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Sample records for agmatine pretreatment protects

  1. Protective mechanism of agmatine pretreatment on RGC-5 cells injured by oxidative stress

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    Y. Iizuka

    2010-04-01

    Full Text Available Agmatine has neuroprotective effects on retinal ganglion cells (RGCs as well as cortical and spinal neurons. It protects RGCs from oxidative stress even when it is not present at the time of injury. As agmatine has high affinity for various cellular receptors, we assessed protective mechanisms of agmatine using transformed RGCs (RGC-5 cell line. Differentiated RGC-5 cells were pretreated with 100 μM agmatine and consecutively exposed to 1.0 mM hydrogen peroxide (H2O2. Cell viability was determined by measuring lactate dehydrogenase (LDH, and the effects of selective alpha 2-adrenergic receptor antagonist yohimbine (0-500 nM and N-methyl-D-aspartic acid (NMDA receptor agonist NMDA (0-100 µM were evaluated. Agmatine’s protective effect was compared to a selective NMDA receptor antagonist MK-801. After a 16-h exposure to H2O2, the LDH assay showed cell loss greater than 50%, which was reduced to about 30% when agmatine was pretreated before injury. Yohimbine almost completely inhibited agmatine’s protective effect, but NMDA did not. In addition, MK-801 (0-100 µM did not significantly attenuate the H2O2-induced cytotoxicity. Our results suggest that neuroprotective effects of agmatine on RGCs under oxidative stress may be mainly attributed to the alpha 2-adrenergic receptor signaling pathway.

  2. The Protective Effect of Agmatine Against Intracerebroventricular Streptozotocin-Induced Memory Impairment in Male Rats

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    Farbood Yaghoub

    2014-07-01

    Full Text Available Introduction: Intracerebroventricular injection of streptozotocin leads to learning and memory impairment. Different mechanisms such as oxidative stress and insulin signaling disruption has been proposed for streptozocin induced learning and memory deterioration. As these changes occur in Alzheimer's disease, this model is widely used to assess Alzheimer's disease. Agmatine is a polyamine derived from L-arginine decarboxylation. Agmatine is shown to have various effects such as neuroprotective role. Therefore, the present study was aimed to assess the plausible protective effect of agmatine against streptozocin induced memory impairment. Methods: Male sprague-dawely rats weighing 200-250 g were used in this study. Within surgery the canules were implanted bilaterally into lateral ventricle. Streptozocin was injected on days 1 and 3 (3 mg/kg in divided doses. Agmatine administration (40 and 80 mg/kg was started from day 4 and continued in an alternate manner till day 14. The animal’s learning and memory capability was assessed on days 15-18 using morris water maze. The animals were trained during 3 days, and on day 4, the probe test was done. In order to assess the effect of drugs on motivation and sensorimotor coordination, a visible platform test was performed after the probe trial. Results: While streptozocin injection led to learning and memory disability, agmatine treatment in dose 80 mg/kg but not 40 mg/kg restored this memory impairment. Conclusion: It seems that agmatine might be beneficial for memory impairment caused by Alzheimer’s disease.

  3. Agmatine Protects against Zymosan-Induced Acute Lung Injury in Mice by Inhibiting NF-κB-Mediated Inflammatory Response

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    Xuanfei Li

    2014-01-01

    Full Text Available Acute lung injury (ALI is characterized by overwhelming lung inflammation and anti-inflammation treatment is proposed to be a therapeutic strategy for ALI. Agmatine, a cationic polyamine formed by decarboxylation of L-arginine, is an endogenous neuromodulator that plays protective roles in diverse central nervous system (CNS disorders. Consistent with its neuromodulatory and neuroprotective properties, agmatine has been reported to have beneficial effects on depression, anxiety, hypoxic ischemia, Parkinson’s disease, and gastric disorder. In this study, we tested the effect of agmatine on the lung inflammation induced by Zymosan (ZYM challenge in mice. We found that agmatine treatment relieved ZYM-induced acute lung injury, as evidenced by the reduced histological scores, wet/dry weight ratio, and myeloperoxidase activity in the lung tissue. This was accompanied by reduced levels of TNF-α, IL-1β, and IL-6 in lung and bronchoalveolar lavage fluid and decreased iNOS expression in lung. Furthermore, agmatine inhibited the phosphorylation and degradation of IκB and subsequently blocked the activation of nuclear factor (NF-κB induced by Zymosan. Taken together, our results showed that agmatine treatment inhibited NF-κB signaling in lungs and protected mice against ALI induced by Zymosan, suggesting agmatine may be a potential safe and effective approach for the treatment of ALI.

  4. Agmatine protects retinal ganglion cells from hypoxia-induced apoptosis in transformed rat retinal ganglion cell line

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    Kim Chan

    2007-10-01

    Full Text Available Abstract Background Agmatine is an endogenous polyamine formed by the decarboxylation of L-arginine. We investigated the protective effects of agmatine against hypoxia-induced apoptosis of immortalized rat retinal ganglion cells (RGC-5. RGC-5 cells were cultured in a closed hypoxic chamber (5% O2 with or without agmatine. Cell viability was determined by lactate dehydrogenase (LDH assay and apoptosis was examined by annexin V and caspase-3 assays. Expression and phosphorylation of mitogen-activated protein kinases (MAPKs; JNK, ERK p44/42, and p38 and nuclear factor-kappa B (NF-κB were investigated by Western immunoblot analysis. The effects of agmatine were compared to those of brain-derived neurotrophic factor (BDNF, a well-known protective neurotrophin for retinal ganglion cells. Results After 48 hours of hypoxic culture, the LDH assay showed 52.3% cell loss, which was reduced to 25.6% and 30.1% when agmatine and BDNF were administered, respectively. This observed cell loss was due to apoptotic cell death, as established by annexin V and caspase-3 assays. Although total expression of MAPKs and NF-κB was not influenced by hypoxic injury, phosphorylation of these two proteins was increased. Agmatine reduced phosphorylation of JNK and NF-κB, while BDNF suppressed phosphorylation of ERK and p38. Conclusion Our results show that agmatine has neuroprotective effects against hypoxia-induced retinal ganglion cell damage in RGC-5 cells and that its effects may act through the JNK and NF-κB signaling pathways. Our data suggest that agmatine may lead to a novel therapeutic strategy to reduce retinal ganglion cell injury related to hypoxia.

  5. Agmatine protects Müller cells from high-concentration glucose-induced cell damage via N-methyl-D-aspartic acid receptor inhibition.

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    Han, Ning; Yu, Li; Song, Zhidu; Luo, Lifu; Wu, Yazhen

    2015-07-01

    Neural injury is associated with the development of diabetic retinopathy. Müller cells provide structural and metabolic support for retinal neurons. High glucose concentrations are known to induce Müller cell activity. Agmatine is an endogenous polyamine, which is enzymatically formed in the mammalian brain and has exhibited neuroprotective effects in a number of experimental models. The aims of the present study were to investigate whether agmatine protects Müller cells from glucose-induced damage and to explore the mechanisms underlying this process. Lactate dehydrogenase activity and tumor necrosis factor-α mRNA expression were significantly reduced in Müller cells exposed to a high glucose concentration, following agmatine treatment, compared with cells not treated with agmatine. In addition, agmatine treatment inhibited glucose-induced Müller cell apoptosis, which was associated with the regulation of Bax and Bcl-2 expression. Agmatine treatment suppressed glucose-induced phosphorylation of mitogen-activated protein kinase (MAPK) protein in Müller cells. The present study demonstrated that the protective effects of agmatine on Müller cells were inhibited by N-methyl-D-aspartic acid (NMDA). The results of the present study suggested that agmatine treatment protects Müller cells from high-concentration glucose-induced cell damage. The underlying mechanisms may relate to the anti-inflammatory and antiapoptotic effects of agmatine, as well as to the inhibition of the MAPK pathway, via NMDA receptor suppression. Agmatine may be of use in the development of novel therapeutic approaches for patients with diabetic retinopathy.

  6. Agmatine protects rat liver from nicotine-induced hepatic damage via antioxidative, antiapoptotic, and antifibrotic pathways.

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    El-Sherbeeny, Nagla A; Nader, Manar A; Attia, Ghalia M; Ateyya, Hayam

    2016-12-01

    Tobacco smoking with its various forms is a global problem with proved hazardous effects to human health. The present work was planned to study the defending role of agmatine (AGM) on hepatic oxidative stress and damage induced by nicotine in rats. Thirty-two rats divided into four groups were employed: control group, nicotine-only group, AGM group, and AGM-nicotine group. Measurements of serum hepatic biochemical markers, lipid profile, and vascular cell adhesion molecule-1 were done. In addition, malondialdehyde (MDA), superoxide dismutase (SOD), glutathione (GSH) activity, and nitrate/nitrite (NOx) levels were estimated in the liver homogenates. Immunohistochemistry for Bax and transforming growth factor beta (TGF-β1) and histopathology of the liver were also included. Data of the study demonstrated that nicotine administration exhibited marked liver deterioration, an increase in liver enzymes, changes in lipid profile, and an elevation in MDA with a decline in levels of SOD, GSH, and NOx (nitrate/nitrite). Also, levels of proapoptotic Bax and profibrotic TGF-β1 showed marked elevation in the liver. AGM treatment to rats in nicotine-only group ameliorated all the previous changes. These findings indicate that AGM could successfully overcome the nicotine-evoked hepatic oxidative stress and tissue injury, apoptosis, and fibrosis.

  7. Agmatine induces gastric protection against ischemic injury by reducing vascular permeability in rats

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    Abeer A Al Masri; Eman El Eter

    2012-01-01

    AIM:To investigate the effect of administration of agmarine (AGM) on gastric protection against ischemia reperfusion (I/R)injury.METHODS:Three groups of rats (6/group); sham,gastric I/R injury,and gastric I/R + AGM (100 mg/kg,i.p.given 15 min prior to gastric ischemia) were recruited.Gastric injury was conducted by ligating celiac artery for 30 rmin and reperfusion for another 30 min.Gastric tissues were histologically studied and immunostained with angiopoietin 1 (Ang-1) and Ang-2.Vascular endothelial growth factor (VEGF) and monocyte chemoattractant protein-1 (MCP-1) were measured in gastric tissue homogenate.To assess whether AKt/phosphatidyl inositol-3-kinase (PI3K) mediated the effect of AGM,an additional group was pretreated with Wortmannin (WM) (inhibitor of Akt/PI3K,15 μg/kg,i.p.),prior to ischemic injury and AGM treatment,and examined histologically and immunostained.Another set of experiments was run to study vascular permeability of the stomach using Evan's blue dye.RESULTS:AGM markedly reduced Evan's blue dye extravasation (3.58 ± 0.975 μg/stomach vs 1.175 ±0.374 μg/stomach,P < 0.05),and VEGF (36.87 ± 2.71 pg/100 mg protein vs 48.4 ± 6.53 pg/100 mg protein,P < 0.05) and MCP-1 tissue level (29.5 ± 7 pg/100 mg protein vs 41.17 ± 10.4 pg/100 mg protein,P < 0.01).It preserved gastric histology and reduced congestion.Ang-1 and Ang-2 immunostaining were reduced in stomach sections of AGM-treated animals.The administration of WM abolished the protective effects of AGM and extensive hemorrhage and ulcerations were seen.CONCLUSION:AGM protects the stomach against I/R injury by reducing vascular permeability and inflammation.This protection is possibly mediated by Akt/PI3K.

  8. Agmatine attenuates silica-induced pulmonary fibrosis.

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    El-Agamy, D S; Sharawy, M H; Ammar, E M

    2014-06-01

    There is a large body of evidence that nitric oxide (NO) formation is implicated in mediating silica-induced pulmonary fibrosis. As a reactive free radical, NO may not only contribute to lung parenchymal tissue injury but also has the ability to combine with superoxide and form a highly reactive toxic species peroxynitrite that can induce extensive cellular toxicity in the lung tissues. This study aimed to explore the effect of agmatine, a known NO synthase inhibitor, on silica-induced pulmonary fibrosis in rats. Male Sprague Dawley rats were treated with agmatine for 60 days following a single intranasal instillation of silica suspension (50 mg in 0.1 ml saline/rat). The results revealed that agmatine attenuated silica-induced lung inflammation as it decreased the lung wet/dry weight ratio, protein concentration, and the accumulation of the inflammatory cells in the bronchoalveolar lavage fluid. Agmatine showed antifibrotic activity as it decreased total hydroxyproline content of the lung and reduced silica-mediated lung inflammation and fibrosis in lung histopathological specimen. In addition, agmatine significantly increased superoxide dismutase (p pulmonary nitrite/nitrate as well as tumor necrosis factor α. Collectively, these results demonstrate the protective effects of agmatine against the silica-induced lung fibrosis that may be attributed to its ability to counteract the NO production, lipid peroxidation, and regulate cytokine effects.

  9. Agmatine Prevents Adaptation of the Hippocampal Glutamate System in Chronic Morphine-Treated Rats.

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    Wang, Xiao-Fei; Zhao, Tai-Yun; Su, Rui-Bin; Wu, Ning; Li, Jin

    2016-12-01

    Chronic exposure to opioids induces adaptation of glutamate neurotransmission, which plays a crucial role in addiction. Our previous studies revealed that agmatine attenuates opioid addiction and prevents the adaptation of glutamate neurotransmission in the nucleus accumbens of chronic morphine-treated rats. The hippocampus is important for drug addiction; however, whether adaptation of glutamate neurotransmission is modulated by agmatine in the hippocampus remains unknown. Here, we found that continuous pretreatment of rats with ascending doses of morphine for 5 days resulted in an increase in the hippocampal extracellular glutamate level induced by naloxone (2 mg/kg, i.p.) precipitation. Agmatine (20 mg/kg, s.c.) administered concurrently with morphine for 5 days attenuated the elevation of extracellular glutamate levels induced by naloxone precipitation. Furthermore, in the hippocampal synaptosome model, agmatine decreased the release and increased the uptake of glutamate in synaptosomes from chronic morphine-treated rats, which might contribute to the reduced elevation of glutamate levels induced by agmatine. We also found that expression of the hippocampal NR2B subunit, rather than the NR1 subunit, of N-methyl-D-aspartate receptors (NMDARs) was down-regulated after chronic morphine treatment, and agmatine inhibited this reduction. Taken together, agmatine prevented the adaptation of the hippocampal glutamate system caused by chronic exposure to morphine, including modulating extracellular glutamate concentration and NMDAR expression, which might be one of the mechanisms underlying the attenuation of opioid addiction by agmatine.

  10. Evidences for the agmatine involvement in antidepressant like effect of bupropion in mouse forced swim test.

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    Kotagale, Nandkishor R; Tripathi, Sunil J; Aglawe, Manish M; Chopde, Chandrabhan T; Umekar, Milind J; Taksande, Brijesh G

    2013-06-01

    Although bupropion has been widely used in the treatment of depression, the precise mechanism of its therapeutic actions is not fully understood. The present study investigated the role of agmatine in an antidepressant like effect of bupropion in mouse forced swim test. The antidepressant like effect of bupropion was potentiated by pretreatment with agmatine (10-20mg/kg, ip) and by the drugs known to increase endogenous agmatine levels in brain viz., l-arginine (40 μg/mouse, icv), an agmatine biosynthetic precursor, ornithine decarboxylase inhibitor, dl-α-difluoromethyl ornithine hydrochloride, DFMO (12.5 μg/mouse, icv), diamine oxidase inhibitor, aminoguanidine (6.5 μg/mouse, icv) and agmatinase inhibitor, arcaine (50 μg/mouse, icv) as well as imidazoline I1 receptor agonists, moxonidine (0.25mg/kg, ip) and clonidine (0.015 mg/kg, ip) and imidazoline I2 receptor agonist, 2-(2-benzofuranyl)-2-imidazoline hydrochloride, 2-BFI (5mg/kg, ip). Conversely, prior administration of I1 receptor antagonist, efaroxan (1mg/kg, ip) and I2 receptor antagonist, idazoxan (0.25mg/kg, ip) blocked the antidepressant like effect of bupropion and its synergistic combination with agmatine. These results demonstrate involvement of agmatine in the antidepressant like effect of bupropion and suggest agmatine and imidazoline receptors as a potential therapeutic target for the treatment of depressive disorders.

  11. Development of a Pseudomonas aeruginosa Agmatine Biosensor

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    Adam Gilbertsen

    2014-10-01

    Full Text Available Agmatine, decarboxylated arginine, is an important intermediary in polyamine production for many prokaryotes, but serves higher functions in eukaryotes such as nitric oxide inhibition and roles in neurotransmission. Pseudomonas aeruginosa relies on the arginine decarboxylase and agmatine deiminase pathways to convert arginine into putrescine. One of the two known agmatine deiminase operons, aguBA, contains an agmatine sensitive TetR promoter controlled by AguR. We have discovered that this promoter element can produce a titratable induction of its gene products in response to agmatine, and utilized this discovery to make a luminescent agmatine biosensor in P. aeruginosa. The genome of the P. aeruginosa lab strain UCBPP-PA14 was altered to remove both its ability to synthesize or destroy agmatine, and insertion of the luminescent reporter construct allows it to produce light in proportion to the amount of exogenous agmatine applied from ~100 nM to 1mM. Furthermore it does not respond to related compounds including arginine or putrescine. To demonstrate potential applications the biosensor was used to detect agmatine in spent supernatants, to monitor the development of arginine decarboxylase over time, and to detect agmatine in the spinal cords of live mice.

  12. Antidepressant-like effect of agmatine is not mediated by serotonin

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    Krass, Maarja; Wegener, Gregers; Vasar, Eero;

    2008-01-01

    tested (50mg/kg) decreased immobility of mice in the forced swimming test. The magnitude of the effect was slightly smaller than that of the tricyclic antidepressant imipramine (15mg/kg). Agmatine did not change the locomotion of mice in the open field. Pretreatment with the tryptophane hydroxylase...

  13. Agmatine improves renal function in gentamicin-induced nephrotoxicity in rats.

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    El-Kashef, Dalia H; El-Kenawi, Asmaa E; Abdel Rahim, Mona; Suddek, Ghada M; Salem, Hatem A

    2016-03-01

    The present study was designed to explore the possible protective effects of agmatine, a known nitric oxide (NO) synthase inhibitor, against gentamicin-induced nephrotoxicity in rats. For this purpose, we quantitatively evaluated gentamicin-induced renal structural and functional alterations using histopathological and biochemical approaches. Furthermore, the effect of agmatine on gentamicin-induced hypersensitivity of urinary bladder rings to acetylcholine (ACh) was evaluated. Twenty-four male Wistar albino rats were randomly divided into 3 groups, namely control, gentamicin (100 mg/kg, i.p.), and gentamicin plus agmatine (40 mg/kg, orally). At the end of the study, all rats were sacrificed and then blood and urine samples and kidneys were taken. Administration of agmatine significantly decreased kidney/body mass ratio, serum creatinine, lactate dehydrogenase (LDH), renal malondialdehyde (MDA), myeloperoxidase (MPO), NO, and tumor necrosis factor-alpha (TNF-α) while it significantly increased creatinine clearance and renal superoxide dismutase (SOD) activity when compared with the gentamicin-treated group. Additionally, agmatine ameliorated tissue morphology as evidenced by histological evaluation and reduced the responses of isolated bladder rings to ACh. Our study indicates that agmatine administration with gentamicin attenuates oxidative-stress associated renal injury by reducing oxygen free radicals and lipid peroxidation, restoring NO level and inhibiting inflammatory mediators such as TNF-α.

  14. Agmatine enhances the antidepressant-like effect of lithium in mouse forced swimming test through NMDA pathway.

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    Mohseni, Gholmreza; Ostadhadi, Sattar; Imran-Khan, Muhammad; Norouzi-Javidan, Abbas; Zolfaghari, Samira; Haddadi, Nazgol-Sadat; Dehpour, Ahmad-Reza

    2017-04-01

    Depression is one the world leading global burdens leading to various comorbidities. Lithium as a mainstay in the treatment of depression is still considered gold standard treatment. Similar to lithium another agent agmatine has also central protective role against depression. Since, both agmatine and lithium modulate various effects through interaction with NMDA receptor, therefore, in current study we aimed to investigate the synergistic antidepressant-like effect of agmatine with lithium in mouse force swimming test. Also to know whether if such effect is due to interaction with NMDA receptor. In our present study we found that when potent dose of lithium (30mg/kg) was administered, it significantly decreased the immobility time. Also, when subeffective dose of agmatine (0.01mg/kg) was coadministered with subeffective dose of lithium (3mg/kg), it potentiated the antidepressant-like effect of subeffective dose of lithium. For the involvement of NMDA receptor in such effect, we administered NMDA receptor antagonist MK-801 (0.05mg/kg) with a combination of subeffective dose of lithium (3mg/kg) and agmatine (0.001mg/kg). A significant antidepressant-like effect was observed. Furthermore, when subeffective dose (50 and 75mg/kg) of NMDA was given it inhibited the synergistic effect of agmatine (0.01mg/kg) with lithium (3mg/kg). Hence, our finding demonstrate that agmatine have synergistic effect with lithium which is mediated by NMDA receptor pathway.

  15. Effects of Agmatine on Depressive-Like Behavior Induced by Intracerebroventricular Administration of 1-Methyl-4-phenylpyridinium (MPP(+)).

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    Moretti, Morgana; Neis, Vivian Binder; Matheus, Filipe Carvalho; Cunha, Mauricio Peña; Rosa, Priscila Batista; Ribeiro, Camille Mertins; Rodrigues, Ana Lúcia S; Prediger, Rui Daniel

    2015-10-01

    Considering that depression is a common non-motor comorbidity of Parkinson's disease and that agmatine is an endogenous neuromodulator that emerges as a potential agent to manage diverse central nervous system disorders, this study investigated the antidepressant-like effect of agmatine in mice intracerebroventricularly (i.c.v.) injected with the dopaminergic neurotoxin 1-methyl-4-phenylpyridinium (MPP(+)). Male C57BL6 mice were treated with agmatine (0.0001, 0.1 or 1 mg/kg) and 60 min later the animals received an i.c.v. injection of MPP(+) (1.8 µg/site). Twenty-four hours after MPP(+) administration, immobility time, anhedonic behavior, and locomotor activity were evaluated in the tail suspension test (TST), splash test, and open field test, respectively. Using Western blot analysis, we investigated the putative modulation of MPP(+) and agmatine on striatal and frontal cortex levels of tyrosine hydroxylase (TH) and brain-derived neurotrophic factor (BDNF). MPP(+) increased the immobility time of mice in the TST, as well as induced an anhedonic-like behavior in the splash test, effects which were prevented by pre-treatment with agmatine at the three tested doses. Neither drug, alone or in combination, altered the locomotor activity of mice. I.c.v. administration of MPP(+) increased the striatal immunocontent of TH, an effect prevented by the three tested doses of agmatine. MPP(+) and agmatine did not alter the immunocontent of BDNF in striatum and frontal cortex. These results demonstrate for the first time the antidepressant-like effects of agmatine in an animal model of depressive-like behavior induced by the dopaminergic neurotoxin MPP(+).

  16. Comparison of agmatine with moxonidine and rilmenidine in morphine dependence in vitro: role of imidazoline I(1) receptors.

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    Li, Fei; Wu, Ning; Su, Rui-Bin; Liu, Yin; Lu, Xin-Qiang; Li, Jin

    2009-06-10

    Moxonidine and rilmenidine are classical imidazoline I(1) receptor agonists, and used as anti-hypertension drugs in clinical practice. Agmatine is an imidazoline I(1) receptor endogenous ligand as well as its agonist, but more and more evidences suggest it has no influence on blood pressure. In the present study we compared the effects of moxonidine, rilmenidine and agmatine in the development of morphine dependence, and investigated the role of imidazoline I(1) receptor in the effects of these agents. Chinese hamster ovary cells co-expressing mu opioid receptor and imidazoline receptor antisera-selected protein (IRAS), the strong candidate for imidazoline I(1) receptor, were used as the cell line. cAMP overshoot, which represents an opioid dependent state in vitro, was measured to study the effects on morphine dependence. siRNA against IRAS was carried out to investigate the role of imidazoline I(1) receptor. Moxonidine and rilmenidine (0.01-10 microM) were ineffective on cAMP level in the cells when given alone, and failed to inhibit chronic morphine exposure, naloxone-precipitated cAMP overshoot when co-pretreated with morphine. Agmatine (0.01-10 microM) by itself was ineffective but co-pretreated with morphine concentration-dependently inhibited chronic morphine exposure, naloxone-precipitated cAMP overshoot in the cells. Furthermore, we found that the inhibitory effect of agmatine (100 nM and 1 microM) on cAMP overshoot was significantly reduced by siRNA against IRAS. This study indicates that agmatine can inhibit the development of morphine dependence in vitro, whereas moxonidine and rilmenidine have no the effect. Imidazoline I(1) receptor plays an important role in agmatine inhibiting morphine dependence.

  17. Anticonvulsive effect of agmatine in mice

    Institute of Scientific and Technical Information of China (English)

    Xin-QiangLu; Rui-BinSu; Xiao-LiWei; YinLiu; JinLi

    2004-01-01

    AIM: The present study was designed to examine the effect of agmatine, the decarboxylated product of L-arginine by L- arginine decarboxylase, on convulsion in the mouse maximal electroshock (MES) test and mouse glutamate-induced convulsion test. METHODS: MES convulsion and glutamate convulsion were respectively induced by an electrical stimulation

  18. The role of two families of bacterial enzymes in putrescine synthesis from agmatine via agmatine deiminase.

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    Landete, José M; Arena, Mario E; Pardo, Isabel; Manca de Nadra, María C; Ferrer, Sergi

    2010-12-01

    Putrescine, one of the main biogenic amines associated to microbial food spoilage, can be formed by bacteria from arginine via ornithine decarboxylase (ODC), or from agmatine via agmatine deiminase (AgDI). This study aims to correlate putrescine production from agmatine to the pathway involving N-carbamoylputrescine formation via AdDI (the aguA product) and N-carbamoylputrescine amidohydrolase (the aguB product), or putrescine carbamoyltransferase (the ptcA product) in bacteria. PCR methods were developed to detect the two genes involved in putrescine production from agmatine. Putrescine production from agmatine could be linked to the aguA and ptcA genes in Lactobacillus hilgardii X1B, Enterococcus faecalis ATCC 11700, and Bacillus cereus ATCC 14579. By contrast Lactobacillus sakei 23K was unable to produce putrescine, and although a fragment of DNA corresponding to the gene aguA was amplified, no amplification was observed for the ptcA gene. Pseudomonas aeruginosa PAO1 produces putrescine and is reported to harbour aguA and aguB genes, responsible for agmatine deiminase and N-carbamoylputrescine amidohydrolase activities. The enzyme from P. aeruginosa PAO1 that converts N-carbamoylputrescine to putrescine (the aguB product) is different from other microorganisms studied (the ptcA product). Therefore, the aguB gene from P. aeruginosa PAO1 could not be amplified with ptcA-specific primers. The aguB and ptcA genes have frequently been erroneously annotated in the past, as in fact these two enzymes are neither homologous nor analogous. Furthermore, the aguA, aguB and ptcA sequences available from GenBank were subjected to phylogenetic analysis, revealing that gram-positive bacteria harboured ptcA, whereas gram-negative bacteria harbour aguB. This paper also discusses the role of the agmatine deiminase system (AgDS) in acid stress resistance.

  19. Characterization and inactivation of an agmatine deiminase from Helicobacter pylori

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    Jones, Justin E.; Causey, Corey P.; Lovelace, Leslie; Knuckley, Bryan; Flick, Heather; Lebioda, Lukasz; Thompson, Paul R. (SC)

    2010-11-12

    Helicobacter pylori encodes a potential virulence factor, agmatine deiminase (HpAgD), which catalyzes the conversion of agmatine to N-carbamoyl putrescine (NCP) and ammonia - agmatine is decarboxylated arginine. Agmatine is an endogenous human cell signaling molecule that triggers the innate immune response in humans. Unlike H. pylori, humans do not encode an AgD; it is hypothesized that inhibition of this enzyme would increase the levels of agmatine, and thereby enhance the innate immune response. Taken together, these facts suggest that HpAgD is a potential drug target. Herein we describe the optimized expression, isolation, and purification of HpAgD (10-30 mg/L media). The initial kinetic characterization of this enzyme has also been performed. Additionally, the crystal structure of wild-type HpAgD has been determined at 2.1 {angstrom} resolution. This structure provides a molecular basis for the preferential deimination of agmatine, and identifies Asp198 as a key residue responsible for agmatine recognition, which has been confirmed experimentally. Information gathered from these studies led to the development and characterization of a novel class of haloacetamidine-based HpAgD inactivators. These compounds are the most potent AgD inhibitors ever described.

  20. Agmatine ameliorates adjuvant induced arthritis and inflammatory cachexia in rats.

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    Taksande, Brijesh G; Gawande, Dinesh Y; Chopde, Chandrabhan T; Umekar, Milind J; Kotagale, Nandkishor R

    2017-02-01

    The present study investigated the pharmacological effect of agmatine in Complete Freud Adjuvant (CFA) induced arthritis and cachexia in rats. The rats were injected with CFA (0.1ml/rat) to induced symptoms of arthritis. Day 8 onwards of CFA administration, rats were injected daily with agmatine for next 7days, and arthritis score, body weights and food intake were monitored daily (g). Since cachexia is known to produce severe inflammation, malnutrition and inhibition of albumin gene expression, we have also monitored the total proteins, albumin, TNF-α and IL-6 levels in arthritic rats and its modulation by agmatine. In the present study, CFA treated rats showed a progressive reduction in both food intake and body weight. In addition analysis of blood serum of arthritis animals showed a significant reduction in proteins and albumin and significant elevation in tumor necrosis factor (TNF)-α and Interleukins (IL)-6. Chronic agmatine (20-40mg/kg, ip) treatment not only attenuated the signs of arthritis but also reverses anorexia and body weight loss in CFA treated rats. In addition, agmatine restored total protein and albumin and reduces TNF-α and IL-6 levels in arthritis rats. These results suggest that agmatine administration can prevent the body weights loss and symptoms of arthritis via inhibition of inflammatory cytokines.

  1. Agmatine reversed mechanical allodynia in a rat model of neuropathic pain

    Institute of Scientific and Technical Information of China (English)

    YANGHong-Ju; ZhAONan; GONGZheng-Hua; YUANWei-Xiou; LIYunFeng; LI-Jin; LUOZhi-Pu

    2004-01-01

    AIM: Agmatine is an endogenous neuromodulator present in the brain and spinal cord, agmatine has both NMDA receptor antagonist and NOS inhibitor activities, which may participate the pathological process in the neuropathic pain. The effect of agmatine on the mechanical allodynia in a rat model of the neuropathic pain was investigated in this experiment.

  2. Protection Against Hepatic Ischemia-reperfusion Injury in Rats by Oral Pretreatment With Quercetin

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    Objective To investigate the possible protection provided by oral quercetin pretreatment against hepatic ischemia-reperfusion injury in rats. Methods The quercetin (0.13 mmol/kg) was orally administrated in 50 min prior to hepatic ischemia-reperfusion injury. Ascorbic acid was also similarly administered. The hepatic content of quercetin was assayed by high performance liquid chromatography (HPLC). Plasma glutamic pyruvic transaminase (GPT), glutamic oxaloacetic transaminase (GOT) activities and malondialdehyde (MDA) concentration were measured as markers of hepatic ischemia-reperfusion injury. Meanwhile, hepatic content of glutathione (GSH), activities of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and xanthine oxidase (XO), total antioxidant capacity (TAOC), contents of reactive oxygen species (ROS) and MDA, DNA fragmentation were also determined. Results Hepatic content of quercetin after intragastric administration of quercetin was increased significantly. The increases in plasma GPT, GOT activities and MDA concentration after hepatic ischemia-reperfusion injury were reduced significantly by pretreatment with quercetin. Hepatic content of GSH and activities of SOD, GSH-Px and TAOC were restored remarkably while the ROS and MDA contents were significantly diminished by quercetin pretreatment after ischemia-reperfusion injury. However, quercetin pretreatment did not reduce significantly hepatic XO activity and DNA fragmentation. Ascorbic acid pretreatment had also protective effects against hepatic ischemia-reperfusion injury by restoring hepatic content of GSH, TAOC and diminishing ROS and MDA formation and DNA fragmentation. Conclusion It is indicated that quercetin can protect the liver against ischemia-reperfusion injury after oral pretreatment and the underlying mechanism is associated with improved hepatic antioxidant capacity.

  3. Focused Review: Agmatine in fermented foods

    Directory of Open Access Journals (Sweden)

    Fernanda eGalgano

    2012-06-01

    Full Text Available Polyamines (PAs are ubiquitous substances considered as bioregulators of numerous cell functions, being involved in cell growth, division and differentiation. These biogenic amines are also involved in tissue repairing and in intracellular signaling; in fact, because of their polycationic character, they interact strongly with membrane phospholipids and may play an important role in the regulation of membrane-linked enzymes. The intracellular polyamines content derives from the simultaneous regulation of their synthesis, catabolism, uptake and elimination; furthermore, PAs are present in all cell types at variable concentrations, but the highest levels are found in rapid-turnover tissues. In addition to spermidine, spermine and putrescine, also agmatine (AGM, deriving from arginine and identified in mammals in the 1990s, belongs to PAs and several studies have reported its possible positive role in secretagogues, neuronal, vascular, metabolic and therapeutic functions. Because of the low arginine decarboxylase activity (ADC in mammalians, the amounts of AGM found in their tissues can be only minimally ascribed to an endogenous de novo synthesis by the ADC, while a substantial AGM portion can be of dietary origin. Several food products contain only small amounts of polyamines, while higher concentrations can be found in fermented foods. PAs could also be considered as indicators of freshness in fish and meat products, being these moieties produced during food storage, thus confirming the main role of microorganisms in their synthesis. Although many biological functions have been attributed to polyamines, high levels of these compounds in foodstuffs can have toxicological effects; however, the safe level of dietary polyamines intake has not yet been established. In this paper the presence of AGM in different foodstuffs is discussed, taking also into account the various factors affecting its presence and concentration.

  4. The protective effect of erythropoietin pretreatment on ischemic acute renal failure in rats

    Institute of Scientific and Technical Information of China (English)

    Jing-Guang Liao; Min-Yan Li; Xiao-Hua Wang; Qiang Xie

    2016-01-01

    Objective: To investigate the protective effect of erythropoietin (EPO) pretreatment on ischemic acute renal failure in rats and its molecular mechanism. Methods: Male Sprague–Dawley rats were selected as experimental animals and they were randomly divided into the sham operation group (sham group), ischemia-reperfusion injury group (IRI group) and EPO pretreatment group (EPO group). Each group had 15 rats. Serum specimens and renal specimens were collected after a IRI model was built for 4, 12 and 24 h. The contents of creatinine, urea nitrogen tumor necrosis factor-alpha (TNF-a), interleukin-1 (IL-1), IL-6 and IL-8 in serum and the contents of TNF-a, IL-1, IL-6, IL-8, toll like receptor 4 (TLR4) and nuclear factor-kappa B (NF-kB) in the kidney tissue were determined. Results: After 4, 12 and 24 h reperfusion, there were differences between the contents of creatinine, urea nitrogen TNF-a, IL-1, IL-6 and IL-8 in serum and the contents of TNF-a, IL-1, IL-6, IL-8, TLR4 and NF-kB in rats of the three groups (P Conclusions: EPO pretreatment can protect the renal function of rats with ischemic acute renal failure by inhibiting the TLR4/NF-kB pathway mediated inflammatory responses.

  5. Agmatine and a cannabinoid agonist, WIN 55212-2, interact to produce a hypothermic synergy.

    Science.gov (United States)

    Rawls, Scott M; Tallarida, Ronald J; Zisk, Jacob

    2006-12-28

    Agmatine blocks morphine withdrawal symptoms and enhances morphine analgesia in rats. Yet, the role of agmatine in the pharmacological effects of other abused drugs has not been investigated. The present study investigates the effect of agmatine administration on the hypothermic response to cannabinoids. Hypothermia is an effective endpoint because cannabinoid agonists produce a rapid, reproducible, and significant decrease in body temperature that is abolished by cannabinoid CB(1) receptor antagonists. WIN 55212-2, a cannabinoid agonist, was administered to rats by itself and with agmatine. WIN 55212-2 (1, 2.5, 5 and 10 mg/kg, i.m.) caused a significant hypothermia. Agmatine (10, 25 and 50 mg/kg, i.p.) was ineffective. For combined administration, agmatine (50 mg/kg, i.p.) enhanced the hypothermic effect of WIN 55212-2 (1, 2.5, 5 and 10 mg/kg, i.m.). The enhancement was strongly synergistic, indicated by a 2.7-fold increase in the relative potency of WIN 55212-2. The central administration of agmatine (25 and 50 mug/rat, i.c.v.) significantly increased the hypothermic effect of WIN 55212-2 (2.5 mg/kg, i.m.). This indicates that agmatine acts through a central mechanism to augment cannabinoid-evoked hypothermia. Idazoxan (2 mg/kg, i.p.), an imidazoline antagonist, blocked the enhancement by agmatine, thus suggesting that imidazoline receptor activation is required for agmatine to enhance cannabinoid-evoked hypothermia. The present data reveal that agmatine and a cannabinoid agonist interact to produce a hypothermic synergy in rats. These results show that agmatine acts in the brain and via imidazoline receptors to enhance cannabinoid-evoked hypothermia.

  6. Protective Effect of Pretreatment with Acenocoumarol in Cerulein-Induced Acute Pancreatitis

    Science.gov (United States)

    Warzecha, Zygmunt; Sendur, Paweł; Ceranowicz, Piotr; Dembiński, Marcin; Cieszkowski, Jakub; Kuśnierz-Cabala, Beata; Olszanecki, Rafał; Tomaszewska, Romana; Ambroży, Tadeusz; Dembiński, Artur

    2016-01-01

    Coagulation is recognized as a key player in inflammatory and autoimmune diseases. The aim of the current research was to examine the effect of pretreatment with acenocoumarol on the development of acute pancreatitis (AP) evoked by cerulein. Methods: AP was induced in rats by cerulein administered intraperitoneally. Acenocoumarol (50, 100 or 150 µg/kg/dose/day) or saline were given once daily for seven days before AP induction. Results: In rats with AP, pretreatment with acenocoumarol administered at the dose of 50 or 100 µg/kg/dose/day improved pancreatic histology, reducing the degree of edema and inflammatory infiltration, and vacuolization of acinar cells. Moreover, pretreatment with acenocoumarol given at the dose of 50 or 100 µg/kg/dose/day reduced the AP-evoked increase in pancreatic weight, serum activity of amylase and lipase, and serum concentration of pro-inflammatory interleukin-1β, as well as ameliorated pancreatic DNA synthesis and pancreatic blood flow. In contrast, acenocoumarol given at the dose of 150 μg/kg/dose did not exhibit any protective effect against cerulein-induced pancreatitis. Conclusion: Low doses of acenocoumarol, given before induction of AP by cerulein, inhibit the development of that inflammation. PMID:27754317

  7. Protective Effect of Pretreatment with Acenocoumarol in Cerulein-Induced Acute Pancreatitis

    Directory of Open Access Journals (Sweden)

    Zygmunt Warzecha

    2016-10-01

    Full Text Available Coagulation is recognized as a key player in inflammatory and autoimmune diseases. The aim of the current research was to examine the effect of pretreatment with acenocoumarol on the development of acute pancreatitis (AP evoked by cerulein. Methods: AP was induced in rats by cerulein administered intraperitoneally. Acenocoumarol (50, 100 or 150 µg/kg/dose/day or saline were given once daily for seven days before AP induction. Results: In rats with AP, pretreatment with acenocoumarol administered at the dose of 50 or 100 µg/kg/dose/day improved pancreatic histology, reducing the degree of edema and inflammatory infiltration, and vacuolization of acinar cells. Moreover, pretreatment with acenocoumarol given at the dose of 50 or 100 µg/kg/dose/day reduced the AP-evoked increase in pancreatic weight, serum activity of amylase and lipase, and serum concentration of pro-inflammatory interleukin-1β, as well as ameliorated pancreatic DNA synthesis and pancreatic blood flow. In contrast, acenocoumarol given at the dose of 150 μg/kg/dose did not exhibit any protective effect against cerulein-induced pancreatitis. Conclusion: Low doses of acenocoumarol, given before induction of AP by cerulein, inhibit the development of that inflammation.

  8. Novel Route for Agmatine Catabolism in Aspergillus niger Involves 4-Guanidinobutyrase.

    Science.gov (United States)

    Kumar, Sunil; Saragadam, Tejaswani; Punekar, Narayan S

    2015-08-15

    Agmatine, a significant polyamine in bacteria and plants, mostly arises from the decarboxylation of arginine. The functional importance of agmatine in fungi is poorly understood. The metabolism of agmatine and related guanidinium group-containing compounds in Aspergillus niger was explored through growth, metabolite, and enzyme studies. The fungus was able to metabolize and grow on l-arginine, agmatine, or 4-guanidinobutyrate as the sole nitrogen source. Whereas arginase defined the only route for arginine catabolism, biochemical and bioinformatics approaches suggested the absence of arginine decarboxylase in A. niger. Efficient utilization by the parent strain and also by its arginase knockout implied an arginase-independent catabolic route for agmatine. Urea and 4-guanidinobutyrate were detected in the spent medium during growth on agmatine. The agmatine-grown A. niger mycelia contained significant levels of amine oxidase, 4-guanidinobutyraldehyde dehydrogenase, 4-guanidinobutyrase (GBase), and succinic semialdehyde dehydrogenase, but no agmatinase activity was detected. Taken together, the results support a novel route for agmatine utilization in A. niger. The catabolism of agmatine by way of 4-guanidinobutyrate to 4-aminobutyrate into the Krebs cycle is the first report of such a pathway in any organism. A. niger GBase peptide fragments were identified by tandem mass spectrometry analysis. The corresponding open reading frame from the A. niger NCIM 565 genome was located and cloned. Subsequent expression of GBase in both Escherichia coli and A. niger along with its disruption in A. niger functionally defined the GBase locus (gbu) in the A. niger genome.

  9. Protection effect of Emodin pretreatment on intestinal I - RI damage of intestinal mucosa in ratsa

    Institute of Scientific and Technical Information of China (English)

    Shu-Jie Zhao; Shi-Ji Wang; Hong-Xiang Li; Li-Hua Dong; Huai-Jiang He; Zhong-Min Liu; Yu-Shan Wang

    2014-01-01

    Objective:To tinvestigate the protective effect and mechanism of emodin pretreatment on intestinal mucosa of rats with intestinal ischemia-reperfusion injury.Methods:A total of50 SD rats were randomly divided into control group, model group, emodin groups of low, medium and high dose, with10 in each group.Ischemia-reperfusion injury(I-RI) mode was established by using noninvasive clamp on superior mesentericartery(SMA).Control group and model group were pretreated with0.5% sodium carboxymethyl cellulose solution lavage2 h before operation, emodin groups of low, medium and high dose were given emodin lavage with20,40,60 mg/kg pretreatment, femoral venous blood before the lavage pretreatment(T0) and1 h ischemia(T1) , and inferior vena venous blood after1 h of reperfusion(T2) were extracted from each group of rats for detection of serum level of intestinal fatty acid binding protein(I-FABP), tumor necrosis factor(TNF-α), endotoxin, interleukin6(IL-6), and the content of diamine oxidase(DAO);After model establishment, the rats were sacrificed, intestine homogenate was prepared by using blind intestinal tissue to detect intestinal tissue myeloperoxidase(MPO), malondialdehyde(MDA) and superoxide dismutase(SOD) levels.And upper small intestine tissue was retrieved, followed by fixation and conventionalHE staining to observe intestinal tissue morphology under light microscopy.Results:In emodin groups of low, medium and high dose atT1 andT2,I -FABP, TNF-α, endotoxin,IL-6 andDAO level were significantly lower than that of model group(P<0.05); in emodin group of low,medium and high dose,MPO andMDA content in intestinal tissue homogenate was significantly lower than that in model group(P<0.05),SOD level was significantly higher than that of model group(P<0.05).Intestinal damage of emodin low, medium and high dose groups were significantly lighter than model group.Conclusions:Emodin pretreatment has certain protective effect on intestinal mucosa in ischemia reperfusion injury.

  10. Systemic phosphatidylcholine pretreatment protects canine esophageal mucosa during acute experimental biliary reflux

    Institute of Scientific and Technical Information of China (English)

    Gabor Eros; Jozsef Kaszaki; Miklos Czobel; Mihaly Boros

    2006-01-01

    AIM: To characterize the consequences of short-term exposure to luminal bile on mucosal mast cell reactions in a canine model, and to determine the effects of systemic phosphatidylcholine pretreatment in this condition.METHODS: Twenty mongrel dogs were used for experiments. Group 1 (n = 5) served as a salinetreated control, while in group 2 (n=5) the esophagus was exposed to bile for 3 h. In group 3 (n=5) the animals were pretreated with 7-nitroindazole to inhibit the neuronal isoform of nitric oxide synthase.In group 4 (n = 5) phosphatidylcholine solution (50 mg/kg) was administered iv before the biliary challenge. Mucosal microcirculation was observed by intravital videomicroscopy. Myeloperoxidase and nitric oxide synthase activities, the degrees of mast cell degranulation and mucosal damage were evaluated via tissue biopsies.RESULTS: Exposure to bile evoked significant mast cell degranulation and leukocyte accumulation. The red blood cell velocity and the diameter of the postcapillary venules increased significantly. The tissue ATP content and constitutive nitric oxide synthase activity decreased,while the inducible nitric oxide synthase activity increased significantly as compared to the control values.7-nitroindazole treatment significantly exacerbated the mucosal mast cell degranulation and tissue damage. In contrast, phosphatidylcholine pretreatment prevented the bile-induced ATP depletion, the inducible nitric oxide synthase and myeloperoxidase activity and the mast cell degranulation increased.CONCLUSION: The neuronal nitric oxide synthase -mast cell axis plays an important role in the esophageal mucosal defense system. Systemic phosphatidylcholine pretreatment affords effective protection through ameliorating the bile-induced ATP depletion and secondary inflammatory reaction.

  11. 胍丁胺对脂多糖诱导急性肝损伤的保护作用%Protective effects of agmatine on lipopolysaccharide-induced acute hepatic injury in mice

    Institute of Scientific and Technical Information of China (English)

    李炫飞; 范霞; 郑志华; 杨雪; 刘政; 龚建平; 梁华平

    2013-01-01

    0.060 vs.0.853 ±0.080,t=5.849,P=0.004) in liver tissue.Histological examination demonstrated that AGM significantly reduced liver injury caused by LPS,as manifested in amelioration of hepatocytes swel1ling,necrosis and neutrophil infiltration.Conclusion Agmatine can reduce LPS-induced acute hepatic injury in mice via suppressing NF-κB translocation and reduction of the synthesis and release of cytokines.%目的 观察胍丁胺(AGM)对脂多糖(LPS)诱导急性肝损伤的保护作用,并探讨其作用机制.方法 将60只成年C57BL/6小鼠按随机数字表法分为对照组(20只,腹腔注射磷酸盐缓冲液10 mg/kg)、模型组(20只,腹腔注射LPS 10 mg/kg)和胍丁胺组(20只,腹腔注射LPS 10 mg/kg和胍丁胺200 mg/kg),各组于制模后6h和24h分别处死10只小鼠,采集血和肝组织制备组织匀浆.制模后6h采用酶联免疫吸附试验(ELISA)检测血清和肝组织中肿瘤坏死因子-α(TNF-α)、白细胞介素(IL-1β、IL-6)的含量;制模后24h用全自动生化分析仪测定血清丙氨酸转氨酶(ALT)、天冬氨酸转氨酶(AST)及总胆红素(TBil)水平;制模后6h采用蛋白质免疫印迹试验(Western blotting)检测肝细胞核内核转录因子-κB(NF-κB)p65的含量;制模后24h观察肝组织病理学改变.结果 制模后6h,模型组小鼠表现为精神萎靡、蜷缩少动、禁饮食水;胍丁胺组小鼠精神和活动明显好于模型组.胍丁胺治疗后能有效降低LPS所致急性肝损伤小鼠血清中TNF-α(μg/L:296.3±42.5比627.2±81.3,t=7.327,P=0.002)、IL-1β(μg/L:109.1±12.3比264.2±18.8,t=11.958,P=0.001)、IL-6(mg/L:11.4±1.9比23.6±2.5,t=6.729,P=0.003)、ALT(U/L:107.9±8.5比189.9±13.6,t=8.856,P=0.001)、AST(U/L:347.4±24.9比716.8±60.4,t=9.793,P=0.001)、TBil(μmol/L:8.3±0.9比10.6±0.5,t=3.869,P=0.018)的含量,减少肝组织TNF-α(ng/g:287.4±32.5比461.5±31.4,t=6.673,P=0.003)、IL-1β(pg/g:146.7±13.5比351.6±28.7,t=11.190,P=0.001)和核内NF-κB p65蛋白表达[NF-κB p65/

  12. Pretreatment of Ferulic Acid Protects Human Dermal Fibroblasts against Ultraviolet A Irradiation

    Science.gov (United States)

    Hahn, Hyung Jin; Kim, Ki Bbeum; Bae, Seunghee; Choi, Byung Gon; An, Sungkwan

    2016-01-01

    Background Approximately 90%~99% of ultraviolet A (UVA) ray reaches the Earth's surface. The deeply penetrating UVA rays induce the formation of reactive oxygen species (ROS), which results in oxidative stress such as photoproducts, senescence, and cell death. Thus, UVA is considered a primary factor that promotes skin aging. Objective Researchers investigated whether pretreatment with ferulic acid protects human dermal fibroblasts (HDFs) against UVA-induced cell damages. Methods HDF proliferation was analyzed using the water-soluble tetrazolium salt assay. Cell cycle distribution and intracellular ROS levels were assessed by flow cytometric analysis. Senescence was evaluated using a senescence-associated β-galactosidase assay, while Gadd45α promoter activity was analyzed through a luciferase assay. The expression levels of superoxide dismutase 1 (SOD1), catalase (CAT), xeroderma pigmentosum complementation group A and C, matrix metalloproteinase 1 and 3, as well as p21 and p16 were measured using quantitative real-time polymerase chain reaction. Results Inhibition of proliferation and cell cycle arrest were detected in cells that were irradiated with UVA only. Pretreatment with ferulic acid significantly increased the proliferation and cell cycle progression in HDFs. Moreover, ferulic acid pretreatment produced antioxidant effects such as reduced DCF intensity, and affected SOD1 and CAT mRNA expression. These effects were also demonstrated in the analysis of cell senescence, promoter activity, expression of senescent markers, and DNA repair. Conclusion These results demonstrate that ferulic acid exerts protective effects on UVA-induced cell damages via anti-oxidant and stress-inducible cellular mechanisms in HDFs. PMID:27904274

  13. Protective effects of erythropoietin pretreatment on myocardium with hypoxia/reoxygenation injury in rats

    Institute of Scientific and Technical Information of China (English)

    QIN Chuan; XIAO Ying-bin; ZHONG Qan-jin; CHEN Lin; WANG Xue-feng

    2004-01-01

    To establish the rat model with myocardial hypoxia/reoxygenation (H/R) injury, and investigatethe protective effect of EPO pretreatment on the myocardium. Methods: Sixty male adult Wistar rats were randomly divided in-to 3 groups: control group, H/R group, and EPO group, 20 in each group. The rats in EPO group accepted injection of 5 000U/kg recombinant human erythropoietin (RHuEPO) through vein, and the other rats accepted the injection of the same volumeof saline. Twenty-four hours after the injection, rats in the EPO and H/R groups were put into the hypoxia environment for 12h and then returned to the normoxic environment for 2 h, and then the samples of blood and myocardium were collected. Serummyocardial enzyme activity, apoptosis, ultrastructure, myocardial MDA contents, EPO receptor (EPOR) expression in cardiacmyocytes and cardiac functions were tested. Results: EPOR expression was positive in cardiac myocytes of adult rat according to the result of immunohistochemitry assaying. Compared to those in H/R group, rats in EPO group presented lighter injury ofmyocardial ultrastructure, the reduction of serum myocardial enzyme activity, inhibition of apoptosis, the better recovery ofcardiac functions, and the Ness production of oxygen-derived free radicals. Conclusion: Adult rat cardiac myocytes could ex-press EPOR, and EPO pretreatment produced protective effects on myocardium with H/R injury.

  14. A study of Corrosion Protection of Aluminum Metal by Tetraethoxysilane Plasma Polymerized Coatings-Influence of Aluminum Surface Pretreatments-

    Institute of Scientific and Technical Information of China (English)

    YoshihiroMomose; TatsuyaYabuki

    2004-01-01

    The corrosion-protective performance of plasma-polymerized (PP) coatings on pretreated aluminum substrates has been investigated by cathodic polarization curve measurement. The surface composition and electronic properties of the pretreated and PP film coated metal surfaces were also characterized by XPS and the temperature-programmed photoelectron emission (TPPE). A PP coating was prepared on the pretreated surfaces by plasma polymerization of a mixture of tetraethoxysilane (TEOS) monomer vapor and oxygen using a 13.56MHz radiofrequency generator. The polarization curve of PP film coated samples was measured in NaC1 aqueous solution. The weight loss rate calculated from the value of the corrosion current of the curve was used to estimate the protective performance of the PP film coated samples. Argon plasma treatment of the metal surface gave much better corrosion-protective performance than pretreatments such as oxidation by heating in air and diamond scratching. The XPS analysis indicated that the silicon oxide assigned to SiO2 was formed on the PP film coated surface. The TPPE analysis revealed that the electron emission characteristics for the metal surfaces pretreated only were strongly influenced by the pretreatments, while all the PP film coated samples exhibited nearly the same electron emission trend with a much decreased intensity.

  15. A study of Corrosion Protection of Aluminum Metal by Tetraethoxysilane Plasma Polymerized Coatings -Influence of Aluminum Surface Pretreatments-

    Institute of Scientific and Technical Information of China (English)

    Yoshihiro Momose; Tatsuya Yabuki

    2004-01-01

    The corrosion-protective performance of plasma-polymerized (PP) coatings on pretreated aluminum substrates has been investigated by cathodic polarization curve measurement. The surface composition and electronic properties of the pretreated and PP film coated metal surfaces were also characterized by XPS and the temperature-programmed photoelectron emission (TPPE). A PP coating was prepared on the pretreated surfaces by plasma polymerization of a mixture of tetraethoxysilane (TEOS) monomer vapor and oxygen using a 13.56MHz radiofrequency generator. The polarization curve of PP film coated samples was measured in NaCl aqueous solution. The weight loss rate calculated from the value of the corrosion current of the curve was used to estimate the protective performance of the PP film coated samples. Argon plasma treatment of the metal surface gave much better corrosion-protective performance than pretreatments such as oxidation by heating in air and diamond scratching. The XPS analysis indicated that the silicon oxide assigned to SiO2 was formed on the PP film coated surface. The TPPE analysis revealed that the electron emission characteristics for the metal surfaces pretreated only were strongly influenced by the pretreatments, while all the PP film coated samples exhibited nearly the same electron emission trend with a much decreased intensity.

  16. Transport of Diamines by Enterococcus faecalis Is Mediated by an Agmatine-Putrescine Antiporter

    NARCIS (Netherlands)

    Driessen, Arnold J.M.; Smid, Eddy J.; Konings, Wilhelmus

    1988-01-01

    Enterococcusfaecalis ATCC 11700 is able to use arginine and the diamine agmatine as a sole energy source. Via the highly homologous deiminase pathways, arginine and agmatine are converted into CO2, NH3, and the end products ornithine and putrescine, respectively. In the arginine deiminase pathway, u

  17. Pretreatment with Danhong injection protects the brain against ischemia-reperfusion injury.

    Science.gov (United States)

    Wang, Shaoxia; Guo, Hong; Wang, Xumei; Chai, Lijuan; Hu, Limin; Zhao, Tao; Zhao, Buchang; Tan, Xiaoxu; Jia, Feifei

    2014-08-01

    Danhong injection (DHI), a Chinese Materia Medica standardized product extracted from Radix Salviae miltiorrhizae and Flos Carthami tinctorii, is widely used in China for treating acute ischemic stroke. In the present study, we explored the neuroprotective efficacy of DHI in a rat model of temporary middle cerebral artery occlusion, and evaluated the potential mechanisms underlying its effects. Pretreatment with DHI (0.9 and 1.8 mL/kg) resulted in a significantly smaller infarct volume and better neurological scores than pretreatment with saline. Furthermore, DHI significantly reduced the permeability of the blood-brain barrier, increased occludin protein expression and decreased neutrophil infiltration, as well as profoundly suppressing the upregulation of matrix metallopeptidase-9 expression seen in rats that had received vehicle. Matrix metallopeptidase-2 expression was not affected by ischemia or DHI. Moreover, DHI (1.8 mL/kg) administered 3 hours after the onset of ischemia also improved neurological scores and reduced infarct size. Our results indicate that the neuroprotective efficacy of DHI in a rat model of cerebral ischemia-reperfusion injury is mediated by a protective effect on the blood-brain barrier and the reversal of neutrophil infiltration.

  18. The protective effect of erythropoietin pretreatment on ischemic acute renal failure in rats

    Directory of Open Access Journals (Sweden)

    Jing-Guang Liao

    2016-09-01

    Full Text Available Objective: To investigate the protective effect of erythropoietin (EPO pretreatment on ischemic acute renal failure in rats and its molecular mechanism. Methods: Male Sprague–Dawley rats were selected as experimental animals and they were randomly divided into the sham operation group (sham group, ischemia-reperfusion injury group (IRI group and EPO pretreatment group (EPO group. Each group had 15 rats. Serum specimens and renal specimens were collected after a IRI model was built for 4, 12 and 24 h. The contents of creatinine, urea nitrogen tumor necrosis factor-alpha (TNF-a, interleukin-1 (IL-1, IL-6 and IL-8 in serum and the contents of TNF-a, IL- 1, IL-6, IL-8, toll like receptor 4 (TLR4 and nuclear factor-kappa B (NF-kB in the kidney tissue were determined. Results: After 4, 12 and 24 h reperfusion, there were differences between the contents of creatinine, urea nitrogen TNF-a, IL-1, IL-6 and IL-8 in serum and the contents of TNF-a, IL-1, IL-6, IL-8, TLR4 and NF-kB in rats of the three groups (P < 0.05. The contents of creatinine, urea nitrogen TNF-a, IL-1, IL-6 and IL-8 in serum and the contents of TNF-a, IL-1, IL-6, IL-8, TLR4 and NF-kB in the kidney tissue in rats of the IRI group were significantly higher than those of the sham group; and the contents of creatinine, urea nitrogen TNF-a, IL-1, IL-6 and IL-8 in serum and the contents of TNF-a, IL-1, IL-6, IL- 8, TLR4 and NF-kB in the kidney tissue in rats of the EPO group were distinctly lower than those of the IRI group. Conclusions: EPO pretreatment can protect the renal function of rats with ischemic acute renal failure by inhibiting the TLR4/NF-kB pathway mediated inflammatory responses.

  19. Mediated protective effect of electroacupuncture pretreatment by miR-214 on myocardial ischemia/reperfusion injury

    Institute of Scientific and Technical Information of China (English)

    Pei-Yu LIU; Yi TIAN; Shi-Yuan XU

    2014-01-01

    Background Electroacupuncture pretreatment plays a protective role in myocardial ischemia/reperfusion (I/R) injury and microRNAs (miRNAs) could act on various facets of cardiac function. However, the role of miRNAs in the cardioprotection by electroacupuncture pre-treatment on myocardial I/R injury remains unknown. The purpose of the study was to examine whether miR-214 was involved in cardio-protection by electroacupuncture. Methods Using rat myocardial I/R model, we examined the role of electroacupuncture pretreatment in myocardial I/R injury and analyzed the changes in the expression of miR-214. In addition, I/R was simulated in vitro by performing oxy-gen-glucose deprivation (OGD) on H9c2 cell cultures, and the effect of electroacupuncture pretreatment on I/R injury as well as expressional level of miR-214 were examined in vitro. Furthermore, the miR-214 mimic was transfected into OGD-treated H9c2 cells, we analyzed the cell apoptosis, lactate dehydrogenase (LDH) and creatine kinase (CK) activities, intracellular free Ca2+concentration ([Ca2+]i) as well as the relative protein levels of sodium/calcium exchanger 1(NCX1), BCL2-like 11 (BIM), calmodulin-dependent protein kinase IIδ(CaMKIIδ) and Cyclophilin D (CypD). Results The in vivo results revealed that compared with the I/R group, the electroacupuncture pretreatment group showed significant decreased myocardial infarct size, as well as the increased indices of the cardiac function, including heart rate, mean arterial pressure, left ventricular systolic pressure and maximal rate for left ventricular pressure rising and declining (±dp/dt max). In addition, electroacupuncture pretreatment could inhibit the elevation of LDH and CK activities induced by I/R injury. The quantitative PCR (qPCR) results demonstrated electroacupuncture pretreatment could provide cardioprotection against myocardial I/R injury in rats with miR-214 up-regulation. In the meanwhile, in vitro, electroacupuncture pretreatment protected H9

  20. The Protective Effects of Sufentanil Pretreatment on Rat Brains under the State of Cardiopulmonary Bypass.

    Science.gov (United States)

    Zhang, Kun; Li, Man; Peng, Xiao-Chun; Wang, Li-Shen; Dong, Ai-Ping; Shen, Shu-Wei; Wang, Rong

    2015-01-01

    This study aimed to observe the protective effects of sufentanil pretreatment on rat cerebral injury during cardiopulmonary bypass (CPB) and to explore the underlying mechanism. Twenty-four male adult Sprague Dawley (SD) rats were divided into 4 groups. Then, the rat CPB model was established. A 14G trocar was inserted into the atrium dextrum. For rats in S1 and S5 groups, sufentanil (1 µgKg(-1) and 5 µgKg(-1)) were applied before CPB process. After the operation, rat brain samples were harvested for measurement of the water content of the brains, total calcium in brain tissue and the level of serum S100β. Compared with the Sham group, the water content and the total calcium of the brain tissue, and the expression of S100β in serum were significantly increased in the CPB group (PCPB group, sufentanil treatment significantly reduced the water content of the brains, the total calcium and S100β expression (PCPB, S1, and S5 compared with Sham group during CPB. Compared with the Sham group, the levels of pH and blood lactate in other groups were decreased and increased, respectively, in the post-CPB period. During the CPB and post-CPB periods, the hematocrit levels were significantly down-regulated in groups CPB, S1, and S5 compared with Sham group. In conclusion, sufentanil pretreatment was effective in reducing the cerebral injury during CPB. Reduction in calcium overload may be a potential mechanism in such process.

  1. Protective effects of pretreatment with Radix Paeoniae Rubra on acute lung injury induced by intestinal ischemia/ reperfusion in rats

    Institute of Scientific and Technical Information of China (English)

    CHEN Chang; ZHANG Fan; XIA Zhong-yuan; LIN Hui; MO An-sheng

    2008-01-01

    Objective: To investigate the effect of pretreatment with Radix Paeoniae Rubra (RPR) on acute lung injury induced by intestinal ischemia/reperfusion in rats and its protective mechanism.Methods:n lung tissues was detected by immunohistochemistry and morphometry computer image analysis. Arterial blood gas analysis, lung permeability index, malondialdehyde (MDA) and superoxide dismutase (SOD) contents in lungs were measured. The histological changes of lung tissue were observed under light microscope.Results:The expression of HO-1 in RPR-pretreatment group and hemin group was obviously higher than that in sham-operation group and I/R group (P < 0.01). The level of MDA and lung permeability index in RPR-pretreatment and hemin group were significantly lower than those in I/R group (P<0.01 or P<0.05), while the activity of SOD in RPR-pretreatment and hemin group was obviously higher than that in I/R group (P<0.01 ). Under light microscope, the pathologic changes induced by I/R were significantly attenuated by RPR.Conclusion : Intestinal ischemia/reperfusion may result in acute lung injury and pretreatment with RPR injection can attenuate the injury. The protective effect of RPR on the acute lung injury is related to its property of inducing HO-1 expression and inhibiting lipid peroxidation.

  2. Mechanism underlying blockade of voltage-gated calcium channels by agmatine in cultured rat hippocampal neurons

    Institute of Scientific and Technical Information of China (English)

    Jian-quan ZHENG; Xie-chuan WENG; Xiao-dan GAI; Jin LI; Wen-bin XIAO

    2004-01-01

    AIM: To investigate whether agmatine could selectively block a given type of the voltage-gated calcium channels (VGCC) and whether related receptors are involved in the blocking effect of agmatine on VGCC. METHODS: The whole-cell patch recording technique was performed to record VGCC currents in the cultured neonatal rat hippocampal neurons. RESULTS: Verapamil (100 μmol/L), a selective blocker of L-type calcium channel, significantly inhibited VGCC current by 80 %± 7 %. Agmatine (100 μmol/L) could further depress the remained currents by 25 %±6 %. The α2-adrenoceptor antagonist yohimbine (10 μmol/L) and the I2 imidazoline receptor antagonist idazoxon (10 and 40 μmol/L) had no significant effect on VGCC currents when used respectively. When the mixture of yohimbine and agmatine was applied, VGCC currents were still depressed remarkably. However, the blocking effect of agmatine was decreased by 29 %± 8 % in the presence of idazoxon (10 μmol/L). The effect of idazoxon did not increase at a higher concentration (40 μmol/L). CONCLUSION: Agmatine could block the L- and other types of VGCC currents in the cultured rat hippocampal neurons. Blocking effect of agmatine on VGCC was partially related to I2 imidazoline receptor and had no relationship with α2-adrenoceptors.

  3. Discovery of an operon that participates in agmatine metabolism and regulates biofilm formation in Pseudomonas aeruginosa.

    Science.gov (United States)

    Williams, Bryan J; Du, Rui-Hong; Calcutt, M Wade; Abdolrasulnia, Rasul; Christman, Brian W; Blackwell, Timothy S

    2010-04-01

    Agmatine is the decarboxylation product of arginine and a number of bacteria have devoted enzymatic pathways for its metabolism. Pseudomonas aeruginosa harbours the aguBA operon that metabolizes agmatine to putrescine, which can be subsequently converted into other polyamines or shunted into the TCA cycle for energy production. We discovered an alternate agmatine operon in the P. aeruginosa strain PA14 named agu2ABCA' that contains two genes for agmatine deiminases (agu2A and agu2A'). This operon was found to be present in 25% of clinical P. aeruginosa isolates. Agu2A' contains a twin-arginine translocation signal at its N-terminus and site-directed mutagenesis and cell fractionation experiments confirmed this protein is secreted to the periplasm. Analysis of the agu2ABCA' promoter demonstrates that agmatine induces expression of the operon during the stationary phase of growth and during biofilm growth and agu2ABCA' provides only weak complementation of aguBA, which is induced during log phase. Biofilm assays of mutants of all three agmatine deiminase genes in PA14 revealed that deletion of agu2ABCA', specifically its secreted product Agu2A', reduces biofilm production of PA14 following addition of exogenous agmatine. Together, these findings reveal a novel role for the agu2ABCA' operon in the biofilm development of P. aeruginosa.

  4. Transcriptome profiling of Lactococcus lactis subsp. cremoris CECT 8666 in response to agmatine

    Directory of Open Access Journals (Sweden)

    Beatriz del Rio

    2016-03-01

    Full Text Available The dairy strain Lactococcus lactis subsp. cremoris CECT 8666 (formerly GE2-14 synthesizes the biogenic amine putrescine from agmatine via the agmatine deiminase (AGDI pathway [1]. The AGDI cluster of L. lactis is composed by five genes aguR, aguB, aguD, aguA and aguC. The last four genes are co-transcribed as a single policistronic mRNA forming the catabolic operon aguBDAC, which encodes the proteins necessary for agmatine uptake and its conversion into putrescine [1,2]. The first gene of the cluster, aguR, encodes a transmembrane protein that functions as a one-component signal transduction system that senses the agmatine concentration of the medium and accordingly regulates the transcription of aguBDAC [2]. The catabolic operon aguBDAC is transcriptionally activated by agmatine [2] and transcriptionally regulated by carbon catabolite repression (CCR via glucose, but not by other sugars such as lactose or galactose [1,3]. On the contrary, the transcription of the aguR regulatory gene is not subject to CCR regulation [1,3] nor is regulated by agmatine [2]. In this study we report the transcriptional profiling of L. lactis subsp. cremoris CECT 8666 grown in M17 medium with galactose (GalM17 as carbon source and supplemented with agmatine, compared to that of the strain grown in the same culture medium without agmatine. The transcriptional profiling data of agmatine-regulated genes were deposited in the Gene Expression Omnibus (GEO database under Accession no. GSE74808.

  5. Transcriptome profiling of Lactococcus lactis subsp. cremoris CECT 8666 in response to agmatine.

    Science.gov (United States)

    Del Rio, Beatriz; Redruello, Begoña; Martin, M Cruz; Fernandez, Maria; de Jong, Anne; Kuipers, Oscar P; Ladero, Victor; Alvarez, Miguel A

    2016-03-01

    The dairy strain Lactococcus lactis subsp. cremoris CECT 8666 (formerly GE2-14) synthesizes the biogenic amine putrescine from agmatine via the agmatine deiminase (AGDI) pathway [1]. The AGDI cluster of L. lactis is composed by five genes aguR, aguB, aguD, aguA and aguC. The last four genes are co-transcribed as a single policistronic mRNA forming the catabolic operon aguBDAC, which encodes the proteins necessary for agmatine uptake and its conversion into putrescine [1], [2]. The first gene of the cluster, aguR, encodes a transmembrane protein that functions as a one-component signal transduction system that senses the agmatine concentration of the medium and accordingly regulates the transcription of aguBDAC[2]. The catabolic operon aguBDAC is transcriptionally activated by agmatine [2] and transcriptionally regulated by carbon catabolite repression (CCR) via glucose, but not by other sugars such as lactose or galactose [1], [3]. On the contrary, the transcription of the aguR regulatory gene is not subject to CCR regulation [1], [3] nor is regulated by agmatine [2]. In this study we report the transcriptional profiling of L. lactis subsp. cremoris CECT 8666 grown in M17 medium with galactose (GalM17) as carbon source and supplemented with agmatine, compared to that of the strain grown in the same culture medium without agmatine. The transcriptional profiling data of agmatine-regulated genes were deposited in the Gene Expression Omnibus (GEO) database under Accession no. GSE74808.

  6. Protective effect and mechanism of lithium chloride pretreatment on myocardial ischemia-reperfusion injury in rats

    Institute of Scientific and Technical Information of China (English)

    Fang-Jiang Li; Tao Hsu; Hui-Xian Li; Jin-Zheng Shi; Mei-Ling Du; Xiao-Yuan Wang; Wen-Ting Zhang

    2014-01-01

    Objective:To investigate the protective effect and mechanism of lithium chloride pretreatment on myocardial ischemia-reperfusion injury(I-RI) in rats.Methods:A total of60SD rats were randomly divided into control group, model group, lithium chloride intervention group and L-arginine methyl ester+ lithium chloride intervention group with15 in each.TheI-RI model was established in model group, the lithium chloride intervention group andL-arginine methyl ester+ lithium chloride intervention group by method of seaming along left anterior descending coronary artery myocardial, control group was only opened the chest without seaming,ST-elevation within2 min was regarded as modeling success.Model group did not adopted any intervention, lithium chloride intervention group was treated with lithium chloride injection 15 mg/kg by jugular venipuncture preoperatively,L-arginine methyl ester+ lithium chloride intervention group was treated with intraperitoneal injection of30 mg•kg-1•d-1L-arginine methyl ester7 d before the test, and intravenous catheter of15 mg/kg lithium chloride preoperatively. The hydroxybutyric acid dehydrogenase(HBDH), creatine kinase isoenzyme(CK-MB), superoxide dismutase(SOD), malondialdehyde(MDA) level and nitric oxide synthase(NOS) activites were tested.Each large area of myocardial ischemia tissue was extracted for determination of the MDA content,SOD activity in tissue and serum, and morphological changes of myocardial tissue.Results:SOD activity was highest in lithium chloride intervention group, followed by L-arginine methyl ester+ lithium chloride intervention group, control group and model group (P0.05);HBDH andCK-MB of plasma were highest in model group, followed byL-arginine methyl ester+ lithium chloride intervention group, lithium chloride intervention group and control group(P<0.05).A significantly lighter myocardial damage was observed microscopically in lithium chloride intervention group than that inL-arginine methyl ester+ lithium

  7. Structure and stability of complexes of agmatine with some functional receptor residues of proteins

    Science.gov (United States)

    Remko, Milan; Broer, Ria; Remková, Anna; Van Duijnen, Piet Th.

    2017-04-01

    The paper reports the results of a theoretical study of the conformational behavior and basicity of biogenic amine agmatine. The complexes modelling of agmatine - protein interaction are also under scrutiny of our investigation using the Becke3LYP and B97D levels of the density functional theory. The relative stabilities (Gibbs energies) of individual complexes are by both DFT methods described equally. Hydration has a dramatic effect on the hydrogen bonded complexes studied. The pairing acidic carboxylate group with different agmatine species resulted in charged hydrogen bond complexes containing negatively charged acetate species acting as proton acceptors.

  8. Protective effects of hemin pretreatment combined with ulinastatin on septic shock in rats

    Institute of Scientific and Technical Information of China (English)

    YU Jian-bo; YAO Shang-long

    2008-01-01

    Background Urinary trypsin Inhibitor inhibits the enhanced production of pro-inflammatory molecules. Hemeoxygenase-1 induction protects against ischemia/reperfusion injury, oxidative stress, inflammation, transplant rejection, apoptosis, and other conditions. However, it is unknown if a combined hemin and ulinastatin pretreatment could result in protective effects for septic shock. In this study, we investigated the role of hemin pretreatment combined with ulinastatin on septic shock in rats.Methods Eighty healthy, male Sprague-Dawley rats were randomly divided into four groups: group S, group H, group U and group HU. Groups S and U received 1 ml normal saline intraperitoneally, while groups H and HU both received 1 ml (100 mg /kg) hemin. Twenty-four hours later, 0.5 ml (10 mg/kg) E. Coli lipopolysaccharide was injected intravenously to replicate the experimental model of septic shock. After an initial 25% decrease in the mean arterial pressure, corresponding to time point 0, groups HU and U received 0.5 ml 10 000 U/kg ulinastatin intravenously, and the others received 0.5 ml normal saline.Results The number of deaths in groups H and U was Iower than that in the group S (P<0.05), and was higher than that in group HU (all P<0.05) respectively. The mean arterial pressure (MAP) in the group S was significantly greater than that in group H (P<0.05), and was Iower than that in group HU and group U (P<0.05). The plasma levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), creatinine (Cr) and blood urea nitrogen (BUN), the malondial-dehyde (MDA) of liver, kidney and lung, and the lung Evans blue (EB) Contents in groups H and U, were greater than that in group HU (all P<0.05), and were Iower than that in group S (all P<0.05). In contrast, the plasma levels of CO in groups H and HU were higher than that in groups S and U (all P<0.05), and SOD of liver, kidney and lung in groups H and U were higher than that in group S, and were Iower than

  9. Pretreatment with scutellaria baicalensis stem-leaf total lfavonoid protects against cerebral ischemia/reperfusion injur y in hippocampal neurons

    Institute of Scientific and Technical Information of China (English)

    Xiangyu Kong; Wei Kong; Guangxin Miao; Shumin Zhao; Meng Chen; Xiaoying Zheng; Jiangtao Bai

    2014-01-01

    Previous experimental studies have shown that cerebral infarction can be effectively reduced following treatment with scutellaria baicalensis stem-leaf total lfavonoid (SSTF). However, the mechanism of action of SSTF as a preventive drug to treat cerebral infarction remains unclear. In this study, Sprague-Dawley rats were pretreated with 50, 100, 200 mg/kg SSTF via intragastric ad-ministration for 1 week prior to the establishment of focal cerebral ischemia/reperfusion injury. The results showed that pretreatment with SSTF effectively improved neurological function, re-duced brain water content and the permeability of blood vessels, ameliorated ischemia-induced morphology changes in hippocampal microvessels, down-regulated Fas and FasL protein expres-sion, elevated the activity of superoxide dismutase and glutathione peroxidase, and decreased malondialdehyde content. In contrast to low-dose SSTF pretreatment, the above changes were most obvious after pretreatment with moderate-and high-doses of SSTF. Experimental ifndings indicate that SSTF pretreatment can exert protective effects on the brain against cerebral isch-emia/reperfusion injury. The underlying mechanisms may involve reducing brain water content, increasing microvascular recanalization, inhibiting the apoptosis of hippocampal neurons, and attenuating free radical damage.

