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Sample records for acid modified wheat

  1. Biosorption of methyl blue onto tartaric acid modified wheat bran from aqueous solution

    PubMed Central

    2012-01-01

    Tartaric acid modified wheat bran was utilized as adsorbent to remove methyl blue, a basic dye from aqueous solution. Batch experiments were carried out to study the effect of various experimental parameters such as initial solution pH, contact time, initial dye concentration and adsorbent dosage, on dye adsorption. The results showed that the modification of wheat bran by tartaric acid significantly improved its adsorption capacity, and made this material a suitable adsorbent to remove methyl blue. The adsorption capacity of modified wheat bran was about 1.6 times higher than that of unmodified one. The amount of methyl blue adsorbed was found to vary with initial solution pH, adsorbent dosage, contact time and initial methyl blue concentration. Kinetics study showed that the overall adsorption rate of methyl blue was illustrated by pseudo-second-order kinetic model. The applicability of the Langmuir and Freundlich models for the data was tested. Both models adequately described the experimental data of the biosorption of methyl blue. The maximum adsorption capacity for methyl blue calculated from Langmuir model was 25.18 mg/g. The study has shown the effectiveness of modified wheat bran in the removal of methyl blue, and that it can be considered as an attractive alternative to the more expensive technologies used in wastewater treatment. PMID:23369295

  2. Utilization of extruded linseed to modify fatty composition of intensively-reared lamb meat: effect of associated cereals (wheat vs. corn) and linoleic acid content of the diet.

    PubMed

    Berthelot, V; Bas, P; Schmidely, P

    2010-01-01

    Sixty male lambs were used in two trials to study the efficiency of transfer and elongation of linolenic acid (ALA) in muscle and caudal adipose tissue and to assess factors affecting this process and related changes in fatty acid (FA) profile. In experiment 1, lambs were fed a control diet or extruded linseed (L) diet either with wheat (W, rapid starch) or corn (C, slow starch). In experiment 2, lambs were fed L with "normal" rapeseed, or high-oleic rapeseed, or soybean. In experiment 1, L increased ALA proportion and total n-3 PUFA in muscle and adipose tissue. In adipose tissue but not in muscle, LC lambs had higher proportion of ALA than LW lambs. In experiment 2, increasing linoleic acid (LA) intake increased LA proportion in muscle and adipose tissue but did not modify ALA proportion. Moreover, in muscle, it did not change the desaturation and elongation processes of ALA to long-chain n-3 PUFA.

  3. Agronomic Performance of Low Phytic Acid Wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Low phytic acid (LPA) genotypes of wheat are one approach to improving the nutritional quality of wheat by reducing the concentration of phytic acid in the aleurone layer, thus reducing the chelation of nutritionally important minerals and improving the bioavailability of phosphorus. Field studies ...

  4. New Uses for Wheat and Modified Wheat Products

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Hard wheat from the Great Plains historically has been used as a source of flour for the production of leavened bakery products. However, potentially applications of wheat in both new markets and new products has necessitated the need to develop wheats with novel processing attributes. The most lo...

  5. Cold plasma: A new technology to modify wheat flour functionality.

    PubMed

    Bahrami, Niloufar; Bayliss, Danny; Chope, Gemma; Penson, Simon; Perehinec, Tania; Fisk, Ian D

    2016-07-01

    Atmospheric pressure cold plasma has the potential to modify biological chemistry and modulate physical surface properties. Wheat flour was treated by low levels of cold plasma (air, 15V and 20V) for 60 or 120s. There was no change in the total aerobic bacterial count or total mould count as a result of treatment. Treatment did not impact the concentration of total non-starch lipids, or non-polar and glycolipids. However, treatment did reduce total free fatty acids and phospholipids and was dose dependent. Oxidation markers (hydroperoxide value and head space n-hexanal) increased with treatment time and voltage, which confirmed the acceleration of lipid oxidation. Total proteins were not significantly influenced by treatment although there was a trend towards higher molecular weight fractions which indicated protein oxidation and treated flour did produce a stronger dough. This study confirms the potential of cold plasma as a tool to modify flour functionality. PMID:26920291

  6. Gene Flow in Genetically Modified Wheat

    PubMed Central

    Rieben, Silvan; Kalinina, Olena; Schmid, Bernhard; Zeller, Simon L.

    2011-01-01

    Understanding gene flow in genetically modified (GM) crops is critical to answering questions regarding risk-assessment and the coexistence of GM and non-GM crops. In two field experiments, we tested whether rates of cross-pollination differed between GM and non-GM lines of the predominantly self-pollinating wheat Triticum aestivum. In the first experiment, outcrossing was studied within the field by planting “phytometers” of one line into stands of another line. In the second experiment, outcrossing was studied over distances of 0.5–2.5 m from a central patch of pollen donors to adjacent patches of pollen recipients. Cross-pollination and outcrossing was detected when offspring of a pollen recipient without a particular transgene contained this transgene in heterozygous condition. The GM lines had been produced from the varieties Bobwhite or Frisal and contained Pm3b or chitinase/glucanase transgenes, respectively, in homozygous condition. These transgenes increase plant resistance against pathogenic fungi. Although the overall outcrossing rate in the first experiment was only 3.4%, Bobwhite GM lines containing the Pm3b transgene were six times more likely than non-GM control lines to produce outcrossed offspring. There was additional variation in outcrossing rate among the four GM-lines, presumably due to the different transgene insertion events. Among the pollen donors, the Frisal GM line expressing a chitinase transgene caused more outcrossing than the GM line expressing both a chitinase and a glucanase transgene. In the second experiment, outcrossing after cross-pollination declined from 0.7–0.03% over the test distances of 0.5–2.5 m. Our results suggest that pollen-mediated gene flow between GM and non-GM wheat might only be a concern if it occurs within fields, e.g. due to seed contamination. Methodologically our study demonstrates that outcrossing rates between transgenic and other lines within crops can be assessed using a phytometer approach and

  7. Cold plasma: A new technology to modify wheat flour functionality

    PubMed Central

    Bahrami, Niloufar; Bayliss, Danny; Chope, Gemma; Penson, Simon; Perehinec, Tania; Fisk, Ian D.

    2016-01-01

    Atmospheric pressure cold plasma has the potential to modify biological chemistry and modulate physical surface properties. Wheat flour was treated by low levels of cold plasma (air, 15 V and 20 V) for 60 or 120 s. There was no change in the total aerobic bacterial count or total mould count as a result of treatment. Treatment did not impact the concentration of total non-starch lipids, or non-polar and glycolipids. However, treatment did reduce total free fatty acids and phospholipids and was dose dependent. Oxidation markers (hydroperoxide value and head space n-hexanal) increased with treatment time and voltage, which confirmed the acceleration of lipid oxidation. Total proteins were not significantly influenced by treatment although there was a trend towards higher molecular weight fractions which indicated protein oxidation and treated flour did produce a stronger dough. This study confirms the potential of cold plasma as a tool to modify flour functionality. PMID:26920291

  8. Aphid–parasitoid community structure on genetically modified wheat

    PubMed Central

    von Burg, Simone; van Veen, Frank J. F.; Álvarez-Alfageme, Fernando; Romeis, Jörg

    2011-01-01

    Since the introduction of genetically modified (GM) plants, one of the main concerns has been their potential effect on non-target insects. Many studies have looked at GM plant effects on single non-target herbivore species or on simple herbivore–natural enemy food chains. Agro-ecosystems, however, are characterized by numerous insect species which are involved in complex interactions, forming food webs. In this study, we looked at transgenic disease-resistant wheat (Triticum aestivum) and its effect on aphid–parasitoid food webs. We hypothesized that the GM of the wheat lines directly or indirectly affect aphids and that these effects cascade up to change the structure of the associated food webs. Over 2 years, we studied different experimental wheat lines under semi-field conditions. We constructed quantitative food webs to compare their properties on GM lines with the properties on corresponding non-transgenic controls. We found significant effects of the different wheat lines on insect community structure up to the fourth trophic level. However, the observed effects were inconsistent between study years and the variation between wheat varieties was as big as between GM plants and their controls. This suggests that the impact of our powdery mildew-resistant GM wheat plants on food web structure may be negligible and potential ecological effects on non-target insects limited. PMID:21247941

  9. Development of taxon-specific sequences of common wheat for the detection of genetically modified wheat.

    PubMed

    Iida, Mayu; Yamashiro, Satomi; Yamakawa, Hirohito; Hayakawa, Katsuyuki; Kuribara, Hideo; Kodama, Takashi; Furui, Satoshi; Akiyama, Hiroshi; Maitani, Tamio; Hino, Akihiro

    2005-08-10

    Qualitative and quantitative Polymerase Chain Reaction (PCR) systems aimed at the specific detection and quantification of common wheat DNA are described. Many countries have issued regulations to label foods that include genetically modified organisms (GMOs). PCR technology is widely recognized as a reliable and useful technique for the qualitative and quantitative detection of GMOs. Detection methods are needed to amplify a target GM gene, and the amplified results should be compared with those of the corresponding taxon-specific reference gene to obtain reliable results. This paper describes the development of a specific DNA sequence in the waxy-D1 gene for common wheat (Triticum aestivum L.) and the design of a specific primer pair and TaqMan probe on the waxy-D1 gene for PCR analysis. The primers amplified a product (Wx012) of 102 bp. It is indicated that the Wx012 DNA sequence is specific to common wheat, showing homogeneity in qualitative PCR results and very similar quantification accuracy along 19 distantly related common wheat varieties. In Southern blot and real-time PCR analyses, this sequence showed either a single or a low number of copy genes. In addition, by qualitative and quantitative PCR using wx012 primers and a wx012-T probe, the limits of detection of the common wheat genome were found to be about 15 copies, and the reproducibility was reliable. In consequence, the PCR system using wx012 primers and wx012-T probe is considered to be suitable for use as a common wheat-specific taxon-specific reference gene in DNA analyses, including GMO tests.

  10. Modification of wheat gluten with citric acid to produce superabsorbent materials

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Wheat gluten was reacted with citric acid to produce natural superabsorbent materials able to absorb up to 78 times its weight in water. The properties of the modified gluten samples were characterized using Fourier Transform Infra-red (FTIR) spectroscopy, thermogravimetric analysis, and water uptak...

  11. Kinetics of cadmium, chromium, and lead sorption onto chemically modified sugarcane bagasse and wheat straw.

    PubMed

    Mahmood-ul-Hassan, M; Suthar, V; Rafique, E; Ahmad, R; Yasin, M

    2015-07-01

    In this study, cadmium (Cd), chromium (Cr), and lead (Pb) adsorption potential of unmodified and modified sugarcane bagasse and ground wheat straw was explored from aqueous solution through batch equilibrium technique. Both the materials were chemically modified by treating with sodium hydroxide (NaOH) alone and in combination with nitric acid (HNO3) and sulfuric acid (H2SO4). Two kinetic models, pseudo-first order and pseudo-second order were used to follow the adsorption process and reaction fallowed the later model. The Pb removal by both the materials was highest and followed by Cr and Cd. The chemical treatment invariably increased the adsorption capacity and NaOH treatment proved more effective than others. Langmuir maximum sorption capacity (q m) of Pb was utmost (12.8-23.3 mg/g of sugarcane bagasse, 14.5-22.4 mg/g of wheat straw) and of Cd was least (1.5-2.2 mg/g of sugarcane bagasse, 2.5-3.8 mg/g of wheat straw). The q m was in the order of Pb > Cr > Cd for all the three adsorbents. Results demonstrate that agricultural waste materials used in this study could be used to remediate the heavy metal-polluted water.

  12. Assessment of the nutritional values of genetically modified wheat, corn, and tomato crops.

    PubMed

    Venneria, Eugenia; Fanasca, Simone; Monastra, Giovanni; Finotti, Enrico; Ambra, Roberto; Azzini, Elena; Durazzo, Alessandra; Foddai, Maria Stella; Maiani, Giuseppe

    2008-10-01

    The genetic modification in fruit and vegetables could lead to changes in metabolic pathways and, therefore, to the variation of the molecular pattern, with particular attention to antioxidant compounds not well-described in the literature. The aim of the present study was to compare the quality composition of transgenic wheat ( Triticum durum L.), corn ( Zea mays L.), and tomato ( Lycopersicum esculentum Mill.) to the nontransgenic control with a similar genetic background. In the first experiment, Ofanto wheat cultivar containing the tobacco rab1 gene and nontransgenic Ofanto were used. The second experiment compared two transgenic lines of corn containing Bacillus thuringiensis "Cry toxin" gene (PR33P67 and Pegaso Bt) to their nontransgenic forms. The third experiment was conducted on transgenic tomato ( Lycopersicum esculentum Mill.) containing the Agrobacterium rhizogenes rolD gene and its nontransgenic control (cv. Tondino). Conventional and genetically modified crops were compared in terms of fatty acids content, unsaponifiable fraction of antioxidants, total phenols, polyphenols, carotenoids, vitamin C, total antioxidant activity, and mineral composition. No significant differences were observed for qualitative traits analyzed in wheat and corn samples. In tomato samples, the total antioxidant activity (TAA), measured by FRAP assay, and the naringenin content showed a lower value in genetically modified organism (GMO) samples (0.35 mmol of Fe (2+) 100 g (-1) and 2.82 mg 100 g (-1), respectively), in comparison to its nontransgenic control (0.41 mmol of Fe (2+) 100 g (-1) and 4.17 mg 100 g (-1), respectively). On the basis of the principle of substantial equivalence, as articulated by the World Health Organization, the Organization for Economic Cooperation and Development, and the United Nations Food and Agriculture Organization, these data support the conclusion that GM events are nutritionally similar to conventional varieties of wheat, corn, and tomato on

  13. Assessment of the nutritional values of genetically modified wheat, corn, and tomato crops.

    PubMed

    Venneria, Eugenia; Fanasca, Simone; Monastra, Giovanni; Finotti, Enrico; Ambra, Roberto; Azzini, Elena; Durazzo, Alessandra; Foddai, Maria Stella; Maiani, Giuseppe

    2008-10-01

    The genetic modification in fruit and vegetables could lead to changes in metabolic pathways and, therefore, to the variation of the molecular pattern, with particular attention to antioxidant compounds not well-described in the literature. The aim of the present study was to compare the quality composition of transgenic wheat ( Triticum durum L.), corn ( Zea mays L.), and tomato ( Lycopersicum esculentum Mill.) to the nontransgenic control with a similar genetic background. In the first experiment, Ofanto wheat cultivar containing the tobacco rab1 gene and nontransgenic Ofanto were used. The second experiment compared two transgenic lines of corn containing Bacillus thuringiensis "Cry toxin" gene (PR33P67 and Pegaso Bt) to their nontransgenic forms. The third experiment was conducted on transgenic tomato ( Lycopersicum esculentum Mill.) containing the Agrobacterium rhizogenes rolD gene and its nontransgenic control (cv. Tondino). Conventional and genetically modified crops were compared in terms of fatty acids content, unsaponifiable fraction of antioxidants, total phenols, polyphenols, carotenoids, vitamin C, total antioxidant activity, and mineral composition. No significant differences were observed for qualitative traits analyzed in wheat and corn samples. In tomato samples, the total antioxidant activity (TAA), measured by FRAP assay, and the naringenin content showed a lower value in genetically modified organism (GMO) samples (0.35 mmol of Fe (2+) 100 g (-1) and 2.82 mg 100 g (-1), respectively), in comparison to its nontransgenic control (0.41 mmol of Fe (2+) 100 g (-1) and 4.17 mg 100 g (-1), respectively). On the basis of the principle of substantial equivalence, as articulated by the World Health Organization, the Organization for Economic Cooperation and Development, and the United Nations Food and Agriculture Organization, these data support the conclusion that GM events are nutritionally similar to conventional varieties of wheat, corn, and tomato on

  14. Stress-induced accumulation of wheat germ agglutinin and abscisic acid in roots of wheat seedlings

    SciTech Connect

    Cammue, B.P.A.; Broekaert, W.F.; Kellens, J.T.C.; Peumans, W.J. ); Raikhel, N.V. )

    1989-12-01

    Wheat germ agglutinin (WGA) levels in roots of 2-day-old wheat seedlings increased up to three-fold when stressed by air-drying. Similar results were obtained when seedling roots were incubated either in 0.5 molar mannitol or 180 grams per liter polyethylene glycol 6,000, with a peak level of WGA after 5 hours of stress. Longer periods of osmotic treatment resulted in a gradual decline of WGA in the roots. Since excised wheat roots incorporate more ({sup 35}S)cysteine into WGA under stress conditions, the observed increase of lectin levels is due to de novo synthesis. Measurement of abscisic acid (ABA) levels in roots of control and stressed seedlings indicated a 10-fold increase upon air-drying. Similarly, a five- and seven-fold increase of ABA content of seedling roots was found after 2 hours of osmotic stress by polyethylene glycol 6,000 and mannitol, respectively. Finally, the stress-induced increase of WGA in wheat roots could be inhibited by growing seedlings in the presence of fluridone, an inhibitor of ABA synthesis. These results indicate that roots of water-stressed wheat seedlings (a) contain more WGA as a result of an increased de novo synthesis of this lectin, and (b) exhibit higher ABA levels. The stress-induced increase of lectin accumulation seems to be under control of ABA.

  15. Changes of nucleic acids of wheat seedlings under spaceflight conditions

    NASA Technical Reports Server (NTRS)

    Sytnyk, K. M.; Musatenko, L. I.

    1983-01-01

    The effects of space flight on the growth of wheat seedlings and their nucleic acid content were studied. It was shown that both space and ground seedlings have almost the same appearance, dry weight and nucleic acid content in the root, coleoptile and leaves. The only difference found is in the RNA and DNA content, which is twice as much in the ground seedling apices as in the space-grown seedlings.

  16. Influence of gelatinization on the extraction of phenolic acids from wheat fractions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The effect of gelatinization on the analysis of phenolic acids from wheat bran, whole-wheat, and refined flour samples was investigated using two extraction procedures, namely, ultrasonic (UAE) and microwave (MAE). The total phenolic acid (TPA) concentration quantity in wheat bran (2711-2913 µg/g) w...

  17. Modeling the continuous lactic acid production process from wheat flour.

    PubMed

    Gonzalez, Karen; Tebbani, Sihem; Lopes, Filipa; Thorigné, Aurore; Givry, Sébastien; Dumur, Didier; Pareau, Dominique

    2016-01-01

    A kinetic model of the simultaneous saccharification, protein hydrolysis, and fermentation (SSPHF) process for lactic acid production from wheat flour has been developed. The model describes the bacterial growth, substrate consumption, lactic acid production, and maltose hydrolysis. The model was fitted and validated with data from SSPHF experiments obtained under different dilution rates. The results of the model are in good agreement with the experimental data. Steady state concentrations of biomass, lactic acid, glucose, and maltose as function of the dilution rate were predicted by the model. This steady state analysis is further useful to determine the operating conditions that maximize lactic acid productivity.

  18. Nanoparticles modified with multiple organic acids

    NASA Technical Reports Server (NTRS)

    Cook, Ronald Lee (Inventor); Luebben, Silvia DeVito (Inventor); Myers, Andrew William (Inventor); Smith, Bryan Matthew (Inventor); Elliott, Brian John (Inventor); Kreutzer, Cory (Inventor); Wilson, Carolina (Inventor); Meiser, Manfred (Inventor)

    2007-01-01

    Surface-modified nanoparticles of boehmite, and methods for preparing the same. Aluminum oxyhydroxide nanoparticles are surface modified by reaction with selected amounts of organic acids. In particular, the nanoparticle surface is modified by reactions with two or more different carboxylic acids, at least one of which is an organic carboxylic acid. The product is a surface modified boehmite nanoparticle that has an inorganic aluminum oxyhydroxide core, or part aluminum oxyhydroxide core and a surface-bonded organic shell. Organic carboxylic acids of this invention contain at least one carboxylic acid group and one carbon-hydrogen bond. One embodiment of this invention provides boehmite nanoparticles that have been surface modified with two or more acids one of which additional carries at least one reactive functional group. Another embodiment of this invention provides boehmite nanoparticles that have been surface modified with multiple acids one of which has molecular weight or average molecular weight greater than or equal to 500 Daltons. Yet, another embodiment of this invention provides boehmite nanoparticles that are surface modified with two or more acids one of which is hydrophobic in nature and has solubility in water of less than 15 by weight. The products of the methods of this invention have specific useful properties when used in mixture with liquids, as filler in solids, or as stand-alone entities.

  19. Nanoparticles modified with multiple organic acids

    DOEpatents

    Cook, Ronald Lee; Luebben, Silvia DeVito; Myers, Andrew William; Smith, Bryan Matthew; Elliott, Brian John; Kreutzer, Cory; Wilson, Carolina; Meiser, Manfred

    2007-07-17

    Surface-modified nanoparticles of boehmite, and methods for preparing the same. Aluminum oxyhydroxide nanoparticles are surface modified by reaction with selected amounts of organic acids. In particular, the nanoparticle surface is modified by reactions with two or more different carboxylic acids, at least one of which is an organic carboxylic acid. The product is a surface modified boehmite nanoparticle that has an inorganic aluminum oxyhydroxide core, or part aluminum oxyhydroxide core and a surface-bonded organic shell. Organic carboxylic acids of this invention contain at least one carboxylic acid group and one carbon-hydrogen bond. One embodiment of this invention provides boehmite nanoparticles that have been surface modified with two or more acids one of which additional carries at least one reactive functional group. Another embodiment of this invention provides boehmite nanoparticles that have been surface modified with multiple acids one of which has molecular weight or average molecular weight greater than or equal to 500 Daltons. Yet, another embodiment of this invention provides boehmite nanoparticles that are surface modified with two or more acids one of which is hydrophobic in nature and has solubility in water of less than 15 by weight. The products of the methods of this invention have specific useful properties when used in mixture with liquids, as filler in solids, or as stand-alone entities.

  20. Accumulation of hydroxycinnamic acid amides in winter wheat under snow.

    PubMed

    Jin, Shigeki; Yoshida, Midori; Nakajima, Takashi; Murai, Akio

    2003-06-01

    It was found that the content of antifungal compounds p-coumaroylagmatine [1-(trans-4'-hydroxycinnamoylamino)-4-guanidinobutane] and p-coumaroyl-3-hydroxyagmatine [1-(trans-4'-hydroxycinnamoylamino)-3-hydroxy-4-guanidinobutane] in the crown of winter wheat (Triticum aestivum L. cv Chihokukomugi) significantly increased under snow cover. This finding suggests that the accumulation of these hydroxycinnamic acid amides was caused by winter stress and related to protecting the plant against snow mold under snow cover.

  1. Enlarged processing window of plasticized wheat gluten using salicylic acid.

    PubMed

    Ullsten, N Henrik; Gällstedt, Mikael; Johansson, Eva; Gräslund, Astrid; Hedenqvist, Mikael S

    2006-03-01

    The temperature window for the extrusion of glycerol-plasticized wheat gluten was increased by the use of salicylic acid, a known scorch retarder and radical scavenger. It was possible to extrude 30 wt % glycerol-wheat gluten films with a die-head temperature as high as 135 degrees C, rather than 95 degrees C, by incorporating only 1 wt % salicylic acid. Small effects of shear-induced heating during extrusion at the higher temperatures suggested that the acid acted as a lubricant and viscosity reducer. The latter was suggested to originate primarily from the salicylic-acid-induced reduction in the degree of protein aggregation/cross-linking, as indicated by size-exclusion high-performance liquid chromatography and chemiluminescence. Electron paramagnetic resonance spectroscopy on extruded films indicated that the beneficial effect of salicylic acid was due to its radical scavenging effect. Tensile tests on extrudates revealed that the materials produced at the substantially higher processing temperature were still ductile. The complex shear modulus increased more slowly with increasing salicylic acid content above 110-120 degrees C, indicating that the aggregation/cross-linking rate was slower with salicylic acid, that is, that it did have a scorch-retarding effect, besides yielding a lower final degree/complexity of aggregation.

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

    PubMed Central

    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) glucose benefits from improved enzymatic digestibility of wheat straw solids; (2) xylose benefits from the solubilization of xylan to the liquid phase during the pretreatment; (3) maleic acid replenishment costs; (4) neutralization costs of pretreated material; (5) costs due to furfural production; and (6) heating costs of the input materials. For each response factor, experimental data were fitted mathematically. After data translation to €/Mg dry straw, determining the relative contribution of each response factor, an economic optimization was calculated within the limits of the design variables. Results When costs are disregarded, an almost complete glucan conversion to glucose can be reached (90% from solids, 7%-10% in liquid), after enzymatic hydrolysis. During the pretreatment, up to 90% of all xylan is converted to monomeric xylose. Taking cost factors into account, the optimal process conditions are: 50 min at 170°C, with 46 mM maleic acid, resulting in a yield of 65 €/Mg (megagram = metric ton) dry straw, consisting of 68 €/Mg glucose benefits (from solids: 85% of all glucan), 17 €/Mg xylose benefits (from liquid: 80% of all xylan), 17 €/Mg maleic acid costs, 2.0 €/Mg heating costs and 0.68 €/Mg NaOH costs. In all but the most severe of the studied conditions, furfural formation was so limited that associated costs are considered negligible. Conclusions After the dilute maleic acid pretreatment and subsequent enzymatic hydrolysis, almost complete conversion of wheat straw glucan and xylan is possible. Taking maleic acid replenishment, heating, neutralization and furfural formation into account, the optimum in the dilute maleic acid pretreatment of

  3. Cytokinin producing bacteria stimulate amino acid deposition by wheat roots.

    PubMed

    Kudoyarova, Guzel R; Melentiev, Alexander I; Martynenko, Elena V; Timergalina, Leila N; Arkhipova, Tatiana N; Shendel, Galina V; Kuz'mina, Ludmila Yu; Dodd, Ian C; Veselov, Stanislav Yu

    2014-10-01

    Phytohormone production is one mechanism by which rhizobacteria can stimulate plant growth, but it is not clear whether the bacteria gain from this mechanism. The hypothesis that microbial-derived cytokinin phytohormones stimulate root exudation of amino acids was tested. The rhizosphere of wheat plants was drenched with the synthetic cytokinin trans-zeatin or inoculated with Bacillus subtilis IB-22 (which produces zeatin type cytokinins) or B. subtilis IB-21 (which failed to accumulate cytokinins). Growing plants in a split root system allowed spatial separation of zeatin application or rhizobacterial inoculation to one compartment and analyses of amino acid release from roots (rhizodeposition) into the other compartment (without either microbial inoculation or treatment with exogenous hormone). Supplying B. subtilis IB-22 or zeatin to either the whole root system or half of the roots increased concentrations of amino acids in the soil solution although the magnitude of the increase was greater when whole roots were treated. There was some similarity in amino acid concentrations induced by either bacterial or zeatin treatment. Thus B. subtilis IB-22 increased amino acid rhizodeposition, likely due to its ability to produce cytokinins. Furthermore, B. subtilis strain IB-21, which failed to accumulate cytokinins in culture media, did not significantly affect amino acid concentrations in the wheat rhizosphere. The ability of rhizobacteria to produce cytokinins and thereby stimulate rhizodeposition may be important in enhancing rhizobacterial colonization of the rhizoplane.

  4. Biohydrogen and carboxylic acids production from wheat straw hydrolysate.

    PubMed

    Chandolias, Konstantinos; Pardaev, Sindor; Taherzadeh, Mohammad J

    2016-09-01

    Hydrolyzed wheat straw was converted into carboxylic acids and biohydrogen using digesting bacteria. The fermentations were carried out using both free and membrane-encased thermophilic bacteria (55°C) at various OLRs (4.42-17.95g COD/L.d), in semi-continuous conditions using one or two bioreactors in a series. The highest production of biohydrogen and acetic acid was achieved at an OLR of 4.42g COD/L.d, whilst the highest lactic acid production occurred at an OLR of 9.33g COD/L.d. Furthermore, the bioreactor with both free and membrane-encased cells produced 60% more lactic acid compared to the conventional, free-cell bioreactor. In addition, an increase of 121% and 100% in the production of acetic and isobutyric acid, respectively, was achieved in the 2nd-stage bioreactor compared to the 1st-stage bioreactor.

  5. [Effect of acid rain on seed germination of rice, wheat and rape].

    PubMed

    Zeng, Qing-ling; Huang, Xiao-hua; Zhou, Qing

    2005-01-01

    Rice, wheat and rape seeds were treated with simulated acid rain at pH 2.0, 2.5, 3.0, 3.5, 4.0 and 5.0 levels for 7 days in order to understand the effects of acid rain on seed germination of various acid-fast plant. The germination test showed that seed germination was absolutely inhibited at pH 2.0 for three species. Rice and wheat seeds germinated abnormally at pH 2.5. WhenpH values above 3.0, percentage germination, germination energy, germination index, vigor index of rice, wheat and rape seeds increased in relation with decreased acidity levels. In contrast, the percentage of abnormal germination of rice and wheat decreased. The experiment data about physiological aspect demonstrated that water absorption rate, respiratory rate and storage reserve transformation rate of rice, wheat and rape seeds also increased with increased pH values. The storage loss of rice and wheat increased with increased pH values but that of rape decreased. Inhibition index of shoot and root length of three kinds of seeds decreased in relation with increased pH values. The amplitude difference of index of rice was lower than that of wheat, and wheat was lower than that of rape. The experiment data showed that rice had stronger fastness than wheat and rape, wheat had stronger fastness than rape under acid rain stress.

  6. Effect of acetic acid on physical properties of pregelatinized wheat and corn starch gels.

    PubMed

    Majzoobi, Mahsa; Kaveh, Zahra; Farahnaky, Asgar

    2016-04-01

    Pregelatinized starches are physically modified starches with ability to absorb water and increase viscosity at ambient temperature. The main purpose of this study was to determine how different concentrations of acetic acid (0, 500, 1000, 10,000 mg/kg) can affect functional properties of pregelatinized wheat and corn starches (PGWS and PGCS, respectively) produced by a twin drum drier. With increasing acetic acid following changes occurred for both samples; cold water solubility (at 25 °C) increased, water absorption and apparent cold water viscosity (at 25 °C) reduced, the smooth surface of the starch particles converted to an uneven surface as confirmed by scanning electron microscopy, cohesiveness, consistency and turbidity of the starch gels reduced while their syneresis increased. It was found that in presence of acetic acid, PGWS resulted in higher water absorption and apparent cold water viscosity and produced more cohesive and turbid gels with less syneresis compared to PGCS. PMID:26593546

  7. Effect of acetic acid on physical properties of pregelatinized wheat and corn starch gels.

    PubMed

    Majzoobi, Mahsa; Kaveh, Zahra; Farahnaky, Asgar

    2016-04-01

    Pregelatinized starches are physically modified starches with ability to absorb water and increase viscosity at ambient temperature. The main purpose of this study was to determine how different concentrations of acetic acid (0, 500, 1000, 10,000 mg/kg) can affect functional properties of pregelatinized wheat and corn starches (PGWS and PGCS, respectively) produced by a twin drum drier. With increasing acetic acid following changes occurred for both samples; cold water solubility (at 25 °C) increased, water absorption and apparent cold water viscosity (at 25 °C) reduced, the smooth surface of the starch particles converted to an uneven surface as confirmed by scanning electron microscopy, cohesiveness, consistency and turbidity of the starch gels reduced while their syneresis increased. It was found that in presence of acetic acid, PGWS resulted in higher water absorption and apparent cold water viscosity and produced more cohesive and turbid gels with less syneresis compared to PGCS.

  8. Wheat rolls fortified with microencapsulated L-5-methyltetrahydrofolic acid or equimolar folic acid increase blood folate concentrations to a similar extent in healthy men and women.

    PubMed

    Green, Timothy J; Liu, Yazheng; Dadgar, Samira; Li, Wangyang; Böhni, Ruth; Kitts, David D

    2013-06-01

    Mandatory folic acid fortification of grains such as wheat flour has been introduced in several countries to reduce the incidence of neural tube defects. There are concerns, however, that folic acid could mask the hematologic signs of vitamin B-12 deficiency and lead to other adverse health outcomes in the population. Calcium L-5-methyltetrahydrofolic acid (L-5-MTHF), a synthetic form of reduced folate, should not mask vitamin B-12 deficiency and may be safer than folic acid. Unfortunately, L-5-MTHF is not stable in most food matrices such as bread. Microencapsulation of L-5-MTHF with sodium ascorbate and a modified starch is effective at preventing loss of the vitamin during baking and storage. Our aim was to assess the efficacy of wheat rolls fortified with microencapsulated L-5-MTHF or equimolar folic acid compared with wheat rolls containing no added folate (placebo) at increasing blood folate concentrations during 16 wk. Healthy men and women aged 18-45 y (n = 45) were randomly assigned to consume wheat rolls that contained L-5-MTHF (452 μg/d), the molar equivalent of folic acid (400 μg/d), or placebo. At 16 wk, the mean (95% CI) erythrocyte folate was 0.48 (0.27, 0.71) and 0.37 (0.17, 0.57) μmol/L higher in the L-5-MTHF (P < 0.001) and folic acid wheat roll (P = 0.001) groups, respectively, than in the placebo group. Likewise, the mean plasma folate was 23 (12, 34) and 23 (12, 34) nmol/L higher in the L-5-MTHF (P < 0.001) and folic acid wheat roll (P < 0.001) groups, respectively, than in the placebo group. There were no significant differences in blood folate concentrations between the L-5-MTHF and folic acid wheat roll groups. Both microencapsulated L-5-MTHF and folic acid-fortified wheat rolls increased blood folate concentrations compared with placebo.

  9. [Effect of wheat and faba bean intercropping on root exudation of low molecular weight organic acids].

    PubMed

    Xiao, Jing-Xiu; Zheng, Yi; Tang, Li

    2014-06-01

    Pot experiment of wheat and faba bean intercropping was conducted and exudates from wheat and faba bean roots were collected at different growth stages. Low molecular weight organic acids (OA) in root exudates were examined by HPLC. The results showed that wheat and faba bean intercropping significantly increased the total amounts of OA exuded by roots. At tillering (57 d), booting (120 d) and filling stages (142 d), intercropping increased the total amounts of OA in wheat root exudates by 155%, 35.6% and 92.6% respectively, in comparison with that of monoculture wheat (MW). At branching (57 d) and filling stages (142 d), intercropping increased the total amounts of OA in faba bean root exudates by 87.4% and 38.7%, respectively, in comparison with that of monoculture faba bean (MF). Wheat and faba bean intercropping changed the types of OA exuded by roots. At tillering stage, lactic acid was identified in root exudates of intercropping wheat (IW), but not in that of MW. At jointing stage (98 d), citric acid was identified in root exudates of IW, but not in that of MW, and acetic acid was vice versa. At branching stage, acetic acid was identified in root exudates of intercropping faba bean (IF), but not in that of MF, and lactic acid was vice versa. At filling stage, lactic acid was identified in root exudates of IF, but not in that of MF. Wheat and faba bean intercropping increased the OA exudation rate of wheat. At booting stage, the exudation rates of citric and fumaric acid from IW were 179 and 184-times as that of from MW, respectively. At filling stage, the exudation rate of lactic acid from IW was 2.53-times as that from MW. In conclusion, wheat and faba bean intercropping increased the rate and total amount, and changed the types of OA exuded by roots.

  10. Comparing the performance of Miscanthus x giganteus and wheat straw biomass in sulfuric acid based pretreatment.

    PubMed

    Kärcher, M A; Iqbal, Y; Lewandowski, I; Senn, T

    2015-03-01

    The objective of this study was to assess and compare the suitability of Miscanthus x giganteus and wheat straw biomass in dilute acid catalyzed pretreatment. Miscanthus and wheat straw were treated in a dilute sulfuric acid/steam explosion pretreatment. As a result of combining dilute sulfuric acid- and steam explosion pretreatment the hemicellulose hydrolysis yields (96% in wheat straw and 90% in miscanthus) in both substrates were higher than reported in literature. The combined severity factor (=CSF) for optimal hemicellulose hydrolysis was 1.9 and 1.5 in for miscanthus and wheat straw respectively. Because of the higher CSF value more furfural, furfuryl alcohol, 5-hydroxymethylfurfural and acetic acid was formed in miscanthus than in wheat straw pretreatment.

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

    PubMed

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

    2014-10-01

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

  12. Biosynthesis of Essential Polyunsaturated Fatty Acids in Wheat Triggered by Expression of Artificial Gene.

    PubMed

    Mihálik, Daniel; Klčová, Lenka; Ondreičková, Katarína; Hudcovicová, Martina; Gubišová, Marcela; Klempová, Tatiana; Čertík, Milan; Pauk, János; Kraic, Ján

    2015-12-16

    The artificial gene D6D encoding the enzyme ∆⁶desaturase was designed and synthesized using the sequence of the same gene from the fungus Thamnidium elegans. The original start codon was replaced by the signal sequence derived from the wheat gene for high-molecular-weight glutenin subunit and the codon usage was completely changed for optimal expression in wheat. Synthesized artificial D6D gene was delivered into plants of the spring wheat line CY-45 and the gene itself, as well as transcribed D6D mRNA were confirmed in plants of T₀ and T₁ generations. The desired product of the wheat genetic modification by artificial D6D gene was the γ-linolenic acid. Its presence was confirmed in mature grains of transgenic wheat plants in the amount 0.04%-0.32% (v/v) of the total amount of fatty acids. Both newly synthesized γ-linolenic acid and stearidonic acid have been detected also in leaves, stems, roots, awns, paleas, rachillas, and immature grains of the T₁ generation as well as in immature and mature grains of the T₂ generation. Contents of γ-linolenic acid and stearidonic acid varied in range 0%-1.40% (v/v) and 0%-1.53% (v/v) from the total amount of fatty acids, respectively. This approach has opened the pathway of desaturation of fatty acids and production of essential polyunsaturated fatty acids in wheat.

  13. Biosynthesis of Essential Polyunsaturated Fatty Acids in Wheat Triggered by Expression of Artificial Gene

    PubMed Central

    Mihálik, Daniel; Klčová, Lenka; Ondreičková, Katarína; Hudcovicová, Martina; Gubišová, Marcela; Klempová, Tatiana; Čertík, Milan; Pauk, János; Kraic, Ján

    2015-01-01

    The artificial gene D6D encoding the enzyme ∆6desaturase was designed and synthesized using the sequence of the same gene from the fungus Thamnidium elegans. The original start codon was replaced by the signal sequence derived from the wheat gene for high-molecular-weight glutenin subunit and the codon usage was completely changed for optimal expression in wheat. Synthesized artificial D6D gene was delivered into plants of the spring wheat line CY-45 and the gene itself, as well as transcribed D6D mRNA were confirmed in plants of T0 and T1 generations. The desired product of the wheat genetic modification by artificial D6D gene was the γ-linolenic acid. Its presence was confirmed in mature grains of transgenic wheat plants in the amount 0.04%–0.32% (v/v) of the total amount of fatty acids. Both newly synthesized γ-linolenic acid and stearidonic acid have been detected also in leaves, stems, roots, awns, paleas, rachillas, and immature grains of the T1 generation as well as in immature and mature grains of the T2 generation. Contents of γ-linolenic acid and stearidonic acid varied in range 0%–1.40% (v/v) and 0%–1.53% (v/v) from the total amount of fatty acids, respectively. This approach has opened the pathway of desaturation of fatty acids and production of essential polyunsaturated fatty acids in wheat. PMID:26694368

  14. Does Wheat Genetically Modified for Disease Resistance Affect Root-Colonizing Pseudomonads and Arbuscular Mycorrhizal Fungi?

    PubMed Central

    Foetzki, Andrea; Luginbühl, Carolin; Winzeler, Michael; Kneubühler, Yvan; Matasci, Caterina; Mascher-Frutschi, Fabio; Kalinina, Olena; Boller, Thomas; Keel, Christoph; Maurhofer, Monika

    2013-01-01

    This study aimed to evaluate the impact of genetically modified (GM) wheat with introduced pm3b mildew resistance transgene, on two types of root-colonizing microorganisms, namely pseudomonads and arbuscular mycorrhizal fungi (AMF). Our investigations were carried out in field trials over three field seasons and at two locations. Serial dilution in selective King's B medium and microscopy were used to assess the abundance of cultivable pseudomonads and AMF, respectively. We developed a denaturing gradient gel electrophoresis (DGGE) method to characterize the diversity of the pqqC gene, which is involved in Pseudomonas phosphate solubilization. A major result was that in the first field season Pseudomonas abundances and diversity on roots of GM pm3b lines, but also on non-GM sister lines were different from those of the parental lines and conventional wheat cultivars. This indicates a strong effect of the procedures by which these plants were created, as GM and sister lines were generated via tissue cultures and propagated in the greenhouse. Moreover, Pseudomonas population sizes and DGGE profiles varied considerably between individual GM lines with different genomic locations of the pm3b transgene. At individual time points, differences in Pseudomonas and AMF accumulation between GM and control lines were detected, but they were not consistent and much less pronounced than differences detected between young and old plants, different conventional wheat cultivars or at different locations and field seasons. Thus, we conclude that impacts of GM wheat on plant-beneficial root-colonizing microorganisms are minor and not of ecological importance. The cultivation-independent pqqC-DGGE approach proved to be a useful tool for monitoring the dynamics of Pseudomonas populations in a wheat field and even sensitive enough for detecting population responses to altered plant physiology. PMID:23372672

  15. Beneficial effects of humic acid on micronutrient availability to wheat

    NASA Technical Reports Server (NTRS)

    Mackowiak, C. L.; Grossl, P. R.; Bugbee, B. G.

    2001-01-01

    Humic acid (HA) is a relatively stable product of organic matter decomposition and thus accumulates in environmental systems. Humic acid might benefit plant growth by chelating unavailable nutrients and buffering pH. We examined the effect of HA on growth and micronutrient uptake in wheat (Triticum aestivum L.) grown hydroponically. Four root-zone treatments were compared: (i) 25 micromoles synthetic chelate N-(4-hydroxyethyl)ethylenediaminetriacetic acid (C10H18N2O7) (HEDTA at 0.25 mM C); (ii) 25 micromoles synthetic chelate with 4-morpholineethanesulfonic acid (C6H13N4S) (MES at 5 mM C) pH buffer; (iii) HA at 1 mM C without synthetic chelate or buffer; and (iv) no synthetic chelate or buffer. Ample inorganic Fe (35 micromoles Fe3+) was supplied in all treatments. There was no statistically significant difference in total biomass or seed yield among treatments, but HA was effective at ameliorating the leaf interveinal chlorosis that occurred during early growth of the nonchelated treatment. Leaf-tissue Cu and Zn concentrations were lower in the HEDTA treatment relative to no chelate (NC), indicating HEDTA strongly complexed these nutrients, thus reducing their free ion activities and hence, bioavailability. Humic acid did not complex Zn as strongly and chemical equilibrium modeling supported these results. Titration tests indicated that HA was not an effective pH buffer at 1 mM C, and higher levels resulted in HA-Ca and HA-Mg flocculation in the nutrient solution.

  16. Exogenous Abscisic Acid and Gibberellic Acid Elicit Opposing Effects on Fusarium graminearum Infection in Wheat.

    PubMed

    Buhrow, Leann M; Cram, Dustin; Tulpan, Dan; Foroud, Nora A; Loewen, Michele C

    2016-09-01

    Although the roles of salicylate (SA) and jasmonic acid (JA) have been well-characterized in Fusarium head blight (FHB)-infected cereals, the roles of other phytohormones remain more ambiguous. Here, the association between an array of phytohormones and FHB pathogenesis in wheat is investigated. Comprehensive profiling of endogenous hormones demonstrated altered cytokinin, gibberellic acid (GA), and JA metabolism in a FHB-resistant cultivar, whereas challenge by Fusarium graminearum increased abscisic acid (ABA), JA, and SA in both FHB-susceptible and -resistant cultivars. Subsequent investigation of ABA or GA coapplication with fungal challenge increased and decreased FHB spread, respectively. These phytohormones-induced effects may be attributed to alteration of the F. graminearum transcriptome because ABA promoted expression of early-infection genes, including hydrolases and cytoskeletal reorganization genes, while GA suppressed nitrogen metabolic gene expression. Neither ABA nor GA elicited significant effects on F. graminearum fungal growth or sporulation in axenic conditions, nor do these phytohormones affect trichothecene gene expression, deoxynivalenol mycotoxin accumulation, or SA/JA biosynthesis in F. graminearum-challenged wheat spikes. Finally, the combined application of GA and paclobutrazol, a Fusarium fungicide, provided additive effects on reducing FHB severity, highlighting the potential for combining fungicidal agents with select phytohormone-related treatments for management of FHB infection in wheat. PMID:27135677

  17. Fatty acid production in genetically modified cyanobacteria

    PubMed Central

    Liu, Xinyao; Sheng, Jie; Curtiss III, Roy

    2011-01-01

    To avoid costly biomass recovery in photosynthetic microbial biofuel production, we genetically modified cyanobacteria to produce and secrete fatty acids. Starting with introducing an acyl–acyl carrier protein thioesterase gene, we made six successive generations of genetic modifications of cyanobacterium Synechocystis sp. PCC6803 wild type (SD100). The fatty acid secretion yield was increased to 197 ± 14 mg/L of culture in one improved strain at a cell density of 1.0 × 109 cells/mL by adding codon-optimized thioesterase genes and weakening polar cell wall layers. Although these strains exhibited damaged cell membranes at low cell densities, they grew more rapidly at high cell densities in late exponential and stationary phase and exhibited less cell damage than cells in wild-type cultures. Our results suggest that fatty acid secreting cyanobacteria are a promising technology for renewable biofuel production. PMID:21482809

  18. Effects of acetic acid and lactic acid on physicochemical characteristics of native and cross-linked wheat starches.

    PubMed

    Majzoobi, Mahsa; Beparva, Paniz

    2014-03-15

    The effects of two common organic acids; lactic and acetic acids (150 mg/kg) on physicochemical properties of native and cross-linked wheat starches were investigated prior and after gelatinization. These acids caused formation of some cracks and spots on the granules. The intrinsic viscosity of both starches decreased in the presence of the acids particularly after gelatinization. Water solubility increased while water absorption reduced after addition of the acids. The acids caused reduction in gelatinization temperature and enthalpy of gelatinization of both starches. The starch gels became softer, less cohesive, elastic and gummy when acids were added. These changes may indicate the degradation of the starch molecules by the acids. Cross-linked wheat starch was more resistant to the acids. However, both starches became more susceptible to the acids after gelatinization. The effect of lactic acid on physicochemical properties of both starches before and after gelatinization was greater than acetic acid.

  19. A simplified and accurate detection of the genetically modified wheat MON71800 with one calibrator plasmid.

    PubMed

    Kim, Jae-Hwan; Park, Saet-Byul; Roh, Hyo-Jeong; Park, Sunghoon; Shin, Min-Ki; Moon, Gui Im; Hong, Jin-Hwan; Kim, Hae-Yeong

    2015-06-01

    With the increasing number of genetically modified (GM) events, unauthorized GMO releases into the food market have increased dramatically, and many countries have developed detection tools for them. This study described the qualitative and quantitative detection methods of unauthorized the GM wheat MON71800 with a reference plasmid (pGEM-M71800). The wheat acetyl-CoA carboxylase (acc) gene was used as the endogenous gene. The plasmid pGEM-M71800, which contains both the acc gene and the event-specific target MON71800, was constructed as a positive control for the qualitative and quantitative analyses. The limit of detection in the qualitative PCR assay was approximately 10 copies. In the quantitative PCR assay, the standard deviation and relative standard deviation repeatability values ranged from 0.06 to 0.25 and from 0.23% to 1.12%, respectively. This study supplies a powerful and very simple but accurate detection strategy for unauthorized GM wheat MON71800 that utilizes a single calibrator plasmid.

  20. 40 CFR 721.3710 - Polyether modified fatty acids (generic).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Polyether modified fatty acids... Specific Chemical Substances § 721.3710 Polyether modified fatty acids (generic). (a) Chemical substance... Polyether modified fatty acids (PMN P-99-0435) is subject to reporting under this section for...

  1. 40 CFR 721.3710 - Polyether modified fatty acids (generic).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Polyether modified fatty acids... Specific Chemical Substances § 721.3710 Polyether modified fatty acids (generic). (a) Chemical substance... Polyether modified fatty acids (PMN P-99-0435) is subject to reporting under this section for...

  2. 40 CFR 721.3710 - Polyether modified fatty acids (generic).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Polyether modified fatty acids... Specific Chemical Substances § 721.3710 Polyether modified fatty acids (generic). (a) Chemical substance... Polyether modified fatty acids (PMN P-99-0435) is subject to reporting under this section for...

  3. 40 CFR 721.3710 - Polyether modified fatty acids (generic).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Polyether modified fatty acids... Specific Chemical Substances § 721.3710 Polyether modified fatty acids (generic). (a) Chemical substance... Polyether modified fatty acids (PMN P-99-0435) is subject to reporting under this section for...

  4. 40 CFR 721.3710 - Polyether modified fatty acids (generic).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Polyether modified fatty acids... Specific Chemical Substances § 721.3710 Polyether modified fatty acids (generic). (a) Chemical substance... Polyether modified fatty acids (PMN P-99-0435) is subject to reporting under this section for...

  5. Effect of citric acid deamidation on in vitro digestibility and antioxidant properties of wheat gluten.

    PubMed

    Qiu, Chaoying; Sun, Weizheng; Cui, Chun; Zhao, Mouming

    2013-12-01

    The effects of citric acid deamidation on the physiochemical properties of wheat gluten were investigated. In vitro digestion was carried out to determine changes of molecular weight distribution, amino acids composition and antioxidant efficacy of wheat gluten hydrolysates. Results indicated that citric acid deamidation significantly increased gluten solubility and surface hydrophobicity, at a neutral pH. Deamidation induced molecular weight distribution change of gluten with little proteolysis. Results from FTIR indicated that the α-helix and β-turn of deamidated gluten increased accompanied by a decrease of the β-sheet structure. After deamidation, in vitro pepsin digestibility of wheat gluten decreased, while in vitro pancreatin digestibility increased. The oxygen radical absorbance capacity (ORAC) activity of the in vitro digests decreased with increase of deamidation time. The high Lys and total essential AAs amounts in the final digests suggested that the nutritional values of wheat gluten after deamidation might be enhanced.

  6. Properties of wheat gluten/poly(lactic acid) laminates.

    PubMed

    Cho, Sung-Woo; Gällstedt, Mikael; Hedenqvist, Mikael S

    2010-06-23

    Laminates of compression-molded glycerol-plasticized wheat gluten (WG) films surrounded and supported by poly(lactic acid) (PLA) films have been produced and characterized. The objective was to obtain a fully renewable high gas barrier film with sufficient mechanical integrity to function in, for example, extrusion-coating paper/board applications. It was shown that the lamination made it possible to make films with a broad range of glycerol contents (0-30 wt %) with greater strength than single unsupported WG films. The low plasticizer contents yielded laminates with very good oxygen barrier properties. In addition, whereas the unsupported WG films had an immeasurably high water vapor transmission rate (WVTR), the laminate showed values that were finite and surprisingly, in several cases, also lower than that of PLA. Besides being a mechanical support (as evidenced by bending and tensile data) and a shield between the WG and surrounding moisture, the PLA layer also prevented the loss of the glycerol plasticizer from the WG layer. This was observed after the laminate had been aged on an "absorbing" blotting paper for up to 17 weeks. The interlayer adhesion (peel strength) decreased with decreasing glycerol content and increasing WG film molding temperature (130 degrees C instead of 110 degrees C). The latter effect was probably due to a higher protein aggregation, as revealed by infrared spectroscopy. The lamination temperature (110-140 degrees C) did not, however, have a major effect on the final peel strength. PMID:20504031

  7. Properties of wheat gluten/poly(lactic acid) laminates.

    PubMed

    Cho, Sung-Woo; Gällstedt, Mikael; Hedenqvist, Mikael S

    2010-06-23

    Laminates of compression-molded glycerol-plasticized wheat gluten (WG) films surrounded and supported by poly(lactic acid) (PLA) films have been produced and characterized. The objective was to obtain a fully renewable high gas barrier film with sufficient mechanical integrity to function in, for example, extrusion-coating paper/board applications. It was shown that the lamination made it possible to make films with a broad range of glycerol contents (0-30 wt %) with greater strength than single unsupported WG films. The low plasticizer contents yielded laminates with very good oxygen barrier properties. In addition, whereas the unsupported WG films had an immeasurably high water vapor transmission rate (WVTR), the laminate showed values that were finite and surprisingly, in several cases, also lower than that of PLA. Besides being a mechanical support (as evidenced by bending and tensile data) and a shield between the WG and surrounding moisture, the PLA layer also prevented the loss of the glycerol plasticizer from the WG layer. This was observed after the laminate had been aged on an "absorbing" blotting paper for up to 17 weeks. The interlayer adhesion (peel strength) decreased with decreasing glycerol content and increasing WG film molding temperature (130 degrees C instead of 110 degrees C). The latter effect was probably due to a higher protein aggregation, as revealed by infrared spectroscopy. The lamination temperature (110-140 degrees C) did not, however, have a major effect on the final peel strength.

  8. Pattern of aluminum-induced secretion of organic acids differs between rye and wheat.

    PubMed

    Li, X F; Ma, J F; Matsumoto, H

    2000-08-01

    Al-Induced secretion of organic acids from the roots has been considered as a mechanism of Al tolerance, but the processes leading to the secretion of organic acids are still unknown. In this study, the secretion pattern and alteration in the metabolism of organic acids under Al stress were examined in rye (Secale cereale L. cv King) and wheat (Triticum aestivum L. cv Atlas 66). Al induced rapid secretion of malate in the wheat, but a lag (6 and 10 h for malic and citric acids, respectively) between the exposure to Al and the secretion of organic acids was observed in the rye. The activities of isocitrate dehydrogenase, phosphoenolpyruvate carboxylase, and malate dehydrogenase were not affected by Al in either plant. The activity of citrate synthase was increased by the exposure to Al in the rye, but not in the wheat. The secretion of malate was not suppressed at low temperature in the wheat, but that of citrate was stopped in the rye. The Al-induced secretion of citrate from roots of the rye was inhibited by the inhibitors of a citrate carrier, which transports citrate from the mitochondria to the cytoplasm. All of these results suggest that alteration in the metabolism of organic acids is involved in the Al-induced secretion of organic acids in rye, but only activation of an anion channel seems to be responsible for the rapid secretion of malate in the wheat.

  9. Flanking sequence determination and event-specific detection of genetically modified wheat B73-6-1.

    PubMed

    Xu, Junyi; Cao, Jijuan; Cao, Dongmei; Zhao, Tongtong; Huang, Xin; Zhang, Piqiao; Luan, Fengxia

    2013-05-01

    In order to establish a specific identification method for genetically modified (GM) wheat, exogenous insert DNA and flanking sequence between exogenous fragment and recombinant chromosome of GM wheat B73-6-1 were successfully acquired by means of conventional polymerase chain reaction (PCR) and thermal asymmetric interlaced (TAIL)-PCR strategies. Newly acquired exogenous fragment covered the full-length sequence of transformed genes such as transformed plasmid and corresponding functional genes including marker uidA, herbicide-resistant bar, ubiquitin promoter, and high-molecular-weight gluten subunit. The flanking sequence between insert DNA revealed high similarity with Triticum turgidum A gene (GenBank: AY494981.1). A specific PCR detection method for GM wheat B73-6-1 was established on the basis of primers designed according to the flanking sequence. This specific PCR method was validated by GM wheat, GM corn, GM soybean, GM rice, and non-GM wheat. The specifically amplified target band was observed only in GM wheat B73-6-1. This method is of high specificity, high reproducibility, rapid identification, and excellent accuracy for the identification of GM wheat B73-6-1. PMID:23449073

  10. Biorefining of wheat straw using an acetic and formic acid based organosolv fractionation process.

    PubMed

    Snelders, Jeroen; Dornez, Emmie; Benjelloun-Mlayah, Bouchra; Huijgen, Wouter J J; de Wild, Paul J; Gosselink, Richard J A; Gerritsma, Jort; Courtin, Christophe M

    2014-03-01

    To assess the potential of acetic and formic acid organosolv fractionation of wheat straw as basis of an integral biorefinery concept, detailed knowledge on yield, composition and purity of the obtained streams is needed. Therefore, the process was performed, all fractions extensively characterized and the mass balance studied. Cellulose pulp yield was 48% of straw dry matter, while it was 21% and 27% for the lignin and hemicellulose-rich fractions. Composition analysis showed that 67% of wheat straw xylan and 96% of lignin were solubilized during the process, resulting in cellulose pulp of 63% purity, containing 93% of wheat straw cellulose. The isolated lignin fraction contained 84% of initial lignin and had a purity of 78%. A good part of wheat straw xylan (58%) ended up in the hemicellulose-rich fraction, half of it as monomeric xylose, together with proteins (44%), minerals (69%) and noticeable amounts of acids used during processing.

  11. Wheat germ agglutinin modified liposomes for the photodynamic inactivation of bacteria.

    PubMed

    Yang, Kewei; Gitter, Burkhard; Rüger, Ronny; Albrecht, Volker; Wieland, Gerhard D; Fahr, Alfred

    2012-01-01

    Photodynamic inactivation (PDI) of bacteria is a promising approach for combating the increasing emergence of antibiotic resistance in pathogenic bacteria. To further improve the PDI efficiency on bacteria, a bacteria-targeting liposomal formulation was investigated. A generation II photosensitizer (temoporfin) was incorporated into liposomes, followed by conjugation with a specific lectin (wheat germ agglutinin, WGA) on the liposomal surface. WGA was successfully coupled to temoporfin-loaded liposomes using an activated phospholipid containing N-hydroxylsuccinimide residue. Methicillin-resistant Staphylococcus aureus (MRSA) and Pseudomonas aeruginosa were selected to evaluate the WGA modified liposomes in terms of bacteria targeted delivery and in vitro PDI test. Fluorescence microscopy revealed that temoporfin was delivered to both kinds of bacteria, while flow cytometry demonstrated that WGA- modified liposomes delivered more temoporfin to bacteria compared to nonmodified liposomes. Consequently, the WGA- modified liposomes eradicated all MRSA and significantly enhanced the PDI of P. aeruginosa. In conclusion, the WGA- modified liposomes are a promising formulation for bacteria targeted delivery of temoporfin and for improving the PDI efficiency of temoporfin on both Gram-positive and Gram-negative bacterial cells.

  12. Wheat aleurone fractions and plasma n-3 fatty acids in rats.

    PubMed

    Ounnas, Fayçal; Salen, Patricia; Demeilliers, Christine; Calani, Luca; Scazzina, Francesca; Hazane-Puch, Florence; Laporte, Francois; Melegari, Camilla; Del Rio, Daniele; de Lorgeril, Michel

    2015-01-01

    The main aim of this study was to compare the effects of two wheat aleurone (WA) fractions on circulating n-3 fatty acids in rats. We demonstrated that only the fraction able to induce the highest urinary excretion of polyphenol metabolites (>1µmol) resulted in a significant increase in plasma level of Eicosapentanoic acid (+22%, p < 0.05). While other constituents of whole wheat can be involved in this response, our data suggest that cereals containing high levels of phenolic compounds can increase blood n-3 without affecting n-6 fatty acids. Further studies are required to confirm this hypothesis and explore the underlying biological mechanisms.

  13. Adsorption of phosphate from aqueous solutions onto modified wheat residue: characteristics, kinetic and column studies.

    PubMed

    Xu, Xing; Gao, Baoyu; Wang, Wenyi; Yue, Qinyan; Wang, Yu; Ni, Shouqing

    2009-04-01

    Kinetic and column adsorption of phosphate from aqueous solution using modified wheat residue (MWS) as an adsorbent were studied in a batch reactor. The respective characteristic rate constants and activation energy were presented after linear and non-linear fitting. In addition, the effects of influent concentration of phosphate and flow rates on the column adsorption were also investigated. The results showed that the adsorption process could reach equilibrium in 10-15 min, and the pseudo-second-order equation generated the best agreement with experimental data for adsorption systems. The activation energy was 3.39 kJ mol(-1) indicating that the synthesis process was a physical adsorption. In the column tests, the increase of influent concentration and flow rate both decreased the breakthrough time, and the MWS-packed column exhibited excellent phosphate removal from aqueous solution. These results provide strong evidence of the potential of MWS for the technological applications of phosphate removal from aqueous solutions.

  14. Toughness of natural rubber composites reinforced with hydrolyzed and modified wheat gluten aggregates

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The toughness of natural rubber can be improved by using fillers for various rubber applications. Dry wheat gluten is a protein from wheat flour and is sufficiently rigid for rubber reinforcement. The wheat gluten was hydrolyzed to reduce its particle size and microfluidized to reduce and homogenize...

  15. Selective hydrolysis of hemicellulose from wheat straw by a nanoscale solid acid catalyst.

    PubMed

    Zhong, Chao; Wang, Chunming; Huang, Fan; Wang, Fengxue; Jia, Honghua; Zhou, Hua; Wei, Ping

    2015-10-20

    A nanoscale catalyst, solid acid SO4(2-)/Fe2O3 with both Lewis and Brønsted acidity was found to effectively hydrolyze hemicellulose while keeping cellulose and lignin inactive, and selective hydrolysis of hemicellulose from wheat straw by this catalyst was also confirmed. The factors that significantly affected hydrolysis process were investigated with response surface methodology, and the optimum conditions for time, temperature, and ratio of wheat straw to catalyst (w/w) were calculated to be 4.10h, 141.97°C, and 1.95:1, respectively. A maximum hemicellulose hydrolysis yield of 63.5% from wheat straw could be obtained under these conditions. In addition, the catalyst could be recycled six times with high activity remaining.

  16. Effect of Modified Wheat Gluten on Boiling Resistance Capacity of Pork Meatballs.

    PubMed

    Wang, Kai-Qiang; Luo, Shui-Zhong; Zhong, Xi-Yang; Cai, Ke-Zhou; Cai, Jing; Jiang, Shao-Tong; Zheng, Zhi

    2016-02-01

    The effect of the modified wheat gluten (MWG) extender, prepared by alcalase-based hydrolysis and transglutaminase cross-linking, on meatballs was analyzed in this study. Here, we studied the effect of MWG addition on the boiling resistance capacity of pork meatballs (MB-MWG) at high temperature (100 °C) and increasing cooking time; meatballs with added soy protein isolates (MB-SPI) and raw wheat gluten (MB-WG) were used as references. The cooking loss, water-holding capacity (WHC), and textural properties of meatballs were investigated. The results revealed that MB-MWG showed lower cooking loss, which decreased by 49.16% compared to meatballs without added extenders when treated for 30 min. The WHC of MB-MWG significantly increased from 80.68% to 95.42%. The hardness, springiness, and chewiness (textural properties) of MB-MWG were also significantly increased by 97.05%, 6.68%, and 121.96%, respectively. The addition of MWG increased the cross-linking in meatballs during the cooking process, as indicated by the higher G'. SDS-PAGE indicated an obvious decrease in myosin heavy chain in MB-MWG cooked for 30 min at 100 °C, which was attributed to the interaction of myofibrillar proteins in pork meat with MWG. The nuclear magnetic resonance T2 relaxation time patterns indicated that MWG addition caused an increase in the bound water content, and decrease in the free water content, of meatballs. An analysis of the microstructures revealed that the MB-MWG formed the most regular and compact network. Therefore, MWG could be used as an ingredient to facilitate the processing of meat products.

  17. [Effect of phosphorus deficiency on activity of acid phosphatase exuded by wheat roots].

    PubMed

    Sun, Haiguo; Zhang, Fusuo

    2002-03-01

    The activity of acid phosphatase exuded by roots, the tissue location of the enzyme, and the relationship between the enzyme activity and phosphorus efficiency of wheat were studied. The results showed that the activity of acid phosphatase exuded by wheat 81(85)5-3-3-3 and NC37 under P-sufficiency treat were lower than those under P-deficiency, and the enzyme activity of the former variety was significantly higher than that of the latter. There was a significant difference in the enzyme activity among 12 wheat genotypes grown under P-deficiency treat. Acid phosphatase was exuded by epidermis cell of root, especially by epidermal cell of root apex. Thus, there was a linear relationship between the enzyme activity and the surface area of root or the number of root apexes. It implied that the enzyme activity was markedly related to the size of root system. The linear relationship between relative grain yield and acid phosphatase activity was significant. It indicates that the enzyme activity could be used as an early indicator to select P-efficient wheat genotypes.

  18. Modification of vital wheat gluten with phosphoric acid to produce high free-solution capacity

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Wheat gluten reacts with phosphoric acid to produce natural superabsorbent gels. The gel properties are defined by Fourier Transform Infra-red (FTIR) spectroscopy, 2-dimensional gel electrophoresis (2DE), and uptake of water, salt solutions, and aqueous ethanol. Temperatures above 120'C and dry cond...

  19. Modification of vital wheat gluten with phosphoric acid to produce high free solution capacity

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Wheat gluten reacts with phosphoric acid in the presence of urea to produce natural superabsorbent gels. Fourier Transform Infra-red (FT-IR) spectroscopy and two-dimensional gel electrophoresis (2DE) reveal chemical changes from the reaction. Temperatures above 120°C and dry conditions create the op...

  20. Virulent Hessian fly larvae manipulate the free amino acid content of host wheat plants.

    PubMed

    Saltzmann, Kurt D; Giovanini, Marcelo P; Zheng, Cheng; Williams, Christie E

    2008-11-01

    Gall-forming insects induce host plants to form specialized structures (galls) that provide immature life stages of the insect access to host plant nutrients and protection from natural enemies. Feeding by larvae of the Hessian fly (Mayetiola destructor Say) causes susceptible host wheat plants to produce a gall-like nutritive tissue that supports larval growth and development. To determine if changes in host plant free amino acid levels are associated with virulent Biotype L Hessian fly larval feeding, we quantified free amino acid levels in crown tissues of susceptible Newton wheat plants 1, 4, and 7 days after Hessian fly egg hatch. Hessian fly-infested susceptible plants were more responsive than resistant plants or uninfested controls, showing higher concentrations of alanine, glutamic acid, glycine, phenylalanine, proline, and serine 4 days after egg hatch. This 4-day post-hatch time point corresponds to the maturation of nutritive tissue cells in susceptible plants and the onset of rapid larval growth. By 7 days after egg hatch, when virulent second instars are actively feeding on the contents of nutritive tissue cells, the aromatic amino acids phenylalanine and tyrosine were more abundant compared to uninfested controls, but the levels of other free amino acids were no longer elevated. Changes in free amino acid abundance described in this report were associated with increased levels of mRNA encoded by wheat genes involved in amino acid synthesis and transport.

  1. Development of marker genes for jasmonic acid signaling in shoots and roots of wheat.

    PubMed

    Liu, Hongwei; Carvalhais, Lilia Costa; Kazan, Kemal; Schenk, Peer M

    2016-05-01

    The jasmonic acid (JA) signaling pathway plays key roles in a diverse array of plant development, reproduction, and responses to biotic and abiotic stresses. Most of our understanding of the JA signaling pathway derives from the dicot model plant Arabidopsis thaliana, while corresponding knowledge in wheat is somewhat limited. In this study, the expression of 41 genes implicated in the JA signaling pathway has been assessed on 10 day-old bread wheat seedlings, 24 h, 48 h, and 72 h after methyl-jasmonate (MeJA) treatment using quantitative real-time PCR. The examined genes have been previously reported to be involved in JA biosynthesis and catabolism, JA perception and signaling, and pathogen defense in wheat shoots and roots. This study provides evidence to suggest that the effect of MeJA treatment is more prominent in shoots than roots of wheat seedlings, and substantial regulation of the JA pathway-dependent defense genes occurs at 72 h after MeJA treatment. Results show that the expression of 22 genes was significantly affected by MeJA treatment in wheat shoots. However, only PR1.1 and PR3 were significantly differentially expressed in wheat roots, both at 24 h post-MeJA treatment, with other genes showing large variation in their gene expression in roots. While providing marker genes on JA signaling in wheat, future work may focus on elucidating the regulatory function of JA-modulated transcription factors, some of which have well-studied potential orthologs in Arabidopsis. PMID:27115051

  2. Production of hydrophobic amino acids from biobased resources: wheat gluten and rubber seed proteins.

    PubMed

    Widyarani; Sari, Yessie W; Ratnaningsih, Enny; Sanders, Johan P M; Bruins, Marieke E

    2016-09-01

    Protein hydrolysis enables production of peptides and free amino acids that are suitable for usage in food and feed or can be used as precursors for bulk chemicals. Several essential amino acids for food and feed have hydrophobic side chains; this property may also be exploited for subsequent separation. Here, we present methods for selective production of hydrophobic amino acids from proteins. Selectivity can be achieved by selection of starting material, selection of hydrolysis conditions, and separation of achieved hydrolysate. Several protease combinations were applied for hydrolysis of rubber seed protein concentrate, wheat gluten, and bovine serum albumin (BSA). High degree of hydrolysis (>50 %) could be achieved. Hydrophobic selectivity was influenced by the combination of proteases and by the extent of hydrolysis. Combination of Pronase and Peptidase R showed the highest selectivity towards hydrophobic amino acids, roughly doubling the content of hydrophobic amino acids in the products compared to the original substrates. Hydrophobic selectivity of 0.6 mol-hydrophobic/mol-total free amino acids was observed after 6 h hydrolysis of wheat gluten and 24 h hydrolysis of rubber seed proteins and BSA. The results of experiments with rubber seed proteins and wheat gluten suggest that this process can be applied to agro-industrial residues.

  3. Pressurized liquid extraction and HPLC quantification of folic acid in fortified wheat flours.

    PubMed

    Araújo, Michel Mozeika; Marchioni, Eric; Villavicencio, Anna Lucia Casañas Haasis; Zhao, Minjie; Zimmermann, Pierre; El-Khoury, Etienne; Bergaentzle, Martine

    2012-08-01

    A pressurized liquid extraction (PLE) method using phosphate buffer as solvent was applied for folic acid (FA) extraction from fortified wheat flours and was compared to a standard solid-liquid extraction (SLE) method. Extracted FA was quantified by reverse phase high-performance liquid chromatography (RP-HPLC) hyphenated with a phenyl column and an absorption photometric detector (λ = 280 nm). Detection and quantification limits were 0.12 and 0.4 ng, respectively, corresponding to 0.06 and 0.2 μg g(-1) of analyzed wheat flour. Equivalent FA contents were found by both extraction methods, but a single PLE allowed a total recovery of FA content, whereas at least three successive SLEs were needed to achieve a total recovery of FA. The obtained results indicated that PLE is a rapid and efficient technique for FA extraction from fortified wheat flour.

  4. Utilization of barley or wheat bran to bioconvert glutamate to γ-aminobutyric acid (GABA).

    PubMed

    Jin, Wen-Jie; Kim, Min-Ju; Kim, Keun-Sung

    2013-09-01

    This study deals with the utilization of agro-industrial wastes created by barley and wheat bran in the production of a value-added product, γ-aminobutyric acid (GABA). The simple and eco-friendly reaction requires no pretreatment or microbial fermentation steps but uses barley or wheat bran as an enzyme source, glutamate as a substrate, and pyridoxal 5'-phosphate (PLP) as a cofactor. The optimal reaction conditions were determined on the basis of the temperatures and times used for the decarboxylation reactions and the initial concentrations of barley or wheat bran, glutamate, and PLP. The optimal reactions produced 9.2 mM of GABA from 10 mM glutamate, yielding a 92% GABA conversion rate, when barley bran was used and 6.0 mM of GABA from 10 mM glutamate, yielding a 60% GABA conversion rate, when wheat bran was used. The results imply that barley bran is more efficient than wheat bran in the production of GABA.

  5. Acidic pretreatment of wheat straw in decanol for the production of surfactant, lignin and glucose.

    PubMed

    Marinkovic, Sinisa; Le Bras, Jean; Nardello-Rataj, Véronique; Agach, Mickaël; Estrine, Boris

    2012-01-01

    Wheat straw is an abundant residue of agriculture which is increasingly being considered as feedstock for the production of fuels, energy and chemicals. The acidic decanol-based pre-treatment of wheat straw has been investigated in this work. Wheat straw hemicellulose has been efficiently converted during a single step operation into decyl pentoside surfactants and the remaining material has been preserved keeping all its promises as potential feedstock for fuels or value added platform chemicals such as hydroxymethylfurfural (HMF). The enzymatic digestibility of the cellulose contained in the straw residue has been evaluated and the lignin prepared from the material characterized. Wheat-based surfactants thus obtained have exhibited superior surface properties compared to fossil-based polyethoxylates decyl alcohol or alkyl oligoglucosides, some of which are largely used surfactants. In view of the growing importance of renewable resource-based molecules in the chemical industry, this approach may open a new avenue for the conversion of wheat straw into various chemicals. PMID:22312256

  6. Acidic Pretreatment of Wheat Straw in Decanol for the Production of Surfactant, Lignin and Glucose

    PubMed Central

    Marinkovic, Sinisa; Le Bras, Jean; Nardello-Rataj, Véronique; Agach, Mickaël; Estrine, Boris

    2012-01-01

    Wheat straw is an abundant residue of agriculture which is increasingly being considered as feedstock for the production of fuels, energy and chemicals. The acidic decanol-based pre-treatment of wheat straw has been investigated in this work. Wheat straw hemicellulose has been efficiently converted during a single step operation into decyl pentoside surfactants and the remaining material has been preserved keeping all its promises as potential feedstock for fuels or value added platform chemicals such as hydroxymethylfurfural (HMF). The enzymatic digestibility of the cellulose contained in the straw residue has been evaluated and the lignin prepared from the material characterized. Wheat-based surfactants thus obtained have exhibited superior surface properties compared to fossil-based polyethoxylates decyl alcohol or alkyl oligoglucosides, some of which are largely used surfactants. In view of the growing importance of renewable resource-based molecules in the chemical industry, this approach may open a new avenue for the conversion of wheat straw into various chemicals. PMID:22312256

  7. No Adverse Effect of Genetically Modified Antifungal Wheat on Decomposition Dynamics and the Soil Fauna Community – A Field Study

    PubMed Central

    Duc, Caroline; Nentwig, Wolfgang; Lindfeld, Andreas

    2011-01-01

    The cultivation of genetically modified (GM) plants has raised several environmental concerns. One of these concerns regards non-target soil fauna organisms, which play an important role in the decomposition of organic matter and hence are largely exposed to GM plant residues. Soil fauna may be directly affected by transgene products or indirectly by pleiotropic effects such as a modified plant metabolism. Thus, ecosystem services and functioning might be affected negatively. In a litterbag experiment in the field we analysed the decomposition process and the soil fauna community involved. Therefore, we used four experimental GM wheat varieties, two with a race-specific antifungal resistance against powdery mildew (Pm3b) and two with an unspecific antifungal resistance based on the expression of chitinase and glucanase. We compared them with two non-GM isolines and six conventional cereal varieties. To elucidate the mechanisms that cause differences in plant decomposition, structural plant components (i.e. C∶N ratio, lignin, cellulose, hemicellulose) were examined and soil properties, temperature and precipitation were monitored. The most frequent taxa extracted from decaying plant material were mites (Cryptostigmata, Gamasina and Uropodina), springtails (Isotomidae), annelids (Enchytraeidae) and Diptera (Cecidomyiidae larvae). Despite a single significant transgenic/month interaction for Cecidomyiidae larvae, which is probably random, we detected no impact of the GM wheat on the soil fauna community. However, soil fauna differences among conventional cereal varieties were more pronounced than between GM and non-GM wheat. While leaf residue decomposition in GM and non-GM wheat was similar, differences among conventional cereals were evident. Furthermore, sampling date and location were found to greatly influence soil fauna community and decomposition processes. The results give no indication of ecologically relevant adverse effects of antifungal GM wheat on the

  8. No adverse effect of genetically modified antifungal wheat on decomposition dynamics and the soil fauna community--a field study.

    PubMed

    Duc, Caroline; Nentwig, Wolfgang; Lindfeld, Andreas

    2011-01-01

    The cultivation of genetically modified (GM) plants has raised several environmental concerns. One of these concerns regards non-target soil fauna organisms, which play an important role in the decomposition of organic matter and hence are largely exposed to GM plant residues. Soil fauna may be directly affected by transgene products or indirectly by pleiotropic effects such as a modified plant metabolism. Thus, ecosystem services and functioning might be affected negatively. In a litterbag experiment in the field we analysed the decomposition process and the soil fauna community involved. Therefore, we used four experimental GM wheat varieties, two with a race-specific antifungal resistance against powdery mildew (Pm3b) and two with an unspecific antifungal resistance based on the expression of chitinase and glucanase. We compared them with two non-GM isolines and six conventional cereal varieties. To elucidate the mechanisms that cause differences in plant decomposition, structural plant components (i.e. C∶N ratio, lignin, cellulose, hemicellulose) were examined and soil properties, temperature and precipitation were monitored. The most frequent taxa extracted from decaying plant material were mites (Cryptostigmata, Gamasina and Uropodina), springtails (Isotomidae), annelids (Enchytraeidae) and Diptera (Cecidomyiidae larvae). Despite a single significant transgenic/month interaction for Cecidomyiidae larvae, which is probably random, we detected no impact of the GM wheat on the soil fauna community. However, soil fauna differences among conventional cereal varieties were more pronounced than between GM and non-GM wheat. While leaf residue decomposition in GM and non-GM wheat was similar, differences among conventional cereals were evident. Furthermore, sampling date and location were found to greatly influence soil fauna community and decomposition processes. The results give no indication of ecologically relevant adverse effects of antifungal GM wheat on the

  9. Peroxidation radical formation and regiospecificity of recombinated Anabaena sp. lipoxygenase and its effect on modifying wheat proteins.

    PubMed

    Wang, Xiaoming; Lu, Fengxia; Zhang, Chong; Lu, Yingjian; Bie, Xiaomei; Ren, Di; Lu, Zhaoxin

    2014-02-19

    Peroxidation radical formation and the regiospecificity of recombinated lipoxygenase from Anabaena sp. PCC7120 (ana-rLOX) were characterized by using ESR and HPLC-MS. It was found that ana-rLOX oxygenated at the C-13 position of the substrate linoleic acid (LA); at C-13 and C-16 of α-linolenic acid (ALA); at C-9, C-12, and C-15 of arachidonic acid (AA); at C-12, C-15, and C-18 of eicosapentaenoic acid (EPA); and at C-14 and C-16 of docosahexaenoic acid (DHA), respectively. A total of 7, 14, 30, 28, and 18 radical adducts for LA, ALA, AA, EPA, and DHA were respectively identified by HPLC-MS. The functional characteristics of wheat protein, such as foaming capacity (FC), foam stability (FS), emulsifying activity index (EAI), emulsifying stability index (ESI), increased with enzymatic reactions. However, the average particle size of wheat proteins decreased with addition of ana-rLOX/LA. The ana-rLOX was also positivele effective in improving dough properties. These results provided clear evidence that ana-rLOX from Anabaena sp. could effectively improve the quality of wheat flour, which suggested that the enzyme could be applied as flour improver.

  10. Effect of wheat dried distillers grains and enzyme supplementation on growth rates, feed conversion ratio and beef fatty acid profile in feedlot steers.

    PubMed

    He, Z X; He, M L; Zhao, Y L; Xu, L; Walker, N D; Beauchemin, K A; McAllister, T A; Yang, W Z

    2015-10-01

    The objectives of this study were to determine: (1) the effect of wheat dried distillers grain with solubles (DDGS) inclusion, and (2) dietary feed enzyme (FE; Econase XT) supplementation in a finishing diet containing wheat DDGS on fatty acid profile of the pars costalis diaphragmatis muscle of beef cattle. A total of 160 crossbred yearling steers with initial BW of 495 ± 38 kg were blocked by BW and randomized into 16 pens (10 head/pen). The pens were randomly assigned to one of the four treatments: (1) control (CON; 10% barley silage and 90% barley grain-based concentrate, dry matter (DM) basis); (2) diet containing 30% wheat DDGS in place of barley grain without FE (WDG); (3) WDG diet supplemented with low FE (WDGL; 1 ml FE/kg DM); and (4) WDG diet supplemented with high FE (2 ml FE/kg DM). The pars costalis diaphragmatis muscle samples were collected from cattle at slaughter at the end of the finishing period (120 days) with a targeted live weight of 650 kg. No differences in organic matter intake, final BW and average daily gain were observed among treatments. However, steers fed WDG had greater (P<0.01) feed conversion ratio than those fed CON, and increasing FE application in wheat DDGS-based diets tended (P<0.10) to linearly decrease feed conversion ratio. In assessing the effects of including WDG diets without FE, concentration of total polyunsaturated fatty acids (PUFA) in muscle tended to be greater (P<0.10) for steers fed WDG than steers fed CON. In addition, inclusion of wheat DDGS into the diet increased (P<0.05) concentration of CLA and vaccenic acid (VA) in muscle and also resulted in a higher (P<0.05) ratio of n-6/n-3 PUFA compared with that from steers fed CON diet. Increasing FE application in wheat DDGS-based diets did not modify the concentrations of individual or total fatty acids. These results suggest that inclusion of wheat DDGS in finishing diets may improve fatty acid profile of beef muscle which could benefit human health.

