WorldWideScience

Sample records for spent lignocellulose hydrolysates

  1. Fermentation of lignocellulosic hydrolysates: Inhibition and detoxification

    Palmqvist, E.

    1998-02-01

    The ethanol yield and productivity obtained during fermentation of lignocellulosic hydrolysates is decreased due to the presence of inhibiting compounds, such as weak acids, furans and phenolic compounds produced during hydrolysis. Evaluation of the effect of various biological, physical and chemical detoxification treatments by fermentation assays using Saccharomyces cerevisiae was used to characterise inhibitors. Inhibition of fermentation was decreased after removal of the non-volatile compounds, pre-fermentation by the filamentous fungus Trichoderma reesei, treatment with the lignolytic enzyme laccase, extraction with ether, and treatment with alkali. Yeast growth in lignocellulosic hydrolysates was inhibited below a certain fermentation pH, most likely due to high concentrations of undissociated weak acids. The effect of individual compounds were studied in model fermentations. Furfural is reduced to furfuryl alcohol by yeast dehydrogenases, thereby affecting the intracellular redox balance. As a result, acetaldehyde accumulated during furfural reduction, which most likely contributed to inhibition of growth. Acetic acid (10 g 1{sup -1}) and furfural (3 g 1{sup -1}) interacted antagonistically causing decreased specific growth rate, whereas no significant individual or interaction effects were detected by the lignin-derived compound 4-hydroxybenzoic acid (2 g 1{sup -1}). By maintaining a high cell mass density in the fermentor, the process was less sensitive to inhibitors affecting growth and to fluctuations in fermentation pH, and in addition the depletion rate of bioconvertible inhibitors was increased. A theoretical ethanol yield and high productivity was obtained in continuous fermentation of spruce hydrolysate when the cell mass concentration was maintained at a high level by applying cell recirculation 164 refs, 16 figs, 5 tabs

  2. Detoxification of lignocellulosic hydrolysates using sodium borohydride.

    Cavka, Adnan; Jönsson, Leif J

    2013-05-01

    Addition of sodium borohydride to a lignocellulose hydrolysate of Norway spruce affected the fermentability when cellulosic ethanol was produced using Saccharomyces cerevisiae. Treatment of the hydrolysate with borohydride improved the ethanol yield on consumed sugar from 0.09 to 0.31 g/g, the balanced ethanol yield from 0.02 to 0.30 g/g, and the ethanol productivity from 0.05 to 0.57 g/(L×h). Treatment of a sugarcane bagasse hydrolysate gave similar results, and the experiments indicate that sodium borohydride is suitable for chemical in situ detoxification. The model inhibitors coniferyl aldehyde, p-benzoquinone, 2,6-dimethoxybenzoquinone, and furfural were efficiently reduced by treatment with sodium borohydride, even under mild reaction conditions (20 °C and pH 6.0). While addition of sodium dithionite to pretreatment liquid from spruce improved enzymatic hydrolysis of cellulose, addition of sodium borohydride did not. This result indicates that the strong hydrophilicity resulting from sulfonation of inhibitors by dithionite treatment was particularly important for alleviating enzyme inhibition. PMID:23567704

  3. Succinic Acid Production from Lignocellulosic Hydrolysate by Basfia succiniciproducens

    Salvachua, Davinia; Smith, Holly; St. John, Peter C.; Mohagheghi, Ali; Peterson, Darren J.; Black, Brenna A.; Dowe, Nancy; Beckham, Gregg T.

    2016-08-01

    The production of chemicals alongside fuels will be essential to enhance the feasibility of lignocellulosic biorefineries. Succinic acid (SA), a naturally occurring C4-diacid, is a primary intermediate of the tricarboxylic acid cycle and a promising building block chemical that has received significant industrial attention. Basfia succiniciproducens is a relatively unexplored SA-producing bacterium with advantageous features such as broad substrate utilization, genetic tractability, and facultative anaerobic metabolism. Here B. succiniciproducens is evaluated in high xylose-content hydrolysates from corn stover and different synthetic media in batch fermentation. SA titers in hydrolysate at an initial sugar concentration of 60 g/L reached up to 30 g/L, with metabolic yields of 0.69 g/g, and an overall productivity of 0.43 g/L/h. These results demonstrate that B. succiniciproducens may be an attractive platform organism for bio-SA production from biomass hydrolysates.

  4. Isolation of microorganisms for biological detoxification of lignocellulosic hydrolysates.

    López, M J; Nichols, N N; Dien, B S; Moreno, J; Bothast, R J

    2004-03-01

    Acid pretreatment of lignocellulosic biomass releases furan and phenolic compounds, which are toxic to microorganisms used for subsequent fermentation. In this study, we isolated new microorganisms for depletion of inhibitors in lignocellulosic acid hydrolysates. A sequential enrichment strategy was used to isolate microorganisms from soil. Selection was carried out in a defined mineral medium containing a mixture of ferulic acid (5 mM), 5-hydroxymethylfurfural (5-HMF, 15 mM), and furfural (20 mM) as the carbon and energy sources, followed by an additional transfer into a corn stover hydrolysate (CSH) prepared using dilute acid. Subsequently, based on stable growth on these substrates, six isolates--including five bacteria related to Methylobacterium extorquens, Pseudomonas sp, Flavobacterium indologenes, Acinetobacter sp., Arthrobacter aurescens, and one fungus, Coniochaeta ligniaria--were chosen. All six isolates depleted toxic compounds from defined medium, but only C. ligniaria C8 (NRRL 30616) was effective at eliminating furfural and 5-HMF from CSH. C. ligniaria NRRL 30616 may be useful in developing a bioprocess for inhibitor abatement in the conversion of lignocellulosic biomass to fuels and chemicals. PMID:12908085

  5. Production of Succinic Acid for Lignocellulosic Hydrolysates

    Davison, B.H.; Nghiem, J.

    2002-06-01

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

  6. Identifying inhibitory compounds in lignocellulosic biomass hydrolysates using an exometabolomics approach

    Zha, Y.; Westerhuis, J.A.; Muilwijk, B.; Overkamp, K.M.; Nijmeijer, B.M.; Coulier, L; Smilde, A.K.; Punt, P. J.

    2014-01-01

    Background: Inhibitors are formed that reduce the fermentation performance of fermenting yeast during the pretreatment process of lignocellulosic biomass. An exometabolomics approach was applied to systematically identify inhibitors in lignocellulosic biomass hydrolysates.Results: We studied the composition and fermentability of 24 different biomass hydrolysates. To create diversity, the 24 hydrolysates were prepared from six different biomass types, namely sugar cane bagasse, corn stover, wh...

  7. Lignocellulosic hydrolysate inhibitors selectively inhibit/deactivate cellulase performance.

    Mhlongo, Sizwe I; den Haan, Riaan; Viljoen-Bloom, Marinda; van Zyl, Willem H

    2015-12-01

    In this study, we monitored the inhibition and deactivation effects of various compounds associated with lignocellulosic hydrolysates on individual and combinations of cellulases. Tannic acid representing polymeric lignin residues strongly inhibited cellobiohydrolase 1 (CBH1) and β-glucosidase 1 (BGL1), but had a moderate inhibitory effect on endoglucanase 2 (EG2). Individual monomeric lignin residues had little or no inhibitory effect on hydrolytic enzymes. However, coniferyl aldehyde and syringaldehyde substantially decreased the activity of CBH1 and deactivated BGL1. Acetic and formic acids also showed strong inhibition of BGL1 but not CBH1 and EG2, whereas tannic, acetic and formic acid strongly inhibited a combination of CBH1 and EG2 during Avicel hydrolysis. Diminishing enzymatic hydrolysis is largely a function of inhibitor concentration and the enzyme-inhibitor relationship, rather than contact time during the hydrolysis process (i.e. deactivation). This suggests that decreased rates of hydrolysis during the enzymatic depolymerisation of lignocellulosic hydrolysates may be imparted by other factors related to substrate crystallinity and accessibility. PMID:26453468

  8. Fractionation and Characterization of Brewers' Spent Grain Protein Hydrolysates

    Celus, Inge; BRIJS, Kristof; Delcour, Jan

    2009-01-01

    Protein hydrolysates with a low and high degree of hydrolysis were enzymatically produced from brewers' spent grain (BSG), the insoluble residue of barley malt resulting from the manufacture of wort in the production of beer. To that end, BSG protein concentrate (BPC), prepared by alkaline extraction of BSG and subsequent acid precipitation, was enzymatically hydrolyzed with Alcalase during both 1.7 and 120 min. Because these hydrolysates contained many different peptides, fractionation of th...

  9. Utilization of hydrolysate from lignocellulosic biomass pretreatment to generate electricity by enzymatic fuel cell system.

    Kim, Sung Bong; Kim, Dong Sup; Yang, Ji Hyun; Lee, Junyoung; Kim, Seung Wook

    2016-04-01

    The waste hydrolysate after dilute acid pretreatment (DAP) of lignocellulosic biomass was utilized to generate electricity using an enzymatic fuel cell (EFC) system. During DAP, the components of biomass containing hemicellulose and other compounds are hydrolyzed, and glucose is solubilized into the dilute acid solution, called as the hydrolysate liquid. Glucose oxidase (GOD) and laccase (Lac) were assembled on the electrode of the anode and cathode, respectively. Cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) were measured, and the maximum power density was found to be 1.254×10(3)μW/cm(2). The results indicate that the hydrolysate from DAP is a reliable electrolyte containing the fuel of EFC. Moreover, the impurities in the hydrolysate such as phenols and furans slightly affected the charge transfer on the surface of the electrode, but did not affect the power generation of the EFC system in principal. PMID:26920478

  10. Ethanol production from lignocellulosic hydrolysates using engineered Saccharomyces cerevisiae harboring xylose isomerase-based pathway.

    Ko, Ja Kyong; Um, Youngsoon; Woo, Han Min; Kim, Kyoung Heon; Lee, Sun-Mi

    2016-06-01

    The efficient co-fermentation of glucose and xylose is necessary for the economically feasible bioethanol production from lignocellulosic biomass. Even with xylose utilizing Saccharomyces cerevisiae, the efficiency of the lignocellulosic ethanol production remains suboptimal mainly due to the low conversion yield of xylose to ethanol. In this study, we evaluated the co-fermentation performances of SXA-R2P-E, a recently engineered isomerase-based xylose utilizing strain, in mixed sugars and in lignocellulosic hydrolysates. In a high-sugar fermentation with 70g/L of glucose and 40g/L of xylose, SXA-R2P-E produced 50g/L of ethanol with an yield of 0.43gethanol/gsugars at 72h. From dilute acid-pretreated hydrolysates of rice straw and hardwood (oak), the strain produced 18-21g/L of ethanol with among the highest yield of 0.43-0.46gethanol/gsugars ever reported. This study shows a highly promising potential of a xylose isomerase-expressing strain as an industrially relevant ethanol producer from lignocellulosic hydrolysates. PMID:26990396

  11. Detoxification of dilute acid hydrolysates of lignocellulose with lime.

    Martinez, A; Rodriguez, M E; Wells, M L; York, S W; Preston, J F; Ingram, L O

    2001-01-01

    The hydrolysis of hemicellulose to monomeric sugars by dilute acid hydrolysis is accompanied by the production of inhibitors that retard microbial fermentation. Treatment of hot hydrolysate with Ca(OH)(2) (overliming) is an effective method for detoxification. Using ethanologenic Escherichia coli LY01 as the biocatalyst, our results indicate that the optimal lime addition for detoxification varies and depends on the concentration of mineral acids and organic acids in each hydrolysate. This optimum was shown to be readily predicted on the basis of the titration of hydrolysate with 2 N NaOH at ambient temperature to either pH 7.0 or pH 11.0. The average composition of 15 hydrolysates prior to treatment was as follows (per L): 95.24 +/- 7.29 g sugar, 5.3 +/- 2.99 g acetic acid, 1.305 +/- 0.288 g total furans (furfural and hydroxymethylfurfural), and 2.86 +/- 0.34 g phenolic compounds. Optimal overliming resulted in a 51 +/- 9% reduction of total furans, a 41 +/- 6% reduction in phenolic compounds, and a 8.7 +/- 4.5% decline in sugar. Acetic acid levels were unchanged. Considering the similarity of microorganisms, it is possible that the titration method described here may also prove useful for detoxification and fermentation processes using other microbial biocatalysts. PMID:11312706

  12. Identification of furfural as a key toxin in lignocellulosic hydrolysates and evolution of a tolerant yeast strain.

    Heer, Dominik; Sauer, Uwe

    2008-11-01

    The production of fuel ethanol from low-cost lignocellulosic biomass currently suffers from several limitations. One of them is the presence of inhibitors in lignocellulosic hydrolysates that are released during pre-treatment. These compounds inhibit growth and hamper the production of ethanol, thereby affecting process economics. To delineate the effects of such complex mixtures, we conducted a chemical analysis of four different real-world lignocellulosic hydrolysates and determined their toxicological effect on yeast. By correlating the potential inhibitor abundance to the growth-inhibiting properties of the corresponding hydrolysates, we identified furfural as an important contributor to hydrolysate toxicity for yeast. Subsequently, we conducted a targeted evolution experiment to improve growth behaviour of the half industrial Saccharomyces cerevisiae strain TMB3400 in the hydrolysates. After about 300 generations, representative clones from these evolved populations exhibited significantly reduced lag phases in medium containing the single inhibitor furfural, but also in hydrolysate-supplemented medium. Furthermore, these strains were able to grow at concentrations of hydrolysates that effectively killed the parental strain and exhibited significantly improved bioconversion characteristics under industrially relevant conditions. The improved resistance of our evolved strains was based on their capacity to remain viable in a toxic environment during the prolonged, furfural induced lag phase. PMID:21261870

  13. A process for producing lignocellulosic flocs from NSSC spent liquor.

    Sitter, Thomas; Oveissi, Farshad; Fatehi, Pedram

    2014-03-10

    Presently, the spent liquor (SL) of neutral sulfite semi chemical (NSSC) pulping process is treated in the waste water system. In this work, a new process for isolating lignocelluloses from the SL of an NSSC process is proposed and the effectiveness of this process is evaluated on industrially produced SL. The results showed that under the optimal conditions of pH 6, 30C and 15mg/g poly ethylene imine (PEI) concentration in the SL, a maximum of 37% lignin and 37% hemicelluloses could be removed from SL. Alternatively, the dual system of poly diallyldimethyl ammonium chloride (PDADMAC) and PEI (7.5mg/g each) was evaluated in removing lignocelluloses from the SL; and the results showed that lignin and hemicellulose removals were improved to 47% and 50%, respectively. The turbidity and chemical oxygen demand (COD) of SL, as well as the elemental analysis of generated flocs were also assessed in this work. PMID:24440635

  14. Effect of lignin-derived and furan compounds found in lignocellulosic hydrolysates on biomethane production.

    Barakat, Abdellatif; Monlau, Florian; Steyer, Jean-Philippe; Carrere, Hélène

    2012-01-01

    Hydrolysates resulting from the lignocellulosic biomass pretreatment in bioethanol production may be used to produce biogas. Such hydrolysates are rich in xylose but also contain lignin polymers or oligomers as well as phenolic and furan compounds, such as syringaldehyde, vanillin, HMF, furfural. The aim of this study was to investigate the impact of these byproducts on biomethane production from xylose. The anaerobic digestion of the byproducts alone was also investigated. No inhibition of the anaerobic digestion of xylose was observed and methane was obtained from furans: 430 mL CH(4)/g of furfural and 450 mL CH(4)/g of HMF; from phenolic compounds: 453 mL CH(4)/g of syringaldehyde and 105 mL CH(4)/g of vanillin; and, to a lesser extent, from lignin polymers: from 14 to 46 mL CH(4)/g MV. The use of different natural polymers (lignosulfonates, organosolv and kraft lignins) and synthetic dehydrogenative polymers showed that higher S/G ratios and lower molecular weights in lignin polymers led to greater methane production. PMID:22100239

  15. Death by a thousand cuts: the challenges and diverse landscape of lignocellulosic hydrolysate inhibitors

    JeffScottPiotrowski

    2014-03-01

    Full Text Available Lignocellulosic hydrolysate (LCH inhibitors are a large class of bioactive molecules that arise from pretreatment, hydrolysis, and fermentation of plant biomass. These diverse compounds reduce lignocellulosic biofuel yields by inhibiting cellular processes and diverting energy into cellular responses. LCH inhibitors present one of the most significant challenges to efficient biofuel production by microbes. Development of new strains that lessen the effects of LCH inhibitors is an economically favorable strategy relative to expensive detoxification methods that also can reduce sugar content in deconstructed biomass. Systems biology analyses and metabolic modeling combined with directed evolution and synthetic biology are successful strategies for biocatalyst development, and methods that leverage state-of-the-art tools are needed to overcome inhibitors more completely. This perspective considers the energetic costs of LCH inhibitors and technologies that can be used to overcome their drain on conversion efficiency. We suggest academic and commercial research groups could benefit by sharing data on LCH inhibitors and implementing translational biofuel research.

  16. Enhanced bioproduction of poly-3-hydroxybutyrate from wheat straw lignocellulosic hydrolysates.

    Cesário, M Teresa; Raposo, Rodrigo S; de Almeida, M Catarina M D; van Keulen, Frederik; Ferreira, Bruno S; da Fonseca, M Manuela R

    2014-01-25

    Polyhydroxyalkanoates (PHAs) are bioplastics that can replace conventional petroleum-derived products in various applications. One of the major barriers for their widespread introduction in the market is the higher production costs compared with their petrochemical counterparts. In this work, a process was successfully implemented with high productivity based on wheat straw, a cheap and readily available agricultural residue, as raw material. The strain Burkholderia sacchari DSM 17165 which is able to metabolise glucose, xylose and arabinose, the main sugars present in wheat straw hydrolysates (WSHs), was used. Results in shake flask showed that B. sacchari cells accumulated about 70%gpoly(3-hydroxybutyrate)(P(3HB))/g cell dry weight (CDW) with a yield of polymer on sugars (YP/S) of 0.18g/g when grown on a mixture of commercial C6 and C5 sugars (control), while these values reached about 60%gP(3HB)/g CDW and 0.19g/g, respectively, when WSHs were used as carbon source. In fed-batch cultures carried out in 2L stirred-tank reactors (STRs) on WSH, a maximum polymer concentration of 105 g/L was reached after 61 hours of cultivation corresponding to an accumulation of 72% of CDW. Polymer yield and productivity were 0.22 gP(3HB)/g total sugar consumed and 1.6g/L hour, respectively. The selected feeding strategy successfully overcame the carbon catabolite repression (CCR) phenomenon observed with sugar mixtures containing hexoses and pentoses. This is the first work describing fed-batch cultivations aiming at PHA production using real lignocellulosic hydrolysates. Additionally, the P(3HB) volumetric productivities attained are by far the highest ever achieved on agricultural waste hydrolysates. PMID:24157713

  17. Phenolic compounds: Strong inhibitors derived from lignocellulosic hydrolysate for 2,3-butanediol production by Enterobacter aerogenes.

    Lee, Sang Jun; Lee, Ju Hun; Yang, Xiaoguang; Kim, Sung Bong; Lee, Ja Hyun; Yoo, Hah Young; Park, Chulhwan; Kim, Seung Wook

    2015-12-01

    Lignocellulosic biomass are attractive feedstocks for 2,3-butanediol production due to their abundant supply and low price. During the hydrolysis of lignocellulosic biomass, various byproducts are formed and their effects on 2,3-butanediol production were not sufficiently studied compared to ethanol production. Therefore, the effects of compounds derived from lignocellulosic biomass (weak acids, furan derivatives and phenolics) on the cell growth, the 2,3-butanediol production and the enzymes activity involved in 2,3-butanediol production were evaluated using Enterobacter aerogenes ATCC 29007. The phenolic compounds showed the most toxic effects on cell growth, 2,3-butanediol production and enzyme activity, followed by furan derivatives and weak acids. The significant effects were not observed in the presence of acetic acid and formic acid. Also, feasibility of 2,3-butanediol production from lignocellulosic biomass was evaluated using Miscanthus as a feedstock. In the fermentation of Miscanthus hydrolysate, 11.00 g/L of 2,3-butanediol was obtained from 34.62 g/L of reducing sugar. However, 2,3-butanediol was not produced when the concentration of total phenolic compounds in the hydrolysate increased to more than 1.5 g/L. The present study provides useful information to develop strategies for biological production of 2,3-butanediol and to establish biorefinery for biochemicals from lignocellulosic biomass. PMID:26479290

  18. Kinetic behavior of Candida guilliermondii yeast during xylitol production from Brewer's spent grain hemicellulosic hydrolysate.

    Mussatto, Solange I; Dragone, Giuliano; Roberto, Ins C

    2005-01-01

    Brewer's spent grain, the main byproduct of breweries, was hydrolyzed with dilute sulfuric acid to produce a hemicellulosic hydrolysate (containing xylose as the main sugar). The obtained hydrolysate was used as cultivation medium by Candidaguilliermondii yeast in the raw form (containing 20 g/L xylose) and after concentration (85 g/L xylose), and the kinetic behavior of the yeast during xylitol production was evaluated in both media. Assays in semisynthetic media were also performed to compare the yeast performance in media without toxic compounds. According to the results, the kinetic behavior of the yeast cultivated in raw hydrolysate was as effective as in semisynthetic medium containing 20 g/L xylose. However, in concentrated hydrolysate medium, the xylitol production efficiency was 30.6% and 42.6% lower than in raw hydrolysate and semisynthetic medium containing 85 g/L xylose, respectively. In other words, the xylose-to-xylitol bioconversion from hydrolysate medium was strongly affected when the initial xylose concentration was increased; however, similar behavior did not occur from semisynthetic media. The lowest efficiency of xylitol production from concentrated hydrolysate can be attributed to the high concentration of toxic compounds present in this medium, resulting from the hydrolysate concentration process. PMID:16080723

  19. Succinic acid production by Actinobacillus succinogenes using spent brewer's yeast hydrolysate as a nitrogen source.

    Jiang, Min; Chen, Kequan; Liu, Zhongmin; Wei, Ping; Ying, Hanjie; Chang, Honam

    2010-01-01

    To develop a cost-effective fermentation medium, spent brewer's yeast hydrolysate was evaluated as a nitrogen source for succinic acid production by Actinobacillus succinogenes NJ113 in glucose-containing media. Autolysis and enzymatic hydrolysis were used to hydrolyze the spent brewer's yeast cells to release the nutrients. The results showed that enzymatic hydrolysis was a more effective method due to the higher succinic acid yield and cell growth. However, the incomplete glucose consumption indicated existence of nutrient limitation. Vitamins were subsequently identified as the main limiting factors for succinic acid production using enzymatically hydrolyzed spent brewer's yeast as a nitrogen source. After the addition of vitamins, cell growth and succinic acid concentration both improved. As a result, 15 g/L yeast extract could be successfully replaced with the enzymatic hydrolysate of spent brewer's yeast with vitamins supplementation, resulting in a production of 46.8 g/L succinic acid from 68 g/L glucose. PMID:19418259

  20. Influence of the propagation strategy for obtaining robust Saccharomyces cerevisiae cells that efficiently co-ferment xylose and glucose in lignocellulosic hydrolysates.

    Toms-Pej, Elia; Olsson, Lisbeth

    2015-11-01

    Development of xylose-fermenting yeast strains that are tolerant to the inhibitors present in lignocellulosic hydrolysates is crucial to achieve efficient bioethanol production processes. In this study, the importance of the propagation strategy for obtaining robust cells was studied. Addition of hydrolysate during propagation of the cells adapted them to the inhibitors, resulting in more tolerant cells with shorter lag phases and higher specific growth rates in minimal medium containing acetic acid and vanillin than unadapted cells. Addition of hydrolysate during propagation also resulted in cells with better fermentation capabilities. Cells propagated without hydrolysate were unable to consume xylose in wheat straw hydrolysate fermentations, whereas 40.3% and 97.7% of the xylose was consumed when 12% and 23% (v/v) hydrolysate, respectively, was added during propagation. Quantitative polymerase chain reaction revealed changes in gene expression, depending on the concentration of hydrolysate added during propagation. This study highlights the importance of using an appropriate propagation strategy for the optimum performance of yeast in fermentation of lignocellulosic hydrolysates. PMID:25989314

  1. Engineering and Two-Stage Evolution of a Lignocellulosic Hydrolysate-Tolerant Saccharomyces cerevisiae Strain for Anaerobic Fermentation of Xylose from AFEX Pretreated Corn Stover

    Parreiras, Lucas S.; Breuer, Rebecca J.; Avanasi Narasimhan, Ragothaman; Higbee, Alan J.; La Reau, Alex; Tremaine, Mary; Qin, Li; Willis, Laura B.; Bice, Benjamin D.; Bonfert, Brandi L.; Pinhancos, Rebeca C.; Balloon, Allison J.; Uppugundla, Nirmal; Liu, Tongjun; Li, Chenlin

    2014-01-01

    The inability of the yeast Saccharomyces cerevisiae to ferment xylose effectively under anaerobic conditions is a major barrier to economical production of lignocellulosic biofuels. Although genetic approaches have enabled engineering of S. cerevisiae to convert xylose efficiently into ethanol in defined lab medium, few strains are able to ferment xylose from lignocellulosic hydrolysates in the absence of oxygen. This limited xylose conversion is believed to result from small molecules genera...

  2. Molecular mechanisms of yeast tolerance and in situ detoxification of lignocellulose hydrolysates

    Pretreatment of lignocellulose biomass for biofuels production generates inhibitory compounds that interfere with microbial growth and subsequent fermentation. Remediation of the inhibitors by current physical, chemical, and biological abatement means is economically impractical and overcoming the i...

  3. Lignocellulosic hydrolysates and extracellular electron shuttles for H2 production using co-culture fermentation with Clostridium beijerinckii and Geobacter metallireducens.

    Zhang, Xinyu; Ye, Xiaofeng; Guo, Bin; Finneran, Kevin T; Zilles, Julie L; Morgenroth, Eberhard

    2013-11-01

    A co-culture of Clostridium beijerinckii and Geobacter metallireducens with AH2QDS produced hydrogen from lignocellulosic hydrolysates (biomass of Miscanthus prepared by hydrothermal treatment with dilute acids). This co-culture system enhanced hydrogen production from lignocellulosic hydrolysates by improving substrate utilization and diminishing acetate accumulation, despite the presence of fermentation inhibitors in the hydrolysates. The improvements were greater for xylose-rich hydrolysates. The increase in maximum cumulative hydrogen production for hydrolysates with glucose:xylose mass ratios of 1:0.2, 1:1 and 1:10 g/g was 0%, 22% and 11%, respectively. Alternative extracellular electron shuttles (EES), including indigo dye, juglone, lawsone, fulvic acids and humic acids, were able to substitute for AH2QDS, improving hydrogen production in the co-culture system using xylose as model substrate. Increased utilization of xylose-rich hydrolysates and substitution of alternative EES make the co-culture with EES system a more attractive strategy for industrial biohydrogen production. PMID:23994308

  4. Contribution of PRS3, RPB4 and ZWF1 to the resistance of industrial Saccharomyces cerevisiae CCUG53310 and PE-2 strains to lignocellulosic hydrolysate-derived inhibitors.

    Cunha, Joana T; Aguiar, Tatiana Q; Romaní, Aloia; Oliveira, Carla; Domingues, Lucília

    2015-09-01

    PRS3, RPB4 and ZWF1 were previously identified as key genes for yeast tolerance to lignocellulose-derived inhibitors. To better understand their contribution to yeast resistance to the multiple stresses occurring during lignocellulosic hydrolysate fermentations, we overexpressed these genes in two industrial Saccharomyces cerevisiae strains, CCUG53310 and PE-2, and evaluated their impact on the fermentation of Eucalyptus globulus wood and corn cob hydrolysates. PRS3 overexpression improved the fermentation rate (up to 32%) and productivity (up to 48%) in different hydrolysates. ZWF1 and RPB4 overexpression did not improve the fermentation performance, but their increased expression in the presence of acetic acid, furfural and hydroxymethylfurfural was found to contribute to yeast adaptation to these inhibitors. This study expands our understanding about the molecular mechanisms involved in industrial yeast tolerance to the stresses occurring during lignocellulosic bioethanol production and highlights the importance of selecting appropriate strain backgrounds/hydrolysates combinations when addressing further improvement of these processes. PMID:25974617

  5. A New Approach on Brewer's Spent Grains Treatment and Potential Use as Lignocellulosic Yeast Cells Carriers

    Pires, Eduardo J.; Ruiz, Hctor A.; Teixeira, J. A; Vicente, A.A.

    2012-01-01

    The major objective of this work is to improve the pretreatments of brewers spent grains (BSG) aiming at their use as a source for lignocellulosic yeast carriers (LCYC) production. Therefore, several pretreatments of BSG have been designed aiming at obtaining various yeast carriers, differing on their physicochemical composition. Cellulose, hemicellulose, lignin, fat, protein, and ash content were determined for crude BSG and the LCYCs. The long chain fatty acids profile for the crude BSG wa...

  6. Development of a Saccharomyces cerevisiae Strain with Enhanced Resistance to Phenolic Fermentation Inhibitors in Lignocellulose Hydrolysates by Heterologous Expression of Laccase

    Larsson, Simona; Cassland, Pierre; Jönsson, Leif J

    2001-01-01

    To improve production of fuel ethanol from renewable raw materials, laccase from the white rot fungus Trametes versicolor was expressed under control of the PGK1 promoter in Saccharomyces cerevisiae to increase its resistance to phenolic inhibitors in lignocellulose hydrolysates. It was found that the laccase activity could be enhanced twofold by simultaneous overexpression of the homologous t-SNARE Sso2p. The factors affecting the level of active laccase obtained, besides the cultivation tem...

  7. Direct and simultaneous determination of representative byproducts in a lignocellulosic hydrolysate of corn stover via gas chromatography-mass spectrometry with a Deans switch.

    Zheng, Rongping; Zhang, Hongman; Zhao, Jing; Lei, Mingliu; Huang, He

    2011-08-01

    Pretreatment is one of the most important steps in producing fuel ethanol from lignocellulosic biomass. Simple, fast and accurate quantification of byproducts in lignocellulosic hydrolysates is critical to optimize the pretreatment procedures, but still a challenge. In this paper, a new GC-MS (SIM) method based on a Deans switch has been developed for the determination of byproducts in a corn stover hydrolysate. The Deans switch was incorporated into a hardware system that facilitated the direct aqueous injection (DAI) on GC-MS system. Simultaneous chromatographic separation and quantification of 18 byproducts including four aliphatic acids, five furan derivatives, four phenolic compounds and five others were achieved within 45 min. The detection limits of the presented method for various byproducts were in the range of 0.007-0.832 mg/L. The within-day and between-day precisions of the method were less than 6.0% (RSD, n=6). The accuracy of the method was confirmed with recoveries of 86-128%. A lignocellulosic hydrolysate sample of corn stover was successfully analyzed using this method, with aliphatic acids and furan derivatives accounting for 89.15% of the selected total byproducts. PMID:21722910

  8. Development of a high-throughput method to evaluate the impact of inhibitory compounds from lignocellulosic hydrolysates on the growth of Zymomonas mobilis.

    Franden, Mary Ann; Pienkos, Philip T; Zhang, Min

    2009-12-01

    Overcoming the effects of hydrolysate toxicity towards ethanologens is a key technical barrier in the biochemical conversion process for biomass feedstocks to ethanol. Despite its importance, the complexity of the hydrolysate toxicity phenomena and the lack of systematic studies, analysis and tools surrounding this issue have blocked a full understanding of relationships involving toxic compounds in hydrolysates and their effects on ethanologen growth and fermentation. In this study, we developed a quantitative, high-throughput biological growth assay using an automated turbidometer to obtain detailed inhibitory kinetics for individual compounds present in lignocellulosic biomass hydrolysate. Information about prolonged lag time and final cell densities can also be obtained. The effects of furfural, hydroxymethylfurfural (HMF), acetate and ethanol on growth rate and final cell densities of Zymomonas mobilis 8b on glucose are presented. This method was also shown to be of value in toxicity studies of hydrolysate itself, despite the highly colored nature of this material. Using this approach, we can generate comprehensive inhibitory profiles with many individual compounds and develop models that predict and examine toxic effects in the complex mixture of hydrolysates, leading to the development of improved pretreatment and conditioning processes as well as fermentation organisms. PMID:19683550

  9. Development of a yeast strain for xylitol production without hydrolysate detoxification as part of the integration of co-product generation within the lignocellulosic ethanol process.

    Huang, Chiung-Fang; Jiang, Yi-Feng; Guo, Gia-Luen; Hwang, Wen-Song

    2011-02-01

    The present study verified an applicable technology of xylitol bioconversion as part of the integration of co-product generation within second-generation bioethanol processes. A newly isolated yeast strain, Candida tropicalis JH030, was shown to have a capacity for xylitol production from hemicellulosic hydrolysate without detoxification. The yeast gives a promising xylitol yield of 0.71 g(p) g(s)(-1) from non-detoxified rice straw hydrolysate that had been prepared by the dilute acid pretreatment under severe conditions. The yeast's capacity was also found to be practicable with various other raw materials, such as sugarcane bagasse, silvergrass, napiergrass and pineapple peel. The lack of a need to hydrolysate detoxification enhances the potential of this newly isolated yeast for xylitol production and this, in turn, has the capacity to improve economics of lignocellulosic ethanol production. PMID:21095119

  10. Growth of oleaginous Rhodotorula glutinis in an internal-loop airlift bioreactor by using lignocellulosic biomass hydrolysate as the carbon source.

    Yen, Hong-Wei; Chang, Jung-Tzu

    2015-05-01

    The conversion of abundant lignocellulosic biomass (LCB) to valuable compounds has become a very attractive idea recently. This study successfully used LCB (rice straw) hydrolysate as a carbon source for the cultivation of oleaginous yeast-Rhodotorula glutinis in an airlift bioreactor. The lipid content of 34.3 ± 0.6% was obtained in an airlift batch with 60 g reducing sugars/L of LCB hydrolysate at a 2 vvm aeration rate. While using LCB hydrolysate as the carbon source, oleic acid (C18:1) and linoleic acid (C18:2) were the predominant fatty acids of the microbial lipids. Using LCB hydrolysate in the airlift bioreactor at 2 vvm achieved the highest cell mass growth as compared to the agitation tank. Despite the low lipid content of the batch using LCB hydrolysate, this low cost feedstock has the potential of being adopted for the production of β-carotene instead of lipid accumulation in the airlift bioreactor for the cultivation of R. glutinis. PMID:25454603

  11. Production of modified bentonite via adsorbing lignocelluloses from spent liquor of NSSC process.

    Oveissi, Farshad; Fatehi, Pedram

    2014-12-01

    In this work, the adsorption of lignocelluloses from spent liquor (SL) of neutral sulfite semi chemical (NSSC) pulping process on bentonite was investigated. It was observed that 0.26g/g of lignin and 0.27g/g of hemicelluloses from SL were adsorbed on bentonite under the conditions of 50C, 100rpm and 40g/gSL/bentonite after 3h of treatment. The adsorptions of lignin and hemicellulose were increased to 1.8g/g and 0.45g/g, respectively, via adding 15mg/g of polydiallyldimethylammonium chloride (PDADMAC) in the system of SL/bentonite. The turbidity and COD removals were improved from 69% to 93% and from 25% to 38% by adding PDADMAC to the SL/bentonite system, respectively. The increase in the heating value of bentonite (from 0 to 15.4MJ/kg) confirmed the adsorption of lignocelluloses. The modified bentonite can be used as filler in corrugated medium paper production or as fuel. PMID:25463794

  12. A new approach on Brewer's spent grains treatment and potential use as lignocellulosic yeast cells carriers.

    Pires, Eduardo J; Ruiz, Hctor A; Teixeira, Jos A; Vicente, Antnio A

    2012-06-13

    The major objective of this work is to improve the pretreatments of brewer's spent grains (BSG) aiming at their use as a source for lignocellulosic yeast carriers (LCYC) production. Therefore, several pretreatments of BSG have been designed aiming at obtaining various yeast carriers, differing on their physicochemical composition. Cellulose, hemicellulose, lignin, fat, protein, and ash content were determined for crude BSG and the LCYCs. The long chain fatty acids profile for the crude BSG was also analyzed. Chemical treatments successfully produced several different LCYC based on BSG. The highest cellulose content in LCYC was achieved upon application of caustic (NaOH) treatment during 40 min. Either caustic or combined acid-caustic treatments predominately generated hydrophobic, negatively charged LCYC. The feasibility of using BSG for LCYC production is strengthened by the fact that added-value byproduct can be extracted before the chemical treatments are applied. PMID:22624780

  13. Potential uses of spent mushroom substrate and its associated lignocellulosic enzymes.

    Phan, Chia-Wei; Sabaratnam, Vikineswary

    2012-11-01

    Mushroom industries generate a virtually in-exhaustible supply of a co-product called spent mushroom substrate (SMS). This is the unutilised substrate and the mushroom mycelium left after harvesting of mushrooms. As the mushroom industry is steadily growing, the volume of SMS generated annually is increasing. In recent years, the mushroom industry has faced challenges in storing and disposing the SMS. The obvious solution is to explore new applications of SMS. There has been considerable discussion recently about the potentials of using SMS for production of value-added products. One of them is production of lignocellulosic enzymes such as laccase, xylanase, lignin peroxidase, cellulase and hemicellulase. This paper reviews scientific research and practical applications of SMS as a readily available and cheap source of enzymes for bioremediation, animal feed and energy feedstock. PMID:23053096

  14. Inhibitory action of the toxic compounds present in lignocellulosic hydrolysates on xylose-to-xylitol bioconversion by Candida guilliermondii

    Pereira, Rogério S.; Mussatto, Solange I.; Roberto, Inês Conceição

    2009-01-01

    Lignocellulosic materials represent an abundant and inexpensive source of sugars which can be microbiologically converted to industrial products. However, hydrolysis of lignocellulosic materials for sugars recovery always goes together with the formation of by-products that inhibit the fermentation process. Such by-products include acetic acid, phenolic compounds such as syringaldehyde, ferulic acid, p-hydroxybenzoic acid, and vanillic acid, among others. These toxic compounds can...

  15. Biorefining of lignocellulose : Detoxification of inhibitory hydrolysates and potential utilization of residual streams for production of enzymes

    Cavka, Adnan

    2013-01-01

    Lignocellulosic biomass is a renewable resource that can be utilized for the production of biofuels, chemicals, and bio-based materials. Biochemical conversion of lignocellulose to advanced biofuels, such as cellulosic ethanol, is generally performed through microbial fermentation of sugars generated by thermochemical pretreatment of the biomass followed by an enzymatic hydrolysis of the cellulose. The aims of the research presented in this thesis were to address problems associated with pret...

  16. Production of spent mushroom substrate hydrolysates useful for cultivation of Lactococcus lactis by dilute sulfuric acid, cellulase and xylanase treatment.