  10. Inhibitory effect of agmatine on proliferation of tumor cells by modulation of polyamine metabolism

    Institute of Scientific and Technical Information of China (English)

    Ji-fang WANG; Rui-bin SU; Ning WU; Bo XU; Xin-qiang LU; Yin LIU; Jin LI

    2005-01-01

    Aim: To assess the inhibitory effect of agmatine on tumor growth in vivo and tumor cell proliferation in vitro. Methods: The transplanted animal model,[3H]thymidine incorporation assay, 3- [4,5-dimethythiazol-2-yl]-2,5-diphenyltetrazo lium assay, and lactate dehydrogenase (LDH) release assay were performed.Results: Agmatine, at doses of 5-40 mg/kg, suppressed the S180 sarcoma tumor growth dose-dependently in mice in vivo and the highest inhibitory ratio reached 31.3% in Kunming mice and 50.0% in Balb/c mice, respectively. Similar results were obtained in the transplanted B16 melanoma tumor model. Agmatine (1-1000 μmol/L) was able to attenuate the proliferation of cultured MCF-7 human breast cancer cells in vitro in a concentration-dependent manner and the highest inhibitory ratio reached 50.3% in the [3H]thymidine incorporation assay.Additionally, in the LDH release assay, spermine (20 μmol/L) and spermidine (20 μmol/L) increased the LDH release significantly, but agmatine (1-1000 μmol/L) did not, indicating that the inhibitory effect of agmatine on the proliferation of MCF was not related to cellular toxicity. In the [3H]thymidine incorporation assay,putrescine (12.5-100.0 μmol/L) could reverse the inhibitory effect of agmatine on the proliferation of MCF concentration-dependently, suggesting that the inhibitory effect of agmatine on the proliferation of MCF might be associated with a decreased level of the intracellular polyamines pool. Conclusion: Agmatine had significant inhibitory effect on transplanted tumor growth in vivo and proliferation of tumor cells in vitro, and the mechanism might be a result of inducing decrease of intracellular polyamine contents.

  11. Antioxidative Peptides Derived from Enzyme Hydrolysis of Bone Collagen after Microwave Assisted Acid Pre-Treatment and Nitrogen Protection

    Directory of Open Access Journals (Sweden)

    Jin Sun

    2010-11-01

    Full Text Available This study focused on the preparation method of antioxidant peptides by enzymatic hydrolysis of bone collagen after microwave assisted acid pre-treatment and nitrogen protection. Phosphoric acid showed the highest ability of hydrolysis among the four other acids tested (hydrochloric acid, sulfuric acid and/or citric acid. The highest degree of hydrolysis (DH was 9.5% using 4 mol/L phosphoric acid with a ratio of 1:6 under a microwave intensity of 510 W for 240 s. Neutral proteinase gave higher DH among the four protease tested (Acid protease, neutral protease, Alcalase and papain, with an optimum condition of: (1 ratio of enzyme and substrate, 4760 U/g; (2 concentration of substrate, 4%; (3 reaction temperature, 55 °C and (4 pH 7.0. At 4 h, DH increased significantly (P < 0.01 under nitrogen protection compared with normal microwave assisted acid pre-treatment hydrolysis conditions. The antioxidant ability of the hydrolysate increased and reached its maximum value at 3 h; however DH decreased dramatically after 3 h. Microwave assisted acid pre-treatment and nitrogen protection could be a quick preparatory method for hydrolyzing bone collagen.

  12. 区域性血管床对局部注射胍丁胺的不同反应%Differential responses of regional vascular beds to local injection of agmatine in rats

    Institute of Scientific and Technical Information of China (English)

    李清; 范振中; 王义和; 何瑞荣

    2001-01-01

    在66只麻醉大鼠, 分别采用后肢、肾脏和肠系膜动脉在体恒流灌注法, 观察了向灌流环路中直接注射胍丁胺 (agmatine, AGM)的血管效应, 以所引起的灌流压增减反映血管的收缩和舒张.所得结果如下: (1) 不同剂量的AGM (0.1、 0.5、 1 mg/kg)注射于股部灌注环路时, 可剂量依赖性地增高后肢血管的灌流压.无论预先注射咪唑啉受体(imidazoline receptor, IR)和α2-肾上腺素能受体阻断剂 (α2-adrenergic receptor, α2-AR) idazoxan (0.5 mg/kg)或注射α2-肾上腺素能受体阻断剂yohimbine (1 mg/kg)均可完全阻抑上述AGM的效应. (2)向肾血管灌注环路中直接注射AGM也可剂量依赖性地增高肾血管的灌流压, 需特别指出的是: 大剂量AGM (1 mg/mg)引起肾血管双相的灌流压增高, 此效应可被idazoxan 完全阻断.而在预先应用yohimbine后, 再注射AGM则引起肾血管灌流压降低.(3)在肠系膜血管灌流环路中注射AGM可剂量依赖性地降低其灌流压.此效应可被idazoxan (0.5 mg/kg)完全阻断, 而yohimbine (1 mg/kg)对此无作用.根据上述结果得出的结论是, AGM对后肢、肾脏和肠系膜血管床的血管紧张性具有不同的作用.%In 66 anaesthetized rats, the effects of local injection of agmatine on femoral, renal, and mesenteric vascular beds were investigated respectively by constant flow perfusion method. The results are as follows. (1) Agmatine (0.1, 0.5, 1 mg/kg) increased the perfusion pressure (PP) of femoral vascular bed in a dose-dependent manner. The effect of agmatine (1 mg/kg) was completely blocked by pretreatment with idazoxan (0.5 mg/kg), an antagonist for imidazoline receptors (IR) and α2-adrenergic receptors (α2-AR), and yohimbine (1 mg/kg), a selective α2-AR antagonist. (2) Agmatine also increased the PP of renal vascular bed in a dose-dependent manner, and agmatine at high dose (1 mg/kg) caused a biphasic increase of PP in renal vascular bed. Idazoxan blocked these

  13. Effect of agmatine on experimental vascular endothelial dysfunction.

    Science.gov (United States)

    Nader, M A; Gamiel, N M; El-Kashef, H; Zaghloul, M S

    2016-05-01

    This study was designed to investigate the effect of agmatine sulfate (AG, CAS2482-00-0) in nicotine (NIC)-induced vascular endothelial dysfunction (VED) in rabbits. NIC was administered to produce VED in rabbits with or without AG for 6 weeks. Serum lipid profile, serum thiobarbituric acid reactive substances, reduced glutathione, superoxide dismutase generation, serum nitrite/nitrate, serum vascular cellular adhesion molecule-1 (VCAM-1), and aortic nuclear factor κB (NF-κB) levels were analyzed.Treatment with AG markedly improves lipid profile and prevented NIC-induced VED and oxidative stress. The mechanism of AG in improving NIC-induced VED may be due to the significant reduction in serum VCAM-1 levels and aortic NF-κB. Thus, it may be concluded that AG reduces the oxidative stress, nitric oxide production, VCAM-1 levels, and aortic NF-κB expression, thereby consequently improving the integrity of vascular endothelium.

  14. Agmatine suppresses peripheral sympathetic tone by inhibiting N-type Ca(2+) channel activity via imidazoline I2 receptor activation.

    Science.gov (United States)

    Kim, Young-Hwan; Jeong, Ji-Hyun; Ahn, Duck-Sun; Chung, Seungsoo

    2016-08-26

    Agmatine, a putative endogenous ligand of imidazoline receptors, suppresses cardiovascular function by inhibiting peripheral sympathetic tone. However, the molecular identity of imidazoline receptor subtypes and its cellular mechanism underlying the agmatine-induced sympathetic suppression remains unknown. Meanwhile, N-type Ca(2+) channels are important for the regulation of NA release in the peripheral sympathetic nervous system. Therefore, it is possible that agmatine suppresses NA release in peripheral sympathetic nerve terminals by inhibiting Ca(2+) influx through N-type Ca(2+) channels. We tested this hypothesis by investigating agmatine effect on electrical field stimulation (EFS)-evoked contraction and NA release in endothelium-denuded rat superior mesenteric arterial strips. We also investigated the effect of agmatine on the N-type Ca(2+) current in superior cervical ganglion (SCG) neurons in rats. Our study demonstrates that agmatine suppresses peripheral sympathetic outflow via the imidazoline I2 receptor in rat mesenteric arteries. In addition, the agmatine-induced suppression of peripheral vascular sympathetic tone is mediated by modulating voltage-dependent N-type Ca(2+) channels in sympathetic nerve terminals. These results suggest a potential cellular mechanism for the agmatine-induced suppression of peripheral sympathetic tone. Furthermore, they provide basic and theoretical information regarding the development of new agents to treat hypertension.

  15. Role of NF-κB in protection of EPO pretreatment on neonatal rat cardiac myocytes with hypoxia/reoxygenation injury

    Institute of Scientific and Technical Information of China (English)

    QIN Chuan; XIAO Ying-bin; ZHONG Qian-jin; CHEN Lin; WANG Xue-feng

    2005-01-01

    Objective:To observe the protective effects of erythropoietin (EPO) pretreatment on cardiac myocyte with hypoxia/reoxygenation (H/R) injury and the role of NF-κB in this effects. Methods:After the H/R model of cardiac myocytes of neonatal rats was established, the cultured cardiac myocytes were divided into 4 groups, including EPO pretreatment group ( EPO 10 U/ml 24 h before H/R), EPO pretreatment + PDTC group( EPO 10 U/ml and PDTC 5 μg/ml 24 h before H/R), PDTC group (PDTC 5 μg /ml 24 h before H/R) and control group. Before and after the H/R, assay of LDH concentration in the culture medium, the survival rate of the myocytes tested by MTT chromatometry and the apoptosis by flow cytometry were undertaken. Activation of NF-κB was determined by EMSA before and after H/R. Results:EPO pretreatment markedly reduced the LDH concentration in the medium, elevated the survival rate of myocytes and inhibited the apoptosis after H/R. Addition of PDTC during the pretreatment abolished the protective effects of EPO pretreatment. NF-κB was markedly activated during EPO pretreatment and PDTC inhibited the activation. However, after H/R, the activity of NF-κB in myocytes with EPO pretreatment was significantly inhibited compared to the other myocytes. Conclusion:NF-κB is significantly activated during EPO pretreatment, but is inhibited after H/R, which is correlated with the protective effects of EPO pretreatment on cardiac myocytes with H/R. This phenomenon can be explained as the negative feedback mechanism of the activation of NF-κB.

  16. Chronic treatment with glucocorticoids alters rat hippocampal and prefrontal cortical morphology in parallel with endogenous agmatine and arginine decarboxylase levels.

    Science.gov (United States)

    Zhu, Meng-Yang; Wang, Wei-Ping; Huang, Jingjing; Regunathan, Soundar

    2007-12-01

    In the present study, we examined the possible effect of chronic treatment with glucocorticoids on the morphology of the rat brain and levels of endogenous agmatine and arginine decarboxylase (ADC) protein, the enzyme essential for agmatine synthesis. Seven-day treatment with dexamethasone, at a dose (10 and 50 mug/kg/day) associated to stress effects contributed by glucocorticoids, did not result in obvious morphologic changes in the medial prefrontal cortex and hippocampus, as measured by immunocytochemical staining with beta-tubulin III. However, 21-day treatment (50 mug/kg/day) produced noticeable structural changes such as the diminution and disarrangement of dendrites and neurons in these areas. Simultaneous treatment with agmatine (50 mg/kg/day) prevented these morphological changes. Further measurement with HPLC showed that endogenous agmatine levels in the prefrontal cortex and hippocampus were significantly increased after 7-day treatments with dexamethasone in a dose-dependent manner. On the contrary, 21-day treatment with glucocorticoids robustly reduced agmatine levels in these regions. The treatment-caused biphasic alterations of endogenous agmatine levels were also seen in the striatum and hypothalamus. Interestingly, treatment with glucocorticoids resulted in a similar change of ADC protein levels in most brain areas to endogenous agmatine levels: an increase after 7-day treatment versus a reduction after 21-day treatment. These results demonstrated that agmatine has neuroprotective effects against structural alterations caused by glucocorticoids in vivo. The parallel alterations in the endogenous agmatine levels and ADC expression in the brain after treatment with glucocorticoids indicate the possible regulatory effect of these stress hormones on the synthesis and metabolism of agmatine in vivo.

  17. Adolescent pre-treatment with oxytocin protects against adult methamphetamine-seeking behavior in female rats.

    Science.gov (United States)

    Hicks, Callum; Cornish, Jennifer L; Baracz, Sarah J; Suraev, Anastasia; McGregor, Iain S

    2016-03-01

    The neuropeptide oxytocin (OT), given acutely, reduces self-administration of the psychostimulant drug methamphetamine (METH). Additionally, chronic OT administration to adolescent rats reduces levels of alcohol consumption in adulthood, suggesting developmental neuroplasticity in the OT system relevant to addiction-related behaviors. Here, we examined whether OT exposure during adolescence might subsequently inhibit METH self-administration in adulthood. Female Sprague-Dawley rats were administered vehicle or OT (1 mg/kg, i.p.) once daily from postnatal days (PND) 28 to 37 (adolescence). At PND 62 (adulthood), rats were trained to self-administer METH (intravenous, i.v.) in daily 2-hour sessions for 10 days under a fixed ratio 1 (FR1) reinforcement schedule, followed by determination of dose-response functions (0.01-0.3 mg/kg/infusion, i.v.) under both FR1 and progressive ratio (PR) schedules of reinforcement. Responding was then extinguished, and relapse to METH-seeking behavior assessed following priming doses of non-contingent METH (0.1-1 mg/kg, i.p.). Finally, plasma was collected to determine pre-treatment effects on OT and corticosterone levels. Results showed that OT pre-treatment did not significantly inhibit the acquisition of METH self-administration or FR1 responding. However, rats pre-treated with OT responded significantly less for METH under a PR reinforcement schedule, and showed reduced METH-primed reinstatement with the 1 mg/kg prime. Plasma OT levels were also significantly higher in OT pre-treated rats. These results confirm earlier observations that adolescent OT exposure can subtly, yet significantly, inhibit addiction-relevant behaviors in adulthood.

  18. Agmatine induced NO dependent rat mesenteric artery relaxation and its impairment in salt-sensitive hypertension.

    Science.gov (United States)

    Gadkari, Tushar V; Cortes, Natalie; Madrasi, Kumpal; Tsoukias, Nikolaos M; Joshi, Mahesh S

    2013-11-30

    l-Arginine and its decarboxylated product, agmatine are important mediators of NO production and vascular relaxation. However, the underlying mechanisms of their action are not understood. We have investigated the role of arginine and agmatine in resistance vessel relaxation of Sprague-Dawley (SD) and Dahl salt-sensitive hypertensive rats. Second or 3rd-order mesenteric arterioles were cannulated in an organ chamber, pressurized and equilibrated before perfusing intraluminally with agonists. The vessel diameters were measured after mounting on the stage of a microscope fitted with a video camera. The gene expression in Dahl rat vessel homogenates was ascertained by real-time PCR. l-Arginine initiated relaxations (EC50, 5.8±0.7mM; n=9) were inhibited by arginine decarboxylase (ADC) inhibitor, difluoromethylarginine (DFMA) (EC50, 18.3±1.3mM; n=5) suggesting that arginine-induced vessel relaxation was mediated by agmatine formation. Agmatine relaxed the SD rat vessels at significantly lower concentrations (EC50, 138.7±12.1μM; n=22), which was compromised by l-NAME (l-N(G)-nitroarginine methyl ester, an eNOS inhibitor), RX821002 (α-2 AR antagonist) and pertussis toxin (G-protein inhibitor). The agmatine-mediated vessel relaxation from high salt Dahl rats was abolished as compared to that from normal salt rats (EC50, 143.9±23.4μM; n=5). The α-2A AR, α-2B AR and eNOS mRNA expression was downregulated in mesenteric arterioles of high-salt treated Dahl hypertensive rats. These findings demonstrate that agmatine facilitated the relaxation via activation of α-2 adrenergic G-protein coupled receptor and NO synthesis, and this pathway is compromised in salt-sensitive hypertension.

  19. Agmatine increases proliferation of cultured hippocampal progenitor cells and hippocampal neurogenesis in chronically stressed mice

    Institute of Scientific and Technical Information of China (English)

    Yun-feng LI; Hong-xia CHEN; Ying LIU; You-zhi ZHANG; Yan-qin LIU; Jin LI

    2006-01-01

    Aim:To explore the mechanism of agmatine's antidepressant action.Methods: Male mice were subjected to a variety of unpredictable stressors on a daily basis over a 24-d period.The open-field behaviors of the mice were displayed and recorded using a Videomex-V image analytic system automatically.For bromodeoxyuridine (BrdU;thymidine analog as a marker for dividing cells) labeling,the mice were injected with BrdU (100 mg/kg,ip,twice per d for 2 d),and the hippocampal neurogenesis in stressed mice was measured by immunohistochemistry.The proliferation of cultured hippocampal progenitor cells from neonatal rats was determined by colorimetric assay (cell counting kit-8) and 3H-thymidine incorporation assay.Results:After the onset of chronic stress,the locomotor activity of the mice in the open field significantly decreased,while coadministration of agmatine 10 mg/kg (po) blocked it.Furthermore,the number of BrdU-labeled cells in the hippocampal dentate gyrus significantly decreased in chronically stressed mice, which was also blocked by chronic coadministration with agmatine 10 mg/kg (po). Four weeks after the BrdU injection, some of the new born cells matured and became neurons, as determined by double labeling for BrdU and neuron specific enolase (NSE), a marker for mature neurons.In vitro treatment with agmatine 0.1-10 μmo1/L for 3 d significantly increased the proliferation of the cultured hippocampal progenitor cells in a dose-dependent manner.Conclusion:We have found that agmatine increases proliferation of hippocampal progenitor cells in vitro and the hippocampal neurogenesis in vivo in chronically stressed mice.This may be one of the important mechanisms involved in agmatine's antidepressant action.

  20. Antimalarial effect of agmatine on Plasmodium berghei K173 strain

    Institute of Scientific and Technical Information of China (English)

    SURui-Bin; WEIXiao-Li; LIUYin; LIJin

    2003-01-01

    AIM: To study the antimalarial effect of agmatine (Agm) on chloroquine-susceptible Plasmodium berghei K173strain (S strain) and the P berghei K173 resistant strain (R strain). METHODS: The antimalarial effects of Agm onP berghei K173 S strain and R strain were evaluated by Peters 4-d suppression test in mice. RESULTS: Agm(12.5-200 mg/kg,ig,daily) decreased the parasitemia for both P berghei K173 S strain (IC50=139 mg/kg) and Rstrain (IC50=126mg/kg) in mice. Subcutaneous injection (sc) of Agm (5-40mg/kg,tid) showed relatively strongerantimalarial effect than intragastric gavage (IC50=30 mg/kg) in P berghei K 173 S strain. Spermidine antagonized theantimalarial effect of Agm for P berghei K173 S strain and R strain. Agm did not reverse the chloroquine resistanceof P berghei K173 S strain, dl-α-Difluoromethylornithine (DFMO, sc) decreased the parasitemia of P BergheiK173 S strain and this effect was antagonized by spermidine. CONCLUSION: Agm has an antimalarial effect andthe mechanism is related to its inhibition of polyamine synthesis.

  1. Impact of Sn/F Pre-Treatments on the Durability of Protective Coatings against Dentine Erosion/Abrasion.

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    Carolina Ganss

    Full Text Available For preventing erosive wear in dentine, coating with adhesives has been suggested as an alternative to fluoridation. However, clinical studies have revealed limited efficacy. As there is first evidence that Sn(2+ increases bond strength of the adhesive Clearfil SE (Kuraray, the aim of the present study was to investigate whether pre-treatment with different Sn(2+/F(- solutions improves the durability of Clearfil SE coatings. Dentine samples (eight groups, n=16/group were freed of smear layer (0.5% citric acid, 10 s, treated (15 s either with no solution (control, aminefluoride (AmF, 500 ppm F(-, pH 4.5, SnCl2 (800/1600 ppm Sn(2+; pH 1.5, SnCl2/AmF (500 ppm F(-, 800 ppm Sn(2+, pH 1.5/3.0/4.5, or Elmex Erosion Protection Rinse (EP, 500 ppm F-, 800 ppm Sn(2+, pH 4.5; GABA International, then rinsed with water (15 s and individually covered with Clearfil SE. Subsequently the specimens were subjected to an erosion/abrasion protocol consisting of 1320 cycles of immersion in 0.5% citric acid (5 °C/55 °C; 2 min and automated brushing (15 s, 200 g, NaF-toothpaste, RDA 80. As the coatings proved stable up to 1320 cycles, 60 modified cycles (brushing time 30 min/cycle were added. Wear was measured profilometrically. After SnCl2/AmF, pH 4.5 or EP pre-treatment all except one coating survived. In the other groups, almost all coatings were lost and there was no significant difference to the control group. Pre-treatment with a Sn(2+/F(- solution at pH 4.5 seems able to improve the durability of adhesive coatings, rendering these an attractive option in preventing erosive wear in dentine.

  2. Agmatine promotes expression of brain-derived neurotrophic factor in brainstem facial nucleus in the rat facial nerve injury model

    Institute of Scientific and Technical Information of China (English)

    Li Fang; Wenlong Luo

    2008-01-01

    BACKGROUND: Studies have shown that agmatine can reduce inhibition of neuronal regeneration by increasing cyclic adenosine monophosphate and brain-derived neurotrophic factor (BDNF) in the hippocampus of morphine-dependent rats. The hypothesis that agmatine exerts similar effects on facial nerve injury deserves further analysis.OBJECTIVE: To study the effects of peritoneal agmatine injection on BDNF levels in the rat brainstem after facial nerve injury.DESIGN, TIME AND SETTING: A controlled animal experiment was performed at the Department of Otolaryngology-Head and Neck Surgery at the Second Affiliated Hospital, Chongqing University of Medical Sciences (Chongqing, China), between October and December in 2007.MATERIALS: Twenty-four male Sprague-Dawley rats were randomly divided into a control, a lesion, and an agmatine treatment group, with eight rats in each group. Bilateral facial nerve anastomosis was induced in the lesion and agmatine treatment groups, while the control group remained untreated. A rat BDNF Enzyme-linked immunosorbent assay kit was used to measure BDNF levels in the brainstem facial nucleus.METHODS: Starting on the day of lesion, the agmatine group received a peritoneal injection of 100 mg/kg agmatine, once per day, for a week, whereas rats in the lesion group received saline injections.MAIN OUTCOME MEASURES: BDNF levels in the brainstem containing facial nucleus were measured by ELISA.RESULTS: Twenty-four rats were included in the final analysis without any loss. Two weeks after lesion, BDNF levels were significantly higher in the lesion group than in the control group (P<0.01). A significant increase was noted in the agmatine group compared to the lesion group (P<0.01).CONCLUSION: Agmatine can substantially increase BDNF levels in the rat brainstem after facial nerve injury.

  3. No Protection against DSS-induced Colitis by Short-term Pretreatment with Seal or Fish Oils in Rats

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    Gülen Arslan

    2007-01-01

    Full Text Available Background: Omega-3 (n-3 polyunsaturated fatty acids (PUFAs have modulating effects in several chronic inflammatory conditions. The aim of the present study was to test whether prior short-term dietary supplementation with n-3 (fish or seal oil or n-6 (soy oil PUFA rich oils would protect the development of dextran sulfate sodium (DSS-induced colitis in rats.Methods: Forty-eight male Wistar rats were divided into 6 groups: no intervention, sham, DSS, seal oil + DSS, fi sh oil +DSS and soy oil + DSS. Following 7 days of acclimatisation, 1 mL oil (seal, fish or soy or distilled water (sham was administered by gavage day 8 to 14. Colitis was induced by 5% DSS in drinking water from day 15 to 21. Rats were sacrificed on day 23. Histological colitis (crypt and inflammation scores, faecal granulocyte marker protein (GMP and quantitative fatty acid composition in red blood cells were measured.Results: Pretreatment with fish or seal oils did not significantly influence DSS induced inflammation. In fact, all the oils tended to exacerbate the inflammation. Soy oil increased the mean crypt score (P < 0.04, but not the inflammation score or GMP. The ratio of n-6 to n-3 fatty acids (FAs was 11 to 1 and 10 to 1 in standard diet and in red blood cells of control rats, respectively. Following administration of DSS, the ratio fell in all treatment groups (P < 0.001. The lowest ratios were seen in the groups receiving DSS + fi sh or seal oils (around 6 to 1.Conclusion: Short-term pretreatment with fish or seal oils did not protect against subsequent induction of colitis by DSS in this rat model. Whether the high ratio of n-6 to n-3 FAs in the standard diet concealed effects of n-3 FA supplementation should be further investigated.

  4. Agmatine rescues autistic behaviors in the valproic acid-induced animal model of autism.

    Science.gov (United States)

    Kim, Ji-Woon; Seung, Hana; Kim, Ki Chan; Gonzales, Edson Luck T; Oh, Hyun Ah; Yang, Sung Min; Ko, Mee Jung; Han, Seol-Heui; Banerjee, Sourav; Shin, Chan Young

    2017-02-01

    Autism spectrum disorder (ASD) is an immensely challenging developmental disorder characterized primarily by two core behavioral symptoms of social communication deficits and restricted/repetitive behaviors. Investigating the etiological process and identifying an appropriate therapeutic target remain as formidable challenges to overcome ASD due to numerous risk factors and complex symptoms associated with the disorder. Among the various mechanisms that contribute to ASD, the maintenance of excitation and inhibition balance emerged as a key factor to regulate proper functioning of neuronal circuitry. Interestingly, our previous study involving the valproic acid animal model of autism (VPA animal model) has demonstrated excitatory-inhibitory imbalance (E/I imbalance) due to enhanced differentiation of glutamatergic neurons and reduced GABAergic neurons. Here, we investigated the potential of agmatine, an endogenous NMDA receptor antagonist, as a novel therapeutic candidate in ameliorating ASD symptoms by modulating E/I imbalance using the VPA animal model. We observed that a single treatment of agmatine rescued the impaired social behaviors as well as hyperactive and repetitive behaviors in the VPA animal model. We also observed that agmatine treatment rescued the overly activated ERK1/2 signaling in the prefrontal cortex and hippocampus of VPA animal models, possibly, by modulating over-excitability due to enhanced excitatory neural circuit. Taken together, our results have provided experimental evidence suggesting a possible therapeutic role of agmatine in ameliorating ASD-like symptoms in the VPA animal model of ASD.

  5. Enzymatic Synthesis of Agmatine by Immobilized Escherichia coli Cells with Arginine Decarboxylase Activity

    Institute of Scientific and Technical Information of China (English)

    ZHANG Wei-guo; ZHAO Gen-hai; LIU Jun-zhong; LIU Qian; JIAO Qing-cai

    2011-01-01

    A new method for the enzymatic synthesis of agmatine by immobilized Escherichia coli cells with arginine decarboxylase(ADC)activity was established and a series of optimal reaction conditions was set down.The arginine decarboxylase showed the maximum activity when the pyridoxal phosphate(PLP)concentration was 50 mmol/L,pH=7 and 45 ℃.The arginine decarboxylase exhibited the maximum production efficiency when the substrate concentration was 100 mmol/L and the reaction time was 15 h.It was also observed that the appropriate concentration of Mg2+,especially at 0.5 mmol/L promoted the arginine decarboxylase activity; Mn2+ had little effect on the arginine decarboxylase activity.The inhibition of Cu2+ and Zn2+ to the arginine decarboxylase activity was significant.The immobilized cells were continuously used 6 times and the average conversion rate during the six-time usage was 55.6%.The immobilized cells exhibited favourable operational stability.After optimization,the maximally cumulative amount of agmatine could be up to 20 g/L.In addition,this method can also catalyze D,L-arginine to agmatine,leaving the pure optically D-arginine simultaneously.The method has a very important guiding significance to the enzymatic preparation of agmatine.

  6. Agmatine abolishes restraint stress-induced depressive-like behavior and hippocampal antioxidant imbalance in mice.

    Science.gov (United States)

    Freitas, Andiara E; Bettio, Luis E B; Neis, Vivian B; Santos, Danúbia B; Ribeiro, Camille M; Rosa, Priscila B; Farina, Marcelo; Rodrigues, Ana Lúcia S

    2014-04-01

    Agmatine has been recently emerged as a novel candidate to assist the conventional pharmacotherapy of depression. The acute restraint stress (ARS) is an unavoidable stress situation that may cause depressive-like behavior in rodents. In this study, we investigated the potential antidepressant-like effect of agmatine (10mg/kg, administered acutely by oral route) in the forced swimming test (FST) in non-stressed mice, as well as its ability to abolish the depressive-like behavior and hippocampal antioxidant imbalance induced by ARS. Agmatine reduced the immobility time in the mouse FST (1-100mg/kg) in non-stressed mice. ARS caused an increase in the immobility time in the FST, indicative of a depressive-like behavior, as well as hippocampal lipid peroxidation, and an increase in the activity of hippocampal superoxide dismutase (SOD), glutathione peroxidase (GPx) and glutathione reductase (GR) activities, reduced catalase (CAT) activity and increased SOD/CAT ratio, an index of pro-oxidative conditions. Agmatine was effective to abolish the depressive-like behavior induced by ARS and to prevent the ARS-induced lipid peroxidation and changes in SOD, GR and CAT activities and in SOD/CAT activity ratio. Hippocampal levels of reduced glutathione (GSH) were not altered by any experimental condition. In conclusion, the present study shows that agmatine was able to abrogate the ARS-induced depressive-like behavior and the associated redox hippocampal imbalance observed in stressed restraint mice, suggesting that its antidepressant-like effect may be dependent on its ability to maintain the pro-/anti-oxidative homeostasis in the hippocampus.

  7. Protective effect of pretreatment with thymoquinone against Aflatoxin B1 induced liver toxicity in mice

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    A Nili-Ahmadabadi

    2011-10-01

    Full Text Available "n  Background and the purpose of the study: Thymoquinone (TQ is one of the active components of Nigella sativa. The plant has been used in herbal medicine for treatment of many diseases including liver complications. The present study aimed to investigate protective effects of TQ on Aflatoxin B1 (AFB1 induced liver toxicity in mice. "n  Methods: Animals were divided into six groups and treated intraperitoneally. Group 1 (blank served as vehicle, group 2 (positive control received AFB1, Group 3 was treated with 9 mg/kg of TQ, Groups 4, 5 and 6 were treated with 4.5, 9 and 18 mg/kg of TQ, respectively. After three consecutive days, except for groups 1 and 3, animals were administered with a single dose of AFB1 (2 mg/kg. All the animals were killed 24 hrs following the AFB1 administration under ether anesthesia. Biochemical parameters including AST, ALT and ALP in serum samples and glutathione (GSH and malondialdehyde (MDA contents in liver homogenates were determined. Liver sections were collected for histopathological examination. "n  Results: Findings of this study showed that AST, ALT, ALP and MDA levels were significantly lower in the TQ treated animals as compared to AFB1 group (group 2. Furthermore, TQ was able to recover glutathione content (GSH of liver tissue. The best response, however, was observed with the dose of 9 mg/kg. Liver sections of AFB1 intoxicated mice showed inflammation, necrosis, hyperplasia of kupffer and infiltration of mononuclear cells, dilation of sinusoids and disruption of hepatocytes, while treatment with TQ helped to normalize liver architecture in accordance to biochemical findings. "n  Conclusion: Taken collectively, TQ has a protective role with optimum dose of 9 mg/kg in AFB1 hepatotoxicity.

  8. Myocardial protection during elective coronary artery bypasses grafting by pretreatment with omega-3 polyunsaturated fatty acids

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    Veljović Milić

    2013-01-01

    PUFAs group was statistically significantly higher compared to the control group after 10, 20 and 30 min of reperfusion (35.5% vs 50.4%, p < 0.0004; 25.8 % vs 48.7%, p < 0.0001 and 25.8% vs 45.6%, p < 0.0002, respectively. The level of TnT, 4 and 24 h after CPB, was significantly higher in the control group compared to PUFAs group, with statistically significant differences (11.4 vs 6.6, p < 0.009 and 12.7 vs 5.9, p < 0.008, respectively. The level of CK-MB, 4 h after CPB, was significantly higher in the control group compared to PUFAs group (61.9 vs 37.7, p < 0.008, but its level, 24 h after CPB, was not statistically different between the two groups (58.9 vs 40.6, p < 0.051. Conclusion. Treatment with omega-3 PUFAs administered preoperatively promoted early metabolic recovery of the heart after elective CABG and improved myocardial protection. This study showed that omega-3 emulsion should not be considered only as a nutritional supplement but also as a clinically safe and potent cardioprotective adjunct during CPB.

  9. Cytobiological mechanism of agmatine inhibitory effect on morphine dependence: role of I1-imidazoline receptor

    Institute of Scientific and Technical Information of China (English)

    SuRui-bin; WuNing; LiJin

    2004-01-01

    In our previous studies, agmatine was found to prevent substance dependence of morphine in mice, rats and monkeys,but the exact mechanism was not clear yet. In this study, for the first time rat μ opioid receptor (rMOR) and human I1-imidazoline receptor (hI1 R) were co-expressed stably in CHO cells (CHO-μ/I1) by means of lipofectamine transfection

  10. Neuroprotective effects of receptor imidazoline 2 and its endogenous ligand agmatine

    Institute of Scientific and Technical Information of China (English)

    Wei-Wen QIU; Rong-Yuan ZHENG

    2006-01-01

    Receptor imidazoline 2 (I2) is one of the imidazoline receptors with high affinity for [3H]-idazoxan. Receptor I2,being classified into I2A and I2B subtypes, is mainly localized to the outer membrane of mitochondria in liver, kidney and brain. Receptor I2, displaying high similarity of sequence with monoamine oxidase-B (MAO-B), is structurally related to MAO-B, but the I2 imidazoline binding site (I2BS) with ligand is distinct from the catalytic site of MAO-B. Agmatine is the endogenous ligand of receptor I2. Accumulating evidence have revealed that the activation of receptors I2 may produce neuroprotective effects by increasing expression of glial fibrillary acidic protein (GFAP) in astrocytes, inhibiting activity of MAO, reducing calcium overload in cells. Agmatine exerts neuroprotection against ischemia-hypoxia, injury, glutamateinduced neurotoxicity by activating imidazoline receptors, blocking N-methyl-D-aspartate (NMDA) receptor, inhibiting all isoforms of nitric oxide synthase (NOS), and selectively blocking the voltage-gated calcium channels (VGCC). It would be expected that agmatine is one of the potential neuroprotective agents.

  11. Endogenous Inactivators of Arginase, l-Arginine Decarboxylase, and Agmatine Amidinohydrolase in Evernia prunastri Thallus 1

    Science.gov (United States)

    Legaz, María Estrella; Vicente, Carlos

    1983-01-01

    Arginase (EC 3.5.3.1), l-arginine decarboxylase (EC 4.1.1.19), and agmatine amidinohydrolase (EC 3.5.3.11) activities spontaneously decay in Evernia prunastri thalli incubated on 40 millimolar l-arginine used as inducer of the three enzymes if dithiothreitol is not added to the media. Lichen thalli accumulate both chloroatranorin and evernic acid in parallel to the loss of activity. These substances behave as inactivators of the enzymes at a range of concentrations between 2 and 20 micromolar, whereas several concentrations of dithiothreitol reverse, to some extent, the in vitro inactivation. PMID:16662821

  12. Endogenous Inactivators of Arginase, l-Arginine Decarboxylase, and Agmatine Amidinohydrolase in Evernia prunastri Thallus.

    Science.gov (United States)

    Legaz, M E; Vicente, C

    1983-02-01

    Arginase (EC 3.5.3.1), l-arginine decarboxylase (EC 4.1.1.19), and agmatine amidinohydrolase (EC 3.5.3.11) activities spontaneously decay in Evernia prunastri thalli incubated on 40 millimolar l-arginine used as inducer of the three enzymes if dithiothreitol is not added to the media. Lichen thalli accumulate both chloroatranorin and evernic acid in parallel to the loss of activity. These substances behave as inactivators of the enzymes at a range of concentrations between 2 and 20 micromolar, whereas several concentrations of dithiothreitol reverse, to some extent, the in vitro inactivation.

  13. Identification of functional amino acid residues involved in polyamine and agmatine transport by human organic cation transporter 2.

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    Kyohei Higashi

    Full Text Available Polyamine (putrescine, spermidine and spermine and agmatine uptake by the human organic cation transporter 2 (hOCT2 was studied using HEK293 cells transfected with pCMV6-XL4/hOCT2. The Km values for putrescine and spermidine were 7.50 and 6.76 mM, and the Vmax values were 4.71 and 2.34 nmol/min/mg protein, respectively. Spermine uptake by hOCT2 was not observed at pH 7.4, although it inhibited both putrescine and spermidine uptake. Agmatine was also taken up by hOCT2, with Km value: 3.27 mM and a Vmax value of 3.14 nmol/min/mg protein. Amino acid residues involved in putrescine, agmatine and spermidine uptake by hOCT2 were Asp427, Glu448, Glu456, Asp475, and Glu516. In addition, Glu524 and Glu530 were involved in putrescine and spermidine uptake activity, and Glu528 and Glu540 were weakly involved in putrescine uptake activity. Furthermore, Asp551 was also involved in the recognition of spermidine. These results indicate that the recognition sites for putrescine, agmatine and spermidine on hOCT2 strongly overlap, consistent with the observation that the three amines are transported with similar affinity and velocity. A model of spermidine binding to hOCT2 was constructed based on the functional amino acid residues.

  14. Agmatine block voltage-gated calcium channels and acid sensing ion channels in the cultured hippocampal neuron

    Institute of Scientific and Technical Information of China (English)

    WENGXie-Chuan; ZHENGJian-Quan; GAIXiao-Dan; LIJin; XiaoWen-Bin

    2004-01-01

    Agrnatine was first identified and characterized as a candidate for CDS (clonidine displacing substance) in the bovine brain in 1994. The following researches demonstrated that agmatine was a widely distributed endogenous substance and performed a lot of biological functions in the central nervous system. The evidence revealed its targets were diverse and its

  15. Selection of hemicellulosic hydrolysate pretreatments and fermentation conditions to stimulate xylitol protection by ethanol-producing yeasts

    Energy Technology Data Exchange (ETDEWEB)

    Converti, A. [Ist. di Ingegneria Chimica e di Processo `G.B. Bonino`, Facolta di Ingegneria, Univ. degli Studi di Genova (Italy); Del Borghi, M. [Ist. di Ingegneria Chimica e di Processo `G.B. Bonino`, Facolta di Ingegneria, Univ. degli Studi di Genova (Italy)

    1996-12-31

    Xylitol production from hardwood hemicellulosic hydrolysates by well-known ethanol-producing yeasts was stimulated through an experimental schedule including pretreatments of the hydrolysate, the choice of the best xylitol producer and the selection of the optimum fermentation conditions. The xylitol or ethanol yields obtained on consumed xylose demonstrated that their production was stimulated under completely different conditions, as to be expected by the fact that these catabolites are the final products of different metabolic pathways. In particular, the catabolism of Pachysolen tannophilus, that is the best ethanol producer from this natural substrate, could be targeted towards xylitol rather than towards ethanol production by ensuring a strongly reducing environment through a suitable pretreatment of the hydrolysate. The final removal of fermentation inhibitors by adsorption onto highly adsorbing substances allowed a further 20% xylitol yield increase. (orig.)

  16. Captopril pretreatment protects the lung against severe acute pancreatitis induced injury via inhibiting angiotensin II production and suppressing Rho/ROCK pathway.

    Science.gov (United States)

    Yu, Qi-Hong; Guo, Jie-Fang; Chen, Yan; Guo, Xiao-Rong; Du, Yi-Qi; Li, Zhao-Shen

    2016-09-01

    Acute pancreatitis (AP) usually causes acute lung injury, which is also known as acute pancreatitis associated lung injury (APALI). This study aimed to investigate whether captopril pretreatment was able to protect lung against APALI via inhibiting angiotensin II (Ang II) production and suppressing Rho/ROCK (Rho kinase) pathway in rats. Severe AP (SAP) was introduced to rats by bile-pancreatic duct retrograde injection of 5% sodium taurocholate. Rats were randomly divided into three groups. In the sham group, sham operation was performed; in the SAP group, SAP was introduced; in the pre-cpl + SAP group, rats were intragastrically injected with 5 mg/kg captopril 1 hour prior to SAP induction. Pathological examination of the lung and pancreas, evaluation of pulmonary vascular permeability by wet/dry ratio and Evans Blue staining, detection of serum amylase, Western blot assay for Ang II receptor type 1 (AT1), RhoA, ROCK (Rho kinase), and MLCK (myosin light chain kinase) were performed after the animals were sacrificed at 24 hours. After the surgery, characteristic findings of pancreatitis were observed, accompanied by lung injury. The serum amylase, Ang II, and lung expression of AT1, RhoA, ROCK, and MLCK increased dramatically in SAP rats. However, captopril pretreatment improved the histological changes, reduced the pathological score of the pancreas and lung, inhibited serum amylase and Ang II production, and decreased expression of AT1, RhoA, ROCK, and MLCK in the lung. These findings suggest that captopril pretreatment is able to protect the lung against APALI, which is, at least partially, related to the inhibition of Ang II production and the suppression of the Rho/ROCK pathway.

  17. Involvement of nitric oxide in anticompulsive-like effect of agmatine on marble-burying behaviour in mice.

    Science.gov (United States)

    Gawali, Nitin B; Chowdhury, Amrita A; Kothavade, Pankaj S; Bulani, Vipin D; Nagmoti, Dnyaneshwar M; Juvekar, Archana R

    2016-01-01

    In view of the reports that nitric oxide modulates the neurotransmitters implicated in obsessive-compulsive disorder (OCD), patients with OCD exhibit higher plasma nitrate levels, and drugs useful in OCD influence nitric oxide. Agmatine is a polyamine and widely distributed in mammalian brain which interacts with nitrergic systems. Hence, the present study was carried out to understand the involvement of nitrergic systems in the anticompulsive-like effect of agmatine. We used marble-burying behaviour (MBB) of mice as the animal model of OCD, and nitric oxide levels in hippocampus (HC) and cortex homogenate were measured. Results revealed that, agmatine (20 and 40mg/kg, i.p) significantly inhibited the MBB. Intraperitoneal administration of nitric oxide enhancers viz. nitric oxide precursor - l-arginine (l-ARG) (400mg/kg and 800mg/kg) increased MBB as well as brain nitrites levels, whereas treatment with N(G)-nitro-l-arginine methyl ester (l-NAME) neuronal nitric oxide synthase inhibitor (30mg/kg and 50mg/kg, i.p.) and 7-nitroindazole (7-NI) (20mg/kg and 40mg/kg) attenuated MBB and nitrites levels in brain. Further, in combination studies, the anticompulsive-like effect of agmatine (20mg/kg, ip) was exacerbated by prior administration of l-ARG (400mg/kg) and conversely l-NAME (15mg/kg) or 7-NI (10.0mg/kg) attenuated OCD-like behaviour with HC and cortex changes in the levels of NO. None of the above treatment had any significant influence on locomotor activity. In conclusion, Agmatine is effective in ameliorating the compulsive-like behaviour in mice which appears to be related to nitric oxide in brain.

  18. Prophylactic pretreatment of mice with hematopoietic growth factors induces expansion of primitive cell compartments and results in protection against 5-fluorouracil-induced toxicity.

    Science.gov (United States)

    de Haan, G; Donte, B; Engel, C; Loeffler, M; Nijhof, W

    1996-06-01

    second dose of 5-FU given respectively after 7 or 10 days. To assess whether chemoprotection in this setting could be ascribed to protection of the hematopoietic system, we transplanted a high number of normal bone marrow cells (sufficient to compensate for any hematopoietic deficiency) to normal and pretreated mice after they had been administered 2 doses of 5-FU, given 7 days apart. Bone marrow transplantation (BMT) could only rescue 50% of mice not pretreated, showing that a significant part of the mortality was because of nonhematologic toxicity. However, a BMT given to growth factor pretreated mice saved all mice, indicating that in this setting SCF + IL-11 had additional protective effects on cell systems other than hematopoiesis. In conclusion, our study showed fundamental knowledge about the behavior of primitive cells in vivo and has shown that manipulation of these and other cell compartments with appropriate growth factors may confer resistance against cytotoxic drugs.

  19. Biomass pretreatment

    Science.gov (United States)

    Hennessey, Susan Marie; Friend, Julie; Elander, Richard T; Tucker, III, Melvin P

    2013-05-21

    A method is provided for producing an improved pretreated biomass product for use in saccharification followed by fermentation to produce a target chemical that includes removal of saccharification and or fermentation inhibitors from the pretreated biomass product. Specifically, the pretreated biomass product derived from using the present method has fewer inhibitors of saccharification and/or fermentation without a loss in sugar content.

  20. Hypoxia pretreatment and EPO-modification enhance the protective effects of MSC on neuron-like PC12 cells in a similar way.

    Science.gov (United States)

    Feng, Jinli; Wang, Wei

    2017-01-08

    Mesenchymal stem cells (MSC) based cell transplantation therapy is proved to be an attractive strategy with great potential for improvement of hypoxia induced neural damage. In the present study, MSCs were co-culture with PC12 to investigate its protective effects against hypoxia pretreatment, and the Lactate dehydrogenase (LDH) release assay, MTT and Anexin V staining were performed to analysis the cellular damage or apoptotic. RT-PCR and Western blotting were further used to investigate the underlying mechanism. The results indicate that hypoxia treatment results in the decrease of PC12 cell viability, yet co-culture with MSC could protect the PC12 from hypoxia induced damage. Hypoxia pre-activated or EPO transduced MSC with up-regulated erythropoietin (EPO) expression could further enhance MSC's protective effect against hypoxia induced cell damage, which was associated with high level of anti-apoptotic p-Akt and ration Bcl-2/Bax, and decreased Caspase 3 in PC12. Taken together, these data suggests high levels of MSC-mediated cyto-protection is closely tied to high gene expression levels of EPO. The up-regulation of EPO for enhanced MSC-mediated cyto-protection may has great potential for the MSC cellular therapy of neural or neuronal injuries induced by hypoxia.

  1. Spirulina maxima pretreatment partially protects against 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine neurotoxicity.

    Science.gov (United States)

    Chamorro, Germán; Pérez-Albiter, Mónica; Serrano-García, Norma; Mares-Sámano, José J; Rojas, Patricia

    2006-01-01

    Spirulina is an alga that has a high nutritional value and some of its biological activities are attributed to the presence of antioxidants. Oxidative stress is involved in Parkinson's disease. This study aims at evaluating the neuroprotective role of Spirulina maxima (Sp.) against 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) neurotoxicity, used as a model of Parkinson's disease. Ninety-six male C-57 black mice were pretreated with Spirulina for 14 days (25, 50, 100, 150 or 200 mg/kg, oral), followed by three MPTP administrations (30 mg/kg, intraperitoneal, i.p.). Animals were given Sp. for 8 additional days. After the treatment, the striatal dopamine (DA) content was analysed by high performance liquid chromatography, and lipid peroxidation was studied as an index of oxidative stress. Sp. pretreatment at 150 mg/kg partially prevented (51%) the DA-depleting effect of MPTP and blocked oxidative stress. Spirulina partially prevents MPTP neurotoxicity and oxidative stress, suggesting it could be a possible alternative in experimental therapy.

  2. Pre-treatment with cardamonin protects against cisplatin-induced nephrotoxicity in rats: Impact on NOX-1, inflammation and apoptosis

    Energy Technology Data Exchange (ETDEWEB)

    El-Naga, Reem N., E-mail: reemelnaga@hotmail.com

    2014-01-01

    Cisplatin is an effective anti-cancer drug; however, its clinical use is usually associated with nephrotoxicity as a dose-limiting side effect. Several molecular mechanisms have been found to be involved in this nephrotoxicity such as oxidative stress, inflammation and apoptosis. The aim of this study was to explore the potential nephroprotective effect of cardamonin, a flavone found in Alpinia plant, in a rat model of cisplatin-induced nephrotoxicity. The possible mechanisms underlying this nephroprotective effect were investigated. Cardamonin was given at two different doses; 10 and 30 mg/kg orally for two weeks, starting one week before giving a single nephrotoxic dose of cisplatin (7 mg/kg). Acute nephrtoxicity was evident by significantly increased blood urea nitrogen and serum creatinine levels. Also, cisplatin increased lipid peroxidation and depleted reduced glutathione level and superoxide dismutase. Additionally, cisplatin showed a marked pro-inflammatory response as evidenced by significant increase in tissue levels of IL-1β, TNF-α, NF-kB, iNOS, ICAM-1 and MCP-1. Pre-treatment with cardamonin significantly attenuated the nephrotoxic effects, oxidative stress and inflammation induced by cisplatin, in a dose-dependent manner. Also, cardamonin decreased caspase-3 expression and Bax/Bcl-2 ratio as compared to cisplatin group. Besides, cradamonin reversed cisplatin-induced decrease in EGF. Furthermore, up-regulation of NOX-1 was found to be involved in cisplatin-induced nephrotoxicity and its expression was significantly reduced by cardamonin. Histopathological examination further confirmed the nephroprotective effect of cardamonin. Moreover, pre-treatment with subtoxic concentration of cardamonin has significantly enhanced cisplatin cytotoxic activity in four different human cancer cell lines; hela, hepG2, PC3 and HCT116 cancer cell lines. In conclusion, these findings suggest that cardamonin improves therapeutic index of cisplatin and that NOX-1 is

  3. Pretreatment with adenosine and adenosine A1 receptor agonist protects against intestinal ischemia-reperfusion injury in rat

    Institute of Scientific and Technical Information of China (English)

    V Haktan Ozacmak; Hale Sayan

    2007-01-01

    AIM: To examine the effects of adenosine and A1 receptor activation on reperfusion-induced small intestinal injury.METHODS: Rats were randomized into groups with sham operation, ischemia and reperfusion, and systemic treatments with either adenosine or 2-chloro-N6-cyclopentyladenosine, A1 receptor agonist or 8-cyclopentyl-1,3-dipropylxanthine, A1 receptor antagonist, plus adenosine before ischemia. Following reperfusion, contractions of ileum segments in response to KCl, carbachol and substance P were recorded. Tissue myeloperoxidase,malondialdehyde, and reduced glutathione levels were measured.RESULTS: Ischemia significantly decreased both contraction and reduced glutathione level which were ameliorated by adenosine and agonist administration. Treatment also decreased neutrophil infiltration and membrane lipid peroxidation. Beneficial effects of adenosine were abolished by pretreatment with A1 receptor antagonist.CONCLUSION: The data suggest that adenosine and A1 receptor stimulation attenuate ischemic intestinal injury via decreasing oxidative stress, lowering neutrophil infiltration, and increasing reduced glutathione content.

  4. Lime Pretreatment

    Science.gov (United States)

    Sierra, Rocio; Granda, Cesar Benigno; Holtzapple, Mark T.

    Lime pretreatment has proven to be a useful method for selectively reducing the lignin content of lignocellulosic biomass without significant loss in carbohydrates, thus realizing an important increase in biodigestibility. In lime pretreatment, the biomass is pretreated with calcium hydroxide and water under different conditions of temperature and pressure. It can be accomplished in one of three fashions: (1) short-term pretreatment that lasts up to 6 h, requires temperatures of 100-160°C, and can be applied with or without oxygen (pressure ~200 psig); (2) long-term pretreatment taking up to 8 weeks, requiring only 55-65°C, and capable of running with or without air (atmospheric pressure); and (3) simple pretreatment requiring 1 h in boiling water, without air or oxygen. Nonoxidative conditions are effective at low lignin contents (below ~18% lignin), whereas oxidative conditions are required for high lignin contents (above ~18% lignin).

  5. Improved method for HPLC analysis of polyamines, agmatine and aromatic monoamines in plant tissue

    Science.gov (United States)

    Slocum, R. D.; Flores, H. E.; Galston, A. W.; Weinstein, L. H.

    1989-01-01

    The high performance liquid chromatographic (HPLC) method of Flores and Galston (1982 Plant Physiol 69: 701) for the separation and quantitation of benzoylated polyamines in plant tissues has been widely adopted by other workers. However, due to previously unrecognized problems associated with the derivatization of agmatine, this important intermediate in plant polyamine metabolism cannot be quantitated using this method. Also, two polyamines, putrescine and diaminopropane, also are not well resolved using this method. A simple modification of the original HPLC procedure greatly improves the separation and quantitation of these amines, and further allows the simulation analysis of phenethylamine and tyramine, which are major monoamine constituents of tobacco and other plant tissues. We have used this modified HPLC method to characterize amine titers in suspension cultured carrot (Daucas carota L.) cells and tobacco (Nicotiana tabacum L.) leaf tissues.

  6. Pretreatment with Fucoidan from Fucus vesiculosus Protected against ConA-Induced Acute Liver Injury by Inhibiting Both Intrinsic and Extrinsic Apoptosis.

    Science.gov (United States)

    Li, Jingjing; Chen, Kan; Li, Sainan; Liu, Tong; Wang, Fan; Xia, Yujing; Lu, Jie; Zhou, Yingqun; Guo, Chuanyong

    2016-01-01

    This study aimed to explore the effects of fucoidan from Fucus vesiculosus on concanavalin A (ConA)-induced acute liver injury in mice. Pretreatment with fucoidan protected liver function indicated by ALT, AST and histopathological changes by suppressing inflammatory cytokines, such as tumor necrosis factor alpha (TNF-α) and interferon gamma (IFN-γ). In addition, intrinsic and extrinsic apoptosis mediated by Bax, Bid, Bcl-2, Bcl-xL and Caspase 3, 8, and 9 were inhibited by fucoidan and the action was associated with the TRADD/TRAF2 and JAK2/STAT1 signal pathways. Our results demonstrated that fucoidan from Fucus vesiculosus alleviated ConA-induced acute liver injury via the inhibition of intrinsic and extrinsic apoptosis mediated by the TRADD/TRAF2 and JAK2/STAT1 pathways which were activated by TNF-α and IFN-γ. These findings could provide a potential powerful therapy for T cell-related hepatitis.

  7. Association of high expression in rat gastric mucosal heat shock protein 70 induced by moxibustion pretreatment with protection against stress injury

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    AIM: To study the effect of moxibustion on Zusanli or Liangmeng point on gastric mucosa injury in stressinduced ulcer rats and its correlation with the expression of heat shock protein 70 (HSP70).METHODS: Sixty healthy SD rats (30 males, 30 females)were divided into control group, injury model group,Zushanli point group, Liangmeng point group. Stress gastric ulcer model was induced by binding cold stress method. Gastric mucosa ulcer injury (UI) index was calculated by Guth method. Gastric mucosa blood flow (GMBF) was recorded with a biological signal analyzer.Protein content and gene expression in gastric mucosal HSP70 were detected by immunohistochemistry (IHC)and reverse transcription polymerase chain reaction (RT-PCR). Thiobarbital method was used to determine malondialdehyde (MDA) content. Gastric mucosal endothelin (ET) and prostaglandin E2 (PGE2) were analyzed by radioimmunoassay.RESULTS: High gastric mucosal UI index, high HSP70 expression, low GMBF and PGF2, elevated MDA and ET were observed in gastric mucosa of rats subjected to cold stress. Moxibustion on Zusanli or Liangmeng point decreased rat gastric mucosal UI index, MDA and ET.Conversely, the expression of HSP70, GMBF, and PGE2 was elevated in gastric mucosa after pretreatment with moxibustion on Zusanli or Liangmeng point. The observed parameters were significantly different between Zusanli and Liangmeng points.CONCLUSION: Pretreatment with moxibustion on Zusanli or Liangmeng point protects gastric mucosa against stress injury. This protection is associated with the higher expression of HSP70 mRNA and protein,leading to release of PGE2 and inhibition of MDA and ET,impairment of gastric mucosal index.

  8. Pretreatment with Tongxinluo protects porcine myocardium from ischaemia/reperfusion injury through a nitric oxide related mechanism

    Institute of Scientific and Technical Information of China (English)

    CHENG Yu-tong; YANG Yue-jin; ZHANG Hai-tao; QIAN Hai-yan; ZHAO Jing-lin; MENG Xian-min; LUO Fu-liang; WU Yi-ling

    2009-01-01

    Background The traditional Chinese medicine Tongxinluo can protect myocardium against ischaemia/reperfusion injury, but the mechanism of its action is not well documented. We examined the involvement of nitric oxide in the protective role of Tongxinluo. Methods Miniswine were randomized to four groups of seven: sham, control, Tongxinluo and Tongxinluo coadministration with a nitric oxide synthase inhibitor Nω-nitro-L-arginine (L-NNA, 10 mg/kg i.v.). Three hours after administration of Tongxinluo, the animals were anaesthetised and the left anterior descending coronary artery ligated and maintained in situ for 90 minutes followed by 3 hours of reperfusion before death. Area of no reflow and necrosis and risk region were determined pathologically by planimetry. The degree of neutrophil accumulation in myocardium was obtained by measuring myeloperoxidase activity and histological analysis. Myocardial endothelial nitric oxide synthase activity and vascular endothelial cadherin content were measured by colorimetric method and immunoblotting analysis respectively.Results Tongxinluo significantly increased the local blood flow and limited the infarct and size of no reflow. Tongxinluo also attenuated myeloperoxidase activity and neutrophil accumulation in histological sections and maintained the level of vascular endothelial cadherin and endothelial nitric oxide synthase activity in the reflow region when compared with control group. The protection of Tongxinluo was counteracted by coadministration with L-NNA. Conclusions Tongxinluo may limit myocardial ischaemia and protect the heart against reperfusion injury. Tongxinluo regulates synthesis of nitric oxide by altering activity of endothelial nitric oxide synthase.

  9. Pretreatment with remifentanil protects against the reduced-intestinal contractility related to the ischemia and reperfusion injury in rat

    Directory of Open Access Journals (Sweden)

    Hale Sayan-Ozacmak

    2015-12-01

    Full Text Available BACKGROUND AND OBJECTIVES: Serious functional and structural alterations of gastrointestinal tract are observed in failure of blood supply, leading to gastrointestinal dismotility. Activation of opioid receptors provides cardioprotective effect against ischemia-reperfusion (I/R injury. The aim of the present study was to determine whether or not remifentanil could reduce I/R injury of small intestine. METHODS: Male Wistar Albino rats were subjected to mesenteric ischemia (30 min followed by reperfusion (3 h. Four groups were designed: sham control; remifentanil alone; I/R control; and remifentanil + I/R. Animals in remifentanil + I/R group were subjected to infusion of remifentanil (2 ug kg-1 min-1 for 60 min, half of which started before inducing ischemia. Collecting the ileum tissues, evaluation of damage was based on contractile responses to carbachol, levels of lipid peroxidation and neutrophil infiltration, and observation of histopathological features in intestinal tissue. RESULTS: Following reperfusion, a significant decrease in carbachol-induced contractile response, a remarkable increase in both lipid peroxidation and neutrophil infiltration, and a significant injury in mucosa were observed. An average contractile response of remifentanil + I/R group was significantly different from that of the I/R group. Lipid peroxidation and neutrophil infiltration were also significantly suppressed by the treatment. The tissue samples of the I/R group were grade 4 in histopathological evaluation. In remifentanil + I/R group, on the other hand, the mucosal damage was moderate, staging as grade 1. CONCLUSIONS: The pretreatment with remifentanil can attenuate the intestinal I/R injury at a remarkable degree possibly by lowering lipid peroxidation and leukocyte infiltration.

  10. Influence of the surface pre-treatment of aluminum on the processes of formation of cerium oxides protective films

    Science.gov (United States)

    Andreeva, R.; Stoyanova, E.; Tsanev, A.; Stoychev, D.

    2016-03-01

    It is known that there is special interest in the contemporary investigations on conversion treatment of aluminum aimed at promoting its corrosion stability, which is focused on electrolytes on the basis of salts of metals belonging to the group of rare-earth elements. Their application is especially attractive, as it enables a successful substitution of the presently applied highly efficient, but at the same time toxic Cr6+-containing electrolytes. The present paper presents a study on the influence of the preliminary alkaline activation and acidic de-oxidation of the aluminum surface on the processes of immersion formation of protective cerium oxides films on Al 1050. The results obtained show that their deposition from simple electrolytes (containing only salts of Ce3+ ions) on the Al surface, treated only in alkaline solution, occurs at a higher rate, which leads to preparing thicker oxide films having a better protective ability. In the cases when the formation of oxide films is realized in a complex electrolyte (containing salts of Ce3+ and Cu2+ ions), better results are obtained with respect to the morphology and protective action of cerium oxides film on samples that have been consecutively activated in alkaline solution and deoxidized in acidic solution. Electrochemical investigations were carried out in a model corrosion medium (0.1 M NaCl); it was shown that the cerium protective films, deposited by immersion, have a cathodic character with regard to the aluminum support and inhibit the occurrence of the depolarizing corrosion process -- the reaction of oxygen reduction.

  11. Periodic 17β-estradiol pretreatment protects rat brain from cerebral ischemic damage via estrogen receptor-β.

    Directory of Open Access Journals (Sweden)

    Ami P Raval

    Full Text Available Although chronic 17β-estradiol (E2 has been shown to be a cognition-preserving and neuroprotective agent in animal brain injury models, concern regarding its safety was raised by the failed translation of this phenomenon to the clinic. Previously, we demonstrated that a single bolus of E2 48 hr prior to ischemia protected the hippocampus from damage in ovariectomized rats via phosphorylation of cyclic-AMP response element binding protein, which requires activation of estrogen receptor subtype beta (ER-β. The current study tests the hypothesis that long-term periodic E2-treatment improves cognition and reduces post-ischemic hippocampal injury by means of ER-β activation. Ovariectomized rats were given ten injections of E2 at 48 hr intervals for 21 days. Hippocampal-dependent learning, memory and ischemic neuronal loss were monitored. Results demonstrated that periodic E2 treatments improved spatial learning, memory and ischemic neuronal survival in ovariectomized rats. Additionally, periodic ER-β agonist treatments every 48 hr improved post-ischemic cognition. Silencing of hippocampal ER-β attenuated E2-mediated ischemic protection suggesting that ER-β plays a key role in mediating the beneficial effects of periodic E2 treatments. This study emphasizes the need to investigate a periodic estrogen replacement regimen to reduce cognitive decline and cerebral ischemia incidents/impact in post-menopausal women.

  12. Protective effect of cholesterol-loaded cyclodextrin pretreatment against hydrogen peroxide induced oxidative damage in ram sperm.

    Science.gov (United States)

    Naseer, Zahid; Ahmad, Ejaz; Aksoy, Melih; Küçük, Niyazi; Serin, İlker; Ceylan, Ahmet; Boyacıoğlu, Murat; Kum, Cavit

    2015-08-01

    Three experiments were conducted to determine the protective effect of cholesterol-loaded cyclodextrin (CLC) against hydrogen peroxide (H2O2) or cryo-induced damage in ram sperm. In Experiment 1, the fresh ejaculates were either treated with CLC or remained untreated. Both CLC treated and untreated samples were then incubated with 0, 250 or 500 μM H2O2 at 35°C for 12 h. After incubation period of 12 h, the motility, viability and membrane integrity remained higher in CLC treated sperm even in the presence of 250 or 500 μM H2O2. The H2O2 treatment affected all the sperm parameters adversely (P0.05) in MDA level was observed among the groups at any stage of incubation. In conclusion, the CLC incorporation in ram sperm membrane may protects it against H2O2 or cryo-induced oxidative damage. The cryoprotective influence of CLC on ram sperm might be resulted from, at least partly, its antioxidative property.

  13. Pretreatment with Fucoidan from Fucus vesiculosus Protected against ConA-Induced Acute Liver Injury by Inhibiting Both Intrinsic and Extrinsic Apoptosis.

    Directory of Open Access Journals (Sweden)

    Jingjing Li

    Full Text Available This study aimed to explore the effects of fucoidan from Fucus vesiculosus on concanavalin A (ConA-induced acute liver injury in mice. Pretreatment with fucoidan protected liver function indicated by ALT, AST and histopathological changes by suppressing inflammatory cytokines, such as tumor necrosis factor alpha (TNF-α and interferon gamma (IFN-γ. In addition, intrinsic and extrinsic apoptosis mediated by Bax, Bid, Bcl-2, Bcl-xL and Caspase 3, 8, and 9 were inhibited by fucoidan and the action was associated with the TRADD/TRAF2 and JAK2/STAT1 signal pathways. Our results demonstrated that fucoidan from Fucus vesiculosus alleviated ConA-induced acute liver injury via the inhibition of intrinsic and extrinsic apoptosis mediated by the TRADD/TRAF2 and JAK2/STAT1 pathways which were activated by TNF-α and IFN-γ. These findings could provide a potential powerful therapy for T cell-related hepatitis.

  14. Lignocellulosic Biomass Pretreatment Using AFEX

    Science.gov (United States)

    Balan, Venkatesh; Bals, Bryan; Chundawat, Shishir P. S.; Marshall, Derek; Dale, Bruce E.

    Although cellulose is the most abundant organic molecule, its susceptibility to hydrolysis is restricted due to the rigid lignin and hemicellulose protection surrounding the cellulose micro fibrils. Therefore, an effective pretreatment is necessary to liberate the cellulose from the lignin-hemicellulose seal and also reduce cellulosic crystallinity. Some of the available pretreatment techniques include acid hydrolysis, steam explosion, ammonia fiber expansion (AFEX), alkaline wet oxidation, and hot water pretreatment. Besides reducing lignocellulosic recalcitrance, an ideal pretreatment must also minimize formation of degradation products that inhibit subsequent hydrolysis and fermentation. AFEX is an important pretreatment technology that utilizes both physical (high temperature and pressure) and chemical (ammonia) processes to achieve effective pretreatment. Besides increasing the surface accessibility for hydrolysis, AFEX promotes cellulose decrystallization and partial hemicellulose depolymerization and reduces the lignin recalcitrance in the treated biomass. Theoretical glucose yield upon optimal enzymatic hydrolysis on AFEX-treated corn stover is approximately 98%. Furthermore, AFEX offers several unique advantages over other pretreatments, which include near complete recovery of the pretreatment chemical (ammonia), nutrient addition for microbial growth through the remaining ammonia on pretreated biomass, and not requiring a washing step during the process which facilitates high solid loading hydrolysis. This chapter provides a detailed practical procedure to perform AFEX, design the reactor, determine the mass balances, and conduct the process safely.

  15. Lignocellulosic biomass pretreatment using AFEX.

    Science.gov (United States)

    Balan, Venkatesh; Bals, Bryan; Chundawat, Shishir P S; Marshall, Derek; Dale, Bruce E

    2009-01-01

    Although cellulose is the most abundant organic molecule, its susceptibility to hydrolysis is restricted due to the rigid lignin and hemicellulose protection surrounding the cellulose micro fibrils. Therefore, an effective pretreatment is necessary to liberate the cellulose from the lignin-hemicellulose seal and also reduce cellulosic crystallinity. Some of the available pretreatment techniques include acid hydrolysis, steam explosion, ammonia fiber expansion (AFEX), alkaline wet oxidation, and hot water pretreatment. Besides reducing lignocellulosic recalcitrance, an ideal pretreatment must also minimize formation of degradation products that inhibit subsequent hydrolysis and fermentation. AFEX is an important pretreatment technology that utilizes both physical (high temperature and pressure) and chemical (ammonia) processes to achieve effective pretreatment. Besides increasing the surface accessibility for hydrolysis, AFEX promotes cellulose decrystallization and partial hemicellulose depolymerization and reduces the lignin recalcitrance in the treated biomass. Theoretical glucose yield upon optimal enzymatic hydrolysis on AFEX-treated corn stover is approximately 98%. Furthermore, AFEX offers several unique advantages over other pretreatments, which include near complete recovery of the pretreatment chemical (ammonia), nutrient addition for microbial growth through the remaining ammonia on pretreated biomass, and not requiring a washing step during the process which facilitates high solid loading hydrolysis. This chapter provides a detailed practical procedure to perform AFEX, design the reactor, determine the mass balances, and conduct the process safely.

  16. Cobalt protoporphyrin pretreatment protects human embryonic stem cell-derived cardiomyocytes from hypoxia/reoxygenation injury in vitro and increases graft size and vascularization in vivo.

    Science.gov (United States)

    Luo, Jun; Weaver, Matthew S; Cao, Baohong; Dennis, James E; Van Biber, Benjamin; Laflamme, Michael A; Allen, Margaret D

    2014-06-01

    Human embryonic stem cell-derived cardiomyocytes (hESC-CMs) can regenerate infarcted myocardium. However, when implanted into acutely infarcted hearts, few cells survive the first week postimplant. To improve early graft survival, hESC-CMs were pretreated with cobalt protoporphyrin (CoPP), a transcriptional activator of cytoprotective heme oxygenase-1 (HO-1). When hESC-CMs were challenged with an in vitro hypoxia/reoxygenation injury, mimicking cell transplantation into an ischemic site, survival was significantly greater among cells pretreated with CoPP versus phosphate-buffered saline (PBS)-pretreated controls. Compared with PBS-pretreated cells, CoPP-pretreated hESC-CM preparations exhibited higher levels of HO-1 expression, Akt phosphorylation, and vascular endothelial growth factor production, with reduced apoptosis, and a 30% decrease in intracellular reactive oxygen species. For in vivo translation, 1 × 10(7) hESC-CMs were pretreated ex vivo with CoPP or PBS and then injected intramyocardially into rat hearts immediately following acute infarction (permanent coronary ligation). At 1 week, hESC-CM content, assessed by quantitative polymerase chain reaction for human Alu sequences, was 17-fold higher in hearts receiving CoPP- than PBS-pretreated cells. On histomorphometry, cardiomyocyte graft size was 2.6-fold larger in hearts receiving CoPP- than PBS-pretreated cells, occupying up to 12% of the ventricular area. Vascular density of host-perfused human-derived capillaries was significantly greater in grafts composed of CoPP- than PBS-pretreated cells. Taken together, these experiments demonstrate that ex vivo pretreatment of hESC-CMs with a single dose of CoPP before intramyocardial implantation more than doubled resulting graft size and improved early graft vascularization in acutely infarcted hearts. These findings open the door for delivery of these, or other, stem cells during acute interventional therapy following myocardial infarction or ischemia.

  17. Pharmacological characterization of the inhibition by moxonidine and agmatine on the cardioaccelerator sympathetic outflow in pithed rats.

    Science.gov (United States)

    Cobos-Puc, Luis E; Villalón, Carlos M; Ramírez-Rosas, Martha B; Sánchez-López, Araceli; Lozano-Cuenca, Jair; Gómez-Díaz, Benjamín; MaassenVanDenBrink, Antoinette; Centurión, David

    2009-08-15

    This study analysed the inhibition produced by the agonists moxonidine (imidazoline I(1) receptors>alpha(2)-adrenoceptors) and agmatine (endogenous ligand of imidazoline I(1)/I(2) receptors), using B-HT 933 (6-ethyl-5,6,7,8-tetrahydro-4H-oxazolo[4,5-d]azepin-2-amine dihydrochloride; alpha(2)-adrenoceptors) for comparison, on the rat cardioaccelerator sympathetic outflow. Male Wistar rats were pithed and prepared to stimulate the cardiac sympathetic outflow or to receive i.v. bolus of exogenous noradrenaline. Sympathetic stimulation or noradrenaline produced, respectively, frequency-dependent and dose-dependent tachycardic responses. I.v. continuous infusions of moxonidine (3 and 10 microg/kg min), agmatine (1000 and 3000 microg/kg min) and B-HT 933 (30 and 100 microg/kg min) inhibited the tachycardic responses to sympathetic stimulation, but not those to noradrenaline. The cardiac sympatho-inhibition by either moxonidine (3 microg/kg min) or B-HT 933 (30 microg/kg min) was not modified by i.v. injections of saline or the antagonists AGN192403 [(+/-)-2-endo-Amino-3-exo-isopropylbicyclo[2.2.1]heptane hydrochloride; 3000microg/kg; imidazoline I(1) receptors] or BU224 (2-(4,5-dihydroimidazol-2-yl)quinoline hydrochloride; 300 microg/kg; imidazoline I(2) receptors) and abolished by rauwolscine (300 microg/kg; alpha(2)-adrenoceptors). At the same doses of these compounds, the sympatho-inhibition to moxonidine (10 microg/kg min) and agmatine (1000 microg/kg min) was: (1) not modified by saline, AGN192403 or BU224; (2) partially blocked by rauwolscine or the combination of rauwolscine plus BU224; and (3) abolished by the combination of rauwolscine plus AGN192403. These results demonstrate that the cardiac sympatho-inhibition to: (1) 3 microg/kg min moxonidine or 30 microg/kg min B-HT 933 involves alpha(2)-adrenoceptors; and (2) 10 microg/kg min moxonidine or 1000 microg/kg min agmatine involves alpha(2)-adrenoceptors and imidazoline I(1) receptors.

  18. AguR is a transmembrane transcription activator of the putrescine biosynthesis operon in Lactococcus lactis, and acts in response to agmatine concentration

    NARCIS (Netherlands)

    Linares, Daniel M; Del Rio, Beatriz; Redruello, Begoña; Ladero, Victor; Martin, Ma Cruz; de Jong, Anne; Kuipers, Oscar P; Fernandez, Maria; Alvarez, Miguel A

    2015-01-01

    Dairy industry fermentative processes mostly use Lactococcus lactis as a starter. However, some dairy L. lactis strains produce putrescine - a biogenic amine that raises food safety and spoilage concerns - via the agmatine deiminase pathway (AGDI). The enzymatic activities responsible for putrescine

  19. A biphasic opioid function modulator: agmatine%双向阿片功能调节剂:胍丁胺

    Institute of Scientific and Technical Information of China (English)

    苏瑞斌; 李锦; 秦伯益

    2003-01-01

    近年研究表明某些药物尽管不能与阿片受体发生相互作用,但能对阿片药理作用产生重要的调节.特别是有些药物能对阿片功能产生双向调节作用,即增强阿片镇痛,对抗阿片耐受和躯体依赖.我们将这些不与阿片受体发生作用,但具有双向调节阿片功能的药物称之为双向阿片功能调节剂(biphasic opioid function modulator,BOFM).基于我们的研究工作,可以认定胍丁胺就是一个典型的双向阿片功能调节剂.胍丁胺本身有弱的镇痛作用,它能增强吗啡镇痛,对抗吗啡耐受和依赖;胍丁胺产生上述作用的主要机制与抑制阿片长期作用下在阿片受体信号转导系统产生的代偿性适应过程相关.%Recently it has been revealed that some agents that are not able to interact with opioid receptors play animportant role in regulating the pharmacological actions of opioids. Especially, some of them show biphasicmodulation on opioid functions, which enhance opioid analgesia, but inhibit tolerance to and substance dependenceon opioids. We would like to call these agents which do not interact with opioid receptors, but do have biphasicmodulation on opioid functions as biphasic opioid function modulator (BOFM). Mainly based on our results,agmatine is a typical BOFM. Agmatine itself was a weak analgesic which enhanced analgesic action of morphineand inhibited tolerance to and dependence on opioid. The main mechanisms of agmatine were related to inhibitionof the adaptation of opioid receptor signal transduction induced by chronic treatment of opioid.

