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Sample records for acid hydrolysis monosaccharide

  1. Quantitative Prediction of Cell Wall Polysaccharide Composition in Grape (Vitis vinifera L.) and Apple (Malus domestica) Skins from Acid Hydrolysis Monosaccharide Profiles

    Arnous, Anis; Meyer, Anne S.

    2009-01-01

    On the basis of monosaccharide analysis after acid hydrolysis of fruit skin samples of three wine grape cultivars, Vitis vinifera L. Cabernet Sauvignon, Merlot, and Shiraz, and of two types of apple, Malus domestica Red Delicious and Golden Delicious, an iterative calculation method is reported for...... the quantitative allocation of plant cell wall monomers into relevant structural polysaccharide elements. By this method the relative molar distribution (mol %) of the different polysaccharides in the red wine grape skins was estimated as 57-62 mol % homogalacturonan, 6.0-14 mol % cellulose, 10-11 mol......-47% by weight of the skins (dry matter), the rest mainly being lignin. The predicted relative molar levels of the polysaccharide elements in the apple skins, which made up similar to 49-64% by weight of the skins (dry matter), appeared to be similar to those of the grape skins. The apple skins were...

  2. Kinetics of Sawdust Hydrolysis with Dilute Hydrochloric Acid and Ferrous Chloride

    袁传敏; 颜涌捷; 任铮伟; 李庭琛; 曹建勤

    2004-01-01

    With dilute hydrochloric acid as catalyst and promoted by ferrous chloride, hydrolysis of waste sawdust to produce monosaccharides was conducted by using an one-step method in a batch-wise operation reactor. Based on the model of first order consecutive irreversible reactions, the kinetics equation incorporating the term of catalyst concentration was obtained that is suitable for describing the hydrolysis of sawdust. Activation energies were calculated for hydrolysis of sawdust and decomposition of monosaccharides.

  3. Production of monosaccharides from napier grass by hydrothermal process with phosphoric acid.

    Takata, Eri; Tsutsumi, Ken; Tsutsumi, Yuji; Tabata, Kenji

    2013-09-01

    The production of monosaccharides from napier grass was investigated in the presence of acid catalysts using the hydrothermal process. When the napier grass was treated with 3 wt.% phosphoric acid at 160°C for 15min, the xylose yield reached 10.3 wt.%, corresponding to 72.0% of the xylan in it, whereas glucose was hardly obtained. A combined process was then conducted using an 85 wt.% phosphoric acid treatment at 60 °C for 1h followed by a hydrothermal treatment with 3 wt.% phosphoric acid. In the initial treatment with concentrated phosphoric acid the most of xylan was hydrolyzed to xylose, and the crystalline cellulose was converted to its amorphous form. The hydrolysis of cellulose to glucose was significantly enhanced during the following hydrothermal process with 3 wt.% phosphoric acid at 200 °C for 8 min. Consequently, 77.2% yield of xylose and 50.0% yield of glucose were obtained from the combined process. PMID:23777845

  4. APPLICATION OF A PSEUDO-KINETIC GENERALIZED SEVERITY MODEL TO THE CONCENTRATED SULFURIC ACID HYDROLYSIS OF PINEWOOD AND ASPENWOOD

    Kando K. Janga,

    2012-05-01

    Full Text Available The yield of monosaccharides after two-stage concentrated sulfuric acid hydrolysis of softwood (Scots pine and hardwood (trembling aspen was modeled using a generalized severity parameter with a time-independent rate constant. The severity parameter, which combines the major operating variables acid concentration, temperature, and reaction time in the decrystallization stage into a single reaction ordinate, was successfully used to describe monosaccharide yields after a standardized hydrolysis stage. Conversion of cellulose to glucose demanded a higher severity to reach maximum glucose yields than the conversion of hemicelluloses to their respective monosaccharides, and the conversion of pine demanded a higher severity to obtain maximum monosaccharide yields as compared to aspen. The results indicate that the generalized severity parameter can be a useful tool for the prediction of sugar yields in a two-stage concentrated sulfuric acid hydrolysis process.

  5. APPLICATION OF A PSEUDO-KINETIC GENERALIZED SEVERITY MODEL TO THE CONCENTRATED SULFURIC ACID HYDROLYSIS OF PINEWOOD AND ASPENWOOD

    Kando K. Janga,; Karin Øyaas,; Terje Hertzberg; Størker T Moe

    2012-01-01

    The yield of monosaccharides after two-stage concentrated sulfuric acid hydrolysis of softwood (Scots pine) and hardwood (trembling aspen) was modeled using a generalized severity parameter with a time-independent rate constant. The severity parameter, which combines the major operating variables acid concentration, temperature, and reaction time in the decrystallization stage into a single reaction ordinate, was successfully used to describe monosaccharide yields after a standardized hydroly...

  6. Fate of microbial nitrogen, carbon, hydrolysable amino acids, monosaccharides, and fatty acids in sediment

    Veuger, Bart; van Oevelen, Dick; Middelburg, Jack J.

    2012-04-01

    The fate of microbial carbon, nitrogen, hydrolysable amino acids (HAAs), monosaccharides, and fatty acids in sediment was investigated experimentally. The microbial community of a tidal flat sediment was labeled with 13C-enriched glucose and 15N-enriched ammonium, and sediment was incubated for up to 371 days. Analysis of total concentrations and 13C- and 15N content of bulk sediment, hydrolysable amino acids (including D-alanine), monosaccharides, total fatty acids (TFAs), and phospholipid-derived fatty acids (PLFAs) allowed us to trace the fate of microbial biomass and -detritus and the major biochemical groups therein (proteins, carbohydrates, and lipids) over intermediate time scales (weeks-months). Moreover, the unidentified fraction of the labeled material (i.e. not analyzed as HAA, FA, or carbohydrate) provided information on the formation and fate of molecularly uncharacterizable organic matter. Loss of 13C and 15N from the sediment was slow (half live of 433 days) which may have been due to the permanently anoxic conditions in the experiment. Loss rates for the different biochemical groups were also low with the following order of loss rate constants: PLFA > TFA > HAA > monosaccharides. The unidentified 13C-pool was rapidly formed (within days) and then decreased relatively slowly, resulting in a gradual relative accumulation of this pool over time. Degradation and microbial reworking of the labeled material resulted in subtle, yet consistent, diagenetic changes within the different biochemical groups. In the HAA pool, glycine, lysine, and proline were lost relatively slowly (i.e. best preserved) while there was no accumulation of D-alanine relative to L-alanine, indicating no relative accumulation of bacterial macromolecules rich in D-alanine. In the fatty acid pool, there was very little difference between PLFAs and TFAs, indicating a very similar lability of these pools. Differences between individual fatty acids included a relatively slow loss of i15

  7. Evaluation of hyper thermal acid hydrolysis of Kappaphycus alvarezii for enhanced bioethanol production.

    Ra, Chae Hun; Nguyen, Trung Hau; Jeong, Gwi-Taek; Kim, Sung-Koo

    2016-06-01

    Hyper thermal (HT) acid hydrolysis of Kappaphycus alvarezii, a red seaweed, was optimized to 12% (w/v) seaweed slurry content, 180mM H2SO4 at 140°C for 5min. The maximum monosaccharide concentration of 38.3g/L and 66.7% conversion from total fermentable monosaccharides of 57.6g/L with 120gdw/L K. alvarezii slurry were obtained from HT acid hydrolysis and enzymatic saccharification. HT acid hydrolysis at a severity factor of 0.78 efficiently converted the carbohydrates of seaweed to monosaccharides and produced a low concentration of inhibitory compounds. The levels of ethanol production by separate hydrolysis and fermentation with non-adapted and adapted Kluyveromyces marxianus to high concentration of galactose were 6.1g/L with ethanol yield (YEtOH) of 0.19 at 84h and 16.0g/L with YEtOH of 0.42 at 72h, respectively. Development of the HT acid hydrolysis process and adapted yeast could enhance the overall ethanol fermentation yields of K. alvarezii seaweed. PMID:26950757

  8. Kinetics of the hydrolysis of polysaccharide galacturonic acid and neutral sugars chains from flaxseed mucilage

    Happi Emaga, T.; Rabetafika, N.; Blecker, CS.; Paquot, M.

    2012-01-01

    Different hydrolysis procedures of flaxseed polysaccharides (chemical and enzymatic) were carried out with H2SO4, HCl and TFA at different acid concentrations (0.2, 1 and 2 M) and temperatures (80 and 100°C). Enzymatic and combined chemical and enzymatic hydrolyses of polysaccharide from flaxseed mucilage were also studied. Acid hydrolysis conditions (2 M H2SO4, 4 h, 100°C) are required to quantify total monosaccharide content of flaxseed mucilage. The enzymatic pathway (Pectinex™ Ultra SP) l...

  9. Separation of phenolic acids from monosaccharides by low-pressure nanofiltration integrated with laccase pre-treatments

    Luo, Jianquan; Zeuner, Birgitte; Morthensen, Sofie Thage;

    2015-01-01

    Separation of phenolic acids from monosaccharides is required for detoxification of lignocellulosic hydrolysates. For the first time, a low-pressure nanofiltration (NF) process was used to retain phenolic acids (vanillic acid, p-coumaric acid and ferulic acid) and at the same time permeate...

  10. Production and recovery of monosaccharides from lignocellulose hot water extracts in a pulp mill biorefinery.

    Sainio, Tuomo; Kallioinen, Mari; Nakari, Olli; Mänttäri, Mika

    2013-05-01

    Processing of hemicelluloses obtained with pressurized hot water extraction (PHWE) from Scots pine to monosaccharides and other chemicals was investigated experimentally. A process scheme consisting of ultrafiltration, acid hydrolysis, and chromatographic separation was proposed and evaluated. A two-stage ultrafiltration was found necessary for efficient fractionation of the wood extract. It was shown that the monosaccharides can be released from a concentrated hemicellulose fraction with sulfuric acid hydrolysis without a significant loss of yield due to decomposition of monosaccharides. Acid hydrolysate was successfully fractionated with ion exchange chromatography and the hydrolysis acid was recovered for reuse. The product fractions obtained include polyphenols and high molar mass hemicelluloses (from UF stage 1), arabinose (from UF stage 2), as well as acetic acid and a mixture of monosaccharides (xylose, galactose, mannose, glucose) from chromatography. PMID:23069608

  11. Hemicellulose hydrolysis catalysed by solid acids

    P.D.. Carà; M. Pagliaro; A. Elmekawy; D.R. Brown; P. Verschuren; N.R. Shiju; G. Rothenberg

    2013-01-01

    Depolymerising hemicellulose into platform sugar molecules is a key step in developing the concept of an integrated biorefinery. This reaction is traditionally catalysed by either enzymes or homogeneous mineral acids. We compared various solid catalysts for hemicellulose hydrolysis, running reaction

  12. Kinetics of the hydrolysis of polysaccharide galacturonic acid and neutral sugars chains from flaxseed mucilage

    Happi Emaga, T.

    2012-01-01

    Full Text Available Different hydrolysis procedures of flaxseed polysaccharides (chemical and enzymatic were carried out with H2SO4, HCl and TFA at different acid concentrations (0.2, 1 and 2 M and temperatures (80 and 100°C. Enzymatic and combined chemical and enzymatic hydrolyses of polysaccharide from flaxseed mucilage were also studied. Acid hydrolysis conditions (2 M H2SO4, 4 h, 100°C are required to quantify total monosaccharide content of flaxseed mucilage. The enzymatic pathway (Pectinex™ Ultra SP limits sugar destruction during hydrolysis, but it is also insufficient for complete depolymerization. The combination of the two treatments, i.e. moderate chemical hydrolysis (0.2 M H2SO4, 80°C, 48 h combined with enzymatic hydrolysis is not more effective compared to chemical hydrolysis in drastic conditions (2 M H2SO4 at 100°C. The strong interaction between the neutral and acid fractions of flaxseed mucilage may hinder total release of sugar residues. Physical treatment prior to the hydrolysis could be necessary to achieve complete depolymerisation of flaxseed mucilage.

  13. Experimental study and product analysis of lignocellulosic biomass hydrolysis under extremely low acids

    Shurong WANG; Xinshu ZHUANG; Zhongyang LUO; Kefa CEN

    2008-01-01

    Using our self-designed facility for lignocellulo-sic biomass hydrolysis under extremely low acid, and under the optimal reaction conditions of hemicellulose and cel-lulose determined by xylan and quantitative filter paper as the model, two-step dilute acid hydrolysis was carried out in detail on pine, fast-growing poplar and maize straw. The corresponding conversion ratio is 41.78%, 57.84% and 53.44% and the total reducing sugar conversion ratio is 39.28%, 42.83% and 23.82% respectively. Simultaneously, sugar component analysis of the products was performed by high performance liquid chromatography (HPLC) and monosaccharide and oligosaccharide content were com-pared. Finally, poplar hydrolysis residues were analyzed by proximate and ultimate analysis.

  14. Mechanisms of lactone hydrolysis in acidic conditions.

    Gómez-Bombarelli, Rafael; Calle, Emilio; Casado, Julio

    2013-07-19

    The acid-catalyzed hydrolysis of linear esters and lactones was studied using a hybrid supermolecule-polarizable continuum model (PCM) approach including up to six water molecules. The compounds studied included two linear esters, four β-lactones, two γ-lactones, and one δ-lactone: ethyl acetate, methyl formate, β-propiolactone, β-butyrolactone, β-isovalerolactone, diketene (4-methyleneoxetan-2-one), γ-butyrolactone, 2(5H)-furanone, and δ-valerolactone. The theoretical results are in good quantitative agreement with the experimental measurements reported in the literature and also in excellent qualitative agreement with long-held views regarding the nature of the hydrolysis mechanisms at molecular level. The present results help to understand the balance between the unimolecular (A(AC)1) and bimolecular (A(AC)2) reaction pathways. In contrast to the experimental setting, where one of the two branches is often occluded by the requirement of rather extreme experimental conditions, we have been able to estimate both contributions for all the compounds studied and found that a transition from A(AC)2 to A(AC)1 hydrolysis takes place as acidity increases. A parallel work addresses the neutral and base-catalyzed hydrolysis of lactones. PMID:23731203

  15. Microwave-assisted Weak Acid Hydrolysis of Proteins

    Miyeong Seo

    2012-06-01

    Full Text Available Myoglobin was hydrolyzed by microwave-assisted weak acid hydrolysis with 2% formic acid at 37 oC, 50 oC, and100 oC for 1 h. The most effective hydrolysis was observed at 100 oC. Hydrolysis products were investigated using matrixassistedlaser desorption/ionization time-of-flight mass spectrometry. Most cleavages predominantly occurred at the C-termini ofaspartyl residues. For comparison, weak acid hydrolysis was also performed in boiling water for 20, 40, 60, and 120 min. A 60-min weak acid hydrolysis in boiling water yielded similar results as a 60-min microwave-assisted weak acid hydrolysis at100 oC. These results strongly suggest that microwave irradiation has no notable enhancement effect on acid hydrolysis of proteinsand that temperature is the major factor that determines the effectiveness of weak acid hydrolysis.

  16. ACID HYDROLYSIS OF HEMICELLULOSE FROM SUGARCANE BAGASSE

    A. PESSOA JR.

    1997-09-01

    Full Text Available Hydrolysis of the hemicellulosic fraction of sugarcane bagasse by sulphuric acid was performed in laboratory (25 mL and semi-pilot (25 L reactors under different conditions of temperature, time and acid concentration. On the laboratory scale, the three highest recovery yields were obtained at: 140ºC for 10 min with 100 mgacid/gdm (yield=73.4%; 140ºC for 20 min with 100 mgacid/gdm (yield=73.9% and 150ºC for 20 min with 70 mgacid/gdm (yield=71.8%. These conditions were also used for hydrolysis in a semi-pilot reactor, and the highest xylose recovery yield (83.3% was obtained at 140ºC for 20 min with 100 mgacid/gdm

  17. Hemicellulose hydrolysis catalysed by solid acids

    Carà, P.D..; Pagliaro, M.; Elmekawy, A.; Brown, D R; Verschuren, P.; Shiju, N.R.; Rothenberg, G.

    2013-01-01

    Depolymerising hemicellulose into platform sugar molecules is a key step in developing the concept of an integrated biorefinery. This reaction is traditionally catalysed by either enzymes or homogeneous mineral acids. We compared various solid catalysts for hemicellulose hydrolysis, running reactions in water, under neutral pH and relatively mild temperature and pressure (120 degrees C and 10 bar) conditions. Sulphonated resins are highly active, but they leach out sulphonic groups. Sulphonat...

  18. Sulfonic acid heterogeneous catalysts for dehydration of C6-monosaccharides to 5-hydroxymethylfurfural in dimethyl sulfoxide

    Gabriel Morales; Juan A.Melero; Marta Paniagua; Jose Iglesias; Blanca Hernández; María Sanz

    2014-01-01

    Sulfonic acid-functionalized heterogeneous catalysts have been evaluated in the catalytic dehydra-tion of C6 monosaccharides into 5-hydroxymethylfurfural (HMF) using dimethyl sulfoxide (DMSO) as solvent. Sulfonic commercial resin Amberlyst-70 was the most active catalyst, which was as-cribed to its higher concentration of sulfonic acid sites as compared with the other catalysts, and it gave 93 mol%yield of HMF from fructose in 1 h. With glucose as the starting material, which is a much more difficult reaction, the reaction conditions (time, temperature, and catalyst loading) were optimized for Amberlyst-70 by a response surface methodology, which gave a maximum HMF yield of 33 mol%at 147°C with 23 wt%catalyst loading based on glucose and 24 h reaction time. DMSO promotes the dehydration of glucose into anhydroglucose, which acts as a reservoir of the substrate to facilitate the production of HMF by reducing side reactions. Catalyst reuse without a regeneration treatment showed a gradual but not very significant decay in catalytic activity.

  19. Acid-functionalized nanoparticles for biomass hydrolysis

    Pena Duque, Leidy Eugenia

    Cellulosic ethanol is a renewable source of energy. Lignocellulosic biomass is a complex material composed mainly of cellulose, hemicellulose, and lignin. Biomass pretreatment is a required step to make sugar polymers liable to hydrolysis. Mineral acids are commonly used for biomass pretreatment. Using acid catalysts that can be recovered and reused could make the process economically more attractive. The overall goal of this dissertation is the development of a recyclable nanocatalyst for the hydrolysis of biomass sugars. Cobalt iron oxide nanoparticles (CoFe2O4) were synthesized to provide a magnetic core that could be separated from reaction using a magnetic field and modified to carry acid functional groups. X-ray diffraction (XRD) confirmed the crystal structure was that of cobalt spinel ferrite. CoFe2O4 were covered with silica which served as linker for the acid functions. Silica-coated nanoparticles were functionalized with three different acid functions: perfluoropropyl-sulfonic acid, carboxylic acid, and propyl-sulfonic acid. Transmission electron microscope (TEM) images were analyzed to obtain particle size distributions of the nanoparticles. Total carbon, nitrogen, and sulfur were quantified using an elemental analyzer. Fourier transform infra-red spectra confirmed the presence of sulfonic and carboxylic acid functions and ion-exchange titrations accounted for the total amount of catalytic acid sites per nanoparticle mass. These nanoparticles were evaluated for their performance to hydrolyze the beta-1,4 glycosidic bond of the cellobiose molecule. Propyl-sulfonic (PS) and perfluoropropyl-sulfonic (PFS) acid functionalized nanoparticles catalyzed the hydrolysis of cellobiose significantly better than the control. PS and PFS were also evaluated for their capacity to solubilize wheat straw hemicelluloses and performed better than the control. Although PFS nanoparticles were stronger acid catalysts, the acid functions leached out of the nanoparticle during

  20. Generation of organic acids and monosaccharides by hydrolytic and oxidative transformation of food processing residues.

    Fischer, Klaus; Bipp, Hans-Peter

    2005-05-01

    Carbohydrate-rich biomass residues, i.e. sugar beet molasses, whey powder, wine yeast, potato peel sludge, spent hops, malt dust and apple marc, were tested as starting materials for the generation of marketable chemicals, e.g. aliphatic acids, sugar acids and mono-/disaccharides. Residues were oxidized or hydrolyzed under acidic or alkaline conditions applying conventional laboratory digestion methods and microwave assisted techniques. Yields and compositions of the oxidation products differed according to the oxidizing agent used. Main products of oxidation by 30% HNO(3) were acetic, glucaric, oxalic and glycolic acids. Applying H(2)O(2)/CuO in alkaline solution, the organic acid yields were remarkably lower with formic, acetic and threonic acids as main products. Gluconic acid was formed instead of glucaric acid throughout. Reaction of a 10% H(2)O(2) solution with sugar beet molasses generated formic and lactic acids mainly. Na(2)S(2)O(8) solutions were very inefficient at oxidizing the residues. Glucose, arabinose and galactose were formed during acidic hydrolysis of malt dust and apple marc. The glucose content reached 0.35 g per gram of residue. Important advantages of the microwave application were lower reaction times and reduced reagent demands. PMID:15607197

  1. Monosaccharide anhydrides, monocarboxylic acids and OC/EC in PM1 aerosols in urban areas in the Czech Republic

    Křůmal, Kamil; Mikuška, Pavel; Večeřa, Zbyněk

    2015-01-01

    Roč. 6, č. 6 (2015), s. 917-927. ISSN 1309-1042 R&D Projects: GA MŽP SP/1A3/148/08; GA ČR(CZ) GBP503/12/G147; GA ČR GA13-01438S; GA ČR(CZ) GA14-25558S Institutional support: RVO:68081715 Keywords : Monosaccharide anhydrides * carboxylic acids * fatty acids * organic carbon * biomass burning Subject RIV: CB - Analytical Chemistry, Separation Impact factor: 1.371, year: 2014

  2. Weak acid hydrolysis of wood CTH. Final report; Svagsyrahydrolys av trae CTH. Slutrapport

    Linner, J.; Lundquist, K.; Ohlsson, Brita; Simonson, R. [Chalmers Univ. of Technology, Goeteborg (Sweden). Forest Products and Chemical Engineering

    1998-08-01

    Spruce wood meal was extracted with dichloromethane and used for production of holocellulose by standard delignification with sodium chlorite. The holocellulose as well as wood meal were used as substrate on hydrolysis with 0.1 or 0.5 M sulfuric acid at a substrate concentration of 5%. The hydrolysis trials were carried out in teflon containers that were rapidly heated to the reaction temperature (100 - 170 deg C) by means of microwaves. Reaction times of up to 4 hrs were used. The results showed that 80% of the polysaccharides in spruce wood meal and spruce holocellulose can be hydrolyzed to soluble products within 30 min under relatively mild conditions (160-170 deg C, 0.5 M sulfuric acid). The hydrolysates contained relatively small amounts of hydroximethylfurfural and its degradation product levulinic acid. Formed xylose was rapidly converted to furfural which in its turn was rapidly further reacted to condensation products. A maximum yield of hexose amounting to about 30 g/100 g substrate was obtained after about 15 min. This amount corresponds to about one third of the available hexoses in the holocellulose. Compared to the hemicellulose, the cellulose and especially the crystalline part is difficult to hydrolyze and the hemicellulose originating monosaccharides formed at an early stage seem to be destroyed to a large extent on prolonged hydrolysis. A two-step reaction at mild conditions should therefore be examined. Residues from the wood hydrolysis experiments were examined by IR spectroscopy. The spectra clearly showed that lignin accumulated in the residues. Several of the hydrolysis residues were dark-coloured (almost black). The strongly coloured constituents originate primarily from the carbohydrates. Dark-coloured precipitates were also obtained in hydrolysis experiments with carbohydrates. The IR spectra of these precipitates exhibited strong bands in the carbonyl region. Chloroform extracts of wood hydrolysates consisted mainly of conversion

  3. Simultaneous separation and quantitative determination of monosaccharides, uronic acids, and aldonic acids by high performance anion-exchange chromatography coupled with pulsed amperometric detection in corn stover prehydrolysates

    Xing Wang

    2012-11-01

    Full Text Available A method for simultaneous separation and quantitative determination of arabinose, galactose, glucose, xylose, xylonic acid, gluconic acid, galacturonic acid, and glucuronic acid was developed by using high performance anion-exchange chromatography coupled with pulsed amperometric detection (HPAEC-PAD. The separation was performed on a CarboPacTM PA-10 column (250 mm × 2 mm with a various gradient elution of NaOH-NaOAc solution as the mobile phase. The calibration curves showed good linearity (R2 ≥ 0.9993 for the monosaccharides, uronic acids, and aldonic acids in the range of 0.1 to 12.5 mg/L. The detection limits (LODs and the quantification limits (LOQs were 4.91 to 18.75 μg/L and 16.36 to 62.50 μg/L, respectively. Relative standard deviations (RSDs of the retention times and peak areas for the seven consecutive determinations of an unknown amount of mixture were 0.15% to 0.44% and 0.22% to 2.31%, respectively. The established method was used to separate and determine four monosaccharides, two uronic acids, and two aldonic acids in the prehydrolysate from dilute acid steam-exploded corn stover within 21 min. The spiked recoveries of monosaccharides, uronic acids, and aldonic acids ranged from 91.25% to 108.81%, with RSDs (n=3 of 0.04% ~ 6.07%. This method was applied to evaluate the quantitative variation of sugar and sugar acid content in biomass prehydrolysates.

  4. Hydrolysis of Polysaccharides with 77% Sulfuric Acid for Quantitative Saccharification

    UÇAR, Güneş; Balaban, Mualla

    2003-01-01

    Classical standard hydrolysis of polysaccharides with 72% sulfuric acid was modified in 2 manners. In order to avoid treatment in an autoclave at 120 °C under pressure, wood or pulp material was first swollen in cold 77% acid followed by hydrolysis steps in diluted acid solutions. Further, the neutralization of the hydrolyzate with dilute barium hydroxide was carried out in heated mother liquor ensuring a crystalline precipitate of barium sulfate. Digestion enables the separation of clear ali...

  5. Furfural production from fruit shells by acid-catalyzed hydrolysis

    Demirbas, A. [Selcuk Univ., Konya (Turkey). Dept. of Chemical Engineering

    2006-01-21

    Pentosans are hydrolyzed to pentoses by dilute mineral acid hydrolysis. The main source of pentosans is hemicelluloses. Furfural can be produced by the acid hydrolysis of pentosan from fruit shells such as hazelnut, sunflower, walnut, and almond of agricultural wastes. Further dehydration reactions of the pentoses yield furfural. The hydrolysis of each shell sample was carried out in dilute sulfuric acid (0.05 to 0.200 mol/l), at high temperature (450-525 K), and short reaction times (from 30 to 600 s). (author)

  6. INFLUENCE OF ACID CONCENTRATION, TEMPERATURE, AND TIME ON THE CONCENTRATED SULFURIC ACID HYDROLYSIS OF PINEWOOD AND ASPENWOOD: A STATISTICAL APPROACH

    Kando K. Janga

    2011-11-01

    Full Text Available The effects on sugar yields of acid concentration, temperature, and time in the first (decrystallization stage of a two-stage concentrated sulfuric acid hydrolysis of softwood (Scots pine and hardwood (aspen were investigated. The study focused on the multi-variable effects of the decrystallization stage and applied a statistical modeling with Central Composite Face (CCF design of experiment to systematically study and simulate the effect of decrystallization reaction conditions on hydrolysis products and degradation products. The models were statistically significant and showed that for both aspen and pine, the reaction temperature and acid concentration were the most influential variables on monosaccharides and total sugar yields compared to the reaction time. The interaction between temperature and acid concentration was the most important for both species. The sugar degradation products were much influenced by the decrystallization temperature on both aspen and pine. The models were validated by a test-set and showed a good agreement between the experimental and predicted values. The optimum predicted total sugar yields were 56 g / 100 g d.w for aspen (74% theoretical and 64 g / 100 g d.w for pine (91% theoretical.

  7. Hydrolysis of isocyanic acid on SCR catalysts

    Elsener, M.; Kleemann, M.; Koebel, M. [Paul Scherrer Inst. (PSI), Villigen (Switzerland)

    1999-08-01

    Standard SCR catalysts possess high activity for the hydrolysis of HNCO and thus explain the suitability of urea as a selective reducing agent for NO{sub x}. At high space velocities HNCO-slip can get perceptible over the entire temperature range. This can be attributed to the fact that the temperature dependence is strong for the SCR reaction, but weak for the hydrolysis reaction. (author) 3 figs., 5 refs.

  8. Quantitative solid state NMR analysis of residues from acid hydrolysis of loblolly pine wood.

    Sievers, Carsten; Marzialetti, Teresita; Hoskins, Travis J C; Valenzuela Olarte, Mariefel B; Agrawal, Pradeep K; Jones, Christopher W

    2009-10-01

    The composition of solid residues from hydrolysis reactions of loblolly pine wood with dilute mineral acids is analyzed by (13)C Cross Polarization Magic Angle Spinning (CP MAS) NMR spectroscopy. Using this method, the carbohydrate and lignin fractions are quantified in less than 3h as compared to over a day using wet chemical methods. In addition to the quantitative information, (13)C CP MAS NMR spectroscopy provides information on the formation of additional extractives and pseudo lignin from the carbohydrates. Being a non-destructive technique, NMR spectroscopy provides unambiguous evidence of the presence of side reactions and products, which is a clear advantage over the wet chemical analytical methods. Quantitative results from NMR spectroscopy and proximate analysis are compared for the residues from hydrolysis of loblolly pine wood under 13 different conditions; samples were treated either at 150 degrees C or 200 degrees C in the presence of various acids (HCl, H(2)SO(4), H(3)PO(4), HNO(3) and TFA) or water. The lignin content determined by both methods differed on averaged by 2.9 wt% resulting in a standard deviation of 3.5 wt%. It is shown that solid degradation products are formed from saccharide precursors under harsh reaction conditions. These degradation reactions limit the total possible yield of monosaccharides from any subsequent reaction. PMID:19477123

  9. Kinetic study on the acid-catalyzed hydrolysis of cellulose to levulinic acid

    Girisuta, B.; Janssen, L. P. B. M.; Heeres, H. J.

    2007-01-01

    A variety of interesting bulk chemicals is accessible by the acid-catalyzed hydrolysis of cellulose. An interesting example is levulinic acid, a versatile precursor for fuel additives, polymers, and resins. A detailed kinetic study on the acid-catalyzed hydrolysis of cellulose to levulinic acid is r

  10. Acid hydrolysis of Biomass lignocellulose Onopordum nervosum Boiss

    Hydrolysis of resistant cellulose of Onopordum nervosum Boiss (thistle) to reducing sugars in dilute sulfuric acid in glass ampoules and long residence times has been studied and kinetic parameters determined. The rate of hydrolysis is similar to that of the cellulose of Douglas fir, but comparatively the effect of the acid is more pronounced than temperature. From kinetic data it can be pre ducted the yield and since it can be obtained at least 45% of the potential glucose (48% as reducing sugars) at 190 degree centigree, 1,6% acid and 6,1 min. residence time, it indicates that the continuous acid hydrolysis of thistle may be a process of commercial interest. (Author) 18 refs

  11. OPTIMIZATION STUDY OF CITRUS WASTES SACCHARIFICATION BY DILUTE ACID HYDROLYSIS

    Farid Talebnia

    2008-02-01

    Full Text Available The effect of time, acid concentration, temperature and solid concentration on dilute-acid hydrolysis of orange peels was investigated. A central composite rotatable experimental design (CCRD was applied to study the individual effects of these hydrolysis factors and also their interdependence effects. The enzymatic hydrolysis of the peels by cellulase, β-glucosidase, and pectinase enzyme resulted in 72% dissolution of the peels, including 18.7% galacturonic acid and 53.3% of a total of glucose, fructose, galactose, and arabinose. Dilute-acid hydrolysis up to 210°C was not able to hydrolyze pectin to galacturonic acid. However, the sugar polymers were hydrolyzed at relatively low temperature. The optimum results were obtained at 116°C, 0.5% sulfuric acid concentration, 6% solid fraction, and 12.9 min retention time. Under these conditions, the total sugars obtained at 41.8 g/g dry peels and 2.6% of total hexose sugars were further degraded to hydroxymethylfurfural (HMF. No furfural was detected through these experiments from decomposition of pentoses.

  12. Simultaneous hydrolysis-esterification of wet microalgal lipid using acid.

    Takisawa, Kenji; Kanemoto, Kazuyo; Kartikawati, Muliasari; Kitamura, Yutaka

    2013-12-01

    This research demonstrated hydrolysis of wet microalgal lipid and esterification of free fatty acid (FFA) using acid in one-step process. The investigation of simultaneous hydrolysis-esterification (SHE) of wet microalgal lipid was conducted by using L27 orthogonal design and the effects of water content, volume of sulphuric acid, volume of methanol, temperature and time on SHE were examined. As a result, water content was found to be the most effective factor. The effects of various parameters on fatty acid methyl ester (FAME) content and equilibrium relation between FAME and FFA were also examined under water content 80%. Equimolar amounts of sulphuric acid and hydrochloric acid showed similar results. This method has great potential in terms of biodiesel production from microalgae since no organic solvents are used. PMID:24080318

  13. Degradation of hyaluronic acid, poly- and monosaccharides, and model compounds by hypochlorite

    Hawkins, C L; Davies, Michael Jonathan

    1998-01-01

    Degradation of hyaluronic acid by oxidants such as HO. and HOCl/CIO- is believed to be important in the progression of rheumatoid arthritis. While reaction of hyaluronic acid with HO. has been investigated extensively, reaction with HOCl/ClO- is less well defined. Thus, little is known about the...... site(s) of HOCl/ClO- attack, the intermediates formed, or the mechanism(s) of polymer degradation. In this study reaction of HOCl/ClO- with amides, sugars, polysaccharides, and hyaluronic acid has been monitored by UV-visible (220-340 nm) and EPR spectroscopy. UV-visible experiments have shown that......--C bond. The nature of the radicals formed has been investigated by EPR spin trapping. Reaction of HOCl/ClO- with hyaluronic acid, chondroitin sulphates A and C, N-acetyl sugars, and amides gave novel, carbon-centered, spin adducts, the formation of which is consistent with selective initial attack at the...

  14. Acid hydrolysis of kallar grass (leptochloa fusca) for the production

    Acid hydrolysis of kallar grass (leptochloa fusca) was carried of with various concentrations of sulphuric acid, ortho phosphoric acid and hydrochloric acid to produce furfural. The study revealed that activity of various hydrolysing acids to produce furfural from kallar grass was of the following order H/sub 2/SO/sub 4/ > H/sub 3/PO/sub 4/ > HCl. Optimum yield (4.78%) of the produce was obtained when the material was digested with 19% H/sub 2/SO/sub 4/ for a period of 20 minutes. (author)

  15. Intramolecular Amide Hydrolysis in N-Methylmaleamic Acid Revisited

    2002-01-01

    The intramolecular amide hydrolysis of N-methylmaleamic acid have been revisited by use of density functional theory and inclusion of solvent effects. The results indicate that concerted reaction mechanism is favored over stepwise reaction mechanism. This is in agreement with the previous theoretical study. Sovlent effects have significant influence on the reaction barrier.

  16. Carbon-based strong solid acid for cornstarch hydrolysis

    Nata, Iryanti Fatyasari, E-mail: yanti_tkunlam@yahoo.com [Chemical Engineering Study Program, Faculty of Engineering, Lambung Mangkurat University, Jl. A. Yani Km. 36 Banjarbaru, South Kalimantan 70714 (Indonesia); Irawan, Chairul; Mardina, Primata [Chemical Engineering Study Program, Faculty of Engineering, Lambung Mangkurat University, Jl. A. Yani Km. 36 Banjarbaru, South Kalimantan 70714 (Indonesia); Lee, Cheng-Kang, E-mail: cklee@mail.ntust.edu.tw [Department of Chemical Engineering, National Taiwan University of Science and Technology, 43 Keelung Rd. Sec.4, Taipei 106, Taiwan (China)

    2015-10-15

    Highly sulfonated carbonaceous spheres with diameter of 100–500 nm can be generated by hydrothermal carbonization of glucose in the presence of hydroxyethylsulfonic acid and acrylic acid at 180 °C for 4 h. The acidity of the prepared carbonaceous sphere C4-SO{sub 3}H can reach 2.10 mmol/g. It was used as a solid acid catalyst for the hydrolysis of cornstarch. Total reducing sugar (TRS) concentration of 19.91 mg/mL could be obtained by hydrolyzing 20 mg/mL cornstarch at 150 °C for 6 h using C4-SO{sub 3}H as solid acid catalyst. The solid acid catalyst demonstrated good stability that only 9% decrease in TRS concentration was observed after five repeat uses. The as-prepared carbon-based solid acid catalyst can be an environmentally benign replacement for homogeneous catalyst. - Highlights: • Carbon solid acid was successfully prepared by one-step hydrothermal carbonization. • The acrylic acid as monomer was effectively reduce the diameter size of particle. • The solid acid catalyst show good catalytic performance of starch hydrolysis. • The solid acid catalyst is not significantly deteriorated after repeated use.

  17. Enhancement of hydrolysis of Chlorella vulgaris by hydrochloric acid.

    Park, Charnho; Lee, Ja Hyun; Yang, Xiaoguang; Yoo, Hah Young; Lee, Ju Hun; Lee, Soo Kweon; Kim, Seung Wook

    2016-06-01

    Chlorella vulgaris is considered as one of the potential sources of biomass for bio-based products because it consists of large amounts of carbohydrates. In this study, hydrothermal acid hydrolysis with five different acids (hydrochloric acid, nitric acid, peracetic acid, phosphoric acid, and sulfuric acid) was carried out to produce fermentable sugars (glucose, galactose). The hydrothermal acid hydrolysis by hydrochloric acid showed the highest sugar production. C. vulgaris was hydrolyzed with various concentrations of hydrochloric acid [0.5-10 % (w/w)] and microalgal biomass [20-140 g/L (w/v)] at 121 °C for 20 min. Among the concentrations examined, 2 % hydrochloric acid with 100 g/L biomass yielded the highest conversion of carbohydrates (92.5 %) into reducing sugars. The hydrolysate thus produced from C. vulgaris was fermented using the yeast Brettanomyces custersii H1-603 and obtained bioethanol yield of 0.37 g/g of algal sugars. PMID:26899601

  18. Heteropoly acid catalyzed hydrolysis of glycogen to glucose

    Complete conversion of glycogen to glucose is achieved by using H3PW12O40·nH2O (HPW) and H4SiW12O40·nH2O (HSiW) as catalysts for the hydrolysis under optimized hydrothermal conditions (mass fraction of catalyst 2.4%, 373 K and 2 h reaction time). The reusability of the catalyst (HPW) was demonstrated. In addition to carrying out the glycogen hydrolysis in an autoclave, other novel methods such as microwave irradiation and sonication have also been investigated. At higher mass fraction of the heteropoly acids (10.5%), glycogen could be completely converted to glucose under microwave irradiation. Sonication of an aqueous solution of glycogen in the presence of HPW and HSiW also yielded glucose. Thus, heteropoly acids are efficient, environmentally friendly and reusable catalysts for the conversion of glycogen to glucose. - Highlights: • Hydrothermal, microwave and sonication based methods of hydrolysis. • Heteropoly acids are green catalysts for glycogen hydrolysis. • Glycogen from cyanobacteria is demonstrated as a potential feedstock for glucose

  19. Carbon-based strong solid acid for cornstarch hydrolysis

    Nata, Iryanti Fatyasari; Irawan, Chairul; Mardina, Primata; Lee, Cheng-Kang

    2015-10-01

    Highly sulfonated carbonaceous spheres with diameter of 100-500 nm can be generated by hydrothermal carbonization of glucose in the presence of hydroxyethylsulfonic acid and acrylic acid at 180 °C for 4 h. The acidity of the prepared carbonaceous sphere C4-SO3H can reach 2.10 mmol/g. It was used as a solid acid catalyst for the hydrolysis of cornstarch. Total reducing sugar (TRS) concentration of 19.91 mg/mL could be obtained by hydrolyzing 20 mg/mL cornstarch at 150 °C for 6 h using C4-SO3H as solid acid catalyst. The solid acid catalyst demonstrated good stability that only 9% decrease in TRS concentration was observed after five repeat uses. The as-prepared carbon-based solid acid catalyst can be an environmentally benign replacement for homogeneous catalyst.

  20. Dilute Acid Hydrolysis of Cowpea Hulls: A Kinetic Study

    Chioma M. Onyelucheya

    2016-08-01

    Full Text Available In this study, dilute acid hydrolysis of cowpea hulls was carried out in two stages under the following conditions: pre-hydrolysis (4%v/v H2SO4, 121˚C, 30 minutes and hydrolysis ( at 10% and 15% v/v H2SO4,varied at different temperatures 150 oC, 160 oC, 170 oC and 180 oC for 2.5 hrs.. The substrate was characterized using both Fourier transform infrared spectroscopy and proximate analysis. The percentage lignocellulosic composition of the substrate was obtained for cellulose, hemicellulose and lignin as 34%, 14% and 4.7% respectively. Maximum glucose concentration of 8.09g was obtained using 10%v/v acid concentration at 170˚C after a reaction time of 90min. Saeman’s model gave a good fit for the experimental data. Activation energy for glucose formation using 10%v/v and 15%v/v H2SO4 was obtained as 38.28KJ and 82.204KJ respectively. From the results obtained it can be concluded that cowpea hulls can be converted to a useful product.

  1. Boronic acid fluorescent sensors for monosaccharide signaling based on the 6-methoxyquinolinium heterocyclic nucleus: progress toward noninvasive and continuous glucose monitoring.

    Badugu, Ramachandram; Lakowicz, Joseph R; Geddes, Chris D

    2005-01-01

    The synthesis, characterization, and spectral properties of strategically designed boronic acid containing fluorescent sensors, o-, m-, p-BMOQBA, for the potential detection of tear glucose concentrations when immobilized in plastic disposable contact lenses is described. The new probes, BMOQBAs, consist of the 6-methoxyquinolinium nucleus as a fluorescent indicator, and the boronic acid moiety as a glucose chelating group. A control compound BMOQ, which has no boronic acid group and therefore does not bind monosaccharides has also been prepared. In this paper, we show that structural design considerations of the new probes have afforded for their compatibility within the lenses, with reduced probe sugar-bound pK(a) favorable with the mildly acidic lens environment. In addition, the new probes are readily water soluble, have high quantum yields, and can be prepared by a simple one-step synthetic procedure. PMID:15582456

  2. Acid hydrolysis and carbohydrates characterization of coffee pulp

    Urbaneja, G. [Universidad de los Andes, Trujillo (Venezuela). Nucleo Universitario Rafael Rangel; Ferrer, J.; Paez, G. [Universidad del Zulia, Maracaibo (Venezuela). Facultad de Ingenieria; Arenas, L.; Colina, G. [Universidad del Zulia, Marcaibo (Venezuela). Facultad de Agronomia

    1996-09-01

    Hydrolysis of coffee pulp with diluted sulfuric acid was studied by keeping boiling temperature with reflux, a liquid to solid ratio of 10:1 and a particle size {<=} 1.00 mm. Coffee pulp was treated using several acid concentration (C) and retention times (t). The hydrolysates were analyzed for total sugars by phenol-sulfuric acid and HPLC (TSPA and TSHPLC), reducing sugar (RS) by DNS and individual sugars by HPLC. Data were analyzed by using the Statistical Analysis System (SAS). The average sugar yields were: TSHPLC between 12.87-20.31% and 14.02-19.01%; TSPA between 23.41-19.07% and 25.74-30.58%; RS between 10.24-19.07% and 9.66-17.80% for (C) y (t) respectively, expressed as wt% of dry coffee pulp. The general range of variations for individual sugars was: xylose from 0.08 to 3.23; arabinose from 0.23 to 11.26; fructose from 0.90 to 3.00 and glucose from 1.30 to 6.31, expressed in gl{sup -1}. The sucrose varied between 0.08 and 3.96 and maltose between 0.01 and 3.50, also expressed in gl{sup -1} of hydrolysate. The overall efficiency of hydrolysis was 64% for TSPA and 67% for RS. (Author)

  3. Enzymatic hydrolysis of sugarcane bagasse pretreated with acid or alkali

    Vivian Cristina Pietrobon

    2011-04-01

    Full Text Available The aim of this study was to evaluate the performance of enzymatic hydrolysis of acid or alkali pretreated sugarcane bagasse for the production of fermentable sugars. The first step consisted of selection of commercial enzymes presenting the highest cellulolytic activities. After selection of four enzymes: HPL, CL, P1 and P4, their performances were tested in the bagasse pretreated with acid and alkali. The sugar content of the hydrolysates was analyzed by anion exchange liquid chromatography. Data showed that the joint action of 0.5% acid pretreatment, 121ºC, 30 minutes and enzyme CL provides the best results, 67.25 g of hexose and 148.13g of pentose per kg of dry bagasse.

  4. Conversion of rice straw to sugars by dilute-acid hydrolysis

    Hydrolysis of rice straw by dilute sulfuric acid at high temperature and pressure was investigated in one and two stages. The hydrolyses were carried out in a 10-l reactor, where the hydrolysis retention time (3-10 min), pressure (10-35 bar) and acid concentration (0-1%) were examined. Optimization of first stage hydrolysis is desirable to achieve the highest yield of the sugars from hemicellulose and also as a pretreatment for enzymatic hydrolysis. The results show the ability of first stage hydrolysis to depolymerize xylan to xylose with a maximum yield of 80.8% at hydrolysis pressure of 15 bar, 10 min retention time and 0.5% acid concentration. However, the yield of glucose from glucan was relatively low in first stage hydrolysis at a maximum of 25.8%. The solid residuals were subjected to further dilute-acid hydrolysis in this study. This second-stage hydrolysis without addition of the acid could not increase the yield of glucose from glucan beyond 26.6%. On the other hand, the best results of the hydrolysis were achieved, when 0.5% sulfuric acid was added prior to each stage in two-stage hydrolysis. The best results of the second stage of the hydrolysis were achieved at the hydrolysis pressure and the retention time of 30 bar and 3 min in the second stage hydrolysis, where a total of 78.9% of xylan and 46.6% of glucan were converted to xylose and glucose, respectively in the two stages. Formation of furfural and HMF were functions of the hydrolysis pressure, acid concentration, and retention time, whereas the concentration of acetic acid was almost constant at pressure of higher than 10 bar and a total retention time of 10 min

  5. The Crystalline Changes of Starch from Rhizoma Dioscorea by Acid Hydrolysis

    Shu Jun WANG; Wen Yuan GAO; Jing Lin YU; Pei Gen XIAO

    2006-01-01

    The changes in crystalline properties of starch from Rhizoma Dioscorea by acid hydrolysis was characterized by X-Ray diffractometry (XRD). The results revealed that the crystalline type of Rhizoma Dioscorea starch changed from C-type to A-type after 16 days of the acid hydrolysis. This phenomenon was different from that of other starches subjected to the acid hydrolysis. The results revealed that the B-polymorphs of C-type starch constituted the amorphous regions while the crystalline areas were mainly composed of A-polymorphs. The degree of crystallinity of the acid-thinned starch increased gradually with the time of acid hydrolysis.

  6. Production of reducing sugar from oil palm empty fruit bunch (EFB) cellulose fibres via acid hydrolysis

    Siew Xian Chin; Chin Hua Chia; Sarani Zakaria

    2013-01-01

    Cellulosic fibre of oil palm empty fruit bunches (EFB) were used as a raw material for acid hydrolysis using mineral acids (H2SO4 and HCl) to produce reducing sugar at moderate temperature and atmospheric pressure. Experiments were carried out to investigate the effect of the hydrolysis parameters, including acid concentration, temperature, and reaction time, on the total reducing sugar (TRS) yield with the aid of response surface methodology (RSM). The preliminary hydrolysis studies of the E...

  7. Simulation of acid hydrolysis of lignocellulosic residues to fermentable sugars for bioethanol production

    Sidiras, Dimitris

    2012-12-01

    The dilute acid hydrolysis of fir sawdust with sulfuric acid was undertaken in a batch reactor system (autoclave). The experimental data and reaction kinetic analysis indicate that this is a potential process for cellulose and hemicelluloses hydrolysis, due to a rapid hydrolysis reaction for acid concentration 0.045 N at 160-180°C. It was found that significant sugar degradation occurred at these conditions. The optimum conditions gave a yield of 38% total fermentable sugars. The kinetics of dilute acid hydrolysis of cellulose and hemicelluloses (polysaccharides) were simulated using four pseudo-kinetic models. The reaction rate constants were calculated in each case.

  8. Hydrolysis of dilute acid-pretreated cellulose under mild hydrothermal conditions.

    Chimentão, R J; Lorente, E; Gispert-Guirado, F; Medina, F; López, F

    2014-10-13

    The hydrolysis of dilute acid-pretreated cellulose was investigated in a conventional oven and under microwave heating. Two acids--sulfuric and oxalic--were studied. For both hydrothermal conditions (oven and microwave) the resultant total organic carbon (TOC) values obtained by the hydrolysis of the cellulose pretreated with sulfuric acid were higher than those obtained by the hydrolysis of the cellulose pretreated with oxalic acid. However, the dicarboxylic acid exhibited higher hydrolytic efficiency towards glucose. The hydrolysis of cellulose was greatly promoted by microwave heating. The Rietveld method was applied to fit the X-ray patterns of the resultant cellulose after hydrolysis. Oxalic acid preferentially removed the amorphous region of the cellulose and left the crystalline region untouched. On the other hand, sulfuric acid treatment decreased the ordering of the cellulose by partially disrupting its crystalline structure. PMID:25037336

  9. A Long-Wavelength Fluorescent Squarylium Cyanine Dye Possessing Boronic Acid for Sensing Monosaccharides and Glycoproteins with High Enhancement in Aqueous Solution

    Hiroyuki Nakazumi

    2012-04-01

    Full Text Available Fluorescence sensing of saccharides and glycoproteins using a boronic acid functionalized squarylium cyanine dye (“SQ-BA” is characterized in terms of synthetic, fluorometric, thermodynamic and kinetic parameters. In our previous work, this newly synthesized dye was successfully applied to the separation and quantification of Gram-positive bacteria by capillary electrophoresis with laser-induced fluorescence detection (CE-LIF; however, the fundamental properties of the dye and its saccharide complexes still required elucidation, as presented in this paper. The dye itself forms nonemissive, soluble aggregates in aqueous solution. With the addition of a monosaccharide, the dye aggregate dissociates to form an emissive monomer accompanied by the formation of a cyclic cis-diol ester with long-wavelength emission (lex = 630 nm, lem = 660 nm. A very large fluorescence enhancement factor of 18× was observed for the sensing dye as a fructose complex at pH 10, yielding a limit of detection of 10 mM fructose. The relative order of fluorescence enhancement of SQ-BA with other monosaccharides was found to be: fructose > ribose > arabinose ≈ galactose > xylose > mannose > rhamnose > fucose ≈ glucose; and apparent affinity constants of 102.80, 102.08 and 100.86 M−1 were determined for fructose, ribose and glucose, respectively. Formation of the emissive complexes occurred within minutes, proving the kinetics of the sugar-dye interactions to be suitable for on-column labeling methods in CE-LIF. Furthermore, the sensing dye was successfully applied to glycoproteins, mucin type I–S and type III, which were detected with high sensitivity in batch aqueous solution as a result of the sugar-selective boronic acid-diol esterification as well as hydrophobic interactions.

  10. A Long-Wavelength Fluorescent Squarylium Cyanine Dye Possessing Boronic Acid for Sensing Monosaccharides and Glycoproteins with High Enhancement in Aqueous Solution

    Saito, Shingo; Massie, Tara L.; Maeda, Takeshi; Nakazumi, Hiroyuki; Colyer, Christa L.

    2012-01-01

    Fluorescence sensing of saccharides and glycoproteins using a boronic acid functionalized squarylium cyanine dye (“SQ-BA”) is characterized in terms of synthetic, fluorometric, thermodynamic and kinetic parameters. In our previous work, this newly synthesized dye was successfully applied to the separation and quantification of Gram-positive bacteria by capillary electrophoresis with laser-induced fluorescence detection (CE-LIF); however, the fundamental properties of the dye and its saccharide complexes still required elucidation, as presented in this paper. The dye itself forms nonemissive, soluble aggregates in aqueous solution. With the addition of a monosaccharide, the dye aggregate dissociates to form an emissive monomer accompanied by the formation of a cyclic cis-diol ester with long-wavelength emission (λex = 630 nm, λem = 660 nm). A very large fluorescence enhancement factor of 18× was observed for the sensing dye as a fructose complex at pH 10, yielding a limit of detection of 10 μM fructose. The relative order of fluorescence enhancement of SQ-BA with other monosaccharides was found to be: fructose > ribose > arabinose ≈ galactose > xylose > mannose > rhamnose > fucose ≈ glucose; and apparent affinity constants of 102.80, 102.08 and 100.86 M−1 were determined for fructose, ribose and glucose, respectively. Formation of the emissive complexes occurred within minutes, proving the kinetics of the sugar-dye interactions to be suitable for on-column labeling methods in CE-LIF. Furthermore, the sensing dye was successfully applied to glycoproteins, mucin type I–S and type III, which were detected with high sensitivity in batch aqueous solution as a result of the sugar-selective boronic acid-diol esterification as well as hydrophobic interactions. PMID:22778592

  11. Vitamin B2 content determination in liver paste by using acid and acid-enzyme hydrolysis

    Basić Zorica

    2007-01-01

    Full Text Available Background/Aim. Vitamin B2 is available in foodstuff in the form of coenzyme and in free form. For its content determination a few procedures should be performed (deliberation from a complex, extraction of free and deliberated form and detection, identification and quantification. There is a particular problem in determination of vitamin B2 in the meat products. For a determination of total vitamin B2 content in liver paste two preparation procedures are compared: acid and acid-enzymatic hydrolysis. The aim of this study thus, was to compare the effectiveness of these two different procedures for vitamin B2 content determination in liver paste. Methods. High pressure liquid chromatography (HPLC method with fluorescence detector, as specific and adequately sensitive for the foodstuff of a complex composition with a natural vitamin content, was used for determination of vitamin B2 in liver paste. Acid hydrolysis was performed with the application 0.1 M hydrochloric acid in a pressure cooker, and enzymatic hydrolysis was performed with the 10% takadiastase on 45 ºC within four hours. Ten samples of liver paste from the supply of the Serbian Army were examined. Separation was performed on the analytical column Nucleosil 50−5 C18 with mobile phase 450 ml CH3OH + 20 ml 5 mM CH3COONH4, and detection on the fluorescent detector with the variable wave length. Both methods were validated: examining a detection limit, quantification limit, specificity (because of a possible B2 vitamin interference with reagents, linearity of a peak area and standard concentration of B2 vitamin ratio in the range from 0.05 μg/ml to 2 μg/ml, precision for the 0.05 μg/ml concentration and recovery. Results. All the previously examined parameters validated both methods as specific, precise and reproductive, with a high recovery (98.5% for acid and 98.2% for acid - enzymatic hydrolysis, as well as linearity in a range that significantly superseded the expected content in

  12. Study on the Hydrolysis Kinetics of Xylan on Different Acid Catalysts

    In this study, we investigated kinetic model for the acid-catalyzed xylan hydrolysis at temperature 120-150 .deg. C. Also, we analyzed the kinetic parameters for xylose production and furfural decomposition. The hydrolysis of xylan and the degradation of xylose were promoted by high reaction temperature and acid concentration. The optimal hydrolysis condition for the highest reaction rate constants (k1) was different depending on the acid catalysts. Among sulfuric, oxalic and maleic acid, the xylan reaction rate constants (k1) to xylose had the highest value of 0.0241 min-1 when 100 mM sulfuric acid was used at 120 .deg. C. However, sulfuric acid induced more xylose degradation compared to oxalic and maleic acid hydrolysis. The activation energy for xylan degradation was the highest when sulfuric acid was used

  13. Study on the Hydrolysis Kinetics of Xylan on Different Acid Catalysts

    Na, Byeong-Il; Lee, Jae-Won [Chonnam National University, Gwangju (Korea, Republic of)

    2014-04-15

    In this study, we investigated kinetic model for the acid-catalyzed xylan hydrolysis at temperature 120-150 .deg. C. Also, we analyzed the kinetic parameters for xylose production and furfural decomposition. The hydrolysis of xylan and the degradation of xylose were promoted by high reaction temperature and acid concentration. The optimal hydrolysis condition for the highest reaction rate constants (k{sub 1}) was different depending on the acid catalysts. Among sulfuric, oxalic and maleic acid, the xylan reaction rate constants (k{sub 1}) to xylose had the highest value of 0.0241 min{sup -1} when 100 mM sulfuric acid was used at 120 .deg. C. However, sulfuric acid induced more xylose degradation compared to oxalic and maleic acid hydrolysis. The activation energy for xylan degradation was the highest when sulfuric acid was used.

  14. Comparison of Enzymatic Hydrolysis and Acid Hydrolysis of Sterol Glycosides from Foods Rich in Δ(7)-Sterols.

    Münger, Linda H; Jutzi, Sabrina; Lampi, Anna-Maija; Nyström, Laura

    2015-08-01

    In this study, we present the difference in sterol composition of extracted steryl glycosides (SG) hydrolyzed by either enzymatic or acid hydrolysis. SG were analyzed from foods belonging to the plant families Cucurbitaceae (melon and pumpkin seeds) and Amaranthaceae (amaranth and beetroot), both of which are dominated by Δ(7)-sterols. Released sterols were quantified by gas chromatography with a flame ionization detector (GC-FID) and identified using gas chromatography/mass spectrometry (GC-MS). All Δ(7)-sterols identified (Δ(7)-stigmastenyl, spinasteryl, Δ(7)-campesteryl, Δ(7)-avenasteryl, poriferasta-7,25-dienyl and poriferasta-7,22,25-trienyl glucoside) underwent isomerization under acidic conditions and high temperature. Sterols with an ethylidene or methylidene side chain were found to form multiple artifacts. The artifact sterols coeluted with residues of incompletely isomerized Δ(7)-sterols, or Δ(5)-sterols if present, and could be identified as Δ(8(14))-sterols on the basis of relative retention time, and their MS spectra as trimethylsilyl (TMS) and acetate derivatives. For instance, SG from melon were composed of 66% Δ(7)-stigmastenol when enzymatic hydrolysis was performed, whereas with acid hydrolysis only 8% of Δ(7)-stigmastenol was determined. The artifact of Δ(7)-stigmastenol coeluted with residual non-isomerized spinasterol, demonstrating the high risk of misinterpretation of compositional data obtained after acid hydrolysis. Therefore, the accurate composition of SG from foods containing sterols with a double bond at C-7 can only be obtained by enzymatic hydrolysis or by direct analysis of the intact SG. PMID:25757602

  15. Acid hydrolysis of the biomass of resistant cellulose of thistle ''Onopordum nervosum boiss''

    Hydrolysis of resistant cellulose of ''Onopordum nervosum boiss'' (thistle) to reduce sugar in diluted sulfuric acid in glass ampoules and long residence times have been studied and kinetic parameters determined. The rate of hydrolysis is similar to that of the cellulose of Douglas fir, but comparatively the effect of the acid is more pronounced than temperature. From kinetic data the yield can be predicted and since it can be obtained at least 45% of the potential glucose (48% as reducing sugars) at 190 deg C, 1.6% acid and 6.1 min. residence time, it indicates that the continuous acid hydrolysis of thistle may be a process of commercial interest. (author)

  16. The influence of solid/liquid separation techniques on the sugar yield in two-step dilute acid hydrolysis of softwood followed by enzymatic hydrolysis

    Galbe Mats; Monavari Sanam; Zacchi Guido

    2009-01-01

    Abstract Background Two-step dilute acid hydrolysis of softwood, either as a stand-alone process or as pretreatment before enzymatic hydrolysis, is considered to result in higher sugar yields than one-step acid hydrolysis. However, this requires removal of the liquid between the two steps. In an industrial process, filtration and washing of the material between the two steps is difficult, as it should be performed at high pressure to reduce energy demand. Moreover, the application of pressure...

  17. Effect of an acid filler on hydrolysis and biodegradation of poly-lactic acid (PLA)

    Iozzino, Valentina; Speranza, Vito; Pantani, Roberto

    2015-12-01

    The use of biodegradable polymers is certainly an excellent strategy to solve many of the problems related to the disposal of the traditional polymers, whose accumulation in the environment is harmful and damaging. In order to optimize the use of biodegradable polymers, it is very important to understand and control the transformation processes, the structures and the morphologies resulting from the process conditions used to produce the articles and, not least, the biodegradation. The latter is strictly dependent on the just mentioned variables. The poly-lactic acid, PLA, is a biodegradable polymer. Many studies have been carried out on the degradation process of this polymer. In the course of this work we performed degradation tests on the PLA, with a specific D-isomer content, having amorphous structure, and in particular of biodegradation and hydrolysis. An acid chemical, fumaric acid, was added to PLA with the objective of controlling the rate of hydrolysis and of biodegradation. The hydrolysis process was followed, as function of time, by means of different techniques: pH variation, variation of weight of samples and variation of crystallinity degree and glass transition temperature using DSC analysis. The samples were also analyzed in terms of biodegradability by means of a homemade respirometer apparatus, in controlled composting conditions.

  18. Acid hydrolysis of cellulosic fibres: Comparison of bleached kraft pulp, dissolving pulps and cotton textile cellulose.

    Palme, Anna; Theliander, Hans; Brelid, Harald

    2016-01-20

    The behaviour of different cellulosic fibres during acid hydrolysis has been investigated and the levelling-off degree of polymerisation (LODP) has been determined. The study included a bleached kraft pulp (both never-dried and once-dried) and two dissolving pulps (once-dried). Additionally, cotton cellulose from new cotton sheets and sheets discarded after long-time use was studied. Experimental results from the investigation, together with results found in literature, imply that ultrastructural differences between different fibres affect their susceptibility towards acid hydrolysis. Drying of a bleached kraft pulp was found to enhance the rate of acid hydrolysis and also result in a decrease in LODP. This implies that the susceptibility of cellulosic fibres towards acid hydrolysis is affected by drying-induced stresses in the cellulose chains. In cotton cellulose, it was found that use and laundering gave a substantial loss in the degree of polymerisation (DP), but that the LODP was only marginally affected. PMID:26572472

  19. Comparison of dilute mineral and organic acid pretreatment for enzymatic hydrolysis of wheat straw

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

    2009-01-01

    The efficiencies of fumaric, maleic, and sulfuric acid in wheat straw pretreatment were compared. As a measure for pretreatment efficiency, enzymatic digestibility of the lignocellulose was determined. Monomeric glucose and xylose concentrations were measured after subsequent enzymatic hydrolysis, a

  20. Acid and enzymatic hydrolysis to recover reducing sugars from cassava bagasse: an economic study

    Woiciechowski Adenise Lorenci

    2002-01-01

    Full Text Available The objective of this work was to study the acid and enzymatic hydrolysis of cassava bagasse for the recovery of reducing sugars and to establish the operational costs. A statistical program "Statistica", based on the surface response was used to optimize the recovery of reducing sugars in both the processes. The process economics was determined considering the values of reducing sugars obtained at laboratory scale, and the operations costs of a cylindrical reactor of 1500 L, with flat walls at the top and bottom. The reactor was operated with 150 kg of cassava bagasse and 1350 kg of water. The yield of the acid hydrolysis was 62.4 g of reducing sugars from 100 g of cassava bagasse containing 66% starch. It represented 94.5% of reducing sugar recovery. The yield of the enzymatic hydrolysis was 77.1 g of reducing sugars from 120 g of cassava bagasse, which represented 97.3% of reducing sugars recovery. Concerning to the time, a batch of acid hydrolysis required 10 minutes, plus the time to heat and cool the reactor, and a batch of the enzymatic hydrolysis needed 25 hours and 20 minutes, plus the time to heat and to cool the reactor. Thus, the acid hydrolysis of 150 kg of cassava bagasse required US$ 34.27, and the enzymatic hydrolysis of the same amount of cassava bagasse required US$ 2470.99.

  1. Cellulase Inhibition by High Concentrations of Monosaccharides

    Hsieh, Chia-Wen; Cannella, David; Jørgensen, Henning;

    2014-01-01

    Biological degradation of biomass on an industrial scale culminates in high concentrations of end products. It is known that the accumulation of glucose and cellobiose, end products of hydrolysis, inhibit cellulases and decrease glucose yields. Aside from these end products, however, other...... that low free water availability contributes to cellulase inhibition. Of the hydrolytic enzymes involved, those acting on the cellulose substrate, that is, exo- and endoglucanases, were the most inhibited. The β -glucosidases were shown to be less sensitive to high monosaccharide concentrations except...

  2. Effect of pectins on the mass transfer kinetics of monosaccharides, amino acids, and a corn oil-in-water emulsion in a Franz diffusion cell.

    Espinal-Ruiz, Mauricio; Restrepo-Sánchez, Luz-Patricia; Narváez-Cuenca, Carlos-Eduardo

    2016-10-15

    The effect of high (HMP) and low (LMP) methoxylated pectins (2%w/w) on the rate and extent of the mass transfer of monosaccharides, amino acids, and a corn oil-in-water emulsion across a cellulose membrane was evaluated. A sigmoidal response kinetic analysis was used to calculate both the diffusion coefficients (rate) and the amount of nutrients transferred through the membrane (extent). In all cases, except for lysine, HMP was more effective than LMP in inhibiting both the rate and extent of the mass transfer of nutrients through the membrane. LMP and HMP, e.g., reduced 1.3 and 3.0times, respectively, the mass transfer rate of glucose, as compared to control (containing no pectin), and 1.3 and 1.5times, respectively, the amount of glucose transferred through the membrane. Viscosity, molecular interactions, and flocculation were the most important parameters controlling the mass transfer of electrically neutral nutrients, electrically charged nutrients, and emulsified lipids, respectively. PMID:27173546

  3. Optimization of dilute acid pretreatment of water hyacinth biomass for enzymatic hydrolysis and ethanol production.

    Idrees, Muhammad; Adnan, Ahmad; Sheikh, Shahzad; Qureshic, Fahim Ashraf

    2013-01-01

    The present study was conducted for the optimization of pretreatment process that was used for enzymatic hydrolysis of lignocellulosic biomass (Water Hyacinth, WH), which is a renewable resource for the production of bioethanol with decentralized availability. Response surface methodology has been employed for the optimization of temperature ((o)C), time (hr) and different concentrations of maleic acid (MA), sulfuric acid (SA) and phosphoric acid (PA) that seemed to be significant variables with P maleic acid > sulfuric acid. Mixture of sugars was obtained during dilute acid pretreatment with glucose being the most prominent sugar while pure glucose was obtained during enzymatic hydrolysis. The resulting sugars, obtained during enzymatic hydrolysis were finally fermented to ethanol, with yield 0.484 g/g of reducing sugars which is 95 % of theoretical yield (0.51 g/g glucose) by using commercial baker's yeast (Sacchromyces cerveasiae). PMID:26417215

  4. Solid Acid-Catalyzed Cellulose Hydrolysis Monitored by In Situ ATR-IR Spectroscopy

    Zakzeski, J.; Grisel, R.J.H.; Smit, A.T.; Weckhuysen, B.M.

    2012-01-01

    The solid acid-catalyzed hydrolysis of cellulose was studied under elevated temperatures and autogenous pressures using in situ ATR-IR spectroscopy. Standards of cellulose and pure reaction products, which include glucose, fructose, hydroxymethylfurfural (HMF), levulinic acid (LA), formic acid, and

  5. Enhanced xylose recovery from oil palm empty fruit bunch by efficient acid hydrolysis.

    Tan, Hooi Teng; Dykes, Gary A; Wu, Ta Yeong; Siow, Lee Fong

    2013-08-01

    Oil palm empty fruit bunch (EFB) is abundantly available in Malaysia and it is a potential source of xylose for the production of high-value added products. This study aimed to optimize the hydrolysis of EFB using dilute sulfuric acid (H2SO4) and phosphoric acid (H3PO4) via response surface methodology for maximum xylose recovery. Hydrolysis was carried out in an autoclave. An optimum xylose yield of 91.2 % was obtained at 116 °C using 2.0 % (v/v) H2SO4, a solid/liquid ratio of 1:5 and a hydrolysis time of 20 min. A lower optimum xylose yield of 24.0 % was observed for dilute H3PO4 hydrolysis at 116 °C using 2.4 % (v/v) H3PO4, a solid/liquid ratio of 1:5 and a hydrolysis time of 20 min. The optimized hydrolysis conditions suggested that EFB hydrolysis by H2SO4 resulted in a higher xylose yield at a lower acid concentration as compared to H3PO4. PMID:23709290

  6. Ultrasound-assisted dilute acid hydrolysis of tea processing waste for production of fermentable sugar.

    Germec, Mustafa; Tarhan, Kübra; Yatmaz, Ercan; Tetik, Nedim; Karhan, Mustafa; Demirci, Ali; Turhan, Irfan

    2016-03-01

    Lignocellulosic materials that are the most abundant plant biomass in the world have the potential to become sustainable sources of the produced value added products. Tea processing waste (TPW) is a good lignocellulosic source to produce the value added products from fermentable sugars (FSs). Therefore, the present study is undertaken to produce FSs by using ultrasound-assisted dilute acid (UADA) and dilute acid (DA) hydrolysis of TPW followed by enzymatic hydrolysis. UADA hydrolysis of TPW was optimized by response surface methodology (RSM) at maximum power (900 W) for 2 h. The optimum conditions were determined as 50°C, 1:6 (w/v) solid:liquid ratio, and 1% (w/v) DA concentration, which yielded 20.34 g/L FS concentration. Furthermore, its DA hydrolysis was also optimized by using RSM for comparison and the optimized conditions were found as 120°C, 1:8 solid:liquid ratio, and 1% acid concentration, which produced 25.3 g/L FS yield. Even though the produced sugars with UADA hydrolysis are slightly less, but it can provide significant cost saving due to the lower temperature requirement and less liquid consumption. Besides, enzymatic hydrolysis applied after pretreatments of TPW were very more economic than the conventional enzymatic hydrolysis in the literature due to shorter time requiring. In conclusion, ultrasound-assisted is a promising technology that can be successfully applied for hydrolysis of biomass and can be an alternative to the other hydrolysis procedures and also TPW can be considered as suitable carbon source for the production of value-added products like biofuels, organic acids, and polysaccharides. © 2016 American Institute of Chemical Engineers Biotechnol. Prog., 32:393-403, 2016. PMID:26749037

  7. [The current concepts on the absorption of monosaccharides, amino acids and peptides in the mammalian small intestine].