  11. Surface acidity and degree of carburization of modified silver catalysts

    SciTech Connect

    Pestryakov, A.N.; Belousova, V.N.; Roznina, M.I.

    1993-11-10

    The effect has been studied of some compounds as modifying additives on the surface acidity, degree of carburization, aggregation and silver entrainement of silver-pumice catalysts for methanol oxidation. Catalyst samples have been tested in an industrial reactor. The probable mechanism of modifying action of the additives is discussed.

  12. Acidity characterization of a titanium and sulfate modified vermiculite

    SciTech Connect

    Hernandez, W.Y.; Centeno, M.A.; Odriozola, J.A.; Moreno, S.; Molina, R.

    2008-07-01

    A natural vermiculite has been modified with titanium and sulfated by the intercalation and impregnation method in order to optimize the acidity of the clay mineral, and characterization of samples were analyzed by X-ray fluorescence (XRF), X-ray diffraction (XRD), nitrogen adsorption isotherms, diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) and temperature programmed desorption with ammonia (TPD-NH{sub 3}). All the modified solids have a significantly higher number of acidic sites with respect to the parent material and in all of these, Broensted as well as Lewis acidity are identified. The presence of sulfate appears not to increase the number of acidic centers in the modified clay. For the materials sulfated with the intercalation method, it is observed that the strength of the acidic sites found in the material increases with the nominal sulfate/metal ratio. Nevertheless, when elevated quantities of sulfur are deposited, diffusion problems in the heptane reaction appear.

  13. Functionality of maize, wheat, teff and cassava starches with stearic acid and xanthan gum.

    PubMed

    Maphalla, Thabelang Gladys; Emmambux, Mohammad Naushad

    2016-01-20

    Consumer concerns to synthetic chemicals have led to strong preference for 'clean' label starches. Lipid and hydrocolloids are food friendly chemicals. This study determines the effects of stearic acid and xanthan gum alone and in combination on the functionality of maize, wheat, teff and cassava starches. An increase in viscosity was observed for all starches with stearic acid and xanthan gum compared to the controls with cassava having the least increase. A further increase in viscosity was observed for the cereal starches with combination of stearic acid and xanthan gum. Stearic acid reduced retrogradation, resulting in soft textured pastes. Combination of stearic acid and xanthan gum reduced the formation of type IIb amylose-lipid complexes, syneresis, and hysteresis in cereal starches compared to stearic acid alone. A combination of stearic acid and xanthan gum produce higher viscosity non-gelling starches and xanthan gum addition increases physical stability to freezing and better structural recovery after shear.

  14. Functionality of maize, wheat, teff and cassava starches with stearic acid and xanthan gum.

    PubMed

    Maphalla, Thabelang Gladys; Emmambux, Mohammad Naushad

    2016-01-20

    Consumer concerns to synthetic chemicals have led to strong preference for 'clean' label starches. Lipid and hydrocolloids are food friendly chemicals. This study determines the effects of stearic acid and xanthan gum alone and in combination on the functionality of maize, wheat, teff and cassava starches. An increase in viscosity was observed for all starches with stearic acid and xanthan gum compared to the controls with cassava having the least increase. A further increase in viscosity was observed for the cereal starches with combination of stearic acid and xanthan gum. Stearic acid reduced retrogradation, resulting in soft textured pastes. Combination of stearic acid and xanthan gum reduced the formation of type IIb amylose-lipid complexes, syneresis, and hysteresis in cereal starches compared to stearic acid alone. A combination of stearic acid and xanthan gum produce higher viscosity non-gelling starches and xanthan gum addition increases physical stability to freezing and better structural recovery after shear. PMID:26572436

  15. Dilute acid hydrolysis of wheat straw hemicellulose at moderate temperature: a simplified kinetic model

    SciTech Connect

    Gonzalez, G.; Lopez-Santin, J.; Caminal, G.; Sola, C.

    1986-02-01

    Wheat straw has been hydrolized with sulfuric acid at 34 and 90 degrees C. The treatment at 90 degrees C yields complete solubilization of hemicellulose to xylose and arabinose without significant amounts of furfural. The influence of acid concentration was studied and the kinetics of the acid-catalyzed hydrolysis has been modeled suggesting a two-consecutive reactions mechanism. This model is useful to explain the different behavior of the concentration of the two main sugars produced. The enhanced cellulose accessibility to enzymatic attack is also reported. 26 references.

  16. [Effects of simulated acid rain on leaf photosynthate, growth, and yield of wheat].

    PubMed

    Mai, Bo-Rui; Zheng, You-Fei; Liang, Jun; Liu, Xia; Li, Lu; Zhong, Yan-Chuan

    2008-10-01

    With winter wheat variety Yamgmai 12 as test object, a field experiment was conducted to study the stress of simulated acid rain on its growth and development. The results showed that simulated acid rain had considerable effect on wheat growth and yield. When the pH of acid rain was < or = 3.5, the growth of leaf area as well as the mass of fresh leaf per unit area declined greatly, and the yield was significantly lower than CK. When pH was < or = 2.5, the plant height was obviously lowered, and the visible injury on leaf surface was observed. Under acid rain stress, the contents of leaf chlorophyll a, chlorophyll b, and carotenoid, especially chlorophyll a, decreased obviously. Acid rain also suppressed the synthesis of soluble sugar and reduced sugar, and the suppression was stronger at pH < or = 3.5, and became much stronger with increasing acidity. The total free amino acid and soluble protein contents in leaves decreased with increasing acidity, and were significantly lower than CK when the pH was < or = 3.5 and < or = 4.5, respectively.

  17. Improved enzymatic hydrolysis of wheat straw by combined use of gamma ray and dilute acid for bioethanol production

    NASA Astrophysics Data System (ADS)

    Hyun Hong, Sung; Taek Lee, Jae; Lee, Sungbeom; Gon Wi, Seung; Ju Cho, Eun; Singh, Sudhir; Sik Lee, Seung; Yeoup Chung, Byung

    2014-01-01

    Pretreating wheat straw with a combination of dilute acid and gamma irradiation was performed in an attempt to enhance the enzymatic hydrolysis for bioethanol production. The glucose yield was significantly affected by combined pretreatment (3% sulfuric acid-gamma irradiation), compared with untreated wheat straw and individual pretreatment. The increasing enzymatic hydrolysis after combined pretreatment is resulting from decrease in crystallinity of cellulose, loss of hemicelluloses, and removal or modification of lignin. Therefore, combined pretreatment is one of the most effective methods for enhancing the enzymatic hydrolysis of wheat straw biomass.

  18. Identification of quantitative trait loci for abscisic acid responsiveness in the D-genome of hexaploid wheat.

    PubMed

    Iehisa, Julio C M; Matsuura, Takakazu; Mori, Izumi C; Yokota, Hirokazu; Kobayashi, Fuminori; Takumi, Shigeo

    2014-06-15

    In crop species such as wheat, abiotic stresses and preharvest sprouting reduce grain yield and quality. The plant hormone abscisic acid (ABA) plays important roles in abiotic stress tolerance and seed dormancy. In previous studies, we evaluated ABA responsiveness of 67 Aegilops tauschii accessions and their synthetic hexaploid wheat lines, finding wide variation that was due to the D-genome. In this study, quantitative trait locus (QTL) analysis was performed using an F2 population derived from crosses of highly ABA-responsive and less-responsive synthetic wheat lines. A significant QTL was detected on chromosome 6D, in a similar location to that reported for ABA responsiveness using recombinant inbred lines derived from common wheat cultivars Mironovskaya 808 and Chinese Spring. A comparative map and physiological and expression analyses of the 6D QTL suggested that this locus involved in line differences among wheat synthetics is different from that involved in cultivar differences in common wheat. The common wheat 6D QTL was found to affect seed dormancy and the regulation of cold-responsive/late embryogenesis abundant genes during dehydration. However, in synthetic wheat, we failed to detect any association of ABA responsiveness with abiotic stress tolerance or seed dormancy, at least under our experimental conditions. Development of near-isogenic lines will be important for functional analyses of the synthetic wheat 6D QTL. PMID:24877675

  19. Ferulic acid from aleurone determines the antioxidant potency of wheat grain (Triticum aestivum L.).

    PubMed

    Mateo Anson, Nuria; van den Berg, Robin; Havenaar, Rob; Bast, Aalt; Haenen, Guido R M M

    2008-07-23

    Grain is an important source of phytochemicals, which have potent antioxidant capacity. They have been implicated in the beneficial health effect of whole grains in reducing cardiovascular disease and type 2 diabetes. The aim of the present study was to identify the most important antioxidant fractions of wheat grain. It was found that the aleurone content of these fractions was highly correlated with the antioxidant capacity of the fractions (r = 0.96, p < 0.0001). Ferulic acid appeared to be the major contributor to the antioxidant capacity in fractions with higher antioxidant capacity. The contribution of protein was rather limited. It was concluded that the antioxidant potency of wheat grain fractions is predominantly determined by aleurone content, which can be attributed to the presence of relatively large amounts of phenolic compounds, primarily ferulic acid.

  20. Wheat germ oil and α-lipoic acid predominantly improve the lipid profile of broiler meat.

    PubMed

    Arshad, Muhammad Sajid; Anjum, Faqir Muhammad; Khan, Muhammad Issa; Shahid, Muhammad

    2013-11-20

    In response to recent assertions that synthetic antioxidants may have the potential to cause toxic effects and to consumers' increased attention to consuming natural products, the poultry industry has been seeking sources of natural antioxidants, alone or in combination with synthetic antioxidants that are currently being used by the industry. The present study was conducted to determine the effect of α-lipoic acid, α-tocopherol, and wheat germ oil on the status of antioxidant enzymes, fatty acid profile, and serum biochemical profile of broiler blood. One-day-old (180) broiler birds were fed six different feeds varying in their antioxidant content: no addition (T1), natural α-tocopherol (wheat germ oil, T2), synthetic α-tocopherol (T3), α-lipoic acid (T4), α-lipoic acid together with natural α-tocopherol (T5), and α-lipoic acid together with synthetic α-tocopherol (T6). The composition of saturated and unsaturated fatty acids in the breast and leg meat was positively influenced by the different dietary supplements. The content of fatty acid was significantly greater in broilers receiving T2 both in breast (23.92%) and in leg (25.82%) meat, whereas lower fatty acid levels was found in broilers receiving diets containing T6 in the breast (19.57%) and leg (21.30%) meat. Serum total cholesterol (113.42 mg/dL) and triglycerides (52.29 mg/dL) were lowest in the group given natural α-tocopherol and α-lipoic acid. Wheat germ oil containing natural α-tocopherol alone or with α-lipoic acid was more effective than synthetic α-tocopherol in raising levels of antioxidant enzymes superoxide dismutase, catalase, and glutathione reductase while lowering plasma total cholesterol, low-density lipoprotein, and triglycerides and raising high-density lipoprotein and plasma protein significantly. It was concluded that the combination of wheat germ oil and α-lipoic acid is helpful in improving the lipid profile of broilers. PMID:24191686

  1. Rhizosheaths on wheat grown in acid soils: phosphorus acquisition efficiency and genetic control

    PubMed Central

    James, Richard A.; Weligama, Chandrakumara; Verbyla, Klara; Ryan, Peter R.; Rebetzke, Gregory J.; Rattey, Allan; Richardson, Alan E.; Delhaize, Emmanuel

    2016-01-01

    Rhizosheaths comprise soil bound to roots, and in wheat (Triticum aestivum L.) rhizosheath size correlates with root hair length. The aims of this study were to determine the effect that a large rhizosheath has on the phosphorus (P) acquisition by wheat and to investigate the genetic control of rhizosheath size in wheat grown on acid soil. Near-isogenic wheat lines differing in rhizosheath size were evaluated on two acid soils. The soils were fertilized with mineral nutrients and included treatments with either low or high P. The same soils were treated with CaCO3 to raise the pH and detoxify Al3+. Genotypic differences in rhizosheath size were apparent only when soil pH was low and Al3+ was present. On acid soils, a large rhizosheath increased shoot biomass compared with a small rhizosheath regardless of P supply. At low P supply, increased shoot biomass could be attributed to a greater uptake of soil P, but at high P supply the increased biomass was due to some other factor. Generation means analysis indicated that rhizosheath size on acid soil was controlled by multiple, additive loci. Subsequently, a quantitative trait loci (QTL) analysis of an F6 population of recombinant inbred lines identified five major loci contributing to the phenotype together accounting for over 60% of the total genetic variance. One locus on chromosome 1D accounted for 34% of the genotypic variation. Genetic control of rhizosheath size appears to be relatively simple and markers based on the QTL provide valuable tools for marker assisted breeding. PMID:26873980

  2. Rhizosheaths on wheat grown in acid soils: phosphorus acquisition efficiency and genetic control.

    PubMed

    James, Richard A; Weligama, Chandrakumara; Verbyla, Klara; Ryan, Peter R; Rebetzke, Gregory J; Rattey, Allan; Richardson, Alan E; Delhaize, Emmanuel

    2016-06-01

    Rhizosheaths comprise soil bound to roots, and in wheat (Triticum aestivum L.) rhizosheath size correlates with root hair length. The aims of this study were to determine the effect that a large rhizosheath has on the phosphorus (P) acquisition by wheat and to investigate the genetic control of rhizosheath size in wheat grown on acid soil.Near-isogenic wheat lines differing in rhizosheath size were evaluated on two acid soils. The soils were fertilized with mineral nutrients and included treatments with either low or high P. The same soils were treated with CaCO3 to raise the pH and detoxify Al(3+) Genotypic differences in rhizosheath size were apparent only when soil pH was low and Al(3+) was present. On acid soils, a large rhizosheath increased shoot biomass compared with a small rhizosheath regardless of P supply. At low P supply, increased shoot biomass could be attributed to a greater uptake of soil P, but at high P supply the increased biomass was due to some other factor. Generation means analysis indicated that rhizosheath size on acid soil was controlled by multiple, additive loci. Subsequently, a quantitative trait loci (QTL) analysis of an F6 population of recombinant inbred lines identified five major loci contributing to the phenotype together accounting for over 60% of the total genetic variance. One locus on chromosome 1D accounted for 34% of the genotypic variation. Genetic control of rhizosheath size appears to be relatively simple and markers based on the QTL provide valuable tools for marker assisted breeding.

  3. Characterization of carbon black modified by maleic acid

    NASA Astrophysics Data System (ADS)

    Asokan, Vijayshankar; Kosinski, Pawel; Skodvin, Tore; Myrseth, Velaug

    2013-09-01

    We present here a method for modifying the surface of carbon black (CB) using a simple heat treatment in the presence of a carboxylic acid as well as water or ethylene glycol as a solvent. CB was mixed with maleic acid and either water or ethylene glycol, and heated at 250°C. Unlike the traditional surface modification processes which use heat treatment of carbon with mineral acids the present modification method using a carboxylic acid proved to be simple and time efficient. CB from two different vendors was used, and the modified samples were characterized by TGA, BET surface area measurement, XRD, particle size and zeta potential measurements, and FTIR. It was found that several material properties, including thermal stability and surface area, of the modified CB are significantly altered relative to the parental carbon samples. This method provides a rapid and simple route to tailor new materials with desired properties.

  4. Comparison of homo- and heterofermentative lactic acid bacteria for implementation of fermented wheat bran in bread.

    PubMed

    Prückler, Michael; Lorenz, Cindy; Endo, Akihito; Kraler, Manuel; Dürrschmid, Klaus; Hendriks, Karel; Soares da Silva, Francisco; Auterith, Eric; Kneifel, Wolfgang; Michlmayr, Herbert

    2015-08-01

    Despite its potential health benefits, the integration of wheat bran into the food sector is difficult due to several adverse technological and sensory properties such as bitterness and grittiness. Sourdough fermentation is a promising strategy to improve the sensory quality of bran without inducing severe changes to the bran matrix. Therefore, identification of species/strains with potential for industrial sourdough fermentations is important. We compared the effects of different representatives of species of lactic acid bacteria (LAB) on wheat bran. Lactobacillus plantarum, Lactobacillus pentosus, Lactobacillus brevis, Lactobacillus sanfranciscensis and Fructobacillus fructosus produced highly individual fermentation patterns as judged from carbohydrate consumption and organic acid production. Interestingly, fructose was released during all bran fermentations and possibly influenced the fermentation profiles of obligately heterofermentative species to varying degrees. Except for the reduction of ferulic acid by L. plantarum and L. pentosus, analyses of phenolic compounds and alkylresorcinols suggested that only minor changes thereof were induced by the LAB metabolism. Sensory analysis of breads baked with fermented bran did not reveal significant differences regarding perceived bitterness and aftertaste. We conclude that in addition to more traditionally used sourdough species such as L. sanfranciscensis and L. brevis, also facultatively heterofermentative species such as L. plantarum and L. pentosus possess potential for industrial wheat bran fermentations and should be considered in further investigations.

  5. Effects of exogenous salicylic acid on growth characteristics and biochemical content of wheat seeds under arsenic stress.

    PubMed

    Zengin, Fikriye

    2015-01-01

    The present study illustrates the phytotoxic effect of As on wheat seedlings and pre-application of salicylic acid in alleviating toxic effect of arsenic. Wheat seedlings treated with different concentrations (50-400 μM) of arsenic decreased the germination rate (34.7% and 86.9%), root and coleptile length, fresh and dry weight of roots and coleoptile, chlorophyll (67%) and protein content (27.1%), while increased proline and MDA content. However, pretreatment with 1mM saliycilic acid partially alleviated the toxic effect of arsenic on germination parameters and significantly reduced the proline (181.2%) and MDA (80%) content thereby increasing chlorophyll and protein content in As stressed wheat plants (p < 0.01 or p < 0.05). The data suggests that saliycilic acid reduced the damaging effects generated by As and enhanced the tolerance of wheat plants to arsenic toxicity.

  6. Effect of Wheat Dietary Fiber Particle Size during Digestion In Vitro on Bile Acid, Faecal Bacteria and Short-Chain Fatty Acid Content.

    PubMed

    Dziedzic, Krzysztof; Szwengiel, Artur; Górecka, Danuta; Gujska, Elżbieta; Kaczkowska, Joanna; Drożdżyńska, Agnieszka; Walkowiak, Jarosław

    2016-06-01

    The influence of bile acid concentration on the growth of Bifidobacterium spp. and Lactobacillus spp. bacteria was demonstrated. Exposing these bacteria to the environment containing bile acid salts, and very poor in nutrients, leads to the disappearance of these microorganisms due to the toxic effect of bile acids. A multidimensional analysis of data in the form of principal component analysis indicated that lactic acid bacteria bind bile acids and show antagonistic effect on E. coli spp. bacteria. The growth in E. coli spp. population was accompanied by a decline in the population of Bifidobacterium spp. and Lactobacillus spp. with a simultaneous reduction in the concentration of bile acids. This is direct proof of acid binding ability of the tested lactic acid bacteria with respect to cholic acid, lithocholic acid and deoxycholic acid. This research demonstrated that the degree of fineness of wheat dietary fibre does not affect the sorption of bile acids and growth of some bacteria species; however, it has an impact on the profile of synthesized short-chained fatty acids. During the digestion of a very fine wheat fibre fraction (WF 90), an increase in the concentration of propionic and butyric acids, as compared with the wheat fiber fraction of larger particles - WF 500, was observed. Our study suggested that wheat fibre did not affect faecal bacteria growth, however, we observed binding of bile acids by Bifidobacterium spp. and Lactobacillus spp.

  7. Effect of Wheat Dietary Fiber Particle Size during Digestion In Vitro on Bile Acid, Faecal Bacteria and Short-Chain Fatty Acid Content.

    PubMed

    Dziedzic, Krzysztof; Szwengiel, Artur; Górecka, Danuta; Gujska, Elżbieta; Kaczkowska, Joanna; Drożdżyńska, Agnieszka; Walkowiak, Jarosław

    2016-06-01

    The influence of bile acid concentration on the growth of Bifidobacterium spp. and Lactobacillus spp. bacteria was demonstrated. Exposing these bacteria to the environment containing bile acid salts, and very poor in nutrients, leads to the disappearance of these microorganisms due to the toxic effect of bile acids. A multidimensional analysis of data in the form of principal component analysis indicated that lactic acid bacteria bind bile acids and show antagonistic effect on E. coli spp. bacteria. The growth in E. coli spp. population was accompanied by a decline in the population of Bifidobacterium spp. and Lactobacillus spp. with a simultaneous reduction in the concentration of bile acids. This is direct proof of acid binding ability of the tested lactic acid bacteria with respect to cholic acid, lithocholic acid and deoxycholic acid. This research demonstrated that the degree of fineness of wheat dietary fibre does not affect the sorption of bile acids and growth of some bacteria species; however, it has an impact on the profile of synthesized short-chained fatty acids. During the digestion of a very fine wheat fibre fraction (WF 90), an increase in the concentration of propionic and butyric acids, as compared with the wheat fiber fraction of larger particles - WF 500, was observed. Our study suggested that wheat fibre did not affect faecal bacteria growth, however, we observed binding of bile acids by Bifidobacterium spp. and Lactobacillus spp. PMID:26924312

  8. Exogenous jasmonic acid can enhance tolerance of wheat seedlings to salt stress.

    PubMed

    Qiu, ZongBo; Guo, JunLi; Zhu, AiJing; Zhang, Liang; Zhang, ManMan

    2014-06-01

    Jasmonic acid (JA) is regarded as endogenous regulator that plays an important role in regulating stress responses, plant growth and development. To investigate the physiological mechanisms of salt stress mitigated by exogenous JA, foliar application of 2mM JA was done to wheat seedlings for 3days and then they were subjected to 150mM NaCl. Our results showed that 150mM NaCl treatment significantly decreased plant height, root length, shoot dry weight, root dry weight, the concentration of glutathione (GSH), chlorophyll b (Chl b) and carotenoid (Car), the activities of superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), ascorbate peroxidase (APX), enhanced the concentration of malondialdehyde (MDA), hydrogen peroxide (H2O2) and the rate of superoxide radical (O2•-) generation in the wheat seedlings when compared with the control. However, treatments with exogenous JA for 3 days significantly enhanced salt stress tolerance in wheat seedlings by decreasing the concentration of MDA and H2O2, the production rate of O2•- and increasing the transcript levels and activities of SOD, POD, CAT and APX and the contents of GSH, Chl b and Car, which, in turn, enhanced the growth of salt stressed seedlings. These results suggested that JA could effectively protect wheat seedlings from salt stress damage by enhancing activities of antioxidant enzymes and the concentration of antioxidative compounds to quench the excessive reactive oxygen species caused by salt stress and presented a practical implication for wheat cultivation in salt-affected soils.

  9. Stored wheat insect infestation related to uric acid as determined by liquid chromatography.

    PubMed

    Wehling, R L; Wetzel, D L; Pedersen, J R

    1984-01-01

    Liquid chromatography is used to measure the uric acid content of wheat internally infested by various growth stages of granary weevil (Sitophilus granarius), rice weevil (Sitophilus oryzae), and lesser grain borer (Ryzopertha dominica). Good correlation exists between numbers of insects and uric acid content of grain infested by a given stage of an internally infesting stored product insect, with correlation coefficients ranging from 0.970 to 0.998. Uric acid content of infested grain increases as the insect life cycle progresses, with granary weevil producing the greatest quantities of uric acid followed in order by rice weevil and lesser grain borer. A detection limit for the analytical procedure of less than 1.0 ppm uric acid allows detection of infestation levels as low as one kernel per 100 g grain for late instar granary weevil larvae. This limit is sufficiently sensitive to detect levels of infestation that may be commonly encountered in commerce.

  10. [Cellular delivery of modified peptide nucleic acids: a review].

    PubMed

    Liu, Chundong; Wang, Jianhua; Zeng, Fang

    2016-03-01

    Peptide nucleic acid (PNA) is a DNA surrogate in which the phosphate deoxyribose backbone of DNA is replaced by repeating N-(2-aminoethyl)glycine units. PNA can hybridize to the complementary DNA and RNA with higher affinity than their oligonucleotide counterparts. This character of PNA not only makes it a new tool for the studies of molecular biology but also the potential candidate for gene-targeting drugs. The non-ionic backbone of PNA leads to stable hybrids with the nucleic acids, but at the same time, the neutral backbone results in poor cellular uptake. To address this problem, studies on modified PNA progress rapidly in recent years. We reviewed literature reports combined with our study about the delivery methods, including backbone modified PNA and PNA-ligand conjugates, and the cellular uptake of modified PNA. In addition, we summarized the problems and future prospect of the cellular delivery of modified PNA.

  11. Low irradiances affect abscisic acid, indole-3-acidic acid, and cytokinin levels of wheat (Triticum aestivum L.) tissues

    NASA Technical Reports Server (NTRS)

    Nan, R.; Carman, J. G.; Salisbury, F. B.

    1999-01-01

    Wheat (Triticum aestivum L.) plants were grown under four irradiance levels: 1,400, 400, 200, and 100 micromol m-2 s-1. Leaves and roots were sampled before, during, and after the boot stage, and levels of abscisic acid (ABA), indole-3-acetic acid (IAA), zeatin, zeatin riboside, dihydrozeatin, dihydrozeatin riboside, isopentenyl adenine, and isopentenyl adenosine were quantified using noncompetitive indirect ELISA systems. Levels of IAA in leaves and roots of plants exposed to 100 micromol m-2 s-1 of irradiance were 0.7 and 2.9 micromol kg-1 dry mass (DM), respectively. These levels were 0.2 and 1.0 micromol kg-1 DM, respectively, when plants were exposed to 1,400 micromol m-2 s-1. Levels of ABA in leaves and roots of plants exposed to 100 micromol m-2 s-1 were 0.65 and 0.55 micromol kg-1 DM, respectively. They were 0.24 micromol kg-1 DM (both leaves and roots) when plants were exposed to 1,400 micromol m-2 s-1. Levels of isopentenyl adenosine in leaves (24.3 nmol kg-1 DM) and roots (29.9 nmol kg-1 DM) were not affected by differences in the irradiance regime. Similar values were obtained in a second experiment. Other cytokinins could not be detected (<10 nmol kg 1 DM) in either experiment with the sample sizes used (150-600 mg DM for roots and shoots, respectively).

  12. Acid Carboxypeptidases in Grains and Leaves of Wheat, Triticum aestivum L.

    PubMed

    Mikola, L

    1986-07-01

    Extracts of resting and germinating (3 days at 20 degrees C) wheat (Triticum aestivum L. cv Ruso) grains rapidly hydrolyzed various benzyloxycarbonyldipeptides (Z-dipeptides) at pH 4 to 6. Similar activities were present in extracts of mature flag leaves. Fractionation by chromatography on CM-cellulose and on Sephadex G-200 showed that the activities in germinating grains were due to five acid carboxypeptidases with different and complementary substrate specificities. The wheat enzymes appeared to correspond to the five acid carboxypeptidases present in germinating barley (L Mikola 1983 Biochim Biophys Acta 747: 241-252). The enzymes were designated wheat carboxypeptidases I to V and their best or most characteristic substrates and approximate molecular weights were: I, Z-Phe-Ala, 120,000; II, Z-Ala-Arg, 120,000; III, Z-Ala-Phe, 40,000; IV, Z-Pro-Ala, 165,000; and V, Z-Pro-Ala, 150,000. Resting grains contained carboxypeptidase II as a series of three isoenzymes and low activities of carboxypeptidases IV and V. During germination the activity of carboxypeptidase II decreased, those of carboxypeptidases IV and V increased, and high activities of carboxypeptidases I and III appeared. The flag leaves contained high activity of carboxypeptidase I and lower activities of carboxypeptidases II, IV, and V, whereas carboxypeptidase III was absent.

  13. Acid Carboxypeptidases in Grains and Leaves of Wheat, Triticum aestivum L

    PubMed Central

    Mikola, Leena

    1986-01-01

    Extracts of resting and germinating (3 days at 20°C) wheat (Triticum aestivum L. cv Ruso) grains rapidly hydrolyzed various benzyloxycarbonyldipeptides (Z-dipeptides) at pH 4 to 6. Similar activities were present in extracts of mature flag leaves. Fractionation by chromatography on CM-cellulose and on Sephadex G-200 showed that the activities in germinating grains were due to five acid carboxypeptidases with different and complementary substrate specificities. The wheat enzymes appeared to correspond to the five acid carboxypeptidases present in germinating barley (L Mikola 1983 Biochim Biophys Acta 747: 241-252). The enzymes were designated wheat carboxypeptidases I to V and their best or most characteristic substrates and approximate molecular weights were: I, Z-Phe-Ala, 120,000; II, Z-Ala-Arg, 120,000; III, Z-Ala-Phe, 40,000; IV, Z-Pro-Ala, 165,000; and V, Z-Pro-Ala, 150,000. Resting grains contained carboxypeptidase II as a series of three isoenzymes and low activities of carboxypeptidases IV and V. During germination the activity of carboxypeptidase II decreased, those of carboxypeptidases IV and V increased, and high activities of carboxypeptidases I and III appeared. The flag leaves contained high activity of carboxypeptidase I and lower activities of carboxypeptidases II, IV, and V, whereas carboxypeptidase III was absent. PMID:16664910

  14. The role of abscisic acid in the response of two different wheat varieties to water deficit.

    PubMed

    Mohamed, Hala Ezzat; Ismail, Ghada Saber M

    2009-01-01

    The changes in plant growth, transpiration rate, photosynthetic activity, plant pigments, electrolyte leakage, H2O2 content, lipid peroxidation, catalase activity and endogenous content of abscisic acid (ABA) were followed in the leaves of two wheat varieties (sakha 93 and 94) during drought stress and subsequent rehydration. Drought stress caused several inhibitory changes in the growth of both wheat varieties, particularly in sakha 94. Exogenous ABA treatment improved the growth of sakha 93 plants as indicated by a higher relative water content, transpiration rate and lower electrolyte leakage and also enhanced the growth during the recovery period. Such improvement may be the result of the induction of enzymatic (catalase) and non-enzymatic (carotenoid) systems. ABA treatment did not ameliorate the negative effect of drought on the growth of sakha 94.

  15. Flexible fibers wet-spun from formic acid modified chitosan.

    PubMed

    Li, Jinlei; Liu, Dagang; Hu, Chengming; Sun, Fengxiang; Gustave, Williamson; Tian, Huafeng; Yang, Shuguang

    2016-01-20

    The rigidity and low strain of chitosan fibers hindered their broader utility for biomedical applications. In present work, formic acid was employed as an efficient modifier for chitosan to prepare flexible fibers wet-spun from the formic acid modified chitosan solution. The formation of amide linkages between chitosan and formic acid was confirmed by FTIR, (13)C NMR, (1)H NMR and XRD measurements. The degree of formylation evaluated by (1)H NMR spectra was varied from 14.1% to 37.2% as a function of the reaction temperature. The results of the mechanical properties showed that the as-spun fibers exhibited an enhanced ductility with a maximum elongation at break of 21.7% compared with that spun from the chitosan dissolved in diluted acetic acid. The novel flexible chitosan fibers were anticipated to be used as comfortable wound dressing and bandages in biomedical fields.

  16. Polyglycolic acid microneedles modified with inkjet-deposited antifungal coatings.

    PubMed

    Boehm, Ryan D; Daniels, Justin; Stafslien, Shane; Nasir, Adnan; Lefebvre, Joe; Narayan, Roger J

    2015-01-01

    In this study, the authors examined use of piezoelectric inkjet printing to apply an antifungal agent, voriconazole, to the surfaces of biodegradable polyglycolic acid microneedles. Polyglycolic acid microneedles with sharp tips (average tip radius = 25 ± 3 μm) were prepared using a combination of injection molding and drawing lithography. The elastic modulus (9.9 ± 0.3 GPa) and hardness (588.2 ± 33.8 MPa) values of the polyglycolic acid material were determined using nanoindentation and were found to be suitable for use in transdermal drug delivery devices. Voriconazole was deposited onto the polyglycolic acid microneedles by means of piezoelectric inkjet printing. It should be noted that voriconazole has poor solubility in water; however, it is readily soluble in many organic solvents. Optical imaging, scanning electron microscopy, energy dispersive x-ray spectrometry, and Fourier transform infrared spectroscopy were utilized to examine the microneedle geometries and inkjet-deposited surface coatings. Furthermore, an in vitro agar plating study was performed on the unmodified, vehicle-modified, and voriconazole-modified microneedles. Unlike the unmodified and vehicle-modified microneedles, the voriconazole-modified microneedles showed antifungal activity against Candida albicans. The unmodified, vehicle-modified, and voriconazole-modified microneedles did not show activity against Escherichia coli, Pseudomonas aeruginosa, or Staphylococcus aureus. The results indicate that piezoelectric inkjet printing may be useful for loading transdermal drug delivery devices such as polyglycolic acid microneedles with antifungal pharmacologic agents and other pharmacologic agents with poor solubility in aqueous solutions.

  17. Polyglycolic acid microneedles modified with inkjet-deposited antifungal coatings.

    PubMed

    Boehm, Ryan D; Daniels, Justin; Stafslien, Shane; Nasir, Adnan; Lefebvre, Joe; Narayan, Roger J

    2015-01-01

    In this study, the authors examined use of piezoelectric inkjet printing to apply an antifungal agent, voriconazole, to the surfaces of biodegradable polyglycolic acid microneedles. Polyglycolic acid microneedles with sharp tips (average tip radius = 25 ± 3 μm) were prepared using a combination of injection molding and drawing lithography. The elastic modulus (9.9 ± 0.3 GPa) and hardness (588.2 ± 33.8 MPa) values of the polyglycolic acid material were determined using nanoindentation and were found to be suitable for use in transdermal drug delivery devices. Voriconazole was deposited onto the polyglycolic acid microneedles by means of piezoelectric inkjet printing. It should be noted that voriconazole has poor solubility in water; however, it is readily soluble in many organic solvents. Optical imaging, scanning electron microscopy, energy dispersive x-ray spectrometry, and Fourier transform infrared spectroscopy were utilized to examine the microneedle geometries and inkjet-deposited surface coatings. Furthermore, an in vitro agar plating study was performed on the unmodified, vehicle-modified, and voriconazole-modified microneedles. Unlike the unmodified and vehicle-modified microneedles, the voriconazole-modified microneedles showed antifungal activity against Candida albicans. The unmodified, vehicle-modified, and voriconazole-modified microneedles did not show activity against Escherichia coli, Pseudomonas aeruginosa, or Staphylococcus aureus. The results indicate that piezoelectric inkjet printing may be useful for loading transdermal drug delivery devices such as polyglycolic acid microneedles with antifungal pharmacologic agents and other pharmacologic agents with poor solubility in aqueous solutions. PMID:25732934

  18. [Influence of salicylic and succinic acids on formation of active oxygen forms in wheat coleoptiles].

    PubMed

    Kolupaiev, Iu Ie; Iastreb, T O; Shvidenko, M V; Karpets', Iu V

    2011-01-01

    The comparative study of influence of exogenous salicylic (SaA) and succinic (SuA) acids on the production of reactive oxygen species by isolated wheat coleoptiles has been provided. Under the action of both acids the increase of generation of superoxide anion-radical (O2(.-)) was observed. This increase was partially suppressed by treatment of coleoptiles with inhibitors of peroxidase (salicylhydroxamic acid) and NADP H-oxidase (imidazole and alpha-naphthol). The increase of hydrogen peroxide content, activity of peroxidase and superoxide dismutase (SOD) was registered under the influence of SaA and SuA; catalase activity did not change essentially. The treatment of coleoptiles with the indicated acids resulted in the increase of their resistance to abiotic stress (damaging heating, 43 +/- 0,1 degrees C, 10 min). The conclusion is made, that the increase of O2(.-) generation in wheat coleoptiles under the action of SaA and SuA is related, probably, to the increase of apoplast peroxidase and NADP.H-oxidase activity, and the rise of H2O2 content is related to the growth of SOD activity. These enzymatic systems are involved in the induction of plant cells protective reactions to the hyperthermia. PMID:22276431

  19. Phenylboronic-acid-modified nanoparticles: potential antiviral therapeutics.

    PubMed

    Khanal, Manakamana; Vausselin, Thibaut; Barras, Alexandre; Bande, Omprakash; Turcheniuk, Kostiantyn; Benazza, Mohammed; Zaitsev, Vladimir; Teodorescu, Cristian Mihail; Boukherroub, Rabah; Siriwardena, Aloysius; Dubuisson, Jean; Szunerits, Sabine

    2013-12-11

    Phenylboronic-acid-modified nanoparticles (NPs) are attracting considerable attention for biological and biomedical applications. We describe here a convenient and general protocol for attaching multiple copies of para-substituted phenylboronic acid moieties onto either iron-oxide-, silica- or diamond-derived NPs. The boronic acid functionalized NPs are all fabricated by first modifying the surface of each particle type with 4-azidobenzoic ester functions. These azide-terminated nanostructures were then reacted with 4-[1-oxo-4-pentyn-1-yl) amino]phenylboronic acid units via a Cu(I) catalyzed Huisgen cycloaddition to furnish, conveniently, the corresponding boronic-acid modified NPs (or "borono-lectins") targeted in this work. The potential of these novel "borono-lectins" as antiviral inhibitors was investigated against the Hepatitis C virus (HCV) exploiting a bioassay that measures the potential of drugs to interfere with the ability of cell-culture-derived JFH1 virus particles to infect healthy hepatocytes. As far as we are aware, this is the first report that describes NP-derived viral entry inhibitors and thus serves as a "proof-of-concept" study. The novel viral entry activity demonstrated, and the fact that the described boronic-acid-functionalized NPs all display much reduced cellular toxicities compared with alternate NPs, sets the stage for their further investigation. The data supports that NP-derived borono-lectins should be pursued as a potential therapeutic strategy for blocking viral entry of HCV.

  20. Impact of reagent infiltration time on reaction patterns and pasting properties of modified maize and wheat starches.

    PubMed

    Hong, Jung Sun; BeMiller, James N; Huber, Kerry C

    2016-10-20

    The impact of granular and molecular reaction patterns on modified starch properties was investigated as a function of the length of time allowed for reagent to infiltrate starch granules. A fluorescent reagent [5-(4,6-dichlorotriazinyl)aminofluorescein] was dispersed in aqueous normal maize or wheat starch slurries (35%, w/v) for 0, 5, 10, 30, or 60min, after which reaction was initiated by increasing the pH to 11.5 and allowing reaction to proceed for 3h. With increasing lengths of infiltration, the reaction became increasingly homogeneous within the granule interior (matrix) and the AM:AP reactivity ratio increased (wheat starch), as assessed by confocal laser scanning microscopy (CLSM) and size-exclusion chromatography (refractive index and fluorescence detection), respectively. A longer reagent infiltration time also led to a more inhibited (i.e., cross-linked) pasting viscosity, suggesting that both granular and/or molecular reaction patterns were altered by varied reagent infiltration times to ultimately impact modified starch properties.

  1. Accumulation of Phenolic Compounds and Expression Profiles of Phenolic Acid Biosynthesis-Related Genes in Developing Grains of White, Purple, and Red Wheat

    PubMed Central

    Ma, Dongyun; Li, Yaoguang; Zhang, Jian; Wang, Chenyang; Qin, Haixia; Ding, Huina; Xie, Yingxin; Guo, Tiancai

    2016-01-01

    Polyphenols in whole grain wheat have potential health benefits, but little is known about the expression patterns of phenolic acid biosynthesis genes and the accumulation of phenolic acid compounds in different-colored wheat grains. We found that purple wheat varieties had the highest total phenolic content (TPC) and antioxidant activity. Among phenolic acid compounds, bound ferulic acid, vanillic, and caffeic acid levels were significantly higher in purple wheat than in white and red wheat, while total soluble phenolic acid, soluble ferulic acid, and vanillic acid levels were significantly higher in purple and red wheat than in white wheat. Ferulic acid and syringic acid levels peaked at 14 days after anthesis (DAA), whereas p-coumaric acid and caffeic acid levels peaked at 7 DAA, and vanillic acid levels gradually increased during grain filling and peaked near ripeness (35 DAA). Nine phenolic acid biosynthesis pathway genes (TaPAL1, TaPAL2, TaC3H1, TaC3H2, TaC4H, Ta4CL1, Ta4CL2, TaCOMT1, and TaCOMT2) exhibited three distinct expression patterns during grain filling, which may be related to the different phenolic acids levels. White wheat had higher phenolic acid contents and relatively high gene expression at the early stage, while purple wheat had the highest phenolic acid contents and gene expression levels at later stages. These results suggest that the expression of phenolic acid biosynthesis genes may be closely related to phenolic acids accumulation. PMID:27148345

  2. [Effects of simulated acid rain and its acidified soil on soluble sugar and nitrogen contents of wheat seedlings].

    PubMed

    Tong, Guanhe; Liang, Huiling

    2005-08-01

    The study showed that the cation release of simulated rain caused soil acidification and base ions release. With the decrease of simulated acid rain pH from 5.6 to 2.5, the acid rain-leached soil pH decreased from 6.06 to 3.41, and its total amount of exchange base ions decreased from 56.5 to 41.1 mmol x kg(-1). Spraying simulated acid rain on the shoots of wheat seedlings planted on such acidified soils caused a rapid decrease in the soluble sugar and nitrogen contents of wheat seedlings, and reduced some of their physiological activities. The effect of spraying simulated acid rain on the soluble sugar, nitrogen, and chlorophyll contents and photosynthetic rate of wheat stems and leaves was larger than that of acidified soil, while the effect of the latter on the soluble sugar and nitrogen contents and the physiological activity of NR and GOGAT in root system of wheat seedlings was larger than that of the former. The intensive acid rain of pH < or = 3.0 and the corresponding acidified soil had an obvious harm to the growth and physiological activity of wheat seedlings.

  3. [Effects of simulated acid rain and its acidified soil on soluble sugar and nitrogen contents of wheat seedlings].

    PubMed

    Tong, Guanhe; Liang, Huiling

    2005-08-01

    The study showed that the cation release of simulated rain caused soil acidification and base ions release. With the decrease of simulated acid rain pH from 5.6 to 2.5, the acid rain-leached soil pH decreased from 6.06 to 3.41, and its total amount of exchange base ions decreased from 56.5 to 41.1 mmol x kg(-1). Spraying simulated acid rain on the shoots of wheat seedlings planted on such acidified soils caused a rapid decrease in the soluble sugar and nitrogen contents of wheat seedlings, and reduced some of their physiological activities. The effect of spraying simulated acid rain on the soluble sugar, nitrogen, and chlorophyll contents and photosynthetic rate of wheat stems and leaves was larger than that of acidified soil, while the effect of the latter on the soluble sugar and nitrogen contents and the physiological activity of NR and GOGAT in root system of wheat seedlings was larger than that of the former. The intensive acid rain of pH < or = 3.0 and the corresponding acidified soil had an obvious harm to the growth and physiological activity of wheat seedlings. PMID:16262064

  4. Structural and rheological characterisation of heteropolysaccharides produced by lactic acid bacteria in wheat and sorghum sourdough.

    PubMed

    Galle, Sandra; Schwab, Clarissa; Arendt, Elke K; Gänzle, Michael G

    2011-05-01

    Hydrocolloids improve the volume, texture, and shelf life of bread. Exopolysaccharides (EPS) produced by lactic acid bacteria (LAB) during sourdough fermentation can replace hydrocolloids. It was the aim of this study to determine whether heteropolysaccharides (HePS) synthesized intracellularly from sugar nucleotides by glycosyltransferases are produced in wheat and gluten-free sorghum sourdough at effective levels. The HePS-producing strains Lactobacillus casei FUA3185, L. casei FUA3186, and Lactobacillus buchneri FUA3154 were used; Weissella cibaria 10M producing no EPS in the absence of sucrose served as control strain. Cell suspensions of L. buchneri in MRS showed the highest viscosity at low shear rate. Glycosyltransferase genes responsible of HePS formation in LAB were expressed in sorghum and wheat sourdough. However, only HePS produced by L. buchneri influenced the rheological properties of sorghum sourdoughs but not of wheat sourdoughs. Sorghum sourdough fermented with L. buchneri exhibited a low |G*| compared to the control, indicating a decrease in resistance to deformation. An increase in tan δ indicated decreased elasticity. The use of LAB producing HePS expands the diversity of EPS and increases the variety of cultures for use in baking.

  5. Synthesis and role of salicylic acid in wheat varieties with different levels of cadmium tolerance.

    PubMed

    Kovács, Viktória; Gondor, Orsolya K; Szalai, Gabriella; Darkó, Eva; Majláth, Imre; Janda, Tibor; Pál, Magda

    2014-09-15

    Wheat genotypes with different endogenous SA contents were investigated, in order to reveal how cadmium influences salicylic acid (SA) synthesis, and to find possible relationships between SA and certain protective compounds (members of the antioxidants and the heavy metal detoxification system) and between the SA content and the level of cadmium tolerance. Cadmium exposure induced SA synthesis, especially in the leaves, and it is suggested that the phenyl-propanoid synthesis pathway is responsible for the accumulation of SA observed after cadmium stress. Cadmium influenced the synthesis and activation of protective compounds to varying extents in wheat genotypes with different levels of tolerance; the roots and leaves also responded differently to cadmium stress. Although a direct relationship was not found between the initial SA levels and the degree of cadmium tolerance, the results suggest that the increase in the root SA level during cadmium stress in the Mv varieties could be related with the enhancement of the internal glutathione cycle, thus inducing the antioxidant and metal detoxification systems, which promote Cd stress tolerance in wheat seedlings. The positive correlation between certain SA-related compounds and protective compounds suggests that SA-related signalling may also play a role in the acclimation to heavy metal stress. PMID:25113613

  6. Improvement of Functional Properties of Wheat Gluten Using Acid Protease from Aspergillus usamii.

    PubMed

    Deng, Lingli; Wang, Zhaoxia; Yang, Sheng; Song, Junmei; Que, Fei; Zhang, Hui; Feng, Fengqin

    2016-01-01

    Hydrolysis parameters (temperature, E/S ratio, pH, and time) for acid protease (from Aspergillus usamii) hydrolysis of wheat gluten were optimized by response surface methodology (RSM) using emulsifying activity index (EAI) as the response factor. A temperature of 48.9°C, E/S ratio of 1.60%, pH 3.0, hydrolysis time of 2.5 h was found to be the optimum condition to obtain wheat gluten hydrolysate with higher EAI. The solubility of wheat gluten was greatly improved by hydrolysis and became independent of pH over the studied range. Enzymatic hydrolysis resulted in dramatically increase in EAI, water and oil holding capacity. Molecular weight distribution results showed that most of the peptides above 10 kDa have been hydrolyzed into smaller peptides. The results of FTIR spectra and disulfide bond (SS) and sulfhydryl (SH) content suggested that a more extensional conformation was formed after hydrolysis, which could account for the improved functional properties. PMID:27467884

  7. Fusarium Head Blight Control and Prevention of Mycotoxin Contamination in Wheat with Botanicals and Tannic Acid

    PubMed Central

    Forrer, Hans-Rudolf; Musa, Tomke; Schwab, Fabienne; Jenny, Eveline; Bucheli, Thomas D.; Wettstein, Felix E.; Vogelgsang, Susanne

    2014-01-01

    Suspensions or solutions with 1% of Chinese galls (Galla chinensis, GC) or 1% of tannic acid (TA), inhibited germination of conidia or mycelium growth of Fusarium graminearum (FG) by 98%–100% or by 75%–80%, respectively, whereas dried bark from buckthorn (Frangula alnus, FA) showed no effect at this concentration. In climate chamber experiments where the wheat variety “Apogee” was artificially inoculated with FG and F. crookwellense (FCr) and treated with 5% suspensions of TA, GC and FA, the deoxynivalenol (DON) content in grains was reduced by 81%, 67% and 33%, respectively. In field experiments with two commercial wheat varieties and artificial or semi-natural inoculations, mean DON reductions of 66% (TA) and 58% (FA), respectively, were obtained. Antifungal toxicity can explain the high efficacies of TA and GC but not those of FA. The Fusarium head blight (FHB) and mycotoxin reducing effect of FA is probably due to elicitation of resistance in wheat plants. With semi-natural inoculation, a single FA application in the first half of the flowering period performed best. However, we assume that applications of FA at the end of ear emergence and a treatment, triggered by an infection period, with TA or GC during flowering, might perform better than synthetic fungicides. PMID:24577585

  8. Acceleration of the herbicide isoproturon degradation in wheat by glycosyltransferases and salicylic acid.

    PubMed

    Lu, Yi Chen; Zhang, Shuang; Yang, Hong

    2015-01-01

    Isoproturon (IPU) is a herbicide widely used to prevent weeds in cereal production. Due to its extensive use in agriculture, residues of IPU are often detected in soils and crops. Overload of IPU to crops is associated with human health risks. Hence, there is an urgent need to develop an approach to mitigate its accumulation in crops. In this study, the IPU residues and its degradation products in wheat were characterized using ultra performance liquid chromatography-time of fight tandem-mass spectrometer/mass spectrometer (UPLC-TOF-MS/MS). Most detected IPU-derivatives were sugar-conjugated. Degradation and glycosylation of IPU-derivatives could be enhanced by applying salicylic acid (SA). While more sugar-conjugated IPU-derivatives were identified in wheat with SA application, lower levels of IPU were detected, indicating that SA is able to accelerate intracellular IPU catabolism. All structures of IPU-derivatives and sugar-conjugated products were characterized. Comparative data were provided with specific activities and gene expression of certain glucosyltransferases. A pathway with IPU degradation and glucosylation was discussed. Our work indicates that SA-accelerated degradation is practically useful for wheat crops growing in IPU-contaminated soils because such crops with SA application can potentially lower or minimize IPU accumulation in levels below the threshold for adverse effects.

  9. Improvement of Functional Properties of Wheat Gluten Using Acid Protease from Aspergillus usamii

    PubMed Central

    Deng, Lingli; Wang, Zhaoxia; Yang, Sheng; Song, Junmei; Que, Fei; Zhang, Hui; Feng, Fengqin

    2016-01-01

    Hydrolysis parameters (temperature, E/S ratio, pH, and time) for acid protease (from Aspergillus usamii) hydrolysis of wheat gluten were optimized by response surface methodology (RSM) using emulsifying activity index (EAI) as the response factor. A temperature of 48.9°C, E/S ratio of 1.60%, pH 3.0, hydrolysis time of 2.5 h was found to be the optimum condition to obtain wheat gluten hydrolysate with higher EAI. The solubility of wheat gluten was greatly improved by hydrolysis and became independent of pH over the studied range. Enzymatic hydrolysis resulted in dramatically increase in EAI, water and oil holding capacity. Molecular weight distribution results showed that most of the peptides above 10 kDa have been hydrolyzed into smaller peptides. The results of FTIR spectra and disulfide bond (SS) and sulfhydryl (SH) content suggested that a more extensional conformation was formed after hydrolysis, which could account for the improved functional properties. PMID:27467884

  10. Synthesis and role of salicylic acid in wheat varieties with different levels of cadmium tolerance.

    PubMed

    Kovács, Viktória; Gondor, Orsolya K; Szalai, Gabriella; Darkó, Eva; Majláth, Imre; Janda, Tibor; Pál, Magda

    2014-09-15

    Wheat genotypes with different endogenous SA contents were investigated, in order to reveal how cadmium influences salicylic acid (SA) synthesis, and to find possible relationships between SA and certain protective compounds (members of the antioxidants and the heavy metal detoxification system) and between the SA content and the level of cadmium tolerance. Cadmium exposure induced SA synthesis, especially in the leaves, and it is suggested that the phenyl-propanoid synthesis pathway is responsible for the accumulation of SA observed after cadmium stress. Cadmium influenced the synthesis and activation of protective compounds to varying extents in wheat genotypes with different levels of tolerance; the roots and leaves also responded differently to cadmium stress. Although a direct relationship was not found between the initial SA levels and the degree of cadmium tolerance, the results suggest that the increase in the root SA level during cadmium stress in the Mv varieties could be related with the enhancement of the internal glutathione cycle, thus inducing the antioxidant and metal detoxification systems, which promote Cd stress tolerance in wheat seedlings. The positive correlation between certain SA-related compounds and protective compounds suggests that SA-related signalling may also play a role in the acclimation to heavy metal stress.

  11. Acid-catalyzed autohydrolysis of wheat straw to improve sugar recovery.

    PubMed

    Ertas, Murat; Han, Qiang; Jameel, Hasan

    2014-10-01

    A comparison study of autohydrolysis and acid-catalyzed autohydrolysis of wheat straw was performed to understand the impact of acid addition on overall sugar recovery. Autohydrolysis combined with refining is capable of achieving sugar recoveries in the mid 70s. If the addition of a small amount of acid is capable of increasing the sugar recovery even higher it may be economically attractive. Acetic, sulfuric, hydrochloric and sulfurous acids were selected for acid-catalyzed autohydrolysis pretreatments. Autohydrolysis with no acid at 190 °C showed the highest total sugar in the prehydrolyzate. Enzymatic hydrolysis was performed for all the post-treated solids with and without refining at enzyme loadings of 4 and 10 FPU/g for 96 h. Acid-catalyzed autohydrolysis at 190 °C with sulfurous acid showed the highest total sugar recovery of 81.2% at 4 FPU/g enzyme charge compared with 64.3% at 190 °C autohydrolysis without acid.

  12. Salicylic Acid Induction of Flavonoid Biosynthesis Pathways in Wheat Varies by Treatment

    PubMed Central

    Gondor, Orsolya K.; Janda, Tibor; Soós, Vilmos; Pál, Magda; Majláth, Imre; Adak, Malay K.; Balázs, Ervin; Szalai, Gabriella

    2016-01-01

    Salicylic acid is a promising compound for the reduction of stress sensitivity in plants. Although several biochemical and physiological changes have been described in plants treated with salicylic acid, the mode of action of the various treatments has not yet been clarified. The present work reports a detailed comparative study on the effects of different modes of salicylic acid application at the physiological, metabolomic, and transcriptomic levels. Seed soaking and hydroponic treatments were found to induce various changes in the protective mechanisms of wheat plants. The possible involvement of the flavonoid metabolism in salicylic acid-related stress signaling was also demonstrated. Different salicylic acid treatments were shown to induce different physiological and biochemical processes, with varying responses in the leaves and roots. Hydroponic treatment enhanced the level of oxidative stress, the expression of genes involved in the flavonoid metabolism and the amount of non-enzymatic antioxidant compounds, namely ortho-hydroxycinnamic acid and the flavonol quercetin in the leaves, while it decreased the ortho-hydroxycinnamic acid and flavonol contents and enhanced ascorbate peroxidase activity in the roots. In contrast, seed soaking only elevated the gene expression level of phenylalanine ammonia lyase in the roots and caused a slight increase in the amount of flavonols. These results draw attention to the fact that the effects of exogenous salicylic acid application cannot be generalized in different experimental systems and that the flavonoid metabolism may be an important part of the action mechanisms induced by salicylic acid. PMID:27733857

  13. Effect of thermal, acid, alkaline and alkaline-peroxide pretreatments on the biochemical methane potential and kinetics of the anaerobic digestion of wheat straw and sugarcane bagasse.

    PubMed

    Bolado-Rodríguez, Silvia; Toquero, Cristina; Martín-Juárez, Judit; Travaini, Rodolfo; García-Encina, Pedro Antonio

    2016-02-01

    The effect of thermal, acid, alkaline and alkaline-peroxide pretreatments on the methane produced by the anaerobic digestion of wheat straw (WS) and sugarcane bagasse (SCB) was studied, using whole slurry and solid fraction. All the pretreatments released formic and acetic acids and phenolic compounds, while 5-hydroxymetilfurfural (HMF) and furfural were generated only by acid pretreatment. A remarkable inhibition was found in most of the whole slurry experiments, except in thermal pretreatment which improved methane production compared to the raw materials (29% for WS and 11% for SCB). The alkaline pretreatment increased biodegradability (around 30%) and methane production rate of the solid fraction of both pretreated substrates. Methane production results were fitted using first order or modified Gompertz equations, or a novel model combining both equations. The model parameters provided information about substrate availability, controlling step and inhibitory effect of compounds generated by each pretreatment.

  14. Toxicity and subcellular distribution of cadmium in wheat as affected by dissolved organic acids.

    PubMed

    Li, Dandan; Zhou, Dongmei

    2012-01-01

    We aim to investigate the effects of humic acid (HA) and citric acid (CA) on the toxicity and subcellular distribution of Cd in wheat. Results show that the toxicity and uptake of Cd decreased with increasing HA. The EC50 values of Cd increased from 3.36 micromol/L to 4.96 and 7.33 micromol/L at 50 and 250 mg/L HA, respectively, but decreased to 1.39 micromol/L in the presence of CA based on free ion activity model (FIAM). HA decreased the relative subcellular distribution of Cd in the heat-denatured proteins (decreased from 54% to 33%) but increased Cd in the heat-stable proteins in root (from 25% to 50%) at 7.61 micromol/L {Cd2+} (free Cd activity), which resulted in decreasing Cd toxicity. However, CA increased Cd toxicity due to the increased internalization of Cd although the relative subcellular distributions of Cd exhibited a decrease in the heat-denatured proteins and increase in the granule fraction compared to the control at high-level Cd. The FIAM could not predict the toxicity of Cd in the presence of organic acids. Alternatively, the internal Cd accumulation and subcellular Cd concentration were better to describe the toxicity of Cd to wheat.

  15. Analysis of fatty acid steryl esters in tetraploid and hexaploid wheats: identification and comparison between chromatographic methods.

    PubMed

    Caboni, Maria Fiorenza; Iafelice, Giovanna; Pelillo, Marco; Marconi, Emanuele

    2005-09-21

    Fatty acid steryl esters (FASE) in whole meal of 14 genotypes of tetraploid wheats (Triticum dicocconand T. durum) and 17 genotypes of hexaploid wheats (T. spelta and T. aestivum) were analyzed using different chromatographic strategies. By both GC-FID and HPLC-ELSD, tetraploid wheats are lacking two major peaks. The amounts of FASE, calculated on the basis of the GC-FID analysis, were double in hexaploid species as compared to tetraploids (40 and 20 mg/100 g db, respectively). HPLC with ESI-MS detection enabled the identification of FASE by the characteristic fragmentations and ion-adducts of each molecule. The distribution of steryl residues was not different between the wheat species: the main class of steryl derivatives found was the beta-sitosteryl derivatives, followed by campesteryl derivatives with small amounts of stigmasteryl esters. The esterified fatty acids explain the difference between the hexaploid and tetraploid wheats. In particular, small amounts of campesteryl and beta-sitosteryl, while no trace of stigmasteryl palmitates, were found in T. durum or its hulled ancestor T. dicoccon. Steryl oleates were not detectable in T. aestivum or its hulled ancestor T. spelta, which is consistent with the filogenesis of tetraploid and hexaploid species. Both chromatographic techniques (GC and HPLC) showed that FASE are useful to discriminate between hexaploid and tetraploid wheats from both qualitative and quantitative points of view.

  16. One step conversion of wheat straw to sugars by simultaneous ball milling, mild acid, and fungus Penicillium simplicissimum treatment.

    PubMed

    Yuan, Li; Chen, Zhenhua; Zhu, Yonghua; Liu, Xuanming; Liao, Hongdong; Chen, Ding

    2012-05-01

    Wheat straw is one of the major lignocellulosic plant residues in many countries including China. An attractive alternative is the utilization of wheat straw for bioethanol production. This article mainly studies a simple one-step wet milling with Penicillium simplicissimum and weak acid to hydrolysis of wheat straw. The optimal condition for hydrolysis was ball milling 48 h in citrate solvent (pH = 4) with P. simplicissimum H5 at the speed of 500 rpm and the yield of sugar increased with increased milling time. Corresponding structure transformations before and after milling analyzed by X-ray diffraction, transmission Fourier transform infrared spectroscopy, and environmental scanning electron microscopy clearly indicated that this combined treatment could be attributed to the crystalline and chemical structure changes of cellulose in wheat straw during ball milling. This combined treatment of ball milling, mild acid, and fungus hydrolysis enabled the conversion of the wheat straw. Compared with traditional method of ball milling, this work showed a more simple, novel, and environmentally friendly way in mechanochemical treatment of wheat straw.

  17. Natural Lactic Acid Bacteria Population and Silage Fermentation of Whole-crop Wheat

    PubMed Central

    Ni, Kuikui; Wang, Yanping; Cai, Yimin; Pang, Huili

    2015-01-01

    Winter wheat is a suitable crop to be ensiled for animal feed and China has the largest planting area of this crop in the world. During the ensiling process, lactic acid bacteria (LAB) play the most important role in the fermentation. We investigated the natural population of LAB in whole-crop wheat (WCW) and examined the quality of whole-crop wheat silage (WCWS) with and without LAB inoculants. Two Lactobacillus plantarum subsp. plantarum strains, Zhengzhou University 1 (ZZU 1) selected from corn and forage and grass 1 (FG 1) from a commercial inoculant, were used as additives. The silages inoculated with LAB strains (ZZU 1 and FG 1) were better preserved than the control, with lower pH values (3.5 and 3.6, respectively) (p<0.05) and higher contents of lactic acid (37.5 and 34.0 g/kg of fresh matter (FM), respectively) (p<0.05) than the control. Sixty LAB strains were isolated from fresh material and WCWS without any LAB inoculation. These LAB strains were divided into the following four genera and six species based on their phenotypic, biochemical and phylogenetic characteristics: Leuconostoc pseudomesenteroides, Leuconostoc citreum, Weissella cibaria, Lactococcus lactis subsp. lactis, Lactobacillus buchneri, and Lactobacillus plantarum subsp. plantarum. However, the prevalent LAB, which was predominantly heterofermentative (66.7%), consisted of Leuconostoc pseudomesenteroides, Leuconostoc citreum, Weissella cibaria, and Lactobacillus buchneri. This study revealed that most of isolated LAB strains from control WCWS were heterofermentative and could not grow well at low pH condition; the selective inoculants of Lactobacillus strains, especially ZZU 1, could improve WCWS quality significantly. PMID:26104520

  18. 40 CFR 721.10629 - Fatty acids, tall-oil, reaction products with modified fatty acids and polyalkanolamines (generic).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Fatty acids, tall-oil, reaction... Fatty acids, tall-oil, reaction products with modified fatty acids and polyalkanolamines (generic). (a... generically as fatty acids, tall-oil, reaction products with modified fatty acids and polyalkanolamines (PMN...

  19. 40 CFR 721.10629 - Fatty acids, tall-oil, reaction products with modified fatty acids and polyalkanolamines (generic).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Fatty acids, tall-oil, reaction... Fatty acids, tall-oil, reaction products with modified fatty acids and polyalkanolamines (generic). (a... generically as fatty acids, tall-oil, reaction products with modified fatty acids and polyalkanolamines (PMN...

  20. Effect of baking process on added folic acid and endogenous folates stability in wheat and rye breads.

    PubMed

    Gujska, Elzbieta; Majewska, Katarzyna

    2005-06-01

    In Poland bread as a staple food both made from wheat and rye flour can be a potential product for future fortification with folic acid. The objective of the study was to examine the effect of fermentation and baking on added folic acid and some endogenous folates stability during breadmaking of rye and wheat breads. Breads were produced using the formulation containing enriched flour with 0.2 mg folic acid/100 g product, baker's yeast and additionally ascorbic acid for wheat bread and lactic acid for rye bread. Folates were extracted with Hepes/Ches buffer (pH = 7.85) followed by destruction of matrix by amylase and protease and deconjugation with rat serum conjugase. Affinity chromatography (FBP bovine milk) was used to purify and concentrate samples. The folates were separated by HPLC with C18 column and with a combination of fluorescence and UV detection. For both rye and wheat breads there was a decrease of folic acid from flour to bread stage. The total losses depend on baking process and ranged from 12 to 21%. Some changes in the level of different native folate forms during the stage of baking process were also observed.

  1. Properties of extruded vital wheat gluten sheets with sodium hydroxide and salicylic acid.

    PubMed

    Ullsten, N Henrik; Cho, Sung-Woo; Spencer, Gwen; Gällstedt, Mikael; Johansson, Eva; Hedenqvist, Mikael S

    2009-03-01

    This paper presents a novel approach to improve the barrier and mechanical properties of extruded glycerol-plasticized vital wheat gluten sheets. The sheets were extruded with a single screw extruder at alkaline conditions using 3-5 wt % NaOH. Salicylic acid (SA), known to improve the extrudability of wheat gluten, was also added alone or in combination with NaOH. Oxygen transmission rate and volatile mass measurements, tensile tests, protein solubility, glycerol migration, infrared spectroscopy, and electrophoresis were used to assess the properties of the extrudate. Electrophoresis showed that the gluten/glycerol sheet and the sheet with 3 wt % NaOH and 1 wt % SA contained the same building blocks in terms of proteins and protein subunits, although the protein solubility in these samples was different. The oxygen barrier, at dry conditions, was improved significantly with the addition of NaOH. On the other hand, the addition of salicylic acid yielded poorer barrier properties. The extrudate was placed on a blotting paper and its aging properties were investigated during the first 120 days. It was observed that the extrudate with 3 wt % NaOH had the most suitable combination of properties (low oxygen permeability, large strain at break, and relatively small aging-induced changes in mechanical properties); the reason is probably due to low plasticizer migration and an optimal protein aggregation/polymerization.

  2. Abscisic acid and late embryogenesis abundant protein profile changes in winter wheat under progressive drought stress.

    PubMed

    Vaseva, I I; Grigorova, B S; Simova-Stoilova, L P; Demirevska, K N; Feller, U

    2010-09-01

    Three varieties (cv. Pobeda, Katya and Sadovo) of winter wheat (Triticum aestivum), differing in their agronomic characteristics, were analysed during progressive soil water stress and recovery at early vegetation stages. Changes in abscisic acid content, SDS-PAGE and immunoblot profiles of proteins that remained soluble upon heating were monitored. Initially higher ABA content in control Pobeda and Katya corresponded to earlier expression of the studied late embryogenesis abundant (LEA) proteins. A combination of higher ABA content, early immunodetection of dehydrins, and a significant increase of WZY2 transcript levels were observed in drought-stressed leaves of the tolerant variety Katya. One-step RT-PCR analyses of some acidic dehydrin genes (WCOR410b, TADHN) documented their relatively constant high expression levels in leaves under drought stress during early vegetative development. Neutral WZY2 dehydrin, TaLEA2 and TaLEA3 transcripts accumulated gradually with increasing water deficit. Delayed expression of TaLEA2 and TaLEA3 genes was found in the least drought-tolerant wheat, Sadovo. The expression profile of WZY2 revealed two distinct and separate bands, suggesting alternative splicing, which altered as water stress increased.

  3. Barriers to application of genetically modified lactic acid bacteria.

    PubMed

    Verrips, C T; van den Berg, D J

    1996-10-01

    To increase the acceptability of food products containing genetically modified microorganisms it is necessary to provide in an early stage to the consumers that the product is safe and that the product provide a clear benefit to the consumer. To comply with the first requirement a systematic approach to analyze the probability that genetically modified lactic acid bacteria will transform other inhabitants of the gastro- intestinal (G/I) tract or that these lactic acid bacteria will pick up genetic information of these inhabitants has been proposed and worked out to some degree. From this analysis it is clear that reliable data are still missing to carry out complete risk assessment. However, on the basis of present knowledge, lactic acid bacteria containing conjugative plasmids should be avoided. Various studies show that consumers in developed countries will accept these products when they offer to them health or taste benefits or a better keepability. For the developing countries the biggest challenge for scientists is most likely to make indigenous fermented food products with strongly improved microbiological stability due to broad spectra bacteriocins produced by lactic acid bacteria. Moreover, these lactic acid bacteria may contribute to health.

  4. Wheat gluten-based renewable and biodegradable polymer materials with enhanced hydrophobicity by using epoxidized soybean oil as a modifier.

    PubMed

    Zhang, Xiaoqing; Do, My Dieu; Kurniawan, Lusiana; Qiao, Greg G

    2010-10-13

    Epoxidized soybean oil (ESO) was applied as an additive for wheat gluten (WG) to modify the properties of the renewable and biodegradable natural polymer materials. Optimum intermolecular interactions and crosslinking between ESO chains and the WG matrix were achieved under alkaline conditions. The WGESO materials were heterogeneous on a scale of 20-30 nm, but the homogeneity was improved upon increasing the amount of glycerol as a plasticizer in the materials. The combination of plasticization and crosslinking effects derived from ESO resulted in good retention in mechanical strength for the plasticized WGESO materials as compared to those without 10 wt% of mobile ESO additives. The hydrophobicity of the plasticized WG materials was also enhanced significantly by using the ESO additives.

  5. Fast and efficient benign oxidation of native wheat starch by acidic bromate under microwave activation.

    PubMed

    Komulainen, Sanna; Diaz, Estibaliz; Pursiainen, Jouni; Lajunen, Marja

    2013-02-15

    A simple oxidation of starch in water by bromate was substantially improved by microwave activation. In the oxidation of native wheat starch its advantages were the highly reduced need of oxidant from 1.05 to 0.1-0.25 equiv, shortened reaction time from 2 to 5.5h to 10 min, and moderate or high yields of oxidation content (degree of oxidation 0.22-0.55) of water-soluble products. Acidic treatment before the oxidation reaction promoted the carbonyl formation yielding higher contents of oxidized products (degree of oxidation 0.43-0.55) than without it (degree of oxidation 0.22-0.28). The pretreatment did not have similar effect on the amount of carboxyl groups. The oxidation route of acidic bromate oxidation of starch is discussed.

  6. Hydrolysis of organosolv wheat pulp in formic acid at high temperature for glucose production.

    PubMed

    Kupiainen, Laura; Ahola, Juha; Tanskanen, Juha

    2012-07-01

    Organosolv methods can be used to delignify lignocellulosic crop residues for pulp production or to pretreat them prior to enzymatic hydrolysis for bioethanol production. In this study, organic solvent was used as an acidic hydrolysis catalyst to produce glucose. Hydrolysis experiments were carried out in 5-20% formic acid at 180-220 °C. Wheat straw pulp delignified with a formicodeli™ method was used as a raw material. It was found that glucose yields from pulp are significantly higher than yields from microcrystalline cellulose, a model component for cellulose hydrolysis. The results indicate that cellulose hydrolysis of real fibers takes place more selectively to glucose than hydrolysis of microcrystalline cellulose particles does. The effect of the particle size on pulp hydrolysis was investigated, the crystallinity of hydrolyzed pulp was measured by XRD analysis, and the product distribution and its influence on the process was discussed. PMID:22609651

  7. Butyric acid fermentation from pretreated and hydrolysed wheat straw by an adapted Clostridium tyrobutyricum strain

    PubMed Central

    Baroi, G N; Baumann, I; Westermann, P; Gavala, H N

    2015-01-01

    Butyric acid is a valuable building-block for the production of chemicals and materials and nowadays it is produced exclusively from petroleum. The aim of this study was to develop a suitable and robust strain of Clostridium tyrobutyricum that produces butyric acid at a high yield and selectivity from lignocellulosic biomasses. Pretreated (by wet explosion) and enzymatically hydrolysed wheat straw (PHWS), rich in C6 and C5 sugars (71.6 and 55.4 g l−1 of glucose and xylose respectively), was used as substrate. After one year of serial selections, an adapted strain of C. tyrobutyricum was developed. The adapted strain was able to grow in 80% (v v−1) PHWS without addition of yeast extract compared with an initial tolerance to less than 10% PHWS and was able to ferment both glucose and xylose. It is noticeable that the adapted C. tyrobutyricum strain was characterized by a high yield and selectivity to butyric acid. Specifically, the butyric acid yield at 60–80% PHWS lie between 0.37 and 0.46 g g−1 of sugar, while the selectivity for butyric acid was as high as 0.9–1.0 g g−1 of acid. Moreover, the strain exhibited a robust response in regards to growth and product profile at pH 6 and 7. PMID:26230610

  8. Interactions between uptake of amino acids and inorganic nitrogen in wheat plants

    NASA Astrophysics Data System (ADS)

    Gioseffi, E.; de Neergaard, A.; Schjoerring, J. K.

    2011-11-01

    Soil-borne amino acids may constitute a nitrogen (N) source for plants in various terrestrial ecosystems but their importance for total N nutrition is unclear, particularly in nutrient-rich arable soils. One reason for this uncertainty is lack of information on how the absorption of amino acids by plant roots is affected by the simultaneous presence of inorganic N forms. The objective of the present study was to study absorption of glycine (Gly) and glutamine (Gln) by wheat roots and their interactions with nitrate (NO3-) and (NH4+) during uptake. The underlying hypothesis was that amino acids, when present in nutrient solution together with inorganic N, may lead to down-regulation of the inorganic N uptake. Amino acids were enriched with double-labelled 15N and 13C, while NO3- and NH4+ acquisition was determined by their rate of removal from the nutrient solution surrounding the roots. The uptake rates of NO3- and NH4+ did not differ from each other and were about twice as high as the uptake rate of organic N when the different N forms were supplied separately in concentrations of 2 mM. Nevertheless, replacement of 50 % of the inorganic N with organic N was able to restore the N uptake to the same level as that in the presence of only inorganic N. Co-provision of NO3- did not affect glycine uptake, while the presence of glycine down-regulated NO3- uptake. The ratio between 13C and 15N were lower in shoots than in roots and also lower than the theoretical values, reflecting higher C losses via respiratory processes compared to N losses. It is concluded that organic N can constitute a significant N-source for wheat plants and that there is an interaction between the uptake of inorganic and organic nitrogen.

  9. Interactions between uptake of amino acids and inorganic nitrogen in wheat plants

    NASA Astrophysics Data System (ADS)

    Gioseffi, E.; de Neergaard, A.; Schjoerring, J. K.

    2012-04-01

    Soil-borne amino acids may constitute a source of nitrogen (N) for plants in various terrestrial ecosystems but their importance for total N nutrition is unclear, particularly in nutrient-rich arable soils. One reason for this uncertainty is lack of information on how the absorption of amino acids by plant roots is affected by the simultaneous presence of inorganic N forms. The objective of the present study was to study absorption of glycine (Gly) and glutamine (Gln) by wheat roots and their interactions with nitrate (NO3-) and ammonium (NH4+) during uptake. The underlying hypothesis was that amino acids, when present in nutrient solution together with inorganic N, may lead to down-regulation of the inorganic N uptake, thereby resulting in similar total N uptake rates. Amino acids were enriched with double-labelled 15N and 13C, while NO3- and NH4+ acquisition was determined by their rate of removal from the nutrient solution surrounding the roots. The uptake rates of NO3- and NH4+ did not differ from each other and were generally about twice as high as the uptake rate of organic N when the different N forms were supplied separately in concentrations of 2 mM. Nevertheless, replacement of 50% of the inorganic N with organic N was able to restore the N uptake to the same level as that in the presence of only inorganic N. Co-provision of NO3- did not affect glycine uptake, while the presence of glycine down-regulated NO3- uptake. The ratio between 13C and 15N were lower in shoots than in roots and also lower than the theoretical values, reflecting higher C losses via respiratory processes compared to N losses. It is concluded that organic N can constitute a significant N-source for wheat plants and that there is an interaction between the uptake of inorganic and organic N.

  10. Alleviation of salt-induced oxidative damage by 5-aminolevulinic acid in wheat seedlings

    NASA Astrophysics Data System (ADS)

    Genişel, Mucip; Erdal, Serkan

    2016-04-01

    The aim of this study was to elucidate how 5-aminolevulinic acid (ALA), the precursor of chlorophyll compounds, affects the defence mechanisms of wheat seedlings induced by salt stress. To determine the possible stimulative effects of ALA against salinity, 11-day old wheat seedlings were sprayed with ALA at two different concentrations (10 and 20 mg.l-1) and then stressed by exposure to salt (150 mM NaCl). The salt stress led to significant changes in the antioxidant activity. While guaiacol peroxidase activity decreased, the activities of superoxide dismutase, catalase, and ascorbate peroxidase markedly increased under salt stress. Compared to the salt stress alone, the application of ALA beforehand further increased the activity of these enzymes. This study is the first time the effects of ALA have been monitored with regard to protein content and the isoenzyme profiles of the antioxidant enzymes. Although the salt stress reduced both the soluble protein content and protein band intensities, pre-treating with ALA significantly mitigated these stress-induced reductions. The data for the isoenzyme profiles of the antioxidant enzymes paralleled that of the ALA-induced increases in antioxidant activity. As a consequence of the high antioxidant activity in the seedlings pre-treated with ALA, the stress-induced elevations in the reactive oxygen species, superoxide anion, and hydrogen peroxide contents and lipid peroxidation levels were markedly diminished. Taken together, this data demonstrated that pre-treating with ALA confers resistance to salt stress by modulating the protein synthesis and antioxidant activity in wheat seedlings.

  11. Wheat bran biorefinery--an insight into the process chain for the production of lactic acid.

    PubMed

    Tirpanalan, Özge; Reisinger, Michael; Smerilli, Marina; Huber, Florian; Neureiter, Markus; Kneifel, Wolfgang; Novalin, Senad

    2015-03-01

    The present study investigates a wheat bran biorefinery including major processing steps pre-extraction, pre-treatment and lactic acid fermentation. Concerning the dry mass distribution, during the pre-extraction 32% of the feedstock was recovered, offering some perspectives for applications in food area. The pre-treatment (hydrothermal/enzymatic hydrolysis) of the remaining cake solubilized 34% of dry mass and led to a fermentable sugar concentration of 21g/L. The fermentation resulted in a lactic acid yield of 0.73g/g substrate. Concentrating the fermentation feed via nanofiltration did not improve the lactic acid productivity. Taking into account that Lactobacillus pentosus, a heterofermentative microorganism was used, the dry mass balance revealed a product yield of 47% (32% extract, 15% lactic acid). Based on a theoretical consideration involving a cellulolytic enzyme production (10% feedstock allocation) and lignin utilization, under optimized conditions a maximum product yield of around 80% (35% extract, 39% lactic acid, 6% lignin) could be expected.

  12. Rheological and functional properties of composite sweet potato - wheat dough as affected by transglutaminase and ascorbic acid.

    PubMed

    Ndayishimiye, Jean Bernard; Huang, Wei-Ning; Wang, Feng; Chen, Yong-Zheng; Letsididi, Rebaone; Rayas-Duarte, Patricia; Ndahetuye, Jean Baptiste; Tang, Xiao-Juan

    2016-02-01

    Effect of transglutaminase (TGM) and ascorbic acid (AA) on composite sweet potato - wheat dough functional and rheological properties was studied. Partial substitution of wheat flour with sweet potato flour at the level of 20 % significantly (P ≤ 0.05) reduced glutenin, gliadin, dough stability, protein weakening, storage modulus (G') and viscous modulus (G″). Mixolab revealed that both TGM and AA treated dough had stability and protein weakening closed to wheat dough (control), with TGM treated dough having the highest values. TGM Introduced new cross-link bonds as shown by the change of amino acid concentration, leading to an increase in storage modulus (G') and viscous modulus (G″), with G' being higher at all levels of TGM concentration. The opposite was observed for composite dough treated with AA as measured by controlled - stress rheometer. TGM treatment increased glutenin and gliadin content. Compared with the control, dough treated with AA exhibited high molecular weight of polymers than TGM treated dough. The results indicate that the TGM and AA modification of the mixolab and dynamic rheological characteristics (G' and G″) dependent on the changes of GMP, glutenin, gliadin and protein weakening in the composite dough. TGM and AA treatment could improve functional and rheological properties of sweet potato - wheat dough to levels that might be achieved with normal wheat bread. However, it's extremely important to optimize the concentrations of both additives to obtain the optimum response.

  13. Wheat bran promotes enrichment within the human colonic microbiota of butyrate-producing bacteria that release ferulic acid.

    PubMed

    Duncan, Sylvia H; Russell, Wendy R; Quartieri, Andrea; Rossi, Maddalena; Parkhill, Julian; Walker, Alan W; Flint, Harry J

    2016-07-01

    Cereal fibres such as wheat bran are considered to offer human health benefits via their impact on the intestinal microbiota. We show here by 16S rRNA gene-based community analysis that providing amylase-pretreated wheat bran as the sole added energy source to human intestinal microbial communities in anaerobic fermentors leads to the selective and progressive enrichment of a small number of bacterial species. In particular, OTUs corresponding to uncultured Lachnospiraceae (Firmicutes) related to Eubacterium xylanophilum and Butyrivibrio spp. were strongly enriched (by five to 160 fold) over 48 h in four independent experiments performed with different faecal inocula, while nine other Firmicutes OTUs showed > 5-fold enrichment in at least one experiment. Ferulic acid was released from the wheat bran during degradation but was rapidly converted to phenylpropionic acid derivatives via hydrogenation, demethylation and dehydroxylation to give metabolites that are detected in human faecal samples. Pure culture work using bacterial isolates related to the enriched OTUs, including several butyrate-producers, demonstrated that the strains caused substrate weight loss and released ferulic acid, but with limited further conversion. We conclude that breakdown of wheat bran involves specialist primary degraders while the conversion of released ferulic acid is likely to involve a multi-species pathway. PMID:26636660

  14. Exogenous salicylic acid enhances the resistance of wheat seedlings to hessian fly (Diptera: Cecidomyiidae) infestation under heat stress

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Heat stress exerts significant impact on plant-parasite interactions. Phytohormones, such as salicylic acid (SA) play important roles in plant defense against parasite attacks. Here we studied the impact of a combination of heat stress and exogenous SA on wheat (Triticum aestivum L.) plant resistanc...