    Qiao, Jian-Jun; Zhang, Yan-Fei; Sun, Li-Fan; Liu, Wei-Wei; Zhu, Hong-Ji; Zhang, Zhijun

    2011-09-01

    Spent mushroom substrate (SMS) was treated with dilute sulfuric acid followed by cellulase and xylanase treatment to produce hydrolysates that could be used as the basis for media for the production of value added products. A L9 (3(4)) orthogonal experiment was performed to optimize the acid treatment process. Pretreatment with 6% (w/w) dilute sulfuric acid at 120C for 120 min provided the highest reducing sugar yield of 267.57 g/kg SMS. No furfural was detected in the hydrolysates. Exposure to 20PFU of cellulase and 200 XU of xylanase per gram of pretreated SMS at 40C resulted in the release of 79.85 g/kg or reducing sugars per kg acid pretreated SMS. The dilute sulfuric acid could be recycled to process fresh SMS four times. SMS hydrolysates neutralized with ammonium hydroxide, sodium hydroxide, or calcium hydroxide could be used as the carbon source for cultivation of Lactococcus lactis subsp. lactis W28 and a cell density of 2.910(11)CFU/mL could be obtained. The results provide a foundation for the development of value-added products based on SMS. PMID:21683588

  17. Immunomodulatory potential of a brewers' spent grain protein hydrolysate incorporated into low-fat milk following in vitro gastrointestinal digestion.

    Crowley, Damian; O'Callaghan, Yvonne; McCarthy, Aoife; Connolly, Alan; Piggott, Charles O; FitzGerald, Richard J; O'Brien, Nora M

    2015-01-01

    Brewers' spent grain (BSG) protein rich fraction was previously hydrolysed using Alcalase (U) and three additional fractions were prepared by membrane fractionation; a 5-kDa retentate (U?>?5), a 5-kDa permeate (U?hydrolysate and its associated ultrafiltered fractions can confer anti-inflammatory effects in Jurkat T cells. PMID:26307493

  18. Engineering yeast tolerance to inhibitory lignocellulosic biomass

    Cunha, Joana Filipa Torres Pinheiro; Aguiar, Tatiana Quinta; D. Mendes; Pereira, Francisco B.; Domingues, Lucília

    2013-01-01

    In recent years the necessity for biotechnological manufacturing based on lignocellulosic feedstocks has become evident. However, the pre-treatment step in the production of lignocellulosic bioethanol leads to the accumulation of inhibitory byproducts. Robust second generation bioethanol processes require microorganisms able to ferment these inhibitory lignocellulosic hydrolysates. Significant progress has been made in the understanding of the determinants of yeast tolerance to lignocellulose...

  19. Brewers' spent grain (BSG) protein hydrolysates decrease hydrogen peroxide (H2O2)-induced oxidative stress and concanavalin-A (con-A) stimulated IFN-? production in cell culture.

    McCarthy, Aoife L; O'Callaghan, Yvonne C; Connolly, Alan; Piggott, Charles O; FitzGerald, Richard J; O'Brien, Nora M

    2013-11-01

    The present study investigated the bioactivity of protein hydrolysates and fractionated hydrolysates prepared from brewers' spent grain (BSG) using proteases, including Alcalase 2.4L, Flavourzyme and Corolase PP. Hydrolysates were designated K-Y, including fractionated hydrolysates with molecular weight (m.w.) 5 kDa. Where computable, IC50 values were lower in U937 (1.38-9.78%) than Jurkat T cells (1.15-13.82%). Hydrolysates L, Q and R and fractionated hydrolysates of U and W (5 kDa) significantly (P 5 kDa, V, V > 5 kDa, W, W > 5 kDa significantly (P 5 kDa) possess anti-inflammatory effects. PMID:24113874

  20. A combined adsorption and flocculation process for producing lignocellulosic complexes from spent liquors of neutral sulfite semichemical pulping process.

    Dashtban, Mehdi; Gilbert, Allan; Fatehi, Pedram

    2014-05-01

    The spent liquor (SL) of a neutral sulfite semichemical pulping process contains lignocelluloses that are currently treated in a waste water system. In this work, an adsorption process using activated carbon (AC) was considered for isolating the lignin and hemicelluloses from SL. The maximum adsorptions of 0.9 g/g lignin and 0.43 g/g of hemicelluloses on AC were achieved under the conditions of 30C, pH 7 and 3h with SL/AC weight ratio of 90. The addition of polydiallyldimethylammonium chloride (PDADMAC) to the SL/AC system significantly improved the adsorption of lignin to 2.5 g/g on AC. The molecular weight of PDADMAC considerably affected the results in that the higher MW PDADMAC led to less lignin, but more hemicelluloses, turbidity and chemical oxygen demand removals from the SL. The thermal analysis also revealed that the higher MW PDADMAC generated precipitates with a lower incineration temperature and heating value. PMID:24675396

  1. Second Generation Ethanol Production from Brewers’ Spent Grain

    Rossana Liguori

    2015-03-01

    Full Text Available Ethanol production from lignocellulosic biomasses raises a global interest because it represents a good alternative to petroleum-derived energies and reduces the food versus fuel conflict generated by first generation ethanol. In this study, alkaline-acid pretreated brewers’ spent grain (BSG was evaluated for ethanol production after enzymatic hydrolysis with commercial enzymes. The obtained hydrolysate containing a glucose concentration of 75 g/L was adopted, after dilution up to 50 g/L, for fermentation by the strain Saccharomyces cerevisiae NRRL YB 2293 selected as the best producer among five ethanologenic microorganims. When the hydrolysate was supplemented with yeast extract, 12.79 g/L of ethanol, corresponding to 0.28 g of ethanol per grams of glucose consumed (55% efficiency, was obtained within 24 h, while in the non-supplemented hydrolysate, a similar concentration was reached within 48 h. The volumetric productivity increased from 0.25 g/L·h in the un-supplemented hydrolysate to 0.53 g/L h in the yeast extract supplemented hydrolysate. In conclusion, the strain S. cerevisiae NRRL YB 2293 was shown able to produce ethanol from BSG. Although an equal amount of ethanol was reached in both BSG hydrolysate media, the nitrogen source supplementation reduced the ethanol fermentation time and promoted glucose uptake and cell growth.

  2. Lignosulfonate-mediated cellulase adsorption: enhanced enzymatic saccharification of lignocellulose through weakening nonproductive binding to lignin

    Wang, Zhaojiang; Zhu, JY; Fu, Yingjuan; Qin, Menghua; Shao, Zhiyong; Jiang, Jungang; Yang, Fang

    2013-01-01

    Background Thermochemical pretreatment of lignocellulose is crucial to bioconversion in the fields of biorefinery and biofuels. However, the enzyme inhibitors in pretreatment hydrolysate make solid substrate washing and hydrolysate detoxification indispensable prior to enzymatic hydrolysis. Sulfite pretreatment to overcome recalcitrance of lignocelluloses (SPORL) is a relatively new process, but has demonstrated robust performance for sugar and biofuel production from woody biomass in terms o...

  3. Effect of Lignocellulose Related Compounds on Microalgae Growth and Product Biosynthesis: A Review

    Krystian Miazek

    2014-07-01

    Full Text Available Microalgae contain valuable compounds that can be harnessed for industrial applications. Lignocellulose biomass is a plant material containing in abundance organic substances such as carbohydrates, phenolics, organic acids and other secondary compounds. As growth of microalgae on organic substances was confirmed during heterotrophic and mixotrophic cultivation, lignocellulose derived compounds can become a feedstock to cultivate microalgae and produce target compounds. In this review, different treatment methods to hydrolyse lignocellulose into organic substrates are presented first. Secondly, the effect of lignocellulosic hydrolysates, organic substances typically present in lignocellulosic hydrolysates, as well as minor co-products, on growth and accumulation of target compounds in microalgae cultures is described. Finally, the possibilities of using lignocellulose hydrolysates as a common feedstock for microalgae cultures are evaluated.

  4. Effect of Mechanically Deboned Chicken Meat Hydrolysates on the Physicochemical Properties of Imitation Fish Paste

    Jin, Sang-Keun; Go, Gwang-Woong; Jung, Eun-Young; Lim, Hyun-Jung; Yang, Han-Sul; Park, Jae-Hong

    2014-01-01

    This study investigated on the effects of adding mechanically deboned chicken meat (MDCM) hydrolysates on the quality properties of imitation fish paste (IFP) during storage. IFP was prepared from Alaska Pollack, spent laying hens surimi and protein hydrolysates which were enzymatically extracted from MDCM. The study was designed as a 3×4 factorial design with three MDCM hydrolysate content groups (0%, 0.4%, and 0.8%) and four storage times (0, 2, 4, and 6 weeks). Addition of MDCM hydrolysate...

  5. Fermentative hydrogen production from agroindustrial lignocellulosic substrates

    Reginatto, Valeria; Antônio, Regina Vasconcellos

    2015-01-01

    To achieve economically competitive biological hydrogen production, it is crucial to consider inexpensive materials such as lignocellulosic substrate residues derived from agroindustrial activities. It is possible to use (1) lignocellulosic materials without any type of pretreatment, (2) lignocellulosic materials after a pretreatment step, and (3) lignocellulosic materials hydrolysates originating from a pretreatment step followed by enzymatic hydrolysis. According to the current literature data on fermentative H2 production presented in this review, thermophilic conditions produce H2 in yields approximately 75% higher than those obtained in mesophilic conditions using untreated lignocellulosic substrates. The average H2 production from pretreated material is 3.17 ± 1.79 mmol of H2/g of substrate, which is approximately 50% higher compared with the average yield achieved using untreated materials (2.17 ± 1.84 mmol of H2/g of substrate). Biological pretreatment affords the highest average yield 4.54 ± 1.78 mmol of H2/g of substrate compared with the acid and basic pretreatment - average yields of 2.94 ± 1.85 and 2.41 ± 1.52 mmol of H2/g of substrate, respectively. The average H2 yield from hydrolysates, obtained from a pretreatment step and enzymatic hydrolysis (3.78 ± 1.92 mmol of H2/g), was lower compared with the yield of substrates pretreated by biological methods only, demonstrating that it is important to avoid the formation of inhibitors generated by chemical pretreatments. Based on this review, exploring other microorganisms and optimizing the pretreatment and hydrolysis conditions can make the use of lignocellulosic substrates a sustainable way to produce H2. PMID:26273246

  6. Grass Lignocellulose

    Akin, Danny E.

    Grass lignocelluloses are limited in bioconversion by aromatic constituents, which include both lignins and phenolic acids esters. Histochemistry, ultraviolet absorption microspectrophotometry, and response to microorganisms and specific enzymes have been used to determine the significance of aromatics toward recalcitrance. Coniferyl lignin appears to be the most effective limitation to biodegradation, existing in xylem cells of vascular tissues; cell walls with syringyl lignin, for example, leaf sclerenchyma, are less recalcitrant. Esterified phenolic acids, i.e., ferulic and p-coumaric acids, often constitute a major chemical limitation in nonlignified cell walls to biodegradation in grasses, especially warm-season species. Methods to improve biodegradability through modification of aromatics include: plant breeding, use of lignin-degrading white-rot fungi, and addition of esterases. Plant breeding for new cultivars has been especially effective for nutritionally improved forages, for example, bermudagrasses. In laboratory studies, selective white-rot fungi that lack cellulases delignified the lignocellulosic materials and improved fermentation of residual carbohydrates. Phenolic acid esterases released p-coumaric and ferulic acids for potential coproducts, improved the available sugars for fermentation, and improved biodegradation. The separation and removal of the aromatic components for coproducts, while enhancing the availability of sugars for bioconversion, could improve the economics of bioconversion.

  7. Bioconversion of lignocellulosic residues by Agrocybe cylindracea and Pleurotus ostreatus mushroom fungi--assessment of their effect on the final product and spent substrate properties.

    Koutrotsios, Georgios; Mountzouris, Konstantinos C; Chatzipavlidis, Iordanis; Zervakis, Georgios I

    2014-10-15

    Nine agro-industrial and forestry by-products were subjected to solid-state fermentation by Agrocybe cylindracea and Pleurotus ostreatus, and the process and end-products were comparatively evaluated. Grape marc waste plus cotton gin trash was the best performing medium for both fungi, while substrate composition had a marked effect on most cultivation parameters. Biological efficiency was positively correlated with nitrogen, lignin and ash, and negatively with hemicelluloses and carbohydrate content of substrates. Spent substrates demonstrated high reductions in hemicelluloses and cellulose in contrast to lignin; fibre fractions were correlated with nitrogen, fat and ash content of initial materials, while residual mycelial biomass was affected by mushroom productivity. Mushroom proximate analysis revealed significant variations of constituents depending on the substrate. Crude protein and fat were correlated with substrates nitrogen for both species. Alternative cultivation substrates of high potential are proposed, while spent material could be exploited as animal feed due to its upgraded properties. PMID:24837930

  8. Fermentative hydrogen production from agroindustrial lignocellulosic substrates

    Valeria, Reginatto; Regina Vasconcellos, Antnio.

    2015-06-01

    Full Text Available To achieve economically competitive biological hydrogen production, it is crucial to consider inexpensive materials such as lignocellulosic substrate residues derived from agroindustrial activities. It is possible to use (1) lignocellulosic materials without any type of pretreatment, (2) lignocellul [...] osic materials after a pretreatment step, and (3) lignocellulosic materials hydrolysates originating from a pretreatment step followed by enzymatic hydrolysis. According to the current literature data on fermentative H2 production presented in this review, thermophilic conditions produce H2 in yields approximately 75% higher than those obtained in mesophilic conditions using untreated lignocellulosic substrates. The average H2 production from pretreated material is 3.17 1.79 mmol of H2/g of substrate, which is approximately 50% higher compared with the average yield achieved using untreated materials (2.17 1.84 mmol of H2/g of substrate). Biological pretreatment affords the highest average yield 4.54 1.78 mmol of H2/g of substrate compared with the acid and basic pretreatment - average yields of 2.94 1.85 and 2.41 1.52 mmol of H2/g of substrate, respectively. The average H2 yield from hydrolysates, obtained from a pretreatment step and enzymatic hydrolysis (3.78 1.92 mmol of H2/g), was lower compared with the yield of substrates pretreated by biological methods only, demonstrating that it is important to avoid the formation of inhibitors generated by chemical pretreatments. Based on this review, exploring other microorganisms and optimizing the pretreatment and hydrolysis conditions can make the use of lignocellulosic substrates a sustainable way to produce H2.

  9. Electricity generation by microbial fuel cells fuelled with wheat straw hydrolysate

    Electricity production from microbial fuel cells fueled with hydrolysate produced by hydrothermal treatment of wheat straw can achieve both energy production and domestic wastewater purification. The hydrolysate contained mainly xylan, carboxylic acids, and phenolic compounds. Power generation and substrate utilization from the hydrolysate was compared with the ones obtained by defined synthetic substrates. The power density increased from 47 mW m−2 to 148 mW m−2 with the hydrolysate:wastewater ratio (RHW in m3 m−3) increasing from 0 to 0.06 (corresponding to 0–0.7 g dm−3 of carbohydrates). The power density with the hydrolysate was higher than the one with only xylan (120 mW m−2) and carboxylic acids as fuel. The higher power density can be caused by the presence of phenolic compounds in the hydrolysates, which could mediate electron transport. Electricity generation with the hydrolysate resulted in 95% degradation of the xylan and glucan. The study demonstrates that lignocellulosic hydrolysate can be used for co-treatment with domestic wastewater for power generation in microbial fuel cells. -- Highlights: ► Electricity production in microbial fuel cells. ► Hydrolysate from hydrothermal treated wheat straw as fuel. ► Larger electricity production than with simple compounds as fuel. ► No need for detoxification and nutrients to the hydrolysate. ► Effective (95%) microbial utilization of the polymeric carbohydrates.

  10. Pretreatments of lignocellulosic feedstock for bioethanol production

    Predojević Zlatica J.

    2010-01-01

    Full Text Available The use of renewable energy sources (biofuels, either as a component in the conventional fossil fuels, gasoline and diesel, or as a pure biofuel, contributes to energy saving and decrease of total CO2 emission. The use of bioethanol mixed with gasoline significantly decreases gasoline consumption and contributes to environment protection. One of the problems in the production of bioethanol is the availability of sugar and starch based feedstock used for its production. However, lignocellulosic feedstocks are becoming more significant in the production of bioethanol due to their availability and low cost. The aim of this study is to point out the advantages and shortcomings of pretreatment processes and hydrolyses of lignocellulosic feedstocks that precede their fermentation to bioethanol.

  11. A comparative study of the hydrolysis of gamma irradiated lignocelluloses

    E. Betiku

    2009-06-01

    Full Text Available The effect of high-dose irradiation as a pretreatment method on two common lignocellulosic materials; hardwood (Khaya senegalensis and softwood (Triplochiton scleroxylon were investigated by assessing the potential of cellulase enzyme derived from Aspergillus flavus Linn isolate NSPR 101 to hydrolyse the materials. The irradiation strongly affected the materials, causing the enzymatic hydrolysis to increase by more than 3 fold. Maximum digestibility occurred in softwood at 40kGy dosage of irradiation, while in hardwood it was at 90kGy dosage. The results also showed that, at the same dosage levels (p < 0.05, hardwood was hydrolysed significantly better compared to the softwood.

  12. Lignocellulosic bioethanol production with revalorization of low-cost agroindustrial by-products as nutritional supplements

    Kelbert, Maikon; Romaní, Aloia; Coelho, Eduardo; Pereira, Francisco B.; J. A. TEIXEIRA; Domingues, Lucília

    2015-01-01

    During the pretreatment of lignocellulosic biomass for second generation bioethanol production, fermentation inhibitors are released. To overcome this, the use of a robust industrial strain together with agro-industrial by-products as nutritional supplementation was proposed to increase ethanol productivity and yields. Two factorial experimental designs were carried out to optimize fermentation of hydrolysate from autohydrolysis of Eucalyptus globulus. The mostinfluential variable...

  13. Various pretreatments of lignocellulosics.

    Rabemanolontsoa, Harifara; Saka, Shiro

    2016-01-01

    Biomass pretreatment for depolymerizing lignocellulosics to fermentable sugars has been studied for nearly 200 years. Researches have aimed at high sugar production with minimal degradation to inhibitory compounds. Chemical, physico-chemical and biochemical conversions are the most promising technologies. This article reviews the advances and current trends in the pretreatment of lignocellulosics for a prosperous biorefinery. PMID:26316403

  14. Ethanol from lignocellulosic crops

    Wood, grasses, and most of the plant litter represent the major part of the biomass in nature and are collectively called lignocellulose. Regardless of the source, lignocellulosic materials are mainly composed of cellulose, hemicellulose, and lignin. Over 150 billion tonne of organic substances are ...

  15. Protein hydrolysates in sports nutrition

    Manninen Anssi H

    2009-09-01

    Full Text Available Abstract It has been suggested that protein hydrolysates providing mainly di- and tripeptides are superior to intact (whole proteins and free amino acids in terms of skeletal muscle protein anabolism. This review provides a critical examination of protein hydrolysate studies conducted in healthy humans with special reference to sports nutrition. The effects of protein hydrolysate ingestion on blood amino acid levels, muscle protein anabolism, body composition, exercise performance and muscle glycogen resynthesis are discussed.

  16. Bioconversion of Lignocellulose Materials

    Pothiraj, C.; P. Kanmani; P. Balaji

    2006-01-01

    One of the most economically viable processes for the bioconversion of many lignocellulosic waste is represented by white rot fungi. Phanerochaete chrysosporium is one of the important commercially cultivated fungi which exhibit varying abilities to utilize different lignocellulosic as growth substrate. Examination of the lignocellulolytic enzyme profiles of the two organisms Phanerochaete chrysosporium and Rhizopus stolonifer show this diversity to be reflected in qualitative variation in th...

  17. Biotechnological valorization potential indicator for lignocellulosic materials.

    Duarte, Luís C; Esteves, Maria P; Carvalheiro, Florbela; Gírio, Francisco M

    2007-12-01

    This report introduces the biotechnological valorization potential indicator (BVPI) concept, a metric to measure the degree of suitability of lignocellulosic materials to be used as feedstock in a biorefinery framework. This indicator groups the impact of the main factors influencing upgrade-ability, both the biological/chemical nature of the materials, and the economical, technological and geographical factors. The BVPI was applied to the identification of the most relevant opportunities and constraints pertaining to the lignocellulosic by-products from the Portuguese agro-industrial cluster. Several by-products were identified with a high valorization potential, e.g., rice husks, brewery's spent grain, tomato pomace, carob pulp, de-alcoholized grape bagasse, and extracted olive bagasse, that would greatly benefit from the further development of specific biotechnology processes, specifically concerning the upgrade of their hemicellulosic fraction. PMID:18061896

  18. Method for pretreating lignocellulosic biomass

    Kuzhiyil, Najeeb M.; Brown, Robert C.; Dalluge, Dustin Lee

    2015-08-18

    The present invention relates to a method for pretreating lignocellulosic biomass containing alkali and/or alkaline earth metal (AAEM). The method comprises providing a lignocellulosic biomass containing AAEM; determining the amount of the AAEM present in the lignocellulosic biomass; identifying, based on said determining, the amount of a mineral acid sufficient to completely convert the AAEM in the lignocellulosic biomass to thermally-stable, catalytically-inert salts; and treating the lignocellulosic biomass with the identified amount of the mineral acid, wherein the treated lignocellulosic biomass contains thermally-stable, catalytically inert AAEM salts.

  19. Ozonolysis: An advantageous pretreatment for lignocellulosic biomass revisited.

    Travaini, Rodolfo; Martín-Juárez, Judit; Lorenzo-Hernando, Ana; Bolado-Rodríguez, Silvia

    2016-01-01

    Ozonolysis, as a lignocellulosic biomass pretreatment, goes back to 80s; however, in the last years it is becoming widespread again owing to its efficiency and mild operation conditions. Ozone reacts preferably with lignin than carbohydrates, promoting biomass destructuration and delignification, and so the sugar release by enzymatic hydrolysis. The hydrolysate from pretreated biomass has being used as sugars source for second-generation fuels production, mainly ethanol, methane and hydrogen. Short-chain carboxylic acids are the main inhibitory compounds generated, being properly removed by water washing. The most common inhibitory compounds reported for other pretreatments, furfural and HMF (5-hydroxymethylfurfural), are not found in ozone-pretreated hydrolysates. Composition of pretreated biomass and ozone consumption depends on several process parameters: reactor design, moisture content, particle size, pH, reaction time, ozone/air flow and ozone concentration. Additional studies are necessary to clarify process parameters effect and to optimize the process to achieve high yields with economic feasibility. PMID:26409859

  20. Lactic Acid Production from Pretreated Hydrolysates of Corn Stover by a Newly Developed Bacillus coagulans Strain.

    Jiang, Ting; Qiao, Hui; Zheng, Zhaojuan; Chu, Qiulu; Li, Xin; Yong, Qiang; Ouyang, Jia

    2016-01-01

    An inhibitor-tolerance strain, Bacillus coagulans GKN316, was developed through atmospheric and room temperature plasma (ARTP) mutation and evolution experiment in condensed dilute-acid hydrolysate (CDH) of corn stover. The fermentabilities of other hydrolysates with B. coagulans GKN316 and the parental strain B. coagulans NL01 were assessed. When using condensed acid-catalyzed steam-exploded hydrolysate (CASEH), condensed acid-catalyzed liquid hot water hydrolysate (CALH) and condensed acid-catalyzed sulfite hydrolysate (CASH) as substrates, the concentration of lactic acid reached 45.39, 16.83, and 18.71 g/L by B. coagulans GKN316, respectively. But for B. coagulans NL01, only CASEH could be directly fermented to produce 15.47 g/L lactic acid. The individual inhibitory effect of furfural, 5-hydroxymethylfurfural (HMF), vanillin, syringaldehyde and p-hydroxybenzaldehyde (pHBal) on xylose utilization by B. coagulans GKN316 was also studied. The strain B. coagulans GKN316 could effectively convert these toxic inhibitors to the less toxic corresponding alcohols in situ. These results suggested that B. coagulans GKN316 was well suited to production of lactic acid from undetoxified lignocellulosic hydrolysates. PMID:26863012

  1. Lactic Acid Production from Pretreated Hydrolysates of Corn Stover by a Newly Developed Bacillus coagulans Strain

    Jiang, Ting; Qiao, Hui; Zheng, Zhaojuan; Chu, Qiulu; Li, Xin; Yong, Qiang; Ouyang, Jia

    2016-01-01

    An inhibitor-tolerance strain, Bacillus coagulans GKN316, was developed through atmospheric and room temperature plasma (ARTP) mutation and evolution experiment in condensed dilute-acid hydrolysate (CDH) of corn stover. The fermentabilities of other hydrolysates with B. coagulans GKN316 and the parental strain B. coagulans NL01 were assessed. When using condensed acid-catalyzed steam-exploded hydrolysate (CASEH), condensed acid-catalyzed liquid hot water hydrolysate (CALH) and condensed acid-catalyzed sulfite hydrolysate (CASH) as substrates, the concentration of lactic acid reached 45.39, 16.83, and 18.71 g/L by B. coagulans GKN316, respectively. But for B. coagulans NL01, only CASEH could be directly fermented to produce 15.47 g/L lactic acid. The individual inhibitory effect of furfural, 5-hydroxymethylfurfural (HMF), vanillin, syringaldehyde and p-hydroxybenzaldehyde (pHBal) on xylose utilization by B. coagulans GKN316 was also studied. The strain B. coagulans GKN316 could effectively convert these toxic inhibitors to the less toxic corresponding alcohols in situ. These results suggested that B. coagulans GKN316 was well suited to production of lactic acid from undetoxified lignocellulosic hydrolysates. PMID:26863012

  2. Bioconversion of lignocellulosics

    Saddler, J.N. (Forintek Canada Corp., Ottawa, ON (Canada). Eastern Forest Products Lab.); Mackie, K. (Forest Research Inst., Rotorua (NZ))

    1990-01-01

    During the 3 years from 1986 to 1988, two International Energy Agency projects, CPD 2 (Pretreatment of Lignocellulosics) and CPD 5 (Conversion of C5, Sugars to Ethanol) were combined to form Task IV -Bioconversion of Lignocellulosics. Two meetings were held, the first in Graz, Austria in 1986 and the second in Ottawa, Canada in 1988. Proceedings from each of these meetings were distributed among the participants. Round-robin tests on the chemical analysis of pretreated lignocellulosic substrates and the enzymatic hydrolysis of these substrates were carried out by the network participants. Industrial groups from member countries were invited to participate at the Ottawa meeting. Various economic models were presented to determine the techno-economic factors influencing the commercial viability of a bioconversion process. The success of the network was reflected in the attendance at the meetings, the excellent rapport of the participants and the useful information arising from the round-robin comparisons. (author).

  3. Deletion of alcohol dehydrogenase 2 gene in Pachysolen tannophilus improves ethanol production from corn stover hydrolysates

    Sen Yang

    2015-12-01

    Full Text Available Although ethanol derived from lignocellulosic biomass is a promising alternative biofuel, the conversion rate of xylose to ethanol by fermentation is not ideal due to the low efficiency of many common yeasts in utilizing xylose. Pachysolen tannophilus can convert hexose and pentose such as L-arabinose, xylose and glucose in lignocellulosic hydrolysates to ethanol simultaneously. To increase the conversion of corn stover hydrolysates to bioethanol, the effect of alcohol dehydrogenase 2 gene (adh2 deletion in P. tannophilus on bioethanol production from corn stover hydrolysates was investigated. Two adh2 deletants (heterozygote ND and homozygote MC were constructed by using the short flanking homology PCR (SFH-PCR. The ND and MC strains showed lower alcohol dehydrogenase 2 (ADH2 activity than the initial strain P-01. In the fermented pentose and hexose sugars of MC and ND, the ethanol concentrations (g/L reached 15.8 and 18.9 versus14.6 of the initial P-01, while in the corn stover hydrolysate medium, the ethanol concentrations (g/L were 9.1 for MC and 9.8 for ND versus 7.5 for the initial strain P-01. This research provides useful information for improving the conversion efficiency of hexose and pentose to bioethanol by Pachysolen tannophilus.

  4. Elucidating and alleviating impacts of lignocellulose-derived microbial inhibitors on Clostridium beijerinckii during fermentation of Miscanthus giganteus to butanol.

    Zhang, Yan; Ezeji, Thaddeus Chukwuemeka

    2014-10-01

    Fermentation of liquid hot water (LHW) pretreated Miscanthus giganteus (MG) by Clostridium beijerinckii NCIMB 8052 was investigated towards understanding the toxicity of lignocellulose-derived inhibitors to solventogenic Clostridium species vis-à-vis butanol production. While C. beijerinckii NCIMB 8052 did not grow in undiluted MG hydrolysate-based fermentation medium, supplementation of this medium with Calcium carbonate enabled the growth of C. beijerinckii NCIMB 8052 and production of butanol. Using high-performance liquid chromatography (HPLC) and spectrophotometric assays, LHW-pretreated MG was found to contain lignocellulose-derived microbial inhibitory compounds; some of which were transformed by exponentially growing C. beijerinckii to less inhibitory compounds during fermentation. Contrary to all expectations, the reduction product of furfural, furfuryl alcohol, inhibited butanol production by C. beijerinckii by more than 16 %. Collectively, these results provide new insights into why lignocellulosic biomass hydrolysates are recalcitrant to fermentation to biofuels and chemicals. PMID:25085743

  5. Ethanol production from wood hydrolysate using genetically engineered Zymomonas mobilis

    Yanase, Hideshi; Miyawaki, Hitoshi; Sakurai, Mitsugu; Kawakami, Akinori; Matsumoto, Mari; Haga, Kenji; Kojima, Motoki; Okamoto, Kenji [Tottori Univ. (Japan). Dept. of Chemistry and Biotechnology

    2012-06-15

    An ethanologenic microorganism capable of fermenting all of the sugars released from lignocellulosic biomass through a saccharification process is essential for secondary bioethanol production. We therefore genetically engineered the ethanologenic bacterium Zymomonas mobilis such that it efficiently produced bioethanol from the hydrolysate of wood biomass containing glucose, mannose, and xylose as major sugar components. This was accomplished by introducing genes encoding mannose and xylose catabolic enzymes from Escherichia coli. Integration of E. coli manA into Z. mobilis chromosomal DNA conferred the ability to co-ferment mannose and glucose, producing 91 % of the theoretical yield of ethanol within 36 h. Then, by introducing a recombinant plasmid harboring the genes encoding E. coli xylA, xylB, tal, and tktA, we broadened the range of fermentable sugar substrates for Z. mobilis to include mannose and xylose as well as glucose. The resultant strain was able to ferment a mixture of 20 g/l glucose, 20 g/l mannose, and 20 g/l xylose as major sugar components of wood hydrolysate within 72 h, producing 89.8 % of the theoretical yield. The recombinant Z. mobilis also efficiently fermented actual acid hydrolysate prepared from cellulosic feedstock containing glucose, mannose, and xylose. Moreover, a reactor packed with the strain continuously produced ethanol from acid hydrolysate of wood biomass from coniferous trees for 10 days without accumulation of residual sugars. Ethanol productivity was at 10.27 g/l h at a dilution rate of 0.25 h{sup -1}. (orig.)

  6. Industrial robust yeast isolates with great potential for fermentation of lignocellulosic biomass

    Pereira, Francisco B; Roman, Aloia; Ruiz, Hctor A.; Teixeira, J. A.; Domingues, Luclia

    2014-01-01

    The search of robust microorganisms is essential to design sustainable processes of second generation bioethanol. Yeast strains isolated from industrial environments are generally recognised to present an increased stress tolerance but no specific information is available on their tolerance towards inhibitors that come from the pretreatment of lignocellulosic materials. In this work, a strategy for the selection of different yeasts using hydrothermal hydrolysate from Eucalyptus globulus wood,...

  7. Robust yeast isolates with great potential for industrial fermentation of lignocellulose

    Pereira, Francisco B.; Romaní, Aloia; Ruíz, Héctor A.; Teixeira, J. A.; Domingues, Lucília

    2013-01-01

    Currently, it is widely acknowledged that the production of bio-ethanol from lignocellulosic hydrolysates requires that yeast strains ferment in the presence of the inhibitory compounds produced during the biomass pre-treatment. Since the discovery of the capacity of yeast to in situ detoxification of biomass-derived inhibitors, mostly 2-furfural, 5-hydroxymethylfurfural and acetic acid, significant progress has been made in understanding of yeast tolerance mechanisms avoidi...

  8. In Situ Biodiesel Production from Fast-Growing and High Oil Content Chlorella pyrenoidosa in Rice Straw Hydrolysate

    Penglin Li; Xiaoling Miao; Rongxiu Li; Jianjiang Zhong

    2011-01-01

    Rice straw hydrolysate was used as lignocellulose-based carbon source for Chlorella pyrenoidosa cultivation and the feasibility of in situ biodiesel production was investigated. 13.7?g/L sugar was obtained by enzymatic hydrolyzation of rice straw. Chlorella pyrenoidosa showed a rapid growth in the rice straw hydrolysate medium, the maximum biomass concentration of 2.83?g/L was obtained in only 48 hours. The lipid content of the cells reached as high as 56.3%. In situ transesterification was p...

  9. Evaluation of different lignocellulosic biomass pretreatments by phenotypic microarray-based metabolic analysis of fermenting yeast

    Stuart Wilkinson

    2016-03-01

    Full Text Available Advanced generation biofuel production from lignocellulosic material (LCM was investigated.  A range of different thermo-chemical pre-treatments were evaluated with different LCM. The pre-treatments included; alkaline (5% NaOH at 50°C, acid (1% H2SO4 at 121°C and autohydrolytical methods (200°C aqueous based hydrothermal and were evaluated using samples of miscanthus, wheat-straw and willow. The liberation of sugars, presence of inhibitory compounds, and the degree of enhancement of enzymatic saccharification was accessed. The suitability of the pre-treatment generated hydrolysates (as bioethanol feedstocks for Saccharomyces cerevisiae was also accessed using a phenotypic microarray that measured yeast metabolic output. The use of the alkaline pre-treatment liberated more glucose and arabinose into both the pre-treatment generated hydrolysate and also the hydrolysate produced after enzymatic hydrolysis (when compared with other pre-treatments. However, hydrolysates derived from use of alkaline pre-treatments were shown to be unsuitable as a fermentation medium due to issues with colloidal stability (high viscosity.  Use of acid or autohydrolytical pre-treatments liberated high concentrations of monosaccharides regardless of the LCM used and the hydrolysates had good fermentation performance with measurable yeast metabolic output. Acid pre-treated wheat straw hydrolysates were then used as a model system for larger scale fermentations to confirm both the results of the phenotypic microarray and its validity as an effective high-throughput screening tool.

  10. Utilization of lignocellulosic polysaccharides

    Fenske, John James

    Lignocellulosic biomass represents a vast supply of fermentable carbohydrates and functional aromatic compounds. Conversion of lignocellulosics to ethanol and other useful products would be of widespread economical and environmental benefit. Better understanding of the behavior of different lignocellulosic feedstocks in fermentation protocols as well as catalytic activities involved in lignocellulosic depolymerization will further enhance the commercial viability of biomass-to-ethanol conversion processes. The relative toxicity of the combined non-xylose components in prehydrolysates derived from three different lignocellulosic biomass feedstocks (poplar, corn stover and switchgrass, or Panicum virgatum L.) was determined using a Pichia stipits fermentation assay. The relative toxicity of the prehydrolysates, in decreasing order, was poplar-derived prehydrolysates > switchgrass-derived prehydrolysates > corn stover-derived prehydrolysates. Ethanol yields averaged 74%, 83% and 88% of control values for poplar, switchgrass and corn stover prehydrolysates, respectively. Volumetric ethanol productivities (g ethanol lsp{-1} hsp{-1}) averaged 32%, 70% and 102% of control values for poplar, switchgrass and corn stover prehydrolysates, respectively. Ethanol productivities correlated closely with acetate concentrations in the prehydrolysates; however, regression lines correlating acetate concentrations and ethanol productivities were found to be feedstock-dependent. Differences in the relative toxicity of xylose-rich prehydrolysates derived from woody and herbaceous feedstocks are likely due to the relative abundance of a variety of inhibitory compounds, e.g. acetate and aromatic compounds. Fourteen aromatic monomers present in prehydrolysates prepared from corn stover, switchgrass, and poplar were tentatively identified by comparison with published mass spectra. The concentrations of the aromatic monomers totaled 112, 141 and 247 mg(l)sp{-1} for corn stover, switchgrass and poplar prehydrolysates, respectively. The woody and herbaceous feedstocks differed in both amount and type of aromatic monomers. The cellulases of Trichoderma reesei are the most widely studied for use in the depolymerization of lignocellulosics. The Trichoderma cellobiohydrolases CBH1 and CBH2 are traditionally categorized as exo-acting cellulases. A simple individual-based model was created to explore the potential effects of native endo activity on substrate-velocity profiles. The model results indicate that an enzyme with a small amount of endo activity will show an apparent substrate inhibition as substrate levels are increased. Actual hydrolysis studies using affinity chromatography-purified CBH2 preparations from three laboratories indicate that CBH2 has native endo activity, while CBH1 does not.

  11. Combining treatments to improve the fermentation of sugarcane bagasse hydrolysates by ethanologenic Escherichia coli LY180.

    Geddes, Ryan; Shanmugam, Keelnatham T; Ingram, Lonnie O

    2015-01-01

    Inhibitory side products from dilute acid pretreatment is a major challenge for conversion of lignocellulose into ethanol. Six strategies to detoxify sugarcane hydrolysates were investigated alone, and in combinations (vacuum evaporation of volatiles, high pH treatment with ammonia, laccase, bisulfite, microaeration, and inoculum size). High pH was the most beneficial single treatment, increasing the minimum inhibitory concentration (measured by ethanol production) from 15% (control) to 70% hydrolysate. Combining treatments provided incremental improvements, consistent with different modes of action and multiple inhibitory compounds. Screening toxicity using tube cultures proved to be an excellent predictor of relative performance in pH-controlled fermenters. A combination of treatments (vacuum evaporation, laccase, high pH, bisulfite, microaeration) completely eliminated all inhibitory activity present in hydrolysate. With this combination, fermentation of hemicellulose sugars (90% hydrolysate) to ethanol was complete within 48 h, identical to the fermentation of laboratory xylose (50 g/L) in AM1 mineral salts medium (without hydrolysate). PMID:25864026

  12. Cellulase activity and dissolved organic carbon release from lignocellulose macrophyte-derived in four trophic conditions.

    Bottino, Flávia; Cunha-Santino, Marcela Bianchessi; Bianchini, Irineu

    2016-01-01

    Considering the importance of lignocellulose macrophyte-derived for the energy flux in aquatic ecosystems and the nutrient concentrations as a function of force which influences the decomposition process, this study aims to relate the enzymatic activity and lignocellulose hydrolysis in different trophic statuses. Water samples and two macrophyte species were collected from the littoral zone of a subtropical Brazilian Reservoir. A lignocellulosic matrix was obtained using aqueous extraction of dried plant material (≈40°C). Incubations for decomposition of the lignocellulosic matrix were prepared using lignocelluloses, inoculums and filtered water simulating different trophic statuses with the same N:P ratio. The particulate organic carbon and dissolved organic carbon (POC and DOC, respectively) were quantified, the cellulase enzymatic activity was measured by releasing reducing sugars and immobilized carbon was analyzed by filtration. During the cellulose degradation indicated by the cellulase activity, the dissolved organic carbon daily rate and enzyme activity increased. It was related to a fast hydrolysable fraction of cellulose that contributed to short-term carbon immobilization (ca. 10 days). After approximately 20 days, the dissolved organic carbon and enzyme activity were inversely correlated suggesting that the respiration of microorganisms was responsible for carbon mineralization. Cellulose was an important resource in low nutrient conditions (oligotrophic). However, the detritus quality played a major role in the lignocelluloses degradation (i.e., enzyme activity) and carbon release. PMID:26991278

  13. Biogas production from lignocellulosic materials

    Li SUN

    2015-01-01

    Lignocellulosic materials such as agricultural plant residues are widely available in large amounts and can be used for production of biogas without the risk of competition for arable land. However, the intricate structure of lignocellulose, a major component of the plant cell wall, limits microbial degradation and consequently results in low degradation rate and low biogas yield. The aim of this thesis was to investigate microbial communities engaged in the degradation of lignocellulose and ...