    Timofeeva, N M; Iezuitova, N N; Gromova, L V

    2000-01-01

    The review is mainly devoted to the development of ideas about absorption, or transport, of basic nutrients in the small intestine in humans and higher animal. The absorption processes have been characterized on the example of such substances, vital for organism, as carbohydrates and proteins. The review considers a molecular structure of transporters--protein molecules, which take part in a transfer of the products of lumenal and membrane digestion of carbohydrates (glucose, galactose, fructose) and proteins (amino acids, oligopeptides) across the enterocyte membranes. An information is presented about genetic disturbances of transport of certain amino acids during such diseases as Hartnup disease, cystinuria, and iminoglycineuria. PMID:11094795

  8. Optimization of acid hydrolysis from the hemicellulosic fraction of Eucalyptus grandis residue using response surface methodology.

    Canettieri, Eliana Vieira; de Moraes Rocha, George Jackson; de Carvalho, João Andrade; de Almeida e Silva, João Batista

    2007-01-01

    Biotechnological conversion of biomass into fuels and chemicals requires hydrolysis of the polysaccharide fraction into monomeric sugars. Hydrolysis can be performed enzymatically and with dilute or concentrate mineral acids. The present study used dilute sulfuric acid as a catalyst for hydrolysis of Eucalyptus grandis residue. The purpose of this paper was to optimize the hydrolysis process in a 1.4 l pilot-scale reactor and investigate the effects of the acid concentration, temperature and residue/acid solution ratio on the hemicellulose removal and consequently on the production of sugars (xylose, glucose and arabinose) as well as on the formation of by-products (furfural, 5-hydroxymethylfurfural and acetic acid). This study was based on a model composition corresponding to a 2(3) orthogonal factorial design and employed the response surface methodology (RSM) to optimize the hydrolysis conditions, aiming to attain maximum xylose extraction from hemicellulose of residue. The considered optimum conditions were: H(2)SO(4) concentration of 0.65%, temperature of 157 degrees C and residue/acid solution ratio of 1/8.6 with a reaction time of 20 min. Under these conditions, 79.6% of the total xylose was removed and the hydrolysate contained 1.65 g/l glucose, 13.65 g/l xylose, 1.55 g/l arabinose, 3.10 g/l acetic acid, 1.23 g/l furfural and 0.20 g/l 5-hydroxymethylfurfural. PMID:16473004

  9. Extraction of protein and amino acids from deoiled rice bran by subcritical water hydrolysis.

    Sereewatthanawut, Issara; Prapintip, Surawit; Watchiraruji, Katemanee; Goto, Motonobu; Sasaki, Mitsuru; Shotipruk, Artiwan

    2008-02-01

    This study investigated the production of value-added protein and amino acids from deoiled rice bran by hydrolysis in subcritical water (SW) in the temperature range between 100 and 220 degrees C for 0-30 min. The results suggested that SW could effectively be used to hydrolyze deoiled rice bran to produce useful protein and amino acids. The amount of protein and amino acids produced are higher than those obtained by conventional alkali hydrolysis. The yields generally increased with increased temperature and hydrolysis time. However, thermal degradation of the product was observed when hydrolysis was carried out at higher temperature for extended period of time. The highest yield of protein and amino acids were 219 +/- 26 and 8.0 +/- 1.6 mg/g of dry bran, and were obtained at 200 degrees C at hydrolysis time of 30 min. Moreover, the product obtained at 200 degrees C after 30 min of hydrolysis exhibited high antioxidant activity and was shown to be suitable for use as culture medium for yeast growth. PMID:17320384

  10. Hydrolysis of acid and alkali presoaked lignocellulosic biomass exposed to electron beam irradiation.

    Karthika, K; Arun, A B; Melo, J S; Mittal, K C; Kumar, Mukesh; Rekha, P D

    2013-02-01

    In this study, synergetic effect of mild acid and alkali with electron beam irradiation (EBI) on the enzymatic hydrolysis of a selected grass biomass was assessed. Biomass samples prepared by soaking with 1% H2SO4, or 1% NaOH, were exposed to 75 and 150 kGy of EBI. Water presoaked biomass was used as control. Hydrolysis of pretreated samples was carried out using cellulase (15 FPU/g biomass) for 120 h. Structural changes were studied by FTIR and XRD analyses. Reducing sugar and glucose yields from enzymatic hydrolysis were significantly higher in acid and alkali presoaked EBI exposed samples. Theoretical glucose yield showed 40% increase from control in alkali presoaked EBI exposed (150 kGy) samples. Removal of hemicellulose, decreased crystallinity and structural changes were major factors for the combined treatment effect favoring the hydrolysis. PMID:23298772

  11. Proto pectin degradation of raw material by the acid hydrolysis

    The article presents results of hydrolysis proto pectin apples, an orange and a basket of sunflower depending on ph a solution. The reaction products are divided into three fractions conditionally named as micro gel, pectin substances and oligosaccharide. It was shown that the high-quality pectin extracted from orange, but high percentage of carboxylic group in the sunflower pectin allow it to by used as a drug delivery materials

  12. Cellulose whiskers from sisal fibers: a study about the variable of extraction by acid hydrolysis

    The incorporation of cellulosic nanostructures in polymeric matrices has been studied due to their properties of biodegradation, and expected higher mechanical performance than the traditional composites. In this work, cellulose nanofibers were obtained from sisal bleached with reagents without chlorine, where it was used an acid mixture, with acetic acid and nitric acid, and after the bleached fibers were submitted to acid hydrolysis. The influence of the temperature and time of hydrolysis on the morphology and dimensions, crystallinity and thermal stability were analyzed by scanning transmission electronic microscopy (TEM), x-ray diffraction (XRD) and thermogravimetric analysis (TGA), respectively. The hydrolysis condition of 60 deg C and 15 minutes showed to be the most effective condition to obtain whiskers from sisal fibers, resulting in nanostructures with higher crystallinity and thermal. (author)

  13. Radiation pretreatments for optimizing the sugar yield in the acid hydrolysis of waste cellulose

    Cellulosic wastes are now recognized as an underutilized renewable resource for both materials and energy recovery rather than a solid waste disposal problem. Acid hydrolysis offers a potentially attractive route for upgrading the value of cellulosic wastes by converting them to glucose. The glucose can then be used as an alternate feedstock to petrochemicals for fuels, intermediates and the synthesis of single cell protein. A key step in this developing technology is a cost effective cellulose waste pretreatment for optimizing the sugar yield. Various experimental approaches for achieving this objective are described. A combination waste cellulose pretreatment comprising the hydropulping of an electron beam irradiated cellulose waste feedstock followed by a short time dilute sulfuric acid hydrolysis has been found to be particularly effective. Data are given on the employment of various organic acids in place of sulfuric acid for the hydrolysis reaction. The power requirement and additional cost for the electron beam pretreatment are also discussed. (Auth.)

  14. Comparative hydrolysis study of acetylsalicylic acid and copper - acetylsalicylate by rp-hplc method

    The hydrolysis of acetylsalicylic acid (ASA) and copper (II)-acetylsalicylate (CAS) was investigated by using a validated RP-HPLC method. Acetylsalicylic acid was hydrolyzed to (SA), where as CAS was hydrolyzed to ASA, SA, copper salicylate (CS), copper acetate and acetic acid. Comparison of hydrolysis was carried out by monitoring the concentration of SA, one of common hydrolysis product. The hydrolysis study was done in phosphate buffer solution in pH range from 3-11. The study was carried out at constant temperature to evaluate the effect of pH on both drugs. It was found that the hydrolysis rate of both drugs was same at pH value ranging from 3-11 as calculated from the Kapp and K values. However, there is a slight difference in the degradation of ASA and CAS as revealed from F-test. Results have indicated that CAS first hydrolyzes to acetylsalicylic acid which further hydrolyzes to SA, therefore availability of acetylsalicylic acid is increased. (author)

  15. Experimental and kinetic modelling studies on the acid-catalysed hydrolysis of the water hyacinth plant to levulinic acid

    Girisuta, B.; Danon, B.; Manurung, R.; Janssen, L. P. B. M.; Heeres, H. J.

    2008-01-01

    A comprehensive experimental and modelling study on the acid-catalysed hydrolysis of the water hyacinth plant (Eichhornia crassipes) to optimise the yield of levulinic acid (LA) is reported (T = 150-175 degrees C, C-H2SO4 - 0.1-1 M, water hyacinth intake = 1-5 wt%). At high acid concentrations (> 0.5 M), LA was the major organic acid whereas at low acid concentrations (

  16. Effect of Varying Acid Hydrolysis Condition in Gracilaria Sp. Fermentation Using Sasad

    Mansuit, H.; Samsuri, M. D. C.; Sipaut, C. S.; Yee, C. F.; Yasir, S. M.; Mansa, R.

    2015-04-01

    Macroalgae or seaweed is being considered as promising feedstock for bioalcohol production due to high polysaccharides content. Polysaccharides can be converted into fermentable sugar through acid hydrolysis pre-treatment. In this study, the potential of using carbohydrate-rich macroalgae, Gracilaria sp. as feedstock for bioalcohol production via various acid hydrolysis conditions prior to the fermentation process was investigated and evaluated. The seaweed used in this research was from the red algae group, using species of Gracilaria sp. which was collected from Sg. Petani Kedah, Malaysia. Pre-treatment of substrate was done using H2SO4 and HCl with molarity ranging from 0.2M to 0.8M. The pretreatment time were varied in the range of 15 to 30 minutes. Fermentation was conducted using Sasad, a local Sabahan fermentation agent as a starter culture. Alcohol extraction was done using a distillation unit. Reducing sugar analysis was done by Benedict test method. Alcohol content analysis was done using specific gravity test. After hydrolysis, it was found out that acid hydrolysis at 0.2M H2SO4 and pre-treated for 20 minutes at 121°C has shown the highest reducing sugar content which has yield (10.06 mg/g) of reducing sugar. It was followed by other samples hydrolysis using 0.4M HCl with 30 minutes pre-treatment and 0.2M H2SO4, 15 minutes pre-treatment with yield of 8.06 mg/g and 5.75 mg/g reducing sugar content respectively. In conclusion, acid hydrolysis of Gracilaria sp. can produce higher reducing sugar yield and thus it can further enhance the bioalcohol production yield. Hence, acid hydrolysis of Gracilaria sp. should be studied more as it is an important step in the bioalcohol production and upscaling process.

  17. The Optimum Conditions for Production of Soya Peptone by Acidic Hydrolysis of Soya Proteins

    Sundus H. Ahammed

    2009-01-01

    Full Text Available This study was carried out to obtain the optimum conditions necessary for the process of soya protein hydrolysis by using hydrochloric acid (as a chemical catalyst instead of the papain enzyme (as a biological catalyst, for the production of soya peptone. These conditions are implemented to test the effect of the variables of the process of hydrolysis on the nature and quality of the product. The production of soya peptone was studied for their importance in the process of preparing and producing the culture media used in medical and microbiological laboratories. The process of production of soya peptone includes four main stages:•Preparing the defatted soya flour, firstly.•The soya protein hydrolysis, secondly. •Purifying the product, thirdly , and then, •Drying the product, finally. By following the procedure of the present study, the optimum conditions for the process of soya proteins hydrolysis have been reached in present study are:•Optimum concentration for the hydrochloric acid solution is 1N.•Optimum hydrolysis process temperature ranged between 50-53C. •Optimum period of hydrolysis time ranged between 17.189-19.97 hr. The productivity of soya peptone was 38.071%, by following the procedure and the optimum production conditions of the present study.

  18. Factors affecting the rate of hydrolysis of phenylboronic acid in lab-scale precipitate reactor studies

    Removing aromatic carbon from an aqueous slurry of cesium-137 and other alkali tetraphenylborates by acid hydrolysis will be an important step in preparing high-level radioactive waste for vitrification at the Savannah River Site's Defense Waste Processing Facility (DWPF). Kinetic data obtained in bench-scale precipitate hydrolysis reactors suggest changes in operating parameters to improve product quality in the future plant-scale radioactive operation. The rate-determining step is the removal of the fourth phenyl group, i.e. hydrolysis of phenylboronic acid. Efforts to maximize this rate have established the importance of several factors in the system, including the ratio of copper(II) catalyst to formic acid, the presence of nitrite ion, reactions of diphenylmercury, and the purge gas employed in the system

  19. Factors affecting the rate of hydrolysis of phenylboronic acid in lab-scale precipitate reactor studies

    Bannochie, C.J.; Marek, J.C.; Eibling, R.E.; Baich, M.A.

    1992-10-01

    Removing aromatic carbon from an aqueous slurry of cesium-137 and other alkali tetraphenylborates by acid hydrolysis will be an important step in preparing high-level radioactive waste for vitrification at the Savannah River Site`s Defense Waste Processing Facility (DWPF). Kinetic data obtained in bench-scale precipitate hydrolysis reactors suggest changes in operating parameters to improve product quality in the future plant-scale radioactive operation. The rate-determining step is the removal of the fourth phenyl group, i.e. hydrolysis of phenylboronic acid. Efforts to maximize this rate have established the importance of several factors in the system, including the ratio of copper(II) catalyst to formic acid, the presence of nitrite ion, reactions of diphenylmercury, and the purge gas employed in the system.

  20. Factors affecting the rate of hydrolysis of phenylboronic acid in lab-scale precipitate reactor studies

    Bannochie, C.J.; Marek, J.C.; Eibling, R.E.; Baich, M.A.

    1992-01-01

    Removing aromatic carbon from an aqueous slurry of cesium-137 and other alkali tetraphenylborates by acid hydrolysis will be an important step in preparing high-level radioactive waste for vitrification at the Savannah River Site's Defense Waste Processing Facility (DWPF). Kinetic data obtained in bench-scale precipitate hydrolysis reactors suggest changes in operating parameters to improve product quality in the future plant-scale radioactive operation. The rate-determining step is the removal of the fourth phenyl group, i.e. hydrolysis of phenylboronic acid. Efforts to maximize this rate have established the importance of several factors in the system, including the ratio of copper(II) catalyst to formic acid, the presence of nitrite ion, reactions of diphenylmercury, and the purge gas employed in the system.

  1. Identification of Cultured and Natural Astragalus Root Based on Monosaccharide Mapping

    Ke Li

    2015-09-01

    Full Text Available As the main substances responsible for immunomodulatory activity, saccharides can be used as quality indicators for Astragalus root (RA. Saccharide content is commonly determined by ultraviolet spectroscopy, which lacks species specificity and has not been applied in the Chinese Pharmacopoeia. Monosaccharide mapping based on trifluoroacetic acid (TFA hydrolysis can be used for quantitative analysis of saccharide compositions. In addition, species specificity can be evaluated by analysis of the mapping characteristics. In this study, monosaccharide mapping of soluble saccharides in the cytoplasm and polysaccharides in the cell wall of 24 batches of RA samples with different growth patterns were obtained based on TFA hydrolysis followed by gas chromatography-mass spectrometry. Results indicated that the mapping and the molar ratios of saccharide compositions of the cultured and natural RA samples were different for both cytoplasm and cell wall. For example, the molar ratio of mannose and arabinose was more than 3.5:1 in cytoplasm in cultured RA, whereas the ratio was less than 3.5:1 in natural RA. This research not only lays a foundation for screening indicators for RA, but also provided new ways of evaluating the quality of Chinese medicinal materials in which saccharides are the main bioactive substances.

  2. Fatty acid specificity of hormone-sensitive lipase. Implication in the selective hydrolysis of triacylglycerols.

    Raclot, T; Holm, C; Langin, D

    2001-12-01

    The selective mobilization of fatty acids from white fat cells depends on their molecular structure, in particular the degree of unsaturation. The present study was designed to examine if the release of fatty acids by hormone-sensitive lipase (HSL) in vitro i) is influenced by the amount of unsaturation, ii) depends on the temperature, and iii) could explain the selective pattern of fatty acid mobilization and notably the preferential mobilization of certain highly unsaturated fatty acids. Recombinant rat and human HSL were incubated with a lipid emulsion. The hydrolysis of 35 individual fatty acids, ranging in chain length from 12 to 24 carbon atoms and in unsaturation from 0 to 6 double bonds was measured. Fatty acid composition of in vitro released NEFA was compared with that of fat cell triacylglycerols (TAG), the ratio % NEFA/% TAG being defined as the relative hydrolysis. The relative hydrolysis of individual fatty acids differed widely, ranging from 0.44 (24:1n-9) to 1.49 (18:1n-7) with rat HSL, and from 0.38 (24:1n-9) to 1.67 (18:1n-7) with human HSL. No major difference was observed between rat and human HSL. The relative release was dependent on the number of double bonds according to chain length. The amount of fatty acid released by recombinant rat HSL was decreased but remained robust at 4 degrees C compared with 37 degrees C, and the relative hydrolysis of some individual fatty acids was affected. The relative hydrolysis of fatty acids moderately, weakly, and highly mobilized by adipose tissue in vivo was similar and close to unity in vitro. We conclude that i) the release of fatty acids by HSL is only slightly affected by their degree of unsaturation, ii) the ability of HSL to efficiently and selectively release fatty acids at low temperature could reflect a cold adaptability for poikilotherms or hibernators when endogenous lipids are needed, and iii) the selectivity of fatty acid hydrolysis by HSL does not fully account for the selective pattern of

  3. Influence of acid precursors on physicochemical properties of nanosized titania synthesized by thermal-hydrolysis method

    The influence of nature and concentration of acid species on surface morphology and physicochemical properties of titania particles synthesized by direct thermal hydrolysis of titanium tetrachloride was investigated. The acids used were hydrochloric acid, nitric acid, sulfuric acid, and perchloric acid with a concentration of 3 M. Thermal hydrolysis of titanium tetrachloride in hydrochloric acid and perchloric acid with molar ratios of [H+]/[Ti4+] = 0.5, 1.0, 1.5, and 2.0, respectively, was used to study the effect of acid concentration. The synthesized materials were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, dynamic light scattering, and thermogravimetric analysis. Characterization of the samples by X-ray diffraction studies revealed the influence of acid species on the phase transformation of titania. Samples prepared by hydrochloric acid, nitric acid, and perchloric acid formed rutile phase with rhombus primary particles, while sulfuric acid resulted in anatase phase with flake-shaped primary particles. Transmission electron microscopy and dynamic light scattering results confirmed the nanosized titania particles and the agglomeration of primary particles to form secondary particles in spherical shape. The particle size of titania prepared using perchloric acid was smaller than those prepared with other acid sources. A direct correlation between [H+]/[Ti4+] ratio and particle size of titania was observed

  4. Humic Acid-Like and Fulvic Acid-Like Inhibition on the Hydrolysis of Cellulose and Tributyrin

    Fernandes, T.V.; Lier, van J.B.; Zeeman, Grietje

    2015-01-01

    Enzymatic hydrolysis of complex wastes is a critical step for efficient biogas production in anaerobic digesters. Inhibition of this hydrolytic step was studied by addition of humic acid-like (HAL) and fulvic acid-like (FAL) substances, extracted from maize silage and fresh cow manure, to batch t

  5. Optimization of dilute acid pretreatment of water hyacinth biomass for enzymatic hydrolysis and ethanol production

    Adnan, Ahmad; Idrees, Muhammad; Qureshi, Fahim Ashraf; Sheikh, Shahzad

    2013-01-01

    The present study was conducted for the optimization of pretreatment process that was used for enzymatic hydrolysis of lignocellulosic biomass (Water Hyacinth, WH), which is a renewable resource for the production of bioethanol with decentralized availability. Response surface methodology has been employed for the optimization of temperature (oC), time (hr) and different concentrations of maleic acid (MA), sulfuric acid (SA) and phosphoric acid (PA) that seemed to be significant variables wit...

  6. Production of reducing sugar from oil palm empty fruit bunch (EFB cellulose fibres via acid hydrolysis

    Siew Xian Chin

    2013-02-01

    Full Text Available Cellulosic fibre of oil palm empty fruit bunches (EFB were used as a raw material for acid hydrolysis using mineral acids (H2SO4 and HCl to produce reducing sugar at moderate temperature and atmospheric pressure. Experiments were carried out to investigate the effect of the hydrolysis parameters, including acid concentration, temperature, and reaction time, on the total reducing sugar (TRS yield with the aid of response surface methodology (RSM. The preliminary hydrolysis studies of the EFB fibres showed that the presence of lignin in the fibres significantly affected the TRS yield. The maximum predicted TRS yield using H2SO4 was 30.61% under optimal conditions: acid concentration of 5 N, temperature of 139.65 oC, and reaction time of 4.16 h. For the hydrolysis using HCl, the maximum predicted TRS yield is 39.81% under optimal conditions: acid concentration of 4.63 N, temperature of 133.7 oC, reaction time of 2.05 h.

  7. Hydrothermal upgrading of biomass to biofuel; studies on some monosaccharide model compounds.

    Srokol, Zbigniew; Bouche, Anne-Gaëlle; van Estrik, Anton; Strik, Rob C J; Maschmeyer, Thomas; Peters, Joop A

    2004-07-12

    During the hydrothermal upgrading of biomass, hydrolysis to glucose is an important step. To elucidate some of the reaction pathways that follow this initial hydrolysis, the hydrothermal treatment (340 degrees C, 27.5 MPa, 25-204 s) of dilute (50 mM) solutions of D-glucose and some other monosaccharides were studied. As a result of the increase of Kw under subcritical conditions, both acid and base catalysed reactions occur. The acid catalysed reactions are mainly dehydrations leading initially to 5-hydroxymethylfurfural. Important base catalysed reactions result in glycolaldehyde and glyceraldehyde. Further fragmentations and dehydrations lead to a variety of low molecular weight compounds such as formic acid, acetic acid, lactic acid, acrylic acid, 2-furaldehyde and 1,2,4-benzenetriol. Important pathways leading to a decrease of the O-content of the liquid reaction products start from the intermediate glyceraldehyde, which forms pyruvaldehyde, which in its turn is converted into formic acid and acetaldehyde. The latter compound can also be formed via isomerisation of glyceraldehyde into lactic acid followed by decarbonylation. PMID:15220081

  8. Acid hydrolysis of cellulose as the entry point into biorefinery schemes.

    Rinaldi, Roberto; Schüth, Ferdi

    2009-01-01

    Cellulose is a major source of glucose because it is readily available, renewable, and does not compete with the food supply. Hydrolysis of cellulose is experiencing a new research and development cycle in which this reaction is carried out over solid catalysts and coupled to other reactions for increased efficiency. Cellulose is typically not soluble in conventional solvents and very resistant to chemical and biological transformations. This Review focuses on aspects related to the hydrolysis of cellulose as this process is a significant entry point into the biorefinery scheme based on carbohydrates for the production of biofuels and biochemicals. Structural features of cellulose, conventional acid-catalyzed reactions, and the use of solid acid catalysts for hydrolysis are discussed. The longterm success of the biorefinery concept depends on the development of energetically efficient processes to convert cellulose directly or indirectly into biofuels and chemicals. PMID:19950346

  9. Preparation of Slowly Digestible Starch by Citric Acid-hydrolysis with Autoclaving

    Hansong Yu

    2015-03-01

    Full Text Available Aim of study is to produce Slowly Digestible Starch (SDS by a combination of citric acid-hydrolysis and autoclaving from raw corn starch. The effects of citric acid concentration, acid hydrolysis time, temperature and refrigeration and retro gradation time on the formation of SDS were investigated. The optimal process conditions optimized by Box-Benhnken’s central composite design and response surface analysis was as follows: concentration of citric acid is 0.08 M, acid hydrolyzed at 116°C for 14.5 min, and then stored at 0°C for 72 h. Under these optimal conditions, the content of SDS peaked at 19.38%.

  10. Monitoring the Hydrolysis of Olive Oil Catalyzed by Lipase via Acid Value Detection

    2007-01-01

    Hydrolysis of olive oil catalyzed by Candida lipolytica lipase was investigated. The relative concentration of the components in the product was determined by using high performance liquid chromatography(HPLC). Furthermore, a novel rapid method to detect the hydrolytic process of olive oil was developed based on the relationship between the acid value and the relative concentration of the different components.

  11. Catalytic conversion of carbohydrates to 5-hydroxymethylfurfural from the waste liquid of acid hydrolysis NCC.

    Sun, Yonghui; Liu, Pengtao; Liu, Zhong

    2016-05-20

    The principal goal of this work was to reuse the carbohydrates and recycle sulfuric acid in the waste liquid of acid hydrolysis nanocrystalline cellulose (NCC). Therefore, in this work, the optimizations of further hydrolysis of waste liquid of acid hydrolysis NCC and catalytic conversion of L4 to 5-hydroxymethylfurfural (5-HMF) were studied. Sulfuric acid was separated by spiral wound diffusion dialysis (SWDD). The results revealed that cellulose can be hydrolyze to glucose absolutely under the condition of temperature 35 °C, 3 h, and sulfuric acid's concentration 62 wt%. And 78.3% sulfuric acid was recovered by SWDD. The yield of 5-HMF was highest in aqueous solution under the optimal condition was as follows, temperature 160 °C, 3 h, and sulfuric acid's concentration 12 wt%. Then the effect of biphasic solvent systems catalytic conversion and inorganic salt as additives were still examined. The results showed that both of them contributed to prepare 5-HMF. The yield and selectivity of 5-HMF was up to 21.0% and 31.4%, respectively. PMID:26917388

  12. Changes of the Anthocyanins and Antioxidant properties of Concord Grape (Vitis labrusca Pomace After Acid Hydrolysis

    Mustafa Bener

    2016-05-01

    Full Text Available Grape pomace contains high levels of valuable antioxidants such as anthocyanins and phenolic compounds that help prevent chronic diseases such as cardiovascular problems and cancers. In this study, Concord grape pomace was soaked in acidic solutions at different time intervals and pHs in a water bath at 80 oC. Five kinds of anthocyanins were released and identified in the pomace after acid hydrolysis. The releasing rate of anthocyanins and antioxidant activities of the acid hydrolyzed pomace extracts were determined by multitest systems. Different antioxidant assays including total antioxidant capacity (TAC, total phenolic content (TPC and free radical scavenging activity (RSA were used to evaluate the antioxidant properties of the acid hydrolyzed pomace extracts. The change in antioxidant capacity of the pomace extracts during hydrolysis was correlated with total phenolic content and free radical scavenging activity but had little relationship with anthocyanin contents.

  13. Starch conversion of ganyong (Canna edulis Ker. to bioethanol using acid hydrolysis and fermentation

    LILY SURAYYA EKA PUTRI

    2008-04-01

    Full Text Available Starch of ganyong is one of the sources of ethanol which is able to be produced by acid hydrolysis and fermentation process. It had high concentration of carbohydrate that is 80%, so it could produce glucose highly within acid hydrolysis process. The result showed that the optimal amount of reducing sugar had been produced by nitrate acid 7% (dextrose equivalent, DE = 28.4. Nevertheless, type and concentration of acid had no significantly correlation to reducing sugar yielded. The total amount of glucose had correlation to amount of ethanol, in fermentation process. The optimal amount of ethanol was yielded from 4.81% of glucose and it produced about 4.84% ethanol. The more amount of glucose was yielded the more ethanol was produced. Controlling pH every 12 hours did not affected to production of ethanol significantly.

  14. Enzymatic hydrolysis and fermentation of dilute acid pretreated cornstalk to biohydrogen

    Pan, C. M.; Fan, Y. T.; Hou, H. W.

    2010-03-01

    The coupling method of acid pretreatment and enzymatic hydrolysis of cornstalk for hydrogen production was investigated in this study. Experimental results showed that temperature, pH and enzyme loading all had an individual significant influence on soluble sugar yield and Ps. The optimum condition for soluble sugar was close to that for Ps. The maximum hydrogen yield from cornstalk by anaerobic mixed microflora was 209.8 ml/g-TVS on the optimum enzymatic hydrolysis condition which was 52 °C of temperature, pH4.8 and 9.4 IU/g of enzyme loading.

  15. Xylitol from rice husks by acid hydrolysis and Candida yeast fermentation

    Magale K. D. Rambo; Daiane B. Bevilaqua; Carla G. B. Brenner; Ayrton F. Martins; Débora N. Mario; Sydney H. Alves; Carlos A. Mallmann

    2013-01-01

    An investigation was conducted into the production of xylose by acid hydrolysis of rice husks and its subsequent bioconversion to xylitol. The parameters were optimised using the response surface methodology. The fermentation stage took place with the aid of the yeast species Candida guilliermondii and Candida tropicalis. An evaluation of the influence of several biomass pre-treatments was also performed. The effects of the acid concentration and hydrolysate pH on xylitol global yield were al...

  16. Hydrolysis of Straw in Ionic Liquids with Acid as Catalyst under Microwave Irradiation

    Yuanjing Zhang; Gang Wei; Guangyi Yu; Ning Qiao

    2015-01-01

    With ionic liquids as solvents and corn straw as raw material, different processes of lignocellulose pretreatment with acid as catalyst were studied under conventional heating/microwave irradiation and the reducing sugar was measured. The results indicated that acid can accelerate hydrolysis reaction of corn straw into reducing sugar with ionic liquids as solvent, and microwave irradiation was more efficient in pretreatment of corn straw than conventional heating. The influences of different ...

  17. Hydrolysis optimization and characterization study of preparing fatty acids from Jatropha curcas seed oil

    Salimon Jumat; Abdullah Bashar; Salih Nadia

    2011-01-01

    Abstract Background Fatty acids (FAs) are important as raw materials for the biotechnology industry. Existing methods of FAs production are based on chemical methods. In this study potassium hydroxide (KOH)-catalyzed reactions were utilized to hydrolysis Jatropha curcas seed oil. Results The parameters effect of ethanolic KOH concentration, reaction temperature, and reaction time to free fatty acid (FFA%) were investigated using D-Optimal Design. Characterization of the product has been studi...

  18. Acid Pre hydrolysis of the Lignocellulose biomass from thistle Onopordum nervosum Boiss

    The acid pre hydrolysis of the lignocellulose biomass from thistle O. nervosum has been conducted to determine the conditions for maximum yield of pentoses with minimum yield of hexoses. Variables studied were acid concentration (H2SO4, 1 , 3, 4 and 5%) , temperature (1000 and 120 degree centigree) time, solid to liquid ratio and degree of fineness of thistle (1 to 65 mesh). (Author) 15 refs

  19. Acid Hydrolysis of Bromazepam Catalyzed by Micelles, Reverse Micelles, and Microemulsions

    Ferdousi Begum

    2015-01-01

    Full Text Available Kinetics of the acid hydrolysis of bromazepam (Bz has been investigated in micelles, reverse micelles, and microemulcions of cetyltrimethylammonium bromide (CTAB by spectrophotometric method. The rate of the acid hydrolysis of Bz was found to be enhanced both below and above the critical micelle concentration (CMC of CTAB in aqueous solution. The pseudo-first-order rate constant (k′ shows an initial decrease for both low and high H+ concentrations. With further increase in [CTAB], at low [H+], the k′ attains an almost constant value, while, at high [H+], the k′ passes through a maximum and then decreases. The kinetic data for catalysis by micelles of CTAB was interpreted with the pseudophase ion exchange (PIE model. In CTAB/cyclohexane/1-butanol/water microemulsions, as the water to surfactant ratio (wo increases, the physicochemical properties and droplet sizes of microemulsions significantly change and distinct changes in reaction environment can be marked. The rate of the hydrolysis reaction exhibits excellent correlation with the physicochemical properties and droplet sizes of the microemulsions and reverse micelles of CTAB. At [H+] = 0.001 M, in reverse micelles and microemulsions of CTAB, the k′ of the acid hydrolysis of Bz decreases sharply followed by a slight increase with increasing wo.

  20. Effect of gamma Irradiation on the acidic hydrolysis of free-hemi cellulose thistle

    The effect of gamma-irradiation on the subsequent acidic hydrolysis of free-hemi cellulose Onopordum Nervosum Boiss thistle Ls determined. Its shown the influence of gamma-irradiation on the yield of sugar obtained flora the batch wise hydrol isis of the call ulose (1% H2SO4 and 180 degree centigree at increasing doses. At all irradiation levels studied, the rate of hydrolysis of thistle samples was higher than the rate of hydrolysis of the cellulose from paper treated similarly. The maximum over-all yield of sugar in the irradiated lignocellulose material was about 66o at 100 MRad, less than two times the yield obtainable from the control. The corresponding yield from papel was 53%, 2'3 times that of the control. Irradiation under 1% H2SO4 doesn't enhance the yield anyway. (Author) 21 refs

  1. Production of agaro- and carra-oligosaccharides by partial acid hydrolysis of galactans

    Diogo R. B. Ducatti

    2011-04-01

    Full Text Available Agaro- and carra-oligosaccharides were produced by partial acid hydrolysis of commercial agarose and kappa-carrageenan. Di- and tetrasaccharides were purified by gel filtration chromatography and characterized by NMR (1D and 2D spectroscopy and ESIMS. The following oligosaccharides were obtained: agarobiose, agarotetraose, kappa-carrabiose and kappa-carratetraose. Agarobiose and agarotetraose were used as standards to develop a high performance size exclusion chromatography (HPSEC method which was utilized to study the hydrolysis rate of agarose and oligosaccharide production. Six hours of hydrolysis (0.1 M TFA, 65 ºC produced mainly di- and tetrasaccharides. The methodology for oligosaccharide production and evaluation developed in the present work shows good potential for the production of bioactive oligosaccharides.

  2. Production and effect of aldonic acids during enzymatic hydrolysis of lignocellulose at high dry matter content

    Cannella, David; Hsieh, Chia-Wen; Felby, Claus;

    2012-01-01

    Abstract Background: The recent discovery of accessory proteins that boost cellulose hydrolysis has increased the economical and technical efficiency of processing cellulose to bioethanol. Oxidative enzymes (e.g. GH61) present in new commercial enzyme preparations have shown to increase cellulose...... conversion yields. When using pure cellulose substrates it has been determined that both oxidized and unoxidized cellodextrin products are formed. We report the effect of oxidative activity in a commercial enzyme mix (Cellic CTec2) upon overall hydrolysis, formation of oxidized products and impact on ß...... hydrolysis of pretreated wheat straw at 30% WIS. Up to 4% of released glucose was oxidized into gluconic acid using Cellic CTec2, whereas no oxidized products were detected when using an earlier cellulase preparation Celluclast/Novozym188. However, the cellulose conversion yield was 25% lower using...

  3. Powerful peracetic acid-ionic liquid pretreatment process for the efficient chemical hydrolysis of lignocellulosic biomass.

    Uju; Goto, Masahiro; Kamiya, Noriho

    2016-08-01

    The aim of this work was to design a new method for the efficient saccharification of lignocellulosic biomass (LB) using a combination of peracetic acid (PAA) pretreatment with ionic liquid (IL)-HCl hydrolysis. The pretreatment of LBs with PAA disrupted the lignin fractions, enhanced the dissolution of LB and led to a significant increase in the initial rate of the IL-HCl hydrolysis. The pretreatment of Bagasse with PAA prior to its 1-buthyl-3-methylimidazolium chloride ([Bmim][Cl])-HCl hydrolysis, led to an improvement in the cellulose conversion from 20% to 70% in 1.5h. Interestingly, the 1-buthyl-3-methylpyridium chloride ([Bmpy][Cl])-HCl hydrolysis of Bagasse gave a cellulose conversion greater than 80%, with or without the PAA pretreatment. For LB derived from seaweed waste, the cellulose conversion reached 98% in 1h. The strong hydrolysis power of [Bmpy][Cl] was attributed to its ability to transform cellulose I to II, and lowering the degree of polymerization of cellulose. PMID:27174616

  4. The effect of acid hydrolysis pretreatment on crystallinity and solubility of kenaf cellulose membrane

    Cellulose was extracted from kenaf core pulp (KCP) by series of bleaching steps in the sequence (DEED) where D and E are referred as acid and alkali treatment. The bleached kenaf pulp (BKCP) is then pretreated with acid hydrolysis at room temperature for 1 and 3 h respectively. The pretreated cellulose is dissolved in lithium hydroxide/urea (LiOH/urea) and cellulose solution produced was immersed in distilled water bath. BKCP without treatment was also conducted for comparison purpose. The effects of acid hydrolysis pretreatment on solubility and crystallinity are investigated. Higher solubility of cellulose solution is achieved for treated samples. Cellulose II formation and crystallinity index of the cellulose membrane were determined by X-ray diffraction (XRD)

  5. The effect of acid hydrolysis pretreatment on crystallinity and solubility of kenaf cellulose membrane

    Saidi, Anis Syuhada Mohd; Zakaria, Sarani; Chia, Chin Hua; Jaafar, Sharifah Nabihah Syed; Padzil, Farah Nadia Mohammad [School of Applied Physics, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 UKM Bangi, Selangor (Malaysia)

    2015-09-25

    Cellulose was extracted from kenaf core pulp (KCP) by series of bleaching steps in the sequence (DEED) where D and E are referred as acid and alkali treatment. The bleached kenaf pulp (BKCP) is then pretreated with acid hydrolysis at room temperature for 1 and 3 h respectively. The pretreated cellulose is dissolved in lithium hydroxide/urea (LiOH/urea) and cellulose solution produced was immersed in distilled water bath. BKCP without treatment was also conducted for comparison purpose. The effects of acid hydrolysis pretreatment on solubility and crystallinity are investigated. Higher solubility of cellulose solution is achieved for treated samples. Cellulose II formation and crystallinity index of the cellulose membrane were determined by X-ray diffraction (XRD)

  6. The effect of acid hydrolysis pretreatment on crystallinity and solubility of kenaf cellulose membrane

    Saidi, Anis Syuhada Mohd; Zakaria, Sarani; Chia, Chin Hua; Jaafar, Sharifah Nabihah Syed; Padzil, Farah Nadia Mohammad

    2015-09-01

    Cellulose was extracted from kenaf core pulp (KCP) by series of bleaching steps in the sequence (DEED) where D and E are referred as acid and alkali treatment. The bleached kenaf pulp (BKCP) is then pretreated with acid hydrolysis at room temperature for 1 and 3 h respectively. The pretreated cellulose is dissolved in lithium hydroxide/urea (LiOH/urea) and cellulose solution produced was immersed in distilled water bath. BKCP without treatment was also conducted for comparison purpose. The effects of acid hydrolysis pretreatment on solubility and crystallinity are investigated. Higher solubility of cellulose solution is achieved for treated samples. Cellulose II formation and crystallinity index of the cellulose membrane were determined by X-ray diffraction (XRD).

  7. Optimization of wastewater microalgae saccharification using dilute acid hydrolysis for acetone, butanol, and ethanol fermentation

    Castro, Yessica; Ellis, Joshua T.; Miller, Charles D.; Sims, Ronald C.

    2015-02-01

    Exploring and developing sustainable and efficient technologies for biofuel production are crucial for averting global consequences associated with fuel shortages and climate change. Optimization of sugar liberation from wastewater algae through acid hydrolysis was determined for subsequent fermentation to acetone, butanol, and ethanol (ABE) by Clostridium saccharoperbutylacetonicum N1-4. Acid concentration, retention time, and temperature were evaluated to determine optimal hydrolysis conditions by assessing the sugar and ABE yield as well as the associated costs. Sulfuric acid concentrations ranging from 0-1.5 M, retention times of 40-120 min, and temperatures from 23°C- 90°C were combined to form a full factorial experiment. Acid hydrolysis pretreatment of 10% dried wastewater microalgae using 1.0 M sulfuric acid for 120 min at 80-90°C was found to be the optimal parameters, with a sugar yield of 166.1 g for kg of dry algae, concentrations of 5.23 g/L of total ABE, and 3.74 g/L of butanol at a rate of USD $12.83 per kg of butanol.

  8. Conformational Footprint in Hydrolysis-Induced Nanofibrillation and Crystallization of Poly(lactic acid).

    Xu, Huan; Yang, Xi; Xie, Lan; Hakkarainen, Minna

    2016-03-14

    The origin of hydrolysis-induced nanofibrillation and crystallization, at the molecular level, was revealed by mapping the conformational ordering during long-term hydrolytic degradation of initially amorphous poly(lactic acid) (PLA), a representative model for degradable aliphatic polyesters generally displaying strong interplay between crystallization and hydrolytic erosion. The conformational regularization of chain segments was essentially the main driving force for the morphological evolution of PLA during hydrolytic degradation. For hydrolysis at 37 °C, no significant structural variations were observed due to the immobilization of "frozen" PLA chains. In contrast, conformational ordering in PLA was immediately triggered during hydrolysis at 60 °C and was responsible for the transition from random coils to disordered trans and, further, to quasi-crystalline nanospheres. On the surfaces, the head-by-head absorption and joining of neighboring nanospheres led to nanofibrillar assemblies following a "gluttonous snake"-like manner. The length and density of nanofibers formed were in close relation to the hydrolytic evolution, both of which showed a direct rise in the initial 60 days and then a gradual decline. In the interior, presumably the high surface energy of the nanospheres allowed for the preferential anchoring and packing of conformationally ordered chains into lamellae. In accordance with the well-established hypothesis, the amorphous regions were attacked prior to the erosion of crystalline entities, causing a rapid increase of crystallinity during the initial 30 days, followed by a gradual fall until 90 days. In addition to adequate illustration of hydrolysis-induced variations of crystallinity, our proposed model elucidates the formation of spherulitic nuclei featuring an extremely wide distribution of diameters ranging from several nanometers to over 5 μm, as well as the inferior resistance to hydrolysis observed for the primary nuclei. Our work

  9. Facile, room-temperature pre-treatment of rice husks with tetrabutylphosphonium hydroxide: Enhanced enzymatic and acid hydrolysis yields.

    Lau, B B Y; Luis, E T; Hossain, M M; Hart, W E S; Cencia-Lay, B; Black, J J; To, T Q; Aldous, L

    2015-12-01

    Aqueous solutions of tetrabutylphosphonium hydroxide have been evaluated as pretreatment media for rice husks, prior to sulphuric acid hydrolysis or cellulase enzymatic hydrolysis. Varying the water:tetrabutylphosphonium hydroxide ratio varied the rate of delignification, as well as silica, lignin and cellulose solubility. Pre-treatment with 60wt% hydroxide dissolved the rice husk and the regenerated material was thus heavily disrupted. Sulphuric acid hydrolysis of 60wt%-treated samples yielded the highest amount of glucose per gram of rice husk. Solutions with good lignin and silica solubility but only moderate to negligible cellulose solubility (10-40wt% hydroxide) were equally effective as pre-treatment media for both acid and enzymatic hydrolysis. However, pre-treatment with 60wt% hydroxide solutions was incompatible with downstream enzymatic hydrolysis. This was due to significant incorporation of phosphonium species in the regenerated biomass, which significantly inhibited the activity of the cellulase enzymes. PMID:26342336

  10. Comparison of cell wall polysaccharide hydrolysis by a dilute acid/enzymatic saccharification process and rumen microorganisms

    Evaluation of biomass crops for breeding or pricing purposes requires an assay that predicts performance of biomass in the bioenergy conversion process. Cell wall polysaccharide hydrolysis by dilute sulfuric acid pretreatment at 121 degrees C followed by cellulase hydrolysis for 72 h (CONV) and in v...

  11. Synthesis of 18F-FDG using improved single-pot acid hydrolysis process

    In order to explore an optimum condition to increase the synthesis yield of 2-18F-2-deoxy-β-D-glucose (18F-FDG) by using improved single-pot acid hydrolysis Chemistry Process Control Unit (CPCU), various production conditions such as the reaction temperature, the time of acid hydrolysis and others were tested. The results showed that the determinant factor which affects the synthesis yield was the quantities of water present in reaction media. The total 18F-FDG synthesis time could be minimized by effective dehydration step and regulating the amount of hydrogen chloride. The synthesis yield could be increased by improving the production conditions of 18F-FDG. (authors)

  12. Nanocellulose prepared by acid hydrolysis of isolated cellulose from sugarcane bagasse

    Wulandari, W. T.; Rochliadi, A.; Arcana, I. M.

    2016-02-01

    Cellulose in nanometer range or called by nano-cellulose has attracted much attention from researchers because of its unique properties. Nanocellulose can be obtained by acid hydrolysis of cellulose. The cellulose used in this study was isolated from sugarcane bagasse, and then it was hydrolyzed by 50% sulfuric acid at 40 °C for 10 minutes. Nanocellulose has been characterized by Transmission Electron Microscope (TEM), Particle Size Analyzer (PSA), Fourier Transform Infrared Spectroscopy (FTIR) and X-Ray Diffraction (XRD). Analysis of FTIR showed that there were not a new bond which formed during the hydrolysis process. Based on the TEM analysis, nano-cellulose has a spherical morphology with an average diameter of 111 nm and a maximum distribution of 95.9 nm determined by PSA. The XRD analysis showed that the crystallinity degree of nano-cellulose was higher than cellulose in the amount of 76.01%.

  13. Concentrated Sulfuric Acid Hydrolysis of Hardwood Aspen and Softwood Pine for Bioethanol Production

    Janga, Kando Khalifa

    2011-01-01

    Bioethanol production from lignocellulosic biomass has been targeted as an alternative solution to the existing dependence on fossil fuels in the transportation sector. However, the recalcitrant nature of lignocelluloses has been a challenge to the hydrolytic processes and hence commercialization.This study has investigated the feasibility of the concentrated sulfuric acid hydrolysis (CSAH) process for bioethanol production from wood-based lignocelluloses. This is because the process enjoys h...

  14. Uniform particles formed by hydrolysis of acid mine drainage with urea

    Šubrt, Jan; Michalková, E.; Boháček, Jaroslav; Lukáč, Jozef; Gánovská, Z.; Máša, B.

    2011-01-01

    Roč. 106, 1-2 (2011), s. 12-18. ISSN 0304-386X R&D Projects: GA MŠk LC523; GA MŠk(CZ) MEB0810136 Institutional research plan: CEZ:AV0Z40320502 Keywords : acid mine drainage * urea hydrolysis * morphology * particles * surface area Subject RIV: CA - Inorganic Chemistry Impact factor: 2.027, year: 2011

  15. Acid and enzymatic hydrolysis to recover reducing sugars from cassava bagasse: an economic study

    Woiciechowski Adenise Lorenci; Nitsche Saul; Pandey Ashok; Soccol Carlos Ricardo

    2002-01-01

    The objective of this work was to study the acid and enzymatic hydrolysis of cassava bagasse for the recovery of reducing sugars and to establish the operational costs. A statistical program "Statistica", based on the surface response was used to optimize the recovery of reducing sugars in both the processes. The process economics was determined considering the values of reducing sugars obtained at laboratory scale, and the operations costs of a cylindrical reactor of 1500 L, with flat walls ...

  16. Conversion of cellulosic feedstocks to ethanol and other chemicals using TVA's dilute sulfuric acid hydrolysis process

    The Tennessee Valley Authority (TVA) has been involved in the conversion of cellulosic feedstocks to ethanol and other products for over 10 years. Laboratory- and bench-scale research has been conducted to develop a two-stage, dilute sulfuric acid hydrolysis process. The process, based on work previously conducted at the Forest Products Laboratory, Madison, Wisconsin, uses high temperatures and pressures and short retention times to convert the hemicellulose and cellulose in biomass to fermentable sugars. Using hardwoods as the primary feedstock, evaluations of the process have resulted in sugar yields equivalent to 60 gallons of ethanol per ton of feedstock. Based on the results of bench-scale work, a two-ton-per-day pilot plant has been constructed and operated to further develop the process. Hydrolysis yields from the pilot-scale facility have been comparable to those achieved in the laboratory. Preliminary estimates have been prepared to determine capital and production costs for a 10-million-gallon-per-year ethanol-from-hardwoods facility. The effect of coproducts such as furfural, acetic acid, and carbon dioxide on production costs was also examined. This paper presents the results of bench- and pilot-scale research along with preliminary economics of TVA's dilute sulfuric acid hydrolysis process

  17. Xylitol from rice husks by acid hydrolysis and Candida yeast fermentation

    Magale K. D. Rambo

    2013-01-01

    Full Text Available An investigation was conducted into the production of xylose by acid hydrolysis of rice husks and its subsequent bioconversion to xylitol. The parameters were optimised using the response surface methodology. The fermentation stage took place with the aid of the yeast species Candida guilliermondii and Candida tropicalis. An evaluation of the influence of several biomass pre-treatments was also performed. The effects of the acid concentration and hydrolysate pH on xylitol global yield were also assessed, and the highest yield of xylitol was 64.0% (w/w. The main products, xylose and xylitol, were identified and quantified by means of liquid chromatography.

  18. Determination of Amino Acids in Panax notoginseng by Microwave Hydrolysis and Derivatization Coupled with Capillary Zone Electrophoresis Detection

    LI Xiao-tian; ZHAO Ya-jing; JIANG Cheng-fei; ZHANG Han-qi; YU Ai-min

    2013-01-01

    The microwave hydrolysis and derivatization coupled with capillary electrophoresis detection were developed for the separation and determination of the amino acids in Panax notoginseng.The experimental conditions for the microwave hydrolysis and derivatization were examined and optimized.Several parameters of capillary electrophoresis,such as pH value of background electrolyte,borate concentration and applied voltage were optimized.Under the selected conditions,11 amino acids were completely separated.The real sample was analyzed and the results were satisfactory.Compared with that of conventional heat hydrolysis and derivatization,the analytical time of this method was significantly shortened.

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

    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.

  20. Sulfuric Acid Pretreatment and Enzymatic Hydrolysis of Photoperiod Sensitvie Sorghum for Ethanol Production

    F Xu; Y Shi; X Wu

    2011-12-31

    Photoperiod sensitive (PS) sorghum, with high soluble sugar content, high mass yield and high drought tolerance in dryland environments, has great potential for bioethanol production. The effect of diluted sulfuric acid pretreatment on enzymatic hydrolysis was investigated. Hydrolysis efficiency increased from 78.9 to 94.4% as the acid concentration increased from 0.5 to 1.5%. However, the highest total glucose yield (80.3%) occurred at the 1.0% acid condition because of the significant cellulose degradation at the 1.5% concentration. Synchrotron wide-angle X-ray diffraction was used to study changes of the degree of crystallinity. With comparison of cellulosic crystallinity and adjusted cellulosic crystallinity, the crystalline cellulose decreased after low acidic concentration (0.5%) applied, but did not change significantly, as the acid concentration increased. Scanning electron microscopy was also employed to understand how the morphological structure of PS sorghum changed after pretreatment. Under current processing conditions, the total ethanol yield is 74.5% (about 0.2 g ethanol from 1 g PS sorghum). A detail mass balance was also provided.

  1. Kinetic study of enzymatic hydrolysis of acid-pretreated coconut coir

    Fatmawati, Akbarningrum; Agustriyanto, Rudy

    2015-12-01

    Biomass waste utilization for biofuel production such as bioethanol, has become more prominent currently. Coconut coir is one of lignocellulosic food wastes, which is abundant in Indonesia. Bioethanol production from such materials consists of more than one step. Pretreatment and enzymatic hydrolysis is crucial steps to produce sugar which can then be fermented into bioethanol. In this research, ground coconut coir was pretreated using dilute sulfuric acid at 121°C. This pretreatment had increased the cellulose content and decreased the lignin content of coconut coir. The pretreated coconut coir was hydrolyzed using a mix of two commercial cellulase enzymes at pH of 4.8 and temperature of 50°C. The enzymatic hydrolysis was conducted at several initial coconut coir slurry concentrations (0.1-2 g/100 mL) and reaction times (2-72 hours). The reducing sugar concentration profiles had been produced and can be used to obtain reaction rates. The highest reducing sugar concentration obtained was 1,152.567 mg/L, which was produced at initial slurry concentration of 2 g/100 mL and 72 hours reaction time. In this paper, the reducing sugar concentrations were empirically modeled as a function of reaction time using power equations. Michaelis-Menten kinetic model for enzymatic hydrolysis reaction is adopted. The kinetic parameters of that model for sulfuric acid-pretreated coconut coir enzymatic hydrolysis had been obtained which are Vm of 3.587×104 mg/L.h, and KM of 130.6 mg/L.

  2. GC/MS determination of monosaccharides in yogurt products

    Yogurt products are known to be effective for enhancing health and preventing diseases such as cancers. Such effects are generally believed to be due to actions of polysaccharides in yogurt products. In this study we have determined compositions of monosaccharides in hydrolysates of commercial yogurt products as the first step of understanding structures of polysaccharides. The yogurt products were ultracentrifuged, filtered, hydrolyzed in 1M sulfuric acid and neutralized. A porting of the solution was taken and evaporated to dryness, derivatized with TMSI (trimethyl- silylimidazole) and analyzed by GC/MS. We found that the monosaccharides were fructose, glucose, and galactose. Their compositions were variant among several yogurt products

  3. A novel diffusion-biphasic hydrolysis coupled kinetic model for dilute sulfuric acid pretreatment of corn stover.

    Chen, Longjian; Zhang, Haiyan; Li, Junbao; Lu, Minsheng; Guo, Xiaomiao; Han, Lujia

    2015-02-01

    Kinetic experiments on the dilute sulfuric acid pretreatment of corn stover were performed. A high xylan removal and a low inhibitor concentration were achieved by acid pretreatment. A novel diffusion-hydrolysis coupled kinetic model was proposed. The contribution to the xylose yield was analyzed by the kinetic model. Compared with the inhibitor furfural negatively affecting xylose yield, the fast and slow-hydrolyzing xylan significantly contributed to the xylose yield, however, their dominant roles were dependent on reaction temperature and time. The impact of particle size and acid concentration on the xylose yield were also investigated. The diffusion process may significantly influence the hydrolysis of large particles. Increasing the acid concentration from 0.15 M to 0.30 M significantly improved the xylose yield, whereas the extent of improvement decreased to near-quantitative when further increasing acid loading. These findings shed some light on the mechanism for dilute sulfuric acid hydrolysis of corn stover. PMID:25479388

  4. Phosphine and thiophene cyclopalladated complexes: hydrolysis reactions in strong acidic media.

    García, Begoña; Hoyuelos, Francisco J; Ibeas, Saturnino; Muñoz, María S; Navarro, Ana M; Peñacoba, Indalecio A; Leal, José M

    2010-12-01

    The mechanisms for the hydrolysis of organopalladium complexes [Pd(CNN)R]BF(4) (R=P(OPh)(3), PPh(3), and SC(4)H(8)) were investigated at 25 °C by using UV/Vis absorbance measurements in 10 % v/v ethanol/water mixtures containing different sulphuric acid concentrations in the 1.3-11.7 M range. In all cases, a biphasic behavior was observed with rate constants k(1obs), which corresponds to the initial step of the hydrolysis reaction, and k(2obs), where k(1obs)>k(2obs). The plots of k(1obs) and k(2obs) versus sulfuric acid concentration suggest a change in the reaction mechanism. The change with respect to the k(1obs) value corresponds to 35 %, 2 %, and 99 % of the protonated complexes for R=PPh(3), P(OPh)(3), and SC(4)H(8), respectively. Regarding k(2obs), the change occurred in all cases at about 6.5 M H(2)SO(4) and matched up with the results reported for the hydrolysis of the 2-acetylpyridinephenylhydrazone (CNN) ligand. By using the excess acidity method, the mechanisms were elucidated by carefully looking at the variation of k(i),(obs) (i=1,2) versus cH+. The rate-determining constants, k(0,A-1), k(0,A-2), and k(0,A-SE2) were evaluated in all cases. The R=P(OPh)(3) complex was most reactive due to its π-acid character, which favors the rupture of the trans nitrogen-palladium bond in the A-2 mechanism and also that of the pyridine nitrogen-palladium bond in the A-1 mechanism. The organometallic bond exerts no effect on the relative basicity of the complexes, which are strongly reliant on the substituent. PMID:21125574

  5. Heteropoly Acid/Nitrogen Functionalized Onion-like Carbon Hybrid Catalyst for Ester Hydrolysis Reactions.

    Liu, Wei; Qi, Wei; Guo, Xiaoling; Su, Dangsheng

    2016-02-18

    A novel heteropoly acid (HPA)/nitrogen functionalized onion-like carbon (NOLC) hybrid catalyst was synthesized through supramolecular (electrostatic and hydrogen bond) interactions between the two components. The chemical structure and acid strength of the HPA/NOLC hybrid have been fully characterized by thermogravimetric analysis, IR spectroscopy, X-ray photoelectron spectroscopy, NH3 temperature-programmed desorption and acid-base titration measurements. The proposed method for the fabrication of the HPA/NOLC hybrid catalyst is a universal strategy for different types of HPAs to meet various requirements of acidic or redox catalysis. The hydrophobic environment of NOLC effectively prevents the deactivation of HPA in an aqueous system, and the combination of uniformly dispersed HPA clusters and the synergistic effect between NOLC and HPA significantly promotes its activity in ester hydrolysis reactions, which is higher than that of bare PWA as homogeneous catalyst. The kinetics of the hydrolysis reactions indicate that the aggregation status of the catalyst particles has great influence on the apparent activity. PMID:26606266

  6. Acid hydrolysis of sisal cellulose: studies aiming at nano fibers and bio ethanol preparation

    The hydrolysis of cellulose can result in nanofibers and also is an important stage in the bioethanol production process. In order to evaluate the influence of acid (sulfuric) concentration, temperature, and native cellulose (sisal) pretreatment on cellulose hydrolysis, the acid concentration was varied between 5% and 30% (v/v) in the temperature range from 60 to 100 deg C using native and alkali-treated (mercerized) sisal cellulose. The following techniques were used to evaluate the residual (non-hydrolysed) cellulose characteristics: viscometry, average degree of polymerization (DP), X-ray diffraction, crystallinity index, and Scanning Electron Microscopy. The sugar cane liquor was analyzed in terms of sugar composition, using High Performance Liquid Chromatography (HPLC). The results showed that increasing the concentration of sulfuric acid and temperature afforded residual cellulose with lower molecular weight and, up to specific acid concentrations, higher crystallinity indexes, when compared to the original cellulose values, and increased the glucose (the bioethanol precursor ) production of the liquor, which was favored for mercerized cellulose. (author)

  7. Acid-based hydrolysis processes for ethanol from lignocellulosic materials: A review

    Keikhosro Karimi

    2007-01-01

    Full Text Available Bioethanol is nowadays one of the main actors in the fuel market. It is currently produced from sugars and starchy materials, but lignocelluloses can be expected to be major feedstocks for ethanol production in the future. Two processes are being developed in parallel for conversion of lignocelluloses to ethanol, “acid-based” and “enzyme-based” processes. The current article is dedicated to review of progress in the “acid-based-hydrolysis” process. This process was used industrially in the 1940s, during wartime, but was not economically competitive afterward. However, intensive research and development on its technology during the last three decades, in addition to the expanding ethanol market, may revive the process in large scale once again. In this paper the ethanol market, the composition of lignocellulosic materials, concentrated- and dilute-acid pretreatment and hydrolysis, plug-flow, percolation, counter-current and shrinking-bed hydrolysis reactors, fermentation of hexoses and pentoses, effects of fermentation inhibitors, downstream processing, wastewater treatment, analytical methods used, and the current commercial status of the acid-based ethanol processes are reviewed.

  8. Effect of ultrasonic pre-treatment on low temperature acid hydrolysis of oil palm empty fruit bunch.

    Yunus, Robiah; Salleh, Shanti Faridah; Abdullah, Nurhafizah; Biak, Dyg Radiah Awg

    2010-12-01

    Various pre-treatment techniques change the physical and chemical structure of the lignocellulosic biomass and improve hydrolysis rates. The effect of ultrasonic pre-treatment on oil palm empty fruit bunch (OPEFB) fibre prior to acid hydrolysis has been evaluated. The main objective of this study was to determine if ultrasonic pre-treatment could function as a pre-treatment method for the acid hydrolysis of OPEFB fibre at a low temperature and pressure. Hydrolysis at a low temperature was studied using 2% sulphuric acid; 1:25 solid liquid ratio and 100 degrees C operating temperature. A maximum xylose yield of 58% was achieved when the OPEFB fibre was ultrasonicated at 90% amplitude for 45min. In the absence of ultrasonic pre-treatment only 22% of xylose was obtained. However, no substantial increase of xylose formation was observed for acid hydrolysis at higher temperatures of 120 and 140 degrees C on ultrasonicated OPEFB fibre. The samples were then analysed using a scanning electron microscope (SEM) to describe the morphological changes of the OPEFB fibre. The SEM observations show interesting morphological changes within the OPEFB fibre for different acid hydrolysis conditions. PMID:20719502

  9. Analysis of the monosaccharide composition of fucoidan by precolumn derivation HPLC

    ZHANG Jingjing; ZHANG Quanbin; WANG Jing; SHI Xuelian; ZHANG Zhongshan

    2009-01-01

    We developed an HPLC method for analysis of the monosaccharide composition of fucoidans. The fucoidan was hydrolyzed into monosaccharides with 2 mol/L trifluoroacetic acid. Using ribose as the internal standard, the monosaccharide derivatives, obtained with 1-Phenyl-3-methyl-5- pyrazolone (PMP), were separated by reverse-phase HPLC using a gradient elution process, and monitored by ultraviolet detection at 245 nm. In the concentration range of 0.1-2.0 mmol/L, the peak area of each monosaccharide had a good linear relationship with its concentration (r2>0.998). The average recoveries of mannose, rhamnose, glucuronic acid, glucose, galactose, xylose, and fucose were 86.2%, 95.1%, 62.5%, 102.0%, 94.8%, 66.6%, and 105.1%, respectively. This method was accurate and had good reproducibility and could be used to determine the monosaccharide contents of fucoidans.

  10. Analysis of the monosaccharide composition of fucoidan by precolumn derivation HPLC

    Zhang, Jingjing; Zhang, Quanbin; Wang, Jing; Shi, Xuelian; Zhang, Zhongshan

    2009-09-01

    We developed an HPLC method for analysis of the monosaccharide composition of fucoidans. The fucoidan was hydrolyzed into monosaccharides with 2 mol/L trifluoroacetic acid. Using ribose as the internal standard, the monosaccharide derivatives, obtained with 1-Phenyl-3-methyl-5-pyrazolone (PMP), were separated by reverse-phase HPLC using a gradient elution process, and monitored by ultraviolet detection at 245 nm. In the concentration range of 0.1-2.0 mmol/L, the peak area of each monosaccharide had a good linear relationship with its concentration ( r 2>0.998). The average recoveries of mannose, rhamnose, glucuronic acid, glucose, galactose, xylose, and fucose were 86.2%, 95.1%, 62.5%, 102.0%, 94.8%, 66.6%, and 105.1%, respectively. This method was accurate and had good reproducibility and could be used to determine the monosaccharide contents of fucoidans.

  11. Overall process considerations for using dilute acid cellulose hydrolysis technology to produce ethanol from biomass

    Recent advances in reactors, designed for the dilute acid thermochemical treatment of biomass, have resulted in the development of process alternatives in which both cellulose and hemicellulose are hydrolyzed to soluble sugars in high yields. The optimal extent of cellulose hydrolysis will depend on both the performance and economics of the thermochemical treatment operation, and on subsequent unit operations in the bioethanol production process. Examples of subsequent unit operation interactions include the extent to which cellulase enzymes are used to hydrolyze any remaining cellulose, kinetics and conditions of a largely soluble mixed sugar cofermentation, and the extent to which removal of compounds that inhabit fermenting microorganisms is required. In addition, a number of process operation and economic considerations affect the ultimate economic viability of this type of biomass hydrolysis process. These considerations include reactor design issues to accommodate the kinetic parameters of the various hydrolysis and sugar degradation reactions, liquid volume requirements to achieve acceptable sugar yields, sugar concentrations that result from such a process and their impact on subsequent fermentation volumes and ethanol recovery operations, potential co-product opportunities that result from solubilized lignin, and process steam requirements. Several potential whole-process configurations are presented and key process and economic issues for each are discussed. (author)

  12. Hydrolysis of Selected Tropical Plant Wastes Catalyzed by a Magnetic Carbonaceous Acid with Microwave

    Su, Tong-Chao; Fang, Zhen; Zhang, Fan; Luo, Jia; Li, Xing-Kang

    2015-12-01

    In this study, magnetic carbonaceous acids were synthesized by pyrolysis of the homogeneous mixtures of glucose and magnetic Fe3O4 nanoparticles, and subsequent sulfonation. The synthesis conditions were optimized to obtain a catalyst with both high acid density (0.75 mmol g-1) and strong magnetism [magnetic saturation, Ms = 19.5 Am2 kg-1]. The screened catalyst (C-SO3H/Fe3O4) was used to hydrolyze ball-milled cellulose in a microwave reactor with total reducing sugar (TRS) yield of 25.3% under the best conditions at 190 °C for 3.5 h. It was cycled for at least seven times with high catalyst recovery rate (92.8%), acid density (0.63 mmol g-1) and magnetism (Ms = 12.9 Am2 kg-1), as well as high TRS yield (20.1%) from the hydrolysis of ball-milled cellulose. The catalyst was further successfully tested for the hydrolysis of tropical biomass with high TRS and glucose yields of 79.8% and 58.3% for bagasse, 47.2% and 35.6% for Jatropha hulls, as well as 54.4% and 35.8% for Plukenetia hulls.

  13. Two New Dammarane Glycosides from the Acid Hydrolysis Product of Panax Notoginseng

    2001-01-01

    Two new dammarane glycosides named notoginsenoside T1 and T2 were isolated from the mild acid hydrolysis products of the root saponins of Panax notoginseng. On the basis of spectroscopic evidences, their structures were elucidated to be 6-O-?-D-glucopyranosyl-24(25)-epoxy-3?,6?,12?,23ξ-tetrahydroxydammar-20(22)(E)-ene 1 and 6-O-?-D-glucopyranosyl-24(25)-epoxy-23ξ-methoxyl-3?,6?,12?-trihydroxydamm-ar-20(22)(E)-ene 2, respectively.

  14. Nitrification of archaeal ammonia oxidizers in acid soils is supported by hydrolysis of urea

    Lu, Lu; Han, Wenyan; Zhang, Jinbo; Wu, Yucheng; Wang, Baozhan; Lin, Xiangui; Zhu, Jianguo; Cai, Zucong; Jia, Zhongjun

    2012-01-01

    The hydrolysis of urea as a source of ammonia has been proposed as a mechanism for the nitrification of ammonia-oxidizing bacteria (AOB) in acidic soil. The growth of Nitrososphaera viennensis on urea suggests that the ureolysis of ammonia-oxidizing archaea (AOA) might occur in natural environments. In this study, 15N isotope tracing indicates that ammonia oxidation occurred upon the addition of urea at a concentration similar to the in situ ammonium content of tea orchard soil (pH 3.75) and ...

  15. Isolation of pectin from pumpkin (Cucurbita moschata, L.) by acid hydrolysis

    Pumpkin (Cucurbita moschata, L.) constitutes an excellent source of carotenoids, precursors of vitamin A. Besides, it also that constitutes also a great natural source of low-cost pectin. Pectin is a heterogeneous complex polysaccharide found in the primary cell wall of most plants and its effect on health is receiving increasing interest from the scientific community. In this work, high-methoxy pectin was obtained from pumpkin (Cucurbita moschata, L.) through the acid hydrolysis methodology. The pectin obtained was characterized by FTIR, NMR 1H, GPC and rheology. (author)

  16. Catalytic hydrolysis of CFC-12 over solid acid Ti(SO4)2

    2000-01-01

    The catalytic hydrolysis of dichlorodifluoromethane (CFC-12) was investigated over solid acid Ti(SO4)2. The catalytic activity decreased with the calcination temperature. When space velocity was 6 l h-1 g-cat-1, the CFC-12 conversion at 310oC over Ti(SO4)2 calcined at 350oC remained about 98.5% during 360 h on stream, and the selectivity to by-products remained zero. The findings enlarged the scope of traditional catalyst systems for the CFCs decomposition.

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

    Jin Sun

    2010-11-01

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

  18. EFFECT OF INHIBITORS ON ENZYMATIC HYDROLYSIS AND SIMULTANEOUS SACCHARIFICATION FERMENTATION FOR LACTIC ACID PRODUCTION FROM STEAM EXPLOSION PRETREATED LESPEDEZA STALKS

    Yue Feng,

    2012-06-01

    Full Text Available The effects on both cellulose conversion rate and lactic acid yield were studied by adding inhibitors, including formic acid, acetic acid, furfural, and vanillin into the hydrolysate of steam-pretreated Lespedeza stalks. The results suggest that formic acid has a significant influence on the enzyme activity and poisoned bacterial cells, resulting in the reduction of cellulose conversion rate and lactic acid yield by 21% and 16.4%, respectively. Acetic acid showed a strong inhibition on simultaneous saccharification fermentation (SSF process, but little effect on enzymatic hydrolysis. Hydrolysis and SSF were less affected by furfural and vanillin compared with weak acids. The lactic acid yield of Lespedeza stalks rinsed with water increased from 64.0% to 89.4%, and the time to reach the maximum concentration was shortened from 96 hours to 48 hours when compared with the unwashed materials.

  19. Hydrolysis optimization and characterization study of preparing fatty acids from Jatropha curcas seed oil

    Salimon Jumat

    2011-11-01

    Full Text Available Abstract Background Fatty acids (FAs are important as raw materials for the biotechnology industry. Existing methods of FAs production are based on chemical methods. In this study potassium hydroxide (KOH-catalyzed reactions were utilized to hydrolysis Jatropha curcas seed oil. Results The parameters effect of ethanolic KOH concentration, reaction temperature, and reaction time to free fatty acid (FFA% were investigated using D-Optimal Design. Characterization of the product has been studied using Fourier transforms infrared spectroscopy (FTIR, gas chromatography (GC and high performance liquid chromatography (HPLC. The optimum conditions for maximum FFA% were achieved at 1.75M of ethanolic KOH concentration, 65°C of reaction temperature and 2.0 h of reaction time. Conclusions This study showed that ethanolic KOH concentration was significant variable for J. curcas seed oil hydrolysis. In a 18-point experimental design, FFA% of hydrolyzed J. curcas seed oil can be raised from 1.89% to 102.2%, which proved by FTIR and HPLC.