  20. Prophylactic pretreatment of mice with hematopoietic growth factors induces expansion of primitive cell compartments and results in protection against 5-fluorouracil-induced toxicity

    NARCIS (Netherlands)

    deHaan, G; Dontje, B; Engel, C; Loeffler, M; Nijhof, W

    1996-01-01

    The aim of this study was to expand the primitive and committed hematopoietic cell compartments in vivo in order to confer resistance of the blood cell forming system against the cytotoxic, cell cycle specific drug 5-fluorouracil (5-FU). Possible chemoprotective effects of such a pretreatment could

  1. Prevalence of the lmo0036-0043 gene cluster encoding arginine deiminase and agmatine deiminase systems in Listeria monocytogenes.

    Science.gov (United States)

    Chen, Jianshun; Chen, Fan; Cheng, Changyong; Fang, Weihuan

    2013-04-01

    Arginine deiminase and agmatine deiminase systems are involved in acid tolerance, and their encoding genes form the cluster lmo0036-0043 in Listeria monocytogenes. While lmo0042 and lmo0043 were conserved in all L. monocytogenes strains, the lmo0036-0041 region of this cluster was identified in all lineages I and II, and the majority of lineage IV (83.3%) strains, but absent in all lineage III and a small fraction of lineage IV (16.7%) strains, suggesting that the presence of the complete lmo0036-0043 cluster is dependent on lineages. lmo0036-0043-complete and -deficient lineage IV strains exhibit specific ascB-dapE profiles, which might represent two subpopulations with distinct genetic characteristics.

  2. 40 CFR 417.26 - Pretreatment standards for new sources.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 28 2010-07-01 2010-07-01 true Pretreatment standards for new sources. 417.26 Section 417.26 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT... Fat Splitting Subcategory § 417.26 Pretreatment standards for new sources. Any new source subject...

  3. AguR, a Transmembrane Transcription Activator of the Putrescine Biosynthesis Operon in Lactococcus lactis, Acts in Response to the Agmatine Concentration.

    Science.gov (United States)

    Linares, Daniel M; Del Rio, Beatriz; Redruello, Begoña; Ladero, Victor; Martin, M Cruz; de Jong, Anne; Kuipers, Oscar P; Fernandez, Maria; Alvarez, Miguel A

    2015-09-01

    Dairy industry fermentative processes mostly use Lactococcus lactis as a starter. However, some dairy L. lactis strains produce putrescine, a biogenic amine that raises food safety and spoilage concerns, via the agmatine deiminase (AGDI) pathway. The enzymatic activities responsible for putrescine biosynthesis in this bacterium are encoded by the AGDI gene cluster. The role of the catabolic genes aguB, aguD, aguA, and aguC has been studied, but knowledge regarding the role of aguR (the first gene in the cluster) remains limited. In the present work, aguR was found to be a very low level constitutively expressed gene that is essential for putrescine biosynthesis and is transcribed independently of the polycistronic mRNA encoding the catabolic genes (aguBDAC). In response to agmatine, AguR acts as a transcriptional activator of the aguB promoter (PaguB), which drives the transcription of the aguBDAC operon. Inverted sequences required for PaguB activity were identified by deletion analysis. Further work indicated that AguR is a transmembrane protein which might function as a one-component signal transduction system that senses the agmatine concentration of the medium and, accordingly, regulates the transcription of the aguBDAC operon through a C-terminal cytoplasmic DNA-binding domain typically found in LuxR-like proteins.

  4. Putrescine production via the agmatine deiminase pathway increases the growth of Lactococcus lactis and causes the alkalinization of the culture medium.

    Science.gov (United States)

    del Rio, Beatriz; Linares, Daniel M; Ladero, Victor; Redruello, Begoña; Fernández, Maria; Martin, Maria Cruz; Alvarez, Miguel A

    2015-01-01

    Lactococcus lactis is the most important starter culture organism used in the dairy industry. Although L. lactis species have been awarded Qualified Presumption of Safety status by the European Food Safety Authority, and Generally Regarded as Safe status by the US Food and Drug Administration, some strains can produce the biogenic amine putrescine. One such strain is L. lactis subsp. cremoris CECT 8666 (formerly L. lactis subsp. cremoris GE2-14), which was isolated from Genestoso cheese. This strain catabolizes agmatine to putrescine via the agmatine deiminase (AGDI) pathway, which involves the production of ATP and two ammonium ions. The present work shows that the availability of agmatine and its metabolization to putrescine allows for greater bacterial growth (in a biphasic pattern) and causes the alkalinization of the culture medium in a dose-dependent manner. The construction of a mutant lacking the AGDI cluster (L. lactis CECT 8666 Δagdi) confirmed the latter's direct role in putrescine production, growth, and medium alkalinization. Alkalinization did not affect the putrescine production pattern and was not essential for increased bacterial growth.

  5. Protection against the toxicity of microcystin-LR and cylindrospermopsin in Artemia salina and Daphnia spp. by pre-treatment with cyanobacterial lipopolysaccharide (LPS).

    Science.gov (United States)

    Lindsay, J; Metcalf, J S; Codd, G A

    2006-12-15

    Purified cyanobacterial lipopolysaccharide (LPS) was not acutely toxic to three aquatic invertebrates (Artemia salina, Daphnia magna and Daphnia galeata) in immersion trials. However, pre-exposure (24 h) to 2 ngmL(-1) LPS increased the LC(50) of microcystin-LR significantly in all 3 species. Similar results were observed with A. salina pre-treated with the same concentration of cyanobacterial LPS and subsequently exposed to cylindrospermopsin, increasing the LC(50) by 8. The findings indicate the need to include exposures to defined combinations of cyanotoxins, and in defined sequences, to understand the contributions of individual cyanotoxins in accounting for cyanobacterial toxicity to invertebrates in natural aquatic environments.

  6. Mutagenic and morphologic impacts of 1.8 GHz radiofrequency radiation on human peripheral blood lymphocytes (hPBLs) and possible protective role of pre-treatment with Ginkgo biloba (EGb 761)

    Energy Technology Data Exchange (ETDEWEB)

    Esmekaya, Meric Arda, E-mail: mericarda@yahoo.com [Department of Biophysics, Gazi University, Faculty of Medicine and Gazi Non-ionizing Radiation, Protection (GNRP) Center, Ankara (Turkey); Aytekin, Ebru [Department of Medical Genetics, Gazi University Faculty of Medicine, Ankara (Turkey); Ozgur, Elcin; Gueler, Goeknur [Department of Biophysics, Gazi University, Faculty of Medicine and Gazi Non-ionizing Radiation, Protection (GNRP) Center, Ankara (Turkey); Ergun, Mehmet Ali [Department of Medical Genetics, Gazi University Faculty of Medicine, Ankara (Turkey); Oemeroglu, Suna [Department of Histology and Embryology, Gazi University, Faculty of Medicine, Ankara (Turkey); Seyhan, Nesrin [Department of Biophysics, Gazi University, Faculty of Medicine and Gazi Non-ionizing Radiation, Protection (GNRP) Center, Ankara (Turkey)

    2011-12-01

    The mutagenic and morphologic effects of 1.8 GHz Global System for Mobile Communications (GSM) modulated RF (radiofrequency) radiation alone and in combination with Ginkgo biloba (EGb 761) pre-treatment in human peripheral blood lymphocytes (hPBLs) were investigated in this study using Sister Chromatid Exchange (SCE) and electron microscopy. Cell viability was assessed with 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) reduction assay. The lymphocyte cultures were exposed to GSM modulated RF radiation at 1.8 GHz for 6, 8, 24 and 48 h with and without EGb 761. We observed morphological changes in pulse-modulated RF radiated lymphocytes. Longer exposure periods led to destruction of organelle and nucleus structures. Chromatin change and the loss of mitochondrial crista occurred in cells exposed to RF for 8 h and 24 h and were more pronounced in cells exposed for 48 h. Cytoplasmic lysis and destruction of membrane integrity of cells and nuclei were also seen in 48 h RF exposed cells. There was a significant increase (p < 0.05) in SCE frequency in RF exposed lymphocytes compared to sham controls. EGb 761 pre-treatment significantly decreased SCE from RF radiation. RF radiation also inhibited cell viability in a time dependent manner. The inhibitory effects of RF radiation on the growth of lymphoctes were marked in longer exposure periods. EGb 761 pre-treatment significantly increased cell viability in RF + EGb 761 treated groups at 8 and 24 h when compared to RF exposed groups alone. The results of our study showed that RF radiation affects cell morphology, increases SCE and inhibits cell proliferation. However, EGb 761 has a protective role against RF induced mutagenity. We concluded that RF radiation induces chromosomal damage in hPBLs but this damage may be reduced by EGb 761 pre-treatment. - Highlights: Black-Right-Pointing-Pointer RF Radiation inhibits cell proliferation. Black-Right-Pointing-Pointer RF radiation induces chromosomal damage

  7. Attenuation of the bacterial load in blood by pretreatment with granulocyte-colony-stimulating factor protects rats from fatal outcome and brain damage during Streptococcus pneumoniae meningitis

    DEFF Research Database (Denmark)

    Brandt, Christian T; Lundgren, Jens D; Lund, Søren Peter

    2004-01-01

    A model of pneumococcal meningitis in young adult rats receiving antibiotics once the infection was established was developed. The intent was to mimic clinical and histopathological features of pneumococcal meningitis in humans. The primary aim of the present study was to evaluate whether medical...... of meningitis result in reduced risks of death and brain damage. This beneficial effect is most likely achieved through improved control of the systemic disease....... postinfection did not alter the clinical or histological outcome relative to that for non-G-CSF-treated rats. The magnitude of bacteremia and pretreatment with G-CSF were found to be prognostic factors for both outcome and brain damage. In summary, elevated neutrophil levels prior to the development...

  8. Action of agmatine on tension of isolated aortic artery and its receptor mechanism in rats%胍丁胺对离体大鼠主动脉张力的影响及其受体机制

    Institute of Scientific and Technical Information of China (English)

    李清; 何瑞荣

    2001-01-01

    The effect of agmatine (Agm) on vascular tension and the underlying receptor mechanism were investigated in the isolated aortic artery of rats. The results are as follows. (1) Agm (10-7~10-2mol/L) relaxed aortic rings in a concentration-dependent manner under the condition of precontraction induced by phenylephrine (PE) at a concentration of 10-6 mol/L. (2) Either in the intact or the endothelium-denuded rings, pretreatment with NOS inhibitor NG-nitro-L-arginine methyl ester (L-NAME, 0.5 mmol/L) did not affect the vascular relaxant action of Agm, implying that the concentration-dependent vasorelaxation caused by Agm is not endothelium-dependent and NO is not involved. (3) Agm also relaxed aortic rings in a concentration-dependent manner under the condition of precontraction induced by CaCl2 at a concentration of 3 mmol/L. (4) Idazoxan (10-4 mol/L), an α2-adrenergic receptor (α2-AR) and imidazoline receptor (IR) antagonist, abolished the Agm-induced vasorelaxation completely under the condition of CaCl2-induced precontraction. (5) Yohimbine (10-4 mol/L), a selective α2-AR antagonist, could partially block the vascular relaxant action of Agm. It is suggested that the vascular relaxant effect of Agm on the rat aortic artery may be mediated by α2-AR and IR.%采用离体血管环灌流方法, 观察了胍丁胺(agmatine, Agm)对大鼠胸主动脉张力的影响, 并探讨其受体机制。实验结果如下: (1) 在苯肾上腺素(PE, 10-6 mol/L)引起血管预收缩的基础上, Agm (10-7~10-2 mol/L) 剂量依赖性地舒张大鼠胸主动脉。(2) 上述舒张反应在去除内皮和应用NOS 抑制剂NG-nitro-L-arginine methyl ester (L-NAME, 0.5 mmol/L) 后依然存在, 提示Agm的舒血管作用为非内皮依赖性, 并无NO的参与。(3) 在高Ca2+ (3 mmol/L)引起血管预收缩的基础上, Agm也可剂量依赖性地舒张大鼠主动脉。(4)预先应用α2-肾上腺素能受体(α2-adrenergic receptor, α2-AR)和

  9. Protection by low-dose γ radiation on doxorubicin-induced nephropathy in rats pretreated with curcumin, green tea, garlic or l-carnitine

    Directory of Open Access Journals (Sweden)

    Rasha R. Radwan

    2012-12-01

    Full Text Available The protective potentials of a single exposure to 0.3 Gy of γ radiation alone or with previous treatment with certain natural products with antioxidants activity, namely curcumin (50 mg/kg, i.p., green tea (300 mg/kg, p.o., garlic (100 mg/kg, p.o. or l-carnitine (40 mg/kg, i.p. against doxorubicin (DOX-induced nephropathy in rats were studied. Natural products were administered daily for 14 successive days followed by single i.p. injection of DOX (5 mg/kg. Rats were subjected to whole body γ radiation, 1 day before DOX administration. Serum levels of creatinine, urea, uric acid, low density lipoprotein (LDL-C, high density lipoprotein (HDL-C cholesterols, total proteins and albumin as well as renal concentrations of reduced glutathione (GSH, thiobarbituric acid reactive substances (TBARS, nitric oxide (NO and calcium (Ca were determined. Irradiation provided significant protections against DOX-induced changes in all measured parameters, except renal Ca content. All the test natural products significantly improved radiation-induced protection against renal lipid peroxidation. l-Carnitine markedly augmented the protection toward changes in renal GSH, NO and Ca concentrations. Curcumin increased the protection toward changes in serum albumin and renal GSH and NO concentrations, while garlic increased the protection toward changes in serum LDL-C level. It could be concluded that low-dose γ radiation could provide prophylaxis against DOX-induced nephropathy which might be augmented by the use of certain natural antioxidants.

  10. Improved Protective Effect of Umbilical Cord Stem Cell Transplantation on Cisplatin-Induced Kidney Injury in Mice Pretreated with Antithymocyte Globulin

    Directory of Open Access Journals (Sweden)

    Željka Večerić-Haler

    2016-01-01

    Full Text Available Mesenchymal stem cells (MSCs are recognised as a promising tool to improve renal recovery in experimental models of cisplatin-induced acute kidney injury. However, these preclinical studies were performed on severely immunodeficient animals. Here, we investigated whether human umbilical cord derived MSC treatment could equally ameliorate acute kidney injury induced by cisplatin and prolong survival in mice with a normal immune system and those with a suppressed immune system by polyclonal antithymocyte globulin (ATG. We demonstrated that ATG pretreatment, when followed by MSC transplantation, significantly improved injured renal function parameters, as evidenced by decreased blood urea nitrogen and serum creatinine concentration, as well as improved renal morphology. This tissue restoration was also supported by increased survival of mice. The beneficial effects of ATG were associated with reduced level of inflammatory protein serum amyloid A3 and induced antioxidative expression of superoxide dismutase-1 (SOD-1, glutathione peroxidase (GPx, and hem oxygenase-1 (HO-1. Infused MSCs became localised predominantly in peritubular areas and acted to reduce renal cell death. In conclusion, these results show that ATG diminished in situ inflammation and oxidative stress associated with cisplatin-induced acute kidney injury, the effects that may provide more favourable microenvironment for MSC action, with consequential synergistic improvements in renal injury and animal survival as compared to MSC treatment alone.

  11. 点按瘢痕灸预处理对大鼠脑缺血再灌注损伤的保护作用%Protective effect of pretreatment with scarring moxibustion in rats with cerebral ischemia-reperfusion injury

    Institute of Scientific and Technical Information of China (English)

    赵华; 赵百孝; 徐佳; 徐鸣曙; 刘智艳

    2012-01-01

    Objective To investigate the protective effect of pretreatment with scarring moxibustion with incense stick in rats with cerebral ischemia-reperfusion injury. Methods SD rats ( n = 40) were randomly divided into control group, model group, pretreatment group with scarring moxibustion with moxa cone ( moxa cone group) and pretreatment group with scarring moxibustion with incense stick (incense stick group). The rat model of middle cerebral artery occlusion (MCAO) and reperfusion was established by using thread approach. The moxa cone group and incense stick group were given the pretreatment of scarring moxibustion with moxa cone or incense stick on Zusanli ( ST36) 3 days before ischemia-reperfusion. The rats were sacrificed after ischemia for 3 hours and reperfusion for 24 hours. The control group and model group were not given the pretreatment. The content changes of superoxide dismutase (SOD), malondialdehyde (MDA) , nitric oxide (NO) and lactic acid (LD) were observed in all groups. Results The content of NO, LD and MDA decreased significantly, and content of SOD increased significantly in incense stick group compared with model group ( P 0. 05 ). Conclusion The pretreatment of scarring moxibustion with incense stick and that with moxa cone can promote antioxidation in cells, reduce neurotoxicity mediated by NO and improve the energy metabolism in brain cells, and have significant protective effect in rats with cerebral ischemia - reperfusion. The effect of pretreatment of scarring moxibustion with incense stick is better than that of pretreatment of scarring moxibustion with moxa cone.%目的 探讨线香点按瘢痕灸预处理对脑缺血再灌注损伤的保护作用.方法 SD大鼠40只,随机分为对照组、模型组、艾炷灸组、线香点按灸组.采用线栓法制备大鼠大脑中动脉闭塞(MCAO)及再灌注模型,艾炷灸组、线香点按灸组于缺血再灌注前3d以艾炷、线香点按瘢痕灸足三里预处理,缺血3h再灌注24h后

  12. Effects of laser pretreatment on cells of broad bean in UV-B-induced damage protection%激光预处理可保护蚕豆细胞免受UV-B辐射的损伤

    Institute of Scientific and Technical Information of China (English)

    齐智; 岳明; 王勋陵

    2000-01-01

    The embryos of broad bean (Vicia faba L.) were irradiated for 5 min by a He-Ne laser (632.8 nm,1.63 J·mm-2) or for 1 min by a CO2 laser (1,060 nm,2.53 J·mm-2).Afterwards they were cultivated in Petri dish in the constant temperature incubator in Knop until the length of epicotyl of broad bean was perhaply 3 cm that could be treated by ultraviolet-B (UV-B) radiation.The epicotyl of broad bean was irradiated for 7 h by 1.02,3.03,4.52 kJ·m-2 UV-B respectively in the ambient condition of 70 μmol·m-2·s-1 photosynthetically active radiation (PAR) in the growth cabinet.According to the changes of content of MDA,ascorbate acid (AsA) and UV-B absorbing compounds (absorbance at 300 nm),the effects of protecting of laser to the epicotyl of broad bean from UV-B radiation were tested.The results showed that laser pretreatment on the embryos could enhance the resistance of UV-B stress in epicotyl.Comparing with the control (without UV-B or laser radiation) and UV-B radiation alone,the MDA content was decreased significantly while AsA content was increased in the condition of laser pretreatment.It was also found that laser pretreatment alone could improve the content of UV-B absorbing compounds.If laser pretreatment followed UV-B radiation,the content of UV-B absorbing compounds was improved higher than laser treatment and UV-B treatment respectively.We suppose that laser pretreatment could enhance stress resistance in plant by a pathway of increasing the content of AsA and UV-B absorbing compounds while decreasing the MDA concentration.%当蚕豆的胚被He-Ne激光(632.8 nm,1.63 J·mm-2)照射5 min或被CO2激光(1060 nm,2.53 J·mm-2) 照射1 min后,将其置入Knop营养液中进行恒温培养.当蚕豆的上胚轴长到大约3 cm时,在光背景(PAR)为70 μmol·m-2·s-1条件下,分别用1.02、3.03、4.52 kJ·m-2的UV-B 辐射蚕豆的上胚轴7 h.根据蚕豆丙二醛(MDA)、抗坏血酸(AsA)和UV-B吸收物的含量变化,来测试激光对UV-B照射蚕豆的上

  13. New insight into the transcarbamylase family: the structure of putrescine transcarbamylase, a key catalyst for fermentative utilization of agmatine.

    Science.gov (United States)

    Polo, Luis Mariano; Gil-Ortiz, Fernando; Cantín, Angel; Rubio, Vicente

    2012-01-01

    Transcarbamylases reversibly transfer a carbamyl group from carbamylphosphate (CP) to an amine. Although aspartate transcarbamylase and ornithine transcarbamylase (OTC) are well characterized, little was known about putrescine transcarbamylase (PTC), the enzyme that generates CP for ATP production in the fermentative catabolism of agmatine. We demonstrate that PTC (from Enterococcus faecalis), in addition to using putrescine, can utilize L-ornithine as a poor substrate. Crystal structures at 2.5 Å and 2.0 Å resolutions of PTC bound to its respective bisubstrate analog inhibitors for putrescine and ornithine use, N-(phosphonoacetyl)-putrescine and δ-N-(phosphonoacetyl)-L-ornithine, shed light on PTC preference for putrescine. Except for a highly prominent C-terminal helix that projects away and embraces an adjacent subunit, PTC closely resembles OTCs, suggesting recent divergence of the two enzymes. Since differences between the respective 230 and SMG loops of PTC and OTC appeared to account for the differential preference of these enzymes for putrescine and ornithine, we engineered the 230-loop of PTC to make it to resemble the SMG loop of OTCs, increasing the activity with ornithine and greatly decreasing the activity with putrescine. We also examined the role of the C-terminal helix that appears a constant and exclusive PTC trait. The enzyme lacking this helix remained active but the PTC trimer stability appeared decreased, since some of the enzyme eluted as monomers from a gel filtration column. In addition, truncated PTC tended to aggregate to hexamers, as shown both chromatographically and by X-ray crystallography. Therefore, the extra C-terminal helix plays a dual role: it stabilizes the PTC trimer and, by shielding helix 1 of an adjacent subunit, it prevents the supratrimeric oligomerizations of obscure significance observed with some OTCs. Guided by the structural data we identify signature traits that permit easy and unambiguous annotation of PTC

  14. Alpha-2 adrenoceptors and imidazoline receptors in cardiomyocytes mediate counterbalancing effect of agmatine on NO synthesis and intracellular calcium handling.

    Science.gov (United States)

    Maltsev, Alexander V; Kokoz, Yuri M; Evdokimovskii, Edward V; Pimenov, Oleg Y; Reyes, Santiago; Alekseev, Alexey E

    2014-03-01

    Evidence suggests that intracellular Ca(2+) levels and contractility of cardiomyocytes can be modulated by targeting receptors other than already identified adrenergic or non-adrenergic sarcolemmal receptors. This study uncovers the presence in myocardial cells of adrenergic α2 (α2-AR) and imidazoline I1 (I1R) receptors. In isolated left ventricular myocytes generating stationary spontaneous Ca(2+) transients in the absence of triggered action potentials, the prototypic agonist of both receptors agmatine can activate corresponding signaling cascades with opposing outcomes on nitric oxide (NO) synthesis and intracellular Ca(2+) handling. Specifically, activation of α2-AR signaling through PI3 kinase and Akt/protein kinase B stimulates NO production and abolishes Ca(2+) transients, while targeting of I1R signaling via phosphatidylcholine-specific phospholipase C (PC-PLC) and protein kinase C (PKC) suppresses NO synthesis and elevates averaged intracellular Ca(2+). We identified that endothelial NO synthase (eNOS) is a major effector for both signaling cascades. According to the established eNOS transitions between active (Akt-dependent) and inactive (PKC-dependent) conformations, we suggest that balance between α2-AR and I1R signaling pathways sets eNOS activity, which by defining operational states of myocellular sarcoplasmic reticulum Ca(2+)-ATPase (SERCA) can adjust Ca(2+) re-uptake and thereby cardiac inotropy. These results indicate that the conventional catalog of cardiomyocyte sarcolemmal receptors should be expanded by the α2-AR and I1R populations, unveiling previously unrecognized targets for endogenous ligands as well as for existing and potential pharmacological agents in cardiovascular medicine.

  15. New insight into the transcarbamylase family: the structure of putrescine transcarbamylase, a key catalyst for fermentative utilization of agmatine.

    Directory of Open Access Journals (Sweden)

    Luis Mariano Polo

    Full Text Available Transcarbamylases reversibly transfer a carbamyl group from carbamylphosphate (CP to an amine. Although aspartate transcarbamylase and ornithine transcarbamylase (OTC are well characterized, little was known about putrescine transcarbamylase (PTC, the enzyme that generates CP for ATP production in the fermentative catabolism of agmatine. We demonstrate that PTC (from Enterococcus faecalis, in addition to using putrescine, can utilize L-ornithine as a poor substrate. Crystal structures at 2.5 Å and 2.0 Å resolutions of PTC bound to its respective bisubstrate analog inhibitors for putrescine and ornithine use, N-(phosphonoacetyl-putrescine and δ-N-(phosphonoacetyl-L-ornithine, shed light on PTC preference for putrescine. Except for a highly prominent C-terminal helix that projects away and embraces an adjacent subunit, PTC closely resembles OTCs, suggesting recent divergence of the two enzymes. Since differences between the respective 230 and SMG loops of PTC and OTC appeared to account for the differential preference of these enzymes for putrescine and ornithine, we engineered the 230-loop of PTC to make it to resemble the SMG loop of OTCs, increasing the activity with ornithine and greatly decreasing the activity with putrescine. We also examined the role of the C-terminal helix that appears a constant and exclusive PTC trait. The enzyme lacking this helix remained active but the PTC trimer stability appeared decreased, since some of the enzyme eluted as monomers from a gel filtration column. In addition, truncated PTC tended to aggregate to hexamers, as shown both chromatographically and by X-ray crystallography. Therefore, the extra C-terminal helix plays a dual role: it stabilizes the PTC trimer and, by shielding helix 1 of an adjacent subunit, it prevents the supratrimeric oligomerizations of obscure significance observed with some OTCs. Guided by the structural data we identify signature traits that permit easy and unambiguous annotation

  16. Attenuation of insulin resistance in rats by agmatine: role of SREBP-1c, mTOR and GLUT-2.

    Science.gov (United States)

    Sharawy, Maha H; El-Awady, Mohammed S; Megahed, Nirmeen; Gameil, Nariman M

    2016-01-01

    Insulin resistance is a serious health condition worldwide; however, its exact mechanisms are still unclear. This study investigates agmatine (AGM; an endogenous metabolite of L-arginine) effects on insulin resistance induced by high fructose diet (HFD) in rats and the possible involved mechanisms. Sprague Dawley rats were fed 60% HFD for 12 weeks, and AGM (10 mg/kg/day, orally) was given from week 9 to 12. AGM significantly reduced HFD-induced elevation in fasting insulin level, homeostasis model assessment of insulin resistance (HOMA-IR) index and liver glycogen content from 3.44-, 3.62- and 2.07- to 2.59-, 2.78- and 1.3-fold, respectively, compared to the control group, while it increased HFD-induced reduction in glucose tolerance. Additionally, AGM significantly decreased HFD-induced elevation in serum triglycerides, low density lipoprotein cholesterol and very low density lipoprotein cholesterol levels from 3.18-, 2.97- and 4.75- to 1.25-, 1.25- and 1.07-fold, respectively, compared to control group. Conversely, AGM had no significant effect on HFD-induced changes in fasting glucose, glycosylated hemoglobin, insulin tolerance and high density lipoprotein cholesterol. Furthermore, AGM significantly reduced HFD-induced elevation in mRNA expression of glucose transporter type-2 (GLUT-2), mammalian target of rapamycin (mTOR) and sterol regulatory element-binding protein-1c (SREBP-1c) without affecting that of peroxisome proliferator-activated receptor-alpha (PPAR-α) in the liver. Additionally, AGM enhanced ACh-induced aortic relaxation and attenuated liver steatosis induced by HFD. In conclusion, AGM may have a therapeutic potential in insulin resistance through suppressing SREBP-1c, mTOR and GLUT-2 in liver.

  17. Potent In Vitro Protection Against PM₂.₅-Caused ROS Generation and Vascular Permeability by Long-Term Pretreatment with Ganoderma tsugae.

    Science.gov (United States)

    Tseng, Chia-Yi; Chung, Meng-Chi; Wang, Jhih-Syuan; Chang, Yu-Jung; Chang, Jing-Fen; Lin, Chin-Hung; Hseu, Ruey-Shyang; Chao, Ming-Wei

    2016-01-01

    Epidemiological studies show increased particulate matter (PM[Formula: see text]) particles in ambient air are correlated with increased myocardial infarctions. Given the close association of capillaries and alveoli, the dysfunction is caused when inhaled PM[Formula: see text] particles come in close proximity to capillary endothelial cells. We previously suggested that the inhalation of PM[Formula: see text] diesel exhaust particles (DEP) induces oxidative stress and upregulates the Nrf2/HO-1 pathway, inducing vascular permeability factor VEGFA secretion, which results in cell-cell adherens junction disruption and PM[Formula: see text] transmigratation into circulation. Here, we minimized the level that PM[Formula: see text] traveled in the bloodstream by pre-supplementing with a traditional Chinese medicine (TCM) Ganoderma tsugae DMSO extract (GTDE) prior to PM[Formula: see text] exposure. Our results show that PM[Formula: see text] caused alterations in enzyme activities and cellular anti-oxidant balance. We found decreased glutathione levels, a reduced cellular redox ratio, increased ROS generation and cytotoxicity in the cellular fractions. The oxidative stress caused DNA damage and apoptosis, likely causing downstream molecular events that trigger vasculature permeabilization and, eventually, cardiovascular disorders. Our results show long-term GTDE treatment increased endogenous glutathione level, while PM[Formula: see text]-reduced glutathione levels and the cellular redox ratio. GTDE was protective against the genotoxic and apoptotic effects initiated by PM[Formula: see text] oxidative stress. Vascular permeability revealed that PM[Formula: see text] only accumulated on the surface of cells after GTDE treatment; no penetration was detected. After two weeks of GTDE treatment, VEGFA secretion was significantly reduced in human umbilical vein endothelial cells (HUVEC) and endothelial cell migration was blocked. Our results suggest GTDE prevents PM

  18. Protective

    Directory of Open Access Journals (Sweden)

    Wessam M. Abdel-Wahab

    2013-10-01

    Full Text Available Many active ingredients extracted from herbal and medicinal plants are extensively studied for their beneficial effects. Antioxidant activity and free radical scavenging properties of thymoquinone (TQ have been reported. The present study evaluated the possible protective effects of TQ against the toxicity and oxidative stress of sodium fluoride (NaF in the liver of rats. Rats were divided into four groups, the first group served as the control group and was administered distilled water whereas the NaF group received NaF orally at a dose of 10 mg/kg for 4 weeks, TQ group was administered TQ orally at a dose of 10 mg/kg for 5 weeks, and the NaF-TQ group was first given TQ for 1 week and was secondly administered 10 mg/kg/day NaF in association with 10 mg/kg TQ for 4 weeks. Rats intoxicated with NaF showed a significant increase in lipid peroxidation whereas the level of reduced glutathione (GSH and the activity of superoxide dismutase (SOD, catalase (CAT, glutathione S-transferase (GST and glutathione peroxidase (GPx were reduced in hepatic tissues. The proper functioning of the liver was also disrupted as indicated by alterations in the measured liver function indices and biochemical parameters. TQ supplementation counteracted the NaF-induced hepatotoxicity probably due to its strong antioxidant activity. In conclusion, the results obtained clearly indicated the role of oxidative stress in the induction of NaF toxicity and suggested hepatoprotective effects of TQ against the toxicity of fluoride compounds.

  19. GREET Pretreatment Module

    Energy Technology Data Exchange (ETDEWEB)

    Adom, Felix K.; Dunn, Jennifer B.; Han, Jeongwoo

    2014-09-01

    A wide range of biofuels and biochemicals can be produced from biomass via different pretreatment technologies that yield sugars. This report documents the material and energy flows that occur when fermentable sugars from four lignocellulosic feedstocks (corn stover, miscanthus, switchgrass, and poplar) are produced via dilute acid pretreatment and ammonia fiber expansion. These flows are documented for inclusion in the pretreatment module of the Greenhouses Gases, Regulated Emissions, and Energy Use in Transportation (GREET) model. Process simulations of each pretreatment technology were developed in Aspen Plus. Material and energy consumption data from Aspen Plus were then compiled in the GREET pretreatment module. The module estimates the cradle-to-gate fossil energy consumption (FEC) and greenhouse gas (GHG) emissions associated with producing fermentable sugars. This report documents the data and methodology used to develop this module and the cradle-to-gate FEC and GHG emissions that result from producing fermentable sugars.

  20. Solids Control in Sludge Pretreatment

    Energy Technology Data Exchange (ETDEWEB)

    Beahm, E.C., Weber, C.F., Hunt, R.D., Dillow, T.A.

    1997-12-31

    Sludge pretreatment will likely involve washing, followed by caustic or acidic leaching and washing of sludge residues after leaching. The principal goal of pretreatment is to obtain a low-volume high-activity waste stream and a high-volume low-activity waste stream. Also, some waste constituents such as chromium and phosphate can be included in glass formulations only at very low concentrations; therefore, it is desirable to remove them from high-level waste streams. Two aspects of sludge treatment and subsequent separations should be well delineated and predictable: (1) the distribution of chemical species between aqueous solutions and solids and (2) potential problems due to chemical interactions that could result in process difficulties or safety concerns.Before any treatment technology is adopted, it must be demonstrated that the process can be carried out as planned. Three pretreatment methods were considered in the Tri-Party (Washington State Ecology, U.S. Environmental Protection Agency, and U.S. Department of Energy) negotiations: (1) sludge washing with corrosion- inhibiting water, (2) Enhanced Sludge Washing, and (3)acidic dissolution with separations processes. Enhanced Sludge Washing is the baseline process. In Enhanced Sludge Washing, sludge is first washed with corrosion-inhibiting water; it is then leached with caustic (sodium hydroxide solution) and washed again with corrosion- inhibiting water. The initial concern is whether a pretreatment technique is effective in separating sludge components. This can be evaluated by bench-scale tests with sludge specimens from underground storage tanks. The results give data on the distribution of important species such as aluminum, phosphate, and radionuclides between wash and leach solutions and solid sludge residues.

  1. 40 CFR 415.444 - Pretreatment standards for existing sources (PSES).

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 28 2010-07-01 2010-07-01 true Pretreatment standards for existing sources (PSES). 415.444 Section 415.444 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Monoxide Production Subcategory § 415.444 Pretreatment standards for existing sources (PSES). Except...

  2. 40 CFR 444.16 - Pretreatment standards for existing sources (PSES).

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 29 2010-07-01 2010-07-01 false Pretreatment standards for existing sources (PSES). 444.16 Section 444.16 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED... Combustor Subcategory § 444.16 Pretreatment standards for existing sources (PSES). Except as provided in...

  3. 40 CFR 415.666 - Pretreatment standards for new sources (PSNS).

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 28 2010-07-01 2010-07-01 true Pretreatment standards for new sources (PSNS). 415.666 Section 415.666 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED... Production Subcategory § 415.666 Pretreatment standards for new sources (PSNS). Except as provided in 40...

  4. 40 CFR 426.64 - Pretreatment standards for existing sources.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 29 2010-07-01 2010-07-01 false Pretreatment standards for existing sources. 426.64 Section 426.64 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS GLASS MANUFACTURING POINT SOURCE CATEGORY Automotive Glass...

  5. 40 CFR 426.66 - Pretreatment standards for new sources.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 29 2010-07-01 2010-07-01 false Pretreatment standards for new sources. 426.66 Section 426.66 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS GLASS MANUFACTURING POINT SOURCE CATEGORY Automotive Glass Tempering...

  6. 40 CFR 428.66 - Pretreatment standards for new sources.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 29 2010-07-01 2010-07-01 false Pretreatment standards for new sources. 428.66 Section 428.66 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS RUBBER MANUFACTURING POINT SOURCE CATEGORY Medium-Sized General Molded,...

  7. 40 CFR 421.256 - Pretreatment standards for new sources.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 28 2010-07-01 2010-07-01 true Pretreatment standards for new sources. 421.256 Section 421.256 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS NONFERROUS METALS MANUFACTURING POINT SOURCE CATEGORY Primary Precious Metals...

  8. 40 CFR 421.275 - Pretreatment standards for existing sources.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 28 2010-07-01 2010-07-01 true Pretreatment standards for existing sources. 421.275 Section 421.275 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS NONFERROUS METALS MANUFACTURING POINT SOURCE CATEGORY Primary Rare...

  9. 40 CFR 421.266 - Pretreatment standards for new sources.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 28 2010-07-01 2010-07-01 true Pretreatment standards for new sources. 421.266 Section 421.266 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS NONFERROUS METALS MANUFACTURING POINT SOURCE CATEGORY Secondary Precious...

  10. 40 CFR 421.276 - Pretreatment standards for new sources.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 28 2010-07-01 2010-07-01 true Pretreatment standards for new sources. 421.276 Section 421.276 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS NONFERROUS METALS MANUFACTURING POINT SOURCE CATEGORY Primary Rare Earth...

  11. 40 CFR 421.265 - Pretreatment standards for existing sources.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 28 2010-07-01 2010-07-01 true Pretreatment standards for existing sources. 421.265 Section 421.265 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS NONFERROUS METALS MANUFACTURING POINT SOURCE CATEGORY Secondary...

  12. Zinc-induced protection against cadmium

    Energy Technology Data Exchange (ETDEWEB)

    Early, J.L.; Schnell, R.C.

    1978-02-01

    Pretreatment of male rats with cadmium acetate potentiates the duration of hexobarbital hypnosis and inhibits the rate of hepatic microsomal drug metabolism. Pretreatment of rats with zinc acetate protects against these alterations in drug action elicited by cadmium.

  13. 内毒素预处理对内毒素血症大鼠肝损伤的保护作用%Protective effects of endotoxin pretreatment on hepatic tissue in rats with endotoxemia

    Institute of Scientific and Technical Information of China (English)

    陈华文; 祝伟; 李树生; 杨光田

    2009-01-01

    ),LPS pretreated group(P,n=24).Each group was divid-ed into four subgroups:saline control and lipopolysaccharide (LPS)-treated 2 h,4 h,6 h,12 h groups and LPS-pretreated 2 h,4 h,6 h,12 h groups.Rats in group P were first administered with introperitoneal injection of 0.25 mg/kg LPS,and after 24 hours,the rats were injected with 0.5 mg/kg LPS.Rats in group N and group L received with an equivalent amount of saline.After 72 hours,rats in group L and group P were intravenonsly injected with 10 mg/kg LPS,and rats in group N received with an equivalent amount of saline.Six rats were killed at 2,4,6 and 12 hours after injection of LPS in group L and P.The hvers were removed for detecting Toll like receptor-4 (TLR-4),nuclear factor-кB(NF-кB),tumor Necrosis Factor-apha(TNF-α)and malondialdehyde(MDA).The blood was drawn for detecting Alamine aminotmnsferose (ALT) and Aspartate aminotransferose (AST).The patho-logical changes of liver were also examined.Software SPSS13.0 was utilized to do ANOVA for statistical analysis.Results The rats exposed to LPS alone demonstrated an increase in TLR-4.NF-кB and TNF-α activity of the liver tissue.Incontrast.the rats exporsed 10 LPS prelreatment exhibited a significant decrease in TLT-4,NF-кB and TNF-α activity.The contents of TLR-4,NF-кB and TNF-α of LPS-treated 4 h groupwere,(38.76±0.67),170.82 ±31.40),293.16±49.49)and(6.263±0.351),significantly higher than those of the saline control group.The administration of endotoxin pretreatment reduced the indexes to(22.35±1.35),(135.55±26.44)and(234.23±44.96),respectively(P<0.05).Conclusions TLR-4,NF-кB and TNF-α take part in the progress of hepatic injury in rats with endotoxemia.Endotoxin pretreatment can eliminate hepatic injury and protect the hepatic tissue by downmgulating the levels of TLR-4.NF-кB and TNF-α.

  14. GREET Pretreatment Module

    Energy Technology Data Exchange (ETDEWEB)

    Adom, Felix K. [Argonne National Lab. (ANL), Argonne, IL (United States). Energy Systems Division; Dunn, Jennifer B. [Argonne National Lab. (ANL), Argonne, IL (United States). Energy Systems Division; Han, Jeongwoo [Argonne National Lab. (ANL), Argonne, IL (United States). Energy Systems Division

    2014-09-01

    A wide range of biofuels and biochemicals can be produced from cellulosic biomass via different pretreatment technologies that yield sugars. Process simulations of dilute acid and ammonia fiber expansion pretreatment processes and subsequent hydrolysis were developed in Aspen Plus for four lignocellulosic feedstocks (corn stover, miscanthus, switchgrass, and poplar). This processing yields sugars that can be subsequently converted to biofuels or biochemical. Material and energy consumption data from Aspen Plus were then compiled in a new Greenhouses Gases, Regulated Emissions, and Energy Use in Transportation (GREETTM) pretreatment module. The module estimates the cradle-to-gate fossil energy consumption (FEC) and greenhouse gas (GHG) emissions associated with producing fermentable sugars. This report documents the data and methodology used to develop this module and the cradle-to-gate FEC and GHG emissions that result from producing fermentable sugars.

  15. Pretreatment methods for bioethanol production.

    Science.gov (United States)

    Xu, Zhaoyang; Huang, Fang

    2014-09-01

    Lignocellulosic biomass, such as wood, grass, agricultural, and forest residues, are potential resources for the production of bioethanol. The current biochemical process of converting biomass to bioethanol typically consists of three main steps: pretreatment, enzymatic hydrolysis, and fermentation. For this process, pretreatment is probably the most crucial step since it has a large impact on the efficiency of the overall bioconversion. The aim of pretreatment is to disrupt recalcitrant structures of cellulosic biomass to make cellulose more accessible to the enzymes that convert carbohydrate polymers into fermentable sugars. This paper reviews several leading acidic, neutral, and alkaline pretreatments technologies. Different pretreatment methods, including dilute acid pretreatment (DAP), steam explosion pretreatment (SEP), organosolv, liquid hot water (LHW), ammonia fiber expansion (AFEX), soaking in aqueous ammonia (SAA), sodium hydroxide/lime pretreatments, and ozonolysis are intensively introduced and discussed. In this minireview, the key points are focused on the structural changes primarily in cellulose, hemicellulose, and lignin during the above leading pretreatment technologies.

  16. PRETREATING THORIUM FOR ELECTROPLATING

    Science.gov (United States)

    Beach, J.G.; Schaer, G.R.

    1959-07-28

    A method is presented for pretreating a thorium surface prior to electroplating the surface. The pretreatment steps of the invention comprise cleaning by vapor blasting the surface, anodically pickling in a 5 to 15% by volume aqueous hydrochloric acid bath with a current of 125 to 250 amp/sq ft for 3 to 5 min at room temperature, chemically pickling the surface in a 5 to 15% by volume of aqueous sulfuric acid for 3 to 5 min at room temperature, and rinsing the surface with water.

  17. 40 CFR 444.18 - Pretreatment standards for new sources (PSNS).

    Science.gov (United States)

    2010-07-01

    ... (PSNS). 444.18 Section 444.18 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED... Combustor Subcategory § 444.18 Pretreatment standards for new sources (PSNS). Except as provided in 40 CFR... § 444.16....

  18. Advances in aluminum pretreatment

    Energy Technology Data Exchange (ETDEWEB)

    Sudour, Michel; Maintier, Philippe [PPG Industries France, 3 Z.A.E. Les Dix Muids, B.P. 89, F-59583 Marly (France); Simpson, Mark [PPG Industries Inc., 1200 Piedmont Troy, Michigan 48083 (United States); Quaglia, Paolo [PPG Industries Italia, Via Garavelli 21, I-15028 Quattordio (Italy)

    2004-07-01

    As automotive manufacturers continue to look for ways to reduce vehicle weight, aluminum is finding more utility as a body panel component. The substitution of cold-rolled steel and zinc-coated substrates with aluminum has led to new challenges in vehicle pretreatment. As a result, changes to traditional pretreatment chemistries and operating practices are necessary in order to produce an acceptable coating on aluminum body panels. These changes result in increased sludging and other undesirable characteristics. In addition to the chemistry changes, there are also process-related problems to consider. Many existing automotive pretreatment lines simply were not designed to handle aluminum and its increased demands on filtration and circulation equipment. To retrofit such a system is capital intensive and in addition to requiring a significant amount of downtime, may not be totally effective. Thus, the complexities of pre-treating aluminum body panels have actually had a negative effect on efforts to introduce more aluminum into new vehicle design programs. Recent research into ways of reducing the negative effects has led to a new understanding of the nature of zinc phosphate bath -aluminum interactions. Many of the issues associated with the pretreatment of aluminum have been identified and can be mitigated with only minor changes to the zinc phosphate bath chemistry. The use of low levels of soluble Fe ions, together with free fluoride, has been shown to dramatically improve the efficiency of a zinc phosphate system processing aluminum. Appearance of zinc phosphate coatings, coating weights and sludge are all benefited by this chemistry change. (authors)

  19. PROJECT W-551 INTERIM PRETREATMENT SYSTEM PRECONCEPTUAL CANDIDATE TECHNOLOGY DESCRIPTIONS

    Energy Technology Data Exchange (ETDEWEB)

    MAY TH

    2008-08-12

    The Office of River Protection (ORP) has authorized a study to recommend and select options for interim pretreatment of tank waste and support Waste Treatment Plant (WTP) low activity waste (LAW) operations prior to startup of all the WTP facilities. The Interim Pretreatment System (IPS) is to be a moderately sized system which separates entrained solids and 137Cs from tank waste for an interim time period while WTP high level waste vitrification and pretreatment facilities are completed. This study's objective is to prepare pre-conceptual technology descriptions that expand the technical detail for selected solid and cesium separation technologies. This revision includes information on additional feed tanks.

  20. Nonhazardous Urine Pretreatment Method

    Science.gov (United States)

    Akse, James R.; Holtsnider, John T.

    2012-01-01

    A method combines solid phase acidification with two non-toxic biocides to prevent ammonia volatilization and microbial proliferation. The safe, non-oxidizing biocide combination consists of a quaternary amine and a food preservative. This combination has exhibited excellent stabilization of both acidified and unacidified urine. During pretreatment tests, composite urine collected from donors was challenged with a microorganism known to proliferate in urine, and then was processed using the nonhazardous urine pre-treatment method. The challenge microorganisms included Escherichia coli, a common gram-negative bacteria; Enterococcus faecalis, a ureolytic gram-positive bacteria; Candida albicans, a yeast commonly found in urine; and Aspergillus niger, a problematic mold that resists urine pre-treatment. Urine processed in this manner remained microbially stable for over 57 days. Such effective urine stabilization was achieved using non-toxic, non-oxidizing biocides at higher pH (3.6 to 5.8) than previous methods in use or projected for use aboard the International Space Station (ISS). ISS urine pretreatment methods employ strong oxidants including ozone and hexavalent chromium (Cr(VI)), a carcinogenic material, under very acidic conditions (pH = 1.8 to 2.4). The method described here offers a much more benign chemical environment than previous pretreatment methods, and will lower equivalent system mass (ESM) by reducing containment volume and mass, system complexity, and crew time needed to handle pre-treatment chemicals. The biocides, being non-oxidizing, minimize the potential for chemical reactions with urine constituents to produce volatile, airborne contaminants such as cyanogen chloride. Additionally, the biocides are active under significantly less acidic conditions than those used in the current system, thereby reducing the degree of required acidification. A simple flow-through solid phase acidification (SPA) bed is employed to overcome the natural buffering

  1. Biomass shock pretreatment

    Science.gov (United States)

    Holtzapple, Mark T.; Madison, Maxine Jones; Ramirez, Rocio Sierra; Deimund, Mark A.; Falls, Matthew; Dunkelman, John J.

    2014-07-01

    Methods and apparatus for treating biomass that may include introducing a biomass to a chamber; exposing the biomass in the chamber to a shock event to produce a shocked biomass; and transferring the shocked biomass from the chamber. In some aspects, the method may include pretreating the biomass with a chemical before introducing the biomass to the chamber and/or after transferring shocked biomass from the chamber.

  2. Lmo0036, an ornithine and putrescine carbamoyltransferase in Listeria monocytogenes, participates in arginine deiminase and agmatine deiminase pathways and mediates acid tolerance.

    Science.gov (United States)

    Chen, Jianshun; Cheng, Changyong; Xia, Ye; Zhao, Hanxin; Fang, Chun; Shan, Ying; Wu, Beibei; Fang, Weihuan

    2011-11-01

    Listeria monocytogenes is a foodborne pathogen causing listeriosis. Acid is one of the stresses that foodborne pathogens encounter most frequently. The ability to survive and proliferate in acidic environments is a prerequisite for infection. However, there is limited knowledge about the molecular basis of adaptation of L. monocytogenes to acid. Arginine deiminase (ADI) and agmatine deiminase (AgDI) systems are implicated in bacterial tolerance to acidic environments. Homologues of ADI and AgDI systems have been found in L. monocytogenes lineages I and II strains. Sequence analysis indicated that lmo0036 encodes a putative carbamoyltransferase containing conserved motifs and residues important for substrate binding. Lmo0036 acted as an ornithine carbamoyltransferase and putrescine carbamoyltransferase, representing the first example, to our knowledge, that catalyses reversible ornithine and putrescine carbamoyltransfer reactions. Catabolic ornithine and putrescine carbamoyltransfer reactions constitute the second step of ADI and AgDI pathways. However, the equilibrium of in vitro carbamoyltransfer reactions was overwhelmingly towards the anabolic direction, suggesting that catabolic carbamoyltransferase was probably the limiting step of the pathways. lmo0036 was induced at the transcriptional level when L. monocytogenes was subjected to low-pH stress. Its expression product in Escherichia coli exhibited higher catabolic carbamoyltransfer activities under acidic conditions. Consistently, absence of this enzyme impaired the growth of Listeria under mild acidic conditions (pH 4.8) and reduced its survival in synthetic human gastric fluid (pH 2.5), and corresponded to a loss in ammonia production, indicating that Lmo0036 was responsible for acid tolerance at both sublethal and lethal pH levels. Furthermore, Lmo0036 played a possible role in Listeria virulence.

  3. Citicoline pretreatment protects rats against spinal cord ischemia-reperfusion injury%胞二磷胆碱预处理对大鼠脊髓缺血再灌注损伤的影响

    Institute of Scientific and Technical Information of China (English)

    曾小华; 刘丹彦; 安民

    2011-01-01

    目的 探讨胞二磷胆碱对脊髓缺血再灌注损伤的影响及其作用机制.方法 雄性SD大鼠72只,体质量(230±20)g,按随机数字表法分为3组(n=24):假手术组,缺血再灌注损伤组(IR组)和胞二磷胆碱预先给药组(citi组),各组按灌注后12、24、48、72 h分成4个亚组(n=6).各组均采用改良Zivin法建立脊髓缺血再灌注损伤模型,并于灌注后12、24、48、72 h4个时点采用改良Tarlov法对大鼠脊髓运动和感觉功能进行评分,HE染色观察脊髓L-L5节段的病理学改变,TUNEL法检测脊髓凋亡细胞数,于再灌注后72 h处采用免疫组化方法检测脊髓神经元Bcl-2、Bax、caspase-9表达及Bcl-2与Bax的比值(Bcl-2/Bax).结果 与假手术组相比,IR组和citi组运动和感觉评分均降低,HE染色有明显的病理损伤,TUNEL染色神经细胞凋亡数量增加,免疫组化显示caspase-9、Bcl-2、Bax蛋白表达增加,Bcl-2/Bax降低(P<0.01);与IR组相比,citi组运动和感觉评分高,HE染色形态学损伤较轻,TUNEL染色神经细胞凋亡数量少,免疫组化Bcl-2表达明显增加,Bax、caspase-9表达降低,Bcl-2/Bax升高(P<0.01).结论 胞二磷胆碱可减轻大鼠脊髓缺血再灌注损伤,改善神经功能,其机制可能与其上调Bcl-2蛋白表达,下调Bax、caspase-9蛋白表达,从而减轻神经元凋亡有关.%Objective To determine the effects of citicoline pretreatment on spinal cord ischemia-reperfusion (IR) injury in rats. Methods Seventy-two male SD rats weighing 210 to 250 g were randomly di-vided into 3 groups (n =24) : sham operation group, ischemia-reperfusion injury group (group IR) and citico-line pretreatment group ( group citi). Every group was divided into 4 subgroups according to the time after reperfusion for 12, 24, 48 and 72 h respectively (n = 6). After modified Zivin methods was used to establish model, Tarlov with modification was used for neurological function scores at the above mentioned time points, HE staining was

  4. 40 CFR 403.9 - POTW pretreatment programs and/or authorization to revise pretreatment standards: Submission for...

    Science.gov (United States)

    2010-07-01

    ... with any approved water quality management plan developed in accordance with 40 CFR parts 130, 131, as... Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS GENERAL PRE-TREAT... applied to individual Industrial Users (e.g., by order, permit, ordinance, etc.); and, (iii) Identify...

  5. 40 CFR 429.96 - Pretreatment standards for new sources (PSNS).

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 29 2010-07-01 2010-07-01 false Pretreatment standards for new sources (PSNS). 429.96 Section 429.96 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS TIMBER PRODUCTS PROCESSING POINT SOURCE CATEGORY Wood...

  6. 40 CFR 430.107 - Pretreatment standards for new sources (PSNS).

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 29 2010-07-01 2010-07-01 false Pretreatment standards for new sources (PSNS). 430.107 Section 430.107 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS THE PULP, PAPER, AND PAPERBOARD POINT SOURCE CATEGORY Secondary Fiber...

  7. 40 CFR 471.14 - Pretreatment standards for existing sources (PSES).

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 29 2010-07-01 2010-07-01 false Pretreatment standards for existing sources (PSES). 471.14 Section 471.14 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS NONFERROUS METALS FORMING AND METAL POWDERS POINT SOURCE CATEGORY...

  8. 40 CFR 471.15 - Pretreatment standards for new sources (PSNS).

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 29 2010-07-01 2010-07-01 false Pretreatment standards for new sources (PSNS). 471.15 Section 471.15 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS NONFERROUS METALS FORMING AND METAL POWDERS POINT SOURCE CATEGORY...

  9. 40 CFR 471.35 - Pretreatment standards for new sources (PSNS).

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 29 2010-07-01 2010-07-01 false Pretreatment standards for new sources (PSNS). 471.35 Section 471.35 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS NONFERROUS METALS FORMING AND METAL POWDERS POINT SOURCE CATEGORY...

  10. 40 CFR 471.25 - Pretreatment standards for new sources (PSNS).

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 29 2010-07-01 2010-07-01 false Pretreatment standards for new sources (PSNS). 471.25 Section 471.25 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS NONFERROUS METALS FORMING AND METAL POWDERS POINT SOURCE...

  11. 40 CFR 471.84 - Pretreatment standards for existing sources (PSES). [Reserved

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 29 2010-07-01 2010-07-01 false Pretreatment standards for existing sources (PSES). 471.84 Section 471.84 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS NONFERROUS METALS FORMING AND METAL POWDERS POINT SOURCE CATEGORY...

  12. 40 CFR 471.85 - Pretreatment standards for new sources (PSNS).

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 29 2010-07-01 2010-07-01 false Pretreatment standards for new sources (PSNS). 471.85 Section 471.85 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS NONFERROUS METALS FORMING AND METAL POWDERS POINT SOURCE CATEGORY...

  13. 40 CFR 471.44 - Pretreatment standards for existing sources (PSES).

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 29 2010-07-01 2010-07-01 false Pretreatment standards for existing sources (PSES). 471.44 Section 471.44 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS NONFERROUS METALS FORMING AND METAL POWDERS POINT SOURCE...

  14. 40 CFR 471.24 - Pretreatment standards for existing sources (PSES).

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 29 2010-07-01 2010-07-01 false Pretreatment standards for existing sources (PSES). 471.24 Section 471.24 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS NONFERROUS METALS FORMING AND METAL POWDERS POINT SOURCE...

  15. 40 CFR 471.54 - Pretreatment standards for existing sources (PSES).

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 29 2010-07-01 2010-07-01 false Pretreatment standards for existing sources (PSES). 471.54 Section 471.54 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS NONFERROUS METALS FORMING AND METAL POWDERS POINT SOURCE...

  16. 40 CFR 471.64 - Pretreatment standards for existing sources (PSES).

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 29 2010-07-01 2010-07-01 false Pretreatment standards for existing sources (PSES). 471.64 Section 471.64 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS NONFERROUS METALS FORMING AND METAL POWDERS POINT SOURCE...

  17. 40 CFR 471.55 - Pretreatment standards for new sources (PSNS).

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 29 2010-07-01 2010-07-01 false Pretreatment standards for new sources (PSNS). 471.55 Section 471.55 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS NONFERROUS METALS FORMING AND METAL POWDERS POINT SOURCE...

  18. 40 CFR 471.104 - Pretreatment standards for existing sources (PSES).

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 29 2010-07-01 2010-07-01 false Pretreatment standards for existing sources (PSES). 471.104 Section 471.104 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS NONFERROUS METALS FORMING AND METAL POWDERS POINT...

  19. 40 CFR 471.105 - Pretreatment standards for new sources (PSNS).

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 29 2010-07-01 2010-07-01 false Pretreatment standards for new sources (PSNS). 471.105 Section 471.105 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS NONFERROUS METALS FORMING AND METAL POWDERS POINT SOURCE CATEGORY...

  20. 40 CFR 471.34 - Pretreatment standards for existing sources (PSES).

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 29 2010-07-01 2010-07-01 false Pretreatment standards for existing sources (PSES). 471.34 Section 471.34 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS NONFERROUS METALS FORMING AND METAL POWDERS POINT SOURCE CATEGORY...

  1. 40 CFR 471.45 - Pretreatment standards for new sources (PSNS).

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 29 2010-07-01 2010-07-01 false Pretreatment standards for new sources (PSNS). 471.45 Section 471.45 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS NONFERROUS METALS FORMING AND METAL POWDERS POINT SOURCE...

  2. 40 CFR 471.65 - Pretreatment standards for new sources (PSNS).

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 29 2010-07-01 2010-07-01 false Pretreatment standards for new sources (PSNS). 471.65 Section 471.65 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS NONFERROUS METALS FORMING AND METAL POWDERS POINT SOURCE...

  3. 40 CFR 471.75 - Pretreatment standards for new sources (PSNS).

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 29 2010-07-01 2010-07-01 false Pretreatment standards for new sources (PSNS). 471.75 Section 471.75 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS NONFERROUS METALS FORMING AND METAL POWDERS POINT SOURCE CATEGORY...

  4. 40 CFR 471.74 - Pretreatment standards for existing sources (PSES). [Reserved

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 29 2010-07-01 2010-07-01 false Pretreatment standards for existing sources (PSES). 471.74 Section 471.74 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS NONFERROUS METALS FORMING AND METAL POWDERS POINT SOURCE CATEGORY...

  5. Processes for pretreating lignocellulosic biomass: A review

    Energy Technology Data Exchange (ETDEWEB)

    McMillan, J D

    1992-11-01

    This paper reviews existing and proposed pretreatment processes for biomass. The focus is on the mechanisms by which the various pretreatments act and the influence of biomass structure and composition on the efficacy of particular pretreatment techniques. This analysis is used to identify pretreatment technologies and issues that warrant further research.

  6. Steam pretreatment for coal liquefaction

    Science.gov (United States)

    Ivanenko, Olga

    The objectives of this work are to test the application of steam pretreatment to direct coal liquefaction, to investigate the reaction of model compounds with water, and to explore the use of zeolites in these processes. Previous work demonstrated the effectiveness of steam pretreatment in a subsequent flash pyrolysis. Apparently, subcritical steam ruptures nearly all of the ether cross links, leaving a partially depolymerized structure. It was postulated that very rapid heating of the pretreated coal to liquefaction conditions would be required to preserve the effects of such treatment. Accordingly, a method was adopted in which coal slurry is injected into a hot autoclave containing solvent. Since oxygen is capable of destroying the pretreatment effect, precautions were taken for its rigorous exclusion. Tests were conducted with Illinois No. 6 coal steam treated at 340sp°C, 750 psia for 15 minutes. Both raw and pretreated samples were liquified in deoxygenated tetralin at high severity (400sp°C, 30 min.) and low severity (a: 350sp°C, 30 min., and b: 385sp°C, 15 min.) conditions under 1500 psia hydrogen. Substantial improvement in liquid product quality was obtained and the need for rapid heating and oxygen exclusion demonstrated. Under low severity conditions, the oil yield was more than doubled, going from 12.5 to 29 wt%. Also chemistry of the pretreatment process was studied using aromatic ethers as model compounds. alpha-Benzylnaphthyl ether (alpha-BNE), alpha-naphthylmethyl phenyl (alpha-NMPE), and 9-phenoxyphenanthrene were exposed to steam and inert gas at pretreatment conditions and in some cases to liquid water at 315sp°C. alpha-BNE and alpha-NMPE showed little difference in conversion in inert gas and in steam. Hence, these compounds are poor models for coal in steam pretreatment. Thermally stable 9-phenoxyphenanthrene, however, was completely converted in one hour by liquid water at 315sp°C. At pretreatment conditions mostly rearranged starting

  7. Research on Technology of Pressure Pretreatment with Oxygen for Refractory Gold Ores

    Institute of Scientific and Technical Information of China (English)

    Liu Shengming; Sun Tichang; Chen Jinghe; Wang Dianzuo

    2007-01-01

    An combined technology of pressure pretreatment with oxygen on refractory gold ores is pointed out and discussed on this paper, according to the experiments included the test in 1kg grade batch pressure pretreatment with oxygen of the concentrate from the refractory gold ores of Dongbeizhai in Sichuan province, which is called the most refractory gold ores in China. It is shown that gold recovery reach 91.73% in the combined process which is described as follows: The flotation of the sulphide gold ores is under controlled conditions, producing the concentrate for pressure pretreatment with oxygen in acidic medium and the middling for the pressure pretreatment with oxygen in alkaline medium. The thickening and washing process substitute the pressure filtration process of the pulp after pressure pretreatment. The thick slimes of the two kinds of pressure pretreatment were mixed and then enter the CIL process for simplifying the flowsheet. The possible superabundance of acid of pressure pretreatment with oxygen in acidic medium was neutralized by the tailings of flotation and the cost of neutralization will be lower. The combined technology of pressure pretreatment with oxygen has the same advantages as the normal technology of pressure pretreatment and both is helpful for environment protection.

  8. Study on the Mechanism of mTOR-Mediated Autophagy during Electroacupuncture Pretreatment against Cerebral Ischemic Injury

    Science.gov (United States)

    Wu, Zhou-Quan; Cui, Su-yang; Zhu, Liang

    2016-01-01

    This study is aimed at investigating the association between the electroacupuncture (EA) pretreatment-induced protective effect against early cerebral ischemic injury and autophagy. EA pretreatment can protect cerebral ischemic and reperfusion injuries, but whether the attenuation of early cerebral ischemic injury by EA pretreatment was associated with autophagy is not yet clear. This study used the middle cerebral artery occlusion model to monitor the process of ischemic injury. For rats in the EA pretreatment group, EA pretreatment was conducted at Baihui acupoint before ischemia for 30 min for 5 consecutive days. The results suggested that EA pretreatment significantly increased the expression of autophagy in the cerebral cortical area on the ischemic side of rats. But the EA pretreatment-induced protective effects on the brain could be reversed by the specific inhibitor 3-methyladenine of autophagy. Additionally, the Pearson correlation analysis indicated that the impact of EA pretreatment on p-mTOR (2481) was negatively correlated with its impact on autophagy. In conclusion, the mechanism of EA pretreatment at Baihui acupoint against cerebral ischemic injury is mainly associated with the upregulation of autophagy expression, and its regulation of autophagy may depend on mTOR-mediated signaling pathways. PMID:27547233

  9. 胍丁胺对吗啡戒断大鼠海马神经元型一氧化氮合酶的影响%Effects of agmatine on neuronal nitric oxide synthase in hippocampus of morphine withdrawal rats

    Institute of Scientific and Technical Information of China (English)

    王爱国; 姜雨鸽; 徐龙河

    2006-01-01

    黄色,圆形的细胞核被苏木精染成淡紫色.胍丁胺吗啡组阳性神经元免疫荧光吸光度值较吗啡组显著降低(24.32±8.31,50.82±15.13,P<0.01),与盐水对照组基本相似(24.32±8.31,15.24±1.88,P>0.05).结论:胍丁胺能抑制吗啡的戒断症状,降低吗啡戒断大鼠脑海马CA1区神经元型一氧化氮合酶的活性,海马一氧化氮通路参与胍丁胺抑制吗啡的戒断.%BACKGROUND: Agmatine can enhance the analgesic effect of morphine,and antagonize the tolerant and dependent effect of morphine.OBJECTIVE: To observe the effects of injecting agmatine on the neuronal nitric oxide synthase (nNOS) in hippocampus of morphine withdrawal rats.DESIGN: A randomized controlled experimental study.SETTING: Department of Anesthesiology, the General Hospital of Chinese PLA.MATERIALS: All the experiments were carried out in the Department of anesthesiology, the General Hospital of Chinese PLA between April and July 2004. Eighteen healthy SD rats were randomly divided into saline control group (n=6), morphine group (n=6) and agmatine-treated group (n=6).METHODS: The rats in the saline control group were treated with subcutaneous injection of physiological saline (10 mg/kg), those in the morphine group were treated with 5-day preconditioning, subcutaneous injection of morphine of 10, 20, 30, 40 and 50 mg/kg respectively, twice a day, and those in the agmatine-treated group were treated with subcutaneous injection of agmatine (10 mg/kg) at 30 minutes before morphine was given, but at 6 hours later, before morphine was given for the last time, the rats in the morphine group and agmatine treated group were also given intraperitoneal injection of naloxone (5 mg/kg) to induce morphine withdrawal symptoms.The number of times of the morphine withdrawal symptoms (including physical signs of trembling like a wet dog, chewing, irrigating, drooling, diarrhoea, etc.) were recorded within 1 hour, and the reduction of body mass was calculated

  10. Thermochemical behavior of pretreated biomass

    Energy Technology Data Exchange (ETDEWEB)

    Biswas, Amit Kumar

    2011-07-01

    Mankind has to provide a sustainable alternative to its energy related problems. Bioenergy is considered as one of the potential renewable energy resources and as a result bioenergy market is also expected to grow dramatically in future. However, logistic issues are of serious concern while considering biomass as an alternative to fossil fuel. It can be improved by introducing pretreated wood pellet. The main objective of this thesis is to address thermochemical behaviour of steam exploded pretreated biomass. Additionally, process aspects of torrefaction were also considered in this thesis. Steam explosion (SE) was performed in a laboratory scale reactor using Salix wood chips. Afterwards, fuel and thermochemical aspects of SE residue were investigated. It was found that Steam explosion pretreatment improved both fuel and pellet quality. Pyrolysis of SE residue reveals that alerted biomass composition significantly affects its pyrolysis behaviour. Contribution from depolymerized components (hemicellulose, cellulose and lignin) of biomass was observed explicitly during pyrolysis. When devolatilization experiment was performed on pellet produced from SE residue, effect of those altered components was observed. In summary, pretreated biomass fuel characteristics is significantly different in comparison with untreated biomass. On the other hand, Process efficiency of torrefaction was found to be governed by the choice of appropriate operating conditions and the type of biomass.

  11. Non-enzymatic pretreatment of nerve agent (soman) poisoning: A brief state-of-the-art review

    NARCIS (Netherlands)

    Helden, H.P.M. van; Joosen, M.J.A.; Philippens, I.H.C.H.M.

    2011-01-01

    The rapid onset of toxic signs following nerve agent intoxication and the apprehension that current therapy (atropine, oxime, diazepam) may not prevent brain damage, requires supportive pretreatment. Since the current pretreatment drug pyridostigmine fails in protecting brain-AChE, more effective pr

  12. Carbonic Acid Pretreatment of Biomass

    Energy Technology Data Exchange (ETDEWEB)

    G. Peter van Walsum; Kemantha Jayawardhana; Damon Yourchisin; Robert McWilliams; Vanessa Castleberry

    2003-05-31

    This project sought to address six objectives, outlined below. The objectives were met through the completion of ten tasks. 1) Solidify the theoretical understanding of the binary CO2/H2O system at reaction temperatures and pressures. The thermodynamics of pH prediction have been improved to include a more rigorous treatment of non-ideal gas phases. However it was found that experimental attempts to confirm theoretical pH predictions were still off by a factor of about 1.8 pH units. Arrhenius experiments were carried out and the activation energy for carbonic acid appears to be substantially similar to sulfuric acid. Titration experiments have not yet confirmed or quantified the buffering or acid suppression effects of carbonic acid on biomass. 2) Modify the carbonic acid pretreatment severity function to include the effect of endogenous acid formation and carbonate buffering, if necessary. It was found that the existing severity functions serve adequately to account for endogenous acid production and carbonate effects. 3) Quantify the production of soluble carbohydrates at different reaction conditions and severity. Results show that carbonic acid has little effect on increasing soluble carbohydrate concentrations for pretreated aspen wood, compared to pretreatment with water alone. This appears to be connected to the release of endogenous acids by the substrate. A less acidic substrate such as corn stover would derive benefit from the use of carbonic acid. 4) Quantify the production of microbial inhibitors at selected reaction conditions and severity. It was found that the release of inhibitors was correlated to reaction severity and that carbonic acid did not appear to increase or decrease inhibition compared to pretreatment with water alone. 5) Assess the reactivity to enzymatic hydrolysis of material pretreated at selected reaction conditions and severity. Enzymatic hydrolysis rates increased with severity, but no advantage was detected for the use of carbonic

  13. Lime pretreatment of lignocellulosic biomass

    Science.gov (United States)

    Chang, Shushien

    Lignocellulose is a valuable alternative energy source. The susceptibility of lignocellulosic biomass to enzymatic hydrolysis is constrained due to its structural features, so pretreatment is essential to enhance enzymatic digestibility. Of the chemicals used as pretreatment agents, it has been reported that alkalis improve biomass digestibility significantly. In comparison with other alkalis such as NaOH and ammonia, lime (calcium hydroxide) has many advantages; it is very inexpensive, is safe, and can be recovered by carbonating wash water. The effects of lime pretreatment were explored on switchgrass and poplar wood, representing herbaceous and woody biomass, respectively. The effects of pretreatment conditions (time, temperature, lime loading, water loading, particle size, and oxygen pressure) have been systematically studies. Lime alone enhances the digestibility of switchgrass significantly; under the recommended conditions, the 3-d total sugar (glucose + xylose) yields of lime-treated switchgrass were 7 times that of untreated sample. When treating poplar wood, lime must be combined with oxygen to achieve high digestibility; oxidative lime pretreatment increased the 3-d total sugar yield of poplar wood to 12 times that of untreated sample. In a fundamental study, to determine why lime pretreatment is effective, the effects of three structural features on enzymatic digestibility were studied: lignin content, acetyl content, and crystallinity index (CrI). Poplar wood was treated with peracetic acid, potassium hydroxide, and ball milling to produce model lignocelluloses with a broad spectrum of lignin contents, acetyl contents, and CrI, respectively. Enzymatic hydrolysis was performed on the model lignocelluloses to determine the digestibility. Correlations between lignin/carbohydrate ratio, acetyl/carbohydrate ratio, CrI and digestibility were developed. The 95% prediction intervals show that the correlations predict the 1-h and 3-d total sugar conversions of

  14. Relative effectiveness of pretreatments on performance of Rhizomucor miehei lipase in nonpolar reaction media.

    Science.gov (United States)

    Garcia, Rafael A; Riley, Mark R

    2005-02-01

    Enzymes can be used in nonpolar reaction media to modify water-insoluble substrates. A variety of pretreatments, applied to the enzyme prior to introduction to the nonpolar media, can improve enzyme activity. However, the various pretreatments have not been studied using directly comparable conditions, nor have they been applied simultaneously to test for interactive effects. This work evaluates pretreatment of lipase with various classes of additives. The pretreated lipase is used to catalyze esterification between citronellol and acetic acid in a medium of n-hexane. The effectiveness of a particular pretreatment is presented in terms of relative performance (RP), which is equal to the number of times faster the pretreated lipase catalyzes the reaction relative to untreated lipase. The individual and interactive effects of the pretreatment factors were studied and compared. Buffer salts had a much stronger performance-enhancing effect than nonbuffer salts; pretreatment with 90% (w/w) sodium phosphate yielded lipase with an RP of approx 64. A strong interaction was found between the treatments with sodium phosphate and pH adjustment. These treatments may mitigate the inhibitory effect of acetic acid. Activating effects of phase interfaces and active-site protectants are shown to be complementary to other treatments, demonstrating that they likely act by distinct mechanisms.

  15. 胍丁胺对吗啡镇痛耐受大鼠脊髓和海马锌含量变化的影响%Influence of agmatine on changes of zinc concentrations of spinal cord and hippocampus in morphine antinociceptive tolerance rats

    Institute of Scientific and Technical Information of China (English)

    叶裕良; 肖亮灿; 莫利求; 赵春梅; 郭瑞鲜; 陈培熹; 冯鉴强

    2011-01-01

    Objective To investigate influence of agmatine on changes of zinc levels of spinal cord and hippocampus in morphine antinoceceptive tolerance rats. Methods In the adult Sprague-Dawley rats , chronic morphine tolerance rat model was estahlished. The analgesia effect was assessed by hot-water tail flick test. Animals were randomly divided into 4 groups : salinesaline group, saline-morphine group, Agmatine-saline group and Agmatine-morphine group. The zinc concentrations in spinal cord and hippocampus were examined by atomic absorption spectrometry. Results Agmatine ( 10 mg/kg) coadministrated with morphine significantly antagonized morphine tolerance along with blocking chronic morphine-induced reduction of zinc levels in the spinal cord and hippocampus (P<O.OO1). Conclusion One of the mechanisms underlying the blockage of morphine tolerance by agmatine is to reverse the decrease in zinc levels induced by morphine tolerance.%目的 观察胍丁胺对吗啡耐受大鼠脊髓和海马组织中锌(Zn2+)含量变化的影响.方法 采用SD成年雄性大鼠,建立慢性吗啡耐受大鼠模型,用热水甩尾法测定甩尾潜伏期观察痛反应的变化.动物随机分为4组:生理盐水(NS-NS)组、吗啡(NS-Mor)组、胍丁胺(Ag-NS)组、胍丁胺-吗啡(Ag-Mor)组.用原子吸收光谱法测定各组大鼠的脊髓和海马Zn2+ 含量.结果 胍丁胺(10 mg/kg)与吗啡合用具有显著的抗吗啡耐受作用,并阻断慢性吗啡耐受引起的脊髓和海马Zn2+ 含量的降低(P<0.001).结论 逆转吗啡耐受时脊髓和海马组织中Zn2+含量的减少,可能是胍丁胺抗吗啡耐受的机制之一.