  15. Wheat bran promotes enrichment within the human colonic microbiota of butyrate‐producing bacteria that release ferulic acid

    PubMed Central

    Duncan, Sylvia H.; Russell, Wendy R.; Quartieri, Andrea; Rossi, Maddalena; Parkhill, Julian; Flint, Harry J.

    2016-01-01

    Summary Cereal fibres such as wheat bran are considered to offer human health benefits via their impact on the intestinal microbiota. We show here by 16S rRNA gene‐based community analysis that providing amylase‐pretreated wheat bran as the sole added energy source to human intestinal microbial communities in anaerobic fermentors leads to the selective and progressive enrichment of a small number of bacterial species. In particular, OTUs corresponding to uncultured Lachnospiraceae (Firmicutes) related to E ubacterium xylanophilum and B utyrivibrio spp. were strongly enriched (by five to 160 fold) over 48 h in four independent experiments performed with different faecal inocula, while nine other Firmicutes OTUs showed > 5‐fold enrichment in at least one experiment. Ferulic acid was released from the wheat bran during degradation but was rapidly converted to phenylpropionic acid derivatives via hydrogenation, demethylation and dehydroxylation to give metabolites that are detected in human faecal samples. Pure culture work using bacterial isolates related to the enriched OTUs, including several butyrate‐producers, demonstrated that the strains caused substrate weight loss and released ferulic acid, but with limited further conversion. We conclude that breakdown of wheat bran involves specialist primary degraders while the conversion of released ferulic acid is likely to involve a multi‐species pathway. PMID:26636660

  16. Wheat bran promotes enrichment within the human colonic microbiota of butyrate-producing bacteria that release ferulic acid.

    PubMed

    Duncan, Sylvia H; Russell, Wendy R; Quartieri, Andrea; Rossi, Maddalena; Parkhill, Julian; Walker, Alan W; Flint, Harry J

    2016-07-01

    Cereal fibres such as wheat bran are considered to offer human health benefits via their impact on the intestinal microbiota. We show here by 16S rRNA gene-based community analysis that providing amylase-pretreated wheat bran as the sole added energy source to human intestinal microbial communities in anaerobic fermentors leads to the selective and progressive enrichment of a small number of bacterial species. In particular, OTUs corresponding to uncultured Lachnospiraceae (Firmicutes) related to Eubacterium xylanophilum and Butyrivibrio spp. were strongly enriched (by five to 160 fold) over 48 h in four independent experiments performed with different faecal inocula, while nine other Firmicutes OTUs showed > 5-fold enrichment in at least one experiment. Ferulic acid was released from the wheat bran during degradation but was rapidly converted to phenylpropionic acid derivatives via hydrogenation, demethylation and dehydroxylation to give metabolites that are detected in human faecal samples. Pure culture work using bacterial isolates related to the enriched OTUs, including several butyrate-producers, demonstrated that the strains caused substrate weight loss and released ferulic acid, but with limited further conversion. We conclude that breakdown of wheat bran involves specialist primary degraders while the conversion of released ferulic acid is likely to involve a multi-species pathway.

  17. Regulation of ion homeostasis by aminolevulinic acid in salt-stressed wheat seedlings

    NASA Astrophysics Data System (ADS)

    Türk, Hülya; Genişel, Mucip; Erdal, Serkan

    2016-04-01

    Salinity is regarded as a worldwide agricultural threat, as it seriously limits plant development and productivity. Salt stress reduces water uptake in plants by disrupting the osmotic balance of soil solution. In addition, it creates a damaged metabolic process by causing ion imbalance in cells. In this study, we aim to examine the negative effects of 5-aminolevulinic acid (ALA) (20 mg/l) on the ion balance in wheat seedling leaves exposed to salt stress (150 mM). Sodium is known to be highly toxic for plant cells at high concentrations, and is significantly increased by salt stress. However, it can be reduced by combined application of ALA and salt, compared to salt application alone. On the other hand, while the K+/Na+ ratio was reduced by salt stress, ALA application changed this ratio in favor of K+. Manganese, iron, and copper were also able to reduce stress. However, ALA pre-treatment resulted in mineral level increments. Conversely, the stress-induced rise in magnesium, potassium, calcium, phosphorus, zinc, and molybdenum were further improved by ALA application. These data clearly show that ALA has an important regulatory effect of ion balance in wheat leaves.

  18. Combination of extrusion and cyclodextrin glucanotransferase treatment to modify wheat flours functionality.

    PubMed

    Román, Laura; Dura, Ángela; Martínez, Mario M; Rosell, Cristina M; Gómez, Manuel

    2016-05-15

    This research aims to vary functional properties of native and extruded wheat flours combining cyclodextrin glucanotransferase and extrusion treatments. The level of released cyclodextrins (CD) was assessed, besides the microstructure, crystallinity, pasting properties and starch hydrolysis of the flours. Photomicrographs of enzymatically treated flours suggested the production of fragile structures that broke easily. Enzymatic hydrolysis was significantly higher in extruded flours, as confirmed the CD levels, being predominant the γ-CD followed by α-CD, whereas very low β-CD values were obtained probably due to the formation of CD-lipid complexes, as suggested X-ray diffractometry results. Both extruded and native samples showed very low viscosity and flat pasting profile consequence of the enzyme hydrolytic activity on the starch chains. Enzymatically treated flours (native and extruded) showed higher hydrolysis rates at the early hydrolysis stage, and extruded flours exhibited higher fractal exponent h in agreement with the extended crystalline structures resulting from enzymatic treatment. PMID:26775973

  19. 40 CFR 721.10089 - Modified salicylic acid, zirconium complex (generic).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Modified salicylic acid, zirconium... Specific Chemical Substances § 721.10089 Modified salicylic acid, zirconium complex (generic). (a) Chemical... as modified salicylic acid, zirconium complex (PMN P-00-552) is subject to reporting under...

  20. 40 CFR 721.10089 - Modified salicylic acid, zirconium complex (generic).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Modified salicylic acid, zirconium... Specific Chemical Substances § 721.10089 Modified salicylic acid, zirconium complex (generic). (a) Chemical... as modified salicylic acid, zirconium complex (PMN P-00-552) is subject to reporting under...

  1. 40 CFR 721.10089 - Modified salicylic acid, zirconium complex (generic).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Modified salicylic acid, zirconium... Specific Chemical Substances § 721.10089 Modified salicylic acid, zirconium complex (generic). (a) Chemical... as modified salicylic acid, zirconium complex (PMN P-00-552) is subject to reporting under...

  2. 40 CFR 721.10089 - Modified salicylic acid, zirconium complex (generic).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Modified salicylic acid, zirconium... Specific Chemical Substances § 721.10089 Modified salicylic acid, zirconium complex (generic). (a) Chemical... as modified salicylic acid, zirconium complex (PMN P-00-552) is subject to reporting under...

  3. 40 CFR 721.10089 - Modified salicylic acid, zirconium complex (generic).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Modified salicylic acid, zirconium... Specific Chemical Substances § 721.10089 Modified salicylic acid, zirconium complex (generic). (a) Chemical... as modified salicylic acid, zirconium complex (PMN P-00-552) is subject to reporting under...

  4. Effects of Azospirillum brasilense with genetically modified auxin biosynthesis gene ipdC upon the diversity of the indigenous microbiota of the wheat rhizosphere.

    PubMed

    Baudoin, Ezékiel; Lerner, Anat; Mirza, M Sajjad; El Zemrany, Hamdy; Prigent-Combaret, Claire; Jurkevich, Edouard; Spaepen, Stijn; Vanderleyden, Jos; Nazaret, Sylvie; Okon, Yaacov; Moënne-Loccoz, Yvan

    2010-04-01

    The phytostimulatory properties of Azospirillum inoculants, which entail production of the phytohormone indole-3-acetic acid (IAA), can be enhanced by genetic means. However, it is not known whether this could affect their interactions with indigenous soil microbes. Here, wheat seeds were inoculated with the wild-type strain Azospirillum brasilense Sp245 or one of three genetically modified (GM) derivatives and grown for one month. The GM derivatives contained a plasmid vector harboring the indole-3-pyruvate/phenylpyruvate decarboxylase gene ipdC (IAA production) controlled either by the constitutive promoter PnptII or the root exudate-responsive promoter PsbpA, or by an empty vector (GM control). All inoculants displayed equal rhizosphere population densities. Only inoculation with either ipdC construct increased shoot biomass compared with the non-inoculated control. At one month after inoculation, automated ribosomal intergenic spacer analysis (ARISA) revealed that the effect of the PsbpA construct on bacterial community structure differed from that of the GM control, which was confirmed by 16S rDNA-based denaturing gradient gel electrophoresis (DGGE). The fungal community was sensitive to inoculation with the PsbpA construct and especially the GM control, based on ARISA data. Overall, fungal and bacterial communities displayed distinct responses to inoculation of GM A. brasilense phytostimulators, whose effects could differ from those of the wild-type.

  5. Comparative characterization of the deamidation of carboxylic acid deamidated wheat gluten by altering the processing conditions.

    PubMed

    Liao, Lan; Han, Xueyue; Chen, Lin-Ping; Ni, Li; Liu, Zhi-Bin; Zhang, Wen; Chen, Qing

    2016-11-01

    The physicochemical, structural and functional properties of citric-acid-deamidated wheat gluten at controlled degrees of deamidation (25%, 40% and 55%), which were obtained by using different acid concentrations (3.93×10(-5), 3.14×10(-3) and 2.36×10(-2)mol/L) and temperatures (70°C 2h, 90°C 1h and 110°C 40min), were compared. Various deamidation processing conditions leading to the same degree of deamidation resulted in proteins with different physicochemical and structural characteristics, as indicted by the degree of hydrolysis, Z-potential, surface hydrophobicity, particle size, SDS-PAGE results, SEC-HPLC results, intrinsic fluorescence and FTIR spectra. Agglomerative hierarchical clustering analysis and principal component analysis qualitatively indicated a significant effect of pH on protein deamidation. Three samples at 40% deamidation, which were produced by a moderate acid concentration, showed the best emulsifying and foaming properties. Processes conducted at greater than 90°C causing protein aggregation and at a high acid concentration rupturing peptide bonds, impaired protein quality. These findings demonstrated that a limited amount of H(+) could function well in the catalysis of the deamidation of amide groups without an excess of H(+), which hydrolyses peptide bonds in a stronger hydrothermal treatment.

  6. [Response of POD and CAT during seeds of rice, wheat and rape germination on acid rain stress].

    PubMed

    Wang, Li-hong; Huang, Xiao-hua; Zhou, Qing

    2005-11-01

    The effects of simulated acid rain (pH 2.5 - 5.0) on the activities of POD and CAT were investigated during germination of rice (O. sativa), wheat (T. aestivum) and rape (B. chinensis var. oleifera) seeds. Compared with the control (CK), the amplitude of the change in the activity of CAT and POD is that rice (28.8%, 31.7%) < wheat (34.7%, 48.3%) < rape (79.3%, 50.0%), respectively. The pH significantly different (p < 0.05) from CK follows the order: rice (3.5) > wheat (4.0) > rape (5.0). All of these revealed that the ability of resisting acid rain stress is that rice is stronger than wheat and rape is the worst. Under the same condition, the amplitude of the change in the activity of CAT is more sensitivity toward acid rain stress than that of POD. The difference in free radicals removed by these 3 species is one of the reasons why the germinating indexes behaved differently.

  7. Nitrate removal using natural clays modified by acid thermoactivation

    NASA Astrophysics Data System (ADS)

    Mena-Duran, C. J.; Sun Kou, M. R.; Lopez, T.; Azamar-Barrios, J. A.; Aguilar, D. H.; Domínguez, M. I.; Odriozola, J. A.; Quintana, P.

    2007-04-01

    Groundwater pollution by nitrates is a widespread problem in many locations in the world. The underground aquatic mantle of the Peninsula of Yucatan is highly vulnerable due to its karstic nature. Adsorption methods are a good choice for nitrate elimination. In this work, a natural calcium bentonite was modified by acid thermoactivation with HCl and H 2SO 4, and tested as a media for nitrate removal in an aqueous solution. The nitrate concentration in the solution was measured by FT-IR, using the Lambert-Beer law. Clay characterization was carried out by X-ray diffraction and FT-IR spectroscopy; surface area was measured by the BET method.

  8. Impact of acid and alkaline pretreatments on the molecular network of wheat gluten and on the mechanical properties of compression-molded glassy wheat gluten bioplastics.

    PubMed

    Jansens, Koen J A; Lagrain, Bert; Brijs, Kristof; Goderis, Bart; Smet, Mario; Delcour, Jan A

    2013-10-01

    Wheat gluten can be converted into rigid biobased materials by high-temperature compression molding at low moisture contents. During molding, a cross-linked protein network is formed. This study investigated the effect of mixing gluten with acid/alkali in 70% ethanol at ambient temperature for 16 h followed by ethanol removal, freeze-drying, and compression molding at 130 and 150 °C on network formation and on types of cross-links formed. Alkaline pretreatment (0-100 mmol/L sodium hydroxide or 25 mmol/L potassium hydroxide) strongly affected gluten cross-linking, whereas acid pretreatment (0-25 mmol/L sulfuric acid or 25 mmol/L hydrochloric acid) had limited effect on the gluten network. Molded alkaline-treated gluten showed enhanced cross-linking but also degradation when treated with high alkali concentrations, whereas acid treatment reduced gluten cross-linking. β-Elimination of cystine and lanthionine formation occurred more pronouncedly at higher alkali concentrations. In contrast, formation of disulfide and nondisulfide cross-links during molding was hindered in acid-pretreated gluten. Bioplastic strength was higher for alkali than for acid-pretreated samples, whereas the flexural modulus was only slightly affected by either alkaline or acid pretreatment. Apparently, the ratio of disulfide to nondisulfide cross-links did not affect the mechanical properties of rigid gluten materials.

  9. Impact of acid and alkaline pretreatments on the molecular network of wheat gluten and on the mechanical properties of compression-molded glassy wheat gluten bioplastics.

    PubMed

    Jansens, Koen J A; Lagrain, Bert; Brijs, Kristof; Goderis, Bart; Smet, Mario; Delcour, Jan A

    2013-10-01

    Wheat gluten can be converted into rigid biobased materials by high-temperature compression molding at low moisture contents. During molding, a cross-linked protein network is formed. This study investigated the effect of mixing gluten with acid/alkali in 70% ethanol at ambient temperature for 16 h followed by ethanol removal, freeze-drying, and compression molding at 130 and 150 °C on network formation and on types of cross-links formed. Alkaline pretreatment (0-100 mmol/L sodium hydroxide or 25 mmol/L potassium hydroxide) strongly affected gluten cross-linking, whereas acid pretreatment (0-25 mmol/L sulfuric acid or 25 mmol/L hydrochloric acid) had limited effect on the gluten network. Molded alkaline-treated gluten showed enhanced cross-linking but also degradation when treated with high alkali concentrations, whereas acid treatment reduced gluten cross-linking. β-Elimination of cystine and lanthionine formation occurred more pronouncedly at higher alkali concentrations. In contrast, formation of disulfide and nondisulfide cross-links during molding was hindered in acid-pretreated gluten. Bioplastic strength was higher for alkali than for acid-pretreated samples, whereas the flexural modulus was only slightly affected by either alkaline or acid pretreatment. Apparently, the ratio of disulfide to nondisulfide cross-links did not affect the mechanical properties of rigid gluten materials. PMID:24016229

  10. Induced Reporter Gene Activity, Enhanced Stress Resistance, and Competitive Ability of a Genetically Modified Pseudomonas fluorescens Strain Released into a Field Plot Planted with Wheat

    PubMed Central

    Van Overbeek, L. S.; Van Veen, J. A.; Van Elsas, J. D.

    1997-01-01

    induction of reporter gene expression in strain RIWE8 in the wheat rhizosphere, the data indicated that there were no great differences in the ecological properties in soil between the lacZ-modified and parental strains. PMID:16535606

  11. Influence of salinity and temperature on uptake of perfluorinated carboxylic acids (PFCAs) by hydroponically grown wheat (Triticum aestivum L.).

    PubMed

    Zhao, Hongxia; Qu, Baocheng; Guan, Yue; Jiang, Jingqiu; Chen, Xiuying

    2016-01-01

    Perfluoroalkyl substances (PFASs) have recently attracted increasing concerns due to their ubiquitous existence, adverse effects and persistence in environment. This study employed four perfluorinated carboxylic acids (PFCAs) to examine effects of salinity and temperature on the PFAS uptake in wheat, one of the major crops in the North China Plain. Wheat plants were grown in the spiked-PFCA hydroponic culture system at different salinities and temperatures. As expected, salinity and temperature significantly impacted the root uptake and translocation of wheat to four PFCAs, and the concentrations for each of PFCAs in wheat root and shoot increased with increasing salinity and temperature, respectively. PFCA concentrations at high salinity or high temperature were up to thrice those found at low salinity or low temperature. Except for perfluorobutanoic acid, the amount of PFCAs in root was always higher than that in shoot at the ranges of salinity and temperature tested. Additionally salinity and temperature were also capable of influencing the transfer factors (TFs) of four PFCAs, and significant increase was observed in the TFs in response to the increases in salinity and temperature.

  12. Influence of salinity and temperature on uptake of perfluorinated carboxylic acids (PFCAs) by hydroponically grown wheat (Triticum aestivum L.).

    PubMed

    Zhao, Hongxia; Qu, Baocheng; Guan, Yue; Jiang, Jingqiu; Chen, Xiuying

    2016-01-01

    Perfluoroalkyl substances (PFASs) have recently attracted increasing concerns due to their ubiquitous existence, adverse effects and persistence in environment. This study employed four perfluorinated carboxylic acids (PFCAs) to examine effects of salinity and temperature on the PFAS uptake in wheat, one of the major crops in the North China Plain. Wheat plants were grown in the spiked-PFCA hydroponic culture system at different salinities and temperatures. As expected, salinity and temperature significantly impacted the root uptake and translocation of wheat to four PFCAs, and the concentrations for each of PFCAs in wheat root and shoot increased with increasing salinity and temperature, respectively. PFCA concentrations at high salinity or high temperature were up to thrice those found at low salinity or low temperature. Except for perfluorobutanoic acid, the amount of PFCAs in root was always higher than that in shoot at the ranges of salinity and temperature tested. Additionally salinity and temperature were also capable of influencing the transfer factors (TFs) of four PFCAs, and significant increase was observed in the TFs in response to the increases in salinity and temperature. PMID:27186505

  13. Permeability of membranes to amino acids and modified amino acids: mechanisms involved in translocation

    NASA Technical Reports Server (NTRS)

    Chakrabarti, A. C.; Deamer, D. W. (Principal Investigator); Miller, S. L. (Principal Investigator)

    1994-01-01

    The amino acid permeability of membranes is of interest because they are one of the key solutes involved in cell function. Membrane permeability coefficients (P) for amino acid classes, including neutral, polar, hydrophobic, and charged species, have been measured and compared using a variety of techniques. Decreasing lipid chain length increased permeability slightly (5-fold), while variations in pH had only minor effects on the permeability coefficients of the amino acids tested in liposomes. Increasing the membrane surface charge increased the permeability of amino acids of the opposite charge, while increasing the cholesterol content decreased membrane permeability. The permeability coefficients for most amino acids tested were surprisingly similar to those previously measured for monovalent cations such as sodium and potassium (approximately 10(-12)-10(-13) cm s-1). This observation suggests that the permeation rates for the neutral, polar and charged amino acids are controlled by bilayer fluctuations and transient defects, rather than partition coefficients and Born energy barriers. Hydrophobic amino acids were 10(2) more permeable than the hydrophilic forms, reflecting their increased partition coefficient values. External pH had dramatic effects on the permeation rates for the modified amino acid lysine methyl ester in response to transmembrane pH gradients. It was established that lysine methyl ester and other modified short peptides permeate rapidly (P = 10(-2) cm s-1) as neutral (deprotonated) molecules. It was also shown that charge distributions dramatically alter permeation rates for modified di-peptides. These results may relate to the movement of peptides through membranes during protein translocation and to the origin of cellular membrane transport on the early Earth.

  14. Sourdough lactic acid bacteria: exploration of non-wheat cereal-based fermentation.

    PubMed

    Coda, Rossana; Cagno, Raffaella Di; Gobbetti, Marco; Rizzello, Carlo Giuseppe

    2014-02-01

    Cereal-based foods represent a very important source of biological as well as of cultural diversity, as testified by the wide range of derived fermented products. A trend that is increasingly attracting bakery industries as well as consumers is the use of non-conventional flours for the production of novel products, characterised by peculiar flavour and better nutritional value. Lactic acid bacteria microbiota of several non-wheat cereals and pseudo-cereals has been recently deeply investigated with the aim of studying the biodiversity and finding starter cultures for sourdough fermentation. Currently, the use of ancient or ethnic grains is mainly limited to traditional typical foods and the bread making process is not well standardised with consequent negative effects on the final properties. The challenge in fermenting such grains is represented by the necessity to combine good technology and sensory properties with nutritional/health benefits. The choice of the starter cultures has a critical impact on the final quality of cereal-based products, and strains that dominate and outcompete contaminants should be applied for specific sourdough fermentations. In this sense, screening and characterisation of the lactic acid bacteria microbiota is very useful in the improvement of a peculiar flour, from both a nutritional and technological point of view.

  15. [Effect of salicylic acid on water potential, ethylene secretion and activity of antioxidative processes in the winter wheat leaves under drought conditions].

    PubMed

    Mamenko, T P; Iaroshenko, O A

    2009-01-01

    Effect of plants treatment by salicylic acid on the water potential, ethylene emission, intensity of lipid peroxidation oxidation and enzymatic antioxidative activity in the leaves with contrasting drought-resistance of winter wheat cultivars was investigated. It is ascertain, that the treatment of plants by salicylic acid contributes to a decrease of water loss and intensity of lipid peroxidation, to an increase of ethylene synthesis and peroxidase, catalase, superoxide dismutase activity in the winter wheat leaves under drought conditions.

  16. [Compatibility of a novel ethylenediamine modified polylactic acid with osteoblasts].

    PubMed

    Su, Aihua; Wang, Yuanliang; Luo, Yanfeng; Wu, Keda

    2005-08-01

    Biocompatibility of a newly developed ethylenediamine modified poly (DL-latic acid) (EMPLA) with osteoblasts was investigated by means of cell morphology and cell proliferation. Films of PLA and EMPLA were made by solvent casting. Osteoblasts obtained from crania of neonatal Wistar rats were cultured on surfaces of PLA and EMPLA, with glass as control. The cell morphology was observed by phase contrast microscope and the cell proliferation was determined by MTT assay. The morphology observations revealed that the osteoblasts cultured on EMPLA spread wider than those on PLA, and much more cells were confluent on EMPLA, compared to those on PLA and glass. The growth curves showed the osteoblasts on EMPLA grew faster than did those on PLA and glass. The results exhibited that the biocompatibility of EMPLA with osteoblasts is better than that of PLA and glass, which suggested wide applications of EMPLA in biomedical area, especially in tissue engineering. PMID:16156255

  17. Lactic Acid Bacteria in Durum Wheat Flour Are Endophytic Components of the Plant during Its Entire Life Cycle

    PubMed Central

    Minervini, Fabio; Celano, Giuseppe; Lattanzi, Anna; Tedone, Luigi; De Mastro, Giuseppe; De Angelis, Maria

    2015-01-01

    This study aimed at assessing the dynamics of lactic acid bacteria and other Firmicutes associated with durum wheat organs and processed products. 16S rRNA gene-based high-throughput sequencing showed that Lactobacillus, Streptococcus, Enterococcus, and Lactococcus were the main epiphytic and endophytic genera among lactic acid bacteria. Bacillus, Exiguobacterium, Paenibacillus, and Staphylococcus completed the picture of the core genus microbiome. The relative abundance of each lactic acid bacterium genus was affected by cultivars, phenological stages, other Firmicutes genera, environmental temperature, and water activity (aw) of plant organs. Lactobacilli, showing the highest sensitivity to aw, markedly decreased during milk development (Odisseo) and physiological maturity (Saragolla). At these stages, Lactobacillus was mainly replaced by Streptococcus, Lactococcus, and Enterococcus. However, a key sourdough species, Lactobacillus plantarum, was associated with plant organs during the life cycle of Odisseo and Saragolla wheat. The composition of the sourdough microbiota and the overall quality of leavened baked goods are also determined throughout the phenological stages of wheat cultivation, with variations depending on environmental and agronomic factors. PMID:26187970

  18. Amino acid production from rice straw and wheat bran hydrolysates by recombinant pentose-utilizing Corynebacterium glutamicum.

    PubMed

    Gopinath, Vipin; Meiswinkel, Tobias M; Wendisch, Volker F; Nampoothiri, K Madhavan

    2011-12-01

    Corynebacterium glutamicum wild type lacks the ability to utilize the pentose fractions of lignocellulosic hydrolysates, but it is known that recombinants expressing the araBAD operon and/or the xylA gene from Escherichia coli are able to grow with the pentoses xylose and arabinose as sole carbon sources. Recombinant pentose-utilizing strains derived from C. glutamicum wild type or from the L-lysine-producing C. glutamicum strain DM1729 utilized arabinose and/or xylose when these were added as pure chemicals to glucose-based minimal medium or when they were present in acid hydrolysates of rice straw or wheat bran. The recombinants grew to higher biomass concentrations and produced more L-glutamate and L-lysine, respectively, than the empty vector control strains, which utilized the glucose fraction. Typically, arabinose and xylose were co-utilized by the recombinant strains along with glucose either when acid rice straw and wheat bran hydrolysates were used or when blends of pure arabinose, xylose, and glucose were used. With acid hydrolysates growth, amino acid production and sugar consumption were delayed and slower as compared to media with blends of pure arabinose, xylose, and glucose. The ethambutol-triggered production of up to 93 ± 4 mM L-glutamate by the wild type-derived pentose-utilizing recombinant and the production of up to 42 ± 2 mM L-lysine by the recombinant pentose-utilizing lysine producer on media containing acid rice straw or wheat bran hydrolysate as carbon and energy source revealed that acid hydrolysates of agricultural waste materials may provide an alternative feedstock for large-scale amino acid production. PMID:21796382

  19. Nanostructure Modified Microelectrode for Electrochemical Detection of Dopamine with Ascorbic Acid and Uric Acid.

    PubMed

    Kim, Kyeong-Jun; Choi, Jin-Ha; Pyo, Su-Hyun; Yun, Kwang-Seok; Lee, Ji-Young; Choi, Jeong-Woo; Oh, Byung-Keun

    2016-03-01

    Dopamine (DA) is one kind of neurotransmitter in central nervous system which is indicator of neural disease. For this reason, determination of DA concentration in central nervous system is very important for early diagnosis of neural disease. In this study, we designed micro electrode array and fabricated by MEMS technology. Furthermore, we fabricated 3-D conducting nanostructure on electrode surface for enhanced sensitivity and selectivity due to increased surface area. Compared with macro and normal micro electrode, the 3-D nanostructure modified micro electrode shows better electrical performance. These surface modified pin type electrode was applied to detect low concentration of DA and successfully detect various concentration of DA from 100 μM to 1 μM with linear relationship in the presence of ascorbic acid and uric acid. From these results, our newly designed electrode shows possibility to be applied as brain biosensor for neural disease diagnosis such as Parkinson's diseases. PMID:27455760

  20. Prebiotic content of bread prepared with flour from immature wheat grain and selected dextran-producing lactic acid bacteria.

    PubMed

    Pepe, Olimpia; Ventorino, Valeria; Cavella, Silvana; Fagnano, Massimo; Brugno, Rachele

    2013-06-01

    In the last few years the need to produce food with added value has fueled the search for new ingredients and health-promoting compounds. In particular, to improve the quality of bakery products with distinct nutritional properties, the identification of new raw materials, appropriate technologies, and specific microbial strains is necessary. In this study, different doughs were prepared, with 10% and 20% flour from immature wheat grain blended with type "0 America" wheat flour. Immature flour was obtained from durum wheat grains harvested 1 to 2 weeks after anthesis. Doughs were obtained by both the straight-dough and sourdough processes. Two selected exopolysaccharide-producing strains of lactic acid bacteria (LAB), Leuconostoc lactis A95 and Lactobacillus curvatus 69B2, were used as starters. Immature flour contained 2.21 g/100 g (dry weight) of fructo-oligosaccharides. Twenty percent immature flour in dough resulted in a shorter leavening time (4.23 ± 0.03 h) than with the control and dough with 10% immature flour. The total titratable acidity of sourdough with 20% immature flour was higher (12.75 ± 0.15 ml 0.1 N NaOH) than in the control and sourdough with 10% immature wheat flour (9.20 ml 0.1 N NaOH). Molecular analysis showed that all samples contained three LAB species identified as L. lactis, L. curvatus, and Pediococcus acidilactici. A larger amount of exopolysaccharide was found in sourdough obtained with 20% immature flour (5.33 ± 0.032 g/kg), positively influencing the exopolysaccharide content of the bread prepared by the sourdough process (1.70 ± 0.03 g/kg). The addition of 20% immature flour also led to a greater presence of fructo-oligosaccharides in the bread (900 mg/100 g dry weight), which improved its nutritional characteristics. While bread volume decreased as the concentration of immature wheat flour increased, its mechanical characteristics (stress at a strain of 30%) were the same in all samples obtained with different percentages of

  1. Prebiotic Content of Bread Prepared with Flour from Immature Wheat Grain and Selected Dextran-Producing Lactic Acid Bacteria

    PubMed Central

    Ventorino, Valeria; Cavella, Silvana; Fagnano, Massimo; Brugno, Rachele

    2013-01-01

    In the last few years the need to produce food with added value has fueled the search for new ingredients and health-promoting compounds. In particular, to improve the quality of bakery products with distinct nutritional properties, the identification of new raw materials, appropriate technologies, and specific microbial strains is necessary. In this study, different doughs were prepared, with 10% and 20% flour from immature wheat grain blended with type “0 America” wheat flour. Immature flour was obtained from durum wheat grains harvested 1 to 2 weeks after anthesis. Doughs were obtained by both the straight-dough and sourdough processes. Two selected exopolysaccharide-producing strains of lactic acid bacteria (LAB), Leuconostoc lactis A95 and Lactobacillus curvatus 69B2, were used as starters. Immature flour contained 2.21 g/100 g (dry weight) of fructo-oligosaccharides. Twenty percent immature flour in dough resulted in a shorter leavening time (4.23 ± 0.03 h) than with the control and dough with 10% immature flour. The total titratable acidity of sourdough with 20% immature flour was higher (12.75 ± 0.15 ml 0.1 N NaOH) than in the control and sourdough with 10% immature wheat flour (9.20 ml 0.1 N NaOH). Molecular analysis showed that all samples contained three LAB species identified as L. lactis, L. curvatus, and Pediococcus acidilactici. A larger amount of exopolysaccharide was found in sourdough obtained with 20% immature flour (5.33 ± 0.032 g/kg), positively influencing the exopolysaccharide content of the bread prepared by the sourdough process (1.70 ± 0.03 g/kg). The addition of 20% immature flour also led to a greater presence of fructo-oligosaccharides in the bread (900 mg/100 g dry weight), which improved its nutritional characteristics. While bread volume decreased as the concentration of immature wheat flour increased, its mechanical characteristics (stress at a strain of 30%) were the same in all samples obtained with different percentages

  2. Label Distribution in Tissues of Wheat Seedlings Cultivated with Tritium-Labeled Leonardite Humic Acid

    NASA Astrophysics Data System (ADS)

    Kulikova, Natalia A.; Abroskin, Dmitry P.; Badun, Gennady A.; Chernysheva, Maria G.; Korobkov, Viktor I.; Beer, Anton S.; Tsvetkova, Eugenia A.; Senik, Svetlana V.; Klein, Olga I.; Perminova, Irina V.

    2016-06-01

    Humic substances (HS) play important roles in the biotic-abiotic interactions of the root plant and soil contributing to plant adaptation to external environments. However, their mode of action on plants remains largely unknown. In this study the HS distribution in tissues of wheat seedlings was examined using tritium-labeled humic acid (HA) derived from leonardite (a variety of lignites) and microautoradiography (MAR). Preferential accumulation of labeled products from tritiated HA was found in the roots as compared to the shoots, and endodermis was shown to be the major control point for radial transport of label into vascular system of plant. Tritium was also found in the stele and xylem tissues indicating that labeled products from tritiated HA could be transported to shoot tissues via the transpiration stream. Treatment with HA lead to an increase in the content of polar lipids of photosynthetic membranes. The observed accumulation of labeled HA products in root endodermis and positive impact on lipid synthesis are consistent with prior reported observations on physiological effects of HS on plants such as enhanced growth and development of lateral roots and improvement/repairs of the photosynthetic status of plants under stress conditions.

  3. Label Distribution in Tissues of Wheat Seedlings Cultivated with Tritium-Labeled Leonardite Humic Acid.

    PubMed

    Kulikova, Natalia A; Abroskin, Dmitry P; Badun, Gennady A; Chernysheva, Maria G; Korobkov, Viktor I; Beer, Anton S; Tsvetkova, Eugenia A; Senik, Svetlana V; Klein, Olga I; Perminova, Irina V

    2016-01-01

    Humic substances (HS) play important roles in the biotic-abiotic interactions of the root plant and soil contributing to plant adaptation to external environments. However, their mode of action on plants remains largely unknown. In this study the HS distribution in tissues of wheat seedlings was examined using tritium-labeled humic acid (HA) derived from leonardite (a variety of lignites) and microautoradiography (MAR). Preferential accumulation of labeled products from tritiated HA was found in the roots as compared to the shoots, and endodermis was shown to be the major control point for radial transport of label into vascular system of plant. Tritium was also found in the stele and xylem tissues indicating that labeled products from tritiated HA could be transported to shoot tissues via the transpiration stream. Treatment with HA lead to an increase in the content of polar lipids of photosynthetic membranes. The observed accumulation of labeled HA products in root endodermis and positive impact on lipid synthesis are consistent with prior reported observations on physiological effects of HS on plants such as enhanced growth and development of lateral roots and improvement/repairs of the photosynthetic status of plants under stress conditions. PMID:27350412

  4. Label Distribution in Tissues of Wheat Seedlings Cultivated with Tritium-Labeled Leonardite Humic Acid

    PubMed Central

    Kulikova, Natalia A.; Abroskin, Dmitry P.; Badun, Gennady A.; Chernysheva, Maria G.; Korobkov, Viktor I.; Beer, Anton S.; Tsvetkova, Eugenia A.; Senik, Svetlana V.; Klein, Olga I.; Perminova, Irina V.

    2016-01-01

    Humic substances (HS) play important roles in the biotic-abiotic interactions of the root plant and soil contributing to plant adaptation to external environments. However, their mode of action on plants remains largely unknown. In this study the HS distribution in tissues of wheat seedlings was examined using tritium-labeled humic acid (HA) derived from leonardite (a variety of lignites) and microautoradiography (MAR). Preferential accumulation of labeled products from tritiated HA was found in the roots as compared to the shoots, and endodermis was shown to be the major control point for radial transport of label into vascular system of plant. Tritium was also found in the stele and xylem tissues indicating that labeled products from tritiated HA could be transported to shoot tissues via the transpiration stream. Treatment with HA lead to an increase in the content of polar lipids of photosynthetic membranes. The observed accumulation of labeled HA products in root endodermis and positive impact on lipid synthesis are consistent with prior reported observations on physiological effects of HS on plants such as enhanced growth and development of lateral roots and improvement/repairs of the photosynthetic status of plants under stress conditions. PMID:27350412

  5. Effect of environment on the free and peptide amino acids in rice, wheat, and soybeans.

    PubMed

    Ahn, D J; Adeola, O; Nielsen, S S

    2001-01-01

    Controlled environments (CE) in which light, carbon dioxide, and nutrients are regulated are known to affect the chemical composition of plants. Controlled Ecological Life Support System (CELSS) environments are required for a Mars or lunar base where food resupply is both impractical and risky. Astronauts in a CELSS would need to grow and process edible biomass into foods. The complete nature of the changes in chemical composition of CE-grown plants is unknown but must be determined to ensure a safe and nutritionally adequate diet. In this article, we report the changes that occur in free and peptide-bound amino acids (AA) of select CELSS crops (rice, wheat, and soybean) grown in the field or in CE. The nonnitrate nonprotein nitrogen fraction was extracted and then analyzed for free and peptide AA. For grain or seeds, AA levels tended to increase from field to CE conditions; however, for vegetative material, AA levels remained the same or decreased from field to CE conditions. As such compositional changes are identified, researchers will be better able to design safe and nutritious diets for astronauts while minimizing needed energy and other resources.

  6. Effect of environment on the free and peptide amino acids in rice, wheat, and soybeans.

    PubMed

    Ahn, D J; Adeola, O; Nielsen, S S

    2001-01-01

    Controlled environments (CE) in which light, carbon dioxide, and nutrients are regulated are known to affect the chemical composition of plants. Controlled Ecological Life Support System (CELSS) environments are required for a Mars or lunar base where food resupply is both impractical and risky. Astronauts in a CELSS would need to grow and process edible biomass into foods. The complete nature of the changes in chemical composition of CE-grown plants is unknown but must be determined to ensure a safe and nutritionally adequate diet. In this article, we report the changes that occur in free and peptide-bound amino acids (AA) of select CELSS crops (rice, wheat, and soybean) grown in the field or in CE. The nonnitrate nonprotein nitrogen fraction was extracted and then analyzed for free and peptide AA. For grain or seeds, AA levels tended to increase from field to CE conditions; however, for vegetative material, AA levels remained the same or decreased from field to CE conditions. As such compositional changes are identified, researchers will be better able to design safe and nutritious diets for astronauts while minimizing needed energy and other resources. PMID:11676459

  7. [Adsorption behavior of copper ion and methylene blue on citric acid- esterified wheat straw].

    PubMed

    Sun, Jin; Zhong, Ke-Ding; Feng, Min; Liu, Xing-Yan; Gong, Ren-Min

    2008-03-01

    A cationic adsorbent with carboxyl groups derived from citric acid- esterified wheat straw (EWS) was prepared by the method of solid phase preparation, and a batch experiment was conducted to study the adsorption behaviors of Cu (II) and methylene blue (MB) in aqueous solution on the EWS under conditions of different initial pH, adsorbent dosage, adsorbate concentration, and contact time. The results showed that the maximum adsorption of Cu (II) and MB was obtained when the initial solution pH was > or = 4.0. 96% of Cu (II) in 100 mg x L(-1) Cu solution and 99% of MB in 250 mg x L(-1) dye solution could be removed by > or = 2.0 g x L(-1) of EWS. The adsorption of Cu (II) and MB fitted the Langmuir sorption isothermal model. The maximum removal capacity (Qm) of EWS was 79.37 mg x g(-1) for Cu (II) and 312.50 mg x g(-1) for MB, and the adsorption equilibrium of Cu (II) and MB was reached within 75 min and 5 h, respectively. The adsorption processes of Cu (II) and MB could be described by pseudo-first order and pseudo-second order kinetic functions, respectively.

  8. Radiation-induced lipid peroxidation in whole grain of rye, wheat and rice: Effects on linoleic and linolenic acid

    NASA Astrophysics Data System (ADS)

    Vaca, C. E.; Harms-Ringdahl, M.

    Changes in the fatty acid composition in lipids after γ-irradation of whole grain of wheat, rye and rice were examined. The radiosensitivity of linoleic acid (18:2) and linolenic acid (18:3) was studied up to a dose of 63 kGy in seeds with different water content and after a post-irradiation storage time of 2 months. At doses in the range recommended for grain desinfestation, i.e. 0.1-1.0 kGy, no detectable degradation of 18:2 and 18:3 was found, but at the highest dose applied, 63 kGy, a degradation in the range from a few percent up to 40% was observed. Under extreme conditions, i.e. pre- and post-irradation treatment with oxygen, or when the flour prepared from the seeds was mixed with water and heated before the extraction of the lipids, a more pronounced degradation of the unsaturated fatty acids was noticed. Lipid peroxidation induced by γ-irradation was estimated using the thiobarbituric acid (TBA) method. High yields of the TBA-reactive material were formed in the three types of grain investigated corresponding to G-values in the range of 12-18. The influence on peroxidation yields of the water content of the seeds was studied in wheat. The origin of the TBA-reactive material formed in the seeds is not yet known, but could only to a minor extent be due to fatty acid peroxidation.

  9. Effects of Branched-chain Amino Acids on In vitro Ruminal Fermentation of Wheat Straw

    PubMed Central

    Zhang, Hui Ling; Chen, Yong; Xu, Xiao Li; Yang, Yu Xia

    2013-01-01

    This study investigates the effects of three branched-chain amino acids (BCAA; valine, leucine, and isoleucine) on the in vitro ruminal fermentation of wheat straw using batch cultures of mixed ruminal microorganisms. BCAA were added to the buffered ruminal fluid at a concentration of 0, 2, 4, 7, or 10 mmol/L. After 72 h of anaerobic incubation, pH, volatile fatty acids (VFA), and ammonia nitrogen (NH3-N) in the ruminal fluid were determined. Dry matter (DM) and neutral detergent fiber (NDF) degradability were calculated after determining the DM and NDF in the original material and in the residue after incubation. The addition of valine, leucine, or isoleucine increased the total VFA yields (p≤0.001). However, the total VFA yields did not increase with the increase of BCAA supplement level. Total branched-chain VFA yields linearly increased as the supplemental amount of BCAA increased (p<0.001). The molar proportions of acetate and propionate decreased, whereas that of butyrate increased with the addition of valine and isoleucine (p<0.05). Moreover, the proportions of propionate and butyrate decreased (p<0.01) with the addition of leucine. Meanwhile, the molar proportions of isobutyrate were increased and linearly decreased (p<0.001) by valine and leucine, respectively. The addition of leucine or isoleucine resulted in a linear (p<0.001) increase in the molar proportions of isovalerate. The degradability of NDF achieved the maximum when valine or isoleucine was added at 2 mmol/L. The results suggest that low concentrations of BCAA (2 mmol/L) allow more efficient regulation of ruminal fermentation in vitro, as indicated by higher VFA yield and NDF degradability. Therefore, the optimum initial dose of BCAA for in vitro ruminal fermentation is 2 mmol/L. PMID:25049818

  10. Anaphylactic augmentation by epicutaneous sensitization to acid-hydrolyzed wheat protein in a guinea pig model.

    PubMed

    Matsunaga, Kayoko; Kuroda, Yasutaka; Sakai, Shinobu; Adachi, Reiko; Teshima, Reiko; Yagami, Akiko; Itagaki, Hiroshi

    2015-12-01

    Recent reports suggest that hydrolyzed wheat protein (HWP) variants such as Glupearl® 19S (GP19S) induce immediate-type hypersensitivity via epicutaneous (EC) sensitization. The identification of strong allergens is a key step in product assessment before commercial launch. However, few reports have described the estimation of actual and potential anaphylactic sensitizing capacity. In this study we assessed the strength of both the actual and potential anaphylactic sensitizing capacity by investigating the immediate-type hypersensitivity inducing potential of HWP compared with gluten. We assessed these strengths via the EC route using an EC or intradermal (ID) sensitization method. We quantified the strength of immediate-type hypersensitivity by evaluating the titer of serum antibodies isolated from sensitized subjects using passive cutaneous anaphylaxis (PCA) reactions. We also evaluated the cross-reactivity between GP19S and gluten. GP19S and gluten applied by both the sensitization methods induced obvious IgG1-mediated PCA reactions. GP19S had stronger sensitizing potential than gluten, according to the serum titers and dye spot diameters. The difference in antibody titers between GP19S and gluten was 16-fold for the EC method versus 2-fold for the ID method. GP19S cross-reacted with gluten. Acid hydrolysis of gluten increased anaphylactic sensitizing capacity in the EC method. To our knowledge, our study is the first to quantitatively confirm that HWP and gluten can induce immediate-type hypersensitivity through an intact skin. These findings suggest that acid-HWP imposes a higher risk of EC sensitization than gluten because of the ease with which the former confers a sensitizing effect through the intact skin. PMID:26558455

  11. Effect of acid concentration and treatment time on acid-alcohol modified jackfruit seed starch properties.

    PubMed

    Dutta, Himjyoti; Paul, Sanjib Kumar; Kalita, Dipankar; Mahanta, Charu Lata

    2011-09-15

    The properties of starch extracted from jackfruit (Artocarpus heterophyllus Lam.) seeds, collected from west Assam after acid-alcohol modification by short term treatment (ST) for 15-30min with concentrated hydrochloric acid and long term treatment (LT) for 1-15days with 1M hydrochloric acid, were investigated. Granule density, freeze thaw stability, solubility and light transmittance of the treated starches increased. A maximum decrease in the degree of polymerisation occurred in ST of 30min (2607.6). Jackfruit starch had 27.1±0.04% amylose content (db), which in ST initially decreased and then increased with the severity of treatment; in LT the effect was irregular. The pasting profile and granule morphology of the treated samples were severely modified. Native starch had the A-type crystalline pattern and crystalline structure increased on treatment. FTIR spectra revealed slight changes in bond stretching and bending. Colour measurement indicated that whiteness increased on treatment. Acid modified jackfruit seed starch can have applications in the food industry.

  12. Effect of acid concentration and treatment time on acid-alcohol modified jackfruit seed starch properties.

    PubMed

    Dutta, Himjyoti; Paul, Sanjib Kumar; Kalita, Dipankar; Mahanta, Charu Lata

    2011-09-15

    The properties of starch extracted from jackfruit (Artocarpus heterophyllus Lam.) seeds, collected from west Assam after acid-alcohol modification by short term treatment (ST) for 15-30min with concentrated hydrochloric acid and long term treatment (LT) for 1-15days with 1M hydrochloric acid, were investigated. Granule density, freeze thaw stability, solubility and light transmittance of the treated starches increased. A maximum decrease in the degree of polymerisation occurred in ST of 30min (2607.6). Jackfruit starch had 27.1±0.04% amylose content (db), which in ST initially decreased and then increased with the severity of treatment; in LT the effect was irregular. The pasting profile and granule morphology of the treated samples were severely modified. Native starch had the A-type crystalline pattern and crystalline structure increased on treatment. FTIR spectra revealed slight changes in bond stretching and bending. Colour measurement indicated that whiteness increased on treatment. Acid modified jackfruit seed starch can have applications in the food industry. PMID:25212133

  13. Transgenic barley (Hordeum vulgare L.) expressing the wheat aluminium resistance gene (TaALMT1) shows enhanced phosphorus nutrition and grain production when grown on an acid soil.

    PubMed

    Delhaize, Emmanuel; Taylor, Phillip; Hocking, Peter J; Simpson, Richard J; Ryan, Peter R; Richardson, Alan E

    2009-06-01

    Barley (Hordeum vulgare L.), genetically modified with the Al(3+) resistance gene of wheat (TaALMT1), was compared with a non-transformed sibling line when grown on an acidic and highly phosphate-fixing ferrosol supplied with a range of phosphorus concentrations. In short-term pot trials (26 days), transgenic barley expressing TaALMT1 (GP-ALMT1) was more efficient than a non-transformed sibling line (GP) at taking up phosphorus on acid soil, but the genotypes did not differ when the soil was limed. Differences in phosphorus uptake efficiency on acid soil could be attributed not only to the differential effects of aluminium toxicity on root growth between the genotypes, but also to differences in phosphorus uptake per unit root length. Although GP-ALMT1 out-performed GP on acid soil, it was still not as efficient at taking up phosphorus as plants grown on limed soil. GP-ALMT1 plants grown in acid soil possessed substantially smaller rhizosheaths than those grown in limed soil, suggesting that root hairs were shorter. This is a probable reason for the lower phosphorus uptake efficiency. When grown to maturity in large pots, GP-ALMT1 plants produced more than twice the grain as GP plants grown on acid soil and 80% of the grain produced by limed controls. Expression of TaALMT1 in barley was not associated with a penalty in either total shoot or grain production in the absence of Al(3+), with both genotypes showing equivalent yields in limed soil. These findings demonstrate that an important crop species can be genetically engineered to successfully increase grain production on an acid soil.

  14. Compound-Specific δ¹⁵N and δ¹³C Analyses of Amino Acids for Potential Discrimination between Organically and Conventionally Grown Wheat.

    PubMed

    Paolini, Mauro; Ziller, Luca; Laursen, Kristian Holst; Husted, Søren; Camin, Federica

    2015-07-01

    We present a study deploying compound-specific nitrogen and carbon isotope analysis of amino acids to discriminate between organically and conventionally grown plants. We focused on grain samples of common wheat and durum wheat grown using synthetic nitrogen fertilizers, animal manures, or green manures from nitrogen-fixing legumes. The measurement of amino acid δ(15)N and δ(13)C values, after protein hydrolysis and derivatization, was carried out using gas chromatography-combustion-isotope ratio mass spectrometry (GC-C-IRMS). Our results demonstrated that δ(13)C of glutamic acid and glutamine in particular, but also the combination of δ(15)N and δ(13)C of 10 amino acids, can improve the discrimination between conventional and organic wheat compared to stable isotope bulk tissue analysis. We concluded that compound-specific stable isotope analysis of amino acids represents a novel analytical tool with the potential to support and improve the certification and control procedures in the organic sector.

  15. TaOPR2 encodes a 12-oxo-phytodienoic acid reductase involved in the biosynthesis of jasmonic acid in wheat (Triticum aestivum L.).

    PubMed

    Wang, Yukun; Yuan, Guoliang; Yuan, Shaohua; Duan, Wenjing; Wang, Peng; Bai, Jianfang; Zhang, Fengting; Gao, Shiqing; Zhang, Liping; Zhao, Changping

    2016-01-29

    The 12-oxo-phytodienoic acid reductases (OPRs) are involved in the various processes of growth and development in plants, and classified into the OPRⅠ and OPRⅡ subgroups. In higher plants, only OPRⅡ subgroup genes take part in the biosynthesis of endogenous jasmonic acid. In this study, we isolated a novel OPRⅡ subgroup gene named TaOPR2 (GeneBank accession: KM216389) from the thermo-sensitive genic male sterile (TGMS) wheat cultivar BS366. TaOPR2 was predicted to encode a protein with 390 amino acids. The encoded protein contained the typical oxidored_FMN domain, the C-terminus peroxisomal-targeting signal peptide, and conserved FMN-binding sites. TaOPR2 was mapped to wheat chromosome 7B and located on peroxisome. Protein evolution analysis revealed that TaOPR2 belongs to the OPRⅡ subgroup and shares a high degree of identity with other higher plant OPR proteins. The quantitative real-time PCR results indicated that the expression of TaOPR2 is inhibited by abscisic acid (ABA), salicylic acid (SA), gibberellic acid (GA3), low temperatures and high salinity. In contrast, the expression of TaOPR2 can be induced by wounding, drought and methyl jasmonate (MeJA). Furthermore, the transcription level of TaOPR2 increased after infection with Puccinia striiformis f. sp. tritici and Puccinia recondite f. sp. tritici. TaOPR2 has NADPH-dependent oxidoreductase activity. In addition, the constitutive expression of TaOPR2 can rescue the male sterility phenotype of Arabidopsis mutant opr3. These results suggest that TaOPR2 is involved in the biosynthesis of jasmonic acid (JA) in wheat.

  16. Production of low chlorogenic and caffeic acid containing sunflower meal protein isolate and its use in functional wheat bread making.

    PubMed

    Shchekoldina, Tatiana; Aider, Mohammed

    2014-10-01

    Sunflower meal protein isolate (SMPI) is a promising food additive in different matrices. However, the uses of SMPI are limited because of the presence of antinutritional compounds like polyphenolic substances. Chlorogenic and caffeic acids are the dominants polyphenolics in the SMPI. These substances cause significant changes of the colour of the meal, proteins and food matrices during their extraction and use as food additives. Moreover, these substances lower the nutritional value of the end product due to their interaction with some amino acids such as lysine and methionine. Thus, the removal of these substances is important to enable the use of the SMPI and meal in general in a greater extent in food applications and replacing more expensive protein sources such as soy proteins. The aim of this work was to study the production of functional bread by supplementing wheat flour with sunflower meal protein isolate (SMPI). SMPI with low content of chlorogenic and caffeic acid was usefully produced following alkaline extraction and purification with succinic acid. Purified SMPI showed well balanced amino acid profile and was characterized by high water and fat absorption capacities. It was incorporated to dough formula at 8-12 % of the total wheat flour. The results showed that production of bread supplemented with SMPI was technologically feasible. The supplemented bread had high mass volume and nutritional quality compared to the control bread. The optimal SMPI to incorporate into dough formula without significant alteration of the final bread colour was established at 10 %. This study will be helpful to find economic ways to enhance the nutritional quality of wheat bread and to improve the profitability of sunflower meal residue. PMID:25328173

  17. Phytase activity of lactic acid bacteria and their impact on the solubility of minerals from wholemeal wheat bread.

    PubMed

    Cizeikiene, Dalia; Juodeikiene, Grazina; Bartkiene, Elena; Damasius, Jonas; Paskevicius, Algimantas

    2015-01-01

    The objective of this study was to determinate phytase activity of bacteriocins producing lactic acid bacteria previously isolated from spontaneous rye sourdough. The results show that the highest extracellular phytase activity produces Pediococcus pentosaceus KTU05-8 and KTU05-9 strains with a volumetric phytase activity of 32 and 54 U/ml, respectively, under conditions similar to leavening of bread dough (pH 5.5 and 30 °C). In vitro studies in simulated gastrointestinal tract media pH provide that bioproducts prepared with P. pentosaceus strains used in wholemeal wheat bread preparation increase solubility of iron, zinc, manganese, calcium and phosphorus average 30%. Therefore, P. pentosaceus KTU05-9 and KTU05-8 strains could be recommended to use as a starter for sourdough preparation for increasing of mineral bioavailability from wholemeal wheat bread.

  18. Phytase activity of lactic acid bacteria and their impact on the solubility of minerals from wholemeal wheat bread.

    PubMed

    Cizeikiene, Dalia; Juodeikiene, Grazina; Bartkiene, Elena; Damasius, Jonas; Paskevicius, Algimantas

    2015-01-01

    The objective of this study was to determinate phytase activity of bacteriocins producing lactic acid bacteria previously isolated from spontaneous rye sourdough. The results show that the highest extracellular phytase activity produces Pediococcus pentosaceus KTU05-8 and KTU05-9 strains with a volumetric phytase activity of 32 and 54 U/ml, respectively, under conditions similar to leavening of bread dough (pH 5.5 and 30 °C). In vitro studies in simulated gastrointestinal tract media pH provide that bioproducts prepared with P. pentosaceus strains used in wholemeal wheat bread preparation increase solubility of iron, zinc, manganese, calcium and phosphorus average 30%. Therefore, P. pentosaceus KTU05-9 and KTU05-8 strains could be recommended to use as a starter for sourdough preparation for increasing of mineral bioavailability from wholemeal wheat bread. PMID:26397032

  19. Interactions of CO2, temperature and management practices: simulations with a modified version of CERES-Wheat

    NASA Technical Reports Server (NTRS)

    Tubiello, F. N.; Rosenzweig, C.; Volk, T.

    1995-01-01

    A new growth subroutine was developed for CERES-Wheat, a computer model of wheat (Triticum aestivum) growth and development. The new subroutine simulates canopy photosynthetic response to CO2 concentrations and light levels, and includes the effects of temperature on canopy light-use efficiency. Its performance was compared to the original CERES-Wheat V-2 10 in 30 different cases. Biomass and yield predictions of the two models were well correlated (correlation coefficient r > 0.95). As an application, summer growth of spring wheat was simulated at one site. Modeled crop responses to higher mean temperatures, different amounts of minimum and maximum warming, and doubled CO2 concentrations were compared to observations. The importance of irrigation and nitrogen fertilization in modulating the wheat crop climatic responses were also analyzed. Specifically, in agreement with observations, rainfed crops were found to be more sensitive to CO2 increases than irrigated ones. On the other hand, low nitrogen applications depressed the ability of the wheat crop to respond positively to CO2 increases. In general, the positive effects of high CO2 on grain yield were found to be almost completely counterbalanced by the negative effects of high temperatures. Depending on how temperature minima and maxima were increased, yield changes averaged across management practices ranged from -4% to 8%.

  20. Modifying K sup + /Na sup + discrimination in salt-stressed wheat containing individual chromosomes of a salt-tolerant lophopyrum

    SciTech Connect

    Epstein, E.; Dvorak, J.

    1990-01-01

    As outlined in the proposal for this project, the practical or applied impetus for this research is this: salinity of soils and water is inimical to the production of crops and other plants biomass, and to that extent causes a dimunition of the world's capture of solar energy. Of the two strategies of coping with this problem -- rendering soils and water less saline, and developing plants better able to cope with saline substrates -- the present project deals with the latter. The current prolonged drought in California and elsewhere in the West prompts an energetic pursuit of this option, for the availability of less water is tantamount to a general exacerbation of the salinity threat. Bread wheat, Triticum aestivum, is relatively salt-sensitive, whereas tall wheatgrass, Lophopyrum elongatum, is highly salt-tolerant, as shown in our laboratory in investigations going back to the 1960's. In the present investigation both the degree of salt tolerance and that of K{sup +}/Na{sup +} discrimination have been examined in wheat, Triticum aestivum, Chinese Spring,' the wheat x L. elongatum amphiploid, and a set of 20 disomic substitution lines. The latter would reveal which of the L. elongatum chromosomes substituted for their homoeologues in wheat contribute salt tolerance to wheat, and what congruence, if any, exists between that degree of salt tolerance and changes in K{sup +}/Na{sup +} discrimination in the target wheat.

  1. Surfactants modify the release from tablets made of hydrophobically modified poly (acrylic acid).

    PubMed

    Knöös, Patrik; Onder, Sebla; Pedersen, Lina; Piculell, Lennart; Ulvenlund, Stefan; Wahlgren, Marie

    2013-01-01

    Many novel pharmaceutically active substances are characterized by a high hydrophobicity and a low water solubility, which present challenges for their delivery as drugs. Tablets made from cross-linked hydrophobically modified poly (acrylic acid) (CLHMPAA), commercially available as Pemulen™, have previously shown promising abilities to control the release of hydrophobic model substances. This study further investigates the possibility to use CLHMPAA in tablet formulations using ibuprofen as a model substance. Furthermore, surfactants were added to the dissolution medium in order to simulate the presence of bile salts in the intestine. The release of ibuprofen is strongly affected by the presence of surfactant and/or buffer in the dissolution medium, which affect both the behaviour of CLHMPAA and the swelling of the gel layer that surrounds the disintegrating tablets. Two mechanisms of tablet disintegration were observed under shear, namely conventional dissolution of a soluble tablet matrix and erosion of swollen insoluble gel particles from the tablet. The effects of surfactant in the surrounding medium can be circumvented by addition of surfactant to the tablet. With added surfactant, tablets that may be insusceptible to the differences in bile salt level between fasted or fed states have been produced, thus addressing a central problem in controlled delivery of hydrophobic drugs. In other words CLHMPAA is a potential candidate to be used in tablet formulations for controlled release with poorly soluble drugs.

  2. Wheat gluten amino acid analysis by high-performance anion-exchange chromatography with integrated pulsed amperometric detection.

    PubMed

    Rombouts, Ine; Lagrain, Bert; Lamberts, Lieve; Celus, Inge; Brijs, Kristof; Delcour, Jan A

    2012-01-01

    This chapter describes an accurate and user-friendly method for determining amino acid composition of wheat gluten proteins and their gliadin and glutenin fractions. The method consists of hydrolysis of the peptide bonds in 6.0 M hydrochloric acid solution at 110°C for 24 h, followed by evaporation of the acid and separation of the free amino acids by high-performance anion-exchange chromatography with integrated pulsed amperometric detection. In contrast to conventional methods, the analysis requires neither pre- or postcolumn derivatization, nor a time-consuming oxidation or derivatization step prior to hydrolysis. Correction factors account for incomplete release of Val and Ile even after hydrolysis for 24 h, and for losses of Ser during evaporation. Gradient conditions including an extra eluent allow multiple sequential sample analyses without risk of Glu accumulation on the anion-exchange column which otherwise would result from high Gln levels in gluten proteins.

  3. Lactic acid bacteria community dynamics and metabolite production of rye sourdough fermentations share characteristics of wheat and spelt sourdough fermentations.

    PubMed

    Weckx, Stefan; Van der Meulen, Roel; Maes, Dominique; Scheirlinck, Ilse; Huys, Geert; Vandamme, Peter; De Vuyst, Luc

    2010-12-01

    Four spontaneous rye sourdough fermentations were performed over a period of ten days with daily back-slopping. Samples taken at all refreshment steps were used for culture-dependent and culture-independent characterization of the microbiota present. Furthermore, an extensive metabolite target analysis was performed through a combination of various chromatographic methods, including liquid chromatography coupled to mass spectrometry (LC/MS) and gas chromatography coupled to mass spectrometry (GC/MS). Spearman's rank correlation coefficients were calculated and a principal component analysis (PCA) was performed on the data obtained in this study combined with data obtained previously for wheat and spelt sourdoughs. In general, the establishment of a stable microbial ecosystem occurred through a three-phase evolution, with mainly Lactobacillus plantarum and Lactobacillus fermentum dominating the rye sourdough ecosystems. PCA revealed that ornithine and mannitol were positively correlated with rye sourdoughs, contributing to bacterial competitiveness at the onset of sourdough production. Wheat and spelt sourdoughs showed a high degree of similarity, although certain compounds (e.g. indolelactic acid) appeared to be specific for spelt sourdoughs. The production of amino acid metabolites, mainly hydroxy acids (e.g. phenyllactic acid) and alcohols (e.g. 3-methyl-1-butanol), contributed to the equilibration of the redox balance and further enhanced the competitiveness of dominant species in stable sourdoughs.

  4. Population dynamics and metabolite target analysis of lactic acid bacteria during laboratory fermentations of wheat and spelt sourdoughs.

    PubMed

    Van der Meulen, Roel; Scheirlinck, Ilse; Van Schoor, Ann; Huys, Geert; Vancanneyt, Marc; Vandamme, Peter; De Vuyst, Luc

    2007-08-01

    Four laboratory sourdough fermentations, initiated with wheat or spelt flour and without the addition of a starter culture, were prepared over a period of 10 days with daily back-slopping. Samples taken at all refreshment steps were used for determination of the present microbiota. Furthermore, an extensive metabolite target analysis of more than 100 different compounds was performed through a combination of various chromatographic methods including liquid chromatography-mass spectrometry and gas chromatography-mass spectrometry. The establishment of a stable microbial ecosystem occurred through a three-phase evolution within a week, as revealed by both microbiological and metabolite analyses. Strains of Lactobacillus plantarum, Lactobacillus fermentum, Lactobacillus rossiae, Lactobacillus brevis, and Lactobacillus paraplantarum were dominating some of the sourdough ecosystems. Although the heterofermentative L. fermentum was dominating one of the wheat sourdoughs, all other sourdoughs were dominated by a combination of obligate and facultative heterofermentative taxa. Strains of homofermentative species were not retrieved in the stable sourdough ecosystems. Concentrations of sugar and amino acid metabolites hardly changed during the last days of fermentation. Besides lactic acid, ethanol, and mannitol, the production of succinic acid, erythritol, and various amino acid metabolites, such as phenyllactic acid, hydroxyphenyllactic acid, and indolelactic acid, was shown during fermentation. Physiologically, they contributed to the equilibration of the redox balance. The biphasic approach of the present study allowed us to map some of the interactions taking place during sourdough fermentation and helped us to understand the fine-tuned metabolism of lactic acid bacteria, which allows them to dominate a food ecosystem.

  5. Em polypeptide and its messenger RNA levels are modulated by abscisic acid during embryogenesis in wheat.

    PubMed

    Williamson, J D; Quatrano, R S; Cuming, A C

    1985-10-15

    The effect of abscisic acid (ABA) on the expression of the 'early-methionine-labeled' (Em) polypeptide was examined in cultured, immature wheat (Triticum aestivum, L.) embryos and in developing embryos in planta. A complementary DNA (cDNA) library was constructed from poly(A)-rich RNA from immature embryos cultured in the presence of ABA. ABA-enhanced sequences were first identified by differential colony-blot hybridization, and then verified using RNA slot-blot analysis. Dot-blot hybridization showed that one clone, p1015, was homologous to the previously isolated Em cDNA, pWG432. Electrophoretic analysis of the hybrid-select translation product of p1015 confirmed its identity as an Em sequence. Comparison of the p1015 cDNA insert size and the Em message size, from northern blot analysis, showed that p1015 contained about 87% of the Em sequence. RNA slot-blot analysis and protein electrophoresis showed that Em message, but not Em protein, accumulated at a low, basal level in immature embryos in the absence of ABA. Neither Em message nor Em protein was seen in three-day germinated seedlings. Steady-state levels of Em message and protein increased in immature embryos in the presence of ABA, both in culture and in planta. Regulation appeared to be primarily at the level of transcription or specific message stability. Regulation may also involve specific protein stability, since synthesis of Em protein continued in immature embryos in the absence of ABA, but Em protein did not accumulate in detectable amounts. We conclude that ABA specifically modulates Em message and protein levels in immature embryos, but is probably not responsible for the embryogenic specificity of Em expression.

  6. Fermentation of xylo-oligosaccharides obtained from wheat bran and Bengal gram husk by lactic acid bacteria and bifidobacteria.

    PubMed

    Madhukumar, M S; Muralikrishna, G

    2012-12-01

    Different strains of Bifidobacteria, Lactobacilli and Pediococci spp. were evaluated for their utilization of xylo-oligosaccharides derived from Bengal gram husk and wheat bran water extractable polysaccharides. The fermentation pattern of xylo-oligosaccharides by bacteria depends on the nature of xylo-oligosaccharides i.e. degree of polymerization and arabinose to xylose ratio as well as the bacterial strain tested, which inturn are very important for designing species-specific prebiotic xylo-oligosaccharides and synbiotic preparations for incorporation in various health foods. All the bacterial strains tested readily utilized xylo-oligosaccharides derived from bengal gram husk and wheat bran as indicated by the increase in (a) turbidity of the culture broth (b) xylanase, xylosidase and arabinosidase activities (c) dry cell mass and (d) the liberation of short chain fatty acids (SCFA). Acetate was found to be the major SCFA produced as the end product of fermentation and its amount varied from 75.4 to 100 mol%. Xylo-oligosaccharides derived from wheat bran were found to have better prebiotic activity compared to the one derived from Bengal gram husk and this can be ascribed to relatively high amount of arabinose.

  7. Fermentation of xylo-oligosaccharides obtained from wheat bran and Bengal gram husk by lactic acid bacteria and bifidobacteria.

    PubMed

    Madhukumar, M S; Muralikrishna, G

    2012-12-01

    Different strains of Bifidobacteria, Lactobacilli and Pediococci spp. were evaluated for their utilization of xylo-oligosaccharides derived from Bengal gram husk and wheat bran water extractable polysaccharides. The fermentation pattern of xylo-oligosaccharides by bacteria depends on the nature of xylo-oligosaccharides i.e. degree of polymerization and arabinose to xylose ratio as well as the bacterial strain tested, which inturn are very important for designing species-specific prebiotic xylo-oligosaccharides and synbiotic preparations for incorporation in various health foods. All the bacterial strains tested readily utilized xylo-oligosaccharides derived from bengal gram husk and wheat bran as indicated by the increase in (a) turbidity of the culture broth (b) xylanase, xylosidase and arabinosidase activities (c) dry cell mass and (d) the liberation of short chain fatty acids (SCFA). Acetate was found to be the major SCFA produced as the end product of fermentation and its amount varied from 75.4 to 100 mol%. Xylo-oligosaccharides derived from wheat bran were found to have better prebiotic activity compared to the one derived from Bengal gram husk and this can be ascribed to relatively high amount of arabinose. PMID:24293694

  8. Prediction of Digestible and Metabolizable Energy Content and Standardized Ileal Amino Acid Digestibility in Wheat Shorts and Red Dog for Growing Pigs

    PubMed Central

    Huang, Q.; Piao, X. S.; Ren, P.; Li, D. F.

    2012-01-01

    Two experiments were conducted to evaluate the effects of chemical composition of wheat shorts and red dog on energy and amino acid digestibility in growing pigs and to establish prediction models to estimate their digestible (DE) and metabolizable (ME) energy content and as well as their standardized ileal digestible (SID) amino acid content. For Exp. 1, sixteen diets were fed to thirty-two growing pigs according to a completely randomized design during three successive periods. The basal diet was based on corn and soybean meal while the other fifteen diets contained 28.8% wheat shorts (N = 7) or red dog (N = 8), added at the expense of corn and soybean meal. Over the three periods, each diet was fed to six pigs with each diet being fed to two pigs during each period. The apparent total tract digestibility (ATTD) of energy in wheat shorts and red dog averaged 75.1 and 87.9%. The DE values of wheat shorts and red dog averaged 13.8 MJ/kg (range 13.1 to 15.0 MJ/kg) and 15.1 MJ/kg (range 13.3 to 16.6 MJ/kg) of dry matter, respectively. For Exp. 2, twelve growing pigs were allotted to two 6×6 Latin Square Designs with six periods. Ten of the diets were formulated based on 60% wheat shorts or red dog and the remaining two diets were nitrogen-free diets based on cornstarch and sucrose. Chromic oxide (0.3%) was used as an indigestible marker in all diets. There were no differences (p>0.05) in SID values for the amino acids in wheat shorts and red dog except for lysine and methionine. Apparent ileal digestibility (AID) and SID values for lysine in different sources of wheat shorts or red dog, which averaged 78.1 and 87.8%, showed more variation than either methionine or tryptophan. A stepwise regression was performed to establish DE, ME and amino acid digestibility prediction models. Data indicated that fiber content and amino acid concentrations were good indicators to predict energy values and amino acid digestibility, respectively. The present study confirms the large

  9. Prediction of digestible and metabolizable energy content and standardized ileal amino Acid digestibility in wheat shorts and red dog for growing pigs.

    PubMed

    Huang, Q; Piao, X S; Ren, P; Li, D F

    2012-12-01

    Two experiments were conducted to evaluate the effects of chemical composition of wheat shorts and red dog on energy and amino acid digestibility in growing pigs and to establish prediction models to estimate their digestible (DE) and metabolizable (ME) energy content and as well as their standardized ileal digestible (SID) amino acid content. For Exp. 1, sixteen diets were fed to thirty-two growing pigs according to a completely randomized design during three successive periods. The basal diet was based on corn and soybean meal while the other fifteen diets contained 28.8% wheat shorts (N = 7) or red dog (N = 8), added at the expense of corn and soybean meal. Over the three periods, each diet was fed to six pigs with each diet being fed to two pigs during each period. The apparent total tract digestibility (ATTD) of energy in wheat shorts and red dog averaged 75.1 and 87.9%. The DE values of wheat shorts and red dog averaged 13.8 MJ/kg (range 13.1 to 15.0 MJ/kg) and 15.1 MJ/kg (range 13.3 to 16.6 MJ/kg) of dry matter, respectively. For Exp. 2, twelve growing pigs were allotted to two 6×6 Latin Square Designs with six periods. Ten of the diets were formulated based on 60% wheat shorts or red dog and the remaining two diets were nitrogen-free diets based on cornstarch and sucrose. Chromic oxide (0.3%) was used as an indigestible marker in all diets. There were no differences (p>0.05) in SID values for the amino acids in wheat shorts and red dog except for lysine and methionine. Apparent ileal digestibility (AID) and SID values for lysine in different sources of wheat shorts or red dog, which averaged 78.1 and 87.8%, showed more variation than either methionine or tryptophan. A stepwise regression was performed to establish DE, ME and amino acid digestibility prediction models. Data indicated that fiber content and amino acid concentrations were good indicators to predict energy values and amino acid digestibility, respectively. The present study confirms the large

  10. Simultaneous Inhibition of Linolenic Acid Synthesis in Winter Wheat Roots and Frost Hardening by BASF 13-338, a Derivative of Pyridazinone.

    PubMed

    Willemot, C

    1977-07-01

    Treatment of 12-day-old winter wheat (Triticum aestivum) plants with BASF 13-338 {4-chloro-5 (dimethylamino)-2-phenyl-3(2H)-pyridazinone} 36 hours before frost hardening simultaneously and completely inhibits accumulation of linolenic acid in the roots during the hardening period and the acquisition of frost resistance. Increased unsaturation of fatty acids is therefore probably an important part of the mechanism of cold adaptation in winter wheat.BASF 13-338 also prevents the increase in per cent dry weight in roots and shoots during hardening and causes a decrease in root lipid phosphorus and total fatty acids.The concurrent increase in linoleic acid and decrease in linolenic acid in the treated plants, while the level of the other fatty acids is but little affected, suggest that BASF 13-338 specifically inhibits linoleic acid desaturase.

  11. Molecular Analysis of the Polymeric Glutenins with Gliadin-Like Characteristics That Were Produced by Acid Dispersion of Wheat Gluten.

    PubMed

    Murakami, Tetsuya; Nishimura, Takahisa; Kitabatake, Naofumi; Tani, Fumito

    2016-03-01

    We had earlier shown that the dispersion of wheat gluten in acetic acid solution conferred gliadin-like characteristics to the polymeric glutenins. To elucidate the molecular behavior of its polymeric glutenins, the characteristics of gluten powder prepared from dispersions with various types of acid were investigated in this study. Mixograph measurements showed that the acid-treated gluten powders, regardless of the type of acid, had dough properties markedly weakened in both resistance and elasticity properties, as though gliadin was supplemented. The polymeric glutenins extracted with 70% ethanol increased greatly in all acid-treated gluten powders. Size exclusion HPLC and SDS-PAGE indicated that the behavior of polymeric glutenins due to acid treatment was attributed to their subunit composition rich in high molecular weight glutenin subunit (HMW-GS) and not their molecular size. The gluten prepared with the addition of NaCl in acid dispersion had properties similar to those of the control gluten. The results suggest that ionic repulsion induced by acid dispersion made the polymeric glutenins rich in HMW-GS disaggregate, and therefore, act like gliadins.

  12. Co-consumption of glucose and xylose for organic acid production by Aspergillus carbonarius cultivated in wheat straw hydrolysate.

    PubMed

    Yang, Lei; Lübeck, Mette; Souroullas, Konstantinos; Lübeck, Peter S

    2016-04-01

    Aspergillus carbonarius exhibits excellent abilities to utilize a wide range of carbon sources and to produce various organic acids. In this study, wheat straw hydrolysate containing high concentrations of glucose and xylose was used for organic acid production by A. carbonarius. The results indicated that A. carbonarius efficiently co-consumed glucose and xylose and produced various types of organic acids in hydrolysate adjusted to pH 7. The inhibitor tolerance of A. carbonarius to the hydrolysate at different pH values was investigated and compared using spores and recycled mycelia. This comparison showed a slight difference in the inhibitor tolerance of the spores and the recycled mycelia based on their growth patterns. Moreover, the wild-type and a glucose oxidase deficient (Δgox) mutant were compared for their abilities to produce organic acids using the hydrolysate and a defined medium. The two strains showed a different pattern of organic acid production in the hydrolysate where the Δgox mutant produced more oxalic acid but less citric acid than the wild-type, which was different from the results obtained in the defined medium This study demonstrates the feasibility of using lignocellulosic biomass for the organic acid production by A. carbonarius.

  13. Lipid metabolism is differentially modulated by salicylic acid and heptanoyl salicylic acid during the induction of resistance in wheat against powdery mildew.

    PubMed

    Tayeh, Christine; Randoux, Béatrice; Bourdon, Natacha; Reignault, Philippe

    2013-12-15

    Heptanoyl salicylic acid (HSA) is a salicylic acid (SA) derivative obtained by esterification of 2-OH benzoic acid with heptanoic acid. In wheat, the protection levels obtained against Blumeria graminis f. sp. tritici (Bgt) increased from 50% with SA to 95% with HSA. Using molecular, biochemical and cytological approaches, we investigated here how wheat lipid metabolism is differentially activated by SA and HSA in both infectious and non-infectious conditions, and how Bgt infectious process is altered by both inducers. First, in the absence of Bgt, continuous lipoxygenase (LOX)-encoding gene expression and corresponding activity were specifically induced by HSA. Moreover, compared to SA, HSA treatment resulted in earlier up-regulations of the phospholipase C2-encoding gene expression and it specifically affected the expression of a lipid transfer protein-encoding gene. In infectious context, both HSA and SA sprayings impaired penetration events and therefore haustorium formation, leading to less frequent fungal colonies. While this alteration only slowed down the evolution of Bgt infectious process in SA-sprayed leaves, it completely impaired the establishment of successful infectious events in HSA-sprayed leaves. In addition, HSA induced continuous increases of a LOX-encoding gene expression and of the corresponding LOX activity when compared to SA-sprayed leaves. Lipid metabolism is therefore overall highly responsive to HSA spraying and could represent effective defence mechanism triggered during the induction of resistance in wheat toward Bgt. The concepts of priming and energy costs of the defences induced by SA and HSA are also discussed.

  14. Production of hydroxylated fatty acids in genetically modified plants

    DOEpatents

    Somerville, Chris; Broun, Pierre; van de Loo, Frank; Boddupalli, Sekhar S.

    2011-08-23

    This invention relates to plant fatty acyl hydroxylases. Methods to use conserved amino acid or nucleotide sequences to obtain plant fatty acyl hydroxylases are described. Also described is the use of cDNA clones encoding a plant hydroxylase to produce a family of hydroxylated fatty acids in transgenic plants. In addition, the use of genes encoding fatty acid hydroxylases or desaturases to alter the level of lipid fatty acid unsaturation in transgenic plants is described.

  15. Production of hydroxylated fatty acids in genetically modified plants

    DOEpatents

    Somerville, Chris; Broun, Pierre; van de Loo, Frank; Boddupalli, Sekhar S.

    2005-08-30

    This invention relates to plant fatty acyl hydroxylases. Methods to use conserved amino acid or nucleotide sequences to obtain plant fatty acyl hydroxylases are described. Also described is the use of cDNA clones encoding a plant hydroxylase to produce a family of hydroxylated fatty acids in transgenic plants. In addition, the use of genes encoding fatty acid hydroxylases or desaturases to alter the level of lipid fatty acid unsaturation in transgenic plants is described.

  16. Increased Rat Placental Fatty Acid, but Decreased Amino Acid and Glucose Transporters Potentially Modify Intrauterine Programming.

    PubMed

    Nüsken, Eva; Gellhaus, Alexandra; Kühnel, Elisabeth; Swoboda, Isabelle; Wohlfarth, Maria; Vohlen, Christina; Schneider, Holm; Dötsch, Jörg; Nüsken, Kai-Dietrich

    2016-07-01

    Regulation of placental nutrient transport significantly affects fetal development and may modify intrauterine growth restriction (IUGR) and fetal programming. We hypothesized that placental nutrient transporters are differentially affected both by utero-placental insufficiency and prenatal surgical stress. Pregnant rats underwent bilateral uterine artery and vein ligation (LIG), sham operation (SOP) or no operation (controls, C) on gestational day E19. Placentas were obtained by caesarean section 4 h (LIG, n=20 placentas; SOP, n=24; C, n=12), 24 h (LIG, n=28; SOP, n=20; C, n=12) and 72 h (LIG, n=20; SOP, n=20; C, n=24) after surgery. Gene and protein expression of placental nutrient transporters for fatty acids (h-FABP, CD36), amino acids (SNAT1, SNAT2) and glucose (GLUT-1, Connexin 26) were examined by qRT-PCR, western blot and immunohistochemistry. Interestingly, the mean protein expression of h-FABP was doubled in placentas of LIG and SOP animals 4, 24 (SOP significant) and 72 h (SOP significant) after surgery. CD36 protein was significantly increased in LIG after 72 h. SNAT1 and SNAT2 protein and gene expressions were significantly reduced in LIG and SOP after 24 h. Further significantly reduced proteins were GLUT-1 in LIG (4 h, 72 h) and SOP (24 h), and Connexin 26 in LIG (72 h). In conclusion, placental nutrient transporters are differentially affected both by reduced blood flow and stress, probably modifying the already disturbed intrauterine milieu and contributing to IUGR and fetal programming. Increased fatty acid transport capacity may affect energy metabolism and could be a compensatory reaction with positive effects on brain development. J. Cell. Biochem. 117: 1594-1603, 2016. © 2015 Wiley Periodicals, Inc.