  20. Improvement Enzymatic Hydrolysis of Wheat Straw for Bioethanol Production by Combined Treatment of Radiation and Acid

    Hong, Sung Hyun; Lee, Seung Sik; Bai, Hyoung Woo; Chung, Byung Yeoup [Korea Atomic Energy Research Institute, Jeongeup (Korea, Republic of)

    2012-05-15

    The cost of ethanol production from starch and sucrose for use as a vehicle fuel is ultimately high. Consequently, it has been suggested that the large-scale use of ethanol as a fuel will require the utilization of cellulosic feedstock. Lignocellulosic biomass has the potential to serve as a low cost and renewable feedstock for bioconversion into fermentable sugars, which can be further utilized for biofuel production. It is estimated that there is over one billion tons of biomass available for conversion into biofuels on a renewable basis to displace a substantial portion of the fossil fuels currently consumed within the transportation sector. Among different pretreatment methods such as biological, physical, chemical, and physic-chemical pretreatments, chemical pretreatment using dilute acid as catalyst, which has been extensively evaluated for treating a variety of lignocellulosic feedstocks, is reported as one of the leading pretreatment technologies. Ionizing radiation can easily penetrate lignocellulosic structure and undoubtedly produce free radicals useful in modification of lignin structure as well as breakdown cellulose crystal regions. Phenoxy radicals appeared to be important radical intermediates that ultimately transformed into o-quinonoid structures in lignin. Therefore, ionizing radiation such as gamma ray and electron beam can be a great alternative. In this study, the effect of ionizing irradiation of wheat straw prior to dilute sulfuric acid treatment is investigated. The combined pretreatment for wheat straw was performed to evaluate the efficiency of enzymatic hydrolysis and compared with that of the effect of enzymatic hydrolysis by individual pretreatment

  1. Multiple-reaction monitoring liquid chromatography mass spectrometry for monosaccharide compositional analysis of glycoproteins.

    Hammad, Loubna A; Saleh, Marwa M; Novotny, Milos V; Mechref, Yehia

    2009-06-01

    A simple, sensitive, and rapid quantitative LC-MS/MS assay was designed for the simultaneous quantification of free and glycoprotein bound monosaccharides using a multiple reaction monitoring (MRM) approach. This study represents the first example of using LC-MS/MS methods to simultaneously quantify all common glycoprotein monosaccharides, including neutral and acidic monosaccharides. Sialic acids and reduced forms of neutral monosaccharides are efficiently separated using a porous graphitized carbon column. Neutral monosaccharide molecules are detected as their alditol acetate anion adducts [M + CH(3)CO(2)](-) using electrospray ionization in negative ion MRM mode, while sialic acids are detected as deprotonated ions [M - H](-). The new method exhibits very high sensitivity to carbohydrates with limits of detection as low as 1 pg for glucose, galactose, and mannose, and below 10 pg for other monosaccharides. The linearity of the described approach spans over three orders of magnitudes (pg to ng). The method effectively quantified monosaccharides originating from as little as 1 microg of fetuin, ribonuclease B, peroxidase, and alpha(1)-acid glycoprotein human (AGP) with results consistent with literature values and with independent CE-LIF measurements. The method is robust, rapid, and highly sensitive. It does not require derivatization or postcolumn addition of reagents. PMID:19318280

  2. Hydrolysis of Miscanthus for bioethanol production using dilute acid presoaking combined with wet explosion pre-treatment and enzymatic treatment

    Sørensen, Annette; Teller, Philip Johan; Hilstrøm, Troels;

    2008-01-01

    Miscanthus is a high yielding bioenergy crop. In this study we used acid presoaking, wet explosion, and enzymatic hydrolysis to evaluate the combination of the different pre-treatment methods for bioethanol production with Miscanthus. Acid presoaking is primarily carried out in order to remove...

  3. Effect of acid hydrolysis and fungal biotreatment on agro-industrial wastes for obtainment of free sugars for bioethanol production

    T.S. El-Tayeb

    2012-12-01

    Full Text Available This study was designed to evaluate selected chemical and microbiological treatments for the conversion of certain local agro-industrial wastes (rice straw, corn stalks, sawdust, sugar beet waste and sugarcane bagasse to ethanol. The chemical composition of these feedstocks was determined. Conversion of wastes to free sugars by acid hydrolysis varied from one treatment to another. In single-stage dilute acid hydrolysis, increasing acid concentration from 1 % (v/v to 5 % (v/v decreased the conversion percentage of almost all treated agro-industrial wastes. Lower conversion percentages for some treatments were obtained when increasing the residence time from 90 to 120min. The two-stage dilute acid hydrolysis by phosphoric acid (1.0 % v/v followed by sulphuric acid (1.0 % v/v resulted in the highest conversion percentage (41.3 % w/w on treated sugar beet waste. This treatment when neutralized, amended with some nutrients and inoculated with baker's yeast, achieved the highest ethanol concentration (1.0 % v/v. Formation of furfural and hydroxymethylfurfural (HMF were functions of type of acid hydrolysis, acid concentration, residence time and feedstock type. The highest bioconversion of 5 % wastes (37.8 % w/w was recorded on sugar beet waste by Trichoderma viride EMCC 107. This treatment when followed by baker's yeast fermentation, 0.41 % (v/v ethanol and 8.2 % (v/w conversion coefficient were obtained.

  4. Accelerated hydrolysis method to estimate the amino acid content of wheat (Triticum durum Desf.) flour using microwave irradiation.

    Kabaha, Khaled; Taralp, Alpay; Cakmak, Ismail; Ozturk, Levent

    2011-04-13

    The technique of microwave-assisted acid hydrolysis was applied to wholegrain wheat (Triticum durum Desf. cv. Balcali 2000) flour in order to speed the preparation of samples for analysis. The resultant hydrolysates were chromatographed and quantified in an automated amino acid analyzer. The effect of different hydrolysis temperatures, times and sample weights was examined using flour dispersed in 6 N HCl. Within the range of values tested, the highest amino acid recoveries were generally obtained by setting the hydrolysis parameters to 150 °C, 3 h and 200 mg sample weight. These conditions struck an optimal balance between liberating amino acid residues from the wheat matrix and limiting their subsequent degradation or transformation. Compared to the traditional 24 h reflux method, the hydrolysates were prepared in dramatically less time, yet afforded comparable ninhydrin color yields. Under optimal hydrolysis conditions, the total amino acid recovery corresponded to at least 85.1% of the total protein content, indicating the efficient extraction of amino acids from the flour matrix. The findings suggest that this microwave-assisted method can be used to rapidly profile the amino acids of numerous wheat grain samples, and can be extended to the grain analysis of other cereal crops. PMID:21375298

  5. Adsorption and hydrolysis of isocyanic acid on TiO2

    The interaction of isocyanic acid (HNCO) with titania in the anatase modification has been investigated by means of DRIFT spectroscopy and TPD experiments. HNCO adsorbs dissociatively on TiO2 to yield isocyanate (NCO) groups, bound to Ti4+ sites, and hydroxyl (OH) groups. The stability of these NCO groups decreases with increasing temperatures, and at T>200oC they are very easily removed from the surface. In the presence of water, the hydrolysis of the NCO species to ammonia is also fostered by elevating the temperature. Moreover, HNCO adsorption on a sample previously exposed to ammonia revealed that competitive adsorption occurs on the surface. The catalytic activity of TiO2 for the hydrolyis of HNCO was investigated in a micro plug-flow reactor and correlated with the stability and reactivity of the isocyanate species found by DRIFT spectroscopy. The results are discussed in view of the role of the HNCO hydrolysis in the selective catalytic reduction (SCR) of diesel NOx emissions with urea (urea-SCR process). (author)

  6. Strategies to achieve high-solids enzymatic hydrolysis of dilute-acid pretreated corn stover.

    Geng, Wenhui; Jin, Yongcan; Jameel, Hasan; Park, Sunkyu

    2015-01-01

    Three strategies were presented to achieve high solids loading while maximizing carbohydrate conversion, which are fed-batch, splitting/thickening, and clarifier processes. Enzymatic hydrolysis was performed at water insoluble solids (WIS) of 15% using washed dilute-acid pretreated corn stover. The carbohydrate concentration increased from 31.8 to 99.3g/L when the insoluble solids content increased from 5% to 15% WIS, while the final carbohydrate conversion was decreased from 78.4% to 73.2%. For the fed-batch process, a carbohydrate conversion efficiency of 76.8% was achieved when solid was split into 60:20:20 ratio, with all enzymes added first. For the splitting/thickening process, a carbohydrate conversion of 76.5% was realized when the filtrate was recycled to simulate a steady-state process. Lastly, the clarifier process was evaluated and the highest carbohydrate conversion of 81.4% was achieved. All of these results suggests the possibility of enzymatic hydrolysis at high solids to make the overall conversion cost-competitive. PMID:25836373

  7. Methane production from acid hydrolysates of Agave tequilana bagasse: evaluation of hydrolysis conditions and methane yield.

    Arreola-Vargas, Jorge; Ojeda-Castillo, Valeria; Snell-Castro, Raúl; Corona-González, Rosa Isela; Alatriste-Mondragón, Felipe; Méndez-Acosta, Hugo O

    2015-04-01

    Evaluation of diluted acid hydrolysis for sugar extraction from cooked and uncooked Agave tequilana bagasse and feasibility of using the hydrolysates as substrate for methane production, with and without nutrient addition, in anaerobic sequencing batch reactors (AnSBR) were studied. Results showed that the hydrolysis over the cooked bagasse was more effective for sugar extraction at the studied conditions. Total sugars concentration in the cooked and uncooked bagasse hydrolysates were 27.9 g/L and 18.7 g/L, respectively. However, 5-hydroxymethylfurfural was detected in the cooked bagasse hydrolysate, and therefore, the uncooked bagasse hydrolysate was selected as substrate for methane production. Interestingly, results showed that the AnSBR operated without nutrient addition obtained a constant methane production (0.26 L CH4/g COD), whereas the AnSBR operated with nutrient addition presented a gradual methane suppression. Molecular analyses suggested that methane suppression in the experiment with nutrient addition was due to a negative effect over the archaeal/bacterial ratio. PMID:25647030

  8. The shape and size distribution of crystalline nanoparticles prepared by acid hydrolysis of native cellulose.

    Elazzouzi-Hafraoui, Samira; Nishiyama, Yoshiharu; Putaux, Jean-Luc; Heux, Laurent; Dubreuil, Frédéric; Rochas, Cyrille

    2008-01-01

    The shape and size distribution of crystalline nanoparticles resulting from the sulfuric acid hydrolysis of cellulose from cotton, Avicel, and tunicate were investigated using transmission electron microscopy (TEM) and atomic force microscopy (AFM) as well as small- and wide-angle X-ray scattering (SAXS and WAXS). Images of negatively stained and cryo-TEM specimens showed that the majority of cellulose particles were flat objects constituted by elementary crystallites whose lateral adhesion was resistant against hydrolysis and sonication treatments. Moreover, tunicin whiskers were described as twisted ribbons with an estimated pitch of 2.4-3.2 microm. Length and width distributions of all samples were generally well described by log-normal functions, with the exception of tunicin, which had less lateral aggregation. AFM observation confirmed that the thickness of the nanocrystals was almost constant for a given origin and corresponded to the crystallite size measured from peak broadening in WAXS spectra. Experimental SAXS profiles were numerically simulated, combining the dimensions and size distribution functions determined by the various techniques. PMID:18052127

  9. Enantioselective Hydrolysis of Amino Acid Esters Promoted by Bis(β-cyclodextrin) Copper Complexes

    Xue, Shan-Shan; Zhao, Meng; Ke, Zhuo-Feng; Cheng, Bei-Chen; Su, Hua; Cao, Qian; Cao, Zhen-Kun; Wang, Jun; Ji, Liang-Nian; Mao, Zong-Wan

    2016-02-01

    It is challenging to create artificial catalysts that approach enzymes with regard to catalytic efficiency and selectivity. The enantioselective catalysis ranks the privileged characteristic of enzymatic transformations. Here, we report two pyridine-linked bis(β-cyclodextrin) (bisCD) copper(II) complexes that enantioselectively hydrolyse chiral esters. Hydrolytic kinetic resolution of three pairs of amino acid ester enantiomers (S1-S3) at neutral pH indicated that the “back-to-back” bisCD complex CuL1 favoured higher catalytic efficiency and more pronounced enantioselectivity than the “face-to-face” complex CuL2. The best enantioselectivity was observed for N-Boc-phenylalanine 4-nitrophenyl ester (S2) enantiomers promoted by CuL1, which exhibited an enantiomer selectivity of 15.7. We observed preferential hydrolysis of L-S2 by CuL1, even in racemic S2, through chiral high-performance liquid chromatography (HPLC). We demonstrated that the enantioselective hydrolysis was related to the cooperative roles of the intramolecular flanking chiral CD cavities with the coordinated copper ion, according to the results of electrospray ionization mass spectrometry (ESI-MS), inhibition experiments, rotating-frame nuclear Overhauser effect spectroscopy (ROESY), and theoretical calculations. Although the catalytic parameters lag behind the level of enzymatic transformation, this study confirms the cooperative effect of the first and second coordination spheres of artificial catalysts in enantioselectivity and provides hints that may guide future explorations of enzyme mimics.

  10. Bioethanol Production from Coconut Fiber Using Alkaline Pretreatment and Acid Hydrolysis Method

    Asyeni Miftahul Jannah

    2015-01-01

    Full Text Available Supporting Indonesia government program to decrease fuel consumption, using renewable energy such of bioethanol is one of the best ways. This research was done in order to utilize agriculture waste (coconut fiber as raw material to produce bioetanol. However, coconut fiber contents lignin that will inhibit conversion process of glucose into ethanol. In this research, pretreatment steps aim to release and breakdown lignin in coconut fiber. Pretreatment was conducted by using alkaline method with 3% Sodium Hydroxide solution. Hydrolysis method was used to produce glucose by using Sulfuric Acid solution with various concentrations (1%, 2%, 3%, and 4 % while in fermentation process used Saccharomyces cerevisiae with various times (5, 7, 9, and 11 days and distillation used to get pure product of bioethanol. The results showed that higher H2SO4 concentration using on hydrolysis process made more glucose converted to bioethanol. The highest bioethanol content produced was 5.9420% from sample of 4% H2SO4 in 7 days of fermentation.

  11. DETERMINATION OF AMINO ACIDS IN TWO POLYSIPHONIA SPECIES AND STUDY OF ENZYMATIC HYDROLYSIS METHOD

    张立新; 范晓; 魏玉西

    2002-01-01

    The total content of the rich amino acids in two common red algae, Polysiphoni a urceolata and Polysiphonia japonica growing in the Qingdao seashore were d etermi ned. The algae powder was hydrolyzed by 6 mol/L HCl at 110℃ for 48 h and determ ined by amino acid analyzer. The content was 25.35% and 24.16%, respectively, mu ch higher than that of some other species. In addition, a nutritive liquid with abundant amino acids was prepared (by the enzymatic hydrolysis method using Po lys iphonia urceolata) as raw material for a kind of health beverage. The dried se aweed was decolored by 0.25% KMnO4 and 0.5% active carbon, then enzymalized. In the selection of enzymalizing condition, the orthogonal experimental design w as used. Four factors including kinds of enzyme, quantity of enzyme, temperature and time were studied at 3 leve ls. According to the orthogonal design results, we can choose an optimal condition: hydrolyzing at 45℃ by neutr al proteinase (0.25%, w/w) for 2 h, adjusting pH to 8.5, then adding trypsin (0.25%, w/w) and hydrolyzing for 2 h. F inally the above solution was alkalized by NaOH and neutralized by casein. After the hydrolyzed liquid was fil tered and concentrated, suitable additives were added. The final products contain rich amino acids.

  12. DETERMINATION OF AMINO ACIDS IN TWO POLYSIPHONIA SPECIES AND STUDY OF ENZYMATIC HYDROLYSIS METHOD

    张立新; 范晓; 魏玉西

    2002-01-01

    The total content ot the nch amino acids in two common red algae, Potystpnoma urceolata and Polysiphonia japonica growing in the Qingdao seashore were determined. The algae powder was hydrolyzed by 6 mol/L HC1 at 110℃ for 48 h and determined by amino acid analyzer. The content was 25.35% and 24.16% , respectively, much higher than that of some other species. In addition, a nutritive liquid with abundant amino acids was prepared (by the enzymatic hydrolysis method using Polysiphonia urceolata ) as raw material for a kind of health beverage. The dried seaweed was decolored by 0.25% KMnO4 and 0.5% active carbon, then enzymalized. In the selection of enzymalizing condition, the orthogonal experimental design was used. Four factors including kinds of enzyme, quantity of enzyme, temperature and time were studied at 3 levels. According to the orthogonal design results, we can choose an optimal condition: hydrolyzing at 45℃ by neutral proteinase (0.25% , w/w) for 2 h, adjusting pH to 8.5, then adding trypsin (0.25% , w/w) and hydrolyzing for 2 h. Finally the above solution was alkalized by NaOH and neutralized by casein. After the hydrolyzed liquid was filtered and concentrated, suitable additives were added. The final products contain rich amino acids.

  13. Determination of amino acids in two Polysiphonia species and study of enzymatic hydrolysis method

    Zhang, Li-Xin; Fan, Xiao; Wei, Yu-Xi

    2002-09-01

    The total content of the rich amino acids in two common red algae, Polysiphonia urceolata and Polysiphonia japonica growing in the Qingdao seashore were determined. The algae powder was hydrolyzed by 6 mol/L HCl at 110°C for 48 h and determined by amino acid analyzer. The content was 25.35% and 24.16%, respectively, much higher than that of some other species. In addition, a nutritive liquid with abundant amino acids was prepared (by the enzymatic hydrolysis method using Polysiphonia urceolata) as raw material for a kind of health beverage. The dried seaweed was decolored by 0.25% KMnO4 and 0.5% active carbon, then enzymalized. In the selection of enzymalizing condition, the orthogonal experimental design was used. Four factors including kinds of enzyme, quantity of enzyme, temperature and time were studied at 3 levels. According to the orthogonal design results, we can choose an optimal condition: hydrolyzing at 45°C by neutral proteinase (0.25%, w/w) for 2h, adjusting pH to 8.5, then adding trypsin (0.25%, w/w) and hydrolyzing for 2 h. Finally the above solution was alkalized by NaOH and neutralized by casein. After the hydrolyzed liquid was filtered and concentrated, suitable additives were added. The final products contain rich amino acids.

  14. Cellulose nanocrystals prepared via formic acid hydrolysis followed by TEMPO-mediated oxidation.

    Li, Bin; Xu, Wenyang; Kronlund, Dennis; Määttänen, Anni; Liu, Jun; Smått, Jan-Henrik; Peltonen, Jouko; Willför, Stefan; Mu, Xindong; Xu, Chunlin

    2015-11-20

    Cellulose nanocrystals (CNCs) as a renewable and biodegradable nanomaterial have wide application value. In this work, CNCs were extracted from bleached chemical pulp using two stages of isolation (i.e. formic acid (FA) hydrolysis and 2,2,6,6-tetramethyl-piperidine-1-oxyl (TEMPO) mediated oxidation) under mild conditions. In the first stage, FA was used to remove hemicellulose, swell cellulose fibers, and release CNCs. The FA could be readily recovered and reused. In the second stage, the CNCs isolated by FA were further modified by TEMPO-mediated oxidation to increase the surface charge of CNCs. It was found that the modified CNCs with more ordered crystal structure and higher surface charge had better redispersibility and higher viscosity in aqueous phase. Therefore, the modified CNCs could be more effective when used as rheology modifier in the fields of water based coating, paint, food etc. PMID:26344319

  15. Bioreversible Derivatives of Phenol. 2. Reactivity of Carbonate Esters with Fatty Acid-like Structures Towards Hydrolysis in Aqueous Solutions

    Claus Larsen

    2007-10-01

    Full Text Available A series of model phenol carbonate ester prodrugs encompassing derivatives with fatty acid-like structures were synthesized and their stability as a function of pH (range 0.4 – 12.5 at 37°C in aqueous buffer solutions investigated. The hydrolysis rates in aqueous solutions differed widely, depending on the selected pro-moieties (alkyl and aryl substituents. The observed reactivity differences could be rationalized by the inductive and steric properties of the substituent groups when taking into account that the mechanism of hydrolysis may change when the type of pro-moiety is altered, e.g. n-alkyl vs. t-butyl. Hydrolysis of the phenolic carbonate ester 2-(phenoxycarbonyloxy-acetic acid was increased due to intramolecular catalysis, as compared to the derivatives synthesized from ω-hydroxy carboxylic acids with longer alkyl chains. The carbonate esters appear to be less reactive towards specific acid and base catalyzed hydrolysis than phenyl acetate. The results underline that it is unrealistic to expect that phenolic carbonate ester prodrugs can be utilized in ready to use aqueous formulations. The stability of the carbonate ester derivatives with fatty acid-like structures, expected to interact with the plasma protein human serum albumin, proved sufficient for further in vitro and in vivo evaluation of the potential of utilizing HSA binding in combination with the prodrug approach for optimization of drug pharmacokinetics.

  16. Effect of degree of hydrolysis of whey protein on in vivo plasma amino acid appearance in humans

    Farup, Jean; Rahbek, Stine Klejs; Storm, Adam C; Klitgaard, Søren; Jørgensen, Henry; Bibby, Bo M; Serena, Anja; Vissing, Kristian

    2016-01-01

    Whey protein is generally found to be faster digested and to promote faster and higher increases in plasma amino acid concentrations during the immediate ~60 min following protein ingestion compared to casein. The aim of the present study was to compare three different whey protein hydrolysates...... with varying degrees of hydrolysis (DH, % cleaved peptide bonds) to evaluate if the degree of whey protein hydrolysis influences the rate of amino acid plasma appearance in humans. A casein protein was included as reference. The three differentially hydrolysed whey proteins investigated were: High...... fractions were evaluated in a rat study. A two-compartment model for the description of the postprandial plasma amino acid kinetics was applied to investigate the rate of postprandial total amino acid plasma appearance of the four protein products. The plasma amino acid appearance rates of the three whey...

  17. Structure of Human Acid Sphingomyelinase Reveals the Role of the Saposin Domain in Activating Substrate Hydrolysis.

    Xiong, Zi-Jian; Huang, Jingjing; Poda, Gennady; Pomès, Régis; Privé, Gilbert G

    2016-07-31

    Acid sphingomyelinase (ASM) is a lysosomal phosphodiesterase that catalyzes the hydrolysis of sphingomyelin to produce ceramide and phosphocholine. While other lysosomal sphingolipid hydrolases require a saposin activator protein for full activity, the ASM polypeptide incorporates a built-in N-terminal saposin domain and does not require an external activator protein. Here, we report the crystal structure of human ASM and describe the organization of the three main regions of the enzyme: the N-terminal saposin domain, the proline-rich connector, and the catalytic domain. The saposin domain is tightly associated along an edge of the large, bowl-shaped catalytic domain and adopts an open form that exposes a hydrophobic concave surface approximately 30Å from the catalytic center. The calculated electrostatic potential of the enzyme is electropositive at the acidic pH of the lysosome, consistent with the strict requirement for the presence of acidic lipids in target membranes. Docking studies indicate that sphingomyelin binds with the ceramide-phosphate group positioned at the binuclear zinc center and molecular dynamic simulations indicate that the intrinsic flexibility of the saposin domain is important for monomer-dimer exchange and for membrane interactions. Overall, ASM uses a combination of electrostatic and hydrophobic interactions to cause local disruptions of target bilayers in order to bring the lipid headgroup to the catalytic center in a membrane-bound reaction. PMID:27349982

  18. Enzymatic hydrolysis and fermentability of corn stover pretreated by lactic acid and/or acetic acid

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

    2009-01-01

    Four different pretreatments with and without addition of low concentration organic acids were carried out on corn stover at 195 °C for 15 min. The highest xylan recovery of 81.08% was obtained after pretreatment without acid catalyst and the lowest of 58.78% after pretreatment with both acetic and...

  19. Cholesterol efflux from THP-1 macrophages is impaired by the fatty acid component from lipoprotein hydrolysis by lipoprotein lipase

    Yang, Yanbo; Thyagarajan, Narmadaa; Coady, Breanne M.; Brown, Robert J., E-mail: rbrown@mun.ca

    2014-09-05

    Highlights: • Lipoprotein hydrolysis products were produced by lipoprotein lipase. • Hydrolysis products lowers expression of macrophage cholesterol transporters. • Hydrolysis products reduces expression of select nuclear receptors. • Fatty acid products lowers cholesterol transporters and select nuclear receptors. • Fatty acid products reduces cholesterol efflux from macrophages. - Abstract: Lipoprotein lipase (LPL) is an extracellular lipase that primarily hydrolyzes triglycerides within circulating lipoproteins. Macrophage LPL contributes to atherogenesis, but the mechanisms behind it are poorly understood. We hypothesized that the products of lipoprotein hydrolysis generated by LPL promote atherogenesis by inhibiting the cholesterol efflux ability by macrophages. To test this hypothesis, we treated human THP-1 macrophages with total lipoproteins that were hydrolyzed by LPL and we found significantly reduced transcript levels for the cholesterol transporters ATP binding cassette transporter A1 (ABCA1), ABCG1, and scavenger receptor BI. These decreases were likely due to significant reductions for the nuclear receptors liver-X-receptor-α, peroxisome proliferator activated receptor (PPAR)-α, and PPAR-γ. We prepared a mixture of free fatty acids (FFA) that represented the ratios of FFA species within lipoprotein hydrolysis products, and we found that the FFA mixture also significantly reduced cholesterol transporters and nuclear receptors. Finally, we tested the efflux of cholesterol from THP-1 macrophages to apolipoprotein A-I, and we found that the treatment of THP-1 macrophages with the FFA mixture significantly attenuated cholesterol efflux. Overall, these data show that the FFA component of lipoprotein hydrolysis products generated by LPL may promote atherogenesis by inhibiting cholesterol efflux, which partially explains the pro-atherogenic role of macrophage LPL.

  20. Cholesterol efflux from THP-1 macrophages is impaired by the fatty acid component from lipoprotein hydrolysis by lipoprotein lipase

    Highlights: • Lipoprotein hydrolysis products were produced by lipoprotein lipase. • Hydrolysis products lowers expression of macrophage cholesterol transporters. • Hydrolysis products reduces expression of select nuclear receptors. • Fatty acid products lowers cholesterol transporters and select nuclear receptors. • Fatty acid products reduces cholesterol efflux from macrophages. - Abstract: Lipoprotein lipase (LPL) is an extracellular lipase that primarily hydrolyzes triglycerides within circulating lipoproteins. Macrophage LPL contributes to atherogenesis, but the mechanisms behind it are poorly understood. We hypothesized that the products of lipoprotein hydrolysis generated by LPL promote atherogenesis by inhibiting the cholesterol efflux ability by macrophages. To test this hypothesis, we treated human THP-1 macrophages with total lipoproteins that were hydrolyzed by LPL and we found significantly reduced transcript levels for the cholesterol transporters ATP binding cassette transporter A1 (ABCA1), ABCG1, and scavenger receptor BI. These decreases were likely due to significant reductions for the nuclear receptors liver-X-receptor-α, peroxisome proliferator activated receptor (PPAR)-α, and PPAR-γ. We prepared a mixture of free fatty acids (FFA) that represented the ratios of FFA species within lipoprotein hydrolysis products, and we found that the FFA mixture also significantly reduced cholesterol transporters and nuclear receptors. Finally, we tested the efflux of cholesterol from THP-1 macrophages to apolipoprotein A-I, and we found that the treatment of THP-1 macrophages with the FFA mixture significantly attenuated cholesterol efflux. Overall, these data show that the FFA component of lipoprotein hydrolysis products generated by LPL may promote atherogenesis by inhibiting cholesterol efflux, which partially explains the pro-atherogenic role of macrophage LPL

  1. Monosaccharide-NAIM Derivatives for D-, L-Configurational Analysis

    Chunchi Lin

    2011-01-01

    Full Text Available The D-, L-enantiomeric pairs of common monosaccharides (xylose, ribose, rhamnose, arabinose, fucose, glucose, mannose, galactose, N-acetylgalactosamine, glucuronic acid and galacturonic acid were derivatized with 2,3-naphthalenediamine to form the corresponding D-, L-aldo-NAIM derivatives. A simple and facile capillary electrophoretic method was established for sugar composition analysis by simultaneously determining the migration times of these aldo-NAIMs using borate buffer at high pH (100 mM, pH 9.0. The methodology is also applicable to sialic acid (ketose monosaccharides. The quantitation level of the proposed method was in the 10~500 ppm range and the LOD was 1 ppm. The enantioseparation of D, L pairs of aldo-NAIMs were also achieved by using modified sulfated-a-cyclodextrin as the chiral selector in phosphate buffer (300 mM, pH 3.0. In addition, the combination by reductive amination of amino-aldo-NAIM agent and D-, L-enantiomeric pairs of monosaccharides formed a diastereomeric pair for saccharide configuration analysis. Aldo-NAIM derivatives are thus shown to be rapid and efficient agents for analyzing saccharide compositions and configurations with good linearity and short analysis times via capillary electrophoresis.

  2. Hydrolysis of tanned leather wastes under alkaline, acidic and oxidative conditions

    Botić Tatjana

    2006-01-01

    Full Text Available Different wastes in large quantities are the outcome or the by-product of processes in the tanning industry. The largest part of solid wastes is collagen based and obtained in the reprocessing steps of tanned and non-tanned products. The quality collagen substance obtained from wastes of the leather industry used as a supporting material in many reprocessing industries. Hydrolysis is the basic step of collagen processing, namely the shortening of its polypeptide chain. The main goal of this investigation was to examine the influence of the following parameters on the extent of collagen hydrolysis: type and quantity of reagent used for hydrolysis temperature of hydrolysis, pH, duration of hydrolysis as well as the dimensions of the "shavings" samples. The change of molar mass during hydrolysis was monitored by UV-spectroscopy. Special attention was paid to the dechroming process of the collagen hydrolysate.

  3. Hydrolysis characteristics of sugarcane bagasse pretreated by dilute acid solution in a microwave irradiation environment

    Highlights: ► Pretreatment of sugarcane bagasse via dilute sulfuric acid is studied. ► The concentration of the dilute sulfuric acid is in the range of 0–0.02 M. ► Around 40–44 wt% of bagasse is degraded from the pretreatment. ► Around 80–98% of hemicellulose in bagasse is hydrolyzed. ► The optimal operation of the pretreatment occurs at 0.005 M. - Abstract: Pretreatment of lignocellulosic biomass is of the utmost importance for the development of bioethanol because of the abundance and low cost of lignocelluloses. To figure out the hydrolysis characteristics of sugarcane bagasse in a microwave irradiation environment, the biomass is pretreated by a dilute sulfuric acid solution at 180 °C for 30 min, with the concentration ranging from 0 to 0.02 M. A variety of analyses, including fiber analysis, TGA, XRD, FTIR and HPLC, are employed to aid in understanding the physical and chemical characteristics of residual solid particles and solutions. A higher concentration is conducive to destroying bagasse; however, the buffering capacity possessed by the biomass is also observed in the pretreatment. The experimental results indicate that around 40–44 wt% of bagasse is degraded from the pretreatment in which around 80–98% of hemicellulose is hydrolyzed. In contrast, crystalline cellulose and lignin are hardly affected by the pretreatment. The maximum yields of xylose and glucose as well as the minimum furfural selectivity occur at the acid concentration of 0.005 M. Consequently, the aforementioned concentration is recommended for bagasse pretreatment and bioethanol production.

  4. Optimization studies on acid hydrolysis of oil palm empty fruit bunch fiber for production of xylose.

    Rahman, S H A; Choudhury, J P; Ahmad, A L; Kamaruddin, A H

    2007-02-01

    Oil palm empty fruit bunch fiber is a lignocellulosic waste from palm oil mills. It is a potential source of xylose which can be used as a raw material for production of xylitol, a high value product. The increasing interest on use of lignocellulosic waste for bioconversion to fuels and chemicals is justifiable as these materials are low cost, renewable and widespread sources of sugars. The objective of the present study was to determine the effect of H(2)SO(4) concentration, reaction temperature and reaction time for production of xylose. Batch reactions were carried out under various reaction temperature, reaction time and acid concentrations and Response Surface Methodology (RSM) was followed to optimize the hydrolysis process in order to obtain high xylose yield. The optimum reaction temperature, reaction time and acid concentration found were 119 degrees C, 60 min and 2%, respectively. Under these conditions xylose yield and selectivity were found to be 91.27% and 17.97 g/g, respectively. PMID:16647852

  5. Hydrolysis of Miscanthus for bioethanol production using dilute acid presoaking combined with wet explosion pre-treatment and enzymatic treatment.

    Sørensen, Annette; Teller, Philip J; Hilstrøm, Troels; Ahring, Birgitte K

    2008-09-01

    Miscanthus is a high yielding bioenergy crop. In this study we used acid presoaking, wet explosion, and enzymatic hydrolysis to evaluate the combination of the different pre-treatment methods for bioethanol production with Miscanthus. Acid presoaking is primarily carried out in order to remove xylose prior to wet explosion. The acid presoaking extracted 63.2% xylose and 5.2% glucose. Direct enzymatic hydrolysis of the presoaked biomass was found to give only low sugar yields of 24-26% glucose. Wet explosion is a pre-treatment method that combines wet-oxidation and steam explosion. The effect of wet explosion on non-presoaked and presoaked Miscanthus was investigated using both atmospheric air and hydrogen peroxide as the oxidizing agent. All wet explosion pre-treatments showed to have a disrupting effect on the lignocellulosic biomass, making the sugars accessible for enzymatic hydrolysis. The combination of presoaking, wet explosion, and enzymatic hydrolysis was found to give the highest sugar yields. The use of atmospheric air gave the highest xylose yield (94.9% xylose, 61.3% glucose), while hydrogen peroxide gave the highest glucose yield (82.4% xylose, 63.7% glucose). PMID:18164954

  6. Glutamic acid production from wheat by-products using enzymatic and acid hydrolysis

    Sari, Y.W.; Alting, A.C.; Floris, R.; Sanders, J.P.M.; Bruins, M.E.

    2014-01-01

    Glutamic acid (Glu) has potential as feedstock for bulk chemicals production. It has also been listed as one of the top twelve chemicals derived from biomass. Large amounts of cheaper Glu can be made available by enabling its production from biomass by-products, such as wheat dried distillers grains

  7. Kinetic analysis of waste activated sludge hydrolysis and short-chain fatty acids production at pH 10

    FENG Leiyu; YAN Yuanyuan; CHEN Yinguang

    2009-01-01

    The accumulation of short-chain fatty acids (SCFAs), a preferred carbon source for enhanced biological phosphorus removal microbes, was significantly improved when waste activated sludge (WAS) was fermented at pH 10. The kinetics of WAS hydrolysis and SCFAs production at pH 10 were investigated. It was observed that during WAS anaerobic fermentation at pH 10 the accumulation of SCFAs was limited by the hydrolysis process, and both the hydrolysis of WAS particulate COD and the accumulation of SCFAs followed first-order kinetics. The hydrolysis and SCFAs accumulation rate constants increased with a increasing of temperature from 10 to 35℃, which could be described by the Arrhenius equation. The kinetic data further indicated that SCFAs production at pH 10 was a biological process. Compared with the experiment of pH uncontrolled (blank test), both the rate constants of WAS hydrolysis and SCFAs accumulation at 20℃ were significantly improved when WAS was fermented at pH 10.

  8. Conversion of levulinic acid into γ-valerolactone using Fe3(CO)12: mimicking a biorefinery setting by exploiting crude liquors from biomass acid hydrolysis.

    Metzker, Gustavo; Burtoloso, Antonio C B

    2015-09-28

    The conversion of biomass-derived levulinic acid (LA) into gamma-valerolactone (GVL) using formic acid (FA) and Fe3(CO)12 as the catalyst precursor was achieved in 92% yield. To mimic a biorefinery setting, crude liquor (containing 20% LA) from the acid hydrolysis of sugarcane biomass in a pilot plant facility was directly converted into GVL in good yield (50%), without the need for isolating LA. PMID:26258183

  9. [Determination of docosahexaenoic acid in milk powder by gas chromatography using acid hydrolysis].

    Shao, Shiping; Xiang, Dapeng; Li, Shuang; Xi, Xinglin; Chen, Wenrui

    2015-11-01

    A method to determine docosahexenoic acid (DHA) in milk powder by gas chromatography was established. The milk powder samples were hydrolyzed with hydrochloric acid, extracted to get total fatty acids by Soxhlet extractor, then esterified with potassium hydroxide methanol solution to form methyl esters, and treated with sodium hydrogen sulfate. The optimal experiment conditions were obtained from orthogonal experiment L9(3(3)) which performed with three factors and three levels, and it requires the reaction performed with 1 mol/L potassium hydroxide solution at 25 degrees C for 5 min. The derivative treated with sodium hydrogen sulfate was separated on a column of SP-2560 (100 m x 0.25 mm x 0.20 μm), and determined in 55 min by temperature programming-gas chromatography. Good linearity was obtained in the range 5.0-300 mg/L with the correlation coefficient of 0.999 9. The relative standard deviations (RSDs) were 3.4%, 1.2% and 1.1% for the seven repeated experiments of 10, 50 and 100 mg/L of DHA, respectively. The limit of detection was 2 mg/kg, and the recoveries of DHA were in the range of 90.4%-93.5%. The results are satisfactory through the tests of practical samples. PMID:26939370

  10. Comparative theoretical studies of the phosphomonoester hydrolysis mechanism by purple acid phosphatases.

    Retegan, M; Milet, A; Jamet, H

    2010-07-01

    We present here the first ONIOM (our own n-layered integrated molecular orbital + molecular mechanics method) studies of a purple acid phosphatase enzyme. Our study focused on the structures of the red kidney bean PAP (kbPAP) complexed with phosphate and with phenyl phosphate and on the mechanism of the phenyl phosphate hydrolysis by the enzyme. Density functional theory (DFT) calculations were also performed using models of different sizes for comparison purpose. Results show that the inclusion of three histidine residues, His202, His295, and His296, with their protein surrounding, is crucial to properly describe the coordination of the substrates. They induce a conformation with the substrate closer to the nucleophilic mu-hydroxyde bridge. In the mechanistic study, a transition state is stabilized by a strong hydrogen bond between His202 and the leaving group of the substrate. Consequently, a smaller value for the activation energy barrier is obtained from DFT calculations including this histidine to the same calculations without this histidine. Using the ONIOM method, this activation energy barrier is even more reduced. So the mechanism, which considers the hydroxo group bridging the two metal ions as nucleophile, becomes really convincing, contrary to the results obtained with a small model at the DFT level. PMID:20550096

  11. Valorisation of food waste via fungal hydrolysis and lactic acid fermentation with Lactobacillus casei Shirota.

    Kwan, Tsz Him; Hu, Yunzi; Lin, Carol Sze Ki

    2016-10-01

    Food waste recycling via fungal hydrolysis and lactic acid (LA) fermentation has been investigated. Hydrolysates derived from mixed food waste and bakery waste were rich in glucose (80.0-100.2gL(-1)), fructose (7.6gL(-1)) and free amino nitrogen (947-1081mgL(-1)). In the fermentation with Lactobacillus casei Shirota, 94.0gL(-1) and 82.6gL(-1) of LA were produced with productivity of 2.61gL(-1)h(-1) and 2.50gL(-1)h(-1) for mixed food waste and bakery waste hydrolysate, respectively. The yield was 0.94gg(-1) for both hydrolysates. Similar results were obtained using food waste powder hydrolysate, in which 90.1gL(-1) of LA was produced with a yield and productivity of 0.92gg(-1) and 2.50gL(-1)h(-1). The results demonstrate the feasibility of an efficient bioconversion of food waste to LA and a decentralized approach of food waste recycling in urban area. PMID:26873283

  12. Acid-Promoted Hydrolysis of m-Cl-Phenyl Phosphorotriamidate leading to its Highly Basic Nature by Kinetic Means

    Harish Kumar Amb

    2015-06-01

    Full Text Available Hydrolysis of m-Cl-Phenyl Phosphorotriamidate has been performed in the acid range, 0.01 to 7.0 M –HCl,in 12%AcoH-H2O (v/v at 98(±0.5oC. The continuous second-order rate rise with the absence of a rate maximum in the entire acid range is significant, leading to its highly basic nature. In this respect, it differs from other related(o-Cl-Ph-&p-Cl-Ph- members of the phosphorotriamidate group. The salt effect variable study leads to the presence and reactivity of the two major reactive species with the Neutral Species(I working in the entire acid range; while the Conjugate acid form(II was observed operating between 4.0-7.0 M HCl region only. Both uni-and bi-molecular mechanisms for the two reactive forms with P-N bond fission have been decided for the C-N-P ester. The hydrolysis is shown to be decreased by the action of the series of the nucleophilic reagents and I'shows the optimum effect here. Role of a chloro-group in the unusual meta position in each aryl matix during hydrolysis was particularly the important feature of this study.

  13. Structural Basis for Nucleotide Hydrolysis by the Acid Sphingomyelinase-like Phosphodiesterase SMPDL3A.

    Gorelik, Alexei; Illes, Katalin; Superti-Furga, Giulio; Nagar, Bhushan

    2016-03-18

    Sphingomyelin phosphodiesterase, acid-like 3A (SMPDL3A) is a member of a small family of proteins founded by the well characterized lysosomal enzyme, acid sphingomyelinase (ASMase). ASMase converts sphingomyelin into the signaling lipid, ceramide. It was recently discovered that, in contrast to ASMase, SMPDL3A is inactive against sphingomyelin and, surprisingly, can instead hydrolyze nucleoside diphosphates and triphosphates, which may play a role in purinergic signaling. As none of the ASMase-like proteins has been structurally characterized to date, the molecular basis for their substrate preferences is unknown. Here we report crystal structures of murine SMPDL3A, which represent the first structures of an ASMase-like protein. The catalytic domain consists of a central mixed β-sandwich surrounded by α-helices. Additionally, SMPDL3A possesses a unique C-terminal domain formed from a cluster of four α-helices that appears to distinguish this protein family from other phosphoesterases. We show that SMDPL3A is a di-zinc-dependent enzyme with an active site configuration that suggests a mechanism of phosphodiester hydrolysis by a metal-activated water molecule and protonation of the leaving group by a histidine residue. Co-crystal structures of SMPDL3A with AMP and α,β-methylene ADP (AMPCP) reveal that the substrate binding site accommodates nucleotides by establishing interactions with their base, sugar, and phosphate moieties, with the latter the major contributor to binding affinity. Our study provides the structural basis for SMPDL3A substrate specificity and sheds new light on the function of ASMase-like proteins. PMID:26792860

  14. Effect of Subsequent Dilute Acid and Enzymatic Hydrolysis on Reducing Sugar Production from Sugarcane Bagasse and Spent Citronella Biomass

    Timung, Robinson; Naik Deshavath, Narendra; Goud, Vaibhav V.; Dasu, Venkata V.

    2016-01-01

    This work was aimed at investigating the effect of process parameters on dilute acid pretreatment and enzymatic hydrolysis of spent citronella biomass (after citronella oil extraction) and sugarcane bagasse on total reducing sugar (TRS) yield. In acid pretreatment, the parameters studied were acid concentration, temperature, and time. At the optimized condition (0.1 M H2SO4, 120°C, and 120 min), maximum TRS obtained was 452.27 mg·g−1 and 487.50 mg·g−1 for bagasse and citronella, respectively....

  15. Hydrolysis of solubilized hemicellulose derived from wet-oxidized wheat straw by a mixture of commercial fungal enzyme preparations

    Skammelsen Schmidt, Anette; Thomsen, Alle Belinda; Woidemann, Anders [Risoe National Lab. (Denmark); Tenkanen, Maija [VTT Biotechnology and Food Research (Finland)

    1998-04-01

    The enzymatic hydrolysis of the solubilized hemicellulose fraction from wet-oxidized wheat straw was investigated for quantification purposes. An optimal hydrolysis depends on factors such as composition of the applied enzyme mixture and the hydrolysis conditions (enzyme loading, hydrolysis time, pH-value, and temperature). A concentrated enzyme mixture was used in this study prepared at VTT Biotechnology and Food Research, Finland, by mixing four commercial enzyme preparations. No distinctive pH-value and temperature optima were identified after a prolonged incubation of 24 hours. By reducing the hydrolysis time to 2 hours a temperature optimum was found at 50 deg. C, where a pH-value higher than 5.2 resulted in reduced activity. An enzyme-substrate-volume-ratio of 0.042, a pH-value of 5.0, and a temperature of 50 deg. C were chosen as the best hydrolysis conditions due to an improved monosaccharide yield. The hydrolysis time was chosen to be 24 hours to ensure equilibrium and total quantification. Even under the best hydrolysis conditions, the overall sugar yield from the enzymatic hydrolysis was only 85% of that of the optimal acid hydrolysis. The glucose yield were approximately the same for the two types of hydrolyses, probably due to the high cellulase activity in the VTT-enzyme mixture. For xylose and arabinose the enzymatic hydrolysis yielded only 80% of that of the acid hydrolysis. As the pentoses existed mainly as complex polymers their degradation required many different enzymes, some of which might be missing from the VTT-enzyme mixture. Furthermore, the removal of side-choins from the xylan backbone during the wet-oxidation pretreatment process might enable the hemicellulosic polymers to interact and precipitate, hence, reducing the enzymatic digestibility of the hemicellulose. (au) 8 tabs., 10 ills., 65 refs.

  16. Comparative study of destruction of sodium salt of carboxymethylcellulose in the course of acid hydrolysis under γ-irradiation

    A study was made on the effect of substituent distribution along chain length on hydrolytic and radiation destruction of commercial compound-Na-salt of carboxymethyl cellulose (Na-CMC) with 0.7 substitution degree. Na-CMC was subjected to 60Co γ-irradiation in the air in 0-0.92 MGy dose range; absorbed dose rate was equal to 9.2x10-3 MGy/h. Acidic hydrolysis of Na-CMC was conducted at 100 deg C, 0.09 M HCl during 0.2-4h. Characteristic viscosity and the number of reducing groups were determined in solutions of irradiated and partially hydrolized Na-CMC. It is shown that carboxylmethyl groups produce the protecting effect on glucoside bond breaking during Na-CMC radiation destruction, as in the case of acidic hydrolysis

  17. Effects of waste activated sludge and surfactant addition on primary sludge hydrolysis and short-chain fatty acids accumulation.

    Ji, Zhouying; Chen, Guanlan; Chen, Yinguang

    2010-05-01

    This paper focused on the effects of waste activated sludge (WAS) and surfactant sodium dodecylbenzene sulfonate (SDBS) addition on primary sludge (PS) hydrolysis and short-chain fatty acids (SCFA) accumulation in fermentation. The results showed that sludge hydrolysis, SCFA accumulation, NH(4)(+)-N and PO(4)(3-)-P release, and volatile suspended solids (VSS) reduction were increased by WAS addition to PS, which were further increased by the addition of SDBS to the mixture of PS and WAS. Acetic, propionic and valeric acids were the top three SCFA in all experiments. Also, the fermentation liquids of PS, PS+WAS, and PS+WAS+SDBS were added, respectively, to municipal wastewater to examine their effects on biological municipal wastewater treatment, and the enhancement of both wastewater nitrogen and phosphorus removals was observed compared with no fermentation liquid addition. PMID:20096564

  18. Effect of acid hydrolysis combined with heat moisture treatment on structure and physicochemical properties of corn starch

    Sun, Qingjie; Zhu, Xiaolei; Si, Fumei; Xiong, Liu

    2013-01-01

    Modification of starch led to new products with new desirable properties. Corn starch samples modified by acid hydrolysis combined with heat moisture treatment (AH-HMT) were made by changing pH, moisture content and treated temperature. After modification, swelling power at temperature higher than 75 °C of corn starches decreased while solubility of the starches increased. After AH-HMT, pasting temperature (PT) of all treated starch samples increased. But lower peak viscosity (PKV), trough vi...

  19. Heat integration of an ethanol polygeneration plant based on lignocellulose: Comparing weak acid hydrolysis and enzymatic hydrolysis; Energiintegrerat etanolkombinat baserat paa lignocellulosa - Jaemfoerelse mellan svagsyrahydrolys och enzymhydrolys

    Olsson, Marcus; Nordman, Roger; Taherzadeh, Mohammad

    2011-07-01

    Plants for bioethanol production have been planned in several cities in Sweden, including Boraas. This report provides answers to general questions regarding how such a facility's energy demand is affected by the external integration with a heat and power plant and the internal energy integration between process units. Heat integration of a bioethanol plant means that energy is reused as much as is technically possible; this sets a practical minimum level for the energy demand of the plant. In the study, ethanol production from cellulose has been simulated using Aspen Plus. Weak acid hydrolysis and enzymatic hydrolysis have been simulated, each with 50,000 and 100,000 tonnes of ethanol per year, resulting in four simulation cases. In all cases, heat integration is evaluated using pinch analysis. The steam in the ethanol plant has been covered by steam from a heat and power plant similar to that found today in Boraas. It is important to note that the energy quotas reported here includes energy use for upgrading the residual products. This leads to lower energy quotas than would be the case if the upgrading of residuals were allocated outside of the ethanol production. The conclusions from the project are: - The steam demand of the ethanol plant leads to a reduction in both the electricity and heat production of the heat and power plant. For the weak acid hydrolysis, the electricity loss is relatively high, 26-98%, which will affect the revenue significantly. The loss of electricity production is lower for the enzymatic process: 11-47%. - The difference in decreased electricity between the theoretical case of heating the raw material and the two alternative heating cases is about a factor of two, so the design of the heating of raw material is extremely important. - The reduced heat output of the power plant can, in most cases, be balanced by the surplus heat from the ethanol plant, but to completely balance the shortage, heat over 100 deg C must be used

  20. The Acid Hydrolysis Mechanism of Acetals Catalyzed by a Supramolecular Assembly in Basic Solution

    Pluth, Michael D.; Bergman, Robert G.; Raymond, Kenneth N.

    2008-09-24

    A self-assembled supramolecular host catalyzes the hydrolysis of acetals in basic aqueous solution. The mechanism of hydrolysis is consistent with the Michaelis-Menten kinetic model. Further investigation of the rate limiting step of the reaction revealed a negative entropy of activation ({Delta}S{double_dagger} = -9 cal mol{sup -1}K{sup -1}) and an inverse solvent isotope effect (k(H{sub 2}O)/k(D{sub 2}O) = 0.62). These data suggest that the mechanism of hydrolysis that takes place inside the assembly proceeds through an A-2 mechanism, in contrast to the A-1 mechanism operating in the uncatalyzed reaction. Comparison of the rates of acetal hydrolysis in the assembly with the rate of the reaction of unencapsulated substrates reveals rate accelerations of up to 980 over the background reaction for the substrate diethoxymethane.

  1. Targeting and Imaging of Cancer Cells via Monosaccharide-Imprinted Fluorescent Nanoparticles

    Wang, Shuangshou; Yin, Danyang; Wang, Wenjing; Shen, Xiaojing; Zhu, Jun-Jie; Chen, Hong-Yuan; Liu, Zhen

    2016-03-01

    The recognition of cancer cells is a key for cancer diagnosis and therapy, but the specificity highly relies on the use of biorecognition molecules particularly antibodies. Because biorecognition molecules suffer from some apparent disadvantages, such as hard to prepare and poor storage stability, novel alternatives that can overcome these disadvantages are highly important. Here we present monosaccharide-imprinted fluorescent nanoparticles (NPs) for targeting and imaging of cancer cells. The molecularly imprinted polymer (MIP) probe was fluorescein isothiocyanate (FITC) doped silica NPs with a shell imprinted with sialic acid, fucose or mannose as the template. The monosaccharide-imprinted NPs exhibited high specificity toward the target monosaccharides. As the template monosaccharides used are over-expressed on cancer cells, these monosaccharide-imprinted NPs allowed for specific targeting cancer cells over normal cells. Fluorescence imaging of human hepatoma carcinoma cells (HepG-2) over normal hepatic cells (L-02) and mammary cancer cells (MCF-7) over normal mammary epithelial cells (MCF-10A) by these NPs was demonstrated. As the imprinting approach employed herein is generally applicable and highly efficient, monosaccharide-imprinted NPs can be promising probes for targeting cancer cells.

  2. Pretreatment by extremely low acid hydrolysis combed with enzymolysis improving saccharification efficiency of corn stalk%超低酸预处理结合酶解提高玉米秸秆糖化效率

    曹焱鑫; 邵丽杰; 张欢; 寇巍; 王晓明; 张大雷

    2014-01-01

    Corn straw is one of the most abundant agricultural and forest residues containing cellulose, hemicellulose, and lignin. About 2.24×108 tons of corn straw are produced per year in china, most of which is burned or lost in farmland, and only a small part is used as feed for livestock. Because corn straw is abundant in cellulose, it can be used as a substitute for grain to produce fuel-ethanol, which can be a significant contribution for relieving the crisis of resource and foodstuff shortage. The process of producing fuel-ethanol includes pretreatment, enzymatic hydrolysis, fermentation, and distillation. Cellulose, hemicellulose, and lignin in corn straw form stable polymers, which hardly dissolve in water, dilute acid, dilute alkali, and most organic solutions. Each component interrelates with all the others. Because of the complex configuration, hemicellulose and lignin will hinder the degradation of cellulose. To utilize the cellulose, corn straw must be pretreated. To improve the reduction of sugar yield in corn straw, the hydrolysis method of using extremely low sulfuric acid followed by enzymolysis is employed to treat corn stalk. To investigate the mechanism of reducing sugar conversion in acid hydrolysis and enzymolysis, the yield of totally reduced sugar, glucose and xylose was analyzed with acid hydrolysis followed by enzymolysis under different acid concentrations, temperatures and reaction times. Acid concentrations 0.1%, 160℃, 55 min, 180 r/min, solid-liquid ratio 1:10 was confirmed by orthogonal experiment. Through acid hydrolysis followed by enzymolysis (enzyme 5.0%, pH 4.6, 24 h, 50℃), the yield of totally reduced sugar, glucose, and xylose was 56.22%, 16.97%and 18.83%, respectively. The concentration of totally reduced sugar, glucose, and xylose was 62.46, 18.85 and 20.92 g/L, respectively. After acid hydrolysis and enzymolysis treatment, the corn stalk component was analyzed by infrared spectral and the Van Soest methods. The conversion of

  3. The effect of acid hydrolysis on the technological functional properties of pinhão (Araucaria brasiliensis) starch

    Roberta Cruz Silveira Thys; Andréia Gomes Aires; Ligia Damasceno Ferreira Marczak; Caciano Pelayo Zapata Noreña

    2013-01-01

    Technological functional properties of native and acid-thinned pinhão (seeds of Araucária angustifolia, Brazilian pine) starches were evaluated and compared to those of native and acid-thinned corn starches. The starches were hydrolyzed (3.2 mol.L-1 HCl, 44 ºC, 6 hours) and evaluated before and after the hydrolysis reaction in terms of formation, melting point and thermo-reversibility of gel starches, retrogradation (in a 30-day period and measurements every three days), paste freezing and th...

  4. Production of nanocrystalline cellulose from an empty fruit bunches using sulfuric acid hydrolysis: Effect of reaction time on the molecular characteristics

    Al-Dulaimi, Ahmed A.; R, Rohaizu; D, Wanrosli W.

    2015-06-01

    Nanocrystalline cellulose (NCC) was isolated from OPEFB pulp via sulfuric acid hydrolysis. The influence of reaction time to the molecular weight and surface charge of the NCC was investigated. Characterization of the product was carried out using zeta potential measurement and gel permeation chromatography test. Zeta potential measurement showed that the surface negative charge significantly increases with increasing reaction time. Gel permeation chromatography test indicates that molecular weight of NCC change variably with increasing of hydrolysis time. (Keywords: Nanocrystalline cellulose; acid hydrolysis; sulfate content; molecular weight)

  5. Hydrolysis and transesterification of parabens in an aqueous solution in the presence of glycerol and boric acid

    Oldrich Farsa

    2011-06-01

    Full Text Available In a solution containing 0.067% methylparaben, 0.033% propylparaben, 3.4% glycerol and 2.0% boric acid,concentrations of both parabens, 4-hydroxybenzoic acid and 2,3-dihydroxypropyl 4-hydroxybenzoate weremonitored for up to 68 months storage. 4-hydroxybenzoic acid is the main hydrolysis product of parabens,while 2,3-dihydroxypropyl 4-hydroxybenzoate was proposed as the main product of transesterification of parabens with glycerol. Results of an HPLC evaluation of parabens, 4-hydroxybenzoic acid and 2,3-dihydroxypropyl 4-hydroxybenzoate showed that the decomposition of 68 months old samples stored at room temperature did not exceed 2.0%. The stability of both parabens in a medicinal preparation of the statedcomposition has thus been satisfactorily demonstrated after more than 5 years of storage under ambient conditions. The transesterification reaction was shown to influence the chemical stability of parabens to an extent comparable to hydrolysis. Moreover, the presence of 2,3-dihydroxypropyl 4-hydroxybenzoate in the solution containing glycerol and boric acid was confirmed by 1H-NMR spectroscopy.

  6. Isolation of bacterial cellulose nanocrystalline from pineapple peel waste: Optimization of acid concentration in the hydrolysis method

    Anwar, Budiman; Rosyid, Nurul Huda; Effendi, Devi Bentia; Nandiyanto, Asep Bayu Dani; Mudzakir, Ahmad; Hidayat, Topik

    2016-02-01

    Isolation of needle-shaped bacterial cellulose nanocrystalline with a diameter of 16-64 nm, a fiber length of 258-806 nm, and a degree of crystallinity of 64% from pineapple peel waste using an acid hydrolysis process was investigated. Experimental showed that selective concentration of acid played important roles in isolating the bacterial cellulose nanocrystalline from the cellulose source. To achieve the successful isolation of bacterial cellulose nanocrystalline, various acid concentrations were tested. To confirm the effect of acid concentration on the successful isolation process, the reaction conditions were fixed at a temperature of 50°C, a hydrolysis time of 30 minutes, and a bacterial cellulose-to-acid ratio of 1:50. Pineapple peel waste was used as a model for a cellulose source because to the best of our knowledge, there is no report on the use of this raw material for producing bacterial cellulose nanocrystalline. In fact, this material can be used as an alternative for ecofriendly and cost-free cellulose sources. Therefore, understanding in how to isolate bacterial cellulose nanocrystalline from pineapple peel waste has the potential for large-scale production of inexpensive cellulose nanocrystalline.

  7. [The use of enzymatic hydrolysis for isolation of barbituric acid derivatives from blood (as exemplified by phenobarbital and barbamyl)].

    Chuvina, N A; Kolupaeva, A S; Strelova, O Iu; Zabolotskaia, I V; Gorbacheva, T V

    2010-01-01

    Modern isolation techniques by direct extraction with organic solvents or after protein precipitation by various sedimenting or salting-out agents are characterized by low efficiency and do not permit to liberate derivatives of barbituric acid from their complexes with blood proteins. The use of enzymatic hydrolysis makes it possible to break bonds between barbiturates and protein and thereby improve the efficiency of isolation. We performed enzymatic hydrolysis of the model phenobarbital-blood and barbamyl-blood complexes with the use of trypsin, pepsin, chymotrypsin, and papain. The degree of phenobarbital extraction with trypsin and barbamyl was estimated at 62.1 +/- 1.2% and 75.1 +/- 1.6% respectively; in other words, it was 32.7 +/- 1.0% and 51.1 +/- 1.0% higher than that achieved by traditional methods. Certain validation characteristics of the new method are presented. PMID:21265178

  8. Molecular mechanism of acid-catalyzed hydrolysis of peptide bonds using a model compound.

    Pan, Bin; Ricci, Margaret S; Trout, Bernhardt L

    2010-04-01

    The stability of peptide bonds is a critical aspect of biological chemistry and therapeutic protein applications. Recent studies found elevated nonenzymatic hydrolysis in the hinge region of antibody molecules, but no mechanism was identified. As a first step in providing a mechanistic interpretation, this computational study examines the rate-determining step of the hydrolytic reaction of a peptide bond under acidic pH by a path sampling technique using a model compound N-MAA. Most previous computational studies did not include explicit water molecules, whose effects are significant in solution chemistry, nor did they provide a dynamic picture for the reaction process in aqueous conditions. Because no single trajectory can be used to describe the reaction dynamics due to fluctuations at finite temperatures, a variant version of the transition path sampling technique, the aimless shooting algorithm, was used to sample dynamic trajectories and to generate an ensemble of transition trajectories according to their statistical weights in the trajectory space. Each trajectory was computed as the time evolution of the molecular system using the Car-Parrinello molecular dynamics technique. The likelihood maximization procedure and its modification were used in extracting dynamically relevant degrees of freedom in the system, and approximations of the reaction coordinate were compared. Its low log-likelihood score and poor p(B) histogram indicate that the C-O distance previously assumed as the reaction coordinate for the rate-determining step is inadequate in describing the dynamics of the reaction. More than one order parameter in a candidate set including millions of geometric quantities was required to produce a convergent reaction coordinate model; its involvement of many degrees of freedom suggests that this hydrolytic reaction step is very complex. In addition to affecting atoms directly involved in bond-making and -breaking processes, the water network also has

  9. Assay of phenolic compounds from four species of ber (Ziziphus mauritiana L.) fruits: comparison of three base hydrolysis procedure for quantification of total phenolic acids.

    Memon, Ayaz Ali; Memon, Najma; Bhanger, Muhammad Iqbal; Luthria, Devanand L

    2013-08-15

    The present study was undertaken to investigate the flavonoid profile in four species of ber (Ziziphus mauritiana Lamk.) fruit. The 12 flavonoids identified were quercetin 3-O-robinobioside, quercetin 3-O-rutinoside, quercetin 3'-O-galactoside, quercetin 3'-O-glucoside, quercetin 3'-O-rhamnoside, quercetin 3'-O-pentosylhexoside, quercetin 3-O-6'malonylglucoside, quercetin 3'-O-malonylglucoside, luteolin 7-O-6'malonylglucoside, luteolin 7-O-malonylglucoside, myricetin 3-O-galactoside, and naringenin tri glycoside. This is the first report on extraction of nine additional flavonoids from the ber fruits. In addition, we also compared the impact of three different base hydrolysis techniques namely ultrasonic assisted base hydrolysis (UABH), microwave assisted base hydrolysis (MWABH), and pressurised liquid assisted base hydrolysis (PLABH) for the quantification of total phenolic acids. Nine phenolic acids, protocatechuic acid, p-hydroxybenzoic acid, ferulic acid, chlorogenic acid, vanillic acid, caffeic acid, vanillin, ortho- and para-coumaric acids, were identified and quantified. The three major phenolic acids identified in all four ber species were p-coumaric acid, vanillin and ferulic acids. Higher amounts (pacids in all cultivars were obtained with the PLABH technique as compared to other two procedures (UABH and MWABH). PMID:23561136

  10. Hydrolysis of Cellulose Using Mono-Component Enzymes Shows Synergy during Hydrolysis of Phosphoric Acid Swollen Cellulose (PASC), but Competition on Avicel

    Andersen, Natalija; Johansen, Katja S.; Michelsen, Michael Locht; Stenby, Erling Halfdan; Krogh, Kristian B.R.M.; Olsson, Lisbeth

    2008-01-01

    ). In contrast to previous studies, where P-glucosidase was either not added or added in excess, we here focus on engineering binary, as well as, ternary cellulase mixtures (including a range of different mol% of Cel3A) for maximal total sugar production. Precise hydrolysis pattern based on the...... concentration of soluble hydrolysis products (glucose to cellohexaose measured by HPLC) was determined. The importance of proper assay selection for hydrolysis products detection was illustrated. It was found that degree of synergy (DS) for degradation of PASC were generally larger than I (indicating...

  11. Microwave-assisted hydrolysis of organophosphate pesticides leading to their total decomposition up to phosphoric acid

    Čechová, Lucie; Jansa, Petr; Dračínský, Martin; Janeba, Zlatko

    Thessaly: University of Thessaly, 2012. A12-A12. [International Symposium on green chemistry for environment, health and development /3./. 03.10.2012-05.10.2012, Skiathos Island] R&D Projects: GA MV VG20102015046 Institutional research plan: CEZ:AV0Z40550506 Keywords : microwave-assisted hydrolysis * organo Subject RIV: CC - Organic Chemistry

  12. Kinetic Studies on Wheat Straw Hydrolysis to Levulinic Acid%小麦秸秆制备乙酰丙酸的动力学研究

    常春; 马晓建; 岑沛霖

    2009-01-01

    Levulinic acid is considered as a promising green platform chemical derived from biomass. The kinetics of levulinic acid accumulation in the hydrolysis process of wheat straw was investigated in the study. Using dilute sulfuric acid as a catalyst, the kinetic experiments were performed in a temperature range of 190-230℃ and an acid concentration range of 1%-5% (by mass). A simple model of first-order series reactions was developed, which provided a satisfactory interpretation of the experimental results. The kinetics of main intermediates including sugar and 5-hydroxymethylfurfural (5-HMF) were also established. The kinetic parameters provided useful information for understanding the hydrolysis process.

  13. Integration of mild acid hydrolysis in γ-valerolactone/water system for enhancement of enzymatic saccharification from cotton stalk.

    Wu, Miao; Yan, Zhong Ya; Zhang, Xue Ming; Xu, Feng; Sun, Run Cang

    2016-01-01

    In this study, mild acid hydrolysis using γ-valerolactone (GVL)/water system integrated with enzymatic hydrolysis was carried out for the enhancement of enzymatic saccharification efficiency. The quantitative analysis of soluble carbohydrates and structural characterizations of solid residues were conducted. Results showed that the soluble carbohydrates in the water-phase were mainly composed of monomers and oligomers from xylose and glucose, while the contents of which were depended on the ratio of GVL to water. Moreover, the inhibitors were hardly detected due to the moderate pretreatment severity. Compared with the untreated feedstock, the yields of enzymatic hydrolysis from pretreated samples increased by two-fold with the mixture of 80/20 GVL/H2O. Combined with the amount of glucose (14.6%) dissolved in the water-phase, over 92.6% of glucose in cotton stalk was released and recovered. Based on the comprehensive analysis, treatment with GVL/H2O system provided us a more effective approach for sugar production from biomass. PMID:26476160

  14. The effect of acid hydrolysis on the technological functional properties of pinhão (Araucaria brasiliensis starch

    Roberta Cruz Silveira Thys

    2013-02-01

    Full Text Available Technological functional properties of native and acid-thinned pinhão (seeds of Araucária angustifolia, Brazilian pine starches were evaluated and compared to those of native and acid-thinned corn starches. The starches were hydrolyzed (3.2 mol.L-1 HCl, 44 ºC, 6 hours and evaluated before and after the hydrolysis reaction in terms of formation, melting point and thermo-reversibility of gel starches, retrogradation (in a 30-day period and measurements every three days, paste freezing and thawing stability (after six freezing and thawing cycles, swelling power, and solubility. The results of light transmittance (% of pastes of native and acid-thinned pinhão starches was higher (lower tendency to retrogradation than that obtained for corn starches after similar storage period. Native pinhão starch (NPS presented lower syneresis than native corn starch (NCS when submitted to freeze-thaw cycles. The acid hydrolysis increased the syneresis of the two native varieties under storage at 5 ºC and after freezing and thawing cycles. The solubility of NPS was lower than that of native corn starch at 25, 50, and 70 ºC. However, for the acid-thinned pinhão starch (APS, this property was significantly higher (p < 0.05 when compared to that of acid-thinned corn starch (ACS. From the results obtained, it can be said that the acid treatment was efficient in producing a potential fat substitute from pinhão starch variety, but this ability must be further investigated.

  15. Metal Enhanced Interactions of Graphene with Monosaccharides

    Pereyda-Pierre, C.; A. F. Jalbout

    2016-01-01

    The present theoretical study proposes the enhanced interaction of nanostructures with monosaccharides. It has been demonstrated that the interactions with and without metal adsorption do in fact show that the adsorption energies change accordingly. It is important to note that the chemistry of reactions can also be influenced as a result of this change in dynamics.

  16. Enhanced enzymatic hydrolysis of poplar bark by combined use of gamma ray and dilute acid for bioethanol production

    Chung, Byung Yeoup; Lee, Jae Taek; Bai, Hyoung-Woo; Kim, Ung-Jin; Bae, Hyeun-Jong; Gon Wi, Seung; Cho, Jae-Young

    2012-08-01

    Pretreatment of poplar bark with a combination of sulfuric acid (3%, w/w, H2SO4) and gamma irradiation (0-1000 kGy) was performed in an attempt to enhance enzymatic hydrolysis for bioethanol production. The yields of reducing sugar were slightly increased with an increasing irradiation dose, ranging from 35.4% to 51.5%, with a 56.1% reducing sugar yield observed after dilute acid pretreatment. These results clearly showed that soluble sugars were released faster and to a greater extent in dilute acid-pretreated poplar bark than in gamma irradiation-pretreated bark. When combined pretreatment was carried out, a drastic increase in reducing sugar yield (83.1%) was found compared with individual pretreatment, indicating the possibility of increasing the convertibility of poplar bark following combined pretreatment. These findings are likely associated with cellulose crystallinity, lignin modification, and removal of hemicelluloses.

  17. Hydrolysis of tanned leather wastes under alkaline, acidic and oxidative conditions

    Botić Tatjana; Ilišković Nadežda

    2006-01-01

    Different wastes in large quantities are the outcome or the by-product of processes in the tanning industry. The largest part of solid wastes is collagen based and obtained in the reprocessing steps of tanned and non-tanned products. The quality collagen substance obtained from wastes of the leather industry used as a supporting material in many reprocessing industries. Hydrolysis is the basic step of collagen processing, namely the shortening of its polypeptide chain. The main goal of this i...