  16. Ca^2+、ABA预处理蝴蝶兰类原球茎的脱水保护系统比较及信号传导关系%Comparison on the Dehydration Protection Systems and Signal Transduction Relationship of CaCl2 and ABA Pretreatment on the Phalaenopsis PLB

    Institute of Scientific and Technical Information of China (English)

    刘福平

    2011-01-01

    CaCl2和ABA溶液及两者联合分别预处理蝴蝶兰类原球茎(PLB)后脱水,对比PLB脱水前后的成活率、脱水保护系统指标变化及Ca^2+与ABA信号传导关系。结果表明,CaCl2和ABA溶液及两者联合预处理均能明显提高PLB脱水后的成活率。CaCl2和ABA溶液对可溶性糖、蔗糖、还原糖、SOD和总抗氧化能力有相同的效应趋势,对可溶性蛋白、热稳定蛋白含量及POD、CAT活性的作用趋势有所差异。ABA溶液提高PLB耐脱水性的能力被胞质Ca^2+螯合剂BAPT~AM和钙调蛋白拮抗剂氯丙嗪所削弱,Ca^2+预处理提高PLB耐脱水能力被ABA合成抑制剂环丙嘧啶醇削弱。在蝴蝶兰PLB的耐脱水性诱导中,Ca^2+和ABA具有基本相同的生理生化基础,在信号传递中两者互相关联,CaCl2取代ABA用于提高PLB耐脱水性是可行的。%In this paper we pretreated Phalaenopsis PLB (protocorm-like body) with CaCl2, ABA and both, respectively, and compared survival rate, dehydration protection system before and after desiccation, as well as the signal transduction relationship between Ca〉 and ABA. The results showed survival rates of dehydrated PLB pretreated with CaCl2, ABA and both all increased significantly. CaCl2 and ABA exhibited similar impact tendencies on the indexes of soluble carbohydrate, sucrose, reducing carbohydrate, SOD activity and antioxidative capability, respectively, but with respect to the indexes of soluble protein, heat-stable protein, POD and CAT, their impact tendencies showed deviation. The ability that ABA increased the dehydration tolerance of PLB was weaken by promethazine (calmodulin antagonist) or BAPTA/AM (cytosolic calcium chelator). Ancymidol (inhibitor of ABA synthesis) decreased the effect of ABA on the PLB's dehydration tolerance. Due to the fact that the effects of CaCl2 and ABA had almost the same basic of physiology and biochemistry, and that ABA and Ca〉 related to

  17. Comparison on the Dehydration Protection Systems and Signal Transduction Relationship of CaCl2 and ABA Pretreatment on the Phalaenopsis PLB%Ca2+、ABA预处理蝴蝶兰类原球茎的脱水保护系统比较及信号传导关系

    Institute of Scientific and Technical Information of China (English)

    刘福平

    2011-01-01

    In this paper we pretreated Phalaenopsis PLB (protocorm-like body) with CaCl2, ABA and both, respectively, and compared survival rate, dehydration protection system before and after desiccation, as well as the signal transduction relationship between Ca2+ and ABA. The results showed survival rates of dehydrated PLB pretreated with CaCl2, ABA and both all increased significantly. CaCl2 and ABA exhibited similar impact tendencies on the indexes of soluble carbohydrate, sucrose, reducing carbohydrate, SOD activity and antioxidative capability, respectively, but with respect to the indexes of soluble protein, heat-stable protein, POD and CAT, their impact tendencies showed deviation. The ability that ABA increased the dehydration tolerance of PLB was weaken by promethazine (calmodulin antagonist) or BAPTA/AM (cytosolic calcium chelator). Ancymidol (inhibitor of ABA synthesis) decreased the effect of ABA on the PLB's dehydration tolerance. Due to the fact that the effects of CaCl2 and ABA had almost the same basic of physiology and biochemistry, and that ABA and Ca2+ related to each other by the signal transduction system during dehydration, it is practical to replace ABA with CaCl2 for pretreatment to induce the dehydration tolerance of Phalaenopsis PLB.%CaCl2和ABA溶液及两者联合分别预处理蝴蝶兰类原球茎(PLB)后脱水,对比PLB脱水前后的成活率、脱水保护系统指标变化及Ca2+与ABA信号传导关系.结果表明,CaCl2和ABA溶液及两者联合预处理均能明显提高PLB脱水后的成活率.CaCl2和ABA溶液对可溶性糖、蔗糖、还原糖、SOD和总抗氧化能力有相同的效应趋势,对可溶性蛋白、热稳定蛋白含量及POD、CAT活性的作用趋势有所差异.ABA溶液提高PLB耐脱水性的能力被胞质Ca2+ 螯合剂BAPTA/AM 和钙调蛋白拮抗剂氯丙嗪所削弱,Ca2+预处理提高PLB耐脱水能力被ABA合成抑制剂环丙嘧啶醇削弱.在蝴蝶兰PLB的耐脱水性诱导中,Ca2+和ABA具有基本

  18. Dilute Acid and Autohydrolysis Pretreatment

    Science.gov (United States)

    Yang, Bin; Wyman, Charles E.

    Exposure of cellulosic biomass to temperatures of about 120-210°C can remove most of the hemicellulose and produce cellulose-rich solids from which high glucose yields are possible with cellulase enzymes. Furthermore, the use of dilute sulfuric acid in this pretreatment operation can increase recovery of hemicellulose sugars substantially to about 85-95% of the maximum possible versus only about 65% if no acid is employed. The use of small-diameter tubes makes it possible to employ high solids concentrations similar to those preferred for commercial operations, with rapid heat-up, good temperature control, and accurate closure of material balances. Mixed reactors can be employed to pretreat larger amounts of biomass than possible in such small-diameter tubes, but solids concentrations are limited to about 15% or less to provide uniform temperatures. Pretreatment of large amounts of biomass at high solids concentrations is best carried out using direct steam injection and rapid pressure release, but closure of material balances in such “steam gun” devices is more difficult. Although flow of water alone or containing dilute acid is not practical commercially, such flow-through configurations provide valuable insight into biomass deconstruction kinetics not possible in the batch tubes, mixed reactors, or steam gun systems.

  19. Melatonin pretreatment protects against focal cerebral ischemia in the rat

    OpenAIRE

    Ho, HTS; Pei, Z; Pang, SF; Cheung, RTF

    2000-01-01

    Melatonin (MT) possesses many properties of an ideal neuroprotectant. In this study, the neuroprotective effects of exogenous MT were tested in a middle cerebral artery occlusion (MCAO) stroke model. Adult male Sprague-Dawley rats (280 to 360 g) were anesthetized with sodium pentobarbital (60 mg/kg, I.P.) to undergo reversible right-sided endovascular MCAO for 3 hours. Arterial blood pressure, heart rate and cerebral blood flow (CBF) were monitored, and rectal temperature was kept between 36....

  20. Adjuvant arthritis pretreatment with type II collagen and Mycobacterium butyricum.

    Science.gov (United States)

    Franch, A; Cassany, S; Castellote, C; Castell, M

    1992-11-01

    A treatment previous to adjuvant arthritis induction has been performed with type II collagen (CII) or Mycobacterium butyricum (Mb), which is the inducer of the pathology. Pretreatment was administered in two different ways: a) subcutaneously or intradermally 14 days before arthritis induction, and b) intravenously 3 days before induction. In order to relate the change in inflammation to the corresponding antigen immune response, serum antibodies and delayed type hypersensitivity (DTH) against CII or Mb were studied. Pretreatment with s.c. CII 14 days before induction produced slight protection against arthritis and significantly delayed its onset; systemic inflammation showed good positive correlation with anti-CII antibodies. The CII administered i.v. 3 days before arthritic challenge did not significantly modify the inflammatory process. The use of i.d. subarthritogenic doses of Mb 14 days before induction protected a high percentage of the animals from the posterior arthritic challenge; this protection was accompanied by high anti-Mb antibody titers and DTH reaction. When Mb was given i.v. 3 days before induction, a partial protection of inflammation was observed; arthritis was milder and its onset was delayed. These changes were accompanied by reduced humoral and cellular response to Mb.

  1. Pretreatment Engineering Platform Phase 1 Final Test Report

    Energy Technology Data Exchange (ETDEWEB)

    Kurath, Dean E.; Hanson, Brady D.; Minette, Michael J.; Baldwin, David L.; Rapko, Brian M.; Mahoney, Lenna A.; Schonewill, Philip P.; Daniel, Richard C.; Eslinger, Paul W.; Huckaby, James L.; Billing, Justin M.; Sundar, Parameshwaran S.; Josephson, Gary B.; Toth, James J.; Yokuda, Satoru T.; Baer, Ellen BK; Barnes, Steven M.; Golovich, Elizabeth C.; Rassat, Scot D.; Brown, Christopher F.; Geeting, John GH; Sevigny, Gary J.; Casella, Amanda J.; Bontha, Jagannadha R.; Aaberg, Rosanne L.; Aker, Pamela M.; Guzman-Leong, Consuelo E.; Kimura, Marcia L.; Sundaram, S. K.; Pires, Richard P.; Wells, Beric E.; Bredt, Ofelia P.

    2009-12-23

    Pacific Northwest National Laboratory (PNNL) was tasked by Bechtel National Inc. (BNI) on the River Protection Project, Hanford Tank Waste Treatment and Immobilization Plant (RPP-WTP) project to conduct testing to demonstrate the performance of the WTP Pretreatment Facility (PTF) leaching and ultrafiltration processes at an engineering-scale. In addition to the demonstration, the testing was to address specific technical issues identified in Issue Response Plan for Implementation of External Flowsheet Review Team (EFRT) Recommendations - M12, Undemonstrated Leaching Processes.( ) Testing was conducted in a 1/4.5-scale mock-up of the PTF ultrafiltration system, the Pretreatment Engineering Platform (PEP). Parallel laboratory testing was conducted in various PNNL laboratories to allow direct comparison of process performance at an engineering-scale and a laboratory-scale. This report presents and discusses the results of those tests.

  2. New Drugs for Pretreatment of Organophosphonate Intoxication

    Science.gov (United States)

    1990-02-20

    COPY A D L£> SRI PROJECT PYU-4681 NEW DRUGS FOR PRETREATMENT OF ORGANOPHOSPHONATE INTOXICATION FINAL REPORT AD-B145 250 Daniel W. Parish, Allen...BB WORK UNIT ACCESSION NO. 099 11. TITLE (indud* Security Oaofficattofl) New Drugs for Pretreatment of Organophosphonate Intoxication...undertaken for the U.S. Army Medical Research and Development Command (MRDC) under Contract DAMD17-88-C-8001, " New Drugs for Pretreatment of

  3. Wash water waste pretreatment system

    Science.gov (United States)

    1977-01-01

    Investigations were completed on wash waters based on each candidate personal cleansing agent. Evaluations of coagulants, antifoam agents, and the effect of promising antifoams on the chemical precipitation were included. Based on these evaluations two candidate soaps as well as their companion antifoam agents were selected for further work. Operating parameters included the effect of soap concentration, ferric chloride concentration, duration of mixing, and pore size of depth filters on the degree of soap removal. The effect of pressure on water flow through filter cartridges and on the rate of decline of water flow was also investigated. The culmination of the program was the recommendation of a pretreatment concept based on chemical precipitation followed by pressure filtration.

  4. Neuroprotective effect of pretreatment with ganoderma lucidum in cerebral ischemia/reperfusion injury in rat hippocampus.

    Science.gov (United States)

    Zhang, Wangxin; Zhang, Quiling; Deng, Wen; Li, Yalu; Xing, Guoqing; Shi, Xinjun; Du, Yifeng

    2014-08-01

    Ganoderma lucidum is a traditional Chinese medicine, which has been shown to have both anti-oxidative and anti-inflammatory effects, and noticeably decreases both the infarct area and neuronal apoptosis of the ischemic cortex. This study aimed to investigate the protective effects and mechanisms of pretreatment with ganoderma lucidum (by intragastric administration) in cerebral ischemia/reperfusion injury in rats. Our results showed that pretreatment with ganoderma lucidum for 3 and 7 days reduced neuronal loss in the hippocampus, diminished the content of malondialdehyde in the hippocampus and serum, decreased the levels of tumor necrosis factor-α and interleukin-8 in the hippocampus, and increased the activity of superoxide dismutase in the hippocampus and serum. These results suggest that pretreatment with ganoderma lucidum was protective against cerebral ischemia/reperfusion injury through its anti-oxidative and anti-inflammatory actions.

  5. New degradation compounds from lignocellulosic biomass pretreatment: routes for formation of potent oligophenolic enzyme inhibitors

    DEFF Research Database (Denmark)

    Rasmussen, H.; Tanner, David Ackland; Sørensen, H. R.

    2017-01-01

    In this study 26 new oligophenol cellulase inhibitors were discovered from wheat straw pretreatment liquors. By consideration of the reaction mechanisms for their formation it is proposed that these oligophenols are formed during hydrothermal biomass pretreatment by pentose self......-condensation reactions involving aldol condensations, 1,4 additions to α,β unsaturated carbonyl compounds, 3-keto acid decarboxylations and oxidations. Furthermore, pentose reactions with phenolic lignin components are suggested. The identification of the central role of xylose in the reaction routes for oligophenolic...... inhibitor formation led to the solution to protect the reactive anomeric center in xylose. It is shown that protection of the anomeric center in in situ generated xylose with ethylene glycol monobutyl ether, during pretreatment of wheat straw, reduces the level of oligophenols by 73%. The results pave...

  6. The protective effects on the renal allografts from brain dead donor rats pretreated with bone marrow mesenchymal stem cells%骨髓间充质干细胞预处理脑死亡供鼠对移植肾的保护作用

    Institute of Scientific and Technical Information of China (English)

    陈洁; 张智; 曾慧兰; 苏泽轩; 余钧雷; 吴永璐; 袁博翔

    2015-01-01

    Objective To investigate the protective effects on the renal allografts from brain dead (BD) donor rats pretreated with bone marrow mesenchymal stem cells (MSCs).Method Three groups [normal transplant group (G1).BD transplant group (G2),and MSCs pretreated + BD transplant group (G3)] were set up.Male F344 rats served as donors and male Lewis rats as recipients.In G1,kidneys from F344 donor rats were implanted into Lewis recipients.In G2,kidneys from F344 BD donor rats were engrafted into Lewis recipients.In G3,after BD was established in F344 rats,MSCs were given intravenously to the rats.The kidneys harvested 6 h later were transplanted to Lewis recipients.Cyclosporine was intromuscularly given daily to the recipient rats for 10 days.Right kidneys were resected from recipients on day 10.Creatinine level was examined on day 14,21,28,and 35.Renal allografts harvested on day 35 were pathologically detected.The irnmunochemistry expression of interleukin (IL)-1β and tumor necrotic factor (TNF)-α in renal allograft tissue was tested.Result Serum creatinine levels in G2 were remarkably higher than those in G1 and G3 (P<0.01) on day 14,21,28,and 35 postoperatively.The creatinine levels on the above mentioned time points had no statistically significant difference between G3 and G1 except on day 21.Postoperative pathological changes in G2 of both pronounced infiltration of mononuclear cells and tubular epithelia[inflammation were notably increased in renal allografts as compared with those in G1 and G3.There was no obvious difference between G1 and G3 in infiltrated mononuclear cells and tubular epithelial inflammation.Positive expression levels of both IL-1β and TNF-α in glomerular,tubular and interstitial epithelial cells were statistically enhanced in G2 as compared with those in G1 and G3 (H =7.210,P =0.027),while there was no statistically significant difference in the expression of both IL-1[β and TNF-α between G1 and G3.Conclusion Brain dead donor rats

  7. Pretreatment of the macroalgae Chaetomorpha linum for the production of bioethanol - Comparison of five pretreatment technologies

    DEFF Research Database (Denmark)

    Schultz-Jensen, Nadja; Thygesen, Anders; Thomsen, Sune Tjalfe

    2013-01-01

    A qualified estimate for pretreatment of the macroalgae Chaetomorpha linum for ethanol production was given, based on the experience of pretreatment of land-based biomass. C. linum was subjected to hydrothermal pretreatment (HTT), wet oxidation (WO), steam explosion (STEX), plasma......-assisted pretreatment (PAP) and ball milling (BM), to determine effects of the pretreatment methods on the conversion of C. linum into ethanol by simultaneous saccharification and fermentation (SSF). WO and BM showed the highest ethanol yield of 44. g ethanol/100. g glucan, which was close to the theoretical ethanol...... yield of 57. g ethanol/100. g glucan. A 64% higher ethanol yield, based on raw material, was reached after pretreatment with WO and BM compared with unpretreated C. linum, however 50% of the biomass was lost during WO. Results indicated that the right combination of pretreatment and marine macroalgae...

  8. Pretreatment of Lignocellulosic Wastes to Improve Ethanol and Biogas Production: A Review

    Directory of Open Access Journals (Sweden)

    Keikhosro Karimi

    2008-09-01

    Full Text Available Lignocelluloses are often a major or sometimes the sole components of different waste streams from various industries, forestry, agriculture and municipalities. Hydrolysis of these materials is the first step for either digestion to biogas (methane or fermentation to ethanol. However, enzymatic hydrolysis of lignocelluloses with no pretreatment is usually not so effective because of high stability of the materials to enzymatic or bacterial attacks. The present work is dedicated to reviewing the methods that have been studied for pretreatment of lignocellulosic wastes for conversion to ethanol or biogas. Effective parameters in pretreatment of lignocelluloses, such as crystallinity, accessible surface area, and protection by lignin and hemicellulose are described first. Then, several pretreatment methods are discussed and their effects on improvement in ethanol and/or biogas production are described. They include milling, irradiation, microwave, steam explosion, ammonia fiber explosion (AFEX, supercritical CO2 and its explosion, alkaline hydrolysis, liquid hot-water pretreatment, organosolv processes, wet oxidation, ozonolysis, dilute- and concentrated-acid hydrolyses, and biological pretreatments.

  9. Exenatide Pretreatment Improved Graft Function in Nonhuman Primate Islet Recipients Compared to Treatment after Transplant Only

    Directory of Open Access Journals (Sweden)

    Jill L. Buss

    2012-01-01

    Full Text Available The GLP-1 receptor agonist, exenatide, has previously been shown to improve insulin secretion, protect beta cells from apoptosis, and promote beta cell regeneration. We propose that pretreatment with exenatide will promote islet graft survival and improve graft function. Pancreatectomized cynomolgus monkeys underwent islet allotransplantation and were treated with exenatide beginning on day 0 or day −2. A third group of animals was treated with an immunosuppressive regimen while a fourth group remained untreated. Fasting blood glucose (FBG was used to evaluate graft function along with intravenous glucose tolerance tests (IVGTTs performed at study endpoint (day 10 for untreated and posttransplant exenatide or day 90 for pretreatment exenatide and immunosuppression. The average FBG for pre-treated animals day 5 following transplant was 52.7±14.8 mg/dl, compared to 154.3±105.5 mg/dl for animals treated only following transplant, 59.4 mg/dl ±12.1 for animals treated with immunosuppression, and 265.5±172.3 mg/dl for untreated animals. IVGTTs performed at study endpoint showed normal glucose and insulin curves in the pre-treated exenatide and immunosuppression groups only, with beta cell function actually improving after transplant in the pre-treated group. We conclude, therefore, that exenatide pre-treatment can successfully maintain islet graft survival in nonhuman primates.

  10. Neuroprotective efficacy of pharmacological pretreatment and antidotal treatment in tabun-poisoned rats.

    Science.gov (United States)

    Krejcová, G; Kassa, J

    2003-03-14

    To study the influence of pharmacological pretreatment (PANPAL) and antidotal treatment (obidoxime plus atropine) on tabun-induced neurotoxicity, male albino rats were poisoned with a lethal dose of tabun (280 microg/kg i.m.; 100% of LD(50) value) and observed at 24 h and 7 days following tabun challenge. The neurotoxicity of tabun was evaluated using a functional observational battery (FOB) and an automatic measurement of motor activity. Pharmacological pretreatment as well as antidotal treatment were able to eliminate most of tabun-induced neurotoxic effects observed at 24 h following tabun poisoning. However, there was not significant difference between the efficacy of PANPAL and antidotal treatment to eliminate tabun-induced neurotoxicity in rats. The combination of PANPAL pretreatment and antidotal treatment seems to be slightly more effective in the elimination of tabun-induced neurotoxicity in rats at 24 h following tabun challenge in comparison with the administration of PANPAL pretreatment or antidotal treatment alone. At 7 days following tabun poisoning, very few neurotoxic signs in tabun-poisoned rats were observed regardless of administration of pharmacological pretreatment or antidotal treatment. Thus, our findings confirm that the combination of pharmacological pretreatment and antidotal treatment is not only able to protect the experimental animals from the lethal effects of tabun but also to eliminate most of tabun-induced signs of neurotoxicity in tabun-poisoned rats.

  11. Steroids pretreatment in assisted reproduction cycles.

    Science.gov (United States)

    Sobotka, V; Streda, R; Mardesic, T; Tosner, J; Heracek, J

    2014-01-01

    The objective is to present an overview of trials and appreciate the relevant data on the effect of steroids pretreatment (oral contraceptives, 17β-estradiol and estradiol valerate) in assisted reproduction cycles. The subject of the study is to evaluate the clinical characteristics during steroids pretreatment cycles focused on the prevention of ovarian cysts, the positive contraceptive effect on the onset of regular period during long gonadotropin releasing hormone agonist protocol. In gonadotropin releasing hormone antagonist protocol the review is interested in supporting ovarian stimulation in low responders, the idea of cycle scheduling and improving treatment outcomes. The method is a review from MEDLINE/Pubmed database between 1994 and July 2012. We identified 15 randomised controlled trials (n=3069 patients). One trail (n=83 patients) assessed GnRH agonist protocol with or without steroids pretreatment, 8 trials (n=1884 patients) assessed GnRH antagonist protocols with or without steroids pretreatment and 6 trials (n=1102 patients) assessed GnRH antagonist protocols versus agonist ones with steroid pretreatment. Data demonstrates that oral contraceptives offer the effective prevention of functional ovarian cysts, the predictable onset of period during desensitisation. Existing data suggest that pretreatment with oral contraceptive pills or estradiol valerate give no advantage concerning number of oocytes or pregnancy rate. Pretreatment with oral contraceptive pills aiming to avoid weekend oocytes retrievals has to be more elucidated. In low responders oral contraceptive pill pretreatment may be beneficial in improving ovarian responses by reducing the amount of gonadotropins and the number of days required for ovarian stimulation. Current research indicates that also 17β-estradiol may be encouraging pretreatment in low responders and in cycle scheduling. This article is part of a Special Issue entitled 'Pregnancy and Steroids'.

  12. Integrated analysis of hydrothermal flow through pretreatment

    Directory of Open Access Journals (Sweden)

    Archambault-Leger Veronique

    2012-07-01

    Full Text Available Abstract Background The impact of hydrothermal flowthrough (FT pretreatment severity on pretreatment and solubilization performance metrics was evaluated for three milled feedstocks (corn stover, bagasse, and poplar and two conversion systems (simultaneous saccharification and fermentation using yeast and fungal cellulase, and fermentation by Clostridium thermocellum. Results Compared to batch pretreatment, FT pretreatment consistently resulted in higher XMG recovery, higher removal of non-carbohydrate carbon and higher glucan solubilization by simultaneous saccharification and fermentation (SSF. XMG recovery was above 90% for FT pretreatment below 4.1 severity but decreased at higher severities, particularly for bagasse. Removal of non-carbohydrate carbon during FT pretreatment increased from 65% at low severity to 80% at high severity for corn stover, and from 40% to 70% for bagasse and poplar. Solids obtained by FT pretreatment were amenable to high conversion for all of the feedstocks and conversion systems examined. The optimal time and temperature for FT pretreatment on poplar were found to be 16 min and 210°C. At these conditions, SSF glucan conversion was about 85%, 94% of the XMG was removed, and 62% of the non carbohydrate mass was solubilized. Solubilization of FT-pretreated poplar was compared for C. thermocellum fermentation (10% inoculum, and for yeast-fungal cellulase SSF (5% inoculum, cellulase loading of 5 and 10 FPU/g glucan supplemented with β-glucosidase at 15 and 30 U/g glucan. Under the conditions tested, which featured low solids concentration, C. thermocellum fermentation achieved faster rates and more complete conversion of FT-pretreated poplar than did SSF. Compared to SSF, solubilization by C. thermocellum was 30% higher after 4 days, and was over twice as fast on ball-milled FT-pretreated poplar. Conclusions XMG removal trends were similar between feedstocks whereas glucan conversion trends were significantly

  13. Temperature Modelling of the Biomass Pretreatment Process

    DEFF Research Database (Denmark)

    2012-01-01

    In a second generation biorefinery, the biomass pretreatment stage has an important contribution to the efficiency of the downstream processing units involved in biofuel production. Most of the pretreatment process occurs in a large pressurized thermal reactor that presents an irregular temperature...... distribution. Therefore, an accurate temperature model is critical for observing the biomass pretreatment. More than that, the biomass is also pushed with a constant horizontal speed along the reactor in order to ensure a continuous throughput. The goal of this paper is to derive a temperature model...

  14. Understanding Ionic Liquid Pretreatment of Lignocellulosic Biomasses

    Science.gov (United States)

    Pretreatment of biomass is essential for breaking apart highly ordered and crystalline plant cell walls and loosening the lignin and hemicellulose conjugation to cellulose microfibrills, thereby facilitating enzyme accessibility and adsorption and reducing costs of downstream saccharification proces...

  15. Extrusion Pretreatment of Lignocellulosic Biomass: A Review

    Directory of Open Access Journals (Sweden)

    Jun Zheng

    2014-10-01

    Full Text Available Bioconversion of lignocellulosic biomass to bioethanol has shown environmental, economic and energetic advantages in comparison to bioethanol produced from sugar or starch. However, the pretreatment process for increasing the enzymatic accessibility and improving the digestibility of cellulose is hindered by many physical-chemical, structural and compositional factors, which make these materials difficult to be used as feedstocks for ethanol production. A wide range of pretreatment methods has been developed to alter or remove structural and compositional impediments to (enzymatic hydrolysis over the last few decades; however, only a few of them can be used at commercial scale due to economic feasibility. This paper will give an overview of extrusion pretreatment for bioethanol production with a special focus on twin-screw extruders. An economic assessment of this pretreatment is also discussed to determine its feasibility for future industrial cellulosic ethanol plant designs.

  16. Pretreatment techniques for biofuels and biorefineries

    Energy Technology Data Exchange (ETDEWEB)

    Fang, Zhen (ed.) [Chinese Academy of Sciences, Kunming, YN (China). Xishuangbanna Tropical Botonical Garden

    2013-02-01

    The first book focused on pretreatment techniques for biofuels contributed by the world's leading experts. Extensively covers the different types of biomass, various pretreatment approaches and methods that show the subsequent production of biofuels and chemicals. In addition to traditional pretreatment methods, novel techniques are also introduced and discussed. An accessible reference work for students, researchers, academicians and industrialists in biorefineries. This book includes 19 chapters contributed by the world's leading experts on pretreatment methods for biomass. It extensively covers the different types of biomass (e.g. molasses, sugar beet pulp, cheese whey, sugarcane residues, palm waste, vegetable oil, straws, stalks and wood), various pretreatment approaches (e.g. physical, thermal, chemical, physicochemical and biological) and methods that show the subsequent production of biofuels and chemicals such as sugars, ethanol, extracellular polysaccharides, biodiesel, gas and oil. In addition to traditional methods such as steam, hot-water, hydrothermal, diluted-acid, organosolv, ozonolysis, sulfite, milling, fungal and bacterial, microwave, ultrasonic, plasma, torrefaction, pelletization, gasification (including biogas) and liquefaction pretreatments, it also introduces and discusses novel techniques such as nano and solid catalysts, organic electrolyte solutions and ionic liquids. This book offers a review of state-of-the-art research and provides guidance for the future paths of developing pretreatment techniques of biomass for biofuels, especially in the fields of biotechnology, microbiology, chemistry, materials science and engineering. It intends to provide a systematic introduction of pretreatment techniques. It is an accessible reference work for students, researchers, academicians and industrialists in biorefineries.

  17. Pretreatment with scutellaria baicalensis stem-leaf total flavonoid prevents cerebral ischemia-reperfusion injury

    Institute of Scientific and Technical Information of China (English)

    Shumin Zhao; Wei Kong; Shufeng Zhang; Meng Chen; Xiaoying Zheng; Xiangyu Kong

    2013-01-01

    Pretreatment with scutel aria baicalensis stem-leaf total flavonoid has protective effects against ischemia and attenuates myocardial ischemia-reperfusion injury. In this study, rats were given scu-tel aria baicalensis stem-leaf total flavonoid intragastrical y at 50, 100, and 200 mg/kg per day for 7 days before focal cerebral ischemia-reperfusion injury models were established using the suture method. We then determined the protective effects of scutel aria baicalensis stem-leaf total flavo-noid pretreatment on focal cerebral ischemia-reperfusion injury. Results showed that neurological deficit scores increased, infarct volumes enlarged, apoptosis increased and Bcl-2 and Bax protein expression were upregulated at 24 hours after reperfusion. Pretreatment with scutel aria baicalensis stem-leaf total flavonoid at any dose lowered the neurological deficit scores, reduced the infarct volume, prevented apoptosis in hippocampal cells, attenuated neuronal and blood-brain barrier damage and upregulated Bcl-2 protein expression but inhibited Bax protein expression. Doses of 100 and 200 mg/kg were the most efficacious. Our findings indicate that pretreatment with scutel a-ria baicalensis stem-leaf total flavonoid at 100 and 200 mg/kg can improve the neurological func-tions and have preventive and protective roles after focal cerebral ischemia-reperfusion injury.

  18. Comparative AMS radiocarbon dating of pretreated versus non-pretreated tropical wood samples

    Energy Technology Data Exchange (ETDEWEB)

    Patrut, Adrian [Department of Chemistry, Babes-Bolyai University, 400028 Cluj-Napoca (Romania); Reden, Karl F. von, E-mail: kvonreden@whoi.ed [NOSAMS Facility, Department of Geology and Geophysics, Woods Hole Oceanographic Institution, Woods Hole, MA 02543 (United States); Lowy, Daniel A. [Nova Research Inc., Alexandria, VA 22308 (United States); Mayne, Diana H. [Baobab Trust, P.O. Box 1566, Parklands 2121, Johannesburg (South Africa); Elder, Kathryn E.; Roberts, Mark L.; McNichol, Ann P. [NOSAMS Facility, Department of Geology and Geophysics, Woods Hole Oceanographic Institution, Woods Hole, MA 02543 (United States)

    2010-04-15

    Several wood samples collected from Dorslandboom, a large iconic African baobab (Adansonia digitata L.) from Namibia, were investigated by AMS radiocarbon dating subsequent to pretreatment and, alternatively, without pretreatment. The comparative statistical evaluation of results showed that there were no significant differences between fraction modern values and radiocarbon dates of the samples analyzed after pretreatment and without pretreatment, respectively. The radiocarbon date of the oldest sample was 993 +- 20 BP. Dating results also revealed that Dorslandboom is a multi-generation tree, with several stems showing different ages.

  19. Comparative AMS radiocarbon dating of pretreated versus non-pretreated tropical wood samples

    Science.gov (United States)

    Patrut, Adrian; von Reden, Karl F.; Lowy, Daniel A.; Mayne, Diana H.; Elder, Kathryn E.; Roberts, Mark L.; McNichol, Ann P.

    2010-04-01

    Several wood samples collected from Dorslandboom, a large iconic African baobab ( Adansonia digitata L.) from Namibia, were investigated by AMS radiocarbon dating subsequent to pretreatment and, alternatively, without pretreatment. The comparative statistical evaluation of results showed that there were no significant differences between fraction modern values and radiocarbon dates of the samples analyzed after pretreatment and without pretreatment, respectively. The radiocarbon date of the oldest sample was 993 ± 20 BP. Dating results also revealed that Dorslandboom is a multi-generation tree, with several stems showing different ages.

  20. Radiation Protection

    Science.gov (United States)

    ... EPA United States Environmental Protection Agency Search Search Radiation Protection Share Facebook Twitter Google+ Pinterest Contact Us Radiation Protection Document Library View and download EPA radiation ...

  1. Bench-Scale Filtration Testing in Support of the Pretreatment Engineering Platform (PEP)

    Energy Technology Data Exchange (ETDEWEB)

    Billing, Justin M.; Daniel, Richard C.; Kurath, Dean E.; Peterson, Reid A.

    2009-09-28

    Pacific Northwest National Laboratory (PNNL) has been tasked by Bechtel National Inc. (BNI) on the River Protection Project-Hanford Tank Waste Treatment and Immobilization Plant (RPP-WTP) project to perform research and development activities to resolve technical issues identified for the Pretreatment Facility (PTF). The Pretreatment Engineering Platform (PEP) was designed, constructed and operated as part of a plan to respond to issue M12, “Undemonstrated Leaching Processes.” The PEP is a 1/4.5-scale test platform designed to simulate the WTP pretreatment caustic leaching, oxidative leaching, ultrafiltration solids concentration, and slurry washing processes. The PEP testing program specifies that bench-scale testing is to be performed in support of specific operations, including filtration, caustic leaching, and oxidative leaching.

  2. Pretreatment with pyridinium oximes improves antidotal therapy against tabun poisoning.

    Science.gov (United States)

    Lucić Vrdoljak, Ana; Calić, Maja; Radić, Bozica; Berend, Suzana; Jun, Daniel; Kuca, Kamil; Kovarik, Zrinka

    2006-11-10

    Oximes K033 [1,4-bis(2-hydroxyiminomethylpyridinium) butane dibromide] and K048 [1-(4-hydroxyiminomethylpyridinium)-4-(4-carbamoylpyridinium) butane dibromide] were tested as pretreatment drugs in tabun-poisoned mice followed by treatment with atropine plus K033, K048, K027 [1-(4-hydroxyiminomethylpyridinium)-3-(4-carbamoylpyridinium) propane dibromide], TMB-4 [1,3-bis(4-hydroxyiminomethylpyridinium) propane dibromide] and HI-6 [(1-(2-hydroxyiminomethylpyridinium)-3-(4-carbamoylpyridinium)-2-oxapropane dichloride)]. Oxime doses of 25% or 5% of its LD(50) were used for pretreatment 15 min before tabun-poisoning and for treatment 1 min after tabun administration to mice. The best therapeutic effect was obtained when oxime K048 (25% of its LD(50)) was used in both pretreatment and treatment with atropine. This regiment insured survival of all tested animals after the application of 10 LD(50) of tabun. In addition, since butyrylcholinesterase (BChE; EC 3.1.1.8) is considered an endogenous bioscavenger of anticholinesterase compounds and its interactions with oximes could be masked by AChE interactions, we evaluated kinetic parameters for interactions of tested oximes with native and tabun-inhibited human plasma BChE and compared them with results obtained previously for human erythrocyte acetylcholinesterase (AChE; EC 3.1.1.7). Progressive inhibition of BChE by tabun was slightly faster than that of AChE. The reactivation of tabun-inhibited BChE by oximes was very slow, and BChE binding affinity for oximes was lower than AChE's. Therefore, BChE could scavenge tabun prior to AChE inhibition, but fast oxime-assisted reactivation of tabun-inhibited AChE or protection of AChE by oxime against inhibition with tabun would not be obstructed by interaction between BChE and oximes.

  3. Microwave pretreatment of switchgrass for bioethanol production

    Science.gov (United States)

    Keshwani, Deepak Radhakrishin

    Lignocellulosic materials are promising alternative feedstocks for bioethanol production. These materials include agricultural residues, cellulosic waste such as newsprint and office paper, logging residues, and herbaceous and woody crops. However, the recalcitrant nature of lignocellulosic biomass necessitates a pretreatment step to improve the yield of fermentable sugars. The overall goal of this dissertation is to expand the current state of knowledge on microwave-based pretreatment of lignocellulosic biomass. Existing research on bioenergy and value-added applications of switchgrass is reviewed in Chapter 2. Switchgrass is an herbaceous energy crop native to North America and has high biomass productivity, potentially low requirements for agricultural inputs and positive environmental impacts. Based on results from test plots, yields in excess of 20 Mg/ha have been reported. Environmental benefits associated with switchgrass include the potential for carbon sequestration, nutrient recovery from run-off, soil remediation and provision of habitats for grassland birds. Published research on pretreatment of switchgrass reported glucose yields ranging from 70-90% and xylose yields ranging from 70-100% after hydrolysis and ethanol yields ranging from 72-92% after fermentation. Other potential value-added uses of switchgrass include gasification, bio-oil production, newsprint production and fiber reinforcement in thermoplastic composites. Research on microwave-based pretreatment of switchgrass and coastal bermudagrass is presented in Chapter 3. Pretreatments were carried out by immersing the biomass in dilute chemical reagents and exposing the slurry to microwave radiation at 250 watts for residence times ranging from 5 to 20 minutes. Preliminary experiments identified alkalis as suitable chemical reagents for microwave-based pretreatment. An evaluation of different alkalis identified sodium hydroxide as the most effective alkali reagent. Under optimum pretreatment

  4. Assessing Pretreatment Reactor Scaling Through Empirical Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Lischeske, James J.; Crawford, Nathan C.; Kuhn, Erik; Nagle, Nicholas J.; Schell, Daniel J.; Tucker, Melvin P.; McMillan, James D.; Wolfrum, Edward J.

    2016-12-01

    Pretreatment is a critical step in the biochemical conversion of lignocellulosic biomass to fuels and chemicals. Due to the complexity of the physicochemical transformations involved, predictively scaling up technology from bench- to pilot-scale is difficult. This study examines how pretreatment effectiveness under nominally similar reaction conditions is influenced by pretreatment reactor design and scale using four different pretreatment reaction systems ranging from a 3 g batch reactor to a 10 dry-ton/d continuous reactor. The reactor systems examined were an Automated Solvent Extractor (ASE), Steam Explosion Reactor (SER), ZipperClave(R) reactor (ZCR), and Large Continuous Horizontal-Screw Reactor (LHR). To our knowledge, this is the first such study performed on pretreatment reactors across a range of reaction conditions (time and temperature) and at different reactor scales. The comparative pretreatment performance results obtained for each reactor system were used to develop response surface models for total xylose yield after pretreatment and total sugar yield after pretreatment followed by enzymatic hydrolysis. Near- and very-near-optimal regions were defined as the set of conditions that the model identified as producing yields within one and two standard deviations of the optimum yield. Optimal conditions identified in the smallest-scale system (the ASE) were within the near-optimal region of the largest scale reactor system evaluated. A reaction severity factor modeling approach was shown to inadequately describe the optimal conditions in the ASE, incorrectly identifying a large set of sub-optimal conditions (as defined by the RSM) as optimal. The maximum total sugar yields for the ASE and LHR were 95%, while 89% was the optimum observed in the ZipperClave. The optimum condition identified using the automated and less costly to operate ASE system was within the very-near-optimal space for the total xylose yield of both the ZCR and the LHR, and was

  5. Lignocellulosic biomass-Thermal pretreatment with steam: Pretreatment techniques for biofuels and biorefineries

    DEFF Research Database (Denmark)

    Toor, Saqib; Rosendahl, Lasse; Hoffmann, Jessica

    2013-01-01

    With the ever rising demand for more energy and the limited availability of depleted world resources, many are beginning to look for alternatives to fossil fuels. Liquid biofuel, in particular, is of key interest to decrease our dependency on fuels produced from imported petroleum. Biomass pre......-treatment remains one of the most pressing challenges in terms of cost-effective production of biofuels. The digestibility of lingo-cellulosic biomass is limited by different factors such as the lignin content, the crystallinity of cellulose, and the available cellulose accessibility to hydrolytic enzymes. A number...... of different pretreatment methods are known to enhance the digestibility of lingo-cellulosic biomass by affecting these limiting factors. Some of them are: milling, thermal pretreatment with steam or hot water, acid pre-treatment and alkaline pre-treatment. This chapter will focus on one of the more promising...

  6. Excimer laser pretreatment and metallization of polymers

    Science.gov (United States)

    Horn, H.; Beil, S.; Wesner, D. A.; Weichenhain, R.; Kreutz, E. W.

    1999-05-01

    Metal/polymer adhesion is a crucial factor of many applications in microelectronic or microsystem technologies. It depends on chemical and structural properties of the interface, often involving just a few atomic layers. Adhesion can be influenced by various pretreatments prior to metal deposition, e.g. thermal treatment, chemical etching or exposure to reactive plasmas. Irradiation with pulsed UV-laser radiation and or UV-excimer lamps can also affect adhesion and offers several technical advantages, among them area selective pretreatment and subsequent metallization. The pretreatment of polymer surfaces by UV-radiation is investigated as an alternative technique to common wet chemical, plasma or other pretreatment methods. Chemical and morphological changes in the polymer surface are investigated with poly(butylene terephthalate) (PBT) as a model substance, containing UV-absorbing (aromatic) chromophoric groups. Chemical changes in the surface are investigated via X-ray photoelectron spectroscopy (XPS) and Fourier-transform infrared spectroscopy (FTIR). Analysis of the morphological changes in the polymer surface is done via optical microscopy and scanning electron microscopy (SEM). The metallization of polymers pretreated by excimer laser radiation is performed via electroless plating of nickel followed by electrolytically deposited copper. The influence of excimer laser irradiation of the polymer on the adhesion of the metal overlayers is measured by tape and peel tests.

  7. Oxidative lime pretreatment of Alamo switchgrass.

    Science.gov (United States)

    Falls, Matthew; Holtzapple, Mark T

    2011-09-01

    Previous studies have shown that oxidative lime pretreatment is an effective delignification method that improves the enzymatic digestibility of many biomass feedstocks. The purpose of this work is to determine the recommended oxidative lime pretreatment conditions (reaction temperature, time, pressure, and lime loading) for Alamo switchgrass (Panicum virgatum). Enzymatic hydrolysis of glucan and xylan was used to determine the performance of the 52 studied pretreatment conditions. The recommended condition (110°C, 6.89 bar O(2), 240 min, 0.248 g Ca(OH)(2)/g biomass) achieved glucan and xylan overall yields (grams of sugar hydrolyzed/100 g sugar in raw biomass, 15 filter paper units (FPU)/g raw glucan) of 85.9 and 52.2, respectively. In addition, some glucan oligomers (2.6 g glucan recovered/100 g glucan in raw biomass) and significant levels of xylan oligomers (26.0 g xylan recovered/100 g xylan in raw biomass) were recovered from the pretreatment liquor. Combining a decrystallization technique (ball milling) with oxidative lime pretreatment further improved the overall glucan yield to 90.0 (7 FPU/g raw glucan).

  8. Oxidative lime pretreatment of Dacotah switchgrass.

    Science.gov (United States)

    Falls, Matthew; Sierra-Ramirez, Rocio; Holtzapple, Mark T

    2011-09-01

    Oxidative lime pretreatment increases the enzymatic digestibility of lignocellulosic biomass primarily by removing lignin. In this study, recommended pretreatment conditions (reaction temperature, oxygen pressure, lime loading, and time) were determined for Dacotah switchgrass. Glucan and xylan overall hydrolysis yields (72 h, 15 FPU/g raw glucan) were measured for 105 different reaction conditions involving three different reactor configurations (very short term, short term, and long term). The short-term reactor was the most productive. At the recommended pretreatment condition (120 °C, 6.89 bar O(2), 240 min), it achieved an overall glucan hydrolysis yield of 85.2 g glucan hydrolyzed/100 g raw glucan and an overall xylan yield of 50.1 g xylan hydrolyzed/100 g raw xylan. At this condition, glucan oligomers (1.80 g glucan recovered/100 g glucan in raw biomass) and xylan oligomers (25.20 g xylan recovered/100 g xylan in raw biomass) were recovered from the pretreatment liquor, which compensate for low pretreatment yields.

  9. Effects of various pretreatments on biohydrogen production from sewage sludge

    Institute of Scientific and Technical Information of China (English)

    XIAO BenYi; LIU JunXin

    2009-01-01

    The sewage sludge of wastewater treatment plant is a kind of biomass which contains many organics,mainly carbohydrates and proteins. Four pretreatments, acid pretreatment, alkaline pretreatment,thermal pretreatment and ultrasonic pretreatment, were used to enhance biohydrogen production from sewage sludge. The experimental results showed that the four pretreatments could all increase the soluble chemical oxygen demand (SCOD) of sludge and decrease the dry solid (DS) and volatile solid(VS) because the pretreatments could disrupt the floc structure and even the microbial cells of sludge.The results of batch anaerobic fermentation experiments demonstrated that all of the four pretreat-ments could select hydrogen-producing microorganisms from the microflora of sludge and enhance the hydrogen production. The hydrogen yield of the alkaline pretreated sludge at initial pH of 11.5 was the maximal (11.68 mL H2/g VS) and that of the thermal pretreated sludge was the next (8.62 mL H2/g VS).The result showed that the hydrogen yield of pretreated sludge was correlative with its SCOD. The hydrogen yields of acid pretreated sludge and alkaline pretreated sludge were also influenced by their initial pH. No methane could be detected in the anaerobic fermentation of alkaline pretreated sludge and thermal pretreated sludge, which suggested that these pretreatments could fully inhibit the activity of methanogens. The volatile fatty acids (VFA) production in anaerobic fermentation of alkaline pretreated sludge was the maximum and the next is that of thermal pretreated sludge.

  10. Pretreatment imaging of peripheral vascular malformations

    Directory of Open Access Journals (Sweden)

    Johnson JB

    2014-10-01

    Full Text Available Joshua B Johnson, Petrice M Cogswell, Michael A McKusick, Larry A Binkovitz, Stephen J Riederer, Phillip M Young Department of Radiology, Mayo Clinic, Rochester, MN, USA Abstract: Peripheral vascular malformations (VMs are complex and diverse vascular lesions which require individualized pretreatment planning. Pretreatment imaging using various modalities, especially magnetic resonance imaging and time-resolved magnetic resonance angiography, is a valuable tool for classifying peripheral VMs to allow proper diagnosis, demonstrate complete extent, identify the nidus, and distinguish between low-flow and high-flow dynamics that determines the treatment approach. We discuss pretreatment imaging findings in four patients with peripheral VMs and how diagnostic imaging helped guide management. Keywords: time-resolved MRA, cartesian acquisition with projection-like reconstruction, endovascular treatment, magnetic resonance angiography

  11. Pretreatment of Corn Stalk by Steam Explosion

    Institute of Scientific and Technical Information of China (English)

    邵自强; 田永生; 谭惠民

    2003-01-01

    A steam explosion pretreatment, which is one of the best ways of pretreating plant stalk, is applied at various severities to corn stalk. It could effectively modify the super-molecular structure of corn stalk and defibrating corn stalk into individual components. The relationship between yield of reducing sugar and the operating conditions, including temperature, pressure of steam explosion pretreatment and acidity, is also established. Experimental results prove that the steam explosion substantially increases the yield of reducing sugar, and the optimal condition for steam explosion is as follows: the pressure is 2.0 MPa, the pressure-retaining time 300 s, the initial acid concentration 1% and the acid treatment time 24 h.

  12. Pretreatment Capabilities and Benefits of Electrocoagulation

    Science.gov (United States)

    2004-12-01

    PRETREATMENT CAPABILITIES AND BENEFITS OF ELECTROCOAGULATION Michael Mickley Mickley & Associates Boulder, Colorado...DATES COVERED - 4. TITLE AND SUBTITLE Pretreatment Capabilities and Benefits of Electrocoagulation 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c...4 2.1 Background for Electrocoagulation Technology ………………………. 4 2.1.1 Applications ……………………………………………………. 4 2.1.2

  13. Possibilities and evaluation of straw pretreatment

    DEFF Research Database (Denmark)

    Knudsen, Niels Ole; Jensen, Peter Arendt; Sander, Bo

    1998-01-01

    Biomass utilisation by cofiring of straw in a pulverised coal fire boiler is economically attractive compared to dedicated straw fired plants. However, the high content of potassium and chloride impedes utilisation of the fly ash, deactivates the de NOx catalysts in the flue gas cleaning system...... and may also lead to increased deposit formation. A pretreatment process is required to solve the problems. In this paper two pretreatment processes are considred, one based on straw wash and another based on pyrolysis and char wash. To evaluate and compare the processes, laboratory and technical...

  14. Technical Basis of Scaling Relationships for the Pretreatment Engineering Platform

    Energy Technology Data Exchange (ETDEWEB)

    Kuhn, William L.; Arm, Stuart T.; Huckaby, James L.; Kurath, Dean E.; Rassat, Scot D.

    2008-07-15

    Pacific Northwest National Laboratory has been tasked by Bechtel National Inc. (BNI) on the River Protection Project-Waste Treatment Plant (RPP-WTP) project to perform research and development activities. The Pretreatment Engineering Platform (PEP) is being designed and constructed as part of a plan to respond to an issue raised by the WTP External Flowsheet Review Team (EFRT) entitled “Undemonstrated Leaching Processes” and numbered M12. The PEP replicates the WTP leaching process using prototypic equipment and control strategies. The approach for scaling PEP performance data to predict WTP performance is critical to the successful resolution of the EFRT issue. This report describes the recommended PEP scaling approach, PEP data interpretation and provides recommendations on test conduct and data requirements.

  15. Simulation of the ozone pretreatment of wheat straw.

    Science.gov (United States)

    Bhattarai, Sujala; Bottenus, Danny; Ivory, Cornelius F; Gao, Allan Haiming; Bule, Mahesh; Garcia-Perez, Manuel; Chen, Shulin

    2015-11-01

    Wheat straw is a potential feedstock in biorefinery for sugar production. However, the cellulose, which is the major source of sugar, is protected by lignin. Ozonolysis deconstructs the lignin and makes cellulose accessible to enzymatic digestion. In this study, the change in lignin concentration with different ozonolysis times (0, 1, 2, 3, 5, 7, 10, 15, 20, 30, 60min) was fit to two different kinetic models: one using the model developed by Garcia-Cubero et al. (2012) and another including an outer mass transfer barrier or "cuticle" region where ozone mass transport is reduced in proportion to the mass of unreacted insoluble lignin in the cuticle. The kinetic parameters of two mathematical models for predicting the soluble and insoluble lignin at different pretreatment time were determined. The results showed that parameters derived from the cuticle-based model provided a better fit to experimental results compared to a model without a cuticle layer.

  16. 胍丁胺对创伤小鼠过度炎症反应及脾细胞增殖的影响%Effects of agmatine on excessive inflammatory reaction and proliferation of splenic cells in mice with trauma

    Institute of Scientific and Technical Information of China (English)

    刘政; 侯凤艳; 靳贺; 肖雅; 范霞; 杨雪; 严军; 梁华平

    2015-01-01

    245.7±22.1比128.2±15.9;ALT(U/L):92.1±6.3、51.6±5.0比30.1±3.2;LDH(U/L):606.7±36.3、478.7±25.3比384.0±16.6;均P<0.01〕;但胍丁胺治疗能明显减少创伤后血清肝酶的活性(均P<0.01)。创伤后24 h,模型组ConA刺激脾细胞增殖能力及其分泌IFN-γ与IL-2的能力均较对照组明显降低〔增殖率:(40.97±4.13)%比(89.99±7.76)%;IFN-γ(ng/L):91.6±12.3比353.2±21.5;IL-2(ng/L):53.4±6.4比91.0±12.2;均P<0.01〕,胍丁胺治疗能明显增强创伤后ConA刺激脾细胞的增殖能力〔增殖率:(74.86±5.75)%比(40.97±4.13)%,P<0.01〕,提高脾细胞分泌IFN-γ与IL-2的能力〔IFN-γ(ng/L):327.8±23.6比91.6±12.3;IL-2(ng/L):74.8±10.4比53.4±6.4;均P<0.01〕。结论胍丁胺能显著改善创伤诱导的脾细胞免疫功能抑制,减轻过度炎症反应和器官功能损害。%ObjectiveTo observe protective effects of agmatine (AGM) on inflammatory response and spleen immune function in mice with trauma.Methods Forty-eight adult male C57BL/6 mice were randomly divided into three groups (n= 16 each), including control group, model group (bilateral femoral fracture and removal of 35% of the total blood volume), and AGM group (trauma/hemorrhage & AGM 200 mg/kg). Eight mice in each group were sacrificed at 3 hours and 24 hours, respectively, after modeling, and blood samples and tissue homogenate of spleen and liver were collected. The contents of tumor necrosis factor-α (TNF-α), interleukins (IL-6, IL-1β) in serum and liver tissue were determined with enzyme linked immunosorbent assay (ELISA). Serum aspartate transaminase (AST), alanine aminotransferase (ALT) and lactic dehydrogenase (LDH) were determined with automatic biochemistry analyzer. Spleen proliferation response stimulated with concanavalin A (ConA) was evaluated with methyl thiazolyl tetrazolium colourimetry (MTT).γ-interferon (IFN-γ) and IL-2 releases were

  17. Pretreatment on Corn Stover with Low Concentration of Formic Acid

    DEFF Research Database (Denmark)

    Xu, Jian; Thomsen, Mette Hedegaard; Thomsen, Anne Belinda

    2009-01-01

    the cellulose easily degraded into sugars and further fermented to ethanol. In this work, hydrothermal pretreatment on corn stover at 195 degrees for 15 min with and without lower concentration of formic acid was compared in terms of sugar recoveries and ethanol fermentation. For pretreatment with formic acid...... pretreatment without formic acid. Toxicity tests of liquor parts showed that there were no inhibitions found for both pretreatment conditions. After simultaneous saccharification and fermentation (SSF) of the pretreated corn stover with Baker's yeast, the highest ethanol yield of 76.5% of the theoretical...... was observed from corn stover pretreated at 195 degrees for 15min with formic acid....

  18. Neuroprotective effect of pretreatment with ganoderma lucidum in cerebral ischemia/reperfusion injur y in rat hippocampus

    Institute of Scientific and Technical Information of China (English)

    Wangxin Zhang; Qiuling Zhang; Wen Deng; Yalu Li; Guoqing Xing; Xianjun Shi; Yifeng Du

    2014-01-01

    Ganoderma lucidum is a traditional Chinese medicine, which has been shown to have both an-ti-oxidative and anti-inlfammatory effects, and noticeably decreases both the infarct area and neuronal apoptosis of the ischemic cortex. This study aimed to investigate the protective effects and mechanisms of pretreatment with ganoderma lucidum (by intragastric administration) in cerebral ischemia/reperfusion injury in rats. Our results showed that pretreatment with ganoder-ma lucidum for 3 and 7 days reduced neuronal loss in the hippocampus, diminished the content of malondialdehyde in the hippocampus and serum, decreased the levels of tumor necrosis fac-tor-αand interleukin-8 in the hippocampus, and increased the activity of superoxide dismutase in the hippocampus and serum. hTese results suggest that pretreatment with ganoderma lucidum was protective against cerebral ischemia/reperfusion injury through its anti-oxidative and an-ti-inlfammatory actions.

  19. Dynamic Modeling and Validation of a Biomass Hydrothermal Pretreatment Process - A Demonstration Scale Study

    DEFF Research Database (Denmark)

    Prunescu, Remus Mihail; Blanke, Mogens; Jakobsen, Jon Geest;

    2015-01-01

    Hydrothermal pretreatment of lignocellulosic biomass is a cost effective technology for second generation biorefineries. The process occurs in large horizontal and pressurized thermal reactors where the biomatrix is opened under the action of steam pressure and temperature to expose cellulose for...... of the process, outlining the value of the model for simulation, control design, and optimization for full-scale applications. This article is protected by copyright. All rights reserved....

  20. 血必净注射液预处理对肝癌切除术后缺血/再灌注损伤及凝血功能紊乱的保护作用研究%The protective effect of Xuebijing injection pretreatment on hepatic ischemia/reperfusion injury and coagulopathy after excision of liver cancer

    Institute of Scientific and Technical Information of China (English)

    沈珏; 林小军; 崔伯康; 池沛冬; 曾秋耀; 赵擎宇

    2013-01-01

    (APACHEⅡ)评分明显低于对照组(分:4.18±3.75比4.53±2.34,t=5.328,P=0.027),术后首次排气、排便时间均明显早于对照组[排气时间(d):3(2~4)比3(2~4),U=-2.023,P=0.043;排便时间(d):4(2~6)比5(3~8),U=-2.926,P=0.003],但术后住院天数和总住院天数比较差异无统计学意义.Spearman秩相关分析显示,乙型肝炎病毒基因(HBV-DNA)阳性的33例患者HBV-DNA水平与术前ALT(r=0.414,P=0.044)、AST(r=0.405,P=0.024)呈明显正相关,与手术前后其他肝功能指标均无明显相关性.结论 入肝血流阻断肝癌切除术可造成一定程度的肝I/R损伤及凝血功能紊乱;血必净注射液可能通过抑制肝脏I/R后炎症因子的释放,减轻肝组织损伤,且对患者术后肠道功能恢复具有促进作用,但对改善凝血功能紊乱的作用不明显.%Objective To observe the protective effect of Xuebijing injection pretreatment on hepatic ischemia/reperfusion (I/R) injury and coagulopathy in liver cancer patients undergoing excision of hepatic cancer after occlusion of hepatic blood flow.Methods A prospective randomly controlled study was conducted.Sixty patients with liver cancer classified as Child-Pugh class A undergoing hepatectomy in the Department of Hepatobiliary Surgery of Sun Yat-sen University Cancer Center from October 2011 to March 2013 were enrolled.The patients were randomized into control group and Xuebijing group (each patient received 100 mL Xuebijing injection added to 0.9% saline as a preoperative treatment for 3 days).Complete blood count,coagulation function,hepatic function,serum pro-inflammatory cytokines and alpha-fetoprotein (AFP) levels were determined before and after operation.Results Forty-five out of 60 patients were enrolled eventually,with 23 patients in control group and 22 in Xuebijing group,and among them 43 patients were positive for hepatitis B surface antigen (HBsAg) at admission.Compared with those before operation,the postoperative levels of alanine

  1. The impacts of pretreatment on the fermentability of pretreated lignocellulosic biomass: a comparative evaluation between ammonia fiber expansion and dilute acid pretreatment

    Directory of Open Access Journals (Sweden)

    Dale Bruce E

    2009-12-01

    Full Text Available Abstract Background Pretreatment chemistry is of central importance due to its impacts on cellulosic biomass processing and biofuels conversion. Ammonia fiber expansion (AFEX and dilute acid are two promising pretreatments using alkaline and acidic pH that have distinctive differences in pretreatment chemistries. Results Comparative evaluation on these two pretreatments reveal that (i AFEX-pretreated corn stover is significantly more fermentable with respect to cell growth and sugar consumption, (ii both pretreatments can achieve more than 80% of total sugar yield in the enzymatic hydrolysis of washed pretreated solids, and (iii while AFEX completely preserves plant carbohydrates, dilute acid pretreatment at 5% solids loading degrades 13% of xylose to byproducts. Conclusion The selection of pretreatment will determine the biomass-processing configuration, requirements for hydrolysate conditioning (if any and fermentation strategy. Through dilute acid pretreatment, the need for hemicellulase in biomass processing is negligible. AFEX-centered cellulosic technology can alleviate fermentation costs through reducing inoculum size and practically eliminating nutrient costs during bioconversion. However, AFEX requires supplemental xylanases as well as cellulase activity. As for long-term sustainability, AFEX has greater potential to diversify products from a cellulosic biorefinery due to lower levels of inhibitor generation and lignin loss.

  2. Electrochemical impedance spectroscopic investigation of the role of alkaline pre-treatment in corrosion resistance of a silane coating on magnesium alloy, ZE41

    Energy Technology Data Exchange (ETDEWEB)

    Chakraborty Banerjee, P. [Department of Chemical Engineering, Monash University, Clayton, VIC-3800 (Australia); CAST Cooperative Research Centre, Hawthorn, VIC-3122 (Australia); Singh Raman, R.K., E-mail: raman.singh@eng.monash.edu.a [Department of Chemical Engineering, Monash University, Clayton, VIC-3800 (Australia); Department of Mechanical and Aerospace Engineering, Monash University, Clayton, VIC-3800 (Australia)

    2011-04-15

    The protective performance of the coatings of bis-1,2-(triethoxysilyl) ethane (BTSE) on ZE41 magnesium alloy with different surface pre-treatments were evaluated using potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) in 0.1 M sodium chloride solution. Electrical equivalent circuits were developed based upon hypothetical corrosion mechanisms and simulated to correspond to the experimental data. The morphology and cross section of the alloy subjected to different pre-treatments and coatings were characterized using scanning electron microscope. A specific alkaline pre-treatment of the substrate prior to the coating has been found to improve the corrosion resistance of the alloy.

  3. Increases of Catalase and Glutathione Peroxidase Expressions by Lacosamide Pretreatment Contributes to Neuroprotection Against Experimentally Induced Transient Cerebral Ischemia.

    Science.gov (United States)

    Choi, Hyun Young; Park, Joon Ha; Chen, Bai Hui; Shin, Bich Na; Lee, Yun Lyul; Kim, In Hye; Cho, Jeong-Hwi; Lee, Tae-Kyeong; Lee, Jae-Chul; Won, Moo-Ho; Ahn, Ji Hyeon; Tae, Hyun-Jin; Yan, Bing Chun; Hwang, In Koo; Cho, Jun Hwi; Kim, Young-Myeong; Kim, Sung Koo

    2016-09-01

    Lacosamide is a new antiepileptic drug which is widely used to treat partial-onset seizures. In this study, we examined the neuroprotective effect of lacosamide against transient ischemic damage and expressions of antioxidant enzymes such as Zn-superoxide dismutase (SOD1), Mn-superoxide dismutase (SOD2), catalase (CAT) and glutathione peroxidase (GPX) in the hippocampal cornu ammonis 1 (CA1) region following 5 min of transient global cerebral ischemia in gerbils. We found that pre-treatment with 25 mg/kg lacosamide protected CA1 pyramidal neurons from transient global cerebral ischemic insult using hematoxylin-eosin staining and neuronal nuclear antigen immunohistochemistry. Transient ischemia dramatically changed expressions of SOD1, SOD2 and GPX, not CAT, in the CA1 pyramidal neurons. Lacosamide pre-treatment increased expressions of CAT and GPX, not SOD1 and 2, in the CA1 pyramidal neurons compared with controls, and their expressions induced by lacosamide pre-treatment were maintained after transient cerebral ischemia. In brief, pre-treatment with lacosamide protected hippocampal CA1 pyramidal neurons from ischemic damage induced by transient global cerebral ischemia, and the lacosamide-mediated neuroprotection may be closely related to increases of CAT and GPX expressions by lacosamide pre-treatment.

  4. β-Caryophyllene Pretreatment Alleviates Focal Cerebral Ischemia-Reperfusion Injury by Activating PI3K/Akt Signaling Pathway.

    Science.gov (United States)

    Zhang, Qian; An, Ruidi; Tian, Xiaocui; Yang, Mei; Li, Minghang; Lou, Jie; Xu, Lu; Dong, Zhi

    2017-02-24

    β-Caryophyllene (BCP) has been reported to be protective against focal cerebral ischemia-reperfusion (I/R) injury by its anti-oxidative and anti-inflammatory features. Recent study demonstrates that the BCP exhibits potential neuroprotection against I/R injury induced apoptosis, however, the mechanism remains unknown. Therefore, we investigate the underlying anti-apoptotic mechanism of BCP pretreatment in I/R injury. Sprague-Dawley rats (pretreated with BCP suspensions or solvent orally for 7 days) were subjected to transient Middle Cerebral Artery Occlusion (MCAO) for 90 min, followed by 24 h reperfusion. Results showed that BCP pretreatment improved the neurologic deficit score, lowered the infarct volume and decreased number of apoptotic cells in the hippocampus. Moreover, in western blot and RT-qPCR detections, BCP pretreatment down-regulated the expressions of Bax and p53, up-regulated the expression of Bcl-2, and enhanced the phosphorylation of Akt on Ser473. Blockage of PI3K activity by wortmannin not only abolished the BCP-induced decreases in infarct volume and neurologic deficit score, but also dramatically abrogated the enhancement of AKt phosphorylation. Our results suggested that BCP pre-treatment protects against I/R injury partly by suppressing apoptosis via PI3K/AKt signaling pathway activation.

  5. Fuel ethanol production from corn stover under optimized dilute phosphoric acid pretreatment and enzymatic hydrolysis

    Science.gov (United States)

    Ethanol is a renewable oxygenated fuel. Dilute acid pretreatment is a promising pretreatment technology for conversion of lignocellulosic biomass to fuel ethanol. Generation of fermentable sugars from corn stover involves pretreatment and enzymatic saccharification. Pretreatment is crucial as nat...

  6. Evaluation of the Antidepressant Effect of Agmatine in Pharmacological Depression Models%胍丁胺在药物诱发抑郁模型上的药效评价

    Institute of Scientific and Technical Information of China (English)

    龚正华; 李云峰; 罗质璞; 李锦

    2005-01-01

    目的在药物诱发抑郁模型上观察胍丁胺(Agmatine,AG)的抗抑郁作用及可能的作用机制.方法采用小鼠5-羟色胺酸(5-hydroxytryptophan,5-HTP)增强实验,小鼠育亨宾(yohimbine,YOH)毒性增强实验,小鼠阿朴吗啡(apomorphine,APO)诱导体温下降和利血平(reserpine,RES)诱导体温下降实验探讨AG抗抑郁作用及可能的作用环节.用VIDEOMEX-V型图像运动解析仪检测小鼠自发活动行为.结果在小鼠5-HTP增强实验模型上,单次ig给予AG 10~20mg*kg-1剂量,或多次ig给予AG 10~80mg*kg-1(qd,连续3d),对5-HTP诱导的小鼠甩头行为均具有显著增强作用.在小鼠YOH毒性增强实验模型上,多次ig给予AG 10~160mg*kg-1(qd,连续3d),均未见增强YOH毒性作用.在小鼠APO诱导体温下降实验模型上,ig给予AG 10~80mg*kg-1(qd,连续7d),对APO 16mg*kg-1诱导的降温和AUC0~30均未见显著性的拮抗作用.在小鼠RES诱导体温下降实验模型上,ig给予AG 10~80mg*kg-1(qd,连续7d),对RES 1mg*kg-1诱导的降温和AUC0~6均有显著的拮抗作用.小鼠ig给予AG 10~80mg*kg-1(qd,连续3d)对自发活动无显著性改变.结论 AG在药理学抑郁模型有显著的抗抑郁活性.并且其抗抑郁活性与增强5-羟色胺(5-HT)神经系统功能有关,而与去甲肾上腺素能(NE)神经功能无关.AG在抗抑郁有效剂量范围内无中枢兴奋或抑制性作用.

  7. Influences of mechanical pretreatment on the non-biological treatment of municipal wastewater by forward osmosis.

    Science.gov (United States)

    Hey, Tobias; Zarebska, Agata; Bajraktari, Niada; Vogel, Jörg; Hélix-Nielsen, Claus; la Cour Jansen, Jes; Jönsson, Karin

    2016-11-24

    Municipal wastewater treatment involves mechanical, biological and chemical treatment steps for protecting the environment from adverse effects. The biological treatment step consumes the most energy and can create greenhouse gases. This study investigates municipal wastewater treatment without the biological treatment step, including the effects of different pretreatment configurations, for example, direct membrane filtration before forward osmosis. Forward osmosis was tested using raw wastewater and wastewater subjected to different types of mechanical pretreatment, for example, microsieving and microfiltration permeation, as a potential technology for municipal wastewater treatment. Forward osmosis was performed using Aquaporin Inside™ and Hydration Technologies Inc. (HTI) membranes with NaCl as the draw solution. Both types of forward osmosis membranes were tested in parallel for the different types of pretreated feed and evaluated in terms of water flux and solute rejection, that is, biochemical oxygen demand (BOD7) and total and soluble phosphorus contents. The Aquaporin and HTI membranes achieved a stable water flux with rejection rates of more than 96% for BOD7 and total and soluble phosphorus, regardless of the type of mechanical pretreated wastewater considered. This result indicates that forward osmosis membranes can tolerate exposure to municipal waste water and that the permeate can fulfil the Swedish discharge limits.

  8. Strategies of xylanase supplementation for an efficient saccharification and cofermentation process from pretreated wheat straw.

    Science.gov (United States)

    Alvira, Pablo; Tomás-Pejó, Elia; Negro, María José; Ballesteros, Mercedes

    2011-07-01

    Ethanol production from lignocellulosic raw materials includes a pretreatment step before enzymatic hydrolysis (EH). Pretreated substrates contain complex hemicelluloses in the solid fraction that can protect the cellulose from enzymatic attack. In addition, soluble xylooligomers are contained in the pretreated materials and may have an inhibitory effect on cellulase activity. In this context, several approaches for xylanase supplementation have been studied to increase EH yields. In this study, the whole slurry obtained after steam explosion pretreatment of wheat straw has been used as substrate. EH experiments were performed using commercial cellulase preparations supplemented with an endoxylanase (XlnC) from Aspergillus nidulans. Among different strategies of XlnC supplementation, the 24-h xylanase treatment before cellulase addition yielded an increase of 40.1 and 10.1% in glucose and xylose production, respectively. Different XlnC addition strategies were integrated in a simultaneous saccharification and cofermentation process (SSCF) using the xylose fermenting strain Saccharomyces cerevisiae F12. Ethanol production in SSCF was 28.4% higher when comparing to a simultaneous saccharification and fermentation process.

  9. Pretreatment of Latent Prints for Laser Development.

    Science.gov (United States)

    Menzel, E R

    1989-06-01

    The pretreatment procedures for laser detection of latent fingerprints is reviewed. The general features of laser detection and the operational aspects of the examination of physical evidence for laser fingerprint detection are enumerated in the initial sections. The literature review is divided into various pretreatment approaches. Cited studies prior to 1981 are primarily concerned with the demonstration of the viability of laser fingerprint detection, whereas work post-1981 addresses issues of compatibility with the traditional methods of fingerprint development, examination of difficult surfaces, and the routine implementation of laser detection by law enforcement agencies. Related topics of research, review articles, conference reports, case examinations, the research support climate, and future trends are also briefly addressed.

  10. Pretreatment of Dioscorea zingiberensis for Microbial Transformation

    Directory of Open Access Journals (Sweden)

    Tianxiang Zheng

    2014-09-01

    Full Text Available The influences of five pretreatments on fungal growth and enzyme production during microbial transformation of Dioscorea zingiberensis (DZW were studied. The biomass, α-rhamnase and β-glucosidase activities in the fermentation system were employed in the study to determine how each method affected the efficiency of microbial transformation. The fungal strain grew better on the substrate which contained easily utilized carbon source. While lack of carbon source induced the strain produce more glucosidase. Among five pretreatment methods, complex enzymatic hydrolyzation can remove 84.3% starch and 76.5% fibre from DZW in form of sugar, which resulted in high α-rhamnase activity of 2.89 IU/mL and β-glucosidase activity of 8.17 IU/mL in fermentation broth.

  11. Biological pretreatment of Yellow River water

    Institute of Scientific and Technical Information of China (English)

    XIE Shu-guang; TANG Xiao-yan; WU Wei-zhong; WEN Dong-hui; WANG Zhan-sheng

    2005-01-01

    Bio-ceramic filter(BF) and moving-bed biofilm reactor(MBBR) were used for biological pretreatment of Yellow River water in this study. The BF only had slight advantage over MBBR for TOC and ammonia removal. However, like UV254, the average removal rate of THMFP in the BF was much higher than that in the MBBR. UV254 removal did not show obvious correlation with trihalomethane formation potential(THMFP) removal. Hexachlorocyclohexane could be effectively removed in both BF and MBBR. As for diatom and cyanobateria removal the MBBR had better performance than the BF, which was contrary to the average chlorophyll-a (Chi-a) removal rate. The proposal was made in this study that biological flocculation and sedimentation of sloughed biofilm should play a more important role on algae removal in the MBBR than in the BF. The BF and MBBR could effectively remove microcystins. Moreover, MBBR could be a promising technology for biological pretreatment.

  12. Waste Separations and Pretreatment Workshop report

    Energy Technology Data Exchange (ETDEWEB)

    Cruse, J.M. [Westinghouse Hanford Co., Richland, WA (United States); Harrington, R.A. [Kaiser Engineers Hanford Co., Richland, WA (United States); Quadrel, M.J. [Battelle Pacific Northwest Lab., Richland, WA (United States)

    1994-01-01

    This document provides the minutes from the Waste Separations and Pretreatment Workshop sponsored by the Underground Storage Tank-Integrated Demonstration in Salt Lake City, Utah, February 3--5, 1993. The Efficient Separations and Processing-Integrated Program and the Hanford Site Tank Waste Remediation System were joint participants. This document provides the detailed minutes, including responses to questions asked, an attendance list, reproductions of the workshop presentations, and a revised chart showing technology development activities.

  13. Evaluation of high solids alkaline pretreatment of rice straw.

    Science.gov (United States)

    Cheng, Yu-Shen; Zheng, Yi; Yu, Chao Wei; Dooley, Todd M; Jenkins, Bryan M; VanderGheynst, Jean S

    2010-11-01

    Fresh-harvested, air-dried rice straw was pretreated at a water content of 5 g H(2)O/g straw using sodium hydroxide (NaOH) and compared to pretreatment at 10 g H(2)O/g straw by hydrated lime (Ca(OH)(2)). Full factorial experiments including parallel wash-only treatments were completed with both sources of alkali. The experiments were designed to measure the effects of alkaline loading and pretreatment time on delignification and sugar yield upon enzymatic hydrolysis. Reaction temperature was held constant at 95 degrees C for lime pretreatment and 55 degrees C for NaOH pretreatment. The range of delignification was 13.1% to 27.0% for lime pretreatments and was 8.6% to 23.1% for NaOH pretreatments. Both alkaline loading and reaction time had significant positive effects (p pretreatment at 95 degrees C, but there was little effect observed at 55 degrees C. Post-pretreatment washing of biomass was not necessary for subsequent enzymatic hydrolysis. Maximum glucose yields were 176.3 mg/g dried biomass (48.5% conversion efficiency of total glucose) in lime-pretreated and unwashed biomass and were 142.3 mg/g dried biomass (39.2% conversion efficiency of total glucose) in NaOH-pretreated and unwashed biomass.

  14. Pretreatment of Agave americana stalk for enzymatic saccharification.

    Science.gov (United States)

    Yang, Qiang; Pan, Xuejun

    2012-12-01

    Agave americana is one of commonly grown agave species but currently less valuable because its large flower stalk cannot be used for producing alcoholic beverage. In the present study, the stalk was pretreated with dilute acid (DA), sulfite (SPORL), and sodium hydroxide (NaOH) to preliminarily assess its potential as feedstock for bioethanol production. The changes of cell wall components during the pretreatments, enzymatic digestibility of the pretreated stalks, and the adsorption of cellulases on the substrates were investigated. Results indicated that the pretreatments significantly improved the enzymatic digestibility of the agave stalk. SPORL pretreatment gave higher substrate and sugar yields, while NaOH pretreated stalk had better digestibility under the investigated conditions. The better hydrolysability of NaOH-pretreated stalk was attributed to low lignin and hemicellulose content and high affinity to cellulases.

  15. Hydrolyzabilities of different corn stover fractions after aqueous ammonia pretreatment.

    Science.gov (United States)

    Sun, Zongping; Ge, Xiaoyan; Xin, Donglin; Zhang, Junhua

    2014-02-01

    The effect of aqueous ammonia pretreatment on the hydrolysis of different corn stover fractions (rind, husk, leaf, and pith) by xylanase (XYL) with cellulases (CELs) was evaluated. The aqueous ammonia pretreatment had excellent delignification ability (above 66%) for different corn stover fractions. The corn rind exhibited the lowest susceptibility to aqueous ammonia pretreatment. The pretreated rind showed the lowest hydrolyzability by CEL and XYL, which was supported by a high content of crystalline cellulose in the hydrolyzed residues of rind, as confirmed by X-ray diffraction (XRD). With the addition of 1 mg XYL/g dry matter, a high glucose yield (above 90%) could be obtained from the pretreated rind by CEL. The results revealed that a high hydrolyzate yield of corn rind after aqueous ammonia pretreatment could be obtained with 1 mg xylanase/g dry matter, showing that aqueous ammonia pretreatment and xylanase addition to cellulases have great potential for the efficient hydrolysis of corn stover without previous fractionation.