  17. Effects of Modifier Type on Properties of in Situ Organo-Montmorillonite Modified Wood Flour/Poly(lactic acid) Composites.

    PubMed

    Liu, Ru; Chen, Yu; Cao, Jinzhen

    2016-01-13

    Wood flour (WF) was modified with sodium-montmorillonite (Na-MMT) and two types of surfactant modifiers, namely, didecyl dimethylammonium chloride (DDAC) and sodium dodecyl sulfonate (SDS) though a two-step process inside WF. The thus-modified WFs were characterized, and the effects of MMT type on physical, mechanical, and thermal properties of their composites with poly(lactic acid) (PLA) were investigated. The results showed: (1) either DDAC or SDS could modified Na-MMT into OMMT, and then uniformly distributed in WF cell walls; (2) OMMT improved the physical properties, most mechanical properties, and thermal properties of the composites except for the impact strength; and (3) compared with SDS, DDAC seemed to perform better in properties of composites. However, DDAC showed some negative effect on the early stage of composite thermal decomposition. PMID:26671464

  18. The oxygen isotope composition of phosphate released from phytic acid by the activity of wheat and Aspergillus niger phytase

    NASA Astrophysics Data System (ADS)

    von Sperber, C.; Tamburini, F.; Brunner, B.; Bernasconi, S. M.; Frossard, E.

    2015-07-01

    Phosphorus (P) is an essential nutrient for living organisms. Under P-limiting conditions plants and microorganisms can exude extracellular phosphatases that release inorganic phosphate (Pi) from organic phosphorus compounds (Porg). Phytic acid (myo-inositol hexakisphosphate, IP6) is an important form of Porg in many soils. The enzymatic hydrolysis of IP6 by phytase yields available Pi and less phosphorylated inositol derivates as products. The hydrolysis of organic P compounds by phosphatases leaves an isotopic imprint on the oxygen isotope composition (δ18O) of released Pi, which might be used to trace P in the environment. This study aims at determining the effect of phytase on the oxygen isotope composition of released Pi. For this purpose, enzymatic assays with histidine acid phytases from wheat and Aspergillus niger were prepared using IP6, adenosine 5'-monophosphate (AMP) and glycerophosphate (GPO4) as substrates. For a comparison to the δ18O of Pi released by other extracellular enzymes, enzymatic assays with acid phosphatases from potato and wheat germ with IP6 as a substrate were prepared. During the hydrolysis of IP6 by phytase, four of the six Pi were released, and one oxygen atom from water was incorporated into each Pi. This incorporation of oxygen from water into Pi was subject to an apparent inverse isotopic fractionation (ϵ ~ 6 to 10 ‰), which was similar to that imparted by acid phosphatase from potato during the hydrolysis of IP6 (ϵ ~ 7 ‰), where less than three Pi were released. The incorporation of oxygen from water into Pi during the hydrolysis of AMP and GPO4 by phytase yielded a normal isotopic fractionation (ϵ ~ -12 ‰), similar to values reported for acid phosphatases from potato and wheat germ. We attribute this similarity in ϵ to the same amino acid sequence motif (RHGXRXP) at the active site of these enzymes, which leads to similar reaction mechanisms. We suggest that the striking

  19. The oxygen isotope composition of phosphate released from phytic acid by the activity of wheat and Aspergillus niger phytase

    NASA Astrophysics Data System (ADS)

    Sperber, C. v.; Tamburini, F.; Brunner, B.; Bernasconi, S. M.; Frossard, E.

    2015-03-01

    Phosphorus (P) is an essential nutrient for living organisms. Under P-limiting conditions plants and microorganisms can exude extracellular phosphatases that release inorganic phosphate (Pi) from organic phosphorus compounds (Porg). Phytic acid (IP6) is an important form of Porg in many soils. The enzymatic hydrolysis of IP6 by phytase yields plant available inorganic phosphate (Pi) and less phosphorylated inositol derivates as products. The hydrolysis of organic P-compounds by phosphatases leaves an isotopic imprint on the oxygen isotope composition (δ18O) of released Pi, which might be used to trace P in the environment. This study aims at determining the effect of phytase on the oxygen isotope composition of released Pi. For this purpose, enzymatic assays with histidine acid phytases from wheat and Aspergillus niger were prepared using IP6, adenosine 5'monophosphate (AMP) and glycerophosphate (GPO4) as substrates. For a comparison to the δ18O of Pi released by other extracellular enzymes, enzymatic assays with acid phosphatases from potato and wheat germ with IP6 as substrate were prepared. During the hydrolysis of IP6 by phytase, four Pi are released, and one oxygen atom from water is incorporated into each Pi. This incorporation of oxygen from water into Pi is subject to an apparent inverse isotopic fractionation (ϵ ∼ 6 to 10‰), which is similar to that imparted by acid phosphatase from potato during the hydrolysis of IP6 (ϵ ∼ 7‰) where less than three Pi are released. The incorporation of oxygen from water into Pi during the hydrolysis of AMP and GPO4 by phytase yielded a normal isotopic fractionation (ϵ ∼ -12‰), again similar to values reported for acid phosphatases from potato and wheat germ. We attribute this similarity in ɛ to the same amino acid sequence motif (RHGXRXP) at the active site of these enzymes, which leads to similar reaction mechanisms. We suggest that the striking substrate-dependency of

  20. Wheat gluten amino acid composition analysis by high-performance anion-exchange chromatography with integrated pulsed amperometric detection.

    PubMed

    Rombouts, Ine; Lamberts, Lieve; Celus, Inge; Lagrain, Bert; Brijs, Kristof; Delcour, Jan A

    2009-07-17

    A simple accurate method for determining amino acid composition of wheat gluten proteins and their gliadin and glutenin fractions using high-performance anion-exchange chromatography with integrated pulsed amperometric detection is described. In contrast to most conventional methods, the analysis requires neither pre- or post-column derivatization, nor oxidation of the sample. It consists of hydrolysis (6.0M hydrochloric acid solution at 110 degrees C for 24h), evaporation of hydrolyzates (110 degrees C), and chromatographic separation of the liberated amino acids. Correction factors (f) accounted for incomplete cleavage of peptide bonds involving Val (f=1.07) and Ile (f=1.13) after hydrolysis for 24h and for Ser (f=1.32) losses during evaporation. Gradient conditions including an extra eluent (0.1M acetic acid solution) allowed multiple sequential sample analyses without risk of Glu contamination on the anion-exchange column. While gluten amino acid compositions by the present method were mostly comparable to those obtained by a conventional method involving oxidation, acid hydrolysis and post-column ninhydrin derivatization, the latter method underestimated Tyr, Val and Ile levels. Results for the other amino acids obtained by the different methods were linearly correlated (r>0.99, slope=1.03).

  1. Effect of age on the fatty acid composition of the Bacillus subtilis PO270 isolated from wheat rhizosphere.

    PubMed

    Zarnowski, Robert; Ellis, Richard J; Lewicka, Teresa; Pietr, Stanisław J

    2004-01-01

    The changes of the composition of growing medium and the fatty acid composition of Bacillus subtilis PO270, a bacterium isolated from the wheat rhizosphere, was evaluated during different phases of growth. During growth alkalinity reaction of medium was observed and in late stationary phase of growth the release of proteins and phenolic acids from cells was observed. Twenty six fatty acids were detected. The most prominent fatty acids found in bacterial cells were 15:0 a, 15:0 i, 17:0 alpha and 17:0 i. Depending of a phase of bacterial growth, their contents varied from 86.5 to 88.9% of total fatty acids. The remaining fatty acids identified, including regular saturated and monounsaturated as well as iso- and anteiso-branched, 2- and 3-hydroxylated, cyclopropane and odd-numbered derivatives, were present in minor amounts. We have demonstrated that the fatty acid composition of this bacterium changes greatly in different growth phases. These structural changes represent re-arrangement of membranes, which keeps the bacterial cell fit during growth and counteracts the effects of the changing environment. PMID:15790076

  2. Influence of water biscuit processing and kernel puffing on the phenolic acid content and the antioxidant activity of einkorn and bread wheat.

    PubMed

    Hidalgo, Alyssa; Yilmaz, Volkan A; Brandolini, Andrea

    2016-01-01

    The whole meal flour of wheat is rich in phenolic acids, which provide a relevant antioxidant activity to food products. Aim of this research was to assess the influence of processing on phenolic acid content and antioxidant activity of whole meal flour water biscuits and puffed kernels of einkorn and bread wheat. To this end, the evolution of syringaldehyde, ferulic, vanillic, syringic, p-coumaric, p-hydroxybenzoic, and caffeic acids was studied during manufacturing. Overall, from flour to water biscuit, the total soluble conjugated phenolic acids increased slightly in einkorn, while the insoluble bound phenolic acids decreased in all the accessions as a consequence of losses during the mixing step. In the puffed kernels, instead, the total soluble conjugated phenolic acids increased markedly, while the bound phenolics did not show any clear change, evidencing their high thermal stability. The antioxidant activity, measured by FRAP and ABTS, increased during processing and was highest under the most drastic puffing conditions. PMID:26787973

  3. Lactic acid production from lime-treated wheat straw by Bacillus coagulans: neutralization of acid by fed-batch addition of alkaline substrate

    PubMed Central

    Maas, Ronald H. W.; Bakker, Robert R.; Jansen, Mickel L. A.; Visser, Diana; de Jong, Ed; Eggink, Gerrit

    2008-01-01

    Conventional processes for lignocellulose-to-organic acid conversion requires pretreatment, enzymatic hydrolysis, and microbial fermentation. In this study, lime-treated wheat straw was hydrolyzed and fermented simultaneously to lactic acid by an enzyme preparation and Bacillus coagulans DSM 2314. Decrease in pH because of lactic acid formation was partially adjusted by automatic addition of the alkaline substrate. After 55 h of incubation, the polymeric glucan, xylan, and arabinan present in the lime-treated straw were hydrolyzed for 55%, 75%, and 80%, respectively. Lactic acid (40.7 g/l) indicated a fermentation efficiency of 81% and a chiral l(+)-lactic acid purity of 97.2%. In total, 711 g lactic acid was produced out of 2,706 g lime-treated straw, representing 43% of the overall theoretical maximum yield. Approximately half of the lactic acid produced was neutralized by fed-batch feeding of lime-treated straw, whereas the remaining half was neutralized during the batch phase with a Ca(OH)2 suspension. Of the lime added during the pretreatment of straw, 61% was used for the neutralization of lactic acid. This is the first demonstration of a process having a combined alkaline pretreatment of lignocellulosic biomass and pH control in fermentation resulting in a significant saving of lime consumption and avoiding the necessity to recycle lime. PMID:18247027

  4. Routine sample preparation and HPLC analysis for ascorbic acid (vitamin C) determination in wheat plants and Arabidopsis leaf tissues.

    PubMed

    Szalai, Gabriella; Janda, T; Pál, Magda

    2014-06-01

    Plants have developed various mechanisms to protect themselves against oxidative stress. One of the most important non-enzymatic antioxidants is ascorbic acid. There is thus a need for a rapid, sensitive method for the analysis of the reduced and oxidised forms of ascorbic acid in crop plants. In this paper a simple, economic, selective, precise and stable HPLC method is presented for the detection of ascorbate in plant tissue. The sensitivity, the short retention time and the simple isocratic elution mean that the method is suitable for the routine quantification of ascorbate in a high daily sample number. The method has been found to be better than previously reported methods, because of the use of an economical, readily available mobile phase, UV detection and the lack of complicated extraction procedures. The method has been tested on Arabidopsis plants with different ascorbate levels and on wheat plants during Cd stress.

  5. Antifungal activities of three different Lactobacillus species and their production of antifungal carboxylic acids in wheat sourdough.

    PubMed

    Axel, Claudia; Brosnan, Brid; Zannini, Emanuele; Peyer, Lorenzo C; Furey, Ambrose; Coffey, Aidan; Arendt, Elke K

    2016-02-01

    This study was undertaken to assess the antifungal performance of three different Lactobacillus species.Experiments were conducted in vitro and in situ to extend the shelf life of wheat bread. Standard sourdough analyses were performed characterising acidity and carbohydrate levels. Overall, the strains showed good inhibition in vitro against the indicator mould Fusarium culmorum TMW4.2043. Sourdough bread fermented with Lactobacillus amylovorus DSM19280 performed best in the in situ shelf life experiment. An average shelf life extension of six more mould-free days was reached when compared to the non-acidified control bread. A range of antifungal-active acids like 3-phenyllactic acid, 4-hydroxyphenyllactic acid and 2-hydroxyisocaproic acid in quantities between 0.1 and 360 mg/kg were present in the freeze-dried sourdoughs. Their concentration differed greatly amongst the species.However, a higher concentration of these compounds could not completely justify the growth inhibition of environmental moulds. In particular, although Lb. reuteri R29 produced the highest total concentration of these active compounds in the sourdough, its addition to bread did not result in a longest shelf life. Nevertheless, when the artificial compounds were spiked into a chemically acidified dough, it succeeded in a longer shelf life (+25 %) than achieved only by acidifying the dough. This provides evidence of their contribution to the antifungal activity and their synergy in concentration levels far below their single minimal inhibition concentrations under acidic conditions.

  6. Production of hydroxylated fatty acids in genetically modified plants

    DOEpatents

    Somerville, Chris; Broun, Pierre; van de Loo, Frank

    2001-01-01

    This invention relates to plant fatty acyl hydroxylases. Methods to use conserved amino acid or nucleotide sequences to obtain plant fatty acyl hydroxylases are described. Also described is the use of cDNA clones encoding a plant hydroxylase to produce a family of hydroxylated fatty acids in transgenic plants.

  7. Improvement of Fatty Acid Profile and Studio of Rheological and Technological Characteristics in Breads Supplemented with Flaxseed, Soybean, and Wheat Bran Flours

    PubMed Central

    Osuna, Mariana B.; Judis, María A.; Romero, Ana M.; Avallone, Carmen M.; Bertola, Nora C.

    2014-01-01

    Functional breads constitute an interesting alternative as vehicle of new essential fatty acids sources. The aim of this study was to improve the fatty acids (FA) profile of bakery products, producing breads with low saturated fatty acid (SFA) content and with high polyunsaturated fatty acid (PUFA) content, through partial substitution of wheat flour by other ingredients (soy flour, flax flour, and wheat bran) and to analyze the effect of this change on the technological, rheological, and sensorial characteristics of breads. Flaxseed flour (FF), soybeans flour (SF), or wheat bran (WB) was used to replace 50, 100, and 150 g kg−1 of wheat flour (WF) in breads. FF or SF produced a decrease in monounsaturated and SFA and an increase of PUFA in these breads. Furthermore, breads replaced with FF presented considerable increase in the content of n3 FA, while, SF or WB contributed to rise of linoleic and oleic FA, respectively. The substitution percentage increase of FF, SF, or WB to formulation produced changes in the colour, rheological, textural, and technological characteristics of breads. This replacement resulted in improved lipid profile, being breads with 50 g kg−1 SF, the better acceptance, baking features, and enhanced fatty acid profile. PMID:25478592

  8. High abundances of water-soluble dicarboxylic acids, ketocarboxylic acids and α-dicarbonyls in the mountaintop aerosols over the North China Plain during wheat burning season

    NASA Astrophysics Data System (ADS)

    Kawamura, K.; Tachibana, E.; Okuzawa, K.; Aggarwal, S. G.; Kanaya, Y.; Wang, Z. F.

    2013-08-01

    Aerosol (TSP) samples were collected at the summit of Mount Tai (elevation: 1534 m a.s.l., 36.25° N, 117.10° E) located in the North China Plain using a high-volume air sampler and pre-combusted quartz filters. Sampling was conducted on day/night or 3 h basis in the period from 29 May to 28 June 2006 during the field burning of wheat straw residue and the post-burning season. The filter samples were analyzed for low-molecular-weight dicarboxylic acids, ketoacids and α-dicarbonyls using capillary gas chromatography (GC) and GC-MS employing water extraction and butyl ester derivatization. Molecular distributions of dicarboxylic acids (C2-C11, 220-6070 ng m-3) were characterized by a predominance of oxalic (C2) acid (105-3920 ng m-3) followed by succinic (C4) or malonic (C3) acid. Unsaturated aliphatic diacids, including maleic (M), isomaleic (iM) and fumaric (F) acids, were also detected together with aromatic diacids (phthalic, isophthalic and terephthalic acids). ω-oxocarboxylic acids (C2-C9, 24-610 ng m-3) were detected as the second most abundant compound class with the predominance of glyoxylic acid (11-360 ng m-3), followed by α-ketoacid (pyruvic acid, 3-140 ng m-3) and α-dicarbonyls (glyoxal, 1-230 ng m-3 and methylglyoxal, 2-120 ng m-3). We found that these levels (>6000 ng m-3 for diacids) are several times higher than those reported in Chinese megacities at ground levels. The concentrations of diacids increased from late May to early June, showing a maximum on 7 June, and then significantly decreased during the period 8-11 June, when the wind direction shifted from southerly to northerly. Similar temporal trends were found for ketocarboxylic acids and α-dicarbonyls as well as total carbon (TC) and water-soluble organic carbon (WSOC). The temporal variations of water-soluble organics were interpreted by the direct emission from the field burning of agricultural wastes (wheat straw) in the North China Plain and the subsequent photochemical oxidation of

  9. Synthesis of 2-methoxy benzoquinone and 2,6-dimethoxybenzoquinone by selected lactic acid bacteria during sourdough fermentation of wheat germ

    PubMed Central

    2013-01-01

    Background In the last decade, several studies described the promising cytotoxic activity of fermented wheat germ towards cancer cell lines and during in vivo clinical trials. Recent data suggested that the antiproliferative, antimetastatic and immunological effects of this preparation are mainly attributed to quinones. This study aimed at exploiting the potential of sourdough lactic acid bacteria fermentation to release 2-methoxy benzoquinone, and 2,6-dimethoxybenzoquinone, which are naturally present in wheat germ as glycosylated and non-physiologically active form. Results Preliminarily, forty strains of lactic acid bacteria, previously isolated from wheat germ, were in vitro screened based on β-glucosidase activity. Lactobacillus plantarum LB1 and Lactobacillus rossiae LB5 were selected based on the highest enzyme activity and on technology features. These strains were used in combination to ferment wheat germ. Raw wheat germ, without bacterial inoculum, was subjected to the same incubation and used as the control. The sourdough fermented wheat germ was characterized based on microbiological, physico-chemical and biochemical features. During incubation, the release of the non-glycosylated and physiologically active 2-methoxy benzoquinone, and 2,6-dimethoxybenzoquinone was almost completed during 24 h. Compared to the control, the concentration of the above bioactive compounds increased almost 4 and 6-folds. Both raw wheat germ (control) and sourdough fermented wheat germ were ex vivo assayed for the anti-proliferative activity towards various cell lines of germ cell tumor, colon carcinoma and ovarian carcinoma. While no effect was found for the raw wheat germ, the sourdough fermented preparation markedly and variously affected the human tumor cell lines. The values of IC50 ranged from 0.105 ± 0.005 to 0.556 ± 0.071 mg/ml, with a median value of IC50 of 0.302 mg/ml. Conclusions These results are comparable to those found for other well

  10. Comparison between wheat, triticale, rye, soyabean oil and strain of laying bird on the production, and cholesterol and fatty acid contents of eggs.

    PubMed

    Shafey, T M; Dingle, J G; McDonald, M W

    1992-05-01

    1. The effects of feeding three types of cereal grain (wheat, triticale or rye) and soyabean oil (0 or 20 g/kg) over a 12-week period on the production, yolk cholesterol and yolk fatty acid concentrations of three strains of laying pullets were studied. 2. Pullets fed on wheat- or triticale-based diets had higher body weight gains, egg productions, egg weights, egg mass and lower yolk cholesterol concentrations than pullets fed on rye-based diets. However, there were no significant differences between the cereals in yolk cholesterol content. 3. There were no significant differences between the three cereals in total food consumption of pullets nor of yolk weight nor yolk concentration of palmitic, stearic and oleic acids. 4. Pullets fed on triticale-based diets had higher yolk linoleic acid concentrations and lower yolk oleic acid: linoleic acid ratios than pullets fed on rye- or wheat-based diets. 5. Soyabean oil supplementation increased egg production, egg mass, yolk linoleic concentration and yolk unsaturated to saturated fatty acid ratio, but reduced yolk oleic acid: linoleic acid ratio. 6. There were differences between strains of pullets in weight gain, food consumption, rate of lay, egg weight and yolk cholesterol, but not in yolk fatty acid concentrations. 7. It was concluded that wheat- or triticale-based diets gave good production of eggs of lower cholesterol content, that soyabean oil supplementation gave eggs with a high unsaturated to saturated fatty acid ratio and that two strains of layers produced eggs with lower yolk cholesterol concentrations than a third strain. PMID:1623420

  11. Generation of transgenic wheat (Triticum aestivum L.) accumulating heterologous endo-xylanase or ferulic acid esterase in the endosperm

    SciTech Connect

    Harholt, Jesper; Bach, Inga C; Lind-Bouquin, Solveig; Nunan, Kylie J.; Madrid, Susan M.; Brinch-Pedersen, Henrik; Holm, Preben B.; Scheller, Henrik V.

    2009-12-08

    Endo-xylanase (from Bacillus subtilis) or ferulic acid esterase (from Aspergillus niger) were expressed in wheat under the control of the endosperm specific 1DX5 glutenin promoter. Constructs both with and without the endoplasmic reticulum retention signal KDEL were used. Transgenic plants were recovered in all four cases but no qualitative differences could be observed whether KDEL was added or not. Endo-xylanase activity in transgenic grains was increased between two and three fold relative to wild type. The grains were shriveled and had a 25-33% decrease in mass. Extensive analysis of the cell walls showed a 10-15% increase in arabinose to xylose ratio, a 50% increase in the proportion of water extractable arabinoxylan, and a shift in the MW of the water extractable arabinoxylan from being mainly larger than 85 kD to being between 2 kD and 85 kD. Ferulic acid esterase expressing grains were also shriveled and the seed weight was decreased by 20-50%. No ferulic acid esterase activity could be detected in wild type grains whereas ferulic acid esterase activity was detected in transgenic lines. The grain cell walls had 15-40% increase in water unextractable arabinoxylan and a decrease in monomeric ferulic acid between 13 and 34%. In all the plants the observed changes are consistent with a plant response that serves to minimize the effect of the heterologously expressed enzymes by increasing arabinoxylan biosynthesis and cross-linking.

  12. Surfactant-enhanced spectrofluorimetric determination of total aflatoxins from wheat samples after magnetic solid-phase extraction using modified Fe3O4 nanoparticles

    NASA Astrophysics Data System (ADS)

    Manafi, Mohammad Hanif; Allahyari, Mehdi; Pourghazi, Kamyar; Amoli-Diva, Mitra; Taherimaslak, Zohreh

    2015-07-01

    The extraction and preconcentration of total aflatoxins (including aflatoxin B1, B2, G1, and G2) using magnetic nanoparticles based solid phase extraction (MSPE) followed by surfactant-enhanced spectrofluorimetric detection was proposed. Ethylene glycol bis-mercaptoacetate modified silica coated Fe3O4 nanoparticles as an efficient antibody-free adsorbent was successfully applied to extract aflatoxins from wheat samples. High surface area and strong magnetization properties of magnetic nanoparticles were utilized to achieve high enrichment factor (97), and satisfactory recoveries (92-105%) using only 100 mg of the adsorbent. Furthermore, the fast separation time (less than 10 min) avoids many time-consuming cartridge loading or column-passing procedures accompany with the conventional SPE. In determination step, signal enhancement was performed by formation of Triton X-100 micelles around the analytes in 15% (v/v) acetonitrile-water which dramatically increase the sensitivity of the method. Main factors affecting the extraction efficiency and signal enhancement of the analytes including pH of sample solution, desorption conditions, extraction time, sample volume, adsorbent amount, surfactant concentration and volume and time of micelle formation were evaluated and optimized. Under the optimum conditions, wide linear range of 0.1-50 ng mL-1 with low detection limit of 0.03 ng mL-1 were obtained. The developed method was successfully applied to the extraction and preconcentration of aflatoxins in three commercially available wheat samples and the results were compared with the official AOAC method.

  13. Surfactant-enhanced spectrofluorimetric determination of total aflatoxins from wheat samples after magnetic solid-phase extraction using modified Fe₃O₄ nanoparticles.

    PubMed

    Manafi, Mohammad Hanif; Allahyari, Mehdi; Pourghazi, Kamyar; Amoli-Diva, Mitra; Taherimaslak, Zohreh

    2015-07-01

    The extraction and preconcentration of total aflatoxins (including aflatoxin B1, B2, G1, and G2) using magnetic nanoparticles based solid phase extraction (MSPE) followed by surfactant-enhanced spectrofluorimetric detection was proposed. Ethylene glycol bis-mercaptoacetate modified silica coated Fe3O4 nanoparticles as an efficient antibody-free adsorbent was successfully applied to extract aflatoxins from wheat samples. High surface area and strong magnetization properties of magnetic nanoparticles were utilized to achieve high enrichment factor (97), and satisfactory recoveries (92-105%) using only 100mg of the adsorbent. Furthermore, the fast separation time (less than 10 min) avoids many time-consuming cartridge loading or column-passing procedures accompany with the conventional SPE. In determination step, signal enhancement was performed by formation of Triton X-100 micelles around the analytes in 15% (v/v) acetonitrile-water which dramatically increase the sensitivity of the method. Main factors affecting the extraction efficiency and signal enhancement of the analytes including pH of sample solution, desorption conditions, extraction time, sample volume, adsorbent amount, surfactant concentration and volume and time of micelle formation were evaluated and optimized. Under the optimum conditions, wide linear range of 0.1-50 ng mL(-1) with low detection limit of 0.03 ng mL(-1) were obtained. The developed method was successfully applied to the extraction and preconcentration of aflatoxins in three commercially available wheat samples and the results were compared with the official AOAC method.

  14. Effects of Abscisic Acid and Ethylene on the Gibberellic Acid-Induced Synthesis of α-Amylase by Isolated Wheat Aleurone Layers 1

    PubMed Central

    Varty, Keith; Arreguín, Barbarín L.; Gómez, Miguel T.; López, Pablo Jaime T.; Gómez, Miguel Angel L.

    1983-01-01

    Gibberellic acid-induced α-amylase synthesis in wheat aleurone layers (Triticum aestivum L. var Potam S-70) escaped from transcriptional control 30 h after addition of the hormone, as evidenced by the tissue's loss of susceptibility to cordycepin. Abscisic acid inhibited the accumulation of α-amylase activity when added to the tissue during this cordycepin-insensitive phase of enzyme induction. α-Amylase synthesis was not restored by the addition of cordycepin, indicating that the response to abscisic acid was not dependent upon the continuous synthesis of a short lived RNA. When ethylene was added simultaneously or some time after abscisic acid, the accumulation of α-amylase activity was sustained or quickly restored. The loss of susceptibility to cordycepin was completely prevented when aleurone layers were incubated with a combination of gibberellic and abscisic acids from the start of the induction period. This effect of abscisic acid was not reversed by ethylene. On the basis of these observations, it is suggested that abscisic acid inhibits both the transcription and translation of α-amylase mRNA, and that only the latter site of action is susceptible to reversal by ethylene. The rate of incorporation of [methyl-14C]choline into phospholipids was also inhibited by abscisic acid. Ethylene reversed this effect. The effects of abscisic acid and ethylene on phospholipid synthesis were not dependent upon the presence of gibberellic acid. No direct relationship was found between the control of α-amylase synthesis and membrane formation by abscisic acid and ethylene. PMID:16663284

  15. Molecular composition and size distribution of sugars, sugar-alcohols and carboxylic acids in airborne particles during a severe urban haze event caused by wheat straw burning

    NASA Astrophysics Data System (ADS)

    Wang, Gehui; Chen, Chunlei; Li, Jianjun; Zhou, Bianhong; Xie, Mingjie; Hu, Shuyuan; Kawamura, Kimitaka; Chen, Yan

    2011-05-01

    Molecular compositions and size distributions of water-soluble organic compounds (WSOC, i.e., sugars, sugar-alcohols and carboxylic acids) in particles from urban air of Nanjing, China during a severe haze event caused by field burning of wheat straw were characterized and compared with those in the summer and autumn non-haze periods. During the haze event levoglucosan (4030 ng m -3) was the most abundant compound among the measured WSOC, followed by succinic acid, malic acid, glycerol, arabitol and glucose, being different from those in the non-haze samples, in which sucrose or azelaic acid showed a second highest concentration, although levoglucosan was the highest. The measured WSOC in the haze event were 2-20 times more than those in the non-hazy days. Size distribution results showed that there was no significant change in the compound peaks in coarse mode (>2.1 μm) with respect to the haze and non-haze samples, but a large difference in the fine fraction (<2.1 μm) was found with a sharp increase during the hazy days mostly due to the increased emissions of wheat straw burning. Molecular compositions of organic compounds in the fresh smoke particles from wheat straw burning demonstrate that sharply increased concentrations of glycerol and succinic and malic acids in the fine particles during the haze event were mainly derived from the field burning of wheat straw, although the sources of glucose and related sugar-alcohols whose concentrations significantly increased in the fine haze samples are unclear. Compared to that in the fresh smoke particles of wheat straw burning an increase in relative abundance of succinic acid to levoglucosan during the haze event suggests a significant production of secondary organic aerosols during transport of the smoke plumes.

  16. High abundances of water-soluble dicarboxylic acids, ketocarboxylic acids and α-dicarbonyls in the mountain aerosols over the North China Plain during wheat burning season

    NASA Astrophysics Data System (ADS)

    Kawamura, K.; Tachibana, E.; Okuzawa, K.; Aggarwal, S. G.; Kanaya, Y.; Wang, Z. F.

    2013-02-01

    Aerosol (TSP) samples were collected at the summit of Mount Tai (elevation: 1534 m a.s.l., 36.25° N; 117.10° E) located in the North China Plain using a high-volume air sampler and pre-combusted quartz filters. Sampling was conducted on day/night or 3 h basis in the period from 29 May to 28 June 2006 during the field burning of wheat straw residue and the post-burning season. The filter samples were analyzed for low molecular weight dicarboxylic acids, ketoacids and α-dicarbonyls using capillary gas chromatography (GC) and GC-MS employing water extraction and butyl ester derivatization. Dicarboxylic acids (C2-C11, 220-6070 ng m-3) were characterized by a predominance of oxalic (C2) acid (105-3920 ng m-3) followed by succinic (C4) or malonic (C3) acid. Unsaturated aliphatic diacids, including maleic (M), isomaleic (iM) and fumaric (F) acid, were also detected together with aromatic diacids (phthalic, iso-phthalic and tere-phthalic acids). ω-Oxocarboxylic acids (C2-C9, 24-610 ng m-3) were detected as the second most abundant compound class with the predominance of glyoxylic acid (11-360 ng m-3), followed by α-ketoacid (pyruvic acid, 3-140 ng m-3) and α-dicarbonyls (glyoxal, 1-230 ng m-3 and methylglyoxal, 2-120 ng m-3). We found that these levels (> 6000 ng m-3 for diacids) are several times higher than those reported in Chinese megacities at ground levels. The concentrations of diacids increased from late May to early June showing a maximum on 7 June and then significantly decreased during 8-11 June when the wind direction shifted from northeasterly to northerly. Similar temporal trends were found for ketocarboxylic acids and α-dicarbonyls as well as total carbon (TC) and water-soluble organic carbon (WSOC). The temporal variations of water-soluble organics were interpreted by the direct emission from the field burning products of agricultural wastes (wheat straw) in the North China Plain and the subsequent photochemical oxidation of volatile and semi

  17. Exploitation of Albanian wheat cultivars: characterization of the flours and lactic acid bacteria microbiota, and selection of starters for sourdough fermentation.

    PubMed

    Nionelli, Luana; Curri, Nertila; Curiel, José Antonio; Di Cagno, Raffaella; Pontonio, Erica; Cavoski, Ivana; Gobbetti, Marco; Rizzello, Carlo Giuseppe

    2014-12-01

    Six Albanian soft and durum wheat cultivars were characterized based on chemical and technological features, showing different attitudes for bread making. Gliadin and glutenin fractions were selectively extracted from flours, and subjected to two-dimensional electrophoresis. Linja 7 and LVS flours showed the best characteristics, and abundance of high molecular weight (HMW)-glutenins. Type I sourdoughs were prepared through back slopping procedure, and the lactic acid bacteria were typed and identified. Lactobacillus plantarum and Leuconostoc mesenteroides were the predominant species. Thirty-eight representative isolates were singly used for sourdough fermentation of soft and durum wheat Albanian flours and their selection was carried out based on growth and acidification, quotient of fermentation, and proteolytic activity. Two different pools of lactic acid bacteria were designed to ferment soft or durum wheat flours. Sourdough fermentation with mixed and selected starters positively affected the quotient of fermentation, concentration of free amino acids, profile of phenolic acids, and antioxidant and phytase activities. This study provided the basis to exploit the potential of wheat Albanian flours based on an integrated approach, which considered the characterization of the flours and the processing conditions.

  18. Effect of lactic acid fermentation of lupine wholemeal on acrylamide content and quality characteristics of wheat-lupine bread.

    PubMed

    Bartkiene, Elena; Jakobsone, Ida; Juodeikiene, Grazina; Vidmantiene, Daiva; Pugajeva, Iveta; Bartkevics, Vadims

    2013-11-01

    The effect of supplementing wheat flour at a level of 15% with lupine (Lupinus angustifolius L.) wholemeal fermented by different lactic acid bacteria on acrylamide content in bread crumb as well as on bread texture and sensory characteristics was analysed. The use of fermented lupine resulted in a lower specific volume and crumb porosity of bread on an average by 14.1% and 10.5%, respectively, while untreated lupine lowered the latter parameters at a higher level (30.8% and 20.7%, respectively). The addition of lupine resulted in a higher by 43.3% acrylamide content compared to wheat bread (19.4 µg/kg dry weight (d.w.)). Results showed that acrylamide was significantly reduced using proteolytic Lactobacillus sakei and Pediococcus pentosaceus 10 strains for lupine fermentation. Although the bread supplemented with lupine spontaneous sourdough had the lowest level of acrylamide (15.6 µg/kg d.w.), it had the malodorous flavour and was unacceptable to the consumers. The lactofermentation could increase the potential use of lupine as a food ingredient while reducing acrylamide formation and enriching bread with high quality proteins. PMID:23763660

  19. Effect of lactic acid fermentation of lupine wholemeal on acrylamide content and quality characteristics of wheat-lupine bread.

    PubMed

    Bartkiene, Elena; Jakobsone, Ida; Juodeikiene, Grazina; Vidmantiene, Daiva; Pugajeva, Iveta; Bartkevics, Vadims

    2013-11-01

    The effect of supplementing wheat flour at a level of 15% with lupine (Lupinus angustifolius L.) wholemeal fermented by different lactic acid bacteria on acrylamide content in bread crumb as well as on bread texture and sensory characteristics was analysed. The use of fermented lupine resulted in a lower specific volume and crumb porosity of bread on an average by 14.1% and 10.5%, respectively, while untreated lupine lowered the latter parameters at a higher level (30.8% and 20.7%, respectively). The addition of lupine resulted in a higher by 43.3% acrylamide content compared to wheat bread (19.4 µg/kg dry weight (d.w.)). Results showed that acrylamide was significantly reduced using proteolytic Lactobacillus sakei and Pediococcus pentosaceus 10 strains for lupine fermentation. Although the bread supplemented with lupine spontaneous sourdough had the lowest level of acrylamide (15.6 µg/kg d.w.), it had the malodorous flavour and was unacceptable to the consumers. The lactofermentation could increase the potential use of lupine as a food ingredient while reducing acrylamide formation and enriching bread with high quality proteins.

  20. Chitosan and chemically modified chitosan beads for acid dyes sorption.

    PubMed

    Azlan, Kamari; Wan Saime, Wan Ngah; Lai Ken, Liew

    2009-01-01

    The capabilities of chitosan and chitosan-EGDE (ethylene glycol diglycidyl ether) beads for removing Acid Red 37 (AR 37) and Acid Blue 25 (AB 25) from aqueous solution were examined. Chitosan beads were cross-linked with EGDE to enhance its chemical resistance and mechanical strength. Experiments were performed as a function of pH, agitation period and concentration of AR 37 and AB 25. It was shown that the adsorption capacities of chitosan for both acid dyes were comparatively higher than those of chitosan-EGDE. This is mainly because cross-linking using EGDE reduces the major adsorption sites -NH3+ on chitosan. Langmuir isotherm model showed the best conformity compared to Freundlich and BET. The kinetic experimental data agreed very well to the pseudo second-order kinetic model. The desorption study revealed that after three cycles of adsorption and desorption by NaOH and HCl, both adsorbents retained their promising adsorption abilities. FT-IR analysis proved that the adsorption of acid dyes onto chitosan-based adsorbents was a physical adsorption. Results also showed that chitosan and chitosan-EGDE beads were favourable adsorbers and could be employed as low-cost alternatives for the removal of acid dyes in wastewater treatment. PMID:19634439

  1. [Adsorption of aflatoxin on montmorillonite modified by low-molecular-weight humic acids].

    PubMed

    Yao, Jia-Jia; Kang, Fu-Xing; Gao, Yan-Zheng

    2012-03-01

    The adsorption of a typical biogenic toxin aflatoxin B1 on montmorillonite modified by low-molecular-weight humic acids (M(r) < 3 500) was investigated. The montmorillonite rapidly adsorbed the aflatoxin B1 until amounting to the maximal capacity, and then the adsorbed aflatoxin B1 slowly released into solution and reached the sorption equilibrium state after 12 h. The sorption isotherm of aflatoxin B1 by montmorillonite could be well described by Langmiur model, while the sorption isotherm by humic acid-modified montmorillonite was well fitted by using the Freundlich model. The modification of the montmorillonite with humic acids obviously enhanced its adsorption capacity for aflatoxin B1, and the amounts of aflatoxin adsorbed by modified montmorillonite were obviously higher than those by montmorillonite. The sorption enhancement by humic acid modification was attributed to (1) the enlarged adsorption sites which owed to the surface collapse of crystal layers induced by organic acids, and (2) the binding of aflatoxin with the humic acid sorbed on mineral surface. In addition, the adsorption amounts of aflatoxin by montmorillonite and modified montmorillonite increased with the increase of pH values in solution, and more significant enhancement was observed for the latter than the former, which attributed to the release of humic acids from the modified montmorillonite with the high pH values in solution. This indicates that increasing the pH values resulted in the enhanced hydrophilic property and the release of the organic acids presented in modified montmorillonite, and more sorption sites were available for aflatoxin on the modified montmorillonite. Results of this work would strengthen our understanding of the behavior and fate of biological contaminants in the environment.

  2. Comparative study of electroless nickel film on different organic acids modified cuprammonium fabric (CF)

    NASA Astrophysics Data System (ADS)

    Zhao, Hang; Lu, Yinxiang

    2016-01-01

    Nickel films were grown on citric acid (CA), malic acid (MA) and oxalic acid (OA) modified cuprammonium fabric (CF) substrates via electroless nickel deposition. The nickel films were examined using scanning electron microscopy (SEM) and X-ray diffraction (XRD). Their individual deposition rate and electromagnetic interference (EMI) shielding effectiveness (SE) were also investigated to compare the properties of electroless nickel films. SEM images illustrated that the nickel film on MA modified CF substrate was smooth and uniform, and the density of nickel nuclei was much higher. Compared with that of CA modified CF, the coverage of nickel nuclei on OA and MA modified CF substrate was very limited and the nickel particles size was too big. XRD analysis showed that the nickel films deposited on the different modified CF substrates had a structure with Ni (1 1 1) preferred orientation. All the nickel coatings via different acid modification were firmly adhered to the CF substrates, as demonstrated by an ultrasonic washing test. The result of tensile test indicated that the electroless nickel plating on CF has ability to strengthen the CF substrate while causes limited effect on tensile elongation. Moreover, the nickel film deposited on MA modified CF substrate showed more predominant in EMI SE than that deposited on CA or OA modified CF.

  3. Wheat germ oil enrichment in broiler feed with α-lipoic acid to enhance the antioxidant potential and lipid stability of meat

    PubMed Central

    2013-01-01

    Background Lipid peroxidation is the cause of declining the meat quality. Natural antioxidants plays a vital role in enhancing the stability and quality of meat. The supplementation of natural antioxidants in feed decreases lipid peroxidation and improves the stability of meat. Methods The present research was conducted to determine the effect of α-lipoic acid, α-tocopherol and wheat germ oil on the status of antioxidants, quality and lipid stability of broiler meat. One day old male broilers were fed with different feeds containing antioxidants i.e. natural (wheat germ oil) and synthetic α-tocopherol and α-lipoic acid during the two experimental years. Results The feed treatments have significant variation on the body weight and feed conversion ratio (FCR) while having no influence on the feed intake. The broilers fed on wheat germ oil (natural α-tocopherol) gained maximum body weight (2451.97 g & 2466.07 g) in the experimental years 2010–11 & 2011–12, respectively. The higher total phenolic contents were found in the broilers fed on wheat germ oil plus α-lipoic acid in breast (162.73±4.8 mg Gallic acid equivalent/100 g & 162.18±4.5 mg Gallic acid equivalent/100 g) and leg (149.67±3.3 mg Gallic acid equivalent/100 g & 146.07±3.2 mg Gallic acid equivalent/100 g) meat during both experimental years. Similar trend was observed for the 2,2-diphenyl-1-picrylhydrazyl (DPPH) and ferric reducing antioxidant power assay (FRAP). The production of malondialdehydes in the breast and leg meat increased with progressive increase in the time period. The deposition of α-tocopherol (AT) and α-lipoic acid (ALA) contents were found to be higher in the broilers fed on wheat germ oil plus α-lipoic acid in breast and leg meat during the both experimental years. Conclusion In conclusion, the combination of wheat germ oil and α-lipoic acid has more beneficial for stability and the quality of the broiler meat and more work should be needed in future for the bio

  4. Secreted Fungal Effector Lipase Releases Free Fatty Acids to Inhibit Innate Immunity-Related Callose Formation during Wheat Head Infection[W][OPEN

    PubMed Central

    Blümke, Antje; Falter, Christian; Herrfurth, Cornelia; Sode, Björn; Bode, Rainer; Schäfer, Wilhelm; Feussner, Ivo; Voigt, Christian A.

    2014-01-01

    The deposition of the (1,3)-β-glucan cell wall polymer callose at sites of attempted penetration is a common plant defense response to intruding pathogens and part of the plant’s innate immunity. Infection of the Fusarium graminearum disruption mutant Δfgl1, which lacks the effector lipase FGL1, is restricted to inoculated wheat (Triticum aestivum) spikelets, whereas the wild-type strain colonized the whole wheat spike. Our studies here were aimed at analyzing the role of FGL1 in establishing full F. graminearum virulence. Confocal laser-scanning microscopy revealed that the Δfgl1 mutant strongly induced the deposition of spot-like callose patches in vascular bundles of directly inoculated spikelets, while these callose deposits were not observed in infections by the wild type. Elevated concentrations of the polyunsaturated free fatty acids (FFAs) linoleic and α-linolenic acid, which we detected in F. graminearum wild type-infected wheat spike tissue compared with Δfgl1-infected tissue, provided clear evidence for a suggested function of FGL1 in suppressing callose biosynthesis. These FFAs not only inhibited plant callose biosynthesis in vitro and in planta but also partially restored virulence to the Δfgl1 mutant when applied during infection of wheat spikelets. Additional FFA analysis confirmed that the purified effector lipase FGL1 was sufficient to release linoleic and α-linolenic acids from wheat spike tissue. We concluded that these two FFAs have a major function in the suppression of the innate immunity-related callose biosynthesis and, hence, the progress of F. graminearum wheat infection. PMID:24686113

  5. 40 CFR 721.10529 - Cobalt iron manganese oxide, carboxylic acid-modified (generic).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Cobalt iron manganese oxide... Significant New Uses for Specific Chemical Substances § 721.10529 Cobalt iron manganese oxide, carboxylic acid... substance identified generically as cobalt iron manganese oxide, carboxylic acid-modified (PMN P-12-35)...

  6. 40 CFR 721.10529 - Cobalt iron manganese oxide, carboxylic acid-modified (generic).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Cobalt iron manganese oxide... Significant New Uses for Specific Chemical Substances § 721.10529 Cobalt iron manganese oxide, carboxylic acid... substance identified generically as cobalt iron manganese oxide, carboxylic acid-modified (PMN P-12-35)...

  7. A Sialylated Glycan Microarray Reveals Novel Interactions of Modified Sialic Acids with Proteins and Viruses*

    PubMed Central

    Song, Xuezheng; Yu, Hai; Chen, Xi; Lasanajak, Yi; Tappert, Mary M.; Air, Gillian M.; Tiwari, Vinod K.; Cao, Hongzhi; Chokhawala, Harshal A.; Zheng, Haojie; Cummings, Richard D.; Smith, David F.

    2011-01-01

    Many glycan-binding proteins in animals and pathogens recognize sialic acid or its modified forms, but their molecular recognition is poorly understood. Here we describe studies on sialic acid recognition using a novel sialylated glycan microarray containing modified sialic acids presented on different glycan backbones. Glycans terminating in β-linked galactose at the non-reducing end and with an alkylamine-containing fluorophore at the reducing end were sialylated by a one-pot three-enzyme system to generate α2–3- and α2–6-linked sialyl glycans with 16 modified sialic acids. The resulting 77 sialyl glycans were purified and quantified, characterized by mass spectrometry, covalently printed on activated slides, and interrogated with a number of key sialic acid-binding proteins and viruses. Sialic acid recognition by the sialic acid-binding lectins Sambucus nigra agglutinin and Maackia amurensis lectin-I, which are routinely used for detecting α2–6- and α2–3-linked sialic acids, are affected by sialic acid modifications, and both lectins bind glycans terminating with 2-keto-3-deoxy-d-glycero-d-galactonononic acid (Kdn) and Kdn derivatives stronger than the derivatives of more common N-acetylneuraminic acid (Neu5Ac) and N-glycolylneuraminic acid (Neu5Gc). Three human parainfluenza viruses bind to glycans terminating with Neu5Ac or Neu5Gc and some of their derivatives but not to Kdn and its derivatives. Influenza A virus also does not bind glycans terminating in Kdn or Kdn derivatives. An especially novel aspect of human influenza A virus binding is its ability to equivalently recognize glycans terminated with either α2–6-linked Neu5Ac9Lt or α2–6-linked Neu5Ac. Our results demonstrate the utility of this sialylated glycan microarray to investigate the biological importance of modified sialic acids in protein-glycan interactions. PMID:21757734

  8. The role of calcium in improving photosynthesis and related physiological and biochemical attributes of spring wheat subjected to simulated acid rain.

    PubMed

    Dolatabadian, Aria; Sanavy, Seyed Ali Mohammad Modarres; Gholamhoseini, Majid; Joghan, Aydin Khodaei; Majdi, Mohammad; Kashkooli, Arman Beyraghdar

    2013-04-01

    The response of photosynthesis parameters, catalase, superoxide dismutase and peroxidase activity, malondialdehyde, proline, chlorophyll, yield and yield components to foliar application of calcium and simulated acid rain in wheat were investigated. Foliar treatment of calcium led to significant increases in the photosynthesis rate, transpiration rate, stomatal conductance, proline, chlorophyll, yield and yield components in plants subjected to acid rain. Antioxidant enzyme activity and lipid peroxidation in the wheat leaves decreased because of calcium foliar application. Calcium hindered degradation of the rubisco subunits under acid rain treatment compared with water-treated plants. Results suggest that acid rain induces the production of free radicals resulting in lipid peroxidation of the cell membrane so that significant increase in antioxidant enzyme activity was observed. In addition, photosynthetic parameters i.e. photosynthesis rate, transpiration rate and stomatal conductance were drastically suppressed by acid rain. The cellular damage caused by free radicals might be reduced or prevented by a protective metabolism including antioxidative enzymes and calcium. We report that foliar application of calcium before acid rain may ameliorate the adverse effects of acid rain in wheat plants.

  9. The role of calcium in improving photosynthesis and related physiological and biochemical attributes of spring wheat subjected to simulated acid rain.

    PubMed

    Dolatabadian, Aria; Sanavy, Seyed Ali Mohammad Modarres; Gholamhoseini, Majid; Joghan, Aydin Khodaei; Majdi, Mohammad; Kashkooli, Arman Beyraghdar

    2013-04-01

    The response of photosynthesis parameters, catalase, superoxide dismutase and peroxidase activity, malondialdehyde, proline, chlorophyll, yield and yield components to foliar application of calcium and simulated acid rain in wheat were investigated. Foliar treatment of calcium led to significant increases in the photosynthesis rate, transpiration rate, stomatal conductance, proline, chlorophyll, yield and yield components in plants subjected to acid rain. Antioxidant enzyme activity and lipid peroxidation in the wheat leaves decreased because of calcium foliar application. Calcium hindered degradation of the rubisco subunits under acid rain treatment compared with water-treated plants. Results suggest that acid rain induces the production of free radicals resulting in lipid peroxidation of the cell membrane so that significant increase in antioxidant enzyme activity was observed. In addition, photosynthetic parameters i.e. photosynthesis rate, transpiration rate and stomatal conductance were drastically suppressed by acid rain. The cellular damage caused by free radicals might be reduced or prevented by a protective metabolism including antioxidative enzymes and calcium. We report that foliar application of calcium before acid rain may ameliorate the adverse effects of acid rain in wheat plants. PMID:24431486

  10. Enhancing aptamer function and stability via in vitro selection using modified nucleic acids.

    PubMed

    Meek, Kirsten N; Rangel, Alexandra E; Heemstra, Jennifer M

    2016-08-15

    Nucleic acid aptamers have emerged as a promising alternative to antibodies for use as recognition elements in therapeutics, bioimaging, and analytical applications. A key benefit that aptamers possess relative to antibodies is their ability to be chemically synthesized. This advantage, coupled with the broad range of modified nucleotide building blocks that can be constructed using chemical synthesis, has enabled the discovery and development of modified aptamers having extraordinary affinity, specificity, and biostability. Early efforts to generate modified aptamers focused on selection of a native DNA or RNA aptamer, followed by post-selection trial-and-error testing of modifications. However, recent advances in polymerase engineering and templated nucleic acid synthesis have enabled the direct selection of aptamers having modified backbones and nucleobases. This review will discuss these technological advances and highlight the improvements in aptamer function that have been realized through in vitro selection of non-natural nucleic acids.

  11. Modified MCM-41 as a drug delivery system for acetylsalicylic acid

    NASA Astrophysics Data System (ADS)

    Vyskočilová, Eliška; Luštická, Ivana; Paterová, Iva; Machová, Libuše; Červený, Libor

    2014-12-01

    The modification of prepared MCM-41 by different groups (amino, chloro and oxo) was studied. Prepared materials were treated by acetylsalicylic acid and hybrid materials were characterized, compared from the point of view of immobilized amount of active substance. The highest amount of acetylsalicylic acid was detected using methyl-tert- butyl ether as a solvent and MCM-41 without modification after 1 h (0.35 g per 1 g of the support) or MCM modified by amino group after 5 h (0.37 g per 1 g of the support) as a support. Using amino modified MCM, the longer treatment by acetylsalicylic acid converged to the equilibrium and after 24 h the immobilized amount was 0.3 g per 1 g. A dissolution in vitro study was carried out, comparing the stability of formed interactions. The slowest dissolution was detected using non-modified MCM-41 and oxo modified material.

  12. Enhancing aptamer function and stability via in vitro selection using modified nucleic acids.

    PubMed

    Meek, Kirsten N; Rangel, Alexandra E; Heemstra, Jennifer M

    2016-08-15

    Nucleic acid aptamers have emerged as a promising alternative to antibodies for use as recognition elements in therapeutics, bioimaging, and analytical applications. A key benefit that aptamers possess relative to antibodies is their ability to be chemically synthesized. This advantage, coupled with the broad range of modified nucleotide building blocks that can be constructed using chemical synthesis, has enabled the discovery and development of modified aptamers having extraordinary affinity, specificity, and biostability. Early efforts to generate modified aptamers focused on selection of a native DNA or RNA aptamer, followed by post-selection trial-and-error testing of modifications. However, recent advances in polymerase engineering and templated nucleic acid synthesis have enabled the direct selection of aptamers having modified backbones and nucleobases. This review will discuss these technological advances and highlight the improvements in aptamer function that have been realized through in vitro selection of non-natural nucleic acids. PMID:27012179

  13. Modified pseudomonas oleovorans phaC1 nucleic acids encoding bispecific polyhydroxyalkanoate polymerase

    DOEpatents

    Srienc, Friedrich; Jackson, John K.; Somers, David A.

    2000-01-01

    A genetically engineered Pseudomonas oleovorans phaC1 polyhydroxyalkanoate (PHA) polymerase having tailored substrate specificity is provided. The modified PHA polymerase is preferably a "bispecific" PHA polymerase capable of copolymerizing a short chain length monomer and a medium chain length monomer is provided. Methods for making the modified PHA polymerase and for making nucleic acids encoding the modified PHA polymerase are also disclosed, as are methods of producing PHA using the modified PHA polymerase. The invention further includes methods to assay for altered substrate specificity.

  14. Structurally modified fatty acids - clinical potential as tracers of metabolism

    SciTech Connect

    Dudczak, R.; Schmoliner, R.; Angelberger, P.; Knapp, F.F.; Goodman, M.M.

    1985-01-01

    Recently 15-p-iodophenyl-betamethyl-pentadecanoic acid (BMPPA) was proposed for myocardial scintigraphy, as possible probe of metabolic processes other than ..beta..-oxidation. In 19 patients myocardial scintigraphy was done after i.v. BMPPA (2 to 4 mCi). Data were collected (LAO 45/sup 0//14; anterior/5) for 100 minutes in the fasted patients. From heart (H) and liver (L) organ to background (BG) ratios were calculated, and the elimination (E) behavior was analyzed from BG (V. cava region) corrected time activity curves. In 10 patients plasma and urine were examined. By CHCl/sub 3//MeOH extraction of plasma samples (90 min. pi) both in water and in organic medium soluble catabolites were found. TLC fractionation showed that those were co-migrating, compared to standards, with benzoic acid, BMPPA and triglycerides. In urine (0 to 2h pi: 4.1% dose) hippuric acid was found. It is concluded that BMPPA is a useful agent for myocardial scintigraphy. Its longer retention in the heart compared to unbranched radioiodinated fatty acids may facilitate SPECT studies. Rate of elimination and plasma analysis indicate the metabolic breakdown of BMPPA. Yet, the complexity of the supposed mechanism may impede curve interpretation in terms of specific metabolic pathways. 19 refs., 5 tabs.

  15. Hydrothermal carbonization (HTC) of wheat straw: influence of feedwater pH prepared by acetic acid and potassium hydroxide.

    PubMed

    Reza, M Toufiq; Rottler, Erwin; Herklotz, Laureen; Wirth, Benjamin

    2015-04-01

    In this study, influence of feedwater pH (2-12) was studied for hydrothermal carbonization (HTC) of wheat straw at 200 and 260°C. Acetic acid and KOH were used as acidic and basic medium, respectively. Hydrochars were characterized by elemental and fiber analyses, SEM, surface area, pore volume and size, and ATR-FTIR, while HTC process liquids were analyzed by HPLC and GC. Both hydrochar and HTC process liquid qualities vary with feedwater pH. At acidic pH, cellulose and elemental carbon increase in hydrochar, while hemicellulose and pseudo-lignin decrease. Hydrochars produced at pH 2 feedwater has 2.7 times larger surface area than that produced at pH 12. It also has the largest pore volume (1.1 × 10(-1) ml g(-1)) and pore size (20.2 nm). Organic acids were increasing, while sugars were decreasing in case of basic feedwater, however, phenolic compounds were present only at 260°C and their concentrations were increasing in basic feedwater. PMID:25710573

  16. Imprinted zeolite modified carbon paste electrode as a potentiometric sensor for uric acid

    NASA Astrophysics Data System (ADS)

    Khasanah, Miratul; Widati, Alfa Akustia; Fitri, Sarita Aulia

    2016-03-01

    Imprinted zeolite modified carbon paste electrode (carbon paste-IZ) has been developed and applied to determine uric acid by potentiometry. The imprinted zeolite (IZ) was synthesized by the mole ratio of uric acid/Si of 0.0306. The modified electrode was manufactured by mass ratio of carbon, IZ and solid paraffin was 40:25:35. The modified electrode had shown the measurement range of 10-5 M to 10-2 M with Nernst factor of 28.6 mV/decade, the detection limit of 5.86 × 10-6 M and the accuracy of 95.3 - 105.0%. Response time of the electrode for uric acid 10-5 M - 10-2 M was 25 - 44 s. The developed electrode showed the high selectivity toward uric acid in the urea matrix. Life time of the carbon paste-IZ electrode was 10 weeks.

  17. Plants having modified response to ethylene by transformation with an ETR nucleic acid

    DOEpatents

    Meyerowitz, Elliott M.; Chang, Caren; Bleecker, Anthony B.

    2001-01-01

    The invention includes transformed plants having at least one cell transformed with a modified ETR nucleic acid. Such plants have a phenotype characterized by a decrease in the response of at least one transformed plant cell to ethylene as compared to a plant not containing the transformed plant cell. Tissue and/or temporal specificity for expression of the modified ETR nucleic acid is controlled by selecting appropriate expression regulation sequences to target the location and/or time of expression of the transformed nucleic acid. The plants are made by transforming at least one plant cell with an appropriate modified ETR nucleic acid, regenerating plants from one or more of the transformed plant cells and selecting at least one plant having the desired phenotype.

  18. A genome-wide analysis of the auxin/indole-3-acetic acid gene family in hexaploid bread wheat (Triticum aestivum L.)

    PubMed Central

    Qiao, Linyi; Zhang, Xiaojun; Han, Xiao; Zhang, Lei; Li, Xin; Zhan, Haixian; Ma, Jian; Luo, Peigao; Zhang, Wenping; Cui, Lei; Li, Xiaoyan; Chang, Zhijian

    2015-01-01

    The Auxin/indole-3-acetic acid (Aux/IAA) gene family plays key roles in the primary auxin-response process and controls a number of important traits in plants. However, the characteristics of the Aux/IAA gene family in hexaploid bread wheat (Triticum aestivum L.) have long been unknown. In this study, a comprehensive identification of the Aux/IAA gene family was performed using the latest draft genome sequence of the bread wheat “Chinese Spring.” Thirty-four Aux/IAA genes were identified, 30 of which have duplicated genes on the A, B or D sub-genome, with a total of 84 Aux/IAA sequences. These predicted Aux/IAA genes were non-randomly distributed in all the wheat chromosomes except for chromosome 2D. The information of wheat Aux/IAA proteins is also described. Based on an analysis of phylogeny, expression and adaptive evolution, we prove that the Aux/IAA family in wheat has been replicated twice in the two allopolyploidization events of bread wheat, when the tandem duplication also occurred. The duplicated genes have undergone an evolutionary process of purifying selection, resulting in the high conservation of copy genes among sub-genomes and functional redundancy among several members of the TaIAA family. However, functional divergence probably existed in most TaIAA members due to the diversity of the functional domain and expression pattern. Our research provides useful information for further research into the function of Aux/IAA genes in wheat. PMID:26483801

  19. Forest die-back modified plankton recovery from acidic stress.

    PubMed

    Vrba, Jaroslav; Kopáček, Jiří; Fott, Jan; Nedbalová, Linda

    2014-03-01

    We examined long-term data on water chemistry of Lake Rachelsee (Germany) following the changes in acidic depositions in central Europe since 1980s. Despite gradual chemical recovery of Rachelsee, its biological recovery was delayed. In 1999, lake recovery was abruptly reversed by a coincident forest die-back, which resulted in elevated terrestrial export of nitrate and ionic aluminum lasting ~5 years. This re-acidification episode provided unique opportunity to study plankton recovery in the rapidly recovering lake water after the abrupt decline in nitrate leaching from the catchment. There were sudden changes both in lake water chemistry and in plankton biomass structure, such as decreased bacterial filaments, increased phytoplankton biomass, and rotifer abundance. The shift from dominance of heterotrophic to autotrophic organisms suggested their substantial release from severe phosphorus stress. Such a rapid change in plankton structure in a lake recovering from acidity has, to the best of our knowledge, not been previously documented.

  20. Modified alginate and chitosan for lactic acid bacteria immobilization.

    PubMed

    Le-Tien, Canh; Millette, Mathieu; Mateescu, Mircea-Alexandru; Lacroix, Monique

    2004-06-01

    Beads with enhanced-stability acid media, which were based on alginate and chitosan functionalized by succinylation (increasing the anionic charges able to retain protons) or by acylation (improving matrix hydrophobicity), were developed for immobilization of bacterial cells. Beads (3 mm diameter) formed by ionotropic gelation with CaCl(2) presented good mechanical characteristics. After 30 min incubation of viable free Lactobacillus rhamnosus cells in simulated gastric fluid (pH 1.5), we noticed that the level of viable bacteria was undetectable. Bacterial immobilization in native-alginate-based beads generated a viable-cell count of 22-26%, whereas, when entrapped in succinylated alginate and chitosan beads, the percentage of viable cells was of 60 and 66%, respectively. Best viability (87%) was found for bacteria immobilized in N -palmitoylaminoethyl alginate, which affords a high protective effect, probably due to long alkyl pendants that improve the beads' hydrophobicity, limiting hydration in the acidic environment.

  1. Foliar Abscisic Acid-To-Ethylene Accumulation and Response Regulate Shoot Growth Sensitivity to Mild Drought in Wheat

    PubMed Central

    Valluru, Ravi; Davies, William J.; Reynolds, Matthew P.; Dodd, Ian C.

    2016-01-01

    Although, plant hormones play an important role in adjusting growth in response to environmental perturbation, the relative contributions of abscisic acid (ABA) and ethylene remain elusive. Using six spring wheat genotypes differing for stress tolerance, we show that young seedlings of the drought-tolerant (DT) group maintained or increased shoot dry weight (SDW) while the drought-susceptible (DS) group decreased SDW in response to mild drought. Both the DT and DS groups increased endogenous ABA and ethylene concentrations under mild drought compared to control. The DT and DS groups exhibited different SDW response trends, whereby the DS group decreased while the DT group increased SDW, to increased concentrations of ABA and ethylene under mild drought, although both groups decreased ABA/ethylene ratio under mild drought albeit at different levels. We concluded that SDW of the DT and DS groups might be distinctly regulated by specific ABA:ethylene ratio. Further, a foliar-spray of low concentrations (0.1 μM) of ABA increased shoot relative growth rate (RGR) in the DS group while ACC (1-aminocyclopropane-1-carboxylic acid, ethylene precursor) spray increased RGR in both groups compared to control. Furthermore, the DT group accumulated a significantly higher galactose while a significantly lower maltose in the shoot compared to the DS group. Taken all together, these results suggest an impact of ABA, ethylene, and ABA:ethylene ratio on SDW of wheat seedlings that may partly underlie a genotypic variability of different shoot growth sensitivities to drought among crop species under field conditions. We propose that phenotyping based on hormone accumulation, response and hormonal ratio would be a viable, rapid, and an early–stage selection tool aiding genotype selection for stress tolerance. PMID:27148292

  2. Using acid insoluble ash marker ratios (diet:digesta) to predict digestibility of wheat and barley metabolizable energy and nitrogen retention in broiler chicks.

    PubMed

    Scott, T A; Hall, J W

    1998-05-01

    Routine bioassay measurements of AME or N retention of broiler diets require measurements of gross energy (GE) or N and an acid insoluble ash marker in diet, excreta, or ileal digesta. These measurements of GE and N are time-consuming and expensive in comparison to measurements of added or natural occurring levels of acid insoluble ash. Data from bioassay measurements of AME and N retention of 138 wheat and 97 barley samples (with or without enzyme) were used to develop prediction equations relying on measurements of one that uses acid insoluble ash of diet, excreta or ileal digesta and GE and N of diet only; and a second equation using only acid insoluble ash of diet, excreta, or ileal digesta. The prediction equations demonstrate that part of or all of routine bomb calorimetry measurements for GE used to determine AME of wheat- or barley-based diets could be eliminated if a prediction error of 80 kcal/kg ME or less were acceptable. The prediction of N retention as compared to AME, based in part or totally on acid insoluble ash measurements, was less accurate; the prediction errors were equal to 2.3 and 6.5% for wheat- and barley-based diets, respectively. Ongoing research to improve the determination (speed, ease, and accuracy) of acid insoluble ash could provide a useful method to assess feeding value of ingredients and commercial poultry diets. PMID:9603354

  3. Using acid insoluble ash marker ratios (diet:digesta) to predict digestibility of wheat and barley metabolizable energy and nitrogen retention in broiler chicks.

    PubMed

    Scott, T A; Hall, J W

    1998-05-01

    Routine bioassay measurements of AME or N retention of broiler diets require measurements of gross energy (GE) or N and an acid insoluble ash marker in diet, excreta, or ileal digesta. These measurements of GE and N are time-consuming and expensive in comparison to measurements of added or natural occurring levels of acid insoluble ash. Data from bioassay measurements of AME and N retention of 138 wheat and 97 barley samples (with or without enzyme) were used to develop prediction equations relying on measurements of one that uses acid insoluble ash of diet, excreta or ileal digesta and GE and N of diet only; and a second equation using only acid insoluble ash of diet, excreta, or ileal digesta. The prediction equations demonstrate that part of or all of routine bomb calorimetry measurements for GE used to determine AME of wheat- or barley-based diets could be eliminated if a prediction error of 80 kcal/kg ME or less were acceptable. The prediction of N retention as compared to AME, based in part or totally on acid insoluble ash measurements, was less accurate; the prediction errors were equal to 2.3 and 6.5% for wheat- and barley-based diets, respectively. Ongoing research to improve the determination (speed, ease, and accuracy) of acid insoluble ash could provide a useful method to assess feeding value of ingredients and commercial poultry diets.

  4. Studies on the Simultaneous Formation of Aroma-Active and Toxicologically Relevant Vinyl Aromatics from Free Phenolic Acids during Wheat Beer Brewing.

    PubMed

    Langos, Daniel; Granvogl, Michael

    2016-03-23

    During the brewing process of wheat beer, the desired aroma-active vinyl aromatics 2-methoxy-4-vinylphenol and 4-vinylphenol as well as the undesired and toxicologically relevant styrene are formed from their respective precursors, free ferulic acid, p-coumaric acid, and cinnamic acid, deriving from the malts. Analysis of eight commercial wheat beers revealed high concentrations of 2-methoxy-4-vinylphenol and 4-vinylphenol always in parallel with high concentrations of styrene or low concentrations of the odorants in parallel with low styrene concentrations, suggesting a similar pathway. To better understand the formation of these vinyl aromatics, each process step of wheat beer brewing and the use of different strains of Saccharomyces cerevisiae were evaluated. During wort boiling, only a moderate decarboxylation of free phenolic acids and formation of desired and undesired vinyl aromatics were monitored due to the thermal treatment. In contrast, this reaction mainly occurred enzymatically catalyzed during fermentation with S. cerevisiae strain W68 with normal Pof(+) activity (phenolic off-flavor) resulting in a wheat beer eliciting the typical aroma requested by consumers due to high concentrations of 2-methoxy-4-vinylphenol (1790 μg/L) and 4-vinylphenol (937 μg/L). Unfortunately, also a high concentration of undesired styrene (28.3 μg/L) was observed. Using a special S. cerevisiae strain without Pof(+) activity resulted in a significant styrene reduction (wheat beer aroma.

  5. Studies on the Simultaneous Formation of Aroma-Active and Toxicologically Relevant Vinyl Aromatics from Free Phenolic Acids during Wheat Beer Brewing.

    PubMed

    Langos, Daniel; Granvogl, Michael

    2016-03-23

    During the brewing process of wheat beer, the desired aroma-active vinyl aromatics 2-methoxy-4-vinylphenol and 4-vinylphenol as well as the undesired and toxicologically relevant styrene are formed from their respective precursors, free ferulic acid, p-coumaric acid, and cinnamic acid, deriving from the malts. Analysis of eight commercial wheat beers revealed high concentrations of 2-methoxy-4-vinylphenol and 4-vinylphenol always in parallel with high concentrations of styrene or low concentrations of the odorants in parallel with low styrene concentrations, suggesting a similar pathway. To better understand the formation of these vinyl aromatics, each process step of wheat beer brewing and the use of different strains of Saccharomyces cerevisiae were evaluated. During wort boiling, only a moderate decarboxylation of free phenolic acids and formation of desired and undesired vinyl aromatics were monitored due to the thermal treatment. In contrast, this reaction mainly occurred enzymatically catalyzed during fermentation with S. cerevisiae strain W68 with normal Pof(+) activity (phenolic off-flavor) resulting in a wheat beer eliciting the typical aroma requested by consumers due to high concentrations of 2-methoxy-4-vinylphenol (1790 μg/L) and 4-vinylphenol (937 μg/L). Unfortunately, also a high concentration of undesired styrene (28.3 μg/L) was observed. Using a special S. cerevisiae strain without Pof(+) activity resulted in a significant styrene reduction (wheat beer aroma. PMID:26800353

  6. Application of acid-modified Imperata cylindrica powder for latent fingerprint development.

    PubMed

    Low, Wei Zeng; Khoo, Bee Ee; Aziz, Zalina Binti Abdul; Low, Ling Wei; Teng, Tjoon Tow; bin Abdullah, Ahmad Fahmi Lim

    2015-09-01

    A novel powdering material that utilizes acid-modified Imperata cylindrica (IC) powder for the development of fingermarks was studied. Experiments were carried out to determine the suitability, adherence quality and sensitivity of the acid-modified IC powder. Fingermarks of different constituents (eccrine, sebaceous and natural fingermarks) on different types of surfaces were used. Acid-modified IC powder was also used to develop fingermarks of different ages as well as aged fingermarks recovered from the water. From the visual inspection, acid-modified IC powder was able to interact with different fingermark constituents and produced distinct ridge details on the examined surfaces. It was also able to develop aged fingermarks and fingermarks that were submerged in water. A statistical comparison was made against the Sirchie® Hi-Fi black powder in terms of the powders' sensitivity and quality of the developed natural fingermarks. The image quality was analyzed using MITRE's Image Quality of Fingerprint (IQF) software. From the experiments, acid-modified IC powder has the potential as a fingermark development powder, although natural fingermarks developed by Sirchie® black powder showed better quality and sensitivity based on the results of the statistical comparison. PMID:26385718

  7. Application of acid-modified Imperata cylindrica powder for latent fingerprint development.

    PubMed

    Low, Wei Zeng; Khoo, Bee Ee; Aziz, Zalina Binti Abdul; Low, Ling Wei; Teng, Tjoon Tow; bin Abdullah, Ahmad Fahmi Lim

    2015-09-01

    A novel powdering material that utilizes acid-modified Imperata cylindrica (IC) powder for the development of fingermarks was studied. Experiments were carried out to determine the suitability, adherence quality and sensitivity of the acid-modified IC powder. Fingermarks of different constituents (eccrine, sebaceous and natural fingermarks) on different types of surfaces were used. Acid-modified IC powder was also used to develop fingermarks of different ages as well as aged fingermarks recovered from the water. From the visual inspection, acid-modified IC powder was able to interact with different fingermark constituents and produced distinct ridge details on the examined surfaces. It was also able to develop aged fingermarks and fingermarks that were submerged in water. A statistical comparison was made against the Sirchie® Hi-Fi black powder in terms of the powders' sensitivity and quality of the developed natural fingermarks. The image quality was analyzed using MITRE's Image Quality of Fingerprint (IQF) software. From the experiments, acid-modified IC powder has the potential as a fingermark development powder, although natural fingermarks developed by Sirchie® black powder showed better quality and sensitivity based on the results of the statistical comparison.

  8. Determination of electroactive organic acids by anion-exchange chromatography using a copper modified electrode.

    PubMed

    Casella, I G; Gatta, M

    2001-04-01

    An ion-chromatographic method combined with electrochemical detection at a copper-based chemically modified glassy carbon electrode (Cu-GC) has been shown to provide a simple analytical approach for the determination of some common organic acids in alkaline medium. Under the optimized isocratic chromatographic conditions (i.e. 0.1 M NaOH plus 80 mM CH3COONa), organic acids such as gallic, ascorbic, gluconic, lactobionic, galacturonic and glucuronic acid could be separated in less than 20 min. Under constant potential amperometric detection (i.e. 0.55 V vs. Ag-AgCl) the Cu-GC modified electrode allowed detection limits between 2 and 5 pmol for all investigated organic acids while the linear dynamic range spanned generally over three orders of magnitude. Examples of applications included the separation and quantitation of some common organic acids in vinegar, honey and tea samples, are given.

  9. Lactic acid bacterial extract as a biogenic mineral growth modifier

    NASA Astrophysics Data System (ADS)

    Borah, Ballav M.; Singh, Atul K.; Ramesh, Aiyagari; Das, Gopal

    2009-04-01

    The formation of minerals and mechanisms by which bacteria could control their formation in natural habitats is now of current interest for material scientists to have an insight of the mechanism of in vivo mineralization, as well as to seek industrial and technological applications. Crystalline uniform structures of calcium and barium minerals formed micron-sized building blocks when synthesized in the presence of an organic matrix consisting of secreted protein extracts from three different lactic acid bacteria (LAB) viz.: Lactobacillus plantarum MTCC 1325, Lactobacillus acidophilus NRRL B4495 and Pediococcus acidilactici CFR K7. LABs are not known to form organic matrix in biological materialization processes. The influence of these bacterial extracts on the crystallization behavior was investigated in details to test the basic coordination behavior of the acidic protein. In this report, varied architecture of the mineral crystals obtained in presence of high molecular weight protein extracts of three different LAB strains has been discussed. The role of native form of high molecular weight bacterial protein extracts in the generation of nucleation centers for crystal growth was clearly established. A model for the formation of organic matrix-cation complex and the subsequent events leading to crystal growth is proposed.

  10. Influence of organic acids on rheological and bread-making characteristics of fortified wheat flour.

    PubMed

    Gupta, Sheetal; Shimray, Crassina A; Venkateswara Rao, G

    2012-06-01

    Flour was fortified with premix containing ferrous fumarate and folic acid. Organic acids such as citric acid, malic acid and tartaric acid, which are promoters of iron bioavailability, were added at three levels and their influence on rheological and bread-making characteristics was studied. Farinograph water absorption increased with fortificants, but with addition of organic acids there was a decrease. Maximum pressure was 77 mm in control, which increased to 78-88 mm with the addition of different acids to the fortified flour. Addition of organic acids to fortified flour brought about a decrease in peak viscosity, hot paste viscosity, cold paste viscosity and setback values. The L, a and b values of fortified breads were similar to that of control. Sensory analysis revealed marginal differences in the overall quality of breads prepared with fortified flour with the addition of organic acids.

  11. Compound-Specific δ¹⁵N and δ¹³C Analyses of Amino Acids for Potential Discrimination between Organically and Conventionally Grown Wheat.

    PubMed

    Paolini, Mauro; Ziller, Luca; Laursen, Kristian Holst; Husted, Søren; Camin, Federica

    2015-07-01

    We present a study deploying compound-specific nitrogen and carbon isotope analysis of amino acids to discriminate between organically and conventionally grown plants. We focused on grain samples of common wheat and durum wheat grown using synthetic nitrogen fertilizers, animal manures, or green manures from nitrogen-fixing legumes. The measurement of amino acid δ(15)N and δ(13)C values, after protein hydrolysis and derivatization, was carried out using gas chromatography-combustion-isotope ratio mass spectrometry (GC-C-IRMS). Our results demonstrated that δ(13)C of glutamic acid and glutamine in particular, but also the combination of δ(15)N and δ(13)C of 10 amino acids, can improve the discrimination between conventional and organic wheat compared to stable isotope bulk tissue analysis. We concluded that compound-specific stable isotope analysis of amino acids represents a novel analytical tool with the potential to support and improve the certification and control procedures in the organic sector. PMID:25959490

  12. Boronic acid-modified magnetic materials for antibody purification

    PubMed Central

    Dhadge, Vijaykumar L.; Hussain, Abid; Azevedo, Ana M.; Aires-Barros, Raquel; Roque, Ana C. A.

    2014-01-01

    Aminophenyl boronic acids can form reversible covalent ester interactions with cis-diol-containing molecules, serving as a selective tool for binding glycoproteins as antibody molecules that possess oligosaccharides in both the Fv and Fc regions. In this study, amino phenyl boronic acid (APBA) magnetic particles (MPs) were applied for the magnetic separation of antibody molecules. Iron oxide MPs were firstly coated with dextran to avoid non-specific binding and then with 3-glycidyloxypropyl trimethoxysilane to allow further covalent coupling of APBA (APBA_MP). When contacted with pure protein solutions of human IgG (hIgG) and bovine serum albumin (BSA), APBA_MP bound 170 ± 10 mg hIgG g−1 MP and eluted 160 ± 5 mg hIgG g−1 MP, while binding only 15 ± 5 mg BSA g−1 MP. The affinity constant for the interaction between hIgG and APBA_MP was estimated as 4.9 × 105 M−1 (Ka) with a theoretical maximum capacity of 492 mg hIgG adsorbed g−1 MP (Qmax), whereas control particles bound a negligible amount of hIgG and presented an estimated theoretical maximum capacity of 3.1 mg hIgG adsorbed g−1 MP (Qmax). APBA_MPs were also tested for antibody purification directly from CHO cell supernatants. The particles were able to bind 98% of IgG loaded and to recover 95% of pure IgG (purity greater than 98%) at extremely mild conditions. PMID:24258155

  13. Boronic acid-modified magnetic materials for antibody purification.

    PubMed

    Dhadge, Vijaykumar L; Hussain, Abid; Azevedo, Ana M; Aires-Barros, Raquel; Roque, Ana C A

    2014-02-01

    Aminophenyl boronic acids can form reversible covalent ester interactions with cis-diol-containing molecules, serving as a selective tool for binding glycoproteins as antibody molecules that possess oligosaccharides in both the Fv and Fc regions. In this study, amino phenyl boronic acid (APBA) magnetic particles (MPs) were applied for the magnetic separation of antibody molecules. Iron oxide MPs were firstly coated with dextran to avoid non-specific binding and then with 3-glycidyloxypropyl trimethoxysilane to allow further covalent coupling of APBA (APBA_MP). When contacted with pure protein solutions of human IgG (hIgG) and bovine serum albumin (BSA), APBA_MP bound 170 ± 10 mg hIgG g(-1) MP and eluted 160 ± 5 mg hIgG g(-1) MP, while binding only 15 ± 5 mg BSA g(-1) MP. The affinity constant for the interaction between hIgG and APBA_MP was estimated as 4.9 × 10(5) M(-1) (Ka) with a theoretical maximum capacity of 492 mg hIgG adsorbed g(-1) MP (Qmax), whereas control particles bound a negligible amount of hIgG and presented an estimated theoretical maximum capacity of 3.1 mg hIgG adsorbed g(-1) MP (Qmax). APBA_MPs were also tested for antibody purification directly from CHO cell supernatants. The particles were able to bind 98% of IgG loaded and to recover 95% of pure IgG (purity greater than 98%) at extremely mild conditions.

  14. Adding wheat middlings, microbial phytase, and citric acid to corn-soybean meal diets for growing pigs may replace inorganic phosphorus supplementation.