  18. [Optimization of liquid ammonia treatment for enzymatic hydrolysis of Saccharum arundinaceum to fermentable sugars].

    Liu, Jianjun; Peng, Hehuan; Zhao, Xiangjun; Cheng, Cheng; Chen, Feng; Shao, Qianjun

    2013-03-01

    China has abundant available marginal land that can be used for cultivation of lignocellulosic energy plants. Saccharum arundinaceum Retz. is a potential energy crop with both high biomass yield and low soil fertility requirements. It can be planted widely as cellulosic ethanol feedstock in southern China. In the present work Saccharum arundinaceum was pretreated by liquid ammonia treatment (LAT) to overcome biomass recalcitrance, followed by enzymatic hydrolysis. The monosaccharide contents (glucose, xylose, and arabinose) of the enzymatic hydrolysate were determined by high performance liquid chromatography. Experimental results show that the optimal LAT pretreatment conditions were 130 0C, 2:1 (W/W) ammonia to biomass ratio, 80% moisture content (dry weight basis) and 5 min residence time. Approximately 69.34% glucan and 82.60% xylan were converted after 72 h enzymatic hydrolysis at 1% glucan loading using 15 FPU/(g of glucan) of cellulase. The yields of glucose and xylose were 573% and 1 056% higher than those of the untreated biomass, and the LAT-pretreated substrates obtained an 8-fold higher of total monosaccharide yield than untreated substrates. LAT pretreatment was an effective to increase the enzymatic digestibility of Saccharum arundinaceum compared to acid impregnated steam explosion and similar to that of acid treatment and ammonia fiber expansion treatment. PMID:23789274

  19. Electricity production from twelve monosaccharides using microbial fuel cells

    Catal, Tunc; Li, Kaichang; Bermek, Hakan; Liu, Hong

    Direct generation of electricity from monosaccharides of lignocellulosic biomass was examined using air cathode microbial fuel cells (MFCs). Electricity was generated from all carbon sources tested, including six hexoses (D-glucose, D-galactose, D(-)-levulose (fructose), L-fucose, L-rhamnose, and D-mannose), three pentoses (D-xylose, D(-)-arabinose, and D(-)-ribose), two uronic acids (D-galacturonic acid and D-glucuronic acid) and one aldonic acid (D-gluconic acid). The mixed bacterial culture, which was enriched using acetate as a carbon source, adapted well to all carbon sources tested, although the adaptation times varied from 1 to 70 h. The maximum power density obtained from these carbon sources ranged from 1240 ± 10 to 2770 ± 30 mW m -2 at current density range of 0.76-1.18 mA cm -2. D-Mannose resulted in the lowest maximum power density, whereas D-glucuronic acid generated the highest one. Coulombic efficiency ranged from 21 to 37%. For all carbon sources tested, the relationship between the maximum voltage output and the substrate concentration appeared to follow saturation kinetics at 120 Ω external resistance. The estimated maximum voltage output ranged between 0.26 and 0.44 V and half-saturation kinetic constants ranged from 111 to 725 mg L -1. Chemical oxygen demand (COD) removal was over 80% for all carbon sources tested. Results from this study indicated that lignocellulosic biomass-derived monosaccharides might be a suitable resource for electricity generation using MFC technology.

  20. Electricity production from twelve monosaccharides using microbial fuel cells

    Catal, Tunc [Department of Biological and Ecological Engineering, Oregon State University, 116 Gilmore Hall, Corvallis, OR 97331 (United States); Department of Wood Science and Engineering, Oregon State University, 102 Richardson Hall, Corvallis, OR 97331 (United States); Department of Molecular Biology and Genetics, Istanbul Technical University, 34469-Maslak, Istanbul (Turkey); Li, Kaichang [Department of Wood Science and Engineering, Oregon State University, 102 Richardson Hall, Corvallis, OR 97331 (United States); Bermek, Hakan [Department of Molecular Biology and Genetics, Istanbul Technical University, 34469-Maslak, Istanbul (Turkey); Liu, Hong [Department of Biological and Ecological Engineering, Oregon State University, 116 Gilmore Hall, Corvallis, OR 97331 (United States)

    2008-01-03

    Direct generation of electricity from monosaccharides of lignocellulosic biomass was examined using air cathode microbial fuel cells (MFCs). Electricity was generated from all carbon sources tested, including six hexoses (D-glucose, D-galactose, D(-)-levulose (fructose), L-fucose, L-rhamnose, and D-mannose), three pentoses (D-xylose, D(-)-arabinose, and D(-)-ribose), two uronic acids (D-galacturonic acid and D-glucuronic acid) and one aldonic acid (D-gluconic acid). The mixed bacterial culture, which was enriched using acetate as a carbon source, adapted well to all carbon sources tested, although the adaptation times varied from 1 to 70 h. The maximum power density obtained from these carbon sources ranged from 1240 {+-} 10 to 2770 {+-} 30 mW m{sup -2} at current density range of 0.76-1.18 mA cm{sup -2}. D-Mannose resulted in the lowest maximum power density, whereas D-glucuronic acid generated the highest one. Coulombic efficiency ranged from 21 to 37%. For all carbon sources tested, the relationship between the maximum voltage output and the substrate concentration appeared to follow saturation kinetics at 120 {omega} external resistance. The estimated maximum voltage output ranged between 0.26 and 0.44 V and half-saturation kinetic constants ranged from 111 to 725 mg L{sup -1}. Chemical oxygen demand (COD) removal was over 80% for all carbon sources tested. Results from this study indicated that lignocellulosic biomass-derived monosaccharides might be a suitable resource for electricity generation using MFC technology. (author)

  1. Effect of acid hydrolysis combined with heat moisture treatment on structure and physicochemical properties of corn starch.

    Sun, Qingjie; Zhu, Xiaolei; Si, Fumei; Xiong, Liu

    2015-01-01

    Modification of starch led to new products with new desirable properties. Corn starch samples modified by acid hydrolysis combined with heat moisture treatment (AH-HMT) were made by changing pH, moisture content and treated temperature. After modification, swelling power at temperature higher than 75 °C of corn starches decreased while solubility of the starches increased. After AH-HMT, pasting temperature (PT) of all treated starch samples increased. But lower peak viscosity (PKV), trough viscosity (TV) and break down (BD) of most treated starch samples were observed. AH-HMT increased the gel hardness of all treated starches. And the biggest hardness of modified starch gel was 148.419 g, improving 93.471 g compared with native starch gel. The melting temperatures (To, Tp, Tc) of modified starch increased, but the melting range and △H decreased. The X-ray pattern remained practically unchanged with or without AH-HMT. Acid hydrolysis combined with heat moisture treatment (AH-HMT) improved the functional properties of corn starch. PMID:25593372

  2. G-lignin and hemicellulosic monosaccharides distinctively affect biomass digestibility in rapeseed.

    Pei, Yanjie; Li, Yuyang; Zhang, Youbing; Yu, Changbing; Fu, Tingdong; Zou, Jun; Tu, Yuanyuan; Peng, Liangcai; Chen, Peng

    2016-03-01

    In this study, total 19 straw samples from four Brassica species were determined with a diverse cell wall composition and varied biomass enzymatic digestibility under sulfuric acid or lime pretreatment. Correlation analysis was then performed to detect effects of cell wall compositions and wall polymer features (cellulose crystallinity, hemicellulosic monosaccharides and lignin monomers) on rapeseeds biomass digestibility. As a result, coniferyl alcohol (G-lignin) showed a strongly negative effect on biomass saccharification, whereas hemicellulosic monosaccharides (fucose, galactose, arabinose and rhamnose) were positive factors on lignocellulose digestions. Notably, chemical analyses of four typical pairs of samples indicated that hemicellulosic monosaccharides and G-lignin may coordinately influence biomass digestibility in rapeseeds. In addition, Brassica napus with lower lignin content exhibited more efficiency on both biomass enzymatic saccharification and ethanol production, compared with Brassica junjea. Hence, this study has at first time provided a genetic strategy on cell wall modification towards bioenergy rapeseed breeding. PMID:26748046

  3. 柱前衍生高效液相色谱法分析海带岩藻聚糖的单糖及糖醛酸组成%Analysis of Monosaccharides and Uronic Acids in Fucoidon from Seaweed by Pre-column Derivatization High Performance Liquid Chromatography

    王泽文; 冷凯良; 孙伟红; 翟毓秀; 邢丽红; 苗钧魁

    2011-01-01

    High performance liquid chromatography (HPLC) was employed for the analysis of monosaccharide and uronic acids in fucoidon from fresh seaweed with pre-column derivatization. After degradated by 4 mol/L trifluoroacetic acid and derivatived with 1-phenyl-3-methyl-5-pyrazolone(PMP),monosaccharides and uronic acids in fucoidon were separated by reversed-phase HPLC with gradient elution, and monitored by ultraviolet detector at 250 nm. The result show that fucoidon consists of 5 kinds of monosaccharides and 2 kinds of uronic acids. The ratio of mannose, rhamnose, glucuronic acid,galacturonic acid, glucose, galactoses, fucose is 0.03:3.7:0. 22:0.74:0.12: 1.1: 4.1. The developed method is suitable for the rapid analysis of polysaccharide with good reproducibility.%建立了一种柱前衍生高效液相色谱法同时测定海带中岩藻聚糖的单糖及糖醛酸组成的方法.岩藻聚糖经4 mol/L三氟乙酸降解后,用1-苯基-3-甲基-5-吡唑啉酮(PMP)进行衍生化,并采用配有紫外检测器的反相高效液相色谱仪在250 nm波长下进行测定,实现了7种单糖和糖醛酸的良好分离.结果表明:该岩藻聚糖样品由5种单糖和2种糖醛酸组成,其物质量之比为甘露糖:鼠李糖:葡萄糖醛酸:半乳糖醛酸:葡萄糖:半乳糖:岩藻糖=0.03:3.7:0.22:0.74:0.12:1.1:4.1.该方法重现性良好,能够快速对多糖样品进行组成分析.

  4. Characteristics of Bone Gelatin Tilapia (Oreochromis niloticus Processed by Using Hydrolysis With Phosphoric Acid and Papain Enzyme

    Gugun Hidayat

    2016-04-01

    Full Text Available Phosphoric acid and papain enzyme able to hydrolyzing collagen from Tilapia into gelatin . The purpose of this research was to determine the best concentration of phosphoric acid and papain enzyme and to determine the physicochemical characteristic gelatin to from Tilapia fish bone which processed with phosphoric acid and papain enzyme. The first research phase was making bone gelatin tilapia using phosphoric acid at concentration of 4%, 5% and 6%, and the papain enzyme 0.5%, 1% and 1.5%. The second phase was characterize the physicochemical gelatin from the best concentration of phosphoric acid concentration (6% and papain enzyme (1.5%, all treatment done with three repetitions. Analysis of the data using ANOVA with completely randomized (CRD design If there was difference between treatment then continued with Honestly Significant Difference Test (HSDT. The results of the first research phase found the best concentration were 6% of phosphoric acid and 1.5% papain enzyme, its shows by the value gel strength 325,95 and 373,32 g.bloom. The second research phase shows that the the best results obtained in this study was gelatin from 1.5% papain enzyme as hydrolysis agent, the physicochemical characteristic were: 376.21 g.bloom gel strength; viscosity of 7.57 cP; yield 6.30%; protein content of 86.46%; water content of 7.12%; and the pH value of 5.11.

  5. Monosaccharide analysis of succulent leaf tissue in Aloe

    Grace, Olwen Megan; Dzajic, Amra; Jäger, Anna;

    2013-01-01

    genus Aloe using a predictive phylogenetic approach. Methodology – Monosaccharide composition was assessed in 31species, representing the morphological and taxonomic diversity of Aloe sensu stricto. Leaf mesophyll polysaccharides were partially hydrolysed in a trifluoroacetic acid (TFA)-SilA assay...

  6. Redox cycles of vitamin E: Hydrolysis and ascorbic acid dependent reduction of 8a-(alkyldioxy)tocopherones

    Liebler, D.C.; Kaysen, K.L.; Kennedy, T.A. (Univ. of Arizona, Tucson (USA))

    1989-12-12

    Oxidation of the biological antioxidant {alpha}-tocopherol (vitamin E; TH) by peroxyl radicals yields 8a-(alkyldioxy)tocopherones, which either may hydrolyze to {alpha}-tocopheryl quinone (TQ) or may be reduced by ascorbic acid to regenerate TH. To define the chemistry of this putative two-electron TH redox cycle, we studied the hydrolysis and reduction of 8a-((2,4-dimethyl-1-nitrilopent-2-yl)dioxyl)tocopherone (1) in acetonitrile/buffer mixtures and in phospholipid liposomes. TQ formation in acetonitrile/buffer mixtures, which was monitored spectrophotometrically, declined with increasing pH and could not be detected above pH 4. The rate of TQ formation from 1 first increased with time and then decreased in a first-order terminal phase. Rearrangement of 8a-hydroxy-{alpha}-tocopherone (2) to TQ displayed first-order kinetics identical with the terminal phase for TQ formation from 1. Both rate constants increased with decreasing pH. Hydrolysis of 1 in acetonitrile/H{sub 2}{sup 18}O yielded ({sup 18}O)TQ. These observations suggest that 1 loses the 8a-(alkyldioxy) moiety to produce the tocopherone cation (T{sup +}), which hydrolyzes to 2, the TQ-forming intermediate. Incubation of either 1 or 2 with ascorbic acid in acetonitrile/buffer yielded TH. Reduction of both 1 and 2 decreased with increasing pH. In phosphatidylcholine liposomes at pH 7, approximately 10% of the T{sup +} generated from 1 was reduced to TH by 5 mM ascorbic acid. The results collectively demonstrate that T{sup +} is the ascorbic acid reducible intermediate in a two-electron TH redox cycle, a process that probably would require biocatalysis to proceed in biological membranes.

  7. Fundamental study of the mechanism and kinetics of cellulose hydrolysis by acids and enzymes

    Gong, C. S.; Chang, M.

    1981-02-01

    There are three basic enzymes e.g., endoglucanase (C/sub x/), exoglucanase (C1) and cellobiase comprising the majority of extracellular cellulase enzymes produced by the cellulolytic mycelial fungi, Trichoderma reesei, and other cellulolytic microorganisms. The kinetics of cellobiase were developed on the basis of applying the pseudo-steady state assumption to hydrolyze cellobiose to glucose. The results indicated that cellobiase was bjected to end-product inhibition by glucose. The kinetic modeling of exoglucanase (C1) with respect to cellodextrins was studied. Both glucose and cellobiose were found to be inhibitors of this enzyme with cellobiose being a stronger inhibitor than glucose. Similarly, endoglucanase (C/sub x) is subject to end-product inhibition by glucose. Crystallinity of the cellulose affects the rate of hydrolysis by cellulases. Hence, the changes in crystallinity of cellulose in relation to chemical pretreatment and enzyme hydrolysis was compared. The study of cellulase biosynthesis resulted in the conclusion that exo-and endo-glucanases are coinduced while cellobiase is synthesized independent of the other two enzymes.

  8. Integrated chemical and multi-scale structural analyses for the processes of acid pretreatment and enzymatic hydrolysis of corn stover.

    Chen, Longjian; Li, Junbao; Lu, Minsheng; Guo, Xiaomiao; Zhang, Haiyan; Han, Lujia

    2016-05-01

    Corn stover was pretreated with acid under moderate conditions (1.5%, w/w, 121°C, 60min), and kinetic enzymolysis experiments were performed on the pretreated substrate using a mixture of Celluclast 1.5L (20FPU/g dry substrate) and Novozyme 188 (40CBU/g dry substrate). Integrated chemical and multi-scale structural methods were then used to characterize both processes. Chemical analysis showed that acid pretreatment removed considerable hemicellulose (from 19.7% in native substrate to 9.28% in acid-pretreated substrate) and achieved a reasonably high conversion efficiency (58.63% of glucose yield) in the subsequent enzymatic hydrolysis. Multi-scale structural analysis indicated that acid pretreatment caused structural changes via cleaving acetyl linkages, solubilizing hemicellulose, relocating cell wall surfaces and enlarging substrate porosity (pore volume increased from 0.0067cm(3)/g in native substrate to 0.019cm(3)/g in acid-pretreated substrate), thereby improving the polysaccharide digestibility. PMID:26876990

  9. Effect of surfactant on hydrolysis products accumulation and short-chain fatty acids (SCFA) production during mesophilic and thermophilic fermentation of waste activated sludge: kinetic studies.

    Zhang, Peng; Chen, Yinguang; Zhou, Qi

    2010-09-01

    In the presence of surfactant sodium dodecylbenzene sulfonate (SDBS) the hydrolysis products accumulation and the short-chain fatty acids (SCFA) production during waste activated sludge fermentation under mesophilic and thermophilic conditions was compared with that at room temperature. In order to understand the mechanism of significant amounts of mesophilic and thermophilic hydrolysis products and SCFA observed in the presence of surfactant, the kinetic models at different SDBS dosages were developed. It was found that SDBS increased the mesophilic and thermophilic hydrolysis rate significantly, and the maximum specific utilization of hydrolysis products increased at low SDBS and decreased at high one. However, the observed maximum specific utilization of SCFA decreased seriously with SDBS increase. In the presence of SDBS the decay rate of acidogenic bacteria not only was lower than that in the absence of SDBS but decreased with the increase of SDBS under either mesophilic or thermophilic conditions. PMID:20409704

  10. An integrated process for the production of platform chemicals and diesel miscible fuels by acid-catalyzed hydrolysis and downstream upgrading of the acid hydrolysis residues with thermal and catalytic pyrolysis.

    Girisuta, Buana; Kalogiannis, Konstantinos G; Dussan, Karla; Leahy, James J; Hayes, Michael H B; Stefanidis, Stylianos D; Michailof, Chrysa M; Lappas, Angelos A

    2012-12-01

    This study evaluates an integrated process for the production of platform chemicals and diesel miscible biofuels. An energy crop (Miscanthus) was treated hydrothermally to produce levulinic acid (LA). Temperatures ranging between 150 and 200 °C, sulfuric acid concentrations 1-5 wt.% and treatment times 1-12 h were applied to give different combined severity factors. Temperatures of 175 and 200 °C and acid concentration of 5 wt.% were found to be necessary to achieve good yield (17 wt.%) and selectivities of LA while treatment time did not have an effect. The acid hydrolysis residues were characterized for their elemental, cellulose, hemicellulose and lignin contents, and then tested in a small-scale pyrolyzer using silica sand and a commercial ZSM-5 catalyst. Milder pretreatment yielded more oil (43 wt.%) and oil O(2) (37%) while harsher pretreatment and catalysis led to more coke production (up to 58 wt.%), less oil (12 wt.%) and less oil O(2) (18 wt.%). PMID:23073094

  11. Acid hydrolysis and molecular density of phytoglycogen and liver glycogen helps understand the bonding in glycogen α (composite particles.

    Prudence O Powell

    Full Text Available Phytoglycogen (from certain mutant plants and animal glycogen are highly branched glucose polymers with similarities in structural features and molecular size range. Both appear to form composite α particles from smaller β particles. The molecular size distribution of liver glycogen is bimodal, with distinct α and β components, while that of phytoglycogen is monomodal. This study aims to enhance our understanding of the nature of the link between liver-glycogen β particles resulting in the formation of large α particles. It examines the time evolution of the size distribution of these molecules during acid hydrolysis, and the size dependence of the molecular density of both glucans. The monomodal distribution of phytoglycogen decreases uniformly in time with hydrolysis, while with glycogen, the large particles degrade significantly more quickly. The size dependence of the molecular density shows qualitatively different shapes for these two types of molecules. The data, combined with a quantitative model for the evolution of the distribution during degradation, suggest that the bonding between β into α particles is different between phytoglycogen and liver glycogen, with the formation of a glycosidic linkage for phytoglycogen and a covalent or strong non-covalent linkage, most probably involving a protein, for glycogen as most likely. This finding is of importance for diabetes, where α-particle structure is impaired.

  12. Kinetic characterization for hemicellulose hydrolysis of corn stover in a dilute acid cycle spray flow-through reactor at moderate conditions

    The kinetic characterization of hemicellulose hydrolysis of corn stover was investigated using a new reactor of dilute acid cycle spray flow-through (DCF) pretreatment. The primary purpose was to obtain kinetic data for hemicellulose hydrolysis with sulfuric acid concentrations (10-30 kg m-3) at relatively low temperatures (90-100 oC). A simplified kinetic model was used to describe its performance at moderate conditions. The results indicate that the rates of xylose formation and degradation are sensitive to flow rate, temperature and acid concentration. Moreover, the kinetic data of hemicellulose hydrolysis fit a first-order reaction model and the experimental data with actual acid concentration after accounting for the neutralization effect of the substrates at different temperatures. Over 90% of the xylose monomer yield and below 5.5% of degradation product (furfural) yield were observed in this reactor. Kinetic constants for hemicellulose hydrolysis models were analyzed by an Arrhenius-type equation, and the activation energy of xylose formation were 111.6 kJ mol-1, and 95.7 kJ mol-1 for xylose degradation, respectively. -- Highlights: → Investigating a novel pretreatment reactor of dilute acid cycle spray flow-through. → Xylose yield is sensitive to flow rate, temperature and acid concentration. → Obtaining relatively higher xylose monomer yield and lower fermentation inhibitor. → Lumping hemicellulose and xylan oligmers together in the model is a valid way. → The kinetic model as a guide for reactor design, and operation strategy optimization.

  13. Comparative analysis of the effect of pretreating aspen wood with aqueous and aqueous-organic solutions of sulfuric and nitric acid on its reactivity during enzymatic hydrolysis

    Dotsenko, Gleb; Osipov, D. O.; Zorov, I. N.;

    2016-01-01

    The effect of aspen wood pretreatment methods with the use of both aqueous solutions of sulfuric and nitric acids and aqueous-organic solutions (ethanol, butanol) of sulfuric acid (organosolv) on the limiting degree of conversion of this type of raw material into simple sugars during enzymatic...... hydrolysis are compared. The effects of temperature, acid concentration, composition of organic phase (for sulfuric acid), and pressure (for nitric acid) on the effectiveness of pretreatment were analyzed. It is shown that the use of organosolv with 0.5% sulfuric acid allows us to increase the reactivity of...

  14. 基于部分酸水解-亲水作用色谱-质谱的黄芪多糖结构表征%Structural characterization of Astragalus polysaccharides using partial acid hydrolysis-hydrophilic interaction liquid chromatography-mass spectrometry

    梁图; 傅青; 辛华夏; 李芳冰; 金郁; 梁鑫淼

    2014-01-01

    来自中药的水溶性多糖具有广谱治疗和低毒性特点,是天然药物及保健品研发中的重要组成部分。针对中药多糖结构复杂、难以表征的问题,本文以中药黄芪中的多糖为研究对象,采用“自下而上”法完成对黄芪多糖的表征。首先使用部分酸水解方法水解黄芪多糖,分别考察了水解时间、酸浓度和温度的影响。在适宜条件(4 h、1.5 mol/L三氟乙酸、80℃)下,黄芪多糖被水解为特征性的寡糖片段。接下来,采用亲水作用色谱与质谱联用对黄芪多糖部分酸水解产物进行分离和结构表征。结果表明,提取得到的黄芪多糖主要为1→4连接线性葡聚糖,水解得到聚合度4~11的葡寡糖。本研究对其他中药多糖的表征具有一定的示范作用。%Water-soluble polysaccharides from traditional Chinese medicine(TCM)have prop-erties of broad-spectrum treatment and low toxicity,making them as important components in natural medicines and health products. In order to solve the problem of polysaccharides charac-terization caused by their complex structures,a“bottom-up”approach was developed to com-plete the characterization of polysaccharides from Astragalus. Firstly,Astragalus pieces were extracted with hot water and then were precipitated by ethanol to obtain Astragalus polysaccha-rides. Secondly,a partial acid hydrolysis method was carried out and the effects of time,acid concentration and temperature on hydrolysis were investigated. The degree of hydrolysis increased along with the increase of hydrolysis time and acid concentration. The temperature played a great role in the hydrolysis process. No hydrolysis of the polysaccharides occurred at low temperature,while the polysaccharides were almost hydrolyzed to monosaccharide at high temperature. Under the optimum hydrolysis conditions(4 h,1. 5 mol/L trifluoroacetic acid, and 80 ℃),Astragalus polysaccharides were hydrolyzed to

  15. Analysis of saccharification in Brachypodium distachyon stems under mild conditions of hydrolysis

    Statham Emily R

    2008-10-01

    Full Text Available Abstract Background Brachypodium distachyon constitutes an excellent model species for grasses. It is a small, easily propagated, temperate grass with a rapid life cycle and a small genome. It is a self-fertile plant that can be transformed with high efficiency using Agrobacteria and callus derived from immature embryos. In addition, considerable genetic and genomic resources are becoming available for this species in the form of mapping populations, large expressed sequence tag collections, T-DNA insertion lines and, in the near future, the complete genome sequence. The development of Brachypodium as a model species is of particular value in the areas of cell wall and biomass research, where differences between dicots and grasses are greatest. Here we explore the effect of mild conditions of pretreatment and hydrolysis in Brachypodium stem segments as a contribution for the establishment of sensitive screening of the saccharification properties in different genetic materials. Results The non-cellulosic monosaccharide composition of Brachypodium is closely related to grasses of agricultural importance and significantly different from the dicot model Arabidopsis thaliana. Diluted acid pretreatment of stem segments produced significant release of sugars and negatively affected the amount of sugars obtained by enzymatic hydrolysis. Monosaccharide and oligosaccharide analysis showed that the hemicellulose fraction is the main target of the enzymatic activity under the modest hydrolytic conditions used in our assays. Scanning electron microscopy analysis of the treated materials showed progressive exposure of fibrils in the stem segments. Conclusion Results presented here indicate that under mild conditions cellulose and hemicellulose are hydrolysed to differing extents, with hemicellulose hydrolysis predominating. We anticipate that the sub-optimal conditions for hydrolysis identified here will provide a sensitive assay to detect variations in

  16. New steroidal sapogenins from the acid hydrolysis product of the whole glycoside mixture of Welsh onion seeds

    Wei Lai; Ying Bo Yang; Xia Li; Lian Na Sun; Zhi Jun Wu; Wan Sheng Chen

    2012-01-01

    Two new steroidal sapogenins (1,2) along with five known steroidal sapogenins were isolated from the acid hydrolysis product of the whole glycoside mixture of Welsh onion (Allium fistulosum L.) seeds.Based on comprehensive spectroscopic analyses,including 2D NMR spectroscopy and mass spectrometry,their structures were elucidated as (25R)-19-norspirosta-1,3,5 (10)-triene-4-methyl-2-ol (1),(25R)-spirost-1,4-diene-3-one-2,6-diol (2),(25R)-spirost-1,4-diene-3-one-2-ol (3),(25R)-spirost-4-ene-3-one-2-ol (4),yuccagenin (5),gitogenin (6) and tigogenin (7).

  17. Influence of temperature, time, liquid/solid ratio and sulfuric acid concentration on the hydrolysis of palm empty fruit bunches.

    Ferrer, Ana; Requejo, Ana; Rodríguez, Alejandro; Jiménez, Luis

    2013-02-01

    The influence of temperature (150-190 °C), time (0-20 min), liquid/solid ratio (6-8) and sulfuric acid concentration (0.1-0.5%), on the hydrolysis of palm empty fruit bunches (EFBs) was studied and the liquid and solid fractions were analyzed. Polynomial models were found to reproduce the experimental results with errors less than 15% in most of the cases (except for xylose concentration). Operating conditions of 190 °C for 15 min at a liquid/solid ratio of 6 and a sulfuric acid concentration of 0.1% resulted in the production of 3.12, 4.0, 2.35 and 2.28 g/L of glucose, xylose, arabinose and acetic acid, respectively, starting with 1000 g of EFBs. The yield was 67.96%. Soda-anthraquinone, ethanol and ethanolamine pulping of the solid fraction provided pulps with brightness values (63.24%, 28.78%, 48.76%), but with poor resistance properties (6.57-8.54 Nm/g for tensile index, 0.38-0.44 k N/g for burst index and 0.96-1.02 mN m2/g for tear index). Therefore it is advisable to use the pulps for speciality papers or for bioethanol-production. PMID:23266852

  18. Revisiting the Brønsted acid catalysed hydrolysis kinetics of polymeric carbohydrates in ionic liquids by in situ ATR-FTIR spectroscopy

    Kunov-Kruse, Andreas Jonas; Riisager, Anders; Shunmugavel, Saravanamurugan;

    2013-01-01

    A new versatile method to measure rates and determine activation energies for the Brønsted acid catalysed hydrolysis of cellulose and cellobiose (and other polymeric carbohydrates) in ionic liquids is demonstrated by following the C–O stretching band of the glycoside bond with in situ ATR-FTIR. A...

  19. Effect of low severity dilute-acid pretreatment of barley straw and decreased enzyme loading hydrolysis on the production of fermentable substrates and the release of inhibitory compounds

    Panagiotopoulos, I.A.; Lignos, G.D.; Bakker, R.R.C.; Koukios, E.G.

    2012-01-01

    The objective of this work was to investigate the feasibility of combining low severity dilute-acid pretreatment of barley straw and decreased enzyme loading hydrolysis for the high production of fermentable substrates and the low release of inhibitory compounds. For most of the pretreatments at 160

  20. Amino Acids Production from Fish Proteins Hydrolysis in Subcritical Water%近临界水中水解鱼蛋白制备氨基酸

    朱宪; 朱超; 赵亮; 程洪斌

    2008-01-01

    The hydrolysis technology and reaction kinetics for amino acids production from fish proteins in subcritical water reactor without catalysts were investigated in a reactor with volume of 400ml under the conditions of reaction temperature from 180-320℃, pressure from 5-26MPa, and time from 5-60min. The quality and quantity of amino acids in hydrolysate were determined by bioLiquid chromatography, and 17 kinds of amino acids were obtained. For the important 8 amino acids, the experiments were conducted to examine the effects of reaction temperature, pressure and time on amino acids yield. The optimum conditions for high yield are obtained from the experimental results. It is found that the nitrogen and carbon dioxide atmosphere should be used for leucine, isoleucine and histidine production while the air atmosphere might be used for other amino acids. The reaction time of 30min and the experimental temperature of 220℃, 240℃ and 260℃ were adopted for reaction kinetic research. The total yield of amino acids versus reaction time have been examined experimentally. According to these experimental data and under the condition of water excess, the macroscopic reaction kinetic equation of fish proteins hydrolysis was obtained with the hydrolysis reaction order of 1.615 and the rate constants being 0.0017, 0.0045 and 0.0097 at 220℃, 240℃ and 260℃ respectively. The activation energy is 145.1kJ·mol-1.

  1. Hydrolysis of Pentosan for Furfural Preparing Using Sulfuric Acid Catalyst to Improve Diesel Engine Fuel Quality

    The investigation on furfural preparation from peanut shell using sulfuric acid catalyst has been done. Furfural is an organic solvent used in industry especially petroleum industry. The purpose of this investigation is to know the effects of sulfuric acid concentration and solvent feed ratio towards furfural resulted and the reaction kinetics. The experiment was performed in the batch reactor. The result of this investigation showed that the process optimum condition was reached at sulfuric acid concentration of 7% and the solvent feed ratio of 12.5. The result at the optimum condition above was 5.97% of furfural. The relation between percentage of furfural resulted (Y) and sulfuric acid concentration (X) is Y = 0.893 X1.7023 . e-0.2554X with average deviation of 5.880 %. The relation between percentage of furfural resulted (Y) and solvent feed ratio (X) is Y = -53.0411 + 9.4137 X - 0.3780 X2 with average deviation 5.154 %. The relation between reaction rate constant (Y) and sulfuric acid concentration (X) is Y = 3.1916 . 10-3 + 8.2432 . 10-3 X - 5.2324 . 10-4 X2 with average deviation 8.024 %. (author)

  2. Distribution and Variation of Ribonucleic Acid (RNA) and Protein and Its Hydrolysis Products in Lake Sediments

    梁小兵; 万国江; 黄荣贵

    2002-01-01

    Protein and RNA in lake sediments tend to be decomposed progressively with time and sedimentation depth. Their concentrations tend to decrease starting from the sedimentation depth of 17 cm and that of 19 cm, respectively. However, the products of their decomposition-amino acids and nucleotides show different rules of variation. At the depth from 27 cm to 30 cm the amino acids are most abundant in the pore waters of lake sediments. Such variation tendency seems to be related to the extent to which microbes utilize amino acids and nucleotides. Due to polymerization in the geological processes and the adsorption of protein on minerals and organic polymers, below the sedimentation depth of 17 cm there is still a certain amount of protein in the sediments. With the time passing by, protein has been well preserved in various sediment layers, indicating that its decomposition is relatively limited. The peak values of protein content in the sediments of the two lakes are produced in the surface layers at the depth of 10 cm, implicating that the surface sediments are favorable to the release of protein.The contents of amino acids in the pore waters of lake sediments are closely related to the activities of microbes. Below the depth of 27 cm, the amino acids are significantly accumulated in Lake Aha sediments, probably indicating the weakening of microbial activities.

  3. Acid Pre hydrolysis of the Lignocellulose biomass from thistle Onopordum nervosum Boiss; Prehidrolisis acida de la Biomasa Lignocelulosica del Cardo Onopordum nervosum Boiss

    Suarez Contreras, C.; Paz Saa, D.; Diaz Palma, A.

    1983-07-01

    The acid pre hydrolysis of the lignocellulose biomass from thistle O. nervosum has been conducted to determine the conditions for maximum yield of pentoses with minimum yield of hexoses. Variables studied were acid concentration (H{sub 2}SO{sub 4}, 1 , 3, 4 and 5%) , temperature (1000 and 120 degree centigree) time, solid to liquid ratio and degree of fineness of thistle (1 to 65 mesh). (Author) 15 refs.

  4. Hydrolysis of Selected Tropical Plant Wastes Catalyzed by a Magnetic Carbonaceous Acid with Microwave

    Tong-Chao Su; Zhen Fang; Fan Zhang; Jia Luo; Xing-Kang Li

    2015-01-01

    In this study, magnetic carbonaceous acids were synthesized by pyrolysis of the homogeneous mixtures of glucose and magnetic Fe3O4 nanoparticles, and subsequent sulfonation. The synthesis conditions were optimized to obtain a catalyst with both high acid density (0.75 mmol g−1) and strong magnetism [magnetic saturation, Ms = 19.5 Am2 kg−1]. The screened catalyst (C-SO3H/Fe3O4) was used to hydrolyze ball-milled cellulose in a microwave reactor with total reducing sugar (TRS) yield of 25.3% und...

  5. Hydrolysis mechanisms for the organopalladium complex [Pd(CNN)P(OMe)3]BF4 in sulfuric acid.

    García, Begoña; Hoyuelos, Francisco J; Ibeas, Saturnino; Muñoz, María S; Peñacoba, Indalecio; Leal, José M

    2009-08-13

    The acid-catalyzed hydrolysis of the organopalladium complex [Pd(CNN)P(OMe)3]BF4 species was monitored spectrophotometrically at different sulfuric acid concentrations (3.9 and 11.0 M) in 10% v:v ethanol-water over the 25-45 degrees C temperature range and in 30% and 50% (v/v) ethanol-water at 25 degrees C. Two acidity regions (I and II) could be differentiated. In each of the two regions the kinetic data pairs yielded two different rate constants, k(1obs) and k(2obs), the former being faster. These constants were fitted by an Excess Acidity analysis to different hydrolyses mechanisms: A-1, A-2, and A-SE2. In region I ([H2SO4] 7.0 M), a switchover was observed from an A-1 mechanism (k(0,A1) = 1.3 x 10(-4) s(-1)) to an A-2 mechanism (k(0,A2) = 3.6 x 10(-3) M(-1) s(-1)). The temperature effect on the rate constants in 10% (v/v) ethanol-water yielded positive DeltaH and negative DeltaS values, except for the A-1 mechanism, where DeltaS adopted positive values throughout. The solvent permittivity effect, epsilonr, revealed that k(1obs)(av) and k(0,A2) dropped with a fall in epsilonr, whereas the k(0,ASE2) value remained unaffected. The set of results deduced is in line with the schemes put forward. PMID:19621916

  6. Effect of gamma Irradiation on the acidic hydrolysis of free-hemi cellulose thistle; Efecto de la irradiacion gamma en la hidrolisis acida de cardo exento de pentosas

    Suarez, C.; Paz, M. D.; Diaz, A.

    1983-07-01

    The effect of gamma-irradiation on the subsequent acidic hydrolysis of free-hemi cellulose Onopordum Nervosum Boiss thistle Ls determined. Its shown the influence of gamma-irradiation on the yield of sugar obtained flora the batch wise hydrol isis of the call ulose (1% H{sub 2}SO{sub 4} and 180 degree centigree at increasing doses). At all irradiation levels studied, the rate of hydrolysis of thistle samples was higher than the rate of hydrolysis of the cellulose from paper treated similarly. The maximum over-all yield of sugar in the irradiated lignocellulose material was about 66o at 100 MRad, less than two times the yield obtainable from the control. The corresponding yield from papel was 53%, 2'3 times that of the control. Irradiation under 1% H{sub 2}SO{sub 4} doesn't enhance the yield anyway. (Author) 21 refs.

  7. Influence of solid loading on D-xylose production through dilute sulphuric acid hydrolysis of olive stones

    Cuevas, M.

    2015-09-01

    Full Text Available The selective hydrolysis of hemicellulose from olive stones was attempted in order to achieve a maximum D-xylose yield. For this aim, batch hydrolysis was conducted under different operating conditions of temperature, acid concentration and solid loading. Firstly, distilled water, sulphuric acid and nitric acid were assessed as hydrolytic agents at different temperatures (200, 205, 210 and 220 °C and at a fixed acid concentration (0.025 M. Sulphuric acid and 200 °C were selected for the subsequent dilute acid hydrolysis optimization based on the obtained D-xylose yields. The combined influence of solid loading (from 29.3 to 170.7 g olive stones into 300 mL acid solution and sulphuric acid concentration (0.006–0.034 M on the release of D-xylose was then estimated by response surface methodology. According to a statistical analysis, both parameters had significant interaction effects on D-xylose production. The results illustrated that the higher the solid loading, the higher the required acid concentration. The decrease in the solid/liquid ratio in the reactor had a positive effect on D-xylose extraction and on the amount of acid used. The optimum solid loading and sulphuric acid concentration were determined to be 50 g (solid/liquid ratio 1/6 and 0.016 M, respectively. Under these conditions, the predicted D-xylose yield (expressed as g of sugar per 100 g of dry matter fed was 20.4 (87.2% of maximum attainable.Se ha desarrollado una hidrólisis selectiva de la fracción hemicelulósica del hueso de aceituna con el fin de obtener el máximo rendimiento de D-xilosa. Para ello las hidrólisis se llevaron a cabo en un reactor discontinuo a distintas condiciones de temperatura, concentración de ácido y carga de sólidos. En primer lugar se evaluó la capacidad hidrolítica del agua destilada y de los ácidos nítrico y sulfúrico a distintas temperaturas (200, 205, 210 y 220°C manteniendo fija la concentración de ácido (0,025 M. A partir de

  8. 18O isotope effect in 13C nuclear magnetic resonance spectroscopy. Part 9. Hydrolysis of benzyl phosphate by phosphatase enzymes and in acidic aqueous solutions

    The 18O isotope-induced shifts in 13C and 31P nuclear magnetic resonance (NMR) spectroscopy were used to establish the position of bond cleavage in the phosphatase-catalyzed and acid-catalyzed hydrolysis reactions of benzyl phosphate. The application of the 18O-isotope effect in NMR spectroscopy affords a continuous, nondestructive assay method for following the kinetics and position of bond cleavage in the hydrolytic process. The technique provides advantages over most discontinuous methods in which the reaction components must be isolated and converted to volatile derivatives prior to analysis. In the present study, [α-13C,ester-18O]benzyl phosphate and [ester-18O]benzyl phosphate were synthesized for use in enzymatic and nonenzymatic studies. Hydrolysis reactions catalyzed by the alkaline phosphatase from E. coli and by the acid phosphatases isolated from human prostate and human liver were all accompanied by cleavage of the substrate phosphorus-oxygen bond consistent with previously postulated mechanisms involving covalent phosphoenzyme intermediates. An extensive study of the acid-catalyzed hydrolysis of benzyl phosphate at 750C revealed that the site of bond cleavage is dependent on pH. At pH less than or equal to 1.3, the hydrolysis proceeds with C-O bond cleavage; at 1.3 2H]Benzyl phosphate was also synthesized. Hydrolysis of this chiral benzyl derivative demonstrated that the acid-catalyzed C-O bond scission of benzyl phosphate proceeds by an A-1 (S/sub N/1) mechanism with 70% racemization and 30% inversion at carbon. 37 references, 4 figures, 2 tables

  9. 酸法水解绿潮藻生物质及发酵制乙醇的效果%Effect of preparing alcohol with green tide algae biomass by acid hydrolysis

    张维特; 时旭; 欧杰; 李柏林; 杨建强; 胡翔; 房建孟; 何培民

    2011-01-01

    以2008年我国沿海暴发的绿潮藻浒苔生物质为原材料,分析了海藻中的营养成分,探讨了温度、时间、酸度、料水比等因子对浒苔生物质硫酸水解的影响,通过4因素5水平正交实验,结果显示温度影响极为显著,其次为酸度、时间、料水比,最终确定水解优化组合条件为:温度90℃、时间70 min、硫酸浓度5.0%、料水比4.5%.通过液相色谱法检测水解液中的单糖成分,结果表明浒苔水解液中含有葡萄糖、木糖和鼠李糖,其摩尔比为1.71:1.00:1.29.同时确定了5种酵母菌(酵母菌1770、1766、啤酒酵母S1、酿酒酵母S2、酵母菌IwSc1)的生长曲线,在其进入稳定期时进行厌氧发酵,发酵完成后用气相色谱法检测最终产物中的乙醇含量,结果显示酿酒酵母S2效果最好,其乙醇含量为2.1 g/L,乙醇得率为26%,发酵液中葡萄糖浓度由18.26 g/L降至2.38 g/L,利用率达87%.S1、S2、IwSc1主要利用葡萄糖,1770、1766可以利用葡萄糖和木糖.%In summer of 2008, green tides broke out in south Yellow Sea. First, the nutrition of floating algae was analyzed and then the algae were treated by sulphuric acid for getting reducing sugar. The effects of temperature( ℃ ), treating time( min), sulphuric acid concentration ( % ), ratio of mass weight( % ) on the biomass hydrolyzation were studied and the hydrolysis conditions were optimized by orthogonal analysis. The results showed that optimum conditions for floating Ulva prolifera biomass hydrolysis by sulphuric acid were 90 ℃ of treating temperature, 70 min of treating time, 5% of sulphuric acid concentration, 4.5% of ratio of the mass weight. Liquid chromatography analysis showed that the molar ratio of monosaccharides in hydrolyzate were glucose 1.71: xylose 1.00: rhamnose 1.29. Growth curves of five yeasts ( IwSc1, S1, S2,1770,1766 )were drawn in order to ferment the liquid at stationary phase. The results showed that S2 was the best for

  10. PREPARATION OF XYLOSE AND KRAFT PULP FROM POPLAR BASED ON FORMIC/ACETIC ACID /WATER SYSTEM HYDROLYSIS

    Junping Zhuang

    2009-08-01

    Full Text Available A formic/acetic acid/water system was used in the ratios of 30:60:10, 20:60:20, and 30:50:20 separately for efficient hydrolysis and bioconversion of poplar chips, under the solid/liquid ratio of 1:12(g/ml, at 105 oC for 30, 45, 60, 75, and 90 min, respectively. The highest yield of 69.89% was at a formic/acetic acid /water ratio of 30:50:20(v/v/v, with solid/liquid in the ratio of 1:12(g/ml at 105 oC for 90min. Lower kappa number and similar yield were achieved when hydrolytic residual woodchips were used for kraft pulping with over 2% Na2O and temperature 5 °C lower compared to untreated chips. Pulps from prehydrolysis-treated chips were easy to beat. But the tensile index, tear index, and burst index of the handsheets obtained from pulp with lowest kappa number from prehydrolysis-treated poplar chips were lower than those of the pulp from the untreated chips. Considerable xylose could be obtained from the prehydrolysis stage following kraft pulping under the same conditions for prehydrolysis-treated chips and untreated chips. However, by building on the mature kraft pulping and xylitol processes, large amounts of xylose from the hemicellulose were obtained in prehydrolysis, allowing production of high-valued products via biorefinery pathways. An economical balance of chemical dosage, energy consumption, pulp properties, and xylose value for prehydrolysis with organic acid should be reached with further investigation.

  11. Depolymerization of coal by O2 oxidation followed by acid hydrolysis; Sanso sanka-kasui bunkai ni yoru sekitan no teionkai jugo

    Aizawa, S.; Hayashi, J.; Kumagai, H.; Chiba, T. [Hokkaido University, Sapporo (Japan). Center for Advanced Research of Energy Technology; Morooka, S. [Kyushu University, Fukuoka (Japan). Faculty of Engineering

    1996-10-28

    With an objective to elucidate characteristics of oxygen addition to coal, and characteristics of solvent extraction by means of depolymerization, experiments were performed on oxygen oxidation and acid hydrolysis of brown coals. Coals used for the experiments are Morwell (MW), Yallourn (YL) , South Banko (SB) and Wyoming (WY) coals. Test samples were suspended in weak alkaline aqueous solution, and then oxygen was blown into them with pressure kept at atmospheric pressure. After a lapse of a predetermined time, the samples were cooled, and made as acidic as pH 1.3 in hydrochloric acid, followed by acid hydrolysis. Oxygen consumption increased with the reaction time, and with the MW coal, one mol oxygen reacted to 11 mols of coal. Spectral analysis on the YL and WY coal experiments revealed that aliphatic carbon combined with aromatic carbon or ether group has turned to peroxide, whose C-C or C-O bond was broken down as a result of acid hydrolysis of the peroxide, producing oxygen containing compounds. As a result of the depolymerization, the rate of extraction by using DMF, DMSO and methanol/THF mixed solvent increased to 90% or higher. Proportion of bond and cutting-off affects largely collapse of the cross-link structure. The carbon conversion to volatiles was at most 4%. 1 ref., 10 figs.

  12. Microwave-Assisted Method for Simultaneous Hydrolysis and Extraction for Preparation of Geniposidic Acid from Eucommia ulmoides Bark Using Basic Imidazolide Ionic Liquid

    Lili Li

    2016-01-01

    Full Text Available In order to hydrolyze geniposide and extract geniposidic acid, a novel microwave irradiation heating method for simultaneous hydrolysis and extraction for preparation of geniposidic acid from Eucommia ulmoides bark using basic imidazolide ionic liquid was developed in this work. Basic ionic liquid paired by imidazolide anion and 1-hexyl-3-methylimidazolium cation ([C6mim]Im was used as a dual hydrolysis catalyst and extraction solvent in the proposed approach. The optimal concentration of [C6mim]Im was 0.4 mol/L. And the independent parameters optimized by Box-Behnken design (BBD based on single-factor tests were as follows: microwave irradiation time of 20 min at power of 415 W and liquid-solid ratio of 15 mL/g. Yield of geniposidic acid was increased to 3.41±0.17 μmol/g. DM130 macroporous resin, after reaction, was selected to separate geniposidic acid from hydrolysate. The plant materials with different treatment were analyzed by scanning electron microscopy (SEM and thermogravimetric analysis (TG. The analysis of SEM and TG further indicated that IMSHE is an efficient preparation method for geniposidic acid. It is reasonable to assume that the method and the dual hydrolysis catalyst and extraction solvent would offer an alternative for the preparation of some other kinds of bioactive substances from plant materials.

  13. Quantification of monosaccharides through multiple-reaction monitoring liquid chromatography/mass spectrometry using an aminopropyl column.

    Hammad, Loubna A; Derryberry, Dakota Z; Jmeian, Yazen R; Mechref, Yehia

    2010-06-15

    A simple, sensitive, and reproducible quantitative liquid chromatography/tandem mass spectrometry (LC/MS/MS) method was designed for the simultaneous quantification of monosaccharides derived from glycoprotein and blood serum using a multiple-reaction monitoring (MRM) approach. Sialic acids and neutral monosaccharides were efficiently separated using an amino-bonded silica phase column. Neutral monosaccharide molecules were detected as their aldol acetate anion adducts [M + CH(3)CO(2)](-) using electrospray ionization in negative ion MRM mode, while sialic acids were detected as deprotonated ions [M-H](-). The new method did not require a reduction step, and exhibited very high sensitivity to carbohydrates with limits of detection of 1 pg for the sugars studied. The linearity of the described approach spanned over three orders of magnitude (pg to ng). The method was validated for monosaccharides originating from N-linked glycans attached to glycoproteins and glycoproteins found in human blood serum. The method effectively quantified monosaccharides originating from as little as 1 microg of glycoprotein and 5 microL of blood serum. The method was robust, reproducible, and highly sensitive. It did not require reduction, derivatization or postcolumn addition of reagents. PMID:20486252

  14. Effects of formic acid hydrolysis on the quantitative analysis of radiation-induced DNA base damage products assayed by gas chromatography/mass spectrometry

    Gas chromatography/mass spectrometry (GC/ MS-SIM) is an excellent technique for performing both qualitative and quantitative analysis of DNA base damage products that are formed by exposure to ionizing radiation or by the interaction of intracellular DNA with activated oxygen species. This technique commonly uses a hot formic acid hydrolysis step to degrade the DNA to individual free bases. However, due to the harsh nature of this degradation procedure, the quantitation of DNA base damage products may be adversely affected. Consequently, we examined the effects of various formic acid hydrolysis procedures on the quantitation of a number of DNA base damage products and identified several factors that can influence this quantitation. These factors included (1) the inherent acid stabilities of both the lesions and the internal standards; (2) the hydrolysis temperature; (3) the source and grade of the formic acid; and (4) the sample mass during hydrolysis. Our data also suggested that the N, O-bis (trimethylsilyl)trifluoroacetamide (BSTFA) derivatization efficiency can be adversely affected, presumably by trace contaminants either in the formic acid or from the acid-activated surface of the glass derivatization vials. Where adverse effects were noted, modifications were explored in an attempt to improve the quantitation of these DNA lesions. Although experimental steps could be taken to minimize the influence of these factors on the quantitation of some base damage products, no single procedure solved the quantitation problem for all base lesions. However, a significant improvement in the quantitation was achieved if the relative molecular response factor (RMRF) values for these lesions were generated with authentic DNA base damage products that had been treated exactly like the experimental samples. (orig.)

  15. Enhancing bio-butanol production from biomass of Chlorella vulgaris JSC-6 with sequential alkali pretreatment and acid hydrolysis.

    Wang, Yue; Guo, Wanqian; Cheng, Chieh-Lun; Ho, Shih-Hsin; Chang, Jo-Shu; Ren, Nanqi

    2016-01-01

    This study presents a successful butanol production method using alkali and acid pretreated biomass of Chlorella vulgaris JSC-6. The butanol concentration, yield, and productivity were 13.1g/L, 0.58mol/mol sugar, 0.66g/L/h, respectively. Nearly 2.93L/L of biohydrogen was produced during the acidogenesis phase in ABE fermentation. The hydrogen yield and productivity were 0.39mol/mol sugar and 104.2g/L/h respectively. In addition, the high glucose consumption efficiency (97.5%) suggests that the hydrolysate pretreated with NaOH (1%) followed by H2SO4 (3%) did not contain inhibitors to the fermentation. It was also discovered that an excess amount of nitrogen sources arising from hydrolysis of highly concentrated microalgal biomass negatively affected the butanol production. This work demonstrates the technical feasibility of producing butanol from sustainable third-generation feedstock (i.e., microalgal biomass). PMID:26528906

  16. Evaluation of xylitol production using corncob hemicellulosic hydrolysate by combining tetrabutylammonium hydroxide extraction with dilute acid hydrolysis.

    Jia, Honghua; Shao, Tingting; Zhong, Chao; Li, Hengxiang; Jiang, Min; Zhou, Hua; Wei, Ping

    2016-10-20

    In this paper, we produced hemicellulosic hydrolysate from corncob by tetrabutylammonium hydroxide (TBAH) extraction and dilute acid hydrolysis combined, further evaluating the feasibility of the resultant corncob hemicellulosic hydrolysate used in xylitol production by Candida tropicalis. Optimized conditions for corncob hemicellulose extraction by TBAH was obtained via response surface methodology: time of 90min, temperature of 60°C, liquid/solid ratio of 12 (v/w), and TBAH concentration of 55%, resulting in a hemicellulose extraction of 80.07% under these conditions. The FT-IR spectrum of the extracted corncob hemicellulose is consistent with that of birchwood hemicellulose and exhibits specific absorbance of hemicelluloses at 1380, 1168, 1050, and 900cm(-1). In addition, we found that C. tropicalis can ferment the resulting corncob hemicellulosic hydrolysate with pH adjustment and activated charcoal treatment leading to a high xylitol yield and productivity of 0.77g/g and 2.45g/(Lh), respectively. PMID:27474613

  17. Deuterium isotope effects on acid ionization and transition metal hydrolysis at reactor conditions by Raman spectroscopy

    This paper reports the preliminary measurements from an experimental study to measure the small differences between light (H2O) and heavy (D2O) water under reactor operating conditions (250-300 oC, 10 MPa), using Raman spectroscopy. The deuterium isotope effect δpK = pKD2O - pKH2O, for sodium bisulphate NaDSO4 and phosphoric acid D3PO4, has now been determined at temperatures of 25 oC and 80 oC by measuring the isotropic Raman spectra at different concentrations. The results for the pK and ΔpK at 25 oC agree with the literature, confirming the reliability of the method. High temperature cells have been constructed. (author)

  18. In Candida parapsilosis the ATC1 gene encodes for an acid trehalase involved in trehalose hydrolysis, stress resistance and virulence.

    Ruth Sánchez-Fresneda

    Full Text Available An ORF named CPAR2-208980 on contig 005809 was identified by screening a Candida parapsilosis genome data base. Its 67% identity with the acid trehalase sequence from C. albicans (ATC1 led us to designate it CpATC1. Homozygous mutants that lack acid trehalase activity were constructed by gene disruption at the two CpATC1 chromosomal alleles. Phenotypic characterization showed that atc1Δ null cells were unable to grow on exogenous trehalose as carbon source, and also displayed higher resistance to environmental challenges, such as saline exposure (1.2 M NaCl, heat shock (42°C and both mild and severe oxidative stress (5 and 50 mM H2O2. Significant amounts of intracellular trehalose were specifically stored in response to the thermal upshift in both wild type and mutant strains. Analysis of their antioxidant activities revealed that catalase was only triggered in response to heat shock in atc1Δ cells, whereas glutathione reductase was activated upon mild oxidative stress in wild type and reintegrant strains, and in response to the whole set of stress treatments in the homozygous mutant. Furthermore, yeast cells with double CpATC1 deletion were significantly attenuated in non-mammalian infection models, suggesting that CpATC1 is required for the pathobiology of the fungus. Our results demonstrate the involvement of CpAtc1 protein in the physiological hydrolysis of external trehalose in C. parapsilosis, where it also plays a major role in stress resistance and virulence.

  19. Validated Method for the Characterization and Quantification of Extractable and Nonextractable Ellagitannins after Acid Hydrolysis in Pomegranate Fruits, Juices, and Extracts.

    García-Villalba, Rocío; Espín, Juan Carlos; Aaby, Kjersti; Alasalvar, Cesarettin; Heinonen, Marina; Jacobs, Griet; Voorspoels, Stefan; Koivumäki, Tuuli; Kroon, Paul A; Pelvan, Ebru; Saha, Shikha; Tomás-Barberán, Francisco A

    2015-07-29

    Pomegranates are one of the main highly valuable sources of ellagitannins. Despite the potential health benefits of these compounds, reliable data on their content in pomegranates and derived extracts and food products is lacking, as it is usually underestimated due to their complexity, diversity, and lack of commercially available standards. This study describes a new method for the analysis of the extractable and nonextractable ellagitannins based on the quantification of the acid hydrolysis products that include ellagic acid, gallic acid, sanguisorbic acid dilactone, valoneic acid dilactone, and gallagic acid dilactone in pomegranate samples. The study also shows the occurrence of ellagitannin C-glycosides in pomegranates. The method was optimized using a pomegranate peel extract. To quantify nonextractable ellagitannins, freeze-dried pomegranate fruit samples were directly hydrolyzed with 4 M HCl in water at 90 °C for 24 h followed by extraction of the pellet with dimethyl sulfoxide/methanol (50:50, v/v). The method was validated and reproducibility was assessed by means of an interlaboratory trial, showing high reproducibility across six laboratories with relative standard deviations below 15%. Their applicability was demonstrated in several pomegranate extracts, different parts of pomegranate fruit (husk, peels, and mesocarp), and commercial juices. A large variability has been found in the ellagitannin content (150-750 mg of hydrolysis products/g) and type (gallagic acid/ellagic acid ratios between 4 and 0.15) of the 11 pomegranate extracts studied. PMID:26158321

  20. Gas-phase hydrolysis of triplet SO2: A possible direct route to atmospheric acid formation.

    Donaldson, D James; Kroll, Jay A; Vaida, Veronica

    2016-01-01

    Sulfur chemistry is of great interest to the atmospheric chemistry of several planets. In the presence of water, oxidized sulfur can lead to new particle formation, influencing climate in significant ways. Observations of sulfur compounds in planetary atmospheres when compared with model results suggest that there are missing chemical mechanisms. Here we propose a novel mechanism for the formation of sulfurous acid, which may act as a seed for new particle formation. In this proposed mechanism, the lowest triplet state of SO2 ((3)B1), which may be accessed by near-UV solar excitation of SO2 to its excited (1)B1 state followed by rapid intersystem crossing, reacts directly with water to form H2SO3 in the gas phase. For ground state SO2, this reaction is endothermic and has a very high activation barrier; our quantum chemical calculations point to a facile reaction being possible in the triplet state of SO2. This hygroscopic H2SO3 molecule may act as a condensation nucleus for water, giving rise to facile new particle formation (NPF). PMID:27417675

  1. Biological Activities of Hominis Placenta Herbal Acupuncture prepared by Hydrochloric Acid Hydrolysis

    Geun-young Seo

    2010-06-01

    Full Text Available Reactive Oxygen Species(ROS are continuously produced at a high rate as a by-product of aerobic metabolism. Since tissue damage by free radical increases with age, the reactive oxygen species(ROS such as hydrogen peroxide(H2O2, nitric oxide(NO. Several lines of evidence provided that ROS appears to cause to develop aging-related various diseases such as cancer, arthritis, cardiovascular disease. In this study, we have conducted to investigate the biological activities of Hominis Placenta Herbal Acupuncture by measuring total polyphenol content, DPPH radical scavenging, ABTS radical scavenging, Superoxide dismutase(SOD-like activity, Nitrite scavenging ability in vitro. The total polyphenol contents of Hominis Placenta Herbal Acupuncture was 24.6㎖/㎖. Elctron donation ability on DPPH was 49.4%. The 2,2'-azinobis-3-ehtlbezothiazoline-6-sulfonic acid radical decolorization (ABTS was 50.01%, similar to the DPPH free radical scavenging. The superoxide dismutase (SOD-like activities of hominis placenta herbal acupuncture was 50.876%. The nitrite scavenging abilities at pH 1.5, pH 3.0, pH 6.0 were 52.8%, 29.4%, 15.4%, respectively; these abilities decreased as pH increased. We conclude that Hominis Placenta Herbal Acupuncture may be useful as potential sources of antioxidant.

  2. Evaluation of jumbo squid (Dosidicus gigas) byproduct hydrolysates obtained by acid-enzymatic hydrolysis and by autohydrolysis in practical diets for Pacific white shrimp (Litopenaeus vannamei)

    Mayra Lizett González-Félix; Martin Perez-Velazquez; Josafat Marina Ezquerra-Brauer; Lorena Bringas-Alvarado; Anabel Sánchez-Sánchez; Wilfrido Torres-Arreola

    2014-01-01

    The marine bioprocessing industry offers great potential to utilize byproducts for fish meal replacement in aquafeeds. Jumbo squid is an important fishery commodity in Mexico, but only the mantle is marketed. Head, fins, guts and tentacles are discarded in spite of being protein-rich byproducts. This study evaluated the use of two jumbo squid byproduct hydrolysates obtained by acid-enzymatic hydrolysis (AEH) and by autohydrolysis (AH) as ingredients in practical diets for shrimp. The hydrolys...

  3. Summary Report on Gamma Radiolysis of TBP/n-dodecane in the Presence of Nitric Acid Using the Radiolysis/Hydrolysis Test Loop

    Design and installation has been completed for a state-of-the-art radiolysis/hydrolysis test loop system. The system is used to evaluate the effects of gamma radiolysis and acid hydrolysis on the stability and performance of solvent extraction process solvents. The test loop is comprised of two main sections; the solvent irradiation and hydrolysis loop and the solvent reconditioning loop. In the solvent irradiation and hydrolysis loop, aqueous and organic phases are mixed and circulated through a gamma irradiator until the desired absorbed dose is achieved. Irradiation of the mixed phases is more representative of actual conditions in a solvent extraction process. Additionally, the contact of the organic phase with the aqueous phase will subject the solvent components to hydrolysis. This hydrolysis can be accelerated by controlling the system at an elevated temperature. At defined intervals, the organic from the irradiation/hydrolysis loop will be transferred to the solvent reconditioning loop where the solvent is contacted with scrub, strip, and solvent wash solutions which simulate process flowsheet conditions. These two processes are repeated until the total desired dose is achieved. Since all viable solvent extraction components in an advanced fuel cycle must exhibit high radiolytic and hydrolytic stability, this test loop is not limited to any one solvent system but is applicable to all systems of interest. Also, the test loop is not limited to testing of process flowsheets. It is also a valuable tool in support of fundamental research on newly identified extractants/modifiers and the impact of gamma radiation on their stability in a dynamic environment. The investigation of the radiolysis of a TBP/n-dodecane process solvent in contact with aqueous nitric acid has been performed. These studies were intended to confirm/optimize the operability of the test loop system. Additionally, these data are directly applicable to numerous other solvent extraction

  4. Summary Report on Gamma Radiolysis of TBP/n-dodecane in the Presence of Nitric Acid Using the Radiolysis/Hydrolysis Test Loop

    Dean R. Peterman; Bruce J. Mincher; Catherine L. Riddle; Richard D. Tillotson

    2010-08-01

    Design and installation has been completed for a state-of-the-art radiolysis/hydrolysis test loop system. The system is used to evaluate the effects of gamma radiolysis and acid hydrolysis on the stability and performance of solvent extraction process solvents. The test loop is comprised of two main sections; the solvent irradiation and hydrolysis loop and the solvent reconditioning loop. In the solvent irradiation and hydrolysis loop, aqueous and organic phases are mixed and circulated through a gamma irradiator until the desired absorbed dose is achieved. Irradiation of the mixed phases is more representative of actual conditions in a solvent extraction process. Additionally, the contact of the organic phase with the aqueous phase will subject the solvent components to hydrolysis. This hydrolysis can be accelerated by controlling the system at an elevated temperature. At defined intervals, the organic from the irradiation/hydrolysis loop will be transferred to the solvent reconditioning loop where the solvent is contacted with scrub, strip, and solvent wash solutions which simulate process flowsheet conditions. These two processes are repeated until the total desired dose is achieved. Since all viable solvent extraction components in an advanced fuel cycle must exhibit high radiolytic and hydrolytic stability, this test loop is not limited to any one solvent system but is applicable to all systems of interest. Also, the test loop is not limited to testing of process flowsheets. It is also a valuable tool in support of fundamental research on newly identified extractants/modifiers and the impact of gamma radiation on their stability in a dynamic environment. The investigation of the radiolysis of a TBP/n-dodecane process solvent in contact with aqueous nitric acid has been performed. These studies were intended to confirm/optimize the operability of the test loop system. Additionally, these data are directly applicable to numerous other solvent extraction

  5. Gas chromatographic determination of polysaccharide gums in foods after hydrolysis and derivatization.

    Lawrence, J F; Iyengar, J R

    1985-12-20

    A gas chromatographic method was evaluated for the determination of food grade gums in dairy products, salad dressings and meat sauces. The gums studied were tragacanth, karaya, ghatti, carob, guar, arabic and xanthan gum. The extraction method included removal of fat followed by starch degradation then precipitation of protein. The isolated gums were hydrolysed with trifluoroacetic acid and the resulting neutral monosaccharides converted to their aldonitrile acetate derivatives for determination by gas chromatography. Recoveries from thirteen different commodities averaged 85%. However, the recovery of guar gum from ice cream and cold pack cheese was 42 and 50%, respectively. In a comparison of enzyme hydrolysis and iodine complexation for the removal of starch the former was simpler and provided cleaner extracts than the iodine treatment. Both gave similar results. PMID:4093481

  6. Kinetics of enzymatic hydrolysis of methyl ricinoleate

    Neeharika, T. S.V.R.; Lokesh, P.; Prasanna Rani, K. N.; Prathap Kumar, T.; Prasad, R. B.N.

    2015-01-01

    Ricinoleic acid is an unsaturated hydroxy fatty acid that naturally occurs in castor oil in proportions of up to 85–90%. Ricinoleic acid is a potential raw material and finds several applications in coatings, lubricant formulations and pharmaceutical areas. Enzymatic hydrolysis of castor oil is preferred over conventional hydrolysis for the preparation of ricinoleic acid to avoid estolide formation. A kinetics analysis of the enzymatic hydrolysis of Methyl Ricinoleate in the presence of Candi...

  7. Subcritical Water Extraction of Monosaccharides from Oil Palm Fronds Hemicelluloses

    Oil palm plantations in Malaysia generate more than 36 million tones of pruned and felled oil palm fronds (OPF) and are generally considered as waste. The composition of monosaccharide in oil palm frond can be extracted using hydrothermal treatment for useful applications. The objectives of this study were to quantify the yield of monosaccharides at various reaction conditions; temperature 170 to 200 degree Celsius, pressure from 500 psi to 800 psi, reaction time from 5 to 15 min using subcritical water extraction and to determine the composition of oil palm frond hemicelluloses at optimum condition. The monosaccharides composition of oil palm frond hemicelluloses were analysed using High Performance Liquid Chromatography (HPLC). The highest yield of monosaccharides can be extracted from OPF at temperature of 190 degree Celsius, pressure of 600 psi and 10 min of contact time which is xylose the most abundant composition (11.79 %) followed with arabinose (2.82 %), glucose (0.61 %) and mannose (0.66 %). (author)

  8. Centrifugal partition chromatography in a biorefinery context: Separation of monosaccharides from hydrolysed sugar beet pulp.

    Ward, David P; Cárdenas-Fernández, Max; Hewitson, Peter; Ignatova, Svetlana; Lye, Gary J

    2015-09-11

    A critical step in the bioprocessing of sustainable biomass feedstocks, such as sugar beet pulp (SBP), is the isolation of the component sugars from the hydrolysed polysaccharides. This facilitates their subsequent conversion into higher value chemicals and pharmaceutical intermediates. Separation methodologies such as centrifugal partition chromatography (CPC) offer an alternative to traditional resin-based chromatographic techniques for multicomponent sugar separations. Highly polar two-phase systems containing ethanol and aqueous ammonium sulphate are examined here for the separation of monosaccharides present in hydrolysed SBP pectin: l-rhamnose, l-arabinose, d-galactose and d-galacturonic acid. Dimethyl sulfoxide (DMSO) was selected as an effective phase system modifier improving monosaccharide separation. The best phase system identified was ethanol:DMSO:aqueous ammonium sulphate (300gL(-1)) (0.8:0.1:1.8, v:v:v) which enabled separation of the SBP monosaccharides by CPC (200mL column) in ascending mode (upper phase as mobile phase) with a mobile phase flow rate of 8mLmin(-1). A mixture containing all four monosaccharides (1.08g total sugars) in the proportions found in hydrolysed SBP was separated into three main fractions; a pure l-rhamnose fraction (>90%), a mixed l-arabinose/d-galactose fraction and a pure d-galacturonic acid fraction (>90%). The separation took less than 2h demonstrating that CPC is a promising technique for the separation of these sugars with potential for application within an integrated, whole crop biorefinery. PMID:26278358

  9. Study of the Soret Effect in Monosaccharide Solutions

    Blanco, P.; Wiegand, S.

    2010-01-01

    We investigated the thermal diffusion behavior of aqueous solutions of monosaccharides with the infrared thermal diffusion forced Rayleigh scattering (IR-TDFRS) setup. As monosaccharides, we studied the three aldohexoses glucose, galactose, and mannose and the two ketohexoses sorbose and fructose. All sugars have the same molecular weight, but their structures differ as well as some physical properties such as viscosity, density, thermal expansion coefficient, and optical rotation. Additional...

  10. Purification of the lysosomal sialic acid transporter. Functional characteristics of a monocarboxylate transporter

    A.C. Havelaar (Adrie); G.M.S. Mancini (Grazia); C.E.M.T. Beerens (Cecile); R.M. Souren; F.W. Verheijen (Frans)

    1998-01-01

    textabstractSialic acid and glucuronic acid are monocarboxylated monosaccharides, which are normally present in sugar side chains of glycoproteins, glycolipids, and glycosaminoglycans. After degradation of these compounds in lysosomes, the free monosaccharides are relea

  11. Hydrolysis of palm oil catalyzed by acid%棕榈油的酸催化水解工艺研究

    张玲玲; 王晖

    2015-01-01

    以棕榈油为原料进行常压酸催化水解工艺研究。考察了反应时间、反应温度、催化剂用量、油水质量比及乳化剂用量对棕榈油水解反应的影响,得出棕榈油一次酸催化水解的最佳反应条件:反应时间7 h,反应温度100℃,催化剂浓硫酸用量7.5%,油水质量比1∶1,乳化剂磺酸用量0.5%;在最佳反应条件下棕榈油水解产物酸值(KOH)为192.77 mg/g,水解率达到91.96%。并研究出一套循环水解的工艺流程,实现油脂水解产物的循环利用,提高了水相中甘油的含量。%The hydrolysis of palm oil catalyzed by acid was studied. The effects of reaction time,reaction temperature,catalyst dosage,mass ratio of oil to water and emulsifier dosage on the hydrolysis of palm oil were investigated. The optimal reaction conditions of palm oil hydrolysis were obtained as follows:reaction time 7 h,reaction temperature 100℃,mass ratio of oil to water 1∶1,dosage of sulfonic acid used as emul-sifier 0. 5% and catalyst( concentrated sulfonic acid) dosage 7. 5%. Under the optimal reaction condi-tions,the acid value of the hydrolysates was up to 192. 77 mgKOH/g and the hydrolysis rate of palm oil was 91. 96%. A circulated hydrolysis process was designed, then the recycling of hydrolysates was real-ized,and the content of glycerin in the aqueous phase increased.