  16. Hydrothermal pretreatment of palm oil empty fruit bunch

    Science.gov (United States)

    Simanungkalit, Sabar Pangihutan; Mansur, Dieni; Nurhakim, Boby; Agustin, Astrid; Rinaldi, Nino; Muryanto, Fitriady, Muhammad Ariffudin

    2017-01-01

    Hydrothermal pretreatment methods in 2nd generation bioethanol production more profitable to be developed, since the conventional pretreatment, by using acids or alkalis, is associated with the serious economic and environmental constraints. The current studies investigate hydrothermal pretreatment of palm oil empty fruit bunch (EFB) in a batch tube reactor system with temperature and time range from 160 to 240 C and 15 to 30 min, respectively. The EFB were grinded and separated into 3 different particles sizes i.e. 10 mesh, 18 mesh and 40 mesh, prior to hydrothermal pretreatment. Solid yield and pH of the treated EFB slurries changed over treatment severities. The chemical composition of EFB was greatly affected by the hydrothermal pretreatment especially hemicellulose which decreased at higher severity factor as determined by HPLC. Both partial removal of hemicellulose and migration of lignin during hydrothermal pretreatment caused negatively affect for enzymatic hydrolysis. This studies provided important factors for maximizing hydrothermal pretreatment of EFB.

  17. Recyclability of an ionic liquid for biomass pretreatment.

    Science.gov (United States)

    Weerachanchai, Piyarat; Lee, Jong-Min

    2014-10-01

    This study investigated the possibility of reusing an ionic liquid for the pretreatment of biomass. The effects of lignin and water content in a pretreatment solvent on pretreatment products were examined, along with the recyclability of an ionic liquid for pretreatment. It was discovered that the presence of lignin and water within a pretreatment solvent resulted in a far less effective pretreatment process. 1-Ethyl-3-methylimidazolium acetate/ethanolamine (60/40 vol%) presents more promising properties than EMIM-AC, providing a small decrease in sugar conversion and also a small increase of lignin deposition with an increasing lignin amount in the pretreatment solvent. Deteriorations of the ionic liquid were observed from considerably low sugar conversions and lignin extraction after using the 5th and 7th batch, respectively. Furthermore, the changes of ionic liquid properties and lignin accumulation in ionic liquid were determined by analyzing their thermal decomposition behavior (TGA) and chemical functional groups (FTIR and (1)H NMR).

  18. Effects of Acupuncture Pretreatment on Ischemic Cardiac Muscle Cell Apoptosis and Gene Expression in Ischemia-reperfusion Rats

    Institute of Scientific and Technical Information of China (English)

    赵宇辉; 孙忠人; 崔学军

    2009-01-01

    目的:针灸预处理对缺血心肌具有保护作用.通过观察针刺预处理对心肌缺血再灌注损伤大鼠心肌细胞凋亡及HSP70mPNA表达的影响,探讨针刺预处理的心肌保护机制.方法:64只Wistar大鼠随机分为8组,即正常对照组,假手术组,缺血再灌注组,缺血预处理组,手捻针预处理日1次组,电针预处理日1次组,手捻针预处理日2次组,电针预处理日2次组.建立大鼠心肌缺血再灌注模型,采用原位杂交法测定心肌HSP70mRNA的表达,TUNEL法检测细胞凋亡.结果:与正常对照组、假手术组比较,缺血再灌注组细胞凋亡增加,HSP70 mRNA表达增加;与缺血再灌注组比较,针刺预处理使心肌细胞凋亡减少、HSP70mRNA表达增加,且针刺预处理日2次组作用强于针刺预处理日1次组和缺血预处理组.结论:针刺预处理能够抑制心肌缺血再灌注损伤大鼠心肌细胞凋亡,上调心肌HSP70mRNA的表达.针刺预处理每日2次的作用强于针剌预处理每日1次.%Objective:To investigate the protective effects of acupuncture pretreatment on ischemic myocardium,the protective mechanism of acupuncture pretreatment on ischemic myocardium was explored by observing the cardiac muscle cell apoptosis and the expression of HSP70 mRNA of ischemia-reperfusion injury rats treated with acupuncture pretreatment.Methods:Sixty-four Wistar rats were randomly divided into eight groups:control group,sham surgery group,ischemia-repertusion group,ischemia pretreatment group,manual acupuncture pretreatment group(once a day),electroacupuncture pretreatment group(once a day),manual acupuncture pretreatment group(twice a day),and electroacupuncture pretreatment group(twice a day).The reperfusion model of rat myocardial ischemia was made.Expression of HSP70 mRNA was assayed by in situ hyrbridization,and cell apoptosis by TUNEL.Results:Compared with those in the control group and the sham surgery group,the apoptosis and the expression of HSP70 m

  19. The protective effect of endotoxin pretreatment on lung injury induced by hepatic ischemia reperfusion in rabbits%内毒素预处理对兔肝脏缺血-再灌注后肺损伤的保护效应

    Institute of Scientific and Technical Information of China (English)

    葛云洁; 王野; 张淑立; 赵伟业; 鲁德忱; 玛黎清

    2008-01-01

    Objective To investite the effect of endotoxin pretreatment on lung injury induced by hepatic ischemia reperfusion in rabbits and its mechanism. Method Forty-eight New Zealand white rabbits were randomly divided into4 groups with 12 rabbits each group:routine control group,pretreatment control group,ischemia reperfusion group (IR group), and preperfusion group( LPS + IR group). Rabbits of routine control group received operative dissector only, and those of pretreatment control group received pretratment of daily intraabdominal injection of lipopo|ysaccharide(O.5,0.5,and 1.0 mg/kg,respectively)in the 3 days before operative dissector.Livers of IR group were rendered and ischeraic for 30 minutes, and repeffused for up to 4 hours. Rabbits of LPS +IR group received the preueaunent before heretic ischemia repeffusion. Four hours after reperfusion, serum endotoxin,tumor necrosis factor-α(TNF-α), wet/dry ratio and broncho-alveolar lavage fluid protein content of lung,malondialdehyde(MDA) and mpenrxide dismutase(SOD) in lung homogenate, lung injury ratio, and activity of Nuclear factor-kB(NF-kB) in alveolar macrophage wene examined. Differences within the groups were analyzed using One way ANOVA. Results Between the two control groups,there were no significant differences in all indexes(P>0.05). The TNF-α[ (48.31±5.31)pg/ml vs.(56.47±5.09)pg/ml, P0.05).LPS+IR组血清TNF-α[(48.31±5.31)pg/ml vs.(56.47±5.09)pg/ml,P<0.01]、肺湿干比[(4.98±0.33)vs.(5.22±0.31),P=0.03]、灌洗液蛋白含量[(0.68±0.11)g/L vs.(0.76±0.10)g/L,P:0.04]、MDA[(0.86±0.06)mnol/mg vs.(0.93±0.07)nmoL/mg,P=0.02]、肺损伤率[(13.4±4.3)%vs.(17.4±4.1)%,P=0.03]及肺泡巨噬细胞NF-kB活性[(5.82±1.12)OD/m2 vs.(7.40±1.26)OD/mm2,P<0.01]明显低于IR组;同时LPS+IR组SOD[(90.30±7.38)U/mg vs.(84.44±7.90)U/mg,P=0.04]明显高于IR组.结论 内毒素预处理可以减轻肝脏缺血.再灌注后肺损伤,其机制与降低了血清TNF-α产生及抑制肺泡巨噬细胞中NF-kB活化有关.

  20. Application of high throughput pretreatment and co-hydrolysis system to thermochemical pretreatment. Part 2: Dilute alkali.

    Science.gov (United States)

    Li, Hongjia; Gao, Xiadi; Demartini, Jaclyn D; Kumar, Rajeev; Wyman, Charles E

    2013-11-01

    High throughput pretreatment (HTPH) and enzymatic hydrolysis systems are now vital for screening large numbers of biomass samples to investigate biomass recalcitrance over various pretreatment and enzymatic hydrolysis conditions. Although hydrothermal pretreatment is currently being employed in most high throughput applications, thermochemical pretreatment at low and high pH conditions can offer additional insights to better understand the roles of hemicellulose and lignin, respectively, in defining biomass recalcitrance. Thus, after successfully applying the HTPH approach to dilute acid pretreatment [Gao et al. (2012) Biotechnol. Bioeng. 110(3): 754-762], extension to dilute alkali pretreatment was also achieved using a similar single-step neutralization and buffering concept. In the latter approach, poplar and switchgrass were pretreated with 1 wt% sodium hydroxide at 120°C for different reaction times. Following pretreatment, an H₂Cit⁻/HCit²⁻ buffer with a pH of 4.5 was used to condition the pretreatment slurry to a pH range of 4.69-4.89, followed by enzymatic hydrolysis for 72 h of the entire mixture. Sugar yields showed different trends for poplar and switchgrass with increases in pretreatment times, demonstrating the method provided a clearly discernible screening tool at alkali conditions. This method was then applied to selected Populus tremuloides samples to follow ring-by-ring sugar release patterns. Observed variations were compared to results from hydrothermal pretreatments, providing new insights in understanding the influence of biomass structural differences on recalcitrance.

  1. Pretreatment of the macroalgae Chaetomorpha linum for the production of bioethanol--comparison of five pretreatment technologies.

    Science.gov (United States)

    Schultz-Jensen, Nadja; Thygesen, Anders; Leipold, Frank; Thomsen, Sune Tjalfe; Roslander, Christian; Lilholt, Hans; Bjerre, Anne Belinda

    2013-07-01

    A qualified estimate for pretreatment of the macroalgae Chaetomorpha linum for ethanol production was given, based on the experience of pretreatment of land-based biomass. C. linum was subjected to hydrothermal pretreatment (HTT), wet oxidation (WO), steam explosion (STEX), plasma-assisted pretreatment (PAP) and ball milling (BM), to determine effects of the pretreatment methods on the conversion of C. linum into ethanol by simultaneous saccharification and fermentation (SSF). WO and BM showed the highest ethanol yield of 44 g ethanol/100g glucan, which was close to the theoretical ethanol yield of 57 g ethanol/100g glucan. A 64% higher ethanol yield, based on raw material, was reached after pretreatment with WO and BM compared with unpretreated C. linum, however 50% of the biomass was lost during WO. Results indicated that the right combination of pretreatment and marine macroalgae, containing high amounts of glucan and cleaned from salts, enhanced the ethanol yield significantly.

  2. Pretreatment with low doses of acenocoumarol inhibits the development of acute ischemia/reperfusion-induced pancreatitis.

    Science.gov (United States)

    Warzecha, Z; Sendur, P; Ceranowicz, P; Dembinski, M; Cieszkowski, J; Kusnierz-Cabala, B; Tomaszewska, R; Dembinski, A

    2015-10-01

    Coagulative disorders are known to occur in acute pancreatitis and are related to the severity of this disease. Various experimental and clinical studies have shown protective and therapeutic effect of heparin in acute pancreatitis. Aim of the present study was to determine the influence of acenocoumarol, a vitamin K antagonist, on the development of acute pancreatitis. Studies were performed on male Wistar rats weighing 250 - 270 g. Acenocoumarol at the dose of 50, 100 or 150 μg/kg/dose or vehicle were administered once a day for 7 days before induction of acute pancreatitis. Acute pancreatitis was induced in rats by pancreatic ischemia followed by reperfusion. The severity of acute pancreatitis was assessed after 5-h reperfusion. Pretreatment with acenocoumarol given at the dose of 50 or 100 μg/kg/dose reduced morphological signs of acute pancreatitis. These effects were accompanied with a decrease in the pancreatitis-evoked increase in serum activity of lipase and serum concentration of pro-inflammatory interleukin-1β. Moreover, the pancreatitis-evoked reductions in pancreatic DNA synthesis and pancreatic blood flow were partially reversed by pretreatment with acenocoumarol given at the dose of 50 and 100 μg/kg/dose. Administration of acenocoumarol at the dose of 150 μg/kg/dose did not exhibit any protective effect against ischemia/reperfusion-induced pancreatitis. We concluded that pretreatment with low doses of acenocoumarol reduces the severity of ischemia/reperfusion-induced acute pancreatitis.

  3. Pretreatment of Reed by Wet Oxidation and Subsequent Utilization of the Pretreated Fibers for Ethanol Production

    DEFF Research Database (Denmark)

    Szijarto, Nora; Kádár, Zsófia; Varga, Eniko

    2009-01-01

    lignocelluloses usually do. In the present study, wet oxidation was investigated as the pretreatment method to enhance the enzymatic digestibility of reed cellulose to soluble sugars and thus improve the convertibility of reed to ethanol. The most effective treatment increased the digestibility of reed cellulose...... by cellulases more than three times compared to the untreated control. During this wet oxidation, 51.7% of the hemicellulose and 58.3% of the lignin were solubilized, whereas 87.1% of the cellulose remained in the solids. After enzymatic hydrolysis of pretreated fibers from the same treatment, the conversion......Common reed (Phragmites australis) is often recognized as a promising source of renewable energy. However, it is among the least characterized crops from the bioethanol perspective. Although one third of reed dry matter is cellulose, without pretreatment, it resists enzymatic hydrolysis like...

  4. Sun Protection

    Science.gov (United States)

    ... 100% UV ray protection (look for models that advertise both UVB and UVA protection). Use a broad- ... feeds Follow FDA on Twitter Follow FDA on Facebook View FDA videos on YouTube View FDA photos ...

  5. CORROSION RESISTANCE OF HOT DIP GALVANIZED STEEL PRETREATED WITH BIS-FUNCTIONAL SILANES MODIFIED WITH NANOALUMINA

    Institute of Scientific and Technical Information of China (English)

    F.J.Shan; C.S.Liu; S.H.Wang; G.C.Qi

    2008-01-01

    The corrosion behavior of hot dip galvanized steel pretreated with bis-[triethoxy-silylpropyl]tetrasulfide (BTESPT) modified with alumina particles was studied.The corrosion resistance of the passiving films was evaluated by Tafel polarization curve and electrochemical impedance spectroscopy.The films formed on the galvanized steel substrate were characterized by Fourier transform infrared spectroscopy and energy dispersive X-ray spectrometry.The surface morphology of the treated hot dip galva-nized steel samples was observed by Field Emission Scanning Electron Microscope. The results show that the pretreatments on the basis of silane films modified with nanoalumina particles have reduced both anodic and cathodic current densities,and increased total impedance in the measured frequency,consequently,improving cor-rosion protection for hot dip galvanized steel during immersion in NaCl solutions compared to chromate films and silane films.

  6. Influence of pretreatment of carbamates on dynamic pulmonary mechanics in rats exposed to sarin aerosols.

    Science.gov (United States)

    Husain, K; Kumar, P; Vijayaraghavan, R; Singh, R; Das Gupta, S

    1993-07-01

    The effect of pretreatment of two carbamates, pyridostigmine and physostigmine on dynamic pulmonary mechanics has been studied in rats exposed to sarin aerosols. Sign-free dose of pyridostigmine (0.075 mg/kg, i.m.) or physostigmine (0.1 mg/kg, i.m.) did not significantly alter the parameters of the dynamic pulmonary mechanics 20 min after treatment. However, sarin (51.2 mg/m3, for 15 min) depressed the respiratory rate, air flow and minute volume and enhanced the transthoracic pressure and tidal volume. Pretreatment with carbamates 20 min prior to sarin exposure significantly modified or counteracted the above induced changes. It is concluded that the protective effect of carbamates is mainly due to the correction of respiratory changes caused by sarin aerosols in rats.

  7. Enzymatic Hydrolysis of Alkaline Pretreated Coconut Coir

    Directory of Open Access Journals (Sweden)

    Akbarningrum Fatmawati

    2013-06-01

    Full Text Available The purpose of this research is to study the effect of concentration and temperature on the cellulose and lignin content, and the reducing sugars produced in the enzymatic hydrolysis of coconut coir. In this research, the coconut coir is pretreated using 3%, 7%, and 11% NaOH solution at 60oC, 80oC, and 100oC. The pretreated coir were assayed by measuring the amount of cellulose and lignin and then hydrolysed using Celluclast and Novozyme 188 under various temperature (30oC, 40oC, 50oC and pH (3, 4, 5. The hydrolysis results were assayed for the reducing sugar content. The results showed that the alkaline delignification was effective to reduce lignin and to increase the cellulose content of the coir. The best delignification condition was observed at 11% NaOH solution and 100oC which removed 14,53% of lignin and increased the cellulose content up to 50,23%. The best condition of the enzymatic hydrolysis was obtained at 50oC and pH 4 which produced 7,57 gr/L reducing sugar. © 2013 BCREC UNDIP. All rights reservedReceived: 2nd October 2012; Revised: 31st January 2013; Accepted: 6th February 2013[How to Cite: Fatmawati, A., Agustriyanto, R., Liasari, Y. (2013. Enzymatic Hydrolysis of Alkaline Pre-treated Coconut Coir. Bulletin of Chemical Reaction Engineering & Catalysis, 8 (1: 34-39 (doi:10.9767/bcrec.8.1.4048.34-39[Permalink/DOI: http://dx.doi.org/10.9767/bcrec.8.1.4048.34-39] | View in  |

  8. Surface pretreatments for medical application of adhesion

    Directory of Open Access Journals (Sweden)

    Weber Michael

    2003-09-01

    Full Text Available Abstract Medical implants and prostheses (artificial hips, tendono- and ligament plasties usually are multi-component systems that may be machined from one of three material classes: metals, plastics and ceramics. Typically, the body-sided bonding element is bone. The purpose of this contribution is to describe developments carried out to optimize the techniques , connecting prosthesis to bone, to be joined by an adhesive bone cement at their interface. Although bonding of organic polymers to inorganic or organic surfaces and to bone has a long history, there remains a serious obstacle in realizing long-term high-bonding strengths in the in vivo body environment of ever present high humidity. Therefore, different pretreatments, individually adapted to the actual combination of materials, are needed to assure long term adhesive strength and stability against hydrolysis. This pretreatment for metal alloys may be silica layering; for PE-plastics, a specific plasma activation; and for bone, amphiphilic layering systems such that the hydrophilic properties of bone become better adapted to the hydrophobic properties of the bone cement. Amphiphilic layering systems are related to those developed in dentistry for dentine bonding. Specific pretreatment can significantly increase bond strengths, particularly after long term immersion in water under conditions similar to those in the human body. The bond strength between bone and plastic for example can be increased by a factor approaching 50 (pealing work increasing from 30 N/m to 1500 N/m. This review article summarizes the multi-disciplined subject of adhesion and adhesives, considering the technology involved in the formation and mechanical performance of adhesives joints inside the human body.

  9. Pretreatment and enzymatic hydrolysis of lignocellulosic biomass

    Science.gov (United States)

    Corredor, Deisy Y.

    The performance of soybean hulls and forage sorghum as feedstocks for ethanol production was studied. The main goal of this research was to increase fermentable sugars' yield through high-efficiency pretreatment technology. Soybean hulls are a potential feedstock for production of bio-ethanol due to their high carbohydrate content (≈50%) of nearly 37% cellulose. Soybean hulls could be the ideal feedstock for fuel ethanol production, because they are abundant and require no special harvesting and additional transportation costs as they are already in the plant. Dilute acid and modified steam-explosion were used as pretreatment technologies to increase fermentable sugars yields. Effects of reaction time, temperature, acid concentration and type of acid on hydrolysis of hemicellulose in soybean hulls and total sugar yields were studied. Optimum pretreatment parameters and enzymatic hydrolysis conditions for converting soybean hulls into fermentable sugars were identified. The combination of acid (H2SO4, 2% w/v) and steam (140°C, 30 min) efficiently solubilized the hemicellulose, giving a pentose yield of 96%. Sorghum is a tropical grass grown primarily in semiarid and dry parts of the world, especially in areas too dry for corn. The production of sorghum results in about 30 million tons of byproducts mainly composed of cellulose, hemicellulose, and lignin. Forage sorghum such as brown midrib (BMR) sorghum for ethanol production has generated much interest since this trait is characterized genetically by lower lignin concentrations in the plant compared with conventional types. Three varieties of forage sorghum and one variety of regular sorghum were characterized and evaluated as feedstock for fermentable sugar production. Fourier transform infrared spectroscopy (FTIR), scanning electron microscope (SEM) and X-Ray diffraction were used to determine changes in structure and chemical composition of forage sorghum before and after pretreatment and enzymatic hydrolysis

  10. Optimization of alkaline sulfite pretreatment and comparative study with sodium hydroxide pretreatment for improving enzymatic digestibility of corn stover.

    Science.gov (United States)

    Liu, Huan; Pang, Bo; Wang, Haisong; Li, Haiming; Lu, Jie; Niu, Meihong

    2015-04-01

    In this study, alkaline sulfite pretreatment of corn stover was optimized. The influences of pretreatments on solid yield, delignification, and carbohydrate recovery under different pretreatment conditions and subsequent enzymatic hydrolysis were investigated. The effect of pretreatment was evaluated by enzymatic hydrolysis efficiency and the total sugar yield. The optimum pretreatment conditions were obtained, as follows: the total titratable alkali (TTA) of 12%, liquid/solid ratio of 6:1, temperature of 140 °C, and holding time of 20 min. Under those conditions, the solid yield was 55.24%, and the removal of lignin was 82.68%. Enzymatic hydrolysis rates of glucan and xylan for pretreated corn stover were 85.38% and 70.36%, and the total sugar yield was 74.73% at cellulase loading of 20 FPU/g and β-glucosidase loading of 10 IU/g for 48 h. Compared with sodium hydroxide pretreatment with the same amount of total titratable alkali, the total sugar yield was raised by about 10.43%. Additionally, the corn stover pretreated under the optimum pretreatment conditions was beaten by PFI at 1500 revolutions. After beating, enzymatic hydrolysis rates of glucan and xylan were 89.74% and 74.06%, and the total sugar yield was 78.58% at the same enzymatic hydrolysis conditions. Compared with 1500 rpm of PFI beating after sodium pretreatment with the same amount of total titratable alkali, the total sugar yield was raised by about 14.05%.

  11. Comprehensive utilization of glycerol from sugarcane bagasse pretreatment to fermentation.

    Science.gov (United States)

    Jiang, Liqun; Zheng, Anqing; Zhao, Zengli; He, Fang; Li, Haibin

    2015-11-01

    In this study, the effects of glycerol pretreatment on subsequent glycerol fermentation and biomass fast pyrolysis were investigated. The liquid fraction from the pretreatment process was evaluated to be feasible for fermentation by Paenibacillus polymyxa and could be an economic substrate. The pretreated biomass was further utilized to obtain levoglucosan by fast pyrolysis. The pretreated sugarcane bagasse exhibited significantly higher levoglucosan yield (47.70%) than that of un-pretreated sample (11.25%). The promotion could likely be attributed to the effective removal of alkali and alkaline earth metals by glycerol pretreatment. This research developed an economically viable manufacturing paradigm to utilize glycerol comprehensively and enhance the formation of levoglucosan effectively from lignocellulose.

  12. Hydrothermal pretreatment conditions to enhance ethanol production from poplar biomass.

    Science.gov (United States)

    Negro, Maria José; Manzanares, Paloma; Ballesteros, Ignacio; Oliva, Jose Miguel; Cabañas, Araceli; Ballesteros, Mercedes

    2003-01-01

    Pretreatment has been recognized as a key step in enzyme-based conversion processes of lignocellulose biomass to ethanol. The aim of this study is to evaluate two hydrothermal pretreatments (steam explosion and liquid hot water) to enhance ethanol production from poplar (Populus nigra) biomass by a simultaneous saccharification and fermentation (SSF) process. The composition of liquid and solid fractions obtained after pretreatment, enzymatic digestibility, and ethanol production of poplar biomass pretreated at different experimental conditions was analyzed. The best results were obtained in steam explosion pretreatment at 210 C and 4 min, taking into account cellulose recovery above 95%, enzymatic hydrolysis yield of about 60%, SSF yield of 60% of theoretical, and 41% xylose recovery in the liquid fraction. Large particles can be used for poplar biomass in both pretreatments, since no significant effect of particle size on enzymatic hydrolysis and SSF was obtained.

  13. The characteristic changes of betung bamboo (Dendrocalamus asper pretreated by fungal pretreatment

    Directory of Open Access Journals (Sweden)

    Widya Fatriasari

    2014-05-01

    Full Text Available Normal 0 false false false IN X-NONE X-NONE MicrosoftInternetExplorer4 The fungal pretreatment effect on chemical structural and morphological changes of Betung Bamboo was evaluated based on its biomass components after being cultivated by white rot fungi, Trametes versicolor. Betung bamboo powder (15 g was exposed to liquid inoculum of white rot fungi and incubated at 270C for 15, 30 and 45 days. The treated samples were then characterized by FT-IR spectroscopy, X-Ray diffraction and SEM-EDS analyses. Cultivation for 30 days with 5 and 10% loadings retained greater selectivity compared to that of the other treatments. FTIR spectra demonstrated that the fungus affected the decreasing of functional group quantities without changing the functional groups. The decrease in intensity at wave number of 1246 cm-1 (guaiacyl of lignin was greater than that at wave number of 1328 cm-1 (deformation combination of syringyl and xylan after fungal treatment. X-ray analysis showed the pretreated samples had a higher crystallinity than the untreated ones which might be due to the cleavage of amorphous fractions of cellulose. The pretreated samples have more fragile than the untreated ones confirmed by SEM. Crystalline allomorph calculated by XRD analysis showed that fungus pretreatment for 30 days has transformed triclinic structure of cellulose to monoclinic structure.

  14. Ultrasound and ozone assisted biological degradation of thermally pretreated and anaerobically pretreated distillery wastewater.

    Science.gov (United States)

    Sangave, Preeti C; Gogate, Parag R; Pandit, Aniruddha B

    2007-05-01

    The present work is aimed at increasing the overall efficiency of the treatment process of distillery spent wash using a combination of different treatment techniques. Initially the effluent samples were subjected to Thermal Pretreatment (TPT-DW) and anaerobic treatment (ANA-DW). Advanced oxidation techniques, viz., Ultrasound (US) and Ozone were then used for further COD reduction followed by the conventional aerobic oxidation using mixed microbial consortium. Pretreatment of TPT-DW with US and Ozone (as stand alone techniques) enhanced the subsequent aerobic oxidation rate. For US treated sample, a maximum of 13% COD reduction was attained at the end of 48 h of aerobic oxidation, while for the ozone treated effluent a maximum of 45.6% COD reduction was obtained as compared to mere 1.8% COD reduction for the control (TPT-DW directly subjected to aerobic oxidation) indicating a 25 times increase in the rate of aerobic biodegradation of ozonated sample. Anaerobically treated effluent sample (ANA-DW) could be successfully treated aerobically. In this case, however, the use of advanced oxidation techniques did not result in any synergistic effects. The rate of the aerobic oxidation was slightly higher for the control (ANA-DW directly subjected to aerobic oxidation) as compared to the sample pretreated using ultrasound or ozonation. TOC analysis revealed that between the two pretreatments studied, ozone was found to be superior over US as it led to both COD as well as TOC reduction during the aerobic oxidation step for ANA-DW effluent stream.

  15. FRACTIONAL CRYSTALLIZATION LABORATORY TESTING WITH INTERIM PRETREATMENT SYSTEM FEEDS

    Energy Technology Data Exchange (ETDEWEB)

    HERTING DL

    2008-09-17

    The fractional crystallization process was developed as a pretreatment method for saltcake waste retrieved from Hanford single-shell tanks (SST). The process separates the retrieved SST waste into a high-level waste stream containing the bulk of the radionuclides and a low-activity waste stream containing the bulk of the nonradioactive sodium salts. The Interim Pretreatment System project shifted the focus on pretreatment planning from SST waste to double-shell tank waste.

  16. Enzymic saccharification of pretreated wheat straw.

    Science.gov (United States)

    Vallander, L; Eriksson, K E

    1985-05-01

    Studies of pretreatment of wheat and its subsequent saccharification by Trichoderma reesei cellulases are reported. Steam explosion was found to be the most effective of the pretreatment methods tested. Data are presented describing the effect of enzyme and substrate concentration on the rate and degree of hydrolysis. Significant inhibition of the cellulases was observed when sugar concentrations were 6% or higher. This inhibition increased when glucose and ethanol were present simultaneously. Adsorption of enzymes to the substrate was followed during a 24-h hydrolysis period. An initial rapid and extensive adsorption occurred, followed by a short desorption period that was followed in turn by a further increased adsorption peaking after 3 h. Intermediate removal of hydrolysate, particularly in combination with a second addition of enzyme, clearly improved the yield of saccharification compared to an uninterrupted hydrolysis over a 24-h period. Thus, a 74% yield of reducing sugars was obtained. Furthermore, an increase in the amount of recoverable enzymes was observed under these conditions. Evidence is presented that suggests that a countercurrent technique, whereby free enzymes in recovered hydrolysate are adsorbed onto new substrate, may provide a means of recirculating dissolved enzymes.

  17. Thermal pretreatment of algae for anaerobic digestion.

    Science.gov (United States)

    Marsolek, Michael D; Kendall, Elizabeth; Thompson, Phillip L; Shuman, Teodora Rutar

    2014-01-01

    The objective of this work was to determine the benefit of thermal pretreatment on biogas yield from microalgae-fed anaerobic digester mesocosms. Replicate Nanochloropsis oculata cultures were heated for 4h at 30, 60, and 90°C, as well as at a constant temperature of 90°C for 1, 3.5, and 12h. Net biogas production increased from 0.28L biogas/g volatile solids added (VSa) for the control to 0.39 L biogas/g VSa (p<0.01) when heated at 90°C, but there was no improvement at 30 or 60°C. Increased biogas production correlated with increased soluble chemical oxygen demand (COD). Net biogas production increased as a function of heating time, from 0.32 L biogas/g VSa for the control, to 0.41, 0.43, and 0.44 L biogas/g VSa (p<0.05 for all combinations vs. control) when preheated at 90°C for 1, 3.5, and 12h, respectively. However, despite enhanced biogas production the energy balance is negative for thermal pretreatment.

  18. Nonhazardous Urine Pretreatment Method for Future Exploration Systems Project

    Data.gov (United States)

    National Aeronautics and Space Administration — A nonhazardous urine pretreatment system prototype is proposed that will stabilize urine against biological growth or chemical instabilities without using hazardous...

  19. 40 CFR 417.24 - Pretreatment standards for existing sources.

    Science.gov (United States)

    2010-07-01

    ...) EFFLUENT GUIDELINES AND STANDARDS SOAP AND DETERGENT MANUFACTURING POINT SOURCE CATEGORY Fatty Acid Manufacturing by Fat Splitting Subcategory § 417.24 Pretreatment standards for existing sources. Any...

  20. Feasibility of Hydrothermal Pretreatment on Maize Silage for Bioethanol Production

    DEFF Research Database (Denmark)

    Xu, Jian; Thomsen, Mette Hedegaard; Thomsen, Anne Belinda

    2010-01-01

    The potential of maize silage as a feedstock to produce bioethanol was evaluated in the present study. The hydrothermal pretreatment with five different pretreatment severity factors (PSF) was employed to pretreat the maize silage and compared in terms of sugar recovery, toxic test, and ethanol...... the liquors from the five conditions were not toxic to the Baker’s yeast. Pretreatment under 195°C for 7 min had the similar PSF with that of 185°C for 15 min, and both gave the higher ethanol concentration of 19.92 and 19.98 g/L, respectively. The ethanol concentration from untreated maize silage was only 7...

  1. EFFECT OF SCREW EXTRUSION PRETREATMENT ON PULPS FROM CHEMICAL PULPING

    Directory of Open Access Journals (Sweden)

    Cuihua Dong,

    2012-07-01

    Full Text Available The effect of compressive pretreatment before chemical pulping on the properties of poplar kraft and soda-AQ pulp was evaluated. Compressive pretreatment not only resulted in the dissolution of hemicellulose, but also leached extractives. Pulps made from compressive pretreated wood chips required lower beating energy than the untreated pulps to achieve the same beating degree of 45°SR, and the brightness of the handsheets was improved by 2% ISO. Compressive pretreatment allowed for efficient delignification and saved about 6% alkali consumption to achieve similar pulp screen yield. Furthermore, a higher content of fines and slightly lower mechanical properties were observed after the compressive treatment.

  2. Value added liquid products from waste biomass pyrolysis using pretreatments.

    Science.gov (United States)

    Das, Oisik; Sarmah, Ajit K

    2015-12-15

    Douglas fir wood, a forestry waste, was attempted to be converted into value added products by pretreatments followed by pyrolysis. Four different types of pretreatments were employed, namely, hot water treatment, torrefaction, sulphuric acid and ammonium phosphate doping. Subsequently, pyrolysis was done at 500°C and the resulting bio-oils were analysed for their chemical composition using Karl Fischer titration, thermogravimetry, ion exchange, and gas chromatography. Pretreatment with acid resulted in the highest yield of bio-oil (~60%). The acid and salt pretreatments were responsible for drastic reduction in the lignin oligomers and enhancement of water content in the pyrolytic liquid. The quantity of xylose/mannose reduced as a result of pretreatments. Although, the content of fermentable sugars remained similar across all the pretreatments, the yield of levoglucosan increased. Pretreatment of the biomass with acid yielded the highest amount of levoglucosan in the bio-oil (13.21%). The acid and salt pretreatments also elevated the amount of acetic acid in the bio-oils. Addition of acid and salt to the biomass altered the interaction of cellulose-lignin in the pyrolysis regime. Application of pretreatments should be based on the intended end use of the liquid product having a desired chemical composition.

  3. Nonhazardous Urine Pretreatment Method for Future Exploration Systems Project

    Data.gov (United States)

    National Aeronautics and Space Administration — A novel urine pretreatment that will prevent biological growth or chemical instabilities in urine without using hazardous chemicals is proposed. Untreated urine...

  4. 40 CFR 405.64 - Pretreatment standards for existing sources.

    Science.gov (United States)

    2010-07-01

    ...) EFFLUENT GUIDELINES AND STANDARDS DAIRY PRODUCTS PROCESSING POINT SOURCE CATEGORY Natural and Processed Cheese Subcategory § 405.64 Pretreatment standards for existing sources. Any existing source subject...

  5. Application of high throughput pretreatment and co-hydrolysis system to thermochemical pretreatment. Part 1: dilute acid.

    Science.gov (United States)

    Gao, Xiadi; Kumar, Rajeev; DeMartini, Jaclyn D; Li, Hongjia; Wyman, Charles E

    2013-03-01

    Because conventional approaches for evaluating sugar release from the coupled operations of pretreatment and enzymatic hydrolysis are extremely time and material intensive, high throughput (HT) pretreatment and enzymatic hydrolysis systems have become vital for screening large numbers of lignocellulosic biomass samples to identify feedstocks and/or processing conditions that significantly improve performance and lower costs. Because dilute acid pretreatment offers many important advantages in rendering biomass highly susceptible to subsequent enzymatic hydrolysis, a high throughput pretreatment and co-hydrolysis (HTPH) approach was extended to employ dilute acid as a tool to screen for enhanced performance. First, a single-step neutralization and buffering method was developed to allow effective enzymatic hydrolysis of the whole pretreated slurry. Switchgrass and poplar were then pretreated with 0.5% and 1% acid loadings at a 5% solids concentration, the resulting slurry conditioned with the buffering approach, and the entire mixture enzymatically hydrolyzed. The resulting sugar yields demonstrated that single-step neutralizing and buffering was capable of adjusting the pH as needed for enzymatic saccharification, as well as overcoming enzyme inhibition by compounds released in pretreatment. In addition, the effects of pretreatment conditions and biomass types on susceptibility of pretreated substrates to enzymatic conversion were clearly discernible, demonstrating the method to be a useful extension of HTPH systems.

  6. Understanding of alkaline pretreatment parameters for corn stover enzymatic saccharification

    Directory of Open Access Journals (Sweden)

    Chen Ye

    2013-01-01

    Full Text Available Abstract Background Previous research on alkaline pretreatment has mainly focused on optimization of the process parameters to improve substrate digestibility. To achieve satisfactory sugar yield, extremely high chemical loading and enzyme dosages were typically used. Relatively little attention has been paid to reduction of chemical consumption and process waste management, which has proven to be an indispensable component of the bio-refineries. To indicate alkali strength, both alkali concentration in pretreatment solution (g alkali/g pretreatment liquor or g alkali/L pretreatment liquor and alkali loading based on biomass solids (g alkali/g dry biomass have been widely used. The dual approaches make it difficult to compare the chemical consumption in different process scenarios while evaluating the cost effectiveness of this pretreatment technology. The current work addresses these issues through pretreatment of corn stover at various combinations of pretreatment conditions. Enzymatic hydrolysis with different enzyme blends was subsequently performed to identify the effects of pretreatment parameters on substrate digestibility as well as process operational and capital costs. Results The results showed that sodium hydroxide loading is the most dominant variable for enzymatic digestibility. To reach 70% glucan conversion while avoiding extensive degradation of hemicellulose, approximately 0.08 g NaOH/g corn stover was required. It was also concluded that alkali loading based on total solids (g NaOH/g dry biomass governs the pretreatment efficiency. Supplementing cellulase with accessory enzymes such as α-arabinofuranosidase and β-xylosidase significantly improved the conversion of the hemicellulose by 6–17%. Conclusions The current work presents the impact of alkaline pretreatment parameters on the enzymatic hydrolysis of corn stover as well as the process operational and capital investment costs. The high chemical consumption for alkaline

  7. Estradiol pretreatment attenuated nicotine-induced endothelial cell apoptosis via estradiol functional membrane receptor.

    Science.gov (United States)

    Wang, Li-li; Zhao, Jian-li; Lau, Wayne-Bond; Zhang, Yan-qing; Qiao, Zhong-dong; Wang, Ya-jing

    2011-06-01

    Cigarette smoking is highly associated with increased cardiovascular disease complications. The female population, however, manifests reduced cardiovascular morbidity. We define nicotine's effect upon human umbilical vein endothelial cells (HUVECs), determine whether estradiol might ameliorate endothelial dysfunction via its membrane estrogen receptor (mER), and attempt to elucidate the underlying mechanisms. Endothelial cells were pretreated with estradiol-BSA and measured resultant ion flux across the cells via the patch clamp technique to assess mER is functionality. Estradiol-BSA administration was associated with 30% decreased nicotine-induced apoptosis and also attenuated nicotine-activated phosphorylation of p38 and ERK. Pretreatment of estradiol-BSA triggered a low calcium influx, suggesting ahead low influx calcium played a critical role in the underlying protective mechanisms of estradiol. Furthermore, this estradiol-BSA protection against apoptosis remained effective in the presence of tamoxifen, an intracellular estrogen receptor (iER) inhibitor. Additionally, tamoxifen did not abolish estradiol-BSA's inhibitory effect upon p38 and ERK's activation, giving evidence to the obligatory role of p38 and ERK signaling in the estradiol-BSA's anti-apoptotic action via mER. Our study provides evidence that nicotine enhances endothelial cell apoptosis, but estrogen exerts anti-apoptotic effect through its functional membrane estrogen receptor. Clinically, the nicotine in cigarettes might contribute to endothelial dysfunction, whereas ambient estradiol may provide cellular protection against nicotine-induced injury through its functional membrane receptor via MAPK pathway downregulation.

  8. Negotiating Protection

    DEFF Research Database (Denmark)

    Bille, Mikkel

    strategies are confirming their efficacy, and act as material anchors for negotiating Bedouin identities in response to a rapid transformation from nomadic pastoralists to sedentary wageworkers. The tensions surrounding the materiality of protection, along with the role of the past in the present is further...... strategies are entangled in cultural, religious, and national identities. Using ethnographic methods, I investigate protection against selected risks: harm from evil eyes, violation of domestic sanctity, and cultural heritage dilapidation. Protection against these risks is examined through studies...... investigated through the contested public representations of Ammarin culture, along with a detailed study of the process leading to the protection of Bedouin culture by UNESCO Intangible Cultural Heritage. The overall conclusion of this research is that negotiating efficacious protection against perceived...

  9. Plasma-Assisted Pretreatment of Wheat Straw

    DEFF Research Database (Denmark)

    Schultz-Jensen, Nadja; Leipold, Frank; Bindslev, Henrik;

    2011-01-01

    O3 generated in a plasma at atmospheric pressure and room temperature, fed with dried air (or oxygen-enriched dried air), has been used for the degradation of lignin in wheat straw to optimize the enzymatic hydrolysis and to get more fermentable sugars. A fixed bed reactor was used combined...... straw with desired lignin content because of the online analysis. The O3 consumption of wheat straw and its polymeric components, i.e., cellulose, hemicellulose, and lignin, as well as a mixture of these, dry as well as with 50% water, were studied. Furthermore, the process parameters dry matter content...... and milled particle size (the extent to which the wheat straw was milled) were investigated and optimized. The developed methodology offered the advantage of a simple and relatively fast (0.5–2 h) pretreatment allowing a dry matter concentration of 45–60%. FTIR measurements did not suggest any structural...

  10. Hydrothermal pretreatment of biomass for pellet production

    Energy Technology Data Exchange (ETDEWEB)

    Tooyserkani, Z. [British Columbia Univ., Vancouver, BC (Canada). Clean Energy Research Centre, Biomass and Bioenergy Research Group

    2010-07-01

    This presentation discussed innovative technologies for the production of wood pellets using the hydrothermal pre-treatment of biomass. Conventional techniques use low-cost mill residues, such as saw dust and shavings, as feedstock to produce durable, low-ash pellets. However, mill residues are becoming less available as a result of fewer saw mills, increased pellet production, and increased competition for saw dust. Advanced techniques use mixed biomass such as logging residue as feedstock, creating pellets that are durable for handling and long-term storage, of a higher energy density for transport and mixing with coal for co-firing, and a choice feedstock for biofuels. Advanced pellet production uses steam explosion/pre-treatment in which biomass receives a short-term high-pressure steam treatment followed by sudden decompression. Mild torrefaction seems to have positive feedback, and steam-treated pellets are durable with superior hydrophobicity. 3 figs., 3 tabs.

  11. Chemical characterization and hydrothermal pretreatment of Salicornia bigelovii straw for enhanced enzymatic hydrolysis and bioethanol potential

    DEFF Research Database (Denmark)

    Cybulska, Iwona; Chaturvedi, Tanmay; Brudecki, Grzegorz P.;

    2014-01-01

    Salicornia bigelovii straw was characterized and evaluated as a potential lignocellulosic bioethanol feedstock. S. bigelovii used in the study was grown in the United Arab Emirates using saltwater (40. ppt) for irrigation. Salt removal was performed prior to pretreatment to protect the processing...... equipment and avoid inhibition of enzymes and yeast. Composition of the washed biomass was comparable to traditional lignocellulosic biomasses with relatively high glucan and xylan content (26 and 22. g/100. gDM, respectively) but with lower lignin content (7. g/100. gDM). The washed feedstock was subjected...

  12. Optimization of steam explosion pretreatment. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Foody, P.

    1980-04-01

    Different operating conditions are required to optimize the yield from each of the various fractions in the substrate. Xylose recovery is maximized at short cooking times whereas maximum lignin recovery requires much longer cooking times. Peak glucose yield and rumen digestibility occur at intermediate times. If process conditions are set for maximum glucose yield we have achieved a yield of 68% of the theoretical, based on an average of a dozen substrates tested. Individual results ranged from 46 to 87%. If the process is optimized for maximum total sugars (i.e. glucose plus xylose) we have obtained an average yield of 60%, with a range of 31 to 75%. With rumen microflora, the average value of the in-vitro cellulose digestibility was 82%, with a range of 41 to 90%. The optimum operating conditions for total sugars are a pressure of 500 to 550 psig with a cooking time of 40 to 50 seconds and 35% starting moisture content. Particle size is not a significant factor, nor is pre-steaming or use of a constricting die in the gun nozzle. High quality lignin can be extracted with 80% yield. The Iotech lignin is very soluble, has a low molecular weight and is reactive. The unique properties of the lignin derive from the explosion at the end of the pretreatment. A lignin formaldehyde resin has been successfully formulated and tested. It represents a high value utilization of the lignin byproduct with immediate market potential. A detailed engineering design of the process gives an estimated operating cost of $7.50/OD ton of biomass. At this low cost, the Iotech process achieves many important pretreatment goals in a single step. The substrate has been sterilized; it has been pulverized into a powder; the cellulose has been accessible; and a highly reactive lignin fraction can be recovered and utilized.

  13. Efficacy of pretreatment and treatment against soman intoxication

    NARCIS (Netherlands)

    Philippens, I.H.C.H.M.; Jongsma, M.J.; Vanwersch, R.A.

    2006-01-01

    The efficacy against lethality and post-intoxication incapacitation after 2x LD50 soman of different subacute pretreatment scenarios of 12 days was tested with or without post-intoxication therapy in guinea pigs. These pretreatment regimes were 1) the currently used pyridostigmine (PYR, 0.04 mg/kg/h

  14. 40 CFR 417.14 - Pretreatment standards for existing sources.

    Science.gov (United States)

    2010-07-01

    ...) EFFLUENT GUIDELINES AND STANDARDS SOAP AND DETERGENT MANUFACTURING POINT SOURCE CATEGORY Soap Manufacturing... works must comply with 40 CFR part 403. In addition, the following pretreatment standard establishes the.... Pollutant or pollutant property Pretreatment standard pH No limitation. BOD5 Do. TSS Do. Oil and grease...

  15. 40 CFR 417.34 - Pretreatment standards for existing sources.

    Science.gov (United States)

    2010-07-01

    ...) EFFLUENT GUIDELINES AND STANDARDS SOAP AND DETERGENT MANUFACTURING POINT SOURCE CATEGORY Soap Manufacturing... treatment works must comply with 40 CFR part 403. In addition, the following pretreatment standard... subpart. Pollutant or pollutant property Pretreatment standard pH No limitation. BOD5 Do. TSS Do. Oil...

  16. Optimization of the dilute maleic acid pretreatment of wheat straw

    NARCIS (Netherlands)

    Kootstra, A.M.J.; Beeftink, H.H.; Scott, E.L.; Sanders, J.P.M.

    2009-01-01

    Background - In this study, the dilute maleic acid pretreatment of wheat straw is optimized, using pretreatment time, temperature and maleic acid concentration as design variables. A central composite design was applied to the experimental set up. The response factors used in this study are: (1) glu

  17. Structural changes of corn stover lignin during acid pretreatment.

    Science.gov (United States)

    Moxley, Geoffrey; Gaspar, Armindo Ribeiro; Higgins, Don; Xu, Hui

    2012-09-01

    In this study, raw corn stover was subjected to dilute acid pretreatments over a range of severities under conditions similar to those identified by the National Renewable Energy Laboratory (NREL) in their techno-economic analysis of biochemical conversion of corn stover to ethanol. The pretreated corn stover then underwent enzymatic hydrolysis with yields above 70 % at moderate enzyme loading conditions. The enzyme exhausted lignin residues were characterized by ³¹P NMR spectroscopy and functional moieties quantified and correlated to enzymatic hydrolysis yields. Results from this study indicated that both xylan solubilization and lignin degradation are important for improving the enzyme accessibility and digestibility of dilute acid pretreated corn stover. At lower pretreatment temperatures, there is a good correlation between xylan solubilization and cellulose accessibility. At higher pretreatment temperatures, lignin degradation correlated better with cellulose accessibility, represented by the increase in phenolic groups. During acid pretreatment, the ratio of syringyl/guaiacyl functional groups also gradually changed from less than 1 to greater than 1 with the increase in pretreatment temperature. This implies that more syringyl units are released from lignin depolymerization of aryl ether linkages than guaiacyl units. The condensed phenolic units are also correlated with the increase in pretreatment temperature up to 180 °C, beyond which point condensation reactions may overtake the hydrolysis of aryl ether linkages as the dominant reactions of lignin, thus leading to decreased cellulose accessibility.

  18. Wet explosion pretreatment of sugarcane bagasse for enhanced enzymatic hydrolysis

    DEFF Research Database (Denmark)

    Biswas, Rajib; Uellendahl, Hinrich; Ahring, Birgitte Kiær

    2014-01-01

    Wet explosion pretreatment of sugarcane bagasse was investigated in pilot-scale with the aim of obtaining the highest possible sugar yield after pretreatment. The temperatures used were 155, 170, 185 and 200 C with or without addition of oxygen (0.6 MPa pressure). Enzymatic hydrolysis of washed...

  19. Vitamin C Pretreatment Enhances the Antibacterial Effect of Cold Atmospheric Plasma

    Science.gov (United States)

    Helgadóttir, Saga; Pandit, Santosh; Mokkapati, Venkata R. S. S.; Westerlund, Fredrik; Apell, Peter; Mijakovic, Ivan

    2017-01-01

    Bacterial biofilms are three-dimensional structures containing bacterial cells enveloped in a protective polymeric matrix, which renders them highly resistant to antibiotics and the human immune system. Therefore, the capacity to make biofilms is considered as a major virulence factor for pathogenic bacteria. Cold Atmospheric Plasma (CAP) is known to be quite efficient in eradicating planktonic bacteria, but its effectiveness against biofilms has not been thoroughly investigated. The goal of this study was to evaluate the effect of exposure of CAP against mature biofilm for different time intervals and to evaluate the effect of combined treatment with vitamin C. We demonstrate that CAP is not very effective against 48 h mature bacterial biofilms of several common opportunistic pathogens: Staphylococcus epidermidis, Escherichia coli, and Pseudomonas aeruginosa. However, if bacterial biofilms are pre-treated with vitamin C for 15 min before exposure to CAP, a significantly stronger bactericidal effect can be obtained. Vitamin C pretreatment enhances the bactericidal effect of cold plasma by reducing the viability from 10 to 2% in E. coli biofilm, 50 to 11% in P. aeruginosa, and 61 to 18% in S. epidermidis biofilm. Since it is not feasible to use extended CAP treatments in medical practice, we argue that the pre-treatment of infectious lesions with vitamin C prior to CAP exposure can be a viable route for efficient eradication of bacterial biofilms in many different applications. PMID:28275584

  20. Laboratory Tests on Post-Filtration Precipitation in the WTP Pretreatment Process

    Energy Technology Data Exchange (ETDEWEB)

    Russell, Renee L.; Peterson, Reid A.; Rinehart, Donald E.; Crum, Jarrod V.

    2009-11-20

    Pacific Northwest National Laboratory (PNNL) has been tasked by Bechtel National Inc. (BNI) on the River Protection Project-Hanford Tank Waste Treatment and Immobilization Plant (RPP-WTP) project to perform research and development activities to resolve technical issues identified for the Pretreatment Facility (PTF). The Pretreatment Engineering Platform (PEP) was designed, constructed, and operated as part of a plan to respond to issue M12, "Undemonstrated Leaching Processes," of the External Flowsheet Review Team (EFRT) issue response plan (Barnes et al. 2006). The PEP is a 1/4.5-scale test platform designed to simulate the WTP pretreatment caustic leaching, oxidative leaching, ultrafiltration solids concentration, and slurry washing processes. The PEP replicates the WTP leaching processes using prototypic equipment and control strategies. A simplified flow diagram of the PEP system is shown in Figure 1.1. Two operating scenarios are currently being evaluated for the ultrafiltration process (UFP) and leaching operations. The first scenario has caustic leaching performed in the UFP-2 ultrafiltration feed vessels (i.e., vessel UFP-VSL-T02A in the PEP; and vessels UFP-VSL-00002A and B in the WTP PTF). The second scenario has caustic leaching conducted in the UFP-1 ultrafiltration feed preparation vessels (i.e., vessels UFP-VSL-T01A and B in the PEP; vessels UFP-VSL-00001A and B in the WTP PTF).

  1. U-74389G PRETREATMENT ATTENUATING WARM ISCHEMIA INJURY IN LIVER TRANSPLANTATION

    Institute of Scientific and Technical Information of China (English)

    严佶祺; 李宏为; 张明钧; 杨卫平; 蔡伟耀; 林言箴

    2002-01-01

    Objective To investigate the protective role of lazaroid U-74389G pretreatment against warm ischemia injury of rat liver transplantation from non-heart-beating donors. Methods Rat othortopic liver transplantation was perfomed in 4 groups (N-45, N-60 , pN-45 and pN-60 ), according to pretreatrnent with U-74389G or not, and the non-heart-beating time 45min or 60min before donor liver harvested. Survival rates, liver functions, MDA values and graft pathology of each group were compared. Results The oneweek survival rates ofGroupN-45, N-60 , pN-45 and pN-60 were25% (2/8), 0% (0/8), 58.3% (7/12)and 33.3% ( 4/12 ), respectively. U-74389G pretreatment significantly increased survival rate of rat liver transplantation from non-heart-beating donors, but also improved liver functions atd graft pathologies, as well as decreased MDA expression. Conclusion U-74389G pretreatment could attenuate warm ischemia reperfusion injury of rat liver transplantation from non-heart-beating donors.

  2. Ensiling as pretreatment of grass for lignocellulosic biomass conversion

    DEFF Research Database (Denmark)

    Ambye-Jensen, Morten

    for subsequent enzymatic saccharification of cellulose and hemicellulose, by using the temperate grass Festulolium Hykor. The method was additionally combined with hydrothermal treatment, in order to decrease the required severity of an industrial applied pretreatment method. The first part of the project......Development of sound technologies of biomass conversion will be increasingly important for many years to come as planetary bounderies drive the development towards a biobased society. Pretreatment of lignocellulosic biomass is, in this regard, an essential technology. Current pretreatment methods......, based on severe physio-chemical processes, are effective, however, they are also costly and energy demanding. An alternative biological pretreatment method, based on the well-known biomass preservation of ensiling, has been proposed. Ensiling holds potential as an integrated storage and pretreatment...

  3. Dielectric barrier discharge plasma pretreatment on hydrolysis of microcrystalline cellulose

    Science.gov (United States)

    Fangmin, HUANG; Zhouyang, LONG; Sa, LIU; Zhenglong, Qin

    2017-04-01

    Dielectric barrier discharge (DBD) plasma was used as a pretreatment method for downstream hydrolysis of microcrystalline cellulose (MCC). The degree of polymerization (DP) of MCC decreased after it was pretreated by DBD plasma under a carrier gas of air/argon. The effectiveness of depolymerization was found to be influenced by the crystallinity of MCC when under the pretreatment of DBD plasma. With the addition of tert-butyl alcohol in the treated MCC water suspension solution, depolymerization effectiveness of MCC was inhibited. When MCC was pretreated by DBD plasma for 30 min, the total reducing sugar concentration (TRSC) and liquefaction yield (LY) of pretreated-MCC (PMCC) increased by 82.98% and 34.18% respectively compared with those for raw MCC.

  4. Pretreatment with TCDD exacerbates liver injury from Concanavalin A: critical role for NK cells.

    Science.gov (United States)

    Fullerton, Aaron M; Roth, Robert A; Ganey, Patricia E

    2013-11-01

    For many liver diseases, including viral and autoimmune hepatitis, immune cells play an important role in the development and progression of liver injury. Concanavalin A (Con A) administration to rodents has been used as a model of immune-mediated liver injury resembling human autoimmune hepatitis. 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) has been demonstrated to alter the development of immune-mediated diseases. Mice pretreated with TCDD developed exacerbated liver injury in response to administration of a mild dose (6 mg/kg) of Con A. In the present study, we tested the hypothesis that TCDD pretreatment exacerbates Con A-induced liver injury by enhancing the activation and recruitment of accessory cell types including neutrophils, macrophages, and natural killer (NK) cells. Mice were treated with 0, 0.3, 3, or 30 μg/kg TCDD and 4 days later with Con A or saline. TCDD pretreatment with doses of 3 and 30 μg/kg significantly increased liver injury from Con A administration. The plasma concentrations of neutrophil chemokines were significantly increased in TCDD-pretreated mice after Con A administration. NKT cell-deficient (CD1d KO) mice were used to examine whether NKT cells were required for TCDD/Con A-induced liver injury. CD1d KO mice were completely protected from liver injury induced by treatment with Con A alone, whereas the injury from TCDD/Con A treatment was reduced but not eliminated. However, T-cell deficient (RAG1 KO) mice were protected from liver injury induced by Con A irrespective of pretreatment with TCDD. TCDD/Con A treatment increased the percentage of NK cells expressing the activation marker CD69. Depletion of NK cells prior to treatment resulted in significant reductions in plasma interferon-γ and liver injury from TCDD/Con A treatment. In summary, exposure to TCDD exacerbated the immune-mediated liver injury induced by Con A, and our findings suggest that NK cells play a critical role in this response.

  5. Enhanced thermophilic fermentative hydrogen production from cassava stillage by chemical pretreatments

    DEFF Research Database (Denmark)

    Wang, Wen; Luo, Gang; Xie, Li;

    2013-01-01

    Acid and alkaline pretreatments for enhanced hydrogen production from cassava stillage were investigated in the present study. The result showed that acid pretreatment was suitable for enhancement of soluble carbohydrate while alkaline pretreatment stimulated more soluble total organic carbon pro...

  6. Tailoring Wet Explosion Process Parameters for the Pretreatment of Cocksfoot Grass for High Sugar Yields

    DEFF Research Database (Denmark)

    Njoku, Stephen Ikechukwu; Ahring, Birgitte Kiær; Uellendahl, Hinrich

    2013-01-01

    The pretreatment of lignocellulosic biomass is crucial for efficient subsequent enzymatic hydrolysis and ethanol fermentation. In this study, wet explosion (WEx) pretreatment was applied to cocksfoot grass and pretreatment conditions were tailored for maximizing the sugar yields using response...

  7. Wet air oxidation pretreatment of biomethanated distillery effluent: mapping pretreatment efficiency in terms color, toxicity reduction and biogas generation.

    Science.gov (United States)

    Sarat Chandra, T; Malik, S N; Suvidha, G; Padmere, M L; Shanmugam, P; Mudliar, S N

    2014-04-01

    The effluents from molasses-based distilleries after biomethanation are beset with problems of intensified dark brown color, high residual COD, low biodegradability index (BOD/COD ratio Wet air oxidation (WAO) pretreatment of biomethanated distillery effluent resulted in substantial enhancement in the biodegradability index (BI) (up to 0.8). WAO pretreated effluent on anaerobic digestion indicated favorable biogas generation with methane content up to 64% along with concomitant COD reduction up to 54.75%. The HPLC analysis indicated that the pretreatment facilitated degradation of major color containing compounds-namely melanoidins, up to 97.8%. The pretreated effluent with enhanced biodegradability along with substantially reduced color also indicated positive effect on seed germination (up to 100%), implying toxicity reduction of the effluent post WAO pretreatment.

  8. Memory protection

    Science.gov (United States)

    Denning, Peter J.

    1988-01-01

    Accidental overwriting of files or of memory regions belonging to other programs, browsing of personal files by superusers, Trojan horses, and viruses are examples of breakdowns in workstations and personal computers that would be significantly reduced by memory protection. Memory protection is the capability of an operating system and supporting hardware to delimit segments of memory, to control whether segments can be read from or written into, and to confine accesses of a program to its segments alone. The absence of memory protection in many operating systems today is the result of a bias toward a narrow definition of performance as maximum instruction-execution rate. A broader definition, including the time to get the job done, makes clear that cost of recovery from memory interference errors reduces expected performance. The mechanisms of memory protection are well understood, powerful, efficient, and elegant. They add to performance in the broad sense without reducing instruction execution rate.

  9. Protected Areas

    Data.gov (United States)

    Kansas Data Access and Support Center — This dataset shows the boundaries of properties in Kansas in public or institutional ownership that contain ecological resources that merit some level of protection....

  10. Ammonia Pretreatment of Corn Stover Enables Facile Lignin Extraction

    Energy Technology Data Exchange (ETDEWEB)

    Mittal, Ashutosh; Katahira, Rui; Donohoe, Bryon S.; Pattathil, Sivakumar; Kandemkavil, Sindhu; Reed, Michelle L.; Biddy, Mary J.; Beckham, Gregg T.

    2017-01-30

    Thermochemical pretreatment of lignocellulose is often employed to render polysaccharides more digestible by carbohydrate-active enzymes to maximize sugar yields. The fate of lignin during pretreatment, however, is highly dependent on the chemistry employed and must be considered in cases where lignin valorization is targeted alongside sugar conversion - an important feature of future biorefinery development. Here, a two-step process is demonstrated in which anhydrous ammonia (AA) pretreatment is followed by mild NaOH extraction on corn stover to solubilize and fractionate lignin. As known, AA pretreatment simultaneously alters the structure of cellulose with enhanced digestibility while redistributing lignin. The AA-pretreated residue is then extracted with dilute NaOH at mild conditions to maximize lignin separation, resulting in a digestible carbohydrate-rich solid fraction and a solubilized lignin stream. Lignin removal of more than 65% with over 84% carbohydrate retention is achieved after mild NaOH extraction of AA-pretreated corn stover with 0.1 M NaOH at 25 degrees C. Two-dimensional nuclear magnetic resonance (2D-NMR) spectroscopy of the AA-pretreated residue shows that ammonolysis of ester bonds occurs to partially liberate hydroxycinnamic acids, and the AA-pretreated/NaOH-extracted residue exhibits a global reduction of all lignin moieties caused by reduced lignin content. A significant reduction (~70%) in the weight-average molecular weight (Mw) of extracted lignin is also achieved. Imaging of AA-pretreated/NaOH extracted residues show extensive delamination and disappearance of coalesced lignin globules from within the secondary cell walls. Glycome profiling analyses demonstrates ultrastructural level cell wall modifications induced by AA pretreatment and NaOH extraction, resulting in enhanced extractability of hemicellulosic glycans, indicating enhanced polysaccharide accessibility. The glucose and xylose yields from enzymatic hydrolysis of AA-pretreated

  11. Corrosion protection

    Science.gov (United States)

    Brown, Donald W.; Wagh, Arun S.

    2003-05-27

    There has been invented a chemically bonded phosphate corrosion protection material and process for application of the corrosion protection material for corrosion prevention. A slurry of iron oxide and phosphoric acid is used to contact a warm surface of iron, steel or other metal to be treated. In the presence of ferrous ions from the iron, steel or other metal, the slurry reacts to form iron phosphates which form grains chemically bonded onto the surface of the steel.

  12. Radiation Protection

    Energy Technology Data Exchange (ETDEWEB)

    Loos, M

    2001-04-01

    Major achievements of SCK-CEN's Radiation Protection Department in 2000 are described. The main areas for R and D of the department remain neutron dosimetry and neutron activation analysis, safeguards information handling and non-destructive assay techniques. Further activities include low-level radioactivity measurements in environmental and biological samples and radiation protection research. Finally, achievements in decision strategy research and social sciences in nuclear research are reported.

  13. A comparison of the efficacy of pyridostigmine alone and the combination of pyridostigmine with anticholinergic drugs as pharmacological pretreatment of tabun-poisoned rats and mice.

    Science.gov (United States)

    Kassa, Jirí; Vachek, J

    2002-08-15

    The ability of two types of pharmacological pretreatment (pyridostigmine alone or pyridostigmine in combination with two anticholinergic drugs) to increase the resistance of rats and mice against tabun and to increase the therapeutic efficacy of common antidotal treatment of tabun-poisoned rats and mice was compared. A significant decrease in the LD50 values of tabun was observed when mice as well as rats were pretreated with the prophylactic antidotal mixture consisting of pyridostigmine, benactyzine and trihexyphenidyle, designated PANPAL. Pyridostigmine-pretreated rats were also more resistant against acute lethal effects of tabun but pyridostigmine-induced resistance of rats was not so high as PANPAL-induced resistance. In addition, the pharmacological pretreatment with pyridostigmine alone was not able to protect mice against tabun-induced acute toxicity. The pharmacological pretreatment with pyridostigmine alone was able to increase the efficacy of currently used antidotal treatment (obidoxime in combination with atropine and diazepam) of tabun-induced poisoning, but PANPAL-induced increase in the efficacy of the same antidotal treatment was significantly higher than an increase induced by pyridostigmine alone. PANPAL-induced increase in the efficacy of antidotal treatment of tabun poisoning was also observed in mice. These findings confirm that PANPAL pretreatment of tabun-poisoned rats and mice seems to be much more suitable than currently used pyridostigmine alone.

  14. 40 CFR 439.37 - Pretreatment standards for new sources (PSNS).

    Science.gov (United States)

    2010-07-01

    ...) EFFLUENT GUIDELINES AND STANDARDS PHARMACEUTICAL MANUFACTURING POINT SOURCE CATEGORY Chemical Synthesis... achieve the pretreatment standard for ammonia (as N). (b) The pretreatment standards for cyanide are...

  15. Novel pretreatment of steam explosion associated with ammonium chloride preimpregnation.

    Science.gov (United States)

    Chen, Hongzhang; Li, Guanhua; Li, Hongqiang

    2014-02-01

    Improving nitrogen content and enhancing enzymatic hydrolysis are key processes involved in cellulosic ethanol production. Steam explosion (SE) associated with NH4Cl preimpregnation was carried out to investigate effects of the pretreatment on nitrogen content, enzymatic digestibility, and ethanol production. Results showed that nitrogen content in pretreated samples increased, which can be used as nitrogen resource for ethanol fermentation. The highest glucose yield of sample pretreated by 1.4MPa SE with 90g/l NH4Cl preimpregnation was 62.64%, which was 2.1 and 0.2 times higher than that of untreated sample and 1.4MPa SE pretreated sample, respectively. Ethanol yield of sample pretreated by 1.1MPa SE with 135g/l NH4Cl preimpregnation resulted in 1.93 and 0.69 times higher than that of untreated sample and 1.1MPa SE pretreated sample, respectively. This novel pretreatment improved nitrogen content and enhanced enzymatic digestibility under mild conditions, and could be recommended to further industrial application.

  16. Breakdown of hierarchical architecture in cellulose during dilute acid pretreatments

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Yan [Northeastern Univ., Boston, MA (United States); Inouye, Hideyo [Northeastern Univ., Boston, MA (United States); Yang, Lin [Brookhaven National Lab. (BNL), Upton, NY (United States); Himmel, Michael E. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Tucker, Melvin [National Renewable Energy Lab. (NREL), Golden, CO (United States); Makowski, Lee [Northeastern Univ., Boston, MA (United States)

    2015-02-28

    Cellulose can work as a feedstock for sustainable bioenergy because of its global abundance. Pretreatment of biomass has significant influence on the chemical availability of cellulose locked in recalcitrant microfibrils. Optimizing pretreatment depends on an understanding of its impact on the microscale and nanoscale molecular architecture. X-ray scattering experiments have been performed on native and pre-treated maize stover and models of cellulose architecture have been derived from these data. Ultra small-angle, very small-angle and small-angle X-ray scattering (USAXS, VSAXS and SAXS) probe three different levels of architectural scale. USAXS and SAXS have been used to study cellulose at two distinct length scales, modeling the fibrils as ~30 Å diameter rods packed into ~0.14 μm diameter bundles. VSAXS is sensitive to structural features at length scales between these two extremes. Detailed analysis of diffraction patterns from untreated and pretreated maize using cylindrical Guinier plots and the derivatives of these plots reveals the presence of substructures within the ~0.14 μm diameter bundles that correspond to grouping of cellulose approximately 30 nm in diameter. These sub-structures are resilient to dilute acid pretreatments but are sensitive to pretreatment when iron sulfate is added. Our results provide evidence of the hierarchical arrangement of cellulose at three length scales and the evolution of these arrangements during pre-treatments.

  17. Effects of Pretreatment Methods on Electrodes and SOFC Performance

    Directory of Open Access Journals (Sweden)

    Guo-Bin Jung

    2014-06-01

    Full Text Available Commercially available tapes (anode, electrolyte and paste (cathode were choosen to prepare anode-supported cells for solid oxide fuel cell applications. For both anode-supported cells or electrolyte-supported cells, the anode needs pretreatment to reduce NiO/YSZ to Ni/YSZ to increase its conductivity as well as its catalytic characteristics. In this study, the effects of different pretreatments (open-circuit, closed-circuit on cathode and anodes as well as SOFC performance are investigated. To investigate the influence of closed-circuit pretreatment on the NiO/YSZ anode alone, a Pt cathode is utilized as reference for comparison with the LSM cathode. The characterization of the electrical resistance, AC impedance, and SOFC performance of the resulting electrodes and/or anode-supported cell were carried out. It’s found that the influence of open-circuit pretreatment on the LSM cathode is limited. However, the influence of closed-circuit pretreatment on both the LSM cathode and NiO/YSZ anode and the resulting SOFC performance is profound. The effect of closed-circuit pretreatment on the NiO/YSZ anode is attributed to its change of electronic/pore structure as well as catalytic characteristics. With closed-circuit pretreatment, the SOFC performance improved greatly from the change of LSM cathode (and Pt reference compared to the Ni/YSZ anode.

  18. Lime pretreatment and fermentation of enzymatically hydrolyzed sugarcane bagasse.

    Science.gov (United States)

    Rabelo, Sarita C; Maciel Filho, Rubens; Costa, Aline C

    2013-03-01

    Sugarcane bagasse was subjected to lime (calcium hydroxide) pretreatment and enzymatic hydrolysis for second-generation ethanol production. A central composite factorial design was performed to determine the best combination of pretreatment time, temperature, and lime loading, as well as to evaluate the influence of enzymatic loadings on hydrolysis conversion. The influence of increasing solids loading in the pretreatment and enzymatic hydrolysis stages was also determined. The hydrolysate was fermented using Saccharomyces cerevisiae in batch and continuous mode. In the continuous fermentation, the hydrolysates were concentrated with molasses. Lime pretreatment significantly increased the enzymatic digestibility of sugarcane bagasse without the need for prior particle size reduction. In the optimal pretreatment conditions (90 h, 90 °C, 0.47 glime/g bagasse) and industrially realistic conditions of hydrolysis (12.7 FPU/g of cellulase and 7.3 CBU/g of β-glucosidase), 139.6 kglignin/ton raw bagasse and 126.0 kg hemicellulose in the pretreatment liquor per ton raw bagasse were obtained. The hydrolysate from lime pretreated sugarcane bagasse presented low amounts of inhibitors, leading to ethanol yield of 164.1 kgethanol/ton raw bagasse.

  19. Enhanced enzymatic conversion with freeze pretreatment of rice straw

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Ken-Lin; Thitikorn-amorn, Jitladda; Ou, Bay-Ming; Chen, Shan-He; Huang, Po-Jung [Institute of Biological Chemistry and Genomics Research Center Academia Sinica, Nankang, Taipei 115 (China); Hsieh, Jung-Feng [Department of Food Science, Fu Jen Catholic University, Xin Zhuang, Taipei 242 (China); Ratanakhanokchai, Khanok [School of Bioresources and Technology, King Mongkut' s University of Technology Thonburi, Bangkok 10150 (Thailand); Chen, Shui-Tein [Institute of Biological Chemistry and Genomics Research Center Academia Sinica, Nankang, Taipei 115 (China); Institute of Biochemical Sciences, College of Life Science, National Taiwan University, Taipei 106 (China)

    2011-01-15

    Production of bioethanol by the conversion of lignocellulosic waste has attracted much interest in recent years, because of its low cost and great potential availability. The pretreatment process is important for increasing the enzymatic digestibility of lignocellulosic materials. Enzymatic conversion with freeze pretreatment of rice straw was evaluated in this study. The freeze pretreatment was found to significantly increase the enzyme digestibility of rice straw from 48% to 84%. According to the results, enzymatic hydrolysis of unpretreated rice straw with 150 U cellulase and 100 U xylanase for 48 h yielded 226.77 g kg{sup -1} and 93.84 g kg{sup -1} substrate-reducing sugars respectively. However, the reducing sugar yields from freeze pretreatment under the same conditions were 417.27 g kg{sup -1} and 138.77 g kg{sup -1} substrate, respectively. In addition, hydrolyzates analysis showed that the highest glucose yield obtained during the enzymatic hydrolysis step in the present study was 371.91 g kg{sup -1} of dry rice straw, following pretreatment. Therefore, the enhanced enzymatic conversion with freeze pretreatment of rice straw was observed in this study. This indicated that freeze pretreatment was highly effective for enzymatic hydrolysis and low environmental impact. (author)

  20. Investigation of Pleurotus ostreatus pretreatment on switchgrass for ethanol production

    Science.gov (United States)

    Slavens, Shelyn Gehle

    Fungal pretreatment using the white-rot fungus Pleurotus ostreatus on switchgrass for ethanol production was studied. In a small-scale storage study, small switchgrass bales were inoculated with fungal spawn and automatically watered to maintain moisture. Sampled at 25, 53, and 81 d, the switchgrass composition was determined and liquid hot water (LHW) pretreatment was conducted. Fungal pretreatment significantly decreased the xylan and lignin content; glucan was not significantly affected by fungal loading. The glucan, xylan, and lignin contents significantly decreased with increased fungal pretreatment time. The effects of the fungal pretreatment were not highly evident after the LHW pretreatment, showing only changes based on sampling time. Although other biological activity within the bales increased cellulose degradation, the fungal pretreatment successfully reduced the switchgrass lignin and hemicellulose contents. In a laboratory-scale nutrient supplementation study, copper, manganese, glucose, or water was added to switchgrass to induce production of ligninolytic enzymes by P. ostreatus. After 40 d, ligninolytic enzyme activities and biomass composition were determined and simultaneous saccharification and fermentation (SSF) was conducted to determine ethanol yield. Laccase activity was similar for all supplements and manganese peroxidase (MnP) activity was significantly less in copper-treated samples than in the other fungal-inoculated samples. The fungal pretreatment reduced glucan, xylan, and lignin content, while increasing extractable sugars content. The lowest lignin contents occurred in the water-fungal treated samples and produced the greatest ethanol yields. The greatest lignin contents occurred in the copper-fungal treated samples and produced the lowest ethanol yields. Manganese-fungal and glucose-fungal treated samples had similar, intermediate lignin contents and produced similar, intermediate ethanol yields. Ethanol yields from switchgrass

  1. Protected Areas - Protected Federal Lands

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — The Federal Lands data consists of land areas that are run and maintained by U.S. Governmental authorities and are considered protected.The Department of Natural...

  2. Evaluation of High Solids Alkaline Pretreatment of Rice Straw

    OpenAIRE

    Cheng, Yu-Shen; Zheng, Yi; Yu, Chao Wei; Dooley, Todd M.; Jenkins, Bryan M.; VanderGheynst, Jean S.

    2010-01-01

    Fresh-harvested, air-dried rice straw was pretreated at a water content of 5 g H2O/g straw using sodium hydroxide (NaOH) and compared to pretreatment at 10 g H2O/g straw by hydrated lime (Ca(OH)2). Full factorial experiments including parallel wash-only treatments were completed with both sources of alkali. The experiments were designed to measure the effects of alkaline loading and pretreatment time on delignification and sugar yield upon enzymatic hydrolysis. Reaction temperature was held c...

  3. Optimization of microwave pretreatment on wheat straw for ethanol production

    DEFF Research Database (Denmark)

    Xu, Jian; Chen, Hongzhang; Kádár, Zsófia;

    2011-01-01

    An orthogonal design (L9(34)) was used to optimize the microwave pretreatment on wheat straw for ethanol production. The orthogonal analysis was done based on the results obtained from the nine pretreatments. The effect of four factors including the ratio of biomass to NaOH solution, pretreatment......, the NaOH concentration of 10 kg m−3, the microwave power of 1000 W for 15 min was confirmed to be the optimal condition. The ethanol yield was 148.93 g kg−1 wheat straw at this condition, much higher than that from the untreated material which was only 26.78 g kg−1....