    PubMed

    Han, Y M; Roneker, K R; Pond, W G; Lei, X G

    1998-10-01

    Three experiments were conducted with 96 growing Landrace x Yorkshire x Duroc crossbreds to determine the collective effectiveness of cereal phytase from wheat middlings, microbial phytase, and citric acid in improving phytate-P bioavailability in corn-soy diets. In Exp. 1, 40 gilts (7 wk old) were fed five diets for 8 wk. Diets 1, 2, and 3 were low-P, corn-soybean meal diets (CSB) + 0, .1, or .2% inorganic P (Pi) as calcium phosphate, respectively. Diet 4 was a similar corn-soy diet that included 15% wheat middlings (461 cereal phytase U/kg). Diet 5 was the CSB + microbial phytase (1,200 U/kg; Natuphos, BASF, Mount Olive, NJ). In Exp. 2, 16 barrows (8 wk old) were fed two diets for 6 wk. Diet 1 was the same as Diet 3 of Exp. 1 (.2% Pi). Diet 2 was Diet 4 of Exp. 1 + microbial phytase (300 U/kg). In Exp. 3, 40 barrows and gilts (6 wk old) were fed four diets for 6 wk. Diets 1 and 2 were the same as those in Exp. 2. Diet 3 was Diet 2 of Exp. 2 + 1.5% citric acid. Diet 4 was similar to Diet 3 but contained 10 instead of 15% wheat middlings. In Exp. 1, pigs fed the low-P, CSB (Diet 1) had lower (P < .05) ADG, ADFI, plasma Pi concentration, bone strength, and mobility score than pigs of the other four treatments. Measurements for pigs fed the 15% wheat middlings diet were not significantly different from those of pigs fed the CSB + .1% Pi or microbial phytase. In Exp. 2, ADG (P=.06) during wk 1 to 3 and gain:feed ratio (P < .02) and plasma Pi concentration (P < .005) during all weeks favored pigs fed the CSB + .2% Pi compared with the other diet including 15% wheat middlings. In Exp. 3, identical ADG during all weeks and similar plasma Pi concentrations at wk 4 and 6 were observed between pigs fed the two citric acid diets (Diets 3 and 4) and the CSB + .2% Pi (Diet 1). Pigs fed Diet 4 (10% wheat middlings) had even higher (P < .02) gain:feed ratio during wk 1 to 3 than those fed Diet 1. It seems feasible to completely replace calcium phosphate with 10 to 15% wheat

  15. Acid-base properties of sorbents based on modified zirconium(IV) phosphates

    SciTech Connect

    Bekrenev, A.V.; Pyartman, A.K.

    1995-11-01

    Modifying and doping syntheses are widely used to improve the reproducibility of ion-exchange properties and to increase the capacity of inorganic ion exchangers. Numerous examples of doping zirconium phosphate ion exchangers with cationic or anionic additives are known. The aim of this work was to investigate the acid-base properties of zirconium phosphates modified with anionic additives (phthalate and sulfosalicylate ions) in comparison with unmodified samples.

  16. Purification and subunit analysis of wheat-germ ribonucleic acid polymerase II

    PubMed Central

    Jendrisak, Jerome J.; Becker, Wayne M.

    1974-01-01

    A procedure is described for the purification of the α-amanitin-sensitive DNA-dependent RNA polymerase [EC 2.7.7.6] from wheat germ. Solubilization of the enzyme activity was achieved by sonication of a crude extract in a high-salt buffer. Purification involved precipitation with protamine sulphate and (NH4)2SO4, chromatography on DEAE-cellulose and phosphocellulose, and sucrose gradient centrifugation. Under denaturing conditions the enzyme dissociated into five polypeptides with molecular weights and molar ratios of 220000 (0.9), 170000 (0.1), 140000 (1.0), 45000 (0.2), and 40000 (0.4). Approx. 1mg of purified RNA polymerase was obtained as a routine from 100g of starting material. ImagesPLATE 1PLATE 2 PMID:4853970

  17. Surfactant-enhanced spectrofluorimetric determination of total aflatoxins from wheat samples after magnetic solid-phase extraction using modified Fe₃O₄ nanoparticles.

    PubMed

    Manafi, Mohammad Hanif; Allahyari, Mehdi; Pourghazi, Kamyar; Amoli-Diva, Mitra; Taherimaslak, Zohreh

    2015-07-01

    The extraction and preconcentration of total aflatoxins (including aflatoxin B1, B2, G1, and G2) using magnetic nanoparticles based solid phase extraction (MSPE) followed by surfactant-enhanced spectrofluorimetric detection was proposed. Ethylene glycol bis-mercaptoacetate modified silica coated Fe3O4 nanoparticles as an efficient antibody-free adsorbent was successfully applied to extract aflatoxins from wheat samples. High surface area and strong magnetization properties of magnetic nanoparticles were utilized to achieve high enrichment factor (97), and satisfactory recoveries (92-105%) using only 100mg of the adsorbent. Furthermore, the fast separation time (less than 10 min) avoids many time-consuming cartridge loading or column-passing procedures accompany with the conventional SPE. In determination step, signal enhancement was performed by formation of Triton X-100 micelles around the analytes in 15% (v/v) acetonitrile-water which dramatically increase the sensitivity of the method. Main factors affecting the extraction efficiency and signal enhancement of the analytes including pH of sample solution, desorption conditions, extraction time, sample volume, adsorbent amount, surfactant concentration and volume and time of micelle formation were evaluated and optimized. Under the optimum conditions, wide linear range of 0.1-50 ng mL(-1) with low detection limit of 0.03 ng mL(-1) were obtained. The developed method was successfully applied to the extraction and preconcentration of aflatoxins in three commercially available wheat samples and the results were compared with the official AOAC method. PMID:25804513

  18. Alleviation of Drought Stress by Hydrogen Sulfide Is Partially Related to the Abscisic Acid Signaling Pathway in Wheat

    PubMed Central

    Wang, Chenyang; Qin, Haixia; Han, Qiaoxia; Hou, Junfeng; Lu, Hongfang; Xie, Yingxin; Guo, Tiancai

    2016-01-01

    Little information is available describing the effects of exogenous H2S on the ABA pathway in the acquisition of drought tolerance in wheat. In this study, we investigated the physiological parameters, the transcription levels of several genes involved in the abscisic acid (ABA) metabolism pathway, and the ABA and H2S contents in wheat leaves and roots under drought stress in response to exogenous NaHS treatment. The results showed that pretreatment with NaHS significantly increased plant height and the leaf relative water content of seedlings under drought stress. Compared with drought stress treatment alone, H2S application increased antioxidant enzyme activities and reduced MDA and H2O2 contents in both leaves and roots. NaHS pretreatment increased the expression levels of ABA biosynthesis and ABA reactivation genes in leaves; whereas the expression levels of ABA biosynthesis and ABA catabolism genes were up-regulated in roots. These results indicated that ABA participates in drought tolerance induced by exogenous H2S, and that the responses in leaves and roots are different. The transcription levels of genes encoding ABA receptors were up-regulated in response to NaHS pretreatment under drought conditions in both leaves and roots. Correspondingly, the H2S contents in leaves and roots were increased by NaHS pretreatment, while the ABA contents of leaves and roots decreased. This implied that there is complex crosstalk between these two signal molecules, and that the alleviation of drought stress by H2S, at least in part, involves the ABA signaling pathway. PMID:27649534

  19. Alleviation of Drought Stress by Hydrogen Sulfide Is Partially Related to the Abscisic Acid Signaling Pathway in Wheat.

    PubMed

    Ma, Dongyun; Ding, Huina; Wang, Chenyang; Qin, Haixia; Han, Qiaoxia; Hou, Junfeng; Lu, Hongfang; Xie, Yingxin; Guo, Tiancai

    2016-01-01

    Little information is available describing the effects of exogenous H2S on the ABA pathway in the acquisition of drought tolerance in wheat. In this study, we investigated the physiological parameters, the transcription levels of several genes involved in the abscisic acid (ABA) metabolism pathway, and the ABA and H2S contents in wheat leaves and roots under drought stress in response to exogenous NaHS treatment. The results showed that pretreatment with NaHS significantly increased plant height and the leaf relative water content of seedlings under drought stress. Compared with drought stress treatment alone, H2S application increased antioxidant enzyme activities and reduced MDA and H2O2 contents in both leaves and roots. NaHS pretreatment increased the expression levels of ABA biosynthesis and ABA reactivation genes in leaves; whereas the expression levels of ABA biosynthesis and ABA catabolism genes were up-regulated in roots. These results indicated that ABA participates in drought tolerance induced by exogenous H2S, and that the responses in leaves and roots are different. The transcription levels of genes encoding ABA receptors were up-regulated in response to NaHS pretreatment under drought conditions in both leaves and roots. Correspondingly, the H2S contents in leaves and roots were increased by NaHS pretreatment, while the ABA contents of leaves and roots decreased. This implied that there is complex crosstalk between these two signal molecules, and that the alleviation of drought stress by H2S, at least in part, involves the ABA signaling pathway. PMID:27649534

  20. Cox-2 inhibitory effects of naturally occurring and modified fatty acids.

    PubMed

    Ringbom, T; Huss, U; Stenholm, A; Flock, S; Skattebøl, L; Perera, P; Bohlin, L

    2001-06-01

    In the search for new cyclooxygenase-2 (COX-2) selective inhibitors, the inhibitory effects of naturally occurring fatty acids and some of their structural derivatives on COX-2-catalyzed prostaglandin biosynthesis were investigated. Among these fatty acids, linoleic acid (LA), alpha-linolenic acid (alpha-LNA), myristic acid, and palmitic acid were isolated from a CH(2)Cl(2) extract of the plant Plantago major by bioassay-guided fractionation. Inhibitory effects of other natural, structurally related fatty acids were also investigated: stearic acid, oleic acid, pentadecanoic acid, eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA). Further, the inhibitory effects of these compounds on COX-2- and COX-1-catalyzed prostaglandin biosynthesis was compared with the inhibition of some synthesized analogues of EPA and DHA with ether or thioether functions. The most potent COX-2-catalyzed prostaglandin biosynthesis inhibitor was all-(Z)-5-thia-8,11,14,17-eicosatetraenoic acid (2), followed by EPA, DHA, alpha-LNA, LA, (7E,11Z,14Z,17Z)-5-thiaeicosa-7,11,14,17-tetraenoic acid, all-(Z)-3-thia-6,9,12,15-octadecatetraenoic acid, and (5E,9Z,12Z,15Z,18Z)-3-oxaheneicosa-5,9,12,15,18-pentaenoic acid, with IC(50) values ranging from 3.9 to180 microM. The modified compound 2 and alpha-LNA were most selective toward COX-2, with COX-2/COX-1 ratios of 0.2 and 0.1, respectively. This study shows that several of the natural fatty acids as well as all of the semisynthetic thioether-containing fatty acids inhibited COX-2-catalyzed prostaglandin biosynthesis, where alpha-LNA and compound 2 showed selectivity toward COX-2. PMID:11421736

  1. Complete amino acid sequence and structure characterization of the taste-modifying protein, miraculin.

    PubMed

    Theerasilp, S; Hitotsuya, H; Nakajo, S; Nakaya, K; Nakamura, Y; Kurihara, Y

    1989-04-25

    The taste-modifying protein, miraculin, has the unusual property of modifying sour taste into sweet taste. The complete amino acid sequence of miraculin purified from miracle fruits by a newly developed method (Theerasilp, S., and Kurihara, Y. (1988) J. Biol. Chem. 263, 11536-11539) was determined by an automatic Edman degradation method. Miraculin was a single polypeptide with 191 amino acid residues. The calculated molecular weight based on the amino acid sequence and the carbohydrate content (13.9%) was 24,600. Asn-42 and Asn-186 were linked N-glycosidically to carbohydrate chains. High homology was found between the amino acid sequences of miraculin and soybean trypsin inhibitor. PMID:2708331

  2. Differential expression of structural genes for the late phase of phytic acid biosynthesis in developing seeds of wheat (Triticum aestivum L.).

    PubMed

    Bhati, Kaushal Kumar; Aggarwal, Sipla; Sharma, Shivani; Mantri, Shrikant; Singh, Sudhir P; Bhalla, Sherry; Kaur, Jagdeep; Tiwari, Siddharth; Roy, Joy K; Tuli, Rakesh; Pandey, Ajay K

    2014-07-01

    In cereals, phytic acid (PA) or inositol hexakisphosphate (IP6) is a well-known phosphate storage compound as well as major chelator of important micronutrients (iron, zinc, calcium, etc.). Genes involved in the late phases of PA biosynthesis pathway are known in crops like maize, soybeans and barley but none have been reported from wheat. Our in silico analysis identified six wheat genes that might be involved in the biosynthesis of inositol phosphates. Four of the genes were inositol tetraphosphate kinases (TaITPK1, TaITPK2, TaITPK3, and TaITPK4), and the other two genes encode for inositol triphosphate kinase (TaIPK2) and inositol pentakisphosphate kinase (TaIPK1). Additionally, we identified a homolog of Zmlpa-1, an ABCC subclass multidrug resistance-associated transporter protein (TaMRP3) that is putatively involved in PA transport. Analyses of the mRNA expression levels of these seven genes showed that they are differentially expressed during seed development, and that some are preferentially expressed in aleurone tissue. These results suggest selective roles during PA biosynthesis, and that both lipid-independent and -dependent pathways are active in developing wheat grains. TaIPK1 and TaMRP3 were able to complement the yeast ScΔipk1 and ScΔycf1 mutants, respectively, providing evidence that the wheat genes have the expected biochemical functions. This is the first comprehensive study of the wheat genes involved in the late phase of PA biosynthesis. Knowledge generated from these studies could be utilized to develop strategies for generating low phyate wheat.

  3. Transcriptome Analysis of H2O2-Treated Wheat Seedlings Reveals a H2O2-Responsive Fatty Acid Desaturase Gene Participating in Powdery Mildew Resistance

    PubMed Central

    Tang, Lichuan; Zhao, Guangyao; Zhu, Mingzhu; Chu, Jinfang; Sun, Xiaohong; Wei, Bo; Zhang, Xiangqi; Jia, Jizeng; Mao, Long

    2011-01-01

    Hydrogen peroxide (H2O2) plays important roles in plant biotic and abiotic stress responses. However, the effect of H2O2 stress on the bread wheat transcriptome is still lacking. To investigate the cellular and metabolic responses triggered by H2O2, we performed an mRNA tag analysis of wheat seedlings under 10 mM H2O2 treatment for 6 hour in one powdery mildew (PM) resistant (PmA) and two susceptible (Cha and Han) lines. In total, 6,156, 6,875 and 3,276 transcripts were found to be differentially expressed in PmA, Han and Cha respectively. Among them, 260 genes exhibited consistent expression patterns in all three wheat lines and may represent a subset of basal H2O2 responsive genes that were associated with cell defense, signal transduction, photosynthesis, carbohydrate metabolism, lipid metabolism, redox homeostasis, and transport. Among genes specific to PmA, ‘transport’ activity was significantly enriched in Gene Ontology analysis. MapMan classification showed that, while both up- and down- regulations were observed for auxin, abscisic acid, and brassinolides signaling genes, the jasmonic acid and ethylene signaling pathway genes were all up-regulated, suggesting H2O2-enhanced JA/Et functions in PmA. To further study whether any of these genes were involved in wheat PM response, 19 H2O2-responsive putative defense related genes were assayed in wheat seedlings infected with Blumeria graminis f. sp. tritici (Bgt). Eight of these genes were found to be co-regulated by H2O2 and Bgt, among which a fatty acid desaturase gene TaFAD was then confirmed by virus induced gene silencing (VIGS) to be required for the PM resistance. Together, our data presents the first global picture of the wheat transcriptome under H2O2 stress and uncovers potential links between H2O2 and Bgt responses, hence providing important candidate genes for the PM resistance in wheat. PMID:22174904

  4. Effect of particle size reduction, hydrothermal and fermentation treatments on phytic acid content and some physicochemical properties of wheat bran.

    PubMed

    Majzoobi, Mahsa; Pashangeh, Safoora; Farahnaky, Asgar; Eskandari, Mohammad Hadi; Jamalian, Jalal

    2014-10-01

    With the aim of reducing phytic acid content of wheat bran, particle size reduction (from 1,200 to 90 μm), hydrothermal (wet steeping in acetate buffer at pH 4.8 at 55 °C for 60 min) and fermentation (using bakery yeast for 8 h at 30 °C) and combination of these treatments with particle size reduction were applied and their effects on some properties of the bran were studied. Phytic acid content decreased from 50.1 to 21.6, 32.8 and 43.9 mg/g after particle size reduction, hydrothermal and fermentation, respectively. Particle size reduction along with these treatments further reduced phytic acid content up to 76.4 % and 57.3 %, respectively. Hydrothermal and fermentation decreased, while particle size reduction alone or in combination increased bran lightness. With reducing particle size, total, soluble and insoluble fiber content decreased from 69.7 to 32.1 %, 12.2 to 7.9 % and 57.4 to 24.3 %, respectively. The highest total (74.4 %) and soluble (21.4 %) and the lowest insoluble fiber (52.1 %) content were determined for the hydrothermaled bran. Particle size reduction decreased swelling power, water solubility and water holding capacity. Swelling power and water holding capacity of the hydrothermaled and fermented brans were lower, while water solubility was higher than the control. The amount of Fe(+2), Zn(+2) and Ca(+2) decreased with reducing particle size. Fermentation had no effect on Fe(+2)and Zn(+2) but slightly reduced Ca(+2). The hydrothermal treatment slightly decreased these elements. Amongst all, hydrothermal treatment along with particle size reduction resulted in the lowest phytic acid and highest fiber content. PMID:25328222

  5. Chemical composition, silage fermentation characteristics, and in vitro ruminal fermentation parameters of potato-wheat straw silage treated with molasses and lactic acid bacteria and corn silage.

    PubMed

    Babaeinasab, Y; Rouzbehan, Y; Fazaeli, H; Rezaei, J

    2015-09-01

    The aim of this study was to determine the effect of molasses and lactic acid bacteria (LAB) on the chemical composition, silage fermentation characteristics, and in vitro ruminal fermentation parameters of an ensiled potato-wheat straw mixture in a completely randomized design with 4 replicates. Wheat straw was harvested at full maturity and potato tuber when the leaves turned yellowish. The potato-wheat straw (57:43 ratio, DM basis) mixture was treated with molasses, LAB, or a combination. Lalsil Fresh LB (Lallemand, France; containing NCIMB 40788) or Lalsil MS01 (Lallemand, France; containing MA18/5U and MA126/4U) were each applied at a rate of 3 × 10 cfu/g of fresh material. Treatments were mixed potato-wheat straw silage (PWSS) without additive, PWSS inoculated with Lalsil Fresh LB, PWSS inoculated with Lalsil MS01, PWSS + 5% molasses, PWSS inoculated with Lalsil Fresh LB + 5% molasses, PWSS inoculated with Lalsil MS01 + 5% molasses, and corn silage (CS). The compaction densities of PWSS treatments and CS were approximately 850 and 980 kg wet matter/m, respectively. After anaerobic storage for 90 d, chemical composition, silage fermentation characteristics, in vitro gas production (GP), estimated OM disappearance (OMD), ammonia-N, VFA, microbial CP (MCP) production, and cellulolytic bacteria count were determined. Compared to CS, PWSS had greater ( < 0.001) values of DM, ADL, water-soluble carbohydrates, pH, and ammonia-N but lower ( < 0.05) values of CP, ash free-NDF (NDFom), ash, nitrate, and lactic, acetic, propionic, and butyric acids concentrations. When PWSS was treated with molasses, LAB, or both, the contents of CP and lactic and acetic acids increased, whereas NDFom, ammonia-N, and butyric acid decreased ( < 0.05). Based on in vitro ruminal experiments, PWSS had greater ( < 0.05) values of GP, OMD, and MCP but lower ( < 0.05) VFA and acetic acid compared to CS. With adding molasses alone or in combination with LAB inoculants to PWSS, the values of GP

  6. Effect of addition of thermally modified cowpea protein on sensory acceptability and textural properties of wheat bread and sponge cake.

    PubMed

    Campbell, Lydia; Euston, Stephen R; Ahmed, Mohamed A

    2016-03-01

    This paper investigates the sensory acceptability and textural properties of leavened wheat bread and sponge cake fortified with cow protein isolates that had been denatured and glycated by thermal treatment. Defatted cowpea flour was prepared from cow pea beans and the protein isolate was prepared (CPI) and thermally denatured (DCPI). To prepare glycated cowpea protein isolate (GCPI) the cowpea flour slurry was heat treated before isolation of the protein. CPI was more susceptible to thermal denaturation than GCPI as determined by turbidity and sulphydryl groups resulting in greater loss of solubility. This is attributed to the higher glycation degree and higher carbohydrate content of GCPI as demonstrated by glycoprotein staining of SDS PAGE gels. Water absorption of bread dough was significantly enhanced by DCPI and to a larger extent GCPI compared to the control, resulting in softer texture. CPI resulted in significantly increased crumb hardness in baked bread than the control whereas DCPI or GCPI resulted in significantly softer crumb. Bread fortified with 4% DCPI or GCPI was similar to control as regards sensory and textural properties whereas 4% CPI was significantly different, limiting its inclusion level to 2%. There was a trend for higher sensory acceptability scores for GCPI containing bread compared DCPI. Whole egg was replaced by 20% by GCPI (3.5%) in sponge cake without affecting the sensory acceptability, whereas CPI and DCPI supplemented cakes were significantly different than the control. PMID:26471676

  7. Effect of addition of thermally modified cowpea protein on sensory acceptability and textural properties of wheat bread and sponge cake.

    PubMed

    Campbell, Lydia; Euston, Stephen R; Ahmed, Mohamed A

    2016-03-01

    This paper investigates the sensory acceptability and textural properties of leavened wheat bread and sponge cake fortified with cow protein isolates that had been denatured and glycated by thermal treatment. Defatted cowpea flour was prepared from cow pea beans and the protein isolate was prepared (CPI) and thermally denatured (DCPI). To prepare glycated cowpea protein isolate (GCPI) the cowpea flour slurry was heat treated before isolation of the protein. CPI was more susceptible to thermal denaturation than GCPI as determined by turbidity and sulphydryl groups resulting in greater loss of solubility. This is attributed to the higher glycation degree and higher carbohydrate content of GCPI as demonstrated by glycoprotein staining of SDS PAGE gels. Water absorption of bread dough was significantly enhanced by DCPI and to a larger extent GCPI compared to the control, resulting in softer texture. CPI resulted in significantly increased crumb hardness in baked bread than the control whereas DCPI or GCPI resulted in significantly softer crumb. Bread fortified with 4% DCPI or GCPI was similar to control as regards sensory and textural properties whereas 4% CPI was significantly different, limiting its inclusion level to 2%. There was a trend for higher sensory acceptability scores for GCPI containing bread compared DCPI. Whole egg was replaced by 20% by GCPI (3.5%) in sponge cake without affecting the sensory acceptability, whereas CPI and DCPI supplemented cakes were significantly different than the control.

  8. Diglycolamic acid modified silica gel for the separation of hazardous trivalent metal ions from aqueous solution.

    PubMed

    Suneesh, A S; Syamala, K V; Venkatesan, K A; Antony, M P; Vasudeva Rao, P R

    2015-01-15

    The surface of the silica gel was modified with diglycolamic acid moieties and the product (Si-DGAH) was characterized by elemental analysis, TG-DTA, (1)H and (29)Si NMR and scanning electron microscopy (SEM). The adsorption behavior of hazardous americium (III) and europium (III) in Si-DGAH was studied from aqueous nitric acid medium to examine the feasibility using the modified silica for the separation of Am(III) and Eu(III) from aqueous wastes. In this context, the effect of various parameters such as the duration of equilibration, and concentrations of europium, nitric acid, sodium nitrate and diethylenetriaminepentaacetic acid (DTPA) in aqueous phase, on the distribution coefficient (K(d)) of Am(III) and Eu(III) was investigated. The distribution coefficient of ∼10(3) mL/g (>99.9% extraction) was obtained for both Am(III) and Eu(III) at pH 3, and the K(d) values decreased with increase in the concentration of nitric acid. Rapid kinetics of extraction in the initial stages of equilibration, followed by the establishment of equilibrium occurred within 30 min. The extraction data were fitted into Langmuir adsorption model and the apparent europium extraction capacity was determined. Europium loading capacity of the sorbent was determined at various feed pH by column method. The study indicated the possibility of using diglycolamic acid-modified silica for the separation of Eu(III) and Am(III) from aqueous wastes. PMID:25454425

  9. After-ripening induced transcriptional changes of hormonal genes in wheat seeds: the cases of brassinosteroids, ethylene, cytokinin and salicylic acid.

    PubMed

    Chitnis, Vijaya R; Gao, Feng; Yao, Zhen; Jordan, Mark C; Park, Seokhoon; Ayele, Belay T

    2014-01-01

    Maintenance and release of seed dormancy is regulated by plant hormones; their levels and seed sensitivity being the critical factors. This study reports transcriptional regulation of brassinosteroids (BR), ethylene (ET), cytokinin (CK) and salicylic acid (SA) related wheat genes by after-ripening, a period of dry storage that decays dormancy. Changes in the expression of hormonal genes due to seed after-ripening did not occur in the anhydrobiotic state but rather in the hydrated state. After-ripening induced dormancy decay appears to be associated with imbibition mediated increase in the synthesis and signalling of BR, via transcriptional activation of de-etiolated2, dwarf4 and brassinosteroid signaling kinase, and repression of brassinosteroid insensitive 2. Our analysis is also suggestive of the significance of increased ET production, as reflected by enhanced transcription of 1-aminocyclopropane-1-carboxylic acid oxidase in after-ripened seeds, and tight regulation of seed response to ET in regulating dormancy decay. Differential transcriptions of lonely guy, zeatin O-glucosyltransferases and cytokinin oxidases, and pseudo-response regulator between dormant and after-ripened seeds implicate CK in the regulation of seed dormancy in wheat. Our analysis also reflects the association of dormancy decay in wheat with seed SA level and NPR independent SA signaling that appear to be regulated transcriptionally by phenylalanine ammonia lyase, and whirly and suppressor of npr1 inducible1 genes, respectively. Co-expression clustering of the hormonal genes implies the significance of synergistic and antagonistic interaction between the different plant hormones in regulating wheat seed dormancy. These results contribute to further our understanding of the molecular features controlling seed dormancy in wheat.

  10. Characterization of Triticum aestivum Abscisic Acid Receptors and a Possible Role for These in Mediating Fusairum Head Blight Susceptibility in Wheat

    PubMed Central

    Gordon, Cameron S.; Rajagopalan, Nandhakishore; Risseeuw, Eddy P.; Surpin, Marci; Ball, Fraser J.; Barber, Carla J.; Buhrow, Leann M.; Clark, Shawn M.; Page, Jonathan E.; Todd, Chris D.; Abrams, Suzanne R.; Loewen, Michele C.

    2016-01-01

    Abscisic acid (ABA) is a well-characterized plant hormone, known to mediate developmental aspects as well as both abiotic and biotic stress responses. Notably, the exogenous application of ABA has recently been shown to increase susceptibility to the fungal pathogen Fusarium graminearum, the causative agent of Fusarium head blight (FHB) in wheat and other cereals. However roles and mechanisms associated with ABA’s modulation of pathogen responses remain enigmatic. Here the identification of putative ABA receptors from available genomic databases for Triticum aestivum (bread wheat) and Brachypodium distachyon (a model cereal) are reported. A number of these were cloned for recombinant expression and their functionality as ABA receptors confirmed by in vitro assays against protein phosphatases Type 2Cs. Ligand selectivity profiling of one of the wheat receptors (Ta_PYL2DS_FL) highlighted unique activities compared to Arabidopsis AtPYL5. Mutagenic analysis showed Ta_PYL2DS_FL amino acid D180 as being a critical contributor to this selectivity. Subsequently, a virus induced gene silencing (VIGS) approach was used to knockdown wheat Ta_PYL4AS_A (and similar) in planta, yielding plants with increased early stage resistance to FHB progression and decreased mycotoxin accumulation. Together these results confirm the existence of a family of ABA receptors in wheat and Brachypodium and present insight into factors modulating receptor function at the molecular level. That knockdown of Ta_PYL4AS_A (and similar) leads to early stage FHB resistance highlights novel targets for investigation in the future development of disease resistant crops. PMID:27755583

  11. Investigation of Fatty Acid Ketohydrazone Modified Liposome's Properties as a Drug Carrier

    PubMed Central

    Hayashi, Keita; Kiriishi, Madoka; Suga, Keishi; Okamoto, Yukihiro; Umakoshi, Hiroshi

    2015-01-01

    pH-responsive liposomes were prepared by modifying the liposome with acid-cleaving amphiphiles. Palmitic ketohydrazone (P-KH) or stearic ketohydrazone (S-KH), composed of hydrophilic sugar headgroup and hydrophobic acyl chain, was used as a modifier of the DMPC liposome. Because the ketohydrazone group of P-KH or S-KH was cleaved at low pH conditions (modified liposomes was observed probably via an endocytic pathway. The membrane properties of these liposomes were characterized, focusing on the variation of both polarity (measured by Laurdan) and membrane fluidity (measured by DPH) at low pH condition. The interface of the P-KH modified liposome at acidic pH was found to become more hydrophobic and less fluidic as compared with that at neutral pH; that is, P-KH modified liposome became more rigid structure. Therefore, it seems that the P-KH modified liposome could protect encapsulated drugs from the enzymes in the lysosome. This study shows the novel approach about design of pH-responsive liposomes based on the membrane properties. PMID:26649201

  12. Nuclease stability of boron-modified nucleic acids: application to label-free mismatch detection.

    PubMed

    Reverte, Maëva; Vasseur, Jean-Jacques; Smietana, Michael

    2015-11-21

    5'-End boronic acid-modified oligonucleotides were evaluated against various nucleases at single and double stranded levels. The results show that these modifications induce a high resistance to degradation by calf-spleen and snake venom phosphodiesterases. More importantly, this eventually led to the development of a new label-free enzyme-assisted fluorescence-based method for single mismatch detection.

  13. Response of fumaric Acid addition on methanogenesis, rumen fermentation, and dry matter degradability in diets containing wheat straw and sorghum or berseem as roughage source.

    PubMed

    Sirohi, S K; Pandey, Poonam; Goel, Navneet

    2012-01-01

    An in vitro incubation system was used to evaluate effect of supplementation of fumaric acid at 0, 5, 10, and 15 mM concentration in high-, medium-, and low-fiber wheat straw containing total mixed diets with sorghum (Sorghum vulgare) and berseem clover (Trifolium alexandrinum L.) on rumen fermentation, methane production, and gas kinetics parameters. Three types of diets were prepared with different roughage and concentrate ratio (80 : 20, 50 : 50, and 20 : 80) by taking the representative samples. The roughage part composed of wheat straw (70 parts) and sorghum (30 parts) or berseem (30 parts) and the concentrate part composed of maize (33%), GNC (21%), mustard cake (12%), wheat bran (20%), deoiled rice bran (11%), mineral mixture (2%), and salt (1%). Fumaric acid was added in incubation medium to achieve final concentration of 0, 5, 10, and 15 mM. All the treatment combinations were arranged in 4 × 3 factorial designs with three replicates. It was concluded from the study that fumaric acid addition (5-15 mM) in diets varying in roughage to concentrate ratio significantly (P ≤ 0.05) reduced the methane production without affecting dry matter digestibility and maximum reduction was noticed at 5 mM concentration.

  14. Quantification of phenyllactic acid in wheat sourdough using high resolution gas chromatography-mass spectrometry.

    PubMed

    Ryan, Liam Anthony Matthew; Dal Bello, Fabio; Czerny, Michael; Koehler, Peter; Arendt, Elke Karin

    2009-02-11

    In this study, high-resolution gas chromatography-mass spectrometry (HRGC-MS) was successfully used to quantify the level of phenyllactic acid produced by Lactobacillus plantarum strains during sourdough fermentation. Investigation of samples collected during fermentation revealed that the production of phenyllactic acid occurs throughout the growth of L. plantarum in sourdough, but the highest production rate was observed during the logarithmic growth phase. The highest amount, that is, 33.47 mg of phenyllactic acid/kg of dough, was measured in sourdough fermented by the antifungal strain L. plantarum FST 1.7. Sourdoughs fermented by different L. plantarum strains contained different amounts of phenyllactic acid, thus indicating that the production is strain-dependent. Phenylacetic acid was also detected during sourdough analysis, thus showing that the HRGC-MS protocol developed is suitable for the detection not only of phenyllactic acid, but also of a broader range of phenolic acids that are highly relevant, but present in very low amounts in sourdough.

  15. Development of α-polyoxometalate-polypyrrole-Au nanoparticles modified sensor applied for detection of folic acid.

    PubMed

    Babakhanian, Arash; Kaki, Samineh; Ahmadi, Mahtab; Ehzari, Hosna; Pashabadi, Afshin

    2014-10-15

    In this work, electrochemically synthesized gold nanoparticles (AuNPs) and α-polyoxometalate (α-POM) (K7PMO2W9O39 · H2O) were simultaneously doped into electropolymerized polypyrrole (PPy) film using the cyclic voltammetry (CV) technique. Scanning electron microscopy (SEM), electrochemical impedance spectroscopy (EIS) and CVs were used to characterize the composite films. The PPy-α-POM-AuNPs modified gold (Au) electrode was used to determine folic acid (FA) using square-wave voltammetry (SWV). The modified electrode exhibited excellent electrocatalytic ability to the reduction of FA at 0.3 V (vs. SCE) with the electron transfer rate constant (ks) of 1.15 × 10(-19)s(-1). The common coexisting substances showed no interferences on the response of modified electrode to FA. The modified electrode indicated reproducible behavior and a high level stability during the experiments, making it particularly suitable for the analytical purposes.

  16. Translation of satellite tobacco necrosis virus RNA modified by (not equal to)-r-7,t-8-dihydroxy-t-9,10-epoxy-7,8,9,10-tetrahydrobenzo(a)pyrene is inhibited in a wheat germ cell-free system

    SciTech Connect

    Haas, R.; Pulkrabek, P.; Takanami, Y.; Grunberger, D.

    1983-01-01

    It has been shown that (not equal to)-r-7-,t-8-dihydroxy-t-9,10-epoxy-7,8,9,10-tetrahydrobenzo(a)pyrene (BPDE) modification of rabbit globin mRNA results in inhibition of translational initiation. In order to explore the possibility that modification of the 5' cap structure was responsible for this inhibition, the naturally non-capped mRNA from satellite tobacco necrosis virus (STNV) was reacted with BPDE and translated in a wheat germ cell-free system. The extent of modification was 1.3 and 2.9 BPDE residues/molecule. High performance liquid chromatography of the modified nucleosides from enzymatically hydrolyzed STNV RNA revealed that greater than 90% of the nucleoside adducts were substituted at the exocyclic amino group of guanosine. The translational ability of the lower and higher modified STNV, measured by incorporation of (/sup 14/C)amino acids into acid-precipitable polypeptides is inhibited by 55% and 63%, respectively. Polyacrylamide gel electrophoretic analyses of the translation products indicate that predominantly full-length coat proteins are synthesized but with the carcinogen-modified STNV the amount is reduced. On the other hand, 80S initiation complex formation is not inhibited as measured by binding of the BPDE-modified STNV to ribosomes and followed by glycerol gradient centrifugation. Under these conditions, aurintricarboxylic acid completely inhibits 80S initiation complex formation in the presence of either modified or native STNV. These results suggest that inhibition of in vitro translation of BPDE-modified STNV, in contrast to that of globin mRNA, is not at the level of initiation complex formation but possibly by premature termination of growing polypeptides.

  17. The influence of UV-irradiation on chitosan modified by the tannic acid addition.

    PubMed

    Sionkowska, A; Kaczmarek, B; Gnatowska, M; Kowalonek, J

    2015-07-01

    The influence of UV-irradiation with the wavelength 254 nm on the properties of chitosan modified by the tannic acid addition was studied. Tannic acid was added to chitosan solution in different weight ratios and after solvent evaporation thin films were formed. The properties of the films such as thermal stability, Young modulus, ultimate tensile strength, moisture content, swelling behavior before and after UV-irradiation were measured and compared. Moreover, the surface properties were studied by contact angle measurements and by the use of atomic force microscopy. The results showed that UV-irradiation caused both, the degradation of the specimen and its cross-linking. The surface of the films made of chitosan modified by the addition of tannic acid was altered by UV-irradiation.

  18. Wheat dextrin, psyllium, and inulin produce distinct fermentation patterns, gas volumes, and short-chain fatty acid profiles in vitro.

    PubMed

    Timm, Derek A; Stewart, Maria L; Hospattankar, Ashok; Slavin, Joanne L

    2010-08-01

    Dietary fiber fermentation decreases luminal pH by the production of short-chain fatty acids (SCFAs). Additional proposed physiological benefits of fiber fermentation include decreased growth of pathogenic bacteria, increased mineral absorption, and serving as an energy source for the colon epithelium. This study examined three common fiber supplements--wheat dextrin (WD) (Benefiber, Novartis Consumer Health Inc., Parsippany, NJ, USA), psyllium (PS) (Metamucil, Procter & Gamble, Cincinnati, OH, USA), and inulin (Fiber Sure, Procter & Gamble)--for pH, SCFAs, and gas production. An established in vitro fermentation model was used to simulate colonic fermentation at 0, 4, 8, 12, and 24 hours. At 24 hours, WD and inulin significantly decreased pH compared to PS. Inulin produced significantly more hydrogen and total gas. All treatments produced similar total SCFA concentrations at 24 hours; however, the rate of production was different. PS had a declining rate of SCFA production from 12 to 24 hours, whereas WD and inulin had a higher rate during that period. Fast-fermenting substrates may not provide as much SCFAs to the distal colon as slow-fermenting substrates. Differences in fermentation rate, gas production, and SCFA production observed for WD, PS, and inulin may affect their gastrointestinal tolerance and require further study.

  19. Effect of the duration of prefeeding on amino acid digestibility of wheat distillers dried grains with solubles in broiler chicken.

    PubMed

    Kluth, H; Rodehutscord, M

    2010-04-01

    The objective of this study was to determine the effect of the duration of prefeeding on prececal amino acid (AA) digestibility of wheat distillers dried grains with solubles (DDGS) in broilers. The experimental diets with DDGS at levels of 0, 10, and 20% were offered ad libitum for 7, 5, and 3 d, starting on 14, 16, and 18 d of age. Titanium dioxide was used as an indigestible marker. Six pens of 10 birds were allocated to each treatment. Digesta was sampled on a pen basis from the distal two-thirds of the intestine section between Meckel's diverticulum and 2 cm anterior to the ileo-ceca-colonic junction. Ingested and digested amounts of AA were determined for each pen. Digestibility of AA in the diets was not significantly affected by the duration of prefeeding but was significantly reduced by inclusion of DDGS. Digestibility of AA in DDGS was determined by using a linear regression approach. The digestibility of AA in DDGS ranged from 76% (Arg, 5 d of feeding) to 33% (Asp, 3 d of feeding). There was no significant effect of prefeeding time on AA digestibility of DDGS. Lysine digestibility of DDGS was 72%. The mean digestibility of the AA Arg, Cys, Ile, Leu, Lys, Met, Phe, Thr, and Val of DDGS across the 3 prefeeding times was 66%. This study gave evidence that 3 d of prefeeding a diet is sufficient in studying prececal AA digestibility in broilers when low-digestible feeds are used. PMID:20308399

  20. Chemisorptive enantioselectivity of chiral epoxides on tartaric-acid modified Pd(111): three-point bonding.

    PubMed

    Mahapatra, Mausumi; Tysoe, Wilfred T

    2015-02-21

    The chemisorption of two chiral molecules, propylene oxide and glycidol, is studied on tartaric-acid modified Pd(111) surfaces by using temperature-programmed desorption to measure adsorbate coverage. It is found that R-glycidol shows preferential enantioselective chemisorption on (S,S)-tartaric acid modified Pd(111) surfaces, while propylene oxide does not adsorb enantioselectively. The enantioselectivity of glycidol depends on the tartaric acid coverage, and is exhibited for low tartaric acid coverages indicating that the bitartrate phase is responsible for the chiral recognition. The lack of enantioselectivity when using propylene oxide as a chiral probe implies that the enantiospecific interaction between glycidol and bitartate species is due to hydrogen-bonding interactions of the -OH group of glycidol. Scanning tunneling microscopy images were collected for tartaric acid adsorbed on Pd(111) under the same experimental conditions as used for enantioselective experiments. When tartaric acid is dosed at room temperature and immediately cooled to 100 K for imaging, individual bitartrate molecules were found. Density functional theory (DFT) calculations show that bitartrate binds to Pd(111) through its carboxylate groups and the -OH groups are oriented along the long axis of the bitartrate molecule. An enantiospecific interaction is found between glycidol and bitartate species where R-glycidol binds more strongly than S-glycidol to (S,S)-bitartate species by simultaneously forming hydrogen bonds with both the hydroxyl and carboxylate groups, thereby providing three-point bonding.

  1. Adsorption of naphthalene from aqueous solution onto fatty acid modified walnut shells.

    PubMed

    Zhu, Mijia; Yao, Jun; Dong, Lifu; Sun, Jingjing

    2016-02-01

    The removal of polycyclic aromatic hydrocarbons (PAHs) from aqueous solution is challenging to environmental technologists. Agricultural waste is apparently the most attractive materials in removing PAHs because of its abundance, renewability, and economic advantage. The adsorption of PAHs (e.g., naphthalene) onto walnut shell (WNS) and its fatty acid (e.g., capric acid, lauric acid, palmitic acid, and oleic acid)-modified equivalent were investigated in this work to develop low-cost biosorbents for hydrophobic organic compounds. Compared with other modified sorbents, oleic acid graftted walnut shell (OWNS) showed the maximum partition coefficient (4330 ± 8.8 L kg(-1)) because of its lowest polarity and highest aromaticity. The adsorption capacity (7210 μg g(-1)) of OWNS at the temperature of 298 K was observed for an initial naphthalene concentration of 25 mg L(-1) with contact time of 40 h, sorbent dosage of 1 g L(-1), and in neutral condition. Furthermore, the regeneration capability of OWNS implied that it was a promising biosorbent for naphthalene removal.

  2. Adsorption of naphthalene from aqueous solution onto fatty acid modified walnut shells.

    PubMed

    Zhu, Mijia; Yao, Jun; Dong, Lifu; Sun, Jingjing

    2016-02-01

    The removal of polycyclic aromatic hydrocarbons (PAHs) from aqueous solution is challenging to environmental technologists. Agricultural waste is apparently the most attractive materials in removing PAHs because of its abundance, renewability, and economic advantage. The adsorption of PAHs (e.g., naphthalene) onto walnut shell (WNS) and its fatty acid (e.g., capric acid, lauric acid, palmitic acid, and oleic acid)-modified equivalent were investigated in this work to develop low-cost biosorbents for hydrophobic organic compounds. Compared with other modified sorbents, oleic acid graftted walnut shell (OWNS) showed the maximum partition coefficient (4330 ± 8.8 L kg(-1)) because of its lowest polarity and highest aromaticity. The adsorption capacity (7210 μg g(-1)) of OWNS at the temperature of 298 K was observed for an initial naphthalene concentration of 25 mg L(-1) with contact time of 40 h, sorbent dosage of 1 g L(-1), and in neutral condition. Furthermore, the regeneration capability of OWNS implied that it was a promising biosorbent for naphthalene removal. PMID:26517393

  3. Impact of phenazine-1-carboxylic acid upon iron speciation and microbial biomass in the rhizosphere of wheat

    NASA Astrophysics Data System (ADS)

    LeTourneau, M.; Marshall, M.; Grant, M.; Freeze, P.; Cliff, J. B.; Lai, B.; Strawn, D. G.; Thomashow, L. S.; Weller, D. M.; Harsh, J. B.

    2015-12-01

    Phenazine-1-carboxylic acid (PCA) is a redox-active antibiotic produced by diverse bacterial taxa, and has been shown to facilitate interactions between biofilms and iron (hydr)oxides in culture systems (Wang et al. 2011, J Bacteriol 192: 365). Because rhizobacterial biofilms are a major sink for plant-derived carbon and source for soil organic matter (SOM), and Fe (hydr)oxides have reactive surfaces that influence the stability of microbial biomass and SOM, PCA-producing rhizobacteria could influence soil carbon fluxes. Large populations of Pseudomonas fluorescens strains producing PCA in concentrations up to 1 μg/g root have been observed in the rhizosphere of non-irrigated wheat fields covering 1.56 million hectares of central Washington state. This is one of the highest concentrations ever reported for a natural antibiotic in a terrestrial ecosystem (Mavrodi et al. 2012, Appl Environ Microb 78: 804). Microscopic comparisons of PCA-producing (PCA+) and non-PCA-producing (PCA-) rhizobacterial colony morphologies, and comparisons of Fe extractions from rhizosphere soil inoculated with PCA+ and PCA- strains suggest that PCA promotes biofilm development as well as dramatic Fe transformations throughout the rhizosphere (unpublished data). In order to illustrate PCA-mediated interactions between biofilms and Fe (hydr)oxides in the rhizosphere, identify the specific Fe phases favored by PCA, and establish the ramifications for stability and distribution of microbial biomass and SOM, we have collected electron micrographs, X-ray fluorescence images, X-ray absorption near-edge spectra, and secondary-ion mass spectrometry images of wheat root sections inoculated with 15N-labelled PCA+ or PCA- rhizobacteria. These images and spectra allow us to assess the accumulation, turnover, and distribution of microbial biomass, the associations between Fe and other nutrients such as phosphorus, and the redox status and speciation of iron in the presence and absence of PCA. This

  4. Seasonal variation of the effect of extremely diluted agitated gibberellic acid (10e-30) on wheat stalk growth: a multiresearcher study.

    PubMed

    Endler, Peter Christian; Matzer, Wolfgang; Reich, Christian; Reischl, Thomas; Hartmann, Anna Maria; Thieves, Karin; Pfleger, Andrea; Hoföcker, Jürgen; Lothaller, Harald; Scherer-Pongratz, Waltraud

    2011-01-01

    The influence of a homeopathic high dilution of gibberellic acid on wheat growth was studied at different seasons of the year. Seedlings were allowed to develop under standardized conditions for 7 days; plants were harvested and stalk lengths were measured. The data obtained confirm previous findings, that ultrahigh diluted potentized gibberellic acid affects stalk growth. Furthermore, the outcome of the study suggests that experiments utilizing the bioassay presented should best be performed in autumn season. In winter and spring, respectively, no reliable effects were found.

  5. Chemical force titrations of amine- and sulfonic acid-modified poly(dimethylsiloxane).

    PubMed

    Wang, Bin; Oleschuk, Richard D; Horton, J Hugh

    2005-02-15

    Chemical force titrations-measurements of the adhesive interaction between a pair of suitably chemically modified atomic force microscopy (AFM) tip and sample surfaces as a function of pH-have been carried out for various combinations of silanol, amine, carboxylic acid, and sulfonic acid functional groups on both tip and sample. The primary surface material studied was poly(dimethylsiloxane) (PDMS). Surface modification was carried out using a plasma oxidation process to form silanol sites; further modification with amine or sulfonic acid sites was carried out by reaction of the silanol sites with the appropriate trialkoxysilane derivative. AFM tips were also modified using trialkoxysilane compounds. In the cases of tip/sample combinations with the same functional group on each, surface pK(1/2) values could be determined. In several "mixed" tip/sample combinations, a peak appeared in the titration curve midway between the surface pK(1/2) values of the tip and sample, consistent with an ionic H-bonding model for the interactions. The amine/sulfonic acid pair showed more complex behavior; the amine-terminated tip/sulfonic acid-terminated PDMS surface force titration curve consisted of two peaks centered at pH 4 and pH 8. Reversing the tip/sample pair resulted in the peak positions being shifted upward by 1.0 pH unit. The peak appearing at lower pH is assigned to electrostatic interactions between the two oppositely charged surfaces, whereas the higher pH peak is believed to arise due to ionic H-bonding interactions. AFM images show the effects on surface patterning of amine- and sulfonic acid-modified PDMS surfaces that have undergone two different oxidation methods (air plasma oxidation and Tesla coil oxidation). The surface morphologies of freshly prepared and 24 h aged air plasma oxidized PDMS are also discussed in this study.

  6. Highly efficient inverted organic solar cells using amino acid modified indium tin oxide as cathode

    SciTech Connect

    Li, Aiyuan; Nie, Riming; Deng, Xianyu; Wei, Huaixin; Li, Yanqing; Tang, Jianxin; Zheng, Shizhao; Wong, King-Young

    2014-03-24

    In this paper, we report that highly efficient inverted organic solar cells were achieved by modifying the surface of indium tin oxide (ITO) using an amino acid, Serine (Ser). With the modification of the ITO surface, device efficiency was significantly enhanced from 0.63% to 4.17%, accompanied with an open circuit voltage (Voc) that was enhanced from 0.30 V to 0.55 V. Ultraviolet and X-ray photoelectron spectroscopy studies indicate that the work function reduction induced by the amino acid modification resulting in the decreased barrier height at the ITO/organic interface played a crucial role in the enhanced performances.

  7. Oxidation mechanism of formic acid on the bismuth adatom-modified Pt(111) surface.

    PubMed

    Perales-Rondón, Juan Victor; Ferre-Vilaplana, Adolfo; Feliu, Juan M; Herrero, Enrique

    2014-09-24

    In order to improve catalytic processes, elucidation of reaction mechanisms is essential. Here, supported by a combination of experimental and computational results, the oxidation mechanism of formic acid on Pt(111) electrodes modified by the incorporation of bismuth adatoms is revealed. In the proposed model, formic acid is first physisorbed on bismuth and then deprotonated and chemisorbed in formate form, also on bismuth, from which configuration the C-H bond is cleaved, on a neighbor Pt site, yielding CO2. It was found computationally that the activation energy for the C-H bond cleavage step is negligible, which was also verified experimentally. PMID:25188779

  8. Chelation Properties of Modified Humic Acids Toward Some Trivalent Lanthanide Ions

    SciTech Connect

    Yaghmour, Remah N.; Khalili, Fawwaz I.; Mubarak, Mohammad S.

    2007-05-09

    Three kinds of humic acids, Fluka (I), Fluka (II), and Ega-chemie (III) were modified through condensation with formaldehyde to afford polymers I, II, and III, respectively. The chelation behavior of these modified humic acids polymers towards the trivalent lanthanide metal-ions, La3+, Ce3+, Nd3+, Sm3+, and Gd3+ was studied by a batch equilibration technique at 25 deg. C as a function of contact time, pH, counter ion and counter ion concentration. The highest metal-ion uptake of the three polymers was achieved at pH 7.0 and by using perchlorate as a counter ion. Results of the study have revealed that polymer II has the highest metal-ion uptake capacity, and that the metal-ion uptake falls in the order: Gd3+ > Sm3+ > Nd3+ > La3+ {approx_equal} Ce3+.

  9. Preparation and characterization of glycyrrhetinic acid-modified stearic acid-grafted chitosan micelles.

    PubMed

    Chen, Qian; Sun, Yong; Wang, Jiangjun; Yan, Guowen; Cui, Zhaoyuan; Yin, Hongli; Wei, Haitian

    2015-01-01

    Stearic acid-grafted chitosan (CS-SA) and glycyrrhetinic acid-conjugated stearic acid-grafted chitosan (GA-CS-SA) were synthesized and were further used for the preparation of micelles. The substitution degree (SD) of SA and GA on CS was measured. The physicochemical properties of CS-SA and GA-CS-SA micelles such as critical micelle concentration (CMC), aggregation number of hydrophobic micro-domain (AN), particle size, zeta potential, and morphology were also determined. The CMC of GA-CS-SA was about 17.49 μg/mL, which was relatively low. Its AN was 2.09. The GA-CS-SA micelles showed spherical shape with mean diameter of 121.1 nm and had positive charge, which suggested that GA-CS-SA could be a good carrier of cancer drug.

  10. The study of interaction of modified fatty acid with 99mTc in alcoholic media

    NASA Astrophysics Data System (ADS)

    Skuridin, V. S.; Stasyuk, E. S.; Varlamova, N. V.; Nesterov, E. A.; Sinilkin, I. G.; Sadkin, V. L.; Rogov, A. S.; Ilina, E. A.; Larionova, L. A.; Sazonova, S. I.; Zelchan, R. V.; Villa, N. E.

    2016-08-01

    The paper presents the results of laboratory research aimed at the development of methods of synthesis of new radiodiagnostic agents based on modified fatty acid labelled with technetium-99m intended for scintigraphic evaluation of myocardial metabolism. In particular, the interaction of substance with 99mTc in alcoholic media and the use of ethanol as solvent in the synthesis of the radiopharmaceutical were studied.

  11. Standardized ileal digestibility of amino acids in alfalfa meal, sugar beet pulp, and wheat bran compared to wheat and protein ingredients for growing pigs.

    PubMed

    Eklund, M; Rademacher, M; Sauer, W C; Blank, R; Mosenthin, R

    2014-03-01

    A total of 11 (8 + 3 for replacement) barrows with an initial BW of 23 kg and fitted with a simple T-cannula at the distal ileum were used in 2 consecutive experiments (Exp. 1 and Exp. 2) to determine the standardized ileal digestibility (SID) of AA in 7 assay feed ingredients according to 2 consecutive duplicated 4 × 4 Latin square designs. In Exp. 1, 3 corn starch-based assay diets were formulated to contain 170 g CP/kg (as-fed basis) from either soybean meal (SBM), canola meal (CM), or meat-and-bone meal (MBM) and 1 assay diet that contained 136 g CP/kg (as-fed basis) from wheat as commonly used feed ingredients for pigs. In Exp. 2, the pigs were fed 4 assay diets formulated to contain 170 g CP/kg (as-fed basis) from either the same SBM as in Exp. 1 or a combination of this SBM and alfalfa meal (AM), sugar beet pulp (SB), or wheat bran (WB) to compare the SID of AA in these feed ingredients with those used in Exp. 1. The SID of AA in CM was lower compared to SBM (P < 0.05) with intermediate values for MBM and wheat. Among fiber rich feed ingredients, SID values were lower in SB compared to WB (P < 0.05) with intermediate values for AM. In AM, SID values ranged between 29 and 45% for Lys, Cys, Thr, and Phe and between 51 and 71% for Arg, His, Ile, Leu, Met, and Val. In SB, SID values ranged between -21 and 46% for Cys, Thr, Phe, and Val and between 51 and 61% for Arg, His, Ile, Leu, Lys, and Met. In WB, SID values were between 55 and 64% for Lys, Cys, Phe, Thr, and Val and between 68 and 80% for Arg, His, Ile, Leu, and Met. The SID values in WB, SB, and AM provided in the present study may improve diet formulation when these feed ingredients are used in diet formulation for pigs.

  12. In vitro corrosion and biocompatibility study of phytic acid modified WE43 magnesium alloy

    NASA Astrophysics Data System (ADS)

    Ye, C. H.; Zheng, Y. F.; Wang, S. Q.; Xi, T. F.; Li, Y. D.

    2012-02-01

    Phytic acid (PA) conversion coating on WE43 magnesium alloy was prepared by the method of immersion. The influences of phytic acid solution with different pH on the microstructure, properties of the conversion coating and the corrosion resistance were investigated by SEM, FTIR and potentiodynamic polarization method. Furthermore, the biocompatibility of different pH phytic acid solution modified WE43 magnesium alloys was evaluated by MTT and hemolysis test. The results show that PA can enhance the corrosion resistance of WE43 magnesium especially when the pH value of modified solution is 5 and the cytotoxicity of the PA coated WE43 magnesium alloy is much better than that of the bare WE43 magnesium alloy. Moreover, all the hemolysis rates of the PA coated WE43 Mg alloy were lower than 5%, indicating that the modified Mg alloy met the hemolysis standard of biomaterials. Therefore, PA coating is a good candidate to improve the biocompatibility of WE43 magnesium alloy.

  13. Molecular interactions in biomineralized hydroxyapatite amino acid modified nanoclay: in silico design of bone biomaterials.

    PubMed

    Katti, Dinesh R; Sharma, Anurag; Ambre, Avinash H; Katti, Kalpana S

    2015-01-01

    A simulations driven approach to design of a novel biomaterial nanocomposite system is described in this study. Nanoclays modified with amino acids (OMMT) were used to mineralize hydroxyapatite (HAP), mimicking biomineralization. Representative models of organically modified montmorillonite clay (OMMT) and OMMT-hydroxyapatite (OMMT-HAP) were constructed using molecular dynamics and validated using X-ray Diffraction (XRD), Fourier Transforms Infrared (FTIR) spectroscopy and Transmission Electron Microscopy (TEM). Attractive interactions exist between Ca atoms of HAP and C=O group of aminovaleric acid, indicating chelate formation in OMMT-HAP. Interaction energy maps describe molecular interactions among different constituents and their quantitative contributions in the OMMT and OMMT-HAP systems at both parallel and perpendicular orientations. High attractive and high repulsive interactions were found between PO4(3-) and MMT clay as well as aminovaleric molecules in OMMT-HAP perpendicular and parallel models. Large non-bonded interactions in OMMT-HAP indicate influence of neighboring environment on PO4(3-) in in situ HAPclay. Extensive hydrogen bonds were observed between functional hydrogen atoms of modifier and MMT clay in OMMT-HAP as compared to OMMT. Thus, HAP interacts with clay through the aminovaleric acid. This computational study provides a framework for materials design and selection for biomaterials used in tissue engineering and other areas of regenerative medicine. PMID:25491979

  14. Chlorsulfuron modifies biosynthesis of acyl Acid substituents of sucrose esters secreted by tobacco trichomes.

    PubMed

    Kandra, L; Wagner, G J

    1990-11-01

    Sucrose esters and duvatrienediol diterpenes are principal constituents formed in and secreted outside head cells of trichomes occurring on surfaces of Nicotiana tabacum. Using trichome-bearing epidermal peels prepared from midveins of N. tabacum cv T.I. 1068 leaves, we found that chlorsulfuron reduced and modified radiolabeling of sucrose ester acyl acids derived from branched-chain amino acid metabolism. The herbicide did not effect formation and exudation of diterpenes which are products of isoprenoid metabolism. Treatment with 1.0 micromolar chlorsulfuron affected 8.5- and 6.3-fold reductions in radiolabeling of methylvaleryl and methylbutyryl groups of sucrose esters, respectively, and concomitant increases of 9- and 9.8-fold in radiolabeling of straight chain valeryl and butyryl groups, respectively. These results and others indicate that inhibition of acetolactate synthase causes an accumulation of 2-oxo-butyric acid that is utilized by enzymes common to Leu biosynthesis to form 2-oxo-valeric acid. Coenzyme A (CoA) activation of this keto acid gives rise to butyryl CoA, which is utilized to form butyryl containing sucrose esters. Alternatively, reutilization of 2-oxo-valeric acid by the same enzymes followed by CoA activation leads to valeryl containing sucrose esters. We propose that in trichome secretory cells synthase, isomerase and dehydrogenase enzymes which catalyze Leu synthesis/degredation in most tissues, convert iso-branched, anteiso-branched and straight-chain keto acids in the formation of sucrose ester acyl groups. PMID:16667871

  15. Chlorsulfuron Modifies Biosynthesis of Acyl Acid Substituents of Sucrose Esters Secreted by Tobacco Trichomes

    PubMed Central

    Kandra, Lili; Wagner, George J.

    1990-01-01

    Sucrose esters and duvatrienediol diterpenes are principal constituents formed in and secreted outside head cells of trichomes occurring on surfaces of Nicotiana tabacum. Using trichome-bearing epidermal peels prepared from midveins of N. tabacum cv T.I. 1068 leaves, we found that chlorsulfuron reduced and modified radiolabeling of sucrose ester acyl acids derived from branched-chain amino acid metabolism. The herbicide did not effect formation and exudation of diterpenes which are products of isoprenoid metabolism. Treatment with 1.0 micromolar chlorsulfuron affected 8.5- and 6.3-fold reductions in radiolabeling of methylvaleryl and methylbutyryl groups of sucrose esters, respectively, and concomitant increases of 9- and 9.8-fold in radiolabeling of straight chain valeryl and butyryl groups, respectively. These results and others indicate that inhibition of acetolactate synthase causes an accumulation of 2-oxo-butyric acid that is utilized by enzymes common to Leu biosynthesis to form 2-oxo-valeric acid. Coenzyme A (CoA) activation of this keto acid gives rise to butyryl CoA, which is utilized to form butyryl containing sucrose esters. Alternatively, reutilization of 2-oxo-valeric acid by the same enzymes followed by CoA activation leads to valeryl containing sucrose esters. We propose that in trichome secretory cells synthase, isomerase and dehydrogenase enzymes which catalyze Leu synthesis/degredation in most tissues, convert iso-branched, anteiso-branched and straight-chain keto acids in the formation of sucrose ester acyl groups. PMID:16667871

  16. Ethylene limits abscisic acid- or soil drying-induced stomatal closure in aged wheat leaves.

    PubMed

    Chen, Lin; Dodd, Ian C; Davies, William J; Wilkinson, Sally

    2013-10-01

    The mechanism of age-induced decreased stomatal sensitivity to abscisic acid (ABA) and soil drying has been explored here. Older, fully expanded leaves partly lost their ability to close stomata in response to foliar ABA sprays, and soil drying which stimulated endogenous ABA production, while young fully expanded leaves closed their stomata more fully. However, ABA- or soil drying-induced stomatal closure of older leaves was partly restored by pretreating plants with 1-methylcyclopropene (1-MCP), which can antagonize ethylene receptors, or by inoculating soil around the roots with the rhizobacterium Variovorax paradoxus 5C-2, which contains 1-aminocyclopropane-1-carboxylic acid (ACC)-deaminase. ACC (the immediate biosynthetic precursor of ethylene) sprays revealed higher sensitivity of stomata to ethylene in older leaves than younger leaves, despite no differences in endogenous ACC concentrations or ethylene emission. Taken together, these results indicate that the relative insensitivity of stomatal closure to ABA and soil drying in older leaves is likely due to altered stomatal sensitivity to ethylene, rather than ethylene production. To our knowledge, this is the first study to mechanistically explain diminished stomatal responses to soil moisture deficit in older leaves, and the associated reduction in leaf water-use efficiency.

  17. Comparative effects of wild type Stenotrophomonas maltophilia and its indole acetic acid-deficient mutants on wheat.

    PubMed

    Hassan, T U; Bano, A

    2016-09-01

    The present investigation evaluated the role of Stenotrophomonas maltophilia and its IAA-deficient mutant on soil health and plant growth under salinity stress in the presence of tryptophan. In the first phase, S. maltophilia isolated from roots of the halo- phytic herb, Cenchrus ciliaris was used as bio-inoculant on wheat grown in saline sodic soil. A field experiment was conducted at Soil Salinity Research Institute during 2010-2011. Treatments included seed inoculation with S. maltophilia with or without tryptophan; uninoculated untreated plants were taken as control. An aqueous solution of tryptophan was added to rhizosphere soil at 1 μg l(_1) after seed germination. Inoculation with S. maltophilia significantly increased soil organic matter, enhanced (20-30%) availability of P, K, Ca and NO3 -N and decreased Na content and electrical conductivity of rhizosphere soil. Plant height, fresh weight, proline and phytohormone content of leaves were increased 30-40% over the control. Activities of superoxide dismutase (SOD) and peroxidase (POD) were 40-50% higher than control. Addition of tryptophan further augmented (10-15%) growth parameters, whereas NO3 -N, P, K and Ca content, proline content and SOD and POD increased 20-30%. In a second phase, indoleacetic acid (IAA)-deficient mutants of S. maltophilia were constructed and evaluated for conversion of tryptophan to IAA at the University of Calgary, Canada, during 2013-2014. About 1800 trans-conjugants were constructed that were unable to produce IAA in the presence of tryptophan. The results suggest that tryptophan assisted S. maltophilia in the amelioration of salt stress, and that IAA played positive role in induction of salt tolerance. PMID:27263526

  18. Rope-producing strains of Bacillus spp. from wheat bread and strategy for their control by lactic acid bacteria.

    PubMed

    Pepe, Olimpia; Blaiotta, Giuseppe; Moschetti, Giancarlo; Greco, Teresa; Villani, Francesco

    2003-04-01

    Two types of white wheat bread (high- and low-type loaves) were investigated for rope spoilage. Thirty of the 56 breads tested developed rope spoilage within 5 days; the high-type loaves were affected by rope spoilage more than the low-type loaves. Sixty-one Bacillus strains were isolated from ropy breads and were characterized on the basis of their phenotypic and genotypic traits. All of the isolates were identified as Bacillus subtilis by biochemical tests, but molecular assays (randomly amplified polymorphic DNA PCR assay, denaturing gradient gel electrophoresis analysis, and sequencing of the V3 region of 16S ribosomal DNA) revealed greater Bacillus species variety in ropy breads. In fact, besides strains of B. subtilis, Bacillus licheniformis, Bacillus cereus, and isolates of Bacillus clausii and Bacillus firmus were also identified. All of the ropy Bacillus isolates exhibited amylase activity, whereas only 32.4% of these isolates were able to produce ropiness in bread slices after treatment at 96 degrees C for 10 min. Strains of lactic acid bacteria previously isolated from sourdough were first selected for antirope activity on bread slices and then used as starters for bread-making experiments. Prevention of growth of approximately 10(4) rope-producing B. subtilis G1 spores per cm(2) on bread slices for more than 15 days was observed when heat-treated cultures of Lactobacillus plantarum E5 and Leuconostoc mesenteroides A27 were added. Growth of B. subtilis G1 occurred after 7 days in breads started with Saccharomyces cerevisiae T22, L. plantarum E5, and L. mesenteroides A27. PMID:12676716

  19. Effects of xylanase and citric acid on the performance, nutrient retention, and characteristics of gastrointestinal tract of broilers fed low-phosphorus wheat-based diets.

    PubMed

    Esmaeilipour, O; Shivazad, M; Moravej, H; Aminzadeh, S; Rezaian, M; van Krimpen, M M

    2011-09-01

    An experiment was conducted to study the effects of xylanase and citric acid on the performance, nutrient retention, jejunal viscosity, and size and pH of the gastrointestinal tract of broilers fed a low-P wheat-based diet. The experiment was conducted as a 2 × 3 factorial arrangement with 2 levels of xylanase (0 and 200 mg/kg) and 3 levels of citric acid (0, 20, and 40 g/kg). Each of the 6 dietary treatments was fed to 4 replicate pens (17 birds/pen) from 0 to 24 d of age. Chromium oxide (3 g/kg) was added to the diets as an indigestible marker to determine the apparent nutrient retention. No interaction effect was observed between xylanase and citric acid in any measured response. Xylanase did not affect feed intake but significantly increased BW gain by 3.6% (P < 0.05) from 1 to 24 d of age and improved G:F by 3.9% (P < 0.01). The inclusion of 40 g/kg of citric acid decreased (P < 0.01) BW gain and feed intake by 8.6 and 12.5%, respectively. The inclusion of 20 and 40 g/kg of citric acid improved G:F by 2.3 and 4.5% (P < 0.05), respectively. Xylanase significantly decreased the viscosity of digesta and improved the retention of DM, CP, and energy, but did not have a significant effect on the retention of fat and P. Inclusion of 20 and 40 g/kg of citric acid in the diets increased P retention by 15.8 and 16.3% (P < 0.01), respectively. Citric acid significantly decreased the pH of crop contents (P < 0.05). In conclusion, citric acid, at the 40 g/kg inclusion level, reduced feed intake and BW gain but improved G:F and P retention. Xylanase decreased digesta viscosity, increased nutrient retention, and consequently improved the performance of broilers fed the low-P wheat-based diet. Thus, adding 20 g/kg of citric acid, especially in the starter period, and 200 mg/kg of xylanase to low-P wheat-based diets can be helpful.

  20. ASCORBIC ACID CONTROLS MYCOSPHAERELLA GRAMINICOLA IN BREAD AND DURUM WHEAT THROUGH DIRECT EFFECT ON THE PATHOGEN AND INDIRECT ACTION VIA PLANT DEFENCE.

    PubMed

    Somai-Jemmali, L; Magnin-Robert, M; Randoux, B; Siah, A; Tisserant, B; Halama, P; Reignault, Ph; Hamada, W

    2015-01-01

    Septoria tritici blotch (STB) caused by Mycosphaerella graminicola is one of the most devastating foliar diseases on wheat. Due to the emergence of fungicide-resistant M. graminicola strains and in an effort to reduce the impact of pesticides on the environment, considerable interest has been devoted to alternative control strategies. The use of natural products, especially through a defense-activating effect on the host, could be considered. Acid ascorbic (AA) is synthesized by plants and most animal cells with antioxidant properties. This study aimed at: (i) assessing the protective effect of an AA-based product on bread (BW) and durum (DW) wheat (Triticum aestivum and T. durum, respectively) susceptible cultivars against M. graminicola and (ii) investigating the mechanisms involved in wheat protection. Therefore, the foliar application of a formulated AA-based product (50 mg L-) on 3-week-old wheat plants reduced the infection level by more than 75% for both BW and DW. In vitro experiments revealed that AA induced a strong inhibition of spore germination (at 50 mg L.(-1)) and hyphal growth (at 16 mg L.(-1)) for both M. graminicola strains, infecting either BW or DW. Used as a preventive foliar spray on wheat leaves, microscopic observations revealed that AA inhibits in planta spore germination, hyphal growth, leaf penetration, substomatal colonization and eventually sporulation. Moreover, AA treatment also decreased fungal protease and cell wall degrading enzyme activities, putative pathogenicity determinants of M. graminicola. In addition to these effects on the fungus, AA induced defence reactions in both BW and DW. Indeed, in non-inoculated context, eliciting effect was observed on (i) stimulation of enzymatic activities such as lipoxygenase, peroxydase and catalase and (ii) transcript accumulation of genes encoding for pathogenesis-related (PR) proteins (chitinase class IV, peroxidase). In inoculated condition, accumulation of H2O2 and phenolic compounds

  1. ASCORBIC ACID CONTROLS MYCOSPHAERELLA GRAMINICOLA IN BREAD AND DURUM WHEAT THROUGH DIRECT EFFECT ON THE PATHOGEN AND INDIRECT ACTION VIA PLANT DEFENCE.

    PubMed

    Somai-Jemmali, L; Magnin-Robert, M; Randoux, B; Siah, A; Tisserant, B; Halama, P; Reignault, Ph; Hamada, W

    2015-01-01

    Septoria tritici blotch (STB) caused by Mycosphaerella graminicola is one of the most devastating foliar diseases on wheat. Due to the emergence of fungicide-resistant M. graminicola strains and in an effort to reduce the impact of pesticides on the environment, considerable interest has been devoted to alternative control strategies. The use of natural products, especially through a defense-activating effect on the host, could be considered. Acid ascorbic (AA) is synthesized by plants and most animal cells with antioxidant properties. This study aimed at: (i) assessing the protective effect of an AA-based product on bread (BW) and durum (DW) wheat (Triticum aestivum and T. durum, respectively) susceptible cultivars against M. graminicola and (ii) investigating the mechanisms involved in wheat protection. Therefore, the foliar application of a formulated AA-based product (50 mg L-) on 3-week-old wheat plants reduced the infection level by more than 75% for both BW and DW. In vitro experiments revealed that AA induced a strong inhibition of spore germination (at 50 mg L.(-1)) and hyphal growth (at 16 mg L.(-1)) for both M. graminicola strains, infecting either BW or DW. Used as a preventive foliar spray on wheat leaves, microscopic observations revealed that AA inhibits in planta spore germination, hyphal growth, leaf penetration, substomatal colonization and eventually sporulation. Moreover, AA treatment also decreased fungal protease and cell wall degrading enzyme activities, putative pathogenicity determinants of M. graminicola. In addition to these effects on the fungus, AA induced defence reactions in both BW and DW. Indeed, in non-inoculated context, eliciting effect was observed on (i) stimulation of enzymatic activities such as lipoxygenase, peroxydase and catalase and (ii) transcript accumulation of genes encoding for pathogenesis-related (PR) proteins (chitinase class IV, peroxidase). In inoculated condition, accumulation of H2O2 and phenolic compounds

  2. Exposure or release of ferulic acid from wheat aleurone: impact on its antioxidant capacity.

    PubMed

    Rosa, Natalia N; Dufour, Claire; Lullien-Pellerin, Valérie; Micard, Valérie

    2013-12-01

    The relationship between the aleurone cell integrity and the exposure or release of bioavailable ferulic acid (FA) with the antioxidant capacity of aleurone in in vitro and under simulated gastric conditions was explored. The antioxidant capacity of aleurone was increased by around 2-fold when its median particle size was reduced to under 50 μm. The opening of aleurone cells increased the physical exposure of FA bound to the insoluble polysaccharides, which seemed to be responsible of the increased antioxidant capacity. Synergistic combination of xylanase and feruloyl esterase was found to be the most efficient enzymatic treatment releasing up to 86% of total FA in bioaccessible forms. This enzymatic treatment significantly enhanced the radical scavenging activity of aleurone by up to 4-fold, which overlapped the overall antioxidant potential estimated from the total content of FA in aleurone. The improvement in the antioxidant capacity of aleurone was also observed in the simulated gastric digestion by inhibition of lipid oxidation.

  3. β-Aminobutyric acid increases abscisic acid accumulation and desiccation tolerance and decreases water use but fails to improve grain yield in two spring wheat cultivars under soil drying.

    PubMed

    Du, Yan-Lei; Wang, Zhen-Yu; Fan, Jing-Wei; Turner, Neil C; Wang, Tao; Li, Feng-Min

    2012-08-01

    A pot experiment was conducted to investigate the effect of the non-protein amino acid, β-aminobutyric acid (BABA), on the homeostasis between reactive oxygen species (ROS) and antioxidant defence during progressive soil drying, and its relationship with the accumulation of abscisic acid (ABA), water use, grain yield, and desiccation tolerance in two spring wheat (Triticum aestivum L.) cultivars released in different decades and with different yields under drought. Drenching the soil with 100 µM BABA increased drought-induced ABA production, leading to a decrease in the lethal leaf water potential (Ψ) used to measure desiccation tolerance, decreased water use, and increased water use efficiency for grain (WUEG) under moderate water stress. In addition, at severe water stress levels, drenching the soil with BABA reduced ROS production, increased antioxidant enzyme activity, and reduced the oxidative damage to lipid membranes. The data suggest that the addition of BABA triggers ABA accumulation that acts as a non-hydraulic root signal, thereby closing stomata, and reducing water use at moderate stress levels, and also reduces the production of ROS and increases the antioxidant defence enzymes at severe stress levels, thus increasing the desiccation tolerance. However, BABA treatment had no effect on grain yield of wheat when water availability was limited. The results suggest that there are ways of effectively priming the pre-existing defence pathways, in addition to genetic means, to improve the desiccation tolerance and WUEG of wheat.

  4. A comparison of the levels of hydroxamic acids in Aegilops speltoides and a hexaploid wheat and effects on Rhopalosiphum padi behaviour and fecundity.

    PubMed

    Elek, Henriett; Smart, Lesley; Ahmad, S; Anda, Angéla; Werner, C P; Pickett, J A

    2014-03-01

    Hydroxamic acids (HAs) are plant secondary metabolites produced by certain cereals, which have been found to be toxic to pest aphids in artificial diet assays. Previous studies have shown that tetraploid and hexaploid wheat varieties, the leaf tissues of which contained higher levels of these compounds than used in artificial diets, did not reduce aphid settling or fecundity. This current study reports findings on a high HA producing B genome accession of the diploid ancestor of wheat, Aegilops speltoides. We found that this accession does have a negative impact on aphid host selection and substantially reduces nymph production. Whole leaf tissue assays showed very high levels of HAs, well in excess of the toxic level determined in the artificial diet assays. Extraction of the apoplast fluid (AF) from this accession showed that the HA level is much lower than that of the whole tissue, but is still close to the artificial diet toxic level. Furthermore the HA level in the AF increases in response to aphid feeding. These observations could explain why hexaploid wheat remains susceptible to aphids, despite having whole leaf tissue HA levels in excess of the toxic levels determined in artificial diets.

  5. Characterizing Corrosion Effects of Weak Organic Acids Using a Modified Bono Test

    NASA Astrophysics Data System (ADS)

    Zhou, Yuqin; Turbini, Laura J.; Ramjattan, Deepchand; Christian, Bev; Pritzker, Mark

    2013-12-01

    To meet environmental requirements and achieve benefits of cost-effective manufacturing, no-clean fluxes (NCFs) or low-solids fluxes have become popular in present electronic manufacturing processes. Weak organic acids (WOAs) as the activation ingredients in NCFs play an important role, especially in the current lead-free and halogen-free soldering technology era. However, no standard or uniform method exists to characterize the corrosion effects of WOAs on actual metallic circuits of printed wiring boards (PWBs). Hence, the development of an effective quantitative test method for evaluating the corrosion effects of WOAs on the PWB's metallic circuits is imperative. In this paper, the modified Bono test, which was developed to quantitatively examine the corrosion properties of flux residues, is used to characterize the corrosion effects of five WOAs (i.e., abietic acid, succinic acid, glutaric acid, adipic acid, and malic acid) on PWB metallic circuits. Experiments were performed under three temperature/humidity conditions (85°C/85% RH, 60°C/93% RH, and 40°C/93% RH) using two WOA solution concentrations. The different corrosion effects among the various WOAs were best reflected in the testing results at 40°C and 60°C. Optical microscopy was used to observe the morphology of the corroded copper tracks, and scanning electron microscopy (SEM) energy-dispersive x-ray (EDX) characterization was performed to determine the dendrite composition.

  6. On-site cellulase production by Trichoderma reesei 3EMS35 mutant and same vessel saccharification and fermentation of acid treated wheat straw for ethanol production.

    PubMed

    Khokhar, Zia-Ullah; Syed, Qurat-Ul-Ain; Wu, Jing; Athar, Muhammad Amin

    2014-01-01

    Bioethanol production from lignocellulosic raw materials involves process steps like pre-treatment, enzymatic hydrolysis, fermentation and distillation. In this study, wheat straw was explored as feedstock for on-site cellulase production by T. reesei 3EMS35 mutant, and as a substrate for second generation bioethanol production from baker yeast. Scanning electron microscopy (SEM) and X-ray diffractography (XRD) of untreated wheat straw (UWS) and acid treated wheat straw (TWS) were done to understand the structural organization and changes in the cellulase accessibility and reactivity. The effect of delignification and structural modification for on-site cellulase enzyme production was comparably studied. The efficiency of crude cellulase enzyme for digestion of UWS and TWS and then production of ethanol from TWS was studied using same-vessel saccharification and fermentation (SVSF) technique, both in shaking flasks as well as in fermenters. Two different methods of operation were tested, i.e. the UWSEnz method, where UWS was used for on-site enzyme production, and TWSEnz method where TWS was applied as substrate for cellullase production. Results obtained showed structural modifications in cellulose of TWS due to delignification, removal of wax and change of crystallinity. UWS was better substrate than TWS for cellulase production due to the fact that lignin did not hinder the enzyme production by fungus but acted as a booster. On-site cellulase enzyme produced by T. reesei 3EMS35 mutant hydrolyzed most of cellulose (91 %) in TWS within first 24 hrs. Shake flasks experiments showed that ethanol titers and yields with UWSEnz were 2.9 times higher compared to those obtained with TWSEnz method respectively. Comparatively, titer of ethanol in shake flask experiments was 10 % higher than this obtained in 3 L fermenter with UWSEnz. Outcomes from this investigation clearly demonstrated the potential of on-site cellulase enzyme production and SVSF for ethanol production

  7. On-site cellulase production by Trichoderma reesei 3EMS35 mutant and same vessel saccharification and fermentation of acid treated wheat straw for ethanol production.

    PubMed

    Khokhar, Zia-Ullah; Syed, Qurat-Ul-Ain; Wu, Jing; Athar, Muhammad Amin

    2014-01-01

    Bioethanol production from lignocellulosic raw materials involves process steps like pre-treatment, enzymatic hydrolysis, fermentation and distillation. In this study, wheat straw was explored as feedstock for on-site cellulase production by T. reesei 3EMS35 mutant, and as a substrate for second generation bioethanol production from baker yeast. Scanning electron microscopy (SEM) and X-ray diffractography (XRD) of untreated wheat straw (UWS) and acid treated wheat straw (TWS) were done to understand the structural organization and changes in the cellulase accessibility and reactivity. The effect of delignification and structural modification for on-site cellulase enzyme production was comparably studied. The efficiency of crude cellulase enzyme for digestion of UWS and TWS and then production of ethanol from TWS was studied using same-vessel saccharification and fermentation (SVSF) technique, both in shaking flasks as well as in fermenters. Two different methods of operation were tested, i.e. the UWSEnz method, where UWS was used for on-site enzyme production, and TWSEnz method where TWS was applied as substrate for cellullase production. Results obtained showed structural modifications in cellulose of TWS due to delignification, removal of wax and change of crystallinity. UWS was better substrate than TWS for cellulase production due to the fact that lignin did not hinder the enzyme production by fungus but acted as a booster. On-site cellulase enzyme produced by T. reesei 3EMS35 mutant hydrolyzed most of cellulose (91 %) in TWS within first 24 hrs. Shake flasks experiments showed that ethanol titers and yields with UWSEnz were 2.9 times higher compared to those obtained with TWSEnz method respectively. Comparatively, titer of ethanol in shake flask experiments was 10 % higher than this obtained in 3 L fermenter with UWSEnz. Outcomes from this investigation clearly demonstrated the potential of on-site cellulase enzyme production and SVSF for ethanol production

  8. On-site cellulase production by Trichoderma reesei 3EMS35 mutant and same vessel saccharification and fermentation of acid treated wheat straw for ethanol production

    PubMed Central

    Khokhar, Zia-ullah; Syed, Qurat-ul-Ain; Wu, Jing; Athar, Muhammad Amin

    2014-01-01

    Bioethanol production from lignocellulosic raw materials involves process steps like pre-treatment, enzymatic hydrolysis, fermentation and distillation. In this study, wheat straw was explored as feedstock for on-site cellulase production by T. reesei 3EMS35 mutant, and as a substrate for second generation bioethanol production from baker yeast. Scanning electron microscopy (SEM) and X-ray diffractography (XRD) of untreated wheat straw (UWS) and acid treated wheat straw (TWS) were done to understand the structural organization and changes in the cellulase accessibility and reactivity. The effect of delignification and structural modification for on-site cellulase enzyme production was comparably studied. The efficiency of crude cellulase enzyme for digestion of UWS and TWS and then production of ethanol from TWS was studied using same-vessel saccharification and fermentation (SVSF) technique, both in shaking flasks as well as in fermenters. Two different methods of operation were tested, i.e. the UWSEnz method, where UWS was used for on-site enzyme production, and TWSEnz method where TWS was applied as substrate for cellullase production. Results obtained showed structural modifications in cellulose of TWS due to delignification, removal of wax and change of crystallinity. UWS was better substrate than TWS for cellulase production due to the fact that lignin did not hinder the enzyme production by fungus but acted as a booster. On-site cellulase enzyme produced by T. reesei 3EMS35 mutant hydrolyzed most of cellulose (91 %) in TWS within first 24 hrs. Shake flasks experiments showed that ethanol titers and yields with UWSEnz were 2.9 times higher compared to those obtained with TWSEnz method respectively. Comparatively, titer of ethanol in shake flask experiments was 10 % higher than this obtained in 3 L fermenter with UWSEnz. Outcomes from this investigation clearly demonstrated the potential of on-site cellulase enzyme production and SVSF for ethanol production

  9. Probiotic administration modifies the milk fatty acid profile, intestinal morphology, and intestinal fatty acid profile of goats.