  12. A Newly Isolated Penicillium oxalicum 16 Cellulase with High Efficient Synergism and High Tolerance of Monosaccharide.

    Zhao, Xi-Hua; Wang, Wei; Tong, Bin; Zhang, Su-Ping; Wei, Dong-Zhi

    2016-01-01

    Compared to Trichoderma reesei RUT-C30 cellulase (Trcel), Penicillium oxalicum 16 cellulase (P16cel) from the fermentation supernatant produced a 2-fold higher glucose yield when degrading microcrystalline cellulose (MCC), possessed a 10-fold higher β-glucosidase (BGL) activity, but obtained somewhat lower other cellulase component activities. The optimal temperature and pH of β-1,4-endoglucanase, cellobiohydrolase, and filter paperase from P16cel were 50-60 °C and 4-5, respectively, but those of BGL reached 70 °C and 5. The cellulase cocktail of P16cel and Trcel had a high synergism when solubilizing MCC and generated 1.7-fold and 6.2-fold higher glucose yields than P16cel and Trcel at the same filter paperase loading, respectively. Additional low concentration of fructose enhanced the glucose yield during enzymatic hydrolysis of MCC; however, additional high concentration of monosaccharide (especially glucose) reduced cellulase activities and gave a stronger monosaccharide inhibition on Trcel. These results indicate that P16cel is a more excellent cellulase than Trcel. PMID:26410224

  13. Determination of Monosaccharide Constituents in Lycium Barbarum Polysaccharide Using Capillary Ion Chromatography with Pulsed Amperometric Detection%毛细管型离子色谱-脉冲安培法检测枸杞多糖的单糖组成

    李静; 李仁勇; 梁立娜

    2012-01-01

    采用ICS-5000毛细管离子色谱仪对枸杞多糖中的10种单糖进行了分离测定.优化了前处理过程中影响多糖水解的酸种类、酸浓度、水解温度和时间等参数,优化条件为使用2 mol/L三氟乙酸溶液在100℃下水解120min,在该条件下,果糖回收率约为50%,其余单糖回收率在84%~104%之间.采用新型淋洗液自动发生装置电解产生淋洗液,Capillary CarborPac PA20色谱柱分离,毛细管安培池检测,10种单糖成分标准曲线线性关系良好,相关系数均大于99.9%;检出限在2.5~75 μg/L之间,为枸杞多糖中单糖组分测定提供了新的可行方法.%A method for the determination of ten kinds of monosaccharide in Lycium barbarum polysaccharide was established using ICS-5000 Capillary IC system. In the pretreatment process, the type and concentration of acid, the hydrolysis temperature and lasting time were selected or optimized. The optimized hydrolysis condition was 100℃ lasting 120 min with 2 mol/L trifluoroacetic acid solution. Under this condition the recovery rate of fructose was about 50%. Recovery rate of the rest monosaccharide was 84% to 104%. In the experiment, new type of Eluent Generator, Capillary CarborPac PA20 column, and improved capillary amperometric detection cell were used. The calibration curves of ten kinds of monosaccharide showed good linearity with correlation coefficient above 0. 999. The LOD is between 2. 5 to 75 μg/L. It is suitable for the determination of monosaccharide constituents in Lycium barbarum polysaccharide.

  14. Aggregates-Based Boronlectins with Pyrene as Fluorophore: Multichannel Discriminative Sensing of Monosaccharides and Their Applications.

    Zhang, Xiao-Tai; Wang, Shu; Xing, Guo-Wen

    2016-05-18

    Four-channel fluorescence assay toward six monosaccharides was achieved by employing two novel pyrene-functionalized boronlectins with flexible diboronic acid as receptors. The effects of pH values and aging time on the sensor properties were thoroughly evaluated by UV-vis, fluorescence spectroscopy and dynamic light scattering. We find that the fluorescence relative ratios were highly correlated with analyte concentrations at μM level. The flexibility of the receptors was perceived as an indispensable factor to produce diverse fluorescence signals toward different monosaccharides. Most importantly, integration of four fluorescence channels derived from the two sensors enables an excellent discrimination for all tested monosaccharides at a certain concentration or a concentration range via linear discriminant analysis (LDA). It is proposed that the multiple flexible linkers in the boronlectins could increase their self-adaptive capacity for different analytes, and facilitate the formation of stable boronlectin-sugar aggregate assemblies. In addition, practical sensing of glucose in the simulative blood and urine was illustrated to be feasible in the presence of interferences at physiological concentrations. PMID:27110925

  15. Hydrolysis of Cellulose by a Mesoporous Carbon-Fe2(SO4)3/γ-Fe2O3 Nanoparticle-Based Solid Acid Catalyst

    Yamaguchi, Daizo; Watanabe, Koki; Fukumi, Shinya

    2016-02-01

    Carbon-based solid acid catalysts have shown significant potential in a wide range of applications, and they have been successfully synthesized using simple processes. Magnetically separable mesoporous carbon composites also have enormous potential, especially in separation and adsorption technology. However, existing techniques have been unable to produce a magnetically separable mesoporous solid acid catalyst because no suitable precursors have been identified. Herein we describe a magnetically separable, mesoporous solid acid catalyst synthesized from a newly developed mesoporous carbon-γ-Fe2O3 nanoparticle composite. This material exhibits an equivalent acid density and catalytic activity in the hydrolysis of microcrystalline cellulose, to that of the cellulose-derived conventional catalyst. Since it is magnetically separable, this material can be readily recovered and reused, potentially reducing the environmental impact of industrial processes to which it is applied.

  16. Effects of organic acids on rice straw on supercritical hydrolysis%超临界下有机酸对稻秆水解糖化的影响

    李星纬; 巩桂芬; 李晓东

    2012-01-01

    With the organic acids ( formic acid, acetic acid, and propionic acid) as the catalyst, hydrolysis saccharification of rice straw in the batch reactor was investigated under the condition of the super- and sub-critical water. The reaction temperature, reaction time and solid-to-liquid ratio for reduction sugar yield were studied. Results showed that organic acid was helpful to the hydrolysis saccharification of straw. Reducing sugar yield could increase when adding organic acid. This trend was most evident when adding formic acid. With the extension of reaction time, reducing sugar yield could gradually decreased. In the appropriate range, reducing sugar production was much higher with the increasing of the solid-liquid ratio. The best conditions on straw hydrolysis saccharification in supercritical water from the experiment were as follows; formic acid concentration 3%, solid-to-liquid ratio 4:60, temperature 410 ℃ , and the reaction time 5 min. Under the conditions, the reducing sugar production reached the highest, 6. 65 g/L.%采用间歇式反应器在超临界条件下,以有机酸(甲酸、乙酸和丙酸)为催化剂对稻秆进行水解糖化研究,重点考察反应温度、反应时间、固液比对还原糖产率的影响.实验表明:有机酸的加入有利于稻秆的水解糖化,稻秆水解速率和还原糖产量都有所提高,这种趋势在加入甲酸时最为明显;随着反应时间的延长,还原糖产量会逐渐减少;适当提高固液比有助于增加还原糖产量.稻秆超临界水解糖化的最佳条件:甲酸体积分数3%、固液比4∶60(g/mL)、反应温度410℃、反应时间5 min,在此条件下,还原糖产量最高,达6.65 g/L.

  17. Use of surfactants in enzymatic hydrolysis of rice straw and lactic acid production from rice straw by simultaneous saccharification and fermentation

    Shichun Peng

    2007-01-01

    Full Text Available Rice straw (RS is one of the most abundant lignocellulosic waste by-products worldwide and provides an alternative substrate to produce useful chemicals such as bioethanol and lactic acid. However, higher enzyme loadings are needed to obtain a higher product yield, which makes the large-scale utilization economically difficult. The presence of non-ionic surfactants and poly(ethylene glycol (PEG during the enzymatic hydrolysis of lignocellulosics has been found to increase the conversion of cellulose into fermentable sugars. We have found that adding 0.2g g-1 substrate of polyoxyethylene(20 sorbitan monooleate (PSM or high-mass PEG increased the sugar yield by 22% and 12%, respectively, when enzyme loading was at 10FPU g-1 for 24h. PSM behaved better than PEG when different substrate concentrations, temperatures, and enzyme loadings were investigated. PSM provides an opportunity to reduce enzyme dosage while still keeping the same extent of hydrolysis. We also investigated the effect of PSM on the simultaneous saccharification and fermentation of pretreated RS to lactic acid. Results showed that addition of 0.7g L-1 PSM improved the lactic acid production by 24% compared to the reference without PSM addition at 72h.

  18. Super acid catalysed sequential hydrolysis/cycloisomerization of -(acetylenic)benzamides under microwave condition: Synthesis, antinociceptive and antiinflammatory activity of substituted isocoumarins

    Chandrasekaran Praveen; P Dheenkumar; P T Perumal

    2013-01-01

    Synthesis of isocoumarins and related compounds via triflic acid promoted hydrolysis/cyclization sequence of 2-(alkynyl)benzamides under microwave condition was achieved. The substrate scope of the reaction was broad to include not only aromatic but also polyaromatic and heteroaromatic motifs, thus highlighting the significance of this methodology. One-pot operation, short reaction time, good chemical yields and excellent regioselectivity are the advantages of this protocol. All the synthesized compounds were evaluated for their antinociceptive and antiinflammatory activities using in vivo rodent models.

  19. Isolation of pectin from pumpkin (Cucurbita moschata, L.) by acid hydrolysis;Isolamento de pectina de abobora (Cucurbita moschata, L.) por hidrolise acida

    Souza, Jose R.R.; Ricardo, Nagila M.P.S.; Paula, Regina C.M. de; Feitosa, Judith P.A., E-mail: judith@dqoi.ufc.b [Universidade Federal do Ceara (UFC), Fortaleza, CE (Brazil). Dept. de Quimica Organica e Inorganica. Lab. de Polimeros; Brito, Edy S. [EMBRAPA Agroindustria Tropical, Fortaleza, CE (Brazil)

    2009-07-01

    Pumpkin (Cucurbita moschata, L.) constitutes an excellent source of carotenoids, precursors of vitamin A. Besides, it also that constitutes also a great natural source of low-cost pectin. Pectin is a heterogeneous complex polysaccharide found in the primary cell wall of most plants and its effect on health is receiving increasing interest from the scientific community. In this work, high-methoxy pectin was obtained from pumpkin (Cucurbita moschata, L.) through the acid hydrolysis methodology. The pectin obtained was characterized by FTIR, NMR {sup 1}H, GPC and rheology. (author)

  20. High conversion of sugarcane bagasse into monosaccharides based on sodium hydroxide pretreatment at low water consumption and wastewater generation.

    Wang, Wen; Wang, Qiong; Tan, Xuesong; Qi, Wei; Yu, Qiang; Zhou, Guixiong; Zhuang, Xinshu; Yuan, Zhenhong

    2016-10-01

    The generation of a great quantity of black liquor (BL) and waste wash water (WWW) has been key problems of the alkaline pretreatment. This work tried to build a sustainable way to recycle the BL for pretreating sugarcane bagasse (SCB) and the WWW for washing the residual solid (RS) of alkali-treated SCB which would be subsequently hydrolysed and fermented. The enzymatic hydrolysis efficiency of the washed RS decreased with the recycling times of BL and WWW increasing. Tween80 at the loading of 0.25% (V/V) could notably improve the enzymatic hydrolysis and had no negative impact on the downstream fermentation. Compared with the non-recycling and BL recycling ways based on alkaline pretreatment, the BL-WWW recycling way could not only maintain high conversion of carbohydrate into monosaccharides and save alkali amount of 45.5%, but also save more than 80% water and generate less than 15% waste water. PMID:27474958

  1. Speciation analysis of seleno-amino acids in human serum: comparison of methods with and without protein hydrolysis

    Full text: This study presents the development of a reference method based on (reverse phase) HPLC-ICPMS for the determination of selenomethionine (SeMet) in human serum, following the enzymatic hydrolysis of selenoalbumin (SeAlb), a seleno-containing protein. Quantification of SeMet was carried out by species-specific isotope dilution (SSID); the assessment of the uncertainty budget and the steps contributing significantly to the overall uncertainty are addressed. The SSID HPLC-ICPMS procedure for the determination of SeMet in human serum was compared with a method relying on speciation analysis of intact selenoproteins (i.e. without hydrolysis), namely glutathione peroxidase, selenoprotein P and SeAlb, by means of a affinity-HPLC coupled to ICPMS. (author)

  2. Enzymatic hydrolysis of corn bran arabinoxylan

    Agger, Jane

    This thesis concerns enzymatic hydrolysis of corn bran arabinoxylan. The work has focused on understanding the composition and structure of corn bran with specific interest in arabinoxylan with the main purpose of targeting enzymatic hydrolysis for increased yields. Corn bran has been used as a...... model substrate because it represents a readily available agroindustrial side product with upgrading potentials. Corn bran originates from the wet-milling process in corn starch processing, is the outmost layers of the corn kernel and is particularly rich in pentose monosaccharides comprising the major...... components of arabinoxylan. Corn bran is one of the most recalcitrant cereal byproducts with arabinoxylans of particular heterogeneous nature. It is also rich in feruloyl derived substitutions, which are responsible for extensive cross-linking between arabinoxylan molecules and thereby participate in a...

  3. Pretreatment by NaOH swelling and then HCl regeneration to enhance the acid hydrolysis of cellulose to glucose.

    Sun, Binzhe; Peng, Gege; Duan, Lian; Xu, Aihua; Li, Xiaoxia

    2015-11-01

    A simple pretreatment method, NaOH swelling at a low temperature and then HCl regeneration, was developed for depolymerization of cellulose to glucose. Cellulose was transformed into amorphous hydrogel during the treatment; and due to the easy diffusion of H(+) and Cl(-) ions into the cellulose hydrogel network as well as the strong ability of Cl(-) to disrupt the massive hydrogen bond, the hydrolysis rate was greatly enhanced. The method is effective for α-cellulose, microcrystalline cellulose, filter paper, ramie fiber and absorbent cotton. Even at a high α-cellulose concentration of 50g/L, 29.1% yield of glucose was still obtained within 10min at 160°C under microwave irradiation, where up to 16.2g/L of glucose solution was given. The influence of NaOH concentration, HCl concentration, hydrolysis temperature and time on the hydrolysis rate was investigated. The structure of cellulose hydrogel was also studied to confirm the reaction mechanism. PMID:26280097

  4. Chemometrics-assisted Spectrofluorimetric Determination of Two Co-administered Drugs of Major Interaction, Methotrexate and Aspirin, in Human Urine Following Acid-induced Hydrolysis.

    Maher, Hadir M; Ragab, Marwa A A; El-Kimary, Eman I

    2015-01-01

    Methotrexate (MTX) is widely used to treat rheumatoid arthritis (RA), mostly along with non-steroidal anti-inflammatory drugs (NSAIDs), the most common of which is aspirin or acetyl salicylic acid (ASA). Since NSAIDs impair MTX clearance and increase its toxicity, it was necessary to develop a simple and reliable method for the monitoring of MTX levels in urine samples, when coadministered with ASA. The method was based on the spectrofluorimetric measurement of the acid-induced hydrolysis product of MTX, 4-amino-4-deoxy-10-methylpteroic acid (AMP), along with the strongly fluorescent salicylic acid (SA), a product of acid-induced hydrolysis of aspirin and its metabolites in urine. The overlapping emission spectra were resolved using the derivative method (D method). In addition, the corresponding derivative emission spectra were convoluted using discrete Fourier functions, 8-points sin xi polynomials, (D/FF method) for better elimination of interferences. Validation of the developed methods was carried out according to the ICH guidelines. Moreover, the data obtained using derivative and convoluted derivative spectra were treated using the non-parametric Theil's method (NP), compared with the least-squares parametric regression method (LSP). The results treated with Theil's method were more accurate and precise compared with LSP since the former is less affected by the outliers. This work offers the potential of both derivative and convolution using discrete Fourier functions in addition to the effectiveness of using the NP regression analysis of data. The high sensitivity obtained by the proposed methods was promising for measuring low concentration levels of the two drugs in urine samples. These methods were efficiently used to measure the drugs in human urine samples following their co-administration. PMID:26234512

  5. Acid Hydrolysis of Wheat Gluten Induces Formation of New Epitopes but Does Not Enhance Sensitizing Capacity by the Oral Route: A Study in “Gluten Free” Brown Norway Rats

    Kroghsbo, Stine; Andersen, Nanna Birch; Rasmussen, Tina Frid; Jacobsen, Susanne; Madsen, Charlotte Bernhard

    2014-01-01

    BackgroundAcid hydrolyzed wheat proteins (HWPs) are used in the food and cosmetic industry as emulsifiers. Cases of severe food allergic reactions caused by HWPs have been reported. Recent data suggest that these reactions are caused by HWPs produced by acid hydrolysis.ObjectivesTo examine the sensitizing capacity of gluten proteins per se when altered by acid or enzymatic hydrolysis relative to unmodified gluten in rats naïve to gluten.MethodsHigh IgE-responder Brown Norway (BN) rats bred on...

  6. Evaluation of jumbo squid (Dosidicus gigas byproduct hydrolysates obtained by acid-enzymatic hydrolysis and by autohydrolysis in practical diets for Pacific white shrimp (Litopenaeus vannamei

    Mayra Lizett González-Félix

    2014-09-01

    Full Text Available The marine bioprocessing industry offers great potential to utilize byproducts for fish meal replacement in aquafeeds. Jumbo squid is an important fishery commodity in Mexico, but only the mantle is marketed. Head, fins, guts and tentacles are discarded in spite of being protein-rich byproducts. This study evaluated the use of two jumbo squid byproduct hydrolysates obtained by acid-enzymatic hydrolysis (AEH and by autohydrolysis (AH as ingredients in practical diets for shrimp. The hydrolysates were included at levels of 2.5 and 5.0% of the diet dry weight in four practical diets, including a control diet without hydrolysate. Shrimp growth and survival were not significantly affected by the dietary treatments. Postharvest quality of abdominal muscle was evaluated in terms of proximate composition and sensory evaluation. Significantly higher crude protein was observed in the muscle of shrimp fed the highest hydrolysate levels, AH 5% (204.8 g kg- 1 or AEH 5% (201.3 g kg- 1. Sensory analysis of cooked muscle showed significant differences for all variables evaluated: color, odor, flavor, and firmness. It was concluded that Jumbo squid byproducts can be successfully processed by autohydrolysis or acid-enzymatic hydrolysis, and that up to 5.0% of the hydrolysates can be incorporated into shrimp diets without affecting growth or survival.

  7. EFFECT OF INHIBITORS ON ENZYMATIC HYDROLYSIS AND SIMULTANEOUS SACCHARIFICATION FERMENTATION FOR LACTIC ACID PRODUCTION FROM STEAM EXPLOSION PRETREATED LESPEDEZA STALKS

    Yue Feng; Xiang Qi,; Hong-lei Jian,; Run-cang Sun; Jian-xin Jiang

    2012-01-01

    The effects on both cellulose conversion rate and lactic acid yield were studied by adding inhibitors, including formic acid, acetic acid, furfural, and vanillin into the hydrolysate of steam-pretreated Lespedeza stalks. The results suggest that formic acid has a significant influence on the enzyme activity and poisoned bacterial cells, resulting in the reduction of cellulose conversion rate and lactic acid yield by 21% and 16.4%, respectively. Acetic acid showed a strong inhibition on simult...

  8. HIDROLISIS ENZIMATIK MINYAK IKAN UNTUK PRODUKSI ASAM LEMAK OMEGA-3 MENGGUNAKAN LIPASE DARI Aspergillus niger [Enzymatic Hydrolysis of Fish Oil for Production of Omega-3 Fatty Acids Using Lipase Derived from Aspergillus niger

    Sapta Raharja*

    2011-06-01

    Full Text Available Fish oil is the source of important fatty-acid, especially polyunsaturated fatty acid (PUFA omega-3, such as eicosapentaenoic acid (EPA and docosahexaenoic acid (DHA. Lipase catalysis activity of Aspergillus niger is low when it is used in fish oil hydrolysis. The activity of the lipase can be increased by adding organic solvent such as hexane into the media. This research aimed to determine temperature, pH and amount of water which produce the highest degree of hydrolysis of fish oil in the presence of hexane. Correlation between the highest degree of hydrolysis and the amount of omega-3 fatty acid was also investigated. The variables used in this research were temperatures (25-65 oC, pH (5-9, and water addition (1-5 %v/v. The highest degree of enzymatic hydrolysis of fish oil in the media without hexane was 28.07 % that was reached at 45oC and pH 5. In the presence of hexane, the highest degree of hydrolysis was 75.12 % which was reached at 5% water addition, temperature 45oC, and pH 5. GC-MS analysis showed that omega-3 fatty acid content especially EPA and DHA increased along with increase in the degree of hydrolysis. Concentration of omega-3 fatty acid produced without hexane addition was 18.42 % with EPA amounted to 12,17% and DHA 0,86%. Meanwhile omega-3 fatty acid content in the presence of hexane reached 21.93 % with EPA amounted to 17.75 % and DHA 1.21 %.

  9. Direct conversion of cellulose to glycolic acid with a phosphomolybdic acid catalyst in a water medium

    Zhang, Jizhe

    2012-08-03

    Direct conversion of cellulose to fine chemicals has rarely been achieved. We describe here an eco-benign route for directly converting various cellulose-based biomasses to glycolic acid in a water medium and oxygen atmosphere in which heteromolybdic acids act as multifunctional catalysts to catalyze the hydrolysis of cellulose, the fragmentation of monosaccharides, and the selective oxidation of fragmentation products. With commercial α-cellulose powder as the substrate, the yield of glycolic acid reaches 49.3%. This catalytic system is also effective with raw cellulosic biomass, such as bagasse or hay, as the starting materials, giving rise to remarkable glycolic acid yields of ∼30%. Our heteropoly acid-based catalyst can be recovered in solid form after reaction by distilling out the products and solvent for reuse, and it exhibits consistently high performance in multiple reaction runs. © 2012 American Chemical Society.

  10. Synthesis, Characterization, Antibacterial and Antifungal Evaluation of Novel Monosaccharide Esters

    Yong Deng

    2012-07-01

    Full Text Available A novel series of 3-(2-furylacrylate monosaccharide esters Iaf and menthyloxycarbonyl monosaccharide esters IIaf were designed and synthesized. The chemical structures of the target compounds were confirmed by IR, 1H- and 13C-NMR and ESI-MS, and the target compounds were investigated for their in vitro antibacterial and antifungal activities. The antibacterial screening results showed that the 3-(2-furylacrylate monosaccharide ester derivatives Iaf were either inactive or only weakly active against the three Gram-positive bacterial strains tested, whereas the menthyloxycarbonyl monosaccharide ester derivatives IIaf exhibited higher levels of activity, with compound IIe being especially potent. The results of the antifungal screening revealed that compounds Ib, Ie, IIb and IIc displayed potent in vitro activities, whereas If and IIf showed promising activities against all of the microorganisms tested, with If exhibiting levels of activity deserving of further investigation.

  11. Characteristics of Bone Gelatin Tilapia (Oreochromis niloticus) Processed by Using Hydrolysis With Phosphoric Acid and Papain Enzyme

    Gugun Hidayat; Eko Nurcahya Dewi; Laras Rianingsih

    2016-01-01

    Phosphoric acid and papain enzyme able to hydrolyzing collagen from Tilapia into gelatin . The purpose of this research was to determine the best concentration of phosphoric acid and papain enzyme and to determine the physicochemical characteristic gelatin to from Tilapia fish bone which processed with phosphoric acid and papain enzyme. The first research phase was making bone gelatin tilapia using phosphoric acid at concentration of 4%, 5% and 6%, and the papain enzyme 0.5%, 1% a...

  12. A study of the acid-catalyzed hydrolysis of cellulose dissolved in ionic liquids and the factors influencing the dehydration of glucose and the formation of humins.

    Dee, Sean J; Bell, Alexis T

    2011-08-22

    An investigation was carried out into the hydrolysis of cellulose dissolved in 1-ethyl-3-methylimidazolium chloride ([Emim][Cl]) and 1-butyl-3-methylimidazolium chloride ([Bmim][Cl]) catalyzed by mineral acids. Glucose, cellobiose, and 5-hydroxymethylfurfural (5-HMF) were observed as the primary reaction products. The initial rate of glucose formation was determined to be of first order in the concentrations of dissolved glucan and protons and of zero order in the concentration of water. The absence of a dependence on water concentration suggests that cleavage of the β-1,4-glycosidic linkages near chain ends is irreversible. The apparent activation energy for glucose formation is 96 kJ mol(-1). The absence of oligosaccharides longer than cellobiose suggests that cleavage of interior glycosidic bonds is reversible due to the slow diffusional separation of cleaved chains in the highly viscous glucan/ionic liquid solution. Progressive addition of water during the course of glucan hydrolysis inhibited the rate of glucose dehydration to 5-HMF and the formation of humins. The inhibition of glucose dehydration is attributed to stronger interaction of protons with water than the 2-OH atom of the pyranose ring of glucose, the critical step in the proposed mechanism for the formation of 5-HMF. The reduction in humin formation associated with water addition is ascribed to the lowered concentration of 5-HMF, since the formation of humins is suggested to proceed through the condensation polymerization of 5-HMF with glucose. PMID:21809450

  13. Fermentative l-lactic acid production from pretreated whole slurry of oil palm trunk treated by hydrothermolysis and subsequent enzymatic hydrolysis.

    Eom, In-Yong; Oh, Young-Hoon; Park, Si Jae; Lee, Seung-Hwan; Yu, Ju-Hyun

    2015-06-01

    A simple and cost-effective biochemical conversion process consisting of hydrothermal treatment, enzymatic hydrolysis and fermentation of pretreated whole slurry (PWS) was developed for producing l-lactic acid (L-LA) from oil palm trunk (OPT). When OPT was hydrothermally treated at optimal condition capable of achieving maximum yield of hemicellulosic sugars after enzymatic hydrolysis, the enzymatic digestibility of the PWS afforded a yield of 81.4% of the theoretical glucose yield (TGY). However, glucose yield from washed pretreated solid (WPS) was only 43.5% of TGY. The use of two hydrolysates from PWS and WPS for fermentation by Lactobacillus paracasei engineered to selectively produce L-LA afforded yields of 89.5% and 45.8% of the theoretical LA yield (TLY), respectively. This study confirmed the inevitable extensive sugar loss during washing of pretreated slurry due to loss of soluble starch. Alternatively, the proposed design process is considered suitable for converting OPT to L-LA without such starch loss. PMID:25768416

  14. Enhancement of enzymatic hydrolysis of corn stover by γ-irradiation and combined solvent delignification/acid prehydrolysis

    Two pretreatment schemes were studied for their effect on the enhancement of soluble sugar production from corn stover by enzymatic hydrolysis. In the first scheme, prior to enzymic hydrolysis corn stover which was ground to pass a 1 mm screen was immersed in NaOH solution and exposed to gamma irradiation. The NaOH levels and radiation dosages were varied from 0 to 0.51 gNaOH/g corn stover and from 50 to 150 Mr, respectively. The combined residue and solubles were then hydrolyzed with a commercial cellulase (Onozuka) in 0.05 M citrate buffer at pH 4.6 and 390C for 48 hours. The highest sugar yield of 96% based on the total carbohydrate content of the original sample was obtained at 100 Mr and 0.06 gNaOH/g corn stover. In the second scheme, corn stover which was ground to pass a 0.35 mm screen was delignified with ethanol-water-NaOH. The ethanol-water mixture used contained 3 parts (by volume) of 95% ethanol and 4 g NaOH/L; substrate concentration was 5% (w/v). The delignification was carried out at 1400C for 1 hour. At these conditions, 65% of the lignin was removed while 90% of the carbohydrates remained insoluble. The delignified corn stover with an without treatment using 2% wt.% H2SO4 at 950C and 1 hour was then enzymically hydrolyzed with Novo Cellulclast at pH 4.8 and 500C for up to 48 hours. Factors that affect the overall sugar production are presented and discussed. In addition, the overall sugar yields for the two schemes are compared with other pretreatment schemes reported. (orig.)

  15. Hydrolysis-acidogenesis of food waste in solid-liquid-separating continuous stirred tank reactor (SLS-CSTR) for volatile organic acid production.

    Karthikeyan, Obulisamy Parthiba; Selvam, Ammaiyappan; Wong, Jonathan W C

    2016-01-01

    The use of conventional continuous stirred tank reactor (CSTR) can affect the methane (CH4) recovery in a two-stage anaerobic digestion of food waste (FW) due to carbon short circuiting in the hydrolysis-acidogenesis (Hy-Aci) stage. In this research, we have designed and tested a solid-liquid-separating CSTR (SLS-CSTR) for effective Hy-Aci of FW. The working conditions were pH 6 and 9 (SLS-CSTR-1 and -2, respectively); temperature-37°C; agitation-300rpm; and organic loading rate (OLR)-2gVSL(-1)day(-1). The volatile fatty acids (VFA), enzyme activities and bacterial population (by qPCR) were determined as test parameters. Results showed that the Hy-Aci of FW at pH 9 produced ∼35% excess VFA as compared to that at pH 6, with acetic and butyric acids as major precursors, which correlated with the high enzyme activities and low lactic acid bacteria. The design provided efficient solid-liquid separation there by improved the organic acid yields from FW. PMID:26512860

  16. Chemical recycling of post-consumer PET: structural characterization of terephthalic acid and the effect of Alkaline Hydrolysis at low temperature

    Due to the environmental impact caused by PET packaging disposal, this material recycling has been thoroughly discussed and evaluated. In particular, chemical recycling enables achievement of the monomers that are used in PET resin manufacture: ethylene glycol (EG) and terephthalic acid (PTA). Therefore, studies for this process optimization are important from environmental and economic points of view. The present study investigated certain parameters that influence the depolymerization reaction of PET post-consumer via alkaline hydrolysis in order to obtain PTA. Assays were performed at 70 °C by varying the concentration of sodium hydroxide and the reaction time. The best results were obtained at 10.82 mol L-1 NaOH and 9 h reaction time. Consequently, it was possible to prove this process viability, once analyses by infrared and nuclear magnetic resonance confirmed that PTA was obtained in all reactions performed. (author)

  17. Evaluation of soluble fraction and enzymatic residual fraction of dilute dry acid, ethylenediamine, and steam explosion pretreated corn stover on the enzymatic hydrolysis of cellulose.

    Qin, Lei; Liu, Li; Li, Wen-Chao; Zhu, Jia-Qing; Li, Bing-Zhi; Yuan, Ying-Jin

    2016-06-01

    This study is aimed to examine the inhibition of soluble fraction (SF) and enzymatic residual fraction (ERF) in dry dilute acid (DDA), ethylenediamine (EDA) and steam explosion (SE) pretreated corn stover (CS) on the enzymatic digestibility of cellulose. SF of DDA, EDA and SE pretreated CS has high xylose, soluble lignin and xylo-oligomer content, respectively. SF of EDA pretreated CS leads to the highest inhibition, followed by SE and DDA pretreated CS. Inhibition of ERF of DDA and SE pretreated CS is higher than that of EDA pretreated CS. The inhibition degree (A0/A) of SF is 1.76 and 1.21 times to that of ERF for EDA and SE pretreated CS, respectively. The inhibition degree of ERF is 1.05 times to that of SF in DDA pretreated CS. The quantitative analysis shows that SF of EDA pretreated CS, SF and ERF of SE pretreated CS cause significant inhibition during enzymatic hydrolysis. PMID:26970919

  18. The effect of the H2O/TEOS ratio on the structure of gels derived by the acid catalysed hydrolysis of tetraethoxysilane

    Silica gels were produced by the acid catalysed hydrolysis of tetraethoxysilane (TEOS) using H2O/TEOS ratios from 2 to 50. After heat treatment the structure of the gels was studied using nitrogen adsorption, small angle X-ray scattering (SAXS), transmission electron microscopy (TEM) and bulk density measurements. All the gels possessed microporosity in the region of 30 A or less. For H2O/TEOS = 25 and 50 the matrix density was found to be uniform, but for gels from solutions with H2O/TEOS = 2, 4 and 10, density fluctuations in the matrix were detected from a Porod analysis of the SAXS data. These results indicate that in high water content solutions, rearrangement of the polymeric chains leads to small densified particles, but for lower water content solutions, gelation results from the entanglement of linear chains leaving free volume on a molecular scale between the chains. (Author)

  19. Quantification of organic acids in particulate matter by coupling of thermally assisted hydrolysis and methylation with thermodesorption-gas chromatography-mass spectrometry.

    Beiner, K; Plewka, A; Haferkorn, S; Iinuma, Y; Engewald, W; Herrmann, H

    2009-09-18

    A quantitative method for the determination of organic acids in atmospheric particles is developed. The method couples a derivatisation step (thermally assisted hydrolysis and methylation) and a Curie point pyrolyser as a thermal desorption technique and gas chromatography-mass spectrometry (CPP-GC-MS). Among the reagents tested (tetramethylammonium hydroxide (TMAH), tetramethylammonium acetate (TMAAc) and phenyltrimethylammonium hydroxide (TMPAH)), the best performance was found using TMAAc as a derivatisation reagent for the reaction time of 4s at 510 degrees C as heating temperature. Calibration was performed for a series of fatty acids (FA), dicarboxylic acids (DCA) and terpenoic acids (TA) under these conditions. Coefficients of determination (R(2)) were between 0.94 and 0.98. Limits of detection (LOD) were in the nanogram-range between 0.1 and 3.6 ng. The method is applied on atmospheric particle samples to obtain the quantification reproducibility and quantification limits. Reproducibility was determined in terms of relative standard deviations (RSD) for ambient aerosol samples collected by a high-volume-sampler (HVS, RSD=6-45%, n=10) and a Berner impactor (BI, RSD=5-34%, n=10). Based on 24h sampling time the developed method enables quantification of all three classes of acids for both sampling techniques. Calibration data and presented volume concentrations are compared with literature data. A comparison with an off-line methylation-GC-MS using BF(3) as a derivatisation reagent and capillary electrophoresis coupled mass spectrometry (CE-MS) showed a good agreement. Minimal sample preparation is the main advantage of the developed method. Depending on the sensitivity requirements the present method can be a fast and simple alternative to GC-MS techniques with conventional sample preparation steps for semi-volatile organic acids. PMID:19679312

  20. Monosaccharides in the water of the Gulf of Gdansk

    Waldemar Grzybowski

    2001-06-01

    Full Text Available The concentration of monosaccharides in samples collected in the Gulf of Gdansk area was determined in water filtered through ~0.8 µm pore size filters. Seawater concentrations ranged from about 0.2 to 1.1 mg C dm-3, the highest values being detected at the mouth of the river Vistula. Seasonality was detectable in the data distribution; the majority of autumn values lay within the 0.2–0.4 range while concentrations in the spring samples were higher and the values more widely scattered. Measurements of monosaccharide concentrations at selected points during the whole observation period showed that values increased from spring to autumn as much as 5-fold. Concomitant analyses in Vistula river water yielded concentrations from 0.4 to 1.2 mg C dm-3. These latter values were all higher than those recorded in seawater in the corresponding months.

  1. Galactan synthesis in a single step via oligomerization of monosaccharides

    Marius Dräger

    2014-11-01

    Full Text Available Galactans ranging in length from one to five residues were prepared in a single step by treatment of the glycosyl donor 2,3,4-tri-O-benzoyl-β-D-galactopyranosyl fluoride with lanthanum perchlorate in the presence of an initiator alcohol. The product oligosaccharides were readily chromatographically separable. This oligomerization was used to synthesize a pentagalactan in a single step from monosaccharide building blocks in reasonable overall yields.

  2. Galactan synthesis in a single step via oligomerization of monosaccharides

    Marius Dräger; Amit Basu

    2014-01-01

    Galactans ranging in length from one to five residues were prepared in a single step by treatment of the glycosyl donor 2,3,4-tri-O-benzoyl-β-D-galactopyranosyl fluoride with lanthanum perchlorate in the presence of an initiator alcohol. The product oligosaccharides were readily chromatographically separable. This oligomerization was used to synthesize a pentagalactan in a single step from monosaccharide building blocks in reasonable overall yields.

  3. Enteral Tube Feeding Nutritional Protein Hydrolysate Production Under Different Factors By Enzymatic Hydrolysis

    Nguyen ThiQuynhHoa; Nguyen Ngoc Phuong Diem; Nguyen Phuoc Minh; Dong ThiAnh Dao

    2015-01-01

    Abstract Hydrolysis of proteins involves the cleavage of peptide bonds to give peptides of varying sizes and amino acid composition. There are a number of types of hydrolysis enzymatic acid or alkali hydrolysis. Chemical hydrolysis is difficult to control and reduces the nutritional quality of products destroying L-form amino acids and producing toxic substances such as lysino-alanine. Enzymatic hydrolysis works without destructing amino acids and by avoiding the extreme temperatures and pH l...

  4. Identification of N-acylethanolamines in Dictyostelium discoideum and confirmation of their hydrolysis by fatty acid amide hydrolase[S

    Hayes, Alexander C.; Stupak, Jacek; Li, Jianjun; Cox, Andrew D.

    2013-01-01

    N-acylethanolamines (NAEs) are endogenous lipid-based signaling molecules best known for their role in the endocannabinoid system in mammals, but they are also known to play roles in signaling pathways in plants. The regulation of NAEs in vivo is partly accomplished by the enzyme fatty acid amide hydrolase (FAAH), which hydrolyses NAEs to ethanolamine and their corresponding fatty acid. Inhibition of FAAH has been shown to increase the levels of NAEs in vivo and to produce desirable phenotype...

  5. Hydrolysis and rearrangement of phthalamic acid derivatives and assessment of their potential as prodrug forms for amines

    Bundgaard, H; Steffansen, B

    1990-01-01

    various other N-alkyl and N-aryl substituted phthalamic acid derivatives were examined with the primary aim of assessing their degradation rate at physiological pH. Whereas the compounds I and II were indeed found to be easily degraded in neutral aqueous solutions, the degradation was not due to....... It is concluded that phthalamic acid derivatives are too stable chemically and enzymatically to be considered as prodrug forms for primary or secondary amines....

  6. Hydrolysis of uranium hexafluoride

    A literature survey is presented of uranium hexafluoride hydrolysis methods as the first step in UF6 conversion to UO2. Reviewed are early methods of hydrolysis, the hydrolysis by dry water vapour, the fluidized-bed method, and the liquid phase hydrolysis of UF6 gas. (J.P.)

  7. Enhanced enzymatic hydrolysis of pretreated almond-tree prunings for sugar production.

    Cuevas, Manuel; García, Juan Francisco; Sánchez, Sebastián

    2014-01-01

    Almond-tree prunings (ATP), an agricultural residue largely available in Mediterranean countries, were pretreated with either hot water or dilute sulphuric acid at 180-230 °C. Solids derived from hot water pretreatments were further submitted to alkaline peroxide delignification. In addition, all solids obtained from the three mentioned processes were hydrolysed by cellulases and β-glucosidases to investigate their enzymatic digestibilities. Hot water pretreatment led to high oligosaccharide yields (18.2 g/100 g ATP at 190 °C) while dilute acid pretreatment provided the highest monosaccharide yields (24.0 g/100 g ATP at 190 °C) along with low concentrations of fermentation inhibitors. Glucose yields from enzymatic hydrolysis were strongly affected by both pretreatment type and pretreatment temperature. The highest temperature assayed for both hydrothermal and dilute sulphuric acid pretreatment maximized the glucose recovery (49.2% and 72.8%, respectively) while solids derived from alkaline peroxide treatment achieved maximal glucose concentrations (41.9 g/L, 58.4% of potential yield). PMID:24274571

  8. Carbachol induces a rapid and sustained hydrolysis of polyphosphoinositide in bovine tracheal smooth muscle measurements of the mass of polyphosphoinositides, 1,2-diacylglycerol, and phosphatidic acid

    Takuwa, Y.; Takuwa, N.; Rasmussen, H.

    1986-11-05

    The effects of carbachol on polyphosphoinositides and 1,2-diacylglycerol metabolism were investigated in bovine tracheal smooth muscle by measuring both lipid mass and the turnover of (/sup 3/H)inositol-labeled phosphoinositides. Carbachol induces a rapid reduction in the mass of phosphatidylinositol 4,5-bisphosphate and phosphatidylinositol 4-monophosphate and a rapid increase in the mass of 1,2-diacylglycerol and phosphatidic acid. These changes in lipid mass are sustained for at least 60 min. The level of phosphatidylinositol shows a delayed and progressive decrease during a 60-min period of carbachol stimulation. The addition of atropine reverses these responses completely. Carbachol stimulates a rapid loss in (/sup 3/H)inositol radioactivity from phosphatidylinositol 4,5-bisphosphate and phosphatidylinositol 4-monophosphate associated with production of (/sup 3/H)inositol trisphosphate. The carbachol-induced change in the mass of phosphoinositides and phosphatidic acid is not affected by removal of extracellular Ca/sup 2 +/ and does not appear to be secondary to an increase in intracellular Ca/sup 2 +/. These results indicate that carbachol causes phospholipase C-mediated polyphosphoinositide breakdown, resulting in the production of inositol trisphosphate and a sustained increase in the actual content of 1,2-diacylglycerol. These results strongly suggest that carbachol-induced contraction is mediated by the hydrolysis of polyphosphoinositides with the resulting generation of two messengers: inositol 1,4,5-trisphosphate and 1,2-diacylglycerol.

  9. Determination of the main impurities formed after acid hydrolysis of soybean extracts and the in vitro mutagenicity and genotoxicity studies of 5-ethoxymethyl-2-furfural.

    Nemitz, Marina C; Picada, Jaqueline N; da Silva, Juliana; Garcia, Ana Letícia H; Papke, Débora K M; Grivicich, Ivana; Steppe, Martin; von Poser, Gilsane L; Teixeira, Helder F

    2016-09-10

    Soybean acid hydrolyzed extracts are raw-materials widely used for manufacturing of pharmaceuticals and cosmetics products due to their high content of isoflavone aglycones. In the present study, the main sugar degradation products 5-hydroxymethyl-2-furfural (HMF) and 5-ethoxymethyl-2-furfural (EMF) were quantitatively determined after acid hydrolysis of extracts from different soybean cultivars by a validated liquid chromatography method. The furanic compounds determined in samples cover the range of 0.16-0.21mg/mL and 0.22-0.33mg/mL for HMF and EMF, respectively. Complementarily, due to the scarce literature regarding the EMF toxicology, this study also assessed the EMF mutagenicity by the Salmonella/microsome test and genotoxicity by the comet assay. The results revealed that EMF did not show mutagenicity at the range of 50-5000μg/plate in S. typhimurium strains TA98, TA97a, TA100, TA102 and TA1535, but induced DNA damage in HepG2 cells at non-cytotoxic doses of 0.1-1.3mg/mL, mainly by oxidative stress mechanisms. Based on literature of HMF genotoxicity, and considering the EMF genotoxicity results herein shown, purification procedures to remove these impurities from extracts are recommended during healthcare products development to ensure the security of the products. PMID:27475406

  10. SYNTHESIS OF CONDENSATION POLYMERS OF SALICYLIC ACID, FORMALDEHYDE AND ALKYL PRIMARY AMINES AND ITS APPLICATION AS A CATALYST FOR THE HYDROLYSIS OF p-NITROPHENYL ACETATE (PNPA) IN AQUEOUS SOLUTION

    HE Binglin(Ho Pinglum); HUANG Wenqiang

    1983-01-01

    As a model of serine hydrolase, the condensation polymers of salicylic acid, formaldehyde and methyl amine, n-propyl amine, n-hexyl amine or n-lauryl amine were prepared by polycondensation catalyzed by sulfuric acid. It was confirmed by potentiometric titration and infrared spectrum that the polymers containing tertiary amino group possess the structure which resembles the internal salt of amino acid in weak basic and weak acidic solution:[-OOC-OH-CH2-H+N-R-CH2-]n R=alkyl group The catalytic reaction of the above polymers for hydrolysis of active ester,p-nitrophenyl acetate (PNPA),was studied .It was found kinetically that the most efficient catalytic effect of polymer was composed of two salicylic acid groups and one tertiary amino group in the polymer chain.The rates of hydrolysis of PNPA increase with increasing of pH values and length of the alkyl group in the side chain of the polymers and the effect of the conformation of the polymer containing tertiary amino group in the buffer solution on the catalytic activity was also investigated. Hydrolysis of PNPA catalyzed by the polymer made of salicylic acid, formaldehyde and n-lauryl amine follows the simple Michaelis-Menten type mechanism . The kinetics parameters were determined as :Km 6.7×10-5 M and Vmax 2.07×10-7 M·min-1.

  11. Influence of metal ion hydrolysis on the determination of complex stability constants as shown by lanthanide complexes of α-amino acids

    The conventional potentiometric methods for the determination of stability constants disregard the hydrolysis as a competing reaction for complex formation of cations, such as lanthanides. Two different ways for recording the metal hydrolysis are shown. It is assumed on appropriate conditions that only the first complex is formed. (author)

  12. Pathways of glucose regulation of monosaccharide transport in grape cells

    Conde, Carlos; Agasse, A.; Glissant, David; Tavares, R. M.; Gerós, H.; Delrot, Serge

    2006-01-01

    Grape (Vitis vinifera) heterotrophic suspension-cultured cells were used as a model system to study glucose (Glc) transport and its regulation. Cells transported D-[14C]Glc according to simple Michaelis-Menten kinetics superimposed on first-order kinetics. The saturating component is a high-affinity, broad-specificity H+-dependent transport system (Km = 0.05 mM). Glc concentration in the medium tightly regulated the transcription of VvHT1 (Vitis vinifera hexose transporter 1), a monosaccharid...

  13. Statistical Optimization for Acid Hydrolysis of Microcrystalline Cellulose and Its Physiochemical Characterization by Using Metal Ion Catalyst

    Md. Ziaul Karim

    2014-10-01

    Full Text Available Hydrolyzing the amorphous region while keeping the crystalline region unaltered is the key technology for producing nanocellulose. This study investigated if the dissolution properties of the amorphous region of microcrystalline cellulose can be enhanced in the presence of Fe3+ salt in acidic medium. The process parameters, including temperature, time and the concentration of metal chloride catalyst (FeCl3, were optimized by using the response surface methodology (RSM. The experimental observation demonstrated that temperature and time play vital roles in hydrolyzing the amorphous sections of cellulose. This would yield hydrocellulose with higher crystallinity. The factors that were varied for the production of hydrocellulose were the temperature (x1, time (x2 and FeCl3 catalyst concentration (x3. Responses were measured in terms of percentage of crystallinity (y1 and the yield (y2 of the prepared hydrocellulose. Relevant mathematical models were developed. Analysis of variance (ANOVA was carried out to obtain the most significant factors influencing the responses of the percentage of crystallinity and yield. Under optimum conditions, the percentage of crystallinity and yield were 83.46% and 86.98% respectively, at 90.95 °C, 6 h, with a catalyst concentration of 1 M. The physiochemical characteristics of the prepared hydrocellulose were determined in terms of XRD, SEM, TGA and FTIR analyses. The addition of FeCl3 salt in acid hydrolyzing medium is a novel technique for substantially increasing crystallinity with a significant morphological change.

  14. Structural basis for the hydrolysis of ATP by a nucleotide binding subunit of an amino acid ABC transporter from Thermus thermophilus.

    Devi, Seenivasan Karthiga; Chichili, Vishnu Priyanka Reddy; Jeyakanthan, J; Velmurugan, D; Sivaraman, J

    2015-06-01

    ATP-binding cassette (ABC) transporters are a major family of small molecule transporter proteins, and their deregulation is associated with several diseases, including cancer. Here, we report the crystal structure of the nucleotide binding domain (NBD) of an amino acid ABC transporter from Thermus thermophilus (TTHA1159) in its apo form and as a complex with ADP along with functional studies. TTHA1159 is a putative arginine ABC transporter. The apo-TTHA1159 was crystallized in dimeric form, a hitherto unreported form of an apo NBD. Structural comparison of the apo and ADP-Mg(2+) complexes revealed that Phe14 of TTHA1159 undergoes a significant conformational change to accommodate ADP, and that the bound ADP interacts with the P-loop (Gly40-Thr45). Modeling of ATP-Mg(2+):TTHA1159 complex revealed that Gln86 and Glu164 are involved in water-mediated hydrogen bonding contacts and Asp163 in Mg(2+) ion-mediated hydrogen bonding contacts with the γ-phosphate of ATP, consistent with the findings of other ABC transporters. Mutational studies confirmed the necessity of each of these residues, and a comparison of the apo/ADP Mg(2+):TTHA1159 with its ATP-complex model suggests the likelihood of a key conformational change to the Gln86 side chain for ATP hydrolysis. PMID:25916755

  15. Ultrasound-assisted enzymatic hydrolysis for iodinated amino acid extraction from edible seaweed before reversed-phase high performance liquid chromatography-inductively coupled plasma-mass spectrometry.

    Romarís-Hortas, Vanessa; Bermejo-Barrera, Pilar; Moreda-Piñeiro, Antonio

    2013-09-27

    The combination of reverse phase high performance liquid chromatography (RP-HPLC) with inductively coupled plasma mass spectrometry (ICP-MS) was used for the determination of monoiodotyrosine (MIT) and diiodotyrosine (DIT) in edible seaweed. A sample pre-treatment based on ultrasound assisted enzymatic hydrolysis was optimized for the extraction of these iodinated amino acids. Pancreatin was selected as the most adequate type of enzyme, and parameters affecting the extraction efficiency (pH, temperature, mass of enzyme and extraction time) were evaluated by univariate approaches. In addition, extractable inorganic iodine (iodide) was also quantified by anion exchange high performance liquid chromatography (AE-HPLC) coupled with ICP-MS. The proposed procedure offered limits of detection of 1.1 and 4.3ngg(-1) for MIT and DIT, respectively. Total iodine contents in seaweed, as well as total iodine in enzymatic digests were measured by ICP-MS after microwave assisted alkaline digestion with tetramethylamonium hydroxide (TMAH) for total iodine assessment, and also by treating the pancreatin extracts (extractable total iodine assessment). The optimized procedure was successfully applied to five different types of edible seaweed. The highest total iodine content, and also the highest iodide levels, was found in the brown seaweed Kombu (6646±45μgg(-1)). Regarding iodinated amino acids, Nori (a red seaweed) was by far the one with the highest amount of both species (42±3 and 0.41±0.024μgg(-1) for MIT and DIT, respectively). In general, MIT concentrations were much higher than the amounts of DIT, which suggests that iodine from iodinated proteins in seaweed is most likely bound in the form of MIT residues. PMID:23972456

  16. The use of superporous p(AAc (acrylic acid)) cryogels as support for Co and Ni nanoparticle preparation and as reactor in H2 production from sodium borohydride hydrolysis

    Here, we report for the first time the use of p(AAc (p(acrylic acid)) cryogel for in situ metal nanoparticle preparation, and their use as a superporous reactor for H2 generation from hydrolysis of NaBH4. Superporous p(AAc) cryogels and conventional hydrogels were prepared via free radical polymerization technique at low (−18 °C) and moderate (40 °C) temperatures, respectively. They were characterized by employing various methods such as swelling experiments, optical imaging, and SEM (Scanning Electron Microscopy) analysis. By reducing Co2+ and Ni2+ ions within p(AAc) cryogel and hydrogel matrices, the obtained Co and Ni metal nanoparticles were employed for H2 generation from NaBH4 hydrolysis. Various factors such as porosity, metal type, temperature, and the amount of sodium hydroxide were investigated to determine their effects on hydrogen generation from NaBH4 hydrolysis. Activation energy (Ea), enthalpy (ΔH#) and entropy (ΔS#) for NaBH4 hydrolysis by superporous p(AAc)-Co metal composites were 29.35 kJ mol−1,=36.85 kJ mol−1, and –157.88 J mol−1K−1, respectively. Cryogels showed better catalytic activity than conventional hydrogels in the hydrolysis reaction, and have a higher TOF (turnover frequency) value of 4.10 mol H2 (mol catalyst min)−1 compared to conventional hydrogels, due to its highly porous nature, short diffusion distances and fast response times. - Highlights: • Superporous cryogel supports for in situ metal nanoparticle preparation. • Fast H2 production from chemical hydride hydrolysis by cryogel-M composites. • Soft, superporous cryogel reactors for energy applications

  17. Monosaccharide transport into hemocytes of a sipunculan worm Themiste dyscrita

    The hemerythrin-containing blood cells, or hemocytes, of the sipunculan worm Themiste dyscrita were found to have a stereospecific and nonconcentrative monosaccharide transport system. The transport system transferred both D-glucose and 3-O-methyl-D-glucose (3-OMG), and transport into cells by this system was rapid, reaching 50% equilibrium in approximately 20 s at 10 degrees C with an initial concentration gradient of 0.1 mM; the contribution to total uptake by simple diffusion was very small. 3-OMG uptake showed saturation kinetics with a low half-saturation constant (Km less than or equal to 0.1 mM). The uptake of labeled 3-OMG by the hemocytes was strongly inhibited by unlabeled 3-OMG, 2-deoxy-D-glucose, alpha- and beta-D-glucose, D-galactose, and D-mannose. It was moderately inhibited by D-xylose, only slightly by alpha-methyl-D-glucoside and D-fructose, and uninhibited by sucrose, L-glucose, or D-sorbitol. Phloretin was more potent than phloridzin in blocking entry of 3-OMG. Cytochalasin B did not bind tightly to the T. dyscrita transporter and was not a potent inhibitor of transport; it half-maximally inhibited 3-OMG transport at 0.1 mM. Therefore, despite some differences the data suggest functional similarities in the mechanism of monosaccharide transport into blood cells of mammals and this invertebrate

  18. 乙酸法制浆副产物半纤维素水解的初步研究%A study on hydrolysis of degraded hemicellulose separated by acetosolv pulping

    黄国红; 敖日格勒; 庞春生

    2012-01-01

      Acetosolv pulping can easily fractionate plenty of hemicellulose as by-product. The separated hemicellulose from corn stalk by acetosolv pulping was hydrolyzed by dilute sulfuric acid and monosaccharide components in hemicellulose fractionation and hydrolysis were investigated by ion exchange chromatogram. The results show that there is about 10%monosaccharides in hemicellulose fractionation. Low sulfuric acid concentration(1%) and long hydrolysis time(2h) can get maximum amount of monosaccharides, about 38%. Content of xylose and glucose would be substantially cut down when sulfuric acid concentration rises over 1% for xylose and 2% for glucose. Contents of mannose rise as sulfuric acid concentration increases, but contents of arabinose, galactose varies little when sulfuric acid concentration changes.%  乙酸法制浆可以分离得到较大含量的半纤维素副产物,且分离方法简单。利用离子色谱分析了玉米秸秆乙酸制浆副产物半纤维素糖溶液中的单糖组成情况,并对其进行水解,分析了水解条件对单糖组成的影响。结果表明:玉米秸秆乙酸制浆副产物半纤维素糖溶液中约有10%左右的单糖;低硫酸浓度(1%)和较长水解时间(2h)时获得的单糖总量最大,能达到38%左右;增加硫酸浓度(大于1%),木糖降低幅度很大;硫酸浓度大于2%时,葡萄糖进一步降解反应也很明显;增加硫酸浓度有利于低聚糖降解得到甘露糖,但阿拉伯糖、半乳糖受硫酸浓度变化的影响很小。

  19. Aiming for the complete utilization of sugar-beet pulp: Examination of the effects of mild acid and hydrothermal pretreatment followed by enzymatic digestion

    Kuhnel, S.; Schols, H.A.; Gruppen, H.

    2011-01-01

    Background - Biomass use for the production of bioethanol or platform chemicals requires efficient breakdown of biomass to fermentable monosaccharides. Lignocellulosic feedstocks often require physicochemical pretreatment before enzymatic hydrolysis can begin. The optimal pretreatment can be differe

  20. Regioselective deprotection of the monosaccharide-bearing thiocyanomethyl group at the anomeric position monitored by reversed-phase HPLC method.

    Abualassal, Qais; Al Azzam, Khaldun M; Jilani, Jamal A

    2016-09-01

    In the current work, the investigation and development of a chemo-enzymatic approach for the synthesis of neo-glycoproteins have been studied. This strategy is based on the regioselective enzymatic hydrolysis of peracetylated monosaccharide, functionalized at the anomeric position (C1) as 1-thio-(S-cyanomethyl) group, a precursor of the 2- iminomethoxyethyl thioglycosides-linker for protein glycosylation, catalyzed by immobilized enzymes to obtain selectively monodeprotected compounds. The use of this activation in C1 is the most frequently used strategy for glycoprotein preparation. The selected biocatalysts are the lipase from Candida rugosa and the acetyl xylan esterase from Bacillus pumilus. A reversed-phase high-performance liquid-chromatographic (HPLC) method for monitoring the regioselective deprotection reaction has been developed. The developed HPLC method was used as a fingerprint to follow the hydrolysis of substrate 1 to substrate 1a and to determine its purity and yield. Moreover, the obtained compound was further purified by flash chromatography. The obtained compound 1a was further characterized using (1) H, (13) C NMR, correlation spectroscopy (COSY) and heteronuclear multiple bond correlation. The resulting product can be used as an intermediate for the preparation of di- and more complex oligosaccharides aimed at protein conjugation. Copyright © 2016 John Wiley & Sons, Ltd. PMID:26864255

  1. Molecular Weight and Monosaccharide Composition of Astragalus Polysaccharides

    Pei-Pei Wang

    2008-10-01

    Full Text Available Two polysaccharides (APS-I and APS-II were isolated from the water extract of Radix Astragali and purified through ethanol precipitation, deproteination and by ion-exchange and gel-filtration chromatography. Their molecular weight was determined using high performance liquid chromatography and gel permeation chromatography (HPLC-GPC and their monosaccharide composition was analyzed by TLC and HPLC methods, using a refractive index detector (RID and an NH2 column. It was shown that APS-I consisted of arabinose and glucose and APS-II consisted of rhamnose, arabinose and glucose, in a molar ratio of 1:3.45 and 1:6.25:17.86, respectively. The molecular weights (Mw of APS-I and APS-II were 1,699,100 Da and 1,197,600 Da, respectively.

  2. Basic Dynamics Research of Hemicellulose Hydrolysis by the Solid Acid%固体酸催化半纤维素水解的基础动力学研究

    项巍; 朱建良

    2011-01-01

    [目的]研究固体酸催化玉米桔秆半纤维素水解的基础动力学.[方法]单因素试验确定最佳固体酸种类、固固比、固液比,然后在以上最优条件下,综合考察反应温度和时间对半纤维素水解产率的影响.[结果]固体酸催化玉米秸秆半纤维素水解的最适反应条件:2号固体酸为催化剂,固固比1:1,固液比1:15,反应温度100℃,反应时间10 h.在该最适条件下,可溶性总糖浓度为34.7 g/L,半纤维素水解产率为93.8%.[结论]该研究为固体酸降解玉米秸秆工艺的优化和放大设计提供了基础动力学数据.%[Objective] The research aimed to study the basic dynamics of corn straw hemicellulose hydrolysis by the solid acid. [ Method ] The optimal solid acid class,solid-solid ratio,solid-liquid ratio were determined by the single factor experiment. Then,under the above best condition , the influences of reaction temperature and time on the hydrolysis rate of hemicellulose were comprehensively inspected. [ Result ] The optimal reaction condition of corn straw hemicellulose hydrolysis by the solid acid: number 2 solid acid as the catalyst, the solid-solid ratio was 1 : 1 ,the solid-liquid ratio was 1:15, the reaction temperature was 100 ℃ ,and the reaction time was 10 h. Under the optimal condition, the soluble total sugar concentration was 34.7 g/L,and the hydrolysis rate of hemicellulose was 93.8%. [ Conclusion] The research provided the basic dynamics data for the optimization and amplification design of com straw hydrolysis technics by the solid acid.

  3. 基于3,5-二硝基水杨酸法的水稻秸秆酶解工艺%Enzymatic Hydrolysis of Rice Straw Based on 3,5-dinitrosalicylic Acid Method

    李彬; 高翔; 孙倩; 陈坤杰

    2013-01-01

    For the purpose to improve the conversion rate of reducing sugar of rice straw, the cellulose was used in the enzymatic hydrolysis of rice straw. The content of reducing sugar was detected by 3,5-dinitrosalicylic acid method. The enzyme concentration, hydrolysis time and temperature were selected as inspecting factors. Meantime, comparisons of the enzymatic hydrolysis of rural rice straw with that of steam explosion pretreatment rice straw were made. The results showed when the cellulose weight content taking 10% of the dry rice straw, enzymatic hydrolysis time of 48 h and reaction temperature of 50℃ were ideal reaction conditions. The maximum reducing sugar yield of enzymatic hydrolysis original rice straw was 9.7% . The highest reducing sugar yield of enzymatic hydrolysis steam explosion rice straw was approximately 34. 3 %. Steam explosion pretreatment can obviously improve the production of reducing sugar of enzymatic hydrolysis rice straw, and at the same time accelerate the reaction rate.%为了提高汽爆水稻秸秆还原糖的转化率,采用纤维素酶对水稻秸秆进行酶解实验.还原糖的含量用3,5-二硝基水杨酸法进行测定.实验选用加酶量、酶解时长和反应温度作为考察因素,以原始水稻秸秆与蒸汽爆破预处理水稻秸秆作对比.结果表明纤维素酶用量占秸秆干物质质量的10%,酶解时长48 h,反应温度50℃是一个较为理想的反应条件;原始水稻秸秆最大酶解还原糖产量约为9.7%;蒸汽爆破水稻秸秆最大酶解还原糖产量约为34.3%;蒸汽爆破预处理能够显著提高水稻秸秆的酶解还原糖产量,并缩短酶解反应时间.

  4. Molecular cloning and expression analysis of a monosaccharide transporter gene OsMST4 from rice (Oryza sativa L.)

    Wang, Y.; Xu, H.; Wei, X.; Chai, C.; Xiao, Y.; Zhang, Y.; Chen, B.; Xiao, G.; Ouwerkerk, P.B.F.; Wang, M.; Zhu, Z.

    2007-01-01

    Monosaccharide transporters mediate the membrane transport of a variable range of monosaccharides, which plays a crucial role in sugar distribution throughout the plant. To investigate the significance of monosaccharide transporters for rice (Oryza sativa L.) seed development, cDNA of a new putative

  5. A sensitive and efficient method for determination of N-acetylhexosamines and N-acetylneuraminic acid in breast milk and milk-based products by high-performance liquid chromatography via UV detection and mass spectrometry identification.

    Chuanxiang, Wu; Lian, Xia; Lijie, Liu; Fengli, Qu; Zhiwei, Sun; Xianen, Zhao; Jinmao, You

    2016-02-01

    A sensitive and efficient method of high performance liquid chromatography using 1-(2-naphthyl)-3-methyl-5-pyrazolone (NMP) as pre-column derivatization reagent coupled with UV detection (HPLC-UV) and online mass spectrometry identification was established for determination of the most common N-Acetylhexosamines (N-acetyl-d-glucosamine (GlcNAc) and N-acetyl-d-galactosamine (GalNAc)) and N-acetylneuraminic acid (Neu5Ac). In order to obtain the highest liberation level of the three monosaccharides without destruction of Neu5Ac or conversion of GlcNAc/GalNAc to GlcN/GalN in the hydrolysis procedure, the pivotal parameters affecting the liberation of N-acetylhexosamines/Neu5Ac from sample were investigated with response surface methodology (RSM). Under the optimized condition, maximum yield was obtained. The effects of key parameters on derivatization, separation and detection were also investigated. At optimized conditions, three monosaccharides were labeled fast and entirely, and all derivatives exhibited a good baseline resolution and high detection sensitivity. The developed method was linear over the calibration range 0.25-12μM, with R(2)>0.9991. The detection limits of the method were between 0.48 and 2.01pmol. Intra- and inter-day precisions for the three monosaccharides (GlcNAc, GalNAc and Neu5Ac) were found to be in the range of 3.07-4.02% and 3.69-4.67%, respectively. Individual monosaccharide recovery from spiked milk was in the range of 81%-97%. The sensitivity of the method, the facility of the derivatization procedure and the reliability of the hydrolysis conditions suggest the proposed method has a high potential for utilization in routine trace N-acetylhexosamines and Neu5Ac analysis in biological samples. PMID:26751589

  6. Enthalpy and entropy interaction parameters of sodium chloride with some monosaccharides in water

    ZHUO; Kelei; WANG; Jianji; BAI; Guangyue; YAN; Haike; WANG

    2004-01-01

    Dilution enthalpies of sodium chloride and some monosaccharides (glucose, galactose, xylose, arabinose, and fructose) in water and mixing enthalpies of aqueous sodium chloride and these monosaccharide solutions were measured by using an improved precision semimicro-titration calorimeter. Transfer enthalpies of sodium chloride from water to aqueous saccharide solutions were evaluated as well as enthalpy interaction parameters of sodium chloride with these monosaccharides in water. Combined with Gibbs energy interaction parameters, entropy interaction parameters were also obtained. The results show that interactions of the saccharides with sodium chloride depend on the stereochemistry of saccharide molecules. These interaction parameters can identify stereochemical structure of saccharide molecules.

  7. Pretreatment of dried distillers grains with solubles by soaking in aqueous ammonia and subsequent enzymatic/dilute acid hydrolysis to produce fermentable sugars

    Dried distillers grains with solubles (DDGS), a co-product of corn ethanol production in the dry-grind process, was pretreated by soaking in aqueous ammonia (SAA) using a 15% w/w NH4OH solution at a solid:liquid ratio of 1:10. The effect of pretreatment on subsequent enzymatic hydrolysis was studied...

  8. Thioglycoside hydrolysis catalyzed by β-glucosidase

    Sweet almond β-glucosidase (EC 3.2.1.21) has been shown to have significant thioglycohydrolase activity. While the Km values for the S- and O-glycosides are similar, the kcat values are about 1000-times lower for the S-glycosides. Remarkably, the pH-profile for kcat/Km for hydrolysis of p-nitrophenyl thioglucoside (pNPSG) shows the identical dependence on a deprotonated carboxylate (pKa 4.5) and a protonated group (pKa 6.7) as does the pH-profile for hydrolysis of the corresponding O-glycoside. Not surprisingly, in spite of the requirement for the presence of this protonated group in catalytically active β-glucosidase, thioglucoside hydrolysis does not involve general acid catalysis. There is no solvent kinetic isotope effect on the enzyme-catalyzed hydrolysis of pNPSG

  9. Diverse Functional Roles of Monosaccharide Transporters and their Homologs in Vascular Plants: A Physiological Perspective

    Thomas L. Slewinski

    2011-01-01

    Vascular plants contain two gene families that encode monosaccharide transporter proteins. The classical monosaccharide transporter(-like)gene superfamily is large and functionally diverse, while the recently identified SWEET transporter family is smaller and, thus far, only found to transport glucose. These transporters play essential roles at many levels, ranging from organelles to the whole plant. Many family members are essential for cellular homeostasis and re-productive success. Although most transporters do not directly participate in long-distance transport, their indirect roles greatly impact carbon allocation and transport flux to the heterotrophic tissues of the plant. Functional characterization of some members from both gene families has revealed their diverse roles in carbohydrate partitioning, phloem function,resource allocation, plant defense, and sugar signaling. This review highlights the broad impacts and implications of monosaccharide transport by describing some of the functional roles of the monosaccharide transporter(-like)superfamily and the SWEET transporter family.

  10. Effect of Selected Monosaccharide on Growth and Putrescine Production of Serratia marcescens

    Pleva, P.; Lazárková, Z.; Andresová, Adéla; Lorencová, E.; Buňka, F.; Buňková, L.

    2012-01-01

    Roč. 28, SI (2012). ISSN 0322-7340 Grant ostatní: UTB(CZ) IGA/FT/2012/027 Institutional support: RVO:67985858 Keywords : monosaccharides * chromatography * microbial metabilic activity Subject RIV: CF - Physical ; Theoretical Chemistry

  11. Novel double prodrugs of the iron chelator N,N'-bis(2-hydroxybenzyl)ethylenediamine-N,N'-diacetic acid (HBED): Synthesis, characterization, and investigation of activation by chemical hydrolysis and oxidation.

