(P458S) into BOL-1 resulted in strain BOL-2, which catalyzed fast succinate production from glucose with a yield of 1 mol/mol and showed only little acetate formation. In order to provide additional reducing equivalents derived from the cosubstrate formate, the fdh gene from Mycobacterium vaccae, coding for an NAD(+)-coupled formate dehydrogenase (FDH), was chromosomally integrated into BOL-2, leading to strain BOL-3. In an anaerobic batch process with strain BOL-3, a 20% higher succinate yield from glucose was obtained in the presence of formate. A temporary metabolic blockage of strain BOL-3 was prevented by plasmid-borne overexpression of the glyceraldehyde 3-phosphate dehydrogenase gene gapA. In an anaerobic fed-batch process with glucose and formate, strain BOL-3/pAN6-gap accumulated 1,134 mM succinate in 53 h with an average succinate production rate of 1.59 mmol per g cells (dry weight) (cdw) per h. The succinate yield of 1.67 mol/mol glucose is one of the highest currently described for anaerobic succinate producers and was accompanied by a very low level of by-products (0.10 mol/mol glucose).

  17. Fragrance material review on 4-methylbenzyl acetate.

    PubMed

    McGinty, D; Letizia, C S; Api, A M

    2012-09-01

    A toxicologic and dermatologic review of 4-methylbenzyl acetate when used as a fragrance ingredient is presented. 4-Methylbenzyl acetate is a member of the fragrance structural group Aryl Alkyl Alcohol Simple Acid Esters (AAASAE). The AAASAE fragrance ingredients are prepared by reacting an aryl alkyl alcohol with a simple carboxylic acid (a chain of 1-4 carbons) to generate formate, acetate, propionate, butyrate, isobutyrate and carbonate esters. This review contains a detailed summary of all available toxicology and dermatology papers that are related to this individual fragrance ingredient and is not intended as a stand-alone document. Available data for 4-methylbenzyl acetate were evaluated, then summarized, and includes: physical properties, skin irritation, skin sensitization, and elicitation data. A safety assessment of the entire AAASAE will be published simultaneously with this document. Please refer to Belsito et al. (2012) for an overall assessment of the safe use of this material and all AAASAE in fragrances.

  18. Production of Succinic Acid for Lignocellulosic Hydrolysates

    SciTech Connect

    Davison, B.H.; Nghiem, J.

    2002-06-01

    The purpose of this Cooperative Research and Development Agreement (CRADA) is to add and test new metabolic activities to existing microbial catalysts for the production of succinic acid from renewables. In particular, they seek to add to the existing organism the ability to utilize xylose efficiently and simultaneously with glucose in mixtures of sugars or to add succinic acid production to another strain and to test the value of this new capability for production of succinic acid from industrial lignocellulosic hydrolyasates. The Contractors and Participant are hereinafter jointly referred to as the 'Parties'. Research to date in succinic acid fermentation, separation and genetic engineering has resulted in a potentially economical process based on the use of an Escherichia coli strain AFP111 with suitable characteristics for the production of succinic acid from glucose. Economic analysis has shown that higher value commodity chemicals can be economically produced from succinic acid based on repliminary laboratory findings and predicted catalytic parameters. The initial target markets include succinic acid itself, succinate salts, esters and other derivatives for use as deicers, solvents and acidulants. The other commodity products from the succinic acid platform include 1,4-butanediol, {gamma}-butyrolactone, 2-pyrrolidinone and N-methyl pyrrolidinone. Current economic analyses indicate that this platform is competitive with existing petrochemical routes, especially for the succinic acid and derivatives. The report presents the planned CRADA objectives followed by the results. The results section has a combined biocatalysis and fermentation section and a commercialization section. This is a nonproprietary report; additional proprietary information may be made available subject to acceptance of the appropriate proprietary information agreements.

  19. Effects of Eliminating Pyruvate Node Pathways and of Coexpression of Heterogeneous Carboxylation Enzymes on Succinate Production by Enterobacter aerogenes

    PubMed Central

    Yamamoto, Yoko; Fukui, Keita; Nishio, Yousuke; Hashiguchi, Kenichi; Usuda, Yoshihiro; Sode, Koji

    2014-01-01

    Lowering the pH in bacterium-based succinate fermentation is considered a feasible approach to reduce total production costs. Newly isolated Enterobacter aerogenes strain AJ110637, a rapid carbon source assimilator under weakly acidic (pH 5.0) conditions, was selected as a platform for succinate production. Our previous work showed that the ΔadhE/PCK strain, developed from AJ110637 with inactivated ethanol dehydrogenase and introduced Actinobacillus succinogenes phosphoenolpyruvate carboxykinase (PCK), generated succinate as a major product of anaerobic mixed-acid fermentation from glucose under weakly acidic conditions (pH <6.2). To further improve the production of succinate by the ΔadhE/PCK strain, metabolically engineered strains were designed based on the elimination of pathways that produced undesirable products and the introduction of two carboxylation pathways from phosphoenolpyruvate and pyruvate to oxaloacetate. The highest production of succinate was observed with strain ES04/PCK+PYC, which had inactivated ethanol, lactate, acetate, and 2,3-butanediol pathways and coexpressed PCK and Corynebacterium glutamicum pyruvate carboxylase (PYC). This strain produced succinate from glucose with over 70% yield (gram per gram) without any measurable formation of ethanol, lactate, or 2,3-butanediol under weakly acidic conditions. The impact of lowering the pH from 7.0 to 5.5 on succinate production in this strain was evaluated under pH-controlled batch culture conditions and showed that the lower pH decreased the succinate titer but increased its yield. These findings can be applied to identify additional engineering targets to increase succinate production. PMID:25416770

  20. Effects of eliminating pyruvate node pathways and of coexpression of heterogeneous carboxylation enzymes on succinate production by Enterobacter aerogenes.

    PubMed

    Tajima, Yoshinori; Yamamoto, Yoko; Fukui, Keita; Nishio, Yousuke; Hashiguchi, Kenichi; Usuda, Yoshihiro; Sode, Koji

    2015-02-01

    Lowering the pH in bacterium-based succinate fermentation is considered a feasible approach to reduce total production costs. Newly isolated Enterobacter aerogenes strain AJ110637, a rapid carbon source assimilator under weakly acidic (pH 5.0) conditions, was selected as a platform for succinate production. Our previous work showed that the ΔadhE/PCK strain, developed from AJ110637 with inactivated ethanol dehydrogenase and introduced Actinobacillus succinogenes phosphoenolpyruvate carboxykinase (PCK), generated succinate as a major product of anaerobic mixed-acid fermentation from glucose under weakly acidic conditions (pH <6.2). To further improve the production of succinate by the ΔadhE/PCK strain, metabolically engineered strains were designed based on the elimination of pathways that produced undesirable products and the introduction of two carboxylation pathways from phosphoenolpyruvate and pyruvate to oxaloacetate. The highest production of succinate was observed with strain ES04/PCK+PYC, which had inactivated ethanol, lactate, acetate, and 2,3-butanediol pathways and coexpressed PCK and Corynebacterium glutamicum pyruvate carboxylase (PYC). This strain produced succinate from glucose with over 70% yield (gram per gram) without any measurable formation of ethanol, lactate, or 2,3-butanediol under weakly acidic conditions. The impact of lowering the pH from 7.0 to 5.5 on succinate production in this strain was evaluated under pH-controlled batch culture conditions and showed that the lower pH decreased the succinate titer but increased its yield. These findings can be applied to identify additional engineering targets to increase succinate production.

  1. 40 CFR 721.8660 - Propionic acid methyl ester (generic).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Propionic acid methyl ester (generic... Substances § 721.8660 Propionic acid methyl ester (generic). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as a propionic acid methyl...

  2. 40 CFR 721.8660 - Propionic acid methyl ester (generic).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Propionic acid methyl ester (generic... Substances § 721.8660 Propionic acid methyl ester (generic). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as a propionic acid methyl...

  3. 40 CFR 721.8660 - Propionic acid methyl ester (generic).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Propionic acid methyl ester (generic... Substances § 721.8660 Propionic acid methyl ester (generic). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as a propionic acid methyl...

  4. 40 CFR 721.8660 - Propionic acid methyl ester (generic).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Propionic acid methyl ester (generic... Substances § 721.8660 Propionic acid methyl ester (generic). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as a propionic acid methyl...

  5. 40 CFR 721.8660 - Propionic acid methyl ester (generic).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Propionic acid methyl ester (generic... Substances § 721.8660 Propionic acid methyl ester (generic). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as a propionic acid methyl...

  6. Enhancement of propionic acid fraction in volatile fatty acids produced from sludge fermentation by the use of food waste and Propionibacterium acidipropionici.

    PubMed

    Chen, Yinguang; Li, Xiang; Zheng, Xiong; Wang, Dongbo

    2013-02-01

    Volatile fatty acids (VFA) can be used as the additional carbon source of biological nutrient removal (BNR), and the increase of propionic acid percentage in VFA has been reported to facilitate the performance of BNR. In this study a new method for significantly improving the propionic acid fraction in VFA derived from waste activated sludge was reported, which included (1) mixing food waste with sludge and pre-fermenting the mixture (first stage), and (2) separating the mixture, sterilizing the pre-fermentation liquid and fermenting it after inoculating Propionibacterium acidipropionici (second stage). By optimizing the first stage with response surface methodology, a propionic acid content of 68.4% with propionic acid concentration of 7.13 g COD/L could be reached in the second stage, which was much higher than that reported previously. Lactic acid was found to be the most abundant product of the first stage and it served as the substrate for propionic acid production in the second stage. Further investigation showed that during the first stage the addition of food waste to the pre-fermentation system of sludge significantly increased the generation of lactic acid due to the synergistic effect, which resulted in the improvement of propionic acid production in the second stage. Finally, the use of propionic acid-enriched VFA as a superior carbon source of BNR was tested, and its performance was observed to be much better than using acetic acid-enriched VFA derived from sludge by the previously documented method.

  7. [Breeding of Actinobacillus succiniogenes mutants with improved succinate production based on metabolic flux analysis].

    PubMed

    Pan, Lijun; Li, Xingjiang; Jiang, Shaotong; Wei, Zhaojun; Chen, Xiaohui; Cai, Licheng; Wang, Hefeng; Jiang, Jijun

    2008-09-01

    It is very important to obtain high yield mutant strains on the base of metabolic flux analysis of Actinobacillus succinogenes S.JST for the industrial bioconversion of succinic acid. The metabolic pathway was analized at first and the flux of the metabolic networks was calculated by matrix. In order to decrease acetic acid flux, the strains mutated by soft X-ray of synchronous radiation were screened on the plates with high concentration of fluoroacetic acid. For decreasing the metabolic flux of ethanol the site-directed mutagenesis was carried out for the reduction of alcohol dehydrogenase(Adh) specific activity. Then the enzyme activity determination and the gene sequence analysis of the mutant strain was compared with those of the parent strain. Metabolic flux analysis of the parent strain indicated that the flux of succinic acid was 1.78(mmol/g/h) and that the flux of acetic acid and ethanol were 0.60 (mmol/g/h) and 1.04( mmol/g/h), respectively. Meanwhile the metabolic pathway analysis showed that the ethanol metabolism enhanced the lacking of H electron donor during the synthesis of succinic acid and that the succinic acid flux was weakened by the metabolism of byproducts ethanol and acetic acid. Compared with the parent strain, the acetic acid flux of anti-fluoroacetic mutant strain S.JST1 was 0.024 (mmol/g/h), decreasing by 96%. Then the enzyme determination showed that the specific activity unit of phosphotransacetylase(Pta) decreased from 602 to 74 and a mutated site was founded in the pta gene of the mutant strain S.JST1. Compared with that of the parent strain S.JST1 the ethanol flux of adh-site-directed mutant strain S.JST2 was 0.020 (mmol/g/h), decreasing by 98%. Then the enzyme determination showed that the specific activity unit of Adh decreased from 585 to 62 and the yield of end product succinic acid was 65.7 (g/L). The interdiction of Adh and Pta decreased the metabolism of byproducts and the H electron donor was well balanced, thus the succinic

  8. Inhibition of membrane-bound succinate dehydrogenase by disulfiram.

    PubMed

    Jay, D

    1991-04-01

    The effect of disulfiram on succinate oxidase and succinate dehydrogenase activities of beef heart submitochondrial particles was studied. Results show that disulfiram inhibits both functions. Succinate and malonate suppress the inhibitory action of disulfiram when succinate dehydrogenase is stabilized in an active conformation. Disulfiram is not able to inhibit the enzyme when succinate dehydrogenase is inactivated by oxaloacetate. The inhibitory effect of disulfiram is reverted by the addition of dithiothreitol. From these results, it is proposed that disulfiram inhibits the utilization of succinate by a direct modification of an -SH group located in the catalytically active site of succinate dehydrogenase.

  9. Environmental and physiological factors affecting the succinate product ratio during carbohydrate fermentation by Actinobacillus sp. 130Z.

    PubMed

    Van der Werf, M J; Guettler, M V; Jain, M K; Zeikus, J G

    1997-06-01

    Actinobacillus sp. 130Z fermented glucose to the major products succinate, acetate, and formate. Ethanol was formed as a minor fermentation product. Under CO2-limiting conditions, less succinate and more ethanol were formed. The fermentation product ratio remained constant at pH values from 6.0 to 7.4. More succinate was produced when hydrogen was present in the gas phase. Actinobacillus sp. 130Z grew at the expense of fumarate and l-malate reduction, with hydrogen as an electron donor. Other substrates such as more-reduced carbohydrates (e.g., d-sorbitol) resulted in higher succinate and/or ethanol production. Actinobacillus sp. 130Z contained the key enzymes involved in the Embden-Meyerhof-Parnas and the pentose-phosphate pathways and contained high levels of phosphoenolpyruvate (PEP) carboxykinase, malate dehydrogenase, fumarase, fumarate reductase, pyruvate kinase, pyruvate formate-lyase, phosphotransacetylase, acetate kinase, malic enzyme, and oxaloacetate decarboxylase. The levels of PEP carboxykinase, malate dehydrogenase, and fumarase were significantly higher in Actinobacillus sp. 130Z than in Escherichia coli K-12 and accounted for the differences in succinate production. Key enzymes in end product formation in Actinobacillus sp. 130Z were regulated by the energy substrates.

  10. Role of succinic acid in chemical evolution

    NASA Technical Reports Server (NTRS)

    Negron-Mendoza, A.; Ponnamperuma, C.

    1982-01-01

    Succinic acid is converted into other carboxylic acids by ionizing radiation. The results obtained have been correlated with the ready formation of this compound in prebiotic experiments. Its role in biological systems may be related to its prebiotic occurrence.

  11. Interactions of alfalfa hay and sodium propionate on dairy calf performance and rumen development.

    PubMed

    Beiranvand, H; Ghorbani, G R; Khorvash, M; Nabipour, A; Dehghan-Banadaky, M; Homayouni, A; Kargar, S

    2014-01-01

    The objective of this experiment was to investigate the effects of different levels of alfalfa hay (AH) and sodium propionate (Pro) added to starter diets of Holstein calves on growth performance, rumen fermentation characteristics, and rumen development. Forty-two male Holstein calves (40±2kg of birth weight) were used in a complete randomized design with a 3×2 factorial arrangement of treatments. Dietary treatments were as follows: (1) control = concentrate only; (2) Pro = concentrate with 5% sodium propionate [dry matter (DM) basis]; (3) 5% AH = concentrate + 5% alfalfa hay (DM basis); (4) 5% AH + Pro = concentrate + 5% alfalfa hay + 5% sodium propionate (DM basis); (5) 10% AH = concentrate + 10% alfalfa hay (DM basis); and (6) 10% AH + Pro = concentrate + 10% alfalfa hay + 5% sodium propionate (DM basis). All calves were housed in individual pens bedded with sawdust until 10wk of age. They were given ad libitum access to water and starter throughout the experiment and were fed 2L of milk twice daily. Dry matter intake was recorded daily and body weight weekly. Calves from the control, 10% AH, and 10% AH + Pro treatments were euthanized after wk 10, and rumen wall samples were collected. Feeding of forage was found to increase overall dry matter intake, average daily gain, and final weight; supplementing sodium propionate had no effect on these parameters. Calves consuming forage had lower feed efficiency than those on the Pro diet. Rumen fluid in calves consuming forage had higher pH and greater concentrations of total volatile fatty acids and molar acetate. Morphometric parameters of the rumen wall substantiated the effect of AH supplementation, as plaque formation decreased macroscopically. Overall, the interaction between forage and sodium propionate did not affect calf performance parameters measured at the end of the experiment. Furthermore, inclusion of AH in starter diets positively enhanced the growth performance of male Holstein calves and influenced

  12. Thallium acetate

    Integrated Risk Information System (IRIS)

    Jump to main content . Integrated Risk Information System Recent Additions | Contact Us Search : All EPA IRIS • You are here : EPA Home • Research • Environmental Assessment • IRIS • IRIS Summaries Redirect Page As of September 30 , 2009 , the assessment summary for Thallium acetate is included in t

  13. Phenylmercuric acetate

    Integrated Risk Information System (IRIS)

    Phenylmercuric acetate ; CASRN 62 - 38 - 4 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinog

  14. Ethyl acetate

    Integrated Risk Information System (IRIS)

    Ethyl acetate ; CASRN 141 - 78 - 6 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinogenic Eff

  15. Ammonium acetate

    Integrated Risk Information System (IRIS)

    Ammonium acetate ; CASRN 631 - 61 - 8 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinogenic

  16. Vinyl acetate

    Integrated Risk Information System (IRIS)

    Vinyl acetate ; CASRN 108 - 05 - 4 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinogenic Eff

  17. [Interaction of succinate dehydrogenase and oxaloacetate].

    PubMed

    Kotliar, A B; Vinogradov, A D

    1984-04-01

    The equilibrium and rate constants for interaction of the reduced and oxidized membrane-bound succinate dehydrogenase (EC 1.3.99.1) with oxaloacetate were determined. The 10-fold decrease in the oxaloacetate affinity for the reduced enzyme was shown to be due to the 10-fold increase of the enzyme-inhibitor complex dissociation rate, which occurs upon its reduction. The rate of dissociation induced by succinate is 10 times higher than that induced by malonate in the submitochondrial particles, being equal in the soluble enzyme preparations. The rates of dissociation induced by malonate excess, or by the enzyme irreversibly utilizing oxaloacetate (transaminase in the presence of glutamate) are also equal. The data obtained suggest that succinate dehydrogenase interaction with succinate and oxaloacetate results from the competition for a single dicarboxylate-specific site. In submitochondrial particles all succinate dehydrogenase molecules are in redox equilibrium provided for by endogenous ubiquinone. No electronic equilibrium between the individual enzyme molecules exists, when succinate dehydrogenase is solubilized.

  18. Hypophagic effects of propionic acid are not attenuated during a 3-day infusion in the early postpartum period in Holstein cows.

    PubMed

    Stocks, S E; Allen, M S

    2013-07-01

    We previously showed that propionic acid was more hypophagic than acetic acid when infused intraruminally in cows in the postpartum period and that the degree of hypophagia from short-term propionic acid infusion (18 h) was related to the acetyl coenzyme A (CoA) concentration in the liver. The objective of this experiment was to evaluate adaptation over time with longer-term infusions over 3 d. Twelve multiparous cows (2-13 d postpartum) were blocked by calving date and assigned randomly to treatment sequence in a crossover design experiment. The experiment was 12 d long with covariate periods preceding each 3-d infusion period. Treatments were 1.0 M propionic acid or 1.0 M acetic acid, infused intraruminally at 0.5 mol of volatile fatty acids/h beginning 6 h before feeding and continuing for 78 h with 3 d between infusions. Propionic acid decreased dry matter intake (DMI) relative to acetic acid (15.9 vs. 17.0 kg/d). However, a period-by- treatment interaction was detected for DMI. During period 1, propionic acid decreased DMI relative to acetic acid (14.3 vs. 17.5 kg/d) because of a reduction in meal size (1.30 vs. 1.65 kg), with no effect on intermeal interval. Propionic acid decreased DMI over the first 4 h following feeding (5.86 vs. 8.23 kg) but did not affect DMI 4 to 24 h after feeding. The depression in DMI in period 1 was positively related to hepatic acetyl-CoA concentration during the covariate period. Propionic acid was increasingly more hypophagic than acetic acid as hepatic acetyl-CoA concentration was elevated. No treatment-by-day interaction for DMI was observed, suggesting little or no measurable adaptation to treatment over the 3-d infusion period. These results suggest that hypophagia from propionic acid is enhanced when hepatic acetyl-CoA concentrations are elevated, such as when cows are in a lipolytic state.

  19. Efficient production of succinic acid from Palmaria palmata hydrolysate by metabolically engineered Escherichia coli.

    PubMed

    Olajuyin, Ayobami Matthew; Yang, Maohua; Liu, Yilan; Mu, Tingzhen; Tian, Jiangnan; Adaramoye, Oluwatosin Adekunle; Xing, Jianmin

    2016-08-01

    Succinic acid, a C4 dicarboxylic acid is used in many fields such as food, agriculture, pharmaceutical and polymer industries. In this study, microbial production of succinic acid from Palmaria palmata was investigated for the first time. In engineered Escherichia coli KLPPP, lactate dehydrogenase, pyruvate formate lyase, phosphotransacetylase-acetate kinase and pyruvate oxidase genes were deleted while phosphoenolpyruvate carboxykinase was overexpressed. The recombinant exhibited higher molar yield of succinic acid on galactose (1.20±0.02mol/mol) than glucose (0.48±0.03mol/mol). The concentration and molar yield of succinic acid were 22.40±0.12g/L and 1.13±0.02mol/mol total sugar respectively after 72h dual phase fermentation from P. palmata hydrolysate which composed of glucose (12.57±0.17g/L) and galactose (18.03±0.10g/L). The results demonstrate that P. palmata red macroalgae biomass represents a novel and an economically alternative feedstock for biochemicals production.

  20. Manipulating pyruvate to acetyl-CoA conversion in Escherichia coli for anaerobic succinate biosynthesis from glucose with the yield close to the stoichiometric maximum.

    PubMed

    Skorokhodova, Alexandra Yu; Morzhakova, Anastasiya A; Gulevich, Andrey Yu; Debabov, Vladimir G

    2015-11-20

    Efficient succinate production in Escherichia coli is attained during anaerobic glucose fermentation in biosynthetic processes combining the reductive branch of the TCA cycle and the glyoxylate bypass. Pyruvate dehydrogenase (PDH) or pyruvate formate lyase (PFL) serves in E. coli as a source of acetyl-CoA, a substrate for the glyoxylate bypass. Depending on enzymes responsible for acetyl-CoA generation, the contribution of the glyoxylate bypass to the anaerobic succinate biosynthesis may vary to support redox balance resulting in diverse maximum achievable yield values. Anaerobic succinate biosynthesis from glucose was studied using E. coli strains with altered expression of genes encoding PFL and PDH. For acetyl-CoA formation by PFL, the yield of 1.32 mol succinate per mole of glucose was achieved with the theoretical value of 1.6 mol/mol. Involvement of PDH in anaerobic acetyl-CoA synthesis increased succinate yield up to 1.49 mol/mol, which is 89.8% of the predicted maximum (1.6(6) mol/mol). The maximum yield of 1.69 mol succinate per mol glucose, amounting to 98.8% of the stoichiometric maximum (1.71 mol/mol), was achieved with the strain possessing PDH as the primary anaerobic source of acetyl-CoA. During high cell density fermentation, the best engineered strain produced high amounts of succinate (570.7 mM) and only small quantities of acetate (11.9 mM).

  1. Oxidation of acetate through reactions of the citric acid cycle by Geobacter sulfurreducens in pure culture and in syntrophic coculture.

    PubMed

    Galushko, A S; Schink, B

    2000-11-01

    Geobacter sulfurreducens strain PCA oxidized acetate to CO2 via citric acid cycle reactions during growth with acetate plus fumarate in pure culture, and with acetate plus nitrate in coculture with Wolinella succinogenes. Acetate was activated by succinyl-CoA:acetate CoA-transferase and also via acetate kinase plus phosphotransacetylase. Citrate was formed by citrate synthase. Soluble isocitrate and malate dehydrogenases NADP+ and NAD+, respectively. Oxidation of 2-oxoglutarate was measured as benzyl viologen reduction and strictly CoA-dependent; a low activity was also observed with NADP+. Succinate dehydrogenase and fumarate ductase both were membrane-bound. Succinate oxidation was coupled to NADP+ reduction whereas fumarate reduction was coupled to NADPH and NADH Coupling of succinate oxidation to NADP+ or cytochrome(s) reduction required an ATP-dependent reversed electron transport. Net ATP synthesis proceeded exclusively through electron transport phosphorylation. During fumarate reduction, both NADPH and NADH delivered reducing equivalents into the electron transport chain, which contained a menaquinone. Overall, acetate oxidation with fumarate proceeded through an open loop of citric acid cycle reactions, excluding succinate dehydrogenase, with fumarate reductase as the key reaction for electron delivery, whereas acetate oxidation in the syntrophic coculture required the complete citric acid cycle.

  2. Methylmalonate inhibits succinate-supported oxygen consumption by interfering with mitochondrial succinate uptake.

    PubMed

    Mirandola, S R; Melo, D R; Schuck, P F; Ferreira, G C; Wajner, M; Castilho, R F

    2008-02-01

    The effect of methylmalonate (MMA) on mitochondrial succinate oxidation has received great attention since it could present an important role in energy metabolism impairment in methylmalonic acidaemia. In the present work, we show that while millimolar concentrations of MMA inhibit succinate-supported oxygen consumption by isolated rat brain or muscle mitochondria, there is no effect when either a pool of NADH-linked substrates or N,N,N',N'-tetramethyl-p-phenylendiamine (TMPD)/ascorbate were used as electron donors. Interestingly, the inhibitory effect of MMA, but not of malonate, on succinate-supported brain mitochondrial oxygen consumption was minimized when nonselective permeabilization of mitochondrial membranes was induced by alamethicin. In addition, only a slight inhibitory effect of MMA was observed on succinate-supported oxygen consumption by inside-out submitochondrial particles. In agreement with these observations, brain mitochondrial swelling experiments indicate that MMA is an important inhibitor of succinate transport by the dicarboxylate carrier. Under our experimental conditions, there was no evidence of malonate production in MMA-treated mitochondria. We conclude that MMA inhibits succinate-supported mitochondrial oxygen consumption by interfering with the uptake of this substrate. Although succinate generated outside the mitochondria is probably not a sig-nificant contributor to mitochondrial energy generation, the physiopathological implications of MMA-induced inhibition of substrate transport by the mitochondrial dicarboxylate carrier are discussed.

  3. Stable carbon isotope discrimination in rice field soil during acetate turnover by syntrophic acetate oxidation or acetoclastic methanogenesis

    NASA Astrophysics Data System (ADS)

    Conrad, Ralf; Klose, Melanie

    2011-03-01

    Rice fields are an important source for the greenhouse gas methane. In Italian rice field soil CH 4 is produced either by hydrogenotrophic and acetoclastic methanogenesis, or by hydrogenotrophic methanogenesis and syntrophic acetate oxidation when temperatures are below and above about 40-45 °C, respectively. In order to see whether these acetate consumption pathways differently discriminate the stable carbon isotopes of acetate, we measured the δ 13C of total acetate and acetate-methyl as well as the δ 13C of CO 2 and CH 4 in rice field soil that had been pre-incubated at 45 °C and then shifted to different temperatures between 25 and 50 °C. Acetate transiently accumulated to about 6 mM, which is about one-third of the amount of CH 4 produced, irrespective of the incubation temperature and the CH 4 production pathway involved. However, the patterns of δ 13C of the CH 4 and CO 2 produced were different at low (25, 30, 35 °C) versus high (40, 45, 50 °C) temperatures. These patterns were consistent with CH 4 being exclusively formed by hydrogenotrophic methanogenesis at high temperatures, and by a combination of acetoclastic and hydrogenotrophic methanogenesis at low temperatures. The patterns of δ 13C of total acetate and acetate-methyl were also different at high versus low temperatures, indicating the involvement of different pathways of production and consumption of acetate at the two temperature regimes. Isotope fractionation during consumption of the methyl group of acetate was more pronounced at low ( α = 1.010-1.025) than at high ( α = 1.0-1.01) temperatures indicating that acetoclastic methanogenesis exhibits a stronger isotope effect than syntrophic acetate oxidation. Small amounts of propionate also transiently accumulated and were analyzed for δ 13C. The δ 13C values slightly increased (by about 10‰) during production and consumption of propionate, but were not affected by incubation temperature. Collectively, our results showed distinct

  4. Evidence for chloroplastic succinate dehydrogenase participating in the chloroplastic respiratory and photosynthetic electron transport chains of Chlamydomonas reinhardtii

    SciTech Connect

    Willeford, K.O.; Gombos, Z.; Gibbs, M. )

    1989-07-01

    A method for isolating intact chloroplasts from Chlamydomonas reinhardtii F-60 was developed from the Klein, Chen, Gibbs, Platt-Aloia procedure. Protoplasts, generated by treatment with autolysine, were lysed with a solution of digitonin and fractionated on Percoll step gradients. The chloroplasts were assessed to be 90% intact (ferricyanide assay) and free from cytoplasmic contamination (NADP isocitrate dehydrogenase activity) and to range from 2 to 5% in mitochondrial contamination (cytochrome c oxidase activity). About 25% of the cellular succinate dehydrogenase activity (21.6 micromoles per milligram chlorophyll per hour, as determined enzymically) was placed within the chloroplast. Chloroplastic succinate dehydrogenase had a K{sub m} for succinate of 0.55 millimolar and was associated with the thylakoidal material derived from the intact chloroplasts. This same thylakoidal material, with an enzymic assay of 21.6 micromoles per milligram chlorophyll per hour was able to initiate a light-dependent uptake of oxygen at a rate of 16.4 micromoles per milligram chlorophyll per hour when supplied with succinate and methyl viologen. Malonate was an apparent competitive inhibitor of this reaction. The succinate dehydrogenase activity present in the chloroplast was sufficient to account for the photoanaerobic rate of acetate dissimilation in H{sub 2} adapted Chlamydomonas.

  5. 21 CFR 520.784 - Doxylamine succinate tablets.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Doxylamine succinate tablets. 520.784 Section 520...) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS ORAL DOSAGE FORM NEW ANIMAL DRUGS § 520.784 Doxylamine succinate tablets. (a) Specifications. The drug is in tablet form and contains doxylamine succinate as...

  6. 21 CFR 520.784 - Doxylamine succinate tablets.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Doxylamine succinate tablets. 520.784 Section 520...) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS ORAL DOSAGE FORM NEW ANIMAL DRUGS § 520.784 Doxylamine succinate tablets. (a) Specifications. The drug is in tablet form and contains doxylamine succinate as...

  7. 21 CFR 520.784 - Doxylamine succinate tablets.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Doxylamine succinate tablets. 520.784 Section 520...) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS ORAL DOSAGE FORM NEW ANIMAL DRUGS § 520.784 Doxylamine succinate tablets. (a) Specifications. The drug is in tablet form and contains doxylamine succinate as...

  8. 21 CFR 520.784 - Doxylamine succinate tablets.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Doxylamine succinate tablets. 520.784 Section 520...) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS ORAL DOSAGE FORM NEW ANIMAL DRUGS § 520.784 Doxylamine succinate tablets. (a) Specifications. The drug is in tablet form and contains doxylamine succinate as...

  9. 40 CFR 721.8657 - Cerium, hydroxy oleate propionate complexes.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Cerium, hydroxy oleate propionate... Specific Chemical Substances § 721.8657 Cerium, hydroxy oleate propionate complexes. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as...

  10. 40 CFR 721.8657 - Cerium, hydroxy oleate propionate complexes.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Cerium, hydroxy oleate propionate... Specific Chemical Substances § 721.8657 Cerium, hydroxy oleate propionate complexes. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as...

  11. 40 CFR 721.8657 - Cerium, hydroxy oleate propionate complexes.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Cerium, hydroxy oleate propionate... Specific Chemical Substances § 721.8657 Cerium, hydroxy oleate propionate complexes. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as...

  12. 40 CFR 721.8657 - Cerium, hydroxy oleate propionate complexes.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Cerium, hydroxy oleate propionate... Specific Chemical Substances § 721.8657 Cerium, hydroxy oleate propionate complexes. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as...

  13. 40 CFR 721.8657 - Cerium, hydroxy oleate propionate complexes.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Cerium, hydroxy oleate propionate... Specific Chemical Substances § 721.8657 Cerium, hydroxy oleate propionate complexes. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as...

  14. Microparticulate based topical delivery system of clobetasol propionate.

    PubMed

    Badıllı, Ulya; Sen, Tangül; Tarımcı, Nilüfer

    2011-09-01

    Psoriasis is a chronic, autoimmune skin disease affecting approximately 2% of the world's population. Clobetasol propionate which is a superpotent topical corticosteroid is widely used for topical treatment of psoriasis. Conventional dosage forms like creams and ointments are commonly prefered for the therapy. The purpose of this study was to develop a new topical delivery system in order to provide the prolonged release of clobetasol propionate and to reduce systemic absorption and side effects of the drug. Clobetasol propionate loaded-poly(D,L-lactic-co-glycolic acid) (PLGA) microspheres were prepared by oil-in-water emulsion-solvent evaporation technique. Particle size analysis, morphological characterization, DSC and XRD analyses and in vitro drug release studies were performed on the microparticle formulations. Emulgel formulations were prepared as an alternative for topical delivery of clobetasol propionate. In vitro drug release studies were carried out from the emulgel formulations containing pure drug and drug-loaded microspheres. In addition, the same studies were performed to determine the drug release from the commercial cream product of clobetasol propionate. The release of clobetasol propionate from the emulgel formulations was significantly higher than the commercial product. In addition, the encapsulation of clobetasol propionate in the PLGA microspheres significantly delayed the drug release from the emulgel formulation. As a result, the decrease in the side effects of clobetasol propionate by the formulation containing PLGA microspheres is expected.

  15. Heme electron transfer in peroxidases: the propionate e-pathway.

    PubMed

    Guallar, Victor

    2008-10-23

    Computational modeling offers a new insight about the electron transfer pathway in heme peroxidases. Available crystal structures have revealed an intriguing arrangement of the heme propionate side chains in heme-heme and heme-substrate complexes. By means of mixed quantum mechanical/molecular mechanics calculations, we study the involvement of these propionate groups into the substrate oxidation in ascorbate peroxidase and into the heme to heme electron transfer in bacterial cytochrome c peroxidase. By selectively turning on/off different quantum regions, we obtain the electron transfer pathway which directly involves the porphyrin ring and the heme propionates. Furthermore, in ascorbate peroxidase the presence of the substrate appears to be crucial for the activation of the electron transfer channel. The results might represent a general motif for electron transfer from/to the heme group and change our view for the propionate side chains as simple electrostatic binding anchors. We name the new mechanism "the propionate e-pathway".

  16. Immunoresponsive Gene 1 and Itaconate Inhibit Succinate Dehydrogenase to Modulate Intracellular Succinate Levels.

    PubMed

    Cordes, Thekla; Wallace, Martina; Michelucci, Alessandro; Divakaruni, Ajit S; Sapcariu, Sean C; Sousa, Carole; Koseki, Haruhiko; Cabrales, Pedro; Murphy, Anne N; Hiller, Karsten; Metallo, Christian M

    2016-07-01

    Metabolic reprogramming is emerging as a hallmark of the innate immune response, and the dynamic control of metabolites such as succinate serves to facilitate the execution of inflammatory responses in macrophages and other immune cells. Immunoresponsive gene 1 (Irg1) expression is induced by inflammatory stimuli, and its enzyme product cis-aconitate decarboxylase catalyzes the production of itaconate from the tricarboxylic acid cycle. Here we identify an immunometabolic regulatory pathway that links Irg1 and itaconate production to the succinate accumulation that occurs in the context of innate immune responses. Itaconate levels and Irg1 expression correlate strongly with succinate during LPS exposure in macrophages and non-immune cells. We demonstrate that itaconate acts as an endogenous succinate dehydrogenase inhibitor to cause succinate accumulation. Loss of itaconate production in activated macrophages from Irg1(-/-) mice decreases the accumulation of succinate in response to LPS exposure. This metabolic network links the innate immune response and tricarboxylic acid metabolism to function of the electron transport chain.

  17. Spectrophotometric determination of clobetasol propionate, halobetasol propionate, quinagolide hydrochloride, through charge transfer complexation.

    PubMed

    Mostafa, Azza A; Bebawy, Lories I; Refaat, Heba H

    2002-03-01

    Two spectrophotometric procedures are described for the determination of clobetasol propionate(I), halobetasol propionate(II) (corticosteroids) and quinagolide hydrochloride(III) (prolactin inhibitor). For corticosteroid drugs, the procedures are based on the formation of phenyl hydrazones of the corticosteroids which are subsequently subjected to charge transfer complexation reaction with either 2,3-dichloro-5,6-dicyanobenzoquinone (DDQ) as pi-acceptor or with iodine as sigma-acceptor. Prolactin inhibitor was reacted directly with the previous reagents. The molar ratios of the reactants were established and the experimental conditions were studied giving maximum absorption at 588 and 290 nm with DDQ and iodine methods, respectively for the three drugs. The concentration ranges were 20-150,50-300, and 20-80 microg ml(-1) in DDQ method for (I), (II), and (III), respectively and 13-20,15-40, and 8-32 microg ml(-1) in iodine method for (I), (II) and (III), respectively.

  18. Alternative system of succinate oxidation in glyoxysomes of higher plants.

    PubMed

    Igamberdiev, A U; Popov, V N; Falaleeva, M I

    1995-07-03

    Succinate oxidation in scutella of germinating seeds of wheat and maize was investigated. Besides oxidation via succinate dehydrogenase (SDH; EC 1.3.99.1), an alternative path of succinate oxidation insensitive to SDH inhibitors--malonate and thenoyltrifluoroacetone (TTFA)--was revealed. Using isopicnic sucrose gradient it was shown that this path is localized in glyoxysomal membranes. Glyoxysomal succinate oxidase (GSO) converts succinate directly into malate with the production of hydrogen peroxide identified using auxiliary enzymes malate dehydrogenase and peroxidase. GSO is most active during the intensive operation of the glyoxylate cycle (3-5 days of germination). Quinacrine, the inhibitor of flavine-containing oxidases, strongly suppressed the activity of GSO. Km for succinate is 18 mM for GSO from maize scutellum. It is concluded that in scutella of cereal seeds the glyoxysomal succinate oxidation non-linked with ATP synthesis operates.

  19. Regulation of insulin secretion and proinsulin biosynthesis by succinate.

    PubMed

    Attali, Veronique; Parnes, Marcela; Ariav, Yafa; Cerasi, Erol; Kaiser, Nurit; Leibowitz, Gil

    2006-11-01

    Succinate stimulates insulin secretion and proinsulin biosynthesis. We studied the effects of reduced nicotinamide adenine dinucleotide phosphate (NADPH)-modulating pathways on glucose- and succinate-stimulated insulin secretion and proinsulin biosynthesis in the rat and the insulin-resistant Psammomys obesus. Disruption of the anaplerotic pyruvate/malate shuttle by phenylacetic acid inhibited glucose- and succinate-stimulated insulin secretion and succinate-stimulated proinsulin biosynthesis in both species. In contrast, phenylacetic acid failed to inhibit glucose-stimulated proinsulin biosynthesis in P. obesus islets. Inhibition of the NADPH-consuming enzyme neuronal nitric oxide synthase (nNOS) with l-N(G)-nitro-l-arginine methyl ester or with N(G)-monomethyl-l-arginine(G) doubled succinate-stimulated insulin secretion in rat islets, suggesting that succinate- and nNOS-derived signals interact to regulate insulin secretion. In contrast, nNOS inhibition had no effect on succinate-stimulated proinsulin biosynthesis in both species. In P. obesus islets, insulin secretion was not stimulated by succinate in the absence of glucose, whereas proinsulin biosynthesis was increased 5-fold. Conversely, under stimulating glucose levels, succinate doubled insulin secretion, indicating glucose-dependence. Pyruvate ester and inhibition of nNOS partially mimicked the permissive effect of glucose on succinate-stimulated insulin secretion, suggesting that anaplerosis-derived signals render the beta-cells responsive to succinate. We conclude that beta-cell anaplerosis via pyruvate carboxylase is important for glucose- and succinate-stimulated insulin secretion and for succinate-stimulated proinsulin biosynthesis. In P. obesus, pyruvate/malate shuttle dependent and independent pathways that regulate proinsulin biosynthesis coexist; the latter can maintain fuel stimulated biosynthetic activity when the succinate-dependent pathway is inhibited. nNOS signaling is a negative regulator

  20. Fragrance material review on ethyl phenyl carbinyl acetate.

    PubMed

    McGinty, D; Letizia, C S; Api, A M

    2012-09-01

    A toxicologic and dermatologic review of ethyl phenyl carbinyl acetate when used as a fragrance ingredient is presented. Ethyl phenyl carbinyl acetate is a member of the fragrance structural group Aryl Alkyl Alcohol Simple Acid Esters (AAASAE). The AAASAE fragrance ingredients are prepared by reacting an aryl alkyl alcohol with a simple carboxylic acid (a chain of 1-4 carbons) to generate formate, acetate, propionate, butyrate, isobutyrate and carbonate esters. This review contains a detailed summary of all available toxicology and dermatology papers that are related to this individual fragrance ingredient and is not intended as a stand-alone document. Available data for ethyl phenyl carbinyl acetate were evaluated, then summarized, and includes: physical properties; acute toxicity; skin irritation; and skin sensitization data. A safety assessment of the entire AAASAE will be published simultaneously with this document; please refer to Belsito et al. (2012) for an overall assessment of the safe use of this material and all AAASAE in fragrances.

  1. Fragrance material review on 2-(p-tolyloxy)ethyl acetate.

    PubMed

    McGinty, D; Letizia, C S; Api, A M

    2012-09-01

    A toxicologic and dermatologic review of 2-(p-tolyloxy)ethyl acetate when used as a fragrance ingredient is presented. 2-(p-tolyloxy)ethyl acetate is a member of the fragrance structural group aryl alkyl alcohol simple acid esters (AAASAE). The AAASAE fragrance ingredients are prepared by reacting an aryl alkyl alcohol with a simple carboxylic acid (a chain of 1-4 carbons) to generate formate, acetate, propionate, butyrate, isobutyrate and carbonate esters. This review contains a detailed summary of all available toxicology and dermatology papers that are related to this individual fragrance ingredient and is not intended as a stand-alone document. Available data for 2-(p-tolyloxy)ethyl acetate were evaluated, then summarized, and includes physical properties data. A safety assessment of the entire AAASAE will be published simultaneously with this document. Please refer to Belsito et al. (2012) for an overall assessment of the safe use of this material and all AAASAE in fragrances.

  2. Identification of two prpDBC gene clusters in Corynebacterium glutamicum and their involvement in propionate degradation via the 2-methylcitrate cycle.

    PubMed

    Claes, Wilfried A; Pühler, Alfred; Kalinowski, Jörn

    2002-05-01

    Genome sequencing revealed that the Corynebacterium glutamicum genome contained, besides gltA, two additional citrate synthase homologous genes (prpC) located in two different prpDBC gene clusters, which were designated prpD1B1C1 and prpD2B2C2. The coding regions of the two gene clusters as well as the predicted gene products showed sequence identities of about 70 to 80%. Significant sequence similarities were found also to the prpBCDE operons of Escherichia coli and Salmonella enterica, which are known to encode enzymes of the propionate-degrading 2-methylcitrate pathway. Homologous and heterologous overexpression of the C. glutamicum prpC1 and prpC2 genes revealed that their gene products were active as citrate synthases and 2-methylcitrate synthases. Growth tests showed that C. glutamicum used propionate as a single or partial carbon source, although the beginning of the exponential growth phase was strongly delayed by propionate for up to 7 days. Compared to growth on acetate, the specific 2-methylcitrate synthase activity increased about 50-fold when propionate was provided as the sole carbon source, suggesting that in C. glutamicum the oxidation of propionate to pyruvate occurred via the 2-methylcitrate pathway. Additionally, two-dimensional gel electrophoresis experiments combined with mass spectrometry showed strong induction of the expression of the C. glutamicum prpD2B2C2 genes by propionate as an additional carbon source. Mutational analyses revealed that only the prpD2B2C2 genes were essential for the growth of C. glutamicum on propionate as a sole carbon source, while the function of the prpD1B1C1 genes remains obscure.

  3. Succinate transport by free-living forms of Rhizobium japonicum.

    PubMed Central

    McAllister, C F; Lepo, J E

    1983-01-01

    We have demonstrated that the transport of succinate into the cells of Rhizobium japonicum strains USDA 110 and USDA 217 is severely inhibited by cyanide, azide, and 2,4-dinitrophenol, but not by arsenate. These results suggest an active mechanism of transport that is dependent on an energized membrane, but does not directly utilize ATP. The apparent Km for succinate was 3.8 microM for strain USDA 110 and 1.8 microM for strain USDA 217; maximal transport velocities were 1.5 and 3.3 nmol of succinate per min per mg of protein, respectively. The expression of the succinate uptake activity was inducible rather than constitutive, with succinate and structurally related compounds being the most effective inducers. The mechanism showed some specificity for succinate and similar organic acids; fumarate and L-malate were classical competitive inhibitors of the system. In general, the best competing compounds were also the best carbon substrates for induction of succinate uptake activity. EDTA inhibited the transport of succinate, implying a role for divalent cations in the system. When various divalent cations were used to reconstitute EDTA-inhibited activity, Ca2+ was most effective, followed by Mg2+, which restored activity at about half the efficiency of Ca2+. Growth media that were supplemented with increased Ca2+ concentration supported more rapid growth with succinate as the carbon substrate, and cells from such media showed higher specific activities of succinate transport. PMID:6402487

  4. Enhanced succinate production from glycerol by engineered Escherichia coli strains.

    PubMed

    Li, Qing; Wu, Hui; Li, Zhimin; Ye, Qin

    2016-10-01

    In this study, an engineered strain Escherichia coli MLB (ldhA(-)pflB(-)) was constructed for production of succinate from glycerol. The succinate yield was 0.37mol/mol in anaerobic culture, however, the growth and glycerol consumption rates were very slow, resulting in a low succinate level. Two-stage fermentation was performed in flasks, and the succinate yield reached 0.93mol/mol, but the succinate titer was still low. Hence, overexpression of malate dehydrogenase, malic enzyme, phosphoenolpyruvate (PEP) carboxylase and PEP carboxykinase (PCK) from E. coli, and pyruvate carboxylase from Corynebacterium glutamicum in MLB was investigated for improving succinate production. Overexpression of PCK resulted in remarkable enhancement of glycerol consumption and succinate production. In flask experiments, the succinate concentration reached 118.1mM, and in a 1.5-L bioreactor the succinate concentration further increased to 360.2mM. The highest succinate yield achieved 0.93mol/mol, which was 93% of the theoretical yield, in the anaerobic stage.

  5. Characterization of Two Tetrachloroethene-Reducing, Acetate-Oxidizing Anaerobic Bacteria and Their Description as Desulfuromonas michiganensis sp. nov.

    PubMed Central

    Sung, Youlboong; Ritalahti, Kirsti M.; Sanford, Robert A.; Urbance, John W.; Flynn, Shannon J.; Tiedje, James M.; Löffler, Frank E.

    2003-01-01

    Two tetrachlorethene (PCE)-dechlorinating populations, designated strains BB1 and BRS1, were isolated from pristine river sediment and chloroethene-contaminated aquifer material, respectively. PCE-to-cis-1,2-dichloroethene-dechlorinating activity could be transferred in defined basal salts medium with acetate as the electron donor and PCE as the electron acceptor. Taxonomic analysis based on 16S rRNA gene sequencing placed both isolates within the Desulfuromonas cluster in the δ subdivision of the Proteobacteria. PCE was dechlorinated at rates of at least 139 nmol min−1 mg of protein−1 at pH values between 7.0 and 7.5 and temperatures between 25 and 30°C. Dechlorination also occurred at 10°C. The electron donors that supported dechlorination included acetate, lactate, pyruvate, succinate, malate, and fumarate but not hydrogen, formate, ethanol, propionate, or sulfide. Growth occurred with malate or fumarate alone, whereas oxidation of the other electron donors depended strictly on the presence of fumarate, malate, ferric iron, sulfur, PCE, or TCE as an electron acceptor. Nitrate, sulfate, sulfite, thiosulfate, and other chlorinated compounds were not used as electron acceptors. Sulfite had a strong inhibitory effect on growth and dechlorination. Alternate electron acceptors (e.g., fumarate or ferric iron) did not inhibit PCE dechlorination and were consumed concomitantly. The putative fumarate, PCE, and ferric iron reductases were induced by their respective substrates and were not constitutively present. Sulfide was required for growth. Both strains tolerated high concentrations of PCE, and dechlorination occurred in the presence of free-phase PCE (dense non-aqueous-phase liquids). Repeated growth with acetate and fumarate as substrates yielded a BB1 variant that had lost the ability to dechlorinate PCE. Due to the 16S rRNA gene sequence differences with the closest relatives and the unique phenotypic characteristics, we propose that the new isolates are

  6. BER-Myriant Succinic Acid Biorefinery

    SciTech Connect

    Shmorhun, Mark

    2015-12-31

    Myriant Corporation (Myriant) has successfully produced the bioproduct succinic acid by the fermentation of glucose at a commercial scale operation in Lake Providence, Louisiana. The MySAB facility (Myriant Succinic Acid Biorefinery) came on stream in May 2013 and has been producing product since then. The MySAB facility is a demonstration-scale plant, capable of utilizing sorghum grits and commercially available dextrose, to ferment glucose into succinic acid. A downstream processing train has demonstrated the ability to produce an industrial, a standard and a polymer grade product. It consists of cell separation, membrane filtration, continuous chromatography, polishing to remove ionic and color bodies impurities, and final evaporation and crystallization. A by-product of the process is ammonium sulfate which is sold as a liquid fertilizer product. Since 2007 when development work began in the Woburn, Massachusetts R&D laboratories, the succinic acid bio-process has evolved through: Process development (microbiology, fermentation, and downstream) – R&D development laboratories; Piloting efforts at Fermic S.A. de C.V., Mexico City, Mexico – upstream and downstream processes; Design, construction, commissioning, and commercial production operations at the MySAB facility Additionally, Myriant became a wholly-owned subsidiary of the PTT Global Chemical Plc., Thailand, in late 2015, their investment into and support of Myriant goes back to 2011. The support of PTT Global Chemical Plc. helped to improve the upstream and downstream processes, and produce significant metric ton quantities of high quality bio-based succinic acid. The product has gone into a number of commercial markets worldwide for customer applications, development and production. The experience base gained via operations at the MySAB facility since May 2013, along with continued R&D development efforts involving Microbiology, Fermentation, and Downstream processes, at both the Woburn, Massachusetts

  7. Proteomic analysis on acetate metabolism in Citrobacter sp. BL-4.

    PubMed

    Kim, Young-Man; Lee, Sung-Eun; Park, Byeoung-Soo; Son, Mi-Kyung; Jung, Young-Mi; Yang, Seung-Ok; Choi, Hyung-Kyoon; Hur, Sung-Ho; Yum, Jong Hwa

    2012-01-01

    Mass production of glucosamine (GlcN) using microbial cells is a worthy approach to increase added values and keep safety problems in GlcN production process. Prior to set up a microbial cellular platform, this study was to assess acetate metabolism in Citrobacter sp. BL-4 (BL-4) which has produced a polyglucosamine PGB-2. The LC-MS analysis was conducted after protein separation on the 1D-PAGE to accomplish the purpose of this study. 280 proteins were totally identified and 188 proteins were separated as acetate-related proteins in BL-4. Acetate was converted to acetyl-CoA by acetyl-CoA synthetase up-regulated in the acetate medium. The glyoxylate bypass in the acetate medium was up-regulated with over-expression of isocitrate lyases and 2D-PAGE confirmed this differential expression. Using (1)H-NMR analysis, the product of isocitrate lyases, succinate, increased about 15 times in the acetate medium. During acetate metabolism proteins involved in the lipid metabolism and hexosamine biosynthesis were over-expressed in the acetate medium, while proteins involved in TCA cycle, pentose phosphate cycle and purine metabolism were down-regulated. Taken together, the results from the proteomic analysis can be applied to improve GlcN production and to develop metabolic engineering in BL-4.