  4. Evaluation of wet oxidation pretreatment for enzymatic hydrolysis of softwood

    DEFF Research Database (Denmark)

    Palonen, H.; Thomsen, A.B.; Tenkanen, M.;

    2004-01-01

    The wet oxidation pretreatment (water, oxygen, elevated temperature, and pressure) of softwood (Picea abies) was investigated for enhancing enzymatic hydrolysis. The pretreatment was preliminarily optimized. Six different combinations of reaction time, temperature, and pH were applied......, and the compositions of solid and liquid fractions were analyzed. The solid fraction after wet oxidation contained 58-64% cellulose, 2-16% hemicellulose, and 24-30% lignin. The pretreatment series gave information about the roles of lignin and hemicellulose in the enzymatic hydrolysis. The temperature...

  5. Resveratrol Pretreatment Ameliorates TNBS Colitis in Rats.

    Science.gov (United States)

    Yildiz, Gulserap; Yildiz, Yuksel; Ulutas, Pinar A; Yaylali, Asl; Ural, Muruvvet

    2015-01-01

    Inflammatory bowel disease (IBD) is a chronic intestinal inflammatory disease in humans constituting a major health concern today whose prevalence has been increasing over the world. Production of reactive oxygen species (ROS) and disturbed capacity of antioxidant defense in IBD subjects have been reported. Antioxidants may play a significant role in IBD treatment. This study aimed at evaluating ameliorative effects of intraperitoneal resveratrol pretreatment on trinitrobenzene sulphonic acid (TNBS)-induced colitis in rats. Thirty five Wistar-Albino female rats were divided equally into five groups. Inflammation was induced by the intrarectal administration of TNBS under anesthesia. Intraperitoneal administration of resveratrol (RSV) at a concentration of 10mg/kg/day for 5 days before the induction of colitis significantly reduced microscopy score and malondialdehyde (MDA) levels and increased glutathione peroxidase (GSH Px) activity compared to TNBS and vehicle groups. Also an insignificant increase in catalase (CAT) activity was observed in the RSV treated group compared to TNBS and vehicle groups. In this paper, the most recent patent on the identification and treatment of IBD was indicated. In conclusion, antioxidant RSV proved to have a beneficial effect on TNBS colitis in rats. In light of these advantageous results, the RSV can be considered as adjuvant agent in IBD treatments.

  6. Donor pretreatment with carbon monoxide prevents ischemia/reperfusion injury following heart transplantation in rats

    Directory of Open Access Journals (Sweden)

    Noritomo Fujisaki

    2016-01-01

    Full Text Available Because inhaled carbon monoxide (CO provides potent anti-inflammatory and antioxidant effects against ischemia reperfusion injury, we hypothesized that treatment of organ donors with inhaled CO would decrease graft injury after heart transplantation. Hearts were heterotopically transplanted into syngeneic Lewis rats after 8 hours of cold preservation in University of Wisconsin solution. Donor rats were exposed to CO at a concentration of 250 parts per million for 24 hours via a gas-exposure chamber. Severity of myocardial injury was determined by total serum creatine phosphokinase and troponin I levels at three hours after reperfusion. In addition, Affymetrix gene array analysis of mRNA transcripts was performed on the heart graft tissue prior to implantation. Recipients of grafts from CO-exposed donors had lower levels of serum troponin I and creatine phosphokinase; less upregulation of mRNA for interleukin-6, intercellular adhesion molecule-1, and tumor necrosis factor-α; and fewer infiltrating cells. Although donor pretreatment with CO altered the expression of 49 genes expressly represented on the array, we could not obtain meaningful data to explain the mechanisms by which CO potentiated the protective effects.Pretreatment with CO gas before organ procurement effectively protected cardiac grafts from ischemia reperfusion-induced injury in a rat heterotopic cardiac transplant model. A clinical report review indicated that CO-poisoned organ donors may be comparable to non-poisoned donors.

  7. Loxoribine pretreatment reduces Salmonella Enteritidis organ invasion in 1-day-old chickens.

    Science.gov (United States)

    Swaggerty, C L; He, H; Genovese, K J; Duke, S E; Kogut, M H

    2012-04-01

    Young poultry exhibit a transient colonization by some food-borne pathogens, including Salmonella, during the first week of life that stems from immature innate and acquired defense mechanisms. Consequently, modulation of the hosts' natural immune response is emerging as an important area of interest for food animal producers, including the poultry industry. Toll-like receptor (TLR) agonists have been shown to boost the innate immune response in young chickens and increase their resistance to colonization by Salmonella enterica serovar Enteritidis. The objective of the present study was to determine if pretreatment with loxoribine, a TLR7 agonist and immune modulator, protects young chicks from Salmonella Enteritidis organ invasion. Loxoribine (0-100 μg) was administered intra-abdominally to 1-d-old broiler chicks, and 4 h later, the birds were challenged orally with Salmonella Enteritidis. Twenty-four hours postchallenge, birds were euthanized and the liver and spleen aseptically removed and cultured for Salmonella Enteritidis. This was carried out on 3 separate occasions using 26 to 50 chicks per dose per experiment. Pretreatment of chicks with loxoribine (6.25-25 μg) significantly (P ≤ 0.05) reduced liver and spleen organ invasion by Salmonella Enteritidis. Higher doses (50-100 μg) of loxoribine had no effect. The results obtained in this study indicate that there is a potential application for using loxoribine to increase protection of young chicks when they are most susceptible to infections with Salmonella.

  8. Machine Protection

    CERN Document Server

    Schmidt, R

    2014-01-01

    The protection of accelerator equipment is as old as accelerator technology and was for many years related to high-power equipment. Examples are the protection of powering equipment from overheating (magnets, power converters, high-current cables), of superconducting magnets from damage after a quench and of klystrons. The protection of equipment from beam accidents is more recent. It is related to the increasing beam power of high-power proton accelerators such as ISIS, SNS, ESS and the PSI cyclotron, to the emission of synchrotron light by electron–positron accelerators and FELs, and to the increase of energy stored in the beam (in particular for hadron colliders such as LHC). Designing a machine protection system requires an excellent understanding of accelerator physics and operation to anticipate possible failures that could lead to damage. Machine protection includes beam and equipment monitoring, a system to safely stop beam operation (e.g. dumping the beam or stopping the beam at low energy) and an ...

  9. Effect of Pre-treatment with Moringa oleifera (Drumstick Leaves on Diabetogenesis Produced by Alloxan in Rats

    Directory of Open Access Journals (Sweden)

    Shamsun Nahar

    2015-07-01

    Full Text Available Background: Medicinal plants constitute an important source of potential therapeutic agents for diabetes. Objective: In the study, we aimed to investigate the pre-treatment effect or preventive effects of Moringa oleifera (MO leaves on blood sugar of rats. Materials and method: This experimental study was carried out in the department of Pharmacology and Therapeutics of Sir Salimullah Medical College in collaboration with Bangladesh Council of Scientific and Industrial Research (BCSIR, Dhaka. A total 24 long Evans rats were included in this study and divided in to four groups. Hyperglycemia was induced on rats using alloxan (100 mg/kg body weight, intraperitioneally. Blood sample was collected from tail vein by tail tipping method. Pre-treatment effect or preventive role of Moringa oleifera (drumstick leaf powder on diabetogenesis produced by Alloxan in rats was tested by giving 50 mg/rat/day Moringa oleifera leaf powder for 14 days orally as pre-treatment along with standard rat feed. Then alloxan was administered intraperitoneally on 15th day of the experiment and 50mg/rat/day Moringa oleifera leaf powder was given for 7 days as post-treatment. Results: No significant effect of MO on blood glucose level was observed on normal rats and non significant hypoglycaemic effect was found in rats that were pretreated with MO. Conclusion: The present study suggests that Moringa oleifera leaf powder did not produce any significant protective effect in diabetogenesis produced by alloxan though it has hypoglycaemic effect.

  10. Pretreatment with Fish Oil-Based Lipid Emulsion Modulates Muscle Leukocyte Chemotaxis in Murine Model of Sublethal Lower Limb Ischemia

    Science.gov (United States)

    Shih, Yao-Ming; Shih, Juey-Ming; Yeh, Chiu-Li; Li, Cheng-Che

    2017-01-01

    This study investigated the effects of a fish oil- (FO-) based lipid emulsion on muscle leukocyte chemotaxis and inflammatory responses in a murine model of limb ischemia-reperfusion (IR) injury. Mice were assigned randomly to 1 sham (sham) group, 2 ischemic groups, and 2 IR groups. The sham group did not undergo the ischemic procedure. The mice assigned to the ischemic or IR groups were pretreated intraperitoneally with either saline or FO-based lipid emulsion for 3 consecutive days. The IR procedure was induced by applying a 4.5 oz orthodontic rubber band to the left thigh above the greater trochanter for 120 min and then cutting the band to allow reperfusion. The ischemic groups were sacrificed immediately while the IR groups were sacrificed 24 h after reperfusion. Blood, IR-injured gastrocnemius, and lung tissues were collected for analysis. The results showed that FO pretreatment suppressed the local and systemic expression of several IR-induced proinflammatory mediators. Also, the FO-pretreated group had lower blood Ly6ChiCCR2hi monocyte percentage and muscle M1/M2 ratio than the saline group at 24 h after reperfusion. These findings suggest that FO pretreatment may have a protective role in limb IR injury by modulating the expression of proinflammatory mediators and regulating the polarization of macrophage. PMID:28182087

  11. Enteral glutamine pretreatment does not decrease plasma endotoxin level induced by ischemia-reperfusion injury in rats

    Institute of Scientific and Technical Information of China (English)

    Arda Demirkan; Erkin Orazakunov; Berna Savas; M Ayhan Kuzu; Mehmet Melli

    2008-01-01

    AIM: To investigate whether oral glutamine pretreatment prevents impairment of intestinal mucosal integrity during ischemia-reperfusion (I/R) in rats. METHODS: The study was performed as two series with 40 rats in each. Each series of animals was divided into four groups. The first group was used as a control. Animals in the second group were only pretreated with oral glutamine, 1 g/kg for 4 d. The third group received a normal diet, and underwent intestinal I/R, while the fourth group was pretreated with oral glutamine in the same way, and underwent intestinal I/R. Intestinal mucosal permeability to 51Cr-labeled EDTA was measured in urine in the first series of animals. In the second series, histopathological changes in intestinal tissue and plasma endotoxin levels were evaluated. RESULTS: Intestinal I/R produced a significant increase in intestinal permeability, plasma endotoxin level and worsened histopathological alterations. After intestinal I/R, permeability was significantly lower in glutamine- treated rats compared to those which received a normal diet. However, no significant change was observed in plasma endotoxin levels or histopathological findings. CONCLUSION: Although glutamine pretreatment seems to be protective of intestinal integrity, upon I/R injury, such an effect was not observable in the histopathological changes or plasma endotoxin level.

  12. Comparison of aqueous ammonia and dilute acid pretreatment of bamboo fractions: Structure properties and enzymatic hydrolysis.

    Science.gov (United States)

    Xin, Donglin; Yang, Zhong; Liu, Feng; Xu, Xueru; Zhang, Junhua

    2015-01-01

    The effect of two pretreatments methods, aqueous ammonia (SAA) and dilute acid (DA), on the chemical compositions, cellulose crystallinity, morphologic change, and enzymatic hydrolysis of bamboo fractions (bamboo yellow, timber, green, and knot) was compared. Bamboo fractions with SAA pretreatment had better hydrolysability than those with DA pretreatment. High crystallinity index resulted in low hydrolysis yield in the conversion of SAA pretreated bamboo fractions, not DA pretreated fractions. The increase of cellulase loading had modestly positive effect in the hydrolysis of both SAA and DA pretreated bamboo fractions, while supplement of xylanase significantly increased the hydrolysis of the pretreated bamboo fractions, especially after SAA pretreatment. The results indicated that SAA pretreatment was more effective than DA pretreatment in conversion of bamboo fractions, and supplementation of xylanase was necessary in effective conversion of the SAA pretreated fractions into fermentable sugars.

  13. New pentose dimers with bicyclic moieties from pretreated biomass

    DEFF Research Database (Denmark)

    Rasmussen, H.; Sørensen, Henrik Rokkjær; Tanner, David Ackland

    2017-01-01

    In lignocellulosic biorefinery processes involving enzyme catalysed reactions it is a challenge that enzyme inhibiting compounds are generated and liberated during pretreatment of the biomass. In this study the contribution to cellulase inhibition from xylooligosaccharides and newly discovered ol...

  14. Effect of ultrasonic pretreatment on emulsion polymerization of styrene.

    Science.gov (United States)

    Nagatomo, Daichi; Horie, Takafumi; Hongo, Chizuru; Ohmura, Naoto

    2016-07-01

    This study investigated the effect of pretreatment of ultrasonic irradiation on emulsion polymerization of styrene to propose a process intensification method which gives high conversion, high reaction rate, and high energy efficiency. The solution containing styrene monomer was irradiated by a horn mounted on the ultrasonic transducer with the diameter of 5mm diameter and the frequency of 28 kHz before starting polymerization. The pretreatment of ultrasound irradiation as short as 1 min drastically improved monomer dispersion and increased reaction rate even under the agitation condition with low rotational speed of impeller. Furthermore, the ultrasonic pretreatment resulted in higher monomer concentration in polymer particles and produced larger polymer particles than conventional polymerization without ultrasonic pretreatment.

  15. Enzymatic hydrolysis of pretreated barley and wheat straw

    DEFF Research Database (Denmark)

    Rosgaard, Lisa

    2007-01-01

    pretreatment conditions; hot water extraction and acid- or water impregnation followed by steam explosion showed there were slight differences between the effect of pretreatment conditions in relation to the overall yield from enzymatic hydrolysis. The highest glucose concentration was found for barley straw...... subjected to acid impregnation followed by steam explosion; however when the glucose concentration was related to the glucose potential in the substrates, the highest yield was obtained with hot water extracted. Analysis of the supernatants from the pretreatments by mass spectrometry showed that the water...... feeding strategy to increase the substrate loading in the hydrolysis reaction. The substrate for the enzymatic hydrolysis was primarily steam pretreated wheat and barley straw since these substrates were the primary feedstocks for the Babilafuente Bioethanol process. The initial work showed...

  16. OPTIMIZATION OF LIME PRETREATMENT FOR ENZYMATIC SACCHARIFICATION OF WHEAT STRAW

    Directory of Open Access Journals (Sweden)

    Miroslav Ondrejovič

    2014-02-01

    Full Text Available The aim of this work was optimization of lime pretreatment parameters such as temperature, time and reaction ratio to maximization of reducing saccharide yields occurred by enzyme hydrolysis of pretreated plant material (wheat straw. Pretreatment conditions were optimized using response surface methodology. The optimal conditions were chosen to promote reducing saccharide yields following enzymatic digestion and they were temperature 91.5 °C, time 2.4 hours and reaction ratio 19.7 mL to 1 g of treated wheat straw. The experimental values agreed with predicted within a 95 % confidence interval. The computed model of wheat straw pretreatment by lime can be used for the effective utilization of secondary products obtained in agriculture sector.

  17. Carbohydrate degradation mechanisms and compounds from pretreated biomass

    DEFF Research Database (Denmark)

    Rasmussen, Helena

    ) Liquors from biomass pretreatment contain an array of hitherto unidentified cellulase* inhibitors that are believed to be reaction products from carbohydrate degradation. (*cellulases include endo-cellulases, cellobiohydrolases, LPMO, and beta-glucosidase enzyme activities) Furthermore the two following...... xylose from hemicellulose in the biomass. Even though oligophenolic degradation compounds were common across biomasses, variations were found in biomass structural elements that were released during pretreatment. Pentoseoligosaccharides from sugar cane bagasse had a more acetylated substitution pattern...... than wheat straw, and in oil palm empty fruit bunches 4-hydroxybenzoic acid was identified to be a variation from a lignin structural elements released during pretreatment. In conclusion it was found that the reactions taking place during pretreatment of biomass are complex and involve both degradation...

  18. 40 CFR 405.116 - Pretreatment standards for new sources.

    Science.gov (United States)

    2010-07-01

    ... GUIDELINES AND STANDARDS DAIRY PRODUCTS PROCESSING POINT SOURCE CATEGORY Condensed Whey Subcategory § 405.116 Pretreatment standards for new sources. Any new source subject to this subpart that introduces...

  19. 40 CFR 405.126 - Pretreatment standards for new sources.

    Science.gov (United States)

    2010-07-01

    ... GUIDELINES AND STANDARDS DAIRY PRODUCTS PROCESSING POINT SOURCE CATEGORY Dry Whey Subcategory § 405.126 Pretreatment standards for new sources. Any new source subject to this subpart that introduces...

  20. Effect of chip size on steam explosion pretreatment of softwood.

    Science.gov (United States)

    Ballesteros, I; Oliva, J M; Navarro, A A; González, A; Carrasco, J; Ballesteros, M

    2000-01-01

    Although considerable progress has been made in technology for converting lignocellulosic biomass into ethanol, substantial opportunities still exist to reduce production costs. In biomass pretreatment, reducing milling power is a technological improvement that will substantially lower production costs for ethanol. Improving sugar yield from hemicellulose hydrolysis would also reduce ethanol production costs. Thus, it would be desirable to test innovative pretreatment conditions to improve the economics by reducing electrical power of the milling stage and by optimizing pretreatment recovery of hemicellulose, as well as to enhance cellulose hydrolysis. The objective of this study was to evaluate the effect of chip size (2-5, 5-8, and 8-12 mm) on steam-explosion pretreatment (190 and 210 degrees C, 4 and 8 min) of softwood (Pinus pinaster).

  1. Photoregulation of Anthocyanin Synthesis : VIII. Effect of Light Pretreatments.

    Science.gov (United States)

    Mancinelli, A L

    1984-06-01

    A comparative study of the spectral sensitivity of anthocyanin production in dark-grown and light-pretreated systems was carried out in Brassica oleracea L., Lycopersicon esculentum Mill., Secale cereale L. and Spirodela polyrrhiza L. Light pretreatments bring about an enhancement of the inductive, red-far red reversible response in all systems, a decrease of the continuous irradiation response in cabbage, rye, and tomato seedlings, and an enhancement of the continuous irradiation response in cabbage leaf disks. Light pretreatments also bring about a marked change in the spectral sensitivity of the continuous irradiation response. The different effect of light pretreatments on the photosensitivity of the response to short and long wavelength irradiations suggests that two photoreceptors, phytochrome and cryptochrome, may be involved in the photoregulation of anthocyanin production.

  2. Pretreatment Cardiometabolic Status in Youth With Early-Onset Psychosis

    DEFF Research Database (Denmark)

    Jensen, Karsten G; Correll, Christoph U; Rudå, Ditte

    2017-01-01

    OBJECTIVE: To describe pretreatment cardiometabolic constitution in children and adolescents with first-episode psychosis (FEP). METHODS: Baseline cardiometabolic assessment was performed in youths aged 12-17 years with FEP entering the Tolerability and Efficacy of Antipsychotics (TEA) trial...

  3. Improving biogas production from microalgae by enzymatic pretreatment.

    Science.gov (United States)

    Passos, Fabiana; Hom-Diaz, Andrea; Blanquez, Paqui; Vicent, Teresa; Ferrer, Ivet

    2016-01-01

    In this study, enzymatic pretreatment of microalgal biomass was investigated under different conditions and evaluated using biochemical methane potential (BMP) tests. Cellulase, glucohydrolase and an enzyme mix composed of cellulase, glucohydrolase and xylanase were selected based on the microalgae cell wall composition (cellulose, hemicellulose, pectin and glycoprotein). All of them increased organic matter solubilisation, obtaining high values already after 6h of pretreatment with an enzyme dose of 1% for cellulase and the enzyme mix. BMP tests with pretreated microalgae showed a methane yield increase of 8 and 15% for cellulase and the enzyme mix, respectively. Prospective research should evaluate enzymatic pretreatments in continuous anaerobic reactors so as to estimate the energy balance and economic cost of the process.

  4. Wet oxidation pretreatment of rape straw for ethanol production

    DEFF Research Database (Denmark)

    Arvaniti, Efthalia; Bjerre, Anne Belinda; Schmidt, Jens Ejbye

    2012-01-01

    Rape straw can be used for production of second generation bioethanol. In this paper we optimized the pretreatment of rape straw for this purpose using Wet oxidation (WO). The effect of reaction temperature, reaction time, and oxygen gas pressure was investigated for maximum ethanol yield via...... Simultaneous Saccharification and Fermentation (SSF). To reduce the water use and increase the energy efficiency in WO pretreatment features like recycling liquid (filtrate), presoaking of rape straw in water or recycled filtrate before WO, skip washing pretreated solids (filter cake) after WO, or use of whole...... slurry (Filter cake + filtrate) in SSF were also tested. Except ethanol yields, pretreatment methods were evaluated based on achieved glucose yields, amount of water used, recovery of cellulose, hemicellulose, and lignin.The highest ethanol yield obtained was 67% after fermenting the whole slurry...

  5. Pretreatment and fractionation of wheat straw using various ionic liquids

    OpenAIRE

    Lopes,André; João, Karen; Bogel-Lukasik, Ewa; Roseiro, Luísa; Bogel-Lukasik, R.

    2013-01-01

    Pretreatment of lignocellulosic biomass with ionic liquids (ILs) is a promising and challenging process for an alternative method of biomass processing. The present work emphasizes the examination of wheat straw pretreatment using ILs, namely, 1-butyl-3-methylimidazolium hydrogensulfate ([bmim][HSO4]), 1-butyl-3-methylimidazolium thiocyanate ([bmim]-[SCN]), and 1-butyl-3-methylimidazolium dicyanamide ([bmim][N(CN)2]). Only [bmim][HSO4] was found to achieve a macroscopic complete dissolution o...

  6. Anaerobic biodegradability of dairy wastewater pretreated with porcine pancreas lipase

    OpenAIRE

    2010-01-01

    Lipids-rich wastewater was partial hydrolyzed with porcine pancreas lipase and the efficiency of the enzymatic pretreatment was verified by the comparative biodegradability tests (crude and treated wastewater). Alternatively, simultaneous run was carried out in which hydrolysis and digestion was performed in the same reactor. Wastewater from dairy industries and low cost lipase preparation at two concentrations (0.05 and 0.5% w.v-1) were used. All the samples pretreated with enzyme showed a p...

  7. Micronutrient dynamics after thermal pretreatment of olive mill solid waste.

    Science.gov (United States)

    Almansa, Ana R; Rodriguez-Galan, Monica; Borja, Rafael; Fermoso, Fernando G

    2015-09-01

    This study investigated metal dynamics, and their bioavailability, before and after thermal pretreatment of olive mill solid waste (OMSW), using a sequential metal extraction scheme. The 11.5% increase of cobalt in the most available fraction after the pretreatment coupled to the increase of methane production rate have been a good indicator that the OMSW anaerobic digestion might be metal limited due to the lack of cobalt.

  8. Protection Myopia

    DEFF Research Database (Denmark)

    Laursen, Keld; Salter, Ammon; Li, Cher

    The strategies firms use to protect their intellectual property and knowledge can strongly influence their ability to capture the benefits of their innovative efforts. Using the attention-based theory, we explore positive and negative sides of legal appropriability. While asserting the benefits f...

  9. Enhancement of Enzymatic Saccharification of Poplar by Green Liquor Pretreatment

    Directory of Open Access Journals (Sweden)

    Xin Meng

    2014-04-01

    Full Text Available Green liquor (Na2S + Na2CO3, GL pretreatment is an effective pathway for improving the enzymatic digestibility of lignocellulosic biomass for the production of bioethanol. In this work, GL was employed as a pretreatment to enhance the enzymatic saccharification of poplar. During pretreatment, the increase of H-factor and TTA charge resulted in enhanced delignification and increased degradation of polysaccharides. The sugar yield of enzymatic hydrolysis increased rapidly with increasing TTA charge in GL pretreatment, while the effect of different H-factors (from 400 to 800 on sugar yield was unnoticeable. The pretreated solid recovery was 75.5% at a lignin removal rate of 29.2% under optimized conditions of total titratable alkali (TTA charge 20%, sulfidity 25%, and H-factor 400. The sugar yield of glucan, xylan, and total sugar of GL-pretreated poplar in enzymatic hydrolysis reached up to 89.9%, 65.5%, and 82.8%, respectively, at a cellulase loading of 40 FPU/g-cellulose.

  10. Combined alkaline and ultrasonic pretreatment of sludge before aerobic digestion

    Institute of Scientific and Technical Information of China (English)

    JIN Yiying; LI Huan; MAHAR Rasool Bux; WANG Zhiyu; NIE Yongfeng

    2009-01-01

    Alkaline and ultrasonic sludge disintegration can both be used as pretreatments of waste activated sludge (WAS) for improving the subsequent anaerobic or aerobic digestion. The pretreatment has been carried out using different combination of these two methods in this study. The effect was evaluated based on the quantity of soluble chemical oxygen demand (SCOD) in the pretreated sludge as well as the degradation of organic matter in the following aerobic digestion. For WAS samples with combined pretreatment, the released COD was in high level than those with ultrasonic or alkaline treatment. When combined with the same ultrasonic treatment, NaOH treatment resulted in more solubilization of WAS than Ca(OH)2. For combined NaOH and ultrasonic treatments with different sequences, the released COD were in the order: simultaneous treatment > ultrasonic treatment following NaOH treatment > NaOH treatment following ultrasonic treatment. For simultaneous treatment, low NaOH dosage (100 g/kg dry solid), short duration (30 min) of NaOH treatment, and low ultrasonic specific energy (7 500 kJ/kg dry solid) were beneficial for sludge disintegration. Using combined NaOH and ultrasonic pretreatment with the optimium parameters, the degradation efficiency of organic matter was increased from 38.0% to 50.7%, which is much higher than with ultrasonic (42.5%) or with NaOH pretreatment (43.5%) in the subsequent aerobic digestion at the same retention time.

  11. New prospects in pretreatment of cotton fabrics using microwave heating.

    Science.gov (United States)

    Hashem, M; Taleb, M Abou; El-Shall, F N; Haggag, K

    2014-03-15

    As microwaves are known to give fast and rapid volume heating, the present study is undertaken to investigate the use of microwave heating for pretreatment cotton fabrics to reduce the pretreatment time, chemicals and water. The onset of the microwave heating technique on the physicochemical and performance properties of desized, scoured and bleached cotton fabric is elucidated and compared with those obtained on using conventional thermal heating. Combined one-step process for desizing, scouring and bleaching of cotton fabric under microwave heating was also investigated. The dual effect of adding urea, (as microwave absorber and hydrogen peroxide activator) has been exploiting to accelerate the pretreatment reaction of cotton fabric. DSC, FT-IR and SEM have been used to investigate the onset of microwave on the morphological and chemical change of cotton cellulose after pretreatment and bleaching under microwave heating. Results obtained show that, a complete fabric preparation was obtained in just 5 min on using microwave in pretreatments process and the fabric properties were comparable to those obtained in traditional pretreatment process which requires 2.5-3h for completion.

  12. Simultaneous saccharification and cofermentation of peracetic acid-pretreated biomass.

    Science.gov (United States)

    Teixeira, L C; Linden, J C; Schroeder, H A

    2000-01-01

    Previous work in our laboratories has demonstrated the effectiveness of peracetic acid for improving enzymatic digestibility of lignocellulosic materials. The use of dilute alkali solutions as a pre-pretreatment prior to peracetic acid lignin oxidation increased carbohydrate hydrolysis yields in a synergistic as opposed to additive manner. Deacetylation of xylan is easily achieved using dilute alkali solutions under mild conditions. In this article, we evaluate the effectiveness of peracetic acid combined with an alkaline pre-pretreatment through simultaneous saccharification and cofermentation (SSCF) of pretreated hybrid poplar wood and sugar cane bagasse. Respective ethanol yields of 92.8 and 91.9% of theoretical are achieved using 6% NaOH/15% peracetic acid-pretreated substrates and recombinant Zymomonas mobilis CP4/pZB5. Reduction of acetyl groups of the lignocellulosic materials is demonstrated following alkaline pre-pretreatments. Such processing may be helpful in reducing peracetic acid requirements. The influence of deacetylation is more significant in combined pretreatments using lower peracetic acid loadings.

  13. EDU pretreatment decreases polymorphonuclear leukocyte migration into rat lung airways.

    Science.gov (United States)

    Bassett, D J; Elbon, C L; Ishii, Y; Yang, H; Otterbein, L; Boswell, G A; Kerr, J S

    1994-07-01

    Pretreatment with the heterocyclic compound EDU (N-[2-(2-oxo-1-imidazolindinyl)ethyl]-N'-phenylurea) has previously been shown to reduce polymorphonuclear leukocyte (PMN) infiltration into the airways of ozone-exposed rats. The present study further examined the effects of 1 and 2 days EDU pretreatment on rat lung inflammatory responses by determining PMN infiltration in response to intratracheal instillation with the chemoattractant formyl-norleucine-leucine-phenylalanine (fNLP). Maximal recovery of PMNs by bronchoalveolar lavage was observed 4 hr after fNLP instillation with no alteration in the numbers of recoverable macrophages and lymphocytes. Although 1-day pretreatment with EDU did not affect PMN recovery from fNLP-instilled rat lungs, 2 days of EDU pretreatment prevented PMN infiltration as indicated by PMN recoveries that were similar to those obtained from saline-instilled lungs. Measurements of lung-marginated and interstitial pools of inflammatory cells using collagenase tissue digestion demonstrated no effect of 2 days EDU pretreatment. Although 2 days EDU pretreatment alone did not alter blood PMN content, lung permeability, and the lavage recoveries of inflammatory cells, blood PMN responses to chemotactic stimuli in vitro were impaired. In addition, EDU was shown to directly inhibit PMN chemotaxis and superoxide anion generation in vitro. These data demonstrated that EDU acts by interfering with PMN activation and migration rather than by decreasing PMN availability. EDU, by modulating the inflammatory response, represents a useful compound for preventing PMN-associated amplification of acute lung injuries.

  14. Comparison the effects of nitric oxide and spermidin pretreatment on alleviation of salt stress in chamomile plant (Matricaria recutita L.

    Directory of Open Access Journals (Sweden)

    Fazelian Nasrin

    2012-08-01

    Full Text Available Salt stress is an important environmental stress that produces reactive oxygen species in plants and causes oxidative injuries. In this investigation, salt stress reduced the shoot and root length, while increased the content of malondealdehyde, Hydrogen peroxide, and the activity of Ascorbate peroxidase andguaiacol peroxidase. Pretreatment of chamomile plants under salt stress with sodium nitroprussideand Spermidin caused enhancement of growth parameters and reduction of malondealdehyde and Hydrogen peroxide content. Pretreatment of plants with sodium nitroprusside remarkably increased Ascorbate peroxidase activity, while Spermidin pre-treatment significantly increased guaiacol peroxidase activity. Application of sodium nitroprusside or Spermidin with Methylene blue which is known to block cyclic guanosine monophosphate signaling pathway, reduced the protective effects of sodium nitroprussideand Spermidin in plants under salinity condition. The result of this study indicated that Methylene blue could partially and entirely abolish the protective effect of Nitric oxide on some physiological parameter. Methylene blue also has could reduce the alleviation effect of Spermidin on some of parameters in chamomile plant under salt stress, so with comparing the results of this study it seems that Spermidin probably acts through Nitric oxide pathway, but the use of 2-4- carboxyphenyl- 4,4,5,5- tetramethyl-imidazoline-1-oxyl-3-oxide is better to prove.

  15. Biomass pretreatment affects Ustilago maydis in producing itaconic acid

    Directory of Open Access Journals (Sweden)

    Klement Tobias

    2012-04-01

    Full Text Available Abstract Background In the last years, the biotechnological production of platform chemicals for fuel components has become a major focus of interest. Although ligno-cellulosic material is considered as suitable feedstock, the almost inevitable pretreatment of this recalcitrant material may interfere with the subsequent fermentation steps. In this study, the fungus Ustilago maydis was used to produce itaconic acid as platform chemical for the synthesis of potential biofuels such as 3-methyltetrahydrofuran. No studies, however, have investigated how pretreatment of ligno-cellulosic biomass precisely influences the subsequent fermentation by U. maydis. Thus, this current study aims to first characterize U. maydis in shake flasks and then to evaluate the influence of three exemplary pretreatment methods on the cultivation and itaconic acid production of this fungus. Cellulose enzymatically hydrolysed in seawater and salt-assisted organic-acid catalysed cellulose were investigated as substrates. Lastly, hydrolysed hemicellulose from fractionated beech wood was applied as substrate. Results U. maydis was characterized on shake flask level regarding its itaconic acid production on glucose. Nitrogen limitation was shown to be a crucial condition for the production of itaconic acid. For itaconic acid concentrations above 25 g/L, a significant product inhibition was observed. Performing experiments that simulated influences of possible pretreatment methods, U. maydis was only slightly affected by high osmolarities up to 3.5 osmol/L as well as of 0.1 M oxalic acid. The production of itaconic acid was achieved on pretreated cellulose in seawater and on the hydrolysed hemicellulosic fraction of pretreated beech wood. Conclusion The fungus U. maydis is a promising producer of itaconic acid, since it grows as single cells (yeast-like in submerged cultivations and it is extremely robust in high osmotic media and real seawater. Moreover, U. maydis can grow on

  16. Protective coatings for commercial particulates

    DEFF Research Database (Denmark)

    Kindl, B.; Teng, Y.H.; Liu, Y.L.

    1994-01-01

    SiC/Al composites are in large-scale production with Al-Si alloy matrices. The same composites with pure Al or low Si matrices need diffusion barriers on the SiC reinforcement to control the interfacial reaction. The present paper describes various approaches taken to obtain protective coatings...... of alumina and zirconia on SiC particulates by sol-gel techniques. Aqueous and organic precursors have been used. The extent of the reaction, i.e., the Si and Al4C3 content in the matrix, was determined by differential thermal analysis and X-ray diffraction. The reaction rates of some coated particulates...... in liquid Al are decreased by as much as one order of magnitude during the first 15 min of immersion. Pretreatments of the SiC surface, the composition and thickness of the coating interphase and heat treatments of the coated materials have been studied, and are discussed in relation to their effect...

  17. Radiation protection

    CERN Multimedia

    Radioactive Shipping Service

    2005-01-01

    The section of the radiation protection group in charge of shipping radioactive material would like to remind users that all radioactive material leaving CERN must be checked for radioactivity and must be shipped according to the procedure given at http://cern.ch/service-rp-shipping Do not hesitate to contact us for any question or control. Radioactive Shipping Service: service-rp-shipping@cern.ch Tél. 73171

  18. Radiation protection

    CERN Document Server

    2005-01-01

    The section of the Radiation Protection Group in charge of shipping radioactive material would like to remind users that all radioactive material leaving CERN must be checked for radioactivity and must be shipped according to the procedure given at http://cern.ch/service-rp-shipping Do not hesitate to contact us for any question or control. Radioactive Shipping Service: service-rp-shipping@cern.ch Tel. 73171

  19. Radiation protection

    CERN Multimedia

    2005-01-01

    The section of the Radiation Protection Group in charge of shipping radioactive material would like to remind users that all radioactive material leaving CERN must be checked for radioactivity and must be shipped according to the procedure given at http://cern.ch/service-rp-shipping Do not hesitate to contact us for any question or control. Radioactive Shipping Service: service-rp-shipping@cern.ch Tél. 73171

  20. Protective Clothing

    Science.gov (United States)

    1975-01-01

    CONTROL NO* /ZOMOS A0-6n9 164 NAVAL AIR ENGINEERING CENTER PHILADELPHIA PA AERONAUTICAL MATERIALS LAB METHODS OF SANITIZING AND DEODORIZING ...SANITIZING, DEODORIZING , AND ANTISTATIC AGENTS IS DESCRIBED* RECOMMENDATIONS ARE MADE FOR THE USE OF QUATERNARY AMMONIUM 1OMPOUNDS FOR SANITIZING AND...EQUIPMENT. HONEYCOMB CORES. SANDWICH CONSTRUCTION, METAL PLATES. ALUMINUM . TESTS. LAND MINES (U) SEVERAL OF THE BLAST PROTECTIVE COMBAT BOOT CONCEPTS

  1. Evaluation of hepatoprotective potential of HESA-A (a marine compound) pretreatment against thioacetamide-induced hepatic damage in rabbits.

    Science.gov (United States)

    Ahmadi, A; Naderi, G; Asgary, S

    2005-01-01

    HESA-A, a marine compound, has been shown to exhibit antihepatic cancer, antitumor and anti-Parkinson effects. The hepatoprotective potential of HESA-A pretreatment at doses of 125 mg and 250 mg per day orally for a period of 40 days was evaluated against thioacetamide-induced liver damage in rabbits. Biochemical parameters such as serum glutamate oxaloacetate transaminase and lactate dehydrogenase in serum were estimated to assess liver function and lipid peroxidation products (malondialdehyde [MDA]) and the antierythrocyte lysis effect of plasma for measurement of antioxidant potential capacity. Data on the hepatic biochemical parameters revealed the hepatoprotective potential of HESA-A pretreatment against thioacetamide-induced hepatotoxicity in rabbits. There was an increase in total antioxidant and antierythrocyte lysis and a decrease in MDA in plasma after HESA-A treatment. These results strongly suggest that HESA-A has a protective action against preoperative damage to biomembranes.

  2. Influences of mechanical pre-treatment on the non-biological treatment of municipal wastewater by forward osmosis

    DEFF Research Database (Denmark)

    Hey, Tobias; Zarebska, Agata; Bajraktari, Niada

    2016-01-01

    Municipal wastewater treatment commonly involves mechanical, biological and chemical treatment steps as state-of-the-art technologies for protecting the environment from adverse effects. The biological treatment step consumes the most energy and can create greenhouse gases. This study investigates...... municipal wastewater treatment without the biological treatment step, including the effects of different pre-treatment configurations, e.g., direct membrane filtration before forward osmosis. Forward osmosis was tested using raw wastewater and wastewater subjected to different types of mechanical pre-treatment......, e.g., microsieving and microfiltration permeation, as a potential technology for municipal wastewater treatment. Forward osmosis was performed using thin-film-composite, Aquaporin Inside(TM) and HTI membranes with NaCl as the draw solution. Both types of forward osmosis membranes were tested...

  3. Pretreatment Engineering Platform (PEP) Integrated Test B Run Report--Caustic and Oxidative Leaching in UFP-VSL-T02A

    Energy Technology Data Exchange (ETDEWEB)

    Geeting, John GH; Bredt, Ofelia P.; Burns, Carolyn A.; Golovich, Elizabeth C.; Guzman-Leong, Consuelo E.; Josephson, Gary B.; Kurath, Dean E.; Sevigny, Gary J.; Aaberg, Rosanne L.

    2009-12-10

    Pacific Northwest National Laboratory (PNNL) has been tasked by Bechtel National Inc. (BNI) on the River Protection Project-Hanford Tank Waste Treatment and Immobilization Plant (RPP-WTP) project to perform research and development activities to resolve technical issues identified for the Pretreatment Facility (PTF). The Pretreatment Engineering Platform (PEP) was designed, constructed and operated as part of a plan to respond to issue M12, “Undemonstrated Leaching Processes” of the External Flowsheet Review Team (EFRT) issue response plan.( ) The PEP is a 1/4.5-scale test platform designed to simulate the WTP pretreatment caustic leaching, oxidative leaching, ultrafiltration solids concentration, and slurry washing processes. The PEP replicates the WTP leaching processes using prototypic equipment and control strategies. The PEP also includes non-prototypic ancillary equipment to support the core processing.

  4. Pretreatment of empty fruit bunch from oil palm for fuel ethanol production and proposed biorefinery process.

    Science.gov (United States)

    Tan, Liping; Yu, Yongcheng; Li, Xuezhi; Zhao, Jian; Qu, Yinbo; Choo, Yuen May; Loh, Soh Kheang

    2013-05-01

    This study evaluates the effects of some pretreatment processes to improve the enzymatic hydrolysis of oil palm empty fruit bunch (EFB) for ethanol production. The experimental results show that the bisulfite pretreatment was practical for EFB pretreatment. Moreover, the optimum pretreatment conditions of the bisulfite pretreatment (180 °C, 30 min, 8% NaHSO3, 1% H2SO4) were identified. In the experiments, a biorefinery process of EFB was proposed to produce ethanol, xylose products, and lignosulfonates.

  5. Study of Enzymatic Hydrolysis of Dilute Acid Pretreated Coconut Husk

    Directory of Open Access Journals (Sweden)

    Rudy Agustriyanto

    2012-12-01

    Full Text Available Coconut husk is classified as complex lignocellulosic material that contains cellulose, hemicellulose, lignin, and some other extractive compounds. Cellulose from coconut husk can be used as fermentation substrate after enzymatic hydrolysis. In contrary, lignin content from the coconut husk will act as an inhibitor in this hydrolysis process. Therefore, a pretreatment process is needed to enhance the hydrolysis of cellulose. The objective of this research is to investigate the production of the glucose through dilute acid pretreatment and to obtain its optimum operating conditions. In this study, the pretreatment was done using dilute sulfuric acid in an autoclave reactor. The pretreatment condition were varied at 80°C, 100°C, 120°C and 0.9%, 1.2%, 1.5% for temperature and acid concentration respectively. The acid pretreated coconut husk was then hydrolyzed using commercial cellulase (celluclast and β-glucosidase (Novozyme 188. The hydrolysis time was 72 hours and the operating conditions were varied at several temperature and pH. From the experimental results it can be concluded that the delignification temperature variation has greater influence than the acid concentration. The optimum operating condition was obtained at pH 4 and 50°C which was pretreated at 100°C using 1.5% acid concentration. Copyright © 2012 by BCREC UNDIP. All rights reserved. (Selected Paper from International Conference on Chemical and Material Engineering (ICCME 2012Received: 28th September 2012, Revised: 2nd October 2012, Accepted: 4th October 2012[How to Cite: R. Agustriyanto, A. Fatmawati, Y. Liasari. (2012. Study of Enzymatic Hydrolysis of Dilute Acid Pretreated Coconut Husk. Bulletin of Chemical Reaction Engineering & Catalysis, 7(2: 137-141. doi:10.9767/bcrec.7.2.4046.137-141] [How to Link / DOI: http://dx.doi.org/10.9767/bcrec.7.2.4046.137-141 ] | View in 

  6. Enhanced fermentable sugar production from kitchen waste using various pretreatments.

    Science.gov (United States)

    Hafid, Halimatun Saadiah; Rahman, Nor'Aini Abdul; Md Shah, Umi Kalsom; Baharudin, Azhari Samsu

    2015-06-01

    The kitchen waste fraction in municipal solid waste contains high organic matter particularly carbohydrate that can contribute to fermentable sugar production for subsequent conversion to bioethanol. This study was carried out to evaluate the influence of single and combination pretreatments of kitchen waste by liquid hot water, mild acid pretreatment of hydrochloric acid (HCl) and sulphuric acid (H2SO4) and enzymatic hydrolysis (glucoamylase). The maximum total fermentable sugar produced after combination pretreatment by 1.5% HCl and glucoamylase consisted of 93.25 g/L glucose, 0.542 g/L sucrose, 0.348 g/L maltose, and 0.321 g/L fructose. The glucose released by the combination pretreatment method was 0.79 g glucose/g KW equivalent to 79% of glucose conversion. The effects of the pre-treatment on kitchen waste indicated that the highest solubilization was 40% by the combination method of 1.5% HCl and glucoamylase. The best combination pre-treatment gave concentrations of lactic acid, acetic acid, and propionic acid of 11.74 g/L, 6.77 g/L, and 1.02 g/L, respectively. The decrease of aliphatic absorbance bands of polysaccharides at 2851 and 2923 cm(-1) and the increase on structures of carbonyl absorbance bands at 1600 cm(-1) reflects the progress of the kitchen waste hydrolysis to fermentable sugars. Overall, 1.5% HCl and glucoamylase treatment was the most profitable process as the minimum selling price of glucose was USD 0.101/g kitchen waste. Therefore, the combination pretreatment method was proposed to enhance the production of fermentable sugar, particularly glucose from kitchen waste as the feedstock for bioethanol production.

  7. Low temperature lignocellulose pretreatment: effects and interactions of pretreatment pH are critical for maximizing enzymatic monosaccharide yields from wheat straw

    DEFF Research Database (Denmark)

    Pedersen, Mads; Johansen, Katja S.; Meyer, Anne S.

    2011-01-01

    C for 10 min. The maximal enzymatic glucose and xylose yields from the solid, pretreated wheat straw fraction were obtained after pretreatments at the most extreme pH values (pH 1 or pH 13) at the maximum pretreatment temperature of 140 degrees C. Surface response models revealed significantly...

  8. Activation of glassy carbon electrodes by photocatalytic pretreatment

    Energy Technology Data Exchange (ETDEWEB)

    Dumanli, Onur [Department of Chemistry, Faculty of Science and Art, Ondokuz Mayis University, Kurupelit, 55139 Samsun (Turkey); Onar, A. Nur [Department of Chemistry, Faculty of Science and Art, Ondokuz Mayis University, Kurupelit, 55139 Samsun (Turkey)], E-mail: nonar@omu.edu.tr

    2009-11-01

    This paper describes a simple and rapid photocatalytic pretreatment procedure that removes contaminants from glassy carbon (GC) surfaces. The effectiveness of TiO{sub 2} mediated photocatalytic pretreatment procedure was compared to commonly used alumina polishing procedure. Cyclic voltammetric and chronocoulometric measurements were carried out to assess the changes in electrode reactivity by using four redox systems. Electrochemical measurements obtained on photocatalytically treated GC electrodes showed a more active surface relative to polished GC. In cyclic voltammograms of epinephrine, Fe(CN){sub 6}{sup 3-/4-} and ferrocene redox systems, higher oxidation and reduction currents were observed. The heterogeneous electron transfer rate constants (k{sup o}) were calculated for Fe(CN){sub 6}{sup 3-/4-} and ferrocene which were greater for photocatalytic pretreatment. Chronocoulometry was performed in order to find the amount of adsorbed methylene blue onto the electrode and was calculated as 0.34 pmol cm{sup -2} for photocatalytically pretreated GC. The proposed photocatalytic GC electrode cleansing and activating pretreatment procedure was more effective than classical alumina polishing.

  9. Intensification of biogas production using pretreatment based on hydrodynamic cavitation.

    Science.gov (United States)

    Patil, Pankaj N; Gogate, Parag R; Csoka, Levente; Dregelyi-Kiss, Agota; Horvath, Miklos

    2016-05-01

    The present work investigates the application of hydrodynamic cavitation (HC) for the pretreatment of wheat straw with an objective of enhancing the biogas production. The hydrodynamic cavitation reactor is based on a stator and rotor assembly. The effect of three different speeds of rotor (2300, 2500, 2700 rpm), wheat straw to water ratios (0.5%, 1% and 1.5% wt/wt) and also treatment times as 2, 4 and 6 min have been investigated in the work using the design of experiments (DOE) approach. It was observed that the methane yield of 31.8 ml was obtained with untreated wheat straw whereas 77.9 ml was obtained with HC pre-treated wheat straw confirming the favourable changes during the pre-treatment. The combined pre-treatment using KOH and HC gave maximum yield of biogas as 172.3 ml. Overall, it has been established that significant enhancement in the biogas production can be obtained due to the pretreatment using HC which can also be further intensified by combination with chemical treatment.

  10. Effect of pretreating of host oil on coprocessing

    Energy Technology Data Exchange (ETDEWEB)

    Hajdu, P.E.; Tierney, J.W.; Wender, I. [Univ. of Pittsburgh, PA (United States)

    1995-12-31

    The principal objective of this research was to determine if coprocessing performance (i.e., coal conversion and oil yield) could be significantly improved by pretreating the heavy resid prior to reacting it with coal. For this purpose, two petroleum vacuum resids (1000{degrees}F+), one from the Amoco Co. and another from the Citgo Co., were used as such and after they had been pretreated by catalytic hydrogenation and hydrocracking reactions. The pretreatments were aimed at improving the host oil by; (1) converting any aromatic structures in the petroleum to hydroaromatic compounds capable of donating hydrogen, (2) cracking the heavy oil to lower molecular weight material that might serve as a better solvent, (3) reducing the coking propensity of the heavy oil through the hydrogenation of polynuclear aromatic compounds, and (4) removing metals and heteroatoms that might poison a coprocessing catalyst. Highly dispersed catalysts, including fine particle Fe- and Mo-based, and dicobalt octacarbonyl, Co{sub 2}(CO){sub 8}, were used in this study. The untreated and pretreated resids were extensively characterized in order to determine chemical changes brought about by the pretreatments. The modified heavy oils were then coprocessed with an Illinois No. 6 coal as well as with a Wyodak coal, and compared to coprocessing with untreated resids under the same hydroliquefaction conditions. The amount of oil derived from coal was estimated by measuring the level of phenolic oxygen (derived mainly from coal) present in the oil products. Results are presented and discussed.

  11. Pretreatment of moso bamboo with dilute phosphoric acid

    Directory of Open Access Journals (Sweden)

    Bo Hong

    2012-11-01

    Full Text Available Dilute phosphoric acid pretreatment of moso bamboo materials was studied for producing high quality dissolving pulp for textile applications. The dynamics of dilute acid pretreatment were considered. The Saeman model was found to describe well the acid hydrolysis of moso bamboo hemicelluloses to their monomers under different temperatures and different dilute phosphoric acid concentrations. The initial degradation rate of hemicelluloses was much higher than its subsequent degradation rate, and the xylose generation rate increased with increasing temperature. The change rule of the pentose extraction rate was considered along with the pretreatment factor (P factor. Optimum dilute acid pretreatment conditions were 170 °C and 45 minutes. Based on the optimum conditions and a mass balance of sugars, a weight loss of 26.5% of the solid and liquid fractions combined was observed after the pretreatment. SEM results revealed that the moso bamboo fibers surfaces and cell wall were damaged. With the surface area increasing, the accessible pore areas also increased. At the same time, the crystallinity of the cellulose was reduced, which created a favorable environment for chemical penetration in the subsequent treatment.

  12. Specific pretreatments reduce curing period of vanilla (Vanilla planifolia) beans.

    Science.gov (United States)

    Sreedhar, R V; Roohie, K; Venkatachalam, L; Narayan, M S; Bhagyalakshmi, N

    2007-04-18

    With the aiming of reducing the curing period, effects of pretreatments on flavor formation in vanilla beans during accelerated curing at 38 degrees C for 40 days were studied. Moisture loss, change in texture, levels of flavoring compounds, and activities of relevant enzymes were compared among various pretreatments as well as the commercial sample. Use of naphthalene acetic acid (NAA; 5 mg/L) or Ethrel (1%) with blanching pretreatment resulted in 3-fold higher vanillin on the 10th day. Other flavoring compounds-vanillic acid, p-hydroxybenzoic acid, and p-hydroxybenzaldehyde-fluctuated greatly, showing no correlation with the pretreatments. Scarification of beans resulted in nearly 4- and 3.6-fold higher vanillin formations on the 10th day in NAA- and Ethrel-treated beans, respectively, as compared to control with a significant change in texture. When activities of major relevant enzymes were followed, addition of NAA or Ethrel helped to retain higher levels of cellulase throughout the curing period and higher levels of beta-glucosidase on the 20th day that correlated with higher vanillin content during curing and subsequent periods. Peroxidase, being highest throughout, did not correlate with the change in levels of major flavoring compounds. The pretreatment methods of the present study may find importance for realizing higher flavor formation in a shorter period because the major quality parameters were found to be comparable to those of a commercial sample.

  13. Feasibility of hydrothermal pretreatment on maize silage for bioethanol production.

    Science.gov (United States)

    Xu, Jian; Thomsen, Mette Hedegaard; Thomsen, Anne Belinda

    2010-09-01

    The potential of maize silage as a feedstock to produce bioethanol was evaluated in the present study. The hydrothermal pretreatment with five different pretreatment severity factors (PSF) was employed to pretreat the maize silage and compared in terms of sugar recovery, toxic test, and ethanol production by prehydrolysis and simultaneous saccharification and fermentation. After pretreatment, most of the cellulose remained in the residue, ranging between 85.87% by the highest PSF (185 degrees C, 15 min) and 92.90% obtained at the lowest PSF (185 degrees C, 3 min). A larger part of starch, varying from 71.64% by the highest PSF to 78.28% by the lowest, was liberated into liquor part, leaving 8.05-11.74% in the residues. Xylan recovery in the residues increased from 44.25% at the highest PSF to 82.95% at the lowest. The recovery of xylan in liquor changed from 20.13% to 50.33%. Toxic test indicated that all the liquors from the five conditions were not toxic to the Baker's yeast. Pretreatment under 195 degrees C for 7 min had the similar PSF with that of 185 degrees C for 15 min, and both gave the higher ethanol concentration of 19.92 and 19.98 g/L, respectively. The ethanol concentration from untreated maize silage was only 7.67 g/L.

  14. Compounds inhibiting the bioconversion of hydrothermally pretreated lignocellulose.

    Science.gov (United States)

    Ko, Ja Kyong; Um, Youngsoon; Park, Yong-Cheol; Seo, Jin-Ho; Kim, Kyoung Heon

    2015-05-01

    Hydrothermal pretreatment using liquid hot water, steam explosion, or dilute acids enhances the enzymatic digestibility of cellulose by altering the chemical and/or physical structures of lignocellulosic biomass. However, compounds that inhibit both enzymes and microbial activity, including lignin-derived phenolics, soluble sugars, furan aldehydes, and weak acids, are also generated during pretreatment. Insoluble lignin, which predominantly remains within the pretreated solids, also acts as a significant inhibitor of cellulases during hydrolysis of cellulose. Exposed lignin, which is modified to be more recalcitrant to enzymes during pretreatment, adsorbs cellulase nonproductively and reduces the availability of active cellulase for hydrolysis of cellulose. Similarly, lignin-derived phenolics inhibit or deactivate cellulase and β-glucosidase via irreversible binding or precipitation. Meanwhile, the performance of fermenting microorganisms is negatively affected by phenolics, sugar degradation products, and weak acids. This review describes the current knowledge regarding the contributions of inhibitors present in whole pretreatment slurries to the enzymatic hydrolysis of cellulose and fermentation. Furthermore, we discuss various biological strategies to mitigate the effects of these inhibitors on enzymatic and microbial activity to improve the lignocellulose-to-biofuel process robustness. While the inhibitory effect of lignin on enzymes can be relieved through the use of lignin blockers and by genetically engineering the structure of lignin or of cellulase itself, soluble inhibitors, including phenolics, furan aldehydes, and weak acids, can be detoxified by microorganisms or laccase.

  15. ALA Pretreatment Improves Waterlogging Tolerance of Fig Plants.

    Directory of Open Access Journals (Sweden)

    Yuyan An

    Full Text Available 5-aminolevulinic acid (ALA, a natural and environmentally friendly plant growth regulator, can improve plant tolerance to various environmental stresses. However, whether ALA can improve plant waterlogging tolerance is unknown. Here, we investigated the effects of ALA pretreatment on the waterlogging-induced damage of fig (Ficus carica Linn. plants, which often suffer from waterlogging stress. ALA pretreatment significantly alleviated stress-induced morphological damage, increased leaf relative water content (RWC, and reduced leaf superoxide anion ([Formula: see text] production rate and malonaldehyde (MDA content in fig leaves, indicating ALA mitigates waterlogging stress of fig plants. We further demonstrated that ALA pretreatment largely promoted leaf chlorophyll content, photosynthetic electron transfer ability, and photosynthetic performance index, indicating ALA significantly improves plant photosynthetic efficiency under waterlogging stress. Moreover, ALA pretreatment significantly increased activities of leaf superoxide dismutase (SOD and peroxidase (POD, root vigor, and activities of root alcohol dehydrogenase (ADH, and lactate dehydrogenase (LDH, indicating ALA also significantly improves antioxidant ability and root function of fig plants under waterlogging stress. Taken together, ALA pretreatment improves waterlogging tolerance of fig plants significantly, and the promoted root respiration, leaf photosynthesis, and antioxidant ability may contribute greatly to this improvement. Our data firstly shows that ALA can improve plant waterlogging tolerance.

  16. Protecting Antarctica

    Science.gov (United States)

    Carlowicz, Michael

    House Science Committee Chairman Robert Walker (R-Pa.) has introduced a bill into Congress to give the United States the legislative authority to implement the 1991 Environmental Protocol to the Antarctic Treaty. That protocol established rules and principles to shield the Antarctic environment from human spoilage—placing limits on the discharge of pollutants, protecting plant and animal life, and requiring environmental impact assessments before new activities and programs are launched. The protocol also forbids prospecting or developing of mineral resources except for scientific research.

  17. Pretreatment with nitric oxide reduces lead toxicity in cowpea (Vigna unguiculata [L.] walp.

    Directory of Open Access Journals (Sweden)

    Sadeghipour Omid

    2016-01-01

    Full Text Available Lead (Pb is one of the most important toxic heavy metals that reduce plant growth and development. Therefore, finding compounds that can alleviate the toxic effects of Pb is necessary. Nitric oxide (NO is a signaling molecule that plays important roles in different physiological processes in plants, such as the response to biotic and abiotic stresses. A pot experiment was conducted to study the effects of exogenously applied NO on Pb stress tolerance in cowpea. Seeds were soaked at various concentrations of sodium nitroprusside (SNP; NO donor (0, 0.5 and 1 mM for 20 h, and then sown in pots containing 0 or 200 mg kg-1 Pb (NO32. The obtained results showed that Pb stress significantly reduced the chlorophyll value, relative water content (RWC and net photosynthetic rate, but increased lipid peroxidation, proline content and superoxide dismutase (SOD, catalase (CAT, ascorbate peroxidase (APX and glutathione reductase (GR activities. Nonetheless, different levels of NO significantly lowered Pb toxicity by further increasing SOD, CAT, APX and GR activities as well as proline accumulation. NO pretreatment also raised the chlorophyll value, RWC and net photosynthetic rate but reduced lipid peroxidation. Both NO levels (0.5 and 1 mM were effective in Pb stress tolerance; however, 0.5 mM was more effective. These results indicate that NO pretreatment plays an important role in protecting cowpea plants against Pb toxicity by enhancing antioxidant enzyme activities and proline accumulation.

  18. Pretreatment of Cisplatin in Recipients Attenuates Post-Transplantation Pancreatitis in Murine Model

    Directory of Open Access Journals (Sweden)

    Sheng Yan, Yuan Ding, Fei Sun, Zhongjie Lu, Liang Xue, Xiangyan Liu, Mingqi Shuai, Chen Fang, Yan Wang, Hui Cheng, Lin Zhou, Ming H Zheng, Shusen Zheng

    2012-01-01

    Full Text Available Pancreas transplantation is the definite treatment for type 1 diabetes that enables the achievement of long-term normoglycemia and insulin independence. However Post-Transplantation Pancreatitis (PTP due to ischemia reperfusion (IR injury and preservation is a major complication in pancreas transplantation. Owning the potential anti-inflammatory effect of Cisplatin (Cis in liver IR injury, we have examined if Cis could attenuate PTP using a murine model. We found that Cis is able to prevent inflammatory response in PTP. Pretreatment of Cis in recipient mice reduce the impairments of the grafts and hyperamylasimea in the recipients. We documented that the protective mechanism of Cis in PTP involves improvement of microcirculation, reduction of the mononuclear cellular infiltration and apoptosis, suppression of inflammatory cytokine-cascade and inhibition of translocation of high-motility group box protein-1 (HMGB-1 from nucleus to cytoplasm. In short, our study demonstrated that pretreatment of Cis in recipients may reduce the onset of PTP in pancreas transplantation.

  19. Mandarin peel wastes pretreatment with steam explosion for bioethanol production.

    Science.gov (United States)

    Boluda-Aguilar, María; García-Vidal, Lidia; González-Castañeda, Fayiny Del Pilar; López-Gómez, Antonio

    2010-05-01

    The mandarin (Citrus reticulata L.) citrus peel wastes (MCPW) were studied for bioethanol production, obtaining also as co-products: d-limonene, galacturonic acid, and citrus pulp pellets (CPP). The steam explosion pretreatment was analysed at pilot plant level to decrease the hydrolytic enzymes requirements and to separate and recover the d-limonene. The effect of steam explosion on MCPW lignocellulosic composition was analyzed by means thermogravimetric analysis. The d-limonene contents and their influence on ethanol production have been also studied, while concentration of sugars, galacturonic acid and ethanol have been analysed to measure the saccharification and fermentation (HF and SSF) processes efficiency obtained by MCPW steam explosion pretreatment. Ethanol contents of 50-60L/1000kg raw MCPW can be obtained and CPP yields can be regulated by means the control of enzymes dose and the steam explosion pretreatment which can significantly reduce the enzymes requirements.

  20. Pretreatment of paper tube residuals for improved biogas production.

    Science.gov (United States)

    Teghammar, Anna; Yngvesson, Johan; Lundin, Magnus; Taherzadeh, Mohammad J; Horváth, Ilona Sárvári

    2010-02-01

    Paper tube residuals, which are lignocellulosic wastes, have been studied as substrate for biogas (methane) production. Steam explosion and nonexplosive hydrothermal pretreatment, in combination with sodium hydroxide and/or hydrogen peroxide, have been used to improve the biogas production. The treatment conditions of temperature, time and addition of NaOH and H(2)O(2) were statistically evaluated for methane production. Explosive pretreatment was more successful than the nonexplosive method, and gave the best results at 220 degrees C, 10 min, with addition of both 2% NaOH and 2% H(2)O(2). Digestion of the pretreated materials at these conditions yielded 493 N ml/g VS methane which was 107% more than the untreated materials. In addition, the initial digestion rate was improved by 132% compared to the untreated samples. The addition of NaOH was, besides the explosion effect, the most important factor to improve the biogas production.

  1. Hazard Analysis for the Pretreatment Engineering Platform (PEP)

    Energy Technology Data Exchange (ETDEWEB)

    Sullivan, Robin S.; Geeting, John GH; Lawrence, Wesley E.; Young, Jonathan

    2008-07-10

    The Pretreatment Engineering Platform (PEP) is designed to perform a demonstration on an engineering scale to confirm the Hanford Waste Treatment Plant Pretreatment Facility (PTF) leaching and filtration process equipment design and sludge treatment process. The system will use scaled prototypic equipment to demonstrate sludge water wash, caustic leaching, oxidative leaching, and filtration. Unit operations to be tested include pumping, solids washing, chemical reagent addition and blending, heating, cooling, leaching, filtration, and filter cleaning. In addition, the PEP will evaluate potential design changes to the ultrafiltration process system equipment to potentially enhance leaching and filtration performance as well as overall pretreatment throughput. The skid-mounted system will be installed and operated in the Processing Development Laboratory-West at Pacific Northwest National Laboratory (PNNL) in Richland, Washington.

  2. Pretreatment strategies for delignification of sugarcane bagasse: a review

    Directory of Open Access Journals (Sweden)

    Susan Grace Karp

    2013-08-01

    Full Text Available The valorization of agro-residues by biological routes is a key technology that contributes to the development of sustainable processes and the generation of value-added products. Sugarcane bagasse is an agro-residue generated by the sugar and alcohol industry in Brazil (186 million tons per year, composed essentially of cellulose (32-44%, hemicellulose (27-32% and lignin (19-24%. The conversion of sugarcane bagasse into fermentable sugars requires essentially two steps: pretreatment and hydrolysis. The aim of the pretreatment is to separate the lignin and break the structure of lignocellulose, and it is one of the most critical steps in the process of converting biomass to fermentable sugars. The aim of this review is to describe different pretreatment strategies to promote the delignification of the sugarcane bagasse by thermo-chemical and biological processes.

  3. Chemical and Physicochemical Pretreatment of Lignocellulosic Biomass: A Review

    Directory of Open Access Journals (Sweden)

    Gary Brodeur

    2011-01-01

    Full Text Available Overcoming the recalcitrance (resistance of plant cell walls to deconstruction of lignocellulosic biomass is a key step in the production of fuels and chemicals. The recalcitrance is due to the highly crystalline structure of cellulose which is embedded in a matrix of polymers-lignin and hemicellulose. The main goal of pretreatment is to overcome this recalcitrance, to separate the cellulose from the matrix polymers, and to make it more accessible for enzymatic hydrolysis. Reports have shown that pretreatment can improve sugar yields to higher than 90% theoretical yield for biomass such as wood, grasses, and corn. This paper reviews different leading pretreatment technologies along with their latest developments and highlights their advantages and disadvantages with respect to subsequent hydrolysis and fermentation. The effects of different technologies on the components of biomass (cellulose, hemicellulose, and lignin are also reviewed with a focus on how the treatment greatly enhances enzymatic cellulose digestibility.

  4. Urine pretreatment for waste water processing systems. [for space station

    Science.gov (United States)

    Winkler, H. E.; Verostko, C. E.; Dehner, G. F.

    1983-01-01

    Recovery of high quality water from urine is an essential part of life support on a Space Station to avoid costly launch and resupply penalties. Water can be effectively recovered from urine by distillation following pretreatment by a chemical agent to inhibit microorganism contamination and fix volatile ammonia constituents. This paper presents the results of laboratory investigations of several pretreatment chemicals which were tested at several concentration levels in combination with sulfuric acid in urine. The optimum pretreatment formulation was then evaluated with urine in the Hamilton Standard Thermoelectric Integrated Membrane Evaporation Subsystem (TIMES). Over 2600 hours of test time was accumulated. Results of these laboratory and system tests are presented in this paper.

  5. Fluid mechanics relevant to flow through pretreatment of cellulosic biomass.

    Science.gov (United States)

    Archambault-Léger, Véronique; Lynd, Lee R

    2014-04-01

    The present study investigates fluid mechanical properties of cellulosic feedstocks relevant to flow through (FT) pretreatment for biological conversion of cellulosic biomass. The results inform identifying conditions for which FT pretreatment can be implemented in a practical context. Measurements of pressure drop across packed beds, viscous compaction and water absorption are reported for milled and not milled sugarcane bagasse, switchgrass and poplar, and important factors impacting viscous flow are deduced. Using biomass knife-milled to pass through a 2mm sieve, the observed pressure drop was highest for bagasse, intermediate for switchgrass and lowest for poplar. The highest pressure drop was associated with the presence of more fine particles, greater viscous compaction and the degree of water absorption. Using bagasse without particle size reduction, the instability of the reactor during pretreatment above 140kg/m(3) sets an upper bound on the allowable concentration for continuous stable flow.

  6. Pretreatment of woody biomass for biofuel production: energy efficiency, technologies, and recalcitrance.

    Science.gov (United States)

    Zhu, J Y; Pan, Xuejun; Zalesny, Ronald S

    2010-07-01

    This mini review discusses several key technical issues associated with cellulosic ethanol production from woody biomass: energy consumption for woody biomass pretreatment, pretreatment energy efficiency, woody biomass pretreatment technologies, and quantification of woody biomass recalcitrance. Both total sugar yield and pretreatment energy efficiency, defined as the total sugar recovery divided by total energy consumption for pretreatment, should be used to evaluate the performance of a pretreatment process. A post-chemical pretreatment wood size-reduction approach was proposed to significantly reduce energy consumption. The review also emphasizes using a low liquid-to-wood ratio (L/W) to reduce thermal energy consumption for any thermochemical/physical pretreatment in addition to reducing pretreatment temperature.

  7. Pretreatment of food waste with high voltage pulse discharge towards methane production enhancement.

    Science.gov (United States)

    Zou, Lianpei; Ma, Chaonan; Liu, Jianyong; Li, Mingfei; Ye, Min; Qian, Guangren

    2016-12-01

    Anaerobic batch tests were performed to investigate the methane production enhancement and solid transformation rates from food waste (FW) by high voltage pulse discharge (HVPD) pretreatment. The total cumulative methane production with HVPD pretreatment was 134% higher than that of the control. The final volatile solids transformation rates of FW with and without HVPD pretreatment were 54.3% and 32.3%, respectively. Comparison study on HVPD pretreatment with acid, alkali and ultrasonic pretreatments showed that the methane production and COD removal rates of FW pretreated with HVPD were more than 100% higher than the control, but only about 50% higher can be obtained with other pretreatments. HVPD pretreatment could be a promising pretreatment method in the application of energy recovery from FW.

  8. Peracetic acid-ionic liquid pretreatment to enhance enzymatic saccharification of lignocellulosic biomass.

    Science.gov (United States)

    Uju; Abe, Kojiro; Uemura, Nobuyuki; Oshima, Toyoji; Goto, Masahiro; Kamiya, Noriho

    2013-06-01

    To enhance enzymatic saccharification of pine biomass, the pretreatment reagents peracetic acid (PAA) and ionic liquid (IL) were validated in single reagent pretreatments or combination pretreatments with different sequences. In a 1h saccharification, 5-25% cellulose conversion was obtained from the single pretreatment of PAA or IL. In contrast, a marked enhancement in conversion rates was achieved by PAA-IL combination pretreatments (45-70%). The PAA followed by IL (PAA+IL) pretreatment sequence was the most effective for preparing an enzymatic digestible regenerated biomass with 250-fold higher glucose formation rates than untreated biomass and 2- to 12-fold higher than single pretreatments with PAA or IL alone. Structural analysis confirmed that this pretreatment resulted in biomass with highly porous structural fibers associated with the reduction of lignin content and acetyl groups. Using the PAA+IL sequence, biomass loading in the pretreatment step can be increased from 5% to 15% without significant decrease in cellulose conversion.

  9. Fungal pretreatment of straw for enhanced biogas yield

    Energy Technology Data Exchange (ETDEWEB)

    Feng, Xinmei; Pilar Castillo, Maria del; Schnuerer, Anna

    2013-07-01

    Among lignocellulosic materials from the agricultural sector, straw is considered to have the biggest potential as a biofuel and therefore also represents a big potential for biogas production. However, the degradation of lignocellulosic materials is somewhat restricted due to the high content of lignin that binds cellulose and hemicellulose and makes them unavailable for microbial degradation. Consequently, low methane yields are achieved. The biodegradability of the lignocellulosic material can be increased by a pretreatment. Optimally the pre-treatment should give an increase in the formation of sugars while avoiding the degradation or loss of carbohydrates and the formation of inhibitory by-products. The treatment should also be cost-effective. Different methods for pre-treatment of lignocellulosic material have been explored, for example thermal, acid, alkaline and oxidative pretreatments. However, they often have a high energy demand. Biological treatment with fungi represents an alternative method for pretreatment of lignocellulosic materials that could be comparably more environmentally friendly, easier to operate and with low energy input. The fungal groups of interest for lignocellulose degradation are the wood decaying fungi, such as the white-, brown-rot and cellulose degraders. The purpose with this work was to increase the biogas potential of straw by using a pretreatment with fungi. Straw was incubated with fungi at aerobic conditions under certain periods of time. The growth and colonization of the straw by the fungi was expected to increase the availability of the lignocellulosic structure of the straw and thus positively affect the biogas potential. In addition also, the spent lignocellulosic material from the cultivation of edible fungi was investigated. We hypothesized that also growth of edible fungi could give a more accessible material and thus give higher biogas potential compared to the substrate before fungal growth.

  10. Bioethanol production: Pretreatment and enzymatic hydrolysis of softwood

    Energy Technology Data Exchange (ETDEWEB)

    Tengborg, Charlotte

    2000-05-01

    The enzymatic hydrolysis process can be used to produce bioethanol from softwood, which are the dominating raw material in the Northern hemisphere. This thesis deals with the development of the process focusing on the pretreatment and the enzymatic hydrolysis stages. The influence of pretreatment conditions on sugar yield, and the effect of inhibitors on the ethanol yield, were investigated for spruce and pine. The maximum yields of hemicellulose sugars and glucose were obtained under different pretreatment conditions. This indicates that two-stage pretreatment may be preferable. The added catalysts, H{sub 2}SO{sub 4} and SO{sub 2}, resulted in similar total sugar yields about 40 g/100 g dry raw material. However, the fermentability of SO{sub 2}-impregnated material was better. This pretreatment resulted in the formation of inhibitors to the subsequent process steps, e.g. sugar and lignin degradation products. The glucose yield in the enzymatic hydrolysis stage was affected by various parameters such as enzyme loading, temperature, pH, residence time, substrate concentration, and agitation. To decrease the amount of fresh water used and thereby waste water produced, the sugar-rich prehydrolysate from the pretreatment step was included in the enzymatic hydrolysis of the solid fraction, resulting in a reduction in the cellulose conversion of up to 36%. Different prehydrolysate detoxification methods, such as treatment with Ca(OH){sub 2}, laccase, and fermentation using yeast, were investigated. The latter was shown to be very efficient. The amount of fresh water used can be further reduced by recycling various process streams. This was simulated experimentally in a bench-scale process. A reduction in fresh water demand of 50% was obtained without any further negative effects on either hydrolysis or fermentation.

  11. Pre-treating Seed to Enhance Germination of Desert Shrubs

    Energy Technology Data Exchange (ETDEWEB)

    W. K. Ostler; D. C. Anderson; D. J. Hansen

    2002-06-01

    Creosotebush [Larrea tridentata (D.C.) Cav.] and white bursage [Ambrosia dumosa (A. Gray) W.W. Payne] seeds were subjected to pre-treatments of rinsing and soaking in water and thiourea to enhance germination in laboratory experiments. The effects of darkness, temperature, seed source, and soil moisture were also evaluated in the laboratory. The best pre-treatment from the laboratory experiments, rinsing with water for 36 hours followed by drying, was field-tested at Fort Irwin, California. Two sites and two seeding dates (early March and mid April) were determined for each site. Five mulch treatments (no mulch, straw, gravel, chemical stabilizer, and plastic) were evaluated in combination with the seed pre-treatments. Field emergence was greatly enhanced with the seed pre-treatment for white bursage during the March (18-42% increase in germination) and April seedings (16-23% increase in germination). Creosotebush showed poor germination during March (2-5%) when soil temperatures averaged 15 C, but germination increased during the April trials (6-43%) when soil temperatures averaged 23 C. The seed pre-treatment during the April trials increased germination from 16-23%. The plastic mulch treatment increased germination dramatically during both the March and April trials. The plastic mulch increased soil temperatures (8-10 C)and maintained high humidity during germination. Both the chemical stabilizer and the gravel mulches improved germination over the control while the straw mulch decreased germination. These results suggest that seed pre-treatments combined with irrigation and mulch are effective techniques to establish these two dominant Mojave Desert species from seed.

  12. Membrane damage by bile salts: the protective function of phospholipids.

    Science.gov (United States)

    Martin, G P; Marriott, C

    1981-12-01

    The direct toxicity of sodium deoxycholate (SDC) and lysophosphatidylcholine (LPC) to biological membranes was assessed by measurement of goldfish overturn time. When phosphatidylcholine (PC) was incorporated into the aqueous media, the toxicity of both SDC and LPC was reduced, as indicated by increased overturn time. Fish were also pretreated for various times in media containing (a) 1 mM SDC and (b) 1 mM SDC with 1 mM PC. Subsequent transfer to solution, 100 mg litre-1 quinalbarbitone sodium showed that reciprocal overturn times for fish treated using method (a) increased linearly with duration of pretreatment up to a limiting value, obtained after 20 min exposure; 40 min exposure to 1 mM SDC was directly toxic. Fish pretreated using regimen (b) survived longer when challenged with barbiturate, and the reciprocal overturn times were a linear function of time of pretreatment up to at least 40 min. PC also provided protection against membrane damage caused by the synthetic surfactant sodium dodecyl sulphate. Mixed micelle formation between PC and surfactant is thought to account for the protective effects. The results are of significance in the consideration of reflux hypothesis for the aetiology of gastric ulceration and also the possible formulation of drug delivery systems intended to enhance absorption whilst minimizing gastrointestinal damage.