    Thiele, Nikki A; Abboud, Khalil A; Sloan, Kenneth B

    2016-08-01

    The development of iron chelators suitable for the chronic treatment of diseases where iron accumulation and subsequent oxidative stress are implicated in disease pathogenesis is an active area of research. The clinical use of the strong chelator N,N'-bis(2-hydroxybenzyl)ethylenediamine-N,N'-diacetic acid (HBED) and its alkyl ester prodrugs has been hindered by poor oral bioavailability and lack of conversion to the parent chelator, respectively. Here, we present novel double prodrugs of HBED that have the carboxylate and phenolate donors of HBED masked with carboxylate esters and boronic acids/esters, respectively. These double prodrugs were successfully synthesized as free bases (7a-f) or as dimesylate salts (8a-c,e), and were characterized by (1)H, (13)C, and (11)B NMR; MP; MS; and elemental analysis. The crystal structure of 8a was solved. Three of the double prodrugs (8a-c) were selected for further investigation into their abilities to convert to HBED by stepwise hydrolysis and H2O2 oxidation. The serial hydrolysis of the pinacol and methyl esters of N,N'-bis(2-boronic acid pinacol ester benzyl)ethylenediamine-N,N'-diacetic acid methyl ester dimesylate (8a) was verified by LC-MS. The macro half-lives for the hydrolyses of 8a-c, measured by UV, ranged from 3.8 to 26.3 h at 37 °C in pH 7.5 phosphate buffer containing 50% MeOH. 9, the product of hydrolysis of 8a-c and the intermediate in the conversion pathway, showed little-to-no affinity for iron or copper in UV competition experiments. 9 underwent a serial oxidative deboronation by H2O2 in N-methylmorpholine buffer to generate HBED (k = 10.3 M(-1) min(-1)). The requirement of this second step, oxidation, before conversion to the active chelator is complete may confer site specificity when only localized iron chelation is needed. Overall, these results provide proof of principle for the activation of the double prodrugs by chemical hydrolysis and H2O2 oxidation, and merit further investigation into the

  12. HYDROLYSIS OF PAPER-DISHWARE WASTES BY CELLULASE

    Jie Lu; Shulan Shi; Runan Yang; Fuzheng Liang

    2004-01-01

    The optimum conditions of hydrolysis of cellulosic wastes by cellulase were studied. The results show that the optimum conditions of sulfuric acid pretreatment were sulfuric acid consistency 0.3M,pretreatment temperature 100℃, pretreatment time 4hours. After sulfuric acid pretreatment, the optimum conditions of hydrolysis by cellulase were enzymatic temperature 50℃ ,enzymatic time 48hours,pH4.8,the charge of cellulase 100IU/g and the substraste consistency 60g/l. Meanwhile this paper studies that the structural change of cellulose during sulfuric acid pretreatment and cellulase hydrolysis by analyzing the infrared spectra.

  13. HYDROLYSIS OF PAPER-DISHWARE WASTES BY CELLULASE

    JieLu; ShulanShi; RunanYang; FuzhengLiang

    2004-01-01

    The optimum conditions of hydrolysis of cellulosic wastes by cellulase were studied. The results show that the optimum conditions of sulfuric acid pretreatment were sulfuric acid consistency 0.3M, pretreatment temperature 100℃, pretreatment time 4hours. After sulfuric acid pretreatment, the optimum conditions of hydrolysis by cellulase were enzymatic temperature 50℃, enzymatic time 48hours,pH4.8,the charge of cellulase 100IU/g and the substraste consistency 60g/l. Meanwhile this paper studies that the structural change of cellulose during sulfuric acid pretreatment and cellulase hydrolysis by analyzing the infrared spectra.

  14. Neutral monosaccharides from a hypersaline tropical environment: Applications to the characterization of modern and ancient ecosystems

    Moers, M. E. C.; Larter, S. R.

    1993-07-01

    Surficial and buried sediment samples from a hypersaline lagoon-sabkha system (Abu Dhabi, United Arab Emirates) were analysed for carbohydrates (as neutral monosaccharides) to distinguish and characterise various types of recent and ancient tropical ecosystems on a molecular level. The samples consisted of surficial and buried microbial mats, lagoonal sediments containing seagrass ( Halodule uninervis), and mangrove ( Avicennia marina) paleosoils and handpicked mangrove leaves, ranging in age from contemporary to ca. 6000 yr Bp. Analysis of quantitative neutral monosaccharide data by multivariate techniques shows that various groups can be distinguished: intact vascular plant material (mangrove leaf) contains high amounts of arabinose and glucose and hardly any partially methylated monosaccharides, whereas microbial mats in general and lagoonal seagrass sediments show high contributions of fucose, ribose, mannose, galactose and partially methylated monosaccharides. Moreover, surficial microbial mats consisting of filamentous cyanobacteria ( Microcoleus chtonoplastes, Lyngbya aestuarii) can be distinguished from other mats and sediments containing coccoid cyanobacteria ( Entophysalis major) and/or fermenting, sulphate reducing, and methanogenic bacteria on the basis of high contributions of specific groups of partially methylated monosaccharides and other "minor" saccharides. The neutral monosaccharides present in mangrove paleosoils are for a substantial part derived from microorganisms.

  15. Analytical Approaches of Determining Monosaccharides from Alkaline-Treated Palm Fiber

    Monosaccharides in oil palm empty fruit bunch fiber (EFB) were determined by methanolysis and acetylation. Three types of EFB samples, namely untreated EFB, EFB pretreated with hot water and EFB pretreated with hot water followed by 10 % (w/ w) sodium hydroxide (NaOH) aqueous solution were used. The FTIR spectrum indicated the disappearance and shifting of aromatic and carbonyl functional groups, syringyl propane unit, guaisacyl propane unit and C-H lignin. The filter cake undergone methanolysis and alditol acetate treatments to detect the composition of reducing sugars. Gas chromatography flame ionization detector (GC-FID) analysis was conducted to determine the type and quantity of reducing sugars produced. Acetylation produced two types of monosaccharides namely glucose and galactose whereas methanolysis detected only one type of monosaccharide, which was xylose. The extracted monosaccharides obtained from hot water pretreatment followed by 10 % (w/ w) NaOH aqueous solution treatment analysed by methanolysis and acetylation were 178.4 mg/ g xylose and 29.9 mg/ g glucose respectively. About 0.76 mg/ g xylose was extracted from hot water pretreated EFB fiber by methanolysis. Acetylation detected monosaccharides in untreated EFB and identified as glucose with the amount of 19.15 mg/ g, whereas monosaccharides from hot water pretreated EFB fiber were identified as glucose and galactose at 6.32 mg/ g and 2.83 mg/ g respectively. (author)

  16. Selective Acid Hydrolysis Condition for the Composition and Linkage with a Fructofuranosyl Backbone of a Polysaccharide from Angelica sinensis (Oliv) Diels

    Gui Yun XU; Yang CHEN; Ru Xian CHEN

    2006-01-01

    A new polysaccharide was extracted and purified from the roots of Angelica sinensis (Oliv) Diels (ASD). Its composition and linkage was elucidated by selective hydrolysis and GC/MS analysis of its derivatives. The polysaccharide was made of→1) Fruf(2→and→6) GlCp (1→as its backbone with highly branched structure. To our best knowledge, this is the first report of the fructose residue in polysaccharides from the roots of the ASD.

  17. Hydrolysis of sunflower proto pectin in static and dynamic mode

    The article describes a hydrolysis process of sunflower head residue by using state and dynamics regime of hydrolysis. It's shown that application of dynamics method positively influences on the pectin yields and its main parameters. The results of comparative study of acid concentration effect on pectin parameters in two different hydrolysis mode allows to develop a more effective process in the pectin production. (author)

  18. Fundamental study of the mechanism and kinetics of cellulose hydrolysis by acids and enzymes. Final report, June 1, 1978-January 31, 1981

    Gong, C.S.; Chang, M.

    1981-02-01

    There are three basic enzymes (e.g., endoglucanase (C/sub x/), exoglucanase (C/sub 1/) and cellobiase) comprising the majority of extracellular cellulase enzymes produced by the cellulolytic mycelial fungi, Trichoderma reesei, and other cellulolytic microorganisms. The enzymes exhibited different mode of actions in respect to the hydrolysis of cellulose and cellulose derived oligosaccharides. In combination, these enzymes complimented each other to hydrolyze cellulose to its basic constituent, glucose. The kinetics of cellobiase were developed on the basis of applying the pseudo-steady state assumption to hydrolyze cellobiose to glucose. The results indicated that cellobiase was subjected to end-product inhibition by glucose. The kinetic modeling of exoglucanase (C/sub 1/) with respect to cellodextrins was studied. Both glucose and cellobiose were found to be inhibitors of this enzyme with cellobiose being a stronger inhibitor than glucose. Similarly, endoglucanase (C/sub x/) is subject to end-product inhibition by glucose. Crystallinity of the cellulose affects the rate of hydrolysis by cellulases. Hence, the changes in crystallinity of cellulose in relation to chemical pretreatment and enzyme hydrolysis was compared. The study of cellulase biosynthesis resulted in the conclusion that exo- and endo-glucanases are co-induced while cellobiase is synthesized independent of the other two enzymes. The multiplicity of cellulase enzymes are the end results of post-translational modification during and/or after the secretion of enzymes into growth environment.

  19. Hydrolysis of soy isoflavone conjugates using enzyme may underestimate isoflavone concentrations in tissue

    Hebron C. Chang; Myriam Laly; Melody Harrison; Thomas M. Badger

    2005-01-01

    Objective: To investigate the differences of using enzymatic hydrolysis and acid hydrolysis for identification and quantification of isoflavone aglycones from biomatrices. Methods: β-glucuronidase/sulfatase isolated from Helix pomatia for routine enzymatic hydrolysis or 6N HCl was used to release glucuronide and sulfate conjugates in the serum, urine and tissue samples. Profiles of soy isoflavones after enzymatic hydrolysis or acid hydrolysis in several tissues of rat fed with diets containing soy protein isolate were also compared using LC/MS and HPLC-ECD. Results: Acid hydrolysis released more aglycone than enzymatic digestion ( P <0.05) in liver tissue. The total genistein, daidzein and other metabolites were 20% to 60% lower in samples from enzymatic hydrolysis than in acid hydrolysis. Conclusion: These results indicated that unknown factors in tissues reduced the enzymatic hydrolytic efficiency for releasing isoflavone aglycones even in optimized condition. This would underestimate isoflavone tissue concentrations up to 60%.

  20. 白首乌中C21甾总苷盐酸水解条件的优化%Study on Optimization of the Hydrolysis Process of C21 Steroidal Glycoside of Bai Shou Wu by Hydrochloric Acid

    赵鑫; 沈舒; 李友宾

    2011-01-01

    Objective To study the optimization of hydrolysis process of C21 steroidal glycoside of Bai Shou Wu by hydrochloric acid. Methods The effects of hydrochloric acid concentration, reaction temperature and reaction time had been investigated using orthogonal design with caudatin-3-O-β-D-cymaropyranosyl content as the index. Results The optimum hydrolysis condition was as follows: refluxing for 5 h with 50 mL of 0.5% dilute HCl solution at 60 ℃. Conclusion The content of active ingredients in general steroidal glycosides of Bai Shou Wu under the optimum hydrolysis condition is raised obviously and has a great part in improving anti-tumor activity.%目的 研究白首乌C21甾总苷盐酸水解的最优水解条件.方法 采用正交试验法,考察水解时间、水解温度、盐酸浓度等因素对告达庭-3-O-β-D-磁麻糖苷含量的影响.结果 影响盐酸水解的最优水解条件为:0.5%盐酸溶液,60℃加热回流5 h.结论 优化的水解条件能明显提高白首乌总苷中有效成分的含量,对进一步研究白首乌总苷抗肿瘤活性的增强具有一定意义.

  1. Synthesis and hydrolysis resisting capacity of ethoxylated ricinoleic acid methyl esters%蓖麻油酸甲酯乙氧基化物的合成与耐酸耐碱性研究

    张谦; 孙永强; 王万绪; 智丽飞; Martino Di Serio; 刘伟

    2015-01-01

    Ethoxylated ricinoleic acid methyl esters (ECAME - 10)obtained directly from castor oil acid methyl esters by the use of a special homogeneous catalyst. The average ethylene oxide (EO)adduct number of ECAME - 10 was determined by saponification value,gas chromatography (GC)and 1 HNMR. The hydrolysis resisting capacity of ECAME - 10 was investigated under different pH value conditions. The appearance changes of ECAME - 10 solution under different storing time periods was tracked and photographed and surface tension of different stages of the solution at different stages was measured. Results showed that the hydrolysis resisting capacity of ECAME - 10 is rather strong. The hydrolysis rate of ECAME - 10 is below 40% in pH value range of 4 - 9 after eight weeks. Surface tension of solutions can be kept stable after the hydrolysis reaction.%在一定的温度和压力条件下,以及特制的均相催化剂作用下,直接由蓖麻油酸甲酯得到了产物蓖麻油酸甲酯乙氧基化物(ECAME -10)。通过皂化值、气相色谱(GC)和1 HNMR 测定了ECAME -10的平均环氧乙烷(EO)加合数,在不同pH条件下测定了ECAME -10的耐酸耐碱性,并跟踪拍摄了不同pH溶液不同阶段的外观照片,同时测定了不同阶段溶液的表面张力。结果显示:ECAME -10有较强的抗水解能力,当pH =4~9时,ECAME -10的水解较慢,8周后其水解率在40%以下;水解后的表面张力数据表明,水解后溶液的表面张力可保持稳定。

  2. 酶解条件对透明质酸提取及其分子量分布的影响%Effects of Enzymatic Hydrolysis on Quality and Molecular Weight Distribution of Hyaluronic Acid Extracted from Rooster Comb

    陈涛; 丁淑敏; 王利群

    2011-01-01

    使用胃蛋白酶和胰蛋白酶从鸡冠中提取透明质酸,考察不同酶解条件对透明质酸质量与分子量分布的影响.结果显示,胃蛋白酶用量30 g/kg,胰蛋白酶用量3 g/kg,各酶解2h,胰蛋白酶酶解pH 8.5,酶解温度45℃时,透明质酸得率为0.5%~0.6%,葡萄糖醛酸含量为41.2%~44.3%,透明质酸平均相对分子质量大于1.0× 106,分子量分布指数接近1.%The effects of enzymatic hydrolysis by pepsin and trypsinase on quality and molecular weight distribution of hyaluronic acid extracted from rooster comb were studied. The optimal hydrolytic conditions were obtained as follows: enzymatic hydrolysis peroid 2 h, dosage of pepsin 30 g/kg and trypsinase 3 g/kg, pH of trypsinase solution 8.5 and temperature 45 "C, respectively. The yield of hyaluronic acid was 0.5 % - 0.6% and the content of glucuronic acid was 41.2% - 44.3%. The average molecular weight of hyaluronic acid was over l.OxlO6 and the molecular weight distribution exponent was about 1.

  3. Bagasse hydrolyzates from Agave tequilana as substrates for succinic acid production by Actinobacillus succinogenes in batch and repeated batch reactor.

    Corona-González, Rosa Isela; Varela-Almanza, Karla María; Arriola-Guevara, Enrique; Martínez-Gómez, Álvaro de Jesús; Pelayo-Ortiz, Carlos; Toriz, Guillermo

    2016-04-01

    The aim of this work was to obtain fermentable sugars by enzymatic or acid hydrolyses of Agave tequilana Weber bagasse in order to produce succinic acid with Actinobacillus succinogenes. Hydrolyses were carried out with mineral acids (sulfuric and hydrochloric acids) or a commercial cellulolytic enzyme, and were optimized statistically by a response surface methodology, having as factors the concentration of acid/enzyme and time of hydrolysis. The concentration of sugars obtained at optimal conditions for each hydrolysis were 21.7, 22.4y 19.8g/L for H2SO4, HCl and the enzymatic preparation respectively. Concerning succinic acid production, the enzymatic hydrolyzates resulted in the highest yield (0.446g/g) and productivity (0.57g/Lh) using A. succinogenes in a batch reactor system. Repeated batch fermentation with immobilized A. succinogenes in agar and with the enzymatic hydrolyzates resulted in a maximum concentration of succinic acid of 33.6g/L from 87.2g/L monosaccharides after 5 cycles in 40h, obtaining a productivity of 1.32g/Lh. PMID:26802183

  4. Phytate hydrolysis by germfree and conventional rats.

    Wise, A; Gilburt, D J

    1982-01-01

    Phytic acid is naturally occurring compound that reduces intestinal absorption of many metals. Early work suggests that some dietary phytate may be hydrolyzed in the large intestines by bacteria, but more recently nutritionists have suggested that a mucosal enzyme is responsible. This paper reports a study intended to resolve this controversy. The hydrolysis of dietary phytic acid was measured in germfree and conventional rats fed either of two diets that differed in their calcium content. Ne...

  5. Determination of scandium in geological materials, rare earth minerals and niobate/tantalate-type of samples by inductively coupled plasma atomic emission spectrometry after solvent extraction/acid hydrolysis separation

    Solvent extraction of scandium from 1.5 M HCl medium using di(2-ethyl hexyl) phosphoric acid in hexane or benzene selectively separates Sc from the accompanying elements in rare-earth minerals (like monazite, xenotime, gadolinite) and also in geological materials. Acid hydrolysis separation of Nb/Ta-type samples separates Sc from the major matrix elements and the remaining elements do not influence the Sc signal in inductively coupled plasma atomic emission spectrometry or flame atomic absorption spectrometry. To avoid the matrix effect due to sodium that accompanies the analyte using the reported backstripping of Sc from the organic extract by 2 M NaOH, the organic extract was evaporated off leaving the Sc in the residue which in turn was treated with a mixture of HNO3-HClO4, dissolved in HCl (10%, v/v) and made up to a known volume before aspiration in the plasma for estimation. The silica-rich geological materials were dissolved by HF-HCl-H2SO4 treatment and the rare-earth minerals (monazite/xenotime) were digested by H2SO4-HCl followed by dissolution in 1.5 M HCl before applying the solvent extraction procedure. In Nb/Ta-type of samples, Sc was separated from Nb and Ta by acid hydrolysis, involving fusion with Na2O2, dissolution in HCl followed by NH3 precipitation and hydrolysis in HCl. The oxychloride precipitates of Nb and Ta are filtered off and the filtrates assayed for Sc. The proposed methods have been applied to some international geological reference standards (SY-2, SY-3, MRG-1, Mica-Fe, G-2, GH and ASK-2), rare-earth minerals like monazite, xenotime and gadolinite and also to some Nb/Ta-type samples including reference standards IGS-33 and IGS-34, and the results are compared. Both methods are simple, rapid and accurate, showing a relative standard deviation of less than 1% at the 55 μg g-1 level and 9.0% (at the 1.0 μg g-1). (Copyright (c) 1998 Elsevier Science B.V., Amsterdam. All rights reserved.)

  6. Enzymatic Hydrolysis of Lignocelluloses

    Kolasa, Marta; Ahring, Birgitte Kiær; Lübeck, Peter Stephensen;

    2010-01-01

    bonds. Cellulose can be degraded to simple sugar components by means of enzymatic hydrolysis. However, due to its complex, crystalline structure it is difficult to break it down and the cooperative action of a variety of cellulolytic enzymes is necessary. Fungi are known to have potential in production...... of a variety of cellulolytic enzymes. The aim of this work is to discover new thermostable and robust cellulolytic enzymes for improved enzymatic hydrolysis of biomass. For this purpose two screening methods are applied in different fungal strains with high cellulolytic activities: an expression...

  7. Theoretical studies of binding of mannose-binding protein to monosaccharides

    Aida-Hyugaji, Sachiko; Takano, Keiko; Takada, Toshikazu; Hosoya, Haruo; Kojima, Naoya; Mizuochi, Tsuguo; Inoue, Yasushi

    2004-11-01

    Binding properties of mannose-binding protein (MBP) to monosaccharides are discussed based on ab initio molecular orbital calculations for cluster models constructed. The calculated binding energies indicate that MBP has an affinity for N-acetyl- D-glucosamine, D-mannose, L-fucose, and D-glucose rather than D-galactose and N-acetyl- D-galactosamine, which is consistent with the biochemical experimental results. Electrostatic potential surfaces at the binding site of four monosaccharides having binding properties matched well with that of MBP. A vacant frontier orbital was found to be localized around the binding site of MBP, suggesting that MBP-monosaccharide interaction may occur through electrostatic and orbital interactions.

  8. Analysis of myo-inositol hexakisphosphate hydrolysis by Bacillus phytase

    Kerovuo, J.; Rouvinen, J.; Hatzack, Frank-Andreas

    2000-01-01

    Phytic acid (myo-inositol hexakisphosphate, InsP(6)) hydrolysis by Bacillus phytase (PhyC) was studied. The enzyme hydrolyses only three phosphates from phytic acid. Moreover, the enzyme seems to prefer the hydrolysis of every second phosphate over that of adjacent ones. Furthermore, it is very...... likely that the enzyme has two alternative pathways for the hydrolysis of phytic acid, resulting in two different myo-inositol trisphosphate end products: Ins(2,4,6)P-8 and Ins(1,3,5)P-3. These results, together with inhibition studies with fluoride, vanadate, substrate and a substrate analogue, indicate......) computer-modelling analyses of enzyme-substrate complexes, a novel mode of phytic acid hydrolysis is proposed....

  9. Monosaccharide profiling of silkworm (Bombyx mori L.) nervous system during development and aging.

    Soya, Seçkin; Şahar, Umut; Karaçalı, Sabire

    2016-09-01

    Glycoconjugates have various functions in differentiation, development, aging and in all aspects of normal functioning of organisms. The reason for increased research on this topic is that glycoconjugates locate mostly on the cell surface and play crucial biological roles in the nervous system including brain development, synaptic plasticity, learning, and memory. Considering their roles in the nervous system, information about their existence in the insect nervous system is rather sparse. Therefore, in order to detect monosaccharide content of N- and O-glycans, we carried out capLC-ESI-MS/MS analysis to determine the concentration changes of glucose, mannose, galactose, N-acetylglucosamine (GlcNAc), N-acetylgalactosamine (GalNAc), fucose, xylose, arabinose, and ribose monosaccharides in the nervous system of Bombyx mori during development and aging processes. In addition to LC-MS, lectin blotting was done to detect quantitative changes in N- and O-glycans. Developmental stages were selected as 3rd (the youngest sample), 5th (young) larval instar, motionless prepupa (the oldest sample), and pupa (adult development). Derivatization of monosaccharides was performed with a solution of PMP agent and analyzed with capLC-ESI-MS/MS. For lectin blotting, determination of glycan types was carried out with Galanthus nivalis agglutinin and Peanut agglutinin lectins. In all stages, the most abundant monosaccharide was glucose. Although all monosaccharides were present most abundantly in the youngest stage (3rd instar), they are generally reduced gradually during the aging process. It was observed that amounts of monosaccharides increased again in the pupa stage. According to lectin blotting, N- and O-linked glycoproteins expressions were different and there were some specific glycoprotein expression differences between stages. These findings suggest that the glycosylation state of proteins in the nervous system changes during development and aging in insects in a similar

  10. Enzymatic hydrolysis of pretreated soybean straw

    In order to produce lactic acid, from agricultural residues such as soybean straw, which is a raw material for biodegradable plastic production, it is necessary to decompose the soybean straw into soluble sugars. Enzymatic hydrolysis is one of the methods in common use, while pretreatment is the effective way to increase the hydrolysis rate. The optimal conditions of pretreatment using ammonia and enzymatic hydrolysis of soybean straw were determined. Compared with the untreated straw, cellulose in straw pretreated by ammonia liquor (10%) soaking for 24 h at room temperature increased 70.27%, whereas hemicellulose and lignin in pretreated straw decreased to 41.45% and 30.16%, respectively. The results of infrared spectra (IR), scanning electron microscope (SEM) and X-ray diffraction (XRD) analysis also showed that the structure and the surface of the straw were changed through pretreatment that is in favor of the following enzymatic hydrolysis. maximum enzymatic hydrolysis rate of 51.22% was achieved at a substrate concentration of 5% (w/v) at 50 deg. C and pH 4.8 using cellulase (50 fpu/g of substrate) for 36 h

  11. Accelerated hydrolysis of substituted cellulose for potential biofuel production: kinetic study and modeling.

    Mu, Bingnan; Xu, Helan; Yang, Yiqi

    2015-11-01

    In this work, kinetics of substitution accelerated cellulose hydrolysis with multiple reaction stages was investigated to lay foundation for mechanism study and molecular design of substituting compounds. High-efficiency hydrolysis of cellulose is critical for cellulose-based bioethanol production. It is known that, substitution could substantially decrease activation energy and increase reaction rate of acidic hydrolysis of glycosidic bonds in cellulose. However, reaction kinetics and mechanism of the accelerated hydrolysis were not fully revealed. In this research, it was proved that substitution therefore accelerated hydrolysis only occurred in amorphous regions of cellulose fibers, and was a process with multiple reaction stages. With molar ratio of substitution less than 1%, the overall hydrolysis rate could be increased for around 10 times. We also quantified the relationship between the hydrolysis rate of individual reaction stage and its major influences, including molar ratio of substitution, activation energy of acidic hydrolysis, pH and temperature. PMID:26253917

  12. Acid Hydrolysis of Wheat Gluten Induces Formation of New Epitopes but Does Not Enhance Sensitizing Capacity by the Oral Route: A Study in “Gluten Free” Brown Norway Rats

    Kroghsbo, Stine; Andersen, Nanna Birch; Rasmussen, Tina Frid;

    2014-01-01

    sensitizing capacity of gluten proteins per se when altered by acid or enzymatic hydrolysis relative to unmodified gluten in rats naïve to gluten. Methods High IgE-responder Brown Norway (BN) rats bred on a gluten-free diet were sensitized without the use of adjuvant to three different gluten products...... (unmodified, acid hydrolyzed and enzymatic hydrolyzed). Rats were sensitized by intraperitoneal (i.p.) immunization three times with 200 µg gluten protein/rat or by oral dosing for 35 days with 0.2, 2 or 20 mg gluten protein/rat/day. Sera were analyzed for specific IgG and IgE and IgG-binding capacity by...... ELISA. IgE functionality was measured by rat basophilic leukemia (RBL) assay. Results Regardless of the route of dosing, all products had sensitizing capacity. When sensitized i.p., all three gluten products induced a strong IgG1 response in all animals. Acid hydrolyzed gluten induced the highest level...

  13. pH对油酸水解废水酸化发酵过程的影响%Effect of pH on the Acidification Fermentation Process in Oleic Acid Hydrolysis Wastewater

    吴九九; 刘建平; 杨春燕

    2012-01-01

    pH对油酸水解废水酸化发酵影响的研究表明,pH不仅对酸化速率有很大影响,而且也会影响酸化产物的构成;不同pH值下酸化的主要产物是乙酸,但酸化的最佳pH值为6.5,此pH条件下VFA的产量最高可达12.53 g/L;在pH〉7时,明显有丙酸生成。%The impact of pH on the environment of acidification fermentation in oleic acid hydrolysis wastewater is studied, and the results show that pH has a great influence not only on the rate of acidi- fication ,but also on the composition of acidification products. The chief product of acidification is acetic acid under different pH value. The most favorable pH value in acidification is 6.5, at which the highest yielding of VFA ( 12.53 g/L) was obtained. The formation of propionic acid is apparent when pH 〉 7.

  14. NREL 2012 Achievement of Ethanol Cost Targets: Biochemical Ethanol Fermentation via Dilute-Acid Pretreatment and Enzymatic Hydrolysis of Corn Stover

    Tao, L.; Schell, D.; Davis, R.; Tan, E.; Elander, R.; Bratis, A.

    2014-04-01

    For the DOE Bioenergy Technologies Office, the annual State of Technology (SOT) assessment is an essential activity for quantifying the benefits of biochemical platform research. This assessment has historically allowed the impact of research progress achieved through targeted Bioenergy Technologies Office funding to be quantified in terms of economic improvements within the context of a fully integrated cellulosic ethanol production process. As such, progress toward the ultimate 2012 goal of demonstrating cost-competitive cellulosic ethanol technology can be tracked. With an assumed feedstock cost for corn stover of $58.50/ton this target has historically been set at $1.41/gal ethanol for conversion costs only (exclusive of feedstock) and $2.15/gal total production cost (inclusive of feedstock) or minimum ethanol selling price (MESP). This year, fully integrated cellulosic ethanol production data generated by National Renewable Energy Laboratory (NREL) researchers in their Integrated Biorefinery Research Facility (IBRF) successfully demonstrated performance commensurate with both the FY 2012 SOT MESP target of $2.15/gal (2007$, $58.50/ton feedstock cost) and the conversion target of $1.41/gal through core research and process improvements in pretreatment, enzymatic hydrolysis, and fermentation.

  15. Glycosaminoglycan Monosaccharide Blocks Analysis by Quantum Mechanics, Molecular Dynamics, and Nuclear Magnetic Resonance

    Sergey A. Samsonov

    2014-01-01

    Full Text Available Glycosaminoglycans (GAGs play an important role in many biological processes in the extracellular matrix. In a theoretical approach, structures of monosaccharide building blocks of natural GAGs and their sulfated derivatives were optimized by a B3LYP6311ppdd//B3LYP/6-31+G(d method. The dependence of the observed conformational properties on the applied methodology is described. NMR chemical shifts and proton-proton spin-spin coupling constants were calculated using the GIAO approach and analyzed in terms of the method's accuracy and sensitivity towards the influence of sulfation, O1-methylation, conformations of sugar ring, and ω dihedral angle. The net sulfation of the monosaccharides was found to be correlated with the 1H chemical shifts in the methyl group of the N-acetylated saccharides both theoretically and experimentally. The ω dihedral angle conformation populations of free monosaccharides and monosaccharide blocks within polymeric GAG molecules were calculated by a molecular dynamics approach using the GLYCAM06 force field and compared with the available NMR and quantum mechanical data. Qualitative trends for the impact of sulfation and ring conformation on the chemical shifts and proton-proton spin-spin coupling constants were obtained and discussed in terms of the potential and limitations of the computational methodology used to be complementary to NMR experiments and to assist in experimental data assignment.

  16. Monosaccharide-responsive phenylboronate-polyol cell scaffolds for cell sheet and tissue engineering applications.

    Rachamalla Maheedhar Reddy

    Full Text Available Analyte-responsive smart polymeric materials are of great interest and have been actively investigated in the field of regenerative medicine. Phenylboronate containing copolymers form gels with polyols under alkaline conditions. Monosaccharides, by virtue of their higher affinity towards boronate, can displace polyols and solubilize such gels. In the present study, we investigate the possibility of utilizing phenylboronate-polyol interactions at physiological pH in order to develop monosaccharide-responsive degradable scaffold materials for systems dealing with cells and tissues. Amine assisted phenylboronate-polyol interactions were employed to develop novel hydrogel and cryogel scaffolds at neutral pH. The scaffolds displayed monosaccharide inducible gel-sol phase transformability. In vitro cell culture studies demonstrated the ability of scaffolds to support cell adhesion, viability and proliferation. Fructose induced gel degradation is used to recover cells cultured on the hydrogels. The cryogels displayed open macroporous structure and superior mechanical properties. These novel phase transformable phenylboronate-polyol based scaffolds displayed a great potential for various cell sheet and tissue engineering applications. Their monosaccharide responsiveness at physiological pH is very useful and can be utilized in the fields of cell immobilization, spheroid culture, saccharide recognition and analyte-responsive drug delivery.

  17. Hydrolysis of Cellulose by a Mesoporous Carbon-Fe2(SO4)3/γ-Fe2O3 Nanoparticle-Based Solid Acid Catalyst

    Daizo Yamaguchi; Koki Watanabe; Shinya Fukumi

    2016-01-01

    Carbon-based solid acid catalysts have shown significant potential in a wide range of applications, and they have been successfully synthesized using simple processes. Magnetically separable mesoporous carbon composites also have enormous potential, especially in separation and adsorption technology. However, existing techniques have been unable to produce a magnetically separable mesoporous solid acid catalyst because no suitable precursors have been identified. Herein we describe a magnetic...

  18. Utilization of fisheries by-catch and processing wastes for lactic acid fermented silage and evaluation of degree of protein hydrolysis and in vitro digestibility

    J. C. Ramírez- Ramírez; Huerta, S; Arias, L.; Prado, A.; Shirai, K.

    2008-01-01

    The purpose of this study was to produce protein hydrolysates from lactic acid fermentation of three sources of fish wastes: Shrimp by catch (SC), Sphyraena ensis wastes (SB) and mixture of fisheries processing wastes from several species (MixW). MixW were added with several sugar cane molasses concentrations as the carbon source, 180 g.kg-1 of sugar molasses gave the fastest acidification. The maximum concentration of lactic acid (Pmax) was significantly higher with Lactobacillus sp. B2 than...

  19. Effect of different monosaccharides and disaccharides on boar sperm quality after cryopreservation.

    Gómez-Fernández, José; Gómez-Izquierdo, Emilio; Tomás, Cristina; Mocé, Eva; de Mercado, Eduardo

    2012-07-01

    The aim of the present study was to evaluate the cryoprotectant effect of different non-permeating sugars for boar sperm. Pooled semen from three boars was used for the experiments. In the first experiment, the sperm quality of boar sperm cryopreserved with an egg-yolk based extender supplemented with different monosaccharides (glucose, galactose or fructose) was compared to a control cryopreserved in lactose-egg yolk extender. In the second experiment, the effect of five disaccharides (lactose, sucrose, lactulose, trehalose or melibiose) on boar sperm cryosurvival was studied. Several sperm quality parameters were assessed by flow cytometry in samples incubated for 30 and 150 min at 37°C after thawing: percentages of sperm with intact plasma membrane (SIPM), sperm presenting high plasma membrane fluidity (HPMF), sperm with intracellular reactive oxygen substances production (IROSP) and apoptotic sperm (AS). In addition, the percentages of total motile (TMS) and progressively motile sperm (PMS) were assessed at the same incubation times with a computer-assisted sperm analysis system. Freezing extenders supplemented with each of the monosaccharide presented smaller cryoprotective effect than the control extender supplemented with lactose (P<0.05). However, from the three monosaccharides tested, glucose provided the best sperm quality after freezing-thawing. With respect to the disaccharides studied, samples frozen with the extender supplemented with lactulose exhibited in general the lowest sperm quality, except for the percentage of capacitated sperm, which was highest (P<0.05) in the samples cryopreserved with the trehalose extender. Our results suggest that disaccharides have higher cryoprotective effect than monosaccharides, although the monosaccharide composition of the disaccharides is also important, since the best results were obtained with those disaccharides presenting glucose in their composition. PMID:22771077

  20. Production of Ricinoleic Acid from Castor Oil by Free Lipase-mediated Hydrolysis%游离脂肪酶催化蓖麻油制备蓖麻油酸

    杨威; 杜伟; 刘德华

    2014-01-01

    游离脂肪酶与固定化脂肪酶相比具有成本低、反应速率快等优势,是油脂化工中新的研究方向。前期研究表明,游离脂肪酶NS81006能高效催化多种油脂水解,进一步研究其对含独特羟基的绿色石油材料蓖麻油的水解过程,对于促进游离脂肪酶在新能源领域的应用具有重要意义。本文对影响游离脂肪酶NS81006催化蓖麻油水解过程的主要因素,温度、酶用量、水用量和搅拌速率进行了研究和优化,在优化后的条件下48 h水解率可达94.8%,且发现通过离心分离可有效实现NS81006的重复使用,连续回用5个批次,游离脂肪酶仍能有效催化水解反应。而对比高温高压法水解蓖麻油,发现游离脂肪酶NS81006具有明显优势。%Compared to immobilized lipase, free lipase has the merits of lower cost and faster reaction rate, which is a rising research orientation in oil chemical industry. The previous study showed that free lipase NS81006 is capable of efficiently hydrolyzing oil to fatty acids. Further study on its unique hydrolysis process of castor oil, an environmentally friendly hydroxyl oil, is of great importance for its application in new energy. By means of optimizing the main influence factors of the castor oil hydrolysis catalyzed by NS81006 involving temperature, enzyme dosage, water usage, and stirring speed, 98. 4% degree of hydrolysis was achieved under the optimum conditions at 48 h. The free lipase could be reused after centrifugation and maintained high catalytic efficiency in 5 consecutive recovery batches. It was also found that enzyme catalysis has obvious advantage in castor oil hydrolyzation compared with HTHP .

  1. Bis-Indole Derivatives for Polysaccharide Compositional Analysis and Chiral Resolution of D-, L-Monosaccharides by Ligand Exchange Capillary Electrophoresis Using Borate-Cyclodextrin as a Chiral Selector

    Wen-Bin Yang; Yin-Chen Liu; Kuo-Shiang Liao; Chien-Yuan Kuo

    2011-01-01

    A series of aldo-bis-indole derivatives (aldo-BINs) was prepared by aromatic C-alkylation reactions of aldoses and indole in acetic acid solution. Common monosaccharides such as glucose, mannose, galactose, fucose, xylose, rhamnose, ribose, arabinose and N-acetylglucosamine were smoothly derivatized to form the UV absorbing aldo-BINs. The use of a capillary electrophoretic method to separate these novel aldo-BIN derivatives was established. The capillary electrophoresis conditions were set by...

  2. 半纤维素稀酸循环喷淋冲滤水解动力学%Kinetics of hemicellulose hydrolysis by dilute acid with cycle spray flow-through

    金强; 张红漫; 徐锐; 林增祥; 郑荣平; 赵晶

    2011-01-01

    采用稀酸循环喷淋冲滤(dilute acid cycle spray flow-through,DCF)反应器在温和的条件下水解玉米秸秆半纤维素,分析了半纤维素稀酸水解产物组分,研究不同温度、硫酸浓度和时间对主要产物木糖浓度的影响.探讨了其水解反应机理并以酸催化反应机理为基础,把玉米秸秆半纤维素及其水解产物按化学组成和性质进行集总划分,并对反应网络进行合理简化,提出了一种半纤维素稀酸水解反应的简化集总动力学模型.通过参数估计求取动力学参数,建立集总动力学模型以预测半纤维素主要水解产物.结果表明,喷淋作用加快了半纤维素的连续解聚过程,从而使得木糖得率超过90%,而其降解产物糠醛等较少.得到的模型能较好预测不同条件下主要产物含量.通过改进的Arrhenius方程确定木糖生成和降解的活化能分别为107.1 kJ·mol-1和102.2 kJ·mol-1.%Hemicellulose hydrolysis of corn stover catalyzed dilute acid was conducted at mild conditions in a reactor with cycle spray flow-through (DCF). The hydrolysate was analyzed and the effect of temperature, sulfuric acid concentration and reaction time on the concentration of main product xylose was studied. The results show that cycle spray can speed effectively up the process for continuos depolymerization of hemicellulose, and make the yield of xylose over 90% and less degradation products such as furaldehyde. Based on the acid catalyzed reaction mechanism of hemicellulose hydrolysis,hemicellulose and their hydrolysates were classified and lumped by their chemical composition and property, and a lumped kinetic model was proposed on reasonable simplification of reaction network. The kinetic rate constants were obtained by parameters estimation. The lumped kinetic model established can be used to predict the major hydrolysates and their contents at various hydrolysis conditions. The activation energy of xylose formation and degradation

  3. Comparative study on chemical pretreatments to accelerate enzymatic hydrolysis of aquatic macrophyte biomass used in water purification processes.

    Mishima, D; Tateda, M; Ike, M; Fujita, M

    2006-11-01

    In this study, enzymatic hydrolysis of two floating aquatic plants which are suitable for water purification, water hyacinth (Eichhornia crassipes) and water lettuce (Pistia stratiotes L.), was performed to produce sugars. Twenty chemical pretreatments were comparatively examined in order to improve the efficiency of enzymatic hydrolysis. As a result, the alkaline/oxidative (A/O) pretreatment, in which sodium hydroxide and hydrogen peroxide were used, was the most effective pretreatment in terms of improving enzymatic hydrolysis of the leaves of water hyacinth and water lettuce. The amount of reducing sugars in enzymatic hydrolysate of water lettuce leaves was 1.8 times higher than that of water hyacinth leaves, therefore water lettuce seems to be more attractive as a biomass resource than water hyacinth. Although roots of these plants contained large amounts of polysaccharides such as cellulose and hemicellulose, they generated less monosaccharides than from leaves, no matter which chemical pretreatment was tested. PMID:16309902

  4. The optimization of soybean oil hydrolysis reaction research

    The hydrolysis reaction of soybean oil was optimized. The concentration effect of ethanolic alkaline solution (KOH and NaOH) to the oil acidity was studied. The alkaline concentrations, reaction time and temperature factors was investigated during the optimization of the hydrolysis or saponification reaction. KOH solution of 1 M showed a good saponification activity which resulted oil acid value of 226.8 mg/ g compared to NaOH solution with acid value of 225.4 mg/ g for the same reaction. The optimum saponification reaction of soybean oil occurred at 60 degree Celsius in 30 minutes by using ethanolic KOH 1 M with acid value of 229.6 mg/ g. Composition of free fatty acid before and after hydrolysis were determined by using gas chromatography. (author)

  5. PLA recycling by hydrolysis at high temperature

    Cristina, Annesini Maria; Rosaria, Augelletti; Sara, Frattari; Fausto, Gironi

    2016-05-01

    In this work the process of PLA hydrolysis at high temperature was studied, in order to evaluate the possibility of chemical recycling of this polymer bio-based. In particular, the possibility to obtain the monomer of lactic acid from PLA degradation was investigated. The results of some preliminary tests, performed in a laboratory batch reactor at high temperature, are presented: the experimental results show that the complete degradation of PLA can be obtained in relatively low reaction times.

  6. Development of complete hydrolysis of pectins from apple pomace.

    Wikiera, Agnieszka; Mika, Magdalena; Starzyńska-Janiszewska, Anna; Stodolak, Bożena

    2015-04-01

    Enzymatically extracted pectins have a more complex structure than those obtained by conventional methods. As a result, they are less susceptible to hydrolysis, which makes the precise determination of their composition difficult. The aim of the study was to develop a method of complete hydrolysis of enzymatically extracted apple pectins. Substrates were pectins isolated from apple pomace by the use of xylanase and multicatalytic preparation Celluclast and apple pomace. Hydrolysis was performed by a chemical method with 2M TFA at 100 °C and 120 °C and a combined acidic/enzymatic method. After hydrolysis, the contents of galacturonic acid and neutral sugars were measured by HPLC. Complete hydrolysis of polygalacturonic acid occurred after 2.5h incubation with 2M TFA at 120 °C. The efficient hydrolysis of neutral sugars in pectins was performed with 2M TFA at 100 °C for 2.5h. Monomers most susceptible to concentrated acid were rhamnose, mannose and arabinose. PMID:25442606

  7. Enzymatic hydrolysis of steryl glycosides for their analysis in foods.

    Münger, Linda H; Nyström, Laura

    2014-11-15

    Steryl glycosides (SG) contribute significantly to the total intake of phytosterols. The standard analytical procedure involving acid hydrolysis fails to reflect the correct sterol profile of SG due to isomerization of some of the labile sterols. Therefore, various glycosylases were evaluated for their ability to hydrolyse SG under milder conditions. Using a pure SG mixture in aqueous solution, the highest glycolytic activity, as demonstrated by the decrease in SG and increase in free sterols was achieved using inulinase preparations (decrease of >95%). High glycolytic activity was also demonstrated using hemicellulase (63%). The applicability of enzymatic hydrolysis using inulinase preparations was further verified on SG extracted from foods. For example in potato peel Δ(5)-avenasteryl glucoside, a labile SG, was well preserved and contributed 26.9% of the total SG. Therefore, enzymatic hydrolysis is suitable for replacing acid hydrolysis of SG in food lipid extracts to accurately determine the sterol profile of SG. PMID:24912717

  8. Hydrolysis of green tea residue protein using proteolytic enzyme derived from Aspergillus oryzae

    Xu, Yong-Quan; Zhong, Xiao-Yu; Chen, Su-Qin; Yin, Jun-Feng

    2011-01-01

    Free amino acids are important chemical components which impact the taste of green tea infusion. The hydrolysis of water-insoluble protein in the green tea residue helps to increase the contents of free amino acids components except theanine. Studies indicate that the hydrolysis of the tea protein could be restricted due to interaction of polyphenols with protein. The experiment indicates that the hydrolysis of tea protein by protease is the main trend when the polyphenols concentration is lo...

  9. Analysis of Monosaccharide Composition of Pu-erh Tea Polysaccaride by Pre-column Derivatization HPLC%柱前衍生HPLC法分析普洱茶多糖中单糖组成

    郭威; 周斌星; 罗玲; 李扬; 柴洁; 杨超; 马存强

    2013-01-01

    [Objective] This study aimed to establish a pre-column derivatization HPLC method for the identification and analysis of monosaccharide composition of Pu-erh tea polysaccharide.[Method] Pu-erh tea polysaccharide was extracted using the water extraction method,further isolated and purified by DEAE cellulose-52 columns.The obtained tea polysaccharide and four components TPS1,TPS2,TPS3 and TPS4 were first derived by 1-phenyl-3-methyl-5-pyrazolone (PMP),and then the PMP derivatives of monosaccharide were analyzed by high performance liquid chromatography (HPLC).[Result] Pu-erh tea polysaccharide contained eight kinds of monosac-charides (mannose,rhamnose,glucuronic acid,galacturonic acid,glucose,galactose,arabinose,fucose),without xylose; so it was the same with TPS1; each of TPS2,TPS3 and TPS4 contained seven monosaccharides,while no fucose.[Conclusion]This method is simplified and rapid,which can be used to determine the monosac-charide composition of Pu-erh tea polysaccharide and monosaccharide content.%[目的]建立柱前衍生HPLC法鉴别和分析普洱茶多糖中单糖组成.[方法]采用水提法提取普洱茶多糖,经DEAE Cellulose-52纤维素柱分离纯化;茶多糖及其组分TPS1、TPS2、TPS3、TPS4经1-苯基-3-甲基-5-吡唑啉酮(PMP)衍生化后,利用高效液相色谱法,分析单糖的PMP衍生物.[结果]普洱茶多糖中含有甘露糖、鼠李糖、葡萄糖醛酸、半乳糖醛酸、葡萄糖、半乳糖、阿拉伯糖、岩藻糖8种单糖,不含有木糖;TPS1中含有全部8种单糖;TPS2、TPS3和TPS4均由7种单糖组成,且都不含岩藻糖.[结论]此方法简便,快速;可用于测定普洱茶多糖中单糖的组成分析和含量测定.

  10. SIMULTANEOUS PRETREATMENT OF LIGNOCELLULOSE AND HYDROLYSIS OF STARCH IN MIXTURES TO SUGARS

    Hamzeh Hoseinpour

    2010-11-01

    Full Text Available Mixtures of starch and lignocelluloses are available in many industrial, agricultural, and municipal wastes and residuals. In this work, dilute sulfuric acid was used for simultaneous pretreatment of lignocellulose and hydrolysis of starch, to obtain a maximum amount of fermentable sugar after enzymatic hydrolysis with cellulase and β-glucosidase. The acid treatment was carried out at 70-150°C with 0-1% (v/v acid concentration and 5-15% (w/v solids concentration for 0-40 minutes. Under the optimum conditions, obtained at 130°C, 1% acid, and 7.5% solids loading for 30 min, the starch was almost completely converted to glucose. However, the acid treatment was not successful for efficient hydrolysis of pure cellulose. A mixture of pine softwood and potato as representatives of lignocellulosic and starch components, respectively, were treated at the optimum conditions for acid hydrolysis of starch. The dilute-acid treatment resulted in 1.2, 60.5, and 23.6% hydrolysis of glucan, xylan, and mannan of pine wood and 67% of potato starch to fermentable sugars. After the acid treatment, the solid residue of the mixture was subjected to enzymatic hydrolysis. The enzymatic hydrolysis under the optimum conditions resulted in conversion of 76% of the glucan in the treated softwood. Therefore, using acid treatment of the mixture is a promising process for pretreatment of wood in addition to the hydrolysis of starch.

  11. Hydrolysis of lithium hydride

    Due to its high hydrogen density and unique nuclear chemistry, lithium hydride, in all its isotopic forms, has an unsurpassed place in modem nuclear weapons. The hydrolysis of the material, and the outgassing of hydrogen from the bulk, are crucial to the performance of the material in service. This thesis describes research conducted at AWE Aldermaston, UK, to examine the hydrolysis and hydrogen outgassing from the bulk material, with the aim of ultimately developing the kinetics 8c mechanisms responsible. The basic chemistry is of great interest, especially the reaction with water. This reaction, whilst being fairly extensively studied in the past, has not been conclusively described with an accepted mechanism and associated kinetics. The last significant UK work on the topic was by Imperial College, London, under contract to AW(R)E in the late 1960s. This thesis describes the development of: (i) a solid state NMR spectroscopy technique to examine semi-quantitatively the surface of bulk lithium hydride for its chemical composition, and (ii) a dedicated lithium hydride inert atmosphere gravimetric analysis glove box to study the hydride/water reaction. Solid State NMR Spectroscopy has been utilised for the first time to probe the hydride/hydroxide ratio of partially hydrolysed lithium hydride. 6Li chemical shifts have been established for species of interest and extremely long, up to 17 hours, T1 relaxation times have been measured for 6Li hydride and hydroxide. A method for semi-quantitatively determining the hydroxide/hydride composition of a partially reacted sample has been developed, based on a 'dual-scan' technique using one short and one long pulse sequence. Gravimetric analysis has been developed for lithium hydride/humidity studies. This facility fully contains gravimetric analysis within an argon glove box, with the ability to control the sample atmosphere from room temperature to 60 deg C and from 0.5 to 40 percent relative humidity. The hydrolysis of

  12. Hydrolysis of Bioactive Isoflavone in Soymilk Fermented with β-glucosidase Producing Lactic Acid Bacteria From Local Fermented Foods of Indonesian

    Sumarna

    2010-01-01

    This study investigated the possible application of β-glucosidase producing lactic acid bacteria isolated from local fermented foods as a functional starter culture to obtain the bioactive isoflavones, genistein and daidzein, in fermented soymilk. Seven strains of bacteria, Lactobacillus plantarum pentosus SMN 001, Lactobacillus casei subsp rhamnosus FNCC 098, Lactobacillus casei subsp rhamnosus FNCC 099, Lactobacillus casei subsp rhamnosus FNCC 113, Lactobacillus delbrueckii subsp. del...

  13. Enzymatic hydrolysis of cuttlefish (Sepia officinalis) and sardine (Sardina pilchardus) viscera using commercial proteases: Effects on lipid distribution and amino acid composition

    Kechaou, Emna; Durnay, Justine; Donnay-Moreno, Claire; Jaouen, Pascal; Gouygou, Jean-paul; Berge, Jean-pascal; Ben Arnar, Raja

    2009-01-01

    Total lipid and phospholipid recovery as well as amino acid quality and composition from cuttlefish (Sepia officinalis) and sardine (Sardina pilchardus) were compared. Enzymatic hydrolyses were performed using the three proteases Protamex, Alcalase, and Flavourzyme by the pH-stat method (24 h, pH 8, 50 degrees C). Three fractions were generated: an insoluble sludge, a soluble aqueous phase, and an oily phase. For each fraction, lipids, phospholipids, and proteins were quantified. Quantitative...

  14. Process Design Report for Wood Feedstock: Lignocellulosic Biomass to Ethanol Process Desing and Economics Utilizing Co-Current Dilute Acid Prehydrolysis and Enzymatic Hydrolysis Current and Futuristic Scenarios

    Wooley, Robert [National Renewable Energy Lab. (NREL), Golden, CO (United States); Ruth, Mark [National Renewable Energy Lab. (NREL), Golden, CO (United States); Sheehan, John [National Renewable Energy Lab. (NREL), Golden, CO (United States); Ibsen, Kelly [National Renewable Energy Lab. (NREL), Golden, CO (United States); Majdeski, Henry [Delta-T Corporation, Lexington, KY (United States); Galves, Adrian [Delta-T Corporation, Lexington, KY (United States)

    1999-07-01

    The National Renewable Energy Laboratory (NREL) has undertaken a complete review and update of the process design and economic model for the biomass-to-ethanol process based on co-current dilute acid prehydrolysis, along with simultaneous saccharification (enzymatic) and co-fermentation. The process design includes the core technologies being researched by the U.S. Department of Energy (DOE): prehydrolysis, simultaneous saccharification and co-fermentation, and cellulase enzyme production.

  15. Hydrolysis of starch by sorghum malt for maltodextrin production [abstract

    Thonart, P.; Destain, J.; Ba, K.

    2010-01-01

    Maltodextrin is a mixture of saccharides with a molecular weight between polysaccharides and oligosaccharides with DE lower than 20. Maltodextrin is more soluble in water than native starches, also is cheaper in comparison with other major edible hydrocolloids. Maltodextrin is obtained by moderate enzymatic or acidic hydrolysis of starch. The hydrolysis of starch, catalyzed by amylases, is the most important commercial enzyme process. The hydrolyzed products are widely applied in food, paper ...

  16. Hydrolysis of starch by sorghum malt for maltodextrin production

    Ba, K.; Destain, Jacqueline; Thonart, Philippe

    2010-01-01

    Maltodextrin is a mixture of saccharides with a molecular weight between polysaccharides and oligosaccharides with DE lower than 20. Maltodextrin is more soluble in water than native starches, also is cheaper in comparison with other major edible hydrocolloids. Maltodextrin is obtained by moderate enzymatic or acidic hydrolysis of starch. The hydrolysis of starch, catalyzed by amylases, is the most important commercial enzyme process. The hydrolyzed products are widely applied in food, paper ...

  17. Hydrolysis of Bioactive Isoflavone in Soymilk Fermented with β-glucosidase Producing Lactic Acid Bacteria From Local Fermented Foods of Indonesian

    Sumarna

    2010-01-01

    Full Text Available This study investigated the possible application of β-glucosidase producing lactic acid bacteria isolated from local fermented foods as a functional starter culture to obtain the bioactive isoflavones, genistein and daidzein, in fermented soymilk. Seven strains of bacteria, Lactobacillus plantarum pentosus SMN 001, Lactobacillus casei subsp rhamnosus FNCC 098, Lactobacillus casei subsp rhamnosus FNCC 099, Lactobacillus casei subsp rhamnosus FNCC 113, Lactobacillus delbrueckii subsp. delbrueckii FNCC 045, Lactobacillus plantarum SMN 025 and Lactobacillus plantarum pentosus FNCC 235 exhibited variable β-glucosidase activity. L. plantarum SMN 025 and L. casei subsp rhamnosus FNCC 098 exhibited the highest β-glucosidase activity of 0.653 and 0.643 U/mL respectively. Acid development, viable populations, β-glucosidase activity and quantification of isoflavone using HPLC were performed at 0, 6, 12, 18, 24 and 30 h of incubation at 41 °C. Seven β-glucosidase-producing strains are able to increase aglycones in fermented soymilk, however, each of the strain produces significantly different bioconversion (p<0.05 of the glucoside isoflavones into their bioactive aglycones. During this fermentation period, with L. plantarum SMN 025, and L. casei subsp rhamnosus FNCC 098, the high level reduced from 150.62 µg/mL (at 24 h to 142.58 µg/mL and from 150.62 µg/mL (at 24 h to 144.71 µg/mL, respectively. The indicate that two β-glucosidase producing lactic acid bacteria have great potential for enrichment of bioactive isoflavones in soymilk fermentation.

  18. Enzymatic hydrolysis of polyester fabrics

    Enzymatic hydrolysis of polyester fabrics has been investigated, using different treatment times, temperature and concentration of enzymes. The effects of hydrolysis on samples were evaluated by measurement of weight loss, moisture regain, breaking load of warp yarns, thickness and Ftir spectroscopy. Results show that hydrolysis under mild conditions can improve moisture absorption of the samples. If the applied temperature, treatment time and concentration exceeded some specific range, the moisture regain would be affected negatively. The Ftir spectrums showed an increase in functional groups specially hydroxyl. However the effects of enzymatic hydrolysis on weight loss, tensile strength and thickness of polyester fabrics were negligible

  19. Photoinitiated coupling of unmodified monosaccharides to iron oxide nanoparticles for sensing proteins and bacteria

    Liu, Li-Hong; Dietsch, Hervé; Schurtenberger, Peter; Yan, Mingdi

    2009-01-01

    We report a versatile approach for the immobilization of unmodified monosaccharides onto iron oxide nanoparticles. Covalent coupling of the carbohydrate onto iron oxide nanoparticle surfaces was accomplished by the CH insertion reaction of photochemically activated phosphate-functionalized perfluorophenylazides (PFPAs), and the resulting glyconanoparticles were characterized by IR, TGA, and TEM. The surface-bound d-mannose showed the recognition ability towards Concanavalin A and Escherichia ...

  20. Decarboxylase Activity of Serratia marcencens Depending on pH and Chosen Monosaccharide Content

    Lazárková, Z.; Andresová, Adéla; Pleva, P.; Lorencová, E.; Buňková, L.; Buňka, F.

    - : WSEAS Press, 2012, s. 224-228. ISBN 978-1-61804-122-7. [International Conference on Agricultural Science, Biotechnology, Food and Animal Science (ABIFA '12). Zlín (CZ), 20.09.2012-22.09.2012] Institutional research plan: CEZ:AV0Z4072921 Keywords : seratia marcescens * pH * monosaccharides Subject RIV: CF - Physical ; Theoretical Chemistry http://www.wseas.us/conferences/2012/zlin/abifa/

  1. Fermentable oligosaccharides, disaccharides, monosaccharides and polyols (FODMAPs) and nonallergic food intolerance: FODMAPs or food chemicals?

    Barrett, Jacqueline S.; Gibson, Peter R

    2012-01-01

    Food intolerance in irritable bowel syndrome (IBS) is increasingly being recognized, with patients convinced that diet plays a role in symptom induction. Evidence is building to implicate fermentable oligosaccharides, disaccharides, monosaccharides and polyols (FODMAPs) in the onset of abdominal pain, bloating, wind and altered bowel habit through their fermentation and osmotic effects. Hypersensitivity to normal levels of luminal distension is known to occur in patients with IBS, with consid...

  2. 酸水解制备纳米纤维素工艺条件的响应面优化%Optimization of Acid Hydrolysis Processing of Nanocellulose Crystal Using Response Surface Methodology

    唐丽荣; 欧文; 林雯怡; 陈燕丹; 陈学榕; 黄彪

    2011-01-01

    Nanocellulose crystal was prepared by sulfuric acid hydrolysis. The effects of sulfuric acid mass fraction, temperature and time on the yield of nanocellulose crystal were optimized with response surface methodology. The mathematical model was established using the Design-Expert software. The effect of various factors and their interactions were analyzed as well. The results showed that quadratic model was the best model to describe the relationship between'the yield of nanocellulose crystal and the factors. The determination coefficient and adjusted determination coefficient were 99. 31 % and 98.43 % , respectively. The interactions between sulfuric acid concentration and temperature, sulfuric acid concentration and time, temperature and time were significant. When suliuric acid concentration, temperature and time corresponded to 54 % , 52 X. And 125 rain, the yield of nanocellulose crystal would reach 69. 31 %. It is the highest value in this investigation.%采用硫酸水解法制备了纳米纤维素,并运用响应面分析法原理,对影响纳米纤维素得率的3个主要影响因素即硫酸质量分数、温度和时间进行优化.利用Design - Expert软件的Box -Benhnken (BBD)模式建立试验数学模型,并对各因素及其相互之间的交互作用进行了分析.结果表明,回归得到的二次多项式模型极显著,模型校正决定系数为98.43%,相关系数为99.31%.硫酸质量分数与温度、硫酸质量分数与时间及温度与时间对纳米纤维素得率的交互作用显著.通过工艺条件优化得出最佳工艺条件为:硫酸质量分数为54%,温度为52℃,时间为125 min,纳米纤维素的得率为69.31%,与理论预测值(69.27%)较好吻合,表明模型是合理有效的.

  3. Combining multivariate analysis and monosaccharide composition modeling to identify plant cell wall variations by Fourier Transform Near Infrared spectroscopy

    Smith-Moritz Andreia M

    2011-08-01

    Full Text Available Abstract We outline a high throughput procedure that improves outlier detection in cell wall screens using FT-NIR spectroscopy of plant leaves. The improvement relies on generating a calibration set from a subset of a mutant population by taking advantage of the Mahalanobis distance outlier scheme to construct a monosaccharide range predictive model using PLS regression. This model was then used to identify specific monosaccharide outliers from the mutant population.

  4. KINETICS OF HYDROLYSIS OF TRIBUTYRIN BY LIPASE

    SULAIMAN AL-ZUHAIR

    2006-06-01

    Full Text Available Kinetics of the enzymatic hydrolysis of tributyrin using lipase has been investigated. The initial rate of reaction was determined experimentally at different substrate concentration by measuring the rate of butyric acid produced. Michaels-Menten kinetic model has been proposed to predict the initial rate of hydrolysis of tributyrin in micro-emulsion system. The kinetic parameters were estimated by fitting the data to the model using three methods, namely, the Lineweaver-Burk, Edie-Hofstee and Hanes methods. The Michaels-Menten model with the constant predicted by Edie-Hofstee and Hanes methods predicted the initial rate of reaction at various substrate concentrations better than the model with the constant predicted Lineweaver-Burk method, especially at high substrate concentrations.

  5. Melittin stimulates phosphoinositide hydrolysis and placental lactogen release: Arachidonic acid as a link between phospholipase A sub 2 and phospholipase C signal-transduction pathways

    Zeitler, P.; Handwerger, S. (Univ. of Cincinnati College of Medicine, OH (USA)); Wu, Y.Q. (Duke Univ. Medical Center, Durham, NC (USA))

    1991-01-01

    Previous investigations from this laboratory have implicated both phospholipase A{sub 2} and phospholipase C in the regulation of human placental lactogen release from human trophoblast. To study further the role of endogenous phospholipase A{sub 2} and the relationship between phospholipase A{sub 2} activation and phosphoinositide metabolism, the authors examined hPL and ({sup 3}H)-inositol release from trophoblast cells in response to agents that stimulate or inhibit the endogenous enzyme. Melittin stimulated rapid, dose-dependent, and reversible increases in the release of hPL, prostaglandin E, and ({sup 3}H)-inositol. Mepacrine inhibited this stimulation. However, mepacrine had no effect on the stimulation of hPL and ({sup 3}H)-inositol release by exogenous arachidonic acid (AA). These results indicate that the stimulation by melittin of phosphoionsitide metabolism and hPL release is mediated by initial activation of phospholipase A{sub 2}. Furthermore, the results support the possibility that AA, released as a consequence of phospholipase A{sub 2} activation, can act as a second messenger linking the two phospholipase pathways.

  6. Process Design and Economics for Biochemical Conversion of Lignocellulosic Biomass to Ethanol: Dilute-Acid Pretreatment and Enzymatic Hydrolysis of Corn Stover

    Humbird, D.; Davis, R.; Tao, L.; Kinchin, C.; Hsu, D.; Aden, A.; Schoen, P.; Lukas, J.; Olthof, B.; Worley, M.; Sexton, D.; Dudgeon, D.

    2011-03-01

    This report describes one potential biochemical ethanol conversion process, conceptually based upon core conversion and process integration research at NREL. The overarching process design converts corn stover to ethanol by dilute-acid pretreatment, enzymatic saccharification, and co-fermentation. Building on design reports published in 2002 and 1999, NREL, together with the subcontractor Harris Group Inc., performed a complete review of the process design and economic model for the biomass-to-ethanol process. This update reflects NREL's current vision of the biochemical ethanol process and includes the latest research in the conversion areas (pretreatment, conditioning, saccharification, and fermentation), optimizations in product recovery, and our latest understanding of the ethanol plant's back end (wastewater and utilities). The conceptual design presented here reports ethanol production economics as determined by 2012 conversion targets and 'nth-plant' project costs and financing. For the biorefinery described here, processing 2,205 dry ton/day at 76% theoretical ethanol yield (79 gal/dry ton), the ethanol selling price is $2.15/gal in 2007$.

  7. Nicosulfuron: alcoholysis, chemical hydrolysis, and degradation on various minerals.

    Sabadie, Jean

    2002-01-30

    Alcoholysis (methanol or ethanol) and hydrolysis (pH ranging from 4 to 11) of the herbicide nicosulfuron at 30 degrees C principally involves the breakdown of the urea part of the molecule. A high yield of the corresponding carbamate was obtained along with aminopyrimidine during alcoholysis. Hydrolysis led to both aminopyrimidine and pyridylsulfonamide. The latter compound may be easily cyclized (pH > or = 7). First-order kinetics describe the rates of alcoholysis and hydrolysis well. The rate constants (0.44 days(-1) for methanolysis) decreased from 0.50 to 0.002 days(-1) as pH increased from 4 to 8, then remained stable under alkaline conditions. In acidic or neutral solution, the hydrolysis path appeared prevalent (> or =70%), whereas in an alkaline medium it decreased when pH increased. The chemical degradation of nicosulfuron on various dry minerals (calcium bentonite, kaolinite, silica gel, H(+) bentonite, montmorillonite K10, and alumina) was investigated at 30 degrees C. The best conditions for the degradation are obtained on acidic minerals after herbicide deposition using the liquid method. Under these conditions an acceptable correlation with pseudo-first-order kinetics was observed, and the major degradation path is similar to that proposed for chemical hydrolysis. Conversely, alumina seemed to favor other unknown degradation processes. The hydrolysis paths of nicosulfuron and rimsulfuron appeared to be different. PMID:11804524

  8. Enzymatic hydrolysis of pretreated barley and wheat straw

    Rosgaard, Lisa

    2007-01-01

    work involved evaluation of 1) possible ways to increase the glucose release from the commercial cellulase product Celluclast by boosting with other enzyme activities to increase the enzymatic hydrolysis, 2) comparing differently pretreated feedstock substrates and 3) evaluating a fed-batch substrate...... feeding strategy to increase the substrate loading in the hydrolysis reaction. The substrate for the enzymatic hydrolysis was primarily steam pretreated wheat and barley straw since these substrates were the primary feedstocks for the Babilafuente Bioethanol process. The initial work showed that there was...... different pretreatment conditions; hot water extraction and acid- or water impregnation followed by steam explosion showed there were slight differences between the effect of pretreatment conditions in relation to the overall yield from enzymatic hydrolysis. The highest glucose concentration was found for...

  9. Determination of free and total myo-inositol in infant formula and adult/pediatric nutritional formula by high- performance anion exchange chromatography with pulsed amperometric detection, including a novel total extraction using microwave-assisted acid hydrolysis and enzymatic treatment: first action 2012.12.

    Ellingson, David; Pritchard, Ted; Foy, Pamela; King, Kathryn; Mitchell, Barbara; Austad, John; Winters, Doug; Sullivan, Darryl; Dowell, Dawn

    2013-01-01

    After an assessment of data generated from a single-laboratory validation study published in J. AOAC Int. 95, 1469-1478 (2012), a method for determining total myo-inositol in infant formula and adult/ pediatric nutritional formula by high-performance anion exchange chromatography with pulsed amperometric detection (HPAEC-PAD), including extraction by using microwave-assisted acid hydrolysis and enzymatic treatment was presented for consideration by AOAC during the AOAC Annual Meeting held in Las Vegas, NV, from September 30 to October 3, 2012. The Expert Review Panel on Infant Formula and Adult Nutritionals concluded that the method met the criteria set by the standard method performance requirements (SMPRs) for the determination of free myo-inositol and approved the method as AOAC Official First Action. The method also determines total myo-inositol, but includes bound sources that the SMPRs exclude. The method involves using HPAEC-PAD for free myo-inositol and a total myo-inositol determination by two different techniques. The first technique uses the conventional acid hydrolysis with 6 h incubation in an autoclave. The second uses a microwave-assisted acid hydrolysis with enzymatic treatment that decreases the extraction time. PMID:24282949

  10. Pretreatment and enzymatic hydrolysis of lignocellulosic biomass

    Corredor, Deisy Y.

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

  11. Hydrolysis of Adiponitrile in Near-critical Water

    DUAN Pei-Gao; NIU Yan-Lei; WANG Yuan-Yuan; DAI Li-Yi

    2008-01-01

    Hydrolysis of adiponitrile (ADN) in near-critical water was successfully conducted in a batch reactor.Influences of m(AND)/m(water) ratio,temperature,time,m(AND)/m(additive) ratio,kind of additive and pressure on the yield of each product were investigated.Five compounds resulting from the hydrolysis of ADN,including 5-cyanovaleramide,adipamide,adipamic acid,adipic acid and trace of 5-cyanovaleric acid,were detected by high performance liquid chromatography.The results showed that change of ADN concentration and temperature had significant influences on the yields of adipamide,adipamic acid and adipic acid;time was the significant factor for the yield of 5-cyanovaleric acid;and the yield of 5-cyanovaleramide was more dependent on the ADN concentration.

  12. Dual Roles of O-Glucose Glycans Redundant with Monosaccharide O-Fucose on Notch in Notch Trafficking.

    Matsumoto, Kenjiroo; Ayukawa, Tomonori; Ishio, Akira; Sasamura, Takeshi; Yamakawa, Tomoko; Matsuno, Kenji

    2016-06-24

    Notch is a transmembrane receptor that mediates cell-cell interactions and controls various cell-fate specifications in metazoans. The extracellular domain of Notch contains multiple epidermal growth factor (EGF)-like repeats. At least five different glycans are found in distinct sites within these EGF-like repeats. The function of these individual glycans in Notch signaling has been investigated, primarily by disrupting their individual glycosyltransferases. However, we are just beginning to understand the potential functional interactions between these glycans. Monosaccharide O-fucose and O-glucose trisaccharide (O-glucose-xylose-xylose) are added to many of the Notch EGF-like repeats. In Drosophila, Shams adds a xylose specifically to the monosaccharide O-glucose. We found that loss of the terminal dixylose of O-glucose-linked saccharides had little effect on Notch signaling. However, our analyses of double mutants of shams and other genes required for glycan modifications revealed that both the monosaccharide O-glucose and the terminal dixylose of O-glucose-linked saccharides function redundantly with the monosaccharide O-fucose in Notch activation and trafficking. The terminal dixylose of O-glucose-linked saccharides and the monosaccharide O-glucose were required in distinct Notch trafficking processes: Notch transport from the apical plasma membrane to adherens junctions, and Notch export from the endoplasmic reticulum, respectively. Therefore, the monosaccharide O-glucose and terminal dixylose of O-glucose-linked saccharides have distinct activities in Notch trafficking, although a loss of these activities is compensated for by the presence of monosaccharide O-fucose. Given that various glycans attached to a protein motif may have redundant functions, our results suggest that these potential redundancies may lead to a serious underestimation of glycan functions. PMID:27129198

  13. Continuous monitoring of enzymatic whey protein hydrolysis. Correlation of base consumption with soluble nitrogen content.

    Margot, A; Flaschel, E.; Renken, A.