  8. Blend miscibility of cellulose propionate with poly(N-vinyl pyrrolidone-co-methyl methacrylate).

    PubMed

    Sugimura, Kazuki; Teramoto, Yoshikuni; Nishio, Yoshiyuki

    2013-10-15

    The blend miscibility of cellulose propionate (CP) with poly(N-vinyl pyrrolidone-co-methyl methacrylate) (P(VP-co-MMA)) was investigated. The degree of substitution (DS) of CP used ranged from 1.6 to >2.9, and samples for the vinyl polymer component were prepared in a full range of VP:MMA compositions. Through DSC analysis and solid-state (13)C NMR and FT-IR measurements, we revealed that CPs of DS<2.7 were miscible with P(VP-co-MMA)s of VP≥~10mol% on a scale within a few nanometers, in virtue of hydrogen-bonding interactions between CP-hydroxyls and VP-carbonyls. When the DS of CP exceeded 2.7, the miscibility was restricted to the polymer pairs using P(VP-co-MMA)s of VP=ca. 10-40 mol%; the scale of mixing in the blends concerned was somewhat larger (ca. 5-20 nm), however. The appearance of such a "miscibility window" was interpretable as an effect of intramolecular repulsion in the copolymer component. Results of DMA and birefringence measurements indicated that the miscible blending of CP with the vinyl polymer invited synergistic improvements in thermomechanical and optical properties of the respective constituent polymers. Additionally, it was found that the VP:MMA composition range corresponding to the miscibility window was expanded by modification of the CP component into cellulose acetate propionate.

  9. Acute pancreatitis and acute renal failure complicating doxylamine succinate intoxication.

    PubMed

    Lee, Yang Deok; Lee, Soo Teik

    2002-06-01

    Doxylamine succinate is an antihistaminic drugwith additional hypnotic, anticholinergic and local anesthetic effects first described in 1948. In Korea and many other countries, it is a common-over-the counter medication frequently involved in overdoses. Clinical symtomatology of doxylamine succinate overdose includes somnolence, coma, seizures, mydriasis, tachycardia, psychosis, and rhabdomyolysis. A serious complication may be rhabdomyolysis with subsequent impairment of renal function and acute renal failure. We report a case of acute renal failure and acute pancreatitis complicating a doxylamine succinate intoxication.

  10. Transport of acetate and sodium in sheep omasum: mutual, but asymmetric interactions.

    PubMed

    Ali, O; Shen, Z; Tietjen, U; Martens, H

    2006-06-01

    We have studied the transport of acetate across the isolated epithelium of sheep omasum; no net transport was observed (J(ms) approximately = J(sm)) under Ussing chamber conditions. Low mucosal pH (pH 6.4) significantly enhanced J(ms) acetate and the transport rates of acetate increased linearly and significantly (r2=0.99) with the luminal acetate concentration. The presence of another short chain fatty acid (propionate) did not affect J(ms) acetate significantly. Neither addition of 1 mmol l(-1) DIDS to the mucosal side nor HCO3 replacement caused changes of J(ms) acetate; this does not support the assumption of acetate transport via anion exchange. Addition of 1 mmol l(-1) amiloride to the mucosal side significantly decreased acetate fluxes at high mucosal acetate concentration (100 mmol l(-1)) and low pH (6.4) indicating interaction between acetate uptake in the undissociated form, intracellular release of protons and activation of Na+/H+ exchange (NHE). However, the mutual interaction between Na transport via NHE and acetate transport is asymmetric. Stimulation or inhibition of Na transport via NHE is much more pronounced than the corresponding changes of acetate fluxes. Thus, the obtained results support the conclusion that acetate is transported via simple diffusion and probably predominantly in the protonated form, thereby explaining the positive and mutual interaction between Na transport and short chain fatty acids.

  11. The Common Gut Microbe Eubacterium hallii also Contributes to Intestinal Propionate Formation.

    PubMed

    Engels, Christina; Ruscheweyh, Hans-Joachim; Beerenwinkel, Niko; Lacroix, Christophe; Schwab, Clarissa

    2016-01-01

    Eubacterium hallii is considered an important microbe in regard to intestinal metabolic balance due to its ability to utilize glucose and the fermentation intermediates acetate and lactate, to form butyrate and hydrogen. Recently, we observed that E. hallii is capable of metabolizing glycerol to 3-hydroxypropionaldehyde (3-HPA, reuterin) with reported antimicrobial properties. The key enzyme for glycerol to 3-HPA conversion is the cobalamin-dependent glycerol/diol dehydratase PduCDE which also utilizes 1,2-propanediol (1,2-PD) to form propionate. Therefore our primary goal was to investigate glycerol to 3-HPA metabolism and 1,2-PD utilization by E. hallii along with its ability to produce cobalamin. We also investigated the relative abundance of E. hallii in stool of adults using 16S rRNA and pduCDE based gene screening to determine the contribution of E. hallii to intestinal propionate formation. We found that E. hallii utilizes glycerol to produce up to 9 mM 3-HPA but did not further metabolize 3-HPA to 1,3-propanediol. Utilization of 1,2-PD in the presence and absence of glucose led to the formation of propanal, propanol and propionate. E. hallii formed cobalamin and was detected in stool of 74% of adults using 16S rRNA gene as marker gene (n = 325). Relative abundance of the E. hallii 16S rRNA gene ranged from 0 to 0.59% with a mean relative abundance of 0.044%. E. hallii PduCDE was detected in 63 to 81% of the metagenomes depending on which subunit was investigated beside other taxons such as Ruminococcus obeum, R. gnavus, Flavonifractor plautii, Intestinimonas butyriciproducens, and Veillonella spp. In conclusion, we identified E. hallii as a common gut microbe with the ability to convert glycerol to 3-HPA, a step that requires the production of cobalamin, and to utilize 1,2-PD to form propionate. Our results along with its ability to use a broad range of substrates point at E. hallii as a key species within the intestinal trophic chain with the potential to

  12. The Common Gut Microbe Eubacterium hallii also Contributes to Intestinal Propionate Formation

    PubMed Central

    Engels, Christina; Ruscheweyh, Hans-Joachim; Beerenwinkel, Niko; Lacroix, Christophe; Schwab, Clarissa

    2016-01-01

    Eubacterium hallii is considered an important microbe in regard to intestinal metabolic balance due to its ability to utilize glucose and the fermentation intermediates acetate and lactate, to form butyrate and hydrogen. Recently, we observed that E. hallii is capable of metabolizing glycerol to 3-hydroxypropionaldehyde (3-HPA, reuterin) with reported antimicrobial properties. The key enzyme for glycerol to 3-HPA conversion is the cobalamin-dependent glycerol/diol dehydratase PduCDE which also utilizes 1,2-propanediol (1,2-PD) to form propionate. Therefore our primary goal was to investigate glycerol to 3-HPA metabolism and 1,2-PD utilization by E. hallii along with its ability to produce cobalamin. We also investigated the relative abundance of E. hallii in stool of adults using 16S rRNA and pduCDE based gene screening to determine the contribution of E. hallii to intestinal propionate formation. We found that E. hallii utilizes glycerol to produce up to 9 mM 3-HPA but did not further metabolize 3-HPA to 1,3-propanediol. Utilization of 1,2-PD in the presence and absence of glucose led to the formation of propanal, propanol and propionate. E. hallii formed cobalamin and was detected in stool of 74% of adults using 16S rRNA gene as marker gene (n = 325). Relative abundance of the E. hallii 16S rRNA gene ranged from 0 to 0.59% with a mean relative abundance of 0.044%. E. hallii PduCDE was detected in 63 to 81% of the metagenomes depending on which subunit was investigated beside other taxons such as Ruminococcus obeum, R. gnavus, Flavonifractor plautii, Intestinimonas butyriciproducens, and Veillonella spp. In conclusion, we identified E. hallii as a common gut microbe with the ability to convert glycerol to 3-HPA, a step that requires the production of cobalamin, and to utilize 1,2-PD to form propionate. Our results along with its ability to use a broad range of substrates point at E. hallii as a key species within the intestinal trophic chain with the potential to

  13. [The application of succine in sports].

    PubMed

    S V, Okovityi; S V, Rad'Ko

    2015-01-01

    The development of energy deficiency in the course of physical exercises that eventually leads to serious derangement of the energy metabolism is an important component of the deterioration of physical and intellectual working capacity. The most promising approach to the correction of impaired physical and intellectual working capacity associated with energy deficiency consists in the application of pharmaceutical preparations containing intermediate products of the tricarbonic acid cycle. Of great promise in this context is succinic acid by virtue of its oxidation in endogenous reactions that constitutes the physiological adaptive mechanism by which resistance of the organism to oxygen deficiency is promoted.

  14. Evaluation of an integrated biorefinery based on fractionation of spent sulphite liquor for the production of an antioxidant-rich extract, lignosulphonates and succinic acid.

    PubMed

    Alexandri, Maria; Papapostolou, Harris; Komaitis, Michael; Stragier, Lutgart; Verstraete, Willy; Danezis, Georgios P; Georgiou, Constantinos A; Papanikolaou, Seraphim; Koutinas, Apostolis A

    2016-08-01

    Spent sulphite liquor (SSL) has been used for the production of lignosulphonates (LS), antioxidants and bio-based succinic acid. Solvent extraction of SSL with isopropanol led to the separation of approximately 80% of the total LS content, whereas the fermentations carried out using the pretreated SSL with isopropanol led to the production of around 19g/L of succinic acid by both Actinobacillus succinogenes and Basfia succiniciproducens. Fractionation of SSL via nanofiltration to separate the LS and solvent extraction using ethyl acetate to separate the phenolic compounds produced a detoxified sugar-rich stream that led to the production of 39g/L of succinic acid by B. succiniciproducens. This fractionation scheme resulted also in the production of 32.4g LS and 1.15g phenolic-rich extract per 100g of SSL. Both pretreatment schemes removed significant quantities of metals and heavy metals. This novel biorefinery concept could be integrated in acidic sulphite pulping mills.

  15. 78 FR 76567 - Tall Oil, Polymer With Polyethylene Glycol and Succinic Anhydride Monopolyisobutylene Derivs...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-12-18

    ... AGENCY 40 CFR Part 180 Tall Oil, Polymer With Polyethylene Glycol and Succinic Anhydride... oil, polymer with polyethylene glycol and succinic anhydride monopolyisobutylene derivs. (CAS Reg. No... residues of tall oil, polymer with polyethylene glycol and succinic anhydride monopolyisobutylene...

  16. Blockade of dendritic cell development by bacterial fermentation products butyrate and propionate through a transporter (Slc5a8)-dependent inhibition of histone deacetylases.

    PubMed

    Singh, Nagendra; Thangaraju, Muthusamy; Prasad, Puttur D; Martin, Pamela M; Lambert, Nevin A; Boettger, Thomas; Offermanns, Stefan; Ganapathy, Vadivel

    2010-09-03

    Mammalian colon harbors trillions of bacteria, yet there is no undue inflammatory response by the host against these bacteria under normal conditions. The bacterial fermentation products acetate, propionate, and butyrate are believed, at least in part, to be responsible for these immunosuppressive effects. Dendritic cells play an essential role in presentation of antigens to T lymphocytes and initiation of adaptive immune responses. Here we report that butyrate and propionate block the generation of dendritic cells from bone marrow stem cells, without affecting the generation of granulocytes. This effect is dependent on the Na(+)-coupled monocarboxylate transporter Slc5a8, which transports butyrate and propionate into cells, and on the ability of these two bacterial metabolites to inhibit histone deacetylases. Acetate, which is also a substrate for Slc5a8 but not an inhibitor of histone deacetylases, does not affect dendritic cell development, indicating the essential role of histone deacetylase inhibition in the process. The blockade of dendritic cell development by butyrate and propionate is associated with decreased expression of the transcription factors PU.1 and RelB. Butyrate also elicits its biologic effects through its ability to activate the G-protein-coupled receptor Gpr109a, but this mechanism is not involved in butyrate-induced blockade of dendritic cell development. The participation of Slc5a8 and the non-involvement of Gpr109a in butyrate effects have been substantiated using bone marrow cells obtained from Slc5a8(-/-) and Gpr109a(-/-) mice. These findings uncover an important mechanism underlying the anti-inflammatory functions of the bacterial fermentation products butyrate and propionate.

  17. Blockade of Dendritic Cell Development by Bacterial Fermentation Products Butyrate and Propionate through a Transporter (Slc5a8)-dependent Inhibition of Histone Deacetylases

    PubMed Central

    Singh, Nagendra; Thangaraju, Muthusamy; Prasad, Puttur D.; Martin, Pamela M.; Lambert, Nevin A.; Boettger, Thomas; Offermanns, Stefan; Ganapathy, Vadivel

    2010-01-01

    Mammalian colon harbors trillions of bacteria, yet there is no undue inflammatory response by the host against these bacteria under normal conditions. The bacterial fermentation products acetate, propionate, and butyrate are believed, at least in part, to be responsible for these immunosuppressive effects. Dendritic cells play an essential role in presentation of antigens to T lymphocytes and initiation of adaptive immune responses. Here we report that butyrate and propionate block the generation of dendritic cells from bone marrow stem cells, without affecting the generation of granulocytes. This effect is dependent on the Na+-coupled monocarboxylate transporter Slc5a8, which transports butyrate and propionate into cells, and on the ability of these two bacterial metabolites to inhibit histone deacetylases. Acetate, which is also a substrate for Slc5a8 but not an inhibitor of histone deacetylases, does not affect dendritic cell development, indicating the essential role of histone deacetylase inhibition in the process. The blockade of dendritic cell development by butyrate and propionate is associated with decreased expression of the transcription factors PU.1 and RelB. Butyrate also elicits its biologic effects through its ability to activate the G-protein-coupled receptor Gpr109a, but this mechanism is not involved in butyrate-induced blockade of dendritic cell development. The participation of Slc5a8 and the non-involvement of Gpr109a in butyrate effects have been substantiated using bone marrow cells obtained from Slc5a8−/− and Gpr109a−/− mice. These findings uncover an important mechanism underlying the anti-inflammatory functions of the bacterial fermentation products butyrate and propionate. PMID:20601425

  18. Structure Determination and Characterization of the Vitamin B[superscript 6] Degradative Enzyme (E)-2-(Acetamidomethylene)succinate Hydrolase

    SciTech Connect

    McCulloch, Kathryn M.; Mukherjee, Tathagata; Begley, Tadhg P.; Ealick, Steven E.

    2010-06-22

    The gene identification and kinetic characterization of (E)-2-(acetamidomethylene)succinate (E-2AMS) hydrolase has recently been described. This enzyme catalyzes the final reaction in the degradation of vitamin B{sub 6} and produces succinic semialdehyde, acetate, ammonia, and carbon dioxide from E-2AMS. The structure of E-2AMS hydrolase was determined to 2.3 {angstrom} using SAD phasing. E-2AMS hydrolase is a member of the {alpha}/{beta} hydrolase superfamily and utilizes a serine/histidine/aspartic acid catalytic triad. Mutation of either the nucleophilic serine or the aspartate resulted in inactive enzyme. Mutation of an additional serine residue in the active site causes the enzyme to be unstable and is likely structurally important. The structure also provides insight into the mechanism of hydrolysis of E-2AMS and identifies several potential catalytically important residues.

  19. Materials and methods for efficient succinate and malate production

    DOEpatents

    Jantama, Kaemwich; Haupt, Mark John; Zhang, Xueli; Moore, Jonathan C; Shanmugam, Keelnatham T; Ingram, Lonnie O'Neal

    2014-04-08

    Genetically engineered microorganisms have been constructed to produce succinate and malate in mineral salt media in pH-controlled batch fermentations without the addition of plasmids or foreign genes. The subject invention also provides methods of producing succinate and malate comprising the culture of genetically modified microorganisms.

  20. Transfer of propionate by rat small intestine in vitro

    PubMed Central

    Barry, R. J. C.; Jackson, M. J.; Smyth, D. H.

    1966-01-01

    1. The transfer of propionate by sacs of rat everted intestine has been investigated in relation to a number of physico-chemical factors which affect movement of weak electrolytes. 2. Neither the observed movement nor the distribution of propionate can be accounted for by the theory of non-ionic diffusion or by modifications of it, such as the microclimate hypothesis or partial permeability to ions. 3. It is not possible to account for the observed propionate movement by the electrical potential across the gut or by solvent drag. 4. The most satisfactory explanation for the observations is a transfer process in the gut for volatile fatty acids, and some features of this are discussed. PMID:5937409

  1. Metagenomics detects functional shifts in the bovine rumen microbiota in response to propionate intake

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Optimizing rumen microbial ecosystem output is essential towards improved ruminant agriculture. Ruminal infusion or intake of propionate, one of the predominant volatile fatty acids, has important implications for host physiology. However, how the rumen microbiota responds to propionate administrat...

  2. [On the nonexistence of propionic acid in various kinds of breeds (author's transl)].

    PubMed

    Lück, E; Oeser, H; Remmert, K H; Sabel, J

    1975-05-30

    Analyses of 45 samples of sour dough and various kinds of bread have shown that no appreciable amounts of propionic acid are formed during sour dough fermentation. Bread has no natural propionic acid content.

  3. 78 FR 70953 - Draft Guidance for Industry on Bioequivalence Recommendations for Fluticasone Propionate...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-27

    ... HUMAN SERVICES Food and Drug Administration Draft Guidance for Industry on Bioequivalence... Industry on Bioequivalence Recommendations for Fluticasone Propionate; Salmeterol Xinafoate'', published in... for Industry on Bioequivalence Recommendations for Fluticasone Propionate; Salmeterol...

  4. ARTICLES: Vapor-Liquid Equilibrium Data of Carbon Dioxide+Methyl Propionate and Carbon Dioxide+Propyl Propionate Systems

    NASA Astrophysics Data System (ADS)

    Xu, Wei; Xie, Chuan-xin; Li, Hong-ling; Tian, Yi-ling

    2010-06-01

    High-pressure vapor-liquid equilibrium data for the binary systems of methyl propionate+carbon dioxide and propyl propionate+carbon dioxide were measured at pressure from 1.00 MPa to 12.00 MPa and temperature in the range from 313 K to 373 K. Experimental results were correlated with the Peng-Robinson equation of state with the two-parameter van der Waals mixing rule. At the same time, the Henry's coefficient, partial molar enthalpy change and partial molar entropy change of CO2 during dissolution at different temperature were also calculated.

  5. Method to produce succinic acid from raw hydrolysates

    DOEpatents

    Donnelly, Mark I.; Sanville-Millard, Cynthia Y.; Nghiem, Nhuan Phu

    2004-06-01

    A method for producing succinic acid from industrial-grade hydrolysates is provided, comprising supplying an organism that contains mutations for the genes ptsG, pflB, and ldhA, allowing said organism to accumulate biomass, and allowing said organism to metabolize the hydrolysate. Also provided is a bacteria mutant characterized in that it produces succinic acid from substrate contained in industrial-grade hydrolysate in a ratio of between 0.6:1 and 1.3:1 succinic acid to substrate.

  6. Polarized electric field effects on the regulation of succinate dehydrogenase activity in amphibian muscle and liver: kinetic study.

    PubMed

    Subrahamanyam, K; Reddy, G R; Babu, G R; Chetty, C S

    1989-04-01

    Electropolarity treatment (0.8 V/DC/Cm) was given to the gastrocnemius muscle of Bufo melanostictus every day for 5 min. for 5 days, and kinetic study of succinate dehydrogenase (SDH) in muscle and liver was conducted with different effectors - sodium malonate, ethylene diamine tetra acetic acid (EDTA), calcium chloride (CACl2) and sodium citrate. Of the four modulators tested, the malonate and EDTA inhibited while sodium citrate and CACl2 activated the enzyme. The significance of the modulation in SDH activity to different extents was discussed.

  7. 21 CFR 522.842 - Estradiol benzoate and testosterone propionate.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Estradiol benzoate and testosterone propionate. 522.842 Section 522.842 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS IMPLANTATION OR INJECTABLE DOSAGE FORM...

  8. 21 CFR 522.842 - Estradiol benzoate and testosterone propionate.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Estradiol benzoate and testosterone propionate. 522.842 Section 522.842 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS IMPLANTATION OR INJECTABLE DOSAGE FORM...

  9. 21 CFR 522.842 - Estradiol benzoate and testosterone propionate.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Estradiol benzoate and testosterone propionate. 522.842 Section 522.842 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS IMPLANTATION OR INJECTABLE DOSAGE FORM...

  10. 21 CFR 522.842 - Estradiol benzoate and testosterone propionate.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Estradiol benzoate and testosterone propionate. 522.842 Section 522.842 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS IMPLANTATION OR INJECTABLE DOSAGE FORM...

  11. 21 CFR 522.842 - Estradiol benzoate and testosterone propionate.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Estradiol benzoate and testosterone propionate. 522.842 Section 522.842 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS IMPLANTATION OR INJECTABLE DOSAGE FORM...

  12. 2-(2-Methyl-4-chlorophenoxy)propionic acid (MCPP)

    Integrated Risk Information System (IRIS)

    2 - ( 2 - Methyl - 4 - chlorophenoxy ) propionic acid ( MCPP ) ; CASRN 93 - 65 - 2 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( H

  13. 40 CFR 180.325 - 2-(m-Chlorophenoxy) propionic acid; tolerances for residues.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false 2-(m-Chlorophenoxy) propionic acid... Tolerances § 180.325 2-(m-Chlorophenoxy) propionic acid; tolerances for residues. (a) General. A tolerance is established for negligible residues of the plant regulator 2-(m-chlorophenoxy) propionic acid from...

  14. 75 FR 78243 - Propionic Acid and Salts, Urea Sulfate, Methidathion, and Methyl Parathion; Registration Review...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-15

    ... AGENCY Propionic Acid and Salts, Urea Sulfate, Methidathion, and Methyl Parathion; Registration Review... pesticides propionic acid and salts, case no. 4078, urea sulfate, case no. 7213, methidathion, case no. 0034... pesticides in the table below--propionic acid and salts, case 4078, urea sulfate, case no. 7213,...

  15. In vitro evaluation of cashew nut shell liquid as a methane-inhibiting and propionate-enhancing agent for ruminants.

    PubMed

    Watanabe, Y; Suzuki, R; Koike, S; Nagashima, K; Mochizuki, M; Forster, R J; Kobayashi, Y

    2010-11-01

    Cashew nut shell liquid (CNSL) containing antibacterial phenolic compounds was evaluated for its potency as a feed additive for ruminants. In experiment 1, ruminal responses to CNSL supplementation were assessed using a batch culture system. Rumen fluid from cattle was diluted with artificial saliva and incubated for 18h in a batch culture with a mixed diet containing a 30:70 hay:concentrate diet to which raw or heated CNSL was added at a final concentration of 500 μg/mL. In experiment 2, a Rusitec, using rumen fluid from the same cattle, was operated over a period of 7 d during which only raw CNSL was tested at concentrations of 0, 50, 100, or 200 μg/mL, and variations in fermentation and bacterial population were assessed. In experiment 3, a pure culture study was conducted using selected bacteria to determine their susceptibility to CNSL. In experiment 1, methane production was inhibited by raw CNSL (56.9% inhibition) but not by heated CNSL. Total volatile fatty acid concentration was not affected, whereas increased concentrations of propionate and decreased concentrations of acetate and butyrate were observed using either raw or heated CNSL. These changes were more obvious when raw CNSL was tested. In experiment 2, raw CNSL inhibited methanogenesis and increased propionate production in a dose-dependent manner, showing maximum methane inhibition (70.1%) and propionate enhancement (44.4%) at 200 μg/mL supplementation. Raw CNSL increased total volatile fatty acid concentration and dry matter digestibility. Raw CNSL also appeared to induce a dramatic shift in the population of rumen microbiota, based on decreased protozoa numbers and changes in quantitative PCR assay values for representative bacterial species. In experiment 3, using pure cultures, raw CNSL prevented the growth of hydrogen-, formate-, and butyrate-producing rumen bacteria, but not the growth of bacteria involved in propionate production. Based on these data, raw CNSL, rich in the antibacterial

  16. Solubility parameters of hypromellose acetate succinate and plasticization in dry coating procedures.

    PubMed

    Klar, Fabian; Urbanetz, Nora Anne

    2016-10-01

    Solubility parameters of HPMCAS have not yet been investigated intensively. On this account, total and three-dimensional solubility parameters of HPMCAS were determined by using different experimental as well as computational methods. In addition, solubility properties of HPMCAS in a huge number of solvents were tested and a Teas plot for HPMCAS was created. The total solubility parameter of about 24 MPa(0.5) was confirmed by various procedures and compared with values of plasticizers. Twenty common pharmaceutical plasticizers were evaluated in terms of their suitability for supporting film formation of HPMCAS under dry coating conditions. Therefore, glass transition temperatures of mixtures of polymer and plasticizers were inspected and film formation of potential ones was further investigated in dry coating of pellets. Contact angles of plasticizers on HPMCAS were determined in order to give a hint of achievable coating efficiencies in dry coating, but none was found to spread on HPMCAS. A few common substances, e.g. dimethyl phthalate, glycerol monocaprylate, and polyethylene glycol 400, enabled plasticization of HPMCAS; however, only triethyl citrate and triacetin were found to be suitable for use in dry coating. Addition of acetylated monoglycerides to triacetin increased coating efficiency, which was likewise previously demonstrated for triethyl citrate.

  17. Experimental feed induction of ruminal lactic, propionic, or butyric acidosis in sheep.

    PubMed

    Lettat, A; Nozière, P; Silberberg, M; Morgavi, D P; Berger, C; Martin, C

    2010-09-01

    A study was conducted to determine the feasibility to induce rumen acidosis with propionate, butyrate, or lactate as the major fermentation end products. Three rumen-cannulated Texel wethers were used in a 3 x 3 Latin square design. Each period consisted of 11 d of adaptation where wethers were daily fed at 90% of ad libitum intake a hay and wheat-based concentrate diet (4:1 ratio on a DM basis) in 2 equal portions followed by 3 d of acidosis induction. During the challenge, the morning feeding was replaced by an intraruminal supply of wheat (readily fermentable starch), corn (slowly fermentable starch), or beet pulp (easily digestible fiber), dosed at 1.2% of BW. Ruminal liquid samples were taken daily 1 h before (-1) and 1, 3, 5, and 6 h after intraruminal feed supply to measure pH, VFA, and lactic acid concentration. The differences between treatments accentuated throughout the 3-d challenge, being maximal and significant on d 3. Indeed, 6 h after the third day of the challenge, mean ruminal pH was less for wheat (4.85) than for corn (5.61; P = 0.008) and beet pulp (6.09; P = 0.001), and total VFA tended to be less for wheat (48.7 mM) than for corn and beet pulp (84.7 mM on average; P = 0.08). At the same time, the proportion of acetate was greater for wheat than for corn (75.5 and 62.2%, respectively; P = 0.005) but did not differ from beet pulp challenge (69.0%). The proportion of propionate was greatest for beet pulp compared with corn and wheat (21.0, 17.3, and 12.1%, respectively; P = 0.03), whereas the butyrate proportion was greatest for corn, intermediate for wheat, and least for beet pulp (16.3, 10.8, and 8.3%, respectively; P = 0.05). Lactate concentration was greatest for wheat (45.5 mM) compared with corn and beet pulp (8.3 mM on average; P = 0.01). Under our experimental conditions, ruminal lactic acidosis was successfully induced by wheat, whereas butyric and propionic subacute ruminal acidosis were respectively provoked by corn and beet pulp. We

  18. Succinate Dehydrogenase Loss in Familial Paraganglioma: Biochemistry, Genetics, and Epigenetics

    PubMed Central

    Her, Yeng F.; Maher, L. James

    2015-01-01

    It is counterintuitive that metabolic defects reducing ATP production can cause, rather than protect from, cancer. Yet this is precisely the case for familial paraganglioma, a form of neuroendocrine malignancy caused by loss of succinate dehydrogenase in the tricarboxylic acid cycle. Here we review biochemical, genetic, and epigenetic considerations in succinate dehydrogenase loss and present leading models and mysteries associated with this fascinating and important tumor. PMID:26294907

  19. Inhibition of membrane-bound succinate dehydrogenase by fluorescamine.

    PubMed

    Jay, D; Jay, E G; Garcia, C

    1993-12-01

    Fluorescamine rapidly inactivated membrane-bound succinate dehydrogenase. The inhibition of the enzyme by this reagent was prevented by succinate and malonate, suggesting that the group modified by fluorescamine was located at the active site. The modification of the active site sulfhydryl group by 5,5'-dithiobis(2-nitrobenzoic acid) (DTNB) did not alter the inhibitory action of fluorescamine. However, the protective effect of malonate against fluorescamine inhibition was abolished in the enzyme modified at the thiol.

  20. Identification of Protein Succination as a Novel Modification of Tubulin

    PubMed Central

    Piroli, Gerardo G.; Manuel, Allison M.; Walla, Michael D.; Jepson, Matthew J.; Brock, Jonathan W.C.; Rajesh, Mathur P.; Tanis, Ross M.; Cotham, William E.; Frizzell, Norma

    2015-01-01

    Protein succination is a stable post-translational modification that occurs when fumarate reacts with cysteine residues to generate S-(2-succino)cysteine (2SC). We demonstrate that both alpha (α) and beta (β) tubulin are increasingly modified by succination in 3T3-L1 adipocytes and in the adipose tissue of db/db mice. Incubation of purified tubulin from porcine brain with fumarate (50 mM) or the pharmacological compound dimethylfumarate (DMF, 500 μM) inhibited polymerization up to 35% and 59%, respectively. Using mass spectrometry we identified Cys347α, Cys376α, Cys12β and Cys303β as sites of succination in porcine brain tubulin and the relative abundance of succination at these cysteines increased in association with fumarate concentration. The increase in succination after incubation with fumarate altered tubulin recognition by an anti-α-tubulin antibody. Succinated tubulin in adipocytes cultured in high glucose vs. normal glucose also had reduced reactivity with the anti-αtubulin antibody; suggesting that succination may interfere with tubulin:protein interactions. DMF reacted rapidly with 11 of the 20 cysteines in the αβ tubulin dimer, decreased the number of free sulfhydryls and inhibited the proliferation of 3T3-L1 fibroblasts. Our data suggests that inhibition of tubulin polymerization is an important, undocumented mechanism of action of DMF. Taken together, our results demonstrate that succination is a novel post-translational modification of tubulin and suggest that extensive modification by fumarate, either physiologically or pharmacologically, may alter microtubule dynamics. PMID:24909641

  1. Towards hyperpolarized 13C-succinate imaging of brain cancer

    NASA Astrophysics Data System (ADS)

    Bhattacharya, Pratip; Chekmenev, Eduard Y.; Perman, William H.; Harris, Kent C.; Lin, Alexander P.; Norton, Valerie A.; Tan, Chou T.; Ross, Brian D.; Weitekamp, Daniel P.

    2007-05-01

    We describe a novel 13C enriched precursor molecule, sodium 1- 13C acetylenedicarboxylate, which after hydrogenation by PASADENA (Parahydrogen and Synthesis Allows Dramatically Enhanced Nuclear Alignment) under controlled experimental conditions, becomes hyperpolarized 13C sodium succinate. Fast in vivo 3D FIESTA MR imaging demonstrated that, following carotid arterial injection, the hyperpolarized 13C-succinate appeared in the head and cerebral circulation of normal and tumor-bearing rats. At this time, no in vivo hyperpolarized signal has been localized to normal brain or brain tumor. On the other hand, ex vivo samples of brain harvested from rats bearing a 9L brain tumor, 1 h or more following in vivo carotid injection of hyperpolarized 13C sodium succinate, contained significant concentrations of the injected substrate, 13C sodium succinate, together with 13C maleate and succinate metabolites 1- 13C-glutamate, 5- 13C-glutamate, 1- 13C-glutamine and 5- 13C-glutamine. The 13C substrates and products were below the limits of NMR detection in ex vivo samples of normal brain consistent with an intact blood-brain barrier. These ex vivo results indicate that hyperpolarized 13C sodium succinate may become a useful tool for rapid in vivo identification of brain tumors, providing novel biomarkers in 13C MR spectral-spatial images.

  2. Succination of thiol groups in adipose tissue proteins in diabetes: succination inhibits polymerization and secretion of adiponectin.

    PubMed

    Frizzell, Norma; Rajesh, Mathur; Jepson, Matthew J; Nagai, Ryoji; Carson, James A; Thorpe, Suzanne R; Baynes, John W

    2009-09-18

    S-(2-Succinyl)cysteine (2SC) is formed by reaction of the Krebs cycle intermediate fumarate with cysteine residues in protein, a process termed succination of protein. Both fumarate and succination of proteins are increased in adipocytes cultured in high glucose medium (Nagai, R., Brock, J. W., Blatnik, M., Baatz, J. E., Bethard, J., Walla, M. D., Thorpe, S. R., Baynes, J. W., and Frizzell, N. (2007) J. Biol. Chem. 282, 34219-34228). We show here that succination of protein is also increased in epididymal, mesenteric, and subcutaneous adipose tissue of diabetic (db/db) mice and that adiponectin is a major target for succination in both adipocytes and adipose tissue. Cys-39, which is involved in cross-linking of adiponectin monomers to form trimers, was identified as a key site of succination of adiponectin in adipocytes. 2SC was detected on two of seven monomeric forms of adiponectin immunoprecipitated from adipocytes and epididymal adipose tissue. Based on densitometry, 2SC-adiponectin accounted for approximately 7 and 8% of total intracellular adiponectin in cells and tissue, respectively. 2SC was found only in the intracellular, monomeric forms of adiponectin and was not detectable in polymeric forms of adiponectin in cell culture medium or plasma. We conclude that succination of adiponectin blocks its incorporation into trimeric and higher molecular weight, secreted forms of adiponectin. We propose that succination of proteins is a biomarker of mitochondrial stress and accumulation of Krebs cycle intermediates in adipose tissue in diabetes and that succination of adiponectin may contribute to the decrease in plasma adiponectin in diabetes.

  3. Preparation of vinyl acetate

    DOEpatents

    Tustin, Gerald Charles; Zoeller, Joseph Robert; Depew, Leslie Sharon

    1998-01-01

    This invention pertains to the preparation of vinyl acetate by contacting a mixture of hydrogen and ketene with a heterogeneous catalyst containing a transition metal to produce acetaldehyde, which is then reacted with ketene in the presence of an acid catalyst to produce vinyl acetate.

  4. Preparation of vinyl acetate

    DOEpatents

    Tustin, G.C.; Zoeller, J.R.; Depew, L.S.

    1998-03-24

    This invention pertains to the preparation of vinyl acetate by contacting a mixture of hydrogen and ketene with a heterogeneous catalyst containing a transition metal to produce acetaldehyde, which is then reacted with ketene in the presence of an acid catalyst to produce vinyl acetate.

  5. Chloramphenicol succinate, a competitive substrate and inhibitor of succinate dehydrogenase: possible reason for its toxicity.

    PubMed

    Ambekar, C S; Lee, J S K; Cheung, B M Y; Chan, L C; Liang, R; Kumana, C R

    2004-08-01

    From our previous study [Eur. J. Clin. Pharmacol. 56 (2000) 405] we hypothesized that chloramphenicol succinate (CAPS) may be a competitive substrate for succinate dehydrogenase (SDH). It may be oxidized by SDH to release chloramphenicol (CAP), which may inhibit SDH by feed back mechanism. The present ex-vivo/in vitro study was aimed to investigate this possibility by using human tissues (bone marrow and liver samples) and animal tissues (rat liver and kidney). The effect of different SDH activators and specific inhibitors was studied on CAPS metabolism by SDH. The metabolites and reduction products were detected by using HPLC. In marrow samples, CAPS was slowly oxidized to form CAP. The formation of CAP (oxidation product) was enhanced by FAD and low malonate and inhibited by high malonate and 3-NPA. Similar results were obtained with mitochondria from human and rat tissues. These studies suggest that CAPS could be a competitive oxidative substrate and the metabolite CAP could be an inhibitor at the reduction site. Therefore, SDH could be a target molecule responsible for CAPS induced toxicity.

  6. Current advances in biological production of propionic acid.

    PubMed

    Eş, Ismail; Khaneghah, Amin Mousavi; Hashemi, Seyed Mohammad Bagher; Koubaa, Mohamed

    2017-02-01

    Propionic acid and its derivatives are considered "Generally Recognized As Safe" food additives and are generally used as an anti-microbial and anti-inflammatory agent, herbicide, and artificial flavor in diverse industrial applications. It is produced via biological pathways using Propionibacterium and some anaerobic bacteria. However, its commercial chemical synthesis from the petroleum-based feedstock is the conventional production process bit results in some environmental issues. Novel biological approaches using microorganisms and renewable biomass have attracted considerable recent attention due to economic advantages as well as great adaptation with the green technology. This review provides a comprehensive overview of important biotechnological aspects of propionic acid production using recent technologies such as employment of co-culture, genetic and metabolic engineering, immobilization technique and efficient bioreactor systems.

  7. Stability and interface properties of thin cellulose ester films adsorbed from acetone and ethyl acetate solutions.

    PubMed

    Amim, Jorge; Kosaka, Priscila M; Petri, Denise F S; Maia, Francisco C B; Miranda, Paulo B

    2009-04-15

    Stability and interface properties of cellulose acetate propionate (CAP) and cellulose acetate butyrate (CAB) films adsorbed from acetone or ethyl acetate onto Si wafers have been investigated by means of contact angle measurements and atomic force microscopy (AFM). Surface energy (gamma(S)(total)) values determined for CAP adsorbed from acetone are larger than those from ethyl acetate. In the case of CAB films adsorbed from ethyl acetate and acetone were similar. Dewetting was observed by AFM only for CAP films prepared from ethyl acetate. Positive values of effective Hamaker constant (A(eff)) were found only for CAP prepared from ethyl acetate, corroborating with dewetting phenomena observed by AFM. On the contrary, negative values of A(eff) were determined for CAP and CAB prepared from acetone and for CAB prepared from ethyl acetate, corroborating with experimental observations. Sum frequency generation (SFG) vibrational spectra indicated that CAP and CAB films prepared from ethyl acetate present more alkyl groups oriented perpendicularly to the polymer-air interface than those films prepared from acetone. Such preferential orientation corroborates with macroscopic contact angle measurements. Moreover, SFG spectra showed that acetone binds strongly to Si wafers, creating a new surface for CAP and CAB films.

  8. Nanofabrication in cellulose acetate.

    PubMed

    Zeng, Hongjun; Lajos, Robert; Metlushko, Vitali; Elzy, Ed; An, Se Young; Sautner, Joshua

    2009-03-07

    We have demonstrated nanofabrication with commercialized cellulose acetate. Cellulose acetate is used for bulk nanofabrication and surface nanofabrication. In bulk nanofabrication, cellulose acetate reacts with an e-beam and permanent patterns are formed in it instead of being transferred to other substrates. We have studied the nano relief modulation performance of cellulose acetate before and after development. The depth of the nanopatterns is magnified after development, and is varied by exposing dosage and line width of the pattern. The thinnest 65 nm wide line is achieved in the bulk fabrication. We also demonstrate a binary phase Fresnel lens array which is directly patterned in a cellulose acetate sheet. Because of its unique mechanical and optical properties, cellulose is a good candidate for a template material for soft imprinting lithography. In the surface nanofabrication, cellulose acetate thin film spin-coated on silicon wafers is employed as a new resist for e-beam lithography. We achieved 50 nm lines with 100 nm pitches, dots 50 nm in diameter, and single lines with the smallest width of 20 nm. As a new resist of e-beam lithography, cellulose acetate has high resolution comparable with conventional resists, while having several advantages such as low cost, long stock time and less harmfulness to human health.

  9. Succinate Dehydrogenase Gene Mutations in Cardiac Paragangliomas

    PubMed Central

    Martucci, Victoria L.; Emaminia, Abbas; del Rivero, Jaydira; Lechan, Ronald M.; Magoon, Bindiya T.; Galia, Analyza; Fojo, Tito; Leung, Steve; Lorusso, Roberto; Jimenez, Camilo; Shulkin, Barry L.; Audibert, Jennifer L.; Adams, Karen T.; Rosing, Douglas R.; Vaidya, Anand; Dluhy, Robert G.; Horvath, Keith A.; Pacak, Karel

    2015-01-01

    Pheochromocytomas and paragangliomas are chromaffin cell tumors arising from neuroendocrine cells. At least one third of paragangliomas are related to germline mutations in one of 17 genes. While these tumors can occur throughout the body, cardiac paragangliomas are very rare, accounting for less than 0.3% of mediastinal tumors. The purpose of this study was to determine the clinical characteristics of patients with cardiac paragangliomas, particularly focusing on their genetic backgrounds. A retrospective chart analysis of fifteen patients with cardiac paraganglioma was performed to determine clinical presentation, genetic background, diagnostic work-up, and outcomes. The average age at diagnosis was 41.9 years. Typical symptoms of paraganglioma (e.g., hypertension, sweating, palpitations, headache) were reported at initial presentation in 13 patients (86.7%); the remaining 2, as well as 4 symptomatic patients, initially presented with cardiac-specific symptoms (e.g., chest pain, dyspnea). Genetic testing was done in 13 cases (86.7%); 10 (76.9%) were positive for mutations in succinate dehydrogenase (SDHx) subunits B, C, or D. Thirteen cases (86.7%) underwent surgery to remove the paraganglioma with no intraoperative morbidity or mortality; one additional patient underwent surgical resection but experienced intraoperative complications after removal of the tumor due to comorbities and did not survive. SDHx mutations are known to be associated with mediastinal locations and malignant behavior of paragangliomas. In this report, we extend the locations of predominantly SDHx-related paragangliomas to cardiac tumors. In conclusion, cardiac paragangliomas are frequently associated with underlying SDHx germline mutations, suggesting a need for genetic testing of all patients with this rare tumor. PMID:25896150

  10. Set anode potentials affect the electron fluxes and microbial community structure in propionate-fed microbial electrolysis cells.

    PubMed

    Hari, Ananda Rao; Katuri, Krishna P; Logan, Bruce E; Saikaly, Pascal E

    2016-12-09

    Anode potential has been shown to be a critical factor in the rate of acetate removal in microbial electrolysis cells (MECs), but studies with fermentable substrates and set potentials are lacking. Here, we examined the impact of three different set anode potentials (SAPs; -0.25, 0, and 0.25 V vs. standard hydrogen electrode) on the electrochemical performance, electron flux to various sinks, and anodic microbial community structure in two-chambered MECs fed with propionate. Electrical current (49-71%) and CH4 (22.9-41%) were the largest electron sinks regardless of the potentials tested. Among the three SAPs tested, 0 V showed the highest electron flux to electrical current (71 ± 5%) and the lowest flux to CH4 (22.9 ± 1.2%). In contrast, the SAP of -0.25 V had the lowest electron flux to current (49 ± 6%) and the highest flux to CH4 (41.1 ± 2%). The most dominant genera detected on the anode of all three SAPs based on 16S rRNA gene sequencing were Geobacter, Smithella and Syntrophobacter, but their relative abundance varied among the tested SAPs. Microbial community analysis implies that complete degradation of propionate in all the tested SAPs was facilitated by syntrophic interactions between fermenters and Geobacter at the anode and ferementers and hydrogenotrophic methanogens in suspension.

  11. Set anode potentials affect the electron fluxes and microbial community structure in propionate-fed microbial electrolysis cells

    PubMed Central

    Hari, Ananda Rao; Katuri, Krishna P.; Logan, Bruce E.; Saikaly, Pascal E.

    2016-01-01

    Anode potential has been shown to be a critical factor in the rate of acetate removal in microbial electrolysis cells (MECs), but studies with fermentable substrates and set potentials are lacking. Here, we examined the impact of three different set anode potentials (SAPs; −0.25, 0, and 0.25 V vs. standard hydrogen electrode) on the electrochemical performance, electron flux to various sinks, and anodic microbial community structure in two-chambered MECs fed with propionate. Electrical current (49–71%) and CH4 (22.9–41%) were the largest electron sinks regardless of the potentials tested. Among the three SAPs tested, 0 V showed the highest electron flux to electrical current (71 ± 5%) and the lowest flux to CH4 (22.9 ± 1.2%). In contrast, the SAP of −0.25 V had the lowest electron flux to current (49 ± 6%) and the highest flux to CH4 (41.1 ± 2%). The most dominant genera detected on the anode of all three SAPs based on 16S rRNA gene sequencing were Geobacter, Smithella and Syntrophobacter, but their relative abundance varied among the tested SAPs. Microbial community analysis implies that complete degradation of propionate in all the tested SAPs was facilitated by syntrophic interactions between fermenters and Geobacter at the anode and ferementers and hydrogenotrophic methanogens in suspension. PMID:27934925

  12. [Malate oxidation by mitochondrial succinate:ubiquinone-reductase].

    PubMed

    Belikova, Iu O; Kotliar, A B

    1988-04-01

    Succinate:ubiquinone reductase was shown to catalyze the oxidation of L- and D-stereoisomers of malate by artificial electron acceptors and ubiquinone. The rate of malate oxidation by succinate:ubiquinone reductase is by two orders of magnitude lower than that for the natural substrate--succinate. The values of kinetic constants for the oxidation of D- and L-stereoisomers of malate are equal to: V infinity = 0.1 mumol/min/mg protein, Km = 2 mM and V infinity = 0.05 mumol/min/mg protein, Km = 2 mM, respectively. The malate dehydrogenase activity is fully inhibited by the inhibitors of the dicarboxylate-binding site of the enzyme, i.e., N-ethylmaleimide and malonate and is practically insensitive to carboxin, a specific inhibitor of the ubiquinone-binding center. The enol form of oxaloacetate was shown to be the product of malate oxidation by succinate:ubiquinone reductase. The kinetics of inhibition of the enzyme activity by the ketone and enol forms of oxaloacetate was studied. Both forms of oxaloacetate effectively inhibit the succinate:ubiquinone reductase reaction.

  13. In vivo bioavailability studies of sumatriptan succinate buccal tablets

    PubMed Central

    Shivanand, K; Raju, SA; Nizamuddin, S; Jayakar, B

    2011-01-01

    Back ground and the purpose of study Sumatriptan succinate is a Serotonin 5- HT1 receptor agonist, used in treatment of migraine. It is absorbed rapidly but incompletely when given orally and undergoes first-pass metabolism, resulting in a low absolute bioavailability of about 15%. The aim of this work was to design mucoadhesive bilayered buccal tablets of sumatriptan succinate to improve its bioavailability. Methods Mucoadhesive polymers carbopol 934 (Carbopol), HPMC K4M, HPMC K15M along with ethyl cellulose as an impermeable backing layer were used for the preparation of mucoadhesive bilayered tablets. In vivo bioavailability studies was also conducted in rabbits for optimized formulation using oral solution of sumatriptan succinate as standard. Results Bilayered buccal tablets (BBT) containing the mixture of Carbopol and HPMC K4M in the ratio 1:1 (T1) had the maximum percentage of in vitro drug release within 6 hrs. The optimized formulation (T1) followed non-Fickian release mechanism. The percentage relative bioavailability of sumatriptan succinate from selected bilayered buccal tablets (T1) was found to be 140.78%. Conclusions Bilayered buccal tablets of sumatriptan succinate was successfully prepared with improved bioavailability. PMID:22615661

  14. Effects of succinate on ground beef color and premature browning.

    PubMed

    Mancini, R A; Ramanathan, R; Suman, S P; Dady, G; Joseph, P

    2011-10-01

    The objective of this experiment was to determine the effects of succinate on raw and cooked ground beef color. Chubs (n=10) were divided in half and assigned to either succinate (final w/w concentration of 2.5%) or distilled water. Patties (n=14 per chub half) were assigned to initial day 0 color and each of 6 treatment combinations, created by crossing 3 packaging types (vacuum, high-oxygen/80% O(2), and PVC) with 2 storage times (days 1 and 3). After storage, patties were cooked to either 66 °C or 71 °C. Succinate increased (P<0.05) ground beef pH and metmyoglobin reducing activity but had no effect (P>0.05) on raw a* and chroma values. Moreover, succinate decreased (P<0.05) raw L* values, lipid oxidation, and premature browning for patties packaged in PVC and high-oxygen. Succinate may increase cooked patty redness via its influence on meat pH.

  15. Determination of drug-polymer binding constants by affinity capillary electrophoresis for aryl propionic acid derivatives and related compounds.

    PubMed

    Jia, Zhongjiang; Choi, Duk Soon; Chokshi, Hitesh

    2013-03-01

    The binding constants (K(b)s) of 17 aryl propionic acid derivatives (APADs) and related compounds with polyvinylpyrrolidone (PVP K30) and vinylpyrrolidone-vinyl acetate copolymer (Kollidon VA64) in aqueous media were determined by affinity capillary electrophoreses (ACE). The K(b)s of APAD to polymers increase with octanol-water partition coefficients of the compounds. Kollidon VA64 is a stronger binder than PVP K30 to APAD compounds. The K(b)s are greater at pH 4 than at pH 9. Both hydrophobic interaction and hydrogen bonding may be involved. However, hydrophobic interaction appears to be dominant. The ACE method is simple and fast, which could be used to study drug-polymer interaction in aqueous media.