  13. GSDO Program Hexavalent Chrome Alternatives: Final Pretreatments Test Report

    Science.gov (United States)

    Kessel, Kurt

    2013-01-01

    Hexavalent chrome free pretreatments should be considered for use on Ground Support Equipment (OSE) and Electrical Ground Support Equipment (EOSE). Both of the hexavalent chrome free pretreatments (Metalast TCP HF and SurTec 650C) evaluated by this project met, and in some instances exceeded, the requirements ofMIL-DTL-5541 "Chemical Conversion Coatings on Aluminum and Aluminum Alloys". For DC resistance measurements, both Metalast TCP HF and SurTec (!50C met initial requirements following assembly and in many cases continued to maintain passing readings for the duration of testing.

  14. Effect of Surface Pretreatment on Adhesive Properties of Aluminum Alloys

    Institute of Scientific and Technical Information of China (English)

    Jinsheng ZHANG; Xuhui ZHAO; Yu ZUO; Jinping XIONG; Xiaofeng ZHANG

    2008-01-01

    The lap-shear strength and durability of adhesive bonded AI alloy joints with different pretreatments were studied by the lap-shear test and wedge test. The results indicate that the maximum lap-shear strength and durability of the bonding joints pretreated by different processes are influenced by the grade of abrasive papers and can be obviously improved by phosphoric acid anodizing. Alkali etching can obviously improve the durability of bonding joints although it slightly influences the maximum lap-shear strength. The process which is composed of grit-finishing, acetone degreasing, alkali etching and phosphoric acid anodizing, provides a better adhesive bonding property of AI alloy.

  15. Protective Coatings

    Science.gov (United States)

    1980-01-01

    General Magnaplate Corporation's pharmaceutical machine is used in the industry for high speed pressing of pills and capsules. Machine is automatic system for molding glycerine suppositories. These machines are typical of many types of drug production and packaging equipment whose metal parts are treated with space spinoff coatings that promote general machine efficiency and contribute to compliance with stringent federal sanitation codes for pharmaceutical manufacture. Collectively known as "synergistic" coatings, these dry lubricants are bonded to a variety of metals to form an extremely hard slippery surface with long lasting self lubrication. The coatings offer multiple advantages; they cannot chip, peel or be rubbed off. They protect machine parts from corrosion and wear longer, lowering maintenance cost and reduce undesired heat caused by power-robbing friction.

  16. Offspring Protection

    Directory of Open Access Journals (Sweden)

    Eric T. Steiner

    2016-08-01

    Full Text Available Parental aggression, that is, offspring protection aggression, can be viewed as a type of parental investment. Most mammalian males do not exhibit parental investment and therefore exhibit little, if any, parental aggression. Men demonstrate parental investment, and are typically more physically aggressive than women, but parental physical aggression in humans has been largely unexplored. The current study examined potential sex differences in estimates of parental physical aggression involving hypothetical situations, while controlling for general physical aggression. A self-report measure was administered to 217 students from a western U.S. university (55 male nonparents, 50 female nonparents, 54 fathers, and 58 mothers. Male nonparents reported higher parental physical aggression than female nonparents, but there was no difference between mothers and fathers. The results are interpreted in light of ancestral effects of sexual selection and proximal effects of sex differences in testosterone, risk taking, and fear aversion.

  17. An assessment of acid wash and bioleaching pre-treating options to remove mercury from coal

    Energy Technology Data Exchange (ETDEWEB)

    Laura C. Dronen; April E. Moore; Evguenii I. Kozliak; Wayne S. Seames [University of North Dakota, Grand Forks, ND (USA). Department of Chemical Engineering

    2004-01-01

    The United States Environmental Protection Agency is expected to begin regulating the release of vapor-phase mercury from coal-fired power plants in the year 2007. Chemical pre-treatment methods were investigated for mercury removal effectiveness from pulverized low-sulfur North Dakota lignite coal. More limited results were obtained for a pulverized high-sulfur Blacksville bituminous coal. A two-step acid wash treatment showed removal rates of 60 90%, compared to one-step treatments with concentrated HCl, which yielded removals of 30 38%. Removal effectiveness is similar for first step solvents of water, pH 5.0 acid, or pH 2.0 acid followed by concentrated HCl as the second step solvent, and is independent of first step incubation time. Neither of two bacterial strains, Thiobacillus ferrooxidans and T. thiooxidans, was found effective for mercury removal. 23 refs., 5 tabs.

  18. A new magnesium bisulfite pretreatment (MBSP) development for bio-ethanol production from corn stover.

    Science.gov (United States)

    Yu, Heng; Ren, Jiwei; Liu, Lei; Zheng, Zhaojuan; Zhu, Junjun; Yong, Qiang; Ouyang, Jia

    2016-01-01

    This study established a new more neutral magnesium bisulfate pretreatment (MBSP) using magnesium bisulfate as sulfonating agent for improving the enzymatic hydrolysis efficiency of corn stover. Using the MBSP with 5.21% magnesium bisulfate, 170°C and pH 5.2 for 60 min, about 90% of lignin and 80% of hemicellulose were removed from biomass and more than 90% cellulose conversion of substrate was achieved after 48 h hydrolysis. About 6.19 kg raw corn stover could produce 1 kg ethanol by Saccharomyces cerevisiae. Meanwhile, MBSP also could protect sugars from excessive degradation, prevent fermentation inhibition formation and directly convert the hemicelluloses into xylooligosaccharides as higher-value products. These results suggested that the MBSP method offers an alternative approach to the efficient conversion of nonwoody lignocellulosic biomass to ethanol and had broad space for development.

  19. Fungal cellulase/xylanase production and corresponding hydrolysis using pretreated corn stover as substrates.

    Science.gov (United States)

    Zhang, Liang; Wang, Xiaoqing; Ruan, Zhenhua; Liu, Ying; Niu, Xiaorui; Yue, Zhengbo; Li, Zhimin; Liao, Wei; Liu, Yan

    2014-01-01

    Three pretreated corn stover (ammonia fiber expansion, dilute acid, and dilute alkali) were used as carbon source to culture Trichoderma reesei Rut C-30 for cellulase and xylanase production. The results indicated that the cultures on ammonia fiber expansion and alkali pretreated corn stover had better enzyme production than the acid pretreated ones. The consequent enzymatic hydrolysis was performed applying fungal enzymes on pretreated corn stover samples. Tukey's statistical comparisons exhibited that there were significant differences on enzymatic hydrolysis among different combination of fungal enzymes and pretreated corn stover. The higher sugar yields were achieved by the enzymatic hydrolysis of dilute alkali pretreated corn stover.

  20. Methods of pretreating comminuted cellulosic material with carbonate-containing solutions

    Science.gov (United States)

    Francis, Raymond

    2012-11-06

    Methods of pretreating comminuted cellulosic material with an acidic solution and then a carbonate-containing solution to produce a pretreated cellulosic material are provided. The pretreated material may then be further treated in a pulping process, for example, a soda-anthraquinone pulping process, to produce a cellulose pulp. The pretreatment solutions may be extracted from the pretreated cellulose material and selectively re-used, for example, with acid or alkali addition, for the pretreatment solutions. The resulting cellulose pulp is characterized by having reduced lignin content and increased yield compared to prior art treatment processes.

  1. Thermochemical pretreatment of lignocellulose to enhance methane fermentation: II. Evaluation and application of pretreatment model.

    Science.gov (United States)

    Baugh, K D; Levy, J A; McCarty, P L

    1988-01-01

    A model was developed and evaluated as a tool for predicting the formation of soluble products from staged thermochemical treatment of lignocellulosic materials under acidic conditions typical of autohydrolysis. The model was used to predict the general trend of hemi-cellulose and cellulose hydrolysis between pH 2 and 4 and temperatures of 170-230 degrees C, and results were compared with experimental data. When the model was evaluated for this range of temperatures and pH values, results indicated: (1) a relatively low temperature (175 degrees C) during the first stage allows hydrolysis of the hemi-cellulose polysaccharides without significant mono-saccharide decomposition, (2) subsequent stages at higher temperatures (equal or greater than 200 degrees C) are needed for significant cellulose hydrolysis, but glucose decomposition will also occur, and, (3) a pH in the range of 2-2.5 will enhance polysaccharide hydrolysis while limiting monosaccharide decomposition. The model's predictions, indicating that the formation of biodegradable products could be optimized using Pretreatments at pH 2-2.5 for the pH range evaluated, were confirmed in experiments with white fir as a representative lig nocellulose.

  2. Acetone-butanol-ethanol production from corn stover pretreated by alkaline twin-screw extrusion pretreatment.

    Science.gov (United States)

    Zhang, Yuedong; Hou, Tongang; Li, Bin; Liu, Chao; Mu, Xindong; Wang, Haisong

    2014-05-01

    In this study, the alkaline twin-screw extrusion pretreated corn stover was subjected to enzymatic hydrolysis after washing. The impact of solid loading and enzyme dose on enzymatic hydrolysis was investigated. It was found that 68.2 g/L of total fermentable sugar could be obtained after enzymatic hydrolysis with the solid loading of 10 %, while the highest sugar recovery of 91.07 % was achieved when the solid loading was 2 % with the cellulase dose of 24 FPU/g substrate. Subsequently, the hydrolyzate was fermented by Clostridium acetobutylicum ATCC 824. The acetone-butanol-ethanol (ABE) production of the hydrolyzate was compared with the glucose, xylose and simulated hydrolyzate medium which have the same reducing sugar concentration. It was shown that 7.1 g/L butanol and 11.2 g/L ABE could be produced after 72 h fermentation for the hydrolyzate obtained from enzymatic hydrolysis with 6 % solid loading. This is comparable to the glucose and simulated hydrozate medium, and the overall ABE yield could reach 0.112 g/g raw corn stover.

  3. Antipruritic effect of pretreatment with 8% topical capsaicin on histamine- and cowhage-evoked itch in healthy volunteers

    DEFF Research Database (Denmark)

    Andersen, Hjalte Holm; Marker, Jens Broch; Hoeck, Emil A.;

    2017-01-01

    for 24hrs on each volar forearm. After capsaicin/vehicle application, histamine (1%, administered prick test lancets) and cowhage (40-45 spicules) were applied in pretreated areas. Evoked itch and pain intensities were recorded for 10 minutes using a visual analog scale (0-10 cm), while Sensitivity......-histaminergic itch in a standard 1-hour treatment. Further investigations are needed to elucidate the clinical potential of high-concentration capsaicin as an antipruritic. This article is protected by copyright. All rights reserved....

  4. Effects of Ultrasonic and Acid Pretreatment on Food Waste Disintegration and Volatile Fatty Acid Production

    Institute of Scientific and Technical Information of China (English)

    Qinglian Wu; Wanqian Guo∗; Shanshan Yang; Haichao Luo; Simai Peng; Nanqi Ren

    2015-01-01

    This study aims at investigating the effects of ultrasonic and acid pretreatment on food waste ( FW) disintegration and volatile fatty acid ( VFA ) production. Single⁃factor experiments are carried out to obtain optimal conditions of individual ultrasonic and acid pretreatment, and response surface method ( RSM ) is applied to optimize the conditions of the combination of ultrasonic and acid ( UA) pretreatment. Results show that the optimal acid, ultrasonic and UA pretreatments conditions are individual pH 2, individual ultrasonic energy density of 1�0 W/mL and the combination of ultrasonic energy density1�11 W/mL and pH 1�43, respectively. Correspondingly, the maximum disintegration degrees ( DD) of 46�90%, 57�38% and68�83%are obtained by acid, ultrasonic and UA pretreatments, respectively. After optimizing pretreatment conditions, batch experiments are operated to produce VFA from raw and pretreated FW under anaerobic fermentation process. Both the maximum VFA production ( 976�17 mg COD/gVS) and VFA/SCOD ( 72�89%) are obtained with ultrasonic pretreatment, followed by UA pretreatment, non⁃pretreatment and acid pretreatment, respectively. This observation demonstrates that a higher acidity on acid and UA pretreatments inhibits the generation of VFA. Results suggest that ultrasonic pretreatment is preferable to promote the disintegration degree of FW and VFA production.

  5. Effect of moisture on pretreatment efficiency for anaerobic digestion of lignocellulosic substrates.

    Science.gov (United States)

    Peces, M; Astals, S; Mata-Alvarez, J

    2015-12-01

    The present study evaluates the effect of moisture in low-temperature and ultrasound pretreatment on lignocellulosic substrates anaerobic biodegradability, where brewer's spent grain was used as model substrate. Besides moisture content, low-temperature pretreatment was also evaluated in terms of temperature (60-80°C) and exposure time (12-72 h). Likewise, ultrasonication was also evaluated in terms of specific energy (1000-50,000 kJ kg TS(-1)). In addition, the effect of substrate particle size reduction by milling pretreatment was also considered. The results clearly demonstrated that substrate moisture (total solid concentration) is a significant parameter for pretreatment performance, although it has been rarely considered in pretreatment optimisation. Specifically, moisture optimisation increased the methane yield of brewer's spent grain by 6% for low-temperature pretreatment (60°C), and by 14% for ultrasound pretreatment (1000 kJ kg TS(-1)) towards the control (without pretreatment). In both pretreatments, the experimental optimum total solid concentration was 100 gTS kg(-1). Thus, lowering substrate moisture, a strategy suggested attaining energetic pretreatment feasibility, needs to be analysed as another pretreatment variable since it might have limited correlation. Finally, a preliminary energetic balance of the pretreatments under study showed that the extra methane production could not cover the energetic pretreatment expenses.

  6. Bromine pretreated chitosan for adsorption of lead (II) from water

    Indian Academy of Sciences (India)

    Rajendra Dongre; Minakshi Thakur; Dinesh Ghugal; Jostna Meshram

    2012-10-01

    Pollution by heavy metals like lead (II) is responsible for health hazards and environmental degradation. Adsorption is a prevalent method applied for removal of heavy metal pollutants from water. This study explored adsorption performances of 30% bromine pretreated chitosan for lead (II) abatement from water. Bromine pretreatment alters porosity and specific surface area of chitosan by means of physicochemical interaction with cationic sites of chitosan skeleton, besides imparting anionic alteration at amino linkages of chitosan, to remove lead (II) by chemical interactions on superfluous active sites as characterized by FTIR, SEM, DTA and elemental analysis. Lead adsorptions were studied in batch mode by varying parameters viz. pH, bromine loading, sorbent dosage, initial lead concentration, contact time and temperature. The adsorption equilibrium data was well fitted to Freundlich isotherm and maximum sorption capacity of 30% bromine pretreated chitosan sorbent was 1.755 g/kg with 85–90% lead removal efficiency. Though cost and applicability of sorbent is unproven, yet contrast to raw chitosan derivatives, activated carbons and some resins, 30% bromine pretreated chitosan endow benign and efficient lead abatement technique.

  7. Ethanol production from steam-explosion pretreated wheat straw.

    Science.gov (United States)

    Ballesteros, Ignacio; Negro, Ma José; Oliva, José Miguel; Cabañas, Araceli; Manzanares, Paloma; Ballesteros, Mercedes

    2006-01-01

    Bioconversion of cereal straw to bioethanol is becoming an attractive alternative to conventional fuel ethanol production from grains. In this work, the best operational conditions for steam-explosion pretreatment of wheat straw for ethanol production by a simultaneous saccharification and fermentation process were studied, using diluted acid [H2SO4 0.9% (w/w)] and water as preimpregnation agents. Acid- or water-impregnated biomass was steam-exploded at different temperatures (160-200 degrees C) and residence times (5, 10, and 20 min). Composition of solid and filtrate obtained after pretreatment, enzymatic digestibility and ethanol production of pretreated wheat straw at different experimental conditions was analyzed. The best pretreatment conditions to obtain high conversion yield to ethanol (approx 80% of theoretical) of cellulose-rich residue after steam-explosion were 190 degrees C and 10 min or 200 degrees C and 5 min, in acid-impregnated straw. However, 180 degrees C for 10 min in acid-impregnated biomass provided the highest ethanol yield referred to raw material (140 L/t wheat straw), and sugars recovery yield in the filtrate (300 g/kg wheat straw).

  8. Pretreatments to enhance the digestibility of lignocellulosic biomass

    NARCIS (Netherlands)

    Hendriks, A.T.W.M.; Zeeman, G.

    2009-01-01

    Lignocellulosic biomass represents a rather unused source for biogas and ethanol production. Many factors, like lignin content, crystallinity of cellulose, and particle size, limit the digestibility of the hemicellulose and cellulose present in the lignocellulosic biomass. Pretreatments have as a go

  9. Plasma-Assisted Pretreatment of Wheat Straw for Ethanol Production

    DEFF Research Database (Denmark)

    Schultz-Jensen, Nadja; Kádár, Zsófia; Thomsen, Anne Belinda;

    2011-01-01

    carboxylic acids and phenolic compounds were found, e.g., vanillic acid, acetic acid, and formic acid. Some components had the highest concentration at the beginning of the ozonisation process (0.5, 1 h), e.g., 4-hydroxybenzladehyde, while the concentration of others increased during the entire pretreatment...

  10. Influence of surface pretreatment of fiber posts on cement delamination

    NARCIS (Netherlands)

    Jongsma, L.A.; Kleverlaan, C.J.; Feilzer, A.J.

    2010-01-01

    Objectives To evaluate the influence of post surface pretreatment on the delamination strength of different cements from a prefabricated FRC post tested in a three-point bending test. Methods Three cements were tested; RelyX Unicem, DC Core Automix, and Panavia F2.0. Per cement, 40 posts (D.T. Light

  11. Fast pyrolysis of biomass thermally pretreated by torrefaction

    Science.gov (United States)

    Torrefied biomass samples were produced from hardwood and switchgrass pellets using the biochar experimenter’s kit (BEK) reactor and analyzed for their utility as pretreated feedstock for biofuels production via fast pyrolysis. The energy efficiency for the BEK torrefaction process with propane gas ...

  12. Separations/pretreatment considerations for Hanford privatization phase 2

    Energy Technology Data Exchange (ETDEWEB)

    Hunt, R.D.; McGinnis, C.P.; Welch, T.D.

    1998-05-01

    The Tank Focus Area is funded to develop, demonstrate, and deploy technologies that will assist in the treatment and closure of its nuclear waste tanks. Pretreatment technologies developed to support the privatization effort by the Department of Energy are reviewed. Advancements in evaporation, solid-liquid separation, sludge treatment, solids controls, sodium management, and radionuclide removal are considered.

  13. 40 CFR 417.166 - Pretreatment standards for new sources.

    Science.gov (United States)

    2010-07-01

    ... subpart that introduces process wastewater pollutants into a publicly owned treatment works must comply... publicly owned treatment works by a new source subject to the provisions of this subpart. (a) There shall... pollutant property Pretreatment standard BOD5 No limitation. COD Do. TSS Do. Surfactants Do. Oil and...

  14. Low-liquid pretreatment of corn stover with aqueous ammonia.

    Science.gov (United States)

    Li, Xuan; Kim, Tae Hyun

    2011-04-01

    A low-liquid pretreatment method of corn stover using aqueous ammonia was studied to reduce the severity and liquid throughput associated with the pretreatment step for ethanol production. Corn stover was treated at 0.5-50.0 wt.% of ammonia loading, 1:0.2-5.0 (w/w) of solid-to-liquid ratio, 30 °C for 4-12 weeks. The effects of these conditions on the composition and enzyme digestibility of pretreated corn stover were investigated. Pretreatment of corn stover at 30°C for four weeks using 50 wt.% of ammonia loading and 1:5 solid-to-liquid ratio resulted in 55% delignification and 86.5% glucan digestibility with 15 FPU cellulase+30 CBU β-glucosidase/g-glucan. Simultaneous saccharification and fermentation of corn stover treated at 30 °C for four weeks using 50 wt.% ammonia loading and 1:2 solid-to-liquid ratio gave an ethanol yield of 73% of the theoretical maximum based on total carbohydrates (glucan+xylan) present in the untreated material.

  15. Optimization of Fenton pretreatment for 2-chlorophenol solution

    Institute of Scientific and Technical Information of China (English)

    贺仲兵; 刘云国; 肖玉

    2013-01-01

    Fenton oxidation was used as the pretreatment of 2-chlorophenol wastewater with the objective of dechlorination, as it was considered that after breakage of aryl—Cl bond, the generated intermediates may be easily biodegraded. Hence, the optimization of pH and the low Fenton reagent doses for dechlorination was investigated. More than 99% dechlorination is obtained at the optimal pH 4 and the Fenton reagent doses of 86 mmol/L H2 O2 and 2.87 mmol/L Fe2+. The corresponding 2-chlorophenol is degraded completely, 80.02% COD is also removed, and the biodegradability, evaluated in terms of the BOD5 /COD ratio, is increased up to 0.41. To test the effect of this pretreatment, the pretreated 2-chlorophenol wastewater was fed to a sequencing batch reactor(SBR). The results show that complete mineralization is achieved. It is demonstrated that, for the treatment of recalcitrant compounds like 2-chlorophenol, the Fenton pretreatment could be quite effective and economical for enhancing the biodegradability in a Fenton-biological coupled system.

  16. 40 CFR 421.115 - Pretreatment standards for existing sources.

    Science.gov (United States)

    2010-07-01

    ...,322.000 (i) Subpart K—Reduction of Tantalum Salt to Metal Wet Air Pollution Control. PSES Pollutant or...-Tantalum Subcategory § 421.115 Pretreatment standards for existing sources. Except as provided in 40 CFR... standards for existing sources. The mass of wastewater pollutants in primary columbium-tantalum...

  17. Fuel ethanol production from alkaline peroxide pretreated corn stover

    Science.gov (United States)

    Corn stover (CS) has the potential to serve as an abundant low-cost feedstock for production of fuel ethanol. Due to heterogeneous complexity and recalcitrance of lignocellulosic feedstocks, pretreatment is required to break the lignin seal and/or disrupt the structure of crystalline cellulose to in...

  18. Pretreatment of lignocellulose with biological acid recycling (the Biosulfurol process)

    NARCIS (Netherlands)

    Groenestijn, van J.; Hazewinkel, O.; Bakker, R.R.C.

    2006-01-01

    A biomass pretreatment process is being developed based on contacting lignocellulosic biomass with 70% sulfuric acid and subsequent hydrolysis by adding water. In this process, the hydrolysate can be fermented yielding ethanol, while the sulfuric acid is partly recovered by anion-selective membranes

  19. Gadolinium chloride pretreatment ameliorates acute cadmium-induced hepatotoxicity.

    Science.gov (United States)

    Kyriakou, Loukas G; Tzirogiannis, Konstantinos N; Demonakou, Maria D; Kourentzi, Kalliopi T; Mykoniatis, Michael G; Panoutsopoulos, Georgios I

    2013-08-01

    Cadmium is a known industrial and environmental pollutant. It causes hepatotoxicity upon acute administration. Features of cadmium-induced acute hepatoxicity encompass necrosis, apoptosis, peliosis and inflammatory infiltration. Gadolinium chloride (GdCl3) may prevent cadmium-induced hepatotoxicity by suppressing Kupffer cells. The effect of GdCl3 pretreatment on a model of acute cadmium-induced liver injury was investigated. Male Wistar rats 4-5 months old were injected intraperitoneally with normal saline followed by cadmium chloride (CdCl2; 6.5 mg/kg) or GdCl3 (10 mg/kg) followed by CdCl2 (6.5 mg/kg; groups I and II, respectively). Rats of both the groups were killed at 9, 12, 16, 24, 48 and 60 h after cadmium intoxication. Liver sections were analyzed for necrosis, apoptosis, peliosis and mitoses. Liver regeneration was also evaluated by tritiated thymidine incorporation into hepatic DNA. Serum levels of aspartate aminotransferase (AST) and alanine aminotransferase (ALT) were also determined. Hepatic necrosis, hepatocyte and nonparenchymal cell apoptosis and macroscopic and microscopic types of peliosis hepatis were minimized by gadolinium pretreatment. Serum levels of AST and ALT were also greatly diminished in rats of group II. Tritiated thymidine incorporation into hepatic DNA was increased in gadolinium pretreatment rats. Kupffer cell activation was minimal in both the groups of rats. Gadolinium pretreatment attenuates acute cadmium-induced liver injury in young Wistar rats, with mechanisms other than Kupffer cell elimination.

  20. Coumarin pretreatment alleviates salinity stress in wheat seedlings.

    Science.gov (United States)

    Saleh, Ahmed Mahmoud; Madany, M M Y

    2015-03-01

    The potentiality of COU to improve plant tolerance to salinity was investigated. Wheat grains were primed with COU (50 ppm) and then grown under different levels of NaCl (50, 100, 150 mM) for two weeks. COU pretreatment improved the growth of wheat seedling under salinity, relative to COU-untreated seedlings, due to the accumulation of osmolytes such as soluble sugars and proline. Moreover, COU treatment significantly improved K(+)/Na(+) ratio in the shoots of both salt stressed and un-stressed seedlings. However, in the roots, this ratio increased only under non-salinity. In consistent with phenylalanine ammonia lyase (PAL), phenolics and flavonoids were accumulated in COU-pretreated seedlings under the higher doses of salinity, relative to COU-untreated seedlings. COU primed seedlings showed higher content of the coumarin derivative, scopoletin, and salicylic, chlorogenic, syringic, vanillic, gallic and ferulic acids, under both salinity and non-salinity conditions. Salinity stress significantly improved the activity of peroxidase (POD) in COU-pretreated seedlings. However, the effect of COU on the total antioxidant capacity (TAC) was only obtained at the highest dose of NaCl (150 mM). The present results suggest that COU pretreatment could alleviate the adverse effect of salinity on the growth of wheat seedlings through enhancing, at least partly, the osmoregulation process and antioxidant defense system.

  1. Ondansetron Pretreatment Reduces Pain on Injection of Propofol

    Directory of Open Access Journals (Sweden)

    Anahid Maleki

    2012-04-01

    Full Text Available To assess the effectiveness of ondansetron pretreatment in alleviating propofol injection pain, 135 patients were randomly assigned to one of following three groups. Group 1 who received up to 2 mL pretreatment 50 mg tramadol in the saline, group 2 cases who received up to 2 mL pretreatment 4 mg ondansetron in saline, and group 3 who received up to 2 mL solution saline. A 20 gauge cannula was placed into the largest vein on the dorsum of the hand. Tourniquet was closed to the arm above the cannula and inflates to 70 mmHg, and then drug was injected. After 20 seconds, the tourniquet deflated, and propofol 2mg/kg injected over 10 seconds and pain assessment was made. Results: Tramadol and ondansetron significantly reduced the incidence and severity of propofol injection pain more than placebo (P=0.001. The efficacy of ondansetron in alleviating the pain on injection of propofol was no different from tramadol (P=0.330. Ondansetron pretreatment may be used to reduce the incidence of pain on injection of propofol, an advantage added to the useful prevention of postoperative nausea and vomiting.

  2. Anaerobic digestion of yard waste with hydrothermal pretreatment.

    Science.gov (United States)

    Li, Wangliang; Zhang, Guangyi; Zhang, Zhikai; Xu, Guangwen

    2014-03-01

    The digestibility of lignocellulosic biomass is limited by its high content of refractory components. The objective of this study is to investigate hydrothermal pretreatment and its effects on anaerobic digestion of sorted organic waste with submerged fermentation. Hydrothermal pretreatment (HT) was performed prior to anaerobic digestion, and three agents were examined for the HT: hot compressed water, alkaline solution, and acidic solution. The concentrations of glucose and xylose were the highest in the sample pretreated in acidic solution. Compared with that of the untreated sample, the biogas yields from digesting the samples pretreated in alkaline solution, acidic solution, and hot water increased by 364, 107, and 79%, respectively. The decrease of chemical oxygen demand (COD) in liquid phase followed the same order as for the biogas yield. The initial ammonia content of the treated samples followed the order sample treated in acidic solution > sample treated in alkaline solution > sample treated in hot water. The concentrations of volatile fatty acids (VFAs) were low, indicating that the anaerobic digestion process was running at continuously stable conditions.

  3. Fermentative hydrogen production from pretreated biomass: A comparative study

    NARCIS (Netherlands)

    Panagiotopoulos, I.A.; Bakker, R.R.; Budde, M.A.W.; Vrije, de G.J.; Claassen, P.A.M.; Koukios, E.G.

    2009-01-01

    The aim of this work was to evaluate the potential of employing biomass resources from different origin as feedstocks for fermentative hydrogen production. Mild-acid pretreated and hydrolysed barley straw (BS) and corn stalk (CS), hydrolysed barley grains (BG) and corn grains (CG), and sugar beet ex

  4. Thermochemical Pretreatment for Anaerobic Digestion of Sorted Waste

    Science.gov (United States)

    Hao, W.; Hongtao, W.

    2008-02-01

    The effect of alkaline hydrothermal pre-treatment for anaerobic digestion of mechanically-sorted municipal solid waste (MSW) and source-sorted waste was studied. Waste was hydrothermally pre-treated in dilute alkali solution. Hydrolysis product was incubated in 500 ml saline bottle to determine methane potential (MP) under mesospheric anaerobic conditions. Optimum reaction condition obtained in the study is 170 °C at the dose of 4 g NaOH/100 g solid for one hour. Soluble COD was 13936 mg/L and methane yield was 164 ml/g VS for 6 days incubation at optimum conditions. More than 50% biogas increase was achieved over the control, and methane conversion ratio on carbon basis was enhanced to 30.6%. The digestion period was less than 6 days when pre-treatment temperature was above 130 °C. The organic part of sorted waste is mainly constituted of kitchen garbage and leaf. Model kitchen garbage was completely liquidized at 130 °C for one hour and the methane yield was 276 ml/g VS. Addition of alkali enhance hydroxylation rate and methane yield slightly. The biogas potential of leaf could be observed by pre-treatment above 150 °C under alkaline condition.

  5. Protecting Information

    Science.gov (United States)

    Loepp, Susan; Wootters, William K.

    2006-09-01

    For many everyday transmissions, it is essential to protect digital information from noise or eavesdropping. This undergraduate introduction to error correction and cryptography is unique in devoting several chapters to quantum cryptography and quantum computing, thus providing a context in which ideas from mathematics and physics meet. By covering such topics as Shor's quantum factoring algorithm, this text informs the reader about current thinking in quantum information theory and encourages an appreciation of the connections between mathematics and science.Of particular interest are the potential impacts of quantum physics:(i) a quantum computer, if built, could crack our currently used public-key cryptosystems; and (ii) quantum cryptography promises to provide an alternative to these cryptosystems, basing its security on the laws of nature rather than on computational complexity. No prior knowledge of quantum mechanics is assumed, but students should have a basic knowledge of complex numbers, vectors, and matrices. Accessible to readers familiar with matrix algebra, vector spaces and complex numbers First undergraduate text to cover cryptography, error-correction, and quantum computation together Features exercises designed to enhance understanding, including a number of computational problems, available from www.cambridge.org/9780521534765

  6. Autohydrolysis Pretreatment of Lignocellulosic Biomass for Bioethanol Production

    Science.gov (United States)

    Han, Qiang

    Autohydrolysis, a simple and environmental friendly process, has long been studied but often abandoned as a financially viable pretreatment for bioethanol production due to the low yields of fermentable sugars at economic enzyme dosages. The introduction of mechanical refining can generate substantial improvements for autohydrolysis process, making it an attractive pretreatment technology for bioethanol commercialization. In this study, several lignocellulosic biomass including wheat straw, switchgrass, corn stover, waste wheat straw have been subjected to autohydrolysis pretreatment followed by mechanical refining to evaluate the total sugar recovery at affordable enzyme dosages. Encouraging results have been found that using autohydrolysis plus refining strategy, the total sugar recovery of most feedstock can be as high as 76% at 4 FPU/g enzymes dosages. The mechanical refining contributed to the improvement of enzymatic sugar yield by as much as 30%. Three non-woody biomass (sugarcane bagasse, wheat straw, and switchgrass) and three woody biomass (maple, sweet gum, and nitens) have been subjected to autohydrolysis pretreatment to acquire a fundamental understanding of biomass characteristics that affect the autohydrolysis and the following enzymatic hydrolysis. It is of interest to note that the nonwoody biomass went through substantial delignification during autohydrolysis compared to woody biomass due to a significant amount of p-coumaric acid and ferulic acid. It has been found that hardwood which has a higher S/V ratio in the lignin structure tends to have a higher total sugar recovery from autohydrolysis pretreatment. The economics of bioethanol production from autohydrolysis of different feedstocks have been investigated. Regardless of different feedstocks, in the conventional design, producing bioethanol and co-producing steam and power, the minimum ethanol revenues (MER) required to generate a 12% internal rate of return (IRR) are high enough to

  7. Thermochemical pretreatment of underutilized woody biomass for manufacturing wood composites

    Science.gov (United States)

    Pelaez Samaniego, Manuel Raul

    Prescribed fires, one method for reducing hazardous fuel loads from forest lands in the US, are limited by geographical, environmental, and social impacts. Mechanical operations are an alternative type of fuel treatment but these processes are constrained by the difficulty of economically harvesting and/or using large amounts of low-value woody biomass. Adoption and integration of new technologies into existing wood composite facilities offer better utilization of this material. A pretreatment that enables integration of technologies in a typical composite facility will aid with diversification of product portfolio (e.g. wood composites, fuel pellets, liquid fuels, chemicals). Hot water extraction (HWE) is an option for wood pretreatment. This work provides a fundamental understanding of the physicochemical changes to wood resulting from HWE, and how these changes impact processing and performance of composites. Specific objectives were to: 1) review literature on studies related to the manufacture of composites produced with thermally pretreated wood, 2) manufacture wood plastic composites (WPC) and particleboard using HWE wood and evaluate the impacts of pretreatment on product properties, 3) develop an understanding of the effect of HWE on lignin properties, specifically lignin at the cells surface level after migration from cell walls and middle lamella, 4) discern the influence of lignin on the fiber surface on processing WPCs, and, 5) investigate the effect of changing the pretreatment environment (inert gas instead of water) on lignin behavior. Results show that HWE enhances the resistance of both WPCs and particleboard to water with positive or no effect on mechanical properties. Reduction of hemicelluloses and lignin property changes are suggested as the main reasons for enhancing interaction between wood fiber and resins during composite processing. Lignin on the surface of particles after HWE interacts with thermoplastics during WPCs compounding, thus

  8. Biomass Pretreatment using Ionic Liquid and Glycerol Mixtures

    Science.gov (United States)

    Lynam, Joan Goerss

    Lignocellulosic biomass is a renewable, sustainable resource that can replace or supplement fossil fuels use for liquid fuels and chemicals. However, its recalcitrant structure including interwoven cellulose, hemicelluloses, and lignin biomacromolecules is challenging to deconstruct. Pretreating biomass so that it can be converted to useful liquids dominates process economics. Many pretreatment methods exist, but most require hazardous chemicals or processing conditions. Many ionic liquids (ILs), salts molten below 100°C, can be used to deconstruct lignocellulosic biomass and are less hazardous than the volatile organic compounds typically used. While effective, relatively safe, and recyclable, ILs are expensive. To reduce costs, dilution with other safe compounds is desirable, if there is no impact on deconstruction efficiency. Glycerol, a food additive, is inexpensive and becoming even more so since it is a by-product of the burgeoning biodiesel industry. Use of glycerol as an additive or diluent for ILs is extensively evaluated in this work. Rice hulls are an abundant biomass, with over 100 million tons produced per year, but with little practical use. The IL 1-ethyl-3-methylimidazolium formate ([C2mim][O2CH] or EMIM Form) when mixed with an equal amount of glycerol has been shown to be effective in pretreating rice hulls. Ambient pressure, a pretreatment temperature of 110°C, and a reaction time of three hours produced rice hulls that could be enzymatically hydrolyzed to give reasonably good glucose and xylose yields considering the recalcitrance of this silica-armored biomass. The IL [C2mim][O2CH] was also effective when mixed with an equal amount of glycerol to pretreat loblolly pine, a fast-growing softwood. Loblolly pine was pretreated at 140°C for three hours to produce a solid rich in cellulose and hemicelluloses, while a lignin-rich product could be precipitated from the IL. Similar products were obtained from pretreatment with a mixture of 75% 1

  9. Surface pre-treatment for barrier coatings on polyethylene terephthalate

    Science.gov (United States)

    Bahre, H.; Bahroun, K.; Behm, H.; Steves, S.; Awakowicz, P.; Böke, M.; Hopmann, Ch; Winter, J.

    2013-02-01

    Polymers have favourable properties such as light weight, flexibility and transparency. Consequently, this makes them suitable for food packaging, organic light-emitting diodes and flexible solar cells. Nonetheless, raw plastics do not possess sufficient barrier functionality against oxygen and water vapour, which is of paramount importance for most applications. A widespread solution is to deposit thin silicon oxide layers using plasma processes. However, silicon oxide layers do not always fulfil the requirements concerning adhesion and barrier performance when deposited on films. Thus, plasma pre-treatment is often necessary. To analyse the influence of a plasma-based pre-treatment on barrier performance, different plasma pre-treatments on three reactor setups were applied to a very smooth polyethylene terephthalate film before depositing a silicon oxide barrier layer. In this paper, the influence of oxygen and argon plasma pre-treatments towards the barrier performance is discussed examining the chemical and topological change of the film. It was observed that a short one-to-ten-second plasma treatment can reduce the oxygen transmission rate by a factor of five. The surface chemistry and the surface topography change significantly for these short treatment times, leading to an increased surface energy. The surface roughness rises slowly due to the development of small spots in the nanometre range. For very long treatment times, surface roughness of the order of the barrier layer's thickness results in a complete loss of barrier properties. During plasma pre-treatment, the trade-off between surface activation and roughening of the surface has to be carefully considered.

  10. Pretreatment of sugar cane bagasse for enhanced ruminal digestion.

    Science.gov (United States)

    Deschamps, F C; Ramos, L P; Fontana, J D

    1996-01-01

    Crop residues, such as sugar cane bagasse (SCB), have been largely used for cattle feeding. However, the close association that exists among the three major plant cell-wall components, cellulose, hemicellulose, and lignin, limits the efficiency by which ruminants can degrade these materials. Previously, we have shown that pretreatment with 3% (w/w) phosphoric acid, under relatively mild conditions, increased considerably the nutritional value for SCB. However, in this preliminary study, pretreated residues were not washed prior to in situ degradability assays because we wanted to explore the high initial solvability of lowmol-wt substances that were produced during pretreatment. We have now studied the suitability of water-and/or alkali-washed residues to in situ ruminal digestion. Alkali washing increased substrate cellulose content by removing most of the lignin and other residual soluble substances. As a result the ruminal degradability of these cleaner materials had first-order rate constants five times higher than those substrates with higher lignin content (e.g., stem-exploded bagasse). However, alkali washing also increased the time of ruminal lag phase of the cellulosic residue, probably because of hemicellulose and/or lignin removal and to the development of substrates with higher degree of crystallinity. Therefore, longer lag phases appear to be related to low microbial adherence after extensive water and alkali extraction, as Novell as to the slower process of cellulase induction during ruminal growth. The kinetic data on ruminal digestion were shown to be very well adjusted by a nonlinear model. Although pretreatment enhances substrate accessibility, the occurrence of an exceedingly high amount of lignin byproducts within the pretreated material reduces considerably its potential degradability.

  11. Influence of HCl pretreatment on laser diffraction measurements

    Science.gov (United States)

    Schulte, Philipp; Steininger, Florian; Lockot, Gregori; Lehmkuhl, Frank; Stauch, Georg; Protze, Jens; Fischer, Peter

    2014-05-01

    Sample pretreatment methods in grain size (GS) analyses differ and their influence on GS distributions has been subject of controversial discussions. The standard sample preparation usually comprises the disaggregation into single primary particles. The organic binding material is oxidized by hydrogen peroxide (H2O2) and the containing carbonates are dissolved by hydrochloric acid (HCl). However, laser diffraction measurements of calcified sediment sequences or sediments with high contents of organic matter show non-reproducible changes in the GS distribution. To investigate variations of the GS distribution, selected samples from two different sections in different stages of weathering and sedimentary genesis were measured using a Beckman Coulter LS13320 laser particle size analyser. A high-resolution Holocene sandy loess-paleosol sequence, the Suohuduo section on the eastern margin of the Tibetan Plateau, was investigated. The results were compared with a Pleistocene loess sequence from the Lower Rhine Embayment, the Düsseldorf-Grafenberg section. The entire sample set includes samples of siliciclastic, barely weathered material and sediments from paleosols. The paleosols in the Suohudo section are strongly influenced by steppe fires and are rich in organo-mineral associations and pyrogenic carbon. All samples were pretreated with hydrogen peroxide and sodium pyrophosphate. In order to investigate the influence of HCl on the GS distribution, the samples were subsequently prepared with and without the addition of HCl. The results show that the sample preparation has a significant influence on the detected GS distribution. Hence, prior to the measurement of a sample set, the effectiveness of the pretreatment argents HCl and H2O2 should be evaluated. In order to generate a valid GS distribution, the sample pretreatment must be matched to the aim of the study and the composition of the sample. Paleoclimatic and environmental interpretation based on improper GS

  12. Neuroprotective effects of pretreatment with quercetin as assessed by acetylcholinesterase assay and behavioral testing in poloxamer-407 induced hyperlipidemic rats.

    Science.gov (United States)

    Braun, Josiane B S; Ruchel, Jader B; Adefegha, Stephen A; Coelho, Ana Paula V; Trelles, Kelly B; Signor, Cristiane; Rubin, Maribel A; Oliveira, Juliana S; Dornelles, Guilherme L; de Andrade, Cinthia M; Castilhos, Lívia G; Leal, Daniela B R

    2017-04-01

    Hyperlipidemia is a group of disorders characterized by excessive lipids in the bloodstream. It is associated with the incidence of cardiovascular diseases and recognized as the most important factor underlying the occurrence of atherosclerosis. This study was conducted to investigate whether pretreatment with quercetin can protect against possible memory impairment and deterioration of the cholinergic system in hyperlipidemic rats. Animals were divided into ten groups (n=7): saline/control, saline/quercetin 5mg/kg, saline/quercetin 25mg/kg, saline/quercetin 50mg/kg, saline/simvastatin (0.04mg/kg), hyperlipidemia, hyperlipidemia/quercetin 5mg/kg, hyperlipidemia/quercetin 25mg/kg, hyperlipidemia/quercetin 50mg/kg and hyperlipidemia/simvastatin. The animals were pretreated with quercetin by oral gavage for a period of 30days and hyperlipidemia was subsequently induced by intraperitoneal administration of a single dose of 500mg/kg of poloxamer-407. Simvastatin was administered after the induction of hyperlipidemia. The results demonstrated that hyperlipidemic rats had memory impairment compared with the saline control group (P<0.001). However, pretreatment with quercetin and simvastatin treatment attenuated the damage caused by hyperlipidemia compared with the hyperlipidemic group (P<0.05). Acetylcholinesterase (AChE) activity in the cerebral hippocampus was significantly (P<0.001) reduced in the hyperlipidemic group compared with the control saline group. Pretreatment with quercetin and simvastatin treatment in the hyperlipidemic groups significantly (P<0.05) increased AChE activity compared with the hyperlipidemic group. Our results thus suggest that quercetin may prevent memory impairment, alter lipid metabolism, and modulate AChE activity in an experimental model of hyperlipidemia.

  13. Literature review of physical and chemical pretreatment processes for lignocellulosic biomass

    NARCIS (Netherlands)

    Harmsen, P.F.H.; Huijgen, W.; Bermudez, L.; Bakker, R.

    2010-01-01

    Different pretreatment technologies published in public literature are described in terms of the mechanisms involved, advantages and disadvantages, and economic assessment. Pretreatment technologies for lignocellulosic biomass include biological, mechanical, chemical methods and various combinations

  14. Lignocellulose pretreatment severity – relating pH to biomatrix opening

    DEFF Research Database (Denmark)

    Pedersen, Mads; Meyer, Anne S.

    2010-01-01

    different pH values, temperatures, types of catalysts, and holding times. The consequences of the pretreatment on lignocellulosic biomass are described with special emphasis on the chemical alterations of the biomass during pretreatment, especially highlighting the significance of the pretreatment pH. We...... present a new illustration of the pretreatment effects encompassing the differential responses to the pH and temperature. A detailed evaluation of the use of severity factor calculations for pretreatment comparisons signifies that the multiple effects of different pretreatment factors on the subsequent...... the hydrolysis yields (glucose, xylose) and the pretreatment pH, but no correlation with the pretreatment temperature (90–200 °C). A better recognition and understanding of the factors affecting biomatrix opening, and use of more standardized evaluation protocols, will allow for the identification of new...

  15. Comparison of dilute mineral and organic acid pretreatment for enzymatic hydrolysis of wheat straw

    NARCIS (Netherlands)

    Kootstra, A.M.J.; Beeftink, H.H.; Scott, E.L.; Sanders, J.P.M.

    2009-01-01

    The efficiencies of fumaric, maleic, and sulfuric acid in wheat straw pretreatment were compared. As a measure for pretreatment efficiency, enzymatic digestibility of the lignocellulose was determined. Monomeric glucose and xylose concentrations were measured after subsequent enzymatic hydrolysis, a

  16. Pretreating wheat straw by the concentrated phosphoric acid plus hydrogen peroxide (PHP): Investigations on pretreatment conditions and structure changes.

    Science.gov (United States)

    Wang, Qing; Hu, Jinguang; Shen, Fei; Mei, Zili; Yang, Gang; Zhang, Yanzong; Hu, Yaodong; Zhang, Jing; Deng, Shihuai

    2016-01-01

    Wheat straw was pretreated by PHP (the concentrated H3PO4 plus H2O2) to clarify effects of temperature, time and H3PO4 proportion on hemicellulose removal, delignification, cellulose recovery and enzymatic digestibility. Overall, hemicellulose removal was intensified by PHP comparing to the concentrated H3PO4. Moreover, efficient delignification specially happened in PHP pretreatment. Hemicellulose removal and delignification by PHP positively responded to temperature and time. Increasing H3PO4 proportion in PHP can promote hemicellulose removal, however, decrease the delignification. Maximum hemicellulose removal and delignification were achieved at 100% and 83.7% by PHP. Enzymatic digestibility of PHP-pretreated wheat straw was greatly improved by increasing temperature, time and H3PO4 proportion, and complete hydrolysis can be achieved consequently. As temperature of 30-40°C, time of 2.0 h and H3PO4 proportion of 60% were employed, more than 92% cellulose was retained in the pretreated wheat straw, and 29.1-32.6g glucose can be harvested from 100g wheat straw.

  17. Impact of Alkali Pretreatment on the Chemical Component Distribution and Ultrastructure of Poplar Cell Walls

    OpenAIRE

    Zhe Ji; Zhe Ling; Xun Zhang; Gui-Hua Yang; Feng Xu

    2014-01-01

    Alkali pretreatment is one of the leading pretreatment technologies for biofuel applications. The histochemical and structural characteristics of poplar cell walls were investigated before and after sodium hydroxide pretreatment (121 oC, 2%) to understand the alterations in biomass cellular structure, which were correlated with saccharification yield. Results showed that alkali pretreatment preferentially removed lignin from the S2 of fibers, which was similar to the behaviors of coniferyl al...

  18. EVALUATION OF COMPOSITION, CHARACTERIZATION AND ENZYMATIC HYDROLYSIS OF PRETREATED SUGAR CANE BAGASSE

    OpenAIRE

    A. A. Guilherme; Dantas,P. V. F.; Santos, E.S.; FERNANDES F. A. N.; G. R. Macedo

    2015-01-01

    Abstract Glucose production from sugarcane bagasse was investigated. Sugarcane bagasse was pretreated by four different methods: combined acid and alkaline, combined hydrothermal and alkaline, alkaline, and peroxide pretreatment. The raw material and the solid fraction of the pretreated bagasse were characterized according to the composition, SEM, X-ray and FTIR analysis. Glucose production after enzymatic hydrolysis of the pretreated bagasse was also evaluated. All these results were used to...

  19. The Impact of Post-Pretreatment Conditioning on Enzyme Accessibility and Water Interactions in Alkali Pretreated Rice Straw

    Science.gov (United States)

    Karuna, Nardrapee

    Rice straw, a high-abundance lignocellulosic residue from rice production has tremendous potential as a feedstock for biofuel production in California. In this study, the impact of post-alkali pretreatment conditioning schemes on enzyme saccharification efficiency was examined, particularly focusing on understanding resulting biomass compositional impacts on water interactions with the biomass and enzyme accessibility to the cellulose fraction. Rice straw was pretreated with sodium hydroxide and subsequently washed by two different conditions: 1) by extensive washing with distilled water to reduce the pH to the optimum for cellulases which is pH 5--6, and 2) immediate pH adjustment to pH 5--6 with hydrochloric acid before extensive washing with distilled water. The two post-pretreatment conditions gave significant differences in ash, acid-insoluble lignin, glucan and xylan compositions. Alkali pretreatment improved cellulase digestibility of rice straw, and water washing improved enzymatic digestibility more than neutralization. Hydrolysis reactions with a purified Trichoderma reesei Cel7A, a reducing-end specific cellulase, demonstrated that the differences in saccharification are likely due to differences in the accessibility of the cellulose fraction to the cellulolytic enzymes. Further analyses were conducted to study the mobility of the water associated with the rice straw samples by measuring T2 relaxation times of the water protons by 1H-Nuclear Magnetic Resonance (NMR) relaxometry. Results showed significant changes in water association with the rice straw due to the pretreatment and due to the two different post-pretreatment conditions. Pretreatment increased the amount of water at the surface of the rice straw samples as indicated by increased amplitude of the shortest T2 time peaks in the relaxation spectra. Moreover, the amount of water in the first T2 pool in the water washed sample was significantly greater than in the neutralized sample. These

  20. Enzymatic hydrolysis and fermentability of corn stover pretreated by lactic acid and/or acetic acid

    DEFF Research Database (Denmark)

    Xu, Jian; Thomsen, Mette Hedegaard; Thomsen, Anne Belinda

    2009-01-01

    Four different pretreatments with and without addition of low concentration organic acids were carried out on corn stover at 195 °C for 15 min. The highest xylan recovery of 81.08% was obtained after pretreatment without acid catalyst and the lowest of 58.78% after pretreatment with both acetic...

  1. Biological pretreatment of corn stover with white-rot fungus for improved enzymatic hydrolysis

    Science.gov (United States)

    Biological pretreatment of lignocellulosic biomass by white-rot fungus can represent a low-cost and eco-friendly alternative to harsh physical, chemical or physico-chemical pretreatment methods to facilitate enzymatic hydrolysis. However, fungal pretreatment can cause carbohydrate loss and it is, th...

  2. Comparisons of five Saccharomyces cerevisiae strains for ethanol production from SPORL pretreated lodgepole pine

    Science.gov (United States)

    The performances of 5 yeast strains under three levels of toxicity were evaluated using hydrolysates from lodgepole pine pretreated by Sulfite Pretreatment to Overcome the Recalcitrance of Lignocelluloses (SPORL). The highest level of toxicity was represented by the whole pretreated biomass slurry, ...

  3. Effect of thermal, chemical and thermo-chemical pre-treatments to enhance methane production

    DEFF Research Database (Denmark)

    Rafique, Rashad; Poulsen, Tjalfe; Nizami, Abdul-Sattar

    2010-01-01

    -treatments: thermal, thermo-chemical and chemical pre-treatments on the biogas and methane potential of dewatered pig manure. A laboratory scale batch digester is used for these pre-treatments at different temperature range (25 degrees C-150 degrees C). Results showed that thermo-chemical pretreatment has high effect...

  4. The design of a novel, environmentally improved, industrial cotton pre-treatment process

    NARCIS (Netherlands)

    Bouwhuis, Gerhard Herman

    2011-01-01

    The scope of this thesis is the development of a new industrial applicable pre-treatment process for cotton based on catalysis. The pre-treatment generally consists of desizing, scouring and bleaching. These processes can be continuous or batch wise. Advances in the science of biocatalytic pre-treat

  5. The impact of alkali pretreatment and post-pretreatment conditioning on the surface properties of rice straw affecting cellulose accessibility to cellulases.

    Science.gov (United States)

    Karuna, Nardrapee; Zhang, Lu; Walton, Jeffrey H; Couturier, Marie; Oztop, Mecit H; Master, Emma R; McCarthy, Michael J; Jeoh, Tina

    2014-09-01

    Rice straw was pretreated with sodium hydroxide and subsequently conditioned to reduce the pH to 5-6 by either: (1) extensive water washing or (2) acidification with hydrochloric acid then water washing. Alkali pretreatment improved the enzymatic digestibility of rice straw by increasing the cellulose accessibility to cellulases. However, acidification after pretreatment reversed the gains in cellulose accessibility to cellulases and enzymatic digestibility due to precipitation of solubilized compounds. Surface composition analyses by ToF-SIMS confirmed a reduction in surface lignin by pretreatment and water washing, and suggested that acidification precipitated a chemically modified form of lignin on the surfaces of rice straw. The spin-spin relaxation times (T2) of the samples indicated increased porosity in alkali pretreated rice straw. The acidified pretreated rice straw had reduced amounts of water in the longer T2 proton pools associated with water in the pores of the biomass likely due to back-filling by the precipitated components.

  6. The influence of pretreatment with ghrelin on the development of acetic-acid-induced colitis in rats.

    Science.gov (United States)

    Maduzia, D; Matuszyk, A; Ceranowicz, D; Warzecha, Z; Ceranowicz, P; Fyderek, K; Galazka, K; Dembinski, A

    2015-12-01

    Ghrelin has been primarily shown to exhibit protective and therapeutic effect in the gut. Pretreatment with ghrelin inhibits the development of acute pancreatitis and accelerates pancreatic recovery in the course of this disease. In the stomach, ghrelin reduces gastric mucosal damage induced by ethanol, stress or alendronate, as well as accelerates the healing of acetic acid-induced gastric and duodenal ulcer. The aim of present studies was to investigate the effect of pretreatment with ghrelin on the development of acetic acid-induced colitis. Studies have been performed on male Wistar rats. Animals were treated intraperitoneally with saline (control) or ghrelin (4, 8 or 16 nmol/kg/dose). Saline or ghrelin was given twice: 8 and 1 h before induction of colitis. Colitis was induced by a rectal enema with 1 ml of 4% solution of acetic acid and the severity of colitis was assessed 1 or 24 hours after induction of inflammation. Rectal administration of acetic acid induced colitis in all animals. Damage of colonic wall was seen at the macroscopic and microscopic level. This effect was accompanied by a reduction in colonic blood flow and mucosal DNA synthesis. Moreover, induction of colitis significantly increased mucosal concentration of pro-inflammatory interleukin-1β (IL-1β), activity of myeloperoxidase and concentration of malondialdehyde (MDA). Mucosal activity of superoxide dismutase (SOD) was reduced. Pretreatment with ghrelin reduced the area and grade of mucosal damage. This effect was accompanied by an improvement of blood flow, DNA synthesis and SOD activity in colonic mucosa. Moreover, ghrelin administration reduced mucosal concentration of IL-1β and MDA, as well as decreased mucosal activity of myeloperoxidase. Administration of ghrelin protects the large bowel against the development of the acetic acid-induced colitis and this effect seems to be related to the ghrelin-evoked anti-inflammatory and anti-oxidative effects.

  7. Effects of glutamine pretreatment on learning and memory in heat-exposed rats

    Institute of Scientific and Technical Information of China (English)

    Shenghao Zhao; Lei Wang; Qin Wang; Siyi Wang; Chundi Deng; Xianfei Xie; Youe Yan; Hui Wang

    2008-01-01

    BACKGROUND: Glutamine (Gln) pretreatment can protect neural cells from injuries due to heat, ischemia, hypoxia, endotoxemia, and inflammatory factors.OBJECTIVE: To observe the effects of Gln pretreatment on learning and memory, survival time, and rectal temperature in heat-exposed rats.DESIGN, TIME AND SETTING: The present randomized grouping, neurobehavioral experiment was performed at the Laboratory of Department of Pharmacology, Basic School of Medicine, Wuhan University between March and September 2007.MATERIALS: Twenty-four healthy, Wistar rats were included in this study. SPX-160B biochemistry incubator (Shanghai Experimental Equipment Co., Ltd., China), probe electronic thermometer (11000 type, Maikepai Science and Technology Co., Ltd., China), Y-type maze box used in conjunction with MG-2 maze stimulator (Zhangjiagang Biomedical Instrument Factory, China), L-Gin (Batch No. 061218, 5 g/bottle, prepared into 10% aqueous solution, Amresco Company, USA) were used.METHODS: Twenty-four rats were randomly and evenly divided into 3 groups: heat-exposed, Gln low-lose, and Gln high-dose. Following learning and memory testing with the Y-maze, rats in the heat-exposed group were subjected to heat injury (40.5-41.5℃) in a biochemistry incubator. Rectal temperature was measured every 5 minutes. Thirty-five minutes after heat exposure, rats were removed and placed in the Y-type maze to test learning and memory again. Subsequently, the rats were returned to the same environment of thermal stimulation until they died. Rat survival time was recorded. Subsequent to learning and memory testing, rats in the Gln low-dose and high-dose groups received an i.p. injection of Gln (0.4 g/kg and 0.8 g/kg, respectively), and were exposed to heat injury. The remaining experimental procedures remained the same as for the heat-exposed group.MAIN OUTCOME MEASURES: Rat learning and memory, rectal temperature, and survival time in heat exposure environment.RESULTS: (1) In the Y

  8. Biorefining of wheat straw: accounting for the distribution of mineral elements in pretreated biomass by an extended pretreatment – severity equation

    DEFF Research Database (Denmark)

    Le, Duy Michael; Sørensen, Hanne Risbjerg; Knudsen, Niels Ole

    2014-01-01

    Background: Mineral elements present in lignocellulosic biomass feedstocks may accumulate in biorefinery process streams and cause technological problems, or alternatively can be reaped for value addition. A better understanding of the distribution of minerals in biomass in response to pretreatment......, and treatment time), and to assess whether it is possible to model mineral levels in the pretreated fiber fraction. Results: Principal component analysis of the wheat straw biomass constituents, including mineral elements, showed that the recovered levels of wheat straw constituents after different hydrothermal...... fiber fractions. A new expanded pretreatment-severity equation is proposed to model and predict mineral composition in pretreated wheat straw biomass...

  9. Effects of an Agaricus blazei Aqueous Extract Pretreatment on Paracetamol-Induced Brain and Liver Injury in Rats

    Directory of Open Access Journals (Sweden)

    Andréia A. Soares

    2013-01-01

    Full Text Available The action of an Agaricus blazei aqueous extract pretreatment on paracetamol injury in rats was examined not only in terms of the classical indicators (e.g., levels of hepatic enzymes in the plasma but also in terms of functional and metabolic parameters (e.g., gluconeogenesis. Considering solely the classical indicators for tissue damage, the results can be regarded as an indication that the A. blazei extract is able to provide a reasonable degree of protection against the paracetamol injury in both the hepatic and brain tissues. The A. blazei pretreatment largely prevented the increased levels of hepatic enzymes in the plasma (ASP, ALT, LDH, and ALP and practically normalized the TBARS levels in both liver and brain tissues. With respect to the functional and metabolic parameters of the liver, however, the extract provided little or no protection. This includes morphological signs of inflammation and the especially important functional parameter gluconeogenesis, which was impaired by paracetamol. Considering these results and the long list of extracts and substances that are said to have hepatoprotective effects, it would be useful to incorporate evaluations of functional parameters into the experimental protocols of studies aiming to attribute or refute effective hepatoprotective actions to natural products.

  10. Pretreatment Hepatoprotective Effect of the Marine Fungus Derived from Sponge on Hepatic Toxicity Induced by Heavy Metals in Rats

    Directory of Open Access Journals (Sweden)

    Nehad M. Abdel-Monem

    2013-01-01

    Full Text Available The aim of this study was to evaluate the pretreatment hepatoprotective effect of the extract of marine-derived fungus Trichurus spiralis Hasselbr (TS isolated from Hippospongia communis sponge on hepatotoxicity. Twenty-eight male Sprague-Dawley rats were divided into four groups (n=7. Group I served as −ve control, group II served as the induced group receiving subcutaneously for seven days 0.25 mg heavy metal mixtures, group III received (i.p. TS extract of dose 40 mg for seven days, and group IV served as the protected group pretreated with TS extract for seven days as a protection dose, and then treated with the heavy metal-mixture. The main pathological changes within the liver after heavy-metal mixtures administrations marked hepatic damage evidenced by foci of lobular necrosis with neutrophilic infiltration, adjacent to dysplastic hepatocytes. ALT and AST measurements show a significant increase in group II by 46.20% and 45.12%, respectively. Total protein, elevated by about 38.9% in induction group compared to the −ve control group, in contrast to albumin, decreased as a consequence of metal administration with significant elevation on bilirubin level. The results prove that TS extract possesses a hepatoprotective property due to its proven antioxidant and free-radical scavenging properties.

  11. Metformin pretreatment enhanced learning and memory in cerebral forebrain ischaemia: the role of the AMPK/BDNF/P70SK signalling pathway.

    Science.gov (United States)

    Ghadernezhad, Negar; Khalaj, Leila; Pazoki-Toroudi, Hamidreza; Mirmasoumi, Masoumeh; Ashabi, Ghorbangol

    2016-10-01

    Context Metformin induced AMP-activated protein kinase (AMPK) and protected neurons in cerebral ischaemia. Objective This study examined pretreatment with metformin and activation of AMPK in molecular and behavioral levels associated with memory. Materials and methods Rats were pretreated with metformin (200 mg/kg) for 2 weeks and 4-vessels occlusion global cerebral ischaemia was induced. Three days after ischaemia, memory improvement was done by passive avoidance task and neurological scores were evaluated. The amount of Brain-Derived Neurotropic Factor (BDNF) and phosphorylated and total P70S6 kinase (P70S6K) were measured. Results Pretreatment with metformin (met) in the met + ischaemia/reperfusion (I/R) group reduced latency time for enter to dark chamber compared with the sham group (p BDNF compared with the I/R group (p BDNF decreased in the met + CC + I/R group compared with the met + I/R group (p ischaemia rats that were pretreated with metformin showed high levels of BDNF, P70S6K that seemed to be due to increasing AMPK.

  12. A real explosion: the requirement of steam explosion pretreatment.

    Science.gov (United States)

    Yu, Zhengdao; Zhang, Bailiang; Yu, Fuqiang; Xu, Guizhuan; Song, Andong

    2012-10-01

    The severity factor is a common term used in steam explosion (SE) pretreatment that describes the combined effects of the temperature and duration of the pretreatment. However, it ignores the duration of the explosion process. This paper describes a new parameter, the explosion power density (EPD), which is independent of the severity factor. Furthermore, we present the adoption of a 5m(3) SE model for a catapult explosion mode, which completes the explosion within 0.0875 s. The explosion duration ratio of this model to a conventional model of the same volume is 1:123. The comparison between the two modes revealed a qualitative change by explosion speed, demonstrating that this real explosion satisfied the two requirements of consistency, and suggested a guiding mechanism for the design of SE devices.

  13. Effect of ozone pretreatment on hydrogen production from barley straw.

    Science.gov (United States)

    Wu, Jiangning; Ein-Mozaffari, Farhad; Upreti, Simant

    2013-09-01

    Application of ozone technology to lignocellulosic biohydrogen production was explored with a barley straw. Ozone pretreatment effectively degraded the straw lignin and increased reducing sugar yield. A simultaneous enzyme hydrolysis and dark fermentation experiment was conducted using a mixed anaerobic consortium together with saccharification enzymes. Both untreated and ozonated samples produced hydrogen. Compared to the untreated group, hydrogen produced by the groups ozonated for 15, 30, 45 and 90 min increased 99%, 133%, 166% and 94%, respectively. Some inhibitory effect on hydrogen production was observed with the samples ozonated for 90 min, and the inhibition was on the fermentative microorganisms, not the saccharification enzymes. These results demonstrate that production of biohydrogen from barley straw, a lignocellulosic biomass, can be significantly enhanced by ozone pretreatment.

  14. Feasibilities of consolidated bioprocessing microbes: from pretreatment to biofuel production.

    Science.gov (United States)

    Parisutham, Vinuselvi; Kim, Tae Hyun; Lee, Sung Kuk

    2014-06-01

    Lignocelluloses are rich sugar treasures, which can be converted to useful commodities such as biofuel with the help of efficient combination of enzymes and microbes. Although several bioprocessing approaches have been proposed, biofuel production from lignocelluloses is limited because of economically infeasible technologies for pretreatment, saccharification and fermentation. Use of consolidated bioprocessing (CBP) microbes is the most promising method for the cost-effective production of biofuels. However, lignocelluloses are obtained from highly diverse environment and hence are heterogeneous in nature. Therefore, it is necessary to develop and integrate tailor-designed pretreatment processes and efficient microbes that can thrive on many different kinds of biomass. In this review, the progress towards the construction of consolidated bioprocessing microbes, which can efficiently convert heterogeneous lignocellulosic biomass to bioenergy, has been discussed; in addition, the potential and constraints of current bioprocessing technologies for cellulosic biofuel production have been discussed.

  15. PRETREATMENT TECHNOLOGIES IN BIOETHANOL PRODUCTION FROM LIGNOCELLULOSIC BIOMASS

    Directory of Open Access Journals (Sweden)

    Vanja Janušić

    2008-07-01

    Full Text Available Bioethanol is today most commonly produced from corn grain and sugar cane. It is expected that there will be limits to the supply of these raw materials in the near future. Therefore, lignocellulosic biomass, namely agricultural and forest waste, is seen as an attractive feedstock for future supplies of ethanol. Lignocellulosic biomass consists of lignin, hemicellulose and cellulose. Indeed, complexicity of the lignocellulosic biomass structure causes a pretreatment to be applied prior to cellulose and hemicellulose hydrolysis into fermentable sugars. Pretreatment technologies can be physical (mechanical comminution, pyrolysis, physico-chemical (steam explosion, ammonia fiber explosion, CO2 explosion, chemical (ozonolysis, acid hydrolysis, alkaline hydrolysis, oxidative delignification, organosolvent process and biological ones.

  16. Aspirin-induced human antral injury is reduced by vodka pretreatment.

    Science.gov (United States)

    Cohen, M M; Yeung, R; Kilam, S; Wang, H R

    1988-05-01

    Mild irritants have been shown to protect the rat gastric mucosa against noxious agents. This study was designed to test the protective potential of low-dose ethanol against acetylsalicylic acid (ASA) -induced gastric injury. Ten healthy volunteers who were nondrinkers and had normal baseline upper gastrointestinal endoscopy participated in a randomized double-blind crossover study. Thirty minutes after either vodka (37.5 ml) in tomato juice or tomato juice alone, each subject took 975 mg ASA and then underwent endoscopy 1 hr later. The degree of mucosal injury was scored, and blood was taken for ethanol and salicylate levels. There was a washout interval of seven days between the two treatments. Endoscopic scores were analyzed using the sign test. After a single dose of ASA, mucosal injury was confined to the fundus and antrum, while the duodenum was minimally affected. A significant reduction in antral damage was seen with ethanol pretreatment (P less than 0.05). The same trend was evident in the fundus but did not achieve statistical significance. Serum salicylate levels averaged 13.2 +/- 0.8 mg/100 ml and were not different between the two treatments. Ethanol concentration ranged from 1.1 to 6.2 mmol/liter following the vodka drink and was 0 after the placebo.

  17. Effects of Moxibustion Pretreating on SOD and MDA in the Rat of Global Brain Ischemia

    Institute of Scientific and Technical Information of China (English)

    HUA Jin-shuang; LI Li-ping; ZHU Xian-min

    2008-01-01

    objective;To probe into the mechanism of moxibustion preconditioning in preventive brain-protecting effect.Methods;The global brain ischemia rat model was developed by blocking 4 artenes.Seventy-eight Wistarmale rats were randomly divided into 5 groups;a nomal control group,a sham-operation group,a brain ischemia group,a brain ischemia preconditioning group,a moxibustion pretreating group.The brains in the 5groups were taken at 24 h,48h,and 72h after operation respectively Superoxide dismulase(SOD)activity was determined with xanthine oxidase method and malondialdehyde(MDA)content with thiobarbituric acid method.Results;After the operation,in the moxibustion preconditioning group,SOD activity significantly increased,especially 24h after moxibustion preconditioning;and MDA content decreased,with a very significant difference as compared with that of the cerebral ischemia group(P<0.01).Conclusion;Moxibustion preconditioning protects the ischemic and anoxic brain tissue by increasing the activity of endogenous antioxidase.

  18. Alkaline Pretreatment of Sweet Sorghum Bagasse for Bioethanol Production

    Directory of Open Access Journals (Sweden)

    Yanni Sudiyani

    2016-08-01

    Full Text Available Lignocellulosic material, which consist mainly of cellulose, hemicelluloses and lignin, are among the most promising renewable feedstocks for the production of energy and chemicals.   The bagasse residue of sweet sorghum can be utilized as raw material for alternative energy such as bioethanol.  Bioethanol production consists of pretreatment, saccharification, fermentation and purification process.  The pretreatment process was of great importance to ethanol yield.  In the present study, alkaline pretreatment was conducted using a steam explosion reactor at 1300C with concentrations of NaOH  6, and 10% (kg/L for 10, and 30 min.  For ethanol production separated hydrolysis and fermentation (SHF and simultaneous saccharification and fermentation (SSF process were conducted with 30 FPU of Ctec2 and Htec2 enzyme and yeast of Saccharomyces cerevisiae.   The results showed that maximum cellulose conversion to total glucose plus xylose were showed greatest with NaOH 10% for 30 min.  The highest yield of ethanol is 96.26% and high concentration of ethanol 66.88 g/L were obtained at SSF condition during 48 h process. Using SSF process could increase yields and concentration of ethanol with less energy process. Article History: Received January 16th 2016; Received in revised form May 25th 2016; Accepted June 28th 2016; Available online How to Cite This Article: Sudiyani, Y., Triwahyuni, E., Muryanto, Burhani, D., Waluyo, J. Sulaswaty, A. and Abimanyu, H. (2016 Alkaline Pretreatment of Sweet Sorghum Bagasse for Bioethanol Production. Int. Journal of Renewable Energy Development, 5(2, 113-118. http://dx.doi.org/10.14710/ijred.5.2.113-118 

  19. Understanding of alkaline pretreatment parameters for corn stover enzymatic saccharification

    OpenAIRE

    Chen Ye; Stevens Mark A; Zhu Yongming; Holmes Jason; Xu Hui

    2013-01-01

    Abstract Background Previous research on alkaline pretreatment has mainly focused on optimization of the process parameters to improve substrate digestibility. To achieve satisfactory sugar yield, extremely high chemical loading and enzyme dosages were typically used. Relatively little attention has been paid to reduction of chemical consumption and process waste management, which has proven to be an indispensable component of the bio-refineries. To indicate alkali strength, both alkali conce...

  20. Gasification performance of switchgrass pretreated with torrefaction and densification

    Energy Technology Data Exchange (ETDEWEB)

    Jaya Shankar Tumuluru; Various

    2014-08-01

    The purpose of this study was to investigate gasification performance of four switchgrass pretreatments (torrefaction at 230 and 270 °C, densification, and combined torrefaction and densification) and three gasification temperatures (700, 800 and 900 °C). Gasification was performed in a fixed-bed externally heated reactor with air as an oxidizing agent. Switchgrass pretreatment and gasification temperature had significant effects on gasification performance such as gas yields, syngas lower heating value (LHV), and carbon conversion and cold gas efficiencies. With an increase in the gasification temperature, yields of H2 and CO, syngas LHV, and gasifier efficiencies increased whereas CH4, CO2 and N2 yields decreased. Among all switchgrass pretreatments, gasification performance of switchgrass with combined torrefaction and densification was the best followed by that of densified, raw and torrefied switchgrass. Gasification of combined torrefied and densified switchgrass resulted in the highest yields of H2 (0.03 kg/kg biomass) and CO (0.72 kg/kg biomass), highest syngas LHV (5.08 MJ m-3), CCE (92.53%), and CGE (68.40%) at the gasification temperature of 900 °C.

  1. Microstructural study of pre-treated and enzymatic hydrolyzed bamboo

    Directory of Open Access Journals (Sweden)

    Funsho O. KOLAWOLE

    2016-07-01

    Full Text Available Bamboo was used as biomass feedstock which was pre-treated using dilute acid hydrolysis followed by enzymatic hydrolysis. The bamboo was mechanical ground to particle sizes 212–500µm, followed by pre-treatment with dilute sulfuric acid at a concentration of 0.5 and 1.0 (%v/v at temperatures of 25, 110, 120, 150 and 200°C with time intervals of 2 and 4 hours. Pre-hydrolyzate was later analyzed for reducing sugar using UV-Vis spectrophotometry. Under the above conditions, a maximum glucose yield of 153.1 mg/g was obtained at 200°C and acid concentrations of 1% for 4 hours. Water insoluble solids obtained were subsequently hydrolyzed with Celluclast (Trichoderma reesi and β-glucosidase (Novozyme 188 for 72 hours. Optical Microscope and ESEM images of bamboo samples were obtained at various stages of pre-treatment and enzymatic hydrolysis. Result reveals a breakdown in the ligno-cellulosic structure of the bamboo during exposure to dilute acid and enzymatic hydrolysis.

  2. The pretreatment cost of a pyroprocess facility in Korea

    Energy Technology Data Exchange (ETDEWEB)

    Kim, S. K.; Youn, S. R.; Lee, S. H.; Lee, H. J.; Ko, W. I. [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2015-05-15

    Shale gas still has many disadvantages such as significant technological difficulties and high costs even when the fracking technology is used to extract shale gas since shale gas is dispersed widely. Moreover, it is estimated that the shale gas can be used for about 60 years, which is comparable to the period estimated for oil deposits. Another concern is that the climate may change due to the discharge of harmful gas produced during the gas extraction process. PRIDE facility producing 10 ton/year uranium ingot was set as the cost object for the cost estimation, and it was possible to increase cost calculation's accuracy level since labor cost and expenses incurred in this facility were the costs incurred in actuality. In the end, First-In, First Out process costing method was used to calculate the pretreatment cost of pyroprocess. According to the cost calculation results, the pretreatment cost was estimated as $195/kgHM and the cost share of the pretreatment of pyroprocess was calculated as 20%. Accordingly, electrochemical reduction process is the process requires most cost, followed by the cost of electro-winning process.

  3. Nanofiltration based water reclamation from tannery effluent following coagulation pretreatment.

    Science.gov (United States)

    Dasgupta, J; Mondal, D; Chakraborty, S; Sikder, J; Curcio, S; Arafat, H A

    2015-11-01

    Coagulation-nanofiltration based integrated treatment scheme was employed in the present study to maximize the removal of toxic Cr(VI) species from tannery effluents. The coagulation pretreatment step using aluminium sulphate hexadecahydrate (alum) was optimized by response surface methodology (RSM). A nanofiltration unit was integrated with this coagulation pre-treatment unit and the resulting flux decline and permeate quality were investigated. Herein, the coagulation was conducted under response surface-optimized operating conditions. The hybrid process demonstrated high chromium(VI) removal efficiency over 98%. Besides, fouling of two of the tested nanofiltration membranes (NF1 and NF3) was relatively mitigated after feed pretreatment. Nanofiltration permeation fluxes as high as 80-100L/m(2)h were thereby obtained. The resulting permeate stream quality post nanofiltration (NF3) was found to be suitable for effective reuse in tanneries, keeping the Cr(VI) concentration (0.13mg/L), Biochemical Oxygen Demand (BOD) (65mg/L), Chemical Oxygen Demand (COD) (142mg/L), Total Dissolved Solids (TDS) (108mg/L), Total Solids (TS) (86mg/L) and conductivity levels (14mho/cm) in perspective. The process water reclaiming ability of nanofiltration was thereby substantiated and the effectiveness of the proposed hybrid system was thus affirmed.