    PubMed

    Apás, A L; Arena, M E; Colombo, S; González, S N

    2015-01-01

    The effect of a mixture of potentially probiotic bacteria (MPPB; Lactobacillus reuteri DDL 19, Lactobacillus alimentarius DDL 48, Enterococcus faecium DDE 39, and Bifidobacterium bifidum strains) on the milk fatty acid (FA) profile, with emphasis on cis-9,trans-11 conjugated linoleic acid (CLA) in the middle stage of goat lactation, was determined. In addition, the effects of MPPB feeding on the FA profile in intestinal content and intestinal morphology in weaned goats were analyzed. The probiotic supplement was able to modify FA composition of milk and intestinal content. The unsaturated FA concentrations in milk (g of FA/L of milk) increased from 4.49 to 7.86 for oleic (18:1), from 0.70 to 1.39 for linoleic (18:2), from 0.063 to 0.187 for linolenic (18:3) acid, and from 0.093 to 0.232 for CLA. The atherogenicity index diminished 2-fold after MPPB ingestion. In the intestinal content of the weaned goats, no significant difference in saturated FA concentration compared with the control was observed. However, oleic acid, linolenic acid, CLA, and docosahexaenoic acid concentrations increased by 81, 23, 344, and 74%, respectively, after probiotic consumption. The ruminal production of CLA was increased by the MPPB. However, bacterial strains of MPPB were unable to produce CLA in culture media. By histological techniques, it was observed that the treated group had intestinally more conserved morphological structures than the control group. The results obtained in this study indicate that the MPPB administration in lactating and weaned goats allows for the production of milk with improved concentrations of beneficial compounds, and also produces a protective effect in the goat intestine. The results obtained in this study reinforce the strategy of probiotics application to enhance goat health with the production of milk with higher concentrations of polyunsaturated FA.

  10. Detection of saccharides by reactive desorption electrospray ionization (DESI) using modified phenylboronic acids

    NASA Astrophysics Data System (ADS)

    Zhang, Yun; Chen, Hao

    2010-01-01

    We have reported previously a method for the detection of sugars via in-situ derivatization with phenylboronic acid PhB(OH)2 using reactive desorption electrospray ionization (DESI, Chen et al., Chem. Commun. (2006) 597-599). The present study describes an improved method that employs modified phenylboronic acids including 3-nitrophenylboronic acid and N-methyl-4-pyridineboronic acid iodide. In contrast to using PhB(OH)2, enhanced sensitivity of using 3-nitrophenylboronic acid was observed due to the stabilization of the resulting boronate ester anion by the electron-withdrawing nitro group and the limit of detections (LODs) for glucose in water using 3-nitrophenylbornic acid and phenylboronic acid were determined to be 0.11 mM and 0.40 mM, respectively. In the case of N-methyl-4-pyridineboronic acid iodide, the corresponding LOD is 6.9 [mu]M and the higher sensitivity obtained is attributed to the efficient ionization of both the reactive DESI reagent and reaction product since the precursor acid with a quaternary ammonium group is pre-charged. In this case, additional important features are found: (i) unlike using phenylboronic acid or 3-nitrophenylbornic acid, the experiment, performed in the positive ion mode, is applicable to neutral and acidic saccharide solutions, facilitating the analysis of biological fluids without the need to adjust pH; (ii) simply by changing the spray solvent from water to acetonitrile, the method can be used for direct glucose analyses of both urine and serum samples via online desalting, due to the low solubility of salts of these biofluids in the sprayed organic solvent; (iii) in comparison with other sugar derivatizing reagents such as the Girard's reagent T, the N-methyl-4-pyridineboronic acid iodide shows higher reactivity in the reactive DESI; and (iv) the ions of saccharide DESI reaction products undergo extensive ring or glycosidic bond cleavage upon CID, a feature that might be useful in the structure elucidation of

  11. Functionalized-graphene modified graphite electrode for the selective determination of dopamine in presence of uric acid and ascorbic acid.

    PubMed

    Mallesha, Malledevaru; Manjunatha, Revanasiddappa; Nethravathi, C; Suresh, Gurukar Shivappa; Rajamathi, Michael; Melo, Jose Savio; Venkatesha, Thimmappa Venkatarangaiah

    2011-06-01

    Graphene is chemically synthesized by solvothermal reduction of colloidal dispersions of graphite oxide. Graphite electrode is modified with functionalized-graphene for electrochemical applications. Electrochemical characterization of functionalized-graphene modified graphite electrode (FGGE) is carried out by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). The behavior of FGGE towards ascorbic acid (AA), dopamine (DA) and uric acid (UA) has been investigated by CV, differential pulse voltammetry (DPV) and chronoamperommetry (CA). The FGGE showed excellent catalytic activity towards electrochemical oxidation of AA, DA and UA compared to that of the bare graphite electrode. The electrochemical oxidation signals of AA, DA and UA are well separated into three distinct peaks with peak potential separation of 193mv, 172mv and 264mV between AA-DA, DA-UA and AA-UA respectively in CV studies and the corresponding peak potential separations in DPV mode are 204mv, 141mv and 345mv. The FGGE is successfully used for the simultaneous detection of AA, DA and UA in their ternary mixture and DA in serum and pharmaceutical samples. The excellent electrocatalytic behavior of FGGE may lead to new applications in electrochemical analysis.

  12. Enhanced biocompatibility and antibacterial property of polyurethane materials modified with citric acid and chitosan.

    PubMed

    Liu, Tian-Ming; Wu, Xing-Ze; Qiu, Yun-Ren

    2016-08-01

    Citric acid (CA) and chitosan (CS) were covalently immobilized on polyurethane (PU) materials to improve the biocompatibility and antibacterial property. The polyurethane pre-polymer with isocyanate group was synthesized by one pot method, and then grafted with citric acid, followed by blending with polyethersulfone (PES) to prepare the blend membrane by phase-inversion method so that chitosan can be grafted from the membrane via esterification and acylation reactions eventually. The native and modified membranes were characterized by attenuated total reflectance-Fourier transform infrared spectroscope, X-ray photoelectron spectroscopy, scanning electron microscopy, water contact angle measurement, and tensile strength test. Protein adsorption, platelet adhesion, hemolysis assay, activated partial thromboplastin time, prothrombin time, thrombin time, and adsorption of Ca(2+) were executed to evaluate the blood compatibility of the membranes decorated by CA and CS. Particularly, the antibacterial activities on the modified membranes were evaluated based on a vitro antibacterial test. It could be concluded that the modified membrane had good anticoagulant property and antibacterial property. PMID:27102367

  13. A solid state fungal fermentation-based strategy for the hydrolysis of wheat straw☆

    PubMed Central

    Pensupa, Nattha; Jin, Meng; Kokolski, Matt; Archer, David B.; Du, Chenyu

    2013-01-01

    This paper reports a solid-state fungal fermentation-based pre-treatment strategy to convert wheat straw into a fermentable hydrolysate. Aspergillus niger was firstly cultured on wheat straw for production of cellulolytic enzymes and then the wheat straw was hydrolyzed by the enzyme solution into a fermentable hydrolysate. The optimum moisture content and three wheat straw modification methods were explored to improve cellulase production. At a moisture content of 89.5%, 10.2 ± 0.13 U/g cellulase activity was obtained using dilute acid modified wheat straw. The addition of yeast extract (0.5% w/v) and minerals significantly improved the cellulase production, to 24.0 ± 1.76 U/g. The hydrolysis of the fermented wheat straw using the fungal culture filtrate or commercial cellulase Ctec2 was performed, resulting in 4.34 and 3.13 g/L glucose respectively. It indicated that the fungal filtrate harvested from the fungal fermentation of wheat straw contained a more suitable enzyme mixture than the commercial cellulase. PMID:24121367

  14. [Change in the content of salicylic acid and activities of phenylalanine ammonia-lyase and catalase in wheat seedling roots under the influence of Azospirilium lectins].

    PubMed

    Alen'kina, S A; Trutneva, K A; Nikitina, V E

    2013-01-01

    The time course of changes in the endogenous content of salicylic acid, the ratio between the acid's free and bound forms, and changes in the activities of phenylalanine ammonia-lyase and catalase in wheat seedling roots under the effect of lectins of two strains of the associative nitrogen-fixing bacterium Azospirillum (A. brasilense Sp7 and its mutant defective in lectin activity, A. brasilense Sp7.2.3) is investigated. Differences in plant response to the action of the lectins from these two strains are established. On the basis of the obtained data, a model is proposed for lectin-assisted induction of resistance, according to which the lectin effect on the roots of seedlings results in the accumulation of free salicylic acid, which inhibits catalase activity, ultimately leading to accumulation of hydrogen peroxide and formation of induced resistance. PMID:25518563

  15. [Change in the content of salicylic acid and activities of phenylalanine ammonia-lyase and catalase in wheat seedling roots under the influence of Azospirilium lectins].

    PubMed

    Alen'kina, S A; Trutneva, K A; Nikitina, V E

    2013-01-01

    The time course of changes in the endogenous content of salicylic acid, the ratio between the acid's free and bound forms, and changes in the activities of phenylalanine ammonia-lyase and catalase in wheat seedling roots under the effect of lectins of two strains of the associative nitrogen-fixing bacterium Azospirillum (A. brasilense Sp7 and its mutant defective in lectin activity, A. brasilense Sp7.2.3) is investigated. Differences in plant response to the action of the lectins from these two strains are established. On the basis of the obtained data, a model is proposed for lectin-assisted induction of resistance, according to which the lectin effect on the roots of seedlings results in the accumulation of free salicylic acid, which inhibits catalase activity, ultimately leading to accumulation of hydrogen peroxide and formation of induced resistance.

  16. Adsorption of Acid Red 57 from aqueous solutions onto surfactant-modified sepiolite.

    PubMed

    Ozcan, Adnan; Ozcan, A Safa

    2005-10-17

    The adsorption of Acid Red 57 (AR57) onto surfactant-modified sepiolite was investigated in aqueous solution in a batch system with respect to contact time, pH and temperature. The surface modification of surfactant-modified sepiolite was controlled using the FTIR technique. The pseudo-first-order, pseudo-second-order kinetic models and the intraparticle diffusion model were used to describe the kinetic data and the rate constants were evaluated. The experimental data fitted very well the pseudo-second-order kinetic model and also followed the intraparticle diffusion model up to 90 min, whereas diffusion is not only the rate controlling step. The Langmuir and Freundlich adsorption models were applied to describe the equilibrium isotherms and the isotherm constants were also determined. The Freundlich model agrees with experimental data well. The activation energy, change of free energy, enthalpy and entropy of adsorption were also evaluated for the adsorption of AR57 onto surfactant-modified sepiolite. The results indicate that surfactant-modified sepiolite could be employed as low-cost material for the removal of textile dyes from effluents. PMID:16019142

  17. Polyoxometalate-Graphene Nanocomposite Modified Electrode for Electrocatalytic Detection of Ascorbic Acid

    SciTech Connect

    Zhang, Weiying; Du, Dan; Gunaratne, Don; Colby, Robert; Lin, Yuehe; Laskin, Julia

    2013-11-15

    Phosphomolybdate functionalized graphene nanocomposite (PMo12-GS) has been successfully formed on a glassy carbon electrode (GCE) for the detection of ascorbic acid (AA). The obtained PMo12-GS modified GCE, was characterized by cyclic voltammetry, electrochemical impedance spectroscopy, scanning electron microscopy (SEM) and Fourier transform infrared (FT-IR) spectroscopy and compared with GCE, GS modified GCE, and PMo12 modified GCE. It shows an increased current and a decrease in over-potential of ~210 mV. The amperometric signals are linearly proportional to the AA concentration in a wide concentration range from 1×10-6 M to 8×10-3 M, with a detection limit of 0.5×10-6 M. Finally, the PMo12-GS modified electrode was employed for the determination of the AA level in vitamin C tablets, with recoveries between 96.3 and 100.8 %.

  18. Au nanoparticles/poly(caffeic acid) composite modified glassy carbon electrode for voltammetric determination of acetaminophen.

    PubMed

    Li, Tianbao; Xu, Juan; Zhao, Lei; Shen, Shaofei; Yuan, Maosen; Liu, Wenming; Tu, Qin; Yu, Ruijin; Wang, Jinyi

    2016-10-01

    An Au nanoparticles/poly(caffeic acid) (AuNPs/PCA) composite modified glassy carbon (GC) electrode was prepared by successively potentiostatic technique in pH 7.4 phosphate buffer solution containing 0.02mM caffeic acid and 1.0mM HAuCl4. Electrochemical characterization of the AuNPs/PCA-GC electrode was investigated by electrochemical impedance spectroscopy and cyclic voltammetry. The electrochemical behavior of acetaminophen (AP) at the AuNPs/PCA-GC electrode was also studied by cyclic voltammetry. Compared with bare GC and poly(caffeic acid) modified GC electrode, the AuNPs/PCA-GC electrode was exhibited excellent electrocatalytic activity toward the oxidation of AP. The plot of catalytic current versus AP concentration showed two linear segments in the concentration ranges 0.2-20µM and 50-1000µM. The detection limit of 14 nM was obtained by using the first range of the calibration plot. The AuNPs/PCA-GC electrode has been successfully applied and validated by analyzing AP in blood, urine and pharmaceutical samples. PMID:27474318

  19. Au nanoparticles/poly(caffeic acid) composite modified glassy carbon electrode for voltammetric determination of acetaminophen.

    PubMed

    Li, Tianbao; Xu, Juan; Zhao, Lei; Shen, Shaofei; Yuan, Maosen; Liu, Wenming; Tu, Qin; Yu, Ruijin; Wang, Jinyi

    2016-10-01

    An Au nanoparticles/poly(caffeic acid) (AuNPs/PCA) composite modified glassy carbon (GC) electrode was prepared by successively potentiostatic technique in pH 7.4 phosphate buffer solution containing 0.02mM caffeic acid and 1.0mM HAuCl4. Electrochemical characterization of the AuNPs/PCA-GC electrode was investigated by electrochemical impedance spectroscopy and cyclic voltammetry. The electrochemical behavior of acetaminophen (AP) at the AuNPs/PCA-GC electrode was also studied by cyclic voltammetry. Compared with bare GC and poly(caffeic acid) modified GC electrode, the AuNPs/PCA-GC electrode was exhibited excellent electrocatalytic activity toward the oxidation of AP. The plot of catalytic current versus AP concentration showed two linear segments in the concentration ranges 0.2-20µM and 50-1000µM. The detection limit of 14 nM was obtained by using the first range of the calibration plot. The AuNPs/PCA-GC electrode has been successfully applied and validated by analyzing AP in blood, urine and pharmaceutical samples.

  20. Hyaluronic Acid Modified Hollow Prussian Blue Nanoparticles Loading 10-hydroxycamptothecin for Targeting Thermochemotherapy of Cancer.

    PubMed

    Jing, Lijia; Shao, Shangmin; Wang, Yang; Yang, Yongbo; Yue, Xiuli; Dai, Zhifei

    2016-01-01

    This paper reported the fabrication of a multifunctional nanoplatform by modifying hollow Prussian blue nanoparticles with hyaluronic acid grafting polyethylene glycol, followed by loading 10-hydroxycamptothecin for tumor-targeted thermochemotherapy. It was found that the surface modification of hollow Prussian blue nanoparticles with hyaluronic acid grafting polyethylene endowed a great colloidal stability, long blood circulation time and the capability for targeting Hela cells over-expressing the CD44 receptor. The obtained nanoagent exhibited efficient photothermal effect and a light triggered and stepwise release behavior of 10-hydroxycamptothecin due to the strong optical absorption in the near-infrared region. The investigations on the body weight change, histological injury and blood biochemical indexes showed that such nanoagent had excellent biocompatibility for medical application. Both in vitro and in vivo experiments proved that the combination of chemotherapy and photothermal therapy through the agent of hyaluronic acid modified Prussian blue nanoparticles loading 10-hydroxycamptothecin could significantly improve the therapeutic efficacy compared with either therapy alone because of a good synergetic effect.

  1. Hyaluronic Acid Modified Hollow Prussian Blue Nanoparticles Loading 10-hydroxycamptothecin for Targeting Thermochemotherapy of Cancer

    PubMed Central

    Jing, Lijia; shao, shangmin; Wang, Yang; Yang, Yongbo; Yue, Xiuli; Dai, Zhifei

    2016-01-01

    This paper reported the fabrication of a multifunctional nanoplatform by modifying hollow Prussian blue nanoparticles with hyaluronic acid grafting polyethylene glycol, followed by loading 10-hydroxycamptothecin for tumor-targeted thermochemotherapy. It was found that the surface modification of hollow Prussian blue nanoparticles with hyaluronic acid grafting polyethylene endowed a great colloidal stability, long blood circulation time and the capability for targeting Hela cells over-expressing the CD44 receptor. The obtained nanoagent exhibited efficient photothermal effect and a light triggered and stepwise release behavior of 10-hydroxycamptothecin due to the strong optical absorption in the near-infrared region. The investigations on the body weight change, histological injury and blood biochemical indexes showed that such nanoagent had excellent biocompatibility for medical application. Both in vitro and in vivo experiments proved that the combination of chemotherapy and photothermal therapy through the agent of hyaluronic acid modified Prussian blue nanoparticles loading 10-hydroxycamptothecin could significantly improve the therapeutic efficacy compared with either therapy alone because of a good synergetic effect. PMID:26722372

  2. Structural resistance of chemically modified 1-D nanostructured titanates in inorganic acid environment

    SciTech Connect

    Marinkovic, Bojan A.; Fredholm, Yann C.; Morgado, Edisson

    2010-10-15

    Sodium containing one-dimensional nanostructured layered titanates (1-D NSLT) were produced both from commercial anatase powder and Brazilian natural rutile mineral sands by alkali hydrothermal process. The 1-D NSLT were chemically modified with proton, cobalt or iron via ionic exchange and all products were additionally submitted to intensive inorganic acid aging (pH = 0.5) for 28 days. The morphology and crystal structure transformations of chemically modified 1-D NSLT were followed by transmission electron microscopy, powder X-ray diffraction, selected area electron diffraction and energy dispersive spectroscopy. It was found that the original sodium rich 1-D NSLT and cobalt substituted 1-D NSLT were completely converted to rutile nanoparticles, while the protonated form was transformed in a 70%-30% (by weight) anatase-rutile nanoparticles mixture, very similar to that of the well-known TiO{sub 2}-photocatalyst P25 (Degussa). The iron substituted 1-D NSLT presented better acid resistance as 13% of the original structure and morphology remained, the rest being converted in rutile. A significant amount of remaining 1-D NSLT was also observed after the acid treatment of the product obtained from rutile sand. The results showed that phase transformation of NSLT into titanium dioxide polymorph in inorganic acid conditions were controllable by varying the exchanged cations. Finally, the possibility to transform, through acid aging, 1-D NSLT obtained from Brazilian natural rutile sand into TiO{sub 2}-polymorphs was demonstrated for the first time to the best of authors' knowledge, opening path for producing TiO{sub 2}-nanoproducts with different morphologies through a simple process and from a low cost precursor.

  3. Separation of modified nucleic acid constituents by micellar electrokinetic capillary chromatography.

    PubMed

    Row, K H; Griest, W H; Maskarinec, M P

    1987-11-13

    Micellar electrokinetic capillary chromatography offers a high-resolution microanalytical technique useful for adducted and modified nucleic acid constituents. A mixture of 14 normal and modified deoxyribonucleosides, deoxyribomononucleotides, a ribonucleoside and a pyrimidine can be resolved in less than 40 min using 10 kV of separating voltage, 0.075 M sodium dodecylsulfate micelles in phosphate-borate buffer, and a 68.5 cm X 60 micron I.D. fused-silica column. Efficiencies up to 370,000 theoretical plates (540,000 plates/m) are achieved, but are highly dependent on solute concentration. The limit of detection for 2'-deoxyguanosine under high-resolution conditions is ca. 18 pg at a signal-to-noise ratio of 4, but the very small injection volumes (ca. 1.5 nl) limit the minimum detectable sample solution concentration to ca. 42 nmol/ml. PMID:3693481

  4. Electrochemical Determination of Glycoalkaloids Using a Carbon Nanotubes-Phenylboronic Acid Modified Glassy Carbon Electrode

    PubMed Central

    Wang, Huiying; Liu, Mingyue; Hu, Xinxi; Li, Mei; Xiong, Xingyao

    2013-01-01

    A versatile strategy for electrochemical determination of glycoalkaloids (GAs) was developed by using a carbon nanotubes-phenylboronic acid (CNTs-PBA) modified glassy carbon electrode. PBA reacts with α-solanine and α-chaconine to form a cyclic ester, which could be utilized to detect GAs. This method allowed GA detection from 1 μM to 28 μM and the detection limit was 0.3 μM. Affinity interaction of GAs and immobilized PBA caused an essential change of the peak current. The CNT-PBA modified electrodes were sensitive for detection of GAs, and the peak current values were in quite good agreement with those measured by the sensors. PMID:24287539

  5. Genetically modified lactic acid bacteria: applications to food or health and risk assessment.

    PubMed

    Renault, Pierre

    2002-11-01

    Lactic acid bacteria have a long history of use in fermented food products. Progress in gene technology allows their modification by introducing new genes or by modifying their metabolic functions. These modifications may lead to improvements in food technology (bacteria better fitted to technological processes, leading to improved organoleptic properties em leader ), or to new applications including bacteria producing therapeutic molecules that could be delivered by mouth. Examples in these two fields will be discussed, at the same time evaluating their potential benefit to society and the possible risks associated with their use. Risk assessment and expected benefits will determine the future use of modified bacteria in the domains of food technology and health.

  6. Characterization of modified calcium-silicate cements exposed to acidic environment

    SciTech Connect

    Camilleri, Josette

    2011-01-15

    Portland cement which is used as a binder in concrete in the construction industry has been developed into a biomaterial. It is marketed as mineral trioxide aggregate and is used in dentistry. This material has been reported to be very biocompatible and thus its use has diversified. The extended use of this material has led to developments of newer versions with improved physical properties. The aim of this study was to evaluate the effect of acidic environments found in the oral cavity on fast setting calcium silicate cements with improved physical properties using a combination of techniques. Two fast setting calcium silicate cements (CSA and CFA) and two cement composites (CSAG and CFAG) were assessed by subjecting the materials to lactic acid/sodium lactate buffer gel for a period of 28 days. At weekly intervals the materials were viewed under the tandem scanning confocal microscope (TSM), and scanning electron microscope (SEM). The two prototype cements exhibited changes in their internal chemistry with no changes in surface characteristics. Since the changes observed were mostly sub-surface evaluation of surface characteristics of cement may not be sufficient in the determination of chemical changes occurring. - Research Highlights: {yields} An acidic environment affects modified fast setting calcium silicate-based cements. {yields} No surface changes are observed in acidic environment. {yields} An acidic environment causes sub-surface changes in the material chemistry which are only visible in fractured specimens. {yields} A combination of techniques is necessary in order to evaluate the chemical changes occurring.

  7. Forced swimming and imipramine modify plasma and brain amino acid concentrations in mice.

    PubMed

    Murakami, Tatsuro; Yamane, Haruka; Tomonaga, Shozo; Furuse, Mitsuhiro

    2009-01-01

    The relationships between monoamine metabolism and forced swimming or antidepressants have been well studied, however information is lacking regarding amino acid metabolism under these conditions. Therefore, the aim of the present study was to investigate the effects of forced swimming and imipramine on amino acid concentrations in plasma, the cerebral cortex and the hypothalamus in mice. Forced swimming caused cerebral cortex concentrations of L-glutamine, L-alanine, and taurine to be increased, while imipramine treatment caused decreased concentrations of L-glutamate, L-alanine, L-tyrosine, L-methionine, and L-ornithine. In the hypothalamus, forced swimming decreased the concentration of L-serine while imipramine treatment caused increased concentration of beta-alanine. Forced swimming caused increased plasma concentration of taurine, while concentrations of L-serine, L-asparagine, L-glutamine and beta-alanine were decreased. Imipramine treatment caused increased plasma concentration of all amino acid, except for L-aspartate and taurine. In conclusion, forced swimming and imipramine treatment modify central and peripheral amino acid metabolism. These results may aid in the identification of amino acids that have antidepressant-like effects, or may help to refine the dosages of antidepressant drugs. PMID:19010319

  8. Isolation and purification of a modified phenazine, griseoluteic acid, produced by Streptomyces griseoluteus P510.

    PubMed

    Wang, Ying; Luo, Qin; Zhang, Xuehong; Wang, Wei

    2011-04-01

    Antibiotic phenazine derivatives and their formation pathways were studied in a new Streptomyces strain P510. Culture characteristics and 16S rRNA nucleotide analysis confirmed strain P510 as Streptomyces griseoluteus. The culture medium of this strain showed strong antimicrobial and antifungal activities. Using organic solvent extraction, silica gel column chromatography and HPLC, a modified phenazine, griseoluteic acid, and a shikimic acid-derived metabolite, p-hydroxybenzaldehyde, were separated and purified. In addition, the biological activity of griseoluteic acid (GA), an important intermediate for biosynthesis of phenazine derivatives, was also investigated in this research. It significantly inhibited growth of Bacillus subtilis. The presence of GA and p-hydroxybenzaldehyde implied that the phenazine biosynthesis pathway in S. griseoluteus P510 might be initiated with shikimic acid, using phenazine-1, 6-dicarboxylic acid as the precursor. The discovery of a partial analogical sequence of phenazine biosynthetic genes, sgpC, sgpD and sgpE, in S. griseoluteus P510 further supported this hypothesis.

  9. The immune modifying effects of amino acids on gut-associated lymphoid tissue

    PubMed Central

    2013-01-01

    The intestine and the gut-associated lymphoid tissue (GALT) are essential components of whole body immune defense, protecting the body from foreign antigens and pathogens, while allowing tolerance to commensal bacteria and dietary antigens. The requirement for protein to support the immune system is well established. Less is known regarding the immune modifying properties of individual amino acids, particularly on the GALT. Both oral and parenteral feeding studies have established convincing evidence that not only the total protein intake, but the availability of specific dietary amino acids (in particular glutamine, glutamate, and arginine, and perhaps methionine, cysteine and threonine) are essential to optimizing the immune functions of the intestine and the proximal resident immune cells. These amino acids each have unique properties that include, maintaining the integrity, growth and function of the intestine, as well as normalizing inflammatory cytokine secretion and improving T-lymphocyte numbers, specific T cell functions, and the secretion of IgA by lamina propria cells. Our understanding of this area has come from studies that have supplemented single amino acids to a mixed protein diet and measuring the effect on specific immune parameters. Future studies should be designed using amino acid mixtures that target a number of specific functions of GALT in order to optimize immune function in domestic animals and humans during critical periods of development and various disease states. PMID:23899038

  10. Reduction of polyester resin shrinkage by means of epoxy resin—I. Epoxy resin modified with acids

    NASA Astrophysics Data System (ADS)

    Pietrzak, M.; Brzostowski, A.

    An attempt was made to decrease the shrinkage of unsaturated polyester resin, taking place during radiation-induced curing, by the addition of epoxy resin. In order to combine chemically both resins, the epoxy component was modified with cinnamic and acrylic acids. A composition of 90 parts of polyesster resin, 10 parts of epoxy resin modified with cinnamic acid, and 150 parts of a silica filler showed a volume shrinkage of 1.2%.

  11. Functionalized graphene with polymer toughener as novel interface modifier for property-tailored poly(lactic acid)/graphene nanocomposites

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In this work, an effective strategy for engineering the interfacial compatibility between graphene and polylactic acid (PLA) was developed by manipulating the functionalization of graphene and introducing an epoxy-containing elastomer modifier. Curing between the functional groups of the modified gr...

  12. Hydroxyapatite formation on graphene oxide modified with amino acids: arginine versus glutamic acid.

    PubMed

    Tavafoghi, M; Brodusch, N; Gauvin, R; Cerruti, M

    2016-01-01

    Hydroxyapatite (HA, Ca5(PO4)3OH) is the main inorganic component of hard tissues, such as bone and dentine. HA nucleation involves a set of negatively charged phosphorylated proteins known as non-collagenous proteins (NCPs). These proteins attract Ca(2+) and PO4(3-) ions and increase the local supersaturation to a level required for HA precipitation. Polar and charged amino acids (AAs) are highly expressed in NCPs, and seem to be responsible for the mineralizing effect of NCPs; however, the individual effect of these AAs on HA mineralization is still unclear. In this work, we investigate the effect of a negatively charged (Glu) and positively charged (Arg) AA bound to carboxylated graphene oxide (CGO) on HA mineralization in simulated body fluids (SBF). Our results show that Arg induces HA precipitation faster and in larger amounts than Glu. We attribute this to the higher stability of the complexes formed between Arg and Ca(2+) and PO4(3-) ions, and also to the fact that Arg exposes both carboxyl and amino groups on the surface. These can electrostatically attract both Ca(2+) and PO4(3-) ions, thus increasing local supersaturation more than Glu, which exposes carboxyl groups only.

  13. Delivery of siRNA Using Cationic Liposomes Incorporating Stearic Acid-modified Octa-Arginine.

    PubMed

    Yang, Dongsheng; Li, Yuhuan; Qi, Yuhang; Chen, Yongzhen; Yang, Xuewei; Li, Yujing; Liu, Songcai; Lee, Robert J

    2016-07-01

    Cationic liposomes incorporating stearic acid-modified octa-arginine (StA-R8) were evaluated for survivin small interfering RNA (siRNA) delivery. StA-R8 was synthesized and incorporated into liposomes. The composition of liposomes was optimized. Physicochemical properties, cytotoxicity, cellular uptake and gene silencing activity of the liposomes complexed to survivin siRNA were investigated. The results showed that StA-R8-containing liposomes had reduced cytotoxicity and improved delivery efficiency of siRNA into cancer cells compared with StA-R8 by itself.

  14. Amine-modified hyaluronic acid-functionalized porous silicon nanoparticles for targeting breast cancer tumors

    NASA Astrophysics Data System (ADS)

    Almeida, Patrick V.; Shahbazi, Mohammad-Ali; Mäkilä, Ermei; Kaasalainen, Martti; Salonen, Jarno; Hirvonen, Jouni; Santos, Hélder A.

    2014-08-01

    Active targeting of nanoparticles to receptor-overexpressing cancer cells has great potential for enhancing the cellular uptake of nanoparticles and for reducing fast clearance of the nanoparticles from the body. Herein, we present a preparation method of a porous silicon (PSi)-based nanodelivery system for breast cancer targeting, by covalently conjugating a synthesized amide-modified hyaluronic acid (HA+) derived polymer on the surface of undecylenic acid-modified thermally hydrocarbonized PSi (UnTHCPSi) nanoparticles. The resulting UnTHCPSi-HA+ nanoparticles showed relatively small size, reduced polydispersibility, high biocompatibility, improved colloidal and human plasma stability, as well as enhanced cellular interactions and internalization. Moreover, we demonstrated that the enhanced cellular association of UnTHCPSi-HA+ relies on the capability of the conjugated HA+ to bind and consequently target CD44 receptors expressed on the surface of breast cancer cells, thus making the HA+-functionalized UnTHCPSi nanoparticles a suitable and promising nanoplatform for the targeting of CD44-overexpressing breast tumors and for drug delivery.Active targeting of nanoparticles to receptor-overexpressing cancer cells has great potential for enhancing the cellular uptake of nanoparticles and for reducing fast clearance of the nanoparticles from the body. Herein, we present a preparation method of a porous silicon (PSi)-based nanodelivery system for breast cancer targeting, by covalently conjugating a synthesized amide-modified hyaluronic acid (HA+) derived polymer on the surface of undecylenic acid-modified thermally hydrocarbonized PSi (UnTHCPSi) nanoparticles. The resulting UnTHCPSi-HA+ nanoparticles showed relatively small size, reduced polydispersibility, high biocompatibility, improved colloidal and human plasma stability, as well as enhanced cellular interactions and internalization. Moreover, we demonstrated that the enhanced cellular association of Un

  15. Delivery of siRNA Using Cationic Liposomes Incorporating Stearic Acid-modified Octa-Arginine.

    PubMed

    Yang, Dongsheng; Li, Yuhuan; Qi, Yuhang; Chen, Yongzhen; Yang, Xuewei; Li, Yujing; Liu, Songcai; Lee, Robert J

    2016-07-01

    Cationic liposomes incorporating stearic acid-modified octa-arginine (StA-R8) were evaluated for survivin small interfering RNA (siRNA) delivery. StA-R8 was synthesized and incorporated into liposomes. The composition of liposomes was optimized. Physicochemical properties, cytotoxicity, cellular uptake and gene silencing activity of the liposomes complexed to survivin siRNA were investigated. The results showed that StA-R8-containing liposomes had reduced cytotoxicity and improved delivery efficiency of siRNA into cancer cells compared with StA-R8 by itself. PMID:27354583

  16. IR spectroscopic study of the surface of TiO/sub 2/ anatase modified with sulfuric acid

    SciTech Connect

    Khadzhiivanov, K.I.; Davydov, A.A.

    1988-10-01

    The elevated activity of anatase modified with sulfuric acid, which is determined by the acidity of the catalyst, has been observed in reactions of acylation, esterification, and isomerization of cyclopropane. It was shown that the formation of surface sulfates in modification of anatase with sulfuric acid causes the appearance of Broensted acid centers which persist up to high dehydration temperatures and an increase in the strength of Lewis acid centers. The symmetry, structure, and sites of the surface sulfates were discussed. The Broensted acid centers are caused by mobile protons bound with sulfate ions.

  17. Voltammetric determination of 6-thioguanine and folic acid using a carbon paste electrode modified with ZnO-CuO nanoplates and modifier.

    PubMed

    Beitollahi, Hadi; Ivari, Susan Ghofrani; Torkzadeh-Mahani, Masoud

    2016-12-01

    ZnO-CuO nanoplates and 2-chlorobenzoyl ferrocene, were synthesized and used to construct a modified carbon paste electrode. The electrooxidation of 6-thioguanine at the surface of the modified electrode was studied. Under the optimized conditions, the square wave voltammetric (SWV) peak current of 6-thioguanine increased linearly in the concentration range 0.05 to 200.0μM and detection limit of 25±2nM was obtained for 6-thioguanine. The prepared modified electrode exhibits a very good resolution between the voltammetric peaks of 6-thioguanine and folic acid which makes it suitable for the detection of 6-thioguanine in the presence of folic acid in real samples. PMID:27612697

  18. Characterizing Nitrous Oxide (N2O) Emissions over a Wheat-based Cropping System in the Northwest United States Using the Modified Bowen Ratio Technique and Static Chambers

    NASA Astrophysics Data System (ADS)

    Waldo, Sarah; Kostyanovsky, Kirill; O'Keeffe, Patrick; Pressley, Shelley; Huggins, Dave; Stockle, Claudio; Lamb, Brian

    2015-04-01

    Nitrous oxide (N2O) is a potent greenhouse gas and ozone depleting substance. Agricultural soils are the primary source of N2O, which is created as a by-product of soil microbial processes. The production and emission of N2O is characterized by high spatial and temporal variability, or "hot spots" and "hot moments". These behaviors, along with limitations in instrument sensitivity to N2O, are challenges in characterizing emissions. Many studies have monitored N2O emissions using either static chambers or micrometeorological measurements or the two methods together. The two techniques are complementary: chamber methods have a lower detection limit and are more reliable as their operation does not depend on atmospheric conditions, but may not capture spatial variability even with multiple chambers. Tower-based methods are subject to relatively high data loss due to non-ideal conditions and to less sensitive detection limits, but have a larger measurement footprint and can characterize field-scale emissions. This study aims to characterize a long-term, field-scale N2O budget over two winter wheat fields located in the Inland Pacific Northwest of the United States, both in terms of an annual emission budget and in terms of understanding what causes hot moments. We combined continuous measurements of N2O emissions from a system of sixteen automated, static chambers with tower-based measurements of N2O fluxes. We used the modified Bowen ratio (MBR) technique with temperature as a tracer. Preliminary results indicate that freeze-thaw cycles in the winter make up a higher percentage of annual emissions than previously thought. Furthermore, comparison of the chamber results to the tower-based measurements imply that the chambers may be underestimating field-scale N2O fluxes because they are not adequately capturing hot spots of emissions. We are conducting ongoing work on how to integrate the two measurement techniques, as well as how the empirical measurements compare with

  19. Characterisation and expression of fatty acid modifying enzyme produced by Staphylococcus epidermidis.

    PubMed

    Chamberlain, N R; Brueggemann, S A

    1997-08-01

    The production of fatty-acid modifying enzyme (FAME) - first identified as a possible virulence factor in Staphylococcus aureus - has also been identified in S. epidermidis. This extracellular enzyme inactivates bactericidal fatty acids by esterifying them to cholesterol. FAME may provide protection for S. epidermidis by inactivating these lipids present on the skin. Over 88% of 51 randomly collected S. epidermidis isolates produced FAME; 92.2% and 13.7% of the same strains produced lipase and slime, respectively. There appeared to be no correlation of lipase activity or slime production with FAME production. The temperature optimum for FAME was between 20 degrees C and 35 degrees C, and the pH optimum was 6.0. Optimal enzyme activity was present at NaCl concentrations of between 250 and 500 mM. FAME was not detected in culture filtrates until early stationary phase, indicating some regulatory control over enzyme production.

  20. [Drug release properties of sodium alginate hydrophobically modified by star polylactic acid].

    PubMed

    Ma, Fu-Wen; Jin, Yong; Zhang, Wen-Fang; Zhou, Shao-Bing; Ni, Cai-Hua

    2010-11-01

    Inorganic/polymer hybrid star polylactic acid (POSS-PLA) was obtained through ring-opening polymerization of lactide by using polyhydroxyl cage silsesquioxane (POSS-OH) as the core and tin (II) octoate as the catalyst. The star polylactic acid (POSS-PLA) was used to modify sodium alginate hydrophobically and a drug carrier was obtained. The drug release behavior was investigated by using ibuprofen as the model drug. The results showed that the drug loading rate could be improved and the release rate was postponed with an increase of POSS-PLA content in the carries. The release mechanism gradually changed from the first-order to the zero-order pattern after the modification.

  1. Citric acid modified kenaf core fibres for removal of methylene blue from aqueous solution.

    PubMed

    Sajab, Mohd Shaiful; Chia, Chin Hua; Zakaria, Sarani; Jani, Saad Mohd; Ayob, Mohd Khan; Chee, Kah Leong; Khiew, Poi Sim; Chiu, Wee Siong

    2011-08-01

    Chemically modified kenaf core fibres were prepared via esterification in the presence of citric acid (CA). The adsorption kinetics and isotherm studies were carried out under different conditions to examine the adsorption efficiency of CA-treated kenaf core fibres towards methylene blue (MB). The adsorption capacity of the kenaf core fibres increased significantly after the citric acid treatment. The values of the correlation coefficients indicated that the Langmuir isotherm fitted the experimental data better than the Freundlich isotherm. The maximum adsorption capacity of the CA-treated kenaf core fibres was found to be 131.6mg/g at 60°C. Kinetic models, pseudo-first-order, pseudo-second-order and intraparticle diffusion, were employed to describe the adsorption mechanism. The kinetic data were found to fit pseudo-second-order model equation as compared to pseudo-first-order model. The adsorption of MB onto the CA-treated kenaf core fibres was spontaneous and endothermic.

  2. The citric acid-modified, enzyme-resistant dextrin from potato starch as a potential prebiotic.

    PubMed

    Sliżewska, Katarzyna

    2013-01-01

    In the present study, enzyme-resistant dextrin, prepared by heating of potato starch in the presence of hydrochloric (0.1% dsb) and citric (0.1% dsb) acid at 130ºC for 3 h (CA-dextrin), was tested as a source of carbon for probiotic lactobacilli and bifidobacteria cultured with intestinal bacteria isolated from feces of three healthy 70-year old volunteers. The dynamics of growth of bacterial monocultures in broth containing citric acid (CA)-modified dextrin were estimated. It was also investigated whether lactobacilli and bifidobacteria cultured with intestinal bacteria in the presence of resistant dextrin would be able to dominate the intestinal isolates. Prebiotic fermentation of resistant dextrin was analyzed using prebiotic index (PI). In co-cultures of intestinal and probiotic bacteria, the environment was found to be dominated by the probiotic strains of Bifidobacterium and Lactobacillus, which is a beneficial effect.

  3. Characterisation and expression of fatty acid modifying enzyme produced by Staphylococcus epidermidis.

    PubMed

    Chamberlain, N R; Brueggemann, S A

    1997-08-01

    The production of fatty-acid modifying enzyme (FAME) - first identified as a possible virulence factor in Staphylococcus aureus - has also been identified in S. epidermidis. This extracellular enzyme inactivates bactericidal fatty acids by esterifying them to cholesterol. FAME may provide protection for S. epidermidis by inactivating these lipids present on the skin. Over 88% of 51 randomly collected S. epidermidis isolates produced FAME; 92.2% and 13.7% of the same strains produced lipase and slime, respectively. There appeared to be no correlation of lipase activity or slime production with FAME production. The temperature optimum for FAME was between 20 degrees C and 35 degrees C, and the pH optimum was 6.0. Optimal enzyme activity was present at NaCl concentrations of between 250 and 500 mM. FAME was not detected in culture filtrates until early stationary phase, indicating some regulatory control over enzyme production. PMID:9511818

  4. Pretreating wheat straw by the concentrated phosphoric acid plus hydrogen peroxide (PHP): Investigations on pretreatment conditions and structure changes.

    PubMed

    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.

  5. Pretreating wheat straw by the concentrated phosphoric acid plus hydrogen peroxide (PHP): Investigations on pretreatment conditions and structure changes.

    PubMed

    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. PMID:26264398

  6. Characterization of fatty acid modifying enzyme activity in staphylococcal mastitis isolates and other bacteria

    PubMed Central

    2012-01-01

    Background Fatty acid modifying enzyme (FAME) has been shown to modify free fatty acids to alleviate their bactericidal effect by esterifying fatty acids to cholesterol or alcohols. Although it has been shown in previous studies that FAME is required for Staphylococcus aureus survival in skin abscesses, FAME is poorly studied compared to other virulence factors. FAME activity had also been detected in coagulase-negative staphylococci (CNS). However, FAME activity was only surveyed after a bacterial culture was grown for 24 h. Therefore if FAME activity was earlier in the growth phase, it would not have been detected by the assay and those strains would have been labeled as FAME negative. Results Fifty CNS bovine mastitis isolates and several S. aureus, Escherichia coli, and Streptococcus uberis strains were assayed for FAME activity over 24 h. FAME activity was detected in 54% of CNS and 80% S. aureus strains surveyed but none in E. coli or S. uberis. While some CNS strains produced FAME activity comparable to the lab strain of S. aureus, the pattern of FAME activity varied among strains and across species of staphylococci. All CNS that produced FAME activity also exhibited lipase activity. Lipase activity relative to colony forming units of these CNS decreased over the 24 h growth period. No relationship was observed between somatic cell count in the milk and FAME activity in CNS. Conclusions Some staphylococcal species surveyed produced FAME activity, but E. coli and S. uberis strains did not. All FAME producing CNS exhibited lipase activity which may indicate that both these enzymes work in concert to alter fatty acids in the bacterial environment. PMID:22726316

  7. Common and distinct gene expression patterns induced by the herbicides 2,4-dichlorophenoxyacetic acid, cinidon-ethyl and tribenuron-methyl in wheat.

    PubMed

    Pasquer, Frédérique; Ochsner, Urs; Zarn, Jürg; Keller, Beat

    2006-12-01

    In wheat, herbicides are used to control weeds. Little is known about the changes induced in the metabolism of tolerant plants after herbicide treatment. The impact of three herbicides [2,4-dichlorophenoxyacetic acid (2,4-D), cinidon-ethyl and tribenuron-methyl] on the wheat transcriptome was studied using cDNA microarrays. Gene expression of plants grown in a controlled environment or in the field was studied between 24 h and 2 weeks after treatment. Under controlled conditions, 2,4-D induced genes of the phenylpropanoid pathway soon after treatment. Cinidon-ethyl triggered peroxidase and defence-related gene expression under controlled conditions, probably because reactive oxygen species are released by photo-oxidation of protoporphyrin-IX. The same genes were upregulated in the field as under controlled conditions, albeit at a weaker level. These results show that cinidon-ethyl specifically induces genes involved in plant defence. Under controlled conditions, tribenuron-methyl did not change the expression profile immediately after treatment, but defence-related genes were upregulated after 1 week. Sulfonylurea compounds such as tribenuron-methyl specifically inhibit acetolactate synthase and are rapidly detoxified, but the activity of some of the resulting metabolites could explain later changes in gene expression. Finally, overexpression of the isopropylmalate synthase gene, involved in branched-chain amino acid synthesis, and of defence-related genes was observed in the field after sulfonylurea treatment. PMID:17054088

  8. K+ and Ca2+ modified Na-X zeolites as possible bile acids sequestrant.

    PubMed

    Linares, Carlos F; Valenzuela, Elymar; Ocanto, Freddy; Pérez, Víctor; Valbuena, Oscar; Goldwasser, Mireya R

    2008-05-01

    Modified zeolite X, previously exchanged with K+ and Ca2+ cations were characterized by XRD, FT-IR, chemical analysis and BET techniques. Different masses of these solids were mixed with an ox bile solution at different reaction times. The supernatants obtained by centrifugations were submitted to bile acid and phospholipids quantitative determinations. The amount of bile acids adsorbed was 65, 28 and 77% and for phospholipids was 45, 67 and 98% for KX, NaX and CaX respectively. As expected, as the amount of mass used increases more bile acids and phospholipids are adsorbed due to a larger surface of the solid being available for adsorption. On the other hand, 120 min of reaction time were sufficient for the adsorption of both components. The solids, after incubations with bile solutions were treated with abundant distilled water and dried at room temperature. The FT-IR analysis of these solids did not detect any bile and on the zeolite surface with suggested that the bile acid adsorption on the exchanged zeolites is moderated by weak and non covalent interactions.

  9. [Absorption of Uranium with Tea Oil Tree Sawdust Modified by Succinic Acid].

    PubMed

    Zhang, Xiao-feng; Chen, Di-yun; Peng, Yan; Liu, Yong-sheng; Xiong, Xue-ying

    2015-05-01

    In order to explore how the modification of succinic acid improves the adsorption of tea oil tree sawdust for uranium, the tea oil tree sawdust was modified by succinic acid, after the pretreatments of crushing, screening, alkalization and acidification. Infrared analysis indicated carboxylic acid groups and ester groups were added to the sawdust after modification, and scanning electron microscope demonstrated after modification the appearance of tea oil tree sawdust was transferred from the structure like compact and straight stripped into the structure like loose and wrinkled leaves, which meant modification increased its inner pores. By the static experiments, effects of reaction time between adsorbent and solvent, dosage of adsorbent, temperature, pH value and initial concentration of uranium were investigated. The results showed that after the modification by succinic acid, the absorption rate of tea oil tree sawdust for uranium increased significantly by about 20% in 12.5 mg · L(-1) initial concentration uranium solution. Adsorption equilibrium was achieved within 180 min, and the kinetic data can be well described by the pseudo-second-order kinetic model. The experimental adsorption isotherm followed the Langmuir and Freundlich models. In addition, the maximum adsorption amounts of tea oil tree sawdust after modification calculated from Langmuir equation raised from 21.413 3 to 31.545 7 mg · g(-1) at 35°C and pH 4.0. PMID:26314117

  10. Wheat Newsletter

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This review was written for readers of the Annual Wheat Newsletter, Volume 53. It summarizes activities on wheat research during 2006 at the U.S. Grain Marketing Research Laboratory (USGMRL). The article includes technical abstracts of research accomplishments from the Grain Quality and Structure ...

  11. Eat Wheat!

    ERIC Educational Resources Information Center

    Idaho Wheat Commission, Boise.

    This pamphlet contains puzzles, games, and a recipe designed to teach elementary school pupils about wheat. It includes word games based on the U.S. Department of Agriculture Food Guide Pyramid and on foods made from wheat. The Food Guide Pyramid can be cut out of the pamphlet and assembled as a three-dimensional information source and food guide.…

  12. Synthesis and characterization of mercaptoacetic acid-modified ZnO nanoparticles

    NASA Astrophysics Data System (ADS)

    Song, Rui; Liu, Ying; He, Linghao

    2008-11-01

    Mercaptoacetic acid (MAA)-modified ZnO nanoparticles have been prepared at low temperature by homogeneous precipitation method, using zinc nitrate hexahydrate and hexamethylenetetramine as initial agents. The modified zinc oxide nanorods were characterized using X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy, scanning electron microscopy (SEM), thermogravimetric (TG) analysis and photoluminescence (PL) spectroscopy. The XRD revealed the wurtzite structure of zinc oxide. The growth of ZnO crystals into rod shape was found to be closely related to its hexagonal nature. As indicated from SEM, the morphology of the modified ZnO nanorods changes with various MAA addition times. In addition, the results of TG and FT-IR confirmed the conjugation of MAA with ZnO nanorods, and the amount of carboxyl group in the samples' surface was found to be 0.1943-0.3491 mmol/g through the titration experiment. The PL spectra indicated that the optical properties of ZnO nanorods were changed with the insertion of MAA, and showed a significant improvement in intensity. On the basis of these results, one might expect that the conjugate specific biomolecules on the functional ZnO nanorods are very potential to detect the complementary biomolecules by PL detecting.

  13. Determination of modification degree in BDDE-modified hyaluronic acid hydrogel by SEC/MS.

    PubMed

    Yang, Biao; Guo, Xueping; Zang, Hengchang; Liu, Jianjian

    2015-10-20

    Determination of modification degree in BDDE-modified hyaluronic acid (HA) hydrogel is of particular interest. In this paper, three crosslinking parameters (degree of total modification, t-MOD; degree of cross-link modification, c-MOD; degree of pendent modification, p-MOD) are defined and determined by quantification of the modified fragments in hydrogel digestion by size exclusion chromatography combined with mass spectrometry (SEC-MS). The digestion products of a novel hyaluronidase HAase-B produced by Bacillus sp. A50 are studied and only a few modified fragments are identified by (1)H NMR and MS. As a result, Three HA hydrogels prepared in lab have different t-MOD, c-MOD and p-MOD, but the ratio of c-MOD to p-MOD result in the almost same value of 75%. Hydrogel products from Q-Med have nearly same t-MOD about 0.8% and c-MOD about 0.1%, the ratio of c-MOD to p-MOD is about 13%. Hydrogels from ANTEIS S.A all have much higher t-MOD values, the ratio of c-MOD and p-MOD is about 8%. PMID:26256180

  14. Surface-modified hyaluronic acid hydrogels to capture endothelial progenitor cells.

    PubMed

    Camci-Unal, Gulden; Aubin, Hug; Ahari, Amirhossein Farajzadeh; Bae, Hojae; Nichol, Jason William; Khademhosseini, Ali

    2010-10-21

    A major challenge to the effective treatment of injured cardiovascular tissues is the promotion of endothelialization of damaged tissues and implanted devices. For this reason, there is a need for new biomaterials that promote endothelialization to enhance vascular repair. The goal of this work was to develop antibody-modified polysaccharide-based hydrogels that could selectively capture endothelial progenitor cells (EPCs). We showed that CD34 antibody immobilization on hyaluronic acid (HA) hydrogels provides a suitable surface to capture EPCs. The effect of CD34 antibody immobilization on EPC adhesion was found to be dependent on antibody concentration. The highest level of EPC attachment was found to be 52.2 cells per mm(2) on 1% HA gels modified with 25 μg mL(-1) antibody concentration. Macrophages did not exhibit significant attachment on these modified hydrogel surfaces compared to the EPCs, demonstrating the selectivity of the system. Hydrogels containing only HA, with or without immobilized CD34, did not allow for spreading of EPCs 48 h after cell seeding, even though the cells were adhered to the hydrogel surface. To promote spreading of EPCs, 2% (w/v) gelatin methacrylate (GelMA) containing HA hydrogels were synthesized and shown to improve cell spreading and elongation. This strategy could potentially be useful to enhance the biocompatibility of implants such as artificial heart valves or in other tissue engineering applications where formation of vascular structures is required.

  15. Preparation and characterization of silver loaded montmorillonite modified with sulfur amino acid

    NASA Astrophysics Data System (ADS)

    Li, Tian; Lin, Oulian; Lu, Zhiyuan; He, Liuimei; Wang, Xiaosheng

    2014-06-01

    The Na+ montmorillonite (MMT) was modified with sulfur containing amino acid (L-cystine, L-cysteine or L-methionine) and characterized by energy dispersive spectrometer (EDS), X-ray diffraction (XRD) and Fourier transform infrared spectrum (FT-IR). The results showed the modification was smooth and the surface condition of MMT was changed with sulfur containing groups. Then silver was loaded on the modified MMTs via ion-exchange reaction under microwave irradiation, the spectra of X-ray photoelectron spectroscopy (XPS), EDS and FT-IR confirmed the successful loading of massive silver and the strong interaction between sulfur and silver, the silver loaded L-cystine modified MMT (Ag@AA-MMT-3) with a silver content of 10.93 wt% was the highest of all. Further more, the Ag@AA-MMT-3 was under the irradiation of a UV lamp to turn silver ions to silver nano particles (Ag NPs). The XPS, specific surface area (SSA), transmission electron microscopy (TEM), XRD patterns and UV-vis spectra proved the existence of uniform nano scaled metallic Ag NPs. By contrast, the UV irradiated Ag@AA-MMT-3 (Ag@AA-MMT-UV) showed a much better slow release property than Ag@AA-MMT-3 or Ag@MMT. The Ag@AA-MMT-UV showing a large inhibition zone and high inhibition ratio presented very good antibacterial property.

  16. Separation of macromolecular proteins and removal of humic acid by cellulose acetate modified UF membranes.

    PubMed

    Kanagaraj, P; Nagendran, A; Rana, D; Matsuura, T

    2016-08-01

    Surface modifying macromolecules (SMMs) were synthesized with various polyurethane pre polymers end-capped with different groups and blended into the casting solution of cellulose acetate (CA) to prepare surface modified ultra-filtration (UF) membranes for water filtration applications. The surface modification of the CA membranes was confirmed by the FTIR and static contact angle (SCA) measurements. The membranes so prepared had the typical characteristics of UF membranes as confirmed by scanning electron microscopy (SEM). Membrane properties were studied in terms of membrane compaction, percentage water content (%WC), pure water flux (PWF), membrane hydraulic resistance (Rm), molecular weight cut-off (MWCO), average pore size and porosity. The result showed that PWF, %WC, MWCO and pore size increased whereas the Rm decreased by the addition of SMMs. The significant effect of SMMs on the fouling by humic acid (HA) was also observed. It was found that the cSMM-3 membrane, in which SMM was synthesized with diethylene glycol (DEG) and hydroxyl benzene sulfonate (HBS) was blended, had the highest flux recovery ratio FRR (84.6%), as well as the lowest irreversible fouling (15.4%), confirming their improved antifouling properties. Thus, the SMM modified CA membranes had proven, to play an important role in the water treatment by UF. PMID:27118046

  17. Separation of macromolecular proteins and removal of humic acid by cellulose acetate modified UF membranes.

    PubMed

    Kanagaraj, P; Nagendran, A; Rana, D; Matsuura, T

    2016-08-01

    Surface modifying macromolecules (SMMs) were synthesized with various polyurethane pre polymers end-capped with different groups and blended into the casting solution of cellulose acetate (CA) to prepare surface modified ultra-filtration (UF) membranes for water filtration applications. The surface modification of the CA membranes was confirmed by the FTIR and static contact angle (SCA) measurements. The membranes so prepared had the typical characteristics of UF membranes as confirmed by scanning electron microscopy (SEM). Membrane properties were studied in terms of membrane compaction, percentage water content (%WC), pure water flux (PWF), membrane hydraulic resistance (Rm), molecular weight cut-off (MWCO), average pore size and porosity. The result showed that PWF, %WC, MWCO and pore size increased whereas the Rm decreased by the addition of SMMs. The significant effect of SMMs on the fouling by humic acid (HA) was also observed. It was found that the cSMM-3 membrane, in which SMM was synthesized with diethylene glycol (DEG) and hydroxyl benzene sulfonate (HBS) was blended, had the highest flux recovery ratio FRR (84.6%), as well as the lowest irreversible fouling (15.4%), confirming their improved antifouling properties. Thus, the SMM modified CA membranes had proven, to play an important role in the water treatment by UF.

  18. Determination of modification degree in BDDE-modified hyaluronic acid hydrogel by SEC/MS.

    PubMed

    Yang, Biao; Guo, Xueping; Zang, Hengchang; Liu, Jianjian

    2015-10-20

    Determination of modification degree in BDDE-modified hyaluronic acid (HA) hydrogel is of particular interest. In this paper, three crosslinking parameters (degree of total modification, t-MOD; degree of cross-link modification, c-MOD; degree of pendent modification, p-MOD) are defined and determined by quantification of the modified fragments in hydrogel digestion by size exclusion chromatography combined with mass spectrometry (SEC-MS). The digestion products of a novel hyaluronidase HAase-B produced by Bacillus sp. A50 are studied and only a few modified fragments are identified by (1)H NMR and MS. As a result, Three HA hydrogels prepared in lab have different t-MOD, c-MOD and p-MOD, but the ratio of c-MOD to p-MOD result in the almost same value of 75%. Hydrogel products from Q-Med have nearly same t-MOD about 0.8% and c-MOD about 0.1%, the ratio of c-MOD to p-MOD is about 13%. Hydrogels from ANTEIS S.A all have much higher t-MOD values, the ratio of c-MOD and p-MOD is about 8%.

  19. Neutralizing Aspartate 83 Modifies Substrate Translocation of Excitatory Amino Acid Transporter 3 (EAAT3) Glutamate Transporters*

    PubMed Central

    Hotzy, Jasmin; Machtens, Jan-Philipp; Fahlke, Christoph

    2012-01-01

    Excitatory amino acid transporters (EAATs) terminate glutamatergic synaptic transmission by removing glutamate from the synaptic cleft into neuronal and glial cells. EAATs are not only secondary active glutamate transporters but also function as anion channels. Gating of EAAT anion channels is tightly coupled to transitions within the glutamate uptake cycle, resulting in Na+- and glutamate-dependent anion currents. A point mutation neutralizing a conserved aspartic acid within the intracellular loop close to the end of transmembrane domain 2 was recently shown to modify the substrate dependence of EAAT anion currents. To distinguish whether this mutation affects transitions within the uptake cycle or directly modifies the opening/closing of the anion channel, we used voltage clamp fluorometry. Using three different sites for fluorophore attachment, V120C, M205C, and A430C, we observed time-, voltage-, and substrate-dependent alterations of EAAT3 fluorescence intensities. The voltage and substrate dependence of fluorescence intensities can be described by a 15-state model of the transport cycle in which several states are connected to branching anion channel states. D83A-mediated changes of fluorescence intensities, anion currents, and secondary active transport can be explained by exclusive modifications of substrate translocation rates. In contrast, sole modification of anion channel opening and closing is insufficient to account for all experimental data. We conclude that D83A has direct effects on the glutamate transport cycle and that these effects result in changed anion channel function. PMID:22532568

  20. Controllable Phase Separation by Boc-Modified Lipophilic Acid as a Multifunctional Extractant

    NASA Astrophysics Data System (ADS)

    Tao, Kai; Adler-Abramovich, Lihi; Gazit, Ehud

    2015-12-01

    While phase separation of immiscible liquid-liquid systems has become increasingly significant in diverse areas, the irreversible nature limits their further application in controllable extraction-concentration or capture-release fields. There is a need for the development of simple, efficient and reversible methods for numerous research and industrial extraction and separation applications. We envisioned Boc-modified lipophilic acids as a simple model for such use based on the studies of the multi-phase transitions of Boc-modified supramolecular polymeric systems. Here, we demonstrate that in the presence of Boc-7-aminoheptanoic acid (Boc-7), phase separation occurs in mixtures of miscible organic solvent and water. The separation behavior was confirmed by differential colorimetric development in aqueous and organic phases using methyl orange staining assays. Component substitution experiments verified that the phase separation results from the subtle balance between the aggregation and the solvation forces of Boc-7, and is reversible by adjusting the solution pH. Owing to the intrinsic hydrophobic properties of the organic phase and the hydrogen bonding-forming ability of the carboxyl group of Boc-7, the phase separation system captures and releases Sudan Red, fluorescein, and streptavidin in a controllable manner. Consequently, a reversible and simple phase separation system can be designed as a multifunctional extractant.

  1. Formation of bowl-shaped nanoparticles by self-assembly of cinnamic acid-modified dextran.

    PubMed

    Zhang, Cuige; Yang, Suhan; Zhu, Ye; Zhang, Rongli; Liu, Xiaoya

    2015-11-20

    The self-assembly of amphiphilic copolymers has attracted much attention because of their various morphologies and potential applications. Bowl-shaped nanoparticles could apply in many aspects due to their interior cavity, specific concave structure and high surface area. In this study, dextran (Dex) was hydrophobic modified by cinnamic acid (CINN) via esterification reaction between the hydroxyl group of Dex and the carboxyl group of CINN. The modification degree of CINN could be achieved by changing the feed ratios between Dex, CINN and the coupling agent. The cinnamic acid-modified dextran (Dex-CINN) composed of Dex as hydrophilic segment and CINN as hydrophobic segment could self-assemble into bowl-shaped nanoparticles with a single dimple on the surface. Furthermore, the size of the dimples could be controlled by changing the modification degree of CINN, concentration of Dex-CINN and the rate of water addition. The morphologies of bowl-shaped nanoparticles were characterized by transmission electron microscopy (TEM) and scanning electron microscope (SEM).

  2. Hyaluronic acid-modified multiwalled carbon nanotubes for targeted delivery of doxorubicin into cancer cells.

    PubMed

    Cao, Xueyan; Tao, Lei; Wen, Shihui; Hou, Wenxiu; Shi, Xiangyang

    2015-03-20

    Development of novel drug carriers for targeted cancer therapy with high efficiency and specificity is of paramount importance and has been one of the major topics in current nanomedicine. Here we report a general approach to using multifunctional multiwalled carbon nanotubes (MWCNTs) as a platform to encapsulate an anticancer drug doxorubicin (DOX) for targeted cancer therapy. In this approach, polyethyleneimine (PEI)-modified MWCNTs were covalently conjugated with fluorescein isothiocyanate (FI) and hyaluronic acid (HA). The formed MWCNT/PEI-FI-HA conjugates were characterized via different techniques and were used as a new carrier system to encapsulate the anticancer drug doxorubicin for targeted delivery to cancer cells overexpressing CD44 receptors. We show that the formed MWCNT/PEI-FI-HA/DOX complexes with a drug loading percentage of 72% are water soluble and stable. In vitro release studies show that the drug release rate under an acidic condition (pH 5.8, tumor cell microenvironment) is higher than that under physiological condition (pH 7.4). Cell viability assay demonstrates that the carrier material has good biocompatibility in the tested concentration range, and the MWCNT/PEI-FI-HA/DOX complexes can specifically target cancer cells overexpressing CD44 receptors and exert growth inhibition effect to the cancer cells. The developed HA-modified MWCNTs hold a great promise to be used as an efficient anticancer drug carrier for tumor-targeted chemotherapy.

  3. Amine-modified hyaluronic acid-functionalized porous silicon nanoparticles for targeting breast cancer tumors.

    PubMed

    Almeida, Patrick V; Shahbazi, Mohammad-Ali; Mäkilä, Ermei; Kaasalainen, Martti; Salonen, Jarno; Hirvonen, Jouni; Santos, Hélder A

    2014-09-01

    Active targeting of nanoparticles to receptor-overexpressing cancer cells has great potential for enhancing the cellular uptake of nanoparticles and for reducing fast clearance of the nanoparticles from the body. Herein, we present a preparation method of a porous silicon (PSi)-based nanodelivery system for breast cancer targeting, by covalently conjugating a synthesized amide-modified hyaluronic acid (HA(+)) derived polymer on the surface of undecylenic acid-modified thermally hydrocarbonized PSi (UnTHCPSi) nanoparticles. The resulting UnTHCPSi-HA(+) nanoparticles showed relatively small size, reduced polydispersibility, high biocompatibility, improved colloidal and human plasma stability, as well as enhanced cellular interactions and internalization. Moreover, we demonstrated that the enhanced cellular association of UnTHCPSi-HA(+) relies on the capability of the conjugated HA(+) to bind and consequently target CD44 receptors expressed on the surface of breast cancer cells, thus making the HA(+)-functionalized UnTHCPSi nanoparticles a suitable and promising nanoplatform for the targeting of CD44-overexpressing breast tumors and for drug delivery.

  4. Controllable Phase Separation by Boc-Modified Lipophilic Acid as a Multifunctional Extractant

    PubMed Central

    Tao, Kai; Adler-Abramovich, Lihi; Gazit, Ehud

    2015-01-01

    While phase separation of immiscible liquid-liquid systems has become increasingly significant in diverse areas, the irreversible nature limits their further application in controllable extraction-concentration or capture-release fields. There is a need for the development of simple, efficient and reversible methods for numerous research and industrial extraction and separation applications. We envisioned Boc-modified lipophilic acids as a simple model for such use based on the studies of the multi-phase transitions of Boc-modified supramolecular polymeric systems. Here, we demonstrate that in the presence of Boc-7-aminoheptanoic acid (Boc-7), phase separation occurs in mixtures of miscible organic solvent and water. The separation behavior was confirmed by differential colorimetric development in aqueous and organic phases using methyl orange staining assays. Component substitution experiments verified that the phase separation results from the subtle balance between the aggregation and the solvation forces of Boc-7, and is reversible by adjusting the solution pH. Owing to the intrinsic hydrophobic properties of the organic phase and the hydrogen bonding-forming ability of the carboxyl group of Boc-7, the phase separation system captures and releases Sudan Red, fluorescein, and streptavidin in a controllable manner. Consequently, a reversible and simple phase separation system can be designed as a multifunctional extractant. PMID:26627307

  5. Chemically modified polymeric resins for separation of cations, organic acids, and small polar moleculea by high performance liquid chromatography

    SciTech Connect

    Morris, J.B.

    1993-07-01

    This thesis is divided into 4 parts: a review, ion chromatography of metal cations on carboxylic resins, separation of hydrophilic organic acids and small polar compounds on macroporous resin columns, and use of eluent modifiers for liquid chromatographic separation of carboxylic acids using conductivity detection.

  6. Gold Electrodes Modified with Self-Assembled Monolayers for Measuring L-Ascorbic Acid: An Undergraduate Analytical Chemistry Laboratory Experiment

    ERIC Educational Resources Information Center

    Ito, Takashi; Perera, D. M. Neluni T.; Nagasaka, Shinobu

    2008-01-01

    This article describes an undergraduate electrochemistry laboratory experiment in which the students measure the L-ascorbic acid content of a real sample. Gold electrodes modified with self-assembled monolayers (SAMs) of thioctic acid and cysteamine are prepared to study the effects of surface modification on the electrode reaction of L-ascorbic…

  7. Modified biofunctional p(tannic acid) microgels and their antimicrobial activity

    NASA Astrophysics Data System (ADS)

    Sagbas, Selin; Aktas, Nahit; Sahiner, Nurettin

    2015-11-01

    Crosslinked poly(tannic acid) micro particles, p(TA), were synthesized using trimethylolpropane triglycidyl ether (TMPGDE) as crosslinker in a single step with high yield (73 ± 6%). The obtained p(TA) microgels possessed negative zeta potential, -27 mV, and the surface charge can be tuned by chemical modification using various modifying agents, such as 3-chloro-2-hydroxypropyl ammonium chloride (CHPACl) and chloro sulfonic acid (CSA) to generate microgels with different zeta potentials, e.g., -18 mV and -36 mV, respectively. Modified p(TA) microgels are found to be thermally less stable than bare p(TA) particles. Additionally, upon chemical modification of p(TA) particles, the antioxidant capacity of the p(TA) microgels decreased confirming the utilization of some of the phenolic groups, the main functional groups responsible for the antioxidant property of TA moieties. Moreover, the antimicrobial properties increased approximately four fold against three common bacterial strains; Escherichia coli ATCC 8739, Staphylococcus aureus ATCC 6538, and Bacillus subtilis ATCC 6633. P(TA) microgels as TA molecules have a natural capability to reduce metal ions, allowing in situ reduction of absorbed Ag and Cu ions to the corresponding metal nanoparticles within the p(TA) microgel network. The composite p(TA)-M (M: Ag or Cu) nanoparticle demonstrated superior antimicrobial activity against the mentioned bacteria compared to the bare p(TA) microgels. Moreover, bare and modified p(TA) microgels are shown to be drug carrier materials by loading three model drugs, phenylephrine HCl (PHE), trimethoprim (TMP), and naproxen (NP), and releasing them in phosphate buffer saline PBS (pH 7.4) at 37.5 °C.

  8. Modification of wheat flour with bromelain and baking hypoallergenic bread with added ingredients.

    PubMed

    Tanabe, S; Arai, S; Watanabe, M

    1996-08-01

    Based on the wheat glutenin IgE-binding epitope, Gln-Gln-Gln-Pro-Pro, a practical method is proposed for the production of hypoallergenic wheat flour. Bromelain was found effective for decomposing the epitope structure. In practice, soft flour was mixed with water dissolving bromelain and the mixture was incubated at 37 degrees C for 4 h. The result of IgE-ELISA (enzyme-linked immunosorbent assay) suggested negative allergenicity. A mixture of bromelain-modified flour, glucose, citric, acid, a surfactant and sodium hydrogen carbonate was baked to produce hypoallergenic bread, resembling English muffins.

  9. Application of palladium-catalyzed carboxyl anhydride-boronic acid cross coupling in the synthesis of novel bile acids analogs with modified side chains.

    PubMed

    Mayorquín-Torres, Martha C; Flores-Álamo, Marcos; Iglesias-Arteaga, Martin A

    2015-09-01

    Palladium-catalyzed cross coupling of 4-methoxycarbonyl phenyboronic acid with acetylated bile acids in which the carboxyl functions was activated by formation of a mixed anhydride with pivalic anhydride afforded the cross coupled compounds, which were converted in novel side chain modified bile acids by one pot carbonyl reduction/removal of the protecting acetyl groups by Wolff-Kishner reduction. Unambiguous assignments of the NMR signals and crystal characterization of the heretofore unknown compounds are provided.

  10. Preparative separation of enantiomers based on functional nucleic acids modified gold nanoparticles.

    PubMed

    Huang, Rong; Wang, Daifang; Liu, Shuzhen; Guo, Longhua; Wang, Fangfang; Lin, Zhenyu; Qiu, Bin; Chen, Guonan

    2013-11-01

    The preparative-scale separation of chiral compounds is vitally important for the pharmaceutical industry and related fields. Herein we report a simple approach for rapid preparative separation of enantiomers using functional nucleic acids modified gold nanoparticles (AuNPs). The separation of DL-tryptophan (DL-Trp) is demonstrated as an example to show the feasibility of the approach. AuNPs modified with enantioselective aptamers were added into a racemic mixture of DL -Trp. The aptamer-specific enantiomer (L-Trp) binds to the AuNPs surface through aptamer-L-Trp interaction. The separation of DL-Trp is then simply accomplished by centrifugation: the precipitate containing L-Trp bounded AuNPs is separated from the solution, while the D-Trp remains in the supernatant. The precipitate is then redispersed in water. The aptamer is denatured under 95 °C and a second centrifugation is then performed, resulting in the separation of AuNPs and L-Trp. The supernatant is finally collected to obtain pure L-Trp in water. The results show that the racemic mixture of DL-Trp is completely separated into D-Trp and L-Trp, respectively, after 5 rounds of repeated addition of fresh aptamer-modified AuNPs to the DL-Trp mixture solution. Additionally, the aptamer-modified AuNPs can be repeatedly used for at least eight times without significant loss of its binding ability because the aptamer can be easily denatured and renatured in relatively mild conditions. The proposed approach could be scaled up and extended to the separation of other enantiomers by the adoption of other enantioselective aptamers.

  11. Hypohalous acid-modified human serum albumin induces neutrophil NADPH oxidase activation, degranulation, and shape change.

    PubMed

    Gorudko, Irina V; Grigorieva, Daria V; Shamova, Ekaterina V; Kostevich, Valeria A; Sokolov, Alexey V; Mikhalchik, Elena V; Cherenkevich, Sergey N; Arnhold, Jürgen; Panasenko, Oleg M

    2014-03-01

    Halogenated lipids, proteins, and lipoproteins formed in reactions with myeloperoxidase (MPO)-derived hypochlorous acid (HOCl) and hypobromous acid (HOBr) can contribute to the regulation of functional activity of cells and serve as mediators of inflammation. Human serum albumin (HSA) is the major plasma protein target of hypohalous acids. This study was performed to assess the potency of HSA modified by HOCl (HSA-Cl) and HOBr (HSA-Br) to elicit selected neutrophil responses. HSA-Cl/Br were found to induce neutrophil degranulation, generation of reactive oxygen intermediates, shape change, and actin cytoskeleton reorganization. Thus HSA-Cl/Br can initially act as a switch and then as a feeder of the "inflammatory loop" under oxidative stress. In HSA-Cl/Br-treated neutrophils, monoclonal antibodies against CD18, the β subunit of β2 integrins, reduced the production of superoxide anion radicals and hydrogen peroxide as well as MPO exocytosis, suggesting that CD18 contributed to neutrophil activation. HSA-Cl/Br-induced neutrophil responses were also inhibited by genistein, a broad-specificity tyrosine kinase inhibitor, and wortmannin, a phosphoinositide 3-kinase (PI3K) inhibitor, supporting the notion that activation of both tyrosine kinase and PI3K may play a role in neutrophil activation by HSA modified in MPO-dependent reactions. These results confirm the hypothesis that halogenated molecules formed in vivo via MPO-dependent reactions can be considered as a new class of biologically active substances potentially able to contribute to activation of myeloid cells in sites of inflammation and serve as inflammatory response modulators. PMID:24384524

  12. Effective Trapping of Fruit Flies with Cultures of Metabolically Modified Acetic Acid Bacteria

    PubMed Central

    Ishii, Yuri; Akasaka, Naoki; Goda, Itsuko; Sakoda, Hisao

    2015-01-01

    Acetoin in vinegar is an attractant to fruit flies when combined with acetic acid. To make vinegar more effective in attracting fruit flies with increased acetoin production, Komagataeibacter europaeus KGMA0119 was modified by specific gene disruption of the acetohydroxyacid isomeroreductase gene (ilvC). A previously constructed mutant lacking the putative ligand-sensing region in the leucine-responsive regulatory protein (KeLrp, encoded by Kelrp) was also used. The ilvC and Kelrp disruptants (KGMA5511 and KGMA7203, respectively) produced greater amounts of acetoin (KGMA5511, 0.11%; KGMA7203, 0.13%) than the wild-type strain KGMA0119 (0.069%). KGMA7203 produced a trace amount of isobutyric acid (0.007%), but the other strains did not. These strains produced approximately equal amounts of acetic acid (0.7%). The efficiency of fruit fly attraction was investigated with cultured Drosophila melanogaster. D. melanogaster flies (approximately 1,500) were released inside a cage (2.5 m by 2.5 m by 1.5 m) and were trapped with a device containing vinegar and a sticky sheet. The flies trapped on the sticky sheet were counted. The cell-free supernatant from KGMA7203 culture captured significantly more flies (19.36 to 36.96% of released flies) than did KGMA0119 (3.25 to 11.40%) and KGMA5511 (6.87 to 21.50%) cultures. Contrastingly, a 0.7% acetic acid solution containing acetoin (0.13%) and isobutyric acid (0.007%), which mimicked the KGMA7203 supernatant, captured significantly fewer flies (0.88 to 4.57%). Furthermore, the KGMA0119 supernatant with additional acetoin (0.13%) and isobutyric acid (0.007%) captured slightly more flies than the original KGMA0119 supernatant but fewer than the KGMA7203 supernatant, suggesting that the synergistic effects of acetic acid, acetoin, isobutyric acid, and unidentified metabolites achieved the efficient fly trapping of the KGMA7203 supernatant. PMID:25595769

  13. XPS and wettability characterization of modified poly(lactic acid) and poly(lactic/glycolic acid) films.

    PubMed

    Kiss, E; Bertóti, I; Vargha-Butler, E I

    2002-01-01

    Poly(lactic acid) (PLA) and poly(lactic/glycolic acid) copolymers (PLGA) are biodegradable drug carriers of great importance, although successful pharmaceutical application requires adjustment of the surface properties of the polymeric drug delivery system to be compatible with the biological environment. For that reason, reduction of the original hydrophobicity of the PLA or PLGA surfaces was performed by applying a hydrophilic polymer poly(ethylene oxide) (PEO) with the aim to improve biocompatibility of the original polymer. PEO-containing surfaces were prepared by incorporation of block copolymeric surfactants, poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide) (Pluronic), into the hydrophobic surface. Films of polymer blends from PLA or PLGA (with lactic/glycolic acid ratios of 75/25 and 50/50) and from Pluronics (PE6800, PE6400, and PE6100) were obtained by the solvent casting method, applying the Pluronics at different concentrations between 1 and 9.1% w/w. Wettability was measured to monitor the change in surface hydrophobicity, while X-ray photoelectron spectroscopy (XPS) was applied to determine the composition and chemical structure of the polymer surface and its change with surface modification. Substantial reduction of surface hydrophobicity was achieved on both the PLA homopolymer and the PLGA copolymers by applying the Pluronics at various concentrations. In accordance with the wettability changes the accumulation of Pluronics in the surface layer was greatly affected by the initial hydrophobicity of the polymer, namely, by the lactide content of the copolymer. The extent of surface modification was also found to be dependent on the type of blended Pluronics. Surface activity of the modifying Pluronic component was interpreted by using the solubility parameters. PMID:16290340

  14. Degradation of chloro- and methyl-substituted benzoic acids by a genetically modified microorganism

    SciTech Connect

    Mueller, R.; Deckwer, W.D.; Hecht, V.

    1996-09-05

    Degradation of 3-chlorobenzoic acid (3CB), 4-chlorobenzoic acid (4CB), and 4-methylbenzoic acid (4MB) as single substrates (carbon sources) and as a substrate mixture were studied in batch and continuous culture using the genetically modified microorganism Pseudomonas sp. B13 FR1 SN45P. The strain was able to mineralize the single compounds as well as the substrate mixture completely. Conversion of the three compounds in the substrate mixture proceeded simultaneously. Maximum specific substrate conversion rates were calculated to be 0.9 g g{sup {minus}1} h{sup {minus}1} for 3 CB and 4CB and 1.1 g g{sup {minus}1} h{sup {minus}1} for 4MB. Mass balances indicated the transient accumulation of pathway intermediates during batch cultivations. Hence, the rate limiting step in the degradative pathway is not the initial microbial attack of the original substrate or its transport through the cell membrane. Degradation rates on 3CB were comparable to those of the parent strain Pseudomonas sp. B13. The stability of the degradation pathways of strain Pseudomonas sp. B13 FR1 SN45P could be demonstrated in a continuous cultivation over 3.5 months (734 generation times) on 3CB, 4MB, and 4CB, which were used a single carbon sources one after the other.