  14. Organic acids from lignocellulose: Candida lignohabitans as a new microbial cell factory.

    Bellasio, Martina; Mattanovich, Diethard; Sauer, Michael; Marx, Hans

    2015-05-01

    Biorefinery applications require microbial cell factories for the conversion of various sugars derived from lignocellulosic material into value-added chemicals. Here, the capabilities of the yeast Candida lignohabitans to utilize a range of such sugars is characterized. Substrates efficiently converted by this yeast include the pentoses xylose and arabinose. Genetic engineering of C. lignohabitans with the isolated endogenous GAP promoter and GAP terminator was successful. GFP expression was used as a proof of functionality for the isolated transcription elements. Expression of lactate dehydrogenase and cis-aconitate decarboxylase resulted in stable and reproducible production of lactic acid and itaconic acid, respectively. The desired organic acids were accumulated converting pure sugars as well as lignocellulosic hydrolysates. C. lignohabitans proved therefore to be a promising reliable microbial host for production of organic acids from lignocellulosic material. PMID:25651876

  15. Lignocellulosic ethanol production by starch-base industrial yeast under PEG detoxification

    Liu, Xiumei; Xu, Wenjuan; Mao, Liaoyuan; Zhang, Chao; Yan, Peifang; Xu, Zhanwei; Zhang, Z. Conrad

    2016-02-01

    Cellulosic ethanol production from lignocellulosic biomass offers a sustainable solution for transition from fossil based fuels to renewable alternatives. However, a few long-standing technical challenges remain to be addressed in the development of an economically viable fermentation process from lignocellulose. Such challenges include the needs to improve yeast tolerance to toxic inhibitory compounds and to achieve high fermentation efficiency with minimum detoxification steps after a simple biomass pretreatment. Here we report an in-situ detoxification strategy by PEG exo-protection of an industrial dry yeast (starch-base). The exo-protected yeast cells displayed remarkably boosted vitality with high tolerance to toxic inhibitory compounds, and with largely improved ethanol productivity from crude hydrolysate derived from a pretreated lignocellulose. The PEG chemical exo-protection makes the industrial S. cerevisiae yeast directly applicable for the production of cellulosic ethanol with substantially improved productivity and yield, without of the need to use genetically modified microorganisms.

  16. Aromatic inhibitors derived from ammonia-pretreated lignocellulose hinder bacterial ethanologenesis by activating regulatory circuits controlling inhibitor efflux and detoxification

    DonnaMBates

    2014-08-01

    Full Text Available Efficient microbial conversion of lignocellulosic hydrolysates to biofuels is a key barrier to the economically viable deployment of lignocellulosic biofuels. A chief contributor to this barrier is the impact on microbial processes and energy metabolism of lignocellulose-derived inhibitors, including phenolic carboxylates, phenolic amides (for ammonia-pretreated biomass, phenolic aldehydes, and furfurals. To understand the bacterial pathways induced by inhibitors present in ammonia-pretreated biomass hydrolysates, which are less well studied than acid-pretreated biomass hydrolysates, we developed and exploited synthetic mimics of ammonia-pretreated corn stover hydrolysate (ACSH. To determine regulatory responses to the inhibitors normally present in ACSH, we measured transcript and protein levels in an Escherichia coli ethanologen using RNA-seq and quantitative proteomics during fermentation to ethanol of synthetic hydrolysates containing or lacking the inhibitors. Our study identified four major regulators mediating these responses, the MarA/SoxS/Rob network, AaeR, FrmR, and YqhC. Induction of these regulons was correlated with a reduced rate of ethanol production, buildup of pyruvate, depletion of ATP and NAD(PH, and an inhibition of xylose conversion. The aromatic aldehyde inhibitor 5-hydroxymethylfurfural appeared to be reduced to its alcohol form by the ethanologen during fermentation whereas phenolic acid and amide inhibitors were not metabolized. Together, our findings establish that the major regulatory responses to lignocellulose-derived inhibitors are mediated by transcriptional rather than translational regulators, suggest that energy consumed for inhibitor efflux and detoxification may limit biofuel production, and identify a network of regulators for future synthetic biology efforts.

  17. The chemistry involved in the steam treatment of lignocellulosic materials

    Luiz Pereira Ramos

    2003-12-01

    Full Text Available Pretreatment of lignocellulosic materials is essential for bioconversion because of the various physical and chemical barriers that greatly inhibit their susceptibility to bioprocesses such as hydrolysis and fermentation. The aim of this article is to review some of the most important pretreatment methods developed to date to enhance the conversion of lignocellulosics. Steam explosion, which precludes the treatment of biomass with high-pressure steam under optimal conditions, is presented as the pretreatment method of choice and its mode of action on lignocellulosics is discussed. The optimal pretreatment conditions for a given plant biomass are defined as those in which the best substrate for hydrolysis is obtained with the least amount of soluble sugars lost to side reactions such as dehydration. Therefore, pretreatment optimization results from a compromise between two opposite trends because hemicellulose recovery in acid hydrolysates can only be maximized at lower pretreatment severities, whereas the development of substrate accessibility requires more drastic pretreatment conditions in which sugar losses are inevitable. To account for this heterogeneity, the importance of several process-oriented parameters is discussed in detail, such as the pretreatment temperature, residence time into the steam reactor, use of an acid catalyst, susceptibility of the pretreated biomass to bioconversion, and process design.

  18. Omega-3 fatty acid production from enzyme saccharified hemp hydrolysate using a novel marine thraustochytrid strain.

    Gupta, Adarsha; Abraham, Reinu E; Barrow, Colin J; Puri, Munish

    2015-05-01

    In this work, a newly isolated marine thraustochytrid strain, Schizochytrium sp. DT3, was used for omega-3 fatty acid production by growing on lignocellulose biomass obtained from local hemp hurd (Cannabis sativa) biomass. Prior to enzymatic hydrolysis, hemp was pretreated with sodium hydroxide to open the biomass structure for the production of sugar hydrolysate. The thraustochytrid strain was able to grow on the sugar hydrolysate and accumulated polyunsaturated fatty acids (PUFAs). At the lowest carbon concentration of 2%, the PUFAs productivity was 71% in glucose and 59% in the sugars hydrolysate, as a percentage of total fatty acids. Saturated fatty acids (SFAs) levels were highest at about 49% of TFA using 6% glucose as the carbon source. SFAs of 41% were produced using 2% of SH. This study demonstrates that SH produced from lignocellulose biomass is a potentially useful carbon source for the production of omega-3 fatty acids in thraustochytrids, as demonstrated using the new strain, Schizochytrium sp. DT3. PMID:25497057

  19. Oil production by oleaginous yeasts using the hydrolysate from pretreatment of wheat straw with dilute sulfuric acid.

    Yu, Xiaochen; Zheng, Yubin; Dorgan, Kathleen M; Chen, Shulin

    2011-05-01

    This paper explores the use of the hydrolysate from the dilute sulfuric acid pretreatment of wheat straw for microbial oil production. The resulting hydrolysate was composed of pentoses (24.3g/L) and hexoses (4.9 g/L), along with some other degradation products, such as acetic acid, furfural, and hydroxymethylfurfural (HMF). Five oleaginous yeast strains, Cryptococcus curvatus, Rhodotorula glutinis, Rhodosporidium toruloides, Lipomyces starkeyi, and Yarrowia lipolytica, were evaluated by using this hydrolysate as substrates. The results showed that all of these strains could use the detoxified hydrolysate to produce lipids while except R. toruloides non-detoxified hydrolysate could also be used for the growth of all of the selective yeast strains. C. curvatus showed the highest lipid concentrations in medium on both the detoxified (4.2g/L) and non-detoxified (5.8 g/L) hydrolysates. And the inhibitory effect studies on C. curvatus indicated HMF had insignificant impacts at a concentration of up to 3g/L while furfural inhibited cell growth and lipid content by 72.0% and 62.0% at 1g/L, respectively. Our work demonstrates that lipid production is a promising alternative to utilize hemicellulosic sugars obtained during pretreatment of lignocellulosic materials. PMID:21463940

  20. Biogas from lignocellulosic biomass

    Berglund Odhner, Peter; Schabbauer, Anna [Grontmij AB, Stockholm (Sweden); Sarvari Horvath, Ilona; Mohseni Kabir, Maryam [Hoegskolan i Boraas, Boraas (Sweden)

    2012-01-15

    Grontmij AB has cooperated with the University of Boraas to evaluate the technological and economical possibilities for biogas production from substrates containing lignocellulose, such as forest residues, straw and paper. The state of knowledge regarding biogas production from cellulosic biomass has been summarized. The research in the field has been described, especially focusing on pretreatment methods and their results on increased gas yields. An investigation concerning commercially available pretreatment methods and the cost of these technologies has been performed. An economic evaluation of biogas production from lignocellulosic materials has provided answers to questions regarding the profitability of these processes. Pretreatment with steam explosion was economically evaluated for three feedstocks - wood, straw and paper - and a combination of steam explosion and addition of NaOH for paper. The presented costs pertain to costs for the pretreatment step as it, in this study, was assumed that the pretreatment would be added to an existing plant and the lignocellulosic substrates would be part of a co-digestion process. The results of the investigation indicate that it is difficult to provide a positive net result when comparing the cost of pretreatment versus the gas yield (value) for two of the feedstocks - forest residues and straw. This is mainly due to the high cost of the raw material. For forest residues the steam pretreatment cost exceeded the gas yield by over 50 %, mainly due to the high cost of the raw material. For straw, the production cost was similar to the value of the gas. Paper showed the best economic result. The gas yield (value) for paper exceeded the pretreatment cost by 15 %, which makes it interesting to study paper further.

  1. Electricity generation from rapeseed straw hydrolysates using microbial fuel cells.

    Jablonska, Milena A; Rybarczyk, Maria K; Lieder, Marek

    2016-05-01

    Rapeseed straw is an attractive fuel material for microbial fuel cells (MFCs) due to its high content of carbohydrates (more than 60% carbohydrates). This study has demonstrated that reducing sugars can be efficiently extracted from raw rapeseed straw by combination of hydrothermal pretreatment and enzymatic hydrolysis followed by utilization as a fuel in two-chamber MFCs for electrical power generation. The most efficient method of saccharification of this lignocellulosic biomass (17%) turned out hydrothermal pretreatment followed by enzymatic hydrolysis. Electricity was produced using hydrolysate concentrations up to 150mg/dm(3). The power density reached 54mW/m(2), while CEs ranged from 60% to 10%, corresponding to the initial reducing sugar concentrations of 10-150mg/dm(3). The COD degradation rates based on charge calculation increased from 0.445gCOD/m(2)/d for the hydrolysate obtained with the microwave treatment to 0.602gCOD/m(2)/d for the most efficient combination of hydrothermal treatment followed by enzymatic hydrolysis. PMID:26930033

  2. Process Design and Economics for the Conversion of Lignocellulosic Biomass to Hydrocarbons: Dilute-Acid and Enzymatic Deconstruction of Biomass to Sugars and Catalytic Conversion of Sugars to Hydrocarbons

    Davis, R.; Tao, L.; Scarlata, C.; Tan, E. C. D.; Ross, J.; Lukas, J.; Sexton, D.

    2015-03-01

    This report describes one potential conversion process to hydrocarbon products by way of catalytic conversion of lignocellulosic-derived hydrolysate. This model leverages expertise established over time in biomass deconstruction and process integration research at NREL, while adding in new technology areas for sugar purification and catalysis. The overarching process design converts biomass to die die diesel- and naphtha-range fuels using dilute-acid pretreatment, enzymatic saccharification, purifications, and catalytic conversion focused on deoxygenating and oligomerizing biomass hydrolysates.

  3. Effect of mechanically deboned chicken meat hydrolysates on the physicochemical properties of imitation fish paste.

    Jin, Sang-Keun; Go, Gwang-Woong; Jung, Eun-Young; Lim, Hyun-Jung; Yang, Han-Sul; Park, Jae-Hong

    2014-01-01

    This study investigated on the effects of adding mechanically deboned chicken meat (MDCM) hydrolysates on the quality properties of imitation fish paste (IFP) during storage. IFP was prepared from Alaska Pollack, spent laying hens surimi and protein hydrolysates which were enzymatically extracted from MDCM. The study was designed as a 3×4 factorial design with three MDCM hydrolysate content groups (0%, 0.4%, and 0.8%) and four storage times (0, 2, 4, and 6 weeks). Addition of MDCM hydrolysates increased crude fat content but lowered water content (p<0.05). The breaking force of IFP, an indicator of gel formation, increased in treated groups compared to control (p<0.05). Angiotensin I-converting enzyme (ACE) activity was inhibited and free radical scavenging activity increased with increasing MDCM hydrolysate content (p<0.05). In conclusion, the addition of MDCM to IFP improves gel characteristics. Additionally, protein hydrolysates from MDCM serve as a potential source of ACE inhibiting peptides. PMID:25049933

  4. Treatment of rice straw hemicellulosic hydrolysates with advanced oxidative processes: a new and promising detoxification method to improve the bioconversion process

    2013-01-01

    Background The use of lignocellulosic constituents in biotechnological processes requires a selective separation of the main fractions (cellulose, hemicellulose and lignin). During diluted acid hydrolysis for hemicellulose extraction, several toxic compounds are formed by the degradation of sugars and lignin, which have ability to inhibit microbial metabolism. Thus, the use of a detoxification step represents an important aspect to be considered for the improvement of fermentation processes from hydrolysates. In this paper, we evaluated the application of Advanced Oxidative Processes (AOPs) for the detoxification of rice straw hemicellulosic hydrolysate with the goal of improving ethanol bioproduction by Pichia stipitis yeast. Aiming to reduce the toxicity of the hemicellulosic hydrolysate, different treatment conditions were analyzed. The treatments were carried out according to a Taguchi L16 orthogonal array to evaluate the influence of Fe+2, H2O2, UV, O3 and pH on the concentration of aromatic compounds and the fermentative process. Results The results showed that the AOPs were able to remove aromatic compounds (furan and phenolic compounds derived from lignin) without affecting the sugar concentration in the hydrolysate. Ozonation in alkaline medium (pH 8) in the presence of H2O2 (treatment A3) or UV radiation (treatment A5) were the most effective for hydrolysate detoxification and had a positive effect on increasing the yeast fermentability of rice straw hemicellulose hydrolysate. Under these conditions, the higher removal of total phenols (above 40%), low molecular weight phenolic compounds (above 95%) and furans (above 52%) were observed. In addition, the ethanol volumetric productivity by P. stipitis was increased in approximately twice in relation the untreated hydrolysate. Conclusion These results demonstrate that AOPs are a promising methods to reduce toxicity and improve the fermentability of lignocellulosic hydrolysates. PMID:23414668

  5. Determinants of tolerance to inhibitors in hardwood spent sulfite liquor in genome shuffled Pachysolen tannophilus strains.

    Harner, Nicole K; Bajwa, Paramjit K; Formusa, Philip A; Austin, Glen D; Habash, Marc B; Trevors, Jack T; Chan, Chi-Kin; Ho, Chi-Yip; Lee, Hung

    2015-10-01

    Genome shuffling was used to obtain Pachysolen tannophilus mutants with improved tolerance to inhibitors in hardwood spent sulfite liquor (HW SSL). Genome shuffled strains (GHW301, GHW302 and GHW303) grew at higher concentrations of HW SSL (80 % v/v) compared to the HW SSL UV mutant (70 % v/v) and the wild-type (WT) strain (50 % v/v). In defined media containing acetic acid (0.70-0.90 % w/v), GHW301, GHW302 and GHW303 exhibited a shorter lag compared to the acetic acid UV mutant, while the WT did not grow. Genome shuffled strains produced more ethanol than the WT at higher concentrations of HW SSL and an aspen hydrolysate. To identify the genetic basis of inhibitor tolerance, whole genome sequencing was carried out on GHW301, GHW302 and GHW303 and compared to the WT strain. Sixty single nucleotide variations were identified that were common to all three genome shuffled strains. Of these, 40 were in gene sequences and 20 were within 5 bp-1 kb either up or downstream of protein encoding genes. Based on the mutated gene products, mutations were grouped into functional categories and affected a variety of cellular functions, demonstrating the complexity of inhibitor tolerance in yeast. Sequence analysis of UV mutants (UAA302 and UHW303) from which GHW301, GHW302 and GHW303 were derived, confirmed the success of our cross-mating based genome shuffling strategy. Whole-genome sequencing analysis allowed identification of potential gene targets for tolerance to inhibitors in lignocellulosic hydrolysates. PMID:26231071

  6. High solids enzymatic hydrolysis of pretreated lignocellulosic materials with a powerful stirrer concept.

    Ludwig, Daniel; Michael, Buchmann; Hirth, Thomas; Rupp, Steffen; Zibek, Susanne

    2014-02-01

    In this study, we present a powerful stirred tank reactor system that can efficiently hydrolyse lignocellulosic material at high solid content to produce hydrolysates with glucose concentration > 100 g/kg. As lignocellulosic substrates alkaline-pretreated wheat straw and organosolv-pretreated beech wood were used. The developed vertical reactor was equipped with a segmented helical stirrer, which was specially designed for high biomass hydrolysis. The stirrer was characterised according to mixing behaviour and power input. To minimise the cellulase dosage, a response surface plan was used. With the empirical relationship between glucose yield, cellulase loading and solid content, the minimal cellulase dosage was calculated to reach at least 70% yield at high glucose and high substrate concentrations within 48 h. The optimisation resulted in a minimal enzyme dosage of 30 FPU/g dry matter (DM) for the hydrolysis of wheat straw and 20 FPU/g DM for the hydrolysis of beech wood. By transferring the hydrolysis reaction from shaking flasks to the stirred tank reactor, the glucose yields could be increased. Using the developed stirred tank reactor system, alkaline-pretreated wheat straw could be converted to 110 g/kg glucose (76%) at a solid content of 20% (w/w) after 48 h. Organosolv-pretreated beech wood could be efficiently hydrolysed even at 30% (w/w) DM, giving 150 g/kg glucose (72%). PMID:24242162

  7. New tools in lignocellulosic chemistry

    Salanti,

    2012-01-01

    The PhD project is inserted within the broad field of lignocellulose chemical characterization and comprehensive utilization, as promoted by the biorefinery approach. Lignocellulose is an extremely structurated natural material made up of three main biopolymers: cellulose, hemicellulose, and lignin. Cellulose consists of linear chains of beta(1-4) linked D-glucopyranose units which, when found in cell wall, is difficult to break down into glucose because of its extensive inter- and intra-...

  8. Optimization of Two-Step Acid-Catalyzed Hydrolysis of Oil Palm Empty Fruit Bunch for High Sugar Concentration in Hydrolysate

    Dongxu Zhang; Yee Ling Ong; Zhi Li; Jin Chuan Wu

    2014-01-01

    Getting high sugar concentrations in lignocellulosic biomass hydrolysate with reasonable yields of sugars is commercially attractive but very challenging. Two-step acid-catalyzed hydrolysis of oil palm empty fruit bunch (EFB) was conducted to get high sugar concentrations in the hydrolysate. The biphasic kinetic model was used to guide the optimization of the first step dilute acid-catalyzed hydrolysis of EFB. A total sugar concentration of 83.0 g/L with a xylose concentration of 69.5 g/L and...

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

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

    2016-04-01

    Aspergillus carbonarius exhibits excellent abilities to utilize a wide range of carbon sources and to produce various organic acids. In this study, wheat straw hydrolysate containing high concentrations of glucose and xylose was used for organic acid production by A. carbonarius. The results indicated that A. carbonarius efficiently co-consumed glucose and xylose and produced various types of organic acids in hydrolysate adjusted to pH 7. The inhibitor tolerance of A. carbonarius to the hydrolysate at different pH values was investigated and compared using spores and recycled mycelia. This comparison showed a slight difference in the inhibitor tolerance of the spores and the recycled mycelia based on their growth patterns. Moreover, the wild-type and a glucose oxidase deficient (Δgox) mutant were compared for their abilities to produce organic acids using the hydrolysate and a defined medium. The two strains showed a different pattern of organic acid production in the hydrolysate where the Δgox mutant produced more oxalic acid but less citric acid than the wild-type, which was different from the results obtained in the defined medium This study demonstrates the feasibility of using lignocellulosic biomass for the organic acid production by A. carbonarius. PMID:26925619

  10. BIOCONVERSION OF HEMICELLULOSE HYDROLYSATE OF SWEET SORGHUM BAGASSE TO ETHANOL BY USING PICHIA STIPITIS NCIM 3497 AND DEBARYOMYCES HANSENII SP.

    Jiby Kudakasseril Kurian

    2010-09-01

    Full Text Available Production of ethanol from concentrated D-xylose solutions and hemicellulose hydrolysate of sweet sorghum bagasse was achieved by using Pichia stipitis NCIM 3497 and an isolated yeast Debaryomyces hansenii sp. These yeasts were capable of producing ethanol from solutions containing 800 g/L D-xylose, and the optimum sugar concentration was found to be 150 g/L at pH 4, 30oC, with a production time of 72 hours. These yeasts were capable of utilizing multiple sugars. Hemicellulose hydrolysates of sweet sorghum bagasse were obtained by dilute acid hydrolysis and autohydrolysis including steam explosion treatment. The hydrolysate was treated by an over-liming process for detoxification and pH adjustment. Ethanol yield from hemicellulose hydrolysate was found to be higher than that of synthetic medium containing D-xylose. These yeasts can be used in production of ethanol from concentrated hemicellulose hydrolysates containing high pentose sugars obtained while treating lignocellulosic biomass at high substrate concentrations.

  11. Thermotolerant Yeasts for Bioethanol Production Using Lignocellulosic Substrates

    Pasha, Chand; Rao, L. Venkateswar

    No other sustainable option for production of transportation fuels can match ethanol made from lignocellulosic biomass with respect to its dramatic environmental, economic, strategic and infrastructure advantages. Substantial progress has been made in advancing biomass ethanol (bioethanol) production technology to the point that it now has commercial potential, and several firms are engaged in the demanding task of introducing first-of-a-kind technology into the marketplace to make bioethanol a reality in existing fuel-blending markets. In order to lower pollution India has a long-term goal to use biofuels (bioethanol and biodiesel). Ethanol may be used either in pure form, or as a blend in petrol in different proportions. Since the cost of raw materials, which can account up to 50 % of the total production cost, is one of the most significant factors affecting the economy of alcohol, nowadays efforts are more concentrated on using cheap and abundant raw materials. Several forms of biomass resources exist (starch or sugar crops, weeds, oil plants, agricultural, forestry and municipal wastes) but of all biomass cellulosic resources represent the most abundant global source. The lignocellulosic materials include agricultural residues, municipal solid wastes (MSW), pulp mill refuse, switchgrass and lawn, garden wastes. Lignocellulosic materials contain two types of polysaccharides, cellulose and hemicellulose, bound together by a third component lignin. The principal elements of the lignocellulosic research include: i) evaluation and characterization of the waste feedstock; ii) pretreatment including initial clean up or dewatering of the feedstock; and iii) development of effective direct conversion bioprocessing to generate ethanol as an end product. Pre-treatment of lignocellulosic materials is a step in which some of the hemicellulose dissolves in water, either as monomeric sugars or as oligomers and polymers. The cellulose cannot be enzymatically hydrolyzed to glucose without a physical and chemical pre-treatment. The pre-treatment processes normally applied on the different substrates are acidic hydrolysis, steam explosion and wet oxidation. A problem for most pretreatment methods is the generation of compounds that are inhibitory towards the fermenting microorganisms, primarily phenols. Degradation products that could have inhibitory action in later fermentation steps are avoided during pre-treatment by wet oxidation. Followed by pre treatment, hydrolysed with enzymes known as cellulases and hemicellulases, which hydrolyse cellulose and hemicellulose respectively. The production of bioethanol requires two steps, fermentation and distillation. Practically all ethanol fermentation is still based on Saccharomyces cerevisiae . The fermentation using thermotolerant yeasts has more advantageous in that they have faster fermentation rates, avoid the cooling costs, and decrease the over all fermentation costs, so that ethanol can be made available at cheaper rates. In addition they can be used for efficient simultaneous saccharification and fermentation of cellulose by cellulases because the temperature optimum of cellulase enzymes (about 40 ° C to 45 ° C) is close to the fermentation temperature of thermotolerant yeasts. Hence selection and improvement of thermotolerant yeasts for bioconversion of lignocellulosic substrates is very useful.

  12. Thermophilic lignocellulose deconstruction.

    Blumer-Schuette, Sara E; Brown, Steven D; Sander, Kyle B; Bayer, Edward A; Kataeva, Irina; Zurawski, Jeffrey V; Conway, Jonathan M; Adams, Michael W W; Kelly, Robert M

    2014-05-01

    Thermophilic microorganisms are attractive candidates for conversion of lignocellulose to biofuels because they produce robust, effective, carbohydrate-degrading enzymes and survive under harsh bioprocessing conditions that reflect their natural biotopes. However, no naturally occurring thermophile is known that can convert plant biomass into a liquid biofuel at rates, yields and titers that meet current bioprocessing and economic targets. Meeting those targets requires either metabolically engineering solventogenic thermophiles with additional biomass-deconstruction enzymes or engineering plant biomass degraders to produce a liquid biofuel. Thermostable enzymes from microorganisms isolated from diverse environments can serve as genetic reservoirs for both efforts. Because of the sheer number of enzymes that are required to hydrolyze plant biomass to fermentable oligosaccharides, the latter strategy appears to be the preferred route and thus has received the most attention to date. Thermophilic plant biomass degraders fall into one of two categories: cellulosomal (i.e. multienzyme complexes) and noncellulosomal (i.e. 'free' enzyme systems). Plant-biomass-deconstructing thermophilic bacteria from the genera Clostridium (cellulosomal) and Caldicellulosiruptor (noncellulosomal), which have potential as metabolic engineering platforms for producing biofuels, are compared and contrasted from a systems biology perspective. PMID:24118059

  13. Lignosulfonate and elevated pH can enhance enzymatic saccharification of lignocelluloses

    Wang ZJ

    2013-01-01

    Full Text Available Abstract Background Nonspecific (nonproductive binding (adsorption of cellulase by lignin has been identified as a key barrier to reduce cellulase loading for economical sugar and biofuel production from lignocellulosic biomass. Sulfite Pretreatment to Overcome Recalcitrance of Lignocelluloses (SPORL is a relatively new process, but demonstrated robust performance for sugar and biofuel production from woody biomass especially softwoods in terms of yields and energy efficiencies. This study demonstrated the role of lignin sulfonation in enhancing enzymatic saccharification of lignocelluloses – lignosulfonate from SPORL can improve enzymatic hydrolysis of lignocelluloses, contrary to the conventional belief that lignin inhibits enzymatic hydrolysis due to nonspecific binding of cellulase. Results The study found that lignosulfonate from SPORL pretreatment and from a commercial source inhibits enzymatic hydrolysis of pure cellulosic substrates at low concentrations due to nonspecific binding of cellulase. Surprisingly, the reduction in enzymatic saccharification efficiency of a lignocellulosic substrate was fully recovered as the concentrations of these two lignosulfonates increased. We hypothesize that lignosulfonate serves as a surfactant to enhance enzymatic hydrolysis at higher concentrations and that this enhancement offsets its inhibitive effect from nonspecific binding of cellulase, when lignosulfonate is applied to lignocellulosic solid substrates. Lignosulfonate can block nonspecific binding of cellulase by bound lignin on the solid substrates, in the same manner as a nonionic surfactant, to significantly enhance enzymatic saccharification. This enhancement is linearly proportional to the amount of lignosulfonate applied which is very important to practical applications. For a SPORL-pretreated lodgepole pine solid, 90% cellulose saccharification was achieved at cellulase loading of 13 FPU/g glucan with the application of its corresponding pretreatment hydrolysate coupled with increasing hydrolysis pH to above 5.5 compared with only 51% for the control run without lignosulfonate at pH 5.0. The pH-induced lignin surface modification at pH 5.5 further reduced nonspecific binding of cellulase by lignosulfonate. Conclusions The results reported in this study suggest significant advantages for SPORL-pretreatment in terms of reducing water usage and enzyme dosage, and simplifying process integration, i.e., it should eliminate washing of SPORL solid fraction for direct simultaneous enzymatic saccharification and combined fermentation of enzymatic and pretreatment hydrolysates (SSCombF. Elevated pH 5.5 or higher, rather than the commonly believed optimal and widely practiced pH 4.8-5.0, should be used in conducting enzymatic saccharification of lignocelluloses.

  14. Industrial robust yeast isolates with great potential for fermentation of lignocellulosic biomass.

    Pereira, Francisco B; Romaní, Aloia; Ruiz, Héctor A; Teixeira, José A; Domingues, Lucília

    2014-06-01

    The search of robust microorganisms is essential to design sustainable processes of second generation bioethanol. Yeast strains isolated from industrial environments are generally recognised to present an increased stress tolerance but no specific information is available on their tolerance towards inhibitors that come from the pretreatment of lignocellulosic materials. In this work, a strategy for the selection of different yeasts using hydrothermal hydrolysate from Eucalyptus globulus wood, containing different concentrations of inhibitors, was developed. Ten Saccharomyces cerevisiae and four Kluyveromyces marxianus strains isolated from industrial environments and four laboratory background strains were evaluated. Interestingly, a correlation between final ethanol titer and percentage of furfural detoxification was observed. The results presented here highlight industrial distillery environments as a remarkable source of efficient yeast strains for lignocellulosic fermentation processes. Selected strains were able to resourcefully degrade furfural and HMF inhibitors, producing 0.8g ethanol/Lh corresponding to 94% of the theoretical yield. PMID:24704884

  15. Hemicellulase production by Aspergillus niger DSM 26641 in hydrothermal palm oil empty fruit bunch hydrolysate and transcriptome analysis.

    Ottenheim, Christoph; Verdejo, Carl; Zimmermann, Wolfgang; Wu, Jin Chuan

    2014-12-01

    Palm oil empty fruit bunches (EFB) is an abundant and cheap lignocellulose material in Southeast Asia. Its use as the sole medium for producing lignocellulose-hydrolyzing enzymes would increase its commercial value. A newly isolated Aspergillus niger DSM 26641 was investigated for its capability of producing hemicellulases in EFB hydrolysate obtained by treatment with pressurized hot water (1-20%, w/v) at 120-180°C in a 1 L Parr reactor for 10-60 min. The optimal hydrolysate for the fungal growth and endoxylanase production was obtained when 10% (w/v) of empty fruit bunch was treated at 120°C or 150°C for 10 min, giving an endoxylanase activity of 24.5 mU ml(-1) on RBB-Xylan and a saccharification activity of 5 U ml(-1) on xylan (DNS assay). When the hydrolysates were produced at higher temperatures, longer treatment times or higher biomass contents, only less than 20% of the above maximal endoxylanase activity was detected, possibly due to the higher carbohydrate concentrations in the medium. Transcriptome analysis showed that 3 endoxylanases (expression levels 59-100%, the highest level was set as 100%), 2 β-xylosidases (4%), 4 side chain-cleaving arabinofuranosidases (1-95%), 1 acetyl xylan esterase (9%) and 2 ferulic acid esterases (0.3-9%) were produced together. PMID:24958131

  16. Cell surface engineering of Saccharomyces cerevisiae combined with membrane separation technology for xylitol production from rice straw hydrolysate.

    Guirimand, Gregory; Sasaki, Kengo; Inokuma, Kentaro; Bamba, Takahiro; Hasunuma, Tomohisa; Kondo, Akihiko

    2016-04-01

    Xylitol, a value-added polyol deriving from D-xylose, is widely used in both the food and pharmaceutical industries. Despite extensive studies aiming to streamline the production of xylitol, the manufacturing cost of this product remains high while demand is constantly growing worldwide. Biotechnological production of xylitol from lignocellulosic waste may constitute an advantageous and sustainable option to address this issue. However, to date, there have been few reports of biomass conversion to xylitol. In the present study, xylitol was directly produced from rice straw hydrolysate using a recombinant Saccharomyces cerevisiae YPH499 strain expressing cytosolic xylose reductase (XR), along with β-glucosidase (BGL), xylosidase (XYL), and xylanase (XYN) enzymes (co-)displayed on the cell surface; xylitol production by this strain did not require addition of any commercial enzymes. All of these enzymes contributed to the consolidated bioprocessing (CBP) of the lignocellulosic hydrolysate to xylitol to produce 5.8 g/L xylitol with 79.5 % of theoretical yield from xylose contained in the biomass. Furthermore, nanofiltration of the rice straw hydrolysate provided removal of fermentation inhibitors while simultaneously increasing sugar concentrations, facilitating high concentration xylitol production (37.9 g/L) in the CBP. This study is the first report (to our knowledge) of the combination of cell surface engineering approach and membrane separation technology for xylitol production, which could be extended to further industrial applications. PMID:26631184

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

    Keikhosro Karimi

    2008-09-01

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

  18. Trends and challenges in the microbial production of lignocellulosic bioalcohol fuels

    Weber, Christian; Farwick, Alexander; Benisch, Feline; Brat, Dawid; Dietz, Heiko; Subtil, Thorsten; Boles, Eckhard [Frankfurt Univ., Frankfurt am Main (Germany). Inst. of Molecular Biosciences

    2010-07-15

    Bioalcohols produced by microorganisms from renewable materials are promising substitutes for traditional fuels derived from fossil sources. For several years already ethanol is produced in large amounts from feedstocks such as cereals or sugar cane and used as a blend for gasoline or even as a pure biofuel. However, alcohols with longer carbon chains like butanol have even more suitable properties and would better fit with the current fuel distribution infrastructure. Moreover, ethical concerns contradict the use of food and feed products as a biofuel source. Lignocellulosic biomass, especially when considered as a waste material offers an attractive alternative. However, the recalcitrance of these materials and the inability of microorganisms to efficiently ferment lignocellulosic hydrolysates still prevent the production of bioalcohols from these plentiful sources. Obviously, no known organism exist which combines all the properties necessary to be a sustainable bioalcohol producer. Therefore, breeding technologies, genetic engineering and the search for undiscovered species are promising means to provide a microorganism exhibiting high alcohol productivities and yields, converting all lignocellulosic sugars or are even able to use carbon dioxide or monoxide, and thereby being highly resistant to inhibitors and fermentation products, and easy to cultivate in huge bioreactors. In this review, we compare the properties of various microorganisms, bacteria and yeasts, as well as current research efforts to develop a reliable lignocellulosic bioalcohol producing organism. (orig.)

  19. Sunflower protein hydrolysates reduce cholesterol micellar solubility.

    Megías, Cristina; Pedroche, Justo; Del Mar Yust, María; Alaiz, Manuel; Girón-Calle, Julio; Millán, Francisco; Vioque, Javier

    2009-06-01

    Plant protein hydrolysates are a source of bioactive peptides. There are peptides that decrease the micellar cholesterol solubility from bile acids and therefore may reduce in vivo cholesterol absorption. The presence of these peptides in sunflower protein hydrolysates has been studied. Sunflower protein hydrolysates produced with alcalase plus flavourzyme or with pepsin plus pancreatin inhibited in some degree the cholesterol incorporation to micelles. Protein hydrolysates generated after 30 min of hydrolysis with alcalase, and after 30 min of hydrolysis with pepsin, were the inhibitoriest of the cholesterol incorporation to micelles. The average amino acid hydrophobicity of inhibitory peptides in cholesterol micelles was higher than the observed in the corresponding protein hydrolysates. This high hydrophobicity probably favours their inclusion in the lipid micelles. In vivo, this inhibition may translate in a decrease of cholesterol absorption. Reported results show that a combination of different characteristics such as peptide size or hydrophobicity may be responsible of the inhibitory activity of generated peptides. PMID:19205886

  20. Sugars metabolism and ethanol production by different yeast strains from coffee industry wastes hydrolysates

    Mussatto, Solange I.; Machado, Ercília M. S.; Carneiro, Lívia M.; J. A. TEIXEIRA

    2012-01-01

    Significant amounts of wastes are generated by the coffee industry, among of which, coffee silverskin (CS) and spent coffee grounds (SCG) are the most abundantly generated during the beans roasting and instant coffee preparation, respectively. This study evaluated the sugars metabolism and production of ethanol by three different yeast strains (Saccharomyces cerevisiae, Pichia stipitis and Kluyveromyces fragilis) when cultivated in sugar rich hydrolysates produced by acid hydrolysis of CS and...

  1. Efficient hydrogen production from the lignocellulosic energy crop Miscanthus by the extreme thermophilic bacteria Caldicellulosiruptor saccharolyticus and Thermotoga neapolitana

    de Vrije Truus

    2009-06-01

    Full Text Available Abstract Background The production of hydrogen from biomass by fermentation is one of the routes that can contribute to a future sustainable hydrogen economy. Lignocellulosic biomass is an attractive feedstock because of its abundance, low production costs and high polysaccharide content. Results Batch cultures of Caldicellulosiruptor saccharolyticus and Thermotoga neapolitana produced hydrogen, carbon dioxide and acetic acid as the main products from soluble saccharides in Miscanthus hydrolysate. The presence of fermentation inhibitors, such as furfural and 5-hydroxylmethyl furfural, in this lignocellulosic hydrolysate was avoided by the mild alkaline-pretreatment conditions at a low temperature of 75°C. Both microorganisms simultaneously and completely utilized all pentoses, hexoses and oligomeric saccharides up to a total concentration of 17 g l-1 in pH-controlled batch cultures. T. neapolitana showed a preference for glucose over xylose, which are the main sugars in the hydrolysate. Hydrogen yields of 2.9 to 3.4 mol H2 per mol of hexose, corresponding to 74 to 85% of the theoretical yield, were obtained in these batch fermentations. The yields were higher with cultures of C. saccharolyticus compared to T. neapolitana. In contrast, the rate of substrate consumption and hydrogen production was higher with T. neapolitana. At substrate concentrations exceeding 30 g l-1, sugar consumption was incomplete, and lower hydrogen yields of 2.0 to 2.4 mol per mol of consumed hexose were obtained. Conclusion Efficient hydrogen production in combination with simultaneous and complete utilization of all saccharides has been obtained during the growth of thermophilic bacteria on hydrolysate of the lignocellulosic feedstock Miscanthus. The use of thermophilic bacteria will therefore significantly contribute to the energy efficiency of a bioprocess for hydrogen production from biomass.

  2. Sequential hydrolysis of waste newspaper and bioethanol production from the hydrolysate.

    Wu, Fang-Chen; Huang, Shu-Sing; Shih, Ing-Lung

    2014-09-01

    A practical process was developed for production of a high quality hydrolysate of waste newspaper that ensured its complete fermentability to bioethanol. After pretreatment with 0.1N NaOH for 12h and sequential acid and enzyme hydrolysis, 10.1g/L of glucose (50.5%), 1.38 g/L of mannose (6.9%) and 0.28 g/L of galactose (1.4%), a total of 11.76 g/L of fermentable sugars was obtained, which accounts for 88.7% of saccharification efficiency. The Saccharomyces cerevisiae BCRC20271 showed excellent co-fermentability of glucose, mannose and galactose in hydrolysate of waste newspaper. After cultivation of the hydrolysate at 24°C in static culture for 48 h, the final ethanol concentration of 5.72 g/L (96% conversion efficiency) was produced. Overall, 1000 kg of waste newspaper will produce 286 kg (362 L) of ethanol by the process developed, which reveals that waste newspaper has higher potential than many other lignocellulosic and seaweed feedstocks for bioethanol production. PMID:24980028

  3. SO{sub 2}-ethanol-water (SEW) fractionation of lignocellulosics

    Iakovlev, M.

    2011-10-15

    This study deals with SO{sub 2}-ethanol-water (SEW) fractionation as a potential method for a Lignocellulosic Biorefinery to achieve high yield separation of the three important components of biomass; cellulose, hemicelluloses and lignin. Representatives of all principal biomass species were successfully treated by SEW fractionation at similar rates. The kinetics of delignification, polysaccharides removal and cellulose hydrolysis at different temperatures and SO{sub 2} concentrations are described and interpreted from the viewpoint of acid-catalysed degradation of the biomass polymers. The fractionation pattern is compared to that of commercial acid sulfite cooking. The kinetics of delignification, hemicelluloses removal and cellulose hydrolysis during SEW fractionation each follow a two phase behaviour. The delignification is first order in lignin and SO{sub 2}. The observed lignin sulfonation and delignification patterns can be explained using Haegglund's consecutive fast sulfonation-slow hydrolysis scheme. During the initial phase of fractionation, the hemicelluloses removal and cellulose hydrolysis rates are related to the delignification rate, while in the following bulk phase the former two processes proceed independently from the latter. It is proposed that during the initial phase the hemicelluloses are removed together with lignin in the form of lignocarbohydrate complexes, while cellulose is protected by lignin from hydrolytic attack leading to a lower hydrolysis rate. Most hemicellulose side units as well as acetyl groups are cleaved during the first phase, while the glucomannan and xylan backbone polymers are removed at a considerably lower rate in the second (bulk) phase following first order kinetics in the residual polysaccharides. The observed polysaccharides dissolution behaviour can be interpreted in terms of low glucomannan stabilisation by crystallisation on cellulose at the applied conditions. Minimal cellulose dissolution occurs during fractionation, but the cellulose degree of polymerisation decreases by hydrolysis following zero-order kinetics. The products include cellulosic fibres and a spent liquor containing lignin and hydrolysed hemicellulose sugars, the latter present up to 50% in monomeric form. The investigated overall and carbohydrate material balances show no carbohydrate losses as further supported by very low amounts of formed oxidation and dehydration products. The properties of the fibre products are evaluated and their potential applications are discussed. The amount of sulfur bound to lignin is 2-3 times lower than that in acid sulfite cooking, and accounts for less than 1.1% on wood. The rest of SO{sub 2} (95-97%) can be fully recovered by distillation. (orig.)

  4. Food engineering residues: amino acid composition of hydrolysates and application for the decontamination of metal polluted soils

    Fischer, K. (GSF-Forschungszentrum, Inst. fuer Oekologische Chemie, Oberschleissheim (Germany) TU Muenchen, Lehrstuhl fuer Oekologische Chemie, Freising-Weihenstephan (Germany)); Riemschneider, P. (GSF-Forschungszentrum, Inst. fuer Oekologische Chemie, Oberschleissheim (Germany)); Bieniek, D. (GSF-Forschungszentrum, Inst. fuer Oekologische Chemie, Oberschleissheim (Germany)); Kettrup, A. (GSF-Forschungszentrum, Inst. fuer Oekologische Chemie, Oberschleissheim (Germany) TU Muenchen, Lehrstuhl fuer Oekologische Chemie, Freising-Weihenstephan (Germany))

    1994-11-01

    Several residues of the brewing industry and slaughtering offals were investigated in order to evaluate their potential as raw materials for the hydrolytic preparation of amino acid containing solutions, applicable as extractants in amelioration processes for metal polluted soils. The residues were hydrolysed with 6 mol/L hydrochloric acid and the hydrolysates were analysed for their total nitrogen, TOC, amino acid and heavy metal contents. Then, the leaching capacities of the hydrolysates were examined in a series of batch tests with a contaminated soil. High amino acid yields in relation to the weight of the air-dried raw materials were achieved with blood meal (72.5%) and poultry feather meal (56.6%). The portion of the detected amino acids of the total organic carbon content of the hydrolysates ranged from 38.9% (brewer's spent grain) to 93.6% (blood meal). In extraction tests with hydrolysates adjusted to a total amino acid concentration of 60 mmol/L and to a pH value of 7.0, maximum extraction yields of 50.3% for copper (soil content 279 mg kg[sup -1]) and 38.7% for nickel (soil content 54 mg kg[sup -1]) were reached. An increase of the hydrolysate concentration and of the pH of an amino acid mixture resulted in higher solubilisation of the metals. (orig.)

  5. Actinopyga lecanora Hydrolysates as Natural Antibacterial Agents

    Raheleh Ghanbari

    2012-12-01

    Full Text Available Actinopyga lecanora, a type of sea cucumber commonly known as stone fish with relatively high protein content, was explored as raw material for bioactive peptides production. Six proteolytic enzymes, namely alcalase, papain, pepsin, trypsin, bromelain and flavourzyme were used to hydrolyze A. lecanora at different times and their respective degrees of hydrolysis (DH were calculated. Subsequently, antibacterial activity of the A. lecanora hydrolysates, against some common pathogenic Gram positive bacteria (Bacillus subtilis and Staphylococcus aureus and Gram negative bacteria (Escherichia coli, Pseudomonas aeruginosa, and Pseudomonas sp. were evaluated. Papain hydrolysis showed the highest DH value (89.44%, followed by alcalase hydrolysis (83.35%. Bromelain hydrolysate after one and seven hours of hydrolysis exhibited the highest antibacterial activities against Pseudomonas sp., P. aeruginosa and E. coli at 51.85%, 30.07% and 30.45%, respectively compared to the other hydrolysates. Protein hydrolysate generated by papain after 8 h hydrolysis showed maximum antibacterial activity against S. aureus at 20.19%. The potent hydrolysates were further fractionated using RP-HPLC and antibacterial activity of the collected fractions from each hydrolysate were evaluated, wherein among them only three fractions from the bromelain hydrolysates exhibited inhibitory activities against Pseudomonas sp., P. aeruginosa and E. coli at 24%, 25.5% and 27.1%, respectively and one fraction of papain hydrolysate showed antibacterial activity of 33.1% against S. aureus. The evaluation of the relationship between DH and antibacterial activities of papain and bromelain hydrolysates revealed a meaningful correlation of four and six order functions.

  6. Co-fermentation of acetate and sugars facilitating microbial lipid production on acetate-rich biomass hydrolysates.

    Gong, Zhiwei; Zhou, Wenting; Shen, Hongwei; Yang, Zhonghua; Wang, Guanghui; Zuo, Zhenyu; Hou, Yali; Zhao, Zongbao K

    2016-05-01

    The process of lignocellulosic biomass routinely produces a stream that contains sugars plus various amounts of acetic acid. As acetate is known to inhibit the culture of microorganisms including oleaginous yeasts, little attention has been paid to explore lipid production on mixtures of acetate and sugars. Here we demonstrated that the yeast Cryptococcus curvatus can effectively co-ferment acetate and sugars for lipid production. When mixtures of acetate and glucose were applied, C. curvatus consumed both substrates simultaneously. Similar phenomena were also observed for acetate and xylose mixtures, as well as acetate-rich corn stover hydrolysates. More interestingly, the replacement of sugar with equal amount of acetate as carbon source afforded higher lipid titre and lipid content. The lipid products had fatty acid compositional profiles similar to those of cocoa butter, suggesting their potential for high value-added fats and biodiesel production. This co-fermentation strategy should facilitate lipid production technology from lignocelluloses. PMID:26874438

  7. Industrial scale chromatographic separation of valuable compounds from biomass hydrolysates and side streams

    Saari, P.

    2011-06-15

    Carbohydrates are composed of a number of various monosaccharides, glucose being the most abundant. Some of the monosaccharides are valuable compounds used in the food and pharmaceutical industries. They can be separated from biomass hydrolysates e.g. by chromatographic methods. In this thesis, chromatographic separation of valuable compounds using ion exchange resins was studied on an industrial scale. Of special interest were rare monosaccharides in biomass hydrolysates. A novel chromatographic separation process was developed for fucose, starting from pre-processed spent sulfite liquor. The core of the process consists of three chromatographic separations with different types of ion exchange resins. Chromatographic separation of galactose was tested with three biomass hydrolysates; lactose, gum arabic and hemicellulose hydrolysates. It was demonstrated that also galactose can be separated from complex carbohydrate mixtures. A recovery process for arabinose from citrus pectin liquid residual and for mannose from wood pulp hydrolysate were also developed and experimentally verified. In addition to monosaccharides, chromatographic separation of glycinebetaine from vinasse was examined with a hydrogen form weak acid cation exchange resin. The separation involves untypical peak formation depending, for example, on the pH and the cation composition. The retention mechanism was found to be hydrogen bonding between glycinebetaine and the resin. In the experimental part, all four resin types - strong acid cation, strong base anion, weak acid cation and weak base anion exchange resins - were used. In addition, adsorption equilibria data of seven monosaccharides and sucrose were measured with the resins in sodium and sulfate forms because such data have been lacking. It was found out that the isotherms of all sugars were linear under industrial conditions. A systematic method for conceptual process design and sequencing of chromatographic separation steps were developed. Heuristics were drawn from the current industrial practices also for the selection of a suitable ion exchange resin for the separation of a sugar from a biomass hydrolysate. (orig.)

  8. Enhanced anti-oxidative activity and lignocellulosic ethanol production by biotin addition to medium in Pichia guilliermondii fermentation.

    Qi, Kai; Xia, Xiao-Xia; Zhong, Jian-Jiang

    2015-01-01

    Commercialization of lignocellulosic ethanol fermentation requires its high titer, but the reactive oxygen species (ROS) accumulation during the bioprocess damaged the cells and compromised this goal. To improve the cellular anti-oxidative activity during non-detoxified corncob residue hydrolysate fermentation, seed cells were prepared to possess a higher level of intracellular biotin pool (IBP), which facilitated the biosyntheses of catalase and porphyrin. As a result, the catalase activity increased by 1.3-folds compared to control while the ROS level reduced by 50%. Cell viability in high-IBP cells was 1.7-folds of control and the final ethanol titer increased from 31.2 to 41.8 g L(-1) in batch fermentation. The high-IBP cells were further used for repeated-batch fermentation in the non-detoxified lignocellulosic hydrolysate, and the highest titer and average productivity of ethanol reached 63.7 g L(-1) and 1.2 g L(-1)h(-1). The results were favorable to future industrial application of this lignocellulosic bioethanol process. PMID:25864029

  9. Applications of Protein Hydrolysates in Biotechnology

    Pasupuleti, Vijai K.; Holmes, Chris; Demain, Arnold L.

    By definition, protein hydrolysates are the products that are obtained after the hydrolysis of proteins and this can be achieved by enzymes, acid or alkali. This broad definition encompasses all the products of protein hydrolysis - peptides, amino acids and minerals present in the protein and acid/alkali used to adjust pH (Pasupuleti 2006). Protein hydrolysates contain variable side chains depending on the enzymes used. These side chains could be carboxyl, amino, imidazole, sulfhydryl, etc. and they may exert specific physiological roles in animal, microbial, insect and plant cells. This introductory chapter reviews the applications of protein hydrolysates in biotechnology. The word biotechnology is so broad and for the purpose of this book, we define it as a set of technologies such as cell culture technology, bioprocessing technology that includes fermentations, genetic engineering technology, microbiology, and so on. This chapter provides introduction and leads to other chapters on manufacturing and applications of protein hydrolysates in biotechnology.

  10. Saccharification of recalcitrant biomass and integration options for lignocellulosic sugars from Catchlight Energys sugar process (CLE Sugar

    Gao Johnway

    2013-01-01

    Full Text Available Abstract Background Woody biomass is one of the most abundant biomass feedstocks, besides agriculture residuals in the United States. The sustainable harvest residuals and thinnings alone are estimated at about 75 million tons/year. These forest residuals and thinnings could produce the equivalent of 5 billion gallons of lignocellulosic ethanol annually. Softwood biomass is the most recalcitrant biomass in pretreatment before an enzymatic hydrolysis. To utilize the most recalcitrant lignocellulosic materials, an efficient, industrially scalable and cost effective pretreatment method is needed. Results Obtaining a high yield of sugar from recalcitrant biomass generally requires a high severity of pretreatment with aggressive chemistry, followed by extensive conditioning, and large doses of enzymes. Catchlight Energys Sugar process, CLE Sugar, uses a low intensity, high throughput variation of bisulfite pulping to pretreat recalcitrant biomass, such as softwood forest residuals. By leveraging well-proven bisulfite technology and the rapid progress of enzyme suppliers, CLE Sugar can achieve a high yield of total biomass carbohydrate conversion to monomeric lignocellulosic sugars. For example, 85.8% of biomass carbohydrates are saccharified for un-debarked Loblolly pine chips (softwood, and 94.0% for debarked maple chips (hardwood. Furan compound formation was 1.29% of biomass feedstock for Loblolly pine and 1.10% for maple. At 17% solids hydrolysis of pretreated softwood, an enzyme dose of 0.075 g Sigma enzyme mixture/g dry pretreated (unwashed biomass was needed to achieve 8.1% total sugar titer in the hydrolysate and an overall prehydrolysate liquor plus enzymatic hydrolysis conversion yield of 76.6%. At a much lower enzyme dosage of 0.044 g CTec2 enzyme product/g dry (unwashed pretreated softwood, hydrolysis at 17% solids achieved 9.2% total sugar titer in the hydrolysate with an overall sugar yield of 85.0% in the combined prehydrolysate liquor and enzymatic hydrolysate. CLE Sugar has been demonstrated to be effective on hardwood and herbaceous biomass, making it truly feedstock flexible. Conclusions Different options exist for integrating lignocellulosic sugar into sugar-using operations. A sugar conversion plant may be adjacent to a CLE Sugar plant, and the CLE Sugar can be concentrated from the initial 10% sugar as needed. Concentrated sugars, however, can be shipped to remote sites such as ethanol plants or other sugar users. In such cases, options for shipping a dense form of sugars include (1 pretreated biomass with enzyme addition, (2 lignocellulosic sugar syrup, and (3 lignocellulosic sugar solid. These could provide the advantage of maximizing the use of existing assets.

  11. Molten salt destruction of base hydrolysate

    Watkins, B.E.; Kanna, R.L.; Chambers, R.D.; Upadhye, R.S.; Promeda, C.O.

    1996-10-01

    There is a great need for alternatives to open burn/open detonation of explosives and propellants from dismantled munitions. LANL has investigated the use of base hydrolysis for the demilitarization of explosives. Hydrolysates of Comp B, Octol, Tritonal, and PBXN-109 were processed in the pilot molten salt unit (in building 191). NOx and CO emissions were found to be low, except for CO from PBXN-109 processing. This report describes experimental results of the destruction of the base hydrolysates.

  12. WHEY PROTEIN HYDROLYSATES: TECHNO-FUNCTIONAL PERSPECTIVE

    Sumaira H. Khan

    2013-01-01

    The paper deals with the techno-functional perspective of whey protein hydrolysates. Molecular changes occurring during protein hydrolysis result in modified techno-functional behavior of the hydrolysates compared to the intact protein such as altered solubility, viscosity, sensory properties, and emulsion and foam properties. It plays important role as an antioxidant to help increase body immune system. Whey components have ability to improve the host antioxidant defense and lower oxidant bu...

  13. Fungal treatment of lignocellulosic biomass

    Kuijk, S.J.A., van

    2016-01-01

    Summary PhD thesis Sandra J.A. van Kuijk Carbohydrates in plant cell walls are highly fermentable and could be used as a source for ruminant nutrition or biofuel production. The presence of lignin in cell walls hampers the utilization of these carbohydrates and should thus be removed. In this thesis, the possibilities of a fungal treatment of lignocellulosic biomass are investigated. A review of the scientific literature focusing on the potential of fungal treatments to increase the utilizati...

  14. Semantic text mining support for lignocellulose research

    Meurs Marie-Jean; Murphy Caitlin; Morgenstern Ingo; Butler Greg; Powlowski Justin; Tsang Adrian; Witte Ren

    2012-01-01

    Abstract Background Biofuels produced from biomass are considered to be promising sustainable alternatives to fossil fuels. The conversion of lignocellulose into fermentable sugars for biofuels production requires the use of enzyme cocktails that can efficiently and economically hydrolyze lignocellulosic biomass. As many fungi naturally break down lignocellulose, the identification and characterization of the enzymes involved is a key challenge in the research and development of biomass-deriv...

  15. Enzyme-aided Fractionation of Brewers Spent Grains in Pilot Scale

    Forssell, P.; Treimo, J.; Eijsink, V.G.H.; Faulds, C B; Collins, S; Schols, H.A.; Hinz, S.W.A.; Myllymaki, O.; Tamminen, T.; Zoldners, J.; Viljanen, K.; Waldron, K.W.; Buchert, J

    2011-01-01

    Brewers spent grain (BSG) is an important coproduct of the brewing industry and is generally used in animal feed. Recently, there has been considerable research into the use of enzymes to convert BSG into more value-added products. In this study, the efficiency of enzymatic fractionation of freshly produced BSG was studied in pilot scale. Carbohydrateand protein-degrading enzymes were applied sequentially to produce three fractions: carbohydrate hydrolysate, protein hydrolysate, and a ...

  16. Ethanol from lignocellulose - Fermentation inhibitors, detoxification and genetic engineering of Saccharomyces cerevisiae for enhanced resistance

    Larsson, Simona

    2000-07-01

    Ethanol can be produced from lignocellulose by first hydrolysing the material to sugars, and then fermenting the hydrolysate with the yeast Saccharomyces cerevisiae. Hydrolysis using dilute sulphuric acid has advantages over other methods, however, compounds which inhibit fermentation are generated during this kind of hydrolysis. The inhibitory effect of aliphatic acids, furans, and phenolic compounds was investigated. The generation of inhibitors during hydrolysis was studied using Norway spruce as raw material. It was concluded that the decrease in the fermentability coincided with increasing harshness of the hydrolysis conditions. The decrease in fermentability was not correlated solely to the content of aliphatic acids or furan derivatives. To increase the fermentability, detoxification is often employed. Twelve detoxification methods were compared with respect to the chemical composition of the hydrolysate and the fermentability after treatment. The most efficient detoxification methods were anion-exchange at pH 10.0, overliming and enzymatic detoxification with the phenol-oxidase laccase. Detailed analyses of ion exchange revealed that anion exchange and unspecific hydrophobic interactions greatly contributed to the detoxification effect, while cation exchange did not. The comparison of detoxification methods also showed that phenolic compounds are very important fermentation inhibitors, as their selective removal with laccase had a major positive effect on the fermentability. Selected compounds; aliphatic acids, furans and phenolic compounds, were characterised with respect to their inhibitory effect on ethanolic fermentation by S. cerevisiae. When aliphatic acids or furans were compared, the inhibitory effects were found to be in the same range, but the phenolic compounds displayed widely different inhibitory effects. The possibility of genetically engineering S. cerevisiae to achieve increased inhibitor resistance was explored by heterologous expression of laccase from Trametes versicolor and by homologous overexpression of phenylacrylic acid decarboxylase. Both procedures resulted in S. cerevisiae transformants displaying increased resistance towards lignocellulose-derived aromatic compounds.

  17. Improving the bioconversion yield of carbohydrates and ethanol from lignocellulosic biomass

    Ewanick, Shannon M.

    Improving the efficiency of lignocellulosic ethanol production is of the utmost importance if cellulosic bioethanol is to be competitive with fossil fuels and first generation bioethanol from starch and sucrose. Improvements in individual processes (pretreatment, saccharification, fermentation) have been ongoing, but few researchers have considered the effect that the incoming raw biomass can have on the process. It is important to understand how biomass can be altered to provide the maximum yield of hydrolysable and fermentable sugars from whatever is available. Since the moisture content is highly variable and easily altered, the effect of drying and rewetting on bioconversion was studied on switchgrass, sugarcane bagasse and hybrid poplar. For switchgrass and sugarcane bagasse, the ethanol yield after simultaneous saccharification and fermentation was improved 18-24% by increasing the moisture content by soaking prior to pretreatment. It was also found that soaking had no effect when the samples were not catalyzed with SO2 confirming that the effect of moisture content is directly related to SO2 uptake and diffusion into the biomass. In hybrid poplar, the results were similar to herbaceous biomass for chips with less than 2% absorbed SO2. However, when the SO2 uptake was increased to 3% even the air dried chips exhibited high digestibility, indicating that increased SO2 uptake can overcome the poor diffusion in dried biomass. Alongside controlling the biomass moisture content, improving knowledge and control of the processes can also increase efficiency and product yields. By monitoring reactions continuously with accurate, robust, on-line sensors, operators can detect when reactions deviate from the norm, and when they are complete. Avoiding process upsets and contamination could be the difference between an economically viable biorefinery and one that struggles to compete. Real time, continuous Raman spectroscopy was used to continuously monitor both a synthetic glucose and a lignocellulosic hydrolysate fermentation and measure glucose and ethanol. Models developed using offline HPLC validation samples had extremely high correlation between predicted and observed values for ethanol in both fermentations (R2 = 0.98 and 0.94 for synthetic and hydrolysate, respectively) while glucose proved more difficult to detect in the hydrolysate fermentation (R2 = 0.92 and 0.51). This work showed that it is possible to monitor the ethanol and glucose in a hydrolysate with a high fluorescent background.

  18. Enhanced bioproduction of poly-3-hydroxybutyrate from wheat straw lignocellulosic hydrolysates

    Cesrio, M. Teresa; Raposo, Rodrigo S.; Almeida, M. Catarina M.D. de; Keulen, Frederik; Ferreira, Bruno S.; da Fonseca, M. Manuela R.

    2014-01-01

    "Polyhydroxyalkanoates (PHAs) are bioplastics that can replace conventional petroleum derived products in various applications. One of the major barriers for their widespread introduction in the market is the higher production costs when compared with their petrochemical counterparts. In this work, a process was successfully implemented with high productivity based on wheat straw, a cheap and readily available agricultural residue, as raw material. The strain Burkholderia sacchari DSM 17165 w...

  19. Saccharification of Lignocelluloses by Carbohydrate Active Enzymes of the White Rot Fungus Dichomitus squalens.

    Rytioja, Johanna; Hildn, Kristiina; Mkinen, Susanna; Vehmaanper, Jari; Hatakka, Annele; Mkel, Miia R

    2015-01-01

    White rot fungus Dichomitus squalens is an efficient lignocellulose degrading basidiomycete and a promising source for new plant cell wall polysaccharides depolymerizing enzymes. In this work, we focused on cellobiohydrolases (CBHs) of D. squalens. The native CBHI fraction of the fungus, consisting three isoenzymes, was purified and it maintained the activity for 60 min at 50C, and was stable in acidic pH. Due to the lack of enzyme activity assay for detecting only CBHII activity, CBHII of D. squalens was produced recombinantly in an industrially important ascomycete host, Trichoderma reesei. CBH enzymes of D. squalens showed potential in hydrolysis of complex lignocellulose substrates sugar beet pulp and wheat bran, and microcrystalline cellulose, Avicel. Recombinant CBHII (rCel6A) of D. squalens hydrolysed all the studied plant biomasses. Compared to individual activities, synergistic effect between rCel6A and native CBHI fraction of D. squalens was significant in the hydrolysis of Avicel. Furthermore, the addition of laccase to the mixture of CBHI fraction and rCel6A significantly enhanced the amount of released reducing sugars from sugar beet pulp. Especially, synergy between individual enzymes is a crucial factor in the tailor-made enzyme mixtures needed for hydrolysis of different plant biomass feedstocks. Our data supports the importance of oxidoreductases in improved enzyme cocktails for lignocellulose saccharification. PMID:26660105

  20. Modified organosolv as a fractionation process of lignocellulosic biomass for co-production of fuels and chemicals

    Huijgen, W.J.J.; Van der Laan, R.R.; Reith, J.H. [ECN Solar Energy, Petten (Netherlands)

    2008-05-15

    Modified organosolv is a process by which lignocellulosic biomass can be fractionated into its three main constituents, i.e. hemicellulose, cellulose and lignin. In the process, lignocellulosic biomass is brought into contact with an organic solvent-water mixture at elevated temperature and pressure. Thus, lignin is extracted from the biomass and hemicellulose is hydrolysed, while the solid residue (mainly cellulose) is made more accessible for enzymatic hydrolysis in the subsequent process step. The goal is to achieve full fractionation of all biomass fractions, including lignin, in a sufficient quality for production of (bio)chemicals. In this work, the effect of process conditions applied, type of organic solvent and the use of catalysts is explored.

  1. State of the Art Manufacturing of Protein Hydrolysates

    Pasupuleti, Vijai K.; Braun, Steven

    The use of protein hydrolysates in microbiological media has been in existence for several decades and the basic manufacturing process of protein hydrolysates has remained the same. However, with increasing use of protein hydrolysates in specialized applications such as animal cell culture processes, the manufacturing of protein hydrolysates has dramatically improved and is still in its infancy to uncover the specific peptide, peptides and combination of individual amino acids that produce intended effects for that application. This will change as the protein hydrolysate manufacturers and end-users exchange information and work towards the common goal of developing the best protein hydrolysates for specific applications. This chapter will review the generic manufacturing of protein hydrolysates describing individual unit operations, problems faced by manufacturers and suggestions for obtaining consistent product and guidelines for the end-users in getting regulatory support and setting up reliable specifications. Finally the chapter concludes with future trends of protein hydrolysates.

  2. Lime pretreatment of lignocellulosic biomass

    Chang, Shushien

    Lignocellulose is a valuable alternative energy source. The susceptibility of lignocellulosic biomass to enzymatic hydrolysis is constrained due to its structural features, so pretreatment is essential to enhance enzymatic digestibility. Of the chemicals used as pretreatment agents, it has been reported that alkalis improve biomass digestibility significantly. In comparison with other alkalis such as NaOH and ammonia, lime (calcium hydroxide) has many advantages; it is very inexpensive, is safe, and can be recovered by carbonating wash water. The effects of lime pretreatment were explored on switchgrass and poplar wood, representing herbaceous and woody biomass, respectively. The effects of pretreatment conditions (time, temperature, lime loading, water loading, particle size, and oxygen pressure) have been systematically studies. Lime alone enhances the digestibility of switchgrass significantly; under the recommended conditions, the 3-d total sugar (glucose + xylose) yields of lime-treated switchgrass were 7 times that of untreated sample. When treating poplar wood, lime must be combined with oxygen to achieve high digestibility; oxidative lime pretreatment increased the 3-d total sugar yield of poplar wood to 12 times that of untreated sample. In a fundamental study, to determine why lime pretreatment is effective, the effects of three structural features on enzymatic digestibility were studied: lignin content, acetyl content, and crystallinity index (CrI). Poplar wood was treated with peracetic acid, potassium hydroxide, and ball milling to produce model lignocelluloses with a broad spectrum of lignin contents, acetyl contents, and CrI, respectively. Enzymatic hydrolysis was performed on the model lignocelluloses to determine the digestibility. Correlations between lignin/carbohydrate ratio, acetyl/carbohydrate ratio, CrI and digestibility were developed. The 95% prediction intervals show that the correlations predict the 1-h and 3-d total sugar conversions of a biomass sample within a precision of 5% and 20%, respectively. The digestibility of a variety of lime-treated biomass and ball-milled alpha-cellulose was compared to the correlations determined from the model compounds. The agreement between the measured and predicted values shows that the correlations are satisfactory and the three structural features---lignin content, acetyl content, and CrI---are the major factors that determine enzymatic digestibility.

  3. Biochemical and functional characterisation of casein and whey protein hydrolysates.

    Ven, van de, P.M.

    2002-01-01

    Whey protein and sodium caseinate were hydrolysed with commercially available enzyme preparations. The resulting hydrolysates were characterised using several analytical characterisation methods and by determination of several functional properties. Subsequently, correlations between the biochemical characteristics themselves and between biochemical and functional properties were studied using multivariate regression analysis.Biochemical characteristics of hydrolysates were determined using u...

  4. Ionic liquids as a tool for lignocellulosic biomass fractionation

    Lopes, André; João, Karen; Morais, Ana Rita; Bogel-Lukasik, Ewa; Bogel-Lukasik, R.

    2013-01-01

    Lignocellulosic biomass composes a diversity of feedstock raw materials representing an abundant and renewable carbon source. In majority lignocellulose is constituted by carbohydrate macromolecules, namely cellulose and hemicellulose, and by lignin, a polyphenilpropanoid macromolecule. Between these biomacromolecules, there are several covalent and non-covalent interactions defining an intricate, complex and rigid structure of lignocellulose. The deconstruction of the lignocellulosic biomass...

  5. Identification of benzoquinones in pretreated lignocellulosic feedstocks and inhibitory effects on yeast.

    Stagge, Stefan; Cavka, Adnan; Jönsson, Leif J

    2015-12-01

    Pretreatment of lignocellulosic biomass under acidic conditions gives rise to by-products that inhibit fermenting microorganisms. An analytical procedure for identification of p-benzoquinone (BQ) and 2,6-dimethoxybenzoquinone (DMBQ) in pretreated biomass was developed, and the inhibitory effects of BQ and DMBQ on the yeast Saccharomyces cerevisiae were assessed. The benzoquinones were analyzed using ultra-high performance liquid chromatography-electrospray ionization-triple quadrupole-mass spectrometry after derivatization with 2,4-dinitrophenylhydrazine. Pretreatment liquids examined with regard to the presence of BQ and DMBQ originated from six different lignocellulosic feedstocks covering agricultural residues, hardwood, and softwood, and were produced through impregnation with sulfuric acid or sulfur dioxide at varying pretreatment temperature (165-204 °C) and residence time (6-20 min). BQ was detected in all six pretreatment liquids in concentrations ranging up to 6 mg/l, while DMBQ was detected in four pretreatment liquids in concentrations ranging up to 0.5 mg/l. The result indicates that benzoquinones are ubiquitous as by-products of acid pretreatment of lignocellulose, regardless of feedstock and pretreatment conditions. Fermentation experiments with BQ and DMBQ covered the concentration ranges 2 mg/l to 1 g/l and 20 mg/l to 1 g/l, respectively. Even the lowest BQ concentration tested (2 mg/l) was strongly inhibitory to yeast, while 20 mg/l DMBQ gave a slight negative effect on ethanol formation. This work shows that benzoquinones should be regarded as potent and widespread inhibitors in lignocellulosic hydrolysates, and that they warrant attention besides more well-studied inhibitory substances, such as aliphatic carboxylic acids, phenols, and furan aldehydes. PMID:26384342

  6. Mineral and vitamin content of beef, chicken, and turkey hydrolysates mineral and vitamin content of protein hydrolysates

    Maria Elisabeth Machado Pinto E Silva; Ive Paton; Marlene Trigo; Maria Carolina B. C. von Atzingen; Carmem S. Kira; Emiko I. Inomata; Leda C. A. Lamardo

    2008-01-01

    The purpose of this study was to assess the concentration of vitamins and minerals in meat protein hydrolysates. Calcium, phosphorus and iron were analyzed by inductively coupled-plasma atomic emission spectrophotometry; vitamin C was analyzed by the reduction of cupric ions and vitamins B1 and B2 by fluorescence. Regarding minerals, the beef hydrolysate (BH) had more iron than the turkey hydrolysate (TH) and the chicken hydrolysate (CH); TH had a little more phosphorus. BH had the largest am...

  7. Biocatalytic conversion of lignocellulose to platform chemicals.

    Jger, Gernot; Bchs, Jochen

    2012-09-01

    Naturally occurring lignocellulose can be used as a renewable resource for the sustainable production of platform chemicals that can in turn be converted to valuable fine chemicals, polymers, and fuels. The biocatalytic conversion of lignocellulose is a very promising approach due to its high selectivity, mild conditions, and low exergy loss. However, such biocatalytic processes are still seldom applied at the industrial scale since the single conversion steps (pretreatment, hydrolysis, and fermentation) may exhibit low conversion rates, low efficiencies, or high costs. The biocatalytic conversion of lignocellulose to platform chemicals is reviewed in this work. Structures and production rates of lignocellulose are described, and platform chemicals that may be produced from lignocellulose are summarized. Biocatalytic conversion of lignocellulose is distinguished from conventional non-selective approaches. All essential conversion steps used in biocatalytic approaches (pretreatment, hydrolysis, and fermentation) are reviewed in detail. Finally, potential interactions between these conversion steps are highlighted and the advantages as well as disadvantages of integrated process configurations are elucidated. In conclusion, a comprehensive understanding of the biocatalytic conversion of lignocellulose is provided in this review. PMID:22829529

  8. The NILE Project - Advances in the Conversion of Lignocellulosic Materials into Ethanol

    NILE ('New Improvements for Lignocellulosic Ethanol') was an integrated European project (2005-2010) devoted to the conversion of lignocellulosic raw materials to ethanol. The main objectives were to design novel enzymes suitable for the hydrolysis of cellulose to glucose and new yeast strains able to efficiently converting all the sugars present in lignocellulose into ethanol. The project also included testing these new developments in an integrated pilot plant and evaluating the environmental and socio-economic impacts of implementing lignocellulosic ethanol on a large scale. Two model raw materials - spruce and wheat straw - both preconditioned with similar pretreatments, were used. Several approaches were explored to improve the saccharification of these pretreated raw materials such as searching for new efficient enzymes and enzyme engineering. Various genetic engineering methods were applied to obtain stable xylose- and arabinose-fermenting Saccharomyces cerevisiae strains that tolerate the toxic compounds present in lignocellulosic hydrolysates. The pilot plant was able to treat 2 tons of dry matter per day, and hydrolysis and fermentation could be run successively or simultaneously. A global model integrating the supply chain was used to assess the performance of lignocellulosic ethanol from an economical and environmental perspective. It was found that directed evolution of a specific enzyme of the cellulolytic cocktail produced by the industrial fungus, Trichoderma reesei, and modification of the composition of this cocktail led to improvements of the enzymatic hydrolysis of pretreated raw material. These results, however, were difficult to reproduce at a large scale. A substantial increase in the ethanol conversion yield and in specific ethanol productivity was obtained through a combination of metabolic engineering of yeast strains and fermentation process development. Pilot trials confirmed the good behaviour of the yeast strains in industrial conditions as well as the suitability of lignin residues as fuels. The ethanol cost and the greenhouse gas emissions were highly dependent on the supply chain but the best performing supply chains showed environmental and economic benefits. From a global standpoint, the results showed the necessity for an optimal integration of the process to co-develop all the steps of the process and to test the improvements in a flexible pilot plant, thus allowing the comparison of various configurations and their economic and environmental impacts to be determined. (authors)

  9. Mineralization of Detrital Lignocelluloses by Salt Marsh Sediment Microflora †

    Maccubbin, A. E.; Hodson, Robert E.

    1980-01-01

    Specifically radiolabeled 14C-(cellulose)-lignocellulose and 14C-(lignin)-lignocellulose were isolated from labeled cuttings of Spartina alterniflora (cordgrass) and Pinus elliottii (slash pine). These were used to estimate the rates of mineralization to CO2 of lignocelluloses of estuarine and terrestrial origin in salt marsh estuarine sediments. The lignin moiety of pine lignocellulose was mineralized 10 to 14 times more slowly than that of Spartina lignocellulose, depending on the source of...

  10. Pork fat hydrolysed by Staphylococcus xylosus

    Sørensen, B. B.; Stahnke, Louise Heller; Zeuthen, Peter

    1993-01-01

    Staphylococcus xylosus is used as a starter culture in the production of fermented sausages. Its ability to hydrolyse pork fat was investigated. Within 15 days of incubation an interaction of bacterial growth, lipase production and lipase activity in a pork fat containing medium caused liberation...

  11. Nanotubes from Partially Hydrolysed α-Lactalbumin

    Geng, Xiaolu

    . Therefore, the aim of this project was to develop a method for obtaining a large quantity of bovine a-La with a high purity and to explore the formation and structural aspects of nanotubes and gels formed from partially hydrolysed a-La under various conditions, especially over a wide range of pH values...

  12. Can lignocellulosic hydrocarbon liquids rival lignocellulose-derived ethanol as a future transport fuel?

    Yao Ding; Shengdong Zhu; Pei Yu; Shuiming Cheng; Yuanxin Wu

    2012-01-01

    Although transport fuels are currently obtained mainly from petroleum, alternative fuels derived from lignocellulosic biomass (LB) have drawn much attention in recent years in light of the limited reserves of crude oil and the associated environmental issues. Lignocellulosic ethanol (LE) and lignocellulosic hydrocarbons (LH) are two typical representatives of the LB-derived transport fuels. This editorial systematically compares LE and LB from production to their application in transport fuel...

  13. Lignocellulose conversion for biofuel: a new pretreatment greatly improves downstream biocatalytic hydrolysis of various lignocellulosic materials

    Wi, Seung Gon; Cho, Eun Jin; Lee, Dae-Seok; Lee, Soo Jung; Lee, Young Ju; Bae, Hyeun-Jong

    2015-01-01

    Background Lignocellulosic biomass is an attractive renewable resource for future liquid transport fuel. Efficient and cost-effective production of bioethanol from lignocellulosic biomass depends on the development of a suitable pretreatment system. The aim of this study is to investigate a new pretreatment method that is highly efficient and effective for downstream biocatalytic hydrolysis of various lignocellulosic biomass materials, which can accelerate bioethanol commercialization. Result...

  14. Ethanol Production from Wet-Exploded Wheat Straw Hydrolysate by Thermophilic Anaerobic Bacterium Thermoanaerobacter BG1L1 in a Continuous Immobilized Reactor

    Georgieva, Tania I.; Mikkelsen, Marie J.; Ahring, Birgitte K.

    Thermophilic ethanol fermentation of wet-exploded wheat straw hydrolysate was investigated in a continuous immobilized reactor system. The experiments were carried out in a lab-scale fluidized bed reactor (FBR) at 70C. Undetoxified wheat straw hydrolysate was used (3-12% dry matter), corresponding to sugar mixtures of glucose and xylose ranging from 12 to 41 g/1. The organism, thermophilic anaerobic bacterium Thermoanaerobacter BG1L1, exhibited significant resistance to high levels of acetic acid (up to 10 g/1) and other metabolic inhibitors present in the hydrolysate. Although the hydrolysate was not detoxified, ethanol yield in a range of 0.39-0.42 g/g was obtained. Overall, sugar efficiency to ethanol was 68-76%. The reactor was operated continuously for approximately 143 days, and no contamination was seen without the use of any agent for preventing bacterial infections. The tested microorganism has considerable potential to be a novel candidate for lignocellulose bioconversion into ethanol. The work reported here also demonstrates that the use of FBR configuration might be a viable approach for thermophilic anaerobic ethanol fermentation.

  15. Bioconversion of brewer's spent grains to bioethanol.

    White, Jane S; Yohannan, Biju K; Walker, Graeme M

    2008-11-01

    Spent grains (SG), the residue remaining after extraction of wort, are a major by-product of brewing. This lignocelluose-rich biomass may provide a source of sugars for fuel ethanol fermentations. Dilute acid and enzyme treatments were developed to convert the hemicellulose and cellulose fractions to glucose, xylose and arabinose. Pretreatment of dried, milled grains with 0.16 N HNO(3) at 121 degrees C for 15 min was chosen as the most suitable method for solubilizing grains before enzymatic digestion with cellulase and hemicellulase preparations. Solids loading concentrations (10%, 15% and 20% w/v) were compared and reducing sugar between 40 and 48 g (100 g SG)(-1) was extracted. Hydrolysate, prepared from 20% SG, pretreated with 0.16 N HNO(3), partially neutralized to pH 5-6 and digested with enzymes for 18 h, contained 27 g L(-1) glucose, 16.7 g L(-1) xylose and 11.9 g L(-1) arabinose. Fermentation of this hydrolysate for 48 h by Pichia stipitis and Kluyveromyces marxianus resulted in 8.3 and 5.9 g L(-1) ethanol corresponding to ethanol conversion yields of 0.32 and 0.23 g ethanol (g substrate)(-1), respectively. Substrate utilization efficiency was less when compared with glucose/xylose mixtures in synthetic media, suggesting that yeast inhibitory compounds derived from SG were present in the hydrolysate. PMID:18547331

  16. Developing symbiotic consortia for lignocellulosic biofuel production

    Zuroff, Trevor R.; Curtis, Wayne R. [Pennsylvania State Univ., University Park, PA (United States). Dept. of Chemical Engineering

    2012-02-15

    The search for petroleum alternatives has motivated intense research into biological breakdown of lignocellulose to produce liquid fuels such as ethanol. Degradation of lignocellulose for biofuel production is a difficult process which is limited by, among other factors, the recalcitrance of lignocellulose and biological toxicity of the products. Consolidated bioprocessing has been suggested as an efficient and economical method of producing low value products from lignocellulose; however, it is not clear whether this would be accomplished more efficiently with a single organism or community of organisms. This review highlights examples of mixtures of microbes in the context of conceptual models for developing symbiotic consortia for biofuel production from lignocellulose. Engineering a symbiosis within consortia is a putative means of improving both process efficiency and stability relative to monoculture. Because microbes often interact and exist attached to surfaces, quorum sensing and biofilm formation are also discussed in terms of consortia development and stability. An engineered, symbiotic culture of multiple organisms may be a means of assembling a novel combination of metabolic capabilities that can efficiently produce biofuel from lignocellulose. (orig.)

  17. Screening of a microbial consortium for highly simultaneous degradation of lignocellulose and chlorophenols.

    Liang, Jiajin; Peng, Xiang; Yin, Dexing; Li, Beiyin; Wang, Dehan; Lin, Yunqin

    2015-08-01

    In this work, spent mushroom substrates were utilized for screening a microbial consortium with highly simultaneous degradation of lignocellulose and chlorophenols. The desired microbial consortium OEM1 was gained through successive cultivation for about 50 generations and its stability of composition was verified by denaturing gradient gel electrophoresis (DGGE) during screening process. It could degrade lignocellulose and chlorophenols at around 50% and 100%, respectively, within 7days. The diversity analysis and the growth characteristics of OEM1 during degradation process were investigated by PCR-DGGE combined with clone and sequence. The results indicated that OEM1 consisted of 31 strains. Proteobacteria and Bacteroidetes were the predominant bacterial groups. The dynamic change of OEM1 illustrated that consortium community structure was effected by pH and substrate alteration and tended to be stable after 6days' cultivation. Furthermore, bacteria (11 strains) and actinomycetes (2 strains) were obtained based on plate isolation and identified via 16S rDNA sequence. PMID:25974352

  18. Complex xylo-oligosaccharides identified from hydrothermally treated Eucalyptus wood and brewery's spent grain.

    Kabel, M.A.; Schols, H.A.; Voragen, A. G. J.

    2002-01-01

    Hydrolysates from two hydrothermally treated xylan-rich agrobased materials, Eucalyptus wood and brewery's spent grain were fractionated by anion-exchange chromatography and size-exclusion chromatography. Hereby, several pools were obtained and they were characterised by their sugar composition. Additionally, the oligosaccharides in the pools described were further identified by high-performance anion-exchange chromatography and mass spectrometry. The hydrothermally treated brewery's spent gr...

  19. Evaluation of the activated charcoals and adsorption conditions used in the treatment of sugarcane bagasse hydrolysate for xylitol production

    J. M. Marton

    2006-03-01

    Full Text Available Xylitol has sweetening, anticariogenic and clinical properties that have attracted the attention of the food and pharmaceutical industries. The conversion of sugars from lignocellulosic biomass into xylitol by D-xylose-fermenting yeast represents an alternative to the chemical process for producing this polyol. A good source of D-xylose is sugarcane bagasse, which can be hydrolyzed with dilute acid. However, acetic acid, which is toxic to the yeast, also appears in the hydrolysate, inhibiting microbe metabolism. Xylitol production depends on the initial D-xylose concentration, which can be increased by concentrating the hydrolysate by vacuum evaporation. However, with this procedure the amount of acetic acid is also increased, aggravating the problem of cell inhibition. Hydrolysate treatment with powdered activated charcoal is used to remove or decrease the concentration of this inhibitor, improving xylitol productivity as a consequence. Our work was an attempt to improve the fermentation of Candida guilliermondii yeast in sugarcane bagasse hydrolysate by treating the medium with seven types of commercial powdered activated charcoals (Synth, Carbon Delta A, Carbon Delta G, Carbon 117, Carbon 118L, Carbon 147 and Carvorite, each with its own unique physicochemical properties. Various adsorption conditions were established for the variables temperature, contact time, shaking, pH and charcoal concentration. The experiments were based on multivariate statistical concepts, with the application of fractional factorial design techniques to identify the variables that are important in the process. Subsequently, the levels of these variables were quantified by overlaying the level curves, which permitted the establishment of the best adsorption conditions for attaining high levels of xylitol volumetric productivity and D-xylose-to-xylitol conversion. This procedure consisted in increasing the original pH of the hydrolysate to 7.0 with CaO and reducing it to 5.5 with H3PO4. Next, the hydrolysate was treated under adsorption conditions employing CDA powdered activated charcoal (1% for 30 min at 60ºC, 100 rpm and pH 2.5. The optimized xylitol volumetric productivity (0.50 g/L h corresponded to a D-xylose-to-xylitol conversion of 0.66 g/g.

  20. ETHANOL PRODUCTION FROM SPENT SUBSTRATE OF PLEUROTUS EOUS

    Jasmine Koshy

    2013-03-01

    Full Text Available Spent substrate, the residual material of mushroom cultivation, causes disposal problems for cultivators. Currently the spent substrate of different mushrooms is used mainly for composting. Edible mushrooms of Pleurotus sp. can grow on a wide range of lignocellulosic substrates. In the present study, Pleurotus eous was grown on paddy straw and the spent substrate was used for the production of ethanol. Lignocellulosic biomass cannot be saccharified by enzymes to high yield of ethanol without pretreatment. The root cause for the recalcitrance of lignocellulosic biomass such as paddy straw is the presence of lignin and hemicelluloses on the surface of cellulose. They form a barrier and prevent cellulase from accessing the cellulose in the substrate. In the untreated paddy straw, the amount of hemicelluloses and lignin (in % dry weight were 20.30 and 20.34 respectively and the total reducing sugar was estimated to be 5.40 mg/g. Extracellular xylanase and ligninases of P. eous could reduce the amount of hemicelluloses and lignin to 16 and 11(% dry weight respectively, by 21st day of cultivation. Growth of mushroom brought a seven fold increase in the total reducing sugar yield (39.20 mg/g and six fold increase in the production of ethanol (6.48 g/L after 48hrs of fermentation, when compared to untreated paddy straw.

  1. Prebiotic xylo-oligosaccharides as high-value co-products on an integrated biorefinery approach from lignocellulosic feedstock

    Moura, Patrcia; Carvalheiro, Florbela; Esteves, M. P.; Grio, Francisco M.

    2008-01-01

    The present work proposes the production of prebiotic xylo-oligosaccharides (XOS) as high-value co-products of the Lignocellulose Feedstock Biorefinery concept, foreseeing potential applications on food, feed and nutraceutical industries. Autohydrolysis was used to selectively solubilise the hemicellulosic fraction of several xylan-rich, widely available, agricultural, agro-industrial and forestry by-products: corn cobs, brewerys spent grain and Eucalyptus wood chips. The soluble hemicellulo...

  2. Engineering L-arabinose metabolism in triacylglycerol-producing Rhodococcus opacus for lignocellulosic fuel production.

    Kurosawa, Kazuhiko; Plassmeier, Jens; Kalinowski, Jörn; Rückert, Christian; Sinskey, Anthony J

    2015-07-01

    Advanced biofuels from lignocellulosic biomass have been considered as a potential solution for the issues of energy sustainability and environmental protection. Triacylglycerols (TAGs) are potential precursors for the production of lipid-based liquid biofuels. Rhodococcus opacus PD630 can accumulate large amounts of TAGs when grown under physiological conditions of high carbon and low nitrogen. However, R. opacus PD630 does not utilize the sugar L-arabinose present in lignocellulosic hydrolysates. Here, we report the engineering of R. opacus to produce TAGs on L-arabinose. We constructed a plasmid (pASC8057) harboring araB, araD and araA genes derived from a Streptomyces bacterium, and introduced the genes into R. opacus PD630. One of the engineered strains, MITAE-348, was capable of growing on high concentrations (up to 100 g/L) of L-arabinose. MITAE-348 was grown in a defined medium containing 16 g/L L-arabinose or a mixture of 8 g/L L-arabinose and 8 g/L D-glucose. In a stationary phase occurring 3 days post-inoculation, the strain was able to completely utilize the sugar, and yielded 2.0 g/L for L-arabinose and 2.2 g/L for L-arabinose/D-glucose of TAGs, corresponding to 39.7% or 42.0%, respectively, of the cell dry weight. PMID:25936337

  3. Physicochemical and bitterness properties of enzymatic pea protein hydrolysates.

    Humiski, L M; Aluko, R E

    2007-10-01

    The effects of different proteolytic treatments on the physiochemical and bitterness properties of pea protein hydrolysates were investigated. A commercial pea protein isolate was digested using each of 5 different proteases to produce protein hydrolysates with varying properties. After 4 h of enzyme digestion, samples were clarified by centrifugation followed by desalting of the supernatant with a 1000 Da membrane; the retentates were then freeze-dried. Alcalase and Flavourzymetrade mark produced protein hydrolysates with significantly higher (P pea protein hydrolysates because of the low bitterness scores combined with a high level of angiotensin converting enzyme inhibition and moderate free radical scavenging activity. PMID:17995627

  4. Expression of fungal acetyl xylan esterase in Arabidopsis thaliana improves saccharification of stem lignocellulose.

    Pawar, Prashant Mohan-Anupama; Derba-Maceluch, Marta; Chong, Sun-Li; Gmez, Leonardo D; Miedes, Eva; Banasiak, Alicja; Ratke, Christine; Gaertner, Cyril; Mouille, Grgory; McQueen-Mason, Simon J; Molina, Antonio; Sellstedt, Anita; Tenkanen, Maija; Mellerowicz, Ewa J

    2016-01-01

    Cell wall hemicelluloses and pectins are O-acetylated at specific positions, but the significance of these substitutions is poorly understood. Using a transgenic approach, we investigated how reducing the extent of O-acetylation in xylan affects cell wall chemistry, plant performance and the recalcitrance of lignocellulose to saccharification. The Aspergillus niger acetyl xylan esterase AnAXE1 was expressed in Arabidopsis under the control of either the constitutively expressed 35S CAMV promoter or a woody-tissue-specific GT43B aspen promoter, and the protein was targeted to the apoplast by its native signal peptide, resulting in elevated acetyl esterase activity in soluble and wall-bound protein extracts and reduced xylan acetylation. No significant alterations in cell wall composition were observed in the transgenic lines, but their xylans were more easily digested by a ?-1,4-endoxylanase, and more readily extracted by hot water, acids or alkali. Enzymatic saccharification of lignocellulose after hot water and alkali pretreatments produced up to 20% more reducing sugars in several lines. Fermentation by Trametes versicolor of tissue hydrolysates from the line with a 30% reduction in acetyl content yielded ~70% more ethanol compared with wild type. Plants expressing 35S:AnAXE1 and pGT43B:AnAXE1 developed normally and showed increased resistance to the biotrophic pathogen Hyaloperonospora arabidopsidis, probably due to constitutive activation of defence pathways. However, unintended changes in xyloglucan and pectin acetylation were only observed in 35S:AnAXE1-expressing plants. This study demonstrates that postsynthetic xylan deacetylation in woody tissues is a promising strategy for optimizing lignocellulosic biomass for biofuel production. PMID:25960248

  5. 2G ethanol from the whole sugarcane lignocellulosic biomass

    Pereira, Sandra Cerqueira; Maehara, Larissa; Machado, Cristina Maria Monteiro; Farinas, Cristiane Sanchez

    2015-01-01

    Background In the sugarcane industry, large amounts of lignocellulosic residues are generated, which includes bagasse, straw, and tops. The use of the whole sugarcane lignocellulosic biomass for the production of second-generation (2G) ethanol can be a potential alternative to contribute to the economic viability of this process. Here, we conducted a systematic comparative study of the use of the lignocellulosic residues from the whole sugarcane lignocellulosic biomass (bagasse, straw, and to...

  6. The Effects of Mechanically Deboned Chicken Hydrolysates on the Characteristics of Imitation Crab Stick

    Jin, Sang-Keun; Hwang, Jin-Won; Moon, Sungsil; Choi, Yeung-Joon; Kim, Gap-Don; Jung, Eun-Young; Yang, Han-Sul

    2014-01-01

    The effects of adding mechanically deboned chicken (MDC) hydrolysates on the quality characteristics of imitation crab stick (ICS) during storage were investigated. ICS was prepared from Alaska Pollack, chicken breast surimi, and protein hydrolysates enzymatically extracted from MDC. ICS samples were divided into 4 groups: without protein hydrolysate (control), added with 0.5% protein hydrolysate (T1), added with 1.0% protein hydrolysate (T2), and added with 1.5% protein hydrolysate (T3). Res...

  7. Fructooligosaccharides and β-fructofuranosidase production by Aspergillus japonicus immobilized on lignocellulosic materials

    Solange I. Mussatto; Aguilar Gonzalez, Cristobal Noé; Rodrigues, L. R.; Teixeira, J. A.

    2009-01-01

    This work describes the fructooligosaccharides (FOS) and β-fructofuranosidase (FFase) production from sucrose (200 g/l) by Aspergillus japonicus ATCC 20236 immobilized on different lignocellulosic materials including brewer's spent grain, wheat straw, corn cobs, coffee husks, cork oak, and loofa sponge. Transfructosylating (Ut) and hydrolyzing (Uh) activities of FFase were also determined. The FOS production and FFase activity ranged from 128.35 to 138.73 g/l, and 26.83 to 44.81 U/ml, respect...

  8. Decolorization of hair dye by lignocellulosic waste materials from contaminated waters

    AbelEnriqueNavarro; KarlaAliciaOrtiz; MaríaRosarioSun Kou

    2014-01-01

    Basic yellow 57 (BY57) was chosen as a model hair dye due to its prevalence in cosmetics wastewaters. This study proposes the use of lignocellulosic materials like spent tea leaves of peppermint (PM), chai tea (CT), and chamomile (CM) as raw adsorbents for the removal of BY57 from contaminated solutions. Batch adsorption experiments were carried out at room temperature to achieve the maximum adsorption capacity. Results indicate that the highest removal is achieved at pH 6–8, with a minimum a...

  9. Laccase Application for Upgrading of Lignocellulose Fibers

    Maja Vaukner Gabrič

    2015-04-01

    Full Text Available Laccases have the ability to oxidize both phenolic and trough mediators non-phenolic lignin related compounds. When reacting on lignin, they can display both ligninolytic and polymerizing (cross-inking abilities, which makes them very useful for their application in industries based on lignocellulose material. Most of the published papers and applications of laccase and laccase-mediator systems on lignocellulose material relate to the pulp, paper and textile industry. Recent research has been done in terms of laccase assisted biografting of phenols and other compounds on wood surface and use of laccase for adhesion enhancement in fiberboard production. They can be introduced to wood technology as environmentally friendly enzymes. The paper reviews the application of laccases in industries based on lignocellulose material and discusses the future outlook and development in the above mentioned fields.

  10. Sustainable Process Design of Lignocellulose based Biofuel

    Mangnimit, Saranya; Malakul, Pomthong; Gani, Rafiqul

    the production and use of alternative and sustainable energy sources as rapidly as possible. Biofuel is a type of alternative energy that can be produced from many sources including sugar substances (such as sugarcane juice and molasses), starchy materials (such as corn and cassava), and...... lignocellulosic materials such as agricultural residual, straw and wood chips, the residual from wood industry. However, those sugar and starchy materials can be used not only to make biofuels but they are also food sources. Thus, lignocellulosic materials are interesting feed-stocls as they are inexpensive...

  11. Enzymatic conversion of lignocellulose into fermentable sugars

    Jørgensen, Henning; Kristensen, Jan Bach; Felby, Claus

    2007-01-01

    technology for pretreatment and hydrolysis has been developed to an extent that is close to a commercially viable level. It has become possible to process lignocellulose at high substrate levels and the enzyme performance has been improved. Also the cost of enzymes has been reduced. Still a number of...... technical and scientific issues within pretreatment and hydrolysis remain to be solved. However, significant improvements in yield and cost reductions are expected, thus making large-scale fermentation of lignocellulosic substrates possible. © 2007 Society of Chemical Industry and John Wiley & Sons, Ltd...

  12. Production of Ethanol from Cocoa Pod Hydrolysate

    Othman Abd Samah; Salihan Sias

    2011-01-01

    Cocoa pod (Theobroma cacao L.) hydrolysate was hydrolyzed into glucose using hydrochloric, sulphuric and nitric acids, respectively. The concentration of each acid was set at 0.25 M, 0.50 M, 0.75 M, 1.00 M and 1.25 M. They were treated under two different temperatures and time at 75˚C and 90˚C for 2 h and 4 h, respectively. The results showed that hydrolysis in 1.00 M of hydrochloric acid at 75˚C for 4 h had produced the highest glucose content of 30.7% w/v compared to all others acids treate...

  13. GENETICALLY MODIFIED LIGNOCELLULOSIC BIOMASS FOR IMPROVEMENT OF ETHANOL PRODUCTION

    Qijun Wang

    2010-02-01

    Full Text Available Production of ethanol from lignocellulosic feed-stocks is of growing interest worldwide in recent years. However, we are currently still facing significant technical challenges to make it economically feasible on an industrial scale. Genetically modified lignocellulosic biomass has provided a potential alternative to address such challenges. Some studies have shown that genetically modified lignocellulosic biomass can increase its yield, decreasing its enzymatic hydrolysis cost and altering its composition and structure for ethanol production. Moreover, the modified lignocellulosic biomass also makes it possible to simplify the ethanol production procedures from lignocellulosic feed-stocks.

  14. Novel biomixtures based on local Mediterranean lignocellulosic materials: evaluation for use in biobed systems.

    Karanasios, Evangelos; Tsiropoulos, Nikolaos G; Karpouzas, Dimitrios G; Menkissoglu-Spiroudi, Urania

    2010-08-01

    The composition of biomixtures strongly affect the efficacy of biobeds. Typically, biomixture consists of peat (or compost), straw (STR) and topsoil (1:2:1 by volume). Straw guarantees a continuous supply of nutrients and high microbial activity. However, in south Europe other lignocellulosic materials including sunflower crop residues (SFR), olive leaves, grape stalks (GS), orange peels, corn cobs (CC) and spent mushroom substrate (SMS) are also readily available at no cost. Their potential utilization in biomixtures instead of STR was tested in pesticide degradation and adsorption studies. The microbial activity in these biomixtures was also assessed. The GS-biomixture was the most efficient in pesticide degradation, while CC- and SFR-biomixtures showed comparable degrading efficacy with the STR-biomixture. The SMS-biomixture was also highly efficient in degrading the pesticide mixture with degradation rates being correlated with the proportion of SMS in the biomixture. Microbial respiration was positively correlated with the degradation rates of metalaxyl, azoxystrobin and chlorpyrifos, compared to phenoloxidase which showed no correlation. Biomixtures containing alternative lignocellulosic materials showed a higher adsorption affinity for terbuthylazine and metribuzin compared to the STR-biomixture. We provide first evidence that STR can be substituted in biomixtures by other lignocellulosic materials which are readily available in south Europe. PMID:20594578

  15. Antioxidant Activity of Protein Hydrolysates of Fish and Chicken Bones

    G.S. Centenaro

    2011-08-01

    Full Text Available Argentine croaker (Umbrina canosai and chicken (Gallus domesticus bones were hydrolyzed with different proteases (Flavourzyme, α-Chymotrypsin and Trypsin in order to obtain peptides whit antioxidant activity. The hydrolysates showed different degrees of hydrolysis and antioxidant activity. The antioxidant power of the hydrolysates was evaluated through inhibition of the peroxidation of linoleic acid, hydroxyl radical scavenging, DPPH free radical scavenging, ABTS free radical scavenging and reducing power. The hydrolysates of the fish (FF and chicken (CF bones produced with Flavourzyme had high activity of lipid peroxidation inhibition (77.3 and 61.6%, respectively and moderate DPPH free radical scavenging, ABTS scavenging and hydroxyl radical scavenging activity. The fraction <3000 Da was the main constituent of the six hydrolysates followed by the fraction <1000 Da. The results of this study suggest that protein hydrolysates of fish and chicken bones are good sources of natural antioxidants. FF showed better performance e can be used as antioxidant substance.

  16. Advances in lignocellulosic biotechnology: A brief review on lignocellulosic biomass and cellulases

    Tanzila Shahzadi; Sajid Mehmood; Muhammad Irshad; Zahid Anwar; Amber Afroz; Nadia Zeeshan; Umer Rashid; Kalsoom Sughra

    2014-01-01

    From the last few decades, there has been an increasing research interest in the value of lignocellulosic biomass. Lignoellulosic biomass is an inexpensive, renewable abundant and provides a unique natural resource for large-scale and cost-effective bio-energy collection. In addition, using lignocellulosic materials and other low-cost biomass can significantly reduce the cost of materials used for ethanol production. Therefore, in this background, the rapidly evolving t...

  17. Recent Developments in the Bioconversion of Lignocelluloses into Ethanol

    KOESNANDAR

    2008-12-01

    Full Text Available Ethanol has been commercially produced using sugars derived from sugarcane and corn. Recently, research has been focused on the development of thermotolerant and ethanol-tolerant yeast or bacteria that are able to produce ethanol efficiently, as well as the development of lignocellulosic materials as the carbon sources of fermentation. Utilization of lignocellulosic materials as fermentation substrate is promising since they are available in large amounts, renewable and relatively cheap. A lignocellulose biomass is a complex mixture of carbohydrate polymers. In order to develop an efficient process, there have been many attempts to obtain more efficient ways in the conversion of lignocelluloses to ethanol, including pretreatment, enzymatic hydrolysis of lignocelluloses and direct co-culture fermentation. This paper describes the production process of ethanol from starch-containing material, recent developments on the enzymatic bioconversion of lignocelluloses into sugars and their subsequent fermentation into ethanol and the possible recombination of microbes for the direct conversion of lignocelluloses into ethanol.

  18. Affinity purification of copper chelating peptides from chickpea protein hydrolysates.

    Megías, Cristina; Pedroche, Justo; Yust, Maria M; Girón-Calle, Julio; Alaiz, Manuel; Millan, Francisco; Vioque, Javier

    2007-05-16

    Chickpea protein hydrolysates obtained with alcalase and flavourzyme were used for purification of copper chelating peptides by affinity chromatography using copper immobilized on solid supports. The chelating activity of purified peptides was indirectly measured by the inhibition of beta-carotene oxidation in the presence of copper. Two protein hydrolysates, obtained after 10 and 100 min of hydrolysis, were the most inhibitory of beta-carotene oxidation. Purified copper chelating peptides from these protein hydrolysates contained 19.7 and 35.1% histidine, respectively, in comparison to 2.7 and 2.6% in the protein hydrolysates. Chelating peptides from hydrolysate obtained after 10 min of hydrolysis were the most antioxidative being 8.3 times more antioxidative than the hydrolysate, while chelating peptides purified from protein hydrolysate obtained after 100 min were 3.1 times more antioxidative than its hydrolysate. However, the histidine content was higher in peptides derived from the 100 min hydrolysate (19.7 against 35.1% in 10 min hydrolysate), indicating that this amino acid is not the only factor involved in the antioxidative activity, and other factors such as peptide size or amino acid sequence are also determinant. This manuscript shows that affinity chromatography is a useful procedure for purification of copper chelating peptides. This method can be extended to other metals of interest in nutrition, such as calcium, iron, or zinc. Purified chelating peptides, in addition to their antioxidative properties, may also be useful in food mineral fortification for increasing the bioavailability of these metals. PMID:17428066

  19. Brewer's spent grain as raw material for lactic acid production by Lactobacillus delbrueckii.

    Mussatto, Solange I; Fernandes, Marcela; Dragone, Giuliano; Mancilha, Ismael M; Roberto, Ins C

    2007-12-01

    Chemically pre-treated brewer's spent grain was saccharified with cellulase producing a hydrolysate with approx. 50 g glucose l(-1). This hydrolysate was used as a fermentation medium without any nutrient supplementation by Lactobacillus delbrueckii, which produced L-lactic acid (5.4 g l(-1)) at 0.73 g g(-1) glucose consumed (73% efficiency). An inoculum of 1 g dry cells l(-1) gave the best yield of the process, but the pH decrease affected the microorganism capacity to consume glucose and convert it into lactic acid. PMID:17700998

  20. Semantic text mining support for lignocellulose research

    Meurs Marie-Jean

    2012-04-01

    Full Text Available Abstract Background Biofuels produced from biomass are considered to be promising sustainable alternatives to fossil fuels. The conversion of lignocellulose into fermentable sugars for biofuels production requires the use of enzyme cocktails that can efficiently and economically hydrolyze lignocellulosic biomass. As many fungi naturally break down lignocellulose, the identification and characterization of the enzymes involved is a key challenge in the research and development of biomass-derived products and fuels. One approach to meeting this challenge is to mine the rapidly-expanding repertoire of microbial genomes for enzymes with the appropriate catalytic properties. Results Semantic technologies, including natural language processing, ontologies, semantic Web services and Web-based collaboration tools, promise to support users in handling complex data, thereby facilitating knowledge-intensive tasks. An ongoing challenge is to select the appropriate technologies and combine them in a coherent system that brings measurable improvements to the users. We present our ongoing development of a semantic infrastructure in support of genomics-based lignocellulose research. Part of this effort is the automated curation of knowledge from information on fungal enzymes that is available in the literature and genome resources. Conclusions Working closely with fungal biology researchers who manually curate the existing literature, we developed ontological natural language processing pipelines integrated in a Web-based interface to assist them in two main tasks: mining the literature for relevant knowledge, and at the same time providing rich and semantically linked information.

  1. Fermentable sugar production from lignocellulosic biomass

    Fermentable sugar production from lignocellulosic biomass has become an important research focus in the production of renewable biofuels and other bio-products. It means conversion of the carbohydrates contained in the biomass, including cellulose, hemicellose, and/or pectin into their component sug...

  2. Mineral and vitamin content of beef, chicken, and turkey hydrolysates mineral and vitamin content of protein hydrolysates

    Maria Elisabeth Machado Pinto e Silva

    2008-01-01

    Full Text Available The purpose of this study was to assess the concentration of vitamins and minerals in meat protein hydrolysates. Calcium, phosphorus and iron were analyzed by inductively coupled-plasma atomic emission spectrophotometry; vitamin C was analyzed by the reduction of cupric ions and vitamins B1 and B2 by fluorescence. Regarding minerals, the beef hydrolysate (BH had more iron than the turkey hydrolysate (TH and the chicken hydrolysate (CH; TH had a little more phosphorus. BH had the largest amount of vitamin C, and similar amounts of vitamins B1 and B2. The amount of these nutrients found in the hydrolysates suggests that it is possible to use them to enrich special dietary formulations.

  3. Combining inhibitor tolerance and D-xylose fermentation in industrial Saccharomyces cerevisiae for efficient lignocellulose-based bioethanol production

    2013-01-01

    Background In addition to efficient pentose utilization, high inhibitor tolerance is a key trait required in any organism used for economically viable industrial bioethanol production with lignocellulose biomass. Although recent work has succeeded in establishing efficient xylose fermentation in robust industrial Saccharomyces cerevisiae strains, the resulting strains still lacked sufficient inhibitor tolerance for efficient sugar fermentation in lignocellulose hydrolysates. The aim of the present work was to combine high xylose fermentation activity and high inhibitor tolerance in a single industrial yeast strain. Results We have screened 580 yeast strains for high inhibitor tolerance using undetoxified acid-pretreated spruce hydrolysate and identified a triploid industrial baker’s yeast strain as having the highest inhibitor tolerance. From this strain, a mating competent diploid segregant with even higher inhibitor tolerance was obtained. It was crossed with the recently developed D-xylose fermenting diploid industrial strain GS1.11-26, with the Ethanol Red genetic background. Screening of 819 diploid segregants from the tetraploid hybrid resulted in two strains, GSF335 and GSF767, combining high inhibitor tolerance and efficient xylose fermentation. In a parallel approach, meiotic recombination of GS1.11-26 with a haploid segregant of Ethanol Red and screening of 104 segregants resulted in a similar inhibitor tolerant diploid strain, GSE16. The three superior strains exhibited significantly improved tolerance to inhibitors in spruce hydrolysate, higher glucose consumption rates, higher aerobic growth rates and higher maximal ethanol accumulation capacity in very-high gravity fermentation, compared to GS1.11-26. In complex medium, the D-xylose utilization rate by the three superior strains ranged from 0.36 to 0.67 g/g DW/h, which was lower than that of GS1.11-26 (1.10 g/g DW/h). On the other hand, in batch fermentation of undetoxified acid-pretreated spruce hydrolysate, the three superior strains showed comparable D-xylose utilization rates as GS1.11-26, probably because of their higher inhibitor tolerance. They produced up to 23% more ethanol compared to Ethanol Red. Conclusions We have successfully constructed three superior industrial S. cerevisiae strains that combine efficient D-xylose utilization with high inhibitor tolerance. Since the background strain Ethanol Red has a proven record of successful industrial application, the three new superior strains have strong potential for direct application in industrial bioethanol production. PMID:23971950

  4. Catalytic fast pyrolysis of lignocellulosic biomass

    Liu, Changjun; Wang, Huamin; Karim, Ayman M.; Sun, Junming; Wang, Yong

    2014-11-21

    Increasing energy demand, especially in the transportation sector, and soaring CO2 emissions necessitate the exploitation of renewable sources of energy. Despite the large variety of new energy Q3 carriers, liquid hydrocarbon still appears to be the most attractive and feasible form of transportation fuel taking into account the energy density, stability and existing infrastructure. Biomass is an abundant, renewable source of energy; however, utilizing it in a cost-effective way is still a substantial challenge. Lignocellulose is composed of three major biopolymers, namely cellulose, hemicellulose and lignin. Fast pyrolysis of biomass is recognized as an efficient and feasible process to selectively convert lignocellulose into a liquid fuelbio-oil. However bio-oil from fast pyrolysis contains a large amount of oxygen, distributed in hundreds of oxygenates. These oxygenates are the cause of many negative properties, such as low heating values, high corrosiveness, high viscosity, and instability; they also greatly Q4 limit the application of bio-oil particularly as transportation fuel. Hydrocarbons derived from biomass are most attractive because of their high energy density and compatibility with the existing infrastructure. Thus, converting lignocellulose into transportation fuels via catalytic fast pyrolysis has attracted much attention. Many studies related to catalytic fast pyrolysis of biomass have been published. The main challenge of this process is the development of active and stable catalysts that can deal with a large variety of decomposition intermediates from lignocellulose. This review starts with the current understanding of the chemistry in fast pyrolysis of lignocellulose and focuses on the development of catalysts in catalytic fast pyrolysis. Recent progress in the experimental studies on catalytic fast pyrolysis of biomass is also summarized with the emphasis on bio-oil yields and quality.

  5. Production of Ethanol from Cocoa Pod Hydrolysate

    Othman Abd Samah

    2011-07-01

    Full Text Available Cocoa pod (Theobroma cacao L. hydrolysate was hydrolyzed into glucose using hydrochloric, sulphuric and nitric acids, respectively. The concentration of each acid was set at 0.25 M, 0.50 M, 0.75 M, 1.00 M and 1.25 M. They were treated under two different temperatures and time at 75˚C and 90˚C for 2 h and 4 h, respectively. The results showed that hydrolysis in 1.00 M of hydrochloric acid at 75˚C for 4 h had produced the highest glucose content of 30.7% w/v compared to all others acids treated under similar conditions. The pod’s hydolysate was then fermented in batch culture using Saccharomyces cerevisiae for 48 h at 30˚C. A maximum ethanol production of 17.3%v/v was achieved after 26 h of fermentation time.

  6. Production d'éthanol a partir de biomasse lignocellulosique Ethanol Production from Lignocellulosic Biomass

    Ogier J. C.

    2006-12-01

    Full Text Available Cette étude fait le point des connaissances scientifiques et techniques dans le domaine de la production alcoolique à partir de susbstrats lignocellulosiques. Ce travail, réalisé dans le cadre d'Agrice (Agriculture pour la chimie et l'énergie, est une synthèse bibliographique qui a cherché à identifier les avancées capables de débloquer certains verrous technologiques et économiques liés à ce type de procédé. La biomasse lignocellulosique est un substrat complexe, constitué des trois principales fractions que sont la cellulose, les hémicelluloses et la lignine. Le procédé de production d'éthanol consiste à récupérer par hydrolyse le maximum de sucres issus à la fois des fractions cellulosiques et hémicellulosiques, puis de fermenter ces sucres en éthanol. Les premiers procédés d'hydrolyse utilisés étaient surtout chimiques, mais ils sont peu compétitifs à l'heure actuelle, en raison notamment du coût des réactifs et de la formation de nombreux sous-produits et de composés inhibiteurs rendant les hydrolysats peu fermentescibles. Ils sont désormais concurrencés par les procédés enzymatiques, plus spécifiques et qui permettent de meilleurs rendements d'hydrolyse dans des conditions moins sévères. Cependant, la biomasse lignocellulosique n'est pas directement accessible aux enzymes, et elle doit subir au préalable une phase de prétraitement dont l'objectif est d'améliorer la susceptibilité à l'hydrolyse enzymatique de la cellulose et éventuellement d'hydrolyser la fraction hémicellulosique en sucres monomères. Parmi les nombreuses méthodes de prétraitement qui ont été étudiées, nous en avons identifié trois répondant au mieux aux objectifs précédemment cités : le prétraitement à l'acide dilué, l'explosion à la vapeur avec utilisation d'un catalyseur, et la thermohydrolyse. Ces trois méthodes permettraient d'atteindre des rendements d'hydrolyse enzymatique de la cellulose proches de 100 %, tout en permettant un taux d'hydrolyse des hémicelluloses supérieur à 80 %, et en minimisant la formation de composés de dégradation. L'hydrolyse enzymatique doit encore être améliorée afin de réduire le coût lié à la consommation d'enzymes. Les principales voies de recherche devraient porter sur l'amélioration de l'activité des cellulases, afin de se rapprocher le plus possible de celles d'enzymes telles que les amylases. Le développement du procédé SFS (saccharification et fermentation simultanées permet d'améliorer l'efficacité des enzymes en minimisant les réactions d'inhibition des enzymes par les produits formés. Son inconvénient est lié aux différences entre les températures optimales de l'hydrolyse enzymatique et de la fermentation. La recherche de micro-organismes conservant de bonnes performances fermentaires à température élevée doit donc se poursuivre. Un autre verrou technologique du procédé concerne la fermentation alcoolique des pentoses, qui peuvent représenter jusqu'à 25 à 40 % des sucres totaux contenus dans la biomasse lignocellulosique. C'est pourquoi il est indispensable de les valoriser en éthanol. Contrairement à la fermentation alcoolique du glucose, largement connue et maîtrisée, celle des pentoses n'est toujours pas résolue, en raison des performances fermentaires médiocres des micro-organismes utilisés. Le développement des outils génétiques et les nouvelles voies de recherche portant sur la transformation de Saccharomyces cerevisiae et de Zymomonas mobilis afin de leur faire acquérir la capacité à fermenter les pentoses, devraient permettre d'améliorer les performances, et éventuellement de se rapprocher de celles enregistrées sur glucose par Saccharomyces Cette étude fait le point des connaissances scientifiques et techniques dans le domaine de la production alcoolique à partir de susbstrats lignocellulosiques. Ce travail, réalisé dans le cadre d'Agrice (Agriculture pour la chimie et l'énergie, est une synthèse bibliographique qui a cherché à identifier les avancées capables de débloquer certains verrous technologiques et économiques liés à ce type de procédé. La biomasse lignocellulosique est un substrat complexe, constitué des trois principales fractions que sont la cellulose, les hémicelluloses et la lignine. Le procédé de production d'éthanol consiste à récupérer par hydrolyse le maximum de sucres issus à la fois des fractions cellulosiques et hémicellulosiques, puis de fermenter ces sucres en éthanol. Les premiers procédés d'hydrolyse utilisés étaient surtout chimiques, mais ils sont peu compétitifs à l'heure actuelle, en raison notamment du coût des réactifs et de la formation de nombreux sous-produits et de composés inhibiteurs rendant les hydrolysats peu fermentescibles. Ils sont désormais concurrencés par les procédés enzymatiques, plus spécifiques et qui permettent de meilleurs rendements d'hydrolyse dans des conditions moins sévères. Cependant, la biomasse lignocellulosique n'est pas directement accessible aux enzymes, et elle doit subir au préalable une phase de prétraitement dont l'objectif est d'améliorer la susceptibilité à l'hydrolyse enzymatique de la cellulose et éventuellement d'hydrolyser la fraction hémicellulosique en sucres monomères. Parmi les nombreuses méthodes de prétraitement qui ont été étudiées, nous en avons identifié trois répondant au mieux aux objectifs précédemment cités : le prétraitement à l'acide dilué, l'explosion à la vapeur avec utilisation d'un catalyseur, et la thermohydrolyse. Ces trois méthodes permettraient d'atteindre des rendements d'hydrolyse enzymatique de la cellulose proches de 100 %, tout en permettant un taux d'hydrolyse des hémicelluloses supérieur à 80 %, et en minimisant la formation de composés de dégradation. L'hydrolyse enzymatique doit encore être améliorée afin de réduire le coût lié à la consommation d'enzymes. Les principales voies de recherche devraient porter sur l'amélioration de l'activité des cellulases, afin de se rapprocher le plus possible de celles d'enzymes telles que les amylases. Le développement du procédé SFS (saccharification et fermentation simultanées permet d'améliorer l'efficacité des enzymes en minimisant les réactions d'inhibition des enzymes par les produits formés. Son inconvénient est lié aux différences entre les températures optimales de l'hydrolyse enzymatique et de la fermentation. La recherche de micro-organismes conservant de bonnes performances fermentaires à température élevée doit donc se poursuivre. Un autre verrou technologique du procédé concerne la fermentation alcoolique des pentoses, qui peuvent représenter jusqu'à 25 à 40 % des sucres totaux contenus dans la biomasse lignocellulosique. C'est pourquoi il est indispensable de les valoriser en éthanol. Contrairement à la fermentation alcoolique du glucose, largement connue et maîtrisée, celle des pentoses n'est toujours pas résolue, en raison des performances fermentaires médiocres des micro-organismes utilisés. Le développement des outils génétiques et les nouvelles voies de recherche portant sur la transformation de Saccharomyces cerevisiae et de Zymomonas mobilis afin de leur faire acquérir la capacité à fermenter les pentoses, devraient permettre d'améliorer les performances, et éventuellement de se rapprocher de celles enregistrées sur glucose par Saccharomyces cerevisiae. The reported study intends to describe the state of the art in the domain of ethanol production from lignocellulosic biomass. It was sustained and managed by a specialized group of the French Agrice (Agriculture for Chemical and Energy Organization. Its first goal was to pinpoint the main technical and economical bottlenecks of the processes which are today under consideration, and to identify which research and development efforts could be implemented to overcome them (in the short or middle term. Lignocellulosic biomass is a complex substrate, and essentially made of cellulose, hemicellulose and lignin. The processes which have been considered, attempt to recover a maximum amount of sugars from the hydrolysis of cellulose and hemicellulose, and to ferment them into ethanol. The hydrolysis processes used in the past are essentially chemical processes, but the acid recovery costs and the formation of toxic products make them uncompetitive. They are now substituted by enzymatic processes, which are more specific and allow higher hydrolysis yields under less severe conditions. However, the cellulose that is the target of the enzymatic hydrolysis, is not directly accessible to the enzymes. It is the reason why a pretreatment step has to precede the enzymatic hydrolysis, in order to improve the enzymatic susceptibility of the cellulose, and to hydrolyse the hemicellulosic fraction. Different types of pretreatment have been studied, but three methods appear more efficient: dilute acid hydrolysis, steam explosion with catalyst addition and thermohydrolysis. These pretreatments could result in high hydrolysis yields of the cellulose fraction (close to 100%, and in a maximum recovery of the sugars from the hemicellulosic fraction. Enzymatic hydrolysis has yet to be improved in order to reduce the cost of consumption of the enzymes. Research works will have to focus upon the enzyme specific activity, in order to achieve higher efficiencies such as those obtained with amylases. The SSF (Saccharfication and Simultaneous Fermentation process improves the enzyme efficiency by reducing the feed-back inhibition from the hydrolysis products. The screening of efficient fermentative microorganisms under high temperature conditions (45°C has thus to be further implemented. The last technological barrier of the process concerns the ethanolic fermentation of the pentoses. Indeed, the pentoses, originating from the hemicellulosic fraction, can represent up to 40% of total sugars in some lignocellulosic substrates. Nobody has yet identified a microorganism which is able to ferment the pentoses into ethanol with performances similar to those of Saccharomyces cerevisiae on glucose. But recent genetic improvements focused on the transformation of Saccharomyces cerevisiae and Zymomonas mobilis could result in good fermentative performances on pentoses. The reported study intends to describe the state of the art in the domain of ethanol production from lignocellulosic biomass. It was sustained and managed by a specialized group of the French Agrice (Agriculture for Chemical and Energy Organization. Its first goal was to pinpoint the main technical and economical bottlenecks of the processes which are today under consideration, and to identify which research and development efforts could be implemented to overcome them (in the short or middle term. Lignocellulosic biomass is a complex substrate, and essentially made of cellulose, hemicellulose and lignin. The processes which have been considered, attempt to recover a maximum amount of sugars from the hydrolysis of cellulose and hemicellulose, and to ferment them into ethanol. The hydrolysis processes used in the past are essentially chemical processes, but the acid recovery costs and the formation of toxic products make them uncompetitive. They are now substituted by enzymatic processes, which are more specific and allow higher hydrolysis yields under less severe conditions. However, the cellulose that is the target of the enzymatic hydrolysis, is not directly accessible to the enzymes. It is the reason why a pretreatment step has to precede the enzymatic hydrolysis, in order to improve the enzymatic susceptibility of the cellulose, and to hydrolyse the hemicellulosic fraction. Different types of pretreatment have been studied, but three methods appear more efficient: dilute acid hydrolysis, steam explosion with catalyst addition and thermohydrolysis. These pretreatments could result in high hydrolysis yields of the cellulose fraction (close to 100%, and in a maximum recovery of the sugars from the hemicellulosic fraction. Enzymatic hydrolysis has yet to be improved in order to reduce the cost of consumption of the enzymes. Research works will have to focus upon the enzyme specific activity, in order to achieve higher efficiencies such as those obtained with amylases. The SSF (Saccharfication and Simultaneous Fermentation process improves the enzyme efficiency by reducing the feed-back inhibition from the hydrolysis products. The screening of efficient fermentative microorganisms under high temperature conditions (45°C has thus to be further implemented. The last technological barrier of the process concerns the ethanolic fermentation of the pentoses. Indeed, the pentoses, originating from the hemicellulosic fraction, can represent up to 40% of total sugars in some lignocellulosic substrates. Nobody has yet identified a microorganism which is able to ferment the pentoses into ethanol with performances similar to those of Saccharomyces cerevisiae on glucose. But recent genetic improvements focused on the transformation of Saccharomyces cerevisiae and Zymomonas mobilis could result in good fermentative performances on pentoses.

  7. Bioethanol from lignocellulose - pretreatment, enzyme immobilization and hydrolysis kinetics

    Tsai, Chien Tai; Anne S. Meyer; Johansen, Katja Salomon

    2012-01-01

    Forbehandling og enzymatisk hydrolyse er to af processerne involveret i produktionen af cellulosebaseret ethanol. Adskillige forbehandlings-strategier er foreslået, hvor nye forbehandlings-strategier udvikles til at øge effektiviteten af den enzymatiske hydrolyse. Prisen på enzymer er til stadighed en flaskehals i den enzymatiske hydrolyse, hvor genanvendelse af enzymerne er en mulig strategi for at reducere enzym-tilførslen i processen. Fra proces-ingeniørens synspunkt, er kinetikken bag enz...

  8. Advancing lignocellulose bioconversion through direct assessment of enzyme action on insoluble substrates

    Goacher, Robyn E.; Selig, Michael J.; Master, Emma R.

    2014-01-01

    Microbial utilization of lignocellulose from plant cell walls is integral to carbon cycling on Earth. Correspondingly, secreted enzymes that initiate lignocellulose depolymerization serve a crucial step in the bioconversion of lignocellulosic biomass to fuels and chemicals. Genome and metagenome ...

  9. Studies of Cellulosic Ethanol Production from Lignocellulose

    Moxley, Geoffrey W

    2007-01-01

    At present, the worldâ s transportation sector is being principally supplied by fossil fuels. However, energy consumption in this sector is drastically increasing and there are concerns with supply, cost, and environmental issues with the continuing use of fossil fuels. Utilizing non-petroleum ethanol in the transportation sector reduces the dependence on oil, and allows for cleaner burning of gasoline. Lignocellulose materials are structurally composed of five types of polymeric ...

  10. Lignocellulose as raw material in fermentation processes

    Mussatto, Solange I.; J. A. Teixeira

    2010-01-01

    Lignocellulose in the form of forestry, agricultural, and agro-industrial wastes is accumulated in large quantities every year. These materials are mainly composed of three groups of polymers, namely cellulose, hemicellulose, and lignin. Cellulose and hemicellulose are sugar rich fractions of interest for use in fermentation processes, since microorganisms may use the sugars for growth and production of value added compounds such as ethanol, food additives, organic acids, enzymes,...

  11. Conversion of Lignocellulosic Material into Fermentable Sugars

    Mohammed, Asem Hassan

    2012-01-01

    Die Umwandlung von Lignocellulose-Biomasse zu Biokraftstoffen ist eine vielversprechende Technologie, um diese einzigartige und nachhaltige Ressource zur Bereitstellung von umweltfreundlichen, organischen Brennstoffen und Chemikalien zu nutzen. Die meisten Projektionen zur globalen Energienutzung gehen davon aus, dass Biomasse eine wichtige Komponente der primären Energieversorgung in Zukunft sein wird. Hierbei stellt Agrarholz die primäre Quelle von Biomasse. Kurzumtrieb-Weidenholz (Salix sp...

  12. Oxidative pretreatment and biocatalytic valorization of lignocellulosic biomass

    Wiermans, Lotte

    2016-01-01

    In this PhD thesis, several novel (catalytic) approaches for lignocellulose valorization have been developed, using either lignocellulose, lignin, or other relevant biomass-derived platform chemicals. In the first section, the oxidative delignification of lignocellulose – using enzymatically in situ formed peracid – was studied on different natural resources in dimethyl carbonate (DMC) as solvent. Through that processing the formation of a yellowish lignin oil was observed, together with a de...

  13. Reparative properties of a commercial fish protein hydrolysate preparation

    FitzGerald, A J; Rai, P S; Marchbank, T; Taylor, G W; Ghosh, S.; Ritz, B W; Playford, R J

    2005-01-01

    Background: A partially hydrolysed and dried product of pacific whiting fish is currently marketed as a health food supplement to support intestinal health. However, there has been only limited scientific study regarding its true biological activity.

  14. Effect of Protein Hydrolysates on Pancreatic Cancer Cells

    Ossum, Carlo G.; Andersen, Lisa Lystbæk; Nielsen, Henrik Hauch; Hoffmann, Else K.; Jessen, Flemming

    Effect of Fish Protein Hydrolysates on Pancreatic Cancer Cells Carlo G. Ossum1, Lisa Lystbæk Andersen2, Henrik Hauch Nielsen2, Else K. Hoffmann1, and Flemming Jessen2 1University of Copenhagen, Department of Biology, Denmark, 2Technical University of Denmark (DTU), National Food Institute, Denmark...... Corresponding author: Carlo G. Ossum (cgossum@gmail.com) A large number of bioactive peptides have been identified in and isolated from various food sources. Milk seems to be a particularly rich source but also different fish species have been found to yield bioactive peptides. Bioactive peptides, usually...... hydrolysates obtained by enzymatic hydrolysis on cancer cell proliferation. Skin and belly flap muscle from trout were hydrolysed with the unspecific proteases Alcalase, Neutrase, or UE1 (all from Novozymes, Bagsværd, Denmark) to a hydrolysis degree of 1-15%. The hydrolysates were tested for biological...

  15. Biogas production from brewery spent grain enhanced by bioaugmentation with hydrolytic anaerobic bacteria.

    ?ater, Maa; Fanedl, Lijana; Malovrh, pela; Logar, Romana Marinek

    2015-06-01

    Lignocellulosic substrates are widely available but not easily applied in biogas production due to their poor anaerobic degradation. The effect of bioaugmentation by anaerobic hydrolytic bacteria on biogas production was determined by the biochemical methane potential assay. Microbial biomass from full scale upflow anaerobic sludge blanket reactor treating brewery wastewater was a source of active microorganisms and brewery spent grain a model lignocellulosic substrate. Ruminococcus flavefaciens 007C, Pseudobutyrivibrio xylanivorans Mz5(T), Fibrobacter succinogenes S85 and Clostridium cellulovorans as pure and mixed cultures were used to enhance the lignocellulose degradation and elevate the biogas production. P. xylanivorans Mz5(T) was the most successful in elevating methane production (+17.8%), followed by the coculture of P. xylanivorans Mz5(T) and F. succinogenes S85 (+6.9%) and the coculture of C. cellulovorans and F. succinogenes S85 (+4.9%). Changes in microbial community structure were detected by fingerprinting techniques. PMID:25836034

  16. The road to commercial lignocellulosic ethanol

    Fuglsang, C.C. [Novozymes Inc., Davis, CA (United States); Smith, M.T. [Novozymes North America, Franklinton, NC (United States); Mogensen, J. [Novozymes A/S, Bagsvaerd (Denmark); Lauridsen, C. [Novozymes China, Beijing (China)

    2009-07-01

    The transportation sector is the second largest energy user and the largest oil user. It has been estimated that by 2050, there will be 2.3 billion additional cars worldwide, of which 1.9 billion will be in developing countries. Global ethanol production is set to grow 12-fold between 2006 and 2030. Novozymes is a world leader in industrial enzymes and microorganisms. This presentation highlighted their commitment to the ethanol industry, with particular reference to its expertise in starch-based ethanol enzymes. The company works on various feedstocks and technologies with different partners in the United States, China, Brazil and Europe in order to enable the ethanol industry to commercialize lignocellulosic ethanol through cost efficient bioconversion. Novozymes processes are developed and integrated to make sustainable lignocellulosic ethanol production competitive with gasoline in the near term. Examples of Novozymes work on enzyme improvements were presented along with process developments. Full cost modeling demonstrated how these developments help bring down the cost of lignocellulosic ethanol to a cost competitive level. tabs., figs.

  17. Fungal Bioconversion of Lignocellulosic Residues; Opportunities & Perspectives

    Mehdi Dashtban, Heidi Schraft, Wensheng Qin

    2009-01-01

    Full Text Available The development of alternative energy technology is critically important because of the rising prices of crude oil, security issues regarding the oil supply, and environmental issues such as global warming and air pollution. Bioconversion of biomass has significant advantages over other alternative energy strategies because biomass is the most abundant and also the most renewable biomaterial on our planet. Bioconversion of lignocellulosic residues is initiated primarily by microorganisms such as fungi and bacteria which are capable of degrading lignocellulolytic materials. Fungi such as Trichoderma reesei and Aspergillus niger produce large amounts of extracellular cellulolytic enzymes, whereas bacterial and a few anaerobic fungal strains mostly produce cellulolytic enzymes in a complex called cellulosome, which is associated with the cell wall. In filamentous fungi, cellulolytic enzymes including endoglucanases, cellobiohydrolases (exoglucanases and β-glucosidases work efficiently on cellulolytic residues in a synergistic manner. In addition to cellulolytic/hemicellulolytic activities, higher fungi such as basidiomycetes (e.g. Phanerochaete chrysosporium have unique oxidative systems which together with ligninolytic enzymes are responsible for lignocellulose degradation. This review gives an overview of different fungal lignocellulolytic enzymatic systems including extracellular and cellulosome-associated in aerobic and anaerobic fungi, respectively. In addition, oxidative lignocellulose-degradation mechanisms of higher fungi are discussed. Moreover, this paper reviews the current status of the technology for bioconversion of biomass by fungi, with focus on mutagenesis, co-culturing and heterologous gene expression attempts to improve fungal lignocellulolytic activities to create robust fungal strains.

  18. Can lignocellulosic hydrocarbon liquids rival lignocellulose-derived ethanol as a future transport fuel?

    Yao Ding

    2012-11-01

    Full Text Available Although transport fuels are currently obtained mainly from petroleum, alternative fuels derived from lignocellulosic biomass (LB have drawn much attention in recent years in light of the limited reserves of crude oil and the associated environmental issues. Lignocellulosic ethanol (LE and lignocellulosic hydrocarbons (LH are two typical representatives of the LB-derived transport fuels. This editorial systematically compares LE and LB from production to their application in transport fuels. It can be demonstrated that LH has many advantages over LE relative to such uses. However, most recent studies on the production of the LB-derived transport fuels have focused on LE production. Hence, it is strongly recommended that more research should be aimed at developing an efficient and economically viable process for industrial LH production.

  19. Characterisation and foaming properties of hydrolysates derived from rapeseed isolate

    Larré, C.; Mulder, W J; Sánchez-Vioque, R.; Lazko, J.; Bérot, S.; Guéguen, J.; Popineau, Y.

    2006-01-01

    Two hydrolysis methods used to obtain rapeseed isolate derivates were compared: chemical hydrolysis performed under alkaline conditions and pepsic proteolysis performed under acidic conditions. The mean molecular weights obtained for the hydrolysates varied from 26 to 2.5 kDa, depending on the level of hydrolysis. Further characterisation showed that, at the same level of hydrolysis, the chemical hydrolysates differed by their charges and hydrophobicity from those derived from enzymatic diges...

  20. Production of lupinus angustifolius protein hydrolysates with improved functional properties

    Lqari, Hassane; Pedroche, Justo; Girón-Calle, Julio; Vioque, Javier; Millán, Francisco

    2005-01-01

    Protein hydrolysates were obtained from lupin flour and from the purified globulin a-conglutin, and their functional properties were studied. Hydrolysis with alcalase for 60 minutes yielded degrees of hydrolysis ranging from 4% to 11% for lupin flour, and from 4% to 13% for a-conglutin. Protein solubility, oil absorption, foam capacity and stability, emulsifying activity, and emulsion stability of hydrolysates with 6% degree of hydrolysis were determined and compared with the properties...

  1. Structural and Antihypertensive Properties of Enzymatic Hemp Seed Protein Hydrolysates

    Malomo, Sunday A.; John O. Onuh; Girgih, Abraham T.; Aluko, Rotimi E.

    2015-01-01

    The aim of this work was to produce antihypertensive protein hydrolysates through different forms of enzymatic hydrolysis (2% pepsin, 4% pepsin, 1% alcalase, 2% alcalase, 2% papain, and 2% pepsin + pancreatin) of hemp seed proteins (HSP). The hemp seed protein hydrolysates (HPHs) were tested for in vitro inhibitions of renin and angiotensin-converting enzyme (ACE), two of the enzymes that regulate human blood pressure. The HPHs were then administered orally (200 mg/kg body weight) to spontane...

  2. Processes for converting lignocellulosics to reduced acid pyrolysis oil

    Kocal, Joseph Anthony; Brandvold, Timothy A

    2015-01-06

    Processes for producing reduced acid lignocellulosic-derived pyrolysis oil are provided. In a process, lignocellulosic material is fed to a heating zone. A basic solid catalyst is delivered to the heating zone. The lignocellulosic material is pyrolyzed in the presence of the basic solid catalyst in the heating zone to create pyrolysis gases. The oxygen in the pyrolysis gases is catalytically converted to separable species in the heating zone. The pyrolysis gases are removed from the heating zone and are liquefied to form the reduced acid lignocellulosic-derived pyrolysis oil.

  3. Biological Production of a Hydrocarbon Fuel Intermediate Polyhydroxybutyrate (PHB) from a Process Relevant Lignocellulosic Derived Sugar (Poster)

    Wang, W.; Mittal, A.; Mohagheghi, A.; Johnson, D. K.

    2014-04-01

    PHAs are synthesized by many microorganisms to serve as intracellular carbon storage molecules. In some bacterial strains, PHB can account for up to 80% of cell mass. In addition to its application in the packaging sector, PHB also has great potential as an intermediate in the production of hydrocarbon fuels. PHB can be thermally depolymerized and decarboxylated to propene which can be upgraded to hydrocarbon fuels via commercial oligomerization technologies. Cupriavidus necator is the microorganism that has been most extensively studied and used for PHB production on an industrial scale; However the substrates used for producing PHB are mainly fructose, glucose, sucrose, fatty acids, glycerol, etc., which are expensive. In this study, we demonstrate production of PHB from a process relevant lignocellulosic derived sugar stream, i.e., saccharified slurry from pretreated corn stover. The strain was first investigated in shake flasks for its ability to utilize glucose, xylose and acetate. In addition, the strain was also grown on pretreated lignocellulose hydrolyzate slurry and evaluated in terms of cell growth, sugar utilization, PHB accumulation, etc. The mechanism of inhibition in the toxic hydrolysate generated by the pretreatment and saccharification process of biomass, was also studied.

  4. A novel fermentation strategy for removing the key inhibitor acetic acid and efficiently utilizing the mixed sugars from lignocellulosic hydrolysates

    Mark A. Eiteman PHD; Elliot Altman Phd

    2009-02-11

    As part of preliminary research efforts, we have completed several experiments which demonstrate 'proof of concept.' These experiments addressed the following three questions: (1) Can a synthetic mixed sugar solution of glucose and xylose be efficiently consumed using the multi-organism approach? (2) Can this approach be used to accumulate a model product? (3) Can this approach be applied to the removal of an inhibitor, acetate, selectively from mixtures of xylose and glucose? To answer the question of whether this multi-organism approach can effectively consume synthetic mixed sugar solutions, we first tested substrate-selective uptake using two strains, one unable to consume glucose and one unable to consume xylose. The xylose-selective strain ALS998 has mutations in the three genes involved in glucose uptake, rendering it unable to consume glucose: ptsG codes for the Enzyme IICB{sup Glc} of the phosphotransferase system (PTS) for carbohydrate transport (Postma et al., 1993), manZ codes for the IID{sup Man} domain of the mannose PTS permease (Huber, 1996), glk codes for glucokinase (Curtis and Epstein 1975) We also constructed strain ALS1008 which has a knockout in the xylA gene encoding for xylose isomerase, rendering ALS1008 unable to consume xylose. Two batch experiments and one continuous bioprocess were completed. In the first experiment, each strain was grown separately in a defined medium of 8 g/L xylose and 15 g/L glucose which represented xylose and glucose concentrations that can be generated by actual biomass. In the second experiment, the two strains were grown together in batch in the same defined, mixed-sugar medium. In a third experiment, we grew the strains continuously in a 'chemostat', except that we shifted the concentrations of glucose and xylose periodically to observe how the system would respond. (For example, we shifted the glucose concentration suddenly from 15 g/L to 30 g/L in the feed).

  5. Antioxidant Effect and Water-Holding Capacity of Roselle (Hibiscus sabdariffa L. Seed Protein Hydrolysates

    Fatoumata Tounkara

    2013-06-01

    Full Text Available The aim of this study was to investigate the effect of in-vitro pepsin and pancreatin digestion of proteins extracted from Roselle seed on the production of bioactive peptides. Defatted Roselle seed flour was used to extract different protein fractions namely globulin, albumin and glutelin. The proteins were digested using pepsin (1 h followed by pancreatin (1 h in order to produce hydrolysates with good antioxidant activity. The prepared hydrolysates were as effective as antioxidants in model systems, in scavenging of free radicals and acting as reducing agents. This effect was concentration-dependent and was also influenced by the type of protein fraction. The albumin fraction hydrolysates prepared showed the highest antioxidant activity followed by Glutelin and Globulin hydrolysates respectively (Albumin hydrolysates>Glutelin hydrolysates>Globulin hydrolysates. All of the prepared hydrolysates were also found to be effective in enhancing water-holding capacity and cooking yield in a meat model system. Albumin hydrolysates showed the highest improved meat cooking ability followed by Glutelin and Globulin respectively (Albumin hydrolysates>Glutelin hydrolysates>Globulin hydrolysates. The molecular weight distribution analysis of the hydrolysates was determined and most of the peptides were found between 1000 Da and below. The study findings suggest that Roselle seed protein hydrolysates can be applied as functional food ingredients and that their composition determines their functional properties thus their potential application in the food and feed industries.

  6. BIOCONVERSION OF WATER HYACINTH HYDROLYSATE INTO ETHANOL

    Sunita Bandopadhyay Mukhopadhyay

    2010-04-01

    Full Text Available The fast growing aquatic weed water hyacinth, which is available almost year-round in the tropics and subtropics, was utilized as the chief source of cellulose for production of fuel ethanol via enzymatic hydrolysis and fermentation. Fungal cellulases produced on-site by utilizing acid-alkali pretreated water hyacinth as the substrate were used as the crude enzyme source for hydrolysis of identically pretreated biomass. Four different modes of enzymatic hydrolysis and fermentation were trialed in the present study for optimization of the yield of ethanol. Two common yeasts viz., Saccharomyces cerevisiae and Pachysolen tannophilus, were used for fermentation of hexose and pentose sugars in the hydrolysate. Significant enhancement of concentration (8.3 g/L and yield (0.21 g/g of ethanol was obtained through a prefermentation hydrolysis-simultaneous saccharification and fermentation (PH-SSF process, over the other three processes viz., separate hydrolysis and fermentation (SHF, simultaneous saccharification and fermentation (SSF, and single batch bioconversion (SBB by utilizing fungal culture broth with and without filtration as crude enzyme source.

  7. Characterization of flavor of whey protein hydrolysates.

    Leksrisompong, Pattarin P; Miracle, R Evan; Drake, Maryanne

    2010-05-26

    Twenty-two whey protein hydrolysates (WPH) obtained from 8 major global manufacturers were characterized by instrumental analysis and descriptive sensory analysis. Proximate analysis, size exclusion chromatography, and two different degrees of hydrolysis (DH) analytical methods were also conducted. WPH were evaluated by a trained descriptive sensory panel, and volatile compounds were extracted by solid phase microextraction (SPME) followed by gas chromatography-mass spectrometry (GC-MS) and gas chromatography-olfactometry (GC-O). Eleven representative WPH were selected, and 15 aroma active compounds were quantified by GC-MS via the generation of external standard curves. Potato/brothy, malty, and animal flavors and bitter taste were key distinguishing sensory attributes of WPH. Correlations between bitter taste intensity, degree of hydrolysis (using both methods), and concentration of different molecular weight peptides were documented, with high DH samples having high bitter taste intensity and a high concentration of low molecular weight peptides and vice versa. The four aroma-active compounds out of 40 detected by GC-O present at the highest concentration and with consistently high odor activity values in WPH were Strecker derived products, dimethyl sulfide (DMS), 3-methyl butanal, 2-methyl butanal, and methional. Orthonasal thresholds of WPH were lower (p < 0.05) than basic taste thresholds suggesting that aromatics and bitter taste are both crucial to control in WPH food applications. PMID:20415487

  8. Bacterial biodegradation and bioconversion of industrial lignocellulosic streams.

    Mathews, Stephanie L; Pawlak, Joel; Grunden, Amy M

    2015-04-01

    Lignocellulose is a term for plant materials that are composed of matrices of cellulose, hemicellulose, and lignin. Lignocellulose is a renewable feedstock for many industries. Lignocellulosic materials are used for the production of paper, fuels, and chemicals. Typically, industry focuses on transforming the polysaccharides present in lignocellulose into products resulting in the incomplete use of this resource. The materials that are not completely used make up the underutilized streams of materials that contain cellulose, hemicellulose, and lignin. These underutilized streams have potential for conversion into valuable products. Treatment of these lignocellulosic streams with bacteria, which specifically degrade lignocellulose through the action of enzymes, offers a low-energy and low-cost method for biodegradation and bioconversion. This review describes lignocellulosic streams and summarizes different aspects of biological treatments including the bacteria isolated from lignocellulose-containing environments and enzymes which may be used for bioconversion. The chemicals produced during bioconversion can be used for a variety of products including adhesives, plastics, resins, food additives, and petrochemical replacements. PMID:25722022

  9. Laccase Enzymology in Relation to Lignocellulose Processing

    Sitarz, Anna Katarzyna; Meyer, Anne S; Mikkelsen, Jørn Dalgaard

    2013-01-01

    Adskillige studier har vist, at cellulase katalyseret nedbrydning af cellulose til glucose inhiberes af lignin og lignin-afledte phenoliske stoffer, som frigives under forbehandling af lignocellulose-biomasse. En forudsætning for optimering af enzymkatalyseret cellulose-til-glucose konvertering er derfor enten at fjerne de inhibitoriske stoffer eller at ændre dem på en sådan måde, at de ikke inhiberer den cellulase katalyserede cellulose-nedbrydning.Det primære fokus i det foreliggende PhD ar...

  10. Comparison of different pretreatment methods for separation hemicellulose from straw during the lignocellulosic bioethanol production

    Eisenhuber, Katharina; Krennhuber, Klaus; Steinmüller, Viktoria; Kahr, Heike; Jäger, Alexander

    2013-04-01

    The combustion of fossil fuels is responsible for 73% of carbon dioxide emissions into the atmosphere and consequently contributes to global warming. This fact has enormously increased the interest in the development of methods to reduce greenhouse gases. Therefore, the focus is on the production of biofuels from lignocellulosic agricultural residues. The feedstocks used for 2nd generation bioethanol production are lignocellulosic raw materials like different straw types or energy crops like miscanthus sinensis or arundo donax. Lignocellulose consists of hemicellulose (xylose and arabinose), which is bonded to cellulose (glucose) and lignin. Prior to an enzymatic hydrolysis of the polysaccharides and fermentation of the resulting sugars, the lignocelluloses must be pretreated to make the sugar polymers accessible to enzymes. A variety of pretreatment methods are described in the literature: thermophysical, acid-based and alkaline methods.In this study, we examined and compared the most important pretreatment methods: Steam explosion versus acid and alkaline pretreatment. Specific attention was paid to the mass balance, the recovery of C 5 sugars and consumption of chemicals needed for pretreatment. In lab scale experiments, wheat straw was either directly pretreated by steam explosion or by two different protocols. The straw was either soaked in sulfuric acid or in sodium hydroxide solution at different concentrations. For both methods, wheat straw was pretreated at 100°C for 30 minutes. Afterwards, the remaining straw was separated by vacuum filtration from the liquid fraction.The pretreated straw was neutralized, dried and enzymatically hydrolyzed. Finally, the sugar concentrations (glucose, xylose and arabinose) from filtrate and from hydrolysate were determined by HPLC. The recovery of xylose from hemicellulose was about 50% using the sulfuric acid pretreatment and less than 2% using the sodium hydroxide pretreatment. Increasing concentrations of sulfuric acid lead to increasing conversion of hemicellulose to xylose. In contrast, increasing sodium hydroxide concentrations degrade the hemicellulose to unknown derivates. Consequently, almost no sugars from hemicellulose remain for fermentation. The hydrolysis of sulfuric acid pretreated straw results in a maximum glucose concentration of 100 g/kg straw and a xylose concentration of nearly 30 g/kg. Sodium hydroxide pretreated and hydrolyzed straw leads to a maximum glucose concentration of 90 g/kg straw and a xylose concentration of nearly 20 g/kg. In comparison to the two chemical pretreatment methods (sodium hydroxide and sulfuric acid pretreatment), the steam explosion pretreatment (conditions: temperature 190°C, time 20 minutes) results in a higher glucose concentration of about 190 g/kg straw and a xylose concentration of nearly 75 g/kg straw after enzymatic hydrolysis of the dried straw. Because of the small effect the sodium hydroxide pretreatment has on xylose recovery, this method won't be used for separation and conversion of hemicellulose into xylose and arabinose. Although pretreatment with sulfuric acid achieved promising results, further research and economical considerations have to be performed. In conclusion, the steam explosion method is still the state of the art pretreatment method for the production of lignocellulosic biofuels. Alkaline methods destroy most of the xylose part of the sugar fraction and a loss of up to 25 % of the fermentable sugars is not acceptable for a sustainable biofuel production. The acid pretreatment yields high amounts of accessible hemicellulose and cellulose, but the consumption of chemicals for acid pretreatment and neutralization has to be taken into account when considering technical implementation.

  11. Chemical, functional, and structural properties of spent coffee grounds and coffee silverskin

    Ballesteros, Lina F.; J. A. TEIXEIRA; Mussatto, Solange I.

    2014-01-01

    Spent coffee grounds (SCG) and coffee silverskin (CS) represent a great pollution hazard if discharged into the environment. Taking this fact into account, the purpose of this study was to evaluate the chemical composition, functional properties, and structural characteristics of these agro-industrial residues in order to identify the characteristics that allow their reutilization in industrial processes. According to the results, SCG and CS are both of lignocellulosic nature. Sugars polymeri...

  12. Optimising the (Microwave) Hydrothermal Pretreatment of Brewers Spent Grains for Bioethanol Production

    Stuart Wilkinson; Smart, Katherine A; Cook, David J.

    2015-01-01

    For the production of bioethanol from lignocellulosic biomass, it is important to optimise the thermochemical pretreatment which is required to facilitate subsequent liberation of monomeric sugars. Here, we report optimisation of pretreatment conditions for brewers spent grains (BSG) with the main objectives of (1) working at commercially relevant high solids content, (2) minimising energy and chemical inputs, and (3) maximising downstream sugar yields. Studies indicated there to be a play-of...

  13. Physiological Importance and Mechanisms of Protein Hydrolysate Absorption

    Zhanghi, Brian M.; Matthews, James C.

    Understanding opportunities to maximize the efficient digestion and assimilation by production animals of plant- and animal-derived protein products is critical for farmers, nutritionists, and feed manufacturers to sustain and expand the affordable production of high quality animal products for human consumption. The challenge to nutritionists is to match gastrointestinal tract load to existing or ­inducible digestive and absorptive capacities. The challenge to feed manufacturers is to develop products that are efficient substrates for digestion, absorption, and/or both events. Ultimately, the efficient absorption of digesta proteins depends on the mediated passage (transport) of protein hydrosylate products as dipeptides and unbound amino acids across the lumen- and blood-facing membranes of intestinal absorptive cells. Data testing the relative efficiency of supplying protein as hydrolysates or specific dipeptides versus as free amino acids, and the response of animals in several physiological states to feeding of protein hydrolysates, are presented and reviewed in this chapter. Next, data describing the transport mechanisms responsible for absorbing protein hydrolysate digestion products, and the known and putative regulation of these mechanisms by their substrates (small peptides) and hormones are presented and reviewed. Several conclusions are drawn regarding the efficient use of protein hydrolysate-based diets for particular physiological states, the economically-practical application of which likely will depend on technological advances in the manufacture of protein hydrolysate products.

  14. Flash photolysis and pulse radiolysis studies on elastin hydrolysates.

    Sionkowska, Alina

    2013-08-01

    The formation of reactive species and free radicals in water soluble elastin hydrolysates have been investigated by pulse radiolysis and flash photolysis. Elastin hydrolysates were obtained by hydrolysis of elastin extracted from aorta. An investigation of the photochemical properties of elastin hydrolysates in water was carried out using nanosecond laser irradiation. The transient spectra of elastin hydrolysates solution excited at 266 nm showed two bands. One of them with maximum at 295 nm and the second one with maximum at 400 nm. The reactions of hydrated electrons and ?OH radicals with elastin have been studied by pulse radiolysis. In the absorption spectra of products resulting from the reaction of elastin with e(aq)(-) small maximum absorption in UV and visible light was observed. In the absorption spectra of products resulting from the reaction of the hydroxyl radicals with elastin two bands were observed. The first one at 320 nm and the second one at 410 nm. Reaction of OH radicals with elastin hydrolysates lead to formation of Tyr phenoxyl radicals with absorption at 410 nm. The influence of the addition of sodium azide NaN3 on the formation of the transients was evaluated. PMID:23702900

  15. Encapsulation-Induced Stress Helps Saccharomyces cerevisiae Resist Convertible Lignocellulose Derived Inhibitors

    Johan O. Westman

    2012-09-01

    Full Text Available The ability of macroencapsulated Saccharomyces cerevisiae CBS8066 to withstand readily and not readily in situ convertible lignocellulose-derived inhibitors was investigated in anaerobic batch cultivations. It was shown that encapsulation increased the tolerance against readily convertible furan aldehyde inhibitors and to dilute acid spruce hydrolysate, but not to organic acid inhibitors that cannot be metabolized anaerobically. Gene expression analysis showed that the protective effect arising from the encapsulation is evident also on the transcriptome level, as the expression of the stress-related genes YAP1, ATR1 and FLR1 was induced upon encapsulation. The transcript levels were increased due to encapsulation already in the medium without added inhibitors, indicating that the cells sensed low stress level arising from the encapsulation itself. We present a model, where the stress response is induced by nutrient limitation, that this helps the cells to cope with the increased stress added by a toxic medium, and that superficial cells in the capsules degrade convertible inhibitors, alleviating the inhibition for the cells deeper in the capsule.

  16. Impacts of lignocellulose-derived inhibitors on L-lactic acid fermentation by Rhizopus oryzae.

    Zhang, Li; Li, Xin; Yong, Qiang; Yang, Shang-Tian; Ouyang, Jia; Yu, Shiyuan

    2016-03-01

    Inhibitors generated in the pretreatment and hydrolysis of corn stover and corn cob were identified. In general, they inhibited cell growth, lactate dehydrogenase, and lactic acid production but with less or no adverse effect on alcohol dehydrogenase and ethanol production in batch fermentation by Rhizopus oryzae. Furfural and 5-hydroxymethyl furfural (HMF) were highly toxic at 0.5-1 g L(-1), while formic and acetic acids at less than 4 g L(-1) and levulinic acid at 10 g L(-1) were not toxic. Among the phenolic compounds at 1 g L(-1), trans-cinnamic acid and syringaldehyde had the highest toxicity while syringic, ferulic and p-coumaric acids were not toxic. Although these inhibitors were present at concentrations much lower than their separately identified toxic levels, lactic acid fermentation with the hydrolysates showed much inferior performance compared to the control without inhibitor, suggesting synergistic or compounded effects of the lignocellulose-degraded compounds on inhibiting lactic acid fermentation. PMID:26724548

  17. Understanding ?-mannanase from Streptomyces sp. CS147 and its potential application in lignocellulose based biorefining.

    Yoo, Hah Y; Pradeep, G C; Lee, Soo K; Park, Don H; Cho, Seung S; Choi, Yun H; Yoo, Jin C; Kim, Seung W

    2015-12-01

    Hydrolytic enzymes such as cellulase and hemicellulase have been attracted in lignocellulose based biorefinery. Especially, mannanase has been a growing interest in industrial applications due to its importance in the bioconversion. In this study, an extracellular endo-?-1,4-D-mannanase was produced by Streptomyces sp. CS147 (Mn147) and purified 8.5-fold with a 43.4% yield using Sephadex G-50 column. The characterization of Mn147 was performed, and the results were as follows: molecular weight of ?25 kDa with an optimum temperature of 50C and pH of 11.0. The effect of metal ions and various reagents on Mn147 was strongly activated by Ca(+2) but inhibited by Mg(+2) , Fe(+2) , hydrogen peroxide, EDTA and EGTA. Km and Vmax values of Mn147 were 0.13 mg/mL and 294 ?mol/min mg, respectively, when different concentrations (3.1 to 50 mg/mL) of locust bean gum galactomannan were used as substrate. In enzymatic hydrolysis of heterogeneous substrate (spent coffee grounds), Mn147 shows a similar conversion compared to commercial enzymes. In addition, lignocellulosic biomass can be hydrolyzed to oligosaccharides (reducing sugars), which can be further utilized for the production of biomaterials. These results showed that Mn147 is attractive in quest of potential bioindustrial applications. PMID:26479417

  18. Enzymology of lignocellulose bioconversion by Streptomyces viridosporus

    Significant progress has been made in lignin biodegradation research since 1983, when lignin peroxidases were discovered in fungi. A similar breakthrough in bacterial lignin biodegradation research is anticipated. Several laboratories have successfully demonstrated the ability of bacteria to mineralize [14C]-lignin lignocelluloses as well as 14C-labelled synthetic lignins. Attempts are being made to identify the key enzymes involved. In this dissertation, two studies are presented which address the enzymology of lignin biodegradation by Streptomyces viridosporus. The first study compares selected extracellular enzyme of wild-type and genetically manipulated strains with enhanced abilities to produced a water soluble lignin degradation intermediate, designated acid-precipitable polymeric lignin (APPL). UV irradiation mutant T7A-81 and protoplast fusion recombinant SR-10 had higher and longer persisting peroxidase, esterase, and endoglucanase activity than did the wild type strain T7A. An extracellular lignocellulose-induced peroxidase with some similarities to fungal ligninases was described for the first time in Streptomyces. The second study describes purification and characterization of an extracellular lignin peroxidase produced by S. viridosporus T7A. This is the first report of a lignin peroxidase in any bacterium

  19. Electricity generation by microbial fuel cells fuelled with wheat straw hydrolysate

    Thygesen, Anders; Poulsen, Finn Willy; Angelidaki, Irini; Min, Booki; Thomsen, Anne Belinda

    2011-01-01

    Electricity production from microbial fuel cells fueled with hydrolysate produced by hydrothermal treatment of wheat straw can achieve both energy production and domestic wastewater purification. The hydrolysate contained mainly xylan, carboxylic acids, and phenolic compounds. Power generation and...

  20. Production of enzymatic protein hydrolysates from freshwater catfish (Clarias batrachus)

    Seniman, Maizatul Sarah Md; Yusop, Salma Mohamad; Babji, Abdul Salam

    2014-09-01

    Fish protein hydrolysate (FPH) was prepared from freshwater catfish (Clarias batrachus) by using Alcalase® 2.4L and Papain. The effect of hydrolysis time (30, 60, 120, 180 min) with enzyme concentration of 1% (v/w substrate); pH = 8.0, 7.0 was studied to determine the degree of hydrolysis (DH), peptide content, proximate composition and amino acid profile. Results showed that the highest DH of Alcalase and Papain FPH were 58.79% and 53.48% after 180 min at 55°C incubation respectively. The peptide content of both FPH increased as hydrolysis time increases. FPH showed higher crude protein content and lower fat, moisture and ash content compared to raw catfish. The major amino acids of both hydrolysates were Glu, Lys and Asp. Content of essential amino acids of Alcalase and Papain hydrolysates were 44.05% and 43.31% respectively.

  1. Enzyme Hydrolysates from Stichopus horrens as a New Source for Angiotensin-Converting Enzyme Inhibitory Peptides

    Bita Forghani; Afshin Ebrahimpour; Jamilah Bakar; Azizah Abdul Hamid; Zaiton Hassan; Nazamid Saari

    2012-01-01

    Stichopus horrens flesh was explored as a potential source for generating peptides with angiotensin-converting enzyme (ACE) inhibitory capacity using 6 proteases, namely alcalase, flavourzyme, trypsin, papain, bromelain, and protamex. Degree of hydrolysis (DH) and peptide profiling (SDS-PAGE) of Stichopus horrens hydrolysates (SHHs) was also assessed. Alcalase hydrolysate showed the highest DH value (39.8%) followed by flavourzyme hydrolysate (32.7%). Overall, alcalase hydrolysate exhibited t...

  2. Factors affecting antioxidant activity of soybean meal and caseine protein hydrolysates

    Antioxidative activity of protein hydrolysates was dependent on the raw material, condition of hydrolysis and lipid substrate used in model systems. Soybean meal hydrolysate was more active in lard and in linoleic acid emulsion than caseine hydrolysate, whereas caseine was more active in vegetable oils. Antioxidant activity of evaluated protein hydrolysates in all lipid systems, with or without oxidation catalysts, suggests them as natural food additives for lipid stabilization, thus for improvement of its nutritional value and sensory properties

  3. Alternatives for spent fuel

    During the past year, the National Waste Policy Act (NWPA) of 1982 has been directing the Federal Government's programs in the area of spent fuel and high level wastes. In addition, this legislation has greatly influenced utility spent fuel management planning. Final disposition of spent fuel is provided in the NWPA through geological repositories. The producers of spent fuel are responsible however, for its storage until a repository or federal Monitored Retrievable Storage (MRS) facility is available. There are several alternatives for interim storage of spent fuel prior to final disposition: wet pools, dry casks, dry wells, and dry storage vaults. Spent fuel pool storage is a widely used technology which has demonstrated safe storage of spent fuel for several decades. Pool storage at reactors has been enhanced in the past by the use of high density storage racks. In the future, spent fuel rod consolidation will further increase the capacity of reactor pool storage. Independent spent fuel pool facilities can provide economic storage capacity beyond that provided by the reactor pools. The first design and license application for such a facility meeting current requirements was completed by G/C in mid 1983

  4. Reviving the carbohydrate economy via multi-product lignocellulose biorefineries.

    Zhang, Y-H Percival

    2008-05-01

    Before the industrial revolution, the global economy was largely based on living carbon from plants. Now the economy is mainly dependent on fossil fuels (dead carbon). Biomass is the only sustainable bioresource that can provide sufficient transportation fuels and renewable materials at the same time. Cellulosic ethanol production from less costly and most abundant lignocellulose is confronted with three main obstacles: (1) high processing costs (dollars /gallon of ethanol), (2) huge capital investment (dollars approximately 4-10/gallon of annual ethanol production capacity), and (3) a narrow margin between feedstock and product prices. Both lignocellulose fractionation technology and effective co-utilization of acetic acid, lignin and hemicellulose will be vital to the realization of profitable lignocellulose biorefineries, since co-product revenues would increase the margin up to 6.2-fold, where all purified lignocellulose co-components have higher selling prices (> approximately 1.0/kg) than ethanol ( approximately 0.5/kg of ethanol). Isolation of large amounts of lignocellulose components through lignocellulose fractionation would stimulate R&D in lignin and hemicellulose applications, as well as promote new markets for lignin- and hemicellulose-derivative products. Lignocellulose resource would be sufficient to replace significant fractionations (e.g., 30%) of transportation fuels through liquid biofuels, internal combustion engines in the short term, and would provide 100% transportation fuels by sugar-hydrogen-fuel cell systems in the long term. PMID:18180967

  5. Iron-chelating activity of chickpea protein hydrolysate peptides.

    Torres-Fuentes, Cristina; Alaiz, Manuel; Vioque, Javier

    2012-10-01

    Chickpea-chelating peptides were purified and analysed for their iron-chelating activity. These peptides were purified after affinity and gel filtration chromatography from a chickpea protein hydrolysate produced with pepsin and pancreatin. Iron-chelating activity was higher in purified peptide fractions than in the original hydrolysate. Histidine contents were positively correlated with the iron-chelating activity. Hence fractions with histidine contents above 20% showed the highest chelating activity. These results show that iron-chelating peptides are generated after chickpea protein hydrolysis with pepsin plus pancreatin. These peptides, through metal chelation, may increase iron solubility and bioavailability and improve iron absorption. PMID:25005984

  6. The Effects of Mechanically Deboned Chicken Hydrolysates on the Characteristics of Imitation Crab Stick.

    Jin, Sang-Keun; Hwang, Jin-Won; Moon, Sungsil; Choi, Yeung-Joon; Kim, Gap-Don; Jung, Eun-Young; Yang, Han-Sul

    2014-01-01

    The effects of adding mechanically deboned chicken (MDC) hydrolysates on the quality characteristics of imitation crab stick (ICS) during storage were investigated. ICS was prepared from Alaska Pollack, chicken breast surimi, and protein hydrolysates enzymatically extracted from MDC. ICS samples were divided into 4 groups: without protein hydrolysate (control), added with 0.5% protein hydrolysate (T1), added with 1.0% protein hydrolysate (T2), and added with 1.5% protein hydrolysate (T3). Results showed that crude protein content did not differ significantly among the ICS samples (p>0.05). ICS sample added with MDC hydrolysates had higher crude fat and ash content but lower moisture content than the control (p<0.05). Lightness was significantly lower in T2 and T3 than in the other groups at 0 and 4 wk of storage. Also, whiteness decreased in the groups contained MDC hydrolysates. Breaking force and jelly strength were higher in samples containing MDC hydrolysates compared to control samples (p<0.05). Additionally, saturated fatty acid contents were lower in the groups containing MDC hydrolysates than in control sample groups (p<0.05). Polyunsaturated fatty acid (PUFA) and essential fatty acids (EFA) were significantly higher in T2 and T3 than the control samples. In particular, all samples containing MDC hydrolysates had reduced thiobarbituric acid-reactive substances (TBARS) values at 4 wk. Free radical scavenging activity also was increased with addition of MDC hydrolysates. PMID:26760938

  7. Possible application of brewer’s spent grain in biotechnology

    Pejin Jelena D.

    2013-01-01

    Full Text Available Brewer’s spent grain is the major by-product in beer production. It is produced in large quantities (20 kg per 100 liters of produced beer throughout the year at a low cost or no cost, and due to its high protein and carbohydrates content it can be used as a raw material in biotechnology. Biotechnological processes based on renewable agro-industrial by-products have ecological (zero CO2 emission, eco-friendly by-products and economical (cheap raw materials and reduction of storage costs advantages. The use of brewer’s spent grain is still limited, being basically used as animal feed. Researchers are trying to improve the application of brewer’s spent grain by finding alternative uses apart from the current general use as an animal feed. Its possible applications are in human nutrition, as a raw material in biotechnology, energy production, charcoal production, paper manufacture, as a brick component, and adsorbent. In biotechnology brewer’s spent grain could be used as a substrate for cultivation of microorganisms and enzyme production, additive of yeast carrier in beer fermentation, raw material in production of lactic acid, bioethanol, biogas, phenolic acids, xylitol, and pullulan. Some possible applications for brewer’s spent grain are described in this article including pre-treatment conditions (different procedures for polysaccharides, hemicelluloses, and cellulose hydrolysis, working microorganisms, fermentation parameters and obtained yields. The chemical composition of brewer’s spent grain varies according to barley variety, harvesting time, malting and mashing conditions, and a quality and type of unmalted raw material used in beer production. Brewer’s spent grain is lignocellulosic material rich in protein and fibre, which account for approximately 20 and 70% of its composition, respectively.

  8. Screening and characteristics of a butanol-tolerant strain and butanol production from enzymatic hydrolysate of NaOH-pretreated corn stover.

    Gao, Kai; Li, Yun; Tian, Shen; Yang, Xiushan

    2012-10-01

    As a gasoline substitute, butanol has advantages over traditional fuel ethanol in terms of energy density and hydroscopicity. However, solvent production appeared limited by butanol toxicity. The strain of Clostridium acetobutylicum was subjected to mutation by mutagen of N-methyl-N'-nitro-N-nitrosoguanidine for 0.5h. Screening of mutants was done according to the individual resistance to butanol. A selected butanol-resistant mutant, strain 206, produced 50% higher solvent concentrations than the wild-type strain when 60g glucose/l was employed as substrate. The strain was also able to produce solvents of 23.47g/l in 80g/l glucose P2 medium after 70h fermentation, including 5.41g acetone/l, 15.05g butanol/l and 3.02g ethanol/l, resulting in an ABE yield and productivity of 0.32g/g and 0.34g/(lh). Subsequently, Acetone-butanol-ethanol (ABE) production from enzymatic hydrolysate of NaOH-pretreated corn stover was investigated in this study. An ABE yield of 0.41 and a productivity of 0.21g/(lh) was obtained, compared to the yield of 0.33 and the productivity of 0.20g/(lh) in the control medium containing 52.47 mixed sugars. However, it is important to note that although strain 206 was able to utilize all the glucose rapidly in the hydrolysate, only 32.9% xylose in the hydrolysate was used after fermentation stopped compared to 91.4% xylose in the control medium. Strain 206 was shown to be a robust strain for ABE production from lignocellulosic materials and has a great potential for industrial application. PMID:22806737

  9. Superhydrophobic lignocellulosic wood fiber/mineral networks.

    Mirvakili, Mehr Negar; Hatzikiriakos, Savvas G; Englezos, Peter

    2013-09-25

    Lignocellulosic wood fibers and mineral fillers (calcium carbonate, talc, or clay) were used to prepare paper samples (handsheets), which were then subjected to a fluorocarbon plasma treatment. The plasma treatment was performed in two steps: first using oxygen plasma to create nanoscale roughness on the surface of the handsheet, and second fluorocarbon deposition plasma to add a layer of low surface energy material. The wetting behavior of the resulting fiber/mineral network (handsheet) was determined. It was found the samples that were subjected to oxygen plasma etching prior to fluorocarbon deposition exhibit superhydrophobicity with low contact angle hysteresis. On the other hand, those that were only treated by fluorocarbon plasma resulted in "sticky" hydrophobicity behavior. Moreover, as the mineral content in the handsheet increases, the hydrophobicity after plasma treatment decreases. Finally, it was found that although the plasma-treated handsheets show excellent water repellency they are not good water vapor barriers. PMID:23957774

  10. Extrusion Pretreatment of Lignocellulosic Biomass: A Review

    Jun Zheng

    2014-10-01

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

  11. Radiation hydrolysate of tuna cooking juice with enhanced antioxidant properties

    Tuna protein hydrolysates are of increasing interest because of their potential application as a source of bioactive peptides. Large amounts of tuna cooking juice with proteins and extracts are produced during the process of tuna canning, and these cooking juice wastes cause environmental problems. Therefore, in this study, cooking juice proteins were hydrolyzed by irradiation for their utilization as functional additives. The degree of hydrolysis of tuna cooking juice protein increased from 0% to 15.1% at the absorbed doses of 50 kGy. To investigate the antioxidant activity of the hydrolysate, it was performed the ferric reducing antioxidant power (FRAP) assay, and the lipid peroxidation inhibitory and superoxide radical scavenging activities were measured. The FRAP values increased from 1470 μM to 1930 μM and IC50 on superoxide anion was decreased from 3.91 μg/mL to 1.29 μg/mL at 50 kGy. All of the antioxidant activities were increased in the hydrolysate, suggesting that radiation hydrolysis, which is a simple process that does not require an additive catalysts or an inactivation step, is a promising method for food and environmental industries. - Highlights: ► Radiation was applied for the hydrolysis of tuna cooking juice protein. ► The degree of hydrolysis were increased by irradiation and the antioxidant activity of hydrolysate was higher than protein. ► This result suggest that radiation is useful method for the hydrolysis of protein.

  12. Selection of the Strain Lactobacillus acidophilus ATCC 43121 and Its Application to Brewers' Spent Grain Conversion into Lactic Acid

    Liguori, Rossana; Soccol, Carlos Ricardo; Vandenberghe, Luciana Porto de Souza; Woiciechowski, Adenise Lorenci; Ionata, Elena; Marcolongo, Loredana; Faraco, Vincenza

    2015-01-01

    Six Lactobacillus strains were analyzed to select a bacterium for conversion of brewers' spent grain (BSG) into lactic acid. Among the investigated strains, L. acidophilus ATCC 43121 showed the highest yield of lactic acid production (16.1?g/L after 48 hours) when grown in a synthetic medium. It was then analyzed for its ability to grow on the hydrolysates obtained from BSG after acid-alkaline (AAT) or aqueous ammonia soaking (AAS) pretreatment. The lactic acid production by L. acidophilus ATCC 43121 through fermentation of the hydrolysate from AAS treated BSG was 96% higher than that from the AAT treated one, although similar yields of lactic acid per consumed glucose were achieved due to a higher (46%) glucose consumption by L. acidophilus ATCC 43121 in the AAS BSG hydrolysate. It is worth noting that adding yeast extract to the BSG hydrolysates increased both the yield of lactic acid per substrate consumed and the volumetric productivity. The best results were obtained by fermentation of AAS BSG hydrolysate supplemented by yeast extract, in which the strain produced 22.16?g/L of lactic acid (yield of 0.61?g/g), 27% higher than the value (17.49?g/L) obtained in the absence of a nitrogen source. PMID:26640784

  13. Generation and identification of angiotensin converting enzyme (ACE) inhibitory peptides from a brewers' spent grain protein isolate.

    Connolly, Alan; O'Keeffe, Martina B; Piggott, Charles O; Nongonierma, Alice B; FitzGerald, Richard J

    2015-06-01

    An alkaline extracted brewers' spent grain protein-enriched isolate (BSG-PI) was hydrolysed using Alcalase, Corolase PP, Flavourzyme and Promod 144MG, yielding Alc hydrolysate (H), CorH, FlavH and ProH, respectively. The degree of hydrolysis (DH) of the protein hydrolysates varied from 4.45% for ProH to 16.4% for CorH. The in vitro ACE inhibitory activity of the BSG-PI increased significantly following 15min incubations with Alcalase, Corolase PP and Flavourzyme. The 5kDa ultrafiltration permeates of FlavH and CorH resulted in lower ACE IC50 values than their respective hydrolysates. The bioactivity of the BSG-PI hydrolysates was retained after simulated gastrointestinal digestion (SGID) while SGID also resulted in the release of ACE inhibitory peptides from the BSG-PI and ProH. UPLC-MS/MS analysis resulted in the identification of 34 peptides. Of 12 synthesised peptides, IVY and ILDL were the most potent, having ACE IC50 values at 80.411.9 and 96.48.36?M, respectively. PMID:25624207

  14. Selection of the Strain Lactobacillus acidophilus ATCC 43121 and Its Application to Brewers' Spent Grain Conversion into Lactic Acid.

    Liguori, Rossana; Soccol, Carlos Ricardo; Vandenberghe, Luciana Porto de Souza; Woiciechowski, Adenise Lorenci; Ionata, Elena; Marcolongo, Loredana; Faraco, Vincenza

    2015-01-01

    Six Lactobacillus strains were analyzed to select a bacterium for conversion of brewers' spent grain (BSG) into lactic acid. Among the investigated strains, L. acidophilus ATCC 43121 showed the highest yield of lactic acid production (16.1?g/L after 48 hours) when grown in a synthetic medium. It was then analyzed for its ability to grow on the hydrolysates obtained from BSG after acid-alkaline (AAT) or aqueous ammonia soaking (AAS) pretreatment. The lactic acid production by L. acidophilus ATCC 43121 through fermentation of the hydrolysate from AAS treated BSG was 96% higher than that from the AAT treated one, although similar yields of lactic acid per consumed glucose were achieved due to a higher (46%) glucose consumption by L. acidophilus ATCC 43121 in the AAS BSG hydrolysate. It is worth noting that adding yeast extract to the BSG hydrolysates increased both the yield of lactic acid per substrate consumed and the volumetric productivity. The best results were obtained by fermentation of AAS BSG hydrolysate supplemented by yeast extract, in which the strain produced 22.16?g/L of lactic acid (yield of 0.61?g/g), 27% higher than the value (17.49?g/L) obtained in the absence of a nitrogen source. PMID:26640784

  15. Protein hydrolysates and recovery of muscle damage following eccentric exercise

    Dale M.J.

    2015-01-01

    Full Text Available Background: A whey protein hydrolysate (NatraBoost XR; WPHNB has been shown to speed repair muscle damage. We sought to determine whether this benefit is specific to this hydrolysate to evaluate a marker for quality control. Methods: Three hydrolysates of the same whey protein isolate (WPI were prepared (WPHNB, WPH1 and WPH2. Isometric knee extensor strength was measured in 39 sedentary male participants before and after 100 maximal eccentric contractions of the knee extensors to induce muscle damage. Participants were then randomised to consume 250 ml of flavoured water (FW, n=9, or 250 ml of FW containing 25 g of either NatraBoost XR (n=3, WPH1 (n=9, WPH2 (n=9 or WPI (n=9. Strength was reassessed over the next seven days while the supplements were consumed daily. Fibroblasts were cultured for 48 hr in the presence of the different hydrolysates, WPI, saline or fetal bovine serum to ascertain effects on cell proliferation. Results: Strength was reduced in all treatment groups after eccentric exercise (P<0.001. Strength recovered steadily over 7 days in the FW, WPI, WPH1 and WPH2 treatment groups (P<0.001, with no difference between treatments (P=0.87. WPHNB promoted faster strength recovery compared with the other treatments (P<0.001. Fibroblast proliferation was greater with WPHNB compared with saline, WPI or the other hydrolysates (P<0.001. Conclusions: Promoting recovery from muscle damage seems unique to WPHNB. In vitro fibroblast proliferation may be a useful marker for quality control. It is not clear whether effects on fibroblast proliferation contribute to the in vivo effect of WPHNB on muscle damage.

  16. Protein Hydrolysates as Hypoallergenic, Flavors and Palatants for Companion Animals

    Nagodawithana, Tilak W.; Nelles, Lynn; Trivedi, Nayan B.

    Early civilizations have relied upon their good sense and experience to develop and improve their food quality. The discovery of soy sauce centuries ago can now be considered one of the earliest protein hydrolysates made by man to improve palatability of foods. Now, it is well known that such savory systems are not just sources for enjoyment but complex semiotic systems that direct the humans to satisfy the body's protein need for their sustenance. Recent developments have resulted in a wide range of cost effective savory flavorings, the best known of which are autolyzed yeast extracts and hydrolyzed vegetable proteins. New technologies have helped researchers to improve the savory characteristics of yeast extracts through the application of Maillard reaction and by generating specific flavor enhancers through the use of enzymes. An interesting parallel exists in the pet food industry, where a similar approach is taken in using animal protein hydrolysates to create palatability enhancers via Maillard reaction scheme. Protein hydrolysates are also utilized extensively as a source of nutrition to the elderly, young children and immuno-compromised patient population. These hydrolysates have an added advantage in having peptides small enough to avoid any chance of an allergenic reaction which sometimes occur with the consumption of larger sized peptides or proteins. Accordingly, protein hydrolysates are required to have an average molecular weight distribution in the range 800-1,500 Da to make them non-allergenic. The technical challenge for scientists involved in food and feed manufacture is to use an appropriate combination of enzymes within the existing economic constraints and other physical factors/limitations, such as heat, pH, and time, to create highly palatable, yet still nutritious and hypoallergenic food formulations.

  17. Production of Lupinus angustifolius protein hydrolysates with improved functional properties

    Millán, Francisco

    2005-06-01

    Full Text Available Protein hydrolysates wer e obtained from lupin flour and from the purified globulin α -conglutin, and their functional properties were studied. Hydrolysis with alcalase for 60 minutes yielded degrees of hydrolysis ranging from 4 % to 11 % for lupin flour, and from 4 % to 13% for α -conglutin. Protein solubility, oil absorption, foam capacity and stability, emulsifying activity, and emulsion stability of hydrolysates with 6% degree of hydrolysis were determined and compared with the properties of the original flour. The protein hydrolysates showed better functional properties than the original proteins. Most importantly, the solubility of the α -conglutin and L. angustifolius flour hydrolysates was increased by 43 % and 52 %, respectively. Thus, lupin seed protein hydrolysates have improved functional properties and could be used in the elaboration of a variety of products such as breads, cakes, and salad dressings.Se obtuvieron hidrolizados proteicos de la harina del altramuz y de la globulina α - conglutina purificada y se estudiaron sus propiedades funcionales. La hidrólisis con alcalasa durante 60 minutos produjo hidrolizados con grados de hidrólisis entre el 4 % y el 11 % para la harina y entre el 4 % y el 13 % para la α - conglutina. Se estudió en un hidrolizado con un 6 % de grado de hidrólisis la solubilidad proteica, absorción de aceite, capacidad y estabilidad espumante y actividad y estabilidad emulsificante. Los hidrolizados proteicos mostraron mejores propiedades funcionales que las proteínas originales. Más aún, la solubilidad de los hidrolizados de α - conglutina y la harina se incrementó en un 43 % y 52 % respectivamente. Así pues, hidrolizados de proteínas de semilla de lupino presentan mejores propiedades funcionales y podrían usarse en la elaboración de productos como pan, dulces, salsas o cremas.

  18. Enzymatic lignocellulose hydrolysis: Improved cellulase productivity by insoluble solids recycling.

    Weiss Noah; Brjesson Johan; Pedersen Lars Saaby; Meyer Anne S

    2013-01-01

    Abstract Background It is necessary to develop efficient methods to produce renewable fuels from lignocellulosic biomass. One of the main challenges to the industrialization of lignocellulose conversion processes is the large amount of cellulase enzymes used for the hydrolysis of cellulose. One method for decreasing the amount of enzyme used is to recycle the enzymes. In this study, the recycle of enzymes associated with the insoluble solid fraction after the enzymatic hydrolysis of cellulose...

  19. The chemistry involved in the steam treatment of lignocellulosic materials

    Luiz Pereira Ramos

    2003-01-01

    Pretreatment of lignocellulosic materials is essential for bioconversion because of the various physical and chemical barriers that greatly inhibit their susceptibility to bioprocesses such as hydrolysis and fermentation. The aim of this article is to review some of the most important pretreatment methods developed to date to enhance the conversion of lignocellulosics. Steam explosion, which precludes the treatment of biomass with high-pressure steam under optimal conditions, is presented as ...

  20. Lignin triggers irreversible cellulase loss during pretreated lignocellulosic biomass saccharification

    Gao, Dahai; Haarmeyer, Carolyn; Balan, Venkatesh; Whitehead, Timothy A.; Dale, Bruce E.; Chundawat, Shishir PS

    2014-01-01

    Background Non-productive binding of enzymes to lignin is thought to impede the saccharification efficiency of pretreated lignocellulosic biomass to fermentable sugars. Due to a lack of suitable analytical techniques that track binding of individual enzymes within complex protein mixtures and the difficulty in distinguishing the contribution of productive (binding to specific glycans) versus non-productive (binding to lignin) binding of cellulases to lignocellulose, there is currently a poor ...

  1. High-throughput Saccharification Assay for Lignocellulosic Materials

    Gomez, Leonardo D; Whitehead, Caragh; Roberts, Philip; McQueen-Mason, Simon J

    2011-01-01

    Polysaccharides that make up plant lignocellulosic biomass can be broken down to produce a range of sugars that subsequently can be used in establishing a biorefinery. These raw materials would constitute a new industrial platform, which is both sustainable and carbon neutral, to replace the current dependency on fossil fuel. The recalcitrance to deconstruction observed in lignocellulosic materials is produced by several intrinsic properties of plant cell walls. Crystalline cellulose is embed...

  2. Recent Developments in the Bioconversion of Lignocelluloses into Ethanol

    KOESNANDAR; IS HELIANTI; NIKNIK NURHAYATI

    2008-01-01

    Ethanol has been commercially produced using sugars derived from sugarcane and corn. Recently, research has been focused on the development of thermotolerant and ethanol-tolerant yeast or bacteria that are able to produce ethanol efficiently, as well as the development of lignocellulosic materials as the carbon sources of fermentation. Utilization of lignocellulosic materials as fermentation substrate is promising since they are available in large amounts, renewable and relatively cheap. A li...

  3. Improving enzymatic conversion of lignocellulose to platform sugars

    Várnai, Anikó

    2012-01-01

    Increasing demand and uncertain availability of fossil fuels urge us to find alternative resources available in large quantities especially for the petrol-based transportation sector. Lignocellulosic biomass, available worldwide in plant cell walls, is a promising alternative feedstock. It can be depolymerised to sugar monomers, which provide potential raw material for sugar platform-based production of fuels and chemicals. However, the enzymatic saccharification of lignocellulose to platform...

  4. Processing Lignocellulosic Biomass into Ethanol - Implications of High Solid Loadings

    Palmqvist, Benny

    2014-01-01

    Fuel ethanol from lignocellulosic biomass has the potential to provide a sustainable replacement for traditional oil-based fuels. This dissertation assesses the processing of three different lignocellulosic materials spruce, wheat straw and giant reed at industrially relevant solid loadings. The work is divided into two main parts. The first part deals with the degradation of biomass to sugars, focusing on the complex rheological behavior of biomass slurries and the connection to mixing d...

  5. The role of pretreatment in improving the enzymatic hydrolysis of lignocellulosic materials.

    Sun, Shaoni; Sun, Shaolong; Cao, Xuefei; Sun, Runcang

    2016-01-01

    Lignocellulosic materials are among the most promising alternative energy resources that can be utilized to produce cellulosic ethanol. However, the physical and chemical structure of lignocellulosic materials forms strong native recalcitrance and results in relatively low yield of ethanol from raw lignocellulosic materials. An appropriate pretreatment method is required to overcome this recalcitrance. For decades various pretreatment processes have been developed to improve the digestibility of lignocellulosic biomass. Each pretreatment process has a different specificity on altering the physical and chemical structure of lignocellulosic materials. In this paper, the chemical structure of lignocellulosic biomass and factors likely affect the digestibility of lignocellulosic materials are discussed, and then an overview about the most important pretreatment processes available are provided. In particular, the combined pretreatment strategies are reviewed for improving the enzymatic hydrolysis of lignocellulose and realizing the comprehensive utilization of lignocellulosic materials. PMID:26321216

  6. Antioxidant and cryoprotective effects of Amur sturgeon skin gelatin hydrolysate in unwashed fish mince.

    Nikoo, Mehdi; Benjakul, Soottawat; Xu, Xueming

    2015-08-15

    Antioxidant and cryoprotective effects of Amur sturgeon skin gelatin hydrolysates prepared using different commercial proteases in unwashed fish mince were investigated. Gelatin hydrolysates prepared using either Alcalase or Flavourzyme, were effective in preventing lipid oxidation as evidenced by the lower thiobarbituric acid-reactive substances formation. Gelatin hydrolysates were able to retard protein oxidation as indicated by the retarded protein carbonyl formation and lower loss in sulfhydryl content. In the presence of gelatin hydrolysates, unwashed mince had higher transition temperature of myosin and higher enthalpy of myosin and actin as determined by differential scanning calorimetry. Based on low field proton nuclear magnetic resonance analysis, gelatin hydrolysates prevented the displacement of water molecules between the different compartments, thus stabilizing the water associated with myofibrils in unwashed mince induced by repeated freeze-thawing. Oligopeptides in gelatin hydrolysates more likely contributed to the cryoprotective effect. Thus, gelatin hydrolysate could act as both antioxidant and cryoprotectant in unwashed fish mince. PMID:25794753

  7. Cellulase-lignin interactions in the enzymatic hydrolysis of lignocellulose

    Rahikainen, J.

    2013-11-01

    Today, the production of transportation fuels and chemicals is heavily dependent on fossil carbon sources, such as oil and natural gas. Their limited availability and the environmental concerns arising from their use have driven the search for renewable alternatives. Lignocellulosic plant biomass is the most abundant, but currently underutilised, renewable carbon-rich resource for fuel and chemical production. Enzymatic degradation of structural polysaccharides in lignocellulose produces soluble carbohydrates that serve as ideal precursors for the production of a vast amount of different chemical compounds. The difficulty in full exploitation of lignocellulose for fuel and chemical production lies in the complex and recalcitrant structure of the raw material. Lignocellulose is mainly composed of structural polysaccharides, cellulose and hemicellulose, but also of lignin, which is an aromatic polymer. Enzymatic degradation of cellulose and hemicellulose is restricted by several substrate- and enzyme-related factors, among which lignin is considered as one of the most problematic issues. Lignin restricts the action of hydrolytic enzymes and enzyme binding onto lignin has been identified as a major inhibitory mechanism preventing efficient hydrolysis of lignocellulosic feedstocks. In this thesis, the interactions between cellulase enzymes and lignin-rich compounds were studied in detail and the findings reported in this work have the potential to help in controlling the harmful cellulase-lignin interactions, and thus improve the biochemical processing route from lignocellulose to fuels and chemicals.

  8. Spent nuclear fuel storage

    When a country becomes self-sufficient in part of the nuclear cycle, as production of fuel that will be used in nuclear power plants for energy generation, it is necessary to pay attention for the best method of storing the spent fuel. Temporary storage of spent nuclear fuel is a necessary practice and is applied nowadays all over the world, so much in countries that have not been defined their plan for a definitive repository, as well for those that already put in practice such storage form. There are two main aspects that involve the spent fuels: one regarding the spent nuclear fuel storage intended to reprocessing and the other in which the spent fuel will be sent for final deposition when the definitive place is defined, correctly located, appropriately characterized as to several technical aspects, and licentiate. This last aspect can involve decades of studies because of the technical and normative definitions at a given country. In Brazil, the interest is linked with the storage of spent fuels that will not be reprocessed. This work analyses possible types of storage, the international panorama and a proposal for future construction of a spent nuclear fuel temporary storage place in the country. (author)

  9. The spent fuel fate

    The spent fuel is not a waste. It can be upgrade by a reprocessing which extracts all products able to produce energy. The today situation is presented and economically analyzed and future alternatives are discussed. (A.L.B.)

  10. Spent fuel workshop'2002

    This document gathers the transparencies of the presentations given at the 2002 spent fuel workshop: Session 1 - Research Projects: Overview on the IN CAN PROCESSES European project (M. Cowper), Overview on the SPENT FUEL STABILITY European project (C. Poinssot), Overview on the French R and D project on spent fuel long term evolution, PRECCI (C. Poinssot); Session 2 - Spent Fuel Oxidation: Oxidation of uranium dioxide single crystals (F. Garrido), Experimental results on SF oxidation and new modeling approach (L. Desgranges), LWR spent fuel oxidation - effects of burn-up and humidity (B. Hanson), An approach to modeling CANDU fuel oxidation under dry storage conditions (P. Taylor); Session 3 - Spent Fuel Dissolution Experiments: Overview on high burnup spent fuel dissolution studies at FZK/INE (A. Loida), Results on the influence of hydrogen on spent fuel leaching (K. Spahiu), Leaching of spent UO2 fuel under inert and reducing conditions (Y. Albinsson), Fuel corrosion investigation by electrochemical techniques (D. Wegen), A reanalysis of LWR spent fuel flow through dissolution tests (B. Hanson), U-bearing secondary phases formed during fuel corrosion (R. Finch), The near-field chemical conditions and spent fuel leaching (D. Cui), The release of radionuclides from spent fuel in bentonite block (S.S. Kim), Trace actinide behavior in altered spent fuel (E. Buck, B. Hanson); Session 4 - Radiolysis Issues: The effect of radiolysis on UO2 dissolution determined from electrochemical experiments with 238Pu doped UO2 M. Stroess-Gascoyne (F. King, J.S. Betteridge, F. Garisto), doped UO2 studies (V. Rondinella), Preliminary results of static and dynamic dissolution tests with α doped UO2 in Boom clay conditions (K. Lemmens), Studies of the behavior of UO2 / water interfaces under He2+ beam (C. Corbel), Alpha and gamma radiolysis effects on UO2 alteration in water (C. Jegou), Behavior of Pu-doped pellets in brines (M. Kelm), On the potential catalytic behavior of UO2(s): experimental approach and preliminary results on uranium oxide - water interface (J. Devoy), Preliminary results on studies on radiolysis effects on dissolution of UO2 (E. Ekeroth, M. Jonnson); Session 5 - Modeling of the Spent Fuel Dissolution: tUO2 dissolution and the effect of radiolysis (T. Lundstrom), Prediction of the effect of radiolysis (F. King), Experimental determination and chemical modeling of radiolytic processes at the spent fuel / water interface (E. Cera, J. Bruno, T. Eriksen, M. Grive, L. Duro); Session 6 - Influence of the Potential Evolution prior to the Water Access on IRF: Potential occurrence of α self-irradiation enhanced-diffusion (H.J. Matzke, T. Petit), Are grain boundaries a stable microstructure? (Y. Guerin), Modeling RN instant release fractions from spent nuclear fuel under repository conditions (C.Poinssot, L. Johnson, P. Lovera). (J.S.)

  11. Effect of moisture on pretreatment efficiency for anaerobic digestion of lignocellulosic substrates.

    Peces, M; Astals, S; Mata-Alvarez, J

    2015-12-01

    The present study evaluates the effect of moisture in low-temperature and ultrasound pretreatment on lignocellulosic substrates anaerobic biodegradability, where brewer's spent grain was used as model substrate. Besides moisture content, low-temperature pretreatment was also evaluated in terms of temperature (60-80C) and exposure time (12-72 h). Likewise, ultrasonication was also evaluated in terms of specific energy (1000-50,000 kJ kg TS(-1)). In addition, the effect of substrate particle size reduction by milling pretreatment was also considered. The results clearly demonstrated that substrate moisture (total solid concentration) is a significant parameter for pretreatment performance, although it has been rarely considered in pretreatment optimisation. Specifically, moisture optimisation increased the methane yield of brewer's spent grain by 6% for low-temperature pretreatment (60C), and by 14% for ultrasound pretreatment (1000 kJ kg TS(-1)) towards the control (without pretreatment). In both pretreatments, the experimental optimum total solid concentration was 100 gTS kg(-1). Thus, lowering substrate moisture, a strategy suggested attaining energetic pretreatment feasibility, needs to be analysed as another pretreatment variable since it might have limited correlation. Finally, a preliminary energetic balance of the pretreatments under study showed that the extra methane production could not cover the energetic pretreatment expenses. PMID:26316102

  12. Spent fuel management

    The production of nuclear electricity results in the generation of spent fuel that requires safe, secure and efficient management. Appropriate management of the resulting spent fuel is a key issue for the steady and sustainable growth of nuclear energy. Currently about 10,000 tonnes heavy metal (HM) of spent fuel are unloaded every year from nuclear power reactors worldwide, of which 8,500 t HM need to be stored (after accounting for reprocessed fuel). This is the largest continuous source of civil radioactive material generated, and needs to be managed appropriately. Member States have referred to storage periods of 100 years and even beyond, and as storage quantities and durations extend, new challenges arise in the institutional as well as in the technical area. The IAEA gives high priority to safe and effective spent fuel management. As an example of continuing efforts, the 2003 International Conference on Storage of Spent Fuel from Power Reactors gathered 125 participants from 35 member states to exchange information on this important subject. With its large number of Member States, the IAEA is well-positioned to gather and share information useful in addressing Member State priorities. IAEA activities on this topic include plans to produce technical documents as resources for a range of priority topics: spent fuel performance assessment and research, burnup credit applications, cask maintenance, cask loading optimization, long term storage requirements including records maintenance, economics, spent fuel treatment, remote technology, and influence of fuel design on spent fuel storage. In addition to broader topics, the IAEA supports coordinated research projects and technical cooperation projects focused on specific needs

  13. Spent fuel storage chamber

    In a dry spent nuclear fuel storage chamber, an atmosphere in a closed loop comprising storage cell/heated air collecting chamber/cooling air circulation path is filled with gases having a high thermal radiation absorbing performance. Heat released from the spent fuels heats a cylindrical vessel, gases in contact with the peripheral surface thereof and metal blocks constituting the storage cell. Since the gases having highly heat absorbing performance are filled, they are heated by absorbing radiation heat of the spent fuels, to improve the heat dissipation efficiency of the spent fuels. Accordingly, even if the heat generation amount of the spent fuels is great, the temperature elevation can be suppressed since the heat dissipation efficiency of the spent fuels is great due to radiation absorption. In addition, a phenomenon that the temperature of the cylindrical vessel is raised can be suppressed. As a result, fuels or mixed oxide fuels of a high burnup degree having greater heat generation amount compared with usual fuels can be stored safely and economically. (N.H.)

  14. Allopurinol-mediated lignocellulose-derived microbial inhibitor tolerance by Clostridium beijerinckii during acetone-butanol-ethanol (ABE) fermentation.

    Ujor, Victor; Agu, Chidozie Victor; Gopalan, Venkat; Ezeji, Thaddeus Chukwuemeka

    2015-04-01

    In addition to glucans, xylans, and arabinans, lignocellulosic biomass hydrolysates contain significant levels of nonsugar components that are toxic to the microbes that are typically used to convert biomass to biofuels and chemicals. To enhance the tolerance of acetone-butanol-ethanol (ABE)-generating Clostridium beijerinckii NCIMB 8052 to these lignocellulose-derived microbial inhibitory compounds (LDMICs; e.g., furfural), we have been examining different metabolic perturbation strategies to increase the cellular reductant pools and thereby facilitate detoxification of LDMICs. As part of these efforts, we evaluated the effect of allopurinol, an inhibitor of NAD(P)H-generating xanthine dehydrogenase (XDH), on C. beijerinckii grown in furfural-supplemented medium and found that it unexpectedly increased the rate of detoxification of furfural by 1.4-fold and promoted growth, butanol, and ABE production by 1.2-, 2.5-, and 2-fold, respectively. Since NAD(P)H/NAD(P)(+) levels in C. beijerinckii were largely unchanged upon allopurinol treatment, we postulated and validated a possible basis in DNA repair to account for the solventogenic gains with allopurinol. Following the observation that supplementation of allopurinol in the C. beijerinckii growth media mitigates the toxic effects of nalidixic acid, a DNA-damaging antibiotic, we found that allopurinol elicited 2.4- and 6.7-fold increase in the messenger RNA (mRNA) levels of xanthine and hypoxanthine phosphoribosyltransferases, key purine-salvage enzymes. Consistent with this finding, addition of inosine (a precursor of hypoxanthine) and xanthine led to 1.4- and 1.7-fold increase in butanol production in furfural-challenged cultures of C. beijerinckii. Taken together, our results provide a purine salvage-based rationale for the unanticipated effect of allopurinol in improving furfural tolerance of the ABE-fermenting C. beijerinckii. PMID:25690312

  15. Identification of candidate genes for yeast engineering to improve bioethanol production in very high gravity and lignocellulosic biomass industrial fermentations

    Pereira Francisco B

    2011-12-01

    Full Text Available Abstract Background The optimization of industrial bioethanol production will depend on the rational design and manipulation of industrial strains to improve their robustness against the many stress factors affecting their performance during very high gravity (VHG or lignocellulosic fermentations. In this study, a set of Saccharomyces cerevisiae genes found, through genome-wide screenings, to confer resistance to the simultaneous presence of different relevant stresses were identified as required for maximal fermentation performance under industrial conditions. Results Chemogenomics data were used to identify eight genes whose expression confers simultaneous resistance to high concentrations of glucose, acetic acid and ethanol, chemical stresses relevant for VHG fermentations; and eleven genes conferring simultaneous resistance to stresses relevant during lignocellulosic fermentations. These eleven genes were identified based on two different sets: one with five genes granting simultaneous resistance to ethanol, acetic acid and furfural, and the other with six genes providing simultaneous resistance to ethanol, acetic acid and vanillin. The expression of Bud31 and Hpr1 was found to lead to the increase of both ethanol yield and fermentation rate, while Pho85, Vrp1 and Ygl024w expression is required for maximal ethanol production in VHG fermentations. Five genes, Erg2, Prs3, Rav1, Rpb4 and Vma8, were found to contribute to the maintenance of cell viability in wheat straw hydrolysate and/or the maximal fermentation rate of this substrate. Conclusions The identified genes stand as preferential targets for genetic engineering manipulation in order to generate more robust industrial strains, able to cope with the most significant fermentation stresses and, thus, to increase ethanol production rate and final ethanol titers.

  16. Application of a new xylanase activity from Bacillus amyloliquefaciens XR44A in brewer's spent grain saccharification

    Amore, Antonella; Parameswaran, Binod; Kumar, Ramesh MR; Birolo, Leila; Vinciguerra, Roberto; Marcolongo, Loredana; Ionata, Elena; La Cara, Francesco; Pandey, Ashok; Faraco, Vincenza

    2014-01-01

    Background Cellulases and xylanases are the key enzymes involved in the conversion of lignocelluloses into fermentable sugars. Western Ghat region (India) has been recognized as an active hot spot for the isolation of new microorganisms. The aim of this work was to isolate new microorganisms producing cellulases and xylanases to be applied in brewer's spent grain saccharification. Results 93 microorganisms were isolated from Western Ghat and screened for the production of cellulase and xylana...

  17. Use of spent substrate after Pleurotus pulmonarius cultivation for the treatment of chlorothalonil containing wastewater.

    Jurez, Rosa A Crdova; Dorry, Lilliam L Gordillo; Bello-Mendoza, Ricardo; Snchez, Jos E

    2011-03-01

    Lignocellulosic materials are used as substrate for the cultivation of the edible mushroom Pleurotus pulmonarius. After two or three flushes of mushrooms, the spent substrate is discarded although it still has an important enzymatic activity that can be used for several purposes. In this study, we sought to determine the technical feasibility of using spent substrate from P. pulmonarius to degrade chlorothalonil. Reaction mixture was prepared with 6 ml of pesticide aqueous solution (2 mg active ingredient/l) and 3 ml of enzymatic extract obtained from spent P. pulmonarius substrate. The enzymatic reaction (27 C, pH 7.4) was conducted for 1 h with sampling at 15 min intervals. The effect of storage time and temperature (freezing or refrigerating) of spent substrate and enzymatic extract, respectively, on the activity over chlorothalonil was determined. Freshly obtained spent substrate extract was able to reduce 100% of the initial concentration of chlorothalonil (2 mg/l) after 45 min of reaction. Storage time had a negative effect on the stability of the enzymatic activity: with spent substrate stored for a week, chlorothalonil concentration was reduced in 49.5% after 1 h reaction and with substrate stored for two and three weeks, the degradation efficiency decreased to 9.15% and 0%, respectively. Cooling and freezing the spent substrate extract also had a negative effect on chlorothalonil degradation. PMID:21078538

  18. Hyperthermophilic endoglucanase for in planta lignocellulose conversion

    Klose Holger

    2012-08-01

    Full Text Available Abstract Background The enzymatic conversion of lignocellulosic plant biomass into fermentable sugars is a crucial step in the sustainable and environmentally friendly production of biofuels. However, a major drawback of enzymes from mesophilic sources is their suboptimal activity under established pretreatment conditions, e.g. high temperatures, extreme pH values and high salt concentrations. Enzymes from extremophiles are better adapted to these conditions and could be produced by heterologous expression in microbes, or even directly in the plant biomass. Results Here we show that a cellulase gene (sso1354 isolated from the hyperthermophilic archaeon Sulfolobus solfataricus can be expressed in plants, and that the recombinant enzyme is biologically active and exhibits the same properties as the wild type form. Since the enzyme is inactive under normal plant growth conditions, this potentially allows its expression in plants without negative effects on growth and development, and subsequent heat-inducible activation. Furthermore we demonstrate that the recombinant enzyme acts in high concentrations of ionic liquids and can therefore degrade α-cellulose or even complex cell wall preparations under those pretreatment conditions. Conclusion The hyperthermophilic endoglucanase SSO1354 with its unique features is an excellent tool for advanced biomass conversion. Here we demonstrate its expression in planta and the possibility for post harvest activation. Moreover the enzyme is suitable for combined pretreatment and hydrolysis applications.

  19. Hyperthermophilic endoglucanase for in planta lignocellulose conversion

    2012-01-01

    Background The enzymatic conversion of lignocellulosic plant biomass into fermentable sugars is a crucial step in the sustainable and environmentally friendly production of biofuels. However, a major drawback of enzymes from mesophilic sources is their suboptimal activity under established pretreatment conditions, e.g. high temperatures, extreme pH values and high salt concentrations. Enzymes from extremophiles are better adapted to these conditions and could be produced by heterologous expression in microbes, or even directly in the plant biomass. Results Here we show that a cellulase gene (sso1354) isolated from the hyperthermophilic archaeon Sulfolobus solfataricus can be expressed in plants, and that the recombinant enzyme is biologically active and exhibits the same properties as the wild type form. Since the enzyme is inactive under normal plant growth conditions, this potentially allows its expression in plants without negative effects on growth and development, and subsequent heat-inducible activation. Furthermore we demonstrate that the recombinant enzyme acts in high concentrations of ionic liquids and can therefore degrade α-cellulose or even complex cell wall preparations under those pretreatment conditions. Conclusion The hyperthermophilic endoglucanase SSO1354 with its unique features is an excellent tool for advanced biomass conversion. Here we demonstrate its expression in planta and the possibility for post harvest activation. Moreover the enzyme is suitable for combined pretreatment and hydrolysis applications. PMID:22928996

  20. Use of Protein Hydrolysates in Industrial Starter Culture Fermentations

    Ummadi, Madhavi (Soni); Curic-Bawden, Mirjana

    Lactic acid bacteria (LAB) have been used as starter cultures for fermenting foods long before the importance of microorganisms were recognized. The most important group of LAB are the lactococci, lactobacilli, streptococci, and pediococci. Additionally, bifidobacteria have been included as a probiotic, providing added value to the product. Since the genera involved are so diverse, the nutritional requirements (energy, carbon and nitrogen sources) differ significantly between and within species. Designing an optimum fermentation medium for production of active and vigorous LAB starter cultures and probiotics requires selecting the right raw ingredients, especially protein hydrolysates that can provide adequate nutrients for growth and viability. This chapter attempts to describe the application of various commercial protein hydrolysates used for production of dairy and meat starter cultures, with special emphasis on meeting the nitrogen requirements of industrially important LAB species.

  1. Enzymatic hydrolysis of spent coffee ground.

    Jooste, T; Garca-Aparicio, M P; Brienzo, M; van Zyl, W H; Grgens, J F

    2013-04-01

    Spent coffee ground (SCG) is the main residue generated during the production of instant coffee by thermal water extraction from roasted coffee beans. This waste is composed mainly of polysaccharides such as cellulose and galactomannans that are not solubilised during the extraction process, thus remaining as unextractable, insoluble solids. In this context, the application of an enzyme cocktail (mannanase, endoglucanase, exoglucanase, xylanase and pectinase) with more than one component that acts synergistically with each other is regarded as a promising strategy to solubilise/hydrolyse remaining solids, either to increase the soluble solids yield of instant coffee or for use as raw material in the production of bioethanol and food additives (mannitol). Wild fungi were isolated from both SCG and coffee beans and screened for enzyme production. The enzymes produced from the selected wild fungi and recombinant fungi were then evaluated for enzymatic hydrolysis of SCG, in comparison to commercial enzyme preparations. Out of the enzymes evaluated on SCG, the application of mannanase enzymes gave better yields than when only cellulase or xylanase was utilised for hydrolysis. The recombinant mannanase (Man1) provided the highest increments in soluble solids yield (17 %), even when compared with commercial preparations at the same protein concentration (0.5 mg/g SCG). The combination of Man1 with other enzyme activities revealed an additive effect on the hydrolysis yield, but not synergistic interaction, suggesting that the highest soluble solid yields was mainly due to the hydrolysis action of mannanase. PMID:23436225

  2. Selection of lactic acid bacteria able to ferment inulin hydrolysates

    Octavian BASTON; Oana Emilia CONSTANTIN

    2012-01-01

    Eight homofermentative lactic acid bacteria isolates were tested for lactic acid production using chicory and Jerusalem artichoke hydrolysate as substrate. The pH, lactic acid yield and productivity were used to select the best homolactic bacteria for lactic acid production. The selected strains produced lactic acid at maximum yield after 24 hours of fermentation and the productivity was greater at 24 hours of fermentation. From all studied strains, Lb1 and Lb2 showed the best results regardi...

  3. Simulation of the continuous fermentation of manioc hydrolysate

    Bonomi, A. (Promon Engenharia S.A., Sao Paulo, Brazil); Aboutboul, H.; Schmidell, W.

    1981-01-01

    The simulation of the continuous fermentation of manioc hydrolysate utilizing a yeast strain of Saccharomyces cerevisiae isolated from the commercial pressed yeast largely employed in Brazilian distilleries is described. The model used in the simulation is derived from batch experimental runs. In order to assess the economical competitiveness of the continuous fermentation, some additional concepts, such as cell recycle, and two fermentors connected in series with and without feed division of fresh substrate, are analyzed and compared.

  4. In vitro antithrombotic activities of peanut protein hydrolysates.

    Zhang, Shao Bing

    2016-07-01

    The antithrombotic activities of peanut protein hydrolysates were investigated using a microplates assay. When peanut proteins were hydrolyzed to a limited extent by various enzymes, their thrombin inhibitory abilities were significantly enhanced. However, the resultant hydrolysates showed significantly different activities even at the same degrees of hydrolysis. The hydrolysates generated by Alcalase 2.4L displayed the best antithrombotic activities and the hydrolysis process was further optimized by response surface methodology. The antithrombotic activities were increased to 86% based on a protein concentration of 50mg/ml under the optimal conditions: pH 8.5, enzyme concentration of 5000IU/g of peanut proteins, and 2h hydrolysis time at 50°C. The Alcalase 2.4L crude hydrolysates were then fractionated successively by preparative and semi-preparative reverse-phase high-performance liquid chromatography (RP-HPLC). The peptide fraction collected inhibited thrombin-catalyzed coagulation of fibrinogen completely at a concentration of 0.4mg/ml, with an antithrombotic activity close to that of heparin at quite a low concentration (0.2mg/ml). This peptide fraction was further analyzed by online reverse-phase ultra-performance liquid chromatography (RP-UPLC) coupled to matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS), and three new peptides were identified as Ser-Trp-Ala-Gln-Leu, Gly-Asn-His-Glu-Ala-Gly-Glu and Cys-Phe-Asn-Glu-Tyr-Glu, respectively. This research provided an effective way to produce antithrombotic peptides from peanut proteins, and also helped to elucidate the structure-function relationships of peanut peptides. PMID:26920259

  5. Lignocellulosic Biomass Pretreatment: A Key to Its Successful Bioconversion to Fuel Ethanol

    Native lignocellulosic biomass is very resistant to degradation by enzymes. Prior pretreatment is essential for efficient conversion of lignocellulosic feedstock to ethanol. In this presentation, various pretreatment options such as dilute acid, alkali, alkaline peroxide, wet oxidation, steam expl...

  6. Bioflavour production from orange peel hydrolysate using immobilized Saccharomyces cerevisiae.

    Lalou, Sofia; Mantzouridou, Fani; Paraskevopoulou, Adamantini; Bugarski, Branko; Levic, Steva; Nedovic, Victor

    2013-11-01

    The rising trend of bioflavour synthesis by microorganisms is hindered by the high manufacturing costs, partially attributed to the cost of the starting material. To overcome this limitation, in the present study, dilute-acid hydrolysate of orange peel was employed as a low-cost, rich in fermentable sugars substrate for the production of flavour-active compounds by Saccharomyces cerevisiae. With this purpose, the use of immobilized cell technology to protect cells against the various inhibitory compounds present in the hydrolysate was evaluated with regard to yeast viability, carbon and nitrogen consumption and cell ability to produce flavour active compounds. For cell immobilization the encapsulation in Ca alginate beads was used. The results were compared with those obtained using free-cell system. Based on the data obtained immobilized cells showed better growth performance and increased ability for de novo synthesis of volatile esters of "fruity" aroma (phenylethyl acetate, ethyl hexanoate, octanoate, decanoate and dodecanoate) than those of free cells. The potential for in situ production of new formulations containing flavour-active compounds derive from yeast cells and also from essential oil of orange peel (limonene, ?-terpineol) was demonstrated by the fact that bioflavour mixture was found to accumulate within the beads. Furthermore, the ability of the immobilized yeast to perform efficiently repeated batch fermentations of orange peel hydrolysate for bioflavour production was successfully maintained after six consecutive cycles of a total period of 240 h. PMID:23995224

  7. Antioxidant activity of whey protein hydrolysates in milk beverage system.

    Mann, Bimlesh; Kumari, Anuradha; Kumar, Rajesh; Sharma, Rajan; Prajapati, Kishore; Mahboob, Shaik; Athira, S

    2015-06-01

    The aim of the present study was to evaluate the antioxidant activity of flavoured milk enriched with antioxidative whey protein hydrolysates (WPHs) by radical scavenging method. Whey protein concentrate (WPC) was hydrolyzed by using three commercial proteases; flavouzyme, alcalase and corolase PP and these WPHs were analyzed for degree of hydrolysis and antioxidant activity. The antioxidant activities of these WPHs were evaluated using ABTS method. Trolox equivalent antioxidant activity of all the hydrolysates i.e. flavourzyme (0.81 ± 0.04), alcalase (1.16 ± 0.05) and corolase (1.42 ± 0.12) was higher than the WPC (0.19 ± 0.01). Among these, whey protein hydrolysates prepared using corolase showed maximum antioxidant activity. Total 15 β-lactoglobulin, 1 α-lactoalbumin, and 6 β-casein derived peptide fragments were identified in the WPHs by LC-MS/MS. Due to their size and characteristic amino acid composition, all the identified peptides may contribute for the antioxidant activity. The strawberry and chocolate flavoured milk was supplemented with WPC and WPHs and 2 % addition has shown increase in antioxidant activity upto 42 %. The result suggests that WPH could be used as natural biofunctional ingredients in enhancing antioxidant properties of food products. PMID:26028704

  8. Elucidating the role of ferrous ion cocatalyst in enhancing dilute acid pretreatment of lignocellulosic biomass

    Wei Hui

    2011-11-01

    Full Text Available Abstract Background Recently developed iron cocatalyst enhancement of dilute acid pretreatment of biomass is a promising approach for enhancing sugar release from recalcitrant lignocellulosic biomass. However, very little is known about the underlying mechanisms of this enhancement. In the current study, our aim was to identify several essential factors that contribute to ferrous ion-enhanced efficiency during dilute acid pretreatment of biomass and to initiate the investigation of the mechanisms that result in this enhancement. Results During dilute acid and ferrous ion cocatalyst pretreatments, we observed concomitant increases in solubilized sugars in the hydrolysate and reducing sugars in the (insoluble biomass residues. We also observed enhancements in sugar release during subsequent enzymatic saccharification of iron cocatalyst-pretreated biomass. Fourier transform Raman spectroscopy showed that major peaks representing the C-O-C and C-H bonds in cellulose are significantly attenuated by iron cocatalyst pretreatment. Imaging using Prussian blue staining indicated that Fe2+ ions associate with both cellulose/xylan and lignin in untreated as well as dilute acid/Fe2+ ion-pretreated corn stover samples. Analyses by scanning electron microscopy and transmission electron microscopy revealed structural details of biomass after dilute acid/Fe2+ ion pretreatment, in which delamination and fibrillation of the cell wall were observed. Conclusions By using this multimodal approach, we have revealed that (1 acid-ferrous ion-assisted pretreatment increases solubilization and enzymatic digestion of both cellulose and xylan to monomers and (2 this pretreatment likely targets multiple chemistries in plant cell wall polymer networks, including those represented by the C-O-C and C-H bonds in cellulose.

  9. Advanced anaerobic bioconversion of lignocellulosic waste for the melissa life support system

    Lissens, G.; Verstraete, W.; Albrecht, T.; Brunner, G.; Creuly, C.; Dussap, G.; Kube, J.; Maerkl, H.; Lasseur, C.

    The feasibility of nearly-complete conversion of lignocellulosic waste (70% food crops, 20% faecal matter and 10% green algae) into biogas was investigated in the context of the MELiSSA loop (Micro-Ecological Life Support System Alternative). The treatment comprised a series of processes, i.e. a mesophilic laboratory scale CSTR (continuously stirred tank reactor), an upflow biofilm reactor, a fiber liquefaction reactor employing the rumen bacterium Fibrobacter succinogenes and a hydrothermolysis system in near-critical water. By the one-stage CSTR, a biogas yield of 75% with a specific biogas production of 0.37 l biogas g-1 VSS (volatile suspended solids) added at a RT (hydraulic retention time) of 20-25 d was obtained. Biogas yields could not be increased considerably at higher RT, indicating the depletion of readily available substrate after 25 d. The solids present in the CSTR-effluent were subsequently treated in two ways. Hydrothermal treatment (T ˜ 310-350C, p ˜ 240 bar) resulted in effective carbon liquefaction (50-60% without and 83% with carbon dioxide saturation) and complete sanitation of the residue. Application of the cellulolytic Fibrobacter succinogenes converted remaining cellulose contained in the CSTR-effluent into acetate and propionate mainly. Subsequent anaerobic digestion of the hydrothermolysis and the Fibrobacter hydrolysates allowed conversion of 48-60% and 30%, respectively. Thus, the total process yielded biogas corresponding with conversions up to 90% of the original organic matter. It appears that particularly mesophilic digestion in conjunction with hydrothermolysis offers interesting features for (nearly) the MELiSSA system. The described additional technologies show that complete and hygienic carbon and energy recovery from human waste within MELiSSA is technically feasible, provided that the extra energy needed for the thermal treatment is guaranteed.

  10. Destroying lignocellulosic matters for enhancing methane production from excess sludge.

    Hao, Xiaodi; Hu, Yuansheng; Cao, Daqi

    2016-03-01

    A lot of lignocellulosic matters are usually present in excess sludge, which are hardly degraded in anaerobic digestion (AD) and thus remains mostly in digested sludge. This is a reason why the conversion rate of sludge organics into energy (CH4) is often low. Obviously, the hydrolysis of AD cannot destruct the structure of lignocellulosic matters. Structural destruction of lignocellulosic matters has to be performed in AD. In this study, pretreatments with the same principles as cell disintegration of sludge were applied to destruct lignocellulosic matters so that these materials could be converted to CH4 via AD. Acid, alkali, thermal treatment and ultrasonic were used in the experiments to observe the destructed/degraded efficiency of lignocellulosic matters. Thermal treatment was found to be the most effective pretreatment. Under optimized conditions (T = 150°C and t = 30  min), pretreated sludge had a degraded rate of 52.6% in AD, due to easy destruction and/or degradation of hemicelluloses and celluloses in pretreatment. The sludge pretreated by thermal treatment could enhance the CH4 yield (mL CH4 g(-1) VSS) by 53.6% compared to raw sludge. Economically, the thermal treatment can balance the input energy with the produced energy (steam and electricity). PMID:26215289

  11. Thermoset-cross-linked lignocellulose: a moldable plant biomass.

    Karumuri, Sriharsha; Hiziroglu, Salim; Kalkan, A Kaan

    2015-04-01

    The present work demonstrates a high biomass content (i.e., up to 90% by weight) and moldable material by controlled covalent cross-linking of lignocellulosic particles by a thermoset through epoxide-hydroxyl reactions. As an example for lignocellulosic biomass, Eastern redcedar was employed. Using scanning fluorescence microscopy and vibrational spectroscopy, macroscopic to molecular scale interactions of the thermoset with the lignocellulose have been revealed. Impregnation of the polymer resin into the biomass cellular network by capillary action as well as applied pressure results in a self-organizing structure in the form of thermoset microrods in a matrix of lignocellulose. We also infer permeation of the thermoset into the cell walls from the reaction of epoxides with the hydroxyls of the lignin. Compression tests reveal, at 30% thermoset content, thermoset-cross-linked lignocellulose has superior mechanical properties over a commercial wood plastic composite while comparable stiffness and strength to bulk epoxy and wood, respectively. The failure mechanism is understood to be crack propagation along the particle-thermoset interface and/or interparticle thermoset network. PMID:25734539

  12. Bioethanol from lignocellulosics: Status and perspectives in Canada.

    Mabee, W E; Saddler, J N

    2010-07-01

    Canada has invested significantly in the development of a domestic bioethanol industry, and it is expected that bioethanol from lignocellulosics will become more desirable to the industry as it expands. Development of the Canadian industry to date is described in this paper, as are examples of domestic research programs focused on both bioconversion and thermochemical conversion to generate biofuels from lignocellulosic biomass. The availability of lignocellulosic residues from agricultural and forestry operations, and the potential biofuel production associated with these residues, is described. The policy tools used to develop the domestic bioethanol industry are explored. A residue-based process could greatly extend the potential of the bioethanol industry in Canada. It is estimated that bioethanol production from residual lignocellulosic feedstocks could provide up to 50% of Canada's 2006 transportation fuel demand, given ideal conversion and full access to these feedstocks. Utilizing lignocellulosic biomass will extend the geographic range of the bioethanol industry, and increase the stability and security of this sector by reducing the impact of localized disruptions in supply. Use of disturbance crops could add 9% to this figure, but not in a sustainable fashion. If pursued aggressively, energy crops ultimately could contribute bioethanol at a volume double that of Canada's gasoline consumption in 2006. This would move Canada towards greater transportation fuel independence and a larger role in the export of bioethanol to the global market. PMID:20006494

  13. Antioxidative, DPP-IV and ACE inhibiting peptides from fish protein hydrolysed with intestinal proteases

    Falkenberg, Susan Skanderup; Stagsted, Jan; Nielsen, Henrik Hauch

    secondary marine products. The approach in this study is to hydrolyse skin and belly flap tissue from Salmon with the use of mammalian digestive proteases from pancreas and intestinal mucosa and test hydrolysates for antioxidative capacity, intestinal DPP-IV and angiotensin converting enzyme (ACE...... amino groups, antioxidative capacity by ABTS (2,2-azinobis(3-ethylbenzothiazoline-6-sulfonicacid)), DPP-IV and ACE inhibiting activity. Degree of hydrolysis (DH) of hydrolysates was approximately 13% and 10% for belly flap and skin respectively. No clear difference was observed in DH between pancreatin...... and pancreatin + mucosa hydrolysates. No DH was obtained for tissues hydrolysed with only intestinal mucosa extract. Preliminary results showed antioxidant activity and intestinal DPP-IV and ACE inhibiting activity in 10 kDa fraction from both belly flap and skin hydrolysates but with a higher...

  14. Evaluation of the biomass potential for the production of lignocellulosic bioethanol from various agricultural residues in Austria and Worldwide

    Kahr, Heike; Steindl, Daniel; Wimberger, Julia; Schürz, Daniel; Jäger, Alexander

    2013-04-01

    Due to the fact that the resources of fossil fuels are steadily decreasing, researchers have been trying to find alternatives over the past few years. As bioethanol of the first generation is based on potential food, its production has become an increasingly controversial topic. Therefore the focus of research currently is on the production of bioethanol of the second generation, which is made from cellulosic and lignocellulosic materials. However, for the production of bioethanol of the second generation the fibres have to be pre-treated. In this work the mass balances of various agricultural residues available in Austria were generated and examined in lab scale experiments for their bioethanol potential. The residues were pretreatment by means of state of the art technology (steam explosion), enzymatically hydrolysed and fermented with yeast to produce ethanol. Special attention was paid the mass balance of the overall process. Due to the pretreatment the proportion of cellulose increases with the duration of the pre-treatment, whereby the amount of hemicellulose decreases greatly. However, the total losses were increasing with the duration of the pre-treatment, and the losses largely consist of hemicellulose. The ethanol yield varied depending on the cellulose content of the substrates. So rye straw 200 °C 20 min reaches an ethanol yield of 169 kg/t, by far the largest yield. As result on the basis of the annual straw yield in Austria, approximately 210 000 t of bioethanol (266 million litres) could be produced from the straw of wheat (Triticum vulgare), rye (Secale cereale), oat (Avena sativa) and corn (Zea mays) as well as elephant grass (Miscanthus sinensis) using appropriate pre-treatment. So the greenhouse gas emissions produced by burning fossil fuels could be reduced significantly. About 1.8 million tons of motor gasoline are consumed in Austria every year. The needed quantity for a transition to E10 biofuels could thus be easily provided by bioethanol from straw. We also evaluated the production of world's most important grains (wheat, corn, rice, sugar cain) and we calculated the worldwide production of the relevant lignocellulosic residues. On the basis of our labs scale experiments on bioethanol production, the possible lignocellulosic bioethanol production word wide was determined.

  15. Isolation and Characterization of a Nitrile-Hydrolysing Bacterium Isoptericola variabilis RGT01

    Kaur, Gurdeep; Soni, Pankaj; Tewari, Rupinder; Sharma, Rohit

    2014-01-01

    A nitrile-hydrolysing bacterium, identified as Isoptericola variabilis RGT01, was isolated from industrial effluent through enrichment culture technique using acrylonitrile as the carbon source. Whole cells of this microorganism exhibited a broad range of nitrile-hydrolysing activity as they hydrolysed five aliphatic nitriles (acetonitrile, acrylonitrile, propionitrile, butyronitrile and valeronitrile), two aromatic nitriles (benzonitrile and m-Tolunitrile) and two arylacetonitriles (4-Methox...

  16. Spent fuel pyroprocessing demonstration

    A major element of the shutdown of the U.S. liquid metal reactor development program is managing the sodium-bonded spent metallic fuel from the Experimental Breeder Reactor-II to meet U.S. environmental laws. Argonne National Laboratory has refurbished and equipped an existing hot cell facility for treating the spent fuel by a high-temperature electrochemical process commonly called pyroprocessing. Four products will be produced for storage and disposal. Two high-level waste forms will be produced and qualified for disposal of the fission and activation products. Uranium and transuranium alloys will be produced for storage pending a decision by the U.S. Department of Energy on the fate of its plutonium and enriched uranium. Together these activities will demonstrate a unique electrochemical treatment technology for spent nuclear fuel. This technology potentially has significant economic and technical advantages over either conventional reprocessing or direct disposal as a high-level waste option. (author)

  17. Spent fuel pyroprocessing demonstration

    A major element of the shutdown of the US liquid metal reactor development program is managing the sodium-bonded spent metallic fuel from the Experimental Breeder Reactor-II to meet US environmental laws. Argonne National Laboratory has refurbished and equipped an existing hot cell facility for treating the spent fuel by a high-temperature electrochemical process commonly called pyroprocessing. Four products will be produced for storage and disposal. Two high-level waste forms will be produced and qualified for disposal of the fission and activation products. Uranium and transuranium alloys will be produced for storage pending a decision by the US Department of Energy on the fate of its plutonium and enriched uranium. Together these activities will demonstrate a unique electrochemical treatment technology for spent nuclear fuel. This technology potentially has significant economic and technical advantages over either conventional reprocessing or direct disposal as a high-level waste option

  18. Spent Fuel in Chile

    The government has made a complete and serious study of many different aspects and possible road maps for nuclear electric power with strong emphasis on safety and energy independence. In the study, the chapter of SFM has not been a relevant issue at this early stage due to the fact that it has been left for later implementation stage. This paper deals with the options Chile might consider in managing its Spent Fuel taking into account foreign experience and factors related to safety, economics, public acceptance and possible novel approaches in spent fuel treatment. The country’s distinctiveness and past experience in this area taking into account that Chile has two research reactors which will have an influence in the design of the Spent Fuel option. (author)

  19. Spent fuel consolidation system

    The spent fuel consolidation system provides method and apparatus for remotely vertically and horizontally compacting an array of spent fuel rods while the fuel rods remain submerged in a coolant. The invention comprises a row ordering section for rearranging the configuration of the fuel rods, horizontal consolidation section for horizontally compacting several rows of fuel rods, and a vertical consolidation section for vertically compacting several rows of horizontally compacted fuel rods. The system is capable of compacting the fuel rods from a given fuel assembly to about one half of the volume originally occupied by such fuel rods in the fuel assembly thereby providing greater storage capacity for a given volume of spent fuel storage

  20. TRIGA spent fuel storage

    Storage of spent fuel elements is a step preliminary to final radioactive waste disposal operation. The spent fuel issue will have a common solution for both spent fuel from Cernavoda NPP and research TRIGA reactors currently operated in Romania. For the case of TRIGA reactor spent fuel this will be an alternative solution to the now functioning alternative of 'on site' storing solution adopted so far at INR Pitesti. For the time being the short term storage requirements for TRIGA spent fuel are adequately fulfilled by the pool of a multizonal reactor, the construction of which was definitively stopped. On the other hand the HEU - LEU conversion of the 14 MW TRIGA reactor which will be completed till May 2006, will pose not spent fuel problems as the TRIGA HEU fuel (612 elements) will be transferred in US (not later than May 2009). Consequently, the needs for intermediate storage will be associated only with the LEU spent fuel from TRIGA LEU-SSR and TRIGA LEU-ACPR reactors. In the latter case the maximum number of elements will be 167. For the stationary 14 MW (SSR) reactor but the amount of fuel elements to be stored on a intermediate term will be a function of service span of this reactor as well of the degree of request. Totally, some 1,750 SSR-LEU fuel elements will require intermediate storage. There is a preliminary agreement with 'NUCLEARELECTRICA -S.A.' Company regarding LEU TRIGA spent fuel storage at the intermediate storage facility for spent fuel of Cernavoda NPP.. A safety investigation is underway to determine the impact of LEU spent fuel upon the dry environment containing spent CANDU fuel. To fulfil the requirements imposed by CANDU storage technology the LEU spent fuel will be correspondingly conditioned. Then adequate containers will be used for transportation of fuel to Cernavoda's storage cell. Subcriticality condition in the storage cell loaded with LEU was checked by calculating the multiplication factor for an infinite lattice. The calculation method is based on a model according to which every TRIGA-LEU fuel element from a batch of 15 elements are cut into two equal pieces and encapsulated in stainless steel cans. The 30 encapsulated pieces are then introduced inside a capsule - a cylindrical container of CANDU fuel element cluster sizes. The empty space between fuel elements will be filled with borosilicate glass granules. Computations were carried out for burnup values of 40% and 61.5% of initial 235 U as well for fresh fuel. Dry and wet environment storage conditions were also considered. The results indicate that in the presence of borosilicate glass TRIGA-LEU fuel element fulfils the subcriticality condition irrespective of burnup value. Intermediate storage possibilities using both expertise and technological opportunities available at INR Pitesti are also considered

  1. Exploring the potentialities of using lignocellulosic fibres derived from three food by-products as constituents of biocomposites for food packaging

    Berthet, Marie-Alix; Angellier-Coussy, Hélène; Machado, Diogo; Hilliou, Loïc; Staebler, Andreas; de Vicente, Antonio; Gontard, Nathalie

    2015-01-01

    Lignocellulosic fibres obtained by dry grinding of three different solid agro-residues, i.e. wheat straw, brewing spent grains and olive mills, were compared regarding their potential use as fillers in poly(3-hydroxybutyrate-co-valerate) (PHBV) for food packaging applications. Differences found in their composition might have influenced their grinding ability, as observed with the difference of sizes, i.e. 109 μm, 148 μm and 46 μm, respectively. Thereafter, composites structure was characteri...

  2. Pretreatments employed in lignocellulosic materials for bioethanol production: an overview

    Danay Carrillo-Nieves

    2014-01-01

    Full Text Available Lignocellulosic materials are raw materials with high cellulose content and they constitute the most abun- dant sources of biomass on planet. They are attractive for their low cost and high availability in diverse climates and places for the bioethanol production, however, the main impediment for its use is the appro- priate selection from the technological and economic point of view of the stages of pretreatments and hydrolysis, that allow the breaking down of the lignocellulosic matrix to obtain the necessary substrates in the processes of fermentation. Pretreatment is an essential step in the enzymatic hydrolysis of biomass and subsequent production of bioethanol, which have been divided in three groups for its study in: physi- cal-chemical, hydrothermal and biological. The aim of this paper is to analyze the potential of several pre- treatment methods for bioethanol production from lignocellulosic materials.

  3. PRETREATMENT TECHNOLOGIES IN BIOETHANOL PRODUCTION FROM LIGNOCELLULOSIC BIOMASS

    Vanja Janušić

    2008-06-01

    Full Text Available Bioethanol is today most commonly produced from corn grain and sugar cane. It is expected that there will be limits to the supply of these raw materials in the near future. Therefore, lignocellulosic biomass, namely agricultural and forest waste, is seen as an attractive feedstock for future supplies of ethanol.Lignocellulosic biomass consists of lignin, hemicellulose and cellulose. Indeed, complexicity of the lignocellulosic biomass structure causes a pretreatment to be applied prior to cellulose and hemicellulose hydrolysis into fermentable sugars. Pretreatment technologies can be physical (mechanical comminution, pyrolysis, physico-chemical (steam explosion, ammonia fiber explosion, CO2 explosion, chemical(ozonolysis, acid hydrolysis, alkaline hydrolysis, oxidative delignification, organosolvent process and biological ones.

  4. Protein Hydrolysates from Agricultural CropsBioactivity and Potential for Functional Food Development

    Yvonne C. O'Callaghan

    2013-02-01

    Full Text Available There has been an unprecedented demand for inexpensive plant-derived protein hydrolysates in recent years, owing to their potential nutritional applications. This review examines existing evidence regarding protein hydrolysates from agricultural crops such as wheat, soy, rapeseed, sunflower and barley. The bioactivity of these protein hydrolysates, including antioxidant and anti-inflammatory capabilities are discussed. In addition to evidence regarding their potential to enhance human nutrition, the effect of the hydrolysates on the techno-functional properties of foods will be reviewed.

  5. Spent fuel reprocessing options

    The objective of this publication is to provide an update on the latest developments in nuclear reprocessing technologies in the light of new developments on the global nuclear scene. The background information on spent fuel reprocessing is provided in Section One. Substantial global growth of nuclear electricity generation is expected to occur during this century, in response to environmental issues and to assure the sustainability of the electrical energy supply in both industrial and less-developed countries. This growth carries with it an increasing responsibility to ensure that nuclear fuel cycle technologies are used only for peaceful purposes. In Section Two, an overview of the options for spent fuel reprocessing and their level of development are provided. A number of options exist for the treatment of spent fuel. Some, including those that avoid separation of a pure plutonium stream, are at an advanced level of technological maturity. These could be deployed in the next generation of industrial-scale reprocessing plants, while others (such as dry methods) are at a pilot scale, laboratory scale or conceptual stage of development. In Section Three, research and development in support of advanced reprocessing options is described. Next-generation spent fuel reprocessing plants are likely to be based on aqueous extraction processes that can be designed to a country specific set of spent fuel partitioning criteria for recycling of fissile materials to advanced light water reactors or fast spectrum reactors. The physical design of these plants must incorporate effective means for materials accountancy, safeguards and physical protection. Section four deals with issues and challenges related to spent fuel reprocessing. The spent fuel reprocessing options assessment of economics, proliferation resistance, and environmental impact are discussed. The importance of public acceptance for a reprocessing strategy is discussed. A review of modelling tools to support the development of advanced nuclear fuel cycles is also given. As a conclusion, spent fuel reprocessing options have evolved significantly since the start of nuclear energy application. There is a large body of industrial experience in fuel cycle technologies complemented by research and development programs in several countries

  6. Spent fuel store room

    The storage area for fuel elements consists of a container reception shaft with cans for spent elements, pits for these cans and closed spaces for their storage. Along the front wall of these spaces runs a rectangular transfer channel connected to each area via a hydraulically sealed inlet channel. The design of the storage area allows to continuously store and remove from storage spent fuel elements while repair and maintenance can take place of any of the storage areas. (J.B.). 4 figs

  7. Continuous co-production of ethanol and xylitol from rice straw hydrolysate in a membrane bioreactor.

    Zahed, Omid; Jouzani, Gholamreza Salehi; Abbasalizadeh, Saeed; Khodaiyan, Faramarz; Tabatabaei, Meisam

    2016-05-01

    The present study was set to develop a robust and economic biorefinery process for continuous co-production of ethanol and xylitol from rice straw in a membrane bioreactor. Acid pretreatment, enzymatic hydrolysis, detoxification, yeast strains selection, single and co-culture batch fermentation, and finally continuous co-fermentation were optimized. The combination of diluted acid pretreatment (3.5 %) and enzymatic conversion (1:10 enzyme (63 floating-point unit (FPU)/mL)/biomass ratio) resulted in the maximum sugar yield (81 % conversion). By concentrating the hydrolysates, sugars level increased by threefold while that of furfural reduced by 50 % (0.56 to 0.28 g/L). Combined application of active carbon and resin led to complete removal of furfural, hydroxyl methyl furfural, and acetic acid. The strains Saccharomyces cerevisiae NCIM 3090 with 66.4 g/L ethanol production and Candida tropicalis NCIM 3119 with 9.9 g/L xylitol production were selected. The maximum concentrations of ethanol and xylitol in the single cultures were recorded at 31