  4. Calcium pretreatment increases thermotolerance of Laminaria japonica sporophytes

    Institute of Scientific and Technical Information of China (English)

    You Wang; Qingyun Yu; Xuexi Tang; Lili Wang

    2009-01-01

    Calcium is a secondary messenger in plant signaling,and its concentration changes spatially and temporally during the course of heat stress.In the present study,potassium antimonate was used to visualize calcium localization in blades of a marine macroalga,the juvenile Laminariajaponica sporophytes under heat stress (25 ℃).Result showed that loosely bound calcium was mainly distributed on the cell wall under normal conditions (10 ℃),and flowed into the cytoplasm when exposed to heat.The simutaneous assay on the antioxidant system changes was performed.Oxidative damage,as measured by generation of reactive oxygen species (ROS) malondialdehyde (MDA) content,increased significantly during heat stress,and calcium pretreatment alleviated oxidative damage.The assay on the activities of six antioxidant enzymes demonstrated that their enzymatic activities were inhibited when exposed to heat stress,but Ca2+ pretreatment effectively attenuated the inhibition.Results in the present study inferred that calcium homeostasis plays an essential role in L.japonica sporophyte when exposed to heat,and calcium pretreatment could improve its thermo-tolerance.

  5. Enhanced biomethanation of kitchen waste by different pre-treatments.

    Science.gov (United States)

    Ma, Jingxing; Duong, Thu Hang; Smits, Marianne; Verstraete, Willy; Carballa, Marta

    2011-01-01

    Five different pre-treatments were investigated to enhance the solubilisation and anaerobic biodegradability of kitchen waste (KW) in thermophilic batch and continuous tests. In the batch solubilisation tests, the highest and the lowest solubilisation efficiency were achieved with the thermo-acid and the pressure-depressure pre-treatments, respectively. However, in the batch biodegradability tests, the highest cumulative biogas production was obtained with the pressure-depressure method. In the continuous tests, the best performance in terms of an acceptable biogas production efficiency of 60% and stable in-reactor CODs and VFA concentrations corresponded to the pressure-depressure reactor, followed by freeze-thaw, acid, thermo-acid, thermo and control. The maximum OLR (5 g COD L(-1) d(-1)) applied in the pressure-depressure and freeze-thaw reactors almost doubled the control reactor. From the overall analysis, the freeze-thaw pre-treatment was the most profitable process with a net potential profit of around 11.5 € ton(-1) KW.

  6. Description of waste pretreatment and interfacing systems dynamic simulation model

    Energy Technology Data Exchange (ETDEWEB)

    Garbrick, D.J.; Zimmerman, B.D.

    1995-05-01

    The Waste Pretreatment and Interfacing Systems Dynamic Simulation Model was created to investigate the required pretreatment facility processing rates for both high level and low level waste so that the vitrification of tank waste can be completed according to the milestones defined in the Tri-Party Agreement (TPA). In order to achieve this objective, the processes upstream and downstream of the pretreatment facilities must also be included. The simulation model starts with retrieval of tank waste and ends with vitrification for both low level and high level wastes. This report describes the results of three simulation cases: one based on suggested average facility processing rates, one with facility rates determined so that approximately 6 new DSTs are required, and one with facility rates determined so that approximately no new DSTs are required. It appears, based on the simulation results, that reasonable facility processing rates can be selected so that no new DSTs are required by the TWRS program. However, this conclusion must be viewed with respect to the modeling assumptions, described in detail in the report. Also included in the report, in an appendix, are results of two sensitivity cases: one with glass plant water recycle steams recycled versus not recycled, and one employing the TPA SST retrieval schedule versus a more uniform SST retrieval schedule. Both recycling and retrieval schedule appear to have a significant impact on overall tank usage.

  7. ETHANOL ORGANOSOLV PRETREATMENT OF BAMBOO FOR EFFICIENT ENZYMATIC SACCHARIFICATION

    Directory of Open Access Journals (Sweden)

    Zhiqiang Li,

    2012-06-01

    Full Text Available Bamboo is a potential lignocellulosic biomass for the production of bioethanol because of its high cellulose and hemicelluloses content. In this research, ethanol organosolv pretreatment with dilute sulfuric acid as the catalyst was studied in order to enhance enzymatic saccharification of moso bamboo. The addition of 2% (w/w bamboo dilute sulfuric acid in 75% ethanol had a particularly strong effect on fractionation of bamboo. It yielded a solids fraction containing 83.4% cellulose in the treated substrate. The cellulose conversion to glucose yield reached 77.1 to 83.4% after enzymatic hydrolysis of the solids fraction for 48 h at an enzyme loading of 15 FPU cellulase/g cellulose and 30 IU β-glucosidase/g cellulose. The enzymatic hydrolysis rate was significantly accelerated as the ethanol organosolv pretreatment time increased, reaching the highest enzymatic glucose yield of 83.4% after 48 h at 50 °C. The concentrations of fermentation inhibitors such as HMF (5-hydroxy-2-methyl furfural and furfural were 0.96 g/L and 4.38 g/L in the spent liquor after the ethanol organosolv pretreatment, which were slightly lower than the concentrations quantified during H2SO4-water treatment. Spent liquor was diluted with water, and more than 87.2% of lignin in raw bamboo was recovered as ethanol organosolv lignin through the filtration process.

  8. Pretreatment of coking wastewater using anaerobic sequencing batch reactor (ASBR)

    Institute of Scientific and Technical Information of China (English)

    LI Bing; SUN Ying-lan; LI Yu-ying

    2005-01-01

    A laboratory-scale anaerobic sequencing batch reactor (ASBR) was used to pretreat coking wastewater. Inoculated anaerobic granular biomass was acclimated for 225 d to the coking wastewater, and then the biochemical methane potential (BMP)of the coking wastewater in the acclimated granular biomass was measured. At the same time, some fundamental technological factors, such as the filling time and the reacting time ratio (tf/tr), the mixing intensity and the intermittent mixing mode, that affect anaerobic pretreatment of coking wastewater with ASBR, were evaluated through orthogonal tests. The COD removal efficiency reached 38%~50% in the stable operation period with the organic loading rate of 0.37~0.54 kg COD/(m3.d) at the optimum conditions of tf/tr, the mixing intensity and the intermittent mixing mode. In addition, the biodegradability of coking wastewater distinctly increased after the pretreatment using ASBR. At the end of the experiment, the microorganism forms on the granulated sludge in the ASBR were observed using SEM (scanning electron microscope) and fluoroscope. The results showed that the dominant microorganism on the granular sludge was Methanosaeta instead of Methanosarcina dominated on the inoculated sludge.

  9. Digestibility Improvement of Sorted Waste with Alkaline Hydrothermai Pretreatment

    Institute of Scientific and Technical Information of China (English)

    WANG Hao; WANG Hongtao; LU Wenjing; ZHAO Yan

    2009-01-01

    The digestibility of sorted municipal solid waste (MSW) is often limited by the high content of structured green waste. The objectives of this study are to investigate the effect of alkaline hydrothermal pretreatment on the anaerobic digestion of sorted waste and to analyze the biogas production of different parts of the waste. The waste was hydrothermally pretreated in a dilute alkali solution. The hydrolysis product was then incubated in a 500 mL saline bottle to determine the biochemical methane potential (BMP) under mesophilic anaerobic conditions. The optimum hydrothermal condition was 170℃ at 4 g NaOH/100 g solid for one hour. The concentration of chemical oxygen demand (COD) was 13 936 mg/L and the methane yield was 164 mL/g volatile solid (VS) for 6 days incubation at the optimum conditions. The biogas production was increased more than 50% over the control, with the methane conversion ratio on a carbon basis enhanced to 30.6%. The organic part of the sorted waste was mainly kitchen garbage and leaves. Model kitchen garbage completely liquified at 130℃ for one hour had a methane yield of 276 mL/g VS. The alkali addition slightly enhanced the hydrolyzation rate and methane yield. The biogas potential of leaves was improved by pre-treatment at above 150℃ under alkaline conditions.

  10. Woody biomass pretreatment for cellulosic ethanol production: Technology and energy consumption evaluation.

    Science.gov (United States)

    Zhu, J Y; Pan, X J

    2010-07-01

    This review presents a comprehensive discussion of the key technical issues in woody biomass pretreatment: barriers to efficient cellulose saccharification, pretreatment energy consumption, in particular energy consumed for wood-size reduction, and criteria to evaluate the performance of a pretreatment. A post-chemical pretreatment size-reduction approach is proposed to significantly reduce mechanical energy consumption. Because the ultimate goal of biofuel production is net energy output, a concept of pretreatment energy efficiency (kg/MJ) based on the total sugar recovery (kg/kg wood) divided by the energy consumption in pretreatment (MJ/kg wood) is defined. It is then used to evaluate the performances of three of the most promising pretreatment technologies: steam explosion, organosolv, and sulfite pretreatment to overcome lignocelluloses recalcitrance (SPORL) for softwood pretreatment. The present study found that SPORL is the most efficient process and produced highest sugar yield. Other important issues, such as the effects of lignin on substrate saccharification and the effects of pretreatment on high-value lignin utilization in woody biomass pretreatment, are also discussed.

  11. Efficient pretreatment of Vietnamese rice straw by soda and sulfate cooking methods for enzymatic saccharification.

    Science.gov (United States)

    Dien, Le Quang; Phuong, Nguyen Thi Minh; Hoa, Doan Thai; Hoang, Phan Huy

    2015-02-01

    This manuscript presents a study on alkaline pretreatment of Vietnamese rice (Oryza sativa L.) straw that grows in Northern Vietnam for enzymatic saccharification. The NaOH pretreatment (soda cooking) and NaOH/Na2S pretreatment (sulfate cooking) were applied for rice straw pretreatment, which have relatively similar condition with industrial pulping processes but at lower temperature. Pretreated biomass solid was then enzymatic hydrolyzed by commercial enzyme Cellic®CTec2 (Novozymes) with enzyme dosage of 35 FPU/g to achieve reducing sugars. The suitable condition for pretreatment was found at temperature of about 100 °C, pretreatment time of 2 h, and solid/liquid ratio of 1:10 with active alkali dosage of 20 % of dry rice straw. Under this pretreatment condition, sugar yield in enzymatic hydrolysis up to 45.33 and 48.92 % over dry rice straw could be obtained after soda cooking and sulfate cooking pretreatment, respectively. Moreover, the changes of components of rice straw after pretreatment were also studied. The crystallinity of cellulose in pretreated biomass solid was calculated from XRD pattern. And the fibril morphology after treatment was revealed by the microscopic observations performed by scanning electron microscope (SEM).

  12. Mechanism of waste biomass pyrolysis: Effect of physical and chemical pre-treatments

    Energy Technology Data Exchange (ETDEWEB)

    Das, Oisik [Department of Biological Systems Engineering, Washington State University, Pullman 99164-6120, WA (United States); Department of Civil and Environmental Engineering, University of Auckland, Auckland 1142 (New Zealand); Sarmah, Ajit K., E-mail: a.sarmah@auckland.ac.nz [Department of Civil and Environmental Engineering, University of Auckland, Auckland 1142 (New Zealand)

    2015-12-15

    To impart usability in waste based biomass through thermo-chemical reactions, several physical and chemical pre-treatments were conducted to gain an insight on their mode of action, effect on the chemistry and the change in thermal degradation profiles. Two different waste biomasses (Douglas fir, a softwood and hybrid poplar, a hardwood) were subjected to four different pre-treatments, namely, hot water pre-treatment, torrefaction, acid (sulphuric acid) and salt (ammonium phosphate) doping. Post pre-treatments, the changes in the biomass structure, chemistry, and thermal makeup were studied through electron microscopy, atomic absorption/ultra violet spectroscopy, ion exchange chromatography, and thermogravimetry. The pre-treatments significantly reduced the amounts of inorganic ash, extractives, metals, and hemicellulose from both the biomass samples. Furthermore, hot water and torrefaction pre-treatment caused mechanical disruption in biomass fibres leading to smaller particle sizes. Torrefaction of Douglas fir wood yielded more solid product than hybrid poplar. Finally, the salt pre-treatment increased the activation energies of the biomass samples (especially Douglas fir) to a great extent. Thus, salt pre-treatment was found to bestow thermal stability in the biomass. - Highlights: • Pre-treatments reduce ash, extractives, alkalines and hemicellulose from biomass. • Torrefaction of Douglas fir yields more solid product than hybrid poplar. • Salt pretreatment significantly increases the activation energy of biomass. • Acid and salt pretreatment bestows thermal stability in biomass.

  13. Microwave pretreatment can enhance tolerance of wheat seedlings to CdCl2 stress.

    Science.gov (United States)

    Qiu, ZongBo; Li, JinTing; Zhang, YaJie; Bi, ZhenZhen; Wei, HuiFang

    2011-05-01

    In order to determine the role of microwave in cadmium stress tolerance of wheat (Triticum aestivum L.), seeds were exposed to microwave radiation for 0, 5, 10 and 15 s (wavelength 125 mm, power density 126 mW cm(-2), 2450 MHz), and when the seedlings were 7 d old (with one fully expanded leaves), they were treated with 150 μM CdCl(2) solution for 10 d. Changes in a number of physiological and biochemical characteristics were measured and used as indicators of the protective capacity of microwave radiation in this experiment. Our results showed that 150 μM CdCl(2) treatment reduced plant height, root length, dry weight, AsA and GSH concentration and the activities of SOD, POD, CAT and APX, enhanced the concentration of MDA, H(2)O(2) and the production rate of O(2)- when compared with the control. However, seeds with microwave pretreatment 5 or 10 s conferred tolerance to cadmium stress in wheat seedlings by decreasing the concentration of MDA and H(2)O(2), the production rate of O(2)- and increasing the activities of SOD, POD, CAT, APX and AsA and GSH concentration. Therefore, antioxidative enzymes and antioxidative compounds may participate in tolerance of wheat seedlings to cadmium stress. The results also showed that the microwave radiation had a positive physiological effect on the growth and development of cadmium stressed seedlings. This is the first investigation reporting the use of microwave pretreatment to enhance cadmium stress tolerance of wheat.

  14. Impacts of Greening Materials and Seed Pretreatment on Vegetation Development at an initial stage

    Science.gov (United States)

    Obriejetan, Michael

    2015-04-01

    Slope protection using greening measures as an integral part of soil-bioengineering is characterized by an increasing demand in research and practice. However, successful greening is a very complex issue due to the vast variety in specific slope characteristics such as morphology, soil properties and environmental factors. Because of practical experience in the greening of slopes and the results of further investigations in small-scale tests, it can be stated that the use of appropriate planting techniques, the quality of the materials used and the proper implementation of potential needed auxiliary materials at difficult locations are seen as key success criteria for sustainable vegetation development. Within this framework small-scale testing series were conducted regarding the influence of specific soil-properties, the use of auxiliary greening materials (fertilizer, mycorrhiza fungi, Bonded fiber matrix (BFM)…), application of different seed-pretreatment methods and influences of specific environmental factors (inclination, seeding depth) on vegetational development in an early phase. The aim of the series is to quantitatively and thus economically optimize the use of different greening-components and seed mixtures for practical application, while ensuring optimal development of vegetation. To quantify the influence of the treatment systems, vegetation cover ratio, biomass production (aboveground and belowground) and the germination of plant seeds served as main criteria for assessing the development in an initial stage. Selected findings for instance show that the admixture of mycorrhiza fungi can increase the cover ratio up to 23 % compared to untreated plots. In addition, pretreatment of seeds showed distinct effects too by shortening germination phase and increasing the capability of producing a higher amount of healthy sprouts. From a bioengineering perspective the results will serve as potential decisive advantage for successful implementation of

  15. Biogas production and saccharification of Salix pretreated at different steam explosion conditions.

    Science.gov (United States)

    Horn, Svein J; Estevez, Maria M; Nielsen, Henrik K; Linjordet, Roar; Eijsink, Vincent G H

    2011-09-01

    Different steam explosion conditions were applied to Salix chips and the effect of this pretreatment was evaluated by running both enzymatic hydrolysis and biogas tests. Total enzymatic release of glucose and xylose increased with pretreatment harshness, with maximum values being obtained after pretreatment for 10 min at 210°C. Harsher pretreatment conditions did not increase glucose release, led to degradation of xylose and to formation of furfurals. Samples pretreated at 220 and 230°C initially showed low production of biogas, probably because of inhibitors produced during the pretreatment, but the microbial community was able to adapt and showed high final biogas production. Interestingly, final biogas yields correlated well with sugar yields after enzymatic hydrolysis, suggesting that at least in some cases a 24h enzymatic assay may be developed as a quick method to predict the effects of pretreatment of lignocellulosic biomass on biogas yields.

  16. Impact of thermal pretreatment on the fast pyrolysis conversion of Southern Pine

    Energy Technology Data Exchange (ETDEWEB)

    Tyler L. Westover; Manunya Phanphanich; Micael L. Clark; Sharna R. Rowe; Steven E. Egan; Christopher T Wright; Richard D. Boardman; Alan H. Zacher

    2013-01-01

    Background: Thermal pretreatment of biomass ranges from simple (nondestructive) drying to more severe treatments that cause devolatization, depolymerization and carbonization. These pretreatments have demonstrated promise for transforming raw biomass into feedstock material that has improved milling, handling, storage and conversion properties. In this work, southern pine material was pretreated at 120, 180, 230 and 270 degrees C, and then subjected to pyrolysis tests in a continuous-feed bubbling-fluid bed pyrolysis system. Results: High pretreatment temperatures were associated with lower specific grinding energies, higher grinding rates and lower hydrogen and oxygen contents. Higher pretreatment temperatures were also correlated with increased char production, decreased total acid number and slight decrease in the oxygen content of the pyrolysis liquid fraction. Conclusion: Thermal pretreatment has both beneficial and detrimental impacts on fast pyrolysis conversion of pine material to bio-oil, and the effect of thermal pretreatment on upgrading of pyrolysis bio-oil requires further attention.

  17. Impact of surfactant type for ionic liquid pretreatment on enhancing delignification of rice straw.

    Science.gov (United States)

    Chang, Ken-Lin; Chen, Xi-Mei; Wang, Xiao-Qin; Han, Ye-Ju; Potprommanee, Laddawan; Liu, Jing-Yong; Liao, Yu-Ling; Ning, Xun-An; Sun, Shui-Yu; Huang, Qing

    2017-03-01

    This work describes an environmentally friendly method for pretreating rice straw by using 1-Allyl-3-methylimidazolium chloride ([AMIM]Cl) as an ionic liquid (IL) assisted by surfactants. The impacts of surfactant type (including nonionic-, anionic-, cationic- and bio-surfactant) on the ionic liquid pretreatment were investigated. The bio-surfactant+IL-pretreated rice straw showed significant lignin removal (26.14%) and exhibited higher cellulose conversion (36.21%) than the untreated (16.16%) rice straw. The cellulose conversion of the rice straw pretreated with bio-surfactant+IL was the highest and the lowest was observed for pretreated with cationic-surfactant+IL. Untreated and pretreated rice straw was thoroughly characterized through SEM and AFM. In conclusion, the results provided an effective and environmental method for pretreating lignocellulosic substrates by using green solvent (ionic liquid) and biodegradable bio-surfactant.

  18. Biological pretreatment of corn stover with ligninolytic enzyme for high efficient enzymatic hydrolysis.

    Science.gov (United States)

    Wang, Feng-Qin; Xie, Hui; Chen, Wei; Wang, En-Tao; Du, Feng-Guang; Song, An-Dong

    2013-09-01

    Aiming at increasing the efficiency of transferring corn stover into sugars, a biological pretreatment was developed and investigated in this study. The protocol was characterized by the pretreatment with crude ligninolytic enzymes from Phanerochete chrysosporium and Coridus versicolor to break the lignin structure in corn stover, followed by a washing procedure to eliminate the inhibition of ligninolytic enzyme on cellulase. By a 2 d-pretreatment, sugar yield from corn stover hydrolysis could be increased by 50.2% (up to 323 mg/g) compared with that of the control. X-ray diffractometry and FT-IR analysis revealed that biological pretreatment could partially remove the lignin of corn stover, and consequently enhance the enzymatic hydrolysis efficiency of cellulose and hemeicellulose. In addition, the amount of microbial inhibitors, such as acetic acid and furfural, were much lower in biological pretreatment than that in acid pretreatment. This study provided a promising pretreatment method for biotransformation of corn stovers.

  19. Long term storage of dilute acid pretreated corn stover feedstock and ethanol fermentability evaluation.

    Science.gov (United States)

    Zhang, Jian; Shao, Shuai; Bao, Jie

    2016-02-01

    This study reported a new solution of lignocellulose feedstock storage based on the distributed pretreatment concept. The dry dilute sulfuric acid pretreatment (DDAP) was conducted on corn stover feedstock, instead of ammonia fiber explosion pretreatment. Then the dry dilute acid pretreated corn stover was stored for three months during summer season with high temperature and humidity. No negative aspects were found on the physical property, composition, hydrolysis yield and ethanol fermentability of the long term stored pretreated corn stover, plus the additional merits including no chemicals recovery operation, anti-microbial contaminant environment from stronger acid and inhibitor contents, as well as the mild and slow hydrolysis in the storage. The new pretreatment method expanded the distributed pretreatment concept of feedstock storage with potential for practical application.

  20. Glycation promoted by dynamic high pressure microfluidisation pretreatment revealed by high resolution mass spectrometry.

    Science.gov (United States)

    Huang, Xiaoqin; Tu, Zongcai; Wang, Hui; Zhang, Qiuting; Hu, Yueming; Zhang, Lan; Niu, Peipei; Shi, Yan; Xiao, Hui

    2013-12-01

    The effect of dynamic high pressure microfluidisation (DHPM) pretreatment on the glycation of bovine serum albumin (BSA) was investigated. A detailed glycation map was obtained from high resolution mass spectrometry. Without DHPM pretreatment, only 7 glycation sites were identified, whereas the numbers were increased to 10, 11 and 11 when BSA-glucose was pretreated with DHPM at 50, 100 and 200 MPa, respectively, suggesting that DHPM pretreatment can significantly promote the Maillard reaction. Average degree of substitution per peptide molecule BSA (DSP) was used to further evaluate the glycation level under various DHPM conditions. All the DHPM pretreated samples exhibited elevated glycation level compared to the un-pretreated sample. With 100 MPa DHPM pretreatment, the protein showed the most significantly enhanced glycation extent. In addition, our results suggest that Maillard-type glycation followed by mass spectrometry analysis can be used to study the conformational changes when proteins are disturbed by external forces.

  1. Microalgae conversion to biogas: thermal pretreatment contribution on net energy production.

    Science.gov (United States)

    Passos, Fabiana; Ferrer, Ivet

    2014-06-17

    Microalgal biomass harvested from wastewater treatment high rate algal ponds may be valorised through anaerobic digestion producing biogas. However, microalgae anaerobic biodegradability is limited by their complex cell wall structure. Thus, pretreatment techniques are being investigated to improve microalgae methane yield. In the current study, thermal pretreatment at relatively low temperatures of 75-95 °C was effective at enhancing microalgae anaerobic biodegradability; increasing the methane yield by 70% in respect to nonpretreated biomass. Microscopic images showed how the pretreatment damaged microalgae cells, enhancing subsequent anaerobic digestion. Indeed, digestate images showed how after pretreatment only species with resistant cell walls, such as diatoms, continued to be present. Energy balances based on lab-scale reactors performance at 20 days HRT, shifted from neutral to positive (energy gain around 2.7 GJ/d) after thermal pretreatment. In contrast with electricity consuming pretreatment methods, such as microwave irradiation, thermal pretreatment of microalgae seems to be scalable.

  2. Ultrasound pretreatment for enhanced biogas production from olive mill wastewater.

    Science.gov (United States)

    Oz, Nilgun Ayman; Uzun, Alev Cagla

    2015-01-01

    This study investigates applicability of low frequency ultrasound technology to olive mill wastewaters (OMWs) as a pretreatment step prior to anaerobic batch reactors to improve biogas production and methane yield. OMWs originating from three phase processes are characterized with high organic content and complex nature. The treatment of the wastewater is problematic and alternative treatment options should be investigated. In the first part of the study, OMW samples were subjected to ultrasound at a frequency of 20kHz with applied powers varying between 50 and 100W under temperature controlled conditions for different time periods in order to determine the most effective sonication conditions. The level of organic matter solubilization at ultrasound experiments was assessed by calculating the ratio of soluble chemical oxygen demand/total chemical oxygen demand (SCOD/TCOD). The results revealed that the optimum ultrasonic condition for diluted OMW is 20kHz, 0.4W/mL for 10min. The application of ultrasound to OMW increased SCOD/TCOD ratio from 0.59 to 0.79. Statistical analysis (Friedman's tests) show that ultrasound was significantly effective on diluted OMW (p0.05). For raw OMW, this increase has been found to be limited due to high concentration of suspended solids (SS). In the second part of the study, biogas and methane production rates of anaerobic batch reactor fed with the ultrasound pretreated OMW samples were compared with the results of control reactor fed with untreated OMW in order to determine the effect of sonication. A nonparametric statistical procedure, Mann-Whitney U test, was used to compare biogas and methane production from anaerobic batch reactors for control and ultrasound pretreated samples. Results showed that application of low frequency ultrasound to OMW significantly improved both biogas and methane production in anaerobic batch reactor fed with the wastewater (preactor fed with ultrasound pretreated diluted OMW produced approximately 20

  3. Relaxin protects astrocytes from hypoxia in vitro.

    Directory of Open Access Journals (Sweden)

    Jordan M Willcox

    Full Text Available The peptide relaxin has recently been shown to protect brain tissues from the detrimental effects of ischemia. To date, the mechanisms for this remain unclear. In order to investigate the neuroprotective mechanisms by which relaxin may protect the brain, we investigated the possibility that relaxin protects astrocytes from hypoxia or oxygen/glucose deprivation (OGD. Cultured astrocytes were pre-treated with either relaxin-2 or relaxin-3 and exposed to OGD for 24 or 48 hours. Following OGD exposure, viability assays showed that relaxin-treated cells exhibited a higher viability when compared to astrocytes that experienced OGD-alone. Next, to test whether relaxin reduced the production of reactive oxygen species (ROS astrocytes were exposed to the same conditions as the previous experiment and a commercially available ROS detection kit was used to detect ROS production. Astrocytes that were treated with relaxin-2 and relaxin-3 showed a marked decrease in ROS production when compared to control astrocytes that were exposed only to OGD. Finally, experiments were performed to determine whether or not the mitochondrial membrane potential was affected by relaxin treatment during 24 hour OGD. Mitochondrial membrane potential was higher in astrocytes that were treated with relaxin-2 and relaxin-3 compared to untreated OGD-alone astrocytes. Taken together, these data present novel findings that show relaxin protects astrocytes from ischemic conditions through the reduction of ROS production and the maintenance of mitochondrial membrane potential.

  4. Pretreating lignocellulosic biomass by the concentrated phosphoric acid plus hydrogen peroxide (PHP) for enzymatic hydrolysis: evaluating the pretreatment flexibility on feedstocks and particle sizes.

    Science.gov (United States)

    Wang, Qing; Wang, Zhanghong; Shen, Fei; Hu, Jinguang; Sun, Fubao; Lin, Lili; Yang, Gang; Zhang, Yanzong; Deng, Shihuai

    2014-08-01

    In order to seek a high-efficient pretreatment path for converting lignocellulosic feedstocks to fermentable sugars by enzymatic hydrolysis, the concentrated H₃PO₄ plus H₂O₂ (PHP) was attempted to pretreat different lignocellulosic biomass for evaluating the pretreatment flexibility on feedstocks. Meanwhile, the responses of pretreatment to particle sizes were also evaluated. When the PHP-pretreatment was employed (final H₂O₂ and H₃PO₄ concentration of 1.77% and 80.0%), 71-96% lignin and more than 95% hemicellulose in various feedstocks (agricultural residues, hardwood, softwood, bamboo, and their mixture, and garden wastes mixture) can be removed. Consequently, more than 90% glucose conversion was uniformly achieved indicating PHP greatly improved the pretreatment flexibility to different feedstocks. Moreover, when wheat straw and oak chips were PHP-pretreated with different sizes, the average glucose conversion reached 94.9% and 100% with lower coefficient of variation (7.9% and 0.0%), which implied PHP-pretreatment can significantly weaken the negative effects of feedstock sizes on subsequent conversion.

  5. Alkaline peroxide pretreatment of rapeseed straw for enhancing bioethanol production by Same Vessel Saccharification and Co-Fermentation

    DEFF Research Database (Denmark)

    Karagöz, Pinar; Vaitkeviciute-Rocha, Indre; Özkan, Melek;

    2012-01-01

    Alkaline peroxide pretreatment of rapeseed straw was evaluated for conversion of cellulose and hemicellulose to fermentable sugars. After pretreatment, a liquid phase called pretreatment liquid and a solid phase were separated by filtration. The neutralized pretreatment liquids were used in a co...

  6. Extrapolating from animal studies to the efficacy in humans of a pretreatment combination against organophosphate poisoning.

    Science.gov (United States)

    Levy, Aharon; Cohen, Giora; Gilat, Eran; Kapon, Joseph; Dachir, Shlomit; Abraham, Shlomo; Herskovitz, Miriam; Teitelbaum, Zvi; Raveh, Lily

    2007-05-01

    The extrapolation from animal data to therapeutic effects in humans, a basic pharmacological issue, is especially critical in studies aimed to estimate the protective efficacy of drugs against nerve agent poisoning. Such efficacy can only be predicted by extrapolation of data from animal studies to humans. In pretreatment therapy against nerve agents, careful dose determination is even more crucial than in antidotal therapy, since excessive doses may lead to adverse effects or performance decrements. The common method of comparing dose per body weight, still used in some studies, may lead to erroneous extrapolation. A different approach is based on the comparison of plasma concentrations at steady state required to obtain a given pharmacodynamic endpoint. In the present study, this approach was applied to predict the prophylactic efficacy of the anticholinergic drug caramiphen in combination with pyridostigmine in man based on animal data. In two species of large animals, dogs and monkeys, similar plasma concentrations of caramiphen (in the range of 60-100 ng/ml) conferred adequate protection against exposure to a lethal-dose of sarin (1.6-1.8 LD(50)). Pharmacokinetic studies at steady state were required to achieve the correlation between caramiphen plasma concentrations and therapeutic effects. Evaluation of total plasma clearance values was instrumental in establishing desirable plasma concentrations and minimizing the number of animals used in the study. Previous data in the literature for plasma levels of caramiphen that do not lead to overt side effects in humans (70-100 ng/ml) enabled extrapolation to expected human protection. The method can be applied to other drugs and other clinical situations, in which human studies are impossible due to ethical considerations. When similar dose response curves are obtained in at least two animal models, the extrapolation to expected therapeutic effects in humans might be considered more reliable.

  7. Protective effect induced by atropine, carbamates, and 2-pyridine aldoxime methoiodide Artemia salina larvae exposed to fonofos and phosphamidon.

    Science.gov (United States)

    Victoria Barahona, M; Sánchez-Fortún, Sebastián

    2007-01-01

    The acute toxicity of fonofos and phosphamidon on three age classes of Artemia salina was evaluated. An increase in toxicity of these organophosphorous (OP) insecticides was found following longer development of A. salina. The effects of pretreatment with the nonselective muscarinic antagonist atropine, the two reversible acetylcholinesterease inhibitors physostigmine and pyridostigmine, and the cholinesterase-reactivating oxime 2-pyridine aldoxime methoiodide (2-PAM), as individual and combined pretreatments, on OP-induced lethality in 24 h Artemia were also investigated. The lethal action of both OP insecticides was prevented by pretreatment of 24 h Artemia with atropine and 2-PAM, while physostigmine proved ineffective against intoxication with both OP insecticides and pyridostigmine exhibited a low synergic effect. In both cases, the inhibitory effects of combinations of atropine (10(-5)M) plus 2-PAM were greater than those elicited by either drug alone, with the maximum protection afforded being 100%. Combined pretreatment of atropine (10(-5)M) plus physostigmine practically abolished the lethal effects induced by both insecticides. Pretreatment with 2-PAM (10(-6)M) plus physostigmine afforded maximal protection of 100% and 76% on the lethality induced by fonofos and phosphamidon, respectively. The data obtained suggest that the combination of atropine plus 2-PAM or physostigmine and the combined pretreatment of 2-PAM plus physostigmine are effective in the prevention of the lethal effects induced by fonofos and phosphamidon in A. salina larvae.

  8. Effects of microwave power and microwave irradiation time on pretreatment efficiency and characteristics of corn stover using combination of steam explosion and microwave irradiation (SE-MI) pretreatment.

    Science.gov (United States)

    Pang, Feng; Xue, Shulin; Yu, Shengshuan; Zhang, Chao; Li, Bing; Kang, Yong

    2012-08-01

    The effects of microwave power and microwave irradiation time on pretreatment efficiency and characteristics of corn stover were investigated based on a new process named combination of steam explosion and microwave irradiation (SE-MI) pretreatment. Results showed that with microwave power and microwave irradiation time increasing, glucose and xylose that released into hydrolyzate, as well as enzymatic hydrolysis yields and sugar yields of glucose and xylose were all slightly increased after SE-MI pretreatment. The maximum sugar yield was 72.1 g per 100 g glucose and xylose in feedstock, achieved at 540 W microwave power and 5 min microwave irradiation time. XRD analysis showed that the crystallinity of biomass was 15.6-19.9% lower for SE-MI pretreatment with microwave effect than that without microwave effect. However, low microwave power and short microwave irradiation time were favorable for SE-MI pretreatment considering energy consumption.

  9. Biorefining of wheat straw: accounting for the distribution of mineral elements in pretreated biomass by an extended pretreatment – severity equation

    DEFF Research Database (Denmark)

    Le, Duy Michael; Sørensen, Hanne Risbjerg; Knudsen, Niels Ole;

    2014-01-01

    Background: Mineral elements present in lignocellulosic biomass feedstocks may accumulate in biorefinery process streams and cause technological problems, or alternatively can be reaped for value addition. A better understanding of the distribution of minerals in biomass in response to pretreatme...... fiber fractions. A new expanded pretreatment-severity equation is proposed to model and predict mineral composition in pretreated wheat straw biomass...... factors is therefore important in relation to development of new biorefinery processes. The objective of the present study was to examine the levels of mineral elements in pretreated wheat straw in response to systematic variations in the hydrothermal pretreatment parameters (pH, temperature......, and treatment time), and to assess whether it is possible to model mineral levels in the pretreated fiber fraction. Results: Principal component analysis of the wheat straw biomass constituents, including mineral elements, showed that the recovered levels of wheat straw constituents after different hydrothermal...

  10. Pretreatment on Anaerobic Sludge for Enhancement of Biohydrogen Production from Cassava Processing Wastewater

    Directory of Open Access Journals (Sweden)

    Franciele do Carmo Lamaison

    2014-02-01

    Full Text Available Methods for the enrichment of an anaerobic sludge with H2-producing bacteria have been compared by using cassava processing wastewater as substrate.The sludge was submitted to three different pretreatments: 1 heat pretreatment by boiling at 98 °C for 15 min., 2 heat pretreatment followed by sludge washout in a Continuous Stirring Tank Reactor (CSTR operated at a dilution rate (D of 0.021 h-1, and 3 sludge washout as the sole enrichment method. The pretreated sludge and the sludge without pretreatment (control were employed in the seeding of 4 batch bioreactors, in order to verify the volume and composition of the generated biogas. Maximum H2 production rates (Rm from the pretreated sludges, were estimated by the modified Gompertz model. Compared to the control, H2 production was ca. 4 times higher for the sludge submitted to the heat pretreatment only and for the sludge subjected to heat pretreatment combined with washout, and 10 times higher for washout. These findings demonstrated that the use of sludge washout as the sole sludge pretreatment method was the most effective in terms of H2 production, as compared to the heat and to the combined heat and washout pretreatments.

  11. Enhanced biogas production from rice straw with various pretreatment : a review

    Directory of Open Access Journals (Sweden)

    Fahriya Puspita Sari

    2014-04-01

    Full Text Available Rice straw is one of organic material that can be used for sustainable production of bioenergy and biofuels such as biogas (about 50-75% CH4 and 25-50% CO2. Out of all bioconversion technologies for biogas production, anaerobic digestion (AD is a most cost-effective bioconversion technology that has been implemented worldwide for commercial production of electricity, heat, and compressed natural gas (CNG from organic materials. However, the utilization of rice straw for biogas production via anaerobic digestion has not been widely adopted because the complicated structure of the plant cell wall makes it resistant to microbial attack. Pretreatment of recalcitrant rice straw is essential to achieve high biogas yield in the AD process. A number of different pretreatment techniques involving using physical pretreatment (hydrothermal and freeze, chemical pretreatment (sodium carbonate – sodium sulfite, hydrogen peroxide, NMMO, alkaline, and dilute acid and biological pretreatment (fungal pretreatment also combined pretretment (microwave irradiation and chemical approaches have been investigated, but there is no report that systematically compares the performance of these pretreatment methods for application on rice straw for biogas production. This paper reviews the methods that have been studied for pretreatment of rice straw for delignification, reducing sugar, and conversion to biogas. It describes the AD process, structural and compositional properties of rice straw, and various pretreatment techniques, including the pretreatment process, parameters, performance, and advantages vs. drawbacks.

  12. Controllable hydrothermal synthesis of rutile TiO{sub 2} hollow nanorod arrays on TiCl{sub 4} pretreated Ti foil for DSSC application

    Energy Technology Data Exchange (ETDEWEB)

    Xi, Min [Key Laboratory of Renewable Energy, Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou 510640 (China); Zhang, Yulan; Long, Lizhen [Key Laboratory of Renewable Energy, Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou 510640 (China); University of Chinese Academy of Sciences, Beijing 100049 (China); Li, Xinjun, E-mail: lixj@ms.giec.ac.cn [Key Laboratory of Renewable Energy, Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou 510640 (China)

    2014-11-15

    Rutile TiO{sub 2} nanorod arrays (TNRs) were achieved by hydrothermal process on TiCl{sub 4} pretreated Ti foil. Subsequently, TNRs were hydrothermally etched in HCl solution to form hollow TiO{sub 2} nanorod arrays (H-TNRs). The TiCl{sub 4} pretreatment plays key roles in enhancement of Ti foil corrosion resistance ability and crystal nucleation introduction for TNRs growth. TNRs with desired morphology can be obtained by controlling TiCl{sub 4} concentration and the amount of tetrabutyl titanate (TTB) accordingly. TNRs with the length of ∼1.5 μm and diameter of ∼200 nm, obtained on 0.15 M TiCl{sub 4} pretreated Ti foil with 0.6 mL TTB, exhibits relatively higher photocurrent. The increased pore volume of the H-TNRs has contributed to the increased surface area which is benefit for Dye-Sensitized Solar Cells (DSSC) application. And the 180 °C-H-TNRs photoanode obtained from the 0.15-TiCl{sub 4}-TNRs sample demonstrated 128.9% enhancement of photoelectric efficiency of DSSC compared to that of the original TNR photoanode. - Graphical abstract: Rutile hollow TiO{sub 2} nanorod array photoanode obtained from original TiO{sub 2} nanorod array photoanode by hydrothermal etching demonstrates enhanced photoelectric efficiency of DSSC. - Highlights: • TiO{sub 2} nanorods are prepared via hydrothermal process on TiCl{sub 4}-pretreated Ti foil. • Hollow TiO{sub 2} nanorods are obtained by hydrothermal etching of TiO{sub 2} nanorods. • TiCl{sub 4} pretreatment plays a key role in protecting Ti foil from chemical corrosion. • Hollow TiO{sub 2} nanorods photoanode shows enhanced photoelectric efficiency for DSSC.

  13. Physical and chemical characterizations of corn stover and poplar solids resulting from leading pretreatment technologies.

    Science.gov (United States)

    Kumar, Rajeev; Mago, Gaurav; Balan, Venkatesh; Wyman, Charles E

    2009-09-01

    In order to investigate changes in substrate chemical and physical features after pretreatment, several characterizations were performed on untreated (UT) corn stover and poplar and their solids resulting pretreatments by ammonia fiber expansion (AFEX), ammonia recycled percolation (ARP), controlled pH, dilute acid, flowthrough, lime, and SO(2) technologies. In addition to measuring the chemical compositions including acetyl content, physical attributes determined were biomass crystallinity, cellulose degree of polymerization, cellulase adsorption capacity of pretreated solids and enzymatically extracted lignin, copper number, FT-IR responses, scanning electron microscopy (SEM) visualizations, and surface atomic composition by electron spectroscopy of chemical analysis (ESCA). Lime pretreatment removed the most acetyl groups from both corn stover and poplar, while AFEX removed the least. Low pH pretreatments depolymerized cellulose and enhanced biomass crystallinity much more than higher pH approaches. Lime pretreated corn stover solids and flowthrough pretreated poplar solids had the highest cellulase adsorption capacity, while dilute acid pretreated corn stover solids and controlled pH pretreated poplar solids had the least. Furthermore, enzymatically extracted AFEX lignin preparations for both corn stover and poplar had the lowest cellulase adsorption capacity. ESCA results showed that SO(2) pretreated solids had the highest surface O/C ratio for poplar, but for corn stover, the highest value was observed for dilute acid pretreatment with a Parr reactor. Although dependent on pretreatment and substrate, FT-IR data showed that along with changes in cross linking and chemical changes, pretreatments may also decrystallize cellulose and change the ratio of crystalline cellulose polymorphs (Ialpha/Ibeta).

  14. The roles of peroxide protective regulons in protecting Xanthomonas campestris pv. campestris from sodium hypochlorite stress.

    Science.gov (United States)

    Charoenlap, Nisanart; Sornchuer, Phornphan; Piwkam, Anong; Srijaruskul, Kriangsuk; Mongkolsuk, Skorn; Vattanaviboon, Paiboon

    2015-05-01

    The exposure of Xanthomonas campestris pv. campestris to sublethal concentrations of a sodium hypochlorite (NaOCl) solution induced the expression of genes that encode peroxide scavenging enzymes within the OxyR and OhrR regulons. Sensitivity testing in various X. campestris mutants indicated that oxyR, katA, katG, ahpC, and ohr contributed to protection against NaOCl killing. The pretreatment of X. campestris cultures with oxidants, such as hydrogen peroxide (H2O2), t-butyl hydroperoxide, and the superoxide generator menadione, protected the bacteria from lethal concentrations of NaOCl in an OxyR-dependent manner. Treating the bacteria with a low concentration of NaOCl resulted in the adaptive protection from NaOCl killing and also provided cross-protection from H2O2 killing. Taken together, the results suggest that the toxicity of NaOCl is partially mediated by the generation of peroxides and other reactive oxygen species that are removed by primary peroxide scavenging enzymes, such as catalases and AhpC, as a part of an overall strategy that protects the bacteria from the lethal effects of NaOCl.

  15. Kinetic studies of cellulose enzymatic hydrolysis from pretreated corn cob

    Science.gov (United States)

    Stevanie, Jeannie; Kartawiria, Irvan; Abimanyu, Haznan

    2017-01-01

    Successful utilization of corn cob biomass as raw material in bioethanol production is depending on the hydrolysis process where high level of β-cellulose is converted into glucose. Enzymatic hydrolysis is the common process for this purpose. This study is focusing on the evaluation of hydrolysis of pre-treated corn cob using Novozymes Cellic ® C-Tec2 and H-Tec2 enzymes to obtain the optimum reaction condition and its general reaction kinetics. The corn cob used was pretreated using 10% of NaOH solution. Hydrolysis reactions were conducted in 250 ml Erlenmeyer flask for 72 hour using mixture of C-Tec2 and H-Tec2 enzymes at the fixed ratio of 5:1 and glucose concentration were measured using HPLC. Reaction temperature of 40°C and quantity of 0.5 ml enzyme solution per gram substrate gives the highest reaction rate (0.0123 gram of glucose/gram sample.h) with the glucose yield being 0.089 g glucose/ g substrate. Total conversion of cellulose observed was 11.91 %. Corn cob hydrolysis using C-Tec2 and H-Tec2 enzymes also result in xylose (0.0202 g/g substrate), which can also contribute to bioethanol productivity in further fermentation process. The reaction is following zero order kinetics for the first 8 hours and reaches maximum yield within 10 hours; significantly shorter compared to previous studies of cellulosic material hydrolysis that may take up to 72 hour to complete. Prolonging the hydrolysis of pre-treated corn cob more than 24 hour gives no significant increase in glucose conversion and yield. Hydrolysis temperature range of 40°C to 60°C is in accordance with the manufacturer recommendation for the purpose; however the decrease of reaction rate is observable at temperature 50°C or higher.

  16. Enzymatic pretreatment of low-grade oils for biodiesel production.

    Science.gov (United States)

    Nordblad, Mathias; Pedersen, Anders K; Rancke-Madsen, Anders; Woodley, John M

    2016-04-01

    The alkaline process for making biodiesel (fatty acid methyl esters, or FAME) is highly efficient at the transesterification of glycerides. However, its performance is poor when it comes to using oil that contain significant amounts of free fatty acids (FFA). The traditional approach to such feedstocks is to employ acid catalysis, which is slow and requires a large excess of methanol, or to evaporate FFA and convert that in a separate process. An attractive option would be to convert the FFA in oil feedstocks to FAME, before introducing it into the alkaline process. The high selectivity of enzyme catalysis makes it a suitable basis for such a pretreatment process. In this work, we present a characterization of the pretreatment of high-FFA rapeseed oil using immobilized Candida antarctica lipase B (Novozym 435), focused on the impact of initial FFA and methanol concentration. Based on experimental results, we have identified limitations for the process in terms of FFA concentration in the feedstock and make suggestions for process operation. It was found that, using 5% catalyst and 4% methanol at 35°C, the FFA concentration could be reduced to 0.5% within an hour for feedstock containing up to 15% FFA. Further, the reaction was observed to be under kinetic control, in that the biocatalyst converts FFA (and FAME) at a much higher rate than glyceride substrates. There is thus, both a minimum and a maximum reaction time for the process to achieve the desired concentration of FFA. Finally, an assessment of process stability in a continuous packed bed system indicates that as much as 15 m(3) oil could potentially be pretreated by 1 kg of biocatalyst at the given process conditions.

  17. Removal of micropollutants during physicochemical pretreatment of Hospital Wastewater

    Energy Technology Data Exchange (ETDEWEB)

    Suarez, S.; Omil, F.; Lema, J. M.

    2009-07-01

    The fate and occurrence of micro-pollutants, such as pharmaceuticals, hormones or cosmetic ingredients, has attracted an increasing attention in environmental research. The main sources for such compounds in the environment include domestic sewage. hospital effluents and discharges from the pharmaceutical manufacturing industry. The aim of the presented work was to analyse the efficiency of coagulation-flocculation and flotation processes for the pre-treatment of hospital wastewaters, focusing on the removal of 12 Pharmaceutical and Personal Care Products (PPCPs), including musk fragrances, anti-epileptics, tranquillisers, anti-inflammatory drugs, antibiotics and one iodinated contras media. (Author)

  18. Prognotic significance of pretreatment proliferative activity in adult acute leukemia.

    Science.gov (United States)

    Hart, J S; George, S L; Frei, E; Bodey, G P; Nickerson, R C; Freireich, E J

    1977-04-01

    A statistical analysis of the prognostic significance of eight pretreatment variables was undertaken for 71 previously untreated adult patients with acute leukemia seen at M.D. Anderson Hospital over a 5 1/2-year period. None of the patients had received any prior therapy. Nearly all of the patients (68 of the 71) were treated with 4- or 5-day courses of arabinosyl-cytosine alone or in combination with cyclophosphamide, vincristine (oncovin) and prednisone (COAP). The pretreatment variables studied were age at diagnosis, the percent labeling index of the bone marrow leukemic cells, diagnosis, the highest temperature prior to start of treatment, the marrow clot section cellularity and smear differential percent of blasts, percent absolute marrow leukemic cell infiltrate and absolute number of blasts X 10(3)/mm3 in the peripheral blood. Fifty-one patients had acute myeloblastic leukemia (AML) and 20 patients had acute lymphoblastic leukemia (ALL). Using a statistical regression model approach, the only variables found to be of significant prognostic importance with respect to the probability of complete remission for AML patients were the pretreatment percent labeling index, the age of the patient and the highest temperature prior to start of treatment. Unlike AML, the initial percent labeling index did not appear to be of prognostic significance for ALL patients. AML patients with high labeling indices (larger than or equal to 9%) and young patients in general (especially those less than 40 years old) had the best remission rates. With respect to the length of complete remission and survival for all patients, the only important variables were the pretreatment percent labeling index and the age of the patient, respectively. Once in complete remission, an initially high labeling index was an unfavorable sign with respect to length of remission, regardless of the patient's diagnosis. The results of this study are supportive of studies in experimental systems

  19. Bioethanol from lignocellulose - pretreatment, enzyme immobilization and hydrolysis kinetics

    DEFF Research Database (Denmark)

    Tsai, Chien Tai

    , the cost of enzyme is still the bottle neck, re-using the enzyme is apossible way to reduce the input of enzyme in the process. In the point view of engineering, the prediction of enzymatic hydrolysis kinetics under different substrate loading, enzyme combination is usful for process design. Therefore...... following enzymatic hydrolysis of hot water pretreated barley straw by immobilized and free BG. Finally, this is the first time that BG aggregates in a calcium alginate were visualized by confocallaser scanning microscope. The images prove that more BG aggregates were entrapped in the matrix when the enzyme...

  20. BIOCHEMICAL PULPING OF REED PRETREATED BY WHITE ROT FUNGI

    Institute of Scientific and Technical Information of China (English)

    ShiyuFu; AniwarApiz; HuaiyuZhan

    2004-01-01

    The Soda-AQ pulps were made from reed pretreated by white rot fungi Panus conchatus. Cyathus stercoreus and Pleurotus florida respectively. It was found that kappa number decreased and the brightness increased for Soda-AQ pulps from the reed treated by Pleurotus florida and Panus conchatus, but it was reverse for the pulp from reed treated by Cyathus stercoreus. The result indicated that white rot fungi Pleurotus .florida and Panus conchatus were selective to degrade lignin inreed, which were good for biopulping, but Cyathus stercoreus was preferential to degrade cellulose, which was not good for biopulping.

  1. BIOCHEMICAL PULPING OF REED PRETREATED BY WHITE ROT FUNGI

    Institute of Scientific and Technical Information of China (English)

    Shiyu Fu; Aniwar Apiz; Huaiyu Zhan

    2004-01-01

    The Soda-AQ pulps were made from reed pretreated by white rot fungi Panus conchatus,Cyathus stercoreus and Pleurotus florida respectively. It was found that kappa number decreased and the brightness increased for Soda-AQ pulps from the reed treated by Pleurotus florida and Panus conchatus, but it was reverse for the pulp from reed treated by Cyathus stercoreus. The result indicated that white rot fungi Pleurotus florida and Panus conchatus were selective to degrade lignin in reed, which were good for biopulping, but Cyathus stercoreus was preferential to degrade cellulose,which was not good for biopulping.

  2. Electroacupuncture pretreatment attenuates cerebral ischemic injury through α7 nicotinic acetylcholine receptor-mediated inhibition of high-mobility group box 1 release in rats

    Directory of Open Access Journals (Sweden)

    Wang Qiang

    2012-01-01

    of PHA-543,613 on HMGB1 release. Conclusion These data demonstrate that EA pretreatment strongly protects the brain against transient cerebral ischemic injury, and inhibits HMGB1 release through α7nAChR activation in rats. These findings suggest the novel potential for stroke interventions harnessing the anti-inflammatory effects of α7nAChR activation, through acupuncture or pharmacological strategies.

  3. Effects of Temperature Acclimation Pretreatment on the Ultrastructure of Mesophyll Cells in Young Grape Plants (Vitis vinifera L. cv. Jingxiu) Under Cross-Temperature Stresses

    Institute of Scientific and Technical Information of China (English)

    Jun-Huan ZHANG; Wei-Dong HUANG; Yue-Ping LIU; Qiu-Hong PAN

    2005-01-01

    Leaves from annual young grape plants (Vitis vinifera L. cv. Jingxiu) were used as experimentalmaterials. The ultrastructural characteristics of mesophyll cells in chilling-treated plants after heat acclima-tion (HA) and in heat-treated plants after cold acclimation (CA) were observed and compared using trans-mission electron microscopy. The results showed that slight injury appeared in the ultrastructure of meso-phyll cells after either HA (38℃ for 10 h) or CA (8℃ for 2.5 d), but the tolerance to subsequent extremetemperature stress was remarkably improved by HA or CA pretreatment. The increases in membrane perme-ability and malondialdehyde concentration under chilling (0℃) or heat (45℃) stress were markedly inhib-ited by HA or CA pretreatment. The mesophyll cells of plants not pretreated with HA were markedly dam-aged following chilling stress. The chloroplasts appeared irregular in shape, the arrangement of the stromalamellae was disordered, and no starch granules were present. The cristae of the mitochondria were dis-rupted and became empty. The nucleus became irregular in shape and the nuclear membrane was digested.In contrast, the mesophyll cells of HA-pretreated plants maintained an intact ultrastructure under chillingstress. The mesophyll cells of control plants were also severely damaged under heat stress. The chloroplastbecame round in shape, the stroma lamellae became swollen, and the contents of vacuoles formed clumps.In the case of mitochondria of control plants subjected to heat stress, the outer envelope was digested andthe cristae were disrupted and became many small vesicles. Compared with cellular organelles in controlplants, those in CA plant cells always maintained an integrated state during whole heat stress, except for thechloroplasts, which became round in shape after 10 h heat stress. From these data, we suggest that thestability of mesophyll cells under chilling stress can be increased by HA pretreatment. Similarly, CA pretreat-ment

  4. Hepato and reno protective action of Calendula officinalis L. flower extract.

    Science.gov (United States)

    Preethi, Korengath Chandran; Kuttan, Ramadasan

    2009-03-01

    Flower extract of C. officinalis L. was evaluated for its protective effect against CCl4 induced acute hepatotoxicity and cisplatin induced nephrotoxicity. The activities of serum marker enzymes of liver injury like glutamate pyruvate transaminase (SGPT), glutamate oxaloacetate transaminase (SGOT) and alkaline phosphatase (ALP) which were increased by CCl4 injection was found to be significantly reduced by the pretreatment of the flower extract at 100 and 250 mg/kg body weight. The lipid peroxidation in liver, the marker of membrane damage and the total bilirubin content in serum were also found to be at significantly low level in the extract pretreated group, indicating its protective role. The kidney function markers like urea and creatinine were significantly increased in cisplatin treated animals. However, their levels were found to be lowered in the extract pretreated groups (100 and 250 mg/kg body weight). Moreover, cisplatin induced myelosuppression was ameliorated by the extract pretreatment. Treatment with the extract produced enhancement of antioxidant enzymes--superoxide dismutase and catalase and glutathione. Results suggest a protective role of the flower extract of C. officinalis against CCl4 induced acute hepatotoxicity and cisplatin induced nephrotoxicity. Extract has been found to contain several carotenoids of which lutein, zeaxanthin and lycopene predominates. Possible mechanism of action of the flower extract may be due to its antioxidant activity and reduction of oxygen radicals.

  5. Protective effects of pogostone from Pogostemonis Herba against ethanol-induced gastric ulcer in rats.

    Science.gov (United States)

    Chen, Haiming; Liao, Huijun; Liu, Yuhong; Zheng, Yifeng; Wu, Xiaoli; Su, Zuqing; Zhang, Xie; Lai, Zhengquan; Lai, Xiaoping; Lin, Zhi-Xiu; Su, Ziren

    2015-01-01

    We examined the protective effect of pogostone (PO), a chemical constituent isolated from Pogostemonis Herba, on the ethanol-induced gastric ulcer in rats. Administration of PO at doses of 10, 20 and 40 mg/kg body weight prior to ethanol ingestion effectively protected the stomach from ulceration. The gastric lesions were significantly ameliorated by all doses of PO as compared to the vehicle group. Pre-treatment with PO prevented the oxidative damage and the decrease of prostaglandin E2 (PGE2) content. In addition, PO pretreatment markedly increased the mucosa levels of glutathione (GSH), superoxide dismutase (SOD) and catalase (CAT), and decreased gastric malonaldehyde (MDA), relative to the vehicle group. In the mechanistic study, significant elevation of non-protein-sulfhydryl (NP-SH) was observed in the gastric mucosa pretreated by PO. Analysis of serum cytokines indicated that PO pretreatment obviously elevated the decrease of interleukin-10 (IL-10) level, while markedly mitigated the increment of interleukin-6 (IL-6) and tumor necrosis factor alpha (TNF-α) secretions in ethanol-induced rats. Taken together, these results strongly indicate that PO could exert a gastro-protective effect against gastric ulceration, and the underlying mechanism might be associated with the stimulation of PGE2, improvement of antioxidant and anti-inflammatory status, as well as preservation of NP-SH.

  6. Exogenous salicylic acid protects phospholipids against cadmium stress in flax (Linum usitatissimum L.).

    Science.gov (United States)

    Belkadhi, Aïcha; De Haro, Antonio; Obregon, Sara; Chaïbi, Wided; Djebali, Wahbi

    2015-10-01

    Salicylic acid (SA) promotes plant defense responses against toxic metal stresses. The present study addressed the hypothesis that 8-h SA pretreatment, would alter membrane lipids in a way that would protect against Cd toxicity. Flax seeds were pre-soaked for 8h in SA (0, 250 and 1000µM) and then subjected, at seedling stage, to cadmium (Cd) stress. At 100µM CdCl2, significant decreases in the percentages of phosphatidylcholine (PC), phosphatidylglycerol (PG), phosphatidylethanolamine (PE) and monogalactosyldiacylglycerol (MGDG) and changes in their relative fatty acid composition were observed in Cd-treated roots in comparison with controls. However, in roots of 8-h SA pretreated plantlets, results showed that the amounts of PC and PE were significantly higher as compared to non-pretreated plantlets. Additionally, in both lipid classes, the proportion of linolenic acid (18:3) increased upon the pretreatment with SA. This resulted in a significant increase in the fatty acid unsaturation ratio of the root PC and PE classes. As the exogenous application of SA was found to be protective of flax lipid metabolism, the possible mechanisms of protection against Cd stress in flax roots were discussed.

  7. Neuroprotective effects of intravenous transplantation of bone marrow mononuclear cells from 5-fluorouracil pre-treated rats on ischemic stroke.

    Science.gov (United States)

    Li, Y; Mao, W W; Zhang, C G; Wan, L; Jing, C H; Hua, X M; Li, S T; Cheng, J

    2016-03-15

    Our previous findings showed bone marrow mononuclear cells (BMMNCs) from 5- fluorouracil (5-FU) pre-treated rats (named BMRMNCs) had a better therapeutic efficacy in ischemia/reperfusion rats as compared to BMMNCs from untreated rats. This study was undertaken to explore the potential mechanisms underlying the neuroprotective effects of BMRMNCs in middle cerebral artery occlusion (MCAO) rat model. Rats were intravenously pre-treated with 5-FU and BMRMNCs were collected at different time points. The contents of growth factors in the supernatant and CXCR4 expression were detected by ELISA and flow cytometry, respectively. MCAO was introduced to rats, and BMMNCs and BMRMNCs collected at 7 days after 5-FU pre-treatment were independently transplanted via the tail vein 24h later. The neurological function was evaluated before cell transplantation and at 24h, 7d and 14d after cell transplantation. Rats were sacrificed at 14d after cell transplantation, the brains were collected for TTC staining, infarct volume detection, NISSL staining, counting of viable cells in the CA1 region, and observation of transplanted cells. BMRMNCs had elevated expressions of growth factors as well as CXCR4 expression. Our results confirmed the better therapeutic effects of BMRMNCs in MCAO rats, demonstrated by reduction in infarct volume, improvement of neurological function and more viable cells in the hippocampus. In addition, more transplanted cells were found after BMRMNCs transplantation at 7 days and 14 days although there was no marked difference at 14 days. These findings indicate that BMRMNCs transplantation may protect ischemic stroke, at least partially, via increasing the secretion of growth factors and migration to the injured site.

  8. Protection against acetaminophen-induced liver injury by allopurinol is dependent on aldehyde oxidase-mediated liver preconditioning

    Energy Technology Data Exchange (ETDEWEB)

    Williams, C. David; McGill, Mitchell R.; Lebofsky, Margitta; Bajt, Mary Lynn; Jaeschke, Hartmut, E-mail: hjaeschke@kumc.edu

    2014-02-01

    Acetaminophen (APAP) overdose causes severe and occasionally fatal liver injury. Numerous drugs that attenuate APAP toxicity have been described. However these compounds frequently protect by cytochrome P450 inhibition, thereby preventing the initiating step of toxicity. We have previously shown that pretreatment with allopurinol can effectively protect against APAP toxicity, but the mechanism remains unclear. In the current study, C3HeB/FeJ mice were administered allopurinol 18 h or 1 h prior to an APAP overdose. Administration of allopurinol 18 h prior to APAP overdose resulted in an 88% reduction in liver injury (serum ALT) 6 h after APAP; however, 1 h pretreatment offered no protection. APAP-cysteine adducts and glutathione depletion kinetics were similar with or without allopurinol pretreatment. The phosphorylation and mitochondrial translocation of c-jun-N-terminal-kinase (JNK) have been implicated in the progression of APAP toxicity. In our study we showed equivalent early JNK activation (2 h) however late JNK activation (6 h) was attenuated in allopurinol treated mice, which suggests that later JNK activation is more critical for the toxicity. Additional mice were administered oxypurinol (primary metabolite of allopurinol) 18 h or 1 h pre-APAP, but neither treatment protected. This finding implicated an aldehyde oxidase (AO)-mediated metabolism of allopurinol, so mice were treated with hydralazine to inhibit AO prior to allopurinol/APAP administration, which eliminated the protective effects of allopurinol. We evaluated potential targets of AO-mediated preconditioning and found increased hepatic metallothionein 18 h post-allopurinol. These data show metabolism of allopurinol occurring independent of P450 isoenzymes preconditions the liver and renders the animal less susceptible to an APAP overdose. - Highlights: • 18 h allopurinol pretreatment protects against acetaminophen-induced liver injury. • 1 h allopurinol pretreatment does not protect from APAP

  9. Screw extrude steam explosion: a promising pretreatment of corn stover to enhance enzymatic hydrolysis.

    Science.gov (United States)

    Chen, Jingwen; Zhang, Wengui; Zhang, Hongman; Zhang, Qiuxiang; Huang, He

    2014-06-01

    A screw extrude steam explosion (SESE) apparatus was designed and introduced to pretreat corn stover continuously for its following enzymatic hydrolysis. SESE parameters temperature (100, 120, 150°C) and residence time (1, 2, 3min) were investigated. The enzymatic hydrolysis of corn stover pretreated by SESE and steam explosion (SE) process was carried out and analyzed systematically. A serial of analysis methods were established, and the corn stover before/after the pretreatment were characterized by scanning electron microscope (SEM), X-ray Diffraction (XRD) and Thermal Gravity/Derivative Thermal Gravity Analysis (TG/DTG). After treated by SESE pretreatment at the optimum condition (150°C, 2min), the pretreated corn stover exhibited highest enzymatic hydrolysis yield (89%), and rare fermentation inhibitors formed. Characterization results indicated that the highest yield could be attributed to the effective removal of lignin/hemicellulose and destruction of cellulose structure by SESE pretreatment.

  10. Improving methane production from digested manure biofibers by mechanical and thermal alkaline pretreatment

    DEFF Research Database (Denmark)

    Tsapekos, Panagiotis; Kougias, Panagiotis; Frison, A.

    2016-01-01

    Animal manure digestion is associated with limited methane production, due to the high content in fibers, which are hardly degradable lignocellulosic compounds. In this study, different mechanical and thermal alkaline pretreatment methods were applied to partially degradable fibers, separated from...... the effluent stream of biogas reactors. Batch and continuous experiments were conducted to evaluate the efficiency of these pretreatments. In batch experiments, the mechanical pretreatment improved the degradability up to 45%. Even higher efficiency was shown by applying thermal alkaline pretreatments......, enhancing fibers degradability by more than 4-fold. In continuous experiments, the thermal alkaline pretreatment, using 6% NaOH at 55 °C was proven to be the most efficient pretreatment method as the methane production was increased by 26%. The findings demonstrated that the methane production of the biogas...

  11. Comparative data on effects of leading pretreatments and enzyme loadings and formulations on sugar

    Energy Technology Data Exchange (ETDEWEB)

    Wyman, Charles [Univ. of California, Riverside, CA (United States); Balan, Venkatech [Michigan State Univ., East Lansing, MI (United States); Dale, Bruce E. [Michigan State Univ., East Lansing, MI (United States); Elander, Richard [National Renewable Energy Lab. (NREL), Golden, CO (United States); Falls, Matthew [Texas A & M Univ., College Station, TX (United States); Hames, Bonnie [Ceres Corporation, Thousand Oaks, CA (United States); Holtzapple, Mark [Texas A & M Univ., College Station, TX (United States); Ladisch, Michael R. [Purdue Univ., West Lafayette, IN (United States); Lee, Y. Y. [Auburn Univ., AL (United States); Mosier, Nathan [Purdue Univ., West Lafayette, IN (United States); Pallapolu, Venkata R. [Auburn Univ., AL (United States); Shi, Jian [Univ. of California, Riverside, CA (United States); Warner, Ryan E. [Genencor, Palo Alto, CA (United States)

    2011-06-16

    Dilute sulfuric acid (DA), sulfur dioxide (SO2), liquid hot water (LHW), soaking in aqueous ammonia (SAA), ammonia fiber expansion (AFEX), and lime pretreatments were applied to Alamo, Dacotah, and Shawnee switchgrass. Application of the same analytical methods and material balance approaches facil-itated meaningful comparisons of glucose and xylose yields from combined pretreatment and enzymatic hydrolysis. Use of a common supply of cellulase, beta-glucosidase, and xylanase also eased comparisons. All pretreatments enhanced sugar recovery from pretreatment and subsequent enzymatic hydrolysis substantially compared to untreated switchgrass. Adding beta-glucosidase was effective early in enzy-matic hydrolysis while cellobiose levels were high but had limited effect on longer term yields at the enzyme loadings applied. Adding xylanase improved yields most for higher pH pretreatments where more xylan was left in the solids. Harvest time had more impact on performance than switchgrass variety, and microscopy showed changes in different features could impact performance by different pretreatments.

  12. Comparison of Ultrasonic and CO2 Laser Pretreatment Methods on Enzyme Digestibility of Corn Stover

    Directory of Open Access Journals (Sweden)

    Li-Li Zuo

    2012-03-01

    Full Text Available To decrease the cost of bioethanol production, biomass recalcitrance needs to be overcome so that the conversion of biomass to bioethanol becomes more efficient. CO2 laser irradiation can disrupt the lignocellulosic physical structure and reduce the average size of fiber. Analyses with Fourier transform infrared spectroscopy, specific surface area, and the microstructure of corn stover were used to elucidate the enhancement mechanism of the pretreatment process by CO2 laser irradiation. The present work demonstrated that the CO2 laser had potential to enhance the bioconversion efficiency of lignocellulosic waste to renewable bioethanol. The saccharification rate of the CO2 laser pretreatment was significantly higher than ultrasonic pretreatment, and reached 27.75% which was 1.34-fold of that of ultrasonic pretreatment. The results showed the impact of CO2 laser pretreatment on corn stover to be more effective than ultrasonic pretreatment.

  13. Sequential acid-/alkali-pretreatment of empty palm fruit bunch fiber.

    Science.gov (United States)

    Kim, Seonghun; Park, Jang Min; Seo, Jeong-Woo; Kim, Chul Ho

    2012-04-01

    Pretreatment processes are key technologies for generating fermentable sugars based on lignocellulosic biomass. In this study, we developed a novel method for empty palm fruit bunch fiber (EPFBF) using sequential pretreatment with dilute acid and then alkali. Dilute sulfuric acid was used in the first step, which removed 90% of the hemicellulose and 32% of the lignin, but left most of the cellulose under the optimum pretreatment condition. Sodium hydroxide was then applied in the second step, which extracted lignin effectively with a 70% delignification yield, partially disrupting the ordered fibrils of the EPFBF and thus enhancing the enzyme digestibility of the cellulose. The sequentially pretreated biomass consisted of 82% cellulose, less than 1% hemicellulose, and 30% lignin content afterward. The pretreated biomasses morphologically revealed rough, porous, and irregularly ordered surfaces for enhancing enzyme digestibility. These results indicate that the sequentially acid/alkali-pretreated EPFBF could be broadly useful as a novel biomass.

  14. Improving methane production from digested manure biofibers by mechanical and thermal alkaline pretreatment.

    Science.gov (United States)

    Tsapekos, P; Kougias, Panagiotis G; Frison, A; Raga, R; Angelidaki, I

    2016-09-01

    Animal manure digestion is associated with limited methane production, due to the high content in fibers, which are hardly degradable lignocellulosic compounds. In this study, different mechanical and thermal alkaline pretreatment methods were applied to partially degradable fibers, separated from the effluent stream of biogas reactors. Batch and continuous experiments were conducted to evaluate the efficiency of these pretreatments. In batch experiments, the mechanical pretreatment improved the degradability up to 45%. Even higher efficiency was shown by applying thermal alkaline pretreatments, enhancing fibers degradability by more than 4-fold. In continuous experiments, the thermal alkaline pretreatment, using 6% NaOH at 55°C was proven to be the most efficient pretreatment method as the methane production was increased by 26%. The findings demonstrated that the methane production of the biogas plants can be increased by further exploiting the fraction of the digested manure fibers which are discarded in the post-storage tank.

  15. Enhancing solubilisation and methane production kinetic of switchgrass by microwave pretreatment.

    Science.gov (United States)

    Jackowiak, D; Frigon, J C; Ribeiro, T; Pauss, A; Guiot, S

    2011-02-01

    This study investigated the effects of microwave pretreatment of switchgrass in order to enhance its anaerobic digestibility. Response surface analysis was applied to screen the effects of temperature and time of microwave pretreatment on matter solubilisation. The composite design showed that only temperature had a significant effect on solubilisation level. Then the effects of the microwave pretreatment were correlated to the pretreatment temperature. The sCOD/tCOD ratio was equal to 9.4% at 90°C and increased until 13.8% at 180°C. The BMP assays of 42 days showed that microwave pretreatment induced no change on the ultimate volume of methane but had an interesting effect on the reaction kinetic. Indeed, the time required to reach 80% of ultimate volume CH(4) is reduced by 4.5 days at 150°C using the microwave pretreatment.

  16. Pretreatment combining ultrasound and sodium percarbonate under mild conditions for efficient degradation of corn stover.

    Science.gov (United States)

    Nakashima, Kazunori; Ebi, Yuuki; Kubo, Masaki; Shibasaki-Kitakawa, Naomi; Yonemoto, Toshikuni

    2016-03-01

    Ultrasound (US) can be used to disrupt microcrystalline cellulose to give nanofibers via ultrasonic cavitation. Sodium percarbonate (SP), consisting of sodium carbonate and hydrogen peroxide, generates highly reactive radicals, which cause oxidative delignification. Here, we describe a novel pretreatment technique using a combination of US and SP (US-SP) for the efficient saccharification of cellulose and hemicellulose in lignocellulosic corn stover. Although US-SP pretreatment was conducted under mild condition (i.e., at room temperature and atmospheric pressure), the pretreatment greatly increased lignin removal and cellulose digestibility. We also determined the optimum US-SP treatment conditions, such as ultrasonic power output, pretreatment time, pretreatment temperature, and SP concentration for an efficient cellulose saccharification. Moreover, xylose could be effectively recovered from US-SP pretreated biomass without the formation of microbial inhibitor furfural.

  17. Ethanol production from industrial hemp: effect of combined dilute acid/steam pretreatment and economic aspects

    DEFF Research Database (Denmark)

    Gunnarsson, Ingólfur Bragi; Svensson, Sven-Erik; Prade, Thomas;

    2014-01-01

    In the present study, combined steam (140-180 °C) and dilute-acid pre-hydrolysis (0.0-2.0%) were applied to industrial hemp (Cannabis sativa L.), as pretreatment for lignocellulosic bioethanol production. The influence of the pretreatment conditions and cultivation type on the hydrolysis and etha......In the present study, combined steam (140-180 °C) and dilute-acid pre-hydrolysis (0.0-2.0%) were applied to industrial hemp (Cannabis sativa L.), as pretreatment for lignocellulosic bioethanol production. The influence of the pretreatment conditions and cultivation type on the hydrolysis...... pretreated at the optimal conditions showed positive economic results. The type of hemp cultivation (organic or conventional) did not influence significantly the effectiveness of the pretreatment and subsequent enzymatic hydrolysis and ethanol fermentation....

  18. Thermo-chemical pretreatment and enzymatic hydrolysis for enhancing saccharification of catalpa sawdust.

    Science.gov (United States)

    Jin, Shuguang; Zhang, Guangming; Zhang, Panyue; Li, Fan; Fan, Shiyang; Li, Juan

    2016-04-01

    To improve the reducing sugar production from catalpa sawdust, thermo-chemical pretreatments were examined and the chemicals used including NaOH, Ca(OH)2, H2SO4, and HCl. The hemicellulose solubilization and cellulose crystallinity index (CrI) were significantly increased after thermo-alkaline pretreatments, and the thermo-Ca(OH)2 pretreatment showed the best improvement for reducing sugar production comparing to other three pretreatments. The conditions of thermo-Ca(OH)2 pretreatment and enzymatic hydrolysis were systematically optimized. Under the optimal conditions, the reducing sugar yield increased by 1185.7% comparing to the control. This study indicates that the thermo-Ca(OH)2 pretreatment is ideal for the saccharification of catalpa sawdust and that catalpa sawdust is a promising raw material for biofuel.

  19. Pretreatment of Corn Stover Using Supercritical CO2 with Water-Ethanol as Co-solvent

    Institute of Scientific and Technical Information of China (English)

    L(U) Huisheng; REN Miaomiao; ZHANG Minhua; CHEN Ying

    2013-01-01

    Supercritical carbon dioxide,with water-ethanol as co-solvent,was applied to pretreat corn stover to enhance its enzymatic hydrolysis.The efficiency of pretreatment was evaluated by the final reducing sugar yield obtained from the enzymatic hydrolysis of cellulose.Under the operation conditions of pretreatment pressure 15 MPa,temperature 180 ℃ and time 1 h,the optimal sugar yield of 77.8% was obtained.Scanning electron microscopy (SEM) and chemical composition analysis were applied to the pretreated corn stover.The results showed that the surface morphology and microscopic structure of pretreated corn stover were greatly changed.After the pretreatment,the contents of hemicellulose and lignin were reduced obviously.Thus more cellulose was exposed,increasing the sugar yield.

  20. Anaerobic fermentation of biogas liquid pretreated maize straw by rumen microorganisms in vitro.

    Science.gov (United States)

    Jin, Wenyao; Xu, Xiaochen; Gao, Yang; Yang, Fenglin; Wang, Gang

    2014-02-01

    This study intended to investigate the effect of pretreatment of maize straw with biogas liquid on followed fermentation by rumen microorganisms in vitro. The multiple effects including treated time, temperature and dosage of biogas liquid in pretreatment on the followed fermentation performance were analyzed by orthogonal array. The optimum conditions of pretreatment were 9days, 25°C and 50% (v/w) dosage of biogas liquid, which were indicated by the corresponding crystallinity index, dry matter digestibility (DMD) and acetate limiting-step concentration were 57.5%, 73.76% and 1756mg/L, respectively. The ordering sequence of the influential factors for pretreatment was treated time > temperature > dosage of biogas liquid. The results of fermentation showed that the maize straw pretreated by biogas liquid was an efficient and economic pretreatment method of maize straw.