    1994-01-01

    The optimization of enzymatic protein hydrolysis often represents a tedious task due to complicated analytical methods. The simplest system of continuous analysis consists of monitoring the base consumption during a pH-controlled reactor operation. However, there are other criteria commonly used for characterizing the extent of protein hydrolysis, comprising the degree of hydrolysis (DH) and the SN-TCA index, that is the fraction of nitrogen soluble in trichloroacetic acid under well-defined ...

  14. Hydrolysis of Fish Protein by Analkaline Protease

    2001-01-01

    Cod muscle protein was hydrolyzed by an alkaline protease in our study. The influences of hydrolysis temperature,fish protein concentration,and ratio of protease addition to protein amount on its degree of hy drolysis (DH) of protein were studied in details by applying dual quadratic rotary combinational design. The final results showed that more than 84% cod muscle protein could be hydrolyzed and recovered. Cod protein hydrolysate thus obtained had a balanced amino acid composition and mainly consisted of small peptides with molecule weight less than 6900 dalton.

  15. The uptake in vitro of dyes, monosaccharides and amino acids by the filarial worm Brugia pahangi

    The uptake of D-glucose and L-leucine by B. pahangi was demonstrated using autoradiographic and scintillation counting techniques and incorporation into worm tissues was detected. Glucose was found to be readily incorporated in the apical, glycogen-rich areas of the myocytes of worms of all ages studied and in the uterine epithelium of the adult female. In contrast, a lower incorporation of D-glucose was found in the eggs, embryos and vas deferens and especially in the gut. The incorporation of L-leucine occurred throughout the tissue of the worms during a 30 min incubation. Labelling was also located over the surface of the cuticle of the worms, when incubated for a period of 15 to 60 min in L-[3H]leucine. Scintillation counting techniques demonstrated that there was no uptake of 14C-labelled L-glucose or sucrose by B. pahangi. The data presented on the uptake in vitro of nutrients or other compounds by infective larvae and adult stages of B. pahangi did not demonstrate an intestinal route of uptake but indicated that the transcuticular route of uptake may be employed. (author)

  16. Optimization of reaction conditions for enzymatic viscosity reduction and hydrolysis of wheat arabinoxylan in an industrial ethanol fermentation residue

    Sørensen, H.R.; Pedersen, S.; Meyer, Anne Boye Strunge

    2006-01-01

    arabinoxylan in the different vinasse fractions irrespective of the state of solubility of the substrate material. The levels of liberated arabinose and xylose increased with increased dry matter concentration during enzymatic hydrolysis in the vinasse and the vinasse supernatant, but at the same time......, increased substrate dry matter concentrations gave corresponding linear decreases in the hydrolytic efficiency as evaluated from levels of monosaccharide release per weight unit dry matter. The study thus documents that enzymatic arabinoxylan hydrolysis of the vinasse significantly decreases the vinasse......This study examined enzyme-catalyzed viscosity reduction and evaluated the effects of substrate dry matter concentration on enzymatic degradation of arabinoxylan in a fermentation residue, "vinasse", resulting from industrial ethanol manufacture on wheat. Enzymatic catalysis was accomplished with a...

  17. 电渗析技术在木糖醇酸水解法制备中的应用%Electrodialysis for production of xylitol from acid hydrolysis method

    汪耀明; 潘升东; 徐铜文

    2015-01-01

    Xylitol is an important sugar alcohol widely used as sweetener. A processing route to remove the residual acid from xylose hydrolyzed solution in industrial production of xylitol is the acid hydrolysis method. Conventional neutralization method with lime has many drawbacks such as high energy consumption, large consumption of chemicals and environmental pollution. To achieve a clean production of xylitol, a self-resemble electrodialysis stack was used for selective removal of residue acid. The influences of current density on the removal ratio of residue acid and recovery ratio of xylose were investigated. The residue acid removal rate was higher than 99% and xylose recovery rate reached 84.9% at a current density of 30 mA·cm?2. The total energy consumption for xylose hydrolyzed solution was 179 kW·h·t?1 and the deacidification process cost was estimated to be 139 ¥·t?1, indicating economic and ecological advantages of this technology. Thus the electrodialysis is a very promising technology for production of xylitol.%木糖醇作为一种可作为甜味剂的糖醇具有广泛的应用前景.目前工业上酸水解法制备木糖醇的过程中需要一个脱除水解液中的残酸的工艺步骤.传统的残酸去除方法为饱和石灰水中和法,存在能耗高、消耗的化学试剂多、污染大等缺点.为实验木糖醇的清洁生产,本文采用自我组装的电渗析装置对木糖水解液中的残酸进行了选择性的去除,考察了操作电流对残酸去除及木糖得率的影响.结果表明,当操作电流为 30 mA·cm?2 时,电渗析过程对残酸的去除率大于 99%,其木糖的得率为 84.9%,电渗析工艺处理木糖水解液的能耗为 179 kW·h·t?1,脱酸工序成本为每吨母液 139 元,具有良好的经济效益和环境效益.由此可见,电渗析工艺在木糖醇酸水解法制备过程中具有广泛的应用前景.

  18. Comparative hydrolysis and fermentation of sugarcane and agave bagasse.

    Hernández-Salas, J M; Villa-Ramírez, M S; Veloz-Rendón, J S; Rivera-Hernández, K N; González-César, R A; Plascencia-Espinosa, M A; Trejo-Estrada, S R

    2009-02-01

    Sugarcane and agave bagasse samples were hydrolyzed with either mineral acids (HCl), commercial glucanases or a combined treatment consisting of alkaline delignification followed by enzymatic hydrolysis. Acid hydrolysis of sugar cane bagasse yielded a higher level of reducing sugars (37.21% for depithed bagasse and 35.37% for pith bagasse), when compared to metzal or metzontete (agave pinecone and leaves, 5.02% and 9.91%, respectively). An optimized enzyme formulation was used to process sugar cane bagasse, which contained Celluclast, Novozyme and Viscozyme L. From alkaline-enzymatic hydrolysis of sugarcane bagasse samples, a reduced level of reducing sugar yield was obtained (11-20%) compared to agave bagasse (12-58%). Selected hydrolyzates were fermented with a non-recombinant strain of Saccharomyces cerevisiae. Maximum alcohol yield by fermentation (32.6%) was obtained from the hydrolyzate of sugarcane depithed bagasse. Hydrolyzed agave waste residues provide an increased glucose decreased xylose product useful for biotechnological conversion. PMID:19000863

  19. Complex enzyme hydrolysis releases antioxidative phenolics from rice bran.

    Liu, Lei; Wen, Wei; Zhang, Ruifen; Wei, Zhencheng; Deng, Yuanyuan; Xiao, Juan; Zhang, Mingwei

    2017-01-01

    In this study, phenolic profiles and antioxidant activity of rice bran were analyzed following successive treatment by gelatinization, liquefaction and complex enzyme hydrolysis. Compared with gelatinization alone, liquefaction slightly increased the total amount of phenolics and antioxidant activity as measured by ferric reducing antioxidant power (FRAP) and oxygen radical absorbance capacity (ORAC) assays. Complex enzyme hydrolysis significantly increased the total phenolics, flavonoids, FRAP and ORAC by 46.24%, 79.13%, 159.14% and 41.98%, respectively, compared to gelatinization alone. Furthermore, ten individual phenolics present in free or soluble conjugate forms were also analyzed following enzymatic processing. Ferulic acid experienced the largest release, followed by protocatechuic acid and then quercetin. Interestingly, a major proportion of phenolics existed as soluble conjugates, rather than free form. Overall, complex enzyme hydrolysis releases phenolics, thus increasing the antioxidant activity of rice bran extract. This study provides useful information for processing rice bran into functional beverage rich in phenolics. PMID:27507440

  20. Site- and species-specific hydrolysis rates of heroin.

    Szöcs, Levente; Orgován, Gábor; Tóth, Gergő; Kraszni, Márta; Gergó, Lajos; Hosztafi, Sándor; Noszál, Béla

    2016-06-30

    The hydroxide-catalyzed non-enzymatic, simultaneous and consecutive hydrolyses of diacetylmorphine (DAM, heroin) are quantified in terms of 10 site- and species-specific rate constants in connection with also 10 site- and species-specific acid-base equilibrium constants, comprising all the 12 coexisting species in solution. This characterization involves the major and minor decomposition pathways via 6-acetylmorphine and 3-acetylmorphine, respectively, and morphine, the final product. Hydrolysis has been found to be 18-120 times faster at site 3 than at site 6, depending on the status of the amino group and the rest of the molecule. Nitrogen protonation accelerates the hydrolysis 5-6 times at site 3 and slightly less at site 6. Hydrolysis rate constants are interpreted in terms of intramolecular inductive effects and the concomitant local electron densities. Hydrolysis fraction, a new physico-chemical parameter is introduced and determined to quantify the contribution of the individual microspecies to the overall hydrolysis. Hydrolysis fractions are depicted as a function of pH. PMID:27130543

  1. Hydrolysis of Nitriles to Carboxylic Acids

    Martínková, Ludmila; Veselá, Alicja Barbara

    Stuttgart: Georg Thieme Verlag KG Stuttgart, 2015 - (Faber, K.; Fessner, W.; Turner, N.), s. 277-302. (Biocatalysis in Organic Synthesis 1). ISBN 978-3-13-174131-8 R&D Projects: GA ČR(CZ) GAP504/11/0394 Institutional support: RVO:61388971 Keywords : nitrilase * nitrile hydratase * amidase Subject RIV: CE - Biochemistry

  2. Muscarinic receptor activation of phosphatidylcholine hydrolysis. Relationship to phosphoinositide hydrolysis and diacylglycerol metabolism

    Martinson, E.A.; Goldstein, D.; Brown, J.H. (Univ. of California, San Diego, La Jolla (USA))

    1989-09-05

    We examined the relationship between phosphatidylcholine (PC) hydrolysis, phosphoinositide hydrolysis, and diacylglycerol (DAG) formation in response to muscarinic acetylcholine receptor (mAChR) stimulation in 1321N1 astrocytoma cells. Carbachol increases the release of (3H)choline and (3H)phosphorylcholine ((3H)Pchol) from cells containing (3H)choline-labeled PC. The production of Pchol is rapid and transient, while choline production continues for at least 30 min. mAChR-stimulated release of Pchol is reduced in cells that have been depleted of intracellular Ca2+ stores by ionomycin pretreatment, whereas choline release is unaffected by this pretreatment. Phorbol 12-myristate 13-acetate (PMA) increases the release of choline, but not Pchol, from 1321N1 cells, and down-regulation of protein kinase C blocks the ability of carbachol to stimulate choline production. Taken together, these results suggest that Ca2+ mobilization is involved in mAChR-mediated hydrolysis of PC by a phospholipase C, whereas protein kinase C activation is required for mAChR-stimulated hydrolysis of PC by a phospholipase D. Both carbachol and PMA rapidly increase the formation of (3H)phosphatidic acid ((3H)PA) in cells containing (3H)myristate-labeled PC. (3H)Diacylglycerol ((3H)DAG) levels increase more slowly, suggesting that the predominant pathway for PC hydrolysis is via phospholipase D. When cells are labeled with (3H)myristate and (14C)arachidonate such that there is a much greater 3H/14C ratio in PC compared with the phosphoinositides, the 3H/14C ratio in DAG and PA increases with PMA treatment but decreases in response to carbachol.

  3. Explicit Consideration of Water Molecules to Study Vibrational Circular DICHROÎSM of Monosaccharide's

    Moussi, Sofiane; Ouamerali, Ourida

    2014-06-01

    Carbohydrates have multiples roles in biological systems. It has been found that the glycoside bond is fundamentally important in many aspects of chemistry and biology and forms the basis of carbohydrate chemistry. That means the stereochemical information, namely, glycosidic linkages α or β, gives an significant features of the carbohydrate glycosidation position of the glycosylic acceptor. For these reasons, much effort was made for the synthesis and analysis of the glycoside bond. Vibrational circular dichroism VCD has some advantages over conventional electronic circular dichroism (ECD) due to the applicability to all organic molecules and the reliability of ab initio quantum calculation. However, for a molecule with many chiral centers such as carbohydrates, determination of the absolute configuration tends to be difficult because the information from each stereochemical center is mixed and averaged over the spectrum. In the CH stretching region, only two VCD studies on carbohydrates have been reported and spectra--structure correlation, as determined for the glycoside band, remains to be investigated. T. Taniguchi and collaborators report that methyl glycosides exhibit a characteristic VCD peak, the sign of which solely reflects the C-1 absolute configuration. This work is a theoretical contribution to study the behaviour of VCD spectrum's of the monosaccharides when the water molecules are taken explicitly. This study is focused on six different monosaccharides in theirs absolute configuration R and S. We used the method of density functional theory DFT by means of the B3LYP hybrid functional and 6-31G * basis set.

  4. Effects of culture conditions on monosaccharide composition of Ganoderma lucidum exopolysaccharide and on activities of related enzymes.

    Peng, Lin; Qiao, Shuangkui; Xu, Zhenghong; Guan, Feng; Ding, Zhongyang; Gu, Zhenghua; Zhang, Liang; Shi, Guiyang

    2015-11-20

    We investigated the relationship between monosaccharide composition of Ganoderma lucidum exopolysaccharide (EPS) and activities of EPS synthesis enzymes under various culture temperatures and initial pH values. The mole percentages of three major EPS monosaccharides, glucose, galactose and mannose, varied depending on culture conditions and the resulting EPS displayed differing anti-tumor activities. In nine tested enzymes, higher enzyme activities were correlated with higher temperature and lower initial pH. Altered mole percentages of galactose and mannose under various culture conditions were associated with activities of α-phosphoglucomutase (PGM) and phosphoglucose isomerase (PGI), respectively, and that of mannose was also associated with phosphomannose isomerase (PMI) activity only under various pH. Our findings suggest that mole percentages of G. lucidum EPS monosaccharides can be manipulated by changes of culture conditions that affect enzyme activities, and that novel fermentation strategies based on this approach may enhance production and biological activity of EPS. PMID:26344261

  5. Penicillin Hydrolysis: A Kinetic Study of a Multistep, Multiproduct Reaction.

    McCarrick, Thomas A.; McLafferty, Fred W.

    1984-01-01

    Background, procedures used, and typical results are provided for an experiment in which students carry out the necessary measurements on the acid-catalysis of penicillin in two hours. By applying kinetic theory to the data obtained, the reaction pathways for the hydrolysis of potassium benzyl penicillin are elucidated. (JN)

  6. Chemical and enzymatic hydrolysis of anthraquinone glycosides from Madder roots

    Derksen, G.C.H.; Naayer, M.; Beek, T.A. van; Capelle, A.; Haaksman, I.K.; Doren, H.A. van; Groot, Æ. de

    2003-01-01

    For the production of a commercially useful dye extract from madder, the glycoside ruberythric acid has to be hydrolysed to the aglycone alizarin which is the main dye component. An intrinsic problem is the simultaneous hydrolysis of the glycoside lucidin pritneveroside to the unwanted mutagenic agl

  7. Chemical and enzymatic hydrolysis fo anthraquinone glycosides from madder roots

    Derksen, G.C.H.; Naayer, M.; Beek, van T.A.; Capelle, A.; Haaksman, I.K.; Doren, H.A.; Groot, de Æ.

    2003-01-01

    For the production of a commercially useful dye extract from madder, the glycoside ruberythric acid has to be hydrolysed to the aglycone alizarin which is the main dye component. An intrinsic problem is the simultaneous hydrolysis of the glycoside lucidin primeveroside to the unwanted mutagenic agly

  8. DFT STUDY OF THE HYDROLYSIS OF SOME S-TRIAZINES

    The acid-catalyzed hydrolysis of atrazine and related 2-chloro-s-triazines to the corresponding 2-hydroxy-s-triazines was investigated using the B3LYP hybrid density functional theory method. Gas-phase calculations were performed at the B3LYP/6-311++G(d,p)//B3LYP/6-31G* level of ...

  9. The Preparation and Enzymatic Hydrolysis of a Library of Esters

    Sanford, Elizabeth M.; Smith, Traci L.

    2008-01-01

    An investigative case study involving the preparation of a library of esters using Fischer esterification and alcoholysis of acid chlorides and their subsequent enzymatic hydrolysis by pig liver esterase and orange peel esterase is described. Students work collaboratively to prepare and characterize the library of esters and complete and evaluate…

  10. Fuzzy logic feedback control for fed-batch enzymatic hydrolysis of lignocellulosic biomass.

    Tai, Chao; Voltan, Diego S; Keshwani, Deepak R; Meyer, George E; Kuhar, Pankaj S

    2016-06-01

    A fuzzy logic feedback control system was developed for process monitoring and feeding control in fed-batch enzymatic hydrolysis of a lignocellulosic biomass, dilute acid-pretreated corn stover. Digested glucose from hydrolysis reaction was assigned as input while doser feeding time and speed of pretreated biomass were responses from fuzzy logic control system. Membership functions for these three variables and rule-base were created based on batch hydrolysis data. The system response was first tested in LabVIEW environment then the performance was evaluated through real-time hydrolysis reaction. The feeding operations were determined timely by fuzzy logic control system and efficient responses were shown to plateau phases during hydrolysis. Feeding of proper amount of cellulose and maintaining solids content was well balanced. Fuzzy logic proved to be a robust and effective online feeding control tool for fed-batch enzymatic hydrolysis. PMID:26915095

  11. Moringa oleifera aqueous leaf extract inhibits reducing monosaccharide-induced protein glycation and oxidation of bovine serum albumin.

    Nunthanawanich, Pornpimon; Sompong, Weerachat; Sirikwanpong, Sukrit; Mäkynen, Kittana; Adisakwattana, Sirichai; Dahlan, Winai; Ngamukote, Sathaporn

    2016-01-01

    Advanced glycation end products (AGEs) play an important factor for pathophysiology of diabetes and its complications. Moringa oleifera is one of the medicinal plants that have anti-hyperglycemic activity. However, anti-glycation property of Moringa oleifera leaf extract on the different types of reducing monosaccharides-induced protein glycation has not been investigated. Therefore, the aim of this study was to examine the protective effect of Moringa oleifera aqueous leaf extract (MOE) on reducing sugars-induced protein glycation and protein oxidation. Total phenolic content of MOE was measured using the Folin-Ciocalteu method. Bovine serum albumin was incubated with 0.5 M of reducing sugars (glucose or fructose) with or without MOE (0.5-2.0 mg/mL) for 1, 2, 3 and 4 weeks. The results found that total phenolic content was 38.56 ± 1.50 mg gallic acid equivalents/g dry extract. The formation of fluorescent and non-fluorescent AGEs [N (ε)-(carboxymethyl) lysine (CML)] and the level of fructosamine were determined to indicate protein glycation, whereas the level of protein carbonyl content and thiol group were examined for protein oxidation. MOE (0.5-2.0 mg/mL) significantly inhibited the formation of fluorescent, N (ε)-CML and markedly decreased fructosamine level (P < 0.05). Moreover, MOE significantly prevented protein oxidation manifested by reducing protein carbonyl and the depletion of protein thiol in a dose-dependent manner (P < 0.05). Thus, the findings indicated that polyphenols containing in MOE have high potential for decreasing protein glycation and protein oxidation that may delay or prevent AGE-related diabetic complications. PMID:27468399

  12. Effect of acid hydrolysis combined with moist heat treatment on the properties of pea starch%酸水解-湿热处理对豌豆淀粉特性的影响

    韩忠杰; 熊柳; 孙庆杰; 孙盈乾

    2012-01-01

    以豌豆淀粉为原料,利用不同pH值和水分含量的酸水解结合湿热处理对其进行复合改性。结果表明,复合改性后豌豆淀粉直链淀粉含量升高,溶胀度和溶解度降低。经酸解结合湿热处理改性后淀粉的峰值黏度(PKV),谷值黏度(TV)、终值黏度(FNV),衰减值(BD)和回生值(SB)都降低但是糊化温度(PT)升高。糊化温度在水分含量为30%,pH4时达到最高值86.75℃,比原淀粉高13.45℃。复合改性豌豆淀粉的凝胶硬度,黏度,内聚力都比原淀粉低。水分含量为30%,pH3改性后的豌豆淀粉凝胶硬度降低了426.33g。豌豆淀粉改性后的特性可使其制作的粉丝耐蒸煮,不易糊汤,质构柔滑。%Pea starch was modified combined with moist heat treatment increased, but the swelling degree by different pH and acid hydrolysis with different moisture content The results showed that the amylose content of modified pea starch and solubility decreased. The peak viscosity, trough viscosity, final viscosity, attenuation and setback of modified starch were decreased but the gelatinization temperature was increased. The gelatinization temperature reached to 86.75 ℃ while starch treated by moisture con- tent 30% , pH 4, which was about 13.45 ℃ higher than that of the original starch. The hardness, vis- cosity and cohesiveness of the gel of the modified starch were lower than the original starch. Gel hardness of pea starch treated by moisture content of 30% and pH 3 decreased 426.33 g compared with the origi- nal starch. These features can contribute to vermicelli made of modified pea starch resistance cooking, not easy to paste soup and texture smooth.

  13. Effects of acid hydrolysis and annealing treatment on the properties of corn starch%酸解结合热处理对玉米淀粉性质影响

    姬娜; 熊柳; 孙庆杰

    2013-01-01

    利用酸水解结合热处理对玉米淀粉进行复合改性。研究不同pH、温度对玉米淀粉性质影响。实验结果表明,酸解结合热处理会使部分改性淀粉溶胀度降低、可溶指数升高,糊化温度升高。大多酸解结合热处理玉米淀粉样品峰值粘度、谷值粘度、最终粘度、衰减值和回生值低于其原淀粉。当pH=1时,酸解结合热处理玉米淀粉没有糊化曲线。改性玉米淀粉最大凝胶硬度为76.55 g,高于原淀粉,但是其凝胶弹性和内聚性变化不大。酸解结合热处理玉米淀粉Tc-To下降了,ΔH从11.41 J/g降到9.65 J/g。改性后玉米淀粉结晶峰型仍为A型,且相对结晶度降低。%In this article,corn starch(CS)samples modified by acid hydrolysis(AH)combined with annealing treatment(ANN)were made by changing pH and treated temperature. Swelling power of most modified starches decreased,while solubility increased. Peak viscosity(PKV),trough viscosity(TV), final viscosity(FNV),breakdown(BD)and setback(SB)of most modified starches were lower than that of native starch. When pH was 1,starches modified by AH-ANN had no gelatinization curves. The biggest hardness of modified starch gel was 76.55 g,improving 21.61 g compared with native starch gel. While gel springiness and cohesiveness of all treated starch samples had no significantly change. Compared to the native starch,Tc-To decreased andΔH decreased from 11.41 J/g to 9.65 J/g. Modified CS exhibited“A”type X-ray pattern. Relative crystallinity decreased after AH-ANN.

  14. Experimental studies on the ring opening polymerization of p-dioxanone using an Al((OPr)-Pr-i)(3)-monosaccharide initiator system

    Sugih, Asaf Kleopas; Picchioni, Francesco; Heeres, Hero J.

    2009-01-01

    The ring opening polymerization (ROP) of p-dioxanone using a protected monosaccharide (1,2;3.4-di-O-isopropylidene-alpha-D-galactopyranose)/Al((OPr)-Pr-i)(3) initiator system to yield polydioxanone with a protected monosaccharide end-group is described. The products were synthesized at 60-100 degree

  15. Molecular cloning, functional characterization and expression analysis of a novel monosaccharide transporter gene OsMST6 from rice (Oryza sativa L.)

    Wang, Y.; Xiao, Y.; Zhang, Y.; Chai, C.; Wei, G.; Wei, X.; Xu, H.; Wang, M.; Ouwerkerk, P.B.F.; Zhu, Z.

    2008-01-01

    Monosaccharides transporters play important roles in assimilate supply for sink tissue development. In this study, a new monosaccharide transporter gene OsMST6 was identified from rice (Oryza sativa L.). The predicted OsMST6 protein shows typical features of sugar transporters and shares 79.6% ident

  16. STUDY OF ENZYMATIC HYDROLYSIS OF MILD PRETREATED LIGNOCELLULOSIC BIOMASSES

    Michael Ioelovich; Ely Morag

    2012-01-01

    The effect of mild acidic and alkaline pretreatments of various plant biomasses on their enzymatic hydrolysis has been studied. The yield of reducing sugars and utilization rate of the biomass were used as reliable characteristics of enzymatic digestibility of the biomasses. The experiments showed that alkaline pretreatment was more efficient than acidic pretreatment. As a result of alkaline pretreatment, a more efficient delignification of the biomasses and considerable improvement of the di...

  17. The dynamics of acid-soluble phosphorus compounds in the course of winter and spring wheat germination under various thermic conditions. Part II. Labile phosphorus after hydrolysis of the acid-soluble fraction

    A. Barbaro

    2015-06-01

    Full Text Available The changes in labile phosphorus compounds content during germination of wheat were investigated. These compounds were determined in acid-soluble germ extracts separated into fractions according to the solubility of their barium salts. Low germination temperature was found to raise the labile phosphorus content in the fraction of insoluble barium salts. If we assume that labile P of this fraction consisted mainly of adenosinedi- and triphosphates, it would seem that the rise, in the ATP and ADP level under the influence of low temperature may be essential for initiating flowering in winter varieties.

  18. Hydrolysis of green tea residue protein using proteolytic enzyme derived from Aspergillus oryzae.

    Xu, Yong-Quan; Zhong, Xiao-Yu; Chen, Su-Qin; Yin, Jun-Feng

    2013-02-01

    Free amino acids are important chemical components which impact the taste of green tea infusion. The hydrolysis of water-insoluble protein in the green tea residue helps to increase the contents of free amino acids components except theanine. Studies indicate that the hydrolysis of the tea protein could be restricted due to interaction of polyphenols with protein. The experiment indicates that the hydrolysis of tea protein by protease is the main trend when the polyphenols concentration is lower than 5 mg ml(-1), however, the proteins (including tea protein and protease) would interact with polyphenoles instead of hydrolysis when the concentration of polyphenols is higher than 5 mg ml(-1). The hydrolysis of tea protein is absolutely restrained when concentration comes to 10 mg ml(-1). PMID:24425904

  19. Distinguishing Monosaccharide Stereo- and Structural Isomers with ToF-SIMS and Multivariate Statistical Analysis

    Berman, E F; Kulp, K S; Knize, M G; Wu, L; Nelson, E J; Nelson, D O; Wu, K J

    2006-05-04

    Time-of-Flight Secondary Ion Mass Spectrometry (ToF-SIMS) is utilized to examine the mass spectra and fragmentation patterns of seven isomeric monosaccharides. Multivariate statistical analysis techniques, including principal component analysis (PCA), allow discrimination of the extremely similar mass spectra of stereoisomers. Furthermore, PCA identifies those fragment peaks which vary significantly between spectra. Heavy isotope studies confirm that these peaks are indeed sugar fragments, allow identification of the fragments, and provide clues to the fragmentation pathways. Excellent reproducibility is shown by multiple experiments performed over time and on separate samples. This study demonstrates the combined selectivity and discrimination power of ToF-SIMS and PCA, and suggests new applications of the technique including differentiation of subtle chemical changes in biological samples that may provide insights into cellular processes, disease progress, and disease diagnosis.

  20. Fermentable oligosaccharides, disaccharides, monosaccharides and polyols (FODMAPs) and nonallergic food intolerance: FODMAPs or food chemicals?

    Barrett, Jacqueline S; Gibson, Peter R

    2012-07-01

    Food intolerance in irritable bowel syndrome (IBS) is increasingly being recognized, with patients convinced that diet plays a role in symptom induction. Evidence is building to implicate fermentable oligosaccharides, disaccharides, monosaccharides and polyols (FODMAPs) in the onset of abdominal pain, bloating, wind and altered bowel habit through their fermentation and osmotic effects. Hypersensitivity to normal levels of luminal distension is known to occur in patients with IBS, with consideration of food chemical intolerance likely to answer many questions about this physiological process. This paper summarizes the evidence and application of the most common approaches to managing food intolerance in IBS: the low-FODMAP diet, the elimination diet for food chemical sensitivity and others including possible noncoeliac gluten intolerance. PMID:22778791

  1. Enzymatic hydrolysis of fructans in the tequila production process.

    Avila-Fernández, Angela; Rendón-Poujol, Xóchitl; Olvera, Clarita; González, Fernando; Capella, Santiago; Peña-Alvarez, Araceli; López-Munguía, Agustín

    2009-06-24

    In contrast to the hydrolysis of reserve carbohydrates in most plant-derived alcoholic beverage processes carried out with enzymes, agave fructans in tequila production have traditionally been transformed to fermentable sugars through acid thermal hydrolysis. Experiments at the bench scale demonstrated that the extraction and hydrolysis of agave fructans can be carried out continuously using commercial inulinases in a countercurrent extraction process with shredded agave fibers. Difficulties in the temperature control of large extraction diffusers did not allow the scaling up of this procedure. Nevertheless, batch enzymatic hydrolysis of agave extracts obtained in diffusers operating at 60 and 90 degrees C was studied at the laboratory and industrial levels. The effects of the enzymatic process on some tequila congeners were studied, demonstrating that although a short thermal treatment is essential for the development of tequila's organoleptic characteristics, the fructan hydrolysis can be performed with enzymes without major modifications in the flavor or aroma, as determined by a plant sensory panel and corroborated by the analysis of tequila congeners. PMID:19473003

  2. Production of Fish Hydrolysates Protein from Waste of Fish Carp (Cyprinus Carpio) By Enzymatic Hydrolysis

    Dede Saputra; Tati Nurhayati

    2016-01-01

    Fish Protein Hydrolysates (FPH) is the mixed products of polypeptide, dipeptides, and amino acid. It can be produced from materials that contained of protein by acid reaction, base reaction or enzymatic hydrolysis. The objectives of this study were to study the production of FPH from fish carp meat at post rigor phase and viscera by enzymatic hydrolysis, to determine the specific activity of papain enzyme, and to determine the solubility of FPH. Capacity of fish hydrolyzing can be...

  3. Spectrophotometric determination of paracetamol in pharmaceuticals using microwave-assisted hydrolysis and a micellar medium

    Sequinel, Rodrigo; José L. Rufino; Pezza, Helena; Pezza, Leonardo

    2011-01-01

    A new spectrophotometric method employing a micellar medium is proposed for the determination of paracetamol in pharmaceuticals. The method is based on the acid hydrolysis of paracetamol to p-aminophenol (PAP), which under acidic conditions reacts with p-dimethylaminocinnamaldehyde (pDAC), producing a red compound (λmax = 530 nm). This reaction can be enhanced five-fold in the presence of sodium dodecyl sulfate (SDS). The effects of all the parameters involved in both the hydrolysis step...

  4. Cellulase hydrolysis of unsorted MSW

    Jensen, Jacob Wagner; Felby, Claus; Jørgensen, Henning

    A recent development in waste management and engineering has shown that the cellulase can be used for the liquefaction of organic fractions in household waste. The focus of this study was to optimize the enzyme hydrolysis of thermally treated municipal solid waste (MSW) by the addition of...

  5. Switching Catalysis from Hydrolysis to Perhydrolysis in Pseudomonas fluorescens Esterase

    Yin, D.; Bernhardt, P; Morley, K; Jiang, Y; Cheeseman, J; Purpero, V; Schrag, J; Kazlauskas, R

    2010-01-01

    Many serine hydrolases catalyze perhydrolysis, the reversible formation of peracids from carboxylic acids and hydrogen peroxide. Recently, we showed that a single amino acid substitution in the alcohol binding pocket, L29P, in Pseudomonas fluorescens (SIK WI) aryl esterase (PFE) increased the specificity constant of PFE for peracetic acid formation >100-fold [Bernhardt et al. (2005) Angew. Chem., Int. Ed. 44, 2742]. In this paper, we extend this work to address the three following questions. First, what is the molecular basis of the increase in perhydrolysis activity? We previously proposed that the L29P substitution creates a hydrogen bond between the enzyme and hydrogen peroxide in the transition state. Here we report two X-ray structures of L29P PFE that support this proposal. Both structures show a main chain carbonyl oxygen closer to the active site serine as expected. One structure further shows acetate in the active site in an orientation consistent with reaction by an acyl-enzyme mechanism. We also detected an acyl-enzyme intermediate in the hydrolysis of {var_epsilon}-caprolactone by mass spectrometry. Second, can we further increase perhydrolysis activity? We discovered that the reverse reaction, hydrolysis of peracetic acid to acetic acid and hydrogen peroxide, occurs at nearly the diffusion limited rate. Since the reverse reaction cannot increase further, neither can the forward reaction. Consistent with this prediction, two variants with additional amino acid substitutions showed 2-fold higher k{sub cat}, but K{sub m} also increased so the specificity constant, k{sub cat}/K{sub m}, remained similar. Third, how does the L29P substitution change the esterase activity? Ester hydrolysis decreased for most esters (75-fold for ethyl acetate) but not for methyl esters. In contrast, L29P PFE catalyzed hydrolysis of {var_epsilon}-caprolactone five times more efficiently than wild-type PFE. Molecular modeling suggests that moving the carbonyl group closer to the

  6. Enzymatic hydrolysis of potato pulp

    Mariusz Lesiecki

    2012-03-01

    Full Text Available Background. Potato pulp constitutes a complicated system of four types of polysaccharides: cellulose, hemicellulose, pectin and starch. Its composition makes it a potential and attractive raw material for the production of the second generation bioethanol. The aim of this research project was to assess the usefulness of commercial enzymatic preparations for the hydrolysis of potato pulp and to evaluate the effectiveness of hydrolysates obtained in this way as raw materials for ethanol fermentation. Material  and methods. Sterilised potato pulp was subjected to hydrolysis with commercial enzymatic preparations. The effectiveness of the preparations declared as active towards only one fraction of potato pulp (separate amylase, pectinase and cellulase activity and mixtures of these preparations was analysed. The monomers content in hydrolysates was determined using HPLC method. Results.  The application of amylolytic enzymes for potato pulp hydrolysis resulted in the release of only 18% of raw material with glucose as the dominant (77% constituent of the formed product. In addition, 16% galactose was also determined in it. The hydrolysis of the cellulose fraction yielded up to 35% raw material and the main constituents of the obtained hydrolysate were glucose (46% and arabinose (40%. Simultaneous application of amylolytic, cellulolytic and pectinolytic enzymes turned out to be the most effective way of carrying out the process as its efficiency in this case reached 90%. The obtained hydrolysate contained 63% glucose, 25% arabinose and 12% other simple substances. Conclusion. The application of commercial enzymatic preparations made it possible to perform potato pulp hydrolysis with 90% effectiveness. This was achieved by the application of a complex of amylolytic, cellulolytic and pectinolytic enzymes and the hydrolysate obtained in this way contained, primarily, glucose making it a viable substrate for ethanol fermentation.

  7. Partial Hydrolysis of the Fucosylated Chondroitin Sulfate from Sea Cucumber Isostichopus badionotus and Its Mechanism

    CHEN Shi-Guo; LI Guo-Yun; YE Xing-Qian; XUE Chang-Hu

    2012-01-01

    The method for preparing low molecular weight fucosylated chondroitin sulfate from sea cucumber lsostichopus badionotus using partial acid hydrolysis was reported, and its hydrolysis mechanism was also investigated. The sea cucumber chondroitin sulfate FCS was hydrolyzed under different conditions (80℃3 h and 6 h), then isolated and purified on a Bio-P-4 geltration to prepare low molecular weight fractions (LMWF-FCS). The chemical compositions of LMWF-FCS showed the branched fucose (Fuc) was cleaved during acid hydrolysis process, whereas the mole ratio of acetyl-galactosamine (GalNAc) and glucuronic acid (GlcA) in the backbone remained the same, which indicated the backbone was a typical chondroitin sulfate structure. The disaccharide composition analysis of LMWF-FCS suggested that the sulfation patterns of GalNAc in the backbone chain changed and the substitution value was reduced. Furthermore, the 1D NMR analysis illustrated the branched-Fuc was cleaved during acid hydrolysis, but their substitution patterns were not influenced, which was distinct from the previous reports that the substitutions of branched-Fuc in FCS were easy to change. Simultaneously, the sulfation pattern of GalNAc in backbone chain changed obviously in the acid hydrolysis process. The anticoagulant activity in vitro illuminated the anticoagulant activity of the degradation products over time in the acid hydrolysis are gradually declined, but still kept good. Therefore, the LMWF-FCS prepared could be developed as a new anticoagulant and antithrombotic drug like low molecular weight heparin.

  8. Effect of acid hydrolysis combined with moist heat treatment on physicochemical properties of potato starch%酸热处理对马铃薯淀粉理化性质的影响

    邱超; 姬娜; 朱晓蕾; 熊柳; 孙庆杰

    2015-01-01

    The effect of pH value,moisture content and temperature on modification of potato starch (PS) was studied.The result showed that after being treated by partial acid hydrolysis (AH)combined with heat moisture treatment (HMT),the amylose content in PS increased,while soluble amylose content de-creased;Solubility and swelling power of most modified starches decreased;Peak viscosity (PKV ), trough viscosity (TV),final viscosity (FNV),attenuation and setback decreased;But gel hardness of some modified starches was higher than native starch.The biggest hardness of starch gel was 143.42 g, which was about 4.2 times higher than native PS,while gel springiness and cohesiveness of all modified starches decreased.To,Tc,Tp and Tc-To of PS modified starches significantly increased,butΔH de-creased.Crystallized potato starch was B-type,the peak of modified PS at 5.9°(2θ)decreased,double peak at 22~25 °(2θ)decreased too,and even became into a single wide peaks.%以马铃薯淀粉为原料,研究不同pH值、水分含量和处理温度对马铃薯淀粉复合改性效果。结果表明,马铃薯淀粉经部分酸解结合湿热处理复合改性后,直链淀粉含量增加,但可溶性直连淀粉含量降低。复合改性后马铃薯淀粉溶胀度和溶解度降低。经部分酸解结合湿热处理改性后马铃薯淀粉的峰值黏度(PKV)、谷值黏度(TV)、终值黏度(FNV)、衰减值(BD)和回生值(SB)都降低。但是复合改性后马铃薯淀粉的凝胶硬度增加,最大的硬度达到了143.42 g,是原淀粉的4.2倍,而黏度、内聚力都降低。复合改性后马铃薯淀粉的To、Tp、Tc 和Tc -To都显著升高,但ΔH显著降低。X-衍射测定结果表明马铃薯淀粉结晶为B型,复合改性后马铃薯淀粉在5.9°(2θ)产生的B型特征峰减小,在22~25°(2θ)出现的双峰减小,甚至有变为单峰的趋势。

  9. Direct conversion of corn cob to formic and acetic acids over nano oxide catalysts

    Liyuan; Cheng; Hong; Liu; Yuming; Cui; Nianhua; Xue; Weiping; Ding

    2014-01-01

    Considering energy shortage, large molecules in corn cob and easy separation of solid catalysts, nano oxides are used to transform corn cob into useful chemicals. Because of the microcrystals, nano oxides offer enough accessible sites for cellulose, hemicellulose and monosaccharide from corn cob hydrolysis and oxidant. Chemical conversion of corn cob to organic acids is investigated over nano ceria, alumina, titania and zirconia under various atmospheres. Liquid products are mainly formic and acetic acids. A small amount of other compounds, such as D-xylose,D-glucose, arabinose and xylitol are also detected simultaneously. The yield of organic acids reaches 25%–29% over the nano oxide of ceria,zirconia and alumina with 3 h reaction time under 453 K and 1.2 MPa O2. The unique and fast conversion of corn cob is directly approached over the nano oxides. The results are comparative to those of biofermentation and offer an alternative method in chemically catalytic conversion of corn cob to useful chemicals in a one-pot chemical process.

  10. Catalytic hydrolysis for the degradation of organophosphorus pesticides in water

    The kinetic studies of catalytic hydrolysis revealed that the concentration of two kinds of organophosphorus pesticides (omethoate and methidathion) in solution apparently decays according to the second order reaction. It was found that the rate constant value was highest at strong acidic conditions and it continued to decrease as the pH of the solution was increased. At basic conditions the rate constant value decreased to minimum. Manganese dioxide under acidic conditions converted into Mn/sup 2+/ ions and then these ions in water form hexaaquomanganese (II) ion. This hexaaquomanganese (II ion then adsorbed itself on the S or O atom of the organophosphorus compound and thus weakens the bond between P-S. This reaction facilitated the attack of H/sub 2/O or OH/sup -/ ion and thus enhanced the efficiency of hydrolysis. It was studied that methidathion hydrolyzed more efficiently than omethoate The rate constants of catalytic hydrolysis were increased with increasing the amount of MnO/sub 2/. It was found that the pesticides had undergone adsorption on catalyst in the first few minutes and there was the rapid drop of total phosphorus concentration. The decrease of total phosphorus adsorption with increasing pH was also observed. After the addition of alkaline earth metal cations (Ca/sup 2+/ and Mg/sup 2+/) along with magnesium, the enhancement in the efficiency of hydrolysis at near neutral conditions occurred. (author)

  11. Small peptides hydrolysis in dry-cured meats.

    Mora, Leticia; Gallego, Marta; Escudero, Elizabeth; Reig, Milagro; Aristoy, M-Concepción; Toldrá, Fidel

    2015-11-01

    Large amounts of different peptides are naturally generated in dry-cured meats as a consequence of the intense proteolysis mechanisms which take place during their processing. In fact, meat proteins are extensively hydrolysed by muscle endo-peptidases (mainly calpains and cathepsins) followed by exo-peptidases (mainly, tri- and di-peptidyl peptidases, dipeptidases, aminopeptidases and carboxypeptidases). The result is a large amount of released free amino acids and a pool of numerous peptides with different sequences and lengths, some of them with interesting sequences for bioactivity. This manuscript is presenting the proteomic identification of small peptides resulting from the hydrolysis of four target proteins (glyceraldehyde-3-phosphate dehydrogenase, beta-enolase, myozenin-1 and troponin T) and discusses the enzymatic routes for their generation during the dry-curing process. The results indicate that the hydrolysis of peptides follows similar exo-peptidase mechanisms. In the case of dry-fermented sausages, most of the observed hydrolysis is the result of the combined action of muscle and microbial exo-peptidases except for the hydrolysis of di- and tri-peptides, mostly due to microbial di- and tri-peptidases, and the release of amino acids at the C-terminal that appears to be mostly due to muscle carboxypeptidases. PMID:25944374

  12. Mechanisms of lactone hydrolysis in neutral and alkaline conditions.

    Gómez-Bombarelli, Rafael; Calle, Emilio; Casado, Julio

    2013-07-19

    The neutral and base-catalyzed hydrolysis of nine carboxylic acid esters was studied using a hybrid supermolecule-PCM approach including six explicit water molecules. The molecules studied included two linear esters, four β-lactones, two γ-lactones, and one δ-lactone: ethyl acetate and methyl formate, β-propiolactone, β-butyrolactone, β-isovalerolactone, diketene (4-methyleneoxetan-2-one), γ-butyrolactone, 2(5H)-furanone, and δ-valerolactone. DFT and ab initio methods were used to analyze the features of the various possible hydrolysis mechanisms. For all compounds, reasonable to very good qualitative and quantitative agreement with experimental work was found, and evidence is provided to support long-standing hypotheses regarding the role of solvent molecule as a base catalyst. In addition, novel evidence is presented for the existence of an elimination-addition mechanism in the basic hydrolysis of diketene. A parallel work addresses the acid-catalyzed hydrolysis of lactones. PMID:23758295

  13. The effect of natural antioxidants on haemoglobin-mediated lipid oxidation during enzymatic hydrolysis of cod protein.

    Halldorsdottir, Sigrun M; Kristinsson, Hordur G; Sveinsdottir, Holmfridur; Thorkelsson, Gudjon; Hamaguchi, Patricia Y

    2013-11-15

    Heating and changes in pH often practised during fish protein hydrolysis can cause lipid oxidation. The effect of natural antioxidants towards haemoglobin-mediated lipid oxidation during enzymatic hydrolysis of cod proteins was investigated. Different variants of a washed cod model system, containing different combinations of haemoglobin and natural antioxidants (l-ascorbic acid and Fuscus vesiculosus extract), were hydrolysed using Protease P "Amano" 6 at pH 8 and 36°C to achieve 20% degree of hydrolysis. Lipid hydroperoxides and thiobarbituric acid reactive substances (TBARS) were analysed periodically during the hydrolysis process. The in vitro antioxidant activity of the final products was investigated. Results indicate that oxidation can develop rapidly during hydrolysis and antioxidant strategies are preferable to produce good quality products. Oxidation products did not have an impact on the in vitro antioxidant activity of the hydrolysates. The natural antioxidants inhibited oxidation during hydrolysis and contributed to the antioxidant activity of the final product. PMID:23790867

  14. Effect of nitrogen oxide pretreatments on enzymatic hydrolysis of cellulose

    Borrevik, R.K.; Wilke, C.R.; Brink, D.L.

    1978-09-01

    This work considers the effect of nitrogen oxide pretreatments on the subsequent enzymatic hydrolysis by Trichoderma viride cellulase of the cellulose occurring in wheat straw; Triticum Aestivum-L, em. Thell. In the pretreatment scheme the straw is first reacted with nitric oxide and air, and then extracted in aqueous solution. In this way, overall sugar yields increased from 17% for the case of no pretreatment to 70%. The glucose yield increased from 20 to 60%. The yield of glucose during enzymatic hydrolysis is dependent on the reaction time of the gas phase reaction. For a 24 hour reaction the yield is 60%, but drops to 45% for a reaction time of 2 hours. Xylose, a potentially valuable side product of the pretreatment, is obtained by dilute acid hydrolysis during the extraction stage in yields of 90 to 96%. In acidic media, the kinetics of both the rate of formation and destruction of xylose were found to follow the first-order rate laws reported in the literature. These were determined to be 4.5 (liter/gmole)(hr./sup -1/) and 0.03 hr./sup -1/, respectively. However, the rate of formation is much greater (20.4 (liter/gmole) (hr./sup -1/)) when the extraction liquor is recycled. The most likely explanation for this is that the increased total acidity of the recycled liquor compensates for diffusional limitations. A preliminary design and cost analysis of the pretreatment-hydrolysis scheme indicates that glucose can be produced at 10.86 cents per pound, exclusive of straw cost. The corresponding cost per pound of total sugars produced is 5.0 cents. Sensitivity analyses indicate that 42% of the pretreatment cost (excluding hydrolysis) can be attributed to nitric oxide production, and the high yield of sugar obtained is advantageous when considering the cost of straw.

  15. Pretreatment and enzymatic hydrolysis of corn fiber

    Grohmann, K. [USDA Citrus and Subtropical Products Research Labs., Winter Haven, CT (United States); Bothast, R.J. [National Center for Agricultural Utilization Research, Peoria, IL (United States)

    1996-10-01

    Corn fiber is a co-product of the corn wet milling industry which is usually marketed as a low value animal feed ingredient. Approximately 1.2 x 10{sup 6} dry tons of this material are produced annually in the United States. The fiber is composed of kernel cell wall fractions and a residual starch which can all be potentially hydrolyzed to a mixture of glucose, xylose, arabinose and galactose. We have investigated a sequential saccharification of polysaccharides in corn fiber by a treatment with dilute sulfuric acid at 100 to 160{degrees}C followed by partial neutralization and enzymatic hydrolysis with mixed cellulose and amyloglucosidase enzymes at 45{degrees}C. The sequential treatment achieved a high (approximately 85%) conversion of all polysaccharides in the corn fiber to monomeric sugars, which were in most cases fermentable to ethanol by the recombinant bacterium Escherichia coli KOll.

  16. Enzymatic hydrolysis of potato pulp

    Mariusz Lesiecki; Wojciech Białas; Grażyna Lewandowicz

    2012-01-01

    Background. Potato pulp constitutes a complicated system of four types of polysaccharides: cellulose, hemicellulose, pectin and starch. Its composition makes it a potential and attractive raw material for the production of the second generation bioethanol. The aim of this research project was to assess the usefulness of commercial enzymatic preparations for the hydrolysis of potato pulp and to evaluate the effectiveness of hydrolysates obtained in this way as raw materials for ethanol ferment...

  17. Hydrolysis of starch by sorghum malt for maltodextrin production [abstract

    Thonart, P.

    2010-01-01

    Full Text Available Maltodextrin is a mixture of saccharides with a molecular weight between polysaccharides and oligosaccharides with DE lower than 20. Maltodextrin is more soluble in water than native starches, also is cheaper in comparison with other major edible hydrocolloids. Maltodextrin is obtained by moderate enzymatic or acidic hydrolysis of starch. The hydrolysis of starch, catalyzed by amylases, is the most important commercial enzyme process. The hydrolyzed products are widely applied in food, paper and textile industries. Because of the increasing demand for these enzymes in various industries, there is enormous interest in developing enzymes with better properties, such as raw starch-degrading amylases suitable for industrial applications and their cost-effective production techniques. Sorghum (Sorghum bicolor is a widely grown crop in Africa. Obtaining enzymes from sorghum requires a transformation. The objective of this study was application of sorghum amylase for maltodextrin. Sorghum seeds were supplied by the ISRA (Bambey, Senegal. Seeds were germinated in the laboratory at 30°C for 72 h and the sorghum malt was dried at 40°C for 48 h. Corn starch (from Roquette, France hydrolysis was assayed in a bioreactor of 2 l at a temperature of 65°C gently stirred. Raw starch was slurried in water (30% w/v and sorghum malt was introduced, chloride calcium was added, pH was adjusted to 6. Maltodextrin was characterized in term of the dextrose equivalent (DE during the hydrolysis. The yield of hydrolysis was evaluated by soluble solids (° BRIX at different hydrolysis time. The glucose concentration released was measured by DNS method (Miller method.

  18. CFD simulation of transient stage of continuous countercurrent hydrolysis of canola oil

    Wang, Weicheng

    2012-08-01

    Computational Fluid Dynamic (CFD) modeling of a continuous countercurrent hydrolysis process was performed using ANSYS-CFX. The liquid properties and flow behavior such as density, specific heats, dynamic viscosity, thermal conductivity, and thermal expansivity as well as water solubility of the hydrolysis components triglyceride, diglyceride, monoglyceride, free fatty acid, and glycerol were calculated. Chemical kinetics for the hydrolysis reactions were simulated in this model by applying Arrhenius parameters. The simulation was based on actual experimental reaction conditions including temperature and water-to-oil ratio. The results not only have good agreement with experimental data but also show instantaneous distributions of concentrations of every component in hydrolysis reaction. This model provided visible insight into the continuous countercurrent hydrolysis process. © 2012 Elsevier Ltd.

  19. Product sampling during transient continuous countercurrent hydrolysis of canola oil and development of a kinetic model

    Wang, Weicheng

    2013-11-01

    A chemical kinetic model has been developed for the transient stage of the continuous countercurrent hydrolysis of triglycerides to free fatty acids and glycerol. Departure functions and group contribution methods were applied to determine the equilibrium constants of the four reversible reactions in the kinetic model. Continuous countercurrent hydrolysis of canola oil in subcritical water was conducted experimentally in a lab-scale reactor over a range of temperatures and the concentrations of all neutral components were quantified. Several of the rate constants in the model were obtained by modeling this experimental data, with the remaining determined from calculated equilibrium constants. Some reactions not included in the present, or previous, hydrolysis modeling efforts were identified from glycerolysis kinetic studies and may explain the slight discrepancy between model and experiment. The rate constants determined in this paper indicate that diglycerides in the feedstock accelerate the transition from "emulsive hydrolysis" to "rapid hydrolysis". © 2013 Elsevier Ltd.

  20. 杨木废弃物稀酸水解预处理条件的响应面优化%Optimization of Dilute-sulfuric Acid Pretreatment of Poplar Residues by Using Response Surface Design

    房桂干; 刘姗姗; 沈葵忠

    2014-01-01

    The dilute acid hydrolysis was applied to the poplar residues conversion,and the polysaccharides conversion rate was figured out for the assessment of conversion efficiency. Several parameters concerned with the conversion efficiency,such as bio-mass substrate size,dosage of acid,hydrolysis pressure( or temperature)and reaction time were investigated. The response surface experimental design was used to optimize the dilute acid hydrolysis conditions. It was proposed that proper particle sizes were 0. 075 to 0. 096 mm and the optimal conditions for the dilute sulfuric acid hydrolysis were illustrated as the solid to liquid ratio of 1:10,temperature of 158℃,reaction time of 5 min,and the fraction of sulfuric acid of 2. 5%. Under the optimal conditions,the polysaccharides conversion rate was up to 59. 23%. The HPLC analysis of hydrolyzates showed that the main component was xylose(29. 897 g/L)with a content of 64. 8% in total sugar amount,and the second one was glucose(8. 748 g/L)with a content of 18. 9%. Less monosaccharides further degraded in the dilute acid hydrolysis. The SEM observation and XRD analysis of substrate samples before and after the dilute acid hydrolysis showed that the fiber structure of the hydrolysis residue was damaged obviously,and the crystallinity decreased from 57. 45% of the raw material to 47. 37% of the hydrolysis residue. It could be expected that the hydrolysis residue be utilized to make bioethanol by enzymatic hydrolysis and fermentation.%以聚糖类转化率为考核指标,探讨了杨木废弃物稀酸水解预处理物料的适宜颗粒尺寸范围,并用响应面实验设计优化了稀酸水解条件。结果表明,稀酸水解预处理物料的适宜颗粒尺寸为0.075~0.096 mm,稀硫酸水解的优化工艺条件为:固液比1:10,温度158℃,时间5 min,硫酸质量分数2.5%。在此优化条件下,聚糖类转化率为59.23%。稀酸水解液的高效液相色谱分析表明,水

  1. Escherichia coli DnaB Helicase–DnaC Protein Complex: Allosteric Effects of the Nucleotides on the Nucleic Acid Binding and the Kinetic Mechanism of NTP Hydrolysis. 3†

    Roychowdhury, Anasuya; Szymanski, Michal R.; Jezewska, Maria J.; Bujalowski, Wlodzimierz

    2009-01-01

    Allosteric interactions between the DNA- and NTP-binding sites of the Escherichia coli DnaB helicase engaged in the DnaB–DnaC complex and the mechanism of NTP hydrolysis by the complex have been examined using the fluorescence titration, analytical ultracentrifugation, and rapid quench-flow technique. Surprisingly, the ssDNA affinity of the DnaB–DnaC complex is independent of the structure of the phosphate group of the cofactor bound to the helicase. Thus, the DnaC protein eliminates the anta...

  2. The Oxidatively-Induced DNA Lesions 8,5′-Cyclo-2′-Deoxyadenosine and 8-Hydroxy-2′-Deoxyadenosine Are Strongly Resistant to Acid-Induced Hydrolysis of the Glycosidic Bond

    Theruvathu, Jacob A.; Jaruga, Pawel; Dizdaroglu, Miral; Brooks, PJ

    2007-01-01

    The 8,5’-cyclopurine-2’-deoxynucleosides (cPu) are unique oxidatively-induced DNA lesions in that they are specifically repaired by NER. In the absence of NER, a possible mechanism for cPu removal is spontaneous glycosidic bond hydrolysis followed by enzymic processing. Such a mechanism could be significant if the glycosidic bond in cPu were substantially destabilized, as shown for other DNA lesions. Therefore, we investigated the stability of the glycosidic bond in a cPu, 8,5’(S)-cyclo-dA (S...

  3. Simultaneous pretreatment and enzymatic hydrolysis of forage biomass

    Henk, L.; Linden, J.C. [Colorado State Univ., Fort Collins, CO (United States)

    1993-12-31

    Sweet sorghum is an attractive fermentation feedstock because as much as 40% of the dry weight consists of readily femented sugars such as sucrose, glucose and frutose. Cellulose and hemicellulose comprise another 50%. However, if this material is to be used a year-round feedstock for ethanol production, a stable method of storage must be developed to maintain the sugar content. A modified version of the traditional ensiling process is made effective by the addition of cellulolytic/hemicellulolytic enzymes and lactic acid bacteria to freshly chopped sweet sorghum prior to the production of silage. In situ hydrolysis of cellulose and hemicellulose occurs concurrently with the acidic ensiling fementation. By hydolyzing the acetyl groups using acetyl xylan esterase and 3-0-methyl glucuronyl side chains using pectinase from hemicellulose, cellulose becomes accessible to hydrolysis by cellulase, both during in situ ensiling with enzymes and in the simultaneous saccharification and fermentation (SSF) to ethanol.

  4. A DFT investigation of methanolysis and hydrolysis of triacetin

    Limpanuparb, Taweetham; Tantirungrotechai, Yuthana; 10.1016/j.theochem.2010.05.022

    2012-01-01

    The thermodynamic and kinetic aspects of the methanolysis and hydrolysis reactions of glycerol triacetate or triacetin, a model triacylglycerol compound, were investigated by using Density Functional Theory (DFT) at the B3LYP/6-31++G(d,p) level of calculation. Twelve elementary steps of triacetin methanolysis were studied under acid-catalyzed and base-catalyzed conditions. The mechanism of acid-catalyzed methanolysis reaction which has not been reported yet for any esters was proposed. The effects of substitution, methanolysis/hydrolysis position, solvent and face of nucleophilic attack on the free energy of reaction and activation energy were examined. The prediction confirmed the facile position at the middle position of glycerol observed by NMR techniques. The calculated activation energy and the trends of those factors agree with existing experimental observations in biodiesel production.

  5. The effect of monosaccharide sugars and pyruvate on the differentiation and metabolism of sheep granulosa cells in vitro.

    Campbell, B K; Onions, V; Kendall, N R; Guo, L; Scaramuzzi, R J

    2010-10-01

    The objective of this study was to investigate the effect of three monosaccharides or pyruvate on the ability of gonadotrophins to induce cellular proliferation and differentiation of cultured sheep granulosa cells. Lactate production and levels of mRNA expression for the glucose transporters SLC2A1, SLC2A4, SLC2A5 and SLC2A8 were also determined. No energy source in the culture media reduced cell number (50%) and oestradiol (E(2)) production. Dose and type of monosaccharide had a highly significant (Pculture in the presence of fructose and glucose. These data show that glucose, metabolised under anoxic conditions to lactate, is the preferred energy substrate to support the gonadotrophin-induced differentiation of ovine granulosa cells in vitro, and that fructose and pyruvate, but not galactose, are alternative energy substrates despite marked differences in the way these substrates are metabolised. PMID:20634389

  6. Efficient Phagocytosis Requires Triacylglycerol Hydrolysis by Adipose Triglyceride Lipase*

    Chandak, Prakash G.; Radović, Branislav; Aflaki, Elma; Kolb, Dagmar; Buchebner, Marlene; Fröhlich, Eleonore; Magnes, Christoph; Sinner, Frank; Haemmerle, Guenter; Zechner, Rudolf; Tabas, Ira; Levak-Frank, Sanja; Kratky, Dagmar

    2010-01-01

    Macrophage phagocytosis is an essential biological process in host defense and requires large amounts of energy. To date, glucose is believed to represent the prime substrate for ATP production in macrophages. To investigate the relative contribution of free fatty acids (FFAs) in this process, we determined the phagocytosis rates in normal mouse macrophages and macrophages of adipose triglyceride lipase (ATGL)-deficient mice. ATGL was shown to be the rate-limiting enzyme for the hydrolysis of...

  7. Synthesis of zirconia colloidal dispersions by forced hydrolysis

    JELENA P. MARKOVIC

    2006-06-01

    Full Text Available Different zirconia colloidal dispersions (sols were prepared from zirconyl oxynitrate and zirconyl oxychloride solutions by forced hydrolysis. Vigorously stirred acidic solutions of these salts were refluxed at 102 oC for 24 h. Characterization of the obtained sols (pH, solid phase content, crystal structure was performed by potentiometric, XRD, TGA/DTA and SEM measurements. The prepared sols contained almost spherical monoclinic hydrated zirconia particles 7–10 nm in diameter.

  8. Combination effect of pH and acetate on enzymatic cellulose hydrolysis

    ROMSAIYUD Angsana; SONGKASIRI Warinthom; NOPHARATANA Annop; CHAIPRASERT Pawinee

    2009-01-01

    The productivity and efficiency of cellulase are significant in cellulose hydrolysis. With the accumulation of volatile fatty acids (VFAs), the pH value in anaerobic digestion system is reduced. Therefore, this study will find out how the pH and the amount of acetate influence the enzymatic hydrolysis of cellulose. The effects of pH and acetate on cellulase produced from Bacillus coagulans were studied at various pH 5-8, and acetate concentrations (0-60 mmol/L). A batch kinetic model for enzymatic cellulose hydrolysis was constructed from experimental data and performed. The base hypothesis was as follows: the rates of enzymatic cellulose hydrolysis rely on pH and acetate concentration. The results showed that the suitable pH range for cellulase production and cellulose hydrolysis (represents efficiency of cellulase) was 2.6-7.5, and 5.3-8.3, respectively. Moreover, acetate in the culture medium had an effect on cellulase production (K1= 49.50 mmol/L, n=1.7) less than cellulose hydrolysis (K1=37.85 mmol/L, n=2.0). The results indicated that both the pH of suspension and acidogenic products influence the enzymatic hydrolysis of cellulose in an anaerobic environment. To enhance the cellulose hydrolysis rate, the accumulated acetate concentration should be lower than 25 mmol/L, and pH should be maintained at 7.

  9. In vitro Effect of Monosaccharides on the Virulence of Acanthamoeba Isolated from Patients with Amoebic Keratitis

    Y. Maroofi

    2007-04-01

    Full Text Available Introduction & Objective: Acanthamoeba is free-living amoeba that is found in soil, water, air as well as in human pharynx. Acanthamoeba is causative agent of granulomatose amoebic encephalitis (GAE in immunosuppressed and AIDS individuals and amoebic keratitis in people who use the lens. Pathogenic species of Acanthamoeba have protein receptors named mannose binding protein (MBP. Acanthamoeba via MBP adhere to the glycoproteins included mannose. Acanthamoeba adhesion to the target cells induces a protease secretion is called mannose inducing protein-133 (MIP-133. Exogense mannose can inhibit the adherence of Acanthamoeba; also, it can increase the cytopathatic effect (CPE through increase the secretion of MIP-133. In the present work, the effect of monosaccharides on the virulance of Acanthamoeba isolated from patient with amoebic keratitis, in HeLa cell culture was investigated.Materials & Methods: The isolates were cultured in HeLa cell culture, then 100, 50, 10, 1 and 0.1 mM of galactose, glucose and mannose were added to plates. Plates were observed with invert microscope in 8, 16, 32, 48, and 72 hours after culture.Results: Data implicated that mannose (100 mM showed the highest effect on increasing cytopathy of Acanthamoeba in HeLa cell culture. Meanwhile, galactose (100 mM increased the virulence of Acanthamoeba in the cell culture after 32 hours.Conclusion: Adding mannose and galactose to HeLa cell culture contain Acanthamoeba can increase the virulence of the parasite significantly.

  10. Quantification and monosaccharide composition of hemicelluloses from different plant functional types.

    Schädel, Christina; Blöchl, Andreas; Richter, Andreas; Hoch, Günter

    2010-01-01

    Hemicelluloses are the second most abundant polysaccharide in nature after cellulose. So far, the chemical heterogeneity of cell-wall hemicelluloses and the relatively large sample-volume required in existing methods represent major obstacles for large-scale, cross-species analyses of this important plant compound. Here, we apply a new micro-extraction method to analyse hemicelluloses and the ratio of 'cellulose and lignin' to hemicelluloses in different tissues of 28 plant species comprising four plant functional types (broad-leaved trees, conifers, grasses and herbs). For this study, the fiber analysis after Van Soest was modified to enable the simultaneous quantitative and qualitative measurements of hemicelluloses in small sample volumes. Total hemicellulose concentrations differed markedly among functional types and tissues with highest concentration in sapwood of broad-leaved trees (31% d.m. in Fraxinus excelsior) and lowest concentration between 10 and 15% d.m. in leaves and bark of woody species as well as in roots of herbs. As for total hemicellulose concentrations, plant functional types and tissues exhibited characteristic ratios between the sum of cellulose plus lignin and hemicelluloses, with very high ratios (>4) in bark of trees and low ratios (plant functional types which exhibited characteristic hemicellulose concentrations and monosaccharide patterns. PMID:19926487

  11. Novel monosaccharide fermentation products in Caldicellulosiruptor saccharolyticus identified using NMR spectroscopy

    Isern, Nancy G.; Xue, Junfeng; Rao, Jaya V.; Cort, John R.; Ahring, Birgitte K.

    2013-04-03

    Profiles of metabolites produced by the thermophilic obligately anaerobic cellulose-degrading Gram-positive bacterium Caldicellulosiruptor saccharolyticus DSM 8903 strain following growth on different monosaccharides (D-glucose, D-mannose, L-arabinose, D-arabinose, D-xylose, L-fucose, and D-fucose) as carbon sources revealed several unexpected fermentation products, suggesting novel metabolic capacities and unexplored metabolic pathways in this organism. Both 1H and 13C nuclear magnetic resonance (NMR) spectroscopy were used to determine intracellular and extracellular metabolite profiles. Metabolite profiles were determined from 1-D 1H NMR spectra by curve fitting against spectral libraries provided in Chenomx software. To reduce uncertainties due to unassigned, overlapping, or poorly-resolved peaks, metabolite identifications were confirmed with 2-D homonuclear and heteronuclear NMR experiments. In addition to expected metabolites such as acetate, lactate, glycerol, and ethanol, several novel fermentation products were identified: ethylene glycol (from growth on D-arabinose, though not L-arabinose), acetoin and 2,3-butanediol (from D-glucose and L-arabinose), and hydroxyacetone (from D-mannose and L-arabinose). Production of ethylene glycol from D-arabinose was particularly notable, with around 10% of the substrate carbon converted into this uncommon fermentation product. The novel products have not previously been reported to be produced by C. saccharolyticus, nor would they be easily predicted from the current genome annotation, and show new potentials for using this strain for production of bioproducts.

  12. Chronic lactose intake modifies the gastric emptying of monosaccharides but not of disaccharides in weanling rats

    E.A.L. da-Costa-Pinto

    1997-06-01

    Full Text Available Ninety-six weanling male Wistar rats were fed for four weeks one of two different chows: a normal rat chow containing 55.5% (w/w starch (control group, N = 48 or a rat chow in which starch was partially replaced by lactose, in such a way that the experimental group (N = 48 received 35.5% (w/w starch and 20% (w/w lactose. The gastric emptying of fluid was then studied by measuring the gastric retention of four test meals containing lactose (5% or 10%, w/v or glucose + galactose (5% or 10%, w/v. Homogenates of the small intestine were assayed for lactase activity. The gastric retention values were obtained 15 min after orogastric infusion of the liquid meals. The median values for gastric retention of the 5% lactose solutions were 37.7% for the control group and 37.0% for the experimental group (P>0.02. For the 10% lactose solution the median values were 51.2% and 47.9% (P>0.02 for the control and experimental groups, respectively. However, for the 2.5% glucose + 2.5% galactose meal the median gastric retention was lower (P0.05. These results suggest that the prolonged ingestion of lactose by young adult rats changes the gastric emptying of a solution containing 5% monosaccharides. This adaptation may reflect the desensitization of intestinal nutrient receptors, possibly by an osmotic effect of lactose present in the chow.

  13. Resolving Structural Isomers of Monosaccharide Methyl Glycosides Using Drift Tube and Traveling Wave Ion Mobility Mass Spectrometry

    Li, Hongli; Giles, Kevin; Bendiak, Brad; Kaplan, Kimberly; Siems, William F.; Hill, Herbert H.

    2012-01-01

    Monosaccharide structural isomers including sixteen methyl-D-glycopyranosides and four methyl-N-acetylhexosamines were subjected to ion mobility measurements by electrospray ion mobility mass spectrometry. Two ion mobility-MS systems were employed: atmospheric pressure drift tube ion mobility time-of-flight mass spectrometry and a Synapt G2 HDMS system which incorporates a low pressure traveling wave ion mobility separator. All the compounds were investigated as [M+Na]+ ions in the positive m...

  14. STP10 encodes a high-affinity monosaccharide transporter and is induced under low-glucose conditions in pollen tubes of Arabidopsis

    Rottmann, Theresa; Zierer, Wolfgang; Subert, Christa; Sauer, Norbert; Stadler, Ruth

    2016-01-01

    Highlight STP10 is part of a high-affinity monosaccharide uptake system in the plasma membrane of pollen tubes of Arabidopsis. It is down-regulated under high-glucose conditions, possibly through the hexokinase pathway.

  15. Enzymatic Hydrolysis of Defatted Mackerel Protein with Low Bitter Taste

    HOU Hu; LI Bafang; ZHAO Xue

    2011-01-01

    Ultrasound-assisted solvent extraction was confirmed as a novel, effective method for separating lipid from mackerel protein, resulting in a degreasing rate (DR) of 95% and a nitrogen recovery (NR) of 88.6%. To obtain protein hydrolysates with high nitrogen recovery and low bitter taste, enzymatic hydrolysis was performed using eight commercially available proteases. It turned out that the optimum enzyme was the 'Mixed enzymes for animal proteolysis'. An enzyme dosage of 4%, a temperature of 50℃, and a hydrolysis time of 300 min were found to be the optimum conditions to obtain high NR (84.28%) and degree of hydrolysis (DH,16.18%) by orthogonal experiments. Glutamic acid was the most abundant amino acid of MDP (defatted mackerel protein) and MDPH (defatted mackerel protein hydrolysates). Compared with the FAO/WHO reference protein, the essential amino acid chemical scores (CS) were greater than 1.0(1.0-1.7) in MDPH, which is reflective of high nutritional value. This, coupled with the light color and slight fishy odor, indicates that MDPH would potentially have a wide range of applications such as nutritional additives, functional ingredients, and so on.