  15. Does exogenous application of salicylic acid through the rooting medium modulate growth and photosynthetic capacity in two differently adapted spring wheat cultivars under salt stress?

    PubMed

    Arfan, Muhammad; Athar, Habib R; Ashraf, Muhammad

    2007-06-01

    In order to assess whether exogenous application of salicylic acid (SA) through the rooting medium could modulate the photosynthetic capacity of two wheat cultivars differing in salinity tolerance, a hydroponic experiment was conducted under greenhouse conditions. Seeds of a salt tolerant (S-24) and a moderately salt sensitive (MH-97) cultivar were germinated at 0 or 150 mM NaCl in Hoagland's nutrient solution containing different levels of salicylic acid (SA) (0, 0.25, 0.50, 0.75 and 1.00 mM) for 7d. Seven-day old wheat seedlings were transferred to hydroponics and grown at 0, or 150 mM NaCl for for further 30 d. Different levels of salicylic acid (SA) were also maintained in the solution culture. After 30 d, four plants out of six were harvested and the remaining plants were left for the estimation of yield attributes Salt stress reduced the growth and grain yield of both cultivars. However, cv. S-24 performed better than MH-97 under salt stress with respect to leaf area, and grain yield. Exogenous application of SA promoted growth and yield, and counteracted the salt stress-induced growth inhibition of salt tolerant S-24, whereas for MH-97 there was no improvement in growth or grain yield with SA application. Of the varying SA levels used, the most effective levels for promoting growth and grain yield were 0.75 and 0.25 mM under normal and saline conditions, respectively. The improvement in growth and grain yield of S-24 due to SA application was associated with improved photosynthetic capacity. Changes in photosynthetic rate due to SA application were not due to stomatal limitations, but were associated with metabolic factors, other than photosynthetic pigments and leaf carotenoids.

  16. Transcriptional coordination and abscisic acid mediated regulation of sucrose transport and sucrose-to-starch metabolism related genes during grain filling in wheat (Triticum aestivum L.).

    PubMed

    Mukherjee, Shalini; Liu, Aihua; Deol, Kirandeep K; Kulichikhin, Konstanin; Stasolla, Claudio; Brûlé-Babel, Anita; Ayele, Belay T

    2015-11-01

    Combining physiological, molecular and biochemical approaches, this study investigated the transcriptional coordination and abscisic acid (ABA) mediated regulation of genes involved in sucrose import and its conversion to starch during grain filling in wheat. Sucrose import appears to be mediated by seed localized TaSUT1, mainly TaSUT1D, while sucrose cleavage by TaSuSy2. Temporal overlapping of the transcriptional activation of AGPL1 and AGPS1a that encode AGPase with that of the above genes suggests their significance in the synthesis of ADP-glucose; TaAGPL1A and TaAGPL1D contributing the majority of AGPL1 transcripts. ABA induced repressions of TaSUT1, TaSuSy2, TaAGPL1 and TaAGPS1a imply that ABA negatively regulates sucrose import into the endosperm and its subsequent metabolism to ADP-glucose, the substrate for starch synthesis. The formations of amyloses and amylopectin from ADP-glucose appear to be mediated by specific members of GBSS, and SS, SBE and DBE gene families, and the ABA-induced transcriptional change in most of these genes implies that ABA regulates amylose and amylopectin synthesis. The findings provide insights into the molecular mechanisms underlying the coordination and ABA mediated regulation of sucrose transport into the developing endosperm and its subsequent metabolism to starch during grain filling in wheat.

  17. Novel xylanase from a holstein cattle rumen metagenomic library and its application in xylooligosaccharide and ferulic Acid production from wheat straw.

    PubMed

    Cheng, Fansheng; Sheng, Jiping; Dong, Rubo; Men, Yejun; Gan, Lin; Shen, Lin

    2012-12-26

    A novel gene fragment containing a xylanase was identified from a Holstein cattle rumen metagenomic library. The novel xylanase (Xyln-SH1) belonged to the glycoside hydrolase family 10 (GH10) and exhibited a maximum of 44% identity to the glycoside hydrolase from Clostridium thermocellum ATCC 27405. Xyln-SH1 was heterologously expressed, purified, and characterized. A high level of activity was obtained under the optimum conditions of pH 6.5 and 40 °C. A substrate utilization study indicated that Xyln-SH1 was cellulase-free and strictly specific to xylan from softwood. The synergistic effects of Xyln-SH1 and feruloyl esterase (FAE-SH1) were observed for the release of xylooligosaccharides (XOS) and ferulic acid (FA) from wheat straw. In addition, a high dose of Xyln-SH1 alone was observed to improve the release of FA from wheat straw. These features suggest that this enzyme has substantial potential to improve biomass degradation and industrial applications.

  18. Enhancement of power production with tartaric acid doped polyaniline nanowire network modified anode in microbial fuel cells.

    PubMed

    Liao, Zhi-Hong; Sun, Jian-Zhong; Sun, De-Zhen; Si, Rong-Wei; Yong, Yang-Chun

    2015-09-01

    The feasibility to use tartaric acid doped PANI for MFC anode modification was determined. Uniform PANI nanowires doped with tartaric acid were synthesized and formed mesoporous networks on the carbon cloth surface. By using this tartaric acid doped PANI modified carbon cloth (PANI-TA) as the anode, the voltage output (435 ± 15 mV) and power output (490 ± 12 mW/m(2)) of MFC were enhanced by 1.6 times and 4.1 times compared to that of MFC with plain carbon cloth anode, respectively. Strikingly, the performance of PANI-TA MFC was superior to that of the MFCs with inorganic acids doped PNAI modified anode. These results substantiated that tartaric acid is a promising PANI dopant for MFC anode modification, and provided new opportunity for MFC performance improvement.

  19. Colorimetric Detection of Cadmium Ions Using DL-Mercaptosuccinic Acid-Modified Gold Nanoparticles.

    PubMed

    Chen, Na; Chen, Jun; Yang, Jing-Hua; Bai, Lian-Yang; Zhang, Yu-Ping

    2016-01-01

    A colorimetric assay has been developed for detection of Cd²⁺ utilizing DL-mercaptosuccinic acid-modified gold nanoparticles (MSA-AuNPs). The method showed good selectivity for Cd²⁺ over other metal ions. As a result, the linear relationships (r > 0.9606) between concentration 0.07 mM and 0.20 mM for cadmium ion were obtained. The detection limit was as low as 0.07 mM by the naked eye. The effect of pH on the aggregation was optimized. The MSA-AuNPs probe could be used to detect Cd²⁺ in an aqueous solution based on the aggregation-induced color change of MSA-AuNPs. PMID:27398533

  20. Properties of baked foams from citric acid modified cassava starch and native cassava starch blends.

    PubMed

    Pornsuksomboon, Kanlaya; Holló, Berta Barta; Szécsényi, Katalin Mészáros; Kaewtatip, Kaewta

    2016-01-20

    Starch foams from native cassava starch (NS) and citric acid modified cassava starch (CNS) were prepared using baking processes with blend ratios of 80/20, 60/40, 50/50, 40/60 and 20/80. The density, thickness, morphology, thermal stability and water absorption of the NS, CNS and blended starch foams were determined. The ratio of the two starch components had a significant influence on the density and thickness of the blended starch foams. All blended starch foams showed good water resistance. Moreover, the morphology of the blended starch foam with the NS/CNS ratio of 50/50 showed a more ordered distribution of cell sizes with thicker cell walls than for the NS and CNS foams. The thermal stability of the blended starch foams was somewhat lower than the stability of the NS foam but not to the extent that it affected any potential practical applications.

  1. Synthesis of ring-C modified oleanolic acid derivatives and their cytotoxic evaluation.

    PubMed

    Pattnaik, Banita; Lakshma Nayak, Vadithe; Ramakrishna, Sistla; Venkata Mallavadhani, Uppuluri

    2016-10-01

    Ring-C of oleanolic acid was chemically modified by treating with NBS under a variety of experimental conditions. The structures of the synthesized compounds were established by spectral analysis ((1)H &(13)C NMR and Mass). All the compounds were evaluated against a panel of five human cancer cell lines by using MTT assay. Among the tested compounds, 2 and 7 showed significant activity against breast cancer cell line, MCF-7. Most significantly, compound 7 showed several folds enhanced activity against MCF-7 cancer cell lines (IC50: 2.96μM) than that of the parent (1) and the intermediate compound (6). Flow cytometric analysis revealed that these compounds arrested the cell cycle in G0/G1 phase and induced mitochondrial mediated apoptosis. PMID:27522460

  2. Immobilization of catalase on chitosan and amino acid- modified chitosan beads.

    PubMed

    Başak, Esra; Aydemir, Tülin

    2013-08-01

    Bovine liver catalase was covalently immobilized onto amino acid-modified chitosan beads. The beads were characterized with SEM, FTIR, TGA and the effects of immobilization on optimum pH and temperature, thermostability, reusability were evaluated. Immobilized catalase showed the maximal enzyme activity at pH 7.0 at 30°C. The kinetic parameters, Km and Vmax, for immobilized catalase on alanine-chitosan beads and lysine-chitosan beads were estimated to be 25.67 mM, 27 mM and 201.39 μmol H2O2/min, 197.50 μmol H2O2/min, respectively. The activity of the immobilized catalase on Ala-CB and Lys-CB retained 40% of its high initial activity after 100 times of reuse. PMID:23316810

  3. Synthesis of ring-C modified oleanolic acid derivatives and their cytotoxic evaluation.

    PubMed

    Pattnaik, Banita; Lakshma Nayak, Vadithe; Ramakrishna, Sistla; Venkata Mallavadhani, Uppuluri

    2016-10-01

    Ring-C of oleanolic acid was chemically modified by treating with NBS under a variety of experimental conditions. The structures of the synthesized compounds were established by spectral analysis ((1)H &(13)C NMR and Mass). All the compounds were evaluated against a panel of five human cancer cell lines by using MTT assay. Among the tested compounds, 2 and 7 showed significant activity against breast cancer cell line, MCF-7. Most significantly, compound 7 showed several folds enhanced activity against MCF-7 cancer cell lines (IC50: 2.96μM) than that of the parent (1) and the intermediate compound (6). Flow cytometric analysis revealed that these compounds arrested the cell cycle in G0/G1 phase and induced mitochondrial mediated apoptosis.

  4. Structure of the fully modified left-handed cyclohexene nucleic acid sequence GTGTACAC.

    PubMed

    Robeyns, Koen; Herdewijn, Piet; Van Meervelt, Luc

    2008-02-13

    CeNA oligonucleotides consist of a phosphorylated backbone where the deoxyribose sugars are replaced by cyclohexene moieties. The X-ray structure determination and analysis of a fully modified octamer sequence GTGTACAC, which is the first crystal structure of a carbocyclic-based nucleic acid, is presented. This particular sequence was built with left-handed building blocks and crystallizes as a left-handed double helix. The helix can be characterized as belonging to the (mirrored) A-type family. Crystallographic data were processed up to 1.53 A, and the octamer sequence crystallizes in the space group R32. The sugar puckering is found to adopt the 3H2 half-chair conformation which mimics the C3'-endo conformation of the ribose sugar. The double helices stack on top of each other to form continuous helices, and static disorder is observed due to this end-to-end stacking.

  5. Multifunctional nanosheets based on folic acid modified manganese oxide for tumor-targeting theranostic application

    NASA Astrophysics Data System (ADS)

    Hao, Yongwei; Wang, Lei; Zhang, Bingxiang; Zhao, Hongjuan; Niu, Mengya; Hu, Yujie; Zheng, Cuixia; Zhang, Hongling; Chang, Junbiao; Zhang, Zhenzhong; Zhang, Yun

    2016-01-01

    It is highly desirable to develop smart nanocarriers with stimuli-responsive drug-releasing and diagnostic-imaging functions for cancer theranostics. Herein, we develop a reduction and pH dual-responsive tumor theranostic platform based on degradable manganese dioxide (MnO2) nanosheets. The MnO2 nanosheets with a size of 20-60 nm were first synthesized and modified with (3-Aminopropyl) trimethoxysilane (APTMS) to get amine-functionalized MnO2, and then functionalized by NH2-PEG2000-COOH (PEG). The tumor-targeting group, folic acid (FA), was finally conjugated with the PEGylated MnO2 nanosheets. Then, doxorubicin (DOX), a chemotherapeutic agent, was loaded onto the modified nanosheets through a physical adsorption, which was designated as MnO2-PEG-FA/DOX. The prepared MnO2-PEG-FA/DOX nanosheets with good biocompatibility can not only efficiently deliver DOX to tumor cells in vitro and in vivo, leading to enhanced anti-tumor efficiency, but can also respond to a slightly acidic environment and high concentration of reduced glutathione (GSH), which caused degradation of MnO2 into manganese ions enabling magnetic resonance imaging (MRI). The longitudinal relaxation rate r 1 was 2.26 mM-1 s-1 at pH 5.0 containing 2 mM GSH. These reduction and pH dual-responsive biodegradable nanosheets combining efficient MRI and chemotherapy provide a novel and promising platform for tumor-targeting theranostic application.

  6. Photocatalytic decomposition of perfluorooctanoic acid by transition-metal modified titanium dioxide.

    PubMed

    Chen, Meng-Jia; Lo, Shang-Lien; Lee, Yu-Chi; Huang, Chang-Chieh

    2015-05-15

    Transition-metal modified TiO₂ was used in a UV reactor to assist in decomposition of perfluorooctanoic acid (PFOA) in aqueous solutions. Comparing TiO₂ and two types of metal-modified TiO₂ (Fe-TiO₂ and Cu-TiO₂), Cu-TiO₂ exhibited the highest catalytic activity during PFOA decomposition and defluorination. After 12 h of reaction, the PFOA decomposition and defluorination efficiencies by the UV/Cu-TiO₂ system reached 91% and 19%, respectively. PFOA was decomposed into fluoride ions (F(-)) and shorter perfluorinated carboxylic acids (PFCAs) such as C₆ F₁₃COOH, C₅F₁₁COOH, C₄F₉COOH, C₃F₇COOH, C₂F₅COOH and CF₃COOH. The pseudo-first-order and pseudo-zero-order kinetics were used to model the decomposition and defluorination of PFOA, respectively. Rate constant values of PFOA decomposition for the UV/TiO₂, UV/Fe-TiO₂, and UV/Cu-TiO₂ systems were 0.0001, 0.0015, and 0.0031 min(-1), respectively, while rate constant values of PFOA defluorination for the UV/Fe-TiO₂, and UV/Cu-TiO₂ systems were 0.0048 and 0.0077 mg/L·min(-1), respectively. The photocatalysts were prepared by a photodeposition synthesis method and were characterized by scanning electron microscopy with energy-dispersive X-ray, X-ray diffraction and UV-vis spectrophotometry. The Fe-TiO₂ and Cu-TiO₂ catalysts exhibited considerably higher activities than that of TiO₂. The experimental results have demonstrated that the UV/Fe-TiO₂ and UV/Cu-TiO₂ systems could produce traps to capture photo-induced electrons, thereby reduce electron-hole recombination during photocatalytic reactions and consequently enhance the PFOA decomposition.

  7. Physicochemical, thermal and computational study of the encapsulation of rumenic acid by natural and modified cyclodextrins.

    PubMed

    Matencio, Adrián; Hernández-Gil, Carlos Javier García; García-Carmona, Francisco; López-Nicolás, José Manuel

    2017-02-01

    In this work the aggregation behavior of Rumenic acid (RA) is presented for the first time. The results point to a c.m.c. of 35μM at pH 8 and 25°C. This behavior can be modified by introducing CDs into the system to encapsulate the RA. The encapsulation process presented a 1:1 stoichiometry in all the cases studied but the complexation constants were strongly dependent on the type of CDs used, the pH and temperature. Firstly, the effect of the type of CD on the encapsulation process was studied. Among the natural and modified CDs analyzed HPβCD was the best for encapsulating RA. The pKa determined for RA was 4.31. The KF showed different behavior below and above 25°C due to changes in the stoichiometry. Finally, molecular docking calculations provided further insights into how the different interactions influence the complexation constant. PMID:27596422

  8. Self-assembly and cytotoxicity study of PEG-modified ursolic acid liposomes.

    PubMed

    Zhao, Tingting; Liu, Yanping; Gao, Zhengrong; Gao, Dawei; Li, Nan; Bian, Yanhong; Dai, Kun; Liu, Zhiwei

    2015-08-01

    While ursolic acid (UA), one of the most broadly known triterpene compounds, has proved to be effective in cancer therapy, the applications of UA is limited due to its poor aqueous solubility and low bioavailability. The aim of our study was to prolong circulation time and enhance uptake of liposomes in tumor tissues through the modification of UA liposomes via water-soluble polyethylene glycol (PEG). In addition, this research also focuses on physicochemical properties of the liposome formulations, including encapsulation efficiency, particle morphology, size, stability, release rate in vitro and cytotoxicity test. The obtained liposomes were spherical particles with mean particle diameters around 100-200 nm. And the Fourier transform infrared spectroscopy (FTIR) indicated that PEG had been anchored successfully to the liposomes. Based on our experimental data achieved, PEG-modified UA liposomes possessed higher stability than conventional liposomes, and the release rate of UA from PEG-modified liposomes was slower when compared with those of UA solution and conventional liposomes. Meanwhile, the liposomal UA showed relatively low cytotoxic effect than UA conventional liposomes within 24h, which was consistent with their release rates. PMID:26042707

  9. Synthesis of porous starch xerogels modified with mercaptosuccinic acid to remove hazardous gardenia yellow.

    PubMed

    Bao, Liping; Zhu, Xinyi; Dai, Hongxia; Tao, Yongxin; Zhou, Xiaoying; Liu, Wenjie; Kong, Yong

    2016-08-01

    Mercaptosuccinic acid (MSA) molecules were inserted into potato starch, leading to the breaking of intrinsic H-bonds within macromolecular chains of starch and the formation of intermolecular H-bonds between MSA and starch, which could be verified by Fourier transform infrared spectroscopy (FT-TR). MSA modified porous starch xerogels (PSX/MSA) were obtained after freeze-drying the MSA modified starch, and they were characterized by field emission scanning electron microscopy (FESEM), exhibiting the intriguing porous structure due to the separation of starch chains by MSA molecules. The PSX/MSA were then used as the adsorbents to remove gardenia yellow (GY), a natural colorant with genotoxicity. Due to the porous structure of PSX and the introduced carboxyl groups from MSA, the adsorption capacity of the PSX/MSA was much higher than that of the starch xerogels alone (SX). The adsorption behaviors of GY by the PSX/MSA fitted both the Freundlich isotherm model and the pseudo-second-order kinetic model, and the efficient adsorption of GY suggested that the PSX/MSA might be potential adsorbents for the removal of dyes from contaminated aquatic systems. PMID:27151673

  10. Silane modified starch for compatible reactive blend with poly(lactic acid).

    PubMed

    Jariyasakoolroj, Piyawanee; Chirachanchai, Suwabun

    2014-06-15

    A reactive blend of poly(lactic acid) (PLA) and a surface modified starch by silane coupling agent to achieve compatibility is proposed. A detailed structural analysis by using (1)H-(1)H TOCSY NMR spectrum clarifies, for the first time, that chloropropyl trimethoxysilane (CPMS) forms covalent bonds with starch during starch modification and consequently forms covalent bonds with PLA in the step of blending to produce a reactive blend of PLA and CP-starch. The CP-starch covalently bound with PLA provides the compatibility between PLA and starch and also plays the role as nucleating agent as identified from a significant increase of degree of crystallinity (as high as 10-15 times), as well as induces chain mobility, as identified from a slight decrease in glass transition temperature (∼5-10°C). The PLA/CP-starch film performed as well as neat PLA with slight increases in tensile strength and elongation at break, as compared to other PLA/silane modified starch films. PMID:24721076

  11. Preparation, cell compatibility and degradability of collagen-modified poly(lactic acid).

    PubMed

    Cui, Miaomiao; Liu, Leili; Guo, Ning; Su, Ruixia; Ma, Feng

    2015-01-01

    Poly(lactic acid) (PLA) was modified using collagen through a grafting method to improve its biocompatibility and degradability. The carboxylic group at the open end of PLA was transferred into the reactive acylchlorided group by a reaction with phosphorus pentachloride. Then, collagen-modified PLA (collagen-PLA) was prepared by the reaction between the reactive acylchlorided group and amino/hydroxyl groups on collagen. Subsequently, the structure of collagen-PLA was confirmed by Fourier transform infrared spectroscopy, fluorescein isothiocyanate-labeled fluorescence spectroscopy, X-ray photoelectron spectroscopy, and DSC analyses. Finally, some properties of collagen-PLA, such as hydrophilicity, cell compatibility and degradability were characterized. Results showed that collagen had been grafted onto the PLA with 5% graft ratio. Water contact angle and water absorption behavior tests indicated that the hydrophilicity of collagen-PLA was significantly higher than that of PLA. The cell compatibility of collagen-PLA with mouse embryonic fibroblasts (3T3) was also significantly better than PLA in terms of cell morphology and cell proliferation, and the degradability of PLA was also improved after introducing collagen. Results suggested that collagen-PLA was a promising candidate for biomedical applications. PMID:25569516

  12. Deep Eutectic Solvents Modified Molecular Imprinted Polymers for Optimized Purification of Chlorogenic Acid from Honeysuckle.

    PubMed

    Li, Guizhen; Wang, Wei; Wang, Qian; Zhu, Tao

    2016-02-01

    Deep eutectic solvents (DES) were synthesized with choline chloride (ChCl), and DES modified molecular imprinted polymers (DES-MIPs), DES modified non-imprinted polymers (DES-NIPs, without template), MIPs and NIPs were prepared in an identical procedure. Fourier transform infrared spectrometer (FT-IR) and field emission scanning electron microscopy (FE-SEM) were used to characterize the obtained polymers. Rebinding experiment and solid-phase extraction (SPE) were used to prove the high selectivity adsorption properties of the polymers. Box-Behnken design (BBD) with three factors was used to optimize the extraction condition of chlorogenic acid (CA) from honeysuckles. The optimum extraction conditions were found to be ultrasonic time optimized (20 min), the volume fraction of ethanol (60%) and ratio of liquid to material (15 mL g(-1)). Under these conditions, the mean extraction yield of CA was 12.57 mg g(-1), which was in good agreement with the predicted BBD model value. Purification of hawthorn extract was achieved by SPE process, and SPE recoveries of CA were 72.56, 64.79, 69.34 and 60.08% by DES-MIPs, DES-NIPs, MIPs and NIPs, respectively. The results showed DES-MIPs had potential for promising functional adsorption material for the purification of bioactive compounds.

  13. Solid lipid nanoparticles modified with stearic acid-octaarginine for oral administration of insulin.

    PubMed

    Zhang, Zhen-Hai; Zhang, Yin-Long; Zhou, Jian-Ping; Lv, Hui-Xia

    2012-01-01

    The aim of this study was to design and characterize solid lipid nanoparticles (SLNs) modified with stearic acid-octaarginine (SA-R₈) as carriers for oral administration of insulin (SA-R₈-Ins-SLNs). The SLNs were prepared by spontaneous emulsion solvent diffusion methods. The mean particle size, zeta potential, drug loading, and encapsulation efficiency of the SA-R₈-Ins-SLNs were 162 nm, 29.87 mV, 3.19%, and 76.54%, respectively. The zeta potential of the SLNs changed dramatically, from -32.13 mV to 29.87 mV, by binding the positively charged SA-R₈. Morphological studies of SA-R₈-Ins-SLNs using transmission electron microscopy showed that they were spherical. In vitro, a degradation experiment by enzymes showed that SLNs and SA-R₈ could partially protect insulin from proteolysis. Compared to the insulin solution, the SA-R₈-Ins-SLNs increased the Caco-2 cell's internalization by up to 18.44 times. In the in vivo studies, a significant hypoglycemic effect in diabetic rats over controls was obtained, with a SA-R₈-Ins-SLN pharmacological availability value of 13.86 ± 0.79. These results demonstrate that SA-R₈-modified SLNs promote the oral absorption of insulin.

  14. Ribonuclease H1-dependent hepatotoxicity caused by locked nucleic acid-modified gapmer antisense oligonucleotides.

    PubMed

    Kasuya, Takeshi; Hori, Shin-Ichiro; Watanabe, Ayahisa; Nakajima, Mado; Gahara, Yoshinari; Rokushima, Masatomo; Yanagimoto, Toru; Kugimiya, Akira

    2016-01-01

    Gapmer antisense oligonucleotides cleave target RNA effectively in vivo, and is considered as promising therapeutics. Especially, gapmers modified with locked nucleic acid (LNA) shows potent knockdown activity; however, they also cause hepatotoxic side effects. For developing safe and effective gapmer drugs, a deeper understanding of the mechanisms of hepatotoxicity is required. Here, we investigated the cause of hepatotoxicity derived from LNA-modified gapmers. Chemical modification of gapmer's gap region completely suppressed both knockdown activity and hepatotoxicity, indicating that the root cause of hepatotoxicity is related to intracellular gapmer activity. Gene silencing of hepatic ribonuclease H1 (RNaseH1), which catalyses gapmer-mediated RNA knockdown, strongly supressed hepatotoxic effects. Small interfering RNA (siRNA)-mediated knockdown of a target mRNA did not result in any hepatotoxic effects, while the gapmer targeting the same position on mRNA as does the siRNA showed acute toxicity. Microarray analysis revealed that several pre-mRNAs containing a sequence similar to the gapmer target were also knocked down. These results suggest that hepatotoxicity of LNA gapmer is caused by RNAseH1 activity, presumably because of off-target cleavage of RNAs inside nuclei. PMID:27461380

  15. Ribonuclease H1-dependent hepatotoxicity caused by locked nucleic acid-modified gapmer antisense oligonucleotides

    PubMed Central

    Kasuya, Takeshi; Hori, Shin-ichiro; Watanabe, Ayahisa; Nakajima, Mado; Gahara, Yoshinari; Rokushima, Masatomo; Yanagimoto, Toru; Kugimiya, Akira

    2016-01-01

    Gapmer antisense oligonucleotides cleave target RNA effectively in vivo, and is considered as promising therapeutics. Especially, gapmers modified with locked nucleic acid (LNA) shows potent knockdown activity; however, they also cause hepatotoxic side effects. For developing safe and effective gapmer drugs, a deeper understanding of the mechanisms of hepatotoxicity is required. Here, we investigated the cause of hepatotoxicity derived from LNA-modified gapmers. Chemical modification of gapmer’s gap region completely suppressed both knockdown activity and hepatotoxicity, indicating that the root cause of hepatotoxicity is related to intracellular gapmer activity. Gene silencing of hepatic ribonuclease H1 (RNaseH1), which catalyses gapmer-mediated RNA knockdown, strongly supressed hepatotoxic effects. Small interfering RNA (siRNA)-mediated knockdown of a target mRNA did not result in any hepatotoxic effects, while the gapmer targeting the same position on mRNA as does the siRNA showed acute toxicity. Microarray analysis revealed that several pre-mRNAs containing a sequence similar to the gapmer target were also knocked down. These results suggest that hepatotoxicity of LNA gapmer is caused by RNAseH1 activity, presumably because of off-target cleavage of RNAs inside nuclei. PMID:27461380

  16. Deep Eutectic Solvents Modified Molecular Imprinted Polymers for Optimized Purification of Chlorogenic Acid from Honeysuckle.

    PubMed

    Li, Guizhen; Wang, Wei; Wang, Qian; Zhu, Tao

    2016-02-01

    Deep eutectic solvents (DES) were synthesized with choline chloride (ChCl), and DES modified molecular imprinted polymers (DES-MIPs), DES modified non-imprinted polymers (DES-NIPs, without template), MIPs and NIPs were prepared in an identical procedure. Fourier transform infrared spectrometer (FT-IR) and field emission scanning electron microscopy (FE-SEM) were used to characterize the obtained polymers. Rebinding experiment and solid-phase extraction (SPE) were used to prove the high selectivity adsorption properties of the polymers. Box-Behnken design (BBD) with three factors was used to optimize the extraction condition of chlorogenic acid (CA) from honeysuckles. The optimum extraction conditions were found to be ultrasonic time optimized (20 min), the volume fraction of ethanol (60%) and ratio of liquid to material (15 mL g(-1)). Under these conditions, the mean extraction yield of CA was 12.57 mg g(-1), which was in good agreement with the predicted BBD model value. Purification of hawthorn extract was achieved by SPE process, and SPE recoveries of CA were 72.56, 64.79, 69.34 and 60.08% by DES-MIPs, DES-NIPs, MIPs and NIPs, respectively. The results showed DES-MIPs had potential for promising functional adsorption material for the purification of bioactive compounds. PMID:26347506

  17. Silane modified starch for compatible reactive blend with poly(lactic acid).

    PubMed

    Jariyasakoolroj, Piyawanee; Chirachanchai, Suwabun

    2014-06-15

    A reactive blend of poly(lactic acid) (PLA) and a surface modified starch by silane coupling agent to achieve compatibility is proposed. A detailed structural analysis by using (1)H-(1)H TOCSY NMR spectrum clarifies, for the first time, that chloropropyl trimethoxysilane (CPMS) forms covalent bonds with starch during starch modification and consequently forms covalent bonds with PLA in the step of blending to produce a reactive blend of PLA and CP-starch. The CP-starch covalently bound with PLA provides the compatibility between PLA and starch and also plays the role as nucleating agent as identified from a significant increase of degree of crystallinity (as high as 10-15 times), as well as induces chain mobility, as identified from a slight decrease in glass transition temperature (∼5-10°C). The PLA/CP-starch film performed as well as neat PLA with slight increases in tensile strength and elongation at break, as compared to other PLA/silane modified starch films.

  18. Acid modified diatomaceous earth--a sorbent material for thin layer chromatography.

    PubMed

    Ergül, Soner; Savaşci, Sahin

    2008-04-01

    Natural diatomaceous earth (DE) is modified by flux calcination and refluxing with acid. To characterize natural DE, modified DE's [flux calcinated (FC)DE and FCDE-I] and silica gel 60GF(254) (Si-60GF(254)) are analyzed microscopically, physically, and chemically by various techniques. FCDE-I and Si-60GF(254) are investigated for their usefulness in the stationary phase of thin layer chromatography (TLC) both individually and in composition. Sodium diethyldithiocarbamate (DEDTC) and ammonium pyrrolidinedithiocarbamate (PyDTC) are prepared as Co or Cu (M) complexes [M(DEDTC)(2) and M(PyDTC)(2), respectively]. These complexes and their mixtures are run on thin layers of Si-60GF(254) and FCDE-I individually, and on various FCDE-I and Si-60GF(254) mixtures. Pure toluene and various toluene-cyclohexane mixtures (3:1, 1:1, 1:2, 1:3, v/v) are used as mobile phases for the running the complexes. The best analytical separations of both M(DEDTC)(2) and M(PyDTC)(2) complexes are obtained when using pure toluene and toluene-cyclohexane (3:1, 1:1, v/v) as mobile phases on FCDE-I-Si-60GF(254) (1:3, 1:1, w/w) layers as stationary phases. This study shows that it is possible to qualitatively analyze and to satisfactorily separate a mixture Cu(2+) and Co(2+) cations on cited chromatographic systems. PMID:18402721

  19. The use of the maharanobis and modified distances for the improvement of simulation of glutamic acid production.

    PubMed

    Kishimoto, M; Alfafara, C G; Nakajima, M; Yoshida, T; Taguchi, H

    1989-01-10

    A modified simulation procedure based on a statistical approach was investigated. The procedure predicts the time course of fed-batch culture for glutamic acid production by a temperature-sensitive strain of Brevibacterium flavum. The statistical approach requires only a data base of state points obtained in experiments, and not perfect identification of fermentation models. The simulation procedure is based on regression analysis to estimate specific rate parameters of system equations using the data points selected with reference to the Euclid distance. It was modified in that the data selection procedure included the use of the Maharanobis distance as well as a modified distance defined in this study. Simulation results using the modified procedure allow reasonable prediction of the time course of fed-batch culture for glutamic acid compared to that involving the Euclid distance alone.

  20. Metabolism of gamma-aminobutyric acid during cold acclimation and freezing and its relationship to frost tolerance in barley and wheat.

    PubMed

    Mazzucotelli, Elisabetta; Tartari, Alfredo; Cattivelli, Luigi; Forlani, Giuseppe

    2006-01-01

    Amino acid homeostasis was investigated in frost-resistant barley seedlings under either cold- or freezing-stress conditions. Total free amino acid content varied only slightly, but a substantial conversion of glutamate to gamma-aminobutyric acid (GABA) was found that was proportional to the severity of the stress. Cold acclimation caused a significant increase in amino acid pools, and induced the expression of the GABA-shunt genes. As a consequence, GABA accumulated to a higher extent during the subsequent exposure to lower temperature. A different picture was obtained with a frost-sensitive genotype, in which glutamate decarboxylation occurred during the stress as well, but the activation of the GABA shunt seemed not to take place, and free glutamate was almost depleted. Analogous results were found in frost-resistant and frost-sensitive wheat cultivars. Feeding non-hardened plants with exogenous glutamate resulted in increased GABA accumulation under low temperature. The possibility that glutamate decarboxylation and GABA metabolism would play a role in frost tolerance is discussed. PMID:16997899

  1. Wheat: The Whole Story.

    ERIC Educational Resources Information Center

    Oklahoma State Dept. of Education, Oklahoma City.

    This publication presents information on wheat. Wheat was originally a wild grass and not native to the United States. Wheat was not planted there until 1777 (and then only as a hobby crop). Wheat is grown on more acres than any other grain in this country. Soft wheats are grown east of the Mississippi River, and hard wheats are grown west of the…

  2. SBA-15 mesoporous material modified with APTES as the carrier for 2-(3-benzoylphenyl)propionic acid

    NASA Astrophysics Data System (ADS)

    Moritz, Michał; Łaniecki, Marek

    2012-07-01

    SBA-15 ordered mesoporous silica functionalized with (3-aminopropyl)triethoxysilane (APTES) was used as the carrier for anti-inflammatory drug: 2-(3-benzoylphenyl)propionic acid - ketoprofen. The surface of SBA-15 containing free silanol groups was modified with 3-aminopropyltriethoxysilane via post-synthetic reaction. Functionalization of the carrier with basic aminopropyl groups resulted in an ionic interaction with acidic ketoprofen. The samples of carriers and carrier-drug complexes were characterized by elemental analysis, TG, N2 adsorption, FTIR, DRUV spectroscopies and an in vitro drug release test. The adsorption of ketoprofen on modified mesoporous matrix was proportional to the amount of introduced aminopropyl groups. The maximum content of deposited drug in modified SBA-15 was close to 20 wt.%. After drug adsorption the reduction of BET surface area, pore volume and pore diameter of non-modified SBA-15 and aminopropyl-modified SBA-15 after drug adsorption were observed while the hexagonal array of siliceous matrix was well preserved. The release profiles of the aminopropyl-modified drug-containing SBA-15 exhibited prolonged release of ketoprofen in applied media. Tests performed in acidic solution (pH 1.2) showed the best pharmaceutical availability.

  3. Determination of DNA adducts by combining acid-catalyzed hydrolysis and chromatographic analysis of the carcinogen-modified nucleobases.

    PubMed

    Leung, Elvis M K; Deng, Kailin; Wong, Tin-Yan; Chan, Wan

    2016-01-01

    The commonly used method of analyzing carcinogen-induced DNA adducts involves the hydrolysis of carcinogen-modified DNA samples by using a mixture of enzymes, followed by (32)P-postlabeling or liquid chromatography (LC)-based analyses of carcinogen-modified mononucleotides/nucleosides. In the present study, we report the development and application of a new approach to DNA adduct analysis by combining the H(+)/heat-catalyzed release of carcinogen-modified nucleobases and the use of LC-based methods to analyze DNA adducts. Results showed that heating the carcinogen-modified DNA samples at 70 °C for an extended period of 4 to 6 h in the presence of 0.05% HCl can efficiently induce DNA depurination, releasing the intact carcinogen-modified nucleobases for LC analyses. After optimizing the hydrolysis conditions, DNA samples with C8- and N (2) -modified 2'-deoxyguanosine, as well as N (6) -modified 2'-deoxyadenosine, were synthesized by reacting DNA with 1-nitropyrene, acetaldehyde, and aristolochic acids, respectively. These samples were then hydrolyzed, and the released nucleobase adducts were analyzed using LC-based analytical methods. Analysis results demonstrated a dose-dependent release of target DNA adducts from carcinogen-modified DNA samples, indicating that the developed H(+)/heat-catalyzed hydrolysis method was quantitative. Comparative studies with enzymatic digestion method on carcinogen-modified DNA samples revealed that the two hydrolysis methods did not yield systematically different results.

  4. Carminic acid modified anion exchanger for the removal and preconcentration of Mo(VI) from wastewater.

    PubMed

    El-Moselhy, Medhat Mohamed; Sengupta, Arup K; Smith, Ryan

    2011-01-15

    Removal and preconcentration of Mo(VI) from water and wastewater solutions was investigated using carminic acid modified anion exchanger (IRA743). Various factors influencing the adsorption of Mo(VI), e.g. pH, initial concentration, and coexisting oxyanions were studied. Adsorption reached equilibrium within <10 min and was independent of initial concentration of Mo(VI). Studies were performed at different pH values to find the pH at which maximum adsorption occurred and was determined to be at a pH between 4.0 and 6.0. The Langmuir adsorption capacity (q(max)) was found to be 13.5mg Mo(VI)/g of the adsorbent. The results showed that modification of IRA743 with carminic acid is suitable for the removal of Mo(VI), as molybdate, from water and wastewater samples. The concentration of Mo(VI) was determined spectrophotometrically using bromopyrogallol red as a complexation reagent. This allows the determination of Mo(VI) in the range 1.0-100.0 μg/mL. The obtained material was subjected to efficient regeneration. PMID:20943315

  5. Biodistribution profiling of the chemical modified hyaluronic acid derivatives used for oral delivery system.

    PubMed

    Hsieh, Chien-Ming; Huang, Yu-Wen; Sheu, Ming-Thau; Ho, Hsiu-O

    2014-03-01

    A series of adipic acid dihydrazide (ADH)-modified hyaluronic acid (HA-ADH) compounds were synthesized and conjugated with QDots (QDots-HA conjugates) to assess the effects of the molecular weight (MW) and extent of chemical modification of HA on its biodistribution. Their physicochemical structures were confirmed by complementary application of GPC, (1)H NMR, FTIR, and UV-vis spectroscopic methods. In vivo imaging of QDots-HA conjugates after oral administration was analyzed to investigate their biodistribution in nude mice. Simultaneously, real-time bioimaging was confirmed by an anatomical analysis to investigate the organ-specific accumulation of conjugates. QDot-HA conjugates with a higher MW of HA or high modification presented relatively slow clearance leading to an extension of the retention time for up to 10 days, whereas those with lower MWs of HA or a low modification extent exhibited quick absorption and elimination after oral administration. Taken together, HA derivatives with suitable MWs and chemical modification extents can be used to design new, more-sophisticated, and intelligent HA-based vehicles for oral delivery with diverse characteristics. PMID:24315950

  6. Electrocatalytic oxidation of salicylic acid by a cobalt hydrotalcite-like compound modified Pt electrode.

    PubMed

    Gualandi, Isacco; Scavetta, Erika; Zappoli, Sergio; Tonelli, Domenica

    2011-03-15

    In this paper a study of the electrocatalytic oxidation of salicylic acid (SA) at a Pt electrode coated with a Co/Al hydrotalcite-like compound (Co/Al HTLC coated-Pt) film is presented. The voltammetric behaviour of the modified electrode in 0.1M NaOH shows two different redox couples: Co(II)/Co(III) and Co(III)/Co(IV). The electrocatalysis occurs at the same potential of the latter couple, showing that Co(IV) centers act as the oxidant. The CV investigation demonstrates that the process is controlled both by mass and charge transfer and that the Co(IV) centers involved in the oxidation are two for each SA molecule. The estimated value of the catalytic constant is 4×10(4) M(-1) s(-1). The determination of salicylic acid was performed both by DPV and chronoamperometry. The linearity ranges and the LOD values resulted 1×10(-5) to 5×10(-4), 5×10(-7) to 1×10(-4), 6×10(-6) and 2×10(-7) M, respectively. The Co/Al HTLC electrode has been used for SA determination in BAYER Aspirina® and the obtained results are consistent with an independent HPLC analysis. PMID:21237633

  7. Efficient gene delivery system mediated by cis-aconitate-modified chitosan-g-stearic acid micelles.

    PubMed

    Yao, Jing-Jing; Du, Yong-Zhong; Yuan, Hong; You, Jian; Hu, Fu-Qiang

    2014-01-01

    Cis-aconitate-modified chitosan-g-stearic acid (CA-CSO-SA) micelles were synthesized in this study to improve the gene transfection efficiency of chitosan-g-stearic acid (CSO-SA). The CA-CSO-SA micelles had a similar size, critical micelle concentration, and morphology, but their zeta potential and cytotoxicity were reduced compared with CSO-SA micelles. After modification with cis-aconitate, the CA-CSO-SA micelles could also compact plasmid DNA (pDNA) to form nanocomplexes. However, the DNA binding ability of CA-CSO-SA was slightly reduced compared with that of CSO-SA. The transfection efficiency mediated by CA-CSO-SA/pDNA against HEK-293 cells reached up to 37%, and was much higher than that of CSO-SA/pDNA (16%). Although the cis-aconitate modification reduced cellular uptake kinetics in the initial stages, the total amount of cellular uptake tended to be the same after 24 hours of incubation. An endocytosis inhibition experiment showed that the internalization mechanism of CA-CSO-SA/pDNA in HEK-293 cells was mainly via clathrin-mediated endocytosis, as well as caveolae-mediated endocytosis and macropinocytosis. Observation of intracellular trafficking indicated that the CSO-SA/pDNA complexes were trapped in endolysosomes, but CA-CSO-SA/pDNA was more widely distributed in the cytosol. This study suggests that modification with cis-aconitate improves the transfection efficiency of CSO-SA/pDNA.

  8. Interactions between organic amendments and phosphate fertilizers modify phosphate sorption processes in an acid soil

    SciTech Connect

    Sckefe, C.R.; Patti, A.F.; Clune, T.S.; Jackson, W.R.

    2008-07-15

    To determine how organic amendments and phosphate fertilizers interact to modify P sorption processes, three phosphate fertilizers were applied to lignite- and compost-amended acid soil and incubated for either 3 or 26 days. The fertilizers applied were potassium dihydrogen phosphate, triple superphosphate, and diammonium phosphate (DAP). After 3 days of incubation, sorption of all three P sources was decreased in the lignite-amended treatments, whereas P sorption was increased in the compost-amended treatments. Increased incubation time (26 days) resulted in significantly decreased P sorption when DAP was added to lignite-amended treatments. Addition of triple superphosphate increased P sorption in lignite- and compost-amended treatments and decreased solution pH compared with DAP application. In addition to the effect of P source, differences in P sorption between the lignite- and compost-amended treatments were driven by differences in solution chemistry, predominantly solution pH and cation dynamics. Soil amendment and fertilizer addition also increased microbial activity in the incubation systems, as measured by carbon dioxide respiration. It is proposed that the combination of lignite and DAP may contribute to decreased P sorption in acid soils, with the positive effects likely caused by both chemical and biological processes, including the formation of soluble organic-metal complexes.

  9. DNA immobilization on a polypyrrole nanofiber modified electrode and its interaction with salicylic acid/aspirin.

    PubMed

    Yousef Elahi, M; Bathaie, S Z; Kazemi, S H; Mousavi, M F

    2011-04-15

    A double-stranded calf thymus DNA (dsDNA) was physisorbed onto a polypyrrole (PPy) nanofiber film that had been electrochemically deposited onto a Pt electrode. The surface morphology of the polymeric film was characterized using scanning electron microscopy (SEM). The electrochemical characteristics of the PPy film and the DNA deposited onto the PPy modified electrode were investigated by cyclic voltammetry (CV), differential pulse voltammetry (DPV), and electrochemical impedance spectroscopy (EIS). Then the interaction of DNA with salicylic acid (SA) and acetylsalicylic acid (ASA), or aspirin, was studied on the electrode surface with DPV. An increase in the DPV current was observed due to the oxidation of guanine, which decreased with the increasing concentrations of the ligands. The interactions of SA and ASA with the DNA follow the saturation isotherm behavior. The binding constants of these interactions were 1.15×10(4)M for SA and 7.46×10(5)M for ASA. The numbers of binding sites of SA and ASA on DNA were approximately 0.8 and 0.6, respectively. The linear dynamic ranges of the sensors were 0.1-2μM (r(2)=0.996) and 0.05-1mM (r(2)=0.996) with limits of detection of 8.62×10(-1) and 5.24×10(-6)μM for SA and ASA, respectively.

  10. Electrocatalytic oxidation of salicylic acid by a cobalt hydrotalcite-like compound modified Pt electrode.

    PubMed

    Gualandi, Isacco; Scavetta, Erika; Zappoli, Sergio; Tonelli, Domenica

    2011-03-15

    In this paper a study of the electrocatalytic oxidation of salicylic acid (SA) at a Pt electrode coated with a Co/Al hydrotalcite-like compound (Co/Al HTLC coated-Pt) film is presented. The voltammetric behaviour of the modified electrode in 0.1M NaOH shows two different redox couples: Co(II)/Co(III) and Co(III)/Co(IV). The electrocatalysis occurs at the same potential of the latter couple, showing that Co(IV) centers act as the oxidant. The CV investigation demonstrates that the process is controlled both by mass and charge transfer and that the Co(IV) centers involved in the oxidation are two for each SA molecule. The estimated value of the catalytic constant is 4×10(4) M(-1) s(-1). The determination of salicylic acid was performed both by DPV and chronoamperometry. The linearity ranges and the LOD values resulted 1×10(-5) to 5×10(-4), 5×10(-7) to 1×10(-4), 6×10(-6) and 2×10(-7) M, respectively. The Co/Al HTLC electrode has been used for SA determination in BAYER Aspirina® and the obtained results are consistent with an independent HPLC analysis.

  11. Synthesis of poly acrylic acid modified silver nanoparticles and their antimicrobial activities.

    PubMed

    Ni, Zhihui; Wang, Zhihua; Sun, Lei; Li, Binjie; Zhao, Yanbao

    2014-08-01

    Poly acrylic acid modified silver (Ag/PAA) nanoparticles (NPs) have been successfully synthesized in the aqueous solution by using tannic acid as a reductant. The structure, morphology and composition of Ag/PAA NPs were characterized by various techniques such as X-ray powder diffraction (XRD), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), ultraviolet-visible absorption spectroscopy (UV-vis) and thermogravimetry analysis (TGA). The results show that PAA/Ag NPs have a quasi-ball shape with an average diameter of 10 nm and exhibit well crystalline, and the reaction conditions have some effect on products morphology and size distribution. In addition, the as-synthesized Ag/PAA NPs antimicrobial activities against Escherichia coli (E. coli), Pseudomonas aeruginosa (P. aeruginosa) and Staphylococcus aureus (S. aureus) were evaluated by the methods of broth dilution, cup diffusion, optical density (OD600) and electron microscopy observation. The as-synthesized Ag/PAA NPs exhibit excellent antibacterial activity. The antimicrobial mechanism may be attributed to the damaging of bacterial cell membrane and causing leakage of cytoplasm. PMID:24907758

  12. Formic acid electrooxidation on Bi-modified polyoriented and preferential (111) Pt nanoparticles.

    PubMed

    López-Cudero, Ana; Vidal-Iglesias, Francisco J; Solla-Gullón, José; Herrero, Enrique; Aldaz, Antonio; Feliu, Juan M

    2009-01-14

    Formic acid electrooxidation was studied on Bi modified polyoriented and preferential (111) Pt nanoparticles. For both types of nanoparticles, Bi coverage was progressively increased and its effect on formic acid electrooxidation was evaluated using cyclic voltammetry and chronoamperometric measurements. In both experiments, significant and progressive enhancements on the electrooxidation current densities were obtained in comparison to the bare Pt nanoparticles. In voltammetry, at maximum Bi coverage, higher current densities at peak potential were obtained with the preferential (111) Pt nanoparticles (approximately 42 mA cm(-2)) as compared to the polyoriented Pt nanoparticles (approximately 32 mA cm(-2)) in agreement with previous single crystal studies. Nevertheless, this tendency was not observed in chronoamperometry at 0.4 V where currents obtained at maximum Bi coverage were similar. On the other hand, CO poison formation was also evaluated at open circuit potential. The resulting electrochemical activity has been rationalized using different parameters, such as surface structure, size domains, particle size and Bi coverage. PMID:19088999

  13. Binding of actin to thioglycolic acid modified superparamagnetic nanoparticles for antibody conjugation.

    PubMed

    Maltas, Esra; Ertekin, Betul

    2015-01-01

    Thioglycolic acid modified superparamagnetic iron oxide nanoparticles (TG-APTS-SPION) were synthesized by using (3-aminopropyl) triethoxysilane (APTS) and thioglycolic acid (TG). Actin was immobilized on the nanoparticle surfaces. Binding amount of the actin (Act) on TG-APTS-SPIONs was determined by using a calibration curve equation that was drawn using fluorescence spectra at 280 and 342 nm of excitation and emission wavelengths. Anti-Actin (anti-Act) was interacted with the actin immobilized TG-APTS-SPIONs as primary antibody. Horse radish peroxidase (HRP) was also interacted with antibody conjugated nanoparticles as secondary antibody. The binding capacity of primary and secondary antibodies was also estimated by fluorescence spectroscopy. Scanning electron microscopy (SEM), Infrared spectroscopy (FTIR) and energy dispersive X-ray (EDX) analysis were also clarified binding of the protein and antibodies to the nanoparticles' surfaces. Western blot analysis was also done for actin conjunction with anti Act antibody to confirm binding of the antibody to the protein. PMID:25451750

  14. Novel Long-Circulating Liposomes Consisting of PEG Modified β-Sitosterol for Gambogic Acid Delivery.

    PubMed

    Yu, Fan; Tang, Xinhui

    2016-03-01

    Long-circulating liposome is an effective formulation in field of cancer treatment. However, high expenditure of formulation and high dose of cholesterol severely restrict its application. In this paper, we developed a method by grafting polyethylene glycol 2000 on β-sitosterol succinic anhydride ester to obtain relatively cheap polyethylene glycol-β-sitosterol conjugates, which were used to prepare long-circulating liposome without cholesterol. Gambogic acid which is an effective antitumor ingredient with very short half-life, was used as a model drug to prepare long-circulating liposome in this research. Meanwhile, the characteristics, pharmacokinetics and distribution of this novel long-circulating liposome were also investigated in comparison with other gambogic acid formulations. Polyethylene glycol-β-sitosterol conjugates were synthesized, different liposomal formulations were also prepared by ethanol injection method, and the obtained nanoparticles were characterized by dynamic light scattering and transmission electron microscope. The long-circulating effect, pharmacokinetics and distribution of gambogic acid in rats were also explored. 1HNMR confirmed that polyethylene glycol-β-sitosterol conjugates were synthesized successfully. Novel long-circulating liposome was successfully prepared by ethanol injection method attaining a entrapment efficiency of 89.4%, exhibiting a homogeneous particle size of 245.2 nm and -24.3 mV zeta potential with smooth continuous surface. This novel long-circulating liposome demonstrated better long-circulating effect than ordinary long-circulating liposome. The novel long-circulating liposome as-prepared not only could reduce cost of grafting polyethylene glycol on macromolecular phospholipid, but also no cholestrol in preparation was applied, expanding the application of liposome as a formulation in the field of lowering blood lipid. Therefore, polyethylene glycol-β-sitosterol conjugates are recommended substitute for

  15. Improving wheat to remove coeliac epitopes but retain functionality

    PubMed Central

    Shewry, Peter R.; Tatham, Arthur S.

    2016-01-01

    Coeliac disease is an intolerance triggered by the ingestion of wheat gluten proteins. It is of increasing concern to consumers and health professionals as its incidence appears to be increasing. The amino acid sequences in gluten proteins that are responsible for triggering responses in sensitive individuals have been identified showing that they vary in distribution among and between different groups of gluten proteins. Conventional breeding may therefore be used to select for gluten protein fractions with lower contents of coeliac epitopes. Molecular breeding approaches can also be used to specifically down-regulate coeliac-toxic proteins or mutate coeliac epitopes within individual proteins. A combination of these approaches may therefore be used to develop a “coeliac-safe” wheat. However, this remains a formidable challenge due to the complex multigenic control of gluten protein composition. Furthermore, any modified wheats must retain acceptable properties for making bread and other processed foods. Not surprisingly, such coeliac-safe wheats have not yet been developed despite over a decade of research. PMID:26937068

  16. Effect of the eluent pH and acidic modifiers in high-performance liquid chromatography retention of basic analytes.

    PubMed

    LoBrutto, R; Jones, A; Kazakevich, Y V; McNair, H M

    2001-04-13

    The retention of ionogenic bases in liquid chromatography is strongly dependent upon the pH of the mobile phase. Chromatographic behavior of a series of substituted aniline and pyridine basic compounds has been studied on C18 bonded silica using acetonitrile-water (10:90) as the eluent with different pHs and at various concentrations of the acidic modifier counter anions. The effect of different acidic modifiers on solute retention over a pH range from 1.3 to 8.6 was studied. Ionized basic compounds showed increased retention with a decrease of the mobile phase pH. This increase in retention was attributed to the interaction with counter anions of the acidic modifiers. The increase in retention is dependent on the nature of the counter anion and its concentration in the mobile phase. It was shown that altering the concentration of counter anion of the acidic modifier allows the optimization of the selectivity between basic compounds as well as for neutral and acidic compounds. PMID:11355811

  17. [Effects of long-term rotation on the nutritional quality of wheat grain protein on dryland of Loess Plateau, Northwest China].

    PubMed

    Cai, Yan; Hao, Ming-De

    2013-05-01

    A long-term experiment was conducted on the dryland of Loess Plateau to study the effects of three typical rotation systems, including wheat-sainfoin rotation, wheat-pea rotation, and wheat-maize rotation, on the nutritional quality of wheat grain protein. Rotation system and the cropping years of rotated plants affected the nutritional quality of wheat grain protein in varying degrees. As compared with continuous wheat cropping, wheat-sainfoin rotation made the nutritional quality of wheat grain protein relatively stable, and the essential amino acid content, amino acid score, amino acid ratio coefficient, chemical score, and amino acid index of the protein all relatively high, being able to be adopted as a cropping system to product high quality protein wheat in Loess Plateau. Under wheat-pea rotation, the nutritional quality of wheat grain protein after 1-year pea cropping was relatively high, but the essential amino acid content of wheat grain protein after 2-year pea cropping was relatively low, and several essential amino acid scores and chemical score of the grain protein were lower than those under continuous wheat cropping. Furthermore, the essential amino acid index was 12.2% lower than that under continuous wheat cropping. Therefore, wheat-pea rotation showed a relatively low nutritional quality of wheat grain protein. Under wheat-maize rotation, the nutritional quality of wheat grain protein was also relatively stable, but the crude protein and essential amino acid contents and amino acid balance level were lower than those under continuous wheat cropping.

  18. Dietary n-3 polyunsaturated fatty acids modify fatty acid composition in hepatic and abdominal adipose tissue of sucrose-induced obese rats.

    PubMed

    Alexander-Aguilera, Alfonso; Berruezo, Silvia; Hernández-Diaz, Guillermo; Angulo, Ofelia; Oliart-Ros, Rosamaria

    2011-12-01

    The fatty acid profile of hepatocytes and adipocytes is determined by the composition of the dietary lipids. It remains unclear which fatty acid components contribute to the development or reduction of insulin resistance. The present work examined the fatty acid composition of both tissues in sucrose-induced obese rats receiving fish oil to determine whether the effect of dietary (n-3) polyunsaturated fatty acids (PUFAs) on the reversion of metabolic syndrome in these rats is associated to changes in the fatty acid composition of hepatocyte and adipocyte membrane lipids. Animals with metabolic syndrome were divided into a corn-canola oil diet group and a fish oil diet group, and tissues fatty acids composition were analyzed after 6 weeks of dietary treatment. Fatty acid profiles of the total membrane lipids were modified by the fatty acid composition of the diets fed to rats. N-3 PUFAs levels in animals receiving the fish oil diet plus sucrose in drinking water were significantly higher than in animals under corn-canola oil diets. It is concluded that in sucrose-induced obese rats, consumption of dietary fish oil had beneficial effects on the metabolic syndrome and that such effects would be conditioned by the changes in the n-3 PUFAs composition in hepatic and adipose tissues because they alter membrane properties and modify the type of substrates available for the production of active lipid metabolites acting on insulin resistance and obesity. PMID:21695545

  19. The effectiveness of a modified hydrochloric acid-quartz-pumice abrasion technique on fluorosis stains: a case report.

    PubMed

    Erdogan, G

    1998-02-01

    Endemic dental fluorosis is a form of enamel hypoplasia characterized by moderate-to-severe staining of the tooth surface. Since 1916, numerous investigators have used hydrochloric acid alone on fluorosis stains. More recently, 18% hydrochloric acid-pumice microabrasion has been used to achieve color modification. The main disadvantage of this procedure is the high concentration and low viscosity of hydrochloric acid, which can cause damage to oral and dental tissues. To eliminate this problem, quartz particles can be mixed with the hydrochloric acid. The quartz particles prevent the hydrochloric acid from flowing uncontrollablely by altering it to a gel-like form. A modified 18% hydrochloric acid-quartz-pumice abrasion technique was used to remove fluorine stains from vital teeth in a teenager.

  20. High-efficiency l-lactic acid production by Rhizopus oryzae using a novel modified one-step fermentation strategy.

    PubMed

    Fu, Yong-Qian; Yin, Long-Fei; Zhu, Hua-Yue; Jiang, Ru

    2016-10-01

    In this study, lactic acid fermentation by Rhizopus oryzae was investigated using the two different fermentation strategies of one-step fermentation (OSF) and conventional fermentation (CF). Compared to CF, OSF reduced the demurrage of the production process and increased the production of lactic acid. However, the qp was significantly lower than during CF. Based on analysis of μ, qs and qp, a novel modified OSF strategy was proposed. This strategy aimed to achieve a high final concentration of lactic acid, and a high qp by R. oryzae. In this strategy, the maximum lactic acid concentration and productivity of the lactic acid production stage reached 158g/l and 5.45g/(lh), which were 177% and 366% higher, respectively, than the best results from CF. Importantly, the qp and yield did not decrease. This strategy is a convenient and economical method for l-lactic acid fermentation by R. oryzae.

  1. SMA-SH: Modified Styrene-Maleic Acid Copolymer for Functionalization of Lipid Nanodiscs.

    PubMed

    Lindhoud, Simon; Carvalho, Vanessa; Pronk, Joachim W; Aubin-Tam, Marie-Eve

    2016-04-11

    Challenges in purification and subsequent functionalization of membrane proteins often complicate their biochemical and biophysical characterization. Purification of membrane proteins generally involves replacing the lipids surrounding the protein with detergent molecules, which can affect protein structure and function. Recently, it was shown that styrene-maleic acid copolymers (SMA) can dissolve integral membrane proteins from biological membranes into nanosized discs. Within these nanoparticles, proteins are embedded in a patch of their native lipid bilayer that is stabilized in solution by the amphipathic polymer that wraps the disc like a bracelet. This approach for detergent-free purification of membrane proteins has the potential to greatly simplify purification but does not facilitate conjugation of functional compounds to the membrane proteins. Often, such functionalization involves laborious preparation of protein variants and optimization of labeling procedures to ensure only minimal perturbation of the protein. Here, we present a strategy that circumvents several of these complications through modifying SMA by grafting the polymer with cysteamine. The reaction results in SMA that has solvent-exposed sulfhydrils (SMA-SH) and allows tuning of the coverage with SH groups. Size exclusion chromatography, dynamic light scattering, and transmission electron microscopy demonstrate that SMA-SH dissolves lipid bilayer membranes into lipid nanodiscs, just like SMA. In addition, we demonstrate that, just like SMA, SMA-SH solubilizes proteoliposomes into protein-loaded nanodiscs. We covalently modify SMA-SH-lipid nanodiscs using thiol-reactive derivatives of Alexa Fluor 488 and biotin. Thus, SMA-SH promises to simultaneously tackle challenges in purification and functionalization of membrane proteins. PMID:26974006

  2. Simultaneous electroanalysis of dopamine and ascorbic acid using poly (N,N-dimethylaniline)-modified electrodes.

    PubMed

    Roy, Protiva Rani; Okajima, Takeyoshi; Ohsaka, Takeo

    2003-04-01

    Glassy carbon (GC) electrode is modified with an electropolymerized film of N,N-dimethylaniline (DMA). This polymer (PDMA) film-coated GC electrode is used to electrochemically detect dopamine (DA) in the presence of ascorbic acid (AA). Polymer film has the positive charge in its backbone, and in neutral solution DA exists as the positively charged species whereas AA exists as the negatively charged one. In cyclic voltammetric measurements, favorable ionic interaction (i.e., electrostatic attraction) between AA and PDMA film causes a large negative shift of the oxidation potential for AA compared to that at the bare electrode. Oxidation potential for DA is positively shifted due to the electrostatic repulsion. The PDMA film shows hydrophobicity by incorporating uncharged hydroquinone molecule within the film. DA is also incorporated into the film due to hydrophobic attraction even though DA has a positive charge. The responses of DA and AA at polymer-modified electrodes largely change with the concentration of the monomer (i.e., 0.2, 0.1 and 0.05 M DMA) used in electropolymerization and thus with the film thickness. Hydrophobicity of the polymer film shows great influence on the voltammetric responses of both DA and AA. In square wave voltammetric measurements, the PDMA film-coated electrode can separate the DA and AA oxidation potentials by about 300 mV and can detect DA at its low concentration (e.g., 0.2 microM) in the presence of 1000 times higher concentration of AA, which is close to the physiological level. AA oxidizes at more negative potential than DA. The electrode response is not affected by the oxidized product of AA. So unlike the bare electrode, the fouling effect as well as the catalytic oxidation of AA by the oxidized form of DA are eliminated at the PDMA film-coated GC electrode. The electrode exhibits the stable and sensitive response to DA.

  3. Phenolics in the Bran of Waxy Wheat and Triticale Lines

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The present study was designed to determine total phenolic acid contents (TPC) and compositions of bran from newly developed near-isogenic waxy wheat and triticale translocation lines. Two sets of near-isogenic waxy wheats, Svevo (durum) and N11 (bread wheat), consisting of partial and waxy null li...

  4. Comparison of seizure reduction and serum fatty acid levels after receiving the ketogenic and modified Atkins diet.

    PubMed

    Porta, Natacha; Vallée, Louis; Boutry, Elisabeth; Fontaine, Monique; Dessein, Anne-Frédérique; Joriot, Sylvie; Cuisset, Jean-Marie; Cuvellier, Jean-Christophe; Auvin, Stéphane

    2009-06-01

    The ketogenic diet (KD) and the modified Atkins diet are effective therapies for intractable epilepsy. We compared retrospectively the KD and modified Atkins diet in 27 children and also assessed serum long chain fatty acid profiles. After 3 months, using an intent-to-treat analysis, the KD was more successful, with >50% seizure reduction in 11/17 (65%) vs. 2/10 (20%) with the modified Atkins diet, p=0.03. After 6 months, however, the difference was no longer significant: 7/17 (41%) vs. 2/10 (20%) (p=0.24). We observed a preventive effect of both diets on the occurrence of status epilepticus. After 1 and 3 months of either diet, responders experienced a significant decrease in serum arachidonic acid concentration compared to non-responders. The KD and modified Atkins diet led to seizure reduction in this small pilot series, with slightly better results after 3 months with the KD, but not after 6 months. The decrease of serum arachidonic acid levels might be involved in the anticonvulsive effects of KD or modified Atkins diet.

  5. Standardized Ileal Amino Acid Digestibility of Corn, Corn Distillers' Dried Grains with Solubles, Wheat Middlings, and Bakery By-Products in Broilers and Laying Hens.

    PubMed

    Adedokun, S A; Jaynes, P; Payne, R L; Applegate, T J

    2015-10-01

    Standardized ileal amino acid digestibility (SIAAD) of 5 samples of corn distillers dried grain with solubles (DDGS), 5 samples of bakery by-products (BBP), 3 samples of corn, and 1 sample of wheat middlings (WM) were evaluated in broilers and laying hens. Diets containing each of the 14 feed ingredients were evaluated in 21 day-old broiler chickens. The DDGS and BBP containing diets were fed to 30-week-old laying hens, while corn and wheat middling were evaluated in 50-week-old laying hens. All the diets were semi-purified with each feed ingredient being the only source of amino acid (AA). To obtain SIAAD values, apparent ileal AA digestibility was corrected for basal ileal endogenous AA losses using values generated from broilers and laying hens fed a nitrogen-free diet. Ileal crude protein digestibility for the 5 DDGS samples was higher (P < 0.05) in broilers than in laying hens. Broilers had higher SIAAD for DDGS 2, 3, 4, and 5 while there was no difference for DDGS 1 except for 4 AA where broilers had higher (P < 0.05) SIAAD values. Standardized ileal AA digestibility values for broilers were higher (P < 0.05) for BBP 1 and 4. Ileal CP digestibility for corn 1 was higher (P < 0.05) for broilers compared to laying hens, and SIAAD values for the 16 AA (9 indispensable and 7 dispensable) evaluated in this study were higher (P < 0.05) in broilers. Broilers had higher (P < 0.05) SIAAD values for 4 (histidine, leucine, phenylalanine, and valine) and 6 (histidine, leucine, methionine, phenylalanine, threonine, and valine) indispensable and 3 (cysteine, glutamic acid, and proline) and 4 (cysteine, glutamic acid, proline, and serine) dispensable AA for corn 2 and corn 3, respectively. No difference in SIAAD between broilers and laying hens was observed for WM. Results from this study confirm that high variability in digestibility exists between different samples of DDGS. Differences in SIAAD between broilers and laying hens were observed in some samples of

  6. Standardized Ileal Amino Acid Digestibility of Corn, Corn Distillers' Dried Grains with Solubles, Wheat Middlings, and Bakery By-Products in Broilers and Laying Hens.

    PubMed

    Adedokun, S A; Jaynes, P; Payne, R L; Applegate, T J

    2015-10-01

    Standardized ileal amino acid digestibility (SIAAD) of 5 samples of corn distillers dried grain with solubles (DDGS), 5 samples of bakery by-products (BBP), 3 samples of corn, and 1 sample of wheat middlings (WM) were evaluated in broilers and laying hens. Diets containing each of the 14 feed ingredients were evaluated in 21 day-old broiler chickens. The DDGS and BBP containing diets were fed to 30-week-old laying hens, while corn and wheat middling were evaluated in 50-week-old laying hens. All the diets were semi-purified with each feed ingredient being the only source of amino acid (AA). To obtain SIAAD values, apparent ileal AA digestibility was corrected for basal ileal endogenous AA losses using values generated from broilers and laying hens fed a nitrogen-free diet. Ileal crude protein digestibility for the 5 DDGS samples was higher (P < 0.05) in broilers than in laying hens. Broilers had higher SIAAD for DDGS 2, 3, 4, and 5 while there was no difference for DDGS 1 except for 4 AA where broilers had higher (P < 0.05) SIAAD values. Standardized ileal AA digestibility values for broilers were higher (P < 0.05) for BBP 1 and 4. Ileal CP digestibility for corn 1 was higher (P < 0.05) for broilers compared to laying hens, and SIAAD values for the 16 AA (9 indispensable and 7 dispensable) evaluated in this study were higher (P < 0.05) in broilers. Broilers had higher (P < 0.05) SIAAD values for 4 (histidine, leucine, phenylalanine, and valine) and 6 (histidine, leucine, methionine, phenylalanine, threonine, and valine) indispensable and 3 (cysteine, glutamic acid, and proline) and 4 (cysteine, glutamic acid, proline, and serine) dispensable AA for corn 2 and corn 3, respectively. No difference in SIAAD between broilers and laying hens was observed for WM. Results from this study confirm that high variability in digestibility exists between different samples of DDGS. Differences in SIAAD between broilers and laying hens were observed in some samples of

  7. Chromate adsorption on acid-treated and amines-modified clay

    NASA Astrophysics Data System (ADS)

    Hajjaji, M.; Beraa, A.

    2015-03-01

    Acid-treated montmorillonite-rich clay and amines (methylamine, morpholine, and aniline)-modified clay adsorbents were investigated and their abilities to remove chromate from aqueous solution were studied. For the later purpose, kinetic studies were carried out under different operating conditions (chromate concentration, adsorbent content, and temperature), and adsorption isotherm measurements were performed. It was found that the kinetic of adsorption was fast and the data followed the pseudo-second rate equation. The rate of adsorption was controlled by the intra-particle diffusion and mass transfer through the liquid film, and the relative importance of these limiting steps depended on the operating conditions. Chromate adsorption was an endothermic process and took place spontaneously by physisorption. The free energy at 25 ≤ T ≤ 40 °C varied from -1.5 to -46 kJ/mol. Adsorption isotherms of Na+-saturated clay (AN), acid-treated clay (AA), and methylamine-clay and morpholine-clay (A-Me, A-Mo) were type V, whereas those of aniline-clay (A-An) were type III. The estimated maximum uptakes were 105, 29, 15, 11, and 10 mmol/kg for A-An, AN, A-Mo, AA, and A-Me, respectively. The mechanism of chromate adsorption was discussed based on the shape of the isotherms. Considering for instance the most efficient absorbent (A-An), the isotherm followed the Freundlich equation and hydrogen chromate (the main stable form at working pH) adsorbed to solid particles once aniline species were entirely desorbed.

  8. Ulleungamides A and B, Modified α,β-Dehydropipecolic Acid Containing Cyclic Depsipeptides from Streptomyces sp. KCB13F003.

    PubMed

    Son, Sangkeun; Ko, Sung-Kyun; Jang, Mina; Lee, Jae Kyoung; Ryoo, In-Ja; Lee, Jung-Sook; Lee, Kyung Ho; Soung, Nak-Kyun; Oh, Hyuncheol; Hong, Young-Soo; Kim, Bo Yeon; Jang, Jae-Hyuk; Ahn, Jong Seog

    2015-08-21

    Two novel cyclic depsipeptides, ulleungamides A (1) and B (2), were isolated from cultures of terrestrial Streptomyces sp. Their structures were determined by analyses of spectroscopic data and various chemical transformations, including modified Mosher's method, advanced Marfey's method, PGME, GITC derivatizations, and Snatzke's method. Ulleungamides were determined to be a new class of peptides bearing unprecedented units, such as 5-hydroxy-6-methyl-2,3-dehydropipecolic acid, 4,5-dihydroxy-6-methyl-2,3-dehydropipecolic acid, and amino-linked 2-isopropylsuccinic acid. Ulleungamide A displayed growth inhibitory activity against Staphylococcus aureus and Salmonella typhimurium without cytotoxicity. PMID:26262430

  9. Phenylboronic acid modified solid-phase extraction column: Preparation, characterization, and application to the analysis of amino acids in sepia capsule by removing the maltose.

    PubMed

    Guo, Mengzhe; Yin, Dengyang; Han, Jie; Zhang, Liyan; Li, Xiao; He, Dandan; Du, Yan; Tang, Daoquan

    2016-09-01

    Maltose, a common auxiliary material of pharmaceutical preparation, may disturb the analysis of total amino acids in sepia capsule by aldolization. Therefore, it is necessary to remove the maltose through a convenient method. In this work, a phenylboronic acid modified solid-phase extraction column has been synthesized and used to remove the maltose. The materials were synthesized by one step "thiol-ene" reaction and the parameters of the column such as absorption capacity, recovery, and absorption specificity have been investigated. The results showed the column (0.5 cm of length × 0.5 cm of inner diameter) can absorb 4.6 mg maltose with a linear absorption and absorption specificity. Then this technique was applied in the quantification of amino acids in sepia capsule. After the optimization of the method, four kinds of amino acids, which were the most abundant, were quantified by high-performance liquid chromatography with diode array detection. The amounts of the four kinds of amino acids are 1.5∼2 times more than that without the treatment of solid-phase extraction column, which almost overcomes the influence of the maltose. All the results indicate that the phenylboronic acid modified solid-phase extraction column can successfully help to accurately quantify the total amino acids in sepia capsule.

  10. Use of fungal proteases and selected sourdough lactic acid bacteria for making wheat bread with an intermediate content of gluten.

    PubMed

    Rizzello, Carlo Giuseppe; Curiel, José Antonio; Nionelli, Luana; Vincentini, Olimpia; Di Cagno, Raffaella; Silano, Marco; Gobbetti, Marco; Coda, Rossana

    2014-02-01

    This study was aimed at combining the highest degradation of gluten during wheat flour fermentation with good structural and sensory features of the related bread. As estimated by R5-ELISA, the degree of degradation of immune reactive gluten was ca. 28%. Two-dimensional electrophoresis and RP-FPLC analyses showed marked variations of the protein fractions compared to the untreated flour. The comparison was also extended to in vitro effect of the peptic/tryptic-digests towards K562 and T84 cells. The flour with the intermediate content of gluten (ICG) was used for bread making, and compared to whole gluten (WG) bread. The chemical, structural and sensory features of the ICG bread approached those of the bread made with WG flour. The protein digestibility of the ICG bread was higher than that from WG flour. Also the nutritional quality, as estimated by different indexes, was the highest for ICG bread.

  11. Synthesis and Protein Incorporation of Azido-Modified Unnatural Amino Acids

    PubMed Central

    Tookmanian, Elise M.; Fenlon, Edward E.; Brewer, Scott H.

    2015-01-01

    Two new azidophenylalanine residues (3 and 4) have been synthesized and, in combination with 4-azido-L-phenylalanine (1) and 4-azidomethyl-L-phenylalanine (2), form a series of unnatural amino acids (UAAs) containing the azide vibrational reporter at varying distances from the aromatic ring of phenylalanine. These UAAs were designed to probe protein hydration with high spatial resolution by utilizing the large extinction coefficient and environmental sensitivity of the azide asymmetric stretch vibration. The sensitivity of the azide reporters was investigated in solvents that mimic distinct local protein environments. Three of the four azido-modified phenylalanine residues were successfully genetically incorporated into a surface site in superfolder green fluorescent protein (sfGFP) utilizing an engineered, orthogonal aminoacyl-tRNA synthetase in response to an amber codon with high efficiency and fidelity. SDS-PAGE and ESI-Q-TOF mass analysis verified the site-specific incorporation of these UAAs. The observed azide asymmetric stretch in the linear IR spectra of these UAAs incorporated into sfGFP indicated that the azide groups were hydrated in the protein. PMID:26478813

  12. Synthesis of heterocycle-modified betulinic acid derivatives as antitumor agents.

    PubMed

    Cui, Hai-Wei; He, Yuan; Wang, Jinhua; Gao, Wei; Liu, Ting; Qin, Min; Wang, Xue; Gao, Cheng; Wang, Yan; Liu, Ming-Yao; Yi, Zhengfang; Qiu, Wen-Wei

    2015-05-01

    A series of novel heterocycle-modified betulinic acid (BA) derivatives were synthesized and investigated for their activity against the growth of eight non-drug resistant and one multidrug-resistant tumor cell line using a sulforhodamine B (SRB) assay. The most active compound 17 showed an average IC50 1.19 μM, which was about 20 times more potent than the lead compound BA. It is amazing that for most synthetic saturated N-heterocycle derivatives, MCF-7/ADR was the most sensitive tumor cells, especially 17 showed the most potent antitumor activity (IC50 = 0.33 μM) on this multidrug-resistant tumor cell line, that was 117 times more potent than BA. Most of the tested compounds displayed less toxic on human fibroblasts (HAF) in comparison with the tumor cell lines. The cytometry and transwell migration assays were used to test the ability of 17 to induce apoptosis and inhibit metastasis on tumor cell lines respectively.

  13. Silymarin-Loaded Nanoparticles Based on Stearic Acid-Modified Bletilla striata Polysaccharide for Hepatic Targeting.

    PubMed

    Ma, Yanni; He, Shaolong; Ma, Xueqin; Hong, Tongtong; Li, Zhifang; Park, Kinam; Wang, Wenping

    2016-01-01

    Silymarin has been widely used as a hepatoprotective drug in the treatment of various liver diseases, yet its effectiveness is affected by its poor water solubility and low bioavailability after oral administration, and there is a need for the development of intravenous products, especially for liver-targeting purposes. In this study, silymarin was encapsulated in self-assembled nanoparticles of Bletilla striata polysaccharide (BSP) conjugates modified with stearic acid and the physicochemical properties of the obtained nanoparticles were characterized. The silymarin-loaded micelles appeared as spherical particles with a mean diameter of 200 nm under TEM. The encapsulation of drug molecules was confirmed by DSC thermograms and XRD diffractograms, respectively. The nanoparticles exhibited a sustained-release profile for nearly 1 week with no obvious initial burst. Compared to drug solutions, the drug-loaded nanoparticles showed a lower viability and higher uptake intensity on HepG2 cell lines. After intravenous administration of nanoparticle formulation for 30 min to mice, the liver became the most significant organ enriched with the fluorescent probe. These results suggest that BSP derivative nanoparticles possess hepatic targeting capability and are promising nanocarriers for delivering silymarin to the liver.

  14. Production of resistant starch by extrusion cooking of acid-modified normal-maize starch.

    PubMed

    Hasjim, Jovin; Jane, Jay-Lin

    2009-09-01

    The objective of this study was to utilize extrusion cooking and hydrothermal treatment to produce resistant starch (RS) as an economical alternative to a batch-cooking process. A hydrothermal treatment (110 degrees C, 3 d) of batch-cooked and extruded starch samples facilitated propagation of heat-stable starch crystallites and increased the RS contents from 2.1% to 7.7% up to 17.4% determined using AOAC Method 991.43 for total dietary fiber. When starch samples were batch cooked and hydrothermally treated at a moisture content below 70%, acid-modified normal-maize starch (AMMS) produced a greater RS content than did native normal-maize starch (NMS). This was attributed to the partially hydrolyzed, smaller molecules in the AMMS, which had greater mobility and freedom than the larger molecules in the NMS. The RS contents of the batch-cooked and extruded AMMS products after the hydrothermal treatment were similar. A freezing treatment of the AMMS samples at -20 degrees C prior to the hydrothermal treatment did not increase the RS content. The DSC thermograms and the X-ray diffractograms showed that retrograded amylose and crystalline starch-lipid complex, which had melting temperatures above 100 degrees C, accounted for the RS contents.

  15. Electrochemical biosensing platform using hydrogel prepared from ferrocene modified amino acid as highly efficient immobilization matrix.

    PubMed

    Qu, Fengli; Zhang, Yi; Rasooly, Avraham; Yang, Minghui

    2014-01-21

    To increase the loading of glucose oxidase (GOx) and simplify glucose biosensor fabrication, hydrogel prepared from ferrocene (Fc) modified amino acid phenylalanine (Phe, F) was utilized for the incorporation of GOx. The synthesized hydrogel displays good biocompatibility and contains a significant number of Fc moieties, which can be considered as an ideal matrix to immobilize enzymes for the preparation of mediator-based biosensors. The hydrogel was studied by scanning electron microscopy, which indicated that it was composed of nanofibers with a diameter of around 50-100 nm and length extended to 1 mm. With the addition of GOx into the hydrogel and by directly dropping the resulting biocomposite onto the electrode surface, a glucose biosensor, that displays good performance due to improved enzyme loading and efficient electron transfer, can be simply constructed. The favorable network structure and good biocompatibility of the hydrogel could effectively avoid enzyme leakage and maintain the bioactivity of the enzymes, which resulted in good stability of the biosensor. The biosensor was utilized for the detection of glucose in blood samples with results comparable to those obtained from the hospital. The hydrogel as a functional component of an amperometric biosensor has implications for future development of biosensors and for clinical applications. PMID:24383679

  16. Sulfoacetic acid modifying poly(vinyl alcohol) hydrogel and its electroresponsive behavior under DC electric field

    NASA Astrophysics Data System (ADS)

    Xiang, Yu; Liu, Genqi; Zhang, Cheng; Liao, Jiae

    2013-01-01

    A strong electrolyte hydrogel was prepared by modifying poly (vinyl alcohol) hydrogel with sulfoacetic acid (SA-PVA). Its swelling properties, mechanical properties, and electroresponsive behavior in Na2SO4 solutions were studied. The results indicated that the water take-up ability of the hydrogel decreased with the increasing ionic strength of Na2SO4 solution. The Young’s modulus, elongation at break and tensile strength of the hydrogel swollen in deionized water are 1.247 MPa, 187% and 2.2 MPa, respectively. The hydrogel swollen in a Na2SO4 solution bent towards the cathode under non-contact dc electric fields, and its bending speed and equilibrium strain increased with increasing applied voltage. There is a critical ionic strength of 0.03 at which the maximum equilibrium strain of the hydrogel occurs. Also the bending behavior of hydrogel was not affected by the pH changes. By altering the direction of the applied potential cyclically, the hydrogel exhibited good reversible bending behavior. On this basis, a gel-worm was designed. Under a cyclically varying electric field (the period was 8 s, and the voltage ranged from -10 to 10 V), the walking speed was up to 15 cm min-1 in Na2SO4 solution with an ionic strength of 0.03.