  16. Identification of a novel acetate-utilizing bacterium belonging to Synergistes group 4 in anaerobic digester sludge.

    PubMed

    Ito, Tsukasa; Yoshiguchi, Kazumi; Ariesyady, Herto Dwi; Okabe, Satoshi

    2011-12-01

    Major acetate-utilizing bacterial and archaeal populations in methanogenic anaerobic digester sludge were identified and quantified by radioisotope- and stable-isotope-based functional analyses, microautoradiography-fluorescence in situ hybridization (MAR-FISH) and stable-isotope probing of 16S rRNA (RNA-SIP) that can directly link 16S rRNA phylogeny with in situ metabolic function. First, MAR-FISH with (14)C-acetate indicated the significant utilization of acetate by only two major groups, unidentified bacterial cells and Methanosaeta-like filamentous archaeal cells, in the digester sludge. To identify the acetate-utilizing unidentified bacteria, RNA-SIP was conducted with (13)C(6)-glucose and (13)C(3)-propionate as sole carbon source, which were followed by phylogenetic analysis of 16S rRNA. We found that bacteria belonging to Synergistes group 4 were commonly detected in both 16S rRNA clone libraries derived from the sludge incubated with (13)C-glucose and (13)C-propionate. To confirm that this bacterial group can utilize acetate, specific FISH probe targeting for Synergistes group 4 was newly designed and applied to the sludge incubated with (14)C-acetate for MAR-FISH. The MAR-FISH result showed that bacteria belonging to Synergistes group 4 significantly took up acetate and their active population size was comparable to that of Methanosaeta in this sludge. In addition, as bacteria belonging to Synergistes group 4 had high K(m) for acetate and maximum utilization rate, they are more competitive for acetate over Methanosaeta at high acetate concentrations (2.5-10  mM). To our knowledge, it is the first time to report the acetate-utilizing activity of uncultured bacteria belonging to Synergistes group 4 and its competitive significance to acetoclastic methanogen, Methanosaeta.

  17. Reversible interruption of gap junctional communication by testosterone propionate in cultured Sertoli cells and cardiac myocytes.

    PubMed

    Pluciennik, F; Verrecchia, F; Bastide, B; Hervé, J C; Joffre, M; Délèze, J

    1996-02-01

    A direct cell-to-cell exchange of ions and molecules occurs through specialized membrane channels built by the interaction of two half channels, termed connexons, contributed by each of the two adjacent cells. The electrical and diffusional couplings have been investigated by monitoring respectively the cell-to-cell conductance and the fluorescence recovery after photobleaching, in Sertoli and cardiac cells of young rat. In both cell types, a rapid impairment of the intercellular coupling has been observed in the presence of testosterone propionate. This interruption of the cell-to-cell communication through gap junction channels was dose-dependent, observed in the concentration range 1 to 25 microM and was progressively reversed after withdrawing the testosterone ester. Pretreatment with cyproterone acetate, an antiandrogen which blocks the nuclear testosterone receptor by binding, did not prevent the uncoupling action of the androgen ester. This observation, together with the rapid time course of the uncoupling and recoupling, and the rather high effective concentration (micromolar) of the steroid compound, suggests a nongenomic mechanism of action. The uncoupling concentrations were very similar to those of other steroid compounds known to interrupt gap junctional communication. The uncoupling could result from a direct interaction of the steroid with the proteolipidic structure of the membrane, that might alter the conformation of the gap junction channels and their functional state.

  18. Succinic acid production from sucrose by Actinobacillus succinogenes NJ113.

    PubMed

    Jiang, Min; Dai, Wenyu; Xi, Yonglan; Wu, Mingke; Kong, Xiangping; Ma, Jiangfeng; Zhang, Min; Chen, Kequan; Wei, Ping

    2014-02-01

    In this study, sucrose, a reproducible disaccharide extracted from plants, was used as the carbon source for the production of succinic acid by Actinobacillus succinogenes NJ113. During serum bottle fermentation, the succinic acid concentration reached 57.1g/L with a yield of 71.5%. Further analysis of the sucrose utilization pathways revealed that sucrose was transported and utilized via a sucrose phosphotransferase system, sucrose-6-phosphate hydrolase, and a fructose PTS. Compared to glucose utilization in single pathway, more pathways of A. succinogenes NJ113 are dependent on sucrose utilization. By changing the control strategy in a fed-batch culture to alleviate sucrose inhibition, 60.5g/L of succinic acid was accumulated with a yield of 82.9%, and the productivity increased by 35.2%, reaching 2.16g/L/h. Thus utilization of sucrose has considerable potential economics and environmental meaning.

  19. Improved biological phosphorus removal performance driven by the aerobic/extended-idle regime with propionate as the sole carbon source.

    PubMed

    Wang, Dongbo; Li, Xiaoming; Yang, Qi; Zheng, Wei; Wu, Yan; Zeng, Tianjing; Zeng, Guangming

    2012-08-01

    Our previous studies proved that biological phosphorus removal (BPR) could be achieved in an aerobic/extended-idle (AEI) process employing two typical substrates of glucose and acetate as the carbon sources. This paper further evaluated the feasibility of another important substrate, propionate, serving as the carbon source for BPR in the AEI process, and compared the BPR performance between the AEI and anaerobic/oxic (A/O) processes. Two sequencing batch reactors (SBRs) were operated, respectively, as the AEI and A/O regimes for BPR using propionate as the sole substrate. The results showed that the AEI-reactor removed 2.98 ± 0.04-4.06 ± 0.06 mg of phosphorus per g of total suspended solids during the course of the steady operational trial, and the phosphorus content of the dried sludge was reached 8.0 ± 0.4% after 56-day operation, demonstrating the good performance of phosphorus removal. Then, the efficiencies of BPR and the transformations of the intracellular storages were compared between two SBRs. It was observed that the phosphorus removal efficiency was maintained around 95% in the AEI-reactor, and about 83% in the A/O-reactor, although the latter showed much greater transformations of both polyhydroxyalkanoates and glycogen. The facts clearly showed that BPR could be enhanced by the AEI regime using propionate as the carbon source. Finally, the mechanisms for the propionate fed AEI-reactor improving BPR were investigated. It was found that the sludge cultured by the AEI regime had more polyphosphate containing cells than that by the A/O regime. Further investigation revealed that the residual nitrate generated in the last aerobic period was readily deteriorated BPR in the A/O-SBR, but a slight deterioration was observed in the AEI-SBR. Moreover, the lower glycogen transformation measured in the AEI-SBR indicated that the biomass cultured by the AEI regime contained less glycogen accumulating organisms activities than that by the A/O regime.

  20. Fragrance material review on α-methylbenzyl acetate.

    PubMed

    McGinty, D; Letizia, C S; Api, A M

    2012-09-01

    A toxicologic and dermatologic review of α-methylbenzyl acetate when used as a fragrance ingredient is presented. α-Methylbenzyl acetate is a member of the fragrance structural group Aryl Alkyl Alcohol Simple Acid Esters (AAASAE). The AAASAE fragrance ingredients are prepared by reacting an aryl alkyl alcohol with a simple carboxylic acid (a chain of 1-4 carbons) to generate formate, acetate, propionate, butyrate, isobutyrate and carbonate esters. This review contains a detailed summary of all available toxicology and dermatology papers that are related to this individual fragrance ingredient and is not intended as a stand-alone document. Available data for α-methylbenzyl acetate were evaluated, then summarized, and includes: physical properties, acute toxicity, skin irritation, mucous membrane (eye) irritation, skin sensitization, elicitation, and repeated dose data. A safety assessment of the entire AAASAE will be published simultaneously with this document. Please refer to Belsito et al. (2012) for an overall assessment of the safe use of this material and all AAASAE in fragrances.

  1. Ischaemic accumulation of succinate controls reperfusion injury through mitochondrial ROS

    PubMed Central

    Gaude, Edoardo; Aksentijević, Dunja; Sundier, Stephanie Y.; Robb, Ellen L.; Logan, Angela; Nadtochiy, Sergiy M.; Ord, Emily N. J.; Smith, Anthony C.; Eyassu, Filmon; Shirley, Rachel; Hu, Chou-Hui; Dare, Anna J.; James, Andrew M.; Rogatti, Sebastian; Hartley, Richard C.; Eaton, Simon; Costa, Ana S.H.; Brookes, Paul S.; Davidson, Sean M.; Duchen, Michael R.; Saeb-Parsy, Kourosh; Shattock, Michael J.; Robinson, Alan J.; Work, Lorraine M.; Frezza, Christian; Krieg, Thomas; Murphy, Michael P.

    2014-01-01

    Ischaemia-reperfusion (IR) injury occurs when blood supply to an organ is disrupted and then restored, and underlies many disorders, notably heart attack and stroke. While reperfusion of ischaemic tissue is essential for survival, it also initiates oxidative damage, cell death, and aberrant immune responses through generation of mitochondrial reactive oxygen species (ROS)1-5. Although mitochondrial ROS production in IR is established, it has generally been considered a non-specific response to reperfusion1,3. Here, we developed a comparative in vivo metabolomic analysis and unexpectedly identified widely conserved metabolic pathways responsible for mitochondrial ROS production during IR. We showed that selective accumulation of the citric acid cycle (CAC) intermediate succinate is a universal metabolic signature of ischaemia in a range of tissues and is responsible for mitochondrial ROS production during reperfusion. Ischaemic succinate accumulation arises from reversal of succinate dehydrogenase (SDH), which in turn is driven by fumarate overflow from purine nucleotide breakdown and partial reversal of the malate/aspartate shuttle. Upon reperfusion, the accumulated succinate is rapidly re-oxidised by SDH, driving extensive ROS generation by reverse electron transport (RET) at mitochondrial complex I. Decreasing ischaemic succinate accumulation by pharmacological inhibition is sufficient to ameliorate in vivo IR injury in murine models of heart attack and stroke. Thus, we have identified a conserved metabolic response of tissues to ischaemia and reperfusion that unifies many hitherto unconnected aspects of IR injury. Furthermore, these findings reveal a novel pathway for metabolic control of ROS production in vivo, while demonstrating that inhibition of ischaemic succinate accumulation and its oxidation upon subsequent reperfusion is a potential therapeutic target to decrease IR injury in a range of pathologies. PMID:25383517

  2. Succinate-dependent metabolism in Trypanosoma cruzi epimastigotes.

    PubMed

    Denicola-Seoane, A; Rubbo, H; Prodanov, E; Turrens, J F

    1992-08-01

    Trypanosoma cruzi epimastigotes permeabilized with digitonin (65 micrograms (mg protein)-1) to measure mitochondrial respiration were exposed to different substrates. Although none of the NADH-dependent substrates stimulated respiration, succinate supported not only oxygen consumption but also oxidative phosphorylation (respiratory control ratio of 1.9 +/- 0.3) indicating that the mitochondria were coupled. The rate of NADH-dependent oxygen consumption by membrane fractions (9.4 +/- 0.7 nmol min-1 (mg protein)-1) was reduced by 50% upon addition of catalase indicating that the electrons from NADH oxidation reduced oxygen to H2O2. NADH-dependent H2O2 production (16 +/- 1 nmol min-1 (mg protein)-1) was confirmed using cytochrome c peroxidase. This activity was inhibited by fumarate by 70%, suggesting a competition between fumarate and oxygen for the electrons from NADH, probably at the fumarate reductase level. The respiratory chain inhibitor antimycin blocked both respiration by intact cells and succinate-dependent cytochrome c by isolated membranes. No inhibition by antimycin was observed when NADH replaced succinate as an electron donor, indicating that the electrons from NADH oxidation reduced cytochrome c through a different route. Malonate blocked not only succinate-cytochrome c reductase and fumarate reductase, but also intact cell motility. These results suggest that succinate has a central role in the intermediate metabolism of i. cruzi, as it may be used for respiration or excreted to the extracellular space under anaerobic conditions. In addition, 2 potential sources of H2O2 were tentatively identified as: (a) the enzyme fumarate reductase; and (b) a succinate-dependent site, which may be the semiquinone form of Coenzyme Q9, as in mammalian mitochondria.

  3. Mass isotopomer study of anaplerosis from propionate in the perfused rat heart

    PubMed Central

    Kasumov, Takhar; Cendrowski, Andrea V.; David, France; Jobbins, Kathryn A.; Anderson, Vernon E.; Brunengraber, Henri

    2007-01-01

    Anaplerosis from propionate was investigated in rat hearts perfused with 0–2 mM [13C3]propionate and physiological concentrations of glucose, lactate and pyruvate. The data show that when the concentration of [13C3]propionate was raised from 0 to 2 mM, total anaplerosis increases from 5 to 16% of the turnover of citric acid cycle intermediates. Then, [13C3]propionate abolished anaplerosis from endogenous substrates, glucose, lactate and pyruvate. Also, while the contents of propionyl-CoA and methylmalonyl-CoA increased with [13C3]propionate concentration, the content of succinyl-CoA decreased, presumably via activation of succinyl-CoA hydrolysis by a decrease in free CoA. Under our conditions, [13C3]propionate was a purely anaplerotic substrate since there was no labeling of mitochondrial acetyl-CoA, reflected by the labeling of the acetyl moiety of citrate. PMID:17418801

  4. Mutant E. coli strain with increased succinic acid production

    DOEpatents

    Donnelly, Mark; Millard, Cynthia S.; Stols, Lucy

    2001-09-25

    A method for isolating succinic acid producing bacteria is provided comprising increasing the biomass of an organism which lacks the ability to catabolize pyruvate, and then subjecting the biomass to glucose-rich medium in an anaerobic environment to enable pyruvate-catabolizing mutants to grow. The invention also provides for a mutant that produces high amounts of succinic acid, which has been derived from a parent which lacked the genes for pyruvate formate lyase and lactate dehydrogenase, and which belongs to the E.coli Group of Bacteria.

  5. Mutant E. coli strain with increased succinic acid production

    DOEpatents

    Donnelly, M.; Millard, C.S.; Stols, L.

    1998-06-23

    A method for isolating succinic acid producing bacteria is provided comprising increasing the biomass of an organism which lacks the ability to catabolize pyruvate, and then subjecting the biomass to glucose-rich medium in an anaerobic environment to enable pyruvate-catabolizing mutants to grow. The invention also provides for a mutant that produces high amounts of succinic acid, which as been derived from a parent which lacked the genes for pyruvate formate lyase and lactate dehydrogenase, and which belongs to the E.coli Group of Bacteria. 2 figs.

  6. Mutant E. coli strain with increased succinic acid production

    DOEpatents

    Donnelly, Mark; Millard, Cynthia S.; Stols, Lucy

    2002-01-01

    A method for isolating succinic acid producing bacteria is provided comprising increasing the biomass of an organism which lacks the ability to catabolize pyruvate, and then subjecting the biomass to glucose-rich medium in an anaerobic environment to enable pyruvate-catabolizing mutants to grow. The invention also provides for a mutant that produces high amounts of succinic acid, which has been derived from a parent which lacked the genes for pyruvate formate lyase and lactate dehydrogenase, and which belongs to the E.coli Group of Bacteria.

  7. Mutant E. coli strain with increased succinic acid production

    DOEpatents

    Donnelly, Mark; Millard, Cynthia S.; Stols, Lucy

    1998-01-01

    A method for isolating succinic acid producing bacteria is provided comprising increasing the biomass of an organism which lacks the ability to catabolize pyruvate, and then subjecting the biomass to glucose-rich medium in an anaerobic environment to enable pyruvate-catabolizing mutants to grow. The invention also provides for a mutant that produces high amounts of succinic acid, which as been derived from a parent which lacked the genes for pyruvate formate lyase and lactate dehydrogenase, and which belongs to the E.coli Group of Bacteria.

  8. Propionate metabolism in the rat heart by 13C n.m.r. spectroscopy.

    PubMed Central

    Sherry, A D; Malloy, C R; Roby, R E; Rajagopal, A; Jeffrey, F M

    1988-01-01

    High-resolution 13C n.m.r. spectroscopy has been used to examine propionate metabolism in the perfused rat heart. A number of tricarboxylic acid (TCA) cycle intermediates are observable by 13C n.m.r. in hearts perfused with mixtures of pyruvate and propionate. When the enriched 13C-labelled nucleus originates with pyruvate, the resonances of the intermediates appear as multiplets due to formation of multiply-enriched 13C-labelled isotopomers, whereas when the 13C-labelled nucleus originates with propionate, these same intermediates appear as singlets in the 13C spectrum since entry of propionate into the TCA cycle occurs via succinyl-CoA. An analysis of the isotopomer populations in hearts perfused with [3-13C]pyruvate plus unlabelled propionate indicates that about 27% of the total pyruvate pool available to the heart is derived directly from unlabelled propionate. This was substantiated by perfusing a heart for 2 h with [3-13C]propionate as the only available exogenous substrate. Under these conditions, all of the propionate consumed by the heart, as measured by conventional chemical analysis, ultimately entered the oxidative pathway as [2-13C] or [3-13C]pyruvate. This is consistent with entry of propionate into the TCA cycle intermediate pools as succinyl-CoA and concomitant disposal of malate to pyruvate via the malic enzyme. 13C resonances arising from enriched methylmalonate and propionylcarnitine are also detected in hearts perfused with [3-13C] or [1-13C]propionate which suggests that 13C n.m.r. may be useful as a non-invasive probe in vivo of metabolic abnormalities involving the propionate pathway, such as methylmalonic aciduria or propionic acidaemia. PMID:3178775

  9. Temporal Integration in Nasal Lateralization of Homologous Propionates

    PubMed Central

    Wise, Paul M.; Toczydlowski, Sean E.; Zhao, Kai; Wysocki, Charles J.

    2009-01-01

    For nasal irritation from volatile chemicals, a version of Haber’s rule (k = CnT) can model the trade-off between concentration (C) and duration of exposure (T) to achieve a fixed sensory impact, e.g., threshold-level irritation or a fixed supra-threshold intensity. The term “k” is a constant. The exponent, n, represents how well the system integrates over time. An exponent of 1 indicates complete temporal integration: an x-fold increase in stimulus-duration exactly compensates for cutting concentration 1/x. An exponent greater than 1 indicates incomplete temporal integration: more than an x-fold increase in duration is needed. In a previous study of homologous alcohols, n varied systematically with number of methylene units: integration became more compete as the length of the carbon chain increased. To explore the generality of this finding, we tested homologous esters that differ in number of methylene units: n-ethyl propionate, n-propyl propionate, and n-butyl propionate. Nasal lateralization was used to measure irritation thresholds. Human subjects received a fixed concentration of a single compound within each experimenal session. Stimulus-duration was varied to find the briefest stimulus that caused lateralizable irritation. Concentration and compound varied across sessions. Consistent with results with n-alcohols, integration became more complete as the number of methylene units increased. Lipid solubility varies with chain-length; hence solubility in the nasal mucosa may play a role in the dynamics of irritation. Further, preliminary analyses suggest that, for data pooled across both chemical series, n varied systematically with molecular parameters related to solubility and diffusion. PMID:19555224

  10. Propionate induces mRNA expression of gluconeogenic genes in bovine calf hepatocytes.

    PubMed

    Zhang, Qian; Koser, Stephanie L; Donkin, Shawn S

    2016-05-01

    Hepatocytes monolayers from neonatal calves were used to determine the responses of the cytosolic phosphoenolpyruvate carboxykinase (PCK1) mRNA expression to propionate and direct hormonal cues including cyclic AMP (cAMP), dexamethasone, and insulin. The responses of other key gluconeogenic genes, including mitochondrial phosphoenolpyruvate carboxykinase (PCK2), pyruvate carboxylase (PC), and glucose-6-phosphotase (G6PC), were also measured. Expression of PCK1 was linearly induced with increasing propionate concentrations in media and 2.5 mM propionate increased PCK1 mRNA at 3 and 6h of incubation; however, the induction disappeared at 12 and 24 h. The induction of PCK1 mRNA by propionate was mimicked by 1 mM cAMP, or in combination with 5 µM dexamethasone, but not by dexamethasone alone. The induction of PCK1 mRNA by propionate or cAMP was eliminated by addition of 100 nM insulin. Additionally, expression of PCK2 and PC mRNA was also induced by propionate in a concentration-dependent manner. Consistent with PCK1, propionate-stimulated PCK2 and PC mRNA expression was inhibited by insulin. Expression of G6PC mRNA was neither affected by propionate nor cAMP, dexamethasone, insulin, or their combinations. These findings demonstrate that propionate can directly regulate its own metabolism in bovine calf hepatocytes through upregulation of PCK1, PCK2, and PC mRNA expression.

  11. Gas chromatographic determination of propionates as paranitrobenzyl ester in bakery products.

    PubMed

    Takatsuki, K; Sakai, K

    1982-07-01

    A procedure was developed to determine propionates used as mold inhibitors and preservatives in bakery products. Propionates were extracted from the sample with water alkalinized by potassium carbonate. Water was evaporated, and the residue was reacted with paranitrobenzyl bromide in dimethyl-formamide-water (90 + 10) at room temperature to convert propionates to paranitrobenzyl ester, which was determined with a gas chromatograph equipped with a flame ionization detector. Bakery products, such as bread, sponge cake, cookies, and biscuits, were analyzed by this procedure. Recoveries from samples fortified with propionates ranged from 94 to 101%, with a standard deviation of 3.32. The concentrations determined were 50 to 2500 micrograms/g sample.

  12. Microwave Spectra of Fluorinated Propionic Acids and Their Hydrates

    NASA Astrophysics Data System (ADS)

    Obenchain, Daniel A.; Grubbs, G. S. Grubbs, Ii; Novick, Stewart E.; Cooke, Stephen A.; Serrato, Agapito Serrato, Iii; Lin, Wei

    2013-06-01

    The microwave spectra of three fluorinated propionic acids, namely pentafluoropropionic acid, 2,2,3,3-tetrafluoropropionic acid, and 2,3,3,3-tetrafluoropropionic acid have been observed and assigned. The spectra of pentafluoropropionic acid and its monohydrate were reported in this meeting last year. The conformational analysis of 2,2,3,3-tetrafluoropropionic acid and 2,3,3,3-tetrafluoropropionic acid will be compared to that of pentafluoropropionic acid. The structures of the three monohydrates will be discussed in terms of hydrogen bonding.

  13. Development of indole-3-propionic acid (OXIGON) for Alzheimer's disease.

    PubMed

    Bendheim, Paul E; Poeggeler, Burkhard; Neria, Eyal; Ziv, Vivi; Pappolla, Miguel A; Chain, Daniel G

    2002-01-01

    The accumulation of amyloid-beta and concomitant oxidative stress are major pathogenic events in Alzheimer's disease. Indole-3-propionic acid (IPA, OXIGON) is a potent anti-oxidant devoid of pro-oxidant activity. IPA has been demonstrated to be an inhibitor of beta-amyloid fibril formation and to be a potent neuroprotectant against a variety of oxidotoxins. This review will summarize the known properties of IPA and outline the rationale behind its selection as a potential disease-modifying therapy for Alzheimer's disease.

  14. Growth and characterization of organic NLO material: clobetasol propionate.

    PubMed

    Purusothaman, R; Rajesh, P; Ramasamy, P

    2015-06-15

    Single crystals of clobetasol propionate (CP) have been grown by slow evaporation solution technique using mixed solvent of methanol-acetone. The grown crystals were subjected to single crystal X-ray diffraction analysis to confirm their lattice parameter and space group. The powder X-ray diffraction pattern of the grown CP has been indexed. Thermal analysis was performed to study the thermal stability of the grown crystals. Photoluminescence spectrum shows broad emission peak observed at 421 nm. Nonlinear optical studies were carried out for the grown crystal and second harmonic generation (SHG) efficiency was found in the crystal.

  15. Growth and characterization of organic NLO material: Clobetasol propionate

    NASA Astrophysics Data System (ADS)

    Purusothaman, R.; Rajesh, P.; Ramasamy, P.

    2015-06-01

    Single crystals of clobetasol propionate (CP) have been grown by slow evaporation solution technique using mixed solvent of methanol-acetone. The grown crystals were subjected to single crystal X-ray diffraction analysis to confirm their lattice parameter and space group. The powder X-ray diffraction pattern of the grown CP has been indexed. Thermal analysis was performed to study the thermal stability of the grown crystals. Photoluminescence spectrum shows broad emission peak observed at 421 nm. Nonlinear optical studies were carried out for the grown crystal and second harmonic generation (SHG) efficiency was found in the crystal.

  16. Succinic acid-producing biofilms of Actinobacillus succinogenes: reproducibility, stability and productivity.

    PubMed

    Maharaj, K; Bradfield, M F A; Nicol, W

    2014-09-01

    Continuous anaerobic fermentations were performed in a biofilm reactor packed with Poraver® beads. Dilution rates (D) varied between 0.054 and 0.72 h(-1), and D-glucose and CO2 gas were used as carbon substrates. Steady-state conditions were shown to be repeatable and independent of the operational history. Production stability was achieved over periods exceeding 80 h at values of D below 0.32 h(-1). In these situations, steady-state variation (expressed as fluctuations in NaOH neutralisation flow rates) exhibited a standard deviation of less than 5 % while no indication of biofilm deactivation was detected. The total biomass amount was found to be independent of the dilution rate with an average dry concentration of 23.8 ± 2.9 g L(-1) obtained for all runs. This suggests that the attachment area controls the extent of biofilm accumulation. Specific succinic acid (SA) productivities, based on the total biomass amount, exhibited a substantial decrease with decreasing D. An SA volumetric productivity of 10.8 g L(-1) h(-1) was obtained at D = 0.7 h(-1)-the highest value reported to date in Actinobacillus succinogenes fermentations. SA yields on glucose increased with decreasing D, with a yield of 0.90 ± 0.01 g g(-1) obtained at a D of 0.054 h(-1). Production of formic acid approached zero with decreasing D, while the succinic to acetic acid ratio increased with decreasing D, resulting in an increasing SA yield on glucose.

  17. Metabolism of 14C-labeled doxylamine succinate (Bendectin) in the rhesus monkey (Macaca mulatta).

    PubMed

    Slikker, W; Holder, C L; Lipe, G W; Korfmacher, W A; Thompson, H C; Bailey, J R

    1986-01-01

    The time-course of the metabolic fate of [14C]doxylamine was determined after the p.o. administration of 13 mg/kg doxylamine succinate as Bendectin plus [14C]doxylamine succinate to the rhesus monkey. Urine and plasma samples were analyzed by reversed-phase high performance liquid chromatography (HPLC), chemical derivatization, and mass spectrometry. The cumulative 48-hr urinary metabolic profile contained 81% of the administered radiolabeled dose and consisted of at least six radiolabeled peaks. They were peak 1: unknown polar metabolites (8% of dose); peak 2: 2-[1-phenyl-1-(2-pyridinyl)ethoxy] acetic acid, 1-[1-phenyl-1(2-pyridinyl)ethoxy] methanol, and another minor metabolite(s) (31%); peak 3: doxylamine-N-oxide (1%); peak 4a: N,N-didesmethyldoxylamine (17%); peak 4b: doxylamine (4%); and peak 5: N-desmethyldoxylamine (20%). The plasma metabolic profile was the same as the urinary profile except for the absence of doxylamine-N-oxide. The maximum plasma concentrations and elapsed time to attain these concentrations were as follows. Peak 1: 540 ng/mL, 4 hr; peak 2: 1700 ng/mL, 1 hr; peak 4a: 430 ng/mL, 4 hr; peak 4b: 930 ng/mL, 2 hr; and peak 5: 790 ng/mL, 2 hr. These data suggest that in the monkey, doxylamine metabolism follows at least four pathways: a minor pathway to the N-oxide; a minor pathway to unknown polar metabolites; a major pathway to mono- and didesmethyldoxylamine via successive N-demethylation; and a major pathway to side-chain cleavage products (peak 2) via direct side-chain oxidation and/or deamination.

  18. Metabolism of /sup 14/C-labeled doxylamine succinate (Bendectin) in the rhesus monkey (Macaca mulatta)

    SciTech Connect

    Slikker, W. Jr.; Holder, C.L.; Lipe, G.W.; Korfmacher, W.A.; Thompson, H.C. Jr.; Bailey, J.R.

    1986-05-01

    The time-course of the metabolic fate of (/sup 14/C)doxylamine was determined after the p.o. administration of 13 mg/kg doxylamine succinate as Bendectin plus (/sup 14/C)doxylamine succinate to the rhesus monkey. Urine and plasma samples were analyzed by reversed-phase high performance liquid chromatography (HPLC), chemical derivatization, and mass spectrometry. The cumulative 48-hr urinary metabolic profile contained 81% of the administered radiolabeled dose and consisted of at least six radiolabeled peaks. They were peak 1: unknown polar metabolites (8% of dose); peak 2: 2-(1-phenyl-1-(2-pyridinyl)ethoxy) acetic acid, 1-(1-phenyl-1(2-pyridinyl)ethoxy) methanol, and another minor metabolite(s) (31%); peak 3: doxylamine-N-oxide (1%); peak 4a: N,N-didesmethyldoxylamine (17%); peak 4b: doxylamine (4%); and peak 5: N-desmethyldoxylamine (20%). The plasma metabolic profile was the same as the urinary profile except for the absence of doxylamine-N-oxide. The maximum plasma concentrations and elapsed time to attain these concentrations were as follows. Peak 1: 540 ng/mL, 4 hr; peak 2: 1700 ng/mL, 1 hr; peak 4a: 430 ng/mL, 4 hr; peak 4b: 930 ng/mL, 2 hr; and peak 5: 790 ng/mL, 2 hr. These data suggest that in the monkey, doxylamine metabolism follows at least four pathways: a minor pathway to the N-oxide; a minor pathway to unknown polar metabolites; a major pathway to mono- and didesmethyldoxylamine via successive N-demethylation; and a major pathway to side-chain cleavage products (peak 2) via direct side-chain oxidation and/or deamination.

  19. 21 CFR 172.275 - Synthetic paraffin and succinic derivatives.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... acid derivatives of isopropyl alcohol, polyethylene glycol, and polypropylene glycol. It consists of a... anhydride isopropyl half ester, dialkyl succinic anhydride polyethylene glycol half ester, and dialkyl... carbon atoms and the polyethylene and polypropylene glycols have molecular weights of 600 and...

  20. 21 CFR 172.275 - Synthetic paraffin and succinic derivatives.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... acid derivatives of isopropyl alcohol, polyethylene glycol, and polypropylene glycol. It consists of a... anhydride isopropyl half ester, dialkyl succinic anhydride polyethylene glycol half ester, and dialkyl... carbon atoms and the polyethylene and polypropylene glycols have molecular weights of 600 and...

  1. 21 CFR 172.275 - Synthetic paraffin and succinic derivatives.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... acid derivatives of isopropyl alcohol, polyethylene glycol, and polypropylene glycol. It consists of a... anhydride isopropyl half ester, dialkyl succinic anhydride polyethylene glycol half ester, and dialkyl... carbon atoms and the polyethylene and polypropylene glycols have molecular weights of 600 and...

  2. 21 CFR 172.275 - Synthetic paraffin and succinic derivatives.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... acid derivatives of isopropyl alcohol, polyethylene glycol, and polypropylene glycol. It consists of a... anhydride isopropyl half ester, dialkyl succinic anhydride polyethylene glycol half ester, and dialkyl... carbon atoms and the polyethylene and polypropylene glycols have molecular weights of 600 and...

  3. 21 CFR 172.275 - Synthetic paraffin and succinic derivatives.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ..., polyethylene glycol, and polypropylene glycol. It consists of a mixture of the Fischer-Tropsch process paraffin... anhydride polyethylene glycol half ester, and dialkyl succinic anhydride polypropylene glycol half ester, where the alkane (alkyl) has a chain length of 30-70 carbon atoms and the polyethylene and...

  4. 21 CFR 522.784 - Doxylamine succinate injection.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Doxylamine succinate injection. 522.784 Section 522.784 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS IMPLANTATION OR INJECTABLE DOSAGE FORM NEW ANIMAL...

  5. 21 CFR 522.1884 - Prednisolone sodium succinate injection.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Prednisolone sodium succinate injection. 522.1884 Section 522.1884 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS IMPLANTATION OR INJECTABLE DOSAGE FORM NEW ANIMAL...

  6. 21 CFR 522.1884 - Prednisolone sodium succinate injection.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Prednisolone sodium succinate injection. 522.1884 Section 522.1884 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS IMPLANTATION OR INJECTABLE DOSAGE FORM NEW ANIMAL...

  7. 21 CFR 522.784 - Doxylamine succinate injection.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Doxylamine succinate injection. 522.784 Section 522.784 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS IMPLANTATION OR INJECTABLE DOSAGE FORM NEW ANIMAL...

  8. 21 CFR 522.784 - Doxylamine succinate injection.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Doxylamine succinate injection. 522.784 Section 522.784 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS IMPLANTATION OR INJECTABLE DOSAGE FORM NEW ANIMAL...

  9. 21 CFR 522.1884 - Prednisolone sodium succinate.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Prednisolone sodium succinate. 522.1884 Section 522.1884 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS IMPLANTATION OR INJECTABLE DOSAGE FORM NEW ANIMAL...

  10. Melatonin and succinate reduce rat liver mitochondrial dysfunction in diabetes.

    PubMed

    Zavodnik, I B; Lapshina, E A; Cheshchevik, V T; Dremza, I K; Kujawa, J; Zabrodskaya, S V; Reiter, R J

    2011-08-01

    Mitochondrial dysfunction and an increase in mitochondrial reactive oxygen species in response to hyperglycemia during diabetes lead to pathological consequences of hyperglycemia. The aim of the present work was to investigate the role of a specific functional damage in rat liver mitochondria during diabetes as well as to evaluate the possibility of metabolic and antioxidative correction of mitochondrial disorders by pharmacological doses of succinate and melatonin. In rat liver mitochondria, streptozotocin-induced diabetes was accompanied by marked impairments of metabolism: we observed a significant activation of α-ketoglutarate dehydrogenase (by 60%, p<0.05) and a damage of the respiratory function. In diabetic animals, melatonin (10 mg/kg b.w., 30 days) or succinate (50 mg/kg b.w., 30 days) reversed the oxygen consumption rate V(3) and the acceptor control ratio to those in nondiabetic animals. Melatonin enhanced the inhibited activity of catalase in the cytoplasm of liver cells and prevented mitochondrial glutathione-S-transferase inhibition while succinate administration prevented α-ketoglutarate dehydrogenase activation. The mitochondria dysfunction associated with diabetes was partially remedied by succinate or melatonin administration. Thus, these molecules may have benefits for the treatment of diabetes. The protective mechanism may be related to improvements in mitochondrial physiology and the antioxidative status of cells.

  11. 21 CFR 522.784 - Doxylamine succinate injection.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Doxylamine succinate injection. 522.784 Section 522.784 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS IMPLANTATION OR INJECTABLE DOSAGE FORM NEW ANIMAL...

  12. Isolation of mutants deficient in acetyl-CoA synthetase and a possible regulator of acetate induction in Aspergillus niger.

    PubMed

    Sealy-Lewis, H M; Fairhurst, V

    1998-07-01

    Acetate-non-utilizing mutants in Aspergillus niger were selected by resistance to 1.2% propionate in the presence of 0.1% glucose. Mutants showing normal morphology fell into two complementation groups. One class of mutant lacked acetyl-CoA synthetase but had high levels of isocitrate lyase, while the second class showed reduced levels of both acetyl-CoA synthetase and isocitrate lyase compared to the wild-type strain. By analogy with mutants selected by resistance to 1.2% propionate in Aspergillus nidulans, the properties of the mutants in A. niger suggest that the mutations are either in the structural gene for acetyl-CoA synthetase (acuA) or in a possible regulatory gene of acetate induction (acuB). A third class of mutant in a different complementation group was obtained which had abnormal morphology (yellow mycelium and few conidia); the specific lesion in these mutants has not been determined.

  13. Mechanistic Insights into the Catalytic Oxidation of Carboxylic Acids on Au/TiO2: Partial Oxidation of Propionic and Butyric Acid to Gold Ketenylidene through Unsaturated Acids

    DOE PAGES

    McEntee, Monica; Tang, Wenjie; Neurock, Matthew; ...

    2014-12-12

    Here, the partial oxidation of model C2–C4 (acetic, propionic, and butyric) carboxylic acids on Au/TiO2 catalysts consisting of Au particles ~3 nm in size was investigated using transmission infrared spectroscopy and density functional theory. All three acids readily undergo oxidative dehydrogenation on Au/TiO2. Propionic and butyric acid dehydrogenate at the C2–C3 positions, whereas acetic acid dehydrogenates at the C1–C2 position. The resulting acrylate and crotonate intermediates are subsequently oxidized to form β-keto acids that decarboxylate. All three acids form a gold ketenylidene intermediate, Au2C=C=O, along the way to their full oxidation to form CO2. Infrared measurements of Au2C=C=O formation asmore » a function of time provides a surface spectroscopic probe of the kinetics for the activation and oxidative dehydrogenation of the alkyl groups in the carboxylate intermediates that form.« less

  14. Effects of volatile fatty acids on propionate metabolism and gluconeogenesis in caprine hepatocytes

    SciTech Connect

    Aiello, R.J.; Armentano, L.E.

    1987-12-01

    Isolated caprine hepatocytes were incubated with fatty acids of various chain lengths. Short-chain fatty acids effects on rates of gluconeogenesis and oxidation from (2-/sup 14/C) propionate were determined. Additions of glucose (2.5 mM) had no effect on hepatic (2-/sup 14/C)-propionate metabolism in the presence and absence of amino acids. A complete mixture of amino acids increased label incorporation from (2-/sup 14/C) propionate into (/sup 14/C) glucose by 22%. Butyrate inhibited (2-/sup 14/C) propionate metabolism and increased the apparent Michaelis constant for (2-/sup 14/C) propionate incorporation into (/sup 14/C) glucose from 2.4 +/- 1.5 to 5.6 +/- .9 mM. Butyrate's effects on propionate were similar in the presence and absence of L-carnitine (1 mM). Isobutyrate, 2-methylbutyrate, and valerate (1.25 mM) had no effect on (/sup 14/C) glucose production but decreased /sup 14/CO/sub 2/ production to 57, 61, and 54% of the control (2-/sup 14/C) propionate (1.25 mM). This inhibition on /sup 14/CO/sub 2/ was not competitive. Isovalerate had no effect on either (2-/sup 14/C) propionate incorporation into glucose of CO/sub 2/. An increase in ratio of (/sup 14/C) glucose to /sup 14/CO/sub 2/ from (2-/sup 14/C)-propionate demonstrated that short-chain fatty acids other than butyrate do not inhibit gluconeogenesis from propionate. In addition, fatty acids that generate a net synthesis of intracellular oxaloacetate may partition propionate carbons toward gluconeogenic rather than oxidative pathways in goat hepatocytes.

  15. Effects of 2-(3-methyl-cinnamyl-hydrazono)-propionate on fatty acid and glucose oxidation in the isolated rat diaphragm using 14C-labelled substrates. Hydrazonopropionic acids, a new class of hypoglycaemic substances, VIII.

    PubMed

    Binder, L; Oellerich, M; Haeckel, R; Beneking, M

    1988-12-01

    The influence of 2-(3-methyl-cinnamyl-hydrazono)-propionate on the utilization of various substrates in isolated rat hemidiaphragms was investigated in comparison with other hypoglycaemic compounds. The effect of 2-(3-methyl-cinnamyl-hydrazono)-propionate was concentration-dependent. At a concentration of 0.5 mmol/l 2-(3-methyl-cinnamyl-hydrazono)-propionate, glucose utilization increased from 0.276 +/- 0.043 mumol.g-1.l-1 to 0.894 +/- 0.303 mumol.g-1.l-1 (p less than 0.05). Pyruvate and lactate utilization were stimulated to a lesser extent, while acetate utilization remained nearly constant. At a concentration of 2 mmol/l 2-(3-methyl-cinnamyl-hydrazono)-propionate, the oxidation of palmitate decreased from 0.214 +/- 0.017 mumol.g-1.l-1 to 0.060 +/- 0.005 mumol.g-1.l-1, while the oxidation of octanoate was not decreased. These findings point to a stimulation of the glycolytic flux by inhibition of long-chain fatty acid oxidation.

  16. Method for construction of bacterial strains with increased succinic acid production

    DOEpatents

    Donnelly, Mark I.; Sanville-Millard, Cynthia; Chatterjee, Ranjini

    2000-01-01

    A fermentation process for producing succinic acid is provided comprising selecting a bacterial strain that does not produce succinic acid in high yield, disrupting the normal regulation of sugar metabolism of said bacterial strain, and combining the mutant bacterial strain and selected sugar in anaerobic conditions to facilitate production of succinic acid. Also provided is a method for changing low yield succinic acid producing bacteria to high yield succinic acid producing bacteria comprising selecting a bacterial strain having a phosphotransferase system and altering the phosphotransferase system so as to allow the bacterial strain to simultaneously metabolize different sugars.

  17. 78 FR 55263 - Draft Guidance for Industry on Bioequivalence Recommendations for Fluticasone Propionate...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-09-10

    ... bioequivalence (BE) studies to support abbreviated new drug applications (ANDAs) for fluticasone propionate... New Hampshire Ave., Bldg. 51, rm. 2201, Silver Spring, MD 20993-0002. Send one self-addressed adhesive...; salmeterol xinafoate. Advair Diskus (fluticasone propionate; salmeterol xinafoate), new drug...

  18. Propionate induces cell swelling and K+ accumulation in shark rectal gland

    SciTech Connect

    Feldman, G.M.; Ziyadeh, F.N.; Mills, J.W.; Booz, G.W.; Kleinzeller, A. )

    1989-08-01

    Small organic anions have been reported to induce cell solute accumulation and swelling. To investigate the mechanism of swelling, we utilized preparations of rectal gland cells from Squalus acanthias incubated in medium containing propionate. Propionate causes cells to swell by diffusing across membranes in its nonionic form, acidifying cell contents, and activating the Na+-H+ antiporter. The Na+-H+ exchange process tends to correct intracellular pH (pHi), and thus it maintains a favorable gradient for propionic acid diffusion and allows propionate to accumulate. Activation of the Na+-H+ antiport also facilitates Na+ entry into the cell and Nai accumulation. At the same time Na+-K+-ATPase activity, unaffected by propionate, replaces Nai with Ki, whereas the K+ leak rate, decreased by propionate, allows Ki to accumulate. As judged by {sup 86}Rb+ efflux, the reduction in K+ leak was not due to propionate-induced cell acidification or reduction in Cli concentration. Despite inducing cell swelling, propionate did not disrupt cell structural elements and F actin distribution along cell membranes.

  19. Monitoring and control of the biogas process based on propionate concentration using online VFA measurement.

    PubMed

    Boe, Kanokwan; Steyer, Jean-Philippe; Angelidaki, Irini

    2008-01-01

    Simple logic control algorithms were tested for automatic control of a lab-scale CSTR manure digester. Using an online VFA monitoring system, propionate concentration in the reactor was used as parameter for control of the biogas process. The propionate concentration was kept below a threshold of 10 mM by manipulating the feed flow. Other online parameters such as pH, biogas production, total VFA, and other individual VFA were also measured to examine process performance. The experimental results showed that a simple logic control can successfully prevent the reactor from overload, but with fluctuations of the propionate level due to the nature of control approach. The fluctuation of propionate concentration could be reduced, by adding a lower feed flow limit into the control algorithm to prevent undershooting of propionate response. It was found that use of the biogas production as a main control parameter, rather than propionate can give a more stable process, since propionate was very persistent and only responded very slowly to the decrease of the feed flow which lead to high fluctuation of biogas production. Propionate, however, was still an excellent parameter to indicate process stress under gradual overload and thus recommended as an alarm in the control algorithm.

  20. 75 FR 51055 - Propionic Acid and Salts, and Urea Sulfate; Registration Review Proposed Decisions; Notice of...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-18

    ... AGENCY Propionic Acid and Salts, and Urea Sulfate; Registration Review Proposed Decisions; Notice of... availability of EPA's proposed registration review decisions for the pesticides propionic acid and salts, and... acid is a fungicide and bactericide that is used to control fungi and bacteria in stored hay and...

  1. Comparison of 5-Aminolevulinic Acid Photodynamic Therapy and Clobetasol Propionate in Treatment of Vulvar Lichen Sclerosus.

    PubMed

    Shi, Lei; Miao, Fei; Zhang, Ling-Lin; Zhang, Guo-Long; Wang, Pei-Ru; Ji, Jie; Wang, Xiao-Jie; Huang, Zheng; Wang, Hong-Wei; Wang, Xiu-Li

    2016-06-15

    The aim of this study was to evaluate the effectiveness of 5-aminolevulinic acid photodynamic therapy (ALA-PDT) for the treatment of vulvar lichen sclerosus (VLS) and compare its effectiveness with that of clobetasol propionate. Four sessions of topical photodynamic therapy (PDT) were administered at 2-week intervals (n = 20). Clobetasol propionate (0.05%) was used daily for 8 weeks (n = 20). The rate of complete response in the PDT group (14/20) was double that of the clobetasol propionate group (7/20) (p < 0.05, 2 = 4.912). Horizontal visual analogue scores indicated that PDT was more effective than clobetasol propionate. Pain intensity numeric rating scale values for PDT were between 3.05 and 4.45. One month after the final session of PDT, only one patient relapsed and all 7 patients in clobetasol propionate group relapsed. ALA-PDT is a well-tolerated and effective option for the treatment of VLS.

  2. Metabolic network rewiring of propionate flux compensates vitamin B12 deficiency in C. elegans.

    PubMed

    Watson, Emma; Olin-Sandoval, Viridiana; Hoy, Michael J; Li, Chi-Hua; Louisse, Timo; Yao, Victoria; Mori, Akihiro; Holdorf, Amy D; Troyanskaya, Olga G; Ralser, Markus; Walhout, Albertha Jm

    2016-07-06

    Metabolic network rewiring is the rerouting of metabolism through the use of alternate enzymes to adjust pathway flux and accomplish specific anabolic or catabolic objectives. Here, we report the first characterization of two parallel pathways for the breakdown of the short chain fatty acid propionate in Caenorhabditis elegans. Using genetic interaction mapping, gene co-expression analysis, pathway intermediate quantification and carbon tracing, we uncover a vitamin B12-independent propionate breakdown shunt that is transcriptionally activated on vitamin B12 deficient diets, or under genetic conditions mimicking the human diseases propionic- and methylmalonic acidemia, in which the canonical B12-dependent propionate breakdown pathway is blocked. Our study presents the first example of transcriptional vitamin-directed metabolic network rewiring to promote survival under vitamin deficiency. The ability to reroute propionate breakdown according to B12 availability may provide C. elegans with metabolic plasticity and thus a selective advantage on different diets in the wild.

  3. Pyruvate sparing by butyrate and propionate in proliferating colonic epithelium.

    PubMed

    Butler, R N; Stafford, I; Triantafillos, E; O'Dee, C D; Jarrett, I G; Fettman, M J; Roberts-Thomson, I C

    1990-01-01

    1. The effects of fasting and fasting followed by refeeding on the relative activities of the pyruvate dehydrogenase (PDH) complex and the tricarboxylic acid (TCA) cycle in isolated rat colonocytes were estimated by the rate of production of 14CO2 from [1-14C]pyruvate and [3-14C]pyruvate, respectively. 2. Decarboxylation of pyruvate by the PDH complex exceeded that by the TCA cycle in both fasted and fasted/refed colonocytes, was higher in distal than in proximal colon, and was stimulated by refeeding following a fast. 3. Oxidation of pyruvate by both the PDH complex and the TCA cycle was inhibited by butyrate. 4. Propionate alone had no effect, but synergized with butyrate to further reduce pyruvate decarboxylation by the TCA cycle. 5. Preferential utilization of butyrate by proliferating colonic epithelial cells is postulated to maximize the energy yield and spare pyruvate and its precursors for alternative synthetic roles necessary for active cell division.

  4. High-temperature unimolecular decomposition of ethyl propionate

    NASA Astrophysics Data System (ADS)

    Giri, Binod Raj; AlAbbad, Mohammed; Farooq, Aamir

    2016-11-01

    This work reports rate coefficients of the thermal unimolecular decomposition reaction of ethyl propionate (EP) behind reflected shock waves over the temperature range of 976-1300 K and pressures of 825-1875 Torr. The reaction progress was monitored by detecting C2H4 near 10.532 μm using CO2 gas laser absorption. In addition, G3//MP2/aug-cc-pVDZ and master equation calculations were performed to assess the pressure- and temperature-dependence of the reaction. Our calculations revealed that C2H4 elimination occurs via a six-centered retro-ene transition state. Our measured rate data are close to the high-pressure limit and showed no discernable temperature fall off.

  5. Propionic acid production by extractive fermentation. 1. Solvent considerations

    SciTech Connect

    Gu, Z.; Glatz, B.A.; Glatz, C.E.

    1998-02-20

    Solvent selection for extractive fermentation for propionic acid was conducted with three systems: Alamine{reg_sign} 304-1 (trilaurylamine) in 2-octanol, 1-dodecanol, and Witcohol{reg_sign} 85 NF (oleyl alcohol). Among them, the solvent containing 2-octanol exhibited the highest partition coefficient in acid extraction, but it was also toxic to propionibacteria. The most solvent-resistant strain among five strains of the microorganism was selected. Solvent toxicity was eliminated via two strategies: entrapment of dissolved toxic solvent in the culture growth medium with vegetable oils such as corn, olive, or soybean oils; or replacement of the toxic 2-octanol with nontoxic Witcohol 85 NF. The complete recovery of acids from the Alamine 304-1/Witcohol 85 NF was also realized with vacuum distillation.

  6. Propionic acid production by extractive fermentation. I. Solvent considerations.

    PubMed

    Gu, Z; Glatz, B A; Glatz, C E

    1998-02-20

    Solvent selection for extractive fermentation for propionic acid was conducted with three systems: Alamine 304-1 (trilaurylamine) in 2-octanol, 1-dodecanol, and Witcohol 85 NF (oleyl alcohol). Among them, the solvent containing 2-octanol exhibited the highest partition coefficient in acid extraction, but it was also toxic to propionibacteria. The most solvent-resistant strain among five strains of the microorganism was selected. Solvent toxicity was eliminated via two strategies: entrapment of dissolved toxic solvent in the culture growth medium with vegetable oils such as corn, olive, or soybean oils; or replacement of the toxic 2-octanol with nontoxic Witcohol 85 NF. The complete recovery of acids from the Alamine 304-1/Witcohol 85 NF was also realized with vacuum distillation.

  7. Pathway engineering of Propionibacterium jensenii for improved production of propionic acid

    PubMed Central

    Liu, Long; Guan, Ningzi; Zhu, Gexin; Li, Jianghua; Shin, Hyun-dong; Du, Guocheng; Chen, Jian

    2016-01-01

    Propionic acid (PA) is an important chemical building block widely used in the food, pharmaceutical, and chemical industries. In our previous study, a shuttle vector was developed as a useful tool for engineering Propionibacterium jensenii, and two key enzymes—glycerol dehydrogenase and malate dehydrogenase—were overexpressed to improve PA titer. Here, we aimed to improve PA production further via the pathway engineering of P. jensenii. First, the phosphoenolpyruvate carboxylase gene (ppc) from Klebsiella pneumoniae was overexpressed to access the one-step synthesis of oxaloacetate directly from phosphoenolpyruvate without pyruvate as intermediate. Next, genes encoding lactate dehydrogenase (ldh) and pyruvate oxidase (poxB) were deleted to block the synthesis of the by-products lactic acid and acetic acid, respectively. Overexpression of ppc and deleting ldh improved PA titer from 26.95 ± 1.21 g·L−1 to 33.21 ± 1.92 g·L−1 and 30.50 ± 1.63 g·L−1, whereas poxB deletion decreased it. The influence of this pathway engineering on gene transcription, enzyme expression, NADH/NAD+ ratio, and metabolite concentration was also investigated. Finally, PA production in P. jensenii with ppc overexpression as well as ldh deletion was investigated, which resulted in further increases in PA titer to 34.93 ± 2.99 g·L−1 in a fed-batch culture. PMID:26814976

  8. N-carbamylglutamate for neonatal hyperammonaemia in propionic acidaemia.

    PubMed

    Jones, S; Reed, C A B; Vijay, S; Walter, J H; Morris, A A M

    2008-12-01

    Hyperammonaemia is common in neonates with branched-chain organic acidaemias, primarily due to the inhibition of N-acetylglutamate (NAG) synthetase; NAG is an activator for carbamylphosphate synthetase I, the first enzyme of the urea cycle. N-Carbamylglutamate, a NAG analogue, has been reported to correct hyperammonaemia in neonates with organic acidaemias. It is, however, uncertain how the ammonia concentrations in these neonates would have progressed without the drug. We report a neonate with propionic acidaemia, whose plasma ammonia concentration responded dramatically to N-carbamylglutamate, having previously been over 950 μmol/L for 33 h. Our patient presented with poor feeding, hypoglycaemia, acidosis and hyperammonaemia (1044 μmol/L at 65 h of age). The patient was treated with intravenous glucose (12 mg/kg per min), insulin, sodium benzoate, sodium phenylbutyrate, carnitine and continuous veno-venous haemofiltration (CVVH). In spite of these measures, the plasma ammonia concentration remained above 950 μmol/L. After 30 h of CVVH, N-carbamylglutamate (250 mg/kg) was given through a nasogastric tube. Over the following 4 h, the plasma ammonia fell from 1410 μmol/L to 267 μmol/L. Despite stopping CVVH, the ammonia level dropped to 137 μmol/L over the next 2 h and it continued to fall while the intravenous drug doses were reduced. The patient was readmitted, aged 4 weeks, with hyperammonaemia (347 μmol/L) and again this responded to N-carbamylglutamate. In contrast, we report a previous patient with propionic acidaemia who showed no response to a lower dose of N-carbamylglutamate (25 mg/kg).

  9. [Comparative study of the influence of succinate-containing preparations on mitochondrial respiration in rat brain cells].

    PubMed

    Iasnetsov, V V; Prosvirova, E P; Tsublova, E G

    2012-01-01

    It has been established by polarographic measurements that preparations containing succinate, such as cytoflavin (0.85 mM succinate), mexidol, and amtizol succinate (at a concentration of 0.85 mM) but not reamberin (0.045 mM succinate), nearly equally (by 35-45%) increase oxygen consumption in rat brain mitochondria. On the other hand, malonate - inhibitor of the respiratory complex II (succinate dehydrogenase) of mitochondrial chain suppressed the stimulating effect of these drugs.

  10. The effect of delayed ensiling and application of a propionic acid-based additive on the fermentation of barley silage.

    PubMed

    Mills, J A; Kung, L

    2002-08-01

    Prolonged exposure to air can adversely affect the silage fermentation process. To investigate a possible method to overcome this problem, we determined if a buffered propionic acid-based additive, applied to chopped, whole-plant barley exposed to air before ensiling, would affect the subsequent fermentation. Wilted forage was chopped and treated with nothing, or with 0.1% (wt/wt wet forage) of a buffered propionic acid-based additive and ensiled immediately in quadruplicate 20-L laboratory silos. Portions of the chopped forage, untreated and treated, were left in loose piles in a barn for 24 h before ensiling. Another portion of the untreated silage exposed to air for 24 h was also treated with 0.1% of the additive just before ensiling. Prolonged exposure to air before ensiling increased the numbers of yeasts on forages by more than 1,000-fold. The concentrations of water-soluble carbohydrates decreased by more than 50%; the ammonia-N concentrations increased 40%, and pH increased by more than 1 unit as a result of exposure to air. These changes were less in forage that was treated with the additive at chopping. After 60 d, silages of forages that were exposed to air before ensiling had a higher pH, higher concentrations of ammonia-N and butyric acid, and lower concentrations of lactic and acetic acids than silages of forage that had been ensiled immediately after harvest. In situ DM digestibility was lowest in untreated silages that had been exposed to air before ensiling. In contrast, treatment with the additive, applied before or after exposure to air, prevented the reduction in in vitro digestion.

  11. A novel organic nonlinear optical crystal: Creatininium succinate

    NASA Astrophysics Data System (ADS)

    Thirumurugan, R.; Anitha, K.

    2015-06-01

    A novel organic material complex of creatininium succinate (CS) has been synthesized and single crystals were grown by the reaction of creatinine and succinic acid from aqueous solution by employing the technique of slow evaporation at room temperature. The structure of the grown crystal has been elucidated using single crystal X-ray diffraction analysis and the structure was refined by least-squares method to R = 0.027 for 1840 reflections. FT-IR spectral investigation has been carried out to identify the various functional groups in the title compound. UV-Vis transmission was carried out which shows the crystal has a good optical transmittance in the visible region with lower cutoff wavelength around 220 nm. Nonlinear optical property of the crystal was confirmed by Kurtz-Perry powder technique.

  12. Marked hypertriglyceridemia in a woman receiving metoprolol succinate.

    PubMed

    Kim, Yeunjung; Miller, Michael

    2014-01-01

    β-blockers are commonly used therapies after acute myocardial infarction and in the management of congestive heart failure and hypertension. We report a case of a middle-aged woman with a history of mild hypertension who was placed on metoprolol succinate. Before initiation of the β-blocker, her triglyceride level was in the borderline-high range (150-199 mg/dL). On treatment, her triglyceride levels exceeded 1000 mg/dL. She developed fatigue and mild abdominal discomfort but without biochemical evidence of pancreatitis. After discontinuation of metoprolol succinate, her triglyceride levels receded. This case illustrates an uncommon side effect with a very commonly used therapy in clinical practice. Clinicians should closely evaluate medications and/or other therapies in patients presenting with new-onset hypertriglyceridemia especially when levels are sufficiently elevated to pose increased risk of pancreatitis.

  13. A novel organic nonlinear optical crystal: Creatininium succinate

    SciTech Connect

    Thirumurugan, R.; Anitha, K.

    2015-06-24

    A novel organic material complex of creatininium succinate (CS) has been synthesized and single crystals were grown by the reaction of creatinine and succinic acid from aqueous solution by employing the technique of slow evaporation at room temperature. The structure of the grown crystal has been elucidated using single crystal X-ray diffraction analysis and the structure was refined by least-squares method to R = 0.027 for 1840 reflections. FT-IR spectral investigation has been carried out to identify the various functional groups in the title compound. UV–Vis transmission was carried out which shows the crystal has a good optical transmittance in the visible region with lower cutoff wavelength around 220 nm. Nonlinear optical property of the crystal was confirmed by Kurtz-Perry powder technique.

  14. Formulation and evaluation of sublingual tablets containing Sumatriptan succinate

    PubMed Central

    Prajapati, Shailesh T; Patel, Parth B; Patel, Chhagan N

    2012-01-01

    Objective: Sumatriptan succinate is a selective 5-hydroxytryptamine-1 receptor agonist effective in the acute treatment of migraine headaches, having low bioavailability of about 15% orally due to first-pass metabolism. The purpose of this research was to mask the intensely bitter taste of Sumatriptan succinate and to formulate fast-acting, taste-masked sublingual tablet formulation. Materials and Methods: Taste masking was performed by solid dispersion method with mannitol and ion exchange with Kyron T 114 because it releases the drug in salivary pH. The resultant batches were evaluated for in-vivo taste masking as well compatability study (Fourier transform infrared (FTIR) and differential scanning calorimetry (DSC)). For a better feel in the mouth, menthol and sweetener Na saccharine were added to the tablet formulation. The tablets were prepared by direct compression and evaluated for weight variation, thickness, friability, drug content, hardness, disintegration time, wetting time, in vitro drug release, and in vitro permeation study. Results and Discussion: Optimized batches disintegrated in vitro within 28-34 s. Maximum drug release could be achieved with in 10 min for the solid dispersion batches and 14-15 min for the ion-exchange batches with Kyron T 114. The optimized tablet formulation showed better taste and the formulated sublingual tablets may act as a potential alternate for the Sumatriptan succinate oral tablet. Conclusion: Sumatriptan succinate can be successfully taste-masked by both the solid dispersion method using mannitol by the melting method and Ion exchange resin with Kyron T114. It was also concluded that prepared formulation improve bioavailability by prevention of first pass metabolism. PMID:23373008

  15. [The research progress of succinic acid fermentation strains].

    PubMed

    Wang, Qing-Zhao; Zhao, Xue-Ming

    2007-07-01

    The potential of succinic acid as an important chemical intermediates had been realized and fermentation is one of the best ways to make it possible in economical aspect. Fermentation organism is the key part of the fermentation method. The updated research developments of fermentation organisms and the fermentation characteristics and problems of them were reviewed and analyzed in this paper. Finally,the development future of fermenation organism was forecasted.

  16. Focally perfused succinate potentiates brain metabolism in head injury patients.

    PubMed

    Jalloh, Ibrahim; Helmy, Adel; Howe, Duncan J; Shannon, Richard J; Grice, Peter; Mason, Andrew; Gallagher, Clare N; Stovell, Matthew G; van der Heide, Susan; Murphy, Michael P; Pickard, John D; Menon, David K; Carpenter, T Adrian; Hutchinson, Peter J; Carpenter, Keri Lh

    2016-01-01

    Following traumatic brain injury, complex cerebral energy perturbations occur. Correlating with unfavourable outcome, high brain extracellular lactate/pyruvate ratio suggests hypoxic metabolism and/or mitochondrial dysfunction. We investigated whether focal administration of succinate, a tricarboxylic acid cycle intermediate interacting directly with the mitochondrial electron transport chain, could improve cerebral metabolism. Microdialysis perfused disodium 2,3-(13)C2 succinate (12 mmol/L) for 24 h into nine sedated traumatic brain injury patients' brains, with simultaneous microdialysate collection for ISCUS analysis of energy metabolism biomarkers (nine patients) and nuclear magnetic resonance of (13)C-labelled metabolites (six patients). Metabolites 2,3-(13)C2 malate and 2,3-(13)C2 glutamine indicated tricarboxylic acid cycle metabolism, and 2,3-(13)C2 lactate suggested tricarboxylic acid cycle spinout of pyruvate (by malic enzyme or phosphoenolpyruvate carboxykinase and pyruvate kinase), then lactate dehydrogenase-mediated conversion to lactate. Versus baseline, succinate perfusion significantly decreased lactate/pyruvate ratio (p = 0.015), mean difference -12%, due to increased pyruvate concentration (+17%); lactate changed little (-3%); concentrations decreased for glutamate (-43%) (p = 0.018) and glucose (-15%) (p = 0.038). Lower lactate/pyruvate ratio suggests better redox status: cytosolic NADH recycled to NAD(+) by mitochondrial shuttles (malate-aspartate and/or glycerol 3-phosphate), diminishing lactate dehydrogenase-mediated pyruvate-to-lactate conversion, and lowering glutamate. Glucose decrease suggests improved utilisation. Direct tricarboxylic acid cycle supplementation with 2,3-(13)C2 succinate improved human traumatic brain injury brain chemistry, indicated by biomarkers and (13)C-labelling patterns in metabolites.

  17. Integration of succinic acid and ethanol production with potential application in a corn or barley biorefinery.

    PubMed

    Nghiem, Nhuan P; Hicks, Kevin B; Johnston, David B

    2010-11-01

    Production of succinic acid from glucose by Escherichia coli strain AFP184 was studied in a batch fermentor. The bases used for pH control included NaOH, KOH, NH(4)OH, and Na(2)CO(3). The yield of succinic acid without and with carbon dioxide supplied by an adjacent ethanol fermentor using either corn or barley as feedstock was examined. The carbon dioxide gas from the ethanol fermentor was sparged directly into the liquid media in the succinic acid fermentor without any pretreatment. Without the CO(2) supplement, the highest succinic acid yield was observed with Na(2)CO(3), followed by NH(4)OH, and lowest with the other two bases. When the CO(2) produced in the ethanol fermentation was sparged into the media in the succinic acid fermentor, no improvement of succinic acid yield was observed with Na(2)CO(3). However, several-fold increases in succinic acid yield were observed with the other bases, with NH(4)OH giving the highest yield increase. The yield of succinic acid with CO(2) supplement from the ethanol fermentor when NH(4)OH was used for pH control was equal to that obtained when Na(2)CO(3) was used, with or without CO(2) supplementation. The benefit of sparging CO(2) from ethanol fermentation on the yield of succinic acid demonstrated the feasibility of integration of succinic acid fermentation with ethanol fermentation in a biorefinery for production of fuels and industrial chemicals.

  18. Menaquinone-dependent succinate dehydrogenase of bacteria catalyzes reversed electron transport driven by the proton potential.

    PubMed

    Schirawski, J; Unden, G

    1998-10-01

    Succinate dehydrogenases from bacteria and archaea using menaquinone (MK) as an electron acceptor (succinate/menaquinone oxidoreductases) contain, or are predicted to contain, two heme-B groups in the membrane-anchoring protein(s), located close to opposite sides of the membrane. All succinate/ubiquinone oxidoreductases, however, contain only one heme-B molecule. In Bacillus subtilis and other bacteria that use MK as the respiratory quinone, the succinate oxidase activity (succinate-->O2), and the succinate/menaquinone oxidoreductase activity were specifically inhibited by uncoupler (CCCP, carbonyl cyanide m-chlorophenylhydrazone) or by agents dissipating the membrane potential (valinomycin). Other parts of the respiratory chains were not affected by the agents. Succinate oxidase or succinate/ubiquinone oxidoreductase from bacteria using ubiquinone as an acceptor were not inhibited. We propose that the endergonic electron transport from succinate (Eo' = +30 mV) to MK (Eo' approximately/= -80 mV) in succinate/menaquinone oxidoreductase includes a reversed electron transport across the cytoplasmic membrane from the inner (negative) to the outer (positive) side via the two heme-B groups. The reversed electron transport is driven by the proton or electrical potential, which provides the driving force for MK reduction.

  19. Global gene expression analysis of glucose overflow metabolism in Escherichia coli and reduction of aerobic acetate formation.

    PubMed

    Veit, Andrea; Polen, Tino; Wendisch, Volker F

    2007-02-01

    During aerobic growth on glucose, Escherichia coli produces acetate in the so-called overflow metabolism. DNA microarray analysis was used to determine the global gene expression patterns of chemostat cultivations of E. coli MG1655 that were characterized by different acetate formation rates during aerobic growth on glucose. A correlation analysis identified that expression of ten genes (sdhCDAB, sucB, sucC, acnB, lpdA, fumC and mdh) encoding the TCA cycle enzymes succinate dehydrogenase, alpha-ketoglutarate dehydrogenase, succinyl-CoA synthetase, aconitase, fumarase and malate dehydrogenase, respectively, and of the acs-yjcH-actP operon for acetate utilization correlated negatively with acetate formation. Relieving transcriptional control of the sdhCDAB-b0725-sucABCD operon by chromosomal promoter exchange mutagenesis yielded a strain with increased specific activities of the TCA cycle enzymes succinate dehydrogenase, alpha-ketoglutarate dehydrogenase and succinyl-CoA synthetase, which are encoded by this operon. The resulting strain produced less acetate and directed more carbon towards carbon dioxide formation than the parent strain MG1655 while maintaining high growth and glucose consumption rates.

  20. Atypical features of Thermus thermophilus succinate:quinone reductase.

    PubMed

    Kolaj-Robin, Olga; Noor, Mohamed R; O'Kane, Sarah R; Baymann, Frauke; Soulimane, Tewfik

    2013-01-01

    The Thermus thermophilus succinate:quinone reductase (SQR), serving as the respiratory complex II, has been homologously produced under the control of a constitutive promoter and subsequently purified. The detailed biochemical characterization of the resulting wild type (wt-rcII) and His-tagged (rcII-His(8)-SdhB and rcII-SdhB-His(6)) complex II variants showed the same properties as the native enzyme with respect to the subunit composition, redox cofactor content and sensitivity to the inhibitors malonate, oxaloacetate, 3-nitropropionic acid and nonyl-4-hydroxyquinoline-N-oxide (NQNO). The position of the His-tag determined whether the enzyme retained its native trimeric conformation or whether it was present in a monomeric form. Only the trimer exhibited positive cooperativity at high temperatures. The EPR signal of the [2Fe-2S] cluster was sensitive to the presence of substrate and showed an increased rhombicity in the presence of succinate in the native and in all recombinant forms of the enzyme. The detailed analysis of the shape of this signal as a function of pH, substrate concentration and in the presence of various inhibitors and quinones is presented, leading to a model for the molecular mechanism that underlies the influence of succinate on the rhombicity of the EPR signal of the proximal iron-sulfur cluster.

  1. Cell-permeable succinate prodrugs bypass mitochondrial complex I deficiency

    PubMed Central

    Ehinger, Johannes K.; Piel, Sarah; Ford, Rhonan; Karlsson, Michael; Sjövall, Fredrik; Frostner, Eleonor Åsander; Morota, Saori; Taylor, Robert W.; Turnbull, Doug M.; Cornell, Clive; Moss, Steven J.; Metzsch, Carsten; Hansson, Magnus J.; Fliri, Hans; Elmér, Eskil

    2016-01-01

    Mitochondrial complex I (CI) deficiency is the most prevalent defect in the respiratory chain in paediatric mitochondrial disease. This heterogeneous group of diseases includes serious or fatal neurological presentations such as Leigh syndrome and there are very limited evidence-based treatment options available. Here we describe that cell membrane-permeable prodrugs of the complex II substrate succinate increase ATP-linked mitochondrial respiration in CI-deficient human blood cells, fibroblasts and heart fibres. Lactate accumulation in platelets due to rotenone-induced CI inhibition is reversed and rotenone-induced increase in lactate:pyruvate ratio in white blood cells is alleviated. Metabolomic analyses demonstrate delivery and metabolism of [13C]succinate. In Leigh syndrome patient fibroblasts, with a recessive NDUFS2 mutation, respiration and spare respiratory capacity are increased by prodrug administration. We conclude that prodrug-delivered succinate bypasses CI and supports electron transport, membrane potential and ATP production. This strategy offers a potential future therapy for metabolic decompensation due to mitochondrial CI dysfunction. PMID:27502960

  2. Transcriptome analysis of acetic-acid-treated yeast cells identifies a large set of genes whose overexpression or deletion enhances acetic acid tolerance.

    PubMed

    Lee, Yeji; Nasution, Olviyani; Choi, Eunyong; Choi, In-Geol; Kim, Wankee; Choi, Wonja

    2015-08-01

    Acetic acid inhibits the metabolic activities of Saccharomyces cerevisiae. Therefore, a better understanding of how S. cerevisiae cells acquire the tolerance to acetic acid is of importance to develop robust yeast strains to be used in industry. To do this, we examined the transcriptional changes that occur at 12 h post-exposure to acetic acid, revealing that 56 and 58 genes were upregulated and downregulated, respectively. Functional categorization of them revealed that 22 protein synthesis genes and 14 stress response genes constituted the largest portion of the upregulated and downregulated genes, respectively. To evaluate the association of the regulated genes with acetic acid tolerance, 3 upregulated genes (DBP2, ASC1, and GND1) were selected among 34 non-protein synthesis genes, and 54 viable mutants individually deleted for the downregulated genes were retrieved from the non-essential haploid deletion library. Strains overexpressing ASC1 and GND1 displayed enhanced tolerance to acetic acid, whereas a strain overexpressing DBP2 was sensitive. Fifty of 54 deletion mutants displayed enhanced acetic acid tolerance. Three chosen deletion mutants (hsps82Δ, ato2Δ, and ssa3Δ) were also tolerant to benzoic acid but not propionic and sorbic acids. Moreover, all those five (two overexpressing and three deleted) strains were more efficient in proton efflux and lower in membrane permeability and internal hydrogen peroxide content than controls. Individually or in combination, those physiological changes are likely to contribute at least in part to enhanced acetic acid tolerance. Overall, information of our transcriptional profile was very useful to identify molecular factors associated with acetic acid tolerance.

  3. Tolerance to acetic acid is improved by mutations of the TATA-binding protein gene.

    PubMed

    An, Jieun; Kwon, Hyeji; Kim, Eunjung; Lee, Young Mi; Ko, Hyeok Jin; Park, Hongjae; Choi, In-Geol; Kim, Sooah; Kim, Kyoung Heon; Kim, Wankee; Choi, Wonja

    2015-03-01

    Screening a library of overexpressing mutant alleles of the TATA-binding gene SPT15 yielded two Saccharomyces cerevisiae strains (MRRC 3252 and 3253) with enhanced tolerance to acetic acid. They were also tolerant to propionic acid and hydrogen peroxide. Transcriptome profile analysis identified 58 upregulated genes and 106 downregulated genes in MRRC 3252. Stress- and protein synthesis-related transcription factors were predominantly enriched in the upregulated and downregulated genes respectively. Eight deletion mutants for some of the highly downregulated genes were acetic acid-tolerant. The level of intracellular reactive oxygen species was considerably lessened in MRRC 3252 and 3253 upon exposure to acetic acid. Metabolome profile analysis revealed that intracellular concentrations of 5 and 102 metabolites were increased and decreased, respectively, in MRRC 3252, featuring a large increase of urea and a significant decrease of amino acids. The dur1/2Δmutant, in which the urea degradation gene DUR1/2 is deleted, displayed enhanced tolerance to acetic acid. Enhanced tolerance to acetic acid was also observed on the medium containing a low concentration of amino acids. Taken together, this study identified two SPT15 alleles, nine gene deletions and low concentration of amino acids in the medium that confer enhanced tolerance to acetic acid.

  4. [Kinetic model of enhanced biological phosphorus removal with mixed acetic and propionic acids as carbon sources. (I): Model constitution].

    PubMed

    Zhang, Chao; Chen, Yin-Guang

    2013-03-01

    Based on activated sludge model No. 2 (ASM2), the anaerobic/aerobic kinetic model of phosphorus-accumulating organisms (PAO) was established with mixed short-chain fatty acids (SCFAs) as the base substance in enhanced biological phosphorus removal process. The characteristic of the PAO model was that the anaerobic metabolism rates of glycogen degradation, poly-beta-hydroxyalkanoates synthesis and polyphosphate hydrolysis were expressed by SCFAs uptake equation, and the effects of anaerobic maintenance on kinetics and stoichiometry were considered. The PAO kinetic model was composed of 3 soluble components, 4 particulate components and a pH parameter, which constituted the matrix of stoichiometric coefficients. On the basis of PAO model, the GAO kinetic model was established, which included 7 processes, and phosphorus content influenced the aerobic metabolism only.

  5. Acetate Kinase Isozymes Confer Robustness in Acetate Metabolism

    PubMed Central

    Chan, Siu Hung Joshua; Nørregaard, Lasse; Solem, Christian; Jensen, Peter Ruhdal

    2014-01-01

    Acetate kinase (ACK) (EC no: 2.7.2.1) interconverts acetyl-phosphate and acetate to either catabolize or synthesize acetyl-CoA dependent on the metabolic requirement. Among all ACK entries available in UniProt, we found that around 45% are multiple ACKs in some organisms including more than 300 species but surprisingly, little work has been done to clarify whether this has any significance. In an attempt to gain further insight we have studied the two ACKs (AckA1, AckA2) encoded by two neighboring genes conserved in Lactococcus lactis (L. lactis) by analyzing protein sequences, characterizing transcription structure, determining enzyme characteristics and effect on growth physiology. The results show that the two ACKs are most likely individually transcribed. AckA1 has a much higher turnover number and AckA2 has a much higher affinity for acetate in vitro. Consistently, growth experiments of mutant strains reveal that AckA1 has a higher capacity for acetate production which allows faster growth in an environment with high acetate concentration. Meanwhile, AckA2 is important for fast acetate-dependent growth at low concentration of acetate. The results demonstrate that the two ACKs have complementary physiological roles in L. lactis to maintain a robust acetate metabolism for fast growth at different extracellular acetate concentrations. The existence of ACK isozymes may reflect a common evolutionary strategy in bacteria in an environment with varying concentrations of acetate. PMID:24638105

  6. Short-term effect of acetate and ethanol on methane formation in biogas sludge.

    PubMed

    Refai, Sarah; Wassmann, Kati; Deppenmeier, Uwe

    2014-08-01

    Biochemical processes in biogas plants are still not fully understood. Especially, the identification of possible bottlenecks in the complex fermentation processes during biogas production might provide potential to increase the performance of biogas plants. To shed light on the question which group of organism constitutes the limiting factor in the anaerobic breakdown of organic material, biogas sludge from different mesophilic biogas plants was examined under various conditions. Therefore, biogas sludge was incubated and analyzed in anaerobic serum flasks under an atmosphere of N2/CO2. The batch reactors mirrored the conditions and the performance of the full-scale biogas plants and were suitable test systems for a period of 24 h. Methane production rates were compared after supplementation with substrates for syntrophic bacteria, such as butyrate, propionate, or ethanol, as well as with acetate and H2+CO2 as substrates for methanogenic archaea. Methane formation rates increased significantly by 35 to 126 % when sludge from different biogas plants was supplemented with acetate or ethanol. The stability of important process parameters such as concentration of volatile fatty acids and pH indicate that ethanol and acetate increase biogas formation without affecting normally occurring fermentation processes. In contrast to ethanol or acetate, other fermentation products such as propionate, butyrate, or H2 did not result in increased methane formation rates. These results provide evidence that aceticlastic methanogenesis and ethanol-oxidizing syntrophic bacteria are not the limiting factor during biogas formation, respectively, and that biogas plant optimization is possible with special focus on methanogenesis from acetate.

  7. Adipocyte protein modification by Krebs cycle intermediates and fumarate ester-derived succination.

    PubMed

    Manuel, Allison M; Frizzell, Norma

    2013-11-01

    Protein succination, the non-enzymatic modification of cysteine residues by fumarate, is distinguishable from succinylation, an enzymatic reaction forming an amide bond between lysine residues and succinyl-CoA. Treatment of adipocytes with 30 mM glucose significantly increases protein succination with only a small change in succinylation. Protein succination may be significantly increased intracellularly after treatment with fumaric acid esters, however, the ester must be removed by saponification to permit 2SC-antibody detection of the fumarate adduct.

  8. Vitamin E Succinate as an Adjuvant for Dendritic Cell Based Vaccines

    DTIC Science & Technology

    2006-07-01

    cancer cells by tocopherols and tocotrienols . Nutr Cancer, 33: 26-32, 1999. 33. Yu, W., Sanders, B. G., and Kline, K. RRR- alpha -tocopheryl succinate...DC vaccines with a chemotherapeutic drug, which may act as an adjuvant for DC vaccines. Vitamin E succinate or alpha tocopheryl succinate (α-TOS) is...residual disease setting, 3) identify the mechanism involved in mediating the anti-tumor response 15. SUBJECT TERMS Chemo-immunotherapy, alpha

  9. Sorption of chlorophenoxy propionic acids by organoclay complexes.

    PubMed

    Liao, Chiu-Jung; Chen, Chou-Pin; Wang, Ming-Kuang; Chiang, Po-Neng; Pai, Chuan-Wen

    2006-02-01

    The organoclays Wyoming montmorillonite (SWy-1, Mon), W. R. Grace vermiculite (Ver), and Tung-Wei (Tw) soil montmorillonite were prepared to sorb or remove chlorophenoxy propionic acids (CPA) pollutants such as 2,4-dichlorophenoxy acid (2,4-DP), 2,4,6-tri chlorophenoxy acid (2,4,6-TCP), and pentachlorophenoxy propionic acid (PCP). The objective of this study was to evaluate the behavior of organoclays that have sorbed three types of CPA and to assess the applicability to basaltic-developed iron-rich calcareous soil. This type of soil contains high amounts of montmorillonite. The mean-layer charge per formula unit of Mon, Ver, and Tw clays, characterized by the alkylammonium method, was 0.27, 0.70, and 0.52 mol(c)/O(10)(OH)(2), respectively. The sorption isotherms of 2,4-DP, 2,4,6-TCP, and PCP sorbed by hexadecyltrimethyl-ammonium (HDTMA organoclay, 150% cation-exchange capacity) were evaluated. The data on sorption of CPAs fit well with the Freundlich isotherm equation. In general, the sorption of three types of CPA by the organoclays showed a linear relationship, with a high correlation coefficient (r > 0.935). The K(f) value of PCP was the same as that of 2,4,6-TCP sorbed by the organoclays and was higher than that of 2,4-DP. However, the 1/n(f) values of the three CPAs sorbed by the organoclays did not show significant differences. In general, maximum CPA sorption occurred at a pH of approximately 3, but very significant differences were observed for the 2,4,6-TCP and PCP sorbed by the organoclays. However, there was no significant difference in pH for 2,4-DP sorption. This should be related to the solubility and pKa of each CPA. The experimental results showed that solubility of 2,4-DP, 2,4,6-TCP, and PCP is a function of pH, ionic strength, and temperature.

  10. Kallolide A acetate pyrazoline.

    PubMed

    Rodríguez-Escudero, Idaliz; Marrero, Jeffrey; Rodríguez, Abimael D

    2012-01-01

    IN THE CRYSTAL STRUCTURE OF KALLOLIDE A ACETATE PYRAZOLINE [SYSTEMATIC NAME: 7-methyl-16-oxo-4,10-bis-(prop-1-en-2-yl)-17,18-dioxa-14,15-diaza-tetra-cyclo-[9.4.2.1(6,9).0(1,12)]octa-deca-6,8,14-trien-5-yl acetate], C(23)H(28)N(2)O(5), there is a 12-member-ed carbon macrocyclic structure. In addition, there is a tris-ubstituted furan ring, an approximately planar γ-lactone ring [maximum deviation of 0.057 (3) Å] and a pyraz-oline ring, the latter in an envelope conformation. The pyrazoline and the γ-lactone rings are fused in a cis configuration. In the crystal, mol-ecules are linked by weak C-H⋯O inter-actions, forming a two-dimensional network parallel to (001). An intra-molecular C-H⋯O hydrogen bond is also present.

  11. Kallolide A acetate pyrazoline

    PubMed Central

    Rodríguez-Escudero, Idaliz; Marrero, Jeffrey; Rodríguez, Abimael D.

    2012-01-01

    In the crystal structure of kallolide A acetate pyrazoline [systematic name: 7-methyl-16-oxo-4,10-bis­(prop-1-en-2-yl)-17,18-dioxa-14,15-diaza­tetra­cyclo­[9.4.2.16,9.01,12]octa­deca-6,8,14-trien-5-yl acetate], C23H28N2O5, there is a 12-member­ed carbon macrocyclic structure. In addition, there is a tris­ubstituted furan ring, an approximately planar γ-lactone ring [maximum deviation of 0.057 (3) Å] and a pyraz­oline ring, the latter in an envelope conformation. The pyrazoline and the γ-lactone rings are fused in a cis configuration. In the crystal, mol­ecules are linked by weak C—H⋯O inter­actions, forming a two-dimensional network parallel to (001). An intra­molecular C—H⋯O hydrogen bond is also present. PMID:22259545

  12. Mechanisms leading to oligomers and SOA through aqueous photooxidation: insights from OH radical oxidation of acetic acid and methylglyoxal

    NASA Astrophysics Data System (ADS)

    Tan, Y.; Lim, Y. B.; Altieri, K. E.; Seitzinger, S. P.; Turpin, B. J.

    2012-01-01

    Previous experiments have demonstrated that the aqueous OH radical oxidation of methylglyoxal produces low volatility products including pyruvate, oxalate and oligomers. These products are found predominantly in the particle phase in the atmosphere, suggesting that methylglyoxal is a precursor of secondary organic aerosol (SOA). Acetic acid plays a central role in the aqueous oxidation of methylglyoxal and it is a ubiquitous product of gas phase photochemistry, making it a potential "aqueous" SOA precursor in its own right. However, the fate of acetic acid upon aqueous-phase oxidation is not well understood. In this research, acetic acid (20 μM-10 mM) was oxidized by OH radicals, and pyruvic acid and methylglyoxal experimental samples were analyzed using new analytical methods, in order to better understand the formation of SOA from acetic acid and methylglyoxal. Glyoxylic, glycolic, and oxalic acids formed from acetic acid and OH radicals. In contrast to the aqueous OH radical oxidation of methylglyoxal, the aqueous OH radical oxidation of acetic acid did not produce succinic acid and oligomers. This suggests that the methylgloxal-derived oligomers do not form through the acid catalyzed esterification pathway proposed previously. Using results from these experiments, radical mechanisms responsible for oligomer formation from methylglyoxal oxidation in clouds and wet aerosols are proposed. The importance of acetic acid/acetate as an SOA precursor is also discussed. We hypothesize that this and similar chemistry is central to the daytime formation of oligomers in wet aerosols.

  13. Regulation of fructose uptake and catabolism by succinate in Azospirillum brasilense.

    PubMed Central

    Mukherjee, A; Ghosh, S

    1987-01-01

    Fructose uptake and catabolism in Azospirillum brasilense is dependent on three fructose-inducible enzymes (fru-enzymes): (i) enzyme I and (ii) enzyme II of the phosphoenolpyruvate:fructose phosphotransferase system and (iii) 1-phosphofructokinase. In minimal medium containing 3.7 mM succinate and 22 mM fructose as sources of carbon, growth of A. brasilense was diauxic, succinate being utilized in the first phase of growth and fructose in the second phase with a lag period between the two growth phases. None of the fru-enzymes could be detected in cells grown with succinate as the sole source of carbon, but they were detectable toward the end of the first phase of diauxie. All the fru-enzymes were coinduced by fructose and coordinately repressed by succinate. Studies on the effect of succinate on differential rates of syntheses of the fru-enzymes revealed that their induced syntheses in fructose minimal medium were subject to transient as well as permanent (catabolite) repression by succinate. Succinate also caused a similar pattern of transient and permanent repression of the fructose transport system in A. brasilense. However, no inducer (fructose) exclusionlike effect was observed as there was no inhibition of fructose uptake in the presence of succinate with fructose-grown cells even when they were fully induced for succinate uptake activity. PMID:2957360

  14. Fermentative Succinate Production: An Emerging Technology to Replace the Traditional Petrochemical Processes

    PubMed Central

    Cao, Yujin; Zhang, Rubing; Sun, Chao; Cheng, Tao; Liu, Yuhua; Xian, Mo

    2013-01-01

    Succinate is a valuable platform chemical for multiple applications. Confronted with the exhaustion of fossil energy resources, fermentative succinate production from renewable biomass to replace the traditional petrochemical process is receiving an increasing amount of attention. During the past few years, the succinate-producing process using microbial fermentation has been made commercially available by the joint efforts of researchers in different fields. In this review, recent attempts and experiences devoted to reduce the production cost of biobased succinate are summarized, including strain improvement, fermentation engineering, and downstream processing. The key limitations and challenges faced in current microbial production systems are also proposed. PMID:24396827

  15. Effect of sodium succinate on gas exchange in rats with barbiturate-induced coma.

    PubMed

    Shefer, T V; Ivnitskii, Yu Yu; Malakhovskii, V N

    2003-04-01

    Injection of sodium succinate in doses of 5 or 10 mmol/kg (but not 1 mmol/kg) intensified oxygen consumption in rats with sodium thiopental-induced coma. Injection of SDH inhibitor (sodium malonate) inhibited gas exchange and abolished the effect of sodium succinate. The effect of succinate on rat survival was positive, while that of malonate was negative, but manifested only as a trend. The critical role of succinate oxidation in preventing lethal complications of barbiturate-induced coma is proved.

  16. The effects of buffered propionic acid-based additives alone or combined with microbial inoculation on the fermentation of high moisture corn and whole-crop barley.

    PubMed

    Kung, L; Myers, C L; Neylon, J M; Taylor, C C; Lazartic, J; Mills, J A; Whiter, A G

    2004-05-01

    Buffered propionic acid-based additives (BP) alone or in combination with a microbial inoculant containing lactic acid bacteria (MI) were mixed with ground, high moisture corn or whole-crop barley and ensiled in triplicate laboratory silos to investigate their effects on silage fermentation and aerobic stability. The inoculant and chemicals were applied separately for treatments that included both additives. The addition of MI alone had no effect on DM recovery, fermentation end products, or aerobic stability of high moisture corn. However, treatments with 0.1 and 0.2% BP (alone and the combination) had more than 10- and 100-fold fewer yeasts, respectively, and they also had greater concentrations of propionic acid than did untreated corn. Corn treated with only 0.1 (161 h) and 0.2% (218 h) BP tended to be more stable when exposed to air than untreated corn (122 h). Treatment with MI + 0.2% BP markedly improved the aerobic stability (>400 h) of high moisture corn. With whole-crop barley, the addition of MI alone, BP alone, and combinations of MI and BP prevented the production of butyric acid that was found in untreated silage (0.48%). All barley silages that had MI in their treatments underwent a more efficient fermentation than treatments without MI, as evident by a greater ratio of lactic:acetic acid and more DM recovery than in untreated silage. Increasing levels (0.1 to 0.2%) of BP added together with MI improved the aerobic stability of barley (190 and 429 h) over the addition of MI alone (50 h). These data show that buffered propionic acid-based products are compatible with microbial inoculants and, in some circumstances when used together, they can improve the fermentation and aerobic stability of silages.

  17. Clobetasol propionate spray 0.05% for the treatment of moderate to severe plaque psoriasis.

    PubMed

    Menter, Alan

    2012-02-01

    Clobetasol propionate is a super-high potent class 1 topical corticosteroid available in several formulations, including a spray formulation that is approved for use up to 4 weeks in patients aged 18 years and older with moderate to severe plaque psoriasis. The efficacy and safety of clobetasol propionate spray 0.05% has been extensively evaluated in clinical trials in more than 2200 patients with moderate to severe plaque psoriasis. This article reviews the efficacy, safety, and tolerability of clobetasol propionate spray 0.05%. Clobetasol propionate spray 0.05% is a topical product with a documented efficacy and safety profile with good acceptability in patients with moderate to severe plaque psoriasis.

  18. Impact of Propionic Acid on Liver Damage in Rats

    PubMed Central

    Al- Daihan, Sooad; Shafi Bhat, Ramesa

    2015-01-01

    Propionic acid (PA) is a short chain fatty acid, a common food preservative and metabolic end product of enteric bacteria in the gut. The present study was undertaken to investigate the effect of PA on liver injury in male rats. Male western albino rats were divided into two groups. The first group served as normal control, the second was treated with PA. The activities of serum hepatospecific markers such as aspartate transaminase, alanine transaminase, and alkaline phosphatase were estimated. Antioxidant status in liver tissues was estimated by determining the level of lipid peroxidation and activities of enzymatic and non-enzymatic antioxidants. Sodium and potassium levels were also measured in liver tissue. PA treatment caused significant changes in all hepatospecific markers. Biochemical analysis of liver homogenates from PA-treated rats showed an increase in oxidative stress markers like lipid peroxidation and lactate dehydrogenase, coupled with a decrease in glutathione, vitamin C and glutathione S- transferase. However, PA exposure caused no change in sodium and potassium levels in liver tissue. Our study demonstrated that PA persuade hepatic damage in rats. PMID:26629488

  19. High cell density propionic acid fermentation with an acid tolerant strain of Propionibacterium acidipropionici.

    PubMed

    Wang, Zhongqiang; Jin, Ying; Yang, Shang-Tian

    2015-03-01

    Propionic acid is an important chemical with wide applications and its production via fermentation is of great interest. However, economic production of bio-based propionic acid requires high product titer, yield, and productivity in the fermentation. A highly efficient and stable high cell density (HCD) fermentation process with cell recycle by centrifugation was developed for propionic acid production from glucose using an acid-tolerant strain of Propionibacterium acidipropionici, which had a higher specific growth rate, productivity, and acid tolerance compared to the wild type ATCC 4875. The sequential batch HCD fermentation at pH 6.5 produced propionic acid at a high titer of ∼40 g/L and productivity of 2.98 g/L h, with a yield of ∼0.44 g/g. The product yield increased to 0.53-0.62 g/g at a lower pH of 5.0-5.5, which, however, decreased the productivity to 1.28 g/L h. A higher final propionic acid titer of >55 g/L with a productivity of 2.23 g/L h was obtained in fed-batch HCD fermentation at pH 6.5. A 3-stage simulated fed-batch process in serum bottles produced 49.2 g/L propionic acid with a yield of 0.53 g/g and productivity of 0.66 g/L h. These productivities, yields and propionic acid titers were among the highest ever obtained in free-cell propionic acid fermentation.

  20. The Orphan G protein-coupled receptors GPR41 and GPR43 are activated by propionate and other short chain carboxylic acids.

    PubMed

    Brown, Andrew J; Goldsworthy, Susan M; Barnes, Ashley A; Eilert, Michelle M; Tcheang, Lili; Daniels, Dion; Muir, Alison I; Wigglesworth, Mark J; Kinghorn, Ian; Fraser, Neil J; Pike, Nicholas B; Strum, Jay C; Steplewski, Klaudia M; Murdock, Paul R; Holder, Julie C; Marshall, Fiona H; Szekeres, Philip G; Wilson, Shelagh; Ignar, Diane M; Foord, Steve M; Wise, Alan; Dowell, Simon J

    2003-03-28

    GPR41 and GPR43 are related members of a homologous family of orphan G protein-coupled receptors that are tandemly encoded at a single chromosomal locus in both humans and mice. We identified the acetate anion as an agonist of human GPR43 during routine ligand bank screening in yeast. This activity was confirmed after transient transfection of GPR43 into mammalian cells using Ca(2+) mobilization and [(35)S]guanosine 5'-O-(3-thiotriphosphate) binding assays and by coexpression with GIRK G protein-regulated potassium channels in Xenopus laevis oocytes. Other short chain carboxylic acid anions such as formate, propionate, butyrate, and pentanoate also had agonist activity. GPR41 is related to GPR43 (52% similarity; 43% identity) and was activated by similar ligands but with differing specificity for carbon chain length, with pentanoate being the most potent agonist. A third family member, GPR42, is most likely a recent gene duplication of GPR41 and may be a pseudogene. GPR41 was expressed primarily in adipose tissue, whereas the highest levels of GPR43 were found in immune cells. The identity of the cognate physiological ligands for these receptors is not clear, although propionate is known to occur in vivo at high concentrations under certain pathophysiological conditions.

  1. Effect of propionic acid on Campylobacter jejuni attached to chicken skin during refrigerated storage.

    PubMed

    González-Fandos, Elena; Maya, Naiara; Pérez-Arnedo, Iratxe

    2015-09-01

    The ability of propionic acid to reduce Campylobacter jejuni on chicken legs was evaluated. Chicken legs were inoculated with Campylobacter jejuni. After dipping legs in either water (control), 1% or 2% propionic acid solution (vol/vol), they were stored at 4ºC for 8 days. Changes in C. jejuni, psychrotrophs and Pseudomonas counts were evaluated. Washing in 2% propionic acid significantly reduced C. jejuni counts compared to control legs, with a decrease of about 1.62 log units after treatment. Treatment of chicken legs with 1 or 2% propionic acid significantly reduced numbers of psychrotrophs 1.01 and 1.08 log units and Pseudomonas counts 0.75 and 0.96 log units, respectively, compared to control legs. The reduction in psychrotrophs and Pseudomonas increased throughout storage. The highest reductions obtained for psychrotrophs and Pseudomonas counts in treated legs were reached at the end of storage, day 8, being 3.3 and 2.93 log units, respectively, compared to control legs. Propionic acid treatment was effective in reducing psychrotrophs and Pseudomonas counts on chicken legs throughout storage. It is concluded that propionic acid is effective for reducing C. jejuni populations in chicken.

  2. Mutagenicity testing of doxylamine succinate, an antinauseant drug.

    PubMed

    Müller, L; Korte, A; Madle, S

    1989-10-01

    Doxylamine succinate (DA), a compound which was formerly used as an antinauseant during pregnancy, showed no substantial mutagenicity in mouse embryos following transplacental exposure. A small dose-dependent induction of chromosomal aberrations was found in mouse embryos on day 11 of gestation. No induction of sister chromatid exchanges (SCE) was found in embryos on day 11 of gestation. A micronucleus test with fetal blood on day 17 of gestation was negative. Additionally, DA was negative in Chinese hamster bone marrow in vivo (micronuclei) and in human lymphocyte cultures in vitro (SCE).

  3. Radiation Protection by the Antioxidant Alpha-Tocopherol Succinate

    DTIC Science & Technology

    2005-01-01

    family of 8 tocols—4 each of α, β, γ, and δ tocopherols and tocotrienols (Figure 1). O CH3 R1 R2 HO CH3 CH3 CH3 CH3 CH3 R1 = R2 = CH3 d- alpha ...CH3 CH3 R1 = R2 = CH3 R1 = R2 = H R1 = H, R2 = CH3 R1 = CH3, R2 = H d- alpha - tocotrienol d-beta- tocotrienol d-gamma- tocotrienol d-delta- tocotrienol ...Radiation Protection by the Antioxidant Alpha -Tocopherol Succinate Vijay K. Singh1, V. Srinivasan1, Raymond Toles1, Patience Karikari1, Thomas

  4. Succinate causes α-SMA production through GPR91 activation in hepatic stellate cells.

    PubMed

    Li, Ying Hui; Woo, Sung Hoon; Choi, Dae Hee; Cho, Eun-Hee

    2015-08-07

    Succinate acts as an extracellular signaling molecule as well as an intermediate in the citric acid cycle. It binds to and activates its specific G protein-coupled receptor 91 (GPR91). GPR91 is present in hepatic stellate cells (HSCs), but its role in hepatic fibrogenesis remains unclear. Cultured HSCs treated with succinate showed increased protein expression of GPR91 and α-smooth muscle actin (α-SMA), markers of fibrogenic response. Succinate also increased mRNA expression of α-SMA, transforming growth factor β (TGF-β), and collagen type I. Transfection of siRNA against GPR91 abrogated succinate-induced increases in α-SMA expression. Malonate, an inhibitor of succinate dehydrogenase (SDH), increased succinate levels in cultured HSCs and increased GPR91 and α-SMA expression. Feeding mice a methionine- and choline-deficient (MCD) diet is a widely used technique to create an animal model of nonalcoholic steatohepatitis (NASH). HSCs cultured in MCD media showed significantly decreased SDH activity and increased succinate concentration and GPR91 and α-SMA expression. Similarly, palmitate treatment significantly decreased SDH activity and increased GPR91 and α-SMA expression. Finally, C57BL6/J mice fed the MCD diet had elevated succinate levels in their plasma. The MCD diet also decreased SDH activity, increased succinate concentration, and increased GPR91 and α-SMA expression in isolated HSCs. Collectively, our results show that succinate plays an important role in HSC activation through GPR91 induction, and suggest that succinate and GPR91 may represent new therapeutic targets for modulating hepatic fibrosis.

  5. Influence of 2(3-methyl-cinnamyl-hydrazono)-propionate on glucose and palmitate oxidation in human mononuclear leukocytes. Hydrazonopropionic acids, a new class of hypoglycaemic substances, VII.

    PubMed

    Haeckel, R; Fink, P C; Oellerich, M

    1987-09-01

    2-(3-Methyl-cinnamyl-hydrozono)-propionate stimulated glucose oxidation in human mononuclear leukocytes and the stimulation was similar to that by concanavalin A. Both substances must affect glucose metabolism at two sites, the first site being before the pyruvate dehydrogenase step because of the increase of lactate plus pyruvate concentration. The second site is related to pyruvate oxidation. The hydrazone inhibited the conversion of plamitate to CO2. This effect could have caused an activation of the pyruvate dehydrogenase complex, resulting from a decrease acetyl-CoA/CoA ratio. Concanavalin A did not influence fatty acid oxidation. Both substances did not affect the CO2 formation from acetate. Mononuclear leukocytes appear to be a suitable model for the investigation of the influence of hypoglycaemic substances on glucose and fatty acid metabolism in living human cells.

  6. Non-isothermal crystallization kinetics and characterization of biodegradable poly(butylene succinate-co-neopentyl glycol succinate) copolyesters.

    PubMed

    Xie, Wen-Jie; Zhou, Xiao-Ming

    2015-01-01

    Both biodegradable aliphatic neat poly(butylene succinate) (PBS) and poly(butylene succinate-co-neopentyl glycol succinate) (P(BS-co-NPGS)) copolyesters with different 1,4-butanediol/neopentyl glycol ratios were synthesized through a two-step process of transesterification and polycondensation using stannous chloride and 4-Methylbenzenesulfonic acid as the co-catalysts. The structure, non-isothermal crystallization behavior, crystalline morphology and crystal structure of neat PBS and P(BS-co-NPGS) copolyesters were characterized by (1)H NMR, differential scanning calorimetry (DSC), polarized optical microscope (POM) and wide angle X-ray diffraction (WAXD), respectively. The Avrami equation modified by Jeziorny and Mo's method was employed to describe the non-isothermal crystallization kinetics of the neat PBS and its copolyesters. The modified Avrami equation could adequately describe the primary stage of non-isothermal crystallization kinetics of the neat PBS and its copolyesters. Mo's method provided a fairly satisfactory description of the non-isothermal crystallization of neat PBS and its copolyesters. Interestingly, the values of 1/t1/2, Zc and F(T) obtained by the modified Avrami equation and Mo's method analysis indicated that the crystallization rate increased first and then decreased with an increase of NPGS content compared that of neat PBS, whereas the crystallization mechanism almost kept unchanged. The results of tensile testing showed that the ductility of PBS was largely improved by incorporating NPGS units. The elongation at break increased remarkably with increasing NPGS content. In particular, the sample with 20% NPGS content showed around 548% elongation at break.

  7. Use of Dialysis and Liquid-Liquid Extraction for the Determination of Propionic Acid by Gas Chromatography.

    PubMed

    Sasaki, Takahiro; Tahara, Shoichi; Yamajima, Yukiko; Miyakawa, Hiroyuki; Uematsu, Yoko; Monma, Kimio

    2016-01-01

    A simple and efficient method for the determination of propionic acid (PA) in foods was developed. The sample was cleaned up by dialysis, and PA in the resulting solution was extracted into ethyl acetate for GC analysis. Sodium sulfate was used as a salting-out agent in the extraction process, and GC-FID and GC-MS were successfully applied to the determination and confirmation of PA, respectively. The recoveries were in the range of 98.9-104.4% at the addition level of 0.2 g/kg from 6 foods, bread, cake, cheese, worcester sauce, vinegar-pickles and yogurt. To evaluate the performance of the developed method, recoveries from bread, cake and cheese were compared with those of the notified method at the maximal allowable addition level of PA as a preservative for each food. Recoveries of 98.2-99.5% for the developed method and 91.2-92.0% for the notified method were obtained. The analytical limit was 0.1 g/kg in samples for both determination and confirmation.

  8. Butyrate production from oligofructose fermentation by the human faecal flora: what is the contribution of extracellular acetate and lactate?

    PubMed

    Morrison, Douglas J; Mackay, William G; Edwards, Christine A; Preston, Tom; Dodson, Brian; Weaver, Lawrence T

    2006-09-01

    Butyrate is an important substrate for maintenance of colonic health and oligofructose fermentation by human faecal bacteria can increase butyrate production in vitro. However, oligofructose appears to be fermented by mainly acetate and lactate-producing bacteria rather than butyrate-producing bacteria. Isotope labelling studies using [U-(13)C(6)]glucose were used to show that (13)C(2) and (13)C(4) were the major labelled butyrate species produced from glucose fermentation, via [(13)C(2)]acetate-acetyl CoA as intermediate. Bacterial interconversion reactions were quantified and acetate conversion to butyrate and lactate conversion to acetate, propionate and butyrate were observed. Addition of oligofructose to faecal batch cultures significantly increased butyrate production. Of the newly synthesised butyrate from oligofructose fermentation, 80 % was derived from interconversion of extracellular acetate and lactate, with acetate being quantitatively more significant. Carbohydrates, such as oligofructose, have prebiotic properties. In addition, oligofructose selectively stimulates the bacterial conversion of acetate and lactate to butyrate. Carbohydrates with similar properties represent a refinement of the prebiotic definition, termed butyrogenic prebiotics, because of their additional functionality.

  9. Interaction of propionate and carnitine metabolism in isolated rat hepatocytes

    SciTech Connect

    Brass, E.P.; Beyerinck, R.A.

    1987-05-01

    Propionate (P) and its metabolic products P-CoA and methylmalonyl-CoA can disrupt normal hepatic metabolism. Carnitine (Cn) has been shown to partially restore cellular function in the presence of P. This effect of Cn may result from removal of propionyl groups as propionylcarnitine (P-Cn). The present study examined the kinetics of P-Cn formation in rat hepatocytes, and the consequence of P-Cn formation on P and Cn metabolism. /sup 14/C-P was converted to CO/sub 2/, glucose and P-Cn in the hepatocyte system. Increasing concentrations of Cn up to 10.0 mM increased P-Cn formation from P without affecting CO/sub 2/ or glucose formation. Thus, 10.0 mM Cn increased total P metabolism by 40%. Metabolism of P was associated with a decrease in Cn concentration and an increase in short chain acylcarnitines (SCCn). In the absence of added Cn, 60 min incubation with P decreased Cn from 6.8 to 2.5 ..mu..M with a corresponding increase in SCCn. This effect of P to deplete free Cn was not seen to the same degree with butyrate in place of P. Similar increases in the formation of SCCn in the presence of P at the expense of free Cn were seen when the incubation Cn concentration was increased to 50 ..mu..M or 150 ..mu..M. HPLC methodologies to study specific acylcarnitines demonstrated the accumulation of large amounts of P-Cn in the incubations containing P, accounting for the depletion of free Cn.

  10. Analysis of fluticasone propionate in induced sputum by mass spectrometry.

    PubMed

    Hagan, John B; Taylor, Robert L; Kita, Hirohito; Singh, Ravinder J

    2011-01-01

    Although evaluation of induced sputum has shown promise as a marker of eosinophilic airway inflammation in asthmatic subjects, most studies, to date, do not adequately address the potential effect that inhaled corticosteroids may have on sputum eosinophilia. This study was designed to prospectively evaluate analysis of fluticasone propionate (FP) in whole sputum by mass spectrometry as a tool to determine recent administration of inhaled FP. Induced sputum of nonsmoking asthmatic subjects was prospectively analyzed 16-24 hours after witnessed administration of orally inhaled FP. FP was extracted from whole sputum via an acetonitrile protein precipitation followed by methylene chloride liquid extraction of the supernatant (AB 4000; AB Sciex). A portion of the reconstituted sample was analyzed by liquid chromatography tandem mass spectrometry using a triple quad tandem mass spectrometer. Results were compared with those from nonsmoking asthmatic subjects not receiving inhaled FP. Twenty-two asthmatic subjects on FP and 9 asthmatic subjects without FP underwent sputum induction 16-24 hours following witnessed administration of FP. Sufficient sputum for analysis was obtained from 30 of 31 subjects. FP was detected in 22 of 22 asthmatic subjects receiving FP (range, 29-133,000 pg/mL) and was undetectable in 8 of 8 subjects not receiving FP. The sensitivity and specificity of tandem mass spectrometry's ability to detect FP in sputum was 100% and 100%, respectively. Analysis of FP in induced sputum is a reliable method to verify recent administration of inhaled FP. Induced asthmatic sputum from one induction may be used to concomitantly assess sputum eosinophilia as well as recent administration of FP.

  11. Stress induced reversible crystal transition in poly(butylene succinate)

    NASA Astrophysics Data System (ADS)

    Liu, Guoming; Zheng, Liuchun; Zhang, Xiuqin; Li, Chuncheng; Wang, Dujin

    2015-03-01

    The plastic deformation mechanism of semi-crystalline polymers is a long-studied topic, which is crucial for establishing structure/property relationships. For polymers with stress induced crystal transition, some open questions still need to be answered, such as on which stage of plastic deformation does the crystal transition take place, and more importantly, what happens on the lamellar structure during crystal transition. In this talk, stress-induced reversible crystal transition in poly(butylene succinate) was systematically investigated by in-situ WAXS and SAXS. A ``lamellar thickening'' phenomenon was observed during stretching, which was shown to mainly originated from the reversible crystal transition. This mechanism was shown to be valid in poly(ethylene succinate). The critical stress for the transition was measured in a series of PBS-based crystalline-amorphous multi-block copolymers. Interestingly, these PBS copolymers exhibited identical critical stress independent of amorphous blocks. The universal critical stress for crystal transition was interpreted through a single-microfibril-stretching mechanism. The work is financially supported by the National Natural Science Foundation of China (Grant No. 51203170).

  12. 40 CFR 721.10090 - Tertiary amine salt of glycol succinate (generic).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Tertiary amine salt of glycol... Specific Chemical Substances § 721.10090 Tertiary amine salt of glycol succinate (generic). (a) Chemical... as tertiary amine salt of glycol succinate (PMN P-01-595) is subject to reporting under this...

  13. 40 CFR 721.10090 - Tertiary amine salt of glycol succinate (generic).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Tertiary amine salt of glycol... Specific Chemical Substances § 721.10090 Tertiary amine salt of glycol succinate (generic). (a) Chemical... as tertiary amine salt of glycol succinate (PMN P-01-595) is subject to reporting under this...

  14. Study of the role of anaerobic metabolism in succinate production by Enterobacter aerogenes.

    PubMed

    Tajima, Yoshinori; Kaida, Kenichi; Hayakawa, Atsushi; Fukui, Keita; Nishio, Yousuke; Hashiguchi, Kenichi; Fudou, Ryosuke; Matsui, Kazuhiko; Usuda, Yoshihiro; Sode, Koji

    2014-09-01

    Succinate is a core biochemical building block; optimizing succinate production from biomass by microbial fermentation is a focus of basic and applied biotechnology research. Lowering pH in anaerobic succinate fermentation culture is a cost-effective and environmentally friendly approach to reducing the use of sub-raw materials such as alkali, which are needed for neutralization. To evaluate the potential of bacteria-based succinate fermentation under weak acidic (pH <6.2) and anaerobic conditions, we characterized the anaerobic metabolism of Enterobacter aerogenes AJ110637, which rapidly assimilates glucose at pH 5.0. Based on the profile of anaerobic products, we constructed single-gene knockout mutants to eliminate the main anaerobic metabolic pathways involved in NADH re-oxidation. These single-gene knockout studies showed that the ethanol synthesis pathway serves as the dominant NADH re-oxidation pathway in this organism. To generate a metabolically engineered strain for succinate production, we eliminated ethanol formation and introduced a heterogeneous carboxylation enzyme, yielding E. aerogenes strain ΔadhE/PCK. The strain produced succinate from glucose with a 60.5% yield (grams of succinate produced per gram of glucose consumed) at pH <6.2 and anaerobic conditions. Thus, we showed the potential of bacteria-based succinate fermentation under weak acidic conditions.

  15. [Environmental factors affecting the succinic acid production by Actinobacillus succinogenes CGMCC 1593].

    PubMed

    Zheng, Pu; Zhou, Wei; Ni, Ye; Jiang, Min; Wei, Ping; Sun, Zhihao

    2008-06-01

    Actinobacillus succinogenes is a promising candidate for the production of bio-based succinic acid. Previously, we isolated a succinic acid-producing strain Actinobacillus succinogenes CGMCC 1593 from bovine rumen. In this paper, the influence of the environmental factors such as gas phase, pH, ORP, on succinic acid production by A. succinogenes CGMCC 1593 was studied. The results showed that CO2 was the optimum gas phase for anaerobic fermentation ofA. succinogenes CGMCC 1593 as well as one of the substrate for the succinic acid synthesis. Using MgCO3 as a pH regulator, the pH was maintained within 7.1-6.2 during the anaerobic fermentation for the cell growth and acid production of A. succinogenes CGMCC 1593. Our results showed that low initial ORP was disadvantageous for the growth of A. succinogenes CGMCC 1593 and an ORP of -270 mV was demonstrated to be beneficial to the succinic acid production. By adding Na2S.9H2O to decrease ORP to -270 mV at the end of exponential growth phase in batch culture of A. succinogenes CGMCC 1593, the succinic acid concentration reached 37 g/L and the yield of succinic acid was 129% at 48 h. This work might provide valuable information for further optimization of succinic acid fermentation by A. succinogenes CGMCC 1593.

  16. Synthesis, characterization and nanocomposite formation of poly(glycerol succinate-co-maleate) with cellulose nanowhiskers

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A novel biodegradable polymer based on glycerol, succinic anhydride and maleic anhydride, poly(glycerol succinate-co-maleate), poly(GlySAMA), was synthesized by melt polycondensation and tested as a matrix for composites with cellulose nanowhiskers. This glycerol-based polymer is thermally stable as...

  17. 40 CFR 721.10090 - Tertiary amine salt of glycol succinate (generic).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Tertiary amine salt of glycol... Specific Chemical Substances § 721.10090 Tertiary amine salt of glycol succinate (generic). (a) Chemical... as tertiary amine salt of glycol succinate (PMN P-01-595) is subject to reporting under this...

  18. 40 CFR 721.10090 - Tertiary amine salt of glycol succinate (generic).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Tertiary amine salt of glycol... Specific Chemical Substances § 721.10090 Tertiary amine salt of glycol succinate (generic). (a) Chemical... as tertiary amine salt of glycol succinate (PMN P-01-595) is subject to reporting under this...

  19. 40 CFR 721.10090 - Tertiary amine salt of glycol succinate (generic).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Tertiary amine salt of glycol... Specific Chemical Substances § 721.10090 Tertiary amine salt of glycol succinate (generic). (a) Chemical... as tertiary amine salt of glycol succinate (PMN P-01-595) is subject to reporting under this...

  20. The effect of the bacterial product, succinic acid, on neutrophil bactericidal activity.

    PubMed

    Abdul-Majid, K B; Kenny, P A; Finlay-Jones, J J

    1997-02-01

    We investigated the effect of succinic acid on neutrophil bactericidal activity in a model of intra-abdominal abscess induced in mice by the peritoneal inoculation of 5 x 10(6) cfu ml-1 E. coli and 5 x 10(8) cfu ml-1 B. fragilis plus 1 mg of bran as faecal fibre analogue. The mean pH of the induced abscesses at week 1 was 6.7, higher than the pH associated with succinic acid inhibitory activity. We therefore determined the effect of succinic acid (0-100 mM) at pH 6.7 on the bactericidal activity of mouse bone marrow-derived neutrophils. Phagocytic killing of Proteus mirabilis by neutrophils was significantly inhibited by 30-100 mM succinic acid at pH 6.7 but there was no significant effect of succinic acid on engulfment of bacteria at this pH. However, significant inhibition of intracellular killing (assayed by adding succinic acid to suspensions of neutrophils which had engulfed bacteria in low serum concentrations but in the absence of succinic acid) was noted at 70 and 100 mM. These results indicate that succinic acid inhibits neutrophil bactericidal activity at a physiological pH, principally through inhibition of intracellular killing mechanisms and therefore contributing to bacterial persistence in this model of abscess formation.

  1. Integration of succinic acid and ethanol production within a corn or barley biorefinery

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Production of succinic acid from glucose by Escherichia coli strain AFP184 was studied in a batch fermentor. The bases used for pH control included NaOH, KOH, NH4OH, and Na2CO3. The yield of succinic acid without and with carbon dioxide supplied by an adjacent ethanol fermentor using either corn or ...

  2. Optimization of succinic acid fermentation with Actinobacillus succinogenes by response surface methodology (RSM).

    PubMed

    Zhang, Yun-jian; Li, Qiang; Zhang, Yu-xiu; Wang, Dan; Xing, Jian-min

    2012-02-01

    Succinic acid is considered as an important platform chemical. Succinic acid fermentation with Actinobacillus succinogenes strain BE-1 was optimized by central composite design (CCD) using a response surface methodology (RSM). The optimized production of succinic acid was predicted and the interactive effects between glucose, yeast extract, and magnesium carbonate were investigated. As a result, a model for predicting the concentration of succinic acid production was developed. The accuracy of the model was confirmed by the analysis of variance (ANOVA), and the validity was further proved by verification experiments showing that percentage errors between actual and predicted values varied from 3.02% to 6.38%. In addition, it was observed that the interactive effect between yeast extract and magnesium carbonate was statistically significant. In conclusion, RSM is an effective and useful method for optimizing the medium components and investigating the interactive effects, and can provide valuable information for succinic acid scale-up fermentation using A. succinogenes strain BE-1.

  3. Succination of proteins by fumarate: mechanism of inactivation of glyceraldehyde-3-phosphate dehydrogenase in diabetes.

    PubMed

    Blatnik, Matthew; Thorpe, Suzanne R; Baynes, John W

    2008-04-01

    S-(2-succinyl)cysteine (2SC) is a chemical modification of proteins formed by a Michael addition reaction between the Krebs cycle intermediate, fumarate, and thiol groups in protein--a process known as succination of protein. Succination causes irreversible inactivation of glyceraldehyde-3-phosphate dehydrogenase (GAPDH) in vitro. GAPDH was immunoprecipitated from muscle of diabetic rats, then analyzed by ultra-performance liquid chromatography-electrospray ionization-mass spectroscopy. Succination of GAPDH was increased in muscle of diabetic rats, and the extent of succination correlated strongly with the decrease in specific activity of the enzyme. We propose that 2SC is a biomarker of mitochondrial and oxidative stress in diabetes and that succination of GAPDH and other thiol proteins may provide the chemical link between glucotoxicity and the pathogenesis of diabetic complications.

  4. Aerobic production of succinate from arabinose by metabolically engineered Corynebacterium glutamicum.

    PubMed

    Chen, Tao; Zhu, Nianqing; Xia, Huihua

    2014-01-01

    Arabinose is considered as an ideal feedstock for the microbial production of value-added chemicals due to its abundance in hemicellulosic wastes. In this study, the araBAD operon from Escherichia coli was introduced into succinate-producing Corynebacterium glutamicum, which enabled aerobic production of succinate using arabinose as sole carbon source. The engineered strain ZX1 (pXaraBAD, pEacsAgltA) produced 74.4 mM succinate with a yield of 0.58 mol (mol arabinose)(-1), which represented 69.9% of the theoretically maximal yield. Moreover, this strain produced 110.2 mM succinate using combined substrates of glucose and arabinose. To date, this is the highest succinate production under aerobic conditions in minimal medium.

  5. Pharmacokinetic considerations of formulation: extended-release metoprolol succinate in the treatment of heart failure.

    PubMed

    Wikstrand, John; Andersson, Bert; Kendall, Martin J; Stanbrook, Hilary; Klibaner, Michael

    2003-02-01

    Extended-release (ER) metoprolol succinate is a controlled-release formulation designed to deliver metoprolol succinate at a near constant rate for approximately 20 h, independent of food intake and gastrointestinal pH. Once-daily dosing of ER metoprolol succinate 12.5-200 mg produces even plasma concentrations over a 24-h period, without the marked peaks and troughs characteristically observed with the immediate-release (IR) formulation. This leads to consistent beta1-blockade over 24 h, while maintaining cardioselectivity at doses up to 200 mg daily. Pharmacokinetic studies have also been performed in heart failure patients and have demonstrated that ER metoprolol succinate is associated with a more pronounced and even beta1-blockade over a 24-h period than the IR formulation. The efficacy and good tolerability of ER metoprolol succinate in heart failure patients has now been demonstrated in a large-scale clinical trial.

  6. Thermochemical pretreatments for enhancing succinic acid production from industrial hemp (Cannabis sativa L.).

    PubMed

    Gunnarsson, Ingólfur B; Kuglarz, Mariusz; Karakashev, Dimitar; Angelidaki, Irini

    2015-04-01

    The aim of this study was to develop an efficient thermochemical method for treatment of industrial hemp biomass, in order to increase its bioconversion to succinic acid. Industrial hemp was subjected to various thermochemical pretreatments using 0-3% H2SO4, NaOH or H2O2 at 121-180°C prior to enzymatic hydrolysis. The influence of the different pretreatments on hydrolysis and succinic acid production by Actinobacillus succinogenes 130Z was investigated in batch mode, using anaerobic bottles and bioreactors. Enzymatic hydrolysis and fermentation of hemp material pretreated with 3% H2O2 resulted in the highest overall sugar yield (73.5%), maximum succinic acid titer (21.9 g L(-1)), as well as the highest succinic acid yield (83%). Results obtained clearly demonstrated the impact of different pretreatments on the bioconversion efficiency of industrial hemp into succinic acid.

  7. GPR91 senses extracellular succinate released from inflammatory macrophages and exacerbates rheumatoid arthritis

    PubMed Central

    Zhang, Juan; Kneuer, Rainer

    2016-01-01

    When SUCNR1/GPR91-expressing macrophages are activated by inflammatory signals, they change their metabolism and accumulate succinate. In this study, we show that during this activation, macrophages release succinate into the extracellular milieu. They simultaneously up-regulate GPR91, which functions as an autocrine and paracrine sensor for extracellular succinate to enhance IL-1β production. GPR91-deficient mice lack this metabolic sensor and show reduced macrophage activation and production of IL-1β during antigen-induced arthritis. Succinate is abundant in synovial fluids from rheumatoid arthritis (RA) patients, and these fluids elicit IL-1β release from macrophages in a GPR91-dependent manner. Together, we reveal a GPR91/succinate-dependent feed-forward loop of macrophage activation and propose GPR91 antagonists as novel therapeutic principles to treat RA. PMID:27481132

  8. Propionic acid fermentation by Propionibacterium freudenreichii CCTCC M207015 in a multi-point fibrous-bed bioreactor.

    PubMed

    Feng, Xiao-Hai; Chen, Fei; Xu, Hong; Wu, Bo; Yao, Jun; Ying, Han-Jie; Ouyang, Ping-Kai

    2010-11-01

    Propionic acid was produced in a multi-point fibrous-bed (MFB) bioreactor by Propionibacterium freudenreichii CCTCC M207015. The MFB bioreactor, comprising spiral cotton fiber packed in a modified 7.5-l bioreactor, was effective for cell-immobilized propionic acid production compared with conventional free cell fermentation. Batch fermentations at various glucose concentrations were investigated in the MFB bioreactor. Based on analysis of the time course of production, a fed-batch strategy was applied for propionic acid production. The maximum propionic acid concentration was 67.05 g l(-1) after 496 h of fermentation, and the proportion of propionic acid to total organic acids was approximately 78.28% (w/w). The MFB bioreactor exhibited excellent production stability during batch fermentation and the propionic acid productivity remained high after 78 days of fermentation.

  9. EPR and optical studies of VO2+ doped potassium succinate-succinic acid single crystal - Substitutional incorporation

    NASA Astrophysics Data System (ADS)

    Juliet sheela, K.; Radha Krishnan, S.; Shanmugam, V. M.; Subramanian, P.

    2017-03-01

    EPR and optical absorption studies of VO2+ doped potassium succinate-succinic acid (KSSA) single crystal has been examined at room temperature. EPR spectrum shows that well resolved hyperfine lines. The angular variation of the EPR spectra has shown that two different VO2+ complexes are located in different chemical environments. Among the number of sites, two sites have been followed and reported here. From the EPR analysis, spin Hamiltonian parameters g and A tensors and their directional cosines are evaluated. Both the sites experience rhombic crystal field symmetry around the impurity ion. The VO2+ ion entering the site location of potassium ion has coordination of eight oxygen atoms in a distorted dodecahedral arrangement. The Optical absorption spectrum studied at room temperature shows bands corresponding to C4v symmetry. The crystal field parameter and tetragonal field parameters are calculated. From the Optical and EPR data various molecular orbital coefficients are evaluated and the nature of bonding in the crystal is discussed.

  10. Response of Syntrophic Propionate Degradation to pH Decrease and Microbial Community Shifts in an UASB Reactor.

    PubMed

    Zhang, Liguo; Ban, Qiaoying; Li, Jianzheng; Jha, Ajay Kumar

    2016-08-28

    The effect of pH on propionate degradation in an upflow anaerobic sludge blanket (UASB) reactor containing propionate as a sole carbon source was studied. Under influent propionate of 2,000 mg/l and 35ºC, propionate removal at pH 7.5-6.8 was above 93.6%. Propionate conversion was significantly inhibited with stepwise pH decrease from pH 6.8 to 6.5, 6.0, 5.5, 5.0, 4.5, and then to 4.0. After long-term operation, the propionate removal at pH 6.5-4.5 maintained an efficiency of 88.5%-70.1%, whereas propionate was hardly decomposed at pH 4.0. Microbial composition analysis showed that propionate-oxidizing bacteria from the genera Pelotomaculum and Smithella likely existed in this system. They were significantly reduced at pH ≤5.5. The methanogens in this UASB reactor belonged to four genera: Methanobacterium, Methanospirillum, Methanofollis, and Methanosaeta. Most detectable hydrogenotrophic methanogens were able to grow at low pH conditions (pH 6.0-4.0), but the acetotrophic methanogens were reduced as pH decreased. These results indicated that propionate-oxidizing bacteria and acetotrophic methanogens were more sensitive to low pH (5.5-4.0) than hydrogenotrophic methanogens.

  11. Tyrosine B10 triggers a heme propionate hydrogen bonding network loop with glutamine E7 moiety

    SciTech Connect

    Ramos-Santana, Brenda J.; Lopez-Garriga, Juan

    2012-08-10

    Highlights: Black-Right-Pointing-Pointer H-bonding network loop by PheB10Tyr mutation is proposed. Black-Right-Pointing-Pointer The propionate group H-bonding network restricted the flexibility of the heme. Black-Right-Pointing-Pointer The hydrogen bonding interaction modulates the electron density of the iron. Black-Right-Pointing-Pointer Propionate H-bonding network loop explains the heme-ligand stabilization. -- Abstract: Propionates, as peripheral groups of the heme active center in hemeproteins have been described to contribute in the modulation of heme reactivity and ligand selection. These electronic characteristics prompted the question of whether the presence of hydrogen bonding networks between propionates and distal amino acids present in the heme ligand moiety can modulate physiological relevant events, like ligand binding association and dissociation activities. Here, the role of these networks was evaluated by NMR spectroscopy using the hemoglobin I PheB10Tyr mutant from Lucina pectinata as model for TyrB10 and GlnE7 hemeproteins. {sup 1}H-NMR results for the rHbICN PheB10Tyr derivative showed chemical shifts of TyrB10 OH{eta} at 31.00 ppm, GlnE7 N{sub {epsilon}1}H/N{sub {epsilon}2}H at 10.66 ppm/-3.27 ppm, and PheE11 C{sub {delta}}H at 11.75 ppm, indicating the presence of a crowded, collapsed, and constrained distal pocket. Strong dipolar contacts and inter-residues crosspeaks between GlnE7/6-propionate group, GlnE7/TyrB10 and TyrB10/CN suggest that this hydrogen bonding network loop between GlnE7, TyrB10, 6-propionate group, and the heme ligand contribute significantly to the modulation of the heme iron electron density as well as the ligand stabilization mechanism. Therefore, the network loop presented here support the fact that the electron withdrawing character of the hydrogen bonding is controlled by the interaction of the propionates and the nearby electronic environments contributing to the modulation of the heme electron density state. Thus

  12. 21 CFR 184.1185 - Calcium acetate.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    .... No. 62-54-4), also known as acetate of lime or vinegar salts, is the calcium salt of acetic acid. It may be produced by the calcium hydroxide neutralization of acetic acid. (b) The ingredient meets...

  13. 21 CFR 184.1185 - Calcium acetate.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    .... No. 62-54-4), also known as acetate of lime or vinegar salts, is the calcium salt of acetic acid. It may be produced by the calcium hydroxide neutralization of acetic acid. (b) The ingredient meets...

  14. 21 CFR 184.1185 - Calcium acetate.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    .... No. 62-54-4), also known as acetate of lime or vinegar salts, is the calcium salt of acetic acid. It may be produced by the calcium hydroxide neutralization of acetic acid. (b) The ingredient meets...

  15. 21 CFR 184.1185 - Calcium acetate.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... as acetate of lime or vinegar salts, is the calcium salt of acetic acid. It may be produced by the calcium hydroxide neutralization of acetic acid. (b) The ingredient meets the specifications of the...

  16. Metabolic network rewiring of propionate flux compensates vitamin B12 deficiency in C. elegans

    PubMed Central

    Watson, Emma; Olin-Sandoval, Viridiana; Hoy, Michael J; Li, Chi-Hua; Louisse, Timo; Yao, Victoria; Mori, Akihiro; Holdorf, Amy D; Troyanskaya, Olga G; Ralser, Markus; Walhout, Albertha JM

    2016-01-01

    Metabolic network rewiring is the rerouting of metabolism through the use of alternate enzymes to adjust pathway flux and accomplish specific anabolic or catabolic objectives. Here, we report the first characterization of two parallel pathways for the breakdown of the short chain fatty acid propionate in Caenorhabditis elegans. Using genetic interaction mapping, gene co-expression analysis, pathway intermediate quantification and carbon tracing, we uncover a vitamin B12-independent propionate breakdown shunt that is transcriptionally activated on vitamin B12 deficient diets, or under genetic conditions mimicking the human diseases propionic- and methylmalonic acidemia, in which the canonical B12-dependent propionate breakdown pathway is blocked. Our study presents the first example of transcriptional vitamin-directed metabolic network rewiring to promote survival under vitamin deficiency. The ability to reroute propionate breakdown according to B12 availability may provide C. elegans with metabolic plasticity and thus a selective advantage on different diets in the wild. DOI: http://dx.doi.org/10.7554/eLife.17670.001 PMID:27383050

  17. Evaluating the potential impact of proton carriers on syntrophic propionate oxidation

    NASA Astrophysics Data System (ADS)

    Juste-Poinapen, Natacha M. S.; Turner, Mark S.; Rabaey, Korneel; Virdis, Bernardino; Batstone, Damien J.

    2015-12-01

    Anaerobic propionic acid degradation relies on interspecies electron transfer (IET) between propionate oxidisers and electron acceptor microorganisms, via either molecular hydrogen, formate or direct transfers. We evaluated the possibility of stimulating direct IET, hence enhancing propionate oxidation, by increasing availability of proton carriers to decrease solution resistance and reduce pH gradients. Phosphate was used as a proton carrying anion, and chloride as control ion together with potassium as counter ion. Propionic acid consumption in anaerobic granules was assessed in a square factorial design with ratios (1:0, 2:1, 1:1, 1:2 and 0:1) of total phosphate (TP) to Cl-, at 1X, 10X, and 30X native conductivity (1.5 mS.cm-1). Maximum specific uptake rate, half saturation, and time delay were estimated using model-based analysis. Community profiles were analysed by fluorescent in situ hybridisation and 16S rRNA gene pyrosequencing. The strongest performance was at balanced (1:1) ratios at 10X conductivity where presumptive propionate oxidisers namely Syntrophobacter and Candidatus Cloacamonas were more abundant. There was a shift from Methanobacteriales at high phosphate, to Methanosaeta at low TP:Cl ratios and low conductivity. A lack of response to TP, and low percentage of presumptive electroactive organisms suggested that DIET was not favoured under the current experimental conditions.

  18. Evaluating the potential impact of proton carriers on syntrophic propionate oxidation

    PubMed Central

    Juste-Poinapen, Natacha M. S.; Turner, Mark S.; Rabaey, Korneel; Virdis, Bernardino; Batstone, Damien J.

    2015-01-01

    Anaerobic propionic acid degradation relies on interspecies electron transfer (IET) between propionate oxidisers and electron acceptor microorganisms, via either molecular hydrogen, formate or direct transfers. We evaluated the possibility of stimulating direct IET, hence enhancing propionate oxidation, by increasing availability of proton carriers to decrease solution resistance and reduce pH gradients. Phosphate was used as a proton carrying anion, and chloride as control ion together with potassium as counter ion. Propionic acid consumption in anaerobic granules was assessed in a square factorial design with ratios (1:0, 2:1, 1:1, 1:2 and 0:1) of total phosphate (TP) to Cl−, at 1X, 10X, and 30X native conductivity (1.5 mS.cm−1). Maximum specific uptake rate, half saturation, and time delay were estimated using model-based analysis. Community profiles were analysed by fluorescent in situ hybridisation and 16S rRNA gene pyrosequencing. The strongest performance was at balanced (1:1) ratios at 10X conductivity where presumptive propionate oxidisers namely Syntrophobacter and Candidatus Cloacamonas were more abundant. There was a shift from Methanobacteriales at high phosphate, to Methanosaeta at low TP:Cl ratios and low conductivity. A lack of response to TP, and low percentage of presumptive electroactive organisms suggested that DIET was not favoured under the current experimental conditions. PMID:26670292

  19. Enzyme IIANtr Regulates Salmonella Invasion Via 1,2-Propanediol And Propionate Catabolism

    PubMed Central

    Yoo, Woongjae; Kim, Dajeong; Yoon, Hyunjin; Ryu, Sangryeol

    2017-01-01

    Many Proteobacteria possess a nitrogen-metabolic phosphotransferase system (PTSNtr) consisting of EINtr, NPr, and EIIANtr (encoded by ptsP, ptsO, and ptsN, respectively). The PTSNtr plays diverse regulatory roles, but the substrate phosphorylated by EIIANtr and its primary functions have not yet been identified. To comprehensively understand the roles of PTSNtr in Salmonella Typhimurium, we compared the whole transcriptomes of wild-type and a ΔptsN mutant. Genome-wide RNA sequencing revealed that 3.5% of the annotated genes were up- or down-regulated by three-fold or more in the absence of EIIANtr. The ΔptsN mutant significantly down-regulated the expression of genes involved in vitamin B12 synthesis, 1,2-propanediol utilization, and propionate catabolism. Moreover, the invasiveness of the ΔptsN mutant increased about 5-fold when 1,2-propanediol or propionate was added, which was attributable to the increased stability of HilD, the transcriptional regulator of Salmonella pathogenicity island-1. Interestingly, an abundance of 1,2-propanediol or propionate promoted the production of EIIANtr, suggesting the possibility of a positive feedback loop between EIIANtr and two catabolic pathways. These results demonstrate that EIIANtr is a key factor for the utilization of 1,2-propanediol and propionate as carbon and energy sources, and thereby modulates the invasiveness of Salmonella via 1,2-propanediol or propionate catabolism. PMID:28333132

  20. Pallidol hexa­acetate ethyl acetate monosolvate

    PubMed Central

    Mao, Qinyong; Taylor, Dennis K.; Ng, Seik Weng; Tiekink, Edward R. T.

    2013-01-01

    The entire mol­ecule of pallidol hexa­acetate {systematic name: (±)-(4bR,5R,9bR,10R)-5,10-bis­[4-(acet­yloxy)phen­yl]-4b,5,9b,10-tetra­hydro­indeno­[2,1-a]indene-1,3,6,8-tetrayl tetra­acetate} is completed by the application of twofold rotational symmetry in the title ethyl acetate solvate, C40H34O12·C4H8O2. The ethyl acetate mol­ecule was highly disordered and was treated with the SQUEEZE routine [Spek (2009 ▶). Acta Cryst. D65, 148–155]; the crystallographic data take into account the presence of the solvent. In pallidol hexa­acetate, the dihedral angle between the fused five-membered rings (r.m.s. deviation = 0.100 Å) is 54.73 (6)°, indicating a significant fold in the mol­ecule. Significant twists between residues are also evident as seen in the dihedral angle of 80.70 (5)° between the five-membered ring and the pendent benzene ring to which it is attached. Similarly, the acetate residues are twisted with respect to the benzene ring to which they are attached [C—O(carb­oxy)—C—C torsion angles = −70.24 (14), −114.43 (10) and −72.54 (13)°]. In the crystal, a three-dimensional architecture is sustained by C—H⋯O inter­actions which encompass channels in which the disordered ethyl acetate mol­ecules reside. PMID:24046702

  1. Desvenlafaxine succinate for the treatment of major depressive disorder.

    PubMed

    Lohoff, Falk W; Rickels, Karl

    2008-08-01

    Major depressive disorder (MDD) remains one of the most common psychiatric disorders with high morbidity and mortality. Effective treatment is limited and response/remission to antidepressant pharmacotherapy remains poor and unpredictable. The development of new antidepressants is thus of great importance to the field. Desvenlafaxine succinate (DVS) is the active metabolite of the serotonin and noradrenaline re-uptake inhibitor venlafaxine and was recently FDA approved for the treatment of MDD. DVS showed efficacy in clinical trials in MDD with doses ranging from 50 - 400 mg. Advantages compared to other antidepressants include once daily dosing at effective doses, no CYP450 metabolism and low drug-drug interactions. Concerns include side effect profile and moderate efficacy. DVS might be a useful addition to the arsenal of antidepressants available to the clinician. Additional studies, in particular head-to-head comparison to other antidepressants and long-term treatment studies, will be necessary to comprehensively evaluate DVS safety and efficacy for clinical practice.

  2. Succinic acid production from lignocellulosic hydrolysate by Basfia succiniciproducens.

    PubMed

    Salvachúa, Davinia; Smith, Holly; St John, Peter C; Mohagheghi, Ali; Peterson, Darren J; Black, Brenna A; Dowe, Nancy; Beckham, Gregg T

    2016-08-01

    The production of chemicals alongside fuels will be essential to enhance the feasibility of lignocellulosic biorefineries. Succinic acid (SA), a naturally occurring C4-diacid, is a primary intermediate of the tricarboxylic acid cycle and a promising building block chemical that has received significant industrial attention. Basfia succiniciproducens is a relatively unexplored SA-producing bacterium with advantageous features such as broad substrate utilization, genetic tractability, and facultative anaerobic metabolism. Here B. succiniciproducens is evaluated in high xylose-content hydrolysates from corn stover and different synthetic media in batch fermentation. SA titers in hydrolysate at an initial sugar concentration of 60g/L reached up to 30g/L, with metabolic yields of 0.69g/g, and an overall productivity of 0.43g/L/h. These results demonstrate that B. succiniciproducens may be an attractive platform organism for bio-SA production from biomass hydrolysates.

  3. Succinic acid production from lignocellulosic hydrolysate by Basfia succiniciproducens

    SciTech Connect

    Salvachúa, Davinia; Smith, Holly; St. John, Peter C.; Mohagheghi, Ali; Peterson, Darren J.; Black, Brenna A.; Dowe, Nancy; Beckham, Gregg T.

    2016-05-09

    The production of chemicals alongside fuels will be essential to enhance the feasibility of lignocellulosic biorefineries. Succinic acid (SA), a naturally occurring C4-diacid, is a primary intermediate of the tricarboxylic acid cycle and a promising building block chemical that has received significant industrial attention. Basfia succiniciproducens is a relatively unexplored SA-producing bacterium with advantageous features such as broad substrate utilization, genetic tractability, and facultative anaerobic metabolism. Here B. succiniciproducens is evaluated in high xylose-content hydrolysates from corn stover and different synthetic media in batch fermentation. SA titers in hydrolysate at an initial sugar concentration of 60 g/L reached up to 30 g/L, with metabolic yields of 0.69 g/g, and an overall productivity of 0.43 g/L/h. These results demonstrate that B. succiniciproducens may be an attractive platform organism for bio-SA production from biomass hydrolysates.

  4. Succinic acid production from lignocellulosic hydrolysate by Basfia succiniciproducens

    DOE PAGES

    Salvachúa, Davinia; Smith, Holly; St. John, Peter C.; ...

    2016-05-09

    The production of chemicals alongside fuels will be essential to enhance the feasibility of lignocellulosic biorefineries. Succinic acid (SA), a naturally occurring C4-diacid, is a primary intermediate of the tricarboxylic acid cycle and a promising building block chemical that has received significant industrial attention. Basfia succiniciproducens is a relatively unexplored SA-producing bacterium with advantageous features such as broad substrate utilization, genetic tractability, and facultative anaerobic metabolism. Here B. succiniciproducens is evaluated in high xylose-content hydrolysates from corn stover and different synthetic media in batch fermentation. SA titers in hydrolysate at an initial sugar concentration of 60 g/L reached up tomore » 30 g/L, with metabolic yields of 0.69 g/g, and an overall productivity of 0.43 g/L/h. These results demonstrate that B. succiniciproducens may be an attractive platform organism for bio-SA production from biomass hydrolysates.« less

  5. Towards large scale fermentative production of succinic acid.

    PubMed

    Jansen, Mickel L A; van Gulik, Walter M

    2014-12-01

    Fermentative production of succinic acid (SA) from renewable carbohydrate feed-stocks can have the economic and sustainability potential to replace petroleum-based production in the future, not only for existing markets, but also new larger volume markets. To accomplish this, extensive efforts have been undertaken in the field of strain construction and metabolic engineering to optimize SA production in the last decade. However, relatively little effort has been put into fermentation process development. The choice for a specific host organism determines to a large extent the process configuration, which in turn influences the environmental impact of the overall process. In the last five years, considerable progress has been achieved towards commercialization of fermentative production of SA. Several companies have demonstrated their confidence about the economic feasibility of fermentative SA production by transferring their processes from pilot to production scale.

  6. Redox dependent changes at the heme propionates in cytochrome c oxidase from Paracoccus denitrificans: direct evidence from FTIR difference spectroscopy in combination with heme propionate 13C labeling.

    PubMed

    Behr, J; Hellwig, P; Mäntele, W; Michel, H

    1998-05-19

    Specific isotope labeling at the carboxyl groups of the four heme propionates of cytochrome c oxidase from Paracoccus denitrificans was used in order to assign signals observed in electrochemically induced redox Fourier transform infrared (FTIR) difference spectra of this enzyme. For this purpose, the hemA gene of the P. denitrificans strain PD1222, coding for 5-aminolevulinate synthase, was deleted by partial replacement with a kanamycin resistance cartridge, resulting in a stable 5-aminolevulinic acid (ALA) auxotrophy. Normal growth of this deficient strain and cytochrome c oxidase yield comparable to that of P. dentrificans wild-type strain PD1222 could be obtained by supplementation with 0.1 mM ALA in the growth medium. Visible spectra and reduced-minus-oxidized FTIR spectra showed that the purified cytochrome c oxidase had spectral characteristics identical to those of the wild-type enzyme. The decrease of a negative signal at 1676 cm-1 in the reduced-minus-oxidized FTIR difference spectra of the 13C-labeled cytochrome c oxidase in comparison to those of the unlabeled protein allowed the assignment of this signal to a COOH vibration mode of at least one of the four heme propionates. Moreover, a negative band at approximately 1570 cm-1 shifted to smaller wavenumbers in the spectra of the 13C-labeled enzyme in comparison to the spectra of the unlabeled enzyme and was thus assigned to contributions from an antisymmetric COO- mode of one or more of the four heme propionates. Additionally, a positive signal at 1538 cm-1 shifted to approximately 1500 cm-1 in the spectra of the isotopically labeled protein and was therefore assigned to at least one antisymmetric COO- mode of the heme propionates. A negative signal at 1390 cm-1, which has been shifted to 1360 cm-1 in the spectra of the 13C-labeled enzyme, is due to a symmetric COO- mode from at least one heme propionate. These results suggest that at least two of the four heme propionates in cytochrome c oxidase

  7. Purification and characterization of Plasmodium falciparum succinate dehydrogenase.

    PubMed

    Suraveratum, N; Krungkrai, S R; Leangaramgul, P; Prapunwattana, P; Krungkrai, J

    2000-02-05

    Succinate dehydrogenase (SDH), a Krebs cycle enzyme and complex II of the mitochondrial electron transport system was purified to near homogeneity from the human malarial parasite Plasmodium falciparum cultivated in vitro by FPLC on Mono Q, Mono S and Superose 6 gel filtration columns. The malarial SDH activity was found to be extremely labile. Based on Superose 6 FPLC, sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and nondenaturing-PAGE analyses, it was demonstrated that the malarial enzyme had an apparent native molecular mass of 90 +/- 8 kDa and contained two major subunits with molecular masses of 55 +/- 6 and 35 +/- 4 kDa (n = 8). The enzymatic reaction required both succinate and coenzyme Q (CoQ) for its maximal catalysis with Km values of 3 and 0.2 microM, and k(cat) values of 0.11 and 0.06 min(-1), respectively. Catalytic efficiency of the malarial SDH for both substrates were found to be relatively low (approximately 600-5000 M(-1) s(-1)). Fumarate, malonate and oxaloacetate were found to inhibit the malarial enzyme with Ki values of 81, 13 and 12 microM, respectively. The malarial enzyme activity was also inhibited by substrate analog of CoQ, 5-hydroxy-2-methyl-1,4-naphthoquinone, with a 50% inhibitory concentration of 5 microM. The quinone had antimalarial activity against the in vitro growth of P. falciparum with a 50% inhibitory concentration of 0.27 microM and was found to completely inhibit oxygen uptake of the parasite at a concentration of 0.88 microM. A known inhibitor of mammalian mitochondrial SDH, 2-thenoyltrifluoroacetone. had no inhibitory effect on both the malarial SDH activity and the oxygen uptake of the parasite at a concentration of 50 microM. Many properties observed in the malarial SDH were found to be different from the host mammalian enzyme.

  8. Mitochondrial stress causes increased succination of proteins in adipocytes in response to glucotoxicity.

    PubMed

    Frizzell, Norma; Thomas, Sonia A; Carson, James A; Baynes, John W

    2012-07-15

    2SC [S-(2-succino)-cysteine] is a chemical modification formed by a Michael addition reaction of fumarate with cysteine residues in proteins. Formation of 2SC, termed 'succination' of proteins, increases in adipocytes grown in high-glucose medium and in adipose tissues of Type 2 diabetic mice. However, the metabolic mechanisms leading to increased fumarate and succination of protein in the adipocyte are unknown. Treatment of 3T3 cells with high glucose (30 mM compared with 5 mM) caused a significant increase in cellular ATP/ADP, NADH/NAD+ and Δψm (mitochondrial membrane potential). There was also a significant increase in the cellular fumarate concentration and succination of proteins, which may be attributed to the increase in NADH/NAD+ and subsequent inhibition of tricarboxylic acid cycle NAD+-dependent dehydrogenases. Chemical uncouplers, which dissipated Δψm and reduced the NADH/NAD+ ratio, also decreased the fumarate concentration and protein succination. High glucose plus metformin, an inhibitor of complex I in the electron transport chain, caused an increase in fumarate and succination of protein. Thus excess fuel supply (glucotoxicity) appears to create a pseudohypoxic environment (high NADH/NAD+ without hypoxia), which drives the increase in succination of protein. We propose that increased succination of proteins is an early marker of glucotoxicity and mitochondrial stress in adipose tissue in diabetes.

  9. Production of Succinic Acid from Citric Acid and Related Acids by Lactobacillus Strains

    PubMed Central

    Kaneuchi, Choji; Seki, Masako; Komagata, Kazuo

    1988-01-01

    A number of Lactobacillus strains produced succinic acid in de Man-Rogosa-Sharpe broth to various extents. Among 86 fresh isolates from fermented cane molasses in Thailand, 30 strains (35%) produced succinic acid; namely, 23 of 39 Lactobacillus reuteri strains, 6 of 18 L. cellobiosus strains, and 1 of 6 unidentified strains. All of 10 L. casei subsp. casei strains, 5 L. casei subsp. rhamnosus strains, 6 L. mali strains, and 2 L. buchneri strains did not produce succinic acid. Among 58 known strains including 48 type strains of different Lactobacillus species, the strains of L. acidophilus, L. crispatus, L. jensenii, and L. parvus produced succinic acid to the same extent as the most active fresh isolates, and those of L. alimentarius, L. collinoides, L. farciminis, L. fructivorans (1 of 2 strains tested), L. malefermentans, and L. reuteri were also positive, to lesser extents. Diammonium citrate in de Man-Rogosa-Sharpe broth was determined as a precursor of the succinic acid produced. Production rates were about 70% on a molar basis with two fresh strains tested. Succinic acid was also produced from fumaric and malic acids but not from dl-isocitric, α-ketoglutaric, and pyruvic acids. The present study is considered to provide the first evidence on the production of succinic acid, an important flavoring substance in dairy products and fermented beverages, from citrate by lactobacilli. PMID:16347795

  10. Activating Phosphoenolpyruvate Carboxylase and Phosphoenolpyruvate Carboxykinase in Combination for Improvement of Succinate Production

    PubMed Central

    Tan, Zaigao; Zhu, Xinna; Chen, Jing; Li, Qingyan

    2013-01-01

    Phosphoenolpyruvate (PEP) carboxylation is an important step in the production of succinate by Escherichia coli. Two enzymes, PEP carboxylase (PPC) and PEP carboxykinase (PCK), are responsible for PEP carboxylation. PPC has high substrate affinity and catalytic velocity but wastes the high energy of PEP. PCK has low substrate affinity and catalytic velocity but can conserve the high energy of PEP for ATP formation. In this work, the expression of both the ppc and pck genes was modulated, with multiple regulatory parts of different strengths, in order to investigate the relationship between PPC or PCK activity and succinate production. There was a positive correlation between PCK activity and succinate production. In contrast, there was a positive correlation between PPC activity and succinate production only when PPC activity was within a certain range; excessive PPC activity decreased the rates of both cell growth and succinate formation. These two enzymes were also activated in combination in order to recruit the advantages of each for the improvement of succinate production. It was demonstrated that PPC and PCK had a synergistic effect in improving succinate production. PMID:23747698

  11. Succinic acid production from Bacteroides fragilis: process optimization and scale up in a bioreactor.

    PubMed

    Isar, Jasmine; Agarwal, Lata; Saran, Saurabh; Saxena, Rajendra Kumar

    2006-01-01

    We report the effect of different physiological and nutritional parameters on succinic acid production from Bacteroides fragilis. This strain initially produced 0.70gL(-1) of succinic acid in 60h. However, when process optimization was employed, 5.4gL(-1) of succinic acid was produced in medium consisting of glucose (1.5%); tryptone (2.5%); Na(2)CO(3) (1.5%), at pH 7.0, when inoculated with 4% inoculum and incubated at 37 degrees C, 100rpm for 48h. A marked enhancement in succinic acid production was observed when the optimized conditions were employed in a 10L bioreactor. A total of 12.5gL(-1) of succinic acid was produced in 30h. This is approximately 12-fold increase in succinic acid production when compared to the initial un-optimized medium production. This enhancement in succinic acid production may be due to the control of CO(2) supply and the impeller speed. This is also resulted in the reduction of the production time. The present study provides useful information to the industrialists seeking environmentally benign technology for the production of bulk biomolecules through manipulation of various chemical parameters.

  12. The succinate receptor as a novel therapeutic target for oxidative and metabolic stress-related conditions.

    PubMed

    Ariza, Ana Carolina; Deen, Peter Meinardus T; Robben, Joris Hubertus

    2012-01-01

    The succinate receptor (also known as GPR91) is a G protein-coupled receptor that is closely related to the family of P2Y purinoreceptors. It is expressed in a variety of tissues, including blood cells, adipose tissue, the liver, retina, and kidney. In these tissues, this receptor and its ligand succinate have recently emerged as novel mediators in local stress situations, including ischemia, hypoxia, toxicity, and hyperglycemia. Amongst others, the succinate receptor is involved in recruitment of immune cells to transplanted tissues. Moreover, it was shown to play a key role in the development of diabetic retinopathy. However, most prominently, the role of locally increased succinate levels and succinate receptor activation in the kidney, stimulating the systemic and local renin-angiotensin system, starts to unfold: the succinate receptor is a key mediator in the development of hypertension and possibly fibrosis in diabetes mellitus and metabolic syndrome. This makes the succinate receptor a promising drug target to counteract or prevent cardiovascular and fibrotic defects in these expanding disorders. Recent development of SUCNR1-specific antagonists opens novel possibilities for research in models for these disorders and may eventually provide novel opportunities for the treatment of patients.

  13. The Succinate Receptor as a Novel Therapeutic Target for Oxidative and Metabolic Stress-Related Conditions

    PubMed Central

    Ariza, Ana Carolina; Deen, Peter Meinardus T.; Robben, Joris Hubertus

    2012-01-01

    The succinate receptor (also known as GPR91) is a G protein-coupled receptor that is closely related to the family of P2Y purinoreceptors. It is expressed in a variety of tissues, including blood cells, adipose tissue, the liver, retina, and kidney. In these tissues, this receptor and its ligand succinate have recently emerged as novel mediators in local stress situations, including ischemia, hypoxia, toxicity, and hyperglycemia. Amongst others, the succinate receptor is involved in recruitment of immune cells to transplanted tissues. Moreover, it was shown to play a key role in the development of diabetic retinopathy. However, most prominently, the role of locally increased succinate levels and succinate receptor activation in the kidney, stimulating the systemic and local renin–angiotensin system, starts to unfold: the succinate receptor is a key mediator in the development of hypertension and possibly fibrosis in diabetes mellitus and metabolic syndrome. This makes the succinate receptor a promising drug target to counteract or prevent cardiovascular and fibrotic defects in these expanding disorders. Recent development of SUCNR1-specific antagonists opens novel possibilities for research in models for these disorders and may eventually provide novel opportunities for the treatment of patients. PMID:22649411

  14. ATP-Based Ratio Regulation of Glucose and Xylose Improved Succinate Production

    PubMed Central

    Zhang, Fengyu; Li, Jiaojiao; Liu, Huaiwei; Liang, Quanfeng; Qi, Qingsheng

    2016-01-01

    We previously engineered E. coli YL104H to efficiently produce succinate from glucose. Furthermore, the present study proved that YL104H could also co-utilize xylose and glucose for succinate production. However, anaerobic succinate accumulation using xylose as the sole carbon source failed, probably because of an insufficient supply of energy. By analyzing the ATP generation under anaerobic conditions in the presence of glucose or xylose, we indicated that succinate production was affected by the intracellular ATP level, which can be simply regulated by the substrate ratio of xylose to glucose. This finding was confirmed by succinate production using an artificial mixture containing different xylose to glucose ratios. Using xylose mother liquor, a waste containing both glucose and xylose derived from xylitol production, a final succinate titer of 61.66 g/L with an overall productivity of 0.95 g/L/h was achieved, indicating that the regulation of the intracellular ATP level may be a useful and efficient strategy for succinate production and can be extended to other anaerobic processes. PMID:27315279

  15. Enhanced succinic acid production from corncob hydrolysate by microbial electrolysis cells.

    PubMed

    Zhao, Yan; Cao, Weijia; Wang, Zhen; Zhang, Bowen; Chen, Kequan; Ouyang, Pingkai

    2016-02-01

    In this study, Actinobacillus succinogenes NJ113 microbial electrolysis cells (MECs) were used to enhance the reducing power responsible for succinic acid production from corncob hydrolysate. During corncob hydrolysate fermentation, electric MECs resulted in a 1.31-fold increase in succinic acid production and a 1.33-fold increase in the reducing power compared with those in non-electric MECs. When the hydrolysate was detoxified by combining Ca(OH)2, NaOH, and activated carbon, succinic acid production increased from 3.47 to 6.95 g/l. Using a constant potential of -1.8 V further increased succinic acid production to 7.18 g/l. A total of 18.09 g/l of succinic acid and a yield of 0.60 g/g total sugar were obtained after a 60-h fermentation when NaOH was used as a pH regulator. The improved succinic acid yield from corncob hydrolysate fermentation using A. succinogenes NJ113 in electric MECs demonstrates the great potential of using biomass as a feedstock to cost-effectively produce succinate.

  16. Mechanistic Insights into the Catalytic Oxidation of Carboxylic Acids on Au/TiO2: Partial Oxidation of Propionic and Butyric Acid to Gold Ketenylidene through Unsaturated Acids

    SciTech Connect

    McEntee, Monica; Tang, Wenjie; Neurock, Matthew; Yates, Jr., John T.

    2014-12-12

    Here, the partial oxidation of model C2–C4 (acetic, propionic, and butyric) carboxylic acids on Au/TiO2 catalysts consisting of Au particles ~3 nm in size was investigated using transmission infrared spectroscopy and density functional theory. All three acids readily undergo oxidative dehydrogenation on Au/TiO2. Propionic and butyric acid dehydrogenate at the C2–C3 positions, whereas acetic acid dehydrogenates at the C1–C2 position. The resulting acrylate and crotonate intermediates are subsequently oxidized to form β-keto acids that decarboxylate. All three acids form a gold ketenylidene intermediate, Au2C=C=O, along the way to their full oxidation to form CO2. Infrared measurements of Au2C=C=O formation as a function of time provides a surface spectroscopic probe of the kinetics for the activation and oxidative dehydrogenation of the alkyl groups in the carboxylate intermediates that form.

  17. Impact of trace element addition on degradation efficiency of volatile fatty acids, oleic acid and phenyl acetate and on microbial populations in a biogas digester.

    PubMed

    Karlsson, Anna; Einarsson, Peter; Schnürer, Anna; Sundberg, Carina; Ejlertsson, Jörgen; Svensson, Bo H

    2012-10-01

    The effect of trace element addition on anaerobic digestion of food industry- and household waste was studied using two semi-continuous lab-scale reactors, one (R30+) was supplied with Fe, Co and Ni, while the other (R30) acted as a control. Tracer analysis illustrated that methane production from acetate proceeded through syntrophic acetate oxidation (SAO) in both digesters. The effect of the trace elements was also evaluated in batch assays to determine the capacity of the microorganisms of the two digesters to degrade acetate, phenyl acetate, oleic acid or propionate, butyrate and valerate provided as a cocktail. The trace elements addition improved the performance of the process giving higher methane yields during start-up and early operation and lower levels of mainly acetate and propionate in the R30+ reactor. The batch assay showed that material from R30+ gave effects on methane production from all substrates tested. Phenyl acetate was observed to inhibit methane formation in the R30 but not in the R30+ assay. A real-time PCR analysis targeting methanogens on the order level as well as three SAO bacteria showed an increase in Methanosarcinales in the R30+ reactor over time, even though SAO continuously was the dominating pathway for methane production. Possibly, this increase explains the low VFA-levels and higher degradation rates observed in the R30+ batch incubations. These results show that the added trace elements affected the ability of the microflora to degrade VFAs as well as oleic acid and phenyl acetate in a community, where acetate utilization is dominated by SAO.

  18. L-carnitine enhances excretion of propionyl coenzyme A as propionylcarnitine in propionic acidemia.

    PubMed Central

    Roe, C R; Millington, D S; Maltby, D A; Bohan, T P; Hoppel, C L

    1984-01-01

    Treatment with L-carnitine greatly enhanced the formation and excretion of short-chain acylcarnitines in three patients with propionic acidemia and in three normal controls. The use of fast atom bombardment mass spectrometry and linked scanning at constant magnetic (B) to electric (E) field ratio identified the acylcarnitine as propionylcarnitine in patients with propionic acidemia. The normal children excreted mostly acetylcarnitine. Propionic acidemia and other organic acidurias are characterized by the intramitochondrial accumulation of short-chain acyl-Coenzyme A (CoA) compounds. The substrate specificity of the carnitine acetyltransferase enzyme and its steady state nature appears to facilitate elimination of propionyl groups while restoring the acyl-CoA:free CoA ratio in the mitochondrion. We suggest that L-carnitine may be a useful therapeutic approach for elimination of toxic acyl CoA compounds in several of these disorders. PMID:6725560

  19. The performance efficiency of bioaugmentation to prevent anaerobic digestion failure from ammonia and propionate inhibition.

    PubMed

    Li, Ying; Zhang, Yue; Sun, Yongming; Wu, Shubiao; Kong, Xiaoying; Yuan, Zhenhong; Dong, Renjie

    2017-05-01

    This study aims to investigate the effect of bioaugmentation with enriched methanogenic propionate degrading microbial consortia on propionate fermentation under ammonia stress from total ammonia nitrogen concentration (TAN) of 3.0gNL(-1). Results demonstrated that bioaugmentation could prevent unstable digestion against further deterioration. After 45days of 1dosage (0.3g dry cell weight L(-1)d(-1), DCW L(-1)d(-1)) of bioaugmentation, the average volumetric methane production (VMP), methane recovery rate and propionic acid (HPr) degradation rate was enhanced by 70mLL(-1)d(-1), 21% and 51%, respectively. In contrast, the non-bioaugmentation reactor almost failed. Routine addition of a double dosage (0.6g DCW L(-1)d(-1)) of bioaugmentation culture was able to effectively recover the failing digester. The results of FISH suggested that the populations of Methanosaetaceae increased significantly, which could be a main contributor for the positive effect on methane production.

  20. Modification of Sexual Development and Carotene Production by Acetate and Other Small Carboxylic Acids in Blakeslea trispora and Phycomyces blakesleeanus

    PubMed Central

    Kuzina, Vera; Cerdá-Olmedo, Enrique

    2006-01-01

    In Phycomyces blakesleeanus and Blakeslea trispora (order Mucorales, class Zygomycetes), sexual interaction on solid substrates leads to zygospore development and to increased carotene production (sexual carotenogenesis). Addition of small quantities of acetate, propionate, lactate, or leucine to mated cultures on minimal medium stimulated zygospore production and inhibited sexual carotenogenesis in both Phycomyces and Blakeslea. In Blakeslea, the threshold acetate concentration was <1 mmol/liter for both effects, and the concentrations that had one-half of the maximal effect were <2 mmol/liter for carotenogenesis and >7 mmol/liter for zygosporogenesis. The effects on Phycomyces were similar, but the concentrations of acetate had to be multiplied by ca. 3 to obtain the same results. Inhibition of sexual carotenogenesis by acetate occurred normally in Phycomyces mutants that cannot use acetate as a carbon source and in mutants whose dormant spores cannot be activated by acetate. Small carboxylic acids may be signals that, independent of their ability to trigger spore germination in Phycomyces, modify metabolism and development during the sexual cycle of Phycomyces and Blakeslea, uncoupling two processes that were thought to be linked and mediated by a common mechanism. PMID:16820488

  1. Inhibition of succinic acid production in metabolically engineered Escherichia coli by neutralizing agent, organic acids, and osmolarity.

    PubMed

    Andersson, Christian; Helmerius, Jonas; Hodge, David; Berglund, Kris A; Rova, Ulrika

    2009-01-01

    The economical viability of biochemical succinic acid production is a result of many processing parameters including final succinic acid concentration, recovery of succinate, and the volumetric productivity. Maintaining volumetric productivities >2.5 g L(-1) h(-1) is important if production of succinic acid from renewable resources should be competitive. In this work, the effects of organic acids, osmolarity, and neutralizing agent (NH4OH, KOH, NaOH, K2CO3, and Na2CO3), and Na2CO3) on the fermentative succinic acid production by Escherichia coli AFP184 were investigated. The highest concentration of succinic acid, 77 g L(-1), was obtained with Na2CO3. In general, irrespective of the base used, succinic acid productivity per viable cell was significantly reduced as the concentration of the produced acid increased. Increased osmolarity resulting from base addition during succinate production only marginally affected the productivity per viable cell. Addition of the osmoprotectant glycine betaine to cultures resulted in an increased aerobic growth rate and anaerobic glucose consumption rate, but decreased succinic acid yield. When using NH4OH productivity completely ceased at a succinic acid concentration of approximately 40 g L(-1). Volumetric productivities remained at 2.5 g L(-1) h(-1) for up to 10 h longer when K- or Na-bases where used instead of NH4OH. The decrease in cellular succinic acid productivity observed during the anaerobic phase was found to be due to increased organic acid concentrations rather than medium osmolarity.

  2. Study of the interaction of cadmium with membrane-bound succinate dehydrogenase.

    PubMed

    Jay, D; Zamorano, R; Muñoz, E; Gleason, R; Boldu, J L

    1991-04-01

    Cadmium ions inhibit membrane-bound succinate dehydrogenase with a second-order rate constant of 10.42 mM-1 s-1 at pH 7.35 and 25 degrees C. Succinate and malonate protect the enzyme against cadmium ion inhibition. The protection pattern exerted by succinate and malonate suggests that the group modified by cadmium is located at the active site. The pH curve of inactivation by Cd2+ indicates the involvement of an amino acid residue with pKa of 7.23.

  3. Succinate production from CO₂-grown microalgal biomass as carbon source using engineered Corynebacterium glutamicum through consolidated bioprocessing.

    PubMed

    Lee, Jungseok; Sim, Sang Jun; Bott, Michael; Um, Youngsoon; Oh, Min-Kyu; Woo, Han Min

    2014-07-24

    The potential for production of chemicals from microalgal biomass has been considered as an alternative route for CO₂ mitigation and establishment of biorefineries. This study presents the development of consolidated bioprocessing for succinate production from microalgal biomass using engineered Corynebacterium glutamicum. Starch-degrading and succinate-producing C. glutamicum strains produced succinate (0.16 g succinate/g total carbon source) from a mixture of starch and glucose as a model microalgal biomass. Subsequently, the engineered C. glutamicum strains were able to produce succinate (0.28 g succinate/g of total sugars including starch) from pretreated microalgal biomass of CO₂-grown Chlamydomonas reinhardtii. For the first time, this work shows succinate production from CO₂ via sequential fermentations of CO₂-grown microalgae and engineered C. glutamicum. Therefore, consolidated bioprocessing based on microalgal biomass could be useful to promote variety of biorefineries.

  4. Pretreatment of corn stover with diluted acetic acid for enhancement of acidogenic fermentation.

    PubMed

    Zhao, Xu; Wang, Lijuan; Lu, Xuebin; Zhang, Shuting

    2014-04-01

    A Box-Behnken design of response surface method was used to optimize acetic acid-catalyzed hydrothermal pretreatment of corn stover, in respect to acid concentration (0.05-0.25%), treatment time (5-15 min) and reaction temperature (180-210°C). Acidogenic fermentations with different initial pH and hydrolyzates were also measured to evaluate the optimal pretreatment conditions for maximizing acid production. The results showed that pretreatment with 0.25% acetic acid at 191°C for 7.74 min was found to be the most optimal condition for pretreatment of corn stover under which the production of acids can reach the highest level. Acidogenic fermentation with the hydrolyzate of pretreatment at the optimal condition at the initial pH=5 was shown to be butyric acid type fermentation, producing 21.84 g acetic acid, 7.246 g propionic acid, 9.170 butyric acid and 1.035 g isovaleric acid from 100g of corn stover in 900 g of water containing 2.25 g acetic acid.

  5. Cellulose esters synthesized using a tetrabutylammonium acetate and dimethylsulfoxide solvent system

    NASA Astrophysics Data System (ADS)

    Yu, Yongqi; Miao, Jiaojiao; Jiang, Zeming; Sun, Haibo; Zhang, Liping

    2016-07-01

    Cellulose acetate (CA) and cellulose acetate propionate (CAP) were homogeneously synthesized in a novel tetrabutylammonium acetate/dimethyl sulfoxide (DMSO) solvent system, without any catalyst, at temperatures below 70 °C. The molecular structures of the cellulose esters (CEs) and distributions of the substituents in the anhydroglucose repeating units were determined using 13C cross-polarization magic angle spinning nuclear magnetic resonance spectroscopy, and the degree of substitution (DS) values were determined using 1H nuclear magnetic resonance spectroscopy. The structures of the CEs, regenerated cellulose (RC), and pulp were determined using Fourier transform infrared spectroscopy. The thermal properties of the products were determined using thermogravimetric analysis. The temperatures of initial decomposition of the CEs were up to 40 °C higher than those of the RC and pulp. All the CEs were highly soluble in DMSO, but were insoluble in acetone. CAs with DS values less than 2.6 swelled or were poorly dissolved in CHCl3, but those with DS values above 2.9 dissolved rapidly. CAPs with DS values above 2.6 had good solubilities in ethyl acetate.

  6. Acidity and complex formation studies of 3-(adenine-9-yl)-propionic and 3-(thymine-1-yl)-propionic acids in ethanol-water media

    NASA Astrophysics Data System (ADS)

    Hammud, Hassan H.; El Shazly, Shawky; Sonji, Ghassan; Sonji, Nada; Bouhadir, Kamal H.

    2015-05-01

    The ligands 3-(adenine-9-yl)propionic acid (AA) and 3-(thymine-1-yl)propionic acid (TA) were prepared by N9-alkylation of adenine and N1-alkylation of thymine with ethylacrylate in presence of a base catalyst, followed by acid hydrolysis of the formed ethyl esters to give the corresponding propionic acid derivatives. The products were characterized by spectral methods (FTIR, 1H NMR and 13C NMR), which confirm their structures. The dissociation constants of ligands, were potentiometrically determined in 0.3 M KCl at 20-50 °C temperature range. The work was extended to study complexation behavior of AA and TA with various biologically important divalent metal ions (Co2+, Ni2+, Cu2+, Zn2+, Cd2+, Mn2+ and Pb2+) in 50% v/v water-ethanol medium at four different temperatures, keeping ionic strength constant (0.3 M KCl). The order of the stability constants of the formed complexes decreases in the sequence Cu2+ > Pb2+ > Zn2+ > Ni2+ > Co2+ > Mn2+ > Cd2+ for both ligands. The effect of temperature was also studied and the corresponding thermodynamic functions (ΔG, ΔH, ΔS) were derived and discussed. The formation of metal complexes has been found to be spontaneous, and the stability constants were dependant markedly on the basicity of the ligands.

  7. Importance of propionate for the repression of hepatic lipogenesis and improvement of insulin sensitivity in high‐fat diet‐induced obesity

    PubMed Central

    Weitkunat, Karolin; Schumann, Sara; Nickel, Daniela; Kappo, Katharina Antonia; Petzke, Klaus Jürgen; Kipp, Anna Patricia; Blaut, Michael

    2016-01-01

    1 Scope The SCFA acetate (Ac) and propionate (Pr) are major fermentation products of dietary fibers and provide additional energy to the host. We investigated short‐ and long‐term effects of dietary Ac and Pr supplementation on diet‐induced obesity and hepatic lipid metabolism. 2 Methods and results C3H/HeOuJ mice received high‐fat (HF) diets supplemented with 5% SCFA in different Ac:Pr ratios, a high acetate (HF‐HAc; 2.5:1 Ac:Pr) or high Pr ratio (HF‐HPr; 1:2.5 Ac:Pr) for 6 or 22 weeks. Control diets (low‐fat (LF), HF) contained no SCFA. SCFA did not affect body composition but reduced hepatic gene and protein expression of lipogenic enzymes leading to a reduced hepatic triglyceride concentration after 22 weeks in HF‐HPr mice. Analysis of long‐chain fatty acid composition (liver and plasma phospholipids) showed that supplementation of both ratios led to a lower ω6:ω3 ratio. Pr directly led to increased odd‐chain fatty acid (C15:0, C17:0) formation as confirmed in vitro using HepG2 cells. Remarkably, plasma C15:0 was correlated with the attenuation of HF diet‐induced insulin resistance. 3 Conclusion Dependent on the Ac:Pr ratio, especially odd‐chain fatty acid formation and insulin sensitivity are differentially affected, indicating the importance of Pr. PMID:27467905

  8. Some biochemical observations on gluconeogenesis from propionate in hepatocytes isolated from normal and biotin-deficients rats.

    PubMed

    Djabal, A; Mangeot, M; Cherruau, B; Lemonnier, A

    1985-01-01

    Propionate and pyruvate added to isolated normal and biotin-deficient adult rat hepatocytes increase the production of glucose. This production decreases about 30% on biotin deficiency. Malonate inhibits gluconeogenesis from propionate showing the metabolic transformation of propionyl-CoA via the Krebs cycle. Neither glucagon nor dibutyryl-cyclic AMP significantly stimulate gluconeogenesis.

  9. AB041. Effectiveness and cost impact evaluation of fluticasone propionate/formoterol compared to fluticasone propionate/salmeterol

    PubMed Central

    Ming, Simon Wan Yau; Small, Iain; Wolfe, Stephanie; Hamil, John; Gruffydd-Jones, Kevin; Daly, Cathal; Soriano, Joan B.; Gardner, Liz; Skinner, Derek; Price, David

    2016-01-01

    Background Treatment of asthmatics with an inhaled corticosteroid (ICS) and long-acting beta agonist (LABA) is recommended for maintenance treatment according to Step 3 in the GINA guidelines. Fixed-dose combination (FDC) inhalers simplify the dosing regimen and may improve adherence over their separate components. However, the effectiveness and cost impact of FDC devices containing fluticasone propionate/formoterol (FP/FOR) compared to fluticasone/salmeterol (FP/SAL) in asthma patients who initiate or switch to FDC ICS/LABA inhalers have not been studied in real-life patients in the United Kingdom. To determine whether FP/FOR is non-inferior to FP/SAL in patients who initiate or switch to a FDC ICS/LABA therapy with respect to decreasing the occurrence of asthma exacerbations and overall cost impact. Methods This study used a matched, historical cohort design to compare the two FDC ICS/LABA treatments using the Optimal Patient Care Database. Based on a 1-year exploratory analysis of baseline variables such as comorbidities, current treatment, demographics and clinical measurements, cohorts were matched to ensure similar patients were compared over a 1-year outcome. Two cohorts of patients were studied: one of patients initiated on combination therapy (either FP/FOR or FP/SAL) and one of patients either switched from FP/SAL to FP/FOR or who remained on FP/SAL. The primary outcome studied non-inferiority in terms of percentage of patients who were free from severe asthma exacerbations (defined by ATS/ERS position statements) for patients prescribed FP/FORversusFP/SAL in the outcome year. Secondary outcomes included the rate of asthma exacerbations, clinical exacerbations, asthma control, treatment stability, and lower respiratory tract hospitalisations. Cost impact outcomes included a comparison of resource costs, drug costs and combined drug and resource costs. Results The study included 2,472 patients (618 patients in FP/FOR and 1,854 patients in FP/SAL cohorts

  10. Quinone reduction by Rhodothermus marinus succinate:menaquinone oxidoreductase is not stimulated by the membrane potential

    SciTech Connect

    Fernandes, Andreia S.; Konstantinov, Alexander A.; Teixeira, Miguel; Pereira, Manuela M. . E-mail: mpereira@itqb.unl.pt

    2005-05-06

    Succinate:quinone oxidoreductase (SQR), a di-haem enzyme purified from Rhodothermus marinus, reveals an HQNO-sensitive succinate:quinone oxidoreductase activity with several menaquinone analogues as electron acceptors that decreases with lowering the redox midpoint potential of the quinones. A turnover with the low-potential 2,3-dimethyl-1,4-naphthoquinone that is the closest analogue of menaquinone, although low, can be detected in liposome-reconstituted SQR. Reduction of the quinone is not stimulated by an imposed K{sup +}-diffusion membrane potential of a physiological sign (positive inside the vesicles). Nor does the imposed membrane potential increase the reduction level of the haems in R. marinus SQR poised with the succinate/fumarate redox couple. The data do not support a widely discussed hypothesis on the electrogenic transmembrane electron transfer from succinate to menaquinone catalysed by di-haem SQRs. The role of the membrane potential in regulation of the SQR activity is discussed.

  11. Gut microbiota-produced succinate promotes C. difficile infection after antibiotic treatment or motility disturbance

    PubMed Central

    Ferreyra, Jessica A.; Wu, Katherine J.; Hryckowian, Andrew J.; Bouley, Donna M.; Weimer, Bart C.; Sonnenburg, Justin L.

    2016-01-01

    Summary Clostridium difficile is a leading cause of antibiotic-associated diarrhea. The mechanisms underlying C. difficile expansion after microbiota disturbance are just emerging. We assessed the gene expression profile of C. difficile within the intestine of gnotobiotic mice to identify genes regulated in response to either dietary or microbiota compositional changes. In the presence of the gut symbiont Bacteroides thetaiotaomicron, C. difficile induces a pathway that metabolizes the microbiota fermentation end-product succinate to butyrate. The low concentration of succinate in the microbiota of conventional mice is transiently elevated upon antibiotic treatment or chemically-induced intestinal motility disturbance, and C. difficile exploits this succinate spike to expand in the perturbed intestine. A C. difficile mutant compromised in succinate utilization is at a competitive disadvantage during these perturbations. Understanding the metabolic mechanisms involved in microbiota-C. difficile interactions may help to identify approaches for the treatment and prevention of C. difficile-associated diseases. PMID:25498344

  12. 21 CFR 172.765 - Succistearin (stearoyl propylene glycol hydrogen succinate).

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... additive is the reaction product of succinic anhydride, fully hydrogenated vegetable oil (predominantly C16... additive is used or intended for use as an emulsifier in or with shortenings and edible oils intended...

  13. 21 CFR 172.765 - Succistearin (stearoyl propylene glycol hydrogen succinate).

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... additive is the reaction product of succinic anhydride, fully hydrogenated vegetable oil (predominantly C16... additive is used or intended for use as an emulsifier in or with shortenings and edible oils intended...

  14. 21 CFR 172.765 - Succistearin (stearoyl propylene glycol hydrogen succinate).

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... additive is the reaction product of succinic anhydride, fully hydrogenated vegetable oil (predominantly C16... additive is used or intended for use as an emulsifier in or with shortenings and edible oils intended...

  15. 21 CFR 172.765 - Succistearin (stearoyl propylene glycol hydrogen succinate).

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... additive is the reaction product of succinic anhydride, fully hydrogenated vegetable oil (predominantly C16... additive is used or intended for use as an emulsifier in or with shortenings and edible oils intended...

  16. Succinate Dehydrogenase Supports Metabolic Repurposing of Mitochondria to Drive Inflammatory Macrophages.

    PubMed

    Mills, Evanna L; Kelly, Beth; Logan, Angela; Costa, Ana S H; Varma, Mukund; Bryant, Clare E; Tourlomousis, Panagiotis; Däbritz, J Henry M; Gottlieb, Eyal; Latorre, Isabel; Corr, Sinéad C; McManus, Gavin; Ryan, Dylan; Jacobs, Howard T; Szibor, Marten; Xavier, Ramnik J; Braun, Thomas; Frezza, Christian; Murphy, Michael P; O'Neill, Luke A

    2016-10-06

    Activated macrophages undergo metabolic reprogramming, which drives their pro-inflammatory phenotype, but the mechanistic basis for this remains obscure. Here, we demonstrate that upon lipopolysaccharide (LPS) stimulation, macrophages shift from producing ATP by oxidative phosphorylation to glycolysis while also increasing succinate levels. We show that increased mitochondrial oxidation of succinate via succinate dehydrogenase (SDH) and an elevation of mitochondrial membrane potential combine to drive mitochondrial reactive oxygen species (ROS) production. RNA sequencing reveals that this combination induces a pro-inflammatory gene expression profile, while an inhibitor of succinate oxidation, dimethyl malonate (DMM), promotes an anti-inflammatory outcome. Blocking ROS production with rotenone by uncoupling mitochondria or by expressing the alternative oxidase (AOX) inhibits this inflammatory phenotype, with AOX protecting mice from LPS lethality. The metabolic alterations that occur upon activation of macrophages therefore repurpose mitochondria from ATP synthesis to ROS production in order to promote a pro-inflammatory state.

  17. Succinate reverses in-vitro platelet inhibition by acetylsalicylic acid and P2Y receptor antagonists.

    PubMed

    Spath, Brigitte; Hansen, Arne; Bokemeyer, Carsten; Langer, Florian

    2012-01-01

    High on-treatment platelet reactivity has been associated with adverse cardiovascular events in patients receiving anti-platelet agents, but the molecular mechanisms underlying this phenomenon remain incompletely understood. Succinate, a citric acid cycle intermediate, is released into the circulation under conditions of mitochondrial dysfunction due to hypoxic organ damage, including sepsis, stroke, and myocardial infarction. Because the G protein-coupled receptor (GPCR) for succinate, SUCNR1 (GPR91), is present on human platelets, we hypothesized that succinate-mediated platelet stimulation may counteract the pharmacological effects of cyclooxygenase-1 and ADP receptor antagonists. To test this hypothesis in a controlled in-vitro study, washed platelets from healthy donors were treated with acetylsalicylic acid (ASA) or small-molecule P2Y(1) or P2Y(12) inhibitors and subsequently analyzed by light transmittance aggregometry using arachidonic acid (AA), ADP and succinate as platelet agonists. Aggregation in response to succinate alone was highly variable with only 29% of donors showing a (mostly delayed) platelet response. In contrast, succinate reproducibly and concentration-dependently (10-1000 µM) enhanced platelet aggregation in response to low concentrations of exogenous ADP. Furthermore, while succinate alone had no effect in the presence of platelet inhibitors, responsiveness of platelets to ADP after pretreatment with P2Y(1) or P2Y(12) antagonists was fully restored, when platelets were co-stimulated with 100 µM succinate. Similarly, succinate completely (at 1000 µM) or partially (at 100 µM) reversed the inhibitory effect of ASA on AA-induced platelet aggregation. In contrast, succinate failed to restore platelet responsiveness in the presence of both ASA and the P2Y(12) antagonist, suggesting that concomitant signaling via different GPCRs was required. Essentially identical results were obtained, when flow cytometric analysis of surface CD62P

  18. Industrial systems biology of Saccharomyces cerevisiae enables novel succinic acid cell factory.

    PubMed

    Otero, José Manuel; Cimini, Donatella; Patil, Kiran R; Poulsen, Simon G; Olsson, Lisbeth; Nielsen, Jens

    2013-01-01

    Saccharomyces cerevisiae is the most well characterized eukaryote, the preferred microbial cell factory for the largest industrial biotechnology product (bioethanol), and a robust commerically compatible scaffold to be exploitted for diverse chemical production. Succinic acid is a highly sought after added-value chemical for which there is no native pre-disposition for production and accmulation in S. cerevisiae. The genome-scale metabolic network reconstruction of S. cerevisiae enabled in silico gene deletion predictions using an evolutionary programming method to couple biomass and succinate production. Glycine and serine, both essential amino acids required for biomass formation, are formed from both glycolytic and TCA cycle intermediates. Succinate formation results from the isocitrate lyase catalyzed conversion of isocitrate, and from the α-keto-glutarate dehydrogenase catalyzed conversion of α-keto-glutarate. Succinate is subsequently depleted by the succinate dehydrogenase complex. The metabolic engineering strategy identified included deletion of the primary succinate consuming reaction, Sdh3p, and interruption of glycolysis derived serine by deletion of 3-phosphoglycerate dehydrogenase, Ser3p/Ser33p. Pursuing these targets, a multi-gene deletion strain was constructed, and directed evolution with selection used to identify a succinate producing mutant. Physiological characterization coupled with integrated data analysis of transcriptome data in the metabolically engineered strain were used to identify 2(nd)-round metabolic engineering targets. The resulting strain represents a 30-fold improvement in succinate titer, and a 43-fold improvement in succinate yield on biomass, with only a 2.8-fold decrease in the specific growth rate compared to the reference strain. Intuitive genetic targets for either over-expression or interruption of succinate producing or consuming pathways, respectively, do not lead to increased succinate. Rather, we demonstrate how

  19. Developmental Toxicity (Segment II) Study of WR238605 Succinate in Rats

    DTIC Science & Technology

    1994-11-04

    vehicle control or WR238605 Succinate treated groups. The use of Vitamin A (Retinol Palmitate) as a positive control agent was effective in producing a...ACCESSION NO. 073 [11. TITLE ( Include Security Classification) Developmental Toxicity (Segment II) Study of WR238605 Succinate in Rats ]\\2...ABSTRACT SECURITY CLASSIFICATION Unclassified i 22a. NAME OF RESPONSIBLE INDIVIDUAL Barrv S. IPvinP 22b. TELEPHONE ( Include Area Code) (312

  20. Succinate, an intermediate in metabolism, signal transduction, ROS, hypoxia, and tumorigenesis.

    PubMed

    Tretter, Laszlo; Patocs, Attila; Chinopoulos, Christos

    2016-08-01

    Succinate is an important metabolite at the cross-road of several metabolic pathways, also involved in the formation and elimination of reactive oxygen species. However, it is becoming increasingly apparent that its realm extends to epigenetics, tumorigenesis, signal transduction, endo- and paracrine modulation and inflammation. Here we review the pathways encompassing succinate as a metabolite or a signal and how these may interact in normal and pathological conditions.(1).

  1. Enrichment of 3-nitro-1-propionic acid-metabolizing bacteria in avian feces

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Denitrobacterium detoxificans is a Gram-positive anaerobe that conserves energy for growth exclusively via anaerobic respiration, oxidizing H2, formate or lactate for the reduction of nitrate, trimethylamine oxide, dimethyl sulfoxide or nitroalkanes such as 3-nitro-1-propionic acid (NPA). At presen...

  2. ANTIANDROGENIC EFFECTS OF VINCLOZOLIN ON MALE RATS ARE PARTIALLY ATTENUATED BY TESTOSTERONE PROPIONATE

    EPA Science Inventory

    ANTIANDROGENIC EFFECTS OF VINCLOZOLIN ON MALE RATS ARE PARTIALLY ATTENUATED BY TESTOSTERONE PROPIONATE

    Cynthia Wolf1,2 , Joe Ostby1, Jonathan Furr 1, Gerald A. LeBlanc2, and L. Earl Gray, Jr.1
    1 US Environmental Protection Agency, NHEERL, RTD, RTP, NC 27711, 2 Departmen...

  3. Phosphorus limitation strategy to increase propionic acid flux towards 3-hydroxyvaleric acid monomers in Cupriavidus necator.

    PubMed

    Grousseau, Estelle; Blanchet, Elise; Déléris, Stéphane; Albuquerque, Maria G E; Paul, Etienne; Uribelarrea, Jean-Louis

    2014-02-01

    Properties of polyhydroxybutyrate-co-hydroxyvalerate (P(3HB-co-3HV)) depend on their 3HV content. 3HV can be produced by Cupriavidus necator from propionic acid. Few studies explored carbon distribution and dynamics of 3HV and 3HB monomers production, and none of them have been done with phosphorus as limiting nutrient. In this study, fed-batch cultures of C. necator with propionic acid, as sole carbon source or mixed with butyric acid, were performed. Phosphorus deficiency allowed sustaining 3HV production rate and decreasing 3HB production rate, leading to an instant production of up to 100% of 3HV. When a residual growth is sustained by a phosphorus feeding, the maximum 3HV percentage produced from propionic acid is limited to 33% (Mole.Mole(-1)). The association of a second carbon source like butyric acid lead to higher conversion of propionic acid into 3HV. This study showed the importance of the limiting nutrient and of the culture strategy to get the appropriate product.

  4. MASCULINIZATION OF FEMALE RATS BY PRENATAL TESTOSTERONE PROPIONATE IS PARTIALLY ATTENUATED BY VINCLOZOLIN

    EPA Science Inventory

    MASCULINIZATION OF FEMALE RATS BY PRENATAL TESTOSTERONE PROPIONATE IS PARTIALLY ATTENUATED BY VINCLOZOLIN
    Cynthia Wolf1,2, Gerald LeBlanc2, Andrew Hotchkiss3, Jonathan Furr1, L Earl Gray, Jr.1
    1USEPA, Reproductive Toxicology Division, RTP, NC 27711, 2Dept. Molecular and En...

  5. Double-blind, crossover, placebo-controlled clinical trial with clobetasol propionate in desquamative gingivitis.

    PubMed

    Motta, Ana Carolina Fragoso; Domaneschi, Carina; Komesu, Marilena Chinali; Souza, Cacilda da Silva; Aoki, Valéria; Migliari, Dante Antonio

    2009-01-01

    The aim of this study was to evaluate the efficacy of a 0.05% clobetasol propionate ointment administered in trays to 22 patients with desquamative gingivitis in a double-blind, crossover, placebo-controlled trial. Patients received container number 1 and were instructed to apply the ointment 3 times a day for 2 weeks, and to reduce the application to once a day in the third week. Next, the patients were then instructed to discontinue the treatment for 2 weeks, and were then given container 2, used in the same way and for the same length of time as container 1. Regarding signs, 17 patients presented some improvement, while 5 experienced worsening with clobetasol propionate. With the placebo, 14 patients presented some improvement, and 8 patients presented worsening. For symptoms, there was complete improvement in 2 patients, partial improvement in 12, no response in 7, and worsening in 1 with clobetasol propionate. With the placebo, there was partial improvement in 8 patients, no response in 12 and worsening in 2. No statistically significant difference was found between clobetasol and placebo (p>0.05). Within the period designed to treat the gingival lesions of the patients, clobetasol propionate did not significantly outperform the placebo.

  6. 2(2,4,5-Trichlorophenoxy) propionic acid (2,4,5-TP)

    Integrated Risk Information System (IRIS)

    2 ( 2,4,5 - Trichlorophenoxy ) propionic acid ( 2,4,5 - TP ) ; CASRN 93 - 72 - 1 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Hea

  7. Novel Characteristics of Succinate Coenzyme A (Succinate-CoA) Ligases: Conversion of Malate to Malyl-CoA and CoA-Thioester Formation of Succinate Analogues In Vitro

    PubMed Central

    Nolte, Johannes Christoph; Schürmann, Marc; Schepers, Catherine-Louise; Vogel, Elvira; Wübbeler, Jan Hendrik

    2014-01-01

    Three succinate coenzyme A (succinate-CoA) ligases (SucCD) from Escherichia coli, Advenella mimigardefordensis DPN7T, and Alcanivorax borkumensis SK2 were characterized regarding their substrate specificity concerning succinate analogues. Previous studies had suggested that SucCD enzymes might be promiscuous toward succinate analogues, such as itaconate and 3-sulfinopropionate (3SP). The latter is an intermediate of the degradation pathway of 3,3′-dithiodipropionate (DTDP), a precursor for the biotechnical production of polythioesters (PTEs) in bacteria. The sucCD genes were expressed in E. coli BL21(DE3)/pLysS. The SucCD enzymes of E. coli and A. mimigardefordensis DPN7T were purified in the native state using stepwise purification protocols, while SucCD from A. borkumensis SK2 was equipped with a C-terminal hexahistidine tag at the SucD subunit. Besides the preference for the physiological substrates succinate, itaconate, ATP, and CoA, high enzyme activity was additionally determined for both enantiomeric forms of malate, amounting to 10 to 21% of the activity with succinate. Km values ranged from 2.5 to 3.6 mM for l-malate and from 3.6 to 4.2 mM for d-malate for the SucCD enzymes investigated in this study. As l-malate-CoA ligase is present in the serine cycle for assimilation of C1 compounds in methylotrophs, structural comparison of these two enzymes as members of the same subsubclass suggested a strong resemblance of SucCD to l-malate-CoA ligase and gave rise to the speculation that malate-CoA ligases and succinate-CoA ligases have the same evolutionary origin. Although enzyme activities were very low for the additional substrates investigated, liquid chromatography/electrospray ionization-mass spectrometry analyses proved the ability of SucCD enzymes to form CoA-thioesters of adipate, glutarate, and fumarate. Since all SucCD enzymes were able to activate 3SP to 3SP-CoA, we consequently demonstrated that the activation of 3SP is not a unique characteristic

  8. Improving succinic acid production by Actinobacillus succinogenes from raw industrial carob pods.

    PubMed

    Carvalho, Margarida; Roca, Christophe; Reis, Maria A M

    2016-10-01

    Carob pods are an inexpensive by-product of locust bean gum industry that can be used as renewable feedstock for bio-based succinic acid. Here, for the first time, unprocessed raw carob pods were used to extract a highly enriched sugar solution, afterwards used as substrate to produce succinic acid using Actinobacillus succinogenes. Batch fermentations containing 30g/L sugars resulted in a production rate of 1.67gSA/L.h and a yield of 0.39gSA/g sugars. Taking advantage of A. succinogenes' metabolism, uncoupling cell growth from succinic acid production, a fed-batch mode was implemented to increase succinic acid yield and reduce by-products formation. This strategy resulted in a succinic acid yield of 0.94gSA/g sugars, the highest yield reported in the literature for fed-batch and continuous experiments, while maintaining by-products at residual values. Results demonstrate that raw carob pods are a highly efficient feedstock for bio-based succinic acid production.

  9. Ginsenoside Rg5 Inhibits Succinate-Associated Lipolysis in Adipose Tissue and Prevents Muscle Insulin Resistance

    PubMed Central

    Xiao, Na; Yang, Le-Le; Yang, Yi-Lin; Liu, Li-Wei; Li, Jia; Liu, Baolin; Liu, Kang; Qi, Lian-Wen; Li, Ping

    2017-01-01

    Endoplasmic reticulum (ER) stress, inflammation, and lipolysis occur simultaneously in adipose dysfunction and contribute to insulin resistance. This study was designed to investigate whether ginsenoside Rg5 could ameliorate adipose dysfunction and prevent muscle insulin resistance. Short-term high-fat diet (HFD) feeding induced hypoxia with ER stress in adipose tissue, leading to succinate accumulation due to the reversal of succinate dehydrogenase (SDH) activity. Rg5 treatment reduced cellular energy charge, suppressed ER stress and then prevented succinate accumulation in adipose tissue. Succinate promoted IL-1β production through NLRP3 inflammasome activation and then increased cAMP accumulation by impairing PDE3B expression, leading to increased lipolysis. Ginsenoside Rg5 treatment suppressed NLRP3 inflammasome activation, preserved PDE3B expression and then reduced cAMP accumulation, contributing to inhibition of lipolysis. Adipose lipolysis increased FFAs trafficking from adipose tissue to muscle. Rg5 reduced diacylglycerol (DAG) and ceramides accumulation, inhibited protein kinase Cθ translocation, and prevented insulin resistance in muscle. In conclusion, succinate accumulation in hypoxic adipose tissue acts as a metabolic signaling to link ER stress, inflammation and cAMP/PKA activation, contributing to lipolysis and insulin resistance. These findings establish a previously unrecognized role of ginsenosides in the regulation of lipid and glucose homeostasis and suggest that adipose succinate-associated NLRP3 inflammasome activation might be targeted therapeutically to prevent lipolysis and insulin resistance. PMID:28261091

  10. Production of succinic acid from oil palm empty fruit bunch cellulose using Actinobacillus succinogenes

    NASA Astrophysics Data System (ADS)

    Pasma, Satriani Aga; Daik, Rusli; Maskat, Mohamad Yusof

    2013-11-01

    Succinic acid is a common metabolite in plants, animals and microorganisms. It has been used widely in agricultural, food and pharmaceutical industries. Enzymatic hydrolysate glucose from oil palm empty fruit bunch (OPEFB) cellulose was used as a substrate for succinic acid production using Actinobacillus succinogenes. Using cellulose extraction from OPEFB can enhance the production of glucose as a main substrate for succinic acid production. The highest concentration of glucose produced from enzymatic hydrolysis is 167 mg/mL and the sugar recovery is 0.73 g/g of OPEFB. By optimizing the culture medium for succinic acid fermentation with enzymatic hydrolysate of OPEFB cellulose, the nitrogen sources could be reduced to just only 2.5 g yeast extract and 2.5 g corn step liquor. Batch fermentation was carried out using enzymatic hydrolysate of OPEFB cellulose with yeast extract, corn steep liquor and the salts mixture, 23.5 g/L succinic acid was obtained with consumption of 72 g/L glucose in enzymatic hydrolysate of OPEFB cellulose at 38 hours and 37°C. This study suggests that enzymatic hydrolysate of OPEFB cellulose maybe an alternative substrate for the efficient production of succinic acid by Actinobacillus succinogenes.

  11. Absorbance correction method for estimation of telmisartan and metoprolol succinate in combined tablet dosage forms

    PubMed Central

    Patel, Komal; Patel, Amit; Dave, Jayant; Patel, Chaganbhai

    2012-01-01

    Aim and Background: The present manuscript describes simple, sensitive, rapid, accurate, precise and economical spectrophotometric method for the simultaneous determination of telmisartan and metoprolol succinate in combined tablet dosage form. Materials and Methods: The method is based on the absorbance correction equations for analysis of both the drugs using methanol as solvent. Telmisartan has absorbance maxima at 296 nm and metoprolol succinate has absorbance maxima at 223 nm in methanol. The linearity was obtained in the concentration range of 2-16 μg/ ml and 3-24 μg/ml for telmisartan and metoprolol succinate, respectively. The concentrations of the drugs were determined by using absorbance correction method at both the wavelengths. The method was successfully applied to pharmaceutical dosage form because no interference from the tablet excipients was found. The suitability of this method for the quantitative determination of telmisartan and metoprolol succinate was proved by validation. The proposed method was found to be simple and sensitive for the quality control application of telmisartan and metoprolol succinate in pharmaceutical dosage form. Result: The result of analysis has been validated statistically and by recovery studies. Recoveries were found in the range of 98.08-100.55% of telmisartan and 98.41-101.87% of metoprolol succinate. PMID:23781489

  12. Immobilization of Actinobacillus succinogenes by adhesion or entrapment for the production of succinic acid.

    PubMed

    Corona-González, Rosa Isela; Miramontes-Murillo, Ricardo; Arriola-Guevara, Enrique; Guatemala-Morales, Guadalupe; Toriz, Guillermo; Pelayo-Ortiz, Carlos

    2014-07-01

    The production of succinic acid was studied with entrapped and adsorbed Actinobacillus succinogenes. The adsorption of fermentation products (organic acids in the concentration range of 1-20 g/L) on different supports was evaluated. It was found that succinic acid was adsorbed in small quantities on diatomite and zeolite (12.6 mg/g support). The highest production of succinic acid was achieved with A. succinogenes entrapped in agar beads. Batch fermentations with immobilized cells were carried out with glucose concentrations ranging from 20 to 80 g/L. Succinic acid (43.4 g/L) was obtained from 78.3g/L glucose, and a high productivity (2.83 g/Lh) was obtained with a glucose concentration of 37.6g/L. For repeated batch fermentations (5 cycles in 72 h) with immobilized cells in agar, the total glucose consumed was 147.55 g/L, while the production of succinic acid was 107 g/L. Immobilized cells reduced significantly the fermentation time, yield, productivity and final concentration of succinic acid.

  13. Biotechnological route for sustainable succinate production utilizing oil palm frond and kenaf as potential carbon sources.

    PubMed

    Luthfi, Abdullah Amru Indera; Manaf, Shareena Fairuz Abdul; Illias, Rosli Md; Harun, Shuhaida; Mohammad, Abdul Wahab; Jahim, Jamaliah Md

    2017-04-01

    Due to the world's dwindling energy supplies, greater thrust has been placed on the utilization of renewable resources for global succinate production. Exploration of such biotechnological route could be seen as an act of counterbalance to the continued fossil fuel dominance. Malaysia being a tropical country stands out among many other nations for its plenty of resources in the form of lignocellulosic biomass. To date, oil palm frond (OPF) contributes to the largest fraction of agricultural residues in Malaysia, while kenaf, a newly introduced fiber crop with relatively high growth rate, holds great potential for developing sustainable succinate production, apart from OPF. Utilization of non-food, inexhaustible, and low-cost derived biomass in the form of OPF and kenaf for bio-based succinate production remains largely untapped. Owing to the richness of carbohydrates in OPF and kenaf, bio-succinate commercialization using these sources appears as an attractive proposition for future sustainable developments. The aim of this paper was to review some research efforts in developing a biorefinery system based on OPF and kenaf as processing inputs. It presents the importance of the current progress in bio-succinate commercialization, in addition to describing the potential use of different succinate production hosts and various pretreatments-saccharifications under development for OPF and kenaf. Evaluations on the feasibility of OPF and kenaf as fermentation substrates are also discussed.

  14. Methodological problems in the histochemical demonstration of succinate semialdehyde dehydrogenase activity.

    PubMed

    Bernocchi, G; Barni, S

    1983-12-01

    Methodological aspects of the histochemical technique for the demonstration of succinate semialdehyde dehydrogenase activity (EC 1.2.1.24) (indicative of the degradative step of gamma-aminobutyric acid catabolism) have been analysed in rat Purkinje neurons, where gamma-aminobutyric acid has been shown to be a neurotransmitter, and in hepatocytes, where it is metabolized. During a histochemical incubation for the enzyme, artefacts of succinate dehydrogenase activity and the 'nothing dehydrogenase' reaction are produced. Inhibition of these artefacts by the addition of two inhibitors, malonate and p-hydroxybenzaldehyde, revealed specific reaction products. Formazan granules, which can be ascribed only to specific succinate semialdehyde dehydrogenase activity, are obtained by adding malonate to the incubation medium in order to inhibit both succinate dehydrogenase activity and nothing dehydrogenase. The formation of these granules is completely inhibited by p-hydroxybenzaldehyde, an inhibitor of succinate semialdehyde dehydrogenase activity. Different levels of succinate semialdehyde dehydrogenase activity were noted in Purkinje neurons. This activity was also found in hepatocytes, mostly in the portal area, but with a lesser degree of intensity and specificity. Indeed, non-specific formazan granules were still produced, because of the 'nothing dehydrogenase' reaction, even in the presence of malonate. Thus, a malonate-insensitive 'nothing dehydrogenase' reaction seems to be present in neural and hepatic tissues.

  15. The role of succinate in the respiratory chain of Trypanosoma brucei procyclic trypomastigotes.

    PubMed

    Turrens, J F

    1989-04-15

    Trypanosoma brucei procyclic trypomastigotes were made permeable by using digitonin (0-70 micrograms/mg of protein). This procedure allowed exposure of coupled mitochondria to different substrates. Only succinate and glycerol phosphate (but not NADH-dependent substrates) were capable of stimulating oxygen consumption. Fluorescence studies on intact cells indicated that addition of succinate stimulates NAD(P)H oxidation, contrary to what happens in mammalian mitochondria. Addition of malonate, an inhibitor of succinate dehydrogenase, stimulated NAD(P)H reduction. Malonate also inhibited intact-cell respiration and motility, both of which were restored by further addition of succinate. Experiments carried out with isolated mitochondrial membranes showed that, although the electron transfer from succinate to cytochrome c was inhibitable by antimycin, NADH-cytochrome c reductase was antimycin-insensitive. We postulate that the NADH-ubiquinone segment of the respiratory chain is replaced by NADH-fumarate reductase, which reoxidizes the mitochondrial NADH and in turn generates succinate for the respiratory chain. This hypothesis is further supported by the inhibitory effect on cell growth and respiration of 3-methoxyphenylacetic acid, an inhibitor of the NADH-fumarate reductase of T. brucei.

  16. Interaction of the membrane-bound succinate dehydrogenase with substrate and competitive inhibitors.

    PubMed

    Kotlyar, A B; Vinogradov, A D

    1984-01-18

    The protective effect of dicarboxylates on the active-site-directed inhibition of the membrane-bound succinate dehydrogenase by N-ethylmaleimide, steady-state kinetics methods for Ki and Ks determinations, and equilibrium studies were employed to quantitate the relative affinities of succinate, fumarate, malonate and oxaloacetate to the reduced and oxidized species of the enzyme. A more than 10-fold difference in the relative affinities of the reduced and oxidized succinate dehydrogenase to succinate, fumarate and oxaloacetate is found, whereas the reactivity of the active-site sulphydryl group does not depend on the redox state of the enzyme. The redox-state-dependent changes in the affinity of the membrane-bound succinate dehydrogenase to oxaloacetate can be quantitatively accounted for by a 10-fold increase in the rate of dissociation of the enzyme-inhibitor complex which occurs upon reduction of the enzyme. The data obtained give no support for either the existence of a sulphydryl group other than the active-site one important for the catalysis or for the presence of a separate dicarboxylate-specific regulatory site in the succinate dehydrogenase molecule.

  17. A statistical method for enhancing the production of succinic acid from Escherichia coli under anaerobic conditions.

    PubMed

    Isar, Jasmine; Agarwal, Lata; Saran, Saurabh; Saxena, Rajendra Kumar

    2006-09-01

    The most influential parameters for succinic acid production obtained through one at a time method were sucrose, tryptone, magnesium carbonate, inoculum size and incubation period. These resulted in the production of 7.0 g L(-1) of succinic acid in 60 h from Escherichia coli W3110 under anaerobic conditions. Based on these results, a statistical method, face centered central composite design (FCCCD) falling under response surface method (RSM) was employed for further enhancing the succinic acid production and to monitor the interactive effect of these parameters, which resulted in a twofold increase in yield (14.3 g L(-1) in 48 h). The analysis of variance (ANOVA) showed the adequacy of the model and the verification experiments confirmed its validity. On subsequent scale-up in a 10-L bioreactor using conditions optimized through RSM, 24.2 g L(-1) of succinic acid was obtained in 30 h. This clearly indicated that the model stood valid even on large-scale. Thus, the statistical optimization strategy led to a 3.5-fold increase in the yield of succinic acid. This is the first report on the use of FCCCD to improve succinic acid production from E. coli.

  18. Localization of the succinate receptor in the distal nephron and its signaling in polarized MDCK cells.

    PubMed

    Robben, Joris H; Fenton, Robert A; Vargas, Sarah L; Schweer, Horst; Peti-Peterdi, Janos; Deen, Peter M T; Milligan, Graeme

    2009-12-01

    When the succinate receptor (SUCNR1) is activated in the afferent arterioles of the glomerulus it increases renin release and induces hypertension. To study its location in other nephron segments and its role in kidney function, we performed immunohistochemical analysis and found that SUCNR1 is located in the luminal membrane of macula densa cells of the juxtaglomerular apparatus in close proximity to renin-producing granular cells, the cortical thick ascending limb, and cortical and inner medullary collecting duct cells. In order to study its signaling, SUCNR1 was stably expressed in Madin-Darby Canine Kidney (MDCK) cells, where it localized to the apical membrane. Activation of the cells by succinate caused Gq and Gi-mediated intracellular calcium mobilization, transient phosphorylation of extracellular regulated kinase (ERK)1/2 and the release of arachidonic acid along with prostaglandins E2 and I2. Signaling was desensitized without receptor internalization but rapidly resensitized upon succinate removal. Immunohistochemical evidence of phosphorylated ERK1/2 was found in cortical collecting duct cells of wild type but not SUCNR1 knockout streptozotocin-induced diabetic mice, indicating in vivo relevance. Since urinary succinate concentrations in health and disease are in the activation range of the SUCNR1, this receptor can sense succinate in the luminal fluid. Our study suggests that changes in the luminal succinate concentration may regulate several aspects of renal function.

  19. [Optimization of succinic acid fermentation with Actinobacillus succinogenes by response surface methodology].

    PubMed

    Shen, Naikun; Qin, Yan; Wang, Qingyan; Xie, Nengzhong; Mi, Huizhi; Zhu, Qixia; Liao, Siming; Huang, Ribo

    2013-10-01

    Succinic acid is an important C4 platform chemical in the synthesis of many commodity and special chemicals. In the present work, different compounds were evaluated for succinic acid production by Actinobacillus succinogenes GXAS 137. Important parameters were screened by the single factor experiment and Plackeet-Burman design. Subsequently, the highest production of succinic acid was approached by the path of steepest ascent. Then, the optimum values of the parameters were obtained by Box-Behnken design. The results show that the important parameters were glucose, yeast extract and MgCO3 concentrations. The optimum condition was as follows (g/L): glucose 70.00, yeast extract 9.20 and MgCO3 58.10. Succinic acid yield reached 47.64 g/L at the optimal condition. Succinic acid increased by 29.14% than that before the optimization (36.89 g/L). Response surface methodology was proven to be a powerful tool to optimize succinic acid production.

  20. Effect of succinate sodium on the metmyoglobin reduction and color stability of beef patties.

    PubMed

    Zhu, Jinyuan; Liu, Fang; Li, Xingmin; Dai, Ruitong

    2009-07-08

    In two experiments, the effect of succinate sodium on the metmyoglobin (MetMb) reduction and color stability of beef patties was investigated. In experiment 1, the ground-beef strip loins (longissimus dorsi muscle) were blended with different concentrations of succinate. Enhancing patties with 6 mM succinate significantly increased the MetMb-reducing ability and subsequent color stability during storage. In experiment 2, MetMb and different concentrations of succinate, lactate, and reduced nicotinamide adenine dinucleotide (NADH) were incubated with mitochondria, and their effect on meat MetMb reduction was investigated. Increasing the concentration of NADH and lactate increased MetMb reduction, but only succinate of 16 and 24 mM significantly decreased the relative MetMb percentage compared to other systems. This indicate that there are no significant differences between aerobic and anaerobic MetMb-reducing activities. In comparison to the systems of NADH-MetMb reduction (including the systems of lactate-MetMb reduction), the succinate-MetMb reduction systems are more stable and less affected by oxygen. More identification work is needed to obtain the more complete pathways on MetMb reduction.

  1. Succinic acid production by Actinobacillus succinogenes using hydrolysates of spent yeast cells and corn fiber.

    PubMed

    Chen, Ke-Quan; Li, Jian; Ma, Jiang-Feng; Jiang, Min; Wei, Ping; Liu, Zhong-Min; Ying, Han-Jie

    2011-01-01

    The enzymatic hydrolysate of spent yeast cells was evaluated as a nitrogen source for succinic acid production by Actinobacillus succinogenes NJ113, using corn fiber hydrolysate as a carbon source. When spent yeast cell hydrolysate was used directly as a nitrogen source, a maximum succinic acid concentration of 35.5 g/l was obtained from a glucose concentration of 50 g/l, with a glucose utilization of 95.2%. Supplementation with individual vitamins showed that biotin was the most likely factor to be limiting for succinic acid production with spent yeast cell hydrolysate. After supplementing spent yeast cell hydrolysate and 90 g/l of glucose with 150 μg/l of biotin, cell growth increased 32.5%, glucose utilization increased 37.6%, and succinic acid concentration was enhanced 49.0%. As a result, when biotin-supplemented spent yeast cell hydrolysate was used with corn fiber hydrolysate, a succinic acid yield of 67.7% was obtained from 70.3 g/l of total sugar concentration, with a productivity of 0.63 g/(l h). Our results suggest that biotin-supplemented spent yeast cell hydrolysate may be an alternative nitrogen source for the efficient production of succinic acid by A. succinogenes NJ113, using renewable resources.

  2. Systemic exposure and urinary cortisol effects of fluticasone propionate formulated with hydrofluoroalkane in 4- to 11-year-olds with asthma.

    PubMed

    Kim, Kenneth T; Milgrom, Henry; Yoon, Y Kellie; Levy, Arden L; Matz, Paul; Welch, Michael J; Cahn, Anthony; Collins, David A; Kathman, Steven; Mehta, Rashmi; Su, Sheng-Fang; Kunka, Robert L

    2008-01-01

    The systemic exposure of fluticasone propionate with hydrofluoroalkane propellant compared with chlorofluoro-carbon propellant and the effect of fluticasone propionate hydrofluoroalkane on 24-hour urinary cortisol in children aged 4 to 11 years with asthma were evaluated. Study 1 was an open-label, 2-way crossover study in which 16 subjects were randomized to 7.5 days each of fluticasone propionate hydrofluoroalkane 88 mug twice a day or fluticasone propionate chlorofluorocarbon 88 mug twice a day. In study 2, 63 subjects received 13.5 days of placebo followed by 27.5 days of fluticasone propionate hydrofluoroalkane 88 mug twice a day. The main outcome measure for study 1 was the difference between fluticasone propionate hydrofluoroalkane and fluticasone propionate chlorofluorocarbon in fluticasone propionate AUC(last) (area under the plasma fluticasone propionate concentration-time curve from zero up to the last quantifiable plasma concentration), and for study 2, 24-hour overnight urinary cortisol excretion. In study 1, fluticasone propionate systemic exposure was significantly lower (55%) with hydrofluoroalkane metered dose inhaler compared with chlorofluorocarbon metered dose inhaler. Study 2 showed no statistically significant changes in 24-hour overnight urinary cortisol excretion and no relationship to fluticasone propionate systemic exposure at this dose. The results of these 2 studies showed that in children aged 4 to 11 years with asthma, fluticasone propionate hydrofluoroalkane has lower systemic exposure compared with chlorofluorocarbon and no hypothalamic-pituitary-adrenal axis effects as measured by 24-hour urinary cortisol excretion.

  3. A 3-(3-hydroxyphenyl)propionic acid catabolic pathway in Rhodococcus globerulus PWD1: cloning and characterization of the hpp operon.

    PubMed Central

    Barnes, M R; Duetz, W A; Williams, P A

    1997-01-01

    Rhodococcus globerulus PWD1, a soil isolate from a polluted site in The Netherlands, is able to degrade a broad range of aromatic compounds. A novel gene cluster which appears to encode a pathway for the degradation of phenolic acids such as 3-(3-hydroxyphenyl)propionate (3HPP) has been cloned from the chromosome of this organism. Sequence analysis of a 7-kb region identified five open reading frames (ORFs). Analysis of mRNA showed that the genes were expressed during growth on 3HPP and 3-hydroxyphenylacetate (3HPA) but not during growth on m-cresol or succinate. The first ORF, hppA, which appears to be separately transcribed, had considerable amino acid identity with a number of hydroxylases. Transcriptional analysis indicates that the next four ORFs, hppCBKR, which are tightly clustered, constitute a single operon. These genes appear to encode a hydroxymuconic semialdehyde hydrolase (HppC), an extradiol dioxygenase (HppB), a membrane transport protein (HppK), and a member of the IclR family of regulatory proteins (HppR). The activities of HppB and HppC have been confirmed by enzyme assay of Escherichia coli hosts. The substrate specificity of HppB expressed from the cloned gene matches that of the meta-cleavage dioxygenase expressed from wild-type Rhodococcus grown on both 3HPP and 3HPA and is considerably more active against acid than against neutral catechols. The deduced amino acid sequences of the gene products have a recognizable homology with a broad range of enzymes and proteins involved in biodegradation and appear most similar to the mhp operon from E. coli K-12, which also encodes the degradation of 3HPP. PMID:9324265

  4. Radioprotective properties of tocopherol succinate against ionizing radiation in mice

    PubMed Central

    Singh, Vijay K.; Singh, Pankaj K.; Wise, Stephen Y.; Posarac, Ana; Fatanmi, Oluseyi O.

    2013-01-01

    Threats of nuclear and other radiologic exposures have been increasing but no countermeasure for acute radiation syndrome has been approved by regulatory authorities. In prior publications we have demonstrated the efficacy of tocopherol succinate (TS) as a promising radiation countermeasure with the potential to protect against lethal doses of ionizing radiation exposure. The aim of this study was to gain further insight regarding how TS protects mice against a lethal dose of radiation. CD2F1 mice were injected subcutaneously with 400 mg/kg of TS, and 24 h later exposed to 60Co γ–radiation. Intestinal tissues or spleen/thymus were harvested after irradiation and analyzed for CD68-positive inflammatory cells and apoptotic cells by immunostaining of jejunal cross-sections. Comet assay was used to analyze DNA damage in various tissues. Phospho-histone H3(pH3) and the proliferating cell nuclear antigen (PCNA) were used as mitotic markers for immunostaining jejunal cross-sections. We observed that injecting TS significantly decreased the number of CD68-positive cells, DNA damage and apoptotic cells (BAX, caspase 3 and cleaved poly(ADP-ribose) polymerase-positive cells) as judged by various apoptotic pathway markers. TS treatment also increased proliferating cells in irradiated mice. Results of this study further support our contention that TS protects mice against lethal doses of ionizing radiation by inhibiting radiation-induced apoptosis and DNA damage while enhancing cell proliferation. PMID:23038797

  5. Incidence and Geographic Distribution of Succinic Semialdehyde Dehydrogenase (SSADH) Deficiency.

    PubMed

    Attri, Savita Verma; Singhi, Pratibha; Wiwattanadittakul, Natrujee; Goswami, Jyotindra N; Sankhyan, Naveen; Salomons, Gajja S; Roullett, Jean-Baptiste; Hodgeman, Ryan; Parviz, Mahsa; Gibson, K Michael; Pearl, Phillip L

    2016-11-05

    The incidence of succinic semialdehyde dehydrogenase (SSADH) deficiency, an autosomal recessive inherited disorder of GABA degradation, is unknown. Upon a recent diagnosis of a new family of affected fraternal twins from the Punjabi ethnic group of India, case ascertainment from the literature and our database was done to determine the number of confirmed cases along with their geographic distribution. The probands presented with global developmental delay, infantile onset epilepsy, and a persistent neurodevelopmental disorder upon diagnosis at 10 years of age with intellectual disability, expressive aphasia, and behavioral problems most prominent for hyperactivity. Gamma-hydroxybutyric aciduria and homozygous ALDH5A1 c.608C>T; p.Pro203Leu mutations were confirmed. Identification of all available individual cases with clinical details available including geographic or ethnic origin revealed 182 patients from 40 countries, with the largest number of patients reported from the USA (24%), Turkey (10%), China (7%), Saudi Arabia (6%), and Germany (5%). This study provides an accounting of all published cases of confirmed SSADH deficiency and provides data useful in planning further studies of this rare inborn error of metabolism.

  6. Natural history of succinic semialdehyde dehydrogenase deficiency through adulthood

    PubMed Central

    Lewis, Evan Cole; De Meulemeester, Christine; Chakraborty, Pranesh; Gibson, K. Michael; Torres, Carlos; Guberman, Alan; Salomons, Gajja S.; Jakobs, Cornelis; Ali-Ridha, Andre; Parviz, Mahsa; Pearl, Phillip L.

    2015-01-01

    Objective: The natural history of succinic semialdehyde dehydrogenase (SSADH) deficiency in adulthood is unknown; we elucidate the clinical manifestations of the disease later in life. Methods: A 63-year-old man with long-standing intellectual disability was diagnosed with SSADH deficiency following hospitalization for progressive decline, escalating seizures, and prolonged periods of altered consciousness. We present a detailed review of his clinical course and reviewed our SSADH deficiency database adult cohort to derive natural history information. Results: Of 95 patients in the database for whom age at diagnosis is recorded, there are 40 individuals currently aged 18 years or older. Only 3 patients were diagnosed after age 18 years. Of 25 adults for whom data are available after age 18, 60% have a history of epilepsy. Predominant seizure types are generalized tonic-clonic, absence, and myoclonic. EEGs showed background slowing or generalized epileptiform discharges in two-thirds of adults for whom EEG data were collected. History of psychiatric symptoms was prominent, with frequent anxiety, sleep disturbances, and obsessive-compulsive disorder. Conclusions: We identified patients older than 18 years with SSADH deficiency in our database following identification and review of a patient diagnosed in the seventh decade of life. The illness had a progressive course with escalating seizures in the index case, with fatality at age 63. Diagnosis in adulthood is rare. Epilepsy is more common in the adult than the pediatric SSADH deficiency cohort; neuropsychiatric morbidity remains prominent. PMID:26268900

  7. Succinic semialdehyde dehydrogenase deficiency: lessons from mice and men.

    PubMed

    Pearl, P L; Gibson, K M; Cortez, M A; Wu, Y; Carter Snead, O; Knerr, I; Forester, K; Pettiford, J M; Jakobs, C; Theodore, W H

    2009-06-01

    Succinic semialdehyde dehydrogenase (SSADH) deficiency, a disorder of GABA degradation with subsequent elevations in brain GABA and GHB, is a neurometabolic disorder with intellectual disability, epilepsy, hypotonia, ataxia, sleep disorders, and psychiatric disturbances. Neuroimaging reveals increased T2-weighted MRI signal usually affecting the globus pallidus, cerebellar dentate nucleus, and subthalamic nucleus, and often cerebral and cerebellar atrophy. EEG abnormalities are usually generalized spike-wave, consistent with a predilection for generalized epilepsy. The murine phenotype is characterized by failure-to-thrive, progressive ataxia, and a transition from generalized absence to tonic-clonic to ultimately fatal convulsive status epilepticus. Binding and electrophysiological studies demonstrate use-dependent downregulation of GABA(A) and (B) receptors in the mutant mouse. Translational human studies similarly reveal downregulation of GABAergic activity in patients, utilizing flumazenil-PET and transcranial magnetic stimulation for GABA(A) and (B) activity, respectively. Sleep studies reveal decreased stage REM with prolonged REM latencies and diminished percentage of stage REM. An ad libitum ketogenic diet was reported as effective in the mouse model, with unclear applicability to the human condition. Acute application of SGS-742, a GABA(B) antagonist, leads to improvement in epileptiform activity on electrocorticography. Promising mouse data using compounds available for clinical use, including taurine and SGS-742, form the framework for human trials.

  8. Thermal and thermomechanical properties of poly(butylene succinate) nanocomposites.

    PubMed

    Makhatha, Mamookho E; Ray, Suprakas Sinha; Hato, Joseph; Luyt, Adriaan S

    2008-04-01

    This article describes the thermal and thermomechanical properties of poly(butylene succinate) (PBS) and its nanocomposites. PBS nanocomposites with three different weight ratios of organically modified synthetic fluorine mica (OMSFM) have been prepared by melt-mixing in a batch mixer at 140 degrees C. The structure and morphology of the nanocomposites were characterized by X-ray diffraction (XRD) analyses and transmission electron microscopy (TEM) observations that reveal the homogeneous dispersion of the intercalated silicate layers into the PBS matrix. The thermal properties of pure PBS and the nanocomposite samples were studied by both conventional and temperature modulated differential scanning calorimetry (DSC) analyses, which show multiple melting behavior of the PBS matrix. The investigation of the thermomechanical properties was performed by dynamic mechanical analysis. Results reveal significant improvement in the storage modulus of neat PBS upon addition of OMSFM. The tensile modulus of neat PBS is also increased substantially with the addition of OMSFM, however, the strength at yield and elongation at break of neat PBS systematically decreases with the loading of OMSFM. The thermal stability of the nanocomposites compared to that of the pure polymer sample was examined under both pyrolytic and thermo-oxidative environments. It is shown that the thermal stability of PBS is increased moderately in the presence of 3 wt% of OMSFM, but there is no significant effect on further silicate loading in the oxidative environment. In the nitrogen environment, however, the thermal stability systematically decreases with increasing clay loading.

  9. Batch- and continuous propionic acid production from glycerol using free and immobilized cells of Propionibacterium acidipropionici.

    PubMed

    Dishisha, Tarek; Alvarez, Maria Teresa; Hatti-Kaul, Rajni

    2012-08-01

    Propionic acid production from glycerol was studied using Propionibacterium acidipropionici DSM 4900 cells immobilized on polyethylenimine-treated Poraver (PEI-Poraver) and Luffa (PEI-Luffa), respectively. Using PEI-Luffa, the average productivity, yield and concentration of propionic acid from 40 g L(-1) glycerol were 0.29 g L(-1) h(-1), 0.74 mol(PA) mol(Gly)(-1) and 20 g L(-1), respectively, after four consecutive recycle-batches. PEI-Poraver supported attachment of 31 times higher amounts of cells than PEI-Luffa and produced 20, 28 and 35 g L(-1) propionic acid from 40, 65 and 85 g L(-1) glycerol, respectively (0.61 mol(PA) mol(Gly)(-1)). The corresponding production rates were 0.86, 0.43 and 0.35 g L(-1) h(-1), which are the highest reported from glycerol via batch or fed-batch fermentations for equivalent propionic acid concentrations. Using a continuous mode of operation at a dilution rate of 0.1 h(-1), cell washout was observed in the bioreactor with free cells; however, propionic acid productivity, yield and concentration were 1.40 g L(-1) h(-1), 0.86 mol(PA) mol(Gly)(-1), and 15 g L(-1), respectively, using immobilized cells in the PEI-Poraver bioreactor. The choice of the immobilization matrix can thus significantly influence the fermentation efficiency and profile. The bioreactor using cells immobilized on PEI-Poraver allowed the fermentation of higher glycerol concentrations and provided stable and higher fermentation rates than that using free cells or the cells immobilized on PEI-Luffa.

  10. Topical monotherapy with clobetasol propionate spray 0.05% in the COBRA trial.

    PubMed

    Menter, Alan

    2007-11-01

    The Clobex Spray Community-Based Research Assessment (COBRA) trial, a large, 4-week, open-label, observational trial, evaluated the use of twice-daily clobetasol propionate spray 0.05% in subjects with moderate to severe plaque psoriasis affecting 3% to 20% body surface area (BSA). The study was designed to augment existing phase 3 clinical trial data. In this trial, 1254 subjects in the effectiveness-evaluable (EE) population were treated with clobetasol propionate spray 0.05% as monotherapy. Clinical effectiveness was evaluated at weeks 2 and 4 using a 6-point target plaque severity (TPS) scale and 7-point investigators' global assessment of improvement (GAI) scale. Psoriasis TPS at week 0 (baseline) was rated as moderate to severe in more than 90% of subjects. After 2 weeks of clobetasol propionate spray 0.05% monotherapy, statistically significant improvement in TPS was seen at weeks 2 and 4 (P < .001). In addition, statistically significant improvement was seen at week 4 versus week 2 (P < .001) using the GAI scale. Clobetasol propionate spray 0.05% monotherapy was well-tolerated as assessed by erythema, peeling/scaling, dryness, stinging/burning, telangiectasia, skin atrophy, pruritus, and folliculitis. Skin and subcutaneous tissue disorders as well as general disorders and application-site conditions defined as possibly or probably related to therapy occurred in 1.0% and less than 1.0% of subjects, respectively. In addition, more than 90% of subjects were reported by investigators as being very satisfied or somewhat satisfied with their treatment at week 4. Based on these data, clobetasol propionate spray 0.05% is an effective and convenient topical monotherapy for moderate to severe plaque psoriasis.

  11. Glycerol/glucose co-fermentation: one more proficient process to produce propionic acid by Propionibacterium acidipropionici.

    PubMed

    Liu, Yin; Zhang, Yong-Guang; Zhang, Ru-Bing; Zhang, Fan; Zhu, Jianhang

    2011-01-01

    Cosubstrates fermentation is such an effective strategy for increasing subject metabolic products that it could be available and studied in propionic acid production, using glycerol and glucose as carbon resources. The effects of glycerol, glucose, and their mixtures on the propionic acid production by Propionibacterium acidipropionici CGMCC1.2225 (ATCC4965) were studied, with the aim of improving the efficiency of propionic acid production. The propionic acid yield from substrate was improved from 0.475 and 0.303 g g(-1) with glycerol and glucose alone, respectively, to 0.572 g g(-1) with co-fermentation of a glycerol/glucose mixture of 4/1 (mol/mol). The maximal propionic acid and substrate conversion rate were 21.9 g l(-1) and 57.2% (w/w), respectively, both significantly higher than for a sole carbon source. Under optimized conditions of fed-batch fermentation, the maximal propionic acid yield and substrate conversion efficiency were 29.2 g l(-1) and 54.4% (w/w), respectively. These results showed that glycerol/glucose co-fermentation could serve as an excellent alternative to conventional propionic acid fermentation.

  12. Cloning, expression, purification, crystallization and preliminary X-ray diffraction analysis of propionate kinase (TdcD) from Salmonella typhimurium

    SciTech Connect

    Simanshu, Dhirendra K.; Murthy, M. R. N.

    2005-01-01

    Propionate kinase (TdcD) from S. typhimurium has been expressed, purified and crystallized. A diffraction data set has been collected to 2.2 Å resolution. In the cell, propionate is mainly formed during β-oxidation of odd-numbered carbon-chain fatty acids, fermentation of carbohydrates and degradation of the amino acids threonine, valine, isoleucine and methionine. Recently, it has been shown that l-threonine is non-oxidatively cleaved to propionate via 2-ketobutyrate. The last step in this process, conversion of propionyl phosphate and ADP to propionate and ATP, is catalysed by propionate kinase (EC 2.7.1.–). Here, the cloning of propionate kinase (molecular weight 44 kDa) from Salmonella typhimurium with an N-terminal hexahistidine affinity tag and its overexpression in Escherichia coli are reported. Purified propionate kinase was found to cocrystallize with ADP in the hanging-drop vapour-diffusion and microbatch methods. Crystals belong to space group P3{sub 1}21 or P3{sub 2}21, with unit-cell parameters a = b = 111.47, c = 66.52 Å. A complete data set to 2.2 Å resolution has been collected using an image-plate detector system mounted on a rotating-anode X-ray generator.

  13. Acetate fuels the cancer engine.

    PubMed

    Lyssiotis, Costas A; Cantley, Lewis C

    2014-12-18

    Cancer cells have distinctive nutrient demands to fuel growth and proliferation, including the disproportionate use of glucose, glutamine, and fatty acids. Comerford et al. and Mashimo et al. now demonstrate that several types of cancer are avid consumers of acetate, which facilitates macromolecular biosynthesis and histone modification.

  14. Conversion of succinic acid to 1,4-butanediol via dimethyl succinate over rhenium nano-catalyst supported on copper-containing mesoporous carbon.

    PubMed

    Hong, Ung Gi; Kim, Jeong Kwon; Lee, Joongwon; Lee, Jong Kwon; Yi, Jongheop; Song, In Kyu

    2014-11-01

    Copper-containing mesoporous carbons (XCu-MC) with different copper content (X = 8.0, 12.7, 15.9, 23.3, and 26.8 wt%) were prepared by a single-step surfactant-templating method. Rhenium nano-catalysts supported on copper-containing mesoporous carbons (Re/XCu-MC) were then prepared by an incipient wetness method. Re/XCu-MC (X = 8.0, 12.7, 15.9, 23.3, and 26.8 wt%) catalysts were characterized by nitrogen adsorption-desorption isotherm, HR-TEM, FT-IR, and H2- TPR analyses. Liquid-phase hydrogenation of succinic acid to 1,4-butanediol (BDO) via dimethyl succinate (DMS) was carried out over Re/XCu-MC catalysts in a batch reactor. The effect of copper content on the physicochemical properties and catalytic activities of Re/XCu-MC catalysts in the hydrogenation of succinic acid to BDO was investigated. Re/XCu-MC catalysts retained different physicochemical properties depending on copper content. In the hydrogenation of succinic acid to BDO, yield for BDO showed a volcano-shaped trend with respect to copper content. Thus, an optimal copper content was required to achieve maximum catalytic performance of Re/XCu-MC. It was also observed that yield for BDO increased with increasing the amount of hydrogen consumption by copper in the Re/XCu-MC catalysts.

  15. Propionate Ameliorates Dextran Sodium Sulfate-Induced Colitis by Improving Intestinal Barrier Function and Reducing Inflammation and Oxidative Stress

    PubMed Central

    Tong, Ling-chang; Wang, Yue; Wang, Zhi-bin; Liu, Wei-ye; Sun, Sheng; Li, Ling; Su, Ding-feng; Zhang, Li-chao

    2016-01-01

    Propionate is a short chain fatty acid that is abundant as butyrate in the gut and blood. However, propionate has not been studied as extensively as butyrate in the treatment of colitis. The present study was to investigate the effects of sodium propionate on intestinal barrier function, inflammation and oxidative stress in dextran sulfate sodium (DSS)-induced colitis mice. Animals in DSS group received drinking water from 1 to 6 days and DSS [3% (w/v) dissolved in double distilled water] instead of drinking water from 7 to 14 days. Animals in DSS+propionate (DSS+Prop) group were given 1% sodium propionate for 14 consecutive days and supplemented with 3% DSS solution on day 7–14. Intestinal barrier function, proinflammatory factors, oxidative stress, and signal transducer and activator of transcription 3 (STAT3) signaling pathway in the colon were determined. It was found that sodium propionate ameliorated body weight loss, colon-length shortening and colonic damage in colitis mice. Sodium propionate significantly inhibited the increase of FITC-dextran in serum and the decrease of zonula occludens-1 (ZO-1), occludin, and E-cadherin expression in the colonic tissue. It also inhibited the expression of interleukin (IL)-1β, IL-6, and tumor necrosis factor-α (TNF-α) mRNA and phosphorylation of STAT3 in colitis mice markedly, reduced the myeloperoxidase (MPO) level, and increased the superoxide dismutase and catalase level in colon and serum compared with DSS group. Sodium propionate inhibited macrophages with CD68 marker infiltration into the colonic mucosa of colitis mice. These results suggest that oral administration of sodium propionate could ameliorate DSS-induced colitis mainly by improving intestinal barrier function and reducing inflammation and oxidative stress via the STAT3 signaling pathway. PMID:27574508

  16. Origins of blood acetate in the rat.

    PubMed Central

    Buckley, B M; Williamson, D H

    1977-01-01

    A novel enzymimc cycling assay for the determination of acetate in biological material is described. Measurements of the acetate concentration in blood and liver samples from rats of various ages and nutritional states with this assay are reported. The contribution of the intestine, the liver and the rest of the body to maintaining the concentration of acetate in the circulation is examined. Evidence is presented that the gut flora constitute the main source of acetate in blood of fed adult rats, though endogenous production of acetate is of significance in other situations. The streptozotocin-diabetic rat has an elevated blood acetate concentration. PMID:597244

  17. Bio-oil based biorefinery strategy for the production of succinic acid

    PubMed Central

    2013-01-01

    Background Succinic acid is one of the key platform chemicals which can be produced via biotechnology process instead of petrochemical process. Biomass derived bio-oil have been investigated intensively as an alternative of diesel and gasoline fuels. Bio-oil could be fractionized into organic phase and aqueous phase parts. The organic phase bio-oil can be easily upgraded to transport fuel. The aqueous phase bio-oil (AP-bio-oil) is of low value. There is no report for its usage or upgrading via biological methods. In this paper, the use of AP-bio-oil for the production of succinic acid was investigated. Results The transgenic E. coli strain could grow in modified M9 medium containing 20 v/v% AP-bio-oil with an increase in OD from 0.25 to 1.09. And 0.38 g/L succinic acid was produced. With the presence of 4 g/L glucose in the medium, succinic acid concentration increased from 1.4 to 2.4 g/L by addition of 20 v/v% AP-bio-oil. When enzymatic hydrolysate of corn stover was used as carbon source, 10.3 g/L succinic acid was produced. The obtained succinic acid concentration increased to 11.5 g/L when 12.5 v/v% AP-bio-oil was added. However, it decreased to 8 g/L when 50 v/v% AP-bio-oil was added. GC-MS analysis revealed that some low molecular carbon compounds in the AP-bio-oil were utilized by E. coli. Conclusions The results indicate that AP-bio-oil can be used by E. coli for cell growth and succinic acid production. PMID:23657107

  18. 3-Nitropropionate, the toxic substance of Indigofera, is a suicide inactivator of succinate dehydrogenase.

    PubMed

    Alston, T A; Mela, L; Bright, H J

    1977-09-01

    We have shown that 3-nitropropionate, an isoelectronic analogue of succinate, is a suicide inactivator of succinate dehydrogenase [succinate:(acceptor) oxidoreductase, EC 1.3.99.1] as follows. (i) When rat liver mitochondria oxidize succinate in the presence of 3-nitropropionate carbanion, the rate of O(2) consumption decreases exponentially to a zero value. This pattern is duplicated by subsequent additions of mitochondria. The dependence of the apparent first-order rate constant for enzyme inhibition, as well as the number of enzyme turnovers completed before inhibition, on the concentrations of 3-nitropropionate carbanion and succinate are those expected for an active site-directed and irreversible inhibitor. (ii) The inactivated enzyme is not resuscitated by centrifugation and washing of the mitochondria, in contrast to malonate-treated enzyme, and malonate protects against irreversible, inhibition. (iii) The inhibitor species is 3-nitropropionate carbanion and no external nucleophile is required for inhibition. (iv) The respiratory rates, respiratory control ratios, and ADP/O ratios obtained with NAD-linked substrates are unaffected by 3-nitropropionate carbanion. These results show that 3-nitropropionate carbanion is a highly specific, time-dependent, and irreversible inhibitor of succinate dehydrogenase. By analogy with the reaction of nitroethane with D-amino acid oxidase, the data are consistent with the hypothesis that the carbanionic inhibitor forms a covalent N-5 adduct with the active site flavin. However, the precise mechanism of inactivation, as well as mechanistic extrapolations to the oxidation of succinate, must await the elucidation of the structure of the modified enzyme. We can now explain the toxicity of plants such as Indigofera endecaphylla for mammals and fowl as being due to the irreversible blockage of the Krebs cycle by 3-nitropropionate carbanion.

  19. 3-Nitropropionate, the toxic substance of Indigofera, is a suicide inactivator of succinate dehydrogenase

    PubMed Central

    Alston, Theodore A.; Mela, Leena; Bright, Harold J.

    1977-01-01

    We have shown that 3-nitropropionate, an isoelectronic analogue of succinate, is a suicide inactivator of succinate dehydrogenase [succinate:(acceptor) oxidoreductase, EC 1.3.99.1] as follows. (i) When rat liver mitochondria oxidize succinate in the presence of 3-nitropropionate carbanion, the rate of O2 consumption decreases exponentially to a zero value. This pattern is duplicated by subsequent additions of mitochondria. The dependence of the apparent first-order rate constant for enzyme inhibition, as well as the number of enzyme turnovers completed before inhibition, on the concentrations of 3-nitropropionate carbanion and succinate are those expected for an active site-directed and irreversible inhibitor. (ii) The inactivated enzyme is not resuscitated by centrifugation and washing of the mitochondria, in contrast to malonate-treated enzyme, and malonate protects against irreversible, inhibition. (iii) The inhibitor species is 3-nitropropionate carbanion and no external nucleophile is required for inhibition. (iv) The respiratory rates, respiratory control ratios, and ADP/O ratios obtained with NAD-linked substrates are unaffected by 3-nitropropionate carbanion. These results show that 3-nitropropionate carbanion is a highly specific, time-dependent, and irreversible inhibitor of succinate dehydrogenase. By analogy with the reaction of nitroethane with D-amino acid oxidase, the data are consistent with the hypothesis that the carbanionic inhibitor forms a covalent N-5 adduct with the active site flavin. However, the precise mechanism of inactivation, as well as mechanistic extrapolations to the oxidation of succinate, must await the elucidation of the structure of the modified enzyme. We can now explain the toxicity of plants such as Indigofera endecaphylla for mammals and fowl as being due to the irreversible blockage of the Krebs cycle by 3-nitropropionate carbanion. PMID:269430

  20. Anaerobic glyoxylate cycle activity during simultaneous utilization of glycogen and acetate in uncultured Accumulibacter enriched in enhanced biological phosphorus removal communities.

    PubMed

    Burow, Luke C; Mabbett, Amanda N; Blackall, Linda L

    2008-10-01

    Enhanced biological phosphorus removal (EBPR) communities protect waterways from nutrient pollution and enrich microorganisms capable of assimilating acetate as polyhydroxyalkanoate (PHA) under anaerobic conditions. Accumulibacter, an important uncultured polyphosphate-accumulating organism (PAO) enriched in EBPR, was investigated to determine the central metabolic pathways responsible for producing PHA. Acetate uptake and assimilation to PHA in Accumulibacter was confirmed using fluorescence in situ hybridization (FISH)-microautoradiography and post-FISH chemical staining. Assays performed with enrichments of Accumulibacter using an inhibitor of glyceraldehyde-3-phosphate dehydrogenase inferred anaerobic glycolysis activity. Significant decrease in anaerobic acetate uptake and PHA production rates were observed using inhibitors targeting enzymes within the glyoxylate cycle. Bioinformatic analysis confirmed the presence of genes unique to the glyoxylate cycle (isocitrate lyase and malate synthase) and gene expression analysis of isocitrate lyase demonstrated that the glyoxylate cycle is likely involved in PHA production. Reduced anaerobic acetate uptake and PHA production was observed after inhibition of succinate dehydrogenase and upregulation of a succinate dehydrogenase gene suggested anaerobic activity. Cytochrome b/b(6) activity inferred that succinate dehydrogenase activity in the absence of external electron acceptors may be facilitated by a novel cytochrome b/b(6) fusion protein complex that pushes electrons uphill to more electronegative electron carriers. Identification of phosphoenolpyruvate carboxylase and phosphoenolpyruvate carboxykinase genes in Accumulibacter demonstrated the potential for interconversion of C(3) intermediates of glycolysis and C(4) intermediates of the glyoxylate cycle. Our findings along with previous hypotheses from analysis of microbiome data and metabolic models for PAOs were used to develop a model for anaerobic carbon

  1. The expression of succinate dehydrogenase in breast phyllodes tumor.

    PubMed

    Choi, Junjeong; Kim, Do Hee; Jung, WooHee; Koo, Ja Seung

    2014-10-01

    The purpose of this study is to investigate the expression of succinate dehydrogenase (SDH)A, SDHB, and HIF-1α in phyllodes tumors and the association with clinic-pathologic factors. Using tissue microarray (TMA) for 206 phyllodes tumor cases, we performed immunohistochemical stains for SDHA, SDHB, and HIF-1α and analyzed their expression in regard to clinicopathologic parameters of each case. The cases were comprised of 156 benign, 34 borderline, and 16 malignant phyllodes tumors. The expression of stromal SDHA and epithelial- and stromal- SDHB increased as the tumor progressed from benign to malignant (P⟨0.001). There were five stromal SDHA-negative cases and 31 stromal SDHB-negative cases. SDHB negativity was associated with a lower histologic grade (P=0.054) and lower stromal atypia (P=0.048). Univariate analysis revealed that a shorter disease free survival (DFS) was associated with stromal SDHB high-positivity (P=0.013) and a shorter overall survival (OS) was associated with high-positivity of stromal SDHA and SDHB (P⟨0.001 and P⟨0.001, respectively). The multivariate Cox analysis with the variables stromal cellularity, stromal atypia, stromal mitosis, stromal overgrowth, tumor margin, stromal SDHA expression, and stromal SDHB expression revealed that stromal overgrowth was associated with a shorter DFS (hazard ratio: 24.78, 95% CI: 3.126-196.5, P=0.002) and a shorter OS (hazard ratio: 176.7, 95% CI: 8.466-3691, P=0.001). In conclusion, Tumor grade is positively correlated with SDHA and SDHB expression in the tumor stroma in phyllodes tumors of the breast. This result may be attributed to the increased metabolic demand in high grade tumors.

  2. A ketogenic diet increases succinic dehydrogenase activity in aging cardiomyocytes.

    PubMed

    Balietti, Marta; Fattoretti, Patrizia; Giorgetti, Belinda; Casoli, Tiziana; Di Stefano, Giuseppina; Solazzi, Moreno; Platano, Daniela; Aicardi, Giorgio; Bertoni-Freddari, Carlo

    2009-08-01

    Impairment of energy metabolism and an increase of reactive oxygen species (ROS) production seem to play a major role in age-related apoptotic loss of cardiomyocytes. Succinic dehydrogenase (SDH) is an important marker of the mitochondrial capability to provide an adequate amount of ATP. Moreover, because of its unique redox properties, SDH activity contributes to maintain the reduced state of the ubiquinone pool. Recent reports have shown that ketone body intake improves cardiac metabolic efficiency and exerts a cardioprotective antioxidant action, we therefore performed a cytochemical investigation of SDH activity in cardiomyocytes of late-adult (19-month-old) rats fed for 8 weeks with a medium-chain triglycerides ketogenic diet (MCT-KD). Young, age-matched and old animals fed with a standard chow were used as controls. The overall area of the precipitates (PA) from SDH activity and the area of the SDH-positive mitochondria (MA) were measured. The percent ratios PA/MA and MA/total myocardial tissue area (MA/TA) were the parameters taken into account. We found that PA/MA was significantly higher in young control rats and in MCT-KD-fed rats versus late-adult and old control rats and in young control versus MCT-KD-fed rats. MA/TA of MCT-KD-fed rats was significantly higher versus age-matched and old control rats and tended to be higher versus young control rats; this parameter was significantly higher in young versus old control rats. Thus, MCT-KD intake partially recovers age-related decrease of SDH activity and increases the myocardial area occupied by metabolically active mitochondria. These effects might counteract metabolic alterations leading to apoptosis-induced myocardial atrophy and failure during aging.

  3. Acetic Acid, the Active Component of Vinegar, Is an Effective Tuberculocidal Disinfectant

    PubMed Central

    Cortesia, Claudia; Vilchèze, Catherine; Bernut, Audrey; Contreras, Whendy; Gómez, Keyla; de Waard, Jacobus; Jacobs, William R.; Kremer, Laurent; Takiff, Howard

    2014-01-01

    ABSTRACT Effective and economical mycobactericidal disinfectants are needed to kill both Mycobacterium tuberculosis and non-M. tuberculosis mycobacteria. We found that acetic acid (vinegar) efficiently kills M. tuberculosis after 30 min of exposure to a 6% acetic acid solution. The activity is not due to pH alone, and propionic acid also appears to be bactericidal. M. bolletii and M. massiliense nontuberculous mycobacteria were more resistant, although a 30-min exposure to 10% acetic acid resulted in at least a 6-log10 reduction of viable bacteria. Acetic acid (vinegar) is an effective mycobactericidal disinfectant that should also be active against most other bacteria. These findings are consistent with and extend the results of studies performed in the early and mid-20th century on the disinfectant capacity of organic acids. IMPORTANCE  Mycobacteria are best known for causing tuberculosis and leprosy, but infections with nontuberculous mycobacteria are an increasing problem after surgical or cosmetic procedures or in the lungs of cystic fibrosis and immunosuppressed patients. Killing mycobacteria is important because Mycobacterium tuberculosis strains can be multidrug resistant and therefore potentially fatal biohazards, and environmental mycobacteria must be thoroughly eliminated from surgical implements and respiratory equipment. Currently used mycobactericidal disinfectants can be toxic, unstable, and expensive. We fortuitously found that acetic acid kills mycobacteria and then showed that it is an effective mycobactericidal agent, even against the very resistant, clinically important Mycobacterium abscessus complex. Vinegar has been used for thousands of years as a common disinfectant, and if it can kill mycobacteria, the most disinfectant-resistant bacteria, it may prove to be a broadly effective, economical biocide with potential usefulness in health care settings and laboratories, especially in resource-poor countries. PMID:24570366

  4. Acetic Acid, the active component of vinegar, is an effective tuberculocidal disinfectant.

    PubMed

    Cortesia, Claudia; Vilchèze, Catherine; Bernut, Audrey; Contreras, Whendy; Gómez, Keyla; de Waard, Jacobus; Jacobs, William R; Kremer, Laurent; Takiff, Howard

    2014-02-25

    Effective and economical mycobactericidal disinfectants are needed to kill both Mycobacterium tuberculosis and non-M. tuberculosis mycobacteria. We found that acetic acid (vinegar) efficiently kills M. tuberculosis after 30 min of exposure to a 6% acetic acid solution. The activity is not due to pH alone, and propionic acid also appears to be bactericidal. M. bolletii and M. massiliense nontuberculous mycobacteria were more resistant, although a 30-min exposure to 10% acetic acid resulted in at least a 6-log10 reduction of viable bacteria. Acetic acid (vinegar) is an effective mycobactericidal disinfectant that should also be active against most other bacteria. These findings are consistent with and extend the results of studies performed in the early and mid-20th century on the disinfectant capacity of organic acids. IMPORTANCE Mycobacteria are best known for causing tuberculosis and leprosy, but infections with nontuberculous mycobacteria are an increasing problem after surgical or cosmetic procedures or in the lungs of cystic fibrosis and immunosuppressed patients. Killing mycobacteria is important because Mycobacterium tuberculosis strains can be multidrug resistant and therefore potentially fatal biohazards, and environmental mycobacteria must be thoroughly eliminated from surgical implements and respiratory equipment. Currently used mycobactericidal disinfectants can be toxic, unstable, and expensive. We fortuitously found that acetic acid kills mycobacteria and then showed that it is an effective mycobactericidal agent, even against the very resistant, clinically important Mycobacterium abscessus complex. Vinegar has been used for thousands of years as a common disinfectant, and if it can kill mycobacteria, the most disinfectant-resistant bacteria, it may prove to be a broadly effective, economical biocide with potential usefulness in health care settings and laboratories, especially in resource-poor countries.

  5. The impact of postnatal leuprolide acetate treatment on reproductive characteristics in a rodent model of polycystic ovary syndrome.

    PubMed

    Serrano Mujica, Lady Katerine; Bertolin, Kalyne; Bridi, Alessandra; Glanzner, Werner Giehl; Rissi, Vitor Braga; de Camargo, Flávia de Los Santos; Zanella, Renato; Prestes, Osmar Damian; Moresco, Rafael Noal; Antoniazzi, Alfredo Quites; Dias Gonçalves, Paulo Bayard; Premaor, Melissa Orlandin; Comim, Fabio Vasconcellos

    2017-02-15

    In this study, a GnRH agonist, leuprolide acetate (LA), was given as a single depot injection before 48 h of life to Wistar female rats allotted to prenatal (E16-18) and postnatal androgenization (day 5 of life) by the use of testosterone propionate, looking for reproductive endpoints. Remarkably, a single injection of LA increased the estrus cycles in the postnatal group (PostN) from 0% to 25% of the estrus cycles in the postnatal LA treated group (PostN L). LA also reduced the serum testosterone levels and cysts and atretic follicles in PostN L in contrast with rats (>100 days) from the PostN group (p = 0.04). Prenatally androgenized rats (PreN) exhibited significant modifications in the hypothalamic genes, such as Gnrh. To the best of our knowledge, this is the first study to show that blockage of the GnRH axis with leuprolide acetate depot prevented the development of typical features (anovulation, cysts, atretic follicles) in a postnatal testosterone propionate rat model of PCOS.

  6. Carbon-isotopic analysis of dissolved acetate

    NASA Technical Reports Server (NTRS)

    Gelwicks, J. T.; Hayes, J. M.

    1990-01-01

    Heating of dried, acetate-containing solids together with oxalic acid dihydrate conveniently releases acetic acid for purification by gas chromatography. For determination of the carbon-isotopic composition of total acetate, the acetate-containing zone of the chromatographic effluent can be routed directly to a combustion furnace coupled to a vacuum system allowing recovery, purification, and packaging of CO2 for mass-spectrometric analysis. For analysis of methyl carbon, acetic acid can be cryogenically trapped from the chromatographic effluent, then transferred to a tube containing excess NaOH. The tube is evacuated, sealed, and heated to 500 degrees C to produce methane by pyrolysis of sodium acetate. Subsequent combustion of the methane allows determination of the 13C content at the methyl position in the parent acetate. With typical blanks, the standard deviation of single analyses is less than 0.4% for acetate samples larger than 5 micromoles. A full treatment of uncertainties is outlined.

  7. Ozone decomposition in aqueous acetate solutions

    SciTech Connect

    Sehested, K.; Holcman, J.; Bjergbakke, E.; Hart, E.J.

    1987-01-01

    The acetate radical ion reacts with ozone with a rate constant of k = (1.5 +/- 0.5) x 10Z dmT mol s . The products from this reaction are CO2, HCHO, and O2 . By subsequent reaction of the peroxy radical with ozone the acetate radical ion is regenerated through the OH radical. A chain decomposition of ozone takes place. It terminates when the acetate radical ion reacts with oxygen forming the unreactive peroxy acetate radical. The chain is rather short as oxygen is developed, as a result of the ozone consumption. The inhibiting effect of acetate on the ozone decay is rationalized by OH scavenging by acetate and successive reaction of the acetate radical ion with oxygen. Some products from the bimolecular disappearance of the peroxy acetate radicals, however, react further with ozone, reducing the effectiveness of the stabilization.

  8. Carbon-isotopic analysis of dissolved acetate.

    PubMed

    Gelwicks, J T; Hayes, J M

    1990-01-01

    Heating of dried, acetate-containing solids together with oxalic acid dihydrate conveniently releases acetic acid for purification by gas chromatography. For determination of the carbon-isotopic composition of total acetate, the acetate-containing zone of the chromatographic effluent can be routed directly to a combustion furnace coupled to a vacuum system allowing recovery, purification, and packaging of CO2 for mass-spectrometric analysis. For analysis of methyl carbon, acetic acid can be cryogenically trapped from the chromatographic effluent, then transferred to a tube containing excess NaOH. The tube is evacuated, sealed, and heated to 500 degrees C to produce methane by pyrolysis of sodium acetate. Subsequent combustion of the methane allows determination of the 13C content at the methyl position in the parent acetate. With typical blanks, the standard deviation of single analyses is less than 0.4% for acetate samples larger than 5 micromoles. A full treatment of uncertainties is outlined.

  9. A novel whole-phase succinate fermentation strategy with high volumetric productivity in engineered Escherichia coli.

    PubMed

    Li, Yikui; Li, Mingji; Zhang, Xu; Yang, Peng; Liang, Quanfeng; Qi, Qingsheng

    2013-12-01

    The strategic design of this study aims at fermentative succinate production with high volumetric productivity in engineered Escherichia coli. An E. coli YL106/pSCsfcA was engineered to produce succinate under aerobic, microaerobic and anaerobic conditions by derepressing the inhibition of low dissolved oxygen, eliminating the NADH competitive pathways, modulating the redistribution of metabolic flux, and increasing the transport rate of the sole carbon source glucose. Based on this strain, a novel "whole-phase" succinate production strategy was further developed, in which the engineered strain was first cultivated aerobically, then shifted to microaerobic phase at the end of exponential growth, and finally kept in anaerobic phase until the end of fermentation. Employing this strategy, the engineered E. coli YL106/pSCsfcA was able to produce 85.30 g l(-1) succinate with an overall volumetric productivity of 2.13 g l(-1)h(-1). This process offers an efficiently fermentative method for industrial succinate production in metabolically engineered E. coli.

  10. Tablet splitting: Product quality assessment of metoprolol succinate extended release tablets.

    PubMed

    Zhao, Na; Zidan, Ahmed; Tawakkul, Mobin; Sayeed, Vilayat A; Khan, Mansoor

    2010-11-30

    Metoprolol succinate extended release tablets comprise a multiple unit system containing metoprolol succinate in a multitude of controlled release pellets. Each pellet acts as a separate drug delivery unit and is designed to deliver metoprolol continuously over the dosage interval. Despite the flexibility that controlled release pellets may offer, segregation is one of the challenges that commonly occur during tableting for such drug delivery system. Since all commercial metoprolol succinate extended release tablets are scored, they are deemed suitable for splitting. The present study was aimed at utilizing an innovative technology to determine the dose uniformity for split tablets. Four marketed drug products consisting of innovator and generics were evaluated for effect of splitting on weight, assay and content uniformity. Novel analytical tool such as near infrared (NIR) chemical imaging was used to visualize the distribution of metoprolol succinate and functional excipients on the surfaces of the marketed tablets. The non-homogeneous distribution of directly compressed metoprolol succinate beads on the surface of the tablets as well as the split intersection explained the large variation in the split tablets' weight and content uniformity results. The obtained results indicated the usefulness of NIR chemical imaging to determine the need for content uniformity studies for certain split tablets.

  11. Succinate is a preferential metabolic stimulus-coupling signal for glucose-induced proinsulin biosynthesis translation.

    PubMed

    Alarcon, Cristina; Wicksteed, Barton; Prentki, Marc; Corkey, Barbara E; Rhodes, Christopher J

    2002-08-01

    The secondary signals emanating from increased glucose metabolism, which lead to specific increases in proinsulin biosynthesis translation, remain elusive. It is known that signals for glucose-stimulated insulin secretion and proinsulin biosynthesis diverge downstream of glycolysis. Consequently, the mitochondrial products ATP, Krebs cycle intermediates, glutamate, and acetoacetate were investigated as candidate stimulus-coupling signals specific for glucose-induced proinsulin biosynthesis in rat islets. Decreasing ATP levels by oxidative phosphorylation inhibitors showed comparable effects on proinsulin biosynthesis and total protein synthesis. Although it is a cofactor, ATP is unlikely to be a metabolic stimulus-coupling signal specific for glucose-induced proinsulin biosynthesis. Neither glutamic acid methyl ester nor acetoacetic acid methyl ester showed a specific effect on glucose-stimulated proinsulin biosynthesis. Interestingly, among Krebs cycle intermediates, only succinic acid monomethyl ester specifically stimulated proinsulin biosynthesis. Malonic acid methyl ester, an inhibitor of succinate dehydrogenase, also specifically increased glucose-induced proinsulin biosynthesis without affecting islet ATP levels or insulin secretion. Glucose caused a 40% increase in islet intracellular succinate levels, but malonic acid methyl ester showed no further effect, probably due to efficient conversion of succinate to succinyl-CoA. In this regard, a GTP-dependent succinyl-CoA synthetase activity was found in cytosolic fractions of pancreatic islets. Thus, succinate and/or succinyl-CoA appear to be preferential metabolic stimulus-coupling factors for glucose-induced proinsulin biosynthesis translation.

  12. Characterization of succinate dehydrogenase and alpha-glycerophosphate dehydrogenase in pancreatic islets.

    PubMed

    Lenzen, S; Panten, U

    1983-12-01

    Succinate dehydrogenase activities in homogenates of rat and ob/ob mouse pancreatic islets were only 13% of the activities in homogenates of liver and were also several times lower than in homogenates of pancreatic acinar tissue. This indicates that the content of mitochondria in pancreatic islet cells is very low. The very low activity of succinate dehydrogenase is in agreement with the low mitochondrial volume in the cytoplasmic ground substance of pancreatic islet cells as observed in morphometric studies. This may represent the poor equipment of pancreatic islet cells with electron transport chains and thus provide a regulatory role for the generation of reducing equivalents and chemical energy for the regulation of insulin secretion. The activities of succinate dehydrogenase in tissue homogenates of pancreatic islets, pancreatic acinar tissue, and liver were significantly inhibited by malonate and diazoxide but not by glucose, mannoheptulose, streptozotocin, or verapamil. Tolbutamide inhibited only pancreatic islet succinate dehydrogenase significantly, providing evidence for a different behavior of pancreatic islet cell mitochondria. Therefore diazoxide and tolbutamide may affect pancreatic islet function through their effects on succinate dehydrogenase activity. The activities of alpha-glycerophosphate dehydrogenase in homogenates of pancreatic islets and liver from rats and ob/ob mice were in the same range, while activities in homogenates of pancreatic acinar tissue were lower. None of the test agents affected alpha-glycerophosphate dehydrogenase activity. Thus the results provide no support for the recent contention that alpha-glycerophosphate dehydrogenase activity may be critical for the regulation of insulin secretion.

  13. Lyotropic liquid crystal behaviour of azelate and succinate monoester surfactants based on fragrance alcohols.

    PubMed

    Marchal, Frédéric; Nardello-Rataj, Véronique; Chailloux, Nelly; Aubry, Jean-Marie; Tiddy, Gordon J T

    2008-05-01

    Azelaic acid was used as a starting material for the preparation of new monoester surfactants based on fragrance alcohols. Sodium monocitronellyl azelate (citroC(9)Na) and sodium monomenthyl azelate (menC(9)Na) were synthesized and their aqueous phase behaviour was studied. For comparison, monoesters derived from succinic anhydride, i.e. sodium monocitronellyl succinate (citroC(4)Na) and sodium monomenthyl succinate (menC(4)Na), were also prepared as well as sodium monodecyl succinate (C(10)C(4)Na) and sodium monodecyl azelate (C(10)C(9)Na) in order to study the effect of the position of the ester function inside the hydrophobic tail and of branching and unsaturation respectively. Liquid crystal structures were examined by optical polarising microscopy and schematic partial binary phase diagrams (surfactant+water, 0-100 wt%, 10-90 degrees C) of the surfactants were established. Succinate surfactants behave as longer alkyl chain surfactants than their azelate counterparts, meaning that these last ones probably adopt a more folded conformation, with the ester function more frequently present at the micelle surface. This conformation would result in a rougher micelle surface, making it slightly less easy for micelles to pack in liquid crystalline phases. It was also shown that the tendency to adopt a more folded conformation and to form smaller micelles is ranked in this order: monomenthyl>monocitronellyl>monodecyl.

  14. Succinate and Lactate Production from Euglena gracilis during Dark, Anaerobic Conditions

    PubMed Central

    Tomita, Yuko; Yoshioka, Kazumasa; Iijima, Hiroko; Nakashima, Ayaka; Iwata, Osamu; Suzuki, Kengo; Hasunuma, Tomohisa; Kondo, Akihiko; Hirai, Masami Yokota; Osanai, Takashi

    2016-01-01

    Euglena gracilis is a eukaryotic, unicellular phytoflagellate that has been widely studied in basic science and applied science. Under dark, anaerobic conditions, the cells of E. gracilis produce a wax ester that can be converted into biofuel. Here, we demonstrate that under dark, anaerobic conditions, E. gracilis excretes organic acids, such as succinate and lactate, which are bulk chemicals used in the production of bioplastics. The levels of succinate were altered by changes in the medium and temperature during dark, anaerobic incubation. Succinate production was enhanced when cells were incubated in CM medium in the presence of NaHCO3. Excretion of lactate was minimal in the absence of external carbon sources, but lactate was produced in the presence of glucose during dark, anaerobic incubation. E. gracilis predominantly produced L-lactate; however, the percentage of D-lactate increased to 28.4% in CM medium at 30°C. Finally, we used a commercial strain of E. gracilis for succinate production and found that nitrogen-starved cells, incubated under dark, anaerobic conditions, produced 869.6 mg/L succinate over a 3-day incubation period, which was 70-fold higher than the amount produced by nitrogen-replete cells. This is the first study to demonstrate organic acid excretion by E. gracilis cells and to reveal novel aspects of primary carbon metabolism in this organism. PMID:28066371

  15. Synthesis and Monolayer Behaviors of Succinic Acid-Type Gemini Surfactants Containing Semifluoroalkyl Groups.

    PubMed

    Kawase, Tokuzo; Nagase, Youhei; Oida, Tatsuo

    2016-01-01

    In this work, novel succinic acid-type gemini surfactants containing semifluoroalkyl groups, dl- and meso-2,3-bis[Rf-(CH2)n]-succinic acids (Rf = C4F9, C6F13, C8F17; n = 2, 9), were successfully synthesized, and the effects of Rf, methylene chain length (n), and stereochemistry on their monolayer behaviors were studied. Critical micelle concentrations (CMC) of dl- and meso-2,3-bis[C4F9(CH2)9]-succinic acids were one order of magnitude smaller than that of the corresponding 1+1 type surfactant, C4F9(CH2)9COOH. From surface pressure-area (π-A) measurements, the lift-off areas of the geminis were found to decrease in the order C4F9 ≥ C6F13 > C8F17, regardless of methylene chain length and stereochemistry. The zero-pressure molecular areas of the geminis were twice those of the corresponding 1+1 type surfactants. Based on Gibbs compression modulus analysis, it was clarified that 2,3-bis[C8F17(CH2)n]-succinic gemini with short methylene chains (n = 2) would form more rigid monolayers than those having long methylene chains (n = 9). Unlike for 2,3-bis(alkyl)-succinic acids, the effects of stereochemistry on the monolayer behavior of semifluoroalkylated geminis were small.

  16. Kinetics of the extraction of succinic acid with tri-n-octylamine in 1-octanol solution.

    PubMed

    Jun, Young-Si; Huh, Yun Suk; Hong, Won Hi; Hong, Yeon Ki

    2005-01-01

    Kinetic studies for the extraction of succinic acid from aqueous solution with 1-octanol solutions of tri-n-octylamine (TOA) were carried out using a stirred cell with a microporous hydrophobic membrane. The interfacial concentrations of species were correlated and thus the intrinsic kinetics was obtained. The overall extraction process was controlled by the chemical reaction at or near the interface between the aqueous and organic phases. The formation reaction of succinic acid-TOA complex was found to be first order with respect to the concentration of succinic acid in the aqueous phase and the order of 0.5 with respect to that of TOA in the organic phase with a rate constant of (3.14 +/- 0.6) x 10(-8) m(2.5) x mol(-0.5) x s(-1). The dissociation reaction of succinic acid-TOA complex was found to be the second-order with respect to that of succinic acid-TOA complex in the organic phase and the order of -2 with respect to that of TOA in the organic phase with a rate constant of (1.44 +/- 1.4) x 10(-4) mol x m(-2) x s(-1).

  17. Effect of succinic acid and tween-80 on glucuronidation of 2-ethyl-6-methyl-3-hydroxypyridine.

    PubMed

    Baranov, P A; Kravtsova, O U; Sariev, A K; Sherdev, V P

    2008-07-01

    We studied the effect of succinic acid on the process of glucuronidation of 2-ethyl-6-methyl-3-hydroxypyridine after peroral and intraperitoneal administration in the form of succinate or a base. Since the basic form of 2-ethyl-6-methyl-3-hydroxypyridine is insoluble in water, it was administered in 5% Tween-80. It was necessary to evaluate also the effect of Tween-80 on glucuronidation of 2-ethyl-6-methyl-3-hydroxypyridine in different administration routes. Quantitative assay of glucuronidated fractions was performed by the method of reversed-phase HPLC with fluorometrical detection. The detection limit for this method was 10 ng/ml. We confirmed that the major excretion pathway for 2-ethyl-6-methyl-3-hydroxypyridine is conjugation with glucuronic acid. It was found that succinic acid increased excretion of glucuronidated metabolite after both peroral and intraperitoneal administration of 2-ethyl-6-methyl-3-hydroxypyridine in the form of succinate and base in 5% Tween-80. The effect of Tween-80 was detected only after peroral administration, which was probably related to its effect on absorption of this compound. Tween-80 increased excretion of glucuronate after peroral administration of 2-ethyl-6-methyl-3-hydroxypyridine in the form of succinate and in 5% Tween solution.

  18. Pretreatment of spent sulphite liquor via ultrafiltration and nanofiltration for bio-based succinic acid production.

    PubMed

    Pateraki, Chrysanthi; Ladakis, Dimitrios; Stragier, Lutgart; Verstraete, Willy; Kookos, Ioannis; Papanikolaou, Seraphim; Koutinas, Apostolis

    2016-09-10

    Ultrafiltration and nanofiltration of spent sulphite liquor (SSL) has been employed to evaluate the simultaneous production of lignosulphonates and bio-based succinic acid using the bacterial strains Actinobacillus succinogenes and Basfia succiniciproducens. Ultrafiltration with membranes of 10, 5 and 3kDa molecular weight cut-off results in significant losses of lignosulphonates (26-50%) in the permeate stream, while nanofiltration using membrane with 500Da molecular weight cut-off results in high retention yields of lignosulphonates (95.6%) in the retentate stream. Fed-batch bioreactor cultures using permeates from ultrafiltrated SSL resulted in similar succinic acid concentration (27.5g/L) and productivity (0.4g/L/h) by both strains. When permeates from nanofiltrated SSL were used, the strain B. succiniciproducens showed the highest succinic acid concentration (33.8g/L), yield (0.58g per g of consumed sugars) and productivity (0.48g/L/h). The nanofiltration of 1t of thick spent sulphite liquor could lead to the production of 306.3kg of lignosulphonates and 52.7kg of succinic acid, whereas the ultrafiltration of 1t of thick spent sulphite liquor using a 3kDa membrane could result in the production of 237kg of lignosulphonates and 71.8kg of succinic acid when B. succiniproducens is used in both cases.

  19. 21 CFR 184.1721 - Sodium acetate.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Sodium acetate. 184.1721 Section 184.1721 Food and....1721 Sodium acetate. (a) Sodium acetate (C2H3O2Na, CAS Reg. No. 127-09-3 or C2H3O2Na·3H2O, CAS Reg. No. 6131-90-4) is the sodium salt of acetic acid and occurs naturally in plant and animal tissues....

  20. Concurrent non-ketotic hyperglycinemia and propionic acidemia in an eight year old boy.

    PubMed

    Kruszka, Paul S; Kirmse, Brian; Zand, Dina J; Cusmano-Ozog, Kristina; Spector, Elaine; Van Hove, Johan L; Chapman, Kimberly A

    2014-01-01

    This is the first reported case of a patient with both non-ketotic hyperglycinemia and propionic acidemia. At 2 years of age, the patient was diagnosed with non-ketotic hyperglycinemia by elevated glycine levels and mutations in the GLDC gene (paternal allele: c.1576_1577insC delT and c.1580delGinsCAA; p.S527Tfs*13, and maternal allele: c.1819G>A; p.G607S). At 8 years of age after having been placed on ketogenic diet, he became lethargic and had severe metabolic acidosis with ketonuria. Urine organic acid analysis and plasma acylcarnitine profile were consistent with propionic acidemia. He was found to have an apparently homozygous mutation in the PCCB gene: c.49C>A; p.Leu17Met. The patient was also treated with natural protein restriction, carnitine, biotin, and thiamine and had subjective and biochemical improvement.

  1. 21 CFR 582.1721 - Sodium acetate.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Sodium acetate. 582.1721 Section 582.1721 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS....1721 Sodium acetate. (a) Product. Sodium acetate. (b) Conditions of use. This substance is...

  2. 21 CFR 582.1721 - Sodium acetate.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Sodium acetate. 582.1721 Section 582.1721 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS....1721 Sodium acetate. (a) Product. Sodium acetate. (b) Conditions of use. This substance is...

  3. 21 CFR 582.1721 - Sodium acetate.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Sodium acetate. 582.1721 Section 582.1721 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS....1721 Sodium acetate. (a) Product. Sodium acetate. (b) Conditions of use. This substance is...

  4. 21 CFR 582.1721 - Sodium acetate.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Sodium acetate. 582.1721 Section 582.1721 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS....1721 Sodium acetate. (a) Product. Sodium acetate. (b) Conditions of use. This substance is...

  5. 21 CFR 582.1721 - Sodium acetate.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Sodium acetate. 582.1721 Section 582.1721 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS....1721 Sodium acetate. (a) Product. Sodium acetate. (b) Conditions of use. This substance is...

  6. 21 CFR 582.1005 - Acetic acid.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Acetic acid. 582.1005 Section 582.1005 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS....1005 Acetic acid. (a) Product. Acetic acid. (b) Conditions of use. This substance is...

  7. 21 CFR 582.1005 - Acetic acid.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Acetic acid. 582.1005 Section 582.1005 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS....1005 Acetic acid. (a) Product. Acetic acid. (b) Conditions of use. This substance is...

  8. 21 CFR 184.1005 - Acetic acid.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Acetic acid. 184.1005 Section 184.1005 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) DIRECT FOOD....1005 Acetic acid. (a) Acetic acid (C2H4O2, CAS Reg. No. 64-19-7) is known as ethanoic acid. It...

  9. 21 CFR 582.1005 - Acetic acid.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Acetic acid. 582.1005 Section 582.1005 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS....1005 Acetic acid. (a) Product. Acetic acid. (b) Conditions of use. This substance is...

  10. 21 CFR 582.1005 - Acetic acid.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Acetic acid. 582.1005 Section 582.1005 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS....1005 Acetic acid. (a) Product. Acetic acid. (b) Conditions of use. This substance is...

  11. 21 CFR 582.1005 - Acetic acid.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Acetic acid. 582.1005 Section 582.1005 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS....1005 Acetic acid. (a) Product. Acetic acid. (b) Conditions of use. This substance is...

  12. 21 CFR 522.2476 - Trenbolone acetate.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... days. (A) 140 milligrams (mg) trenbolone acetate (one implant consisting of 7 pellets, each pellet containing 20 mg trenbolone acetate) per implant dose. (B) 140 mg trenbolone acetate (one implant consisting... 29 mg tylosin tartrate) per implant dose. (ii) Indications for use. For improved feed...

  13. 21 CFR 522.2476 - Trenbolone acetate.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... days. (A) 140 milligrams (mg) trenbolone acetate (one implant consisting of 7 pellets, each pellet containing 20 mg trenbolone acetate) per implant dose. (B) 140 mg trenbolone acetate (one implant consisting... 29 mg tylosin tartrate) per implant dose. (ii) Indications for use. For improved feed...

  14. Photochemistry of 2-nitrobenzylidene acetals.

    PubMed

    Sebej, Peter; Solomek, Tomás; Hroudná, L'ubica; Brancová, Pavla; Klán, Petr

    2009-11-20

    Photolysis of dihydroxy compounds (diols) protected as 2-nitrobenzylidene acetals (ONBA) and subsequent acid- or base-catalyzed hydrolysis of the 2-nitrosobenzoic acid ester intermediates result in an efficient and high-yielding release of the substrates. We investigated the scope and limitations of ONBA photochemistry and expanded upon earlier described two-step procedures to show that the protected diols of many structural varieties can also be liberated in a one-pot procedure. In view of the fact that the acetals of nonsymmetrically substituted diols are converted into one of the corresponding 2-nitrosobenzoic acid ester isomers with moderate to high regioselectivity, the mechanism of their formation was studied using various experimental techniques. The experimental data were found to be in agreement with DFT-based quantum chemical calculations that showed the preferential cleavage occurs on the acetal C-O bond in the vicinity of more electron-withdrawing (or less electron-donating) groups. The study also revealed considerable complexity in the cleavage mechanism and that the structural variations in the substrate can significantly alter the reaction pathway. This deprotection strategy was found to be also applicable for 2-thioethanol when released from the corresponding monothioacetal in the presence of a reducing agent, such as ascorbic acid.

  15. Veno-Venous Extracorporeal Membrane Oxygenation for Continuous Renal Replacement in a Neonate with Propionic Acidemia.

    PubMed

    Gander, Jeffrey W; Rhone, Erika T; Wilson, William G; Barcia, John P; Sacco, Melissa J

    2017-03-01

    The usual indications for extra corporeal membrane oxygenation (ECMO) are for respiratory or cardiac failure. Although continuous renal replacement therapy (CRRT) is frequently used when patients are on ECMO, the need for CRRT as the primary indication for ECMO is rare. A case of a neonate placed onto veno-venous ECMO for the use of CRRT to treat hyperammonemia from propionic acidemia is presented.

  16. Continuous propionate production from whey permeate using a novel fibrous bed bioreactor.

    PubMed

    Yang, S T; Zhu, H; Li, Y; Hong, G

    1994-05-01

    Continuous production of propionate from whey lactose by Propionibacterium acidipropionici immobilized in a novel fibrous bed bioreactor was studied. In conventional batch propionic acid fermentation, whey permeate without nutrient supplementation was unable to support cell growth and failed to give satisfactory fermentation results for over 7 days. However, with the fibrous bed bioreactor, a high fermentation rate and high conversion were obtained with plain whey permeate and de-lactose whey permeate. About 2% (wt/vol) propionic acid was obtained from a 4.2% lactose feed at a retention time of 35 to 45 h. The propionic acid yield was approximately 46% (wt/vol) from lactose. The optimal pH for fementation was 6.5, and lower fermentation rates and yields were obtained at lower pH values. The optimal temperature was 30 degrees C, but the temperature effect was not dramatic in the range of 25 to 35 degrees C. Addition of yeast extract and trypticase to whey permeate hastened reactor startup and increased the fermentation rate and product yields, but the addition was not required for long-term reactor performance. The improved fermentation results with the immobilized cell bioreactor can be attributed to the high cell density, approximately 50 g/L, attained in the bioreactor, Cells were immobilized by loose attachement to fiber surfaces and entrapment in the void spaces within the fibrous matrix, thus allowing constant renewal of cells. Consequently, this bioreactor was able to operate continuously for 6 months without encountering any clogging, degeneration, or contamination problems. Compared to conventional batch fermentors, the new bioreactor offers many advantages for industrial fermentation, including a more than 10-fold increase in productivity, acceptance of low-nutrient feedstocks such as whey permeate, and resistance to contamination. (c) 1994 John Wiley & Sons, Inc.

  17. Topical clobetasol propionate in the treatment of psoriasis: a review of newer formulations.

    PubMed

    Feldman, Steven R; Yentzer, Brad A

    2009-01-01

    Ultrapotent topical corticosteroids are the mainstay of psoriasis treatment, used either alone or in combination with a topical vitamin D analog. Traditionally used in an ointment vehicle for psoriasis, clobetasol propionate 0.05% is also available in spray, foam, lotion, and shampoo formulations, which may provide for improved convenience and acceptance in many patients with similar efficacy, safety, and tolerability as the traditional ointment and cream formulations. To compare newer formulations with traditional ointment and cream formulations, we performed a systematic review of the literature. Search terms included 'clobetasol propionate,' in combination with 'psoriasis,' 'vasoconstriction,' 'vasoconstrictor,' or 'absorption' for each of the four vehicles ('spray,' 'foam,' 'lotion,' and 'shampoo'). While there are very few direct comparison studies between clobetasol propionate in different vehicles, the efficacy rates (with success defined as clear or almost clear of psoriasis) for more recent formulations are high, with most patients achieving success after 2-4 weeks of treatment in well controlled clinical trials, with response rates that are similar to those with the traditional clobetasol propionate ointment. Small differences in vasoconstrictor potency or cutaneous absorption have been noted among the formulations, but the clinical significance of these observations is difficult to discern. Recent research has emphasized the importance of treatment adherence in the management of psoriasis. Adherence to treatment is likely to be a far more important determinant of success than are small differences in drug delivery, especially in actual clinical use as opposed to the well controlled environment of clinical trials. For patients who prefer a less messy vehicle, adherence and outcomes are likely to be better with the more recent formulations compared with the traditionally recommended ointment.

  18. Production of propionic acid from whey permeate by sequential fermentation, ultrafiltration, and cell recycling.

    PubMed

    Colomban, A; Roger, L; Boyaval, P

    1993-11-05

    This article deals with the production by fermentation of a mycostatic and aromatic food additive based on propionic acid. Membrane bioreactors have been used from laboratory scale up to pilot and industrial production plants. Due to the high cell densities achieved by the sequential recycling mode of operation, a mixed acids solution was rapidly produced from whey permeate. The sterile fermented broth obtained was subsequently concentrated at different levels by evaporation and spray drying according to the projected use. Concentrated Propionibacterium cells (200 g x L(-1) DW) were obtained from the process by periodic bleeds and could be used to good effect as cheese starters, silage preservatives, or probiotics. Propionic acid concentrations from 30 to 40 g x L(-1) were easily achieved with no residual lactose. The highest volumetric productivity was 1.6 g x L(-1) x h(-1) for total acid and 1.2 g x L(-1) x h(-1) for propionic acid with a specific productivity of 0.035 h(-1).

  19. The role of fluticasone propionate/salmeterol combination therapy in preventing exacerbations of COPD

    PubMed Central

    Yawn, Barbara P; Raphiou, Ibrahim; Hurley, Judith S; Dalal, Anand A

    2010-01-01

    Exacerbations contribute significantly to the morbidity of COPD, leading to an accelerated decline in lung function, reduced functional status, reduced health status and quality of life, poorer prognosis and increased mortality. Prevention of exacerbations is thus an important goal of COPD management. In patients with COPD, treatment with a combination of the inhaled corticosteroid fluticasone propionate (250 μg) and the long-acting β2-agonist salmeterol (50 μg) in a single inhaler (250/50 μg) is an effective therapy option that has been shown to reduce the frequency of exacerbations, to improve lung function, dyspnea and health status, and to be relatively cost-effective as a COPD maintenance therapy. Importantly, results of various studies suggest that fluticasone propionate and salmeterol have synergistic effects when administered together that improve their efficacy in controlling symptoms and reducing exacerbations. The present non-systematic review summarizes the role of fluticasone propionate/salmeterol combination therapy in the prevention of exacerbations of COPD and its related effects on lung function, survival, health status, and healthcare costs. PMID:20631816

  20. Increased colonic propionate reduces anticipatory reward responses in the human striatum to high-energy foods123

    PubMed Central

    Byrne, Claire S; Chambers, Edward S; Alhabeeb, Habeeb; Chhina, Navpreet; Preston, Tom; Tedford, Catriona; Fitzpatrick, Julie; Irani, Cherag; Busza, Albert; Garcia-Perez, Isabel; Fountana, Sofia; Holmes, Elaine; Goldstone, Anthony P; Frost, Gary S

    2016-01-01

    Background: Short-chain fatty acids (SCFAs), metabolites produced through the microbial fermentation of nondigestible dietary components, have key roles in energy homeostasis. Animal research suggests that colon-derived SCFAs modulate feeding behavior via central mechanisms. In humans, increased colonic production of the SCFA propionate acutely reduces energy intake. However, evidence of an effect of colonic propionate on the human brain or reward-based eating behavior is currently unavailable. Objectives: We investigated the effect of increased colonic propionate production on brain anticipatory reward responses during food picture evaluation. We hypothesized that elevated colonic propionate would reduce both reward responses and ad libitum energy intake via stimulation of anorexigenic gut hormone secretion. Design: In a randomized crossover design, 20 healthy nonobese men completed a functional magnetic resonance imaging (fMRI) food picture evaluation task after consumption of control inulin or inulin-propionate ester, a unique dietary compound that selectively augments colonic propionate production. The blood oxygen level–dependent (BOLD) signal was measured in a priori brain regions involved in reward processing, including the caudate, nucleus accumbens, amygdala, anterior insula, and orbitofrontal cortex (n = 18 had analyzable fMRI data). Results: Increasing colonic propionate production reduced BOLD signal during food picture evaluation in the caudate and nucleus accumbens. In the caudate, the reduction in BOLD signal was driven specifically by a lowering of the response to high-energy food. These central effects were partnered with a decrease in subjective appeal of high-energy food pictures and reduced energy intake during an ad libitum meal. These observations were not related to changes in blood peptide YY (PYY), glucagon-like peptide 1 (GLP-1), glucose, or insulin concentrations. Conclusion: Our results suggest that colonic propionate production may

  1. Characterization of (R/S)-mecoprop [2-(2-methyl-4-chlorophenoxy) propionic acid]-degrading Alcaligenes sp.CS1 and Ralstonia sp. CS2 isolated from agricultural soils.

    PubMed

    Smejkal, C W; Vallaeys, T; Seymour, F A; Burton, S K; Lappin-Scott, H M

    2001-04-01

    The herbicide mecoprop [2-(2-methyl-4-chlorophenoxy) propionic acid] is widely applied to corn fields in order to control broad-leaved weeds. However, it is often detected in groundwater where it can be a persistent contaminant. Two mecoprop-degrading bacterial strains were isolated from agricultural soils through their capability to degrade (R/S)-mecoprop rapidly. 16S rDNA sequencing of the isolates demonstrated that one was closely related to the genera Alcaligenes sp. (designated CS1) and the other to Ralstonia sp. (designated CS2). Additionally, these isolates demonstrated ability to grow on other related herbicides, including 2,4-D (2,4-dichlorophenoxyacetic acid), MCPA [4-chloro-2-methyl phenoxy acetic acid] and (R/S)-2,4-DP [2-(2,4-dichlorophenoxy)propionic acid] as sole carbon sources. tfdABC gene-specific probes derived from the 2,4-D-degrading Variovorax paradoxus TV1 were used in hybridization analyses to establish whether tfd-like genes are present in mecoprop-degrading bacteria. Hybridization analysis demonstrated that both Alcaligenes sp. CS1 and Ralstonia sp. CS2 harboured tfdA, tfdB and tfdC genes on plasmids that have approximately > 60% sequence similarity to the tfdA, tfdB and tfdC genes of V. paradoxus. It is therefore likely that tfd-like genes may be involved in the degradation of mecoprop, and we are currently investigating this further.

  2. Development of megestrol acetate solid dispersion nanoparticles for enhanced oral delivery by using a supercritical antisolvent process

    PubMed Central

    Ha, Eun-Sol; Kim, Jeong-Soo; Baek, In-hwan; Yoo, Jin-Wook; Jung, Yunjin; Moon, Hyung Ryong; Kim, Min-Soo

    2015-01-01

    In the present study, solid dispersion nanoparticles with a hydrophilic polymer and surfactant were developed using the supercritical antisolvent (SAS) process to improve the dissolution and oral absorption of megestrol acetate. The physicochemical properties of the megestrol acetate solid dispersion nanoparticles were characterized using scanning electron microscopy, differential scanning calorimetry, powder X-ray diffraction, and a particle-size analyzer. The dissolution and oral bioavailability of the nanoparticles were also evaluated in rats. The mean particle size of all solid dispersion nanoparticles that were prepared was <500 nm. Powder X-ray diffraction and differential scanning calorimetry measurements showed that megestrol acetate was present in an amorphous or molecular dispersion state within the solid dispersion nanoparticles. Hydroxypropylmethyl cellulose (HPMC) solid dispersion nanoparticles significantly increased the maximum dissolution when compared with polyvinylpyrrolidone K30 solid dispersion nanoparticles. The extent and rate of dissolution of megestrol acetate increased after the addition of a surfactant into the HPMC solid dispersion nanoparticles. The most effective surfactant was Ryoto sugar ester L1695, followed by D-α-tocopheryl polyethylene glycol 1000 succinate. In this study, the solid dispersion nanoparticles with a drug:HPMC:Ryoto sugar ester L1695 ratio of 1:2:1 showed >95% rapid dissolution within 30 minutes, in addition to good oral bioavailability, with approximately 4.0- and 5.5-fold higher area under the curve (0–24 hours) and maximum concentration, respectively, than raw megestrol acetate powder. These results suggest that the preparation of megestrol acetate solid dispersion nanoparticles using the supercritical antisolvent process is a promising approach to improve the dissolution and absorption properties of megestrol acetate. PMID:26345723

  3. Development of megestrol acetate solid dispersion nanoparticles for enhanced oral delivery by using a supercritical antisolvent process.

    PubMed

    Ha, Eun-Sol; Kim, Jeong-Soo; Baek, In-Hwan; Yoo, Jin-Wook; Jung, Yunjin; Moon, Hyung Ryong; Kim, Min-Soo

    2015-01-01

    In the present study, solid dispersion nanoparticles with a hydrophilic polymer and surfactant were developed using the supercritical antisolvent (SAS) process to improve the dissolution and oral absorption of megestrol acetate. The physicochemical properties of the megestrol acetate solid dispersion nanoparticles were characterized using scanning electron microscopy, differential scanning calorimetry, powder X-ray diffraction, and a particle-size analyzer. The dissolution and oral bioavailability of the nanoparticles were also evaluated in rats. The mean particle size of all solid dispersion nanoparticles that were prepared was <500 nm. Powder X-ray diffraction and differential scanning calorimetry measurements showed that megestrol acetate was present in an amorphous or molecular dispersion state within the solid dispersion nanoparticles. Hydroxypropylmethyl cellulose (HPMC) solid dispersion nanoparticles significantly increased the maximum dissolution when compared with polyvinylpyrrolidone K30 solid dispersion nanoparticles. The extent and rate of dissolution of megestrol acetate increased after the addition of a surfactant into the HPMC solid dispersion nanoparticles. The most effective surfactant was Ryoto sugar ester L1695, followed by D-α-tocopheryl polyethylene glycol 1000 succinate. In this study, the solid dispersion nanoparticles with a drug:HPMC:Ryoto sugar ester L1695 ratio of 1:2:1 showed >95% rapid dissolution within 30 minutes, in addition to good oral bioavailability, with approximately 4.0- and 5.5-fold higher area under the curve (0-24 hours) and maximum concentration, respectively, than raw megestrol acetate powder. These results suggest that the preparation of megestrol acetate solid dispersion nanoparticles using the supercritical antisolvent process is a promising approach to improve the dissolution and absorption properties of megestrol acetate.

  4. The effect of gamma radiation on some succinic acid derivatives in the solid state

    NASA Astrophysics Data System (ADS)

    Sütçü, Kerem; Osmanoǧlu, Y. Emre

    2017-01-01

    2,2-dimethyl succinic acid, 2,3-dimethyl succinic acid and monomethyl succinate were exposed to gamma radiation in the form of powder. EPR measurements were carried out to investigate the free radicals produced in all of them, following irradiation. Three of the radical species formed after irradiation were identified and spectroscopic parameters were discussed thereafter. The radical species were attributed to the ĊHCH2, HOOCCH(CH3)2ĊCOOH and H3COOCCH2ĊHCOOH radicals, respectively. The hyperfine splitting constants for all radicals were confirmed by the simulation of the experimental spectra. The radiation sensitivity of the samples was mainly attributed to the EPR line properties of stable radicals.

  5. Characterization of the Membrane-Bound Succinic Dehydrogenase of Micrococcus lysodeikticus

    PubMed Central

    Pollock, Jerry J.; Linder, Regina; Salton, Milton R. J.

    1971-01-01

    The occurrence of succinic dehydrogenase [succinic:(acceptor) oxidoreductase, EC 1.3.99.1] in membrane fractions of Micrococcus lysodeikticus was investigated. The enzyme could be purified 10-fold, by deoxycholate treatment. Butanol extraction of membranes yielded an active fraction, nonsedimentable at 130,000 × g for 2 hr and altered in its phospholipid content relative to membranes. The activity of the enzyme in particulate preparations was decreased in the presence of competitive inhibitors and by compounds known to react with iron, sulfhydryl groups, and flavine. In this respect, the bacterial succinic dehydrogenase is similar to the enzyme derived from yeast and mammalian sources. In certain membrane fractions, Ca2+ and Mg2+ exhibited inhibitory effects whereas Triton X-100 caused activation. The enzyme could also be activated by substrate. In the phenazine reductase assay, incomplete reduction of electron acceptor was observed upon addition of divalent cations and iron binding agents. Images PMID:4327510

  6. Solid/liquid phase diagram of the ammonium sulfate/succinic acid/water system.

    PubMed

    Pearson, Christian S; Beyer, Keith D

    2015-05-14

    We have studied the low-temperature phase diagram and water activities of the ammonium sulfate/succinic acid/water system using differential scanning calorimetry and infrared spectroscopy of thin films. Using the results from our experiments, we have mapped the solid/liquid ternary phase diagram, determined the water activities based on the freezing point depression, and determined the ice/succinic acid phase boundary as well as the ternary eutectic composition and temperature. We also compared our results to the predictions of the extended AIM aerosol thermodynamics model (E-AIM) and found good agreement for the ice melting points in the ice primary phase field of this system; however, differences were found with respect to succinic acid solubility temperatures. We also compared the results of this study with those of previous studies that we have published on ammonium sulfate/dicarboxylic acid/water systems.

  7. On-line sample treatment and FT-IR determination of doxylamine succinate in pharmaceuticals.

    PubMed

    Ventura-Gayete, Josep F; de la Guardia, Miguel; Garrigues, Salvador

    2006-12-15

    A low solvent consumption method for Fourier transform infrared spectroscopy (FT-IR) determination of doxylamine succinate in pharmaceuticals has been developed. The analyte was continuous and selectively extracted with a 13% (v/v) ethanol:chloroform solvent mixture, recirculating the solvent through the sample and monitoring the process by FT-IR. Doxylamine succinate was determined by on-line standard addition measuring the peak area in the regions 1730-1710 and 1485-1462cm(-1) corrected with a two-point baseline established between 2000 and 1800cm(-1). This new method implies low volumes of chloroformic solvent mixture, only 2.6mL per sample, in front of classical batch FT-IR methods, improving analytical efficiency and reducing waste generation. The on-line extraction and standard addition determination of doxylamine succinate allowed a throughput of 10h(-1).

  8. Biliverdin amides reveal roles for propionate side chains in bilin reductase recognition and in holophytochrome assembly and photoconversion†

    PubMed Central

    Shang, Lixia; Rockwell, Nathan C.; Martin, Shelley S.; Lagarias, J. Clark

    2010-01-01

    Linear tetrapyrroles (bilins) perform important antioxidant and light harvesting functions in cells from bacteria to humans. To explore the role of the propionate moieties in bilin metabolism, we report the semisynthesis of mono- and di-amides of biliverdin IXα and those of its non-natural XIIIα isomer. Initially, these were examined as substrates of two types of NADPH-dependent biliverdin reductase, BVR and BvdR, and of the representative ferredoxin-dependent bilin reductase, phycocyanobilin:ferredoxin oxidoreductase (PcyA). Our studies indicate that the NADPH-dependent biliverdin reductases are less accommodating to amidation of the propionic acid sidechains of biliverdin IXα than PcyA, which does not require free carboxylic acid sidechains to yield its phytobilin product, phycocyanobilin. Bilin amides were also assembled with BV-type and phytobilin-type apophytochromes, demonstrating a role for the 8-propionate in formation of the spectroscopically native Pr dark states of these biliprotein photosensors. Neither ionizable propionate sidechain proved essential to primary photoisomerization for both classes of phytochromes, but an unsubstituted 12-propionate was required for full photointerconversion of phytobilin-type phytochrome Cph1. Taken together, these studies provide insight into the roles of the ionizable propionate sidechains in substrate discrimination by two bilin reductase families while further underscoring the mechanistic differences between the photoconversions of BV-type and phytobilin-type phytochromes. PMID:20565135

  9. A large genomic island allows Neisseria meningitidis to utilize propionic acid, with implications for colonization of the human nasopharynx.

    PubMed

    Catenazzi, Maria Chiara E; Jones, Helen; Wallace, Iain; Clifton, Jacqueline; Chong, James P J; Jackson, Matthew A; Macdonald, Sandy; Edwards, James; Moir, James W B

    2014-07-01

    Neisseria meningitidis is an important human pathogen that is capable of killing within hours of infection. Its normal habitat is the nasopharynx of adult humans. Here we identify a genomic island (the prp gene cluster) in N. meningitidis that enables this species to utilize propionic acid as a supplementary carbon source during growth, particularly under nutrient poor growth conditions. The prp gene cluster encodes enzymes for a methylcitrate cycle. Novel aspects of the methylcitrate cycle in N. meningitidis include a propionate kinase which was purified and characterized, and a putative propionate transporter. This genomic island is absent from the close relative of N. meningitidis, the commensal Neisseria lactamica, which chiefly colonizes infants not adults. We reason that the possession of the prp genes provides a metabolic advantage to N. meningitidis in the adult oral cavity, which is rich in propionic acid-generating bacteria. Data from classical microbiological and sequence-based microbiome studies provide several lines of supporting evidence that N. meningitidis colonization is correlated with propionic acid generating bacteria, with a strong correlation between prp-containing Neisseria and propionic acid generating bacteria from the genus Porphyromonas, and that this may explain adolescent/adult colonization by N. meningitidis.

  10. Effects of Excess Succinate and Retrograde Control of Metabolite Accumulation in Yeast Tricarboxylic Cycle Mutants*

    PubMed Central

    Lin, An-Ping; Anderson, Sondra L.; Minard, Karyl I.; McAlister-Henn, Lee

    2011-01-01

    Cellular and mitochondrial metabolite levels were measured in yeast TCA cycle mutants (sdh2Δ or fum1Δ) lacking succinate dehydrogenase or fumarase activities. Cellular levels of succinate relative to parental strain levels were found to be elevated ∼8-fold in the sdh2Δ mutant and ∼4-fold in the fum1Δ mutant, and there was a preferential increase in mitochondrial levels in these mutant strains. The sdh2Δ and fum1Δ strains also exhibited 3–4-fold increases in expression of Cit2, the cytosolic form of citrate synthase that functions in the glyoxylate pathway. Co-disruption of the SFC1 gene encoding the mitochondrial succinate/fumarate transporter resulted in higher relative mitochondrial levels of succinate and in substantial reductions of Cit2 expression in sdh2Δsfc1Δ and fum1Δsfc1Δ strains as compared with sdh2Δ and fum1Δ strains, suggesting that aberrant transport of succinate out of mitochondria mediated by Sfc1 is related to the increased expression of Cit2 in sdh2Δ and fum1Δ strains. A defect (rtg1Δ) in the yeast retrograde response pathway, which controls expression of several mitochondrial proteins and Cit2, eliminated expression of Cit2 and reduced expression of NAD-specific isocitrate dehydrogenase (Idh) and aconitase (Aco1) in parental, sdh2Δ, and fum1Δ strains. Concomitantly, co-disruption of the RTG1 gene reduced the cellular levels of succinate in the sdh2Δ and fum1Δ strains, of fumarate in the fum1Δ strain, and citrate in an idhΔ strain. Thus, the retrograde response is necessary for maintenance of normal flux through the TCA and glyoxylate cycles in the parental strain and for metabolite accumulation in TCA cycle mutants. PMID:21841001

  11. Biokinetics and bacterial communities of propionate oxidizing bacteria in phased anaerobic sludge digestion systems.

    PubMed

    Zamanzadeh, Mirzaman; Parker, Wayne J; Verastegui, Yris; Neufeld, Josh D

    2013-03-15

    Phased anaerobic digestion is a promising technology and may be a potential source of bio-energy production. Anaerobic digesters are widely used for sewage sludge stabilization and thus a better understanding of the microbial process and kinetics may allow increased volatile solids reduction and methane production through robust process operation. In this study, we analyzed the impact of phase separation and operational conditions on the bio-kinetic characteristics and communities of bacteria associated with four phased anaerobic digestion systems. In addition to significant differences between bacterial communities associated with different digester operating temperatures, our results also revealed that bacterial communities in the phased anaerobic digestion systems differed between the 1st and 2nd phase digesters and we identified strong community composition correlations with several measured physicochemical parameters. The maximum specific growth rates of propionate oxidizing bacteria (POB) in the mesophilic and thermophilic 1st phases were 11 and 23.7 mgCOD mgCOD(-1) d(-1), respectively, while those of the mesophilic and thermophilic 2nd-phase digesters were 6.7 and 18.6 mgCOD mgCOD(-1) d(-1), respectively. Hence, the biokinetic characteristics of the POB population were dependent on the digester loading. In addition, we observed that the temperature dependency factor (θ) values were higher for the less heavily loaded digesters as compared to the values obtained for the 1st-phase digesters. Our results suggested the appropriate application of two sets of POB bio-kinetic that reflect the differing growth responses as a function of propionate concentration (and/or organic loading rates). Also, modeling acetogenesis in phased anaerobic sludge digestion systems will be improved considering a population shift in separate phases. On the basis of the bio-kinetic values estimated in various digesters, high levels of propionate in the thermophilic digesters may be

  12. The Mitochondrial Chaperone TRAP1 Promotes Neoplastic Growth by Inhibiting Succinate Dehydrogenase

    PubMed Central

    Sciacovelli, Marco; Guzzo, Giulia; Morello, Virginia; Frezza, Christian; Zheng, Liang; Nannini, Nazarena; Calabrese, Fiorella; Laudiero, Gabriella; Esposito, Franca; Landriscina, Matteo; Defilippi, Paola; Bernardi, Paolo; Rasola, Andrea

    2013-01-01

    Summary We report that the mitochondrial chaperone TRAP1, which is induced in most tumor types, is required for neoplastic growth and confers transforming potential to noncancerous cells. TRAP1 binds to and inhibits succinate dehydrogenase (SDH), the complex II of the respiratory chain. The respiratory downregulation elicited by TRAP1 interaction with SDH promotes tumorigenesis by priming the succinate-dependent stabilization of the proneoplastic transcription factor HIF1α independently of hypoxic conditions. These findings provide a mechanistic clue to explain the switch to aerobic glycolysis of tumors and identify TRAP1 as a promising antineoplastic target. PMID:23747254

  13. Poly(butylene succinate) and its copolymers: research, development and industrialization.

    PubMed

    Xu, Jun; Guo, Bao-Hua

    2010-11-01

    Poly(butylene succinate) (PBS) and its copolymers are a family of biodegradable polymers with excellent biodegradability, thermoplastic processability and balanced mechanical properties. In this article, production of the monomers succinic acid and butanediol, synthesis, processing and properties of PBS and its copolymers are reviewed. The physical properties and biodegradation rate of PBS materials can be varied in a wide range through copolymerization with different types and various contents of monomers. PBS has a wide temperature window for thermoplastic processing, which makes the resin suitable for extrusion, injection molding, thermoforming and film blowing. Finally, we summarized industrialization and applications of PBS.

  14. A statistical approach to study the interactive effects of process parameters on succinic acid production from Bacteroides fragilis.

    PubMed

    Isar, Jasmine; Agarwal, Lata; Saran, Saurabh; Kaushik, Rekha; Saxena, Rajendra Kumar

    2007-04-01

    A statistical approach response surface methodology (RSM) was used to study the production of succinic acid from Bacteroides fragilis. The most influential parameters for succinic acid production obtained through one-at-a-time method were glucose, tryptone, sodium carbonate, inoculum size and incubation period. These resulted in the production of 5.4gL(-1) of succinic acid in 48h from B. fragilis under anaerobic conditions. Based on these results, a statistical method, face-centered central composite design (FCCCD) falling under RSM was employed for further enhancing the succinic acid production and to monitor the interactive effect of these parameters, which resulted in a more than 2-fold increase in yield (12.5gL(-1) in 24h). The analysis of variance (ANOVA) showed the adequacy of the model and the verification experiments confirmed its validity. On subsequent scale-up in a 10-L bioreactor using conditions optimized through RSM, 20.0gL(-1) of succinic acid was obtained in 24h. This clearly indicated that the model stood valid even on large scale. Thus, the statistical optimization strategy led to an approximately 4-fold increase in the yield of succinic acid. This is the first report on the use of FCCCD to improve succinic acid production from B. fragilis. The present study provides useful information about the regulation of succinic acid synthesis through manipulation of various physiochemical parameters.

  15. Acetic acid recovery from a hybrid biological-hydrothermal treatment process of sewage sludge - a pilot plant study.

    PubMed

    Andrews, J; Dare, P; Estcourt, G; Gapes, D; Lei, R; McDonald, B; Wijaya, N

    2015-01-01

    A two-stage process consisting of anaerobic fermentation followed by sub-critical wet oxidation was used to generate acetic acid from sewage sludge at pilot scale. Volatile fatty acids, dominated by propionic acid, were produced over 4-6 days in the 2,000 L fermentation reactor, which also achieved 31% solids reduction. Approximately 96% of the carbon was retained in solution over the fermentation stage. Using a 200 L wet oxidation reactor operating in batch mode, the second stage achieved 98% volatile suspended solids (VSS) destruction and 67% total chemical oxygen demand (tCOD) destruction. Acetic acid produced in this stage was recalcitrant to further degradation and was retained in solution. The gross yield from VSS was 16% for acetic acid and 21% for volatile fatty acids across the process, higher than reported yields for wet oxidation alone. The pilot plant results showed that 72% of the incoming phosphorus was retained in the solids, 94% of the nitrogen became concentrated in solution and 41% of the carbon was converted to a soluble state, in a more degradable form. Acetic acid produced from the process has the potential to be used to offset ethanol requirements in biological nutrient removal plants.

  16. Assay of prolyl 4-hydroxylase by the chromatographic determination of [14C]succinic acid on ion-exchange minicolumns.

    PubMed Central

    Cunliffe, C J; Franklin, T J; Gaskell, R M

    1986-01-01

    An assay for prolyl 4-hydroxylase (EC 1.14.11.2) is described which measures succinic acid produced during the decarboxylation of 2-oxoglutaric acid in the presence of poly(L-Pro-Gly-L-Pro). [1-14C]Succinic acid was separated from its precursor 2-oxo[5-14C]glutaric acid by using ion-exchange minicolumns. The contamination of succinic acid by 2-oxoglutaric acid was approx. 1%, and the recovery of succinic acid was 100%. Kinetic parameters of prolyl 4-hydroxylase measured by the assay showed good agreement with published values. Our experience indicates that the measurement of prolyl 4-hydroxylase by the production of succinic acid is especially suited to investigations involving large numbers of assays. PMID:3028379

  17. Specific and efficient N-propionylation of histones with propionic acid N-hydroxysuccinimide ester for histone marks characterization by LC-MS.

    PubMed

    Liao, Rijing; Wu, Haiping; Deng, Haibing; Yu, Yanyan; Hu, Min; Zhai, Huili; Yang, Pengyuan; Zhou, Shaolian; Yi, Wei

    2013-02-19

    Histones participate in epigenetic regulation via a variety of dynamic posttranslational modifications (PTMs) on them. Mass spectrometry (MS) has become a powerful tool to investigate histone PTMs. With the bottom-up mass spectrometry approach, chemical derivatization of histones with propionic anhydride or deuterated acetic anhydride followed by trypsin digestion was widely used to block the hydrophilic lysine residues and generate compatible peptides for LC-MS analysis. However, certain severe side reactions (such as acylation on tyrosine or serine) caused by acid anhydrides will lead to a number of analytical issues such as reducing results accuracy and impairing the reproducibility and sensitivity of MS analysis. As an alternative approach, we report a novel derivatization method that utilizes N-hydroxysuccinimide ester to specifically and efficiently derivatize both free and monomethylated amine groups in histones. A competitive inhibiting strategy was implemented in our method to effectively prevent the side reactions. We demonstrated that our method can achieve excellent specificity and efficiency for histones derivatization in a reproducible manner. Using this derivatization method, we succeeded to quantitatively profile the histone PTMs in KMS11 cell line with selective knock out of translocated NSD2 allele (TKO) and the original parental KMS11 cell lines (PAR) (NSD2, a histone methyltransferase that catalyzes the histone H3 K36 methylation), which revealed a significant crosstalk between H3 protein K27 methylation and adjacent K36 methylation.

  18. Short-term safety assessment of clobetasol propionate 0.05% shampoo: hypothalamic-pituitary-adrenal axis suppression, atrophogenicity, and ocular safety in subjects with scalp psoriasis.

    PubMed

    Andres, Philippe; Poncet, Michel; Farzaneh, Sidou; Soto, Pascale

    2006-04-01

    Clobetasol propionate is known to be a very effective treatment for psoriasis; however, its use is limited by potent corticosteroid class related side effects such as hypothalamic-pituitary-adrenal (HPA) axis suppression and atrophogenicity. The aim of this single-center, parallel group, randomized study was to assess the HPA axis suppression potential, atrophogenicity, and ocular tolerability of clobetasol propionate shampoo in 26 patients with scalp psoriasis. Suitable subjects were treated once daily for 4 weeks with clobetasol propionate shampoo, to be rinsed off after 15 minutes or with a leave-on clobetasol propionate gel. The study demonstrated that clobetasol propionate shampoo did not lead to HPA axis suppression or to skin atrophy. Conversely, the gel led to HPA axis suppression and a decrease in skin thickness. Neither formulation had an impact on ocular safety. Despite the short contact application time, the clobetasol propionate shampoo provides similar efficacy results to the gel.

  19. [The answer reaction of system complement on correction of hypoxia of hydazepam and succinic acid].

    PubMed

    Kuznetsova, L N

    2011-01-01

    Investigated functionally activation of human complement in vivo an model of high hypoxia (6-7,5 km) as without correction, so at the phone of medicine hydazepam and succinic acid. Discover that by analysis of the sensitive to complement components one can estimate effects of high hypoxia and her pharmacological correction.

  20. 21 CFR 172.765 - Succistearin (stearoyl propylene glycol hydrogen succinate).

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Succistearin (stearoyl propylene glycol hydrogen succinate). 172.765 Section 172.765 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD ADDITIVES PERMITTED FOR DIRECT ADDITION TO FOOD FOR HUMAN...