  16. Influence of kaolinite on chiral hydrolysis of methyl dichlorprop enantiomers

    2005-01-01

    The effect of kaolinite on the enzymatic chiral hydrolysis of methyl dichlorprop enantiomers ((R,S)-methyl-2-(2,4-dichlorophenoxy) propanoic acid, 2,4-DPM) was investigated using chiral gas chromatography. Compared with the control without kaolinite, the enantiomeric ratio (ER) increased from 1.35 to 8.33 and the residual ratio of 2,4-DPM decreased from 60.89% to 41.55% in the presence of kaolinite. Kaolinite likely had emotion influence on lipase activity and its enantioselectivity.Moreover, the amount of kaolinite added was also found to be a sensitive factor affecting the enantioselective hydrolysis of 2,4-DPM. Fourier transform infrared (FTIR) spectroscopy studies of the interaction of lipase with kaolinite provided insight into the molecular structure of the complex and offered explanation of the effects of kaolinite on enzymatic hydrolysis of 2,4-DPM.Spectra showed that the effect of kaolinite on the hydrolysis of 2,4-DPM was affected by adsorption of lipase on kaolinite and changes of adsorbed lipase conformation, which led to the modified enantioselectivity.

  17. Analysis of Monosaccharide Composition in Tremella Polysaccharides by Precolumn Derivatization HPLC%柱前衍生化高效液相色谱法分析银耳多糖的单糖组成

    陈英红; 姜翔之; 罗浩铭; 王颖; 姜瑞芝

    2012-01-01

    The reversed-phase high performance liquid chiomatographic (HPLC) method of precolumn-derivatization with l-phenyl-3-methyl-5-pyrazolone was used to establish the optimized separation condition of five traditional monosaccharides. And this optimized separation condition was used to analyze the monosaccharide composition of Tremella polysaccharides. The results of HPLC analysis showed that Tremella polysaccharides consisted of mannose, glucuronic acid, glucose, xylose, fucose with the molar ratio of 3.894:1.264:0.044:1.000: 0.265. The HPLC method is simple, rapid, sensitive, and convenient So it can be applied the quality control of Tremella polysaccharides.%采用1-苯基-3-甲基-5-吡唑啉酮柱前衍生化反相高效液相色谱法,建立了5种常见单糖的最佳分离条件,并将该条件用于银耳多糖的单糖组成分析.银耳多糖中含有甘露糖、葡萄糖醛酸、葡萄糖、木糖、岩藻糖,摩尔比为3.894:1.264:0.044:1.000:0.265.该方法简单、快速、灵敏度高、重现性良好,可用于银耳多糖的质量控制.

  18. Cucumarioside E from the Far Eastern Sea Cucumber Cucumaria japonica (Cucumariidae, Dendrochirotida), New Minor Monosulfated Holostane Triterpene Pentaoside with Glucose as the Second Monosaccharide Residue.

    Silchenko, Alexandra S; Kalinovsky, Anatoly I; Dmitrenok, Pavel S; Kalinin, Vladimir I; Mazeika, Andrey N; Vorobieva, Natalia S; Sanina, Nina M; Kostetsky, Edward Y

    2015-06-01

    New minor triterpene glycoside, cucumarioside E (1) has been isolated from the Far Eastern sea cucumber Cucumaria japonica. The structure of the glycoside was elucidated by 2D-NMR specroscopy and mass-spectrometry. The glycoside has glucose instead of quinovose as the second monosaccharide residue and xylose as third monosaccharide residue that is unique structural feature for triterpene glycosides carbohydrate chains from sea cucumbers belonging to the genus Cucumaria. PMID:26197506

  19. The europium and praseodymium hydrolysis in a 2M NaCl environment

    It was studied the europium and praseodymium hydrolysis in a 2M NaCl ion force environment at 303 K, through two methods: this one extraction with dissolvents (lanthanide-water-NaCl-dibenzoylmethane) in presence of a competitive ligand (diglycolic acid) and that one direct potentiometric titration, of soluble species, followed by a computer refining. The values of one or another techniques of the first hydrolysis constants obtained were similar, which demonstrates that the results are reliable. The set of data obtained on the stability constants of hydrolysis products allowed to draw up the distribution diagrams of chemical species, as europium as praseodymium in aqueous environment. (Author)

  20. A homogalacturonan from the radix of Platycodon grandiflorum and the anti-angiogenesis activity of poly-/oligogalacturonic acids derived therefrom.

    Xu, Yuxia; Dong, Qun; Qiu, Hong; Ma, Chung-Wah; Ding, Kan

    2011-09-27

    A polysaccharide, PGA4-3b, with an average molecular weight of 8.9kDa estimated by high-performance gel-permeation chromatography (HPGPC), was isolated from radix of Platycodon grandiflorum (Jacq.) A. DC. Using monosaccharide analysis, methylation analysis and NMR spectroscopy, PGA4-3b was elucidated to be a linear poly-(1→4)-α-d-galactopyranosyluronic acid that contains no methyl ester groups. Partial acid hydrolysis of PGA4-3b yielded a series of poly- or oligogalacturonic acids with different degrees of polymerization (DP), that is, 4-3bde, 4-3bde-O-1, 4-3bde-O-2, 4-3bde-O-3, and 4-3bde-O-4. Cell tube formation inhibition tests with human microvascular endothelial cells (HMEC) for antiangiogenesis analysis showed that 4-3bde-O-1 and 4-3bde-O-2, the fractions with higher molecular weights, could inhibit tube formation, while the native PGA4-3b and low molecular weight fraction 4-3bde-O-3 and 4-3bde-O4 are ineffective. Moreover, 4-3bde-O-2 with DP 5-10 impaired cell tube formation in a dose-dependent way, suggesting its potential to be developed as an anti-angiogenesis drug. This is the first time oligogalacturonic acids are reported to show an anti-angiogenesis effect. PMID:21700274

  1. Kinetics of enzymatic hydrolysis of methyl ricinoleate

    Neeharika, T. S.V.R.

    2015-12-01

    Full Text Available Ricinoleic acid is an unsaturated hydroxy fatty acid that naturally occurs in castor oil in proportions of up to 85–90%. Ricinoleic acid is a potential raw material and finds several applications in coatings, lubricant formulations and pharmaceutical areas. Enzymatic hydrolysis of castor oil is preferred over conventional hydrolysis for the preparation of ricinoleic acid to avoid estolide formation. A kinetics analysis of the enzymatic hydrolysis of Methyl Ricinoleate in the presence of Candida antarctica Lipase B was carried out in this study by varying reaction temperature (40–60 °C and enzyme concentration (2–5%. The optimal conditions were found to be 6 h reaction time, temperature 60°C, buffer to methyl ricinoleate ratio 2:1(v/w and 4% enzyme concentration to achieve a maximum conversion of 98.5%. A first order reversible reaction kinetic model was proposed to describe this reaction and a good agreement was observed between the experimental data and the model values. The effect of temperature on the forward reaction rate constant was determined by fitting data to the Arrhenius equation. The activation energy for forward reaction was found to be 14.69 KJ·mol−1.El ácido ricinoleico es un hidroxiácido insaturado que se produce naturalmente en el aceite de ricino en proporciones de hasta el 85–90%. El ácido ricinoleico es una materia prima con gran potencial y tiene aplicaciones en revestimientos, formulaciones lubricantes y en áreas farmacéuticas. Para la preparación del ácido ricinoleico se prefiere la hidrólisis enzimática del aceite de ricino a la hidrólisis convencional, para evitar la formación de estólidos. En este estudio se llevó a cabo la cinética de la hidrólisis enzimática del ricinoleato de metilo en presencia de lipasa de Candida antarctica B mediante la variación de la temperatura de reacción (40–60 °C y la concentración de la enzima (2–5%. Las condiciones óptimas de la reacción para

  2. The effect of organosolv pretreatment variables on enzymatic hydrolysis of sugarcane bagasse

    Mesa, Leyanis; González, Erenio; Cara, Cristóbal; M González; Castro, E; Solange I. Mussatto

    2011-01-01

    Sugarcane bagasse pretreated with dilute-acid was submitted to an organosolv ethanol process with NaOH under different operational conditions (pretreatment time, temperature, and ethanol concentration) aiming to maximize the glucose yield in the subsequent enzymatic hydrolysis stage. The different pretreatment conditions resulted in variations in the chemical composition of the solid residue as well as in the glucose recovered by enzymatic hydrolysis. All the studied variables presented signi...

  3. Effect of initial pH on mesophilic hydrolysis and acidification of swine manure

    Lin, Lin; Wan, Chunli; Liu, Xiang; Lee, Duu-Jong; Lei, Zhongfang; Zhang, Yi; Hwa, Tay Joo

    2013-01-01

    Effects of initial pH (3–12) on mesophilic hydrolysis and acidification reactions of swine manure was studied. The initial pH changed the microbial community in the suspension so as to affect hydrolysis and acidification reactions on swine manure. At pH 10–12 the Clostridium alkalicellum and/or Corynebacterium humireducens were enriched and the soluble chemical oxygen demand (SCOD), total volatile fatty acids (VFAs), proteins and carbohydrates from manure were increased in quantities. In part...

  4. Techno-economical evaluation of lignocellulose hydrolysis

    Mirsch, Mikaela

    2014-01-01

    The economic dependency on fossil fuels affects the climate and environment, which drives the fuel research on the largest known renewable carbohydrate source: fermentable sugars from lignocellulose. Several fermentable sugars exist in lignicellulosic materials, but are not accessible for efficient use without pretreatment and hydrolysis. Enzymatic hydrolysis is typically used. Enzymatic hydrolysis has a high selectivity and is performed in mild conditions, but the cost of...

  5. Enzymatic hydrolysis of plant extracts containing inulin

    Guiraud, J.P.; Galzy, P.

    1981-10-01

    Inulin-rich extracts of chicory and Jerusalem artichoke are a good potential source of fructose. Total enzymatic hydrolysis of these extracts can be effected by yeast inulinases (EC 3.2.1.7). Chemical prehydrolysis is unfavourable. Enzymatic hydrolysis has advantages over chemical hydrolysis: it does not produce a dark-coloured fraction or secondary substances. It is possible to envisage the preparation of high fructose syrups using this process. (Refs. 42).

  6. Monosaccharides as silicon chelators: pentacoordinate bis(diolato)(phenyl)silicates with the cis-furanose isomers of common pentoses and hexoses.

    Klüfers, Peter; Kopp, Florian; Vogt, Martin

    2004-09-20

    Five-coordinate phenylsilicates are formed from the reaction of trimethoxy(phenyl)silane with monosaccharides in methanol in the presence of a stoichiometric amount of base. Five complexes have been isolated and characterized with two ketoses and three aldopentoses. The silicon central atom in [K([18]crown-6)][PhSi(beta-D-Fruf 2,3H-2)2].MeOH (1, Fru=fructose) is part of two chelate rings, with the ligands being beta-D-fructofuranose-O2,O3 dianions. The beta-furanose isomer is best suited for silicon ligation because it exhibits a torsion angle close to 0 degrees for the most acidic diol function, thus assuring a flat chelate ring. The same structural principles are also found in [K([18]crown-6)][PhSi(beta-D-Araf1,2H-2)2].2 MeOH (2, Ara=arabinose), [K([18]crown-6)][PhSi(alpha-D-Ribf1,2H-2)2] (3, Rib=ribose), [K([18]crown-6)][PhSi(alpha-D-Xylf1,2H-2)2]. acetone (4, Xyl=xylose), and [K([18]crown-6)][PhSi(alpha-D-Rulf2,3H-2)2] (5, Rul=ribulose). PMID:15378633

  7. SIMULTANEOUS PRETREATMENT OF LIGNOCELLULOSE AND HYDROLYSIS OF STARCH IN MIXTURES TO SUGARS

    Hamzeh Hoseinpour; Keikhosro Karimi; Hamid Zilouei; Taherzadeh, Mohammad J.

    2010-01-01

    Mixtures of starch and lignocelluloses are available in many industrial, agricultural, and municipal wastes and residuals. In this work, dilute sulfuric acid was used for simultaneous pretreatment of lignocellulose and hydrolysis of starch, to obtain a maximum amount of fermentable sugar after enzymatic hydrolysis with cellulase and β-glucosidase. The acid treatment was carried out at 70-150°C with 0-1% (v/v) acid concentration and 5-15% (w/v) solids concentration for 0-40 minutes. Under the ...

  8. Generation of group B soyasaponins I and III by hydrolysis.

    Zhang, Wei; Teng, Su Ping; Popovich, David G

    2009-05-13

    Soyasaponins are a group of oleanane triterpenoids found in soy and other legumes that have been associated with some of the benefits achieved by consuming plant-based diets. However, these groups of compounds are diverse and structurally complicated to chemically characterize, separate from the isoflavones, and isolate in sufficient quantities for bioactive testing. Therefore, the aim of this study was to maximize the extraction of soyasaponins from soy flour, remove isoflavones, separate group B soyasaponins from group A, and produce an extract that contained a majority of non-DDMP (2,3-dihydro-2,5-dihydroxy-6-methyl-4H-pyran-4-one)-conjugated group B soyasaponins I and III. Room temperature extraction in methanol for 24 or 48 h resulted in the maximum recovery of soyasaponins, and Soxhlet extraction resulted in the least. A solid-phase extraction using methanol (45%) was found to virtually eliminate the interfering isoflavones as compared to butanol-water liquid-liquid extraction and ammonium sulfate precipitation, while maximizing saponin recovery. Alkaline hydrolysis in anhydrous methanol produced the maximum amount of soyasaponins I and III as compared to aqueous methanol and acid hydrolysis in both aqueous and anhydrous methanol. The soyasaponin I amount was increased by 175%, and soyasaponin III was increased by 211% after alkaline hydrolysis. Furthermore, after alkaline hydrolysis, a majority of DDMP-conjugated group B soyasaponins such as betag, betaa, gammag, and gammaa transformed into the non-DDMP-conjugated soyasaponins I and III without affecting the glycosidic bond at position C-3 of the ring structure. Therefore, we have developed a method that maximizes the recovery of DDMP-conjugated saponins and uses alkaline hydrolysis to produce an extract containing mainly soyasaponins I and III. PMID:19338335

  9. Chemical recycling of post-consumer PET: structural characterization of terephthalic acid and the effect of Alkaline Hydrolysis at low temperature; Reciclagem quimica do PET pos-consumo: caracterizacao estrutural do acido tereftalico e efeito da hidrolise alcalina em baixa temperatura

    Fonseca, Talitha Granja; Almeida, Yeda Medeiros Bastos de; Vinhas, Gloria Maria, E-mail: gmvinhas@yahoo.com.br [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil). Dept. de Engenharia Quimica

    2014-09-15

    Due to the environmental impact caused by PET packaging disposal, this material recycling has been thoroughly discussed and evaluated. In particular, chemical recycling enables achievement of the monomers that are used in PET resin manufacture: ethylene glycol (EG) and terephthalic acid (PTA). Therefore, studies for this process optimization are important from environmental and economic points of view. The present study investigated certain parameters that influence the depolymerization reaction of PET post-consumer via alkaline hydrolysis in order to obtain PTA. Assays were performed at 70 °C by varying the concentration of sodium hydroxide and the reaction time. The best results were obtained at 10.82 mol L{sup -1} NaOH and 9 h reaction time. Consequently, it was possible to prove this process viability, once analyses by infrared and nuclear magnetic resonance confirmed that PTA was obtained in all reactions performed. (author)

  10. The BEI hydrolysis process and reactor system refined engineering proto-type. BEI pilot-plant improvement and operations demonstrations

    Brelsford, Donald L.

    1999-10-01

    This BEI project involves BEI-HP and RS's applications toward potential commercial validity demonstrations for dilute-acid corn-fiber cellulose-hydrolysis processing with an aim toward fuel ethanol production.

  11. Effect of Limited Hydrolysis on Traditional Soy Protein Concentrate

    Mirjana B. Pesic

    2006-09-01

    Full Text Available The influence of limited proteolysis of soy protein concentrate on proteinextractability, the composition of the extractable proteins, their emulsifying properties andsome nutritional properties were investigated. Traditional concentrate (alcohol leachedconcentrate was hydrolyzed using trypsin and pepsin as hydrolytic agents. Significantdifferences in extractable protein composition between traditional concentrate and theirhydrolysates were observed by polyacrylamide gel electrophoresis (PAGE and by SDSPAGE.All hydrolysates showed better extractability than the original protein concentrate,whereas significantly better emulsifying properties were noticed at modified concentratesobtained by trypsin induced hydrolysis. These improved properties are the result of twosimultaneous processes, dissociation and degradation of insoluble alcohol-induced proteinaggregates. Enzyme induced hydrolysis had no influence on trypsin-inibitor activity, andsignificantly reduced phytic acid content.

  12. Cholinesterase catalyzed hydrolysis of O-acyl derivatives of serotonin

    Hydrolysis of O acyl serotonin derivatives containing the residues of monocarbon dicarbon and amino acids under the effect of horse serum butyryl cholinesterase and bull erythrocytic acetylcholinesterase has been studied. It has been established, that acetylcholinesterase hydrolizes O acetylserotonin only; butyrylcholinesterase hydrolizes all the compounds investigated, except for 5,5'-terephthaloildioxytriptamine. The kinetic parameters of hydrolysis were determined. O acyl serotonin derivatives turned out good substrates of butylrylcholinesterase; serotonin and 5.5'-terephtaloildioxytriptamine are effective competitine inhibitors of the enzyme. Estimating of resistance of O acyl serotonin derivatines to blood cholinesterase effect under physiological conditions shows that the compounds investigated with the exception of 5,5'-terephthaloildioxytriptamine must be quickly hydrolyzed under butyrylcholinesterase action. 5,5'-terephthaloildioxytriptamine is suggested as a radioprotective preparation with the prolonged effect, which agrees with the biological test results

  13. 斑茅酶解转化可发酵单糖的液氨预处理及参数优化%Optimization of liquid ammonia treatment for enzymatic hydrolysis of Saccharum arundinaceum to fermentable sugars

    刘建军; 彭何欢; 赵相君; 程成; 陈峰; 邵千钧

    2013-01-01

    China has abundant available marginal land that can be used for cultivation of lignocellulosic energy plants. Saccharum arundinaceum Retz. is a potential energy crop with both high biomass yield and low soil fertility requirements. It can be planted widely as cellulosic ethanol feedstock in southern China. In the present work Saccharum arundinaceum was pretreated by liquid ammonia treatment (LAT) to overcome biomass recalcitrance, followed by enzymatic hydrolysis. The monosaccharide contents (glucose, xylose, and arabinose) of the enzymatic hydrolysate were determined by high performance liquid chromatography. Experimental results show that the optimal LAT pretreatment conditions were 130 ℃, 2:1 (W/W) ammonia to biomass ratio, 80% moisture content (dry weight basis) and 5 min residence time. Approximately 69.34% glucan and 82.60% xylan were converted after 72 h enzymatic hydrolysis at 1% glucan loading using 15 FPU/(g of glucan) of cellulase. The yields of glucose and xylose were 573% and 1 056% higher than those of the untreated biomass, and the LAT-pretreated substrates obtained an 8-fold higher of total monosaccharide yield than untreated substrates. LAT pretreatment was an effective to increase the enzymatic digestibility of Saccharum arundinaceum compared to acid impregnated steam explosion and similar to that of acid treatment and ammonia fiber expansion treatment.%斑茅(Saccharum arundinaceum Retz.)的生物产量高,对土壤条件要求低,可作为纤维素乙醇生产的原料作物在我国南方地区广泛种植.实验以斑茅为原料,采用液氨预处理法克服其水解顽抗性,并添加纤维素酶进行酶解,运用高效液相色谱(HPLC)测定了酶解液中的单糖含量.实验结果表明在纤维素酶添加量为15FPU/(g当量葡聚糖)、预处理原料含水率为80%、预处理温度为130℃、预处理驻留时间为10 min、液氨与生物质的质量比例为2∶1时,葡聚糖和木聚糖的总转化率分别为69.34

  14. Rate of Hydrolysis of Tertiary Halogeno Alkanes

    Pritchard, D. R.

    1978-01-01

    Describes an experiment to measure the relative rate of hydrolysis of the 2-x-2 methylpropanes, where x is bromo, chloro or iodo. The results are plotted on a graph from which the relative rate of hydrolysis can be deduced. (Author/GA)

  15. Study of Soybean Oil Hydrolysis Catalyzed by Thermomyces lanuginosus Lipase and Its Application to Biodiesel Production via Hydroesterification

    Elisa d'Avila Cavalcanti-Oliveira; Priscila Rufino da Silva; Alessandra Peçanha Ramos; Donato Alexandre Gomes Aranda; Denise Maria Guimarães Freire

    2011-01-01

    The process of biodiesel production by the hydroesterification route that is proposed here involves a first step consisting of triacylglyceride hydrolysis catalyzed by lipase from Thermomyces lanuginosus (TL 100L) to generate free fatty acids (FFAs). This step is followed by esterification of the FFAs with alcohol, catalyzed by niobic acid in pellets or without a catalyst. The best result for the enzyme-catalyzed hydrolysis was obtained under reaction conditions of 50% (v/v) soybean oil and 2...

  16. Aiming for the complete utilization of sugar-beet pulp: Examination of the effects of mild acid and hydrothermal pretreatment followed by enzymatic digestion

    Gruppen Harry

    2011-05-01

    Full Text Available Abstract Background Biomass use for the production of bioethanol or platform chemicals requires efficient breakdown of biomass to fermentable monosaccharides. Lignocellulosic feedstocks often require physicochemical pretreatment before enzymatic hydrolysis can begin. The optimal pretreatment can be different for different feedstocks, and should not lead to biomass destruction or formation of toxic products. Methods We examined the influence of six mild sulfuric acid or water pretreatments at different temperatures on the enzymatic degradability of sugar-beet pulp (SBP. Results We found that optimal pretreatment at 140°C of 15 minutes in water was able to solubilize 60% w/w of the total carbohydrates present, mainly pectins. More severe treatments led to the destruction of the solubilized sugars, and the subsequent production of the sugar-degradation products furfural, hydroxymethylfurfural, acetic acid and formic acid. The pretreated samples were successfully degraded enzymatically with an experimental cellulase preparation. Conclusions In this study, we found that pretreatment of SBP greatly facilitated the subsequent enzymatic degradation within economically feasible time ranges and enzyme levels. In addition, pretreatment of SBP can be useful to fractionate functional ingredients such as arabinans and pectins from cellulose. We found that the optimal combined severity factor to enhance the enzymatic degradation of SBP was between log R'0 = -2.0 and log R'0 = -1.5. The optimal pretreatment and enzyme treatment solubilized up to 80% of all sugars present in the SBP, including ≥90% of the cellulose.

  17. Hydrolysis of Virgin Coconut Oil Using Immobilized Lipase in a Batch Reactor

    Lee Suan Chua

    2012-01-01

    Full Text Available Hydrolysis of virgin coconut oil (VCO had been carried out by using an immobilised lipase from Mucor miehei (Lipozyme in a water-jacketed batch reactor. The kinetic of the hydrolysis was investigated by varying the parameters such as VCO concentration, enzyme loading, water content, and reaction temperature. It was found that VCO exhibited substrate inhibition at the concentration more than 40% (v/v. Lipozyme also achieved the highest production of free fatty acids, 4.56 mM at 1% (w/v of enzyme loading. The optimum water content for VCO hydrolysis was 7% (v/v. A relatively high content of water was required because water was one of the reactants in the hydrolysis. The progress curve and the temperature profile of the enzymatic hydrolysis also showed that Lipozyme could be used for free fatty acid production at the temperature up to 50°C. However, the highest initial reaction rate and the highest yield of free fatty acid production were at 45 and 40°C, respectively. A 100 hours of initial reaction time has to be compensated in order to obtain the highest yield of free fatty acid production at 40°C.

  18. Kinetics Studies on the Hydrolysis Reactions of N-Heteroaryl-4(5)-nitroimidazoles

    There is little study on the hydrolysis reactions of Nheteroarylimidazole derivatives in comparison with those of N-acylimidazoles. Some years ago, we reported the hydrolysis reactions of N-heteroaryl-2-phenylimidazoles, Nfuroyl- 2-phenylimidazole and N-thenoyl-2-phenylimidazole. In the hydrolysis reactions of these compounds, we found a change of the rate dertermining step in acidic regions. These results are very unique even though the feature of hydrolysis reactivity of N-acylimidazole derivatives depends on the structure of N-acylimidazole. But, when one changes the acyl group with the heteroaryl group to the benzoyl group having same leaving group, the pH rate profile for the hydrolysis reaction of N-benzoyl-2-phenylimidazole observed to be related with the diprotonated species of the substrate in acidic region. Finally, in this study, we have found that the rate accelerating effect by the substituent, NO2 group in the leaving group is small. The large kOH value in OH'- catalyzed hydrolysis reaction should be explained that the resonance interaction of the leaving group itself is more important than that between N-1 atom of the imidazole and the carbonyl carbon.

  19. TL and ESR based identification of gamma-irradiated frozen fish using different hydrolysis techniques

    Ahn, Jae-Jun; Akram, Kashif; Shahbaz, Hafiz Muhammad; Kwon, Joong-Ho

    2014-12-01

    Frozen fish fillets (walleye Pollack and Japanese Spanish mackerel) were selected as samples for irradiation (0-10 kGy) detection trials using different hydrolysis methods. Photostimulated luminescence (PSL)-based screening analysis for gamma-irradiated frozen fillets showed low sensitivity due to limited silicate mineral contents on the samples. Same limitations were found in the thermoluminescence (TL) analysis on mineral samples isolated by density separation method. However, acid (HCl) and alkali (KOH) hydrolysis methods were effective in getting enough minerals to carry out TL analysis, which was reconfirmed through the normalization step by calculating the TL ratios (TL1/TL2). For improved electron spin resonance (ESR) analysis, alkali and enzyme (alcalase) hydrolysis methods were compared in separating minute-bone fractions. The enzymatic method provided more clear radiation-specific hydroxyapatite radicals than that of the alkaline method. Different hydrolysis methods could extend the application of TL and ESR techniques in identifying the irradiation history of frozen fish fillets.

  20. Hydrolysis of Olive Oil with Immobilized Lipase in a Tapered Column Reactor

    杨伯伦; 赵国胜; 林宏业

    2003-01-01

    Lipase was immobilized in ion exchange resin and then used in the hydrolysis of olive oil to produce fatty acids and glycerol. The time course of hydrolysis of olive oil was investigated in a stirred tank reactor using both of the free and immobilized lipases to find the yield of activity of immobilized enzyme. Continuous hydrolysis of olive oil was also carried out in a tapered column reactor and a cylindrical column reactor with a bottom ID of 10 mm at different upward flow rates. It can be known from experimental results that the degree of hydrolysis of olive oil in the tapered column reactor is moderately better than that in the cylindrical column reactor, the pressure drop in the tapered column reactor is much smaller than that in the cylindrical column reactor.

  1. Dissecting the effect of chemical additives on the enzymatic hydrolysis of pretreated wheat straw.

    Monschein, Mareike; Reisinger, Christoph; Nidetzky, Bernd

    2014-10-01

    Chemical additives were examined for ability to increase the enzymatic hydrolysis of thermo-acidically pretreated wheat straw by Trichoderma reesei cellulase at 50 °C. Semi-empirical descriptors derived from the hydrolysis time courses were applied to compare influence of these additives on lignocellulose bioconversion on a kinetic level, presenting a novel view on their mechanism of action. Focus was on rate retardation during hydrolysis, substrate conversion and enzyme adsorption. PEG 8000 enabled a reduction of enzyme loading by 50% while retaining the same conversion of 67% after 24h. For the first time, a beneficial effect of urea is reported, increasing the final substrate conversion after 48 h by 16%. The cationic surfactant cetyl-trimethylammonium bromide (CTAB) enhanced the hydrolysis rate at extended reaction time (rlim) by 34% and reduced reaction time by 28%. A combination of PEG 8000 and urea increased sugar release more than additives used individually. PMID:25108473

  2. Comparison of multi-enzyme and thermophilic bacteria on the hydrolysis of mariculture organic waste (MOW).

    Guo, Liang; Sun, Mei; Zong, Yan; Zhao, Yangguo; Gao, Mengchun; She, Zonglian

    2016-01-01

    Mariculture organic waste (MOW) is rich in organic matter, which is a potential energy resource for anaerobic digestion. In order to enhance the anaerobic fermentation, the MOW was hydrolyzed by multi-enzyme and thermophilic bacteria. It was advantageous for soluble chemical oxygen demand (SCOD) release at MOW concentrations of 6 and 10 g/L with multi-enzyme and thermophilic bacteria pretreatments. For multi-enzyme, the hydrolysis was not obvious at substrate concentrations of 1 and 3 g/L, and the protein and carbohydrate increased with hydrolysis time at substrate concentrations of 6 and 10 g/L. For thermophilic bacteria, the carbohydrate was first released at 2-4 h and then consumed, and the protein increased with hydrolysis time. The optimal enzyme hydrolysis for MOW was determined by measuring the changes of SCOD, protein, carbohydrate, ammonia and total phosphorus, and comparing with acid and alkaline pretreatments. PMID:27120653

  3. Comparison of the Hydrolysis Rate of Several Polyol Ester Oils as a Candidate for Environmentally Adapted Synthetic Base Oil

    Han, Du Hee [Korea Research Institute of Chemical Technology, Taejon (Korea); Masuko, Masabumi [Department of Chemical Engineering, Tokyo Institute of Technology, Tokyo (Japan)

    2001-05-01

    The hydrolysis rates of seven kinds of polyol ester base oils [POEs] of different branch shape were investigated by using a simple apparatus under a mild acidic condition. Seven polyol ester base oils were made of poly hydric alcohols of two-four valence, normal or branched fatty acids of different carbon number. p-Toluene sulfonic acid was used as an acid catalyst to accelerate the rate of hydrolysis. Partial esters and fatty acid produced by sequential hydrolysis of POEs were identified, and their concentrations were determined by the calibrated-internal standard method using Gas Chromatography. The rate constants of each step, in sequential hydrolysis, were determined by the least square method from rate equation, and the concentration of each component was compared with one another. It was shown that the rate of hydrolysis of POEs was strongly affected by the molecular structure of fatty acid, a straight chain or a branch chain, and the position of branch. The hydrolysis stability for all the POEs can be reasonably explained by the steric hindrance effect of their molecular structures as water molecule makes an attack on the carbonyl carbon of POEs. 14 refs., 8 figs., 2 tabs.

  4. Monosaccharide anhydrides in atmospheric aerosols - optimization of separation and detection by means of LC-MS technique

    Čmelík, Richard; Coufalík, Pavel; Mikuška, Pavel

    Brno : Institute of Analytical Chemistry AS CR, 2014 - (Foret, F.; Křenková, J.; Drobníková, I.; Guttman, A.; Klepárník, K.), s. 164-166 ISBN 978-80-904959-2-0. [CECE 2014. International Interdisciplinary Meeting on Bioanalysis /11./. Brno (CZ), 20.10.2014-22.10.2014] R&D Projects: GA ČR(CZ) GA14-25558S Institutional support: RVO:68081715 Keywords : monosaccharide anhydrides * LC-MS * aerosols Subject RIV: CB - Analytical Chemistry , Separation http://www.ce-ce.org/CECE2014/CECE%202014%20proceedings_full.pdf

  5. Statistical Evaluation of HTS Assays for Enzymatic Hydrolysis of β-Keto Esters

    Buß, O.; Jager, S.; S-M Dold; S. Zimmermann; Hamacher, K.; Schmitz, K.; J Rudat

    2016-01-01

    β-keto esters are used as precursors for the synthesis of β-amino acids, which are building blocks for some classes of pharmaceuticals. Here we describe the comparison of screening procedures for hydrolases to be used for the hydrolysis of β-keto esters, the first step in the preparation of β-amino acids. Two of the tested high throughput screening (HTS) assays depend on coupled enzymatic reactions which detect the alcohol released during ester hydrolysis by luminescence or absorption. The th...

  6. Hydrolysis of hafnium nitrides and carbides

    Hydrolysis of Hafnium Nitrides and Carbides. The hydrolytic behavior of Hafnium mononitride and monocarbide has been studied and compared with that of Titanium and Zirconium nitrides and carbides. In the case of hydrolysis of HfN the gaseous products were H2, N2 and a small amount of NO, and the liquid product was NH3, as in the case of TiN and ZrN. In isothermal hydrolysis the principal product was NH3 at temperatures lower than 8000C, which was replaced by N2 at temperatures higher than 9000C. In this respect HfN was similar to ZrN, but not to TiN which produced mainly N2 even by hydrolysis at 8000C. The products of hydrolysis of HfC were found to be CO, CO2, H2 and a small amount of CH4 also as in the case of TiC and ZrC. In the isothermal hydrolysis of HfC it was observed that a large amount of H2 evolved at the early stage of the hydrolysis while CO2 continued to evolve with some amount of H2 even after the ceasing of CO evolution. From analysis of the hydrolytic behavior the solid residue after the hydrolysis of HfC was considered to contain some waxes (Csub(n)Hsub(m)). It was suggested that the carbide of the element of smaller atomic number (Ti) would tend to form oxygen compounds (CO, CO2) while the carbide of the element of larger atomic number (Zr, Hf) hydrogen compounds(Csub(n)Hsub(m)), since ThC and UC formed only hydrocarbons and H2 by hydrolysis. This suggestion was also valid to nitride. (auth.)

  7. An Unexpected Hydrolysis Product from Strobilurin Fungicide: Azoxystrobin

    ZHANG Jian-Gong; RUAN Lu-Lu; ZHAO Jin-Hao; ZHU Guo-Nian

    2011-01-01

    The hydrolysis reaction of azoxystrobin in a methanol solution was studied, obtaining a novel compound 3,3-dimethoxy-2-(2-(6-methoxy pyrimidin-4-yloxy)phenyl) propanoic acid. The hydrolysis reaction may be helpful to explaining the degradation mechanism of azoxystrobin in soil or plant, which is also a method for further study on metabolism in vitro. The crystal structure was confirmed by 1H NMR and MS and determined by single-crystal X-ray diffraction. The crystal belongs to the triclinic system, space group P1 with a = 8.5662(2), b = 10.5074(6), c = 10.9849(7), α = 62.8370(10), β = 73.2170(10), γ = 73.3100(2)o, C16H18N2O6, Mr = 334.32, V = 828.09(9)3, Z = 2, Dc = 1.341 g/cm3, F(000) = 352, μ = 0.104 mm-1, S = 1.075, the final R = 0.0665 and wR = 0.1593 for 2083 observed reflections with I 2σ(I) and 220 variable parameters. The crystal analysis shows that the hydrolysis product contains two rings, and a one- dimensional chain structure is formed via the intermolecular hydrogen bond O(1)–H(101)···N(2).

  8. Identification of structurally closely related monosaccharide and disaccharide isomers by PMP labeling in conjunction with IM-MS/MS.

    Yang, Hongmei; Shi, Lei; Zhuang, Xiaoyu; Su, Rui; Wan, Debin; Song, Fengrui; Li, Jinying; Liu, Shuying

    2016-01-01

    It remains particularly difficult for gaining unambiguous information on anomer, linkage, and position isomers of oligosaccharides using conventional mass spectrometry (MS) methods. In our laboratory, an ion mobility (IM) shift strategy was employed to improve confidence in the identification of structurally closely related disaccharide and monosaccharide isomers using IMMS. Higher separation between structural isomers was achieved using 1-phenyl-3-methyl-5-pyrazolone (PMP) derivatization in comparison with phenylhydrazine (PHN) derivatization. Furthermore, the combination of pre-IM fragmentation of PMP derivatives provided sufficient resolution to separate the isomers not resolved in the IMMS. To chart the structural variation observed in IMMS, the collision cross sections (CCSs) for the corresponding ions were measured. We analyzed nine disaccharide and three monosaccharide isomers that differ in composition, linkages, or configuration. Our data show that coexisting carbohydrate isomers can be identified by the PMP labeling technique in conjunction with ion-mobility separation and tandem mass spectrometry. The practical application of this rapid and effective method that requires only small amounts of sample is demonstrated by the successful analysis of water-soluble ginseng extract. This demonstrated the potential of this method to measure a variety of heterogeneous sample mixtures, which may have an important impact on the field of glycomics. PMID:27306514

  9. Catalytic condensation of formaldehyde in aqueous solution initiated by UV irradiation as putative "prebiological" route of the monosaccharides formation

    Pestunova, O. P.; Simonov, A. N.; Matvienko, L. G.; Snytnikov, V. N.; Parmon, V. N.; Snytnikova, O. A.; Tsentalovich, Yu. P.

    The condensation of formaldehyde into higher monosaccharides in aqueous alkaline solutions catalyzed by several metal ions in particular Ca 2 and Mg 2 named as formose reaction is considered as a probable source of carbohydrates in prebiotic conditions Formaldehyde is detected in significant amounts in molecular clouds in space Undoubtedly it was an important gas component of circumsolar protoplanet disk Naturally formaldehyde could be dissolved in water of the Protoearth Calcium and magnesium that are capable of creating an alkaline medium are the abundant elements Thus the basic conditions for the formose reaction and for formation of monosaccharides in nature could be met However the formose reaction is autocatalytic since it can be initiated only in the presence of carbohydrates In spite of the fact that Russian chemist Butlerov discovered the formose reaction almost 150 years ago the reason of autocatalytic character of the process and the mechanism of initiation till now remained not quite clear In our work regular investigation of the mechanism of the formose reaction was carried out Influence of various initiators on reaction kinetics and composition of products was studied The composition of the formose reaction products in presence of different initiators is practically invariable under steady-state conditions and is caused by an aldol condensation of the lowest N 2 - and C 3 -carbohydrates The ability of the C 4 -C 6 sugars to initiate the formose reaction is revealed to correlate with the

  10. Influence of estrogenic pesticides on membrane integrity and membrane transfer of monosaccharide into the human red cell

    Some natural and synthetic estrogens inhibit carrier-mediated transport of glucose into human red blood cells and membrane vesicles from the placenta. The inhibitory action of these estrogens on transport appears to be a direct effect at the membrane and does not involve receptor binding and protein synthesis. It is not clear, however, whether such inhibition is a common feature among estrogenic agents. Several chlorinated hydrocarbon pesticides have been shown to possess estrogenic activity. These pesticides could have inhibitory effects on the human sodium-independent glucose transporter. Owing to the apparent importance of this membrane transporter in human tissues, direct interaction of hormones and xenobiotics with the glucose transporter is of fundamental significance. Some pesticides have been shown to alter membrane structure directly and alter the passive permeability of membranes. Whether the estrogenic pesticides influence passive diffusion of sugars across membranes has not been established. Finally, preliminary observations have suggested that some estrogens and pesticides have lytic effects on intact cells. Consequently, this study focuses on the ability of several estrogens and estrogenic pesticides to disrupt the cell membrane, influence the monosaccharide transporter, and alter the rate of monosaccharide permeation through the membrane by simple diffusion

  11. Role of divalent metal cations in ATP hydrolysis catalyzed by the hepatitis C virus NS3 helicase: Magnesium provides a bridge for ATP to fuel unwinding

    Frick, David N.; Banik, Sukalyani; Rypma, Ryan S.

    2006-01-01

    This study investigates the role of magnesium ions in coupling ATP hydrolysis to the nucleic acid unwinding catalyzed by the NS3 protein encoded by the hepatitis C virus. Analyses of steady-state ATP hydrolysis rates at various RNA and magnesium concentrations were used to determine values for the 15 dissociation constants describing the formation of a productive enzyme-metal-ATP-RNA complex and the 4 rate constants describing hydrolysis of ATP by the possible enzyme-ATP complexes. These valu...

  12. Effect of alkali lignins with different molecular weights from alkali pretreated rice straw hydrolyzate on enzymatic hydrolysis.

    Li, Yun; Qi, Benkun; Luo, Jianquan; Wan, Yinhua

    2016-01-01

    This study investigated the effect of alkali lignins with different molecular weights on enzymatic hydrolysis of lignocellulose. Different alkali lignins fractions, which were obtained from cascade ultrafiltration, were added into the dilute acid pretreated (DAP) and alkali pretreated (AP) rice straws respectively during enzymatic hydrolysis. The results showed that the addition of alkali lignins enhanced the hydrolysis and the enhancement for hydrolysis increased with increasing molecular weights of alkali lignins, with maximum enhancement being 28.69% for DAP and 20.05% for AP, respectively. The enhancement was partly attributed to the improved cellulase activity, and filter paper activity increased by 18.03% when adding lignin with highest molecular weight. It was found that the enhancement of enzymatic hydrolysis was correlated with the adsorption affinity of cellulase on alkali lignins, and the difference in surface charge and hydrophobicity of alkali lignins were responsible for the difference in affinity between cellulase and lignins. PMID:26496216

  13. Ester Prodrugs of Ketoprofen: Synthesis, Hydrolysis Kinetics and Pharmacological Evaluation.

    Dhokchawle, B V; Tauro, S J; Bhandari, A B

    2016-01-01

    The ester prodrugs of ketoprofen with various naturally available antioxidants; menthol, thymol, eugenol, guiacol, vanillin and sesamol have been synthesized by the dicyclohexyl carbodiimide (DCC) coupling method, purified and characterized by spectral data. Further, their, partition coefficients have been determined as well as, hydrolytic studies performed. The synthesized compounds are more lipophilic compared to the parent moieties and are stable in acidic environment, which is a prerequisite for their oral absorption. Under gastric as well as intestinal pH conditions these prodrugs showed variable susceptibility towards hydrolysis. The title compounds when evaluated for anti-inflammatory, analgesic activities and ulcerogenicity, showed improvement over the parent drug. PMID:25894087

  14. Arabidopsis thaliana POLYOL/MONOSACCHARIDE TRANSPORTERS 1 and 2: fructose and xylitol/H+ symporters in pollen and young xylem cells

    Klepek, Yvonne-Simone; Volke, Melanie; Konrad, Kai R.; Wippel, Kathrin; Hoth, Stefan; Hedrich, Rainer; Sauer, Norbert

    2009-01-01

    The genome of Arabidopsis thaliana contains six genes, AtPMT1 to AtPMT6 (Arabidopsis thaliana POLYOL/MONOSACCHARIDE TRANSPORTER 1–6), which form a distinct subfamily within the large family of more than 50 monosaccharide transporter-like (MST-like) genes. So far, only AtPMT5 [formerly named AtPLT5 (At3g18830)] has been characterized and was shown to be a plasma membrane-localized H+-symporter with broad substrate specificity. The characterization of AtPMT1 (At2g16120) and AtPMT2 (At2g16130), ...

  15. HYDROLYSIS OF CHEESEWHEY PROTEINSWITH TRYPSIN, CHYMOTRYPSINAND CARBOXYPEPTIDASEA

    M. F. CUSTÓDIO; A. J. GOULART; D. P. MARQUES; R.C. Giordano; R. L. C. Giordano; R. MONTI

    2009-01-01

    This work presents a method for adding value to cheese whey residues by whey proteins hydrolysis, using trypsin, chymotrypsin and carboxypeptidase A as catalysts. Sweet cheese whey was dialyzed and filtered in kaolin. Lactose and protein contents were analyzed after each step. The activities of bovine pancreas trypsin and chymotrypsin were measured at different pHs and temperatures. The optimal pH for the hydrolysis of whey proteins was 9.0 for both enzymes. Optima te...

  16. Characterisation of antioxidant and antiproliferative acidic polysaccharides from Chinese wolfberry fruits

    He, N.W.; Yang, X.B.; Jiao, Y.D.; Tian, L.; Zhao, Y.

    2012-01-01

    Wolfberry fruit polysaccharides (WFPs) were isolated by hot-water extraction and ethanol precipitation. With HPLC analysis, WFPs were for the first time identified as acidic polysaccharides with galacturonic acid being the main component monosaccharide (24.9%), followed by galactose (21.3%), arabino

  17. Impact of mass transport on the enzymatic hydrolysis of rapeseed oil.

    Schröter, Sandra; Stahmann, Klaus-Peter; Schnitzlein, Klaus

    2015-01-01

    In order to assess the capillary segmented flow reactor as a potentially appropriate reactor device for the enzymatic hydrolysis of vegetable oils, a study was made to reveal the impact of incident mass transfer processes on the hydrolysis rate. As demonstrated by means of experiments performed in a modified Lewis-cell type contactor, which allows the independent adjustment of flow rates for both phases, the enzymatic hydrolysis rate of rapeseed oil is strongly governed by mass transport processes taking place in both phases. In the oil phase, any increase in convective mass transfer results in an enhancement of hydrolysis rate due to facilitated removal of fatty acids from interface layer which is known to inhibit the activity of the enzyme adsorbed at the interface. At asynchronous condition when solely the water phase is agitated, however, convective mass transport in the interface layer has an inverse effect on the hydrolysis rate due to the generation of considerable shear stress in the vicinity of the interface unfavorable for the performance of the enzymes. By operating at synchronous agitation conditions, the shear stress can considerably be reduced. Generally, the positive effect of mass transport in the oil phase compensates the negative one in the aqueous phase thus resulting in an overall increase in hydrolysis rate of 57% with increasing stirrer rates. The results can be applied to the operation of segmented-flow capillary reactors by choosing the oil phase as disperse phase and the water phase as continuous phase, respectively. PMID:25007743

  18. Oxidation-reduction reactions of simple hydroxamic acids and plutonium(IV) ions in nitric acid

    Carrott, M. J.; Fox, O. D.; LeGurun, G.; Jones, C J; Mason, C; Taylor, Robin; Andrieux, Fabrice; Boxall, Colin

    2008-01-01

    Simple hydroxamic acids such as formo- and aceto-hydroxamic acids have been proposed as suitable reagents for the separation of either Pu and/or Np from U in modified or single cycle Purex based solvent extraction processes designed to meet the emerging requirements of advanced fuel cycles. The stability of these hydroxamic acids is dominated by their decomposition through acid hydrolysis. Kinetic studies of the acid hydrolysis of formo- and acetohydroxamic acids are reported in the absence a...

  19. Partial least square modeling of hydrolysis: analyzing the impacts of pH and acetate

    L(U) Fan; HE Pin-jing; SHAO Li-ming

    2006-01-01

    pH and volatile fatty acids both might affect the further hydrolysis of particulate solid waste, which is the limiting-step of anaerobic digestion. To clarify the individual effects of pH and volatile fatty acids, batch experiments were conducted at fixed pH value (pH 5-9) with or without acetate (20 g/L). The hydrolysis efficiencies of carbohydrate and protein were evaluated by carbon and nitrogen content of solids, amylase activity and proteinase activity. The trend of carbohydrate hydrolysis with pH was not affected by the addition of acetate, following the sequence of pH 7>pH 8>pH 9>pH 6>pH 5; but the inhibition of acetate (20 g/L) was obvious by 10%-60 %. The evolution of residual nitrogen showed that the effect of pH on protein hydrolysis was minor, while the acetate was seriously inhibitory especially at alkali condition by 45%-100 %. The relationship between the factors (pH and acetate) and the response variables was evaluated by partial least square modeling (PLS). The PLS analysis demonstrated that the hydrolysis of carbohydrate was both affected by pH and acetate, with pH the more important factor. Therefore, the inhibition by acetate on carbohydrate hydrolysis was mainly due to the corresponding decline of pH, but the presence of acetate species, while the acetate species was the absolutely important factor for the hydrolysis of protein.

  20. The effect of acid hydrolysis on the technological functional properties of pinhão (Araucaria brasiliensis starch Efeito da hidrólise ácida nas propriedades funcionais tecnológicas do amido de pinhão (Araucaria brasiliensis

    Roberta Cruz Silveira Thys

    2013-02-01

    Full Text Available Technological functional properties of native and acid-thinned pinhão (seeds of Araucária angustifolia, Brazilian pine starches were evaluated and compared to those of native and acid-thinned corn starches. The starches were hydrolyzed (3.2 mol.L-1 HCl, 44 ºC, 6 hours and evaluated before and after the hydrolysis reaction in terms of formation, melting point and thermo-reversibility of gel starches, retrogradation (in a 30-day period and measurements every three days, paste freezing and thawing stability (after six freezing and thawing cycles, swelling power, and solubility. The results of light transmittance (% of pastes of native and acid-thinned pinhão starches was higher (lower tendency to retrogradation than that obtained for corn starches after similar storage period. Native pinhão starch (NPS presented lower syneresis than native corn starch (NCS when submitted to freeze-thaw cycles. The acid hydrolysis increased the syneresis of the two native varieties under storage at 5 ºC and after freezing and thawing cycles. The solubility of NPS was lower than that of native corn starch at 25, 50, and 70 ºC. However, for the acid-thinned pinhão starch (APS, this property was significantly higher (p As propriedades funcionais tecnológicas do amido nativo e modificado (hidrólise ácida de pinhão (Araucaria angustifólia foram comparadas às propriedades do amido nativo e ácido hidrolisado de milho. As espécies de amido foram hidrolisadas (3.2 mol.L-1 HCl, 44 ºC, 6 horas e avaliadas, antes e após a reação de hidrólise, de acordo com as análises de formação, fusão e termorreversão do gel, retrogradação (em um período de 30 dias, com medidas a cada 3 dias, estabilidade ao congelamento e descongelamento (após 6 ciclos de congelamento e descongelamento, poder de inchamento e índice de solubilidade. Os resultados obtidos demonstraram que o amido de pinhão apresenta menor tendência à retrogradação quando comparado ao amido

  1. An integrated biohydrogen refinery: Synergy of photofermentation, extractive fermentation and hydrothermal hydrolysis of food wastes

    Redwood, MD; Orozco, RL; Majewski, AJ; Macaskie, LE

    2012-01-01

    An Integrated Biohydrogen Refinery (IBHR) and experimental net energy analysis are reported. The IBHR converts biomass to electricity using hydrothermal hydrolysis, extractive biohydrogen fermentation and photobiological hydrogen fermentation for electricity generation in a fuel cell. An extractive fermentation, developed previously, is applied to waste-derived substrates following hydrothermal pre treatment, achieving 83 99% biowaste destruction. The selective separation of organic acids fro...

  2. Characterization of sugar beet pectic-derived oligosaccharides obtained by enzymatic hydrolysis

    Combo, Agnan Marie Michel; Aguedo, Mario; Quiévy, Nicolas; Danthine, Sabine; Goffin, Dorothée; Jacquet, Nicolas; Blecker, Christophe; Devaux, Jacques; Paquot, Michel

    2013-01-01

    Three pectic oligosaccharides (POS) obtained by enzymatic hydrolysis of sugar beet pectin by combining endopolygalacturonase and pectinmethylesterase, were characterized using high performance liquid chromatography, thermogravimetric analysis, Fourier transform infrared spectroscopy, differential scanning calorimetry and X-ray diffraction. According to chromatographic analyses, POS are composed of mixture of polymers with different molecular weights and different galacturonic acid contents. T...

  3. Sugar loss and enzyme inhibition due to oligosaccharides accumulation during high solids-loading enzymatic hydrolysis

    Oligosaccharide accumulation occurs during high solid loading enzymatic hydrolysis of corn stover (CS) irrespective of using different pretreated corn stover (dilute acid: DA, ionic liquids: IL, ammonia fiber expansion: AFEX and extractive ammonia: EA). The methodology for large-scale separation of ...

  4. Effects of thermo-chemical pre-treatment on anaerobic biodegradability and hydrolysis of lignocellulosic biomass

    Fernandes, T.; Klaasse Bos, G.J.; Zeeman, G.; Sanders, J.P.M.; Lier, van J.B.

    2009-01-01

    The effects of different thermo-chemical pre-treatment methods were determined on the biodegradability and hydrolysis rate of lignocellulosic biomass. Three plant species, hay, straw and bracken were thermo-chemically pre-treated with calcium hydroxide, ammonium carbonate and maleic acid. After pre-

  5. Efficient phagocytosis requires triacylglycerol hydrolysis by adipose triglyceride lipase.

    Chandak, Prakash G; Radovic, Branislav; Aflaki, Elma; Kolb, Dagmar; Buchebner, Marlene; Fröhlich, Eleonore; Magnes, Christoph; Sinner, Frank; Haemmerle, Guenter; Zechner, Rudolf; Tabas, Ira; Levak-Frank, Sanja; Kratky, Dagmar

    2010-06-25

    Macrophage phagocytosis is an essential biological process in host defense and requires large amounts of energy. To date, glucose is believed to represent the prime substrate for ATP production in macrophages. To investigate the relative contribution of free fatty acids (FFAs) in this process, we determined the phagocytosis rates in normal mouse macrophages and macrophages of adipose triglyceride lipase (ATGL)-deficient mice. ATGL was shown to be the rate-limiting enzyme for the hydrolysis of lipid droplet-associated triacylglycerol (TG) in many tissues. Here, we demonstrate that Atgl(-/-) macrophages fail to efficiently hydrolyze cellular TG stores leading to decreased cellular FFA concentrations and concomitant accumulation of lipid droplets, even in the absence of exogenous lipid loading. The reduced availability of FFAs results in decreased cellular ATP concentrations and impaired phagocytosis suggesting that fatty acids must first go through a cycle of esterification and re-hydrolysis before they are available as energy substrate. Exogenously added glucose cannot fully compensate for the phagocytotic defect in Atgl(-/-) macrophages. Hence, phagocytosis was also decreased in vivo when Atgl(-/-) mice were challenged with bacterial particles. These findings imply that phagocytosis in macrophages depends on the availability of FFAs and that ATGL is required for their hydrolytic release from cellular TG stores. This novel mechanism links ATGL-mediated lipolysis to macrophage function in host defense and opens the way to explore possible roles of ATGL in immune response, inflammation, and atherosclerosis. PMID:20424161

  6. INDUCTION OF ENZYME COCKTAILS BY LOW COST CARBON SOURCES FOR PRODUCTION OF MONOSACCHARIDE-RICH SYRUPS FROM PLANT MATERIALS

    Caroline T. Gilleran

    2010-05-01

    Full Text Available The production of cellulases, hemicellulases, and starch-degrading enzymes by the thermophilic aerobic fungus Talaromyces emersonii under liquid state culture on various food wastes was investigated. A comprehensive enzyme screening was conducted, which resulted in the identification of spent tea leaves as a potential substrate for hydrolytic enzyme production. The potent, polysaccharide-degrading enzyme-rich cocktail produced when tea leaves were utilised as sole carbon source was analysed at a protein and mRNA level and shown to exhibit high level production of key cellulose and hemicellulose degrading enzymes. As presented in this paper, the crude enzyme preparation produced after 120 h growth of Talaromyces emersonii on used tea leaves is capable of hydrolysing other lignocellulosic materials into their component monosaccharides, generating high value sugar syrups with a host of industrial applications including conversion to fuels and chemicals.

  7. [Malabsorption of fermentable oligo-, di-, or monosaccharides and polyols (FODMAP) as a common cause of unclear abdominal discomfort].

    Goebel-Stengel, M; Mönnikes, H

    2014-06-01

    Carbohydrate malabsorption is a frequent but underestimated cause of unexplained gastrointestinal symptoms like meteorism, flatulence, pain and diarrhea. By means of hydrogen and/or methane breath test after ingestion of the respective carbohydrate it can be identified and diagnosed easily, fast and reliably by successful nutritional therapy. Besides the well known complaints caused by lactose and fructose malabsorption, other fermentable oligo-, di-, or monosaccharides and polyols (akronym: FODMAP) can cause abdominal discomfort and IBS-like symptoms. In addition to lactose (dairy products) and fructose (apples, pears, mango, watermelon), FODMAPs comprise galactans (legumes), fructans (wheat, onions, garlic, artichoke) and the artificial sweeteners sorbitol, mannitol, maltitol and xylitol (sugar free candy, light products). A general restriction of all FODMAP components can be beneficial in relieving symptoms and improving quality of life in patients with functional gastrointestinal complaints. PMID:24892470

  8. Microwave-Assisted Method for Simultaneous Extraction and Hydrolysis for Determination of Flavonol Glycosides in Ginkgo Foliage Using Brönsted Acidic Ionic-Liquid [HO3S(CH24mim]HSO4 Aqueous Solutions

    Yuangang Zu

    2012-07-01

    Full Text Available The Brönsted acidic ionic-liquid [HO3S(CH24mim] HSO4, a novel dual catalyst–solvent, has been successfully applied in simultaneous microwave-assisted extraction and hydrolysis for the determination of flavonol glycosides in Ginkgo foliage. The parameters, namely the [HO3S(CH24mim]HSO4 concentration, microwave-irradiation power, microwave-irradiation time, and solid–liquid ratio, were optimized. The optimum conditions were: an amount of 1.5 M [HO3S(CH24mim]HSO4, a microwave-irradiation power of 120 W, an irradiation time of 15 min, and a solid–liquid ratio of 1:30 g/mL. Compared with traditional methods the proposed approach demonstrates higher efficiency in a shorter operating time, and is an efficient, rapid, and simple sample preparation method.

  9. HYDROLYSIS OF WHEAT STRAW HEMICELLULOSE AND DETOXIFICATION OF THE HYDROLYSATE FOR XYLITOL PRODUCTION

    Junping Zhuang

    2009-05-01

    Full Text Available Xylitol can be obtained from wheat straw hemicellulose containing a high content of xylan. This study describes a new system of hydrolysis, utilizing a mixed solution of formic acid and hydrochloric acid in which xylan can be hydrolyzed effectively. The hydrolysate contains a high content of formic acid, which markedly inhibits the fermentation. One of the most efficient methods for removing inhibiting compounds is treatment of the hydrolysate with ion-exchange resins. Formate can be removed by a factor of 77.78%, and furfural, acetic acid, phenolic compounds can be removed by 90.36%, 96.29%, and 77.44%, respectively after the hydrolysate has been treated with excess Ca(OH2 and D311 ion-exchange resin. The xylose from the hydrolysis process can be fermented by Candida tropicalis strain (AS2.1776 to produce xylitol with a yield of 41.88 % (xylitol/xylose.

  10. Hydrolysis of Lignocellulose Biomass of Onopordum nervosum Boiss; Hidrolisis acida de la Biomasa Lignocelulosica del cardo Onopordum nervosum Boiss

    Suarez Contreras, C.; Diaz Palma, A.; Paz, M. D.

    1985-07-01

    Hydrolysis of resistant cellulose of Onopordum nervosum Boiss (thistle) to reducing sugars in dilute sulfuric acid in glass ampoules and long residence times has been studied and kinetic parameters determined. The rate of hydrolysis is similar to that of the cellulose of Douglas fir, but comparatively the effect of the acid is more pronounced than temperature. From kinetic data it can be pre ducted the yield and since it can be obtained at least 45% of the potential glucose (48% as reducing sugars) at 190 degree centigree, 1,6% acid and 6,1 min. residence time, it indicates that the continuous acid hydrolysis of thistle may be a process of commercial interest. (Author) 18 refs.

  11. VLDL hydrolysis by hepatic lipase regulates PPARδ transcriptional responses.

    Jonathan D Brown

    Full Text Available BACKGROUND: PPARs (α,γ,δ are a family of ligand-activated transcription factors that regulate energy balance, including lipid metabolism. Despite these critical functions, the integration between specific pathways of lipid metabolism and distinct PPAR responses remains obscure. Previous work has revealed that lipolytic pathways can activate PPARs. Whether hepatic lipase (HL, an enzyme that regulates VLDL and HDL catabolism, participates in PPAR responses is unknown. METHODS/PRINCIPAL FINDINGS: Using PPAR ligand binding domain transactivation assays, we found that HL interacted with triglyceride-rich VLDL (>HDL≫LDL, IDL to activate PPARδ preferentially over PPARα or PPARγ, an effect dependent on HL catalytic activity. In cell free ligand displacement assays, VLDL hydrolysis by HL activated PPARδ in a VLDL-concentration dependent manner. Extended further, VLDL stimulation of HL-expressing HUVECs and FAO hepatoma cells increased mRNA expression of canonical PPARδ target genes, including adipocyte differentiation related protein (ADRP, angiopoietin like protein 4 and pyruvate dehydrogenase kinase-4. HL/VLDL regulated ADRP through a PPRE in the promoter region of this gene. In vivo, adenoviral-mediated hepatic HL expression in C57BL/6 mice increased hepatic ADRP mRNA levels by 30%. In ob/ob mice, a model with higher triglycerides than C57BL/6 mice, HL overexpression increased ADRP expression by 70%, demonstrating the importance of triglyceride substrate for HL-mediated PPARδ activation. Global metabolite profiling identified HL/VLDL released fatty acids including oleic acid and palmitoleic acid that were capable of recapitulating PPARδ activation and ADRP gene regulation in vitro. CONCLUSIONS: These data define a novel pathway involving HL hydrolysis of VLDL that activates PPARδ through generation of specific monounsaturated fatty acids. These data also demonstrate how integrating cell biology with metabolomic approaches provides insight

  12. Hydrolysis and stability of thin pulsed plasma polymerised maleic anhydride coatings

    Drews, Joanna Maria; Launay, Héléne; Hansen, Charles M.;

    2008-01-01

    Abstract The stability of plasma polymerised layers has become important because of their widespread use. This study explored the hydrolysis and degradation stability of coatings of plasma polymerised maleic anhydride. Coatings made with different plasma parameters were exposed to aqueous media of...... different pH as a function of time. ATR-FTIR was used for structure analysis and a toluidine blue staining method allowed quantitative analysis of the hydrolysis of anhydride groups to acid groups. Coatings with constant thickness were obtained at different plasma powers and layers with varying thickness...

  13. Hydrolysis of Virgin Coconut Oil Using Immobilized Lipase in a Batch Reactor

    Lee Suan Chua; Meisam Alitabarimansor; Chew Tin Lee; Ramli Mat

    2012-01-01

    Hydrolysis of virgin coconut oil (VCO) had been carried out by using an immobilised lipase from Mucor miehei (Lipozyme) in a water-jacketed batch reactor. The kinetic of the hydrolysis was investigated by varying the parameters such as VCO concentration, enzyme loading, water content, and reaction temperature. It was found that VCO exhibited substrate inhibition at the concentration more than 40% (v/v). Lipozyme also achieved the highest production of free fatty acids, 4.56 mM at 1% (w/v) of ...

  14. ENZYME-BASED HYDROLYSIS PROCESSES FOR ETHANOL

    Keikhosro Karimi

    2007-11-01

    Full Text Available This article reviews developments in the technology for ethanol produc-tion from lignocellulosic materials by “enzymatic” processes. Several methods of pretreatment of lignocelluloses are discussed, where the crystalline structure of lignocelluloses is opened up, making them more accessible to the cellulase enzymes. The characteristics of these enzymes and important factors in enzymatic hydrolysis of the cellulose and hemicellulose to cellobiose, glucose, and other sugars are discussed. Different strategies are then described for enzymatic hydrolysis and fermentation, including separate enzymatic hydrolysis and fermentation (SHF, simultaneous saccharification and fermentation (SSF, non-isothermal simultaneous saccharification and fermentation (NSSF, simultaneous saccharification and co-fermentation (SSCF, and consolidated bioprocessing (CBP. Furthermore, the by-products in ethanol from lignocellulosic materials, wastewater treatment, commercial status, and energy production and integration are reviewed.

  15. ENZYMATIC HYDROLYSIS OF AGRICULTURAL LIGNOCELLULOSIC BIOMASS

    S. STRAVA

    2009-05-01

    Full Text Available The yield, productivity and cost for the enzymatic hydrolysis of cellulose to glucoseare crucial for the production of second generation ethanol. In the first study wehave evaluated the activity of several commercial cellulolytic enzymes and a crudeextract of a local strain of Trichoderma viride. The load used was 15 U ofcellulase/gram cellulose and 90 U of cellobiase/gram cellulose. The hydrolysis wascarried out at 50oC and pH 4,8 for 96 hours. The best cellulose hydrolysis yield of58% was obtained with the cocktail formed of crude cellulases from T. virideCMIT3.5 combined with Novozyme 188. This cocktail was used in the second study,when alkaline-steam pretreated wheat straw and corn stover where hydrolyzed at pH4,8 for 96 hours. The temperature was set at 50oC and 40oC. The hydrolysis at lowertemperature was tested for a future experiment of simultaneous hydrolysis andfermentation. An enzymatic assay using glucose-6-phosphate dehydrogenase wasused to determine exclusively glucose, instead of wide-range sugar DNS assay.Reporting to 100 grams of wet pretreated biomass, the following results wereobtained: 14.4 g% glucose for corn stover at 50oC and 13,0 g% at 40oC; 13,1 g%glucose for wheat straw at 50oC and 10.3 g% at 40oC. Considering that wheat strawcontain 36.6% glucose-based carbohydrates, the hydrolysis yields are between39.3% and 28.1%. Further studies, concerning the optimal parameters for cellulasecocktail will be made.

  16. PERUBAHAN STRUKTUR PATI GARUT (Maranta arundinaceae SEBAGAI AKIBAT MODIFIKASI HIDROLISIS ASAM, PEMOTONGAN TITIK PERCABANGAN DAN SIKLUS PEMANASAN-PENDINGINAN [Structure Changes of Arrowroot (Maranta arundinaceae Starch as Influenced by Acid Hydrolysis, Debranching and Autoclaving-Cooling Cycle Modifications

    Didah Nur Faridah1*

    2010-12-01

    Full Text Available The effects of lintnerization (2.2 N HCl, 2 hours, debranching with pullulanase (1.3 U/g and 10.4 U/g starch and/or three-auctoclaving-cooling cycles at 121oC for 15 minutes on the changes of arrowroot starch structures were studied. The structural modifications of amylose and amylopectin were measured by Gel Permiation Chromatography (GPC, and the distribution of degree of polimerization (DP was analyzed by Fluorophore-Assisted Capillary Electrophoresis (FACE. The GPC profile of native starch using Toyopearl HW-65S gel gave mainly two fractions. Fraction I (Fr. I was a high molecular weight component and Fraction II (Fr. II was a low molecular weight component. After acid modification, the carbohydrate content of Fr. II increased while that of Fr. I decreased. The amount of DP of 6 to 8 increased in all modified arrowroot starches. The GPC and FACE analyses showed that all starch modification techniques caused the structural changes of amylopectin molecules to form short chain amyloses.

  17. Enzymatic Hydrolysis Conditions for Egg White Proteins

    Chi, Yujie; Tian, Bo; Sun, Bo; Guo, Mingruo

    2006-01-01

    The enzymatic hydrolysis of proteins in egg white by Alcalase was systematically studied through dual quadratic rotary, orthogonal and regressive design. The optimum conditions of hydrolysis were determined. The results showed that the optimum temperature was 68.5℃, pH 8.21 at the substrate concentration of 5.5%. The regression equation, Y=42.6994+0.3344X1+7.53X2-0.0086X1X2-0.001X21-0.4726X22 (Y-nitrogen recovery rate, NR; X1-enzyme concentration /substrate concentration, E/S; X2-hydrolytic t...

  18. Effect of pretreatment severity in continuous steam explosion on enzymatic conversion of wheat straw: Evidence from kinetic analysis of hydrolysis time courses.

    Monschein, Mareike; Nidetzky, Bernd

    2016-01-01

    Focusing on continuous steam explosion, the influence of pretreatment severity due to varied acid loading on hydrolysis of wheat straw by Trichoderma reesei cellulases was investigated based on kinetic evaluation of the saccharification of each pretreated substrate. Using semi-empirical descriptors of the hydrolysis time course, key characteristics of saccharification efficiency were captured in a quantifiable fashion. Not only hydrolysis rates per se, but also the transition point of their bi-phasic decline was crucial for high saccharification degree. After 48h the highest saccharification was achieved for substrate pretreated at relatively low severity (1.2% acid). Higher severity increased enzyme binding to wheat straw, but reduced the specific hydrolysis rates. Higher affinity of the lignocellulosic material for cellulases does not necessarily result in increased saccharification, probably because of lignin modifications occurring at high pretreatment severities. At comparable severity, continuous pretreatment produced a substrate more susceptible to enzymatic hydrolysis than the batch process. PMID:26496218

  19. Enzymatic hydrolysis of seed proteins. A procedure for evaluating their nutritive value

    A method for the complete hydrolysis of crop proteins using proteolytic enzymes is presented. The proteins from ground seed kernels are extracted with 2.5% SDS (sodium dodecylsulphate) in 0.08N NaOH and treated with a combination of purified pronase E and proteinase K for 50h at 400C in a borate buffer at pH 8.3. The total amino acid spectrum or single amino acids of actual interest can be detected in this hydrolysate. A comparison of the enzymatic procedure with common techniques of protein hydrolysis shows that complete digestion of crop proteins takes place in a wide variety of species. Thin-layer, ion-exchange chromatography was adopted for the determination of lysine, methionine and tryptophan. Results for lysine and tryptophan indicate good agreement with chemical methods, while the values for methionine are better than comparable methods. Hence enzymatic protein hydrolysis combined with thin-layer, ion-exchange chromatography might serve as a suitable tool in mass screening of essential amino acids. The results also indicate that the amines of the dicarboxylic amino acids, which are of minor nutritive value, are the main components of most cereal proteins. Thus we suggest that the evaluation of improved seed proteins should no longer be based on a single, even limiting amino acid, but should include all essential amino acids and their relation to the components of minor value. (author)

  20. Production of fermentable sugars by combined chemo-enzymatic hydrolysis of cellulosic material for bioethanol production

    M. Idrees

    2014-06-01

    Full Text Available To change the recalcitrant nature of the lignocellulosic material for maximum hydrolysis yield, a comprehensive study was done by using sulphuric acid as an exclusive catalyst for the pretreatment process. The enzymatic digestibility of the biomass [Water Hyacinth: Eichhornia crassipes] after pretreatment was determined by measuring the hydrolysis yield of the pretreated material obtained from twenty four different pretreatment conditions. These included different concentrations of sulphuric acid (0.0, 1.0, 2.0 and 3.0%, at two different temperatures (108 and 121 ºC for different residence times (1.0, 2.0 and 3.0h.The highest reducing sugar yield (36.65 g/L from enzymatic hydrolysis was obtained when plant material was pretreated at 121 ºC for 1.0 h residence time using 3.0% (v/v sulphuric acid and at 1:10 (w/v solid to liquid ratio. The total reducing sugars obtained from the two-stage process (pretreatment + enzymatic hydrolysis was 69.6g/L. The resulting sugars were fermented into ethanol by using Saccharomyces cerevisiae. The ethanol yield from the enzymatic hydrolyzate was 95.2% of the theoretical yield (0.51g/g glucose, as determined by GS-MS, and nearly 100% since no reducing sugars were detected in the fermenting media by TLC and DNS analysis.