  17. Styrene-butadiene rubber/halloysite nanotubes nanocomposites modified by methacrylic acid

    NASA Astrophysics Data System (ADS)

    Guo, Baochun; Lei, Yanda; Chen, Feng; Liu, Xiaoliang; Du, Mingliang; Jia, Demin

    2008-12-01

    Methacrylic acid (MAA) was used to improve the performance of styrene-butadiene rubber (SBR)/halloysite nanotubes (HNTs) nanocomposites by direct blending. The detailed interaction mechanisms of MAA and the in situ formed zinc methacrylate (ZDMA) were revealed by X-ray diffraction (XRD), surface area and porosity analysis, X-ray photoelectron spectroscopy (XPS) together with crosslink density determination. The strong interfacial bonding between HNTs and rubber matrix is resulted through ZDMA and MAA intermediated linkages. ZDMA connects SBR and HNTs via grafting/complexation mechanism. MAA bonds SBR and HNTs through grafting/hydrogen bonding mechanism. Significantly improved dispersion of HNTs in virtue of the interactions between HNTs and MAA or ZDMA was achieved. Effects of MAA content on the vulcanization behavior, morphology and mechanical properties of the nanocomposites were investigated. Promising mechanical properties of MAA modified SBR/HNTs nanocomposites were obtained. The changes in vulcanization behavior, mechanical properties and morphology were correlated with the interactions between HNTs and MAA or ZDMA and the largely improved dispersion of HNTs.

  18. Styrene-butadiene rubber/halloysite nanotubes nanocomposites modified by sorbic acid

    NASA Astrophysics Data System (ADS)

    Guo, Baochun; Chen, Feng; Lei, Yanda; Liu, Xiaoliang; Wan, Jingjing; Jia, Demin

    2009-05-01

    Sorbic acid (SA) was used to improve the performance of styrene-butadiene rubber (SBR)/halloysite nanotubes (HNTs) nanocomposites by direct blending. The detailed mechanisms for the largely improved performance were studied by X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), differential scanning calorimetry (DSC), porosity analysis and crosslink density determination. The strong interfacial bonding between HNTs and rubber matrix is resulted through SA intermediated linkages. SA bonds SBR and HNTs through grafting copolymerization/hydrogen bonding mechanism. Significantly improved dispersion of HNTs in virtue of the interactions between HNTs and SA was achieved. Formation of zinc disorbate (ZDS) was revealed during the vulcanization of the composites. However, in the present systems, the contribution of ZDS to the reinforcement was limited. Effects of SA content on the vulcanization behavior, morphology and mechanical properties of the nanocomposites were investigated. Promising mechanical properties of SA modified SBR/HNTs nanocomposites were obtained. The changes in vulcanization behavior, mechanical properties and morphology were correlated with the interactions between HNTs and SA and the largely improved dispersion of HNTs.

  19. Microencapsulation of stearidonic acid soybean oil in Maillard reaction-modified complex coacervates.

    PubMed

    Ifeduba, Ebenezer A; Akoh, Casimir C

    2016-05-15

    The antioxidant capacity of Maillard reaction (MR)-modified gelatin (GE)-gum arabic (GA) coacervates was optimized to produce microcapsules with superior oxidative stability compared to the unmodified control. MR was used to crosslink GE and GA, with or without maltodextrin (MD), to produce anti-oxidative Maillard reaction products (MRP) which was used to encapsulate stearidonic acid soybean oil (SDASO) by complex coacervation. Biopolymer blends (GE-GA [1:1, w/w] or GE-GA-MD [2:2:1, w/w/w]) were crosslinked by dry-heating at 80°C for 4, 8, or 16h. Relationships between the extent of browning, Trolox equivalent antioxidant capacity (TEAC), and the total oxidation (TOTOX) of encapsulated SDASO were fitted to quadratic models. The [GE-GA-MD] blends exhibited higher browning rates and TEAC values than corresponding [GE-GA] blends. Depending on the type of biopolymer blend and dry-heating time, TOTOX values of SDASO in MRP-derived microcapsules were 29-87% lower than that of the non-crosslinked control after 30 days of storage.

  20. Interaction of immunoglobulin G with N,N,N',N'-ethylenediaminetetramethylenephosphonic acid-modified zirconia.

    PubMed

    Subramanian, Anuradha; Sarkar, Sabyasachi

    2003-03-01

    Zirconia beads (25-38 microm in diameter) were modified with N,N,N'.N'-ethylenediaminetetramethylenephosphonic acid to generate a pseudo-biospecific support, r_PEZ. To better understand the force of interaction between the IgG and the r_PEZ, the equilibrium dissociation constant (Kd) was determined by static binding isotherms, as a function of temperature and by frontal analysis at different linear velocities. Temperature had no significant impact on the maximum static binding capacity (Q(max)) and the equilibrium-binding constant (Kd), whereas pH and the salt concentration had a noticeable impact on both Q(max) and Kd values. Q(max) was found to be in the range of 55-65 mg IgG per ml of beads and unaffected by temperature. The maximum dynamic binding capacity (Qx) was found to be in the range of 20-12 mg IgG per ml of beads. The adsorption rate constant (ka) was determined by a split-peak approach to be between 982 and 32421 mol(-1) s(-1) depending on the linear velocity. Adsorption rate of IgG on r_PEZ was studied as a function of both feed concentration and linear velocity. The standard enthalpy and entropy values were estimated for the interaction of IgG with this novel support. The binding constants were also determined by modeling the batch protein-uptake data. PMID:12641289

  1. Polyacrylic acid modified upconversion nanoparticles for simultaneous pH-triggered drug delivery and release imaging.

    PubMed

    Jia, Xuekun; Yin, Jinjin; He, Dinggeng; He, Xiaoxiao; Wang, Kemin; Chen, Mian; Li, Yuhong

    2013-12-01

    A poly(acrylicacid)-modified NaYF4:Yb, Er upconversion nanoparticles (PAA-UCNPs) with dual functions of drug delivery and release imaging have been successfully developed. The PAA polymer coated on the surface of UCNPs serve as a pH-sensitive nanovalve for loading drug molecules via electrostatic interaction. The drug-loading efficiency of the PAA-UCNPs was investigated by using doxorubicin hydrochloride (DOX) as a model anticancer drug to evaluate their potential as a delivery system. Results showed loading and releasing of DOX from PAA-UCNPs were controlled by varying pH, with high encapsulation rate at weak alkaline conditions and an increased drug dissociation rate in acidic environment, which is favorable for construct a pH-responsive controlled drug delivery system. The in vitro cytotoxicity test using HeLa cell line indicated that the DOX loaded PAA-UCNPs (DOX@PAA-UCNPs) were distinctly cytotoxic to HeLa cells, while the PAA-UCNPs were highly biocompatible and suitable to use as drug carriers. Furthermore, the upconversion fluorescence resonance energy transfer (UFRET) imaging through the two-photon laser scanning microscopy (TLSM) revealed the time course of intracellular delivery of DOX from DOX@PAA-UCNPs. Thus, PAA-UCNPs are effective for constructing pH-responsive controlled drug delivery systems for multi-functional cancer therapy and imaging. PMID:24266261

  2. Hyaluronic acid modified mesoporous silica nanoparticles for targeted drug delivery to CD44-overexpressing cancer cells

    NASA Astrophysics Data System (ADS)

    Yu, Meihua; Jambhrunkar, Siddharth; Thorn, Peter; Chen, Jiezhong; Gu, Wenyi; Yu, Chengzhong

    2012-12-01

    In this paper, a targeted drug delivery system has been developed based on hyaluronic acid (HA) modified mesoporous silica nanoparticles (MSNs). HA-MSNs possess a specific affinity to CD44 over-expressed on the surface of a specific cancer cell line, HCT-116 (human colon cancer cells). The cellular uptake performance of fluorescently labelled MSNs with and without HA modification has been evaluated by confocal microscopy and fluorescence-activated cell sorter (FACS) analysis. Compared to bare MSNs, HA-MSNs exhibit a higher cellular uptake via HA receptor mediated endocytosis. An anticancer drug, doxorubicin hydrochloride (Dox), has been loaded into MSNs and HA-MSNs as drug delivery vehicles. Dox loaded HA-MSNs show greater cytotoxicity to HCT-116 cells than free Dox and Dox-MSNs due to the enhanced cell internalization behavior of HA-MSNs. It is expected that HA-MSNs have a great potential in targeted delivery of anticancer drugs to CD44 over-expressing tumors.

  3. Characterization and immobilization of trypsin on tannic acid modified Fe3O4 nanoparticles.

    PubMed

    Atacan, Keziban; Özacar, Mahmut

    2015-04-01

    Fe3O4 nanoparticles (NPs) were synthesized by co-precipitating Fe2+ and Fe3+ in an ammonia solution. Fe3O4 NPs functionalized with tannic acid were prepared. After functionalization process, trypsin enzyme was immobilized on these Fe3O4 NPs. The influence of pH, temperature, thermal stability, storage time stability and reusability on non-covalent immobilization was studied. The properties of Fe3O4 and its modified forms were examined by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), thermal gravimetric analysis (TGA), UV-vis spectrometer (UV) and X-ray diffraction (XRD), magnetization and zeta potential measurements. The immobilized enzyme was slightly more stable than the free enzyme at 45°C. According to the results, the activity of immobilized trypsin was preserved 55% at 45°C after 2 h and 90% after 120 days storage. In addition, the activity of the immobilized trypsin was preserved 40% of its initial activity after eight times of successive reuse. PMID:25686792

  4. Crystalline and structural properties of acid-modified lotus rhizome C-type starch.

    PubMed

    Cai, Jinwen; Cai, Canhui; Man, Jianmin; Yang, Yang; Zhang, Fengmin; Wei, Cunxu

    2014-02-15

    The crystalline and structural properties of acid-modified C-type starch from lotus rhizomes were investigated using a combination of techniques. The degradation of granule during hydrolysis began from the end distant from the hilum and then propagated into the center of granule, accompanied by loss of birefringence. The crystallinity changed from C-type to A-type via CA-type during hydrolysis. At the early stage of hydrolysis, the amylose content substantially reduced, the peak and conclusion gelatinization temperatures increased, and the enthalpy decreased. During hydrolysis, the double helix content gradually increased and the amorphous component decreased, the lamellar peak intensity firstly increased and then decreased accompanied by hydrolysis of amorphous and crystalline regions. This study elucidated that B-type allomorph was mainly arranged in the distal region of eccentric hilum, A-type allomorph was mainly located in the periphery of hilum end, and the center of granule was a mixed distribution of A- and B-type allomorphs. PMID:24507349

  5. Crystalline and structural properties of acid-modified lotus rhizome C-type starch.

    PubMed

    Cai, Jinwen; Cai, Canhui; Man, Jianmin; Yang, Yang; Zhang, Fengmin; Wei, Cunxu

    2014-02-15

    The crystalline and structural properties of acid-modified C-type starch from lotus rhizomes were investigated using a combination of techniques. The degradation of granule during hydrolysis began from the end distant from the hilum and then propagated into the center of granule, accompanied by loss of birefringence. The crystallinity changed from C-type to A-type via CA-type during hydrolysis. At the early stage of hydrolysis, the amylose content substantially reduced, the peak and conclusion gelatinization temperatures increased, and the enthalpy decreased. During hydrolysis, the double helix content gradually increased and the amorphous component decreased, the lamellar peak intensity firstly increased and then decreased accompanied by hydrolysis of amorphous and crystalline regions. This study elucidated that B-type allomorph was mainly arranged in the distal region of eccentric hilum, A-type allomorph was mainly located in the periphery of hilum end, and the center of granule was a mixed distribution of A- and B-type allomorphs.

  6. Phenylboronic acid modified silver nanoparticles for colorimetric dynamic analysis of glucose.

    PubMed

    Cao, Ke; Jiang, Xiaomei; Yan, Suting; Zhang, Laiying; Wu, Weitai

    2014-02-15

    The development of advanced nanostructures that allow dynamic quantification of glucose level can contribute to tight glucose control in diabetes management and other medical/biological fields. In this paper, we demonstrated that the assemblies of the 5-amino-2-fluorophenylboronic acid modified silver nanoparticles (FPBA-AgNPs) can be employed for highly modulating, sensitive, and selective colorimetric sensing of glucose over a physiologically important concentration range of 0-20mM at a physiological pH of 7.4. The glucose-modulated assembly of the FPBA-AgNPs occurred by the regulable formation of interparticle linkages via the bridged binding of 1,2-cis-diols and 5,6-cis-diols (for furanose form; or 4,6-cis-diols for pyranose form), respectively, of a glucose molecule to two FPBA-AgNPs. The detection limit was 89.0 μM. The mean error of glucose detection in a macro-bio-system, blood serum of adult, was smaller than 10%. Furthermore, we show that the glucose level variations associated with a model biological reaction process can be monitored by using the FPBA-AgNPs, whilst with the reaction mechanism remaining nearly unchanged. PMID:24055932

  7. Risk assessment of genetically modified lactic acid bacteria using the concept of substantial equivalence.

    PubMed

    LeBlanc, Jean Guy; Van Sinderen, Douwe; Hugenholtz, Jeroen; Piard, Jean-Christophe; Sesma, Fernando; de Giori, Graciela Savoy

    2010-12-01

    The use of food-grade microorganisms such as lactic acid bacteria (LAB) is one of the most promising methods for delivering health promoting compounds. Since it is not always possible to obtain strains that have the ability to produce specific compounds naturally or that produce them in sufficient quantities to obtain physiological responses, genetic modifications can be performed to improve their output. The objective of this study was to evaluate if previously studied genetically modified LAB (GM-LAB), with proven in vivo beneficial effects, are just as safe as the progenitor strain from which they were derived. Mice received an elevated concentration of different GM-LAB or the native parental strain from which they were derived during a prolonged period of time, and different health parameters were evaluated. Similar growth rates, hematological values, and other physiological parameters were obtained in the animals that received the GM-LAB compared to those that were fed with the native strain. These results demonstrate that the GM-LAB used in this study are just as safe as the native strains from which they were derived and thus merit further studies to include them into the food chain.

  8. Surface properties and early murine pre-osteoblastic cell responses of phosphoric acid modified titanium surface

    PubMed Central

    Osathanon, Thanaphum; Sawangmake, Chenphop; Ruangchainicom, Nanticha; Wutikornwipak, Pavitra; Kantukiti, Panisa; Nowwarote, Nunthawan; Pavasant, Prasit

    2015-01-01

    Aims The present study investigated the surface properties and murine pre-osteoblast cell (MC3T3-E1) responses of phosphoric acid (H3PO4) treated commercially pure titanium. Methods Titanium discs were treated with various concentration of H3PO4 (5%, 10%, and 20%; v/v) at 90 °C for 30 min. Surface properties were evaluated by profilometer, contact angle meter, and scanning electron microscopy (SEM) with energy dispersive X-rays. MC3T3-E1 attachment and spreading were evaluated by SEM and phalloidin immunohistochemistry staining. Results Surface roughness and wettability were not statistically difference among all experimental and control groups. Phosphate and oxygen were detected on H3PO4 treated surfaces. At 20 min, cell attachment was significantly higher in 10% and 20% H3PO4 treated groups compared to the control. Cells exhibited orientated-cytoskeleton fibers on 20% H3PO4 modified titanium surface. Though, there was no difference in cell spreading stage among all treatment groups. Conclusion H3PO4 treatment on titanium may influence early cell response, particularly on attachment and spreading. PMID:26937362

  9. Amperometric sensing of ascorbic acid using a disposable screen-printed electrode modified with electrografted o-aminophenol film.

    PubMed

    Nassef, Hossam M; Civit, Laia; Fragoso, Alex; O'Sullivan, Ciara K

    2008-12-01

    Electrode modification by electrochemical reduction of diazonium salts of different aryl derivatives is useful for catalytic, analytical and biotechnological applications. A simple and sensitive method for the electrocatalytic detection of ascorbic acid using disposable screen-printed carbon electrodes modified with an electrografted o-aminophenol film, via the electrochemical reduction of its in situ prepared diazonium salts in aqueous solution, is presented. The performance of two commercial SPEs as substrates for grafting of diazonium films has been compared and the grafting process optimized with respect to deposition time and diazonium salt concentration, with the modified surfaces being characterised using cyclic voltammetry. The functionalised screen-printed electrodes demonstrated an excellent electrocatalytic activity towards the oxidation of ascorbic acid shifting the overpotential from 298 and 544 mV to 160 and 244 mV, respectively vs. Ag/AgCl. DC amperometric measurements were carried out for the quantitative determination of ascorbic acid using the modified electrodes. The catalytic oxidation peak current was linearly dependent on the ascorbic acid concentration in the range of 2-20 microM, with a correlation coefficient 0.998, and a limit of detection of 0.86 microM was obtained with an excellent reproducibility (RSD% = 1.98, n = 8). The functionalised screen-printed electrodes exhibited notable surface stability, and were used as a simple and precise disposable sensor for the selective determination of ascorbic acid.

  10. Apparent digestibility of wheat bran and extruded flax in horses determined from the total collection of feces and acid-insoluble ash as an internal marker.

    PubMed

    De Marco, M; Miraglia, N; Peiretti, P G; Bergero, D

    2012-02-01

    Several studies have reported data on comparisons between two methods: the total collection of feces and the internal markers method. The aim of this study was to assess the apparent digestibility of two concentrates and to compare the apparent digestion coefficients using the total collection of feces and acid-insoluble ash (AIA) as the internal marker method. In 2009, six adult geldings aged between 3 and 11 years, with an average weight per trial of 543, 540 and 542 kg, respectively, were used to determine the apparent digestibility by means of three in vivo digestibility trials on hay, hay plus wheat bran (60 : 40) and hay plus extruded flax (80 : 20). Feces were collected over a 6-day period with a previous 14-day adaptation period. The three digestibility trials were carried out to determine the digestion coefficients of the three diets and, indirectly, of the two concentrates. The digestion coefficients of the diets were determined for the dry matter, organic matter, crude protein and gross energy, whereas the apparent digestion coefficients of the same parameters were calculated for wheat bran and extruded flax, by calculating the difference from the previous results. The data were analyzed using the Student t-test for paired samples. The digestion coefficients obtained were similar when the total collection of feces and the AIA method were used. Higher data variability, confirmed by a greater standard deviation, was observed using the AIA method to estimate the apparent digestion coefficients. It can be concluded that the use of AIA as an internal marker in digestibility trials on average leads to values similar to those obtained with the total collection of feces and can therefore be considered a less-expensive method to determine apparent digestion coefficients. Nevertheless, the total collection of feces should still be considered the best choice to determine the digestibility of some specific feedstuffs.

  11. TaCHP: a wheat zinc finger protein gene down-regulated by abscisic acid and salinity stress plays a positive role in stress tolerance.

    PubMed

    Li, Cuiling; Lv, Jian; Zhao, Xin; Ai, Xinghui; Zhu, Xinlei; Wang, Mengcheng; Zhao, Shuangyi; Xia, Guangmin

    2010-09-01

    The plant response to abiotic stresses involves both abscisic acid (ABA)-dependent and ABA-independent signaling pathways. Here we describe TaCHP, a CHP-rich (for cysteine, histidine, and proline rich) zinc finger protein family gene extracted from bread wheat (Triticum aestivum), is differentially expressed during abiotic stress between the salinity-sensitive cultivar Jinan 177 and its tolerant somatic hybrid introgression cultivar Shanrong No.3. TaCHP expressed in the roots of seedlings at the three-leaf stage, and the transcript localized within the cells of the root tip cortex and meristem. TaCHP transcript abundance was higher in Shanrong No.3 than in Jinan 177, but was reduced by the imposition of salinity or drought stress, as well as by the exogenous supply of ABA. When JN17, a salinity hypersensitive wheat cultivar, was engineered to overexpress TaCHP, its performance in the face of salinity stress was improved, and the ectopic expression of TaCHP in Arabidopsis (Arabidopsis thaliana) also improved the ability of salt tolerance. The expression level of a number of stress reporter genes (AtCBF3, AtDREB2A, AtABI2, and AtABI1) was raised in the transgenic lines in the presence of salinity stress, while that of AtMYB15, AtABA2, and AtAAO3 was reduced in its absence. The presence in the upstream region of the TaCHP open reading frame of the cis-elements ABRE, MYBRS, and MYCRS suggests that it is a component of the ABA-dependent and -independent signaling pathways involved in the plant response to abiotic stress. We suggest that TaCHP enhances stress tolerance via the promotion of CBF3 and DREB2A expression.

  12. Liver fatty acid-binding protein (L-Fabp) modifies intestinal fatty acid composition and adenoma formation in ApcMin/+ mice.

    PubMed

    Dharmarajan, Sekhar; Newberry, Elizabeth P; Montenegro, Grace; Nalbantoglu, Ilke; Davis, Victoria R; Clanahan, Michael J; Blanc, Valerie; Xie, Yan; Luo, Jianyang; Fleshman, James W; Kennedy, Susan; Davidson, Nicholas O

    2013-10-01

    Evidence suggests a relationship between dietary fat intake, obesity, and colorectal cancer, implying a role for fatty acid metabolism in intestinal tumorigenesis that is incompletely understood. Liver fatty acid-binding protein (L-Fabp), a dominant intestinal fatty acid-binding protein, regulates intestinal fatty acid trafficking and metabolism, and L-Fabp deletion attenuates diet-induced obesity. Here, we examined whether changes in intestinal fatty acid metabolism following L-Fabp deletion modify adenoma development in Apc(Min)(/+) mice. Compound L-Fabp(-/-)Apc(Min)(/+) mice were generated and fed a 10% fat diet balanced equally between saturated, monounsaturated, and polyunsaturated fat. L-Fabp(-/-)Apc(Min)(/+) mice displayed significant reductions in adenoma number and total polyp area compared with Apc(Min)(/+)controls, reflecting a significant shift in distribution toward smaller polyps. Adenomas from L-Fabp(-/-)Apc(Min)(/+) mice exhibited reductions in cellular proliferation, high-grade dysplasia, and nuclear β-catenin translocation. Intestinal fatty acid content was increased in L-Fabp(-/-)Apc(Min)(/+) mice, and lipidomic profiling of intestinal mucosa revealed significant shifts to polyunsaturated fatty acid species with reduced saturated fatty acid species. L-Fabp(-/-)Apc(Min)(/+) mice also showed corresponding changes in mRNA expression of enzymes involved in fatty acid elongation and desaturation. Furthermore, adenomas from L-Fabp(-/-)Apc(Min)(/+) mice displayed significant reductions in mRNA abundance of nuclear hormone receptors involved in cellular proliferation and in enzymes involved in lipogenesis. These findings collectively implicate L-Fabp as an important genetic modifier of intestinal tumorigenesis, and identify fatty acid trafficking and metabolic compartmentalization as an important pathway linking dietary fat intake, obesity, and intestinal tumor formation.

  13. Sodium Taurocholate Modifies the Bile Acid-Independent Fraction of Canalicular Bile Flow in the Rhesus Monkey

    PubMed Central

    Baker, Alfred L.; Wood, R. A. B.; Moossa, A. R.; Boyer, James L.

    1979-01-01

    Bile acid-independent secretion and the choleretic response to taurocholate were determined in rhesus monkeys fitted with indwelling silastic cannulas in the common bile ducts. Bile acids were infused intravenously in random order at 3.5, 7.0, or 10.5 μmol/min for 1.5 h each. When data were analyzed with a single regression line, bile flow increased in proportion to the level of bile acid secretion, although the y-intercepts (the conventional measurement of bile acid-independent secretion) varied widely (77.9±40.9 ml/24 h). The variation in y-intercepts was observed between animals and with repeated studies in the same animal and could not be explained by sex differences or the effects of the indwelling silastic cannulas, but seemed to be related to the order of bile acid infusion. With only two taurocholic acid infusion rates (7.0 and 3.5 μmol/min), [14C]erythritol clearance was greater per mole of secreted bile acid when the initial bile acid infusion was at the high level, but approached zero at low bile acid secretion rates, which suggests that so-called bile acid-independent canalicular flow is closely related to bile acid secretion or is small in size. The augmentation in [14C]erythritol clearance when the high infusion rate was given first was also associated with an increase in biliary clearance of [3H]inulin, which indicates that the premeability to inulin was also enhanced. Identical experiments which substituted equimolar infusions of a nonmicelle-forming bile acid (taurodehydrocholate) for taurocholate failed to demonstrate any difference in choleretic response or biliary clearance of [3H]inulin with the order of bile acid infusion. These experiments demonstrate that a micelleforming bile acid, taurocholate, can increase the permeability of the biliary system to large molecular weight solutes and simultaneously modify the y-intercept and the volume of bile secreted in response to the transported bile acid. Taurocholate may, therefore, modify its own

  14. In vivo toxicity and immunogenicity of wheat germ agglutinin conjugated poly(ethylene glycol)-poly(lactic acid) nanoparticles for intranasal delivery to the brain

    SciTech Connect

    Liu Qingfeng; Shao Xiayan; Chen Jie; Shen Yehong; Feng Chengcheng; Gao Xiaoling; Zhao Yue; Li Jingwei; Zhang Qizhi Jiang, Xinguo

    2011-02-15

    Biodegradable polymer-based nanoparticles have been widely studied to deliver therapeutic agents to the brain after intranasal administration. However, knowledge as to the side effects of nanoparticle delivery system to the brain is limited. The aim of this study was to investigate the in vivo toxicity and immunogenicity of wheat germ agglutinin (WGA) conjugated poly(ethylene glycol)-poly(lactic acid) nanoparticles (WGA-NP) after intranasal instillation. Sprague-Dawley rats were intranasally given WGA-NP for 7 continuous days. Amino acid neurotransmitters, lactate dehydrogenase (LDH) activity, reduced glutathione (GSH), acetylcholine, acetylcholinesterase activity, tumor necrosis factor {alpha} (TNF-{alpha}) and interleukin-8 (IL-8) in rat olfactory bulb (OB) and brain were measured to estimate the in vivo toxicity of WGA-NP. Balb/C mice were intranasally immunized by WGA-NP and then WGA-specific antibodies in serum and nasal wash were detected by indirect ELISA. WGA-NP showed slight toxicity to brain tissue, as evidenced by increased glutamate level in rat brain and enhanced LDH activity in rat OB. No significant changes in acetylcholine level, acetylcholinesterase activity, GSH level, TNF-{alpha} level and IL-8 level were observed in rat OB and brain for the WGA-NP group. WGA-specific antibodies in mice serum and nasal wash were not increased after two intranasal immunizations of WGA-NP. These results demonstrate that WGA-NP is a safe carrier system for intranasal delivery of therapeutic agents to the brain.

  15. A protease-insensitive feruloyl esterase from China Holstein cow rumen metagenomic library: expression, characterization, and utilization in ferulic acid release from wheat straw.

    PubMed

    Cheng, Fansheng; Sheng, Jiping; Cai, Ting; Jin, Jian; Liu, Wanzhen; Lin, Yanmei; Du, Yongxin; Zhang, Maoqiu; Shen, Lin

    2012-03-14

    A metagenomic library of China Holstein cow rumen microbes was constructed and screened for novel gene cluster. A novel feruloyl esterase (FAE) gene was identified with a length of 789 bp and encoded a protein displaying 56% identity to known esterase sequences. The gene was functionally expressed in Escherichia coli BL21 (DE3), and the total molecular weight of the recombined protein was 32.4 kDa. The purified enzyme showed a broad specificity against the four methyl esters of hydroxycinnamic acids and high activity (259.5 U/mg) to methyl ferulate at optimum conditions (pH 8.0, 40 °C). High thermal and pH stability were also observed. Moreover, the enzyme showed broad resistance to proteases. FAE-SH1 can enhance the release of ferulic acid from wheat straw with cellulase, β-1,4-endoxylanase, β-1,3-glucanase, and pectase. These features suggest FAE-SH1 as a good candidate to enhance biomass degradation and improve the health effects of food and forage.

  16. Inclusion of sunflower seed and wheat dried distillers' grains with solubles in a red clover silage-based diet enhances steers performance, meat quality and fatty acid profiles.

    PubMed

    Mapiye, C; Aalhus, J L; Turner, T D; Vahmani, P; Baron, V S; McAllister, T A; Block, H C; Uttaro, B; Dugan, M E R

    2014-12-01

    The current study compared beef production, quality and fatty acid (FA) profiles of yearling steers fed a control diet containing 70 : 30 red clover silage (RCS) : barley-based concentrate, a diet containing 11% sunflower seed (SS) substituted for barley, and diets containing SS with 15% or 30% wheat dried distillers' grain with solubles (DDGS). Additions of DDGS were balanced by reductions in RCS and SS to maintain crude fat levels in diets. A total of two pens of eight animals were fed per diet for an average period of 208 days. Relative to the control diet, feeding the SS diet increased (P<0.05) average daily gain, final live weight and proportions of total n-6 FA, non-conjugated 18:2 biohydrogenation products (i.e. atypical dienes) with the first double bond at carbon 8 or 9 from the carboxyl end, conjugated linoleic acid isomers with the first double bond from carbon 7 to 10 from the carboxyl end, t-18:1 isomers, and reduced (P<0.05) the proportions of total n-3 FA, conjugated linolenic acids, branched-chain FA, odd-chain FA and 16:0. Feeding DDGS-15 and DDGS-30 diets v. the SS diet further increased (P<0.05) average daily gains, final live weight, carcass weight, hot dressing percentage, fat thickness, rib-eye muscle area, and improved instrumental and sensory panel meat tenderness. However, in general feeding DGGS-15 or DDGS-30 diets did not change FA proportions relative to feeding the SS diet. Overall, adding SS to a RCS-based diet enhanced muscle proportions of 18:2n-6 biohydrogenation products, and further substitutions of DDGS in the diet improved beef production, and quality while maintaining proportions of potentially functional bioactive FA including vaccenic and rumenic acids.

  17. Inclusion of sunflower seed and wheat dried distillers' grains with solubles in a red clover silage-based diet enhances steers performance, meat quality and fatty acid profiles.

    PubMed

    Mapiye, C; Aalhus, J L; Turner, T D; Vahmani, P; Baron, V S; McAllister, T A; Block, H C; Uttaro, B; Dugan, M E R

    2014-12-01

    The current study compared beef production, quality and fatty acid (FA) profiles of yearling steers fed a control diet containing 70 : 30 red clover silage (RCS) : barley-based concentrate, a diet containing 11% sunflower seed (SS) substituted for barley, and diets containing SS with 15% or 30% wheat dried distillers' grain with solubles (DDGS). Additions of DDGS were balanced by reductions in RCS and SS to maintain crude fat levels in diets. A total of two pens of eight animals were fed per diet for an average period of 208 days. Relative to the control diet, feeding the SS diet increased (P<0.05) average daily gain, final live weight and proportions of total n-6 FA, non-conjugated 18:2 biohydrogenation products (i.e. atypical dienes) with the first double bond at carbon 8 or 9 from the carboxyl end, conjugated linoleic acid isomers with the first double bond from carbon 7 to 10 from the carboxyl end, t-18:1 isomers, and reduced (P<0.05) the proportions of total n-3 FA, conjugated linolenic acids, branched-chain FA, odd-chain FA and 16:0. Feeding DDGS-15 and DDGS-30 diets v. the SS diet further increased (P<0.05) average daily gains, final live weight, carcass weight, hot dressing percentage, fat thickness, rib-eye muscle area, and improved instrumental and sensory panel meat tenderness. However, in general feeding DGGS-15 or DDGS-30 diets did not change FA proportions relative to feeding the SS diet. Overall, adding SS to a RCS-based diet enhanced muscle proportions of 18:2n-6 biohydrogenation products, and further substitutions of DDGS in the diet improved beef production, and quality while maintaining proportions of potentially functional bioactive FA including vaccenic and rumenic acids. PMID:25075808

  18. Morphological Analyses of Spring Wheat (CIMMYT cv. PCYT-10) Somaclones

    NASA Technical Reports Server (NTRS)

    Campbell, W. F.; Carman, J. G.; Hashim, Z. N.

    1990-01-01

    The objectives of this study were to induce callus from single immature wheat embryos, produce multiple seedlings from the induced callus, and analyse the somaclonal regenerants for potential grain production in a space garden. Immature wheat, Triticum aestivum L. (cv. PCYT-10), embryos were excised 10 to 12 days post-anthesis and cultured on modified Murashige and Skoog's inorganic salts. Embryos cultured on medium containing kinetin (6-furfurylaminopurine) at 0.5mg/l plus 2 or 3mg/l dicamba (1-methoxy-3,6- dichlorobenzoic acid) or 0.2mg/l 2,4-dichlorophenoxyacetic acid produced calli from which 24, 35 and 39% of the explant tissue exhibited regenerants, respectively. The size of flag leaves, plant heights, tillers per plant, spike lengths, awn lengths, and seeds per spike were significantly different in regenerants of two-selfed recurrent generations (SC(sub 1), SC(sub 2)) than in parental controls. However, there were no significant differences in spikelets per spike between the SC(sub 2) and parental controls. Desirable characteristics that were obtained included longer spikes, more seeds per spike, supernumerary spikelets, and larger flag leaves, variants that should be useful in wheat improvement programs.

  19. Influence of humic acid on the colloidal stability of surface-modified nano zero-valent iron.

    PubMed

    Dong, Haoran; Lo, Irene M C

    2013-01-01

    To enhance colloidal stability of nano zero-valent iron (NZVI) used for groundwater remediation, the surfaces of such NZVI can be modified via coating with organic stabilizers. These surface stabilizers can electrostatically, sterically, or electrosterically stabilize NZVI suspensions in water, but their efficacy is affected by the presence of humic acid (HA) in groundwater. In this study, the effect of HA on the colloidal stability of NZVI coated with three types of stabilizers (i.e., polyacrylic acid (PAA), Tween-20 and starch) was evaluated. Differing stability behaviors were observed for different surface-modified NZVIs (SM-NZVI) in the presence of HA. Fluorescence spectroscopic analysis probed the possible interactions at the SM-NZVI-HA interface, providing a better understanding of the effect of HA on SM-NZVI stability. The adsorption of HA on the surface of PAA-modified NZVI via complexation with NZVI (rather than the PAA stabilizer) enhanced the electrosteric repulsion effect, increasing the stability of the particles. However, for NZVI modified with Tween-20 or starch, HA could interact with the surface stabilizer and apparently play a "bridge" role among the particles, which might induce aggregation of the particles. Therefore, the stability behavior of NZVI modified with Tween-20 or starch might have resulted from the combined effect of "bridging" and "electrosteric" exerted by HA. PMID:23123051

  20. Influence of humic acid on the colloidal stability of surface-modified nano zero-valent iron.

    PubMed

    Dong, Haoran; Lo, Irene M C

    2013-01-01

    To enhance colloidal stability of nano zero-valent iron (NZVI) used for groundwater remediation, the surfaces of such NZVI can be modified via coating with organic stabilizers. These surface stabilizers can electrostatically, sterically, or electrosterically stabilize NZVI suspensions in water, but their efficacy is affected by the presence of humic acid (HA) in groundwater. In this study, the effect of HA on the colloidal stability of NZVI coated with three types of stabilizers (i.e., polyacrylic acid (PAA), Tween-20 and starch) was evaluated. Differing stability behaviors were observed for different surface-modified NZVIs (SM-NZVI) in the presence of HA. Fluorescence spectroscopic analysis probed the possible interactions at the SM-NZVI-HA interface, providing a better understanding of the effect of HA on SM-NZVI stability. The adsorption of HA on the surface of PAA-modified NZVI via complexation with NZVI (rather than the PAA stabilizer) enhanced the electrosteric repulsion effect, increasing the stability of the particles. However, for NZVI modified with Tween-20 or starch, HA could interact with the surface stabilizer and apparently play a "bridge" role among the particles, which might induce aggregation of the particles. Therefore, the stability behavior of NZVI modified with Tween-20 or starch might have resulted from the combined effect of "bridging" and "electrosteric" exerted by HA.

  1. Study of wheat protein based materials

    NASA Astrophysics Data System (ADS)

    Ye, Peng

    Wheat gluten is a naturally occurring protein polymer. It is produced in abundance by the agricultural industry, is biodegradable and very inexpensive (less than $0.50/lb). It has unique viscoelastic properties, which makes it a promising alternative to synthetic plastics. The unplasticized wheat gluten is, however, brittle. Plasticizers such as glycerol are commonly used to give flexibility to the articles made of wheat gluten but with the penalty of greatly reduced stiffness. Former work showed that the brittleness of wheat gluten can also be improved by modifying it with a tri-thiol additive with no penalty of reduced stiffness. However, the cost of the customer designed tri-thiol additive was very high and it was unlikely to make a cost effective material from such an expensive additive. Here we designed a new, inexpensive thiol additive called SHPVA. It was synthesized from polyvinyl alcohol (PVA) through a simple esterification reaction. The mechanical data of the molded wheat gluten/SHPVA material indicated that wheat gluten was toughened by SHPVA. As a control, the wheat gluten/PVA material showed no improvement compared with wheat gluten itself. Several techniques have been used to characterize this novel protein/polymer blend. Differential scanning calorimetric (DSC) study showed two phases in both wheat gluten/PVA and wheat gluten/SHPVA material. However, scanning electron microscope (SEM) pictures indicated that PVA was macroscopically separated from wheat gluten, while wheat gluten/SHPVA had a homogeneous look. The phase image from the atomic force microscope (AFM) gave interesting contrast based on the difference in the mechanical properties of these two phases. The biodegradation behavior of these protein/polymer blends was examined in soil. SHPVA was not degraded in the time period of the experiment. Wheat gluten/SHPVA degraded slower than wheat gluten. We also developed some other interesting material systems based on wheat gluten, including the

  2. Effects of ascorbic acid and high oxygen modified atmosphere packaging during storage of fresh-cut eggplants.

    PubMed

    Li, Xihong; Jiang, Yuqian; Li, Weili; Tang, Yao; Yun, Juan

    2014-03-01

    Ascorbic acid dip and high O2 modified atmosphere packaging were used to alleviate browning and quality loss of fresh-cut eggplants. Fresh-cut eggplants were dipped in water or 0.5% ascorbic acid solution for 2 min before being packed in polyethylene film bags filled with air or high O2. The physiochemical and sensorial attributes of cut eggplants were evaluated during 12 days for storage at 4 . Results demonstrated that high O2 modified atmosphere packaging and ascorbic acid dip improved the preservation of fresh-cut eggplants compared with the control. High O2 showed an ability to reduce the browning and inhibit polyphenol oxidase and peroxidase activities. Higher total phenolic content and lower malondialdehyde content were also observed in ascorbic acid treated samples during storage. Moreover, the combination of ascorbic acid and high O2 was more effective than single treatments. The surface color was protected by ascorbic acid and high O2 packaging, and higher sensory scores were observed after 12 days of storage.

  3. Hydroxyapatite surface modified by L-lactic acid and its subsequent grafting polymerization of L-lactide.

    PubMed

    Qiu, Xueyu; Hong, Zhongkui; Hu, Junli; Chen, Li; Chen, Xuesi; Jing, Xiabin

    2005-01-01

    A new method of surface modification of hydroxyapatite nanoparticles (n-HA) by surface grafting reaction of l-lactic acid and ring-opening polymerization of l-lactide (LLA) was developed. Two modified HA nanoparticles were obtained: HA modified by l-lactic acid (l-HA) and HA grafting with poly(l-lactide) (PLLA; p-HA). The modified surface of n-HA was attested by Fourier transformation infrared, (31)P MAS NMR, and thermal gravimetric analysis. The results showed that l-lactic acid could be easily grafted onto the n-HA surface by forming a Ca carboxylate bond and initiated by the hydroxyl group of the grafted l-lactic acid and LLA could be graft-polymerized onto the n-HA surface in the presence of stannous octanoate. The highest grafting amounts of l-lactic acid and PLLA were about 33 and 22 wt %, respectively. The modified HA/PLLA composites showed good mechanical properties and uniform microstructure. The tensile strength and modulus of the p-HA/PLLA composite containing 15 wt % of p-HA were 67 MPa and 2.1 GPa, respectively, while those of the n-HA/PLLA composites were 45 MPa and 1.7 GPa, respectively. The elongation at the break of the l-HA/PLLA composite containing 15 wt % l-HA could reach 44%, in comparison with 6.5% of the n-HA/PLLA composites containing 15 wt % n-HA. PMID:15877333

  4. Effect of grain colour gene (R) on grain dormancy and sensitivity of the embryo to abscisic acid (ABA) in wheat.

    PubMed

    Himi, Eiko; Mares, Daryl J; Yanagisawa, Akira; Noda, Kazuhiko

    2002-07-01

    The level of grain dormancy and sensitivity to ABA of the embryo, a key factor in grain dormancy, were examined in developing grains of a white-grained wheat line, Novosibirskaya 67 (NS-67), and its red-grained near-isogenic lines (ANK-1A to -1D); a red-grained line, AUS 1490, and its white-grained mutant line (EMS-AUS). ANK lines showed higher levels of grain dormancy than NS-67 at harvest maturity. AUS 1490 grain also showed higher dormancy than EMS-AUS grain. These results suggest that the R gene for grain colour can enhance grain dormancy. However, the dormancy effect conferred by the R gene was not large, suggesting that it plays a minor role in the development of grain dormancy. Water extracts of AUS 1490 and EMS-AUS bran contained germination inhibitors equivalent to 1-10 microM ABA, although there was no difference in the amount of inhibitors between AUS 1490 and EMS-AUS. Thus, the grain colour gene of AUS 1490 did not appear to enhance the level of grain dormancy by accumulating germination inhibitors in its bran. Sensitivity to ABA of embryos was higher in grains collected around harvest-maturity for ANK lines and AUS 1490, compared with NS-67 and EMS-AUS. The R gene might enhance grain dormancy by increasing the sensitivity of embryos to ABA.

  5. Interactive intoxicating and ameliorating effects of tannic acid, aluminum (Al), copper (Cu), and selenate (SeO) in wheat roots: a descriptive and mathematical assessment.

    PubMed

    Kinraide, Thomas B; Hagermann, Ann E

    2010-05-01

    Tannic acids and tannins are produced by plants and are important components of soil and water organic matter. These polyphenolic compounds form complexes with proteins, metals and soil particulate matter and perform several physiological and ecological functions. The tannic acid (TA) used in our study was a mixture of gallic acid and galloyl glucoses ranging up to nonagalloyl glucose. TA inhibited root elongation in wheat seedlings (Triticum aestivum L. cv. Scout 66) at concentrations >4 mg l(-1); but TA alleviated the toxicity of Al(3+), Cu(2+) and SeO(4)(2-); and Al(3+) and SeO(4)(2-) alleviated the toxicity of TA. The interactions of Al(3+) and TA (each toxic but each alleviating the toxicity of the other) were stoichiometric. Growth was affected as though 1 kg TA bound 2.76 mol Al so strongly that if (mol Al)/(kg TA) <2.76, then free Al approximately 0, and if (mol Al)/(kg TA) >2.76, then free TA approximately 0. This stoichiometry is consistent with one mole of galloyl groups binding approximately 0.5 mol Al. Using this binding scheme, growth was modeled successfully on the basis of free TA and free Al. TA enhanced the negativity of root surfaces and enhanced the binding of Al and Cu there without enhancing their toxicity. These and other interactions among TA, Al(3+), Cu(2+), SeO(4)(2-), Ca(2+), Na(+) and H(+) were quantified with a comprehensive non-linear equation with statistically significant coefficients.

  6. Determination of Acid Herbicides Using Modified QuEChERS with Fast Switching ESI(+)/ESI(-) LC-MS/MS.

    PubMed

    Sack, Chris; Vonderbrink, John; Smoker, Michael; Smith, Robert E

    2015-11-01

    A method for the determination of 35 acid herbicides in food matrices was developed, validated, and implemented. It utilizes a modified QuEChERS extraction procedure coupled with quantitation by liquid chromatography tandem mass spectrometry (LC-MS/MS). The acid herbicides analyzed are all organic carboxylic acids, including the older chlorophenoxy acid herbicides such as 2,4-dichlorophenoxyacetic acid (2,4-D), dicamba, 4-chlorophenoxyacetic acid (4-CPA), quinclorac, and many of the newer imidazolinone herbicides such as imazethapyr and imazaquin. In the procedure, 10 mL of water is added to 5 g of sample and then extracted with 1% formic acid in acetonitrile for 1 min. The acetonitrile phase is salted out of the extract by adding sodium chloride and magnesium sulfate, followed by centrifugation. The acetonitrile is diluted 1:1 with water to enable quantitation by LC-MS/MS using fast switching between positive and negative electrospray ionization modes. The average recoveries for all the compounds except aminocyclopyrachlor were 95% with a precision of 8%. The method detection limits for all residues were less than 10 ng/g, and the correlation coefficients for the calibration curves was greater than 0.99 for all but two compounds tested. The method was used successfully for the quantitation of acid herbicides in the FDA's total diet study. The procedure proved to be accurate, precise, linear, sensitive, and rugged.

  7. The erosion kinetics of conventional and resin-modified glass-ionomer luting cements in acidic buffer solutions.

    PubMed

    Hazar-Yoruc, Binnaz; Bavbek, Andac Barkin; Özcan, Mutlu

    2012-01-01

    This study investigated the erosion kinetics of conventional and resin-modified glass-ionomer luting cements in acidic buffer solutions as a function of time. Disc shaped specimens were prepared from conventional (Ketac-Cem: KTC) and resin-modified glass ionomer cements (Fuji Plus: FP) and immersed in three acidic buffer solutions (0.01 M) namely, acetic acid/sodium acetate (AA(B)), lactic acid/sodium lactate (LA(B)) and citric acid/sodium citrate (CA(B)) with a constant pH of 4.1 and stored for 1, 8, 24, 48, 80, 120 and 168 h. F concentration was determined using ion-specific electrode. Si, Ca and Al concentrations were determined by atomic absorption spectroscopy. Ca, Al, Si and F solubility rates in both FP and KTC were the highest in CA(B) solution. The erosion rates of both FP and KTC in all buffer solutions increased as a function of immersion time. The amount of F eluted from FP was more than that of KTC. The total amount of elements released from FP was less than KTC in all solutions. PMID:23207217

  8. Voltammetric determination of polyphenolic content in pomegranate juice using a poly(gallic acid)/multiwalled carbon nanotube modified electrode

    PubMed Central

    Newair, Emad F

    2016-01-01

    Summary A simple and sensitive poly(gallic acid)/multiwalled carbon nanotube modified glassy carbon electrode (PGA/MWCNT/GCE) electrochemical sensor was prepared for direct determination of the total phenolic content (TPC) as gallic acid equivalent. The GCE working electrode was electrochemically modified and characterized using scanning electron microscope (SEM), cyclic voltammetry (CV), chronoamperometry and chronocoulometry. It was found that gallic acid (GA) exhibits a superior electrochemical response on the PGA/MWCNT/GCE sensor in comparison with bare GCE. The results reveal that a PGA/MWCNT/GCE sensor can remarkably enhance the electro-oxidation signal of GA as well as shift the peak potentials towards less positive potential values. The dependence of peak current on accumulation potential, accumulation time and pH were investigated by square-wave voltammetry (SWV) to optimize the experimental conditions for the determination of GA. Using the optimized conditions, the sensor responded linearly to a GA concentration throughout the range of 4.97 × 10−6 to 3.38 × 10−5 M with a detection limit of 3.22 × 10−6 M (S/N = 3). The fabricated sensor shows good selectivity, stability, repeatability and (101%) recovery. The sensor was successfully utilized for the determination of total phenolic content in fresh pomegranate juice without interference of ascorbic acid, fructose, potassium nitrate and barbituric acid. The obtained data were compared with the standard Folin–Ciocalteu spectrophotometric results. PMID:27547628

  9. Voltammetric determination of polyphenolic content in pomegranate juice using a poly(gallic acid)/multiwalled carbon nanotube modified electrode.

    PubMed

    Abdel-Hamid, Refat; Newair, Emad F

    2016-01-01

    A simple and sensitive poly(gallic acid)/multiwalled carbon nanotube modified glassy carbon electrode (PGA/MWCNT/GCE) electrochemical sensor was prepared for direct determination of the total phenolic content (TPC) as gallic acid equivalent. The GCE working electrode was electrochemically modified and characterized using scanning electron microscope (SEM), cyclic voltammetry (CV), chronoamperometry and chronocoulometry. It was found that gallic acid (GA) exhibits a superior electrochemical response on the PGA/MWCNT/GCE sensor in comparison with bare GCE. The results reveal that a PGA/MWCNT/GCE sensor can remarkably enhance the electro-oxidation signal of GA as well as shift the peak potentials towards less positive potential values. The dependence of peak current on accumulation potential, accumulation time and pH were investigated by square-wave voltammetry (SWV) to optimize the experimental conditions for the determination of GA. Using the optimized conditions, the sensor responded linearly to a GA concentration throughout the range of 4.97 × 10(-6) to 3.38 × 10(-5) M with a detection limit of 3.22 × 10(-6) M (S/N = 3). The fabricated sensor shows good selectivity, stability, repeatability and (101%) recovery. The sensor was successfully utilized for the determination of total phenolic content in fresh pomegranate juice without interference of ascorbic acid, fructose, potassium nitrate and barbituric acid. The obtained data were compared with the standard Folin-Ciocalteu spectrophotometric results.

  10. Simultaneous determination of ofloxacin and gatifloxacin on cysteic acid modified electrode in the presence of sodium dodecyl benzene sulfonate.

    PubMed

    Zhang, Fenfen; Gu, Shuqing; Ding, Yaping; Li, Li; Liu, Xiao

    2013-02-01

    A novel cysteic acid modified carbon paste electrode (cysteic acid/CPE) based on electrochemical oxidation of L-cysteine was developed to simultaneously determine ofloxacin and gatifloxacin in the presence of sodium dodecyl benzene sulfonate (SDBS). Fourier transform infrared spectra (FTIR) indicated that L-cysteine was oxidated to cysteic acid. Electrochemical impedance spectroscopy (EIS) and cyclic voltammograms (CV) indicated that cysteic acid was successfully modified on electrode. The large peak separation (116 mV) between ofloxacin and gatifloxacin was obtained on cysteic acid/CPE while only one oxidation peak was found on bare electrode. And the peak currents increased 5 times compared to bare electrode. Moreover, the current could be further enhanced in the presence of an anionic surfactant, sodium dodecyl benzene sulfonate. The differential pulse voltammograms (DPV) exhibited that the oxidation peak currents were linearly proportional to their concentrations in the range of 0.06-10 μM for ofloxacin and 0.02-200 μM for gatifloxacin, and the detection limits of ofloxacin and gatifloxacin were 0.02 μM and 0.01 μM (S/N=3), respectively. This proposed method was successfully applied to determine ofloxacin and gatifloxacin in pharmaceutical formulations and human serum samples.

  11. Voltammetric determination of polyphenolic content in pomegranate juice using a poly(gallic acid)/multiwalled carbon nanotube modified electrode.

    PubMed

    Abdel-Hamid, Refat; Newair, Emad F

    2016-01-01

    A simple and sensitive poly(gallic acid)/multiwalled carbon nanotube modified glassy carbon electrode (PGA/MWCNT/GCE) electrochemical sensor was prepared for direct determination of the total phenolic content (TPC) as gallic acid equivalent. The GCE working electrode was electrochemically modified and characterized using scanning electron microscope (SEM), cyclic voltammetry (CV), chronoamperometry and chronocoulometry. It was found that gallic acid (GA) exhibits a superior electrochemical response on the PGA/MWCNT/GCE sensor in comparison with bare GCE. The results reveal that a PGA/MWCNT/GCE sensor can remarkably enhance the electro-oxidation signal of GA as well as shift the peak potentials towards less positive potential values. The dependence of peak current on accumulation potential, accumulation time and pH were investigated by square-wave voltammetry (SWV) to optimize the experimental conditions for the determination of GA. Using the optimized conditions, the sensor responded linearly to a GA concentration throughout the range of 4.97 × 10(-6) to 3.38 × 10(-5) M with a detection limit of 3.22 × 10(-6) M (S/N = 3). The fabricated sensor shows good selectivity, stability, repeatability and (101%) recovery. The sensor was successfully utilized for the determination of total phenolic content in fresh pomegranate juice without interference of ascorbic acid, fructose, potassium nitrate and barbituric acid. The obtained data were compared with the standard Folin-Ciocalteu spectrophotometric results. PMID:27547628

  12. Zinc oxide modified with benzylphosphonic acids as transparent electrodes in regular and inverted organic solar cell structures

    SciTech Connect

    Lange, Ilja; Reiter, Sina; Kniepert, Juliane; Piersimoni, Fortunato; Brenner, Thomas; Neher, Dieter; Pätzel, Michael; Hildebrandt, Jana; Hecht, Stefan

    2015-03-16

    An approach is presented to modify the work function of solution-processed sol-gel derived zinc oxide (ZnO) over an exceptionally wide range of more than 2.3 eV. This approach relies on the formation of dense and homogeneous self-assembled monolayers based on phosphonic acids with different dipole moments. This allows us to apply ZnO as charge selective bottom electrodes in either regular or inverted solar cell structures, using poly(3-hexylthiophene):phenyl-C71-butyric acid methyl ester as the active layer. These devices compete with or even surpass the performance of the reference on indium tin oxide/poly(3,4-ethylenedioxythiophene) polystyrene sulfonate. Our findings highlight the potential of properly modified ZnO as electron or hole extracting electrodes in hybrid optoelectronic devices.

  13. Modifications of wheat germ cell-free system for functional proteomics of plant membrane proteins.

    PubMed

    Nozawa, Akira; Tozawa, Yuzuru

    2014-01-01

    Functional proteomics of plant membrane proteins is an important approach to understand the comprehensive architecture of each metabolic pathway in plants. One bottleneck in the characterization of membrane proteins is the difficulty in producing sufficient quantities of functional protein for analysis. Here, we describe three methods for membrane protein production utilizing a wheat germ cell-free protein expression system. Owing to the open nature of cell-free synthesis reaction, protein synthesis can be modified with components necessary to produce functional protein. In this way we have developed modifications to a wheat germ cell-free system for the production of functional membrane proteins. Supplementation of liposomes or detergents allows the synthesis of functional integral membrane proteins. Furthermore, supplementation of myristic acid enables synthesis of N-myristylated peripheral membrane proteins. These modified cell-free synthesis methods facilitate the preparation and subsequent functional analyses of a wide variety of membrane proteins. PMID:24136528

  14. Modified branched-chain amino acid pathways give rise to acyl acids of sucrose esters exuded from tobacco leaf trichomes.

    PubMed

    Kandra, G; Severson, R; Wagner, G J

    1990-03-10

    A major diversion of carbon from branched-chain amino acid biosynthesis/catabolism to form acyl moieties of sucrose esters (6-O-acetyl-2,3,4-tri-O-acyl-alpha-D-glucopyranosyl-beta-D- fructofuranosides) was observed to be associated with specialized trichome head cells which secrete large amounts of sucrose esters. Surface chemistry and acetyl and acyl substituent groups of tobacco (T.I. 1068) sucrose esters were identified and quantified by gas chromatography/mass spectrometry. Sucrose esters were prominent surface constituents and 3-methylvaleric acid, 2- and 3-methylbutyric acid, and methylpropionic acid accounted for 60%, 25% and 9%, respectively, of total C3--C7 acyl substituents. Radiolabeled Thr, Ile, Val, Leu, pyruvate and Asp, metabolites of branched-chain amino acid pathways, were compared with radioactively labeled acetate and sucrose as donors of carbon to sucrose, acetyl and acyl components of sucrose esters using epidermal peels with undisturbed trichomes. Preparations of biosynthetically competent trichome heads (site of sucrose ester formation) were also examined. Results indicate that 3-methylvaleryl and 2-methylbutyryl groups are derived from the Thr pathway of branched-chain amino acid metabolism, 3-methylbutyryl and methylpropionyl groups are formed via the pyruvate pathway, and that acetyl groups are principally formed directly via acetyl-CoA. Arguments are presented which rule out participation of fatty acid synthase in the formation of prominent acyl acids. Results suggest that the shunting of carbon away from the biosynthesis of Val, Leu and Ile may be due to a low level of amino acid utilization in protein synthesis in specialized glandular head cells of trichomes. This would result in the availability of corresponding oxo acids for CoA activation and esterification to form sucrose esters. Preliminary evidence was found for the involvement of cycling reactions in oxo-acid-chain lengthening and for utilization of pyruvate-derived 2

  15. Fabrication of chiral amino acid ionic liquid modified magnetic multifunctional nanospheres for centrifugal chiral chromatography separation of racemates.

    PubMed

    Liu, Yating; Tian, Ailin; Wang, Xiong; Qi, Jing; Wang, Fengkang; Ma, Ying; Ito, Yoichiro; Wei, Yun

    2015-06-26

    As the rapid development of nanotechnology, the magnetic nanospheres modified with special chiral selective ligands show a great potentiality in enantiomeric separation. In this study, magnetic nanospheres modified with task-specific chiral ionic liquid were designed for the separation of chiral amino acids. These modified magnetic nanospheres were effective in a direct chiral separation of five racemic amino acids (D- and L-cysteine, D- and L-arginine, D- and L-leucine, D- and L-glutamine and D- and L-tryptophan). Furthermore, a new online method for complete separation of the enantiomers via the magnetic nanospheres was established with centrifugal chiral chromatography using a spiral tube assembly mounted on a type-J coil planet centrifuge. One kind of chiral compounds, D- and L-tryptophan was resolved well using this method. These results demonstrated that the modified nanospheres display a good chiral recognition ability, and can be used as a potential material for chiral separation of various racemates.

  16. Modified biopolymers as sorbents for the removal of naphthenic acids from oil sands process affected water (OSPW).

    PubMed

    Arshad, Muhammad; Khosa, M A; Siddique, Tariq; Ullah, Aman

    2016-11-01

    Oil sands operations consume large volumes of water in bitumen extraction process and produce tailings that express pore water to the surface of tailings ponds known as oil sands process-affected water (OSPW). The OSPW is toxic and cannot be released into the environment without treatment. In addition to metals, dissolved solids, dissolved gases, hydrocarbons and polyaromatic compounds etc., OSPW also contains a complex mixture of dissolved organic acids, referred to as naphthenic acids (NAs). The NAs are highly toxic and react with metals to develop highly corrosive functionalities which cause corrosion in the oil sands processing and refining processes. We have chemically modified keratin biopolymer using polyhedral oligomeric silsesquioxanes (POSS) nanocages and goethite dopant to unfold keratinous structure for improving functionality. The untreated neat keratin and two modified sorbents were characterized to investigate structural, morphological, dimensional and thermal properties. These sorbents were then tested for the removal of NAs from OSPW. The NAs were selectively extracted and quantified before and after sorption process. The biosorption capacity (Q), rejection percentage (R%) and isotherm models were studied to investigate NAs removal efficiency of POSS modified keratin biopolymer (PMKB) and goethite modified keratin biopolymer (GMKB) from aliquots of OSPW. PMID:27552693

  17. Modified biopolymers as sorbents for the removal of naphthenic acids from oil sands process affected water (OSPW).

    PubMed

    Arshad, Muhammad; Khosa, M A; Siddique, Tariq; Ullah, Aman

    2016-11-01

    Oil sands operations consume large volumes of water in bitumen extraction process and produce tailings that express pore water to the surface of tailings ponds known as oil sands process-affected water (OSPW). The OSPW is toxic and cannot be released into the environment without treatment. In addition to metals, dissolved solids, dissolved gases, hydrocarbons and polyaromatic compounds etc., OSPW also contains a complex mixture of dissolved organic acids, referred to as naphthenic acids (NAs). The NAs are highly toxic and react with metals to develop highly corrosive functionalities which cause corrosion in the oil sands processing and refining processes. We have chemically modified keratin biopolymer using polyhedral oligomeric silsesquioxanes (POSS) nanocages and goethite dopant to unfold keratinous structure for improving functionality. The untreated neat keratin and two modified sorbents were characterized to investigate structural, morphological, dimensional and thermal properties. These sorbents were then tested for the removal of NAs from OSPW. The NAs were selectively extracted and quantified before and after sorption process. The biosorption capacity (Q), rejection percentage (R%) and isotherm models were studied to investigate NAs removal efficiency of POSS modified keratin biopolymer (PMKB) and goethite modified keratin biopolymer (GMKB) from aliquots of OSPW.

  18. Detection of SEB gene by bilayer lipid membranes nucleic acid biosensor supported by modified patch-clamp pipette electrode.

    PubMed

    Liu, Nan; Gao, Zhixian; Zhou, HuanYing; Yue, Mingxiang

    2007-04-15

    This work reports a kind of novel bilayer lipid membranes (BLMs) nucleic acid biosensor supported by modified patch-clamp pipette electrode was developed to detect staphylococcus enterotoxins B (SEB) gene. BLMs were formed within 15 min and able to be operated at least 24 h. Hydrophobic dodecane tail (C12) modified 18 bp single-stranded DNA (ssDNA) probe was immobilized on BLMs. The electrochemical currents versus the different concentration of ssDNA probe immobilized on BLMs indicated linearly correlation. The BLMs nucleic acid biosensor was fabricated by selecting the ssDNA probe as the signal sensing element with the concentration of 273.65 ng/mL. The electrochemical performance of the biosensor for the detection of SEB was investigated. The result showed that linear relationship was found between the current and ln(concentration) from 20 to 5000 ng/mL and the detection limit was 20 ng/mL. In addition, the biosensor was specific response to SEB gene and showed no significant current alteration in electrolyte which containing no SEB gene. Finally, Atom Force Microscope (AFM) images could be observed and used to evaluate the superficial microstructure of BLMs, ssDNA immobilized on BLMs and BLMs after hybridization. The BLMs nucleic acid biosensor supported by modified patch-clamp pipette electrode will become a highly sensitive, rapid, selective analytical tool for detection of Staphylococcus aureus, which produce SEB. PMID:17092700

  19. Preparation and characterization of acorn starch/poly(lactic acid) composites modified with functionalized vegetable oil derivates.

    PubMed

    Li, Shouhai; Xia, Jianling; Xu, Yuzhi; Yang, Xuejuan; Mao, Wei; Huang, Kun

    2016-05-20

    Composites of acorn starch (AS) and poly(1actic acid) (PLA) modified with dimer fatty acid (DFA) or dimer fatty acid polyamide (DFAPA) were produced by a hot-melt extrusion method. The effects of DFA and DFAPA contents on the mechanical, hydrophobic, thermal properties and melt fluidity of the composites were studied under an invariable AS-to-PLA mass ratio of 40/60. SEM and DMA research results show that the compatibility of AS/PLA composites are determined by the dosage of DFA or DFAPA. The hydrophobicity and melt fluidity of composites are improved with the addition of DFA and DFAPA. The glass transition temperatures of the composites are all reduced remarkably by additives DFA and DFAPA. However, DFA and DFAPA exert different effects on the mechanical properties of AS/PLA composites. In the DFAPA-modified system, the tensile and flexural strength first increase and then decrease with the increase of DFAPA dosage; the mechanical strength is maximized when the dosage of DFAPA is 2 wt% of total weight. In the DFA-modified system, the tensile and flexural strength decrease with the increase of DFA dosage.

  20. Quantitation of Aristolochic Acids in Corn, Wheat Grain, and Soil Samples Collected in Serbia: Identifying a Novel Exposure Pathway in the Etiology of Balkan Endemic Nephropathy.

    PubMed

    Chan, Wan; Pavlović, Nikola M; Li, Weiwei; Chan, Chi-Kong; Liu, Jingjing; Deng, Kailin; Wang, Yinan; Milosavljević, Biljana; Kostić, Emina N

    2016-07-27

    While to date investigations provided convincing evidence on the role of aristolochic acids (AAs) in the etiology of Balkan endemic nephropathy (BEN) and upper urothelial cancer (UUC), the exposure pathways by which AAs enter human bodies to cause BEN and UUC remain obscure. The goal of this study is to test the hypothesis that environmental pollution by AAs and root uptake of AAs in the polluted soil may be one of the pathways by which AAs enter the human food chain. The hypothesis driving this study was that the decay of Aristolochia clematitis L., a AA-containing herbaceous plant that is found growing widespread in the endemic regions, could release free AAs to the soil, which could be taken up by food crops growing nearby, thereby transferring this potent human nephrotoxin and carcinogen into their edible parts. Using the highly sensitive and selective high-performance liquid chromatography coupled with fluorescence detection method, we identified and quantitated in this study for the first time AAs in corn, wheat grain, and soil samples collected from the endemic village Kutles in Serbia. Our results provide the first direct evidence that food crops and soil in the Balkans are contaminated with AAs. It is possible that the presence of AAs in edible parts of crops originating from the AA-contaminated soil could be one of the major pathways by which humans become exposed to AAs. PMID:27362729

  1. Changes in the water status and osmotic solute contents in response to drought and salicylic acid treatments in four different cultivars of wheat (Triticum aestivum).

    PubMed

    Loutfy, Naglaa; El-Tayeb, Mohamed A; Hassanen, Ahmed M; Moustafa, Mahmoud F M; Sakuma, Yoh; Inouhe, Masahiro

    2012-01-01

    Salicylic acid (SA) controls growth and stress responses in plants. It also induces drought tolerance in plants. In this paper, four wheat (Triticum aestivum L.) cultivars with different drought responses were treated with SA in three levels of drain (90, 60, 30% of maximum field capacity) to examine its interactive effects on drought responses and contents of osmotic solutes that may be involved in growth and osmotic adjustment. Under drought condition, the cultivars Geza 164 and Sakha 69 had the plant biomass and leaf relative water content (LRWC) greater than the cultivars Gemaza 1 and Gemaza 3. In all cultivars, drought stress decreased the biomass, LRWC, and the contents of inorganic solutes (Ca, K, Mg) and largely increased the contents of organic solutes (soluble sugars and proline). By contrast, SA increased the biomass, LRWC and the inorganic and organic solute contents, except proline. Correlation analysis revealed that the LRWC correlated positively with the inorganic solute contents but negatively with proline in all cultivars. SA caused maximum accumulations of soluble sugars in roots under drought. These results indicated that SA-enhanced tolerance might involve solute accumulations but independently of proline biosynthesis. Drought-sensitive cultivars had a trait lowering Ca and K levels especially in shoots. Possible functions of the ions and different traits of cultivars were discussed.

  2. Effect of additives on adsorption and desorption behavior of xylanase on acid-insoluble lignin from corn stover and wheat straw.

    PubMed

    Li, Yanfei; Ge, Xiaoyan; Sun, Zongping; Zhang, Junhua

    2015-06-01

    The competitive adsorption between cellulases and additives on lignin in the hydrolysis of lignocelluloses has been confirmed, whereas the effect of additives on the interaction between xylanase and lignin is not clear. In this work, the effects of additives, poly(ethylene glycol) 2000, poly(ethylene glycol) 6000, Tween 20, and Tween 80, on the xylanase adsorption/desorption onto/from acid-insoluble lignin from corn stover (CS-lignin) and wheat straw (WS-lignin) were investigated. The results indicated that the additives could adsorb onto isolated lignin and reduce the xylanase adsorption onto lignin. Compared to CS-lignin, more additives could adsorb onto WS-lignin, making less xylanase adsorbed onto WS-lignin. In addition, the additives could enhance desorption of xylanase from lignin, which might be due to the competitive adsorption between xylanase and additives on lignin. The released xylanase from lignin still exhibited hydrolytic capacity in the hydrolysis of isolated xylan and xylan in corn stover.

  3. Surfactant-modified fatty acid composition of Citrobacter sp. SA01 and its effect on phenanthrene transmembrane transport.

    PubMed

    Li, Feng; Zhu, Lizhong

    2014-07-01

    The effects of the surfactants, Tween 80 and sodium dodecyl benzene sulfonate (SDBS) on a membrane's fatty acid composition and the transmembrane transport of phenanthrene were investigated. The results indicated that both surfactants could modify the composition of fatty acids of Citrobacter sp. Strain SA01 cells, 50 mg L(-1) of both surfactants changed the composition of the fatty acids the most, increasing the amount of unsaturated fatty acids. The comparison of fatty acid profiles with diphenylhexatriene fluorescence anisotropy, a probe for plasma membrane fluidity, suggested that an increased amount of unsaturated fatty acids corresponded to greater membrane fluidity. In addition, increased unsaturated fatty acids promoted phenanthrene to partition from the extracellular matrix to cell debris, which increased reverse partitioning from the cell debris to the cytochylema. The results of this study were expected in that the addition of a surfactant is a simple and effective method for accelerating the rate-limiting step of transmembrane transport of hydrophobic organic compounds (HOCs) in bioremediation.

  4. Wear-resistant and electromagnetic absorbing behaviors of oleic acid post-modified ferrite-filled epoxy resin composite coating

    NASA Astrophysics Data System (ADS)

    Wang, Wenjie; Zang, Chongguang; Jiao, Qingjie

    2015-03-01

    The post-modified Mn-Zn ferrite was prepared by grafting oleic acid on the surface of Mn-Zn ferrite to inhibit magnetic nanoparticle aggregation. Fourier Transform Infrared (FT-IR) spectroscopy was used to characterize the particle surfaces. The friction and electromagnetic absorbing properties of a thin coating fabricated by dispersing ferrite into epoxy resin (EP) were investigated. The roughness of the coating and water contact angle were measured using the VEECO and water contact angle meter. Friction tests were conducted using a stainless-steel bearing ball and a Rockwell diamond tip, respectively. The complex permittivity and complex permeability of the composite coating were studied in the low frequency (10 MHz-1.5 GHz). Surface modified ferrites are found to improve magnetic particles dispersion in EP resulting in significant compatibility between inorganic and organic materials. Results also indicate that modified ferrite/EP coatings have a lower roughness average value and higher water contact angle than original ferrite/EP coatings. The enhanced tribological properties of the modified ferrite/EP coatings can be seen from the increased coefficient value. The composite coatings with modified ferrite are observed to exhibit better reflection loss compared with the coatings with original ferrite.

  5. Fermented and extruded wheat bran in piglet diets: impact on performance, intestinal morphology, microbial metabolites in chyme and blood lipid radicals.

    PubMed

    Kraler, Manuel; Schedle, Karl; Schwarz, Christiane; Domig, Konrad J; Pichler, Martin; Oppeneder, Alexander; Wetscherek, Wolfgang; Prückler, Michael; Pignitter, Marc; Pirker, Katharina F; Somoza, Veronika; Heine, Daniel; Kneifel, Wolfgang

    2015-01-01

    The aim of the present study was to evaluate the influence of native, fermented and extruded wheat bran on the performance and intestinal morphology of piglets. Additionally, short-chain fatty acids (SCFA), biogenic amines, ammonia, lactic acid, pH as well as E. coli and lactic acid bacterial counts were analysed in digesta samples from three gut sections. Furthermore, the antioxidant potential in blood samples was evaluated based on the lipid radicals formed. For this purpose, 48 newly weaned piglets (28 d old) were allocated to one of the four different dietary treatment groups: no wheat bran (Control), native wheat bran, fermented wheat bran as well as extruded wheat bran. Wheat bran variants were included at 150 g/kg into the diets. All diets were mixed to reach the calculated isonitrogenic nutrient contents. Gut tissue and digesta samples were collected from the proximal jejunum, the terminal ileum and the colon ascendens, blood samples directly at slaughter. Although none of the dietary interventions had an impact on performance parameters, the amount of goblet cells in the ileum was increased upon feeding native and extruded wheat bran, compared to fermented bran (p < 0.05). The E. coli counts in colonic chyme were significantly lower (p < 0.05) in the Control group compared to the groups fed with wheat bran. The concentration of SCFA showed differences for minor compounds (p < 0.05), while linear contrast analyses revealed a reduced concentration of total SCFA in the colon following the feeding of modified wheat bran compared to native wheat bran. This may suggest that several compounds are more easily digested already in the ileum, resulting in a reduced nutrient flow into the large intestine and therefore less unexploited digesta is available as substrate for the microorganisms there. Fermentation also resulted in a significant decrease of methylamine in the colon (p < 0.05), while other biogenic amines in the ileum and colon showed no

  6. A Nucleic Acid Biosensor for Detection of Hepatitis C Virus Genotype 1a Using Poly(L-Glutamic Acid)-Modified Electrode.

    PubMed

    Donmez, Soner; Arslan, Fatma; Arslan, Halit

    2015-07-01

    An electrochemical nucleic acid biosensor based on label-free DNA detection method was prepared for the first time by using electropolymerized poly(L-glutamic acid)-modified pencil graphite electrode (PGA/PGE) for detection of hepatitis C virus genotype 1a (HCV1a). Inosine-substituted 20-mer probes related to the HCV1a were immobilized onto PGA/PGE surface by covalent linking with the formation of amide bonds. Square wave voltammetry (SWV) was used to monitor the oxidation signal of guanine in the hybridization events, which gave an oxidation peak at +1.05 V. An increase in the oxidation signal of guanine was showed by hybridization of the probe with the complementary DNA. Noncomplementary oligonucleotides were also used to investigate the selectivity of the biosensor. The proposed nucleic acid biosensor was linear in the range of 50 nM to 1.0 μM, exhibiting a limit of detection of 40.6 nM. Finally, single-stranded synthetic PCR product analogues of HCV1a were performed in optimal condition. This PGA-modified nucleic acid sensor is cost-effective and disposable, and besides, it has superior electrocatalytic effect on the oxidation of guanine. PMID:25947619

  7. Mapping of Saccharomyces cerevisiae metabolites in fermenting wheat straight-dough reveals succinic acid as pH-determining factor.

    PubMed

    Jayaram, Vinay B; Cuyvers, Sven; Lagrain, Bert; Verstrepen, Kevin J; Delcour, Jan A; Courtin, Christophe M

    2013-01-15

    Fermenting yeast does not merely cause dough leavening, but also contributes to the bread aroma and might alter dough rheology. Here, the yeast carbon metabolism was mapped during bread straight-dough fermentation. The concentration of most metabolites changed quasi linearly as a function of fermentation time. Ethanol and carbon dioxide concentrations reached up to 60 mmol/100g flour. Interestingly, high levels of glycerol (up to 10 mmol/100g flour) and succinic acid (up to 1.6 mmol/100g flour) were produced during dough fermentation. Further tests showed that, contrary to current belief, the pH decrease in fermenting dough is primarily caused by the production of succinic acid by the yeast instead of carbon dioxide dissolution or bacterial organic acids. Together, our results provide a comprehensive overview of metabolite production during dough fermentation and yield insight into the importance of some of these metabolites for dough properties.

  8. Dispersion in the presence of acetic acid or ammonia confers gliadin-like characteristics to the glutenin in wheat gluten.

    PubMed

    Murakami, Tetsuya; Kitabatake, Naofumi; Tani, Fumito

    2015-02-01

    Spray-dried gluten has unique properties and is commercially available in the food industry worldwide. In this study, we examined the viscoelastic properties of gluten powder prepared by dispersion in the presence of acetic acid or an ammonia solvent and then followed by lyophilization instead of a spray drying. Mixograph measurements showed that the acid- and ammonia-treated gluten powders had marked decreases in the time to peak dough resistance when compared with the control gluten powder. The integrals of the dough resistance and bandwidth for 3 min after peak dough resistance decreased in both treated gluten powders. Similar phenomena were observed when gliadin was supplemented to gluten powders. Basic and acidic conditions were applied to the acid- and ammonia-treated gluten powders, respectively, and the viscoelastic behaviors were found to depend on the pH in the gluten dispersion just before lyophilization. These behaviors suggest that gluten may assume a reversible change in viscoelasticity by a fluctuation in pH during gluten dispersion. SDS-PAGE showed that the extractable proteins substantially increased in some polymeric glutenins including the low molecular weight-glutenin subunit (LMW-GS) when the ammonia-treated gluten powder was extracted with 70% ethanol. In contrast, the extractable proteins markedly increased in many polymeric glutenins including the high molecular weight-glutenin subunit and/or the LMW-GS when the acid-treated gluten powder was extracted with 70% ethanol. It thus follows that the extractability of polymeric glutenin to ethanol increases similarly to gliadin when gluten is exposed to an acidic or a basic pH condition; therefore, glutenin adopts gliadin-like characteristics.

  9. Simultaneous removal of acid green 25 and mercury ions from aqueous solutions using glutamine modified chitosan magnetic composite microspheres.

    PubMed

    Tao, Xue; Li, Kun; Yan, Han; Yang, Hu; Li, Aimin

    2016-02-01

    In this current work, the magnetic composite microsphere containing glutamine modified chitosan and silica coated Fe3O4 nanoparticles (CS-Gln-MCM) has been successfully prepared and extensively characterized, which is a kind of biodegradable materials. CS-Gln-MCM shows enhanced removal efficiency for both acid green 25 (AG25), an amphoteric dye, and mercury ions (Hg(2+)) from water in the respective while measured pH range compared with chitosan magnetic composite microsphere (CS-MCM) without modification. It is due to the fact that the grafted amino acid provides a variety of additional adsorption active sites and diverse adsorption mechanisms are involved. In AG25 and Hg(2+) aqueous mixture, the modified adsorbents bear preferential adsorption for AG25 over Hg(2+) in strong acidic solutions ascribed to multiple interactions between AG25 and CS-Gln-MCM, such as hydrogen bonding and electrostatic interactions. While, in weak acidic conditions, an efficient simultaneous removal is observed for different adsorption effects involved in aforementioned two pollutants. Besides, CS-Gln-MCM illuminates not only short equilibrium time for adsorption of each pollutant less than 20.0 min but also rapid magnetic separation from water and efficient regeneration after saturated adsorption. Therefore, CS-Gln-MCM bears great application potentials in water treatment. PMID:26618263

  10. Simultaneous removal of acid green 25 and mercury ions from aqueous solutions using glutamine modified chitosan magnetic composite microspheres.

    PubMed

    Tao, Xue; Li, Kun; Yan, Han; Yang, Hu; Li, Aimin

    2016-02-01

    In this current work, the magnetic composite microsphere containing glutamine modified chitosan and silica coated Fe3O4 nanoparticles (CS-Gln-MCM) has been successfully prepared and extensively characterized, which is a kind of biodegradable materials. CS-Gln-MCM shows enhanced removal efficiency for both acid green 25 (AG25), an amphoteric dye, and mercury ions (Hg(2+)) from water in the respective while measured pH range compared with chitosan magnetic composite microsphere (CS-MCM) without modification. It is due to the fact that the grafted amino acid provides a variety of additional adsorption active sites and diverse adsorption mechanisms are involved. In AG25 and Hg(2+) aqueous mixture, the modified adsorbents bear preferential adsorption for AG25 over Hg(2+) in strong acidic solutions ascribed to multiple interactions between AG25 and CS-Gln-MCM, such as hydrogen bonding and electrostatic interactions. While, in weak acidic conditions, an efficient simultaneous removal is observed for different adsorption effects involved in aforementioned two pollutants. Besides, CS-Gln-MCM illuminates not only short equilibrium time for adsorption of each pollutant less than 20.0 min but also rapid magnetic separation from water and efficient regeneration after saturated adsorption. Therefore, CS-Gln-MCM bears great application potentials in water treatment.

  11. Phytochemical Composition and Anti-Inflammatory Activity of Extracts from the Whole-Meal Flour of Italian Durum Wheat Cultivars

    PubMed Central

    Laddomada, Barbara; Durante, Miriana; Minervini, Fiorenza; Garbetta, Antonella; Cardinali, Angela; D’Antuono, Isabella; Caretto, Sofia; Blanco, Antonio; Mita, Giovanni

    2015-01-01

    In this study, the quali-quantitative composition of hydrophilic (phenolic acids) and lipophilic (isoprenoids) extracts from whole-meal flour of five elite Italian durum wheat cultivars was determined. Significant differences in the content of bioactive compounds were observed among the wheat extracts, in particular concerning the content of bound phenolic acids, lutein and β-tocotrienols. The cultivars Duilio and Svevo showed the highest amount of phenolic acids and isoprenoids, respectively. Extracts were evaluated for their anti-inflammatory activity on HT-29 human colon cells by measuring the levels of interleukin 8 (IL-8) and transforming growth factor β1 (TGF-β1). Durum wheat extracts significantly inhibited the secretion of the pro-inflammatory IL-8 mediator at 66 µg/mL of phenolic acids and at 0.2 µg/mL of isoprenoids. Conversely, the secretion of the anti-inflammatory mediator TGF-β1 was not modified by neither hydrophilic nor lipophilic extracts. These results provide further insight into the potential of durum wheat on human health suggesting the significance of varieties with elevated contents of bioactive components. PMID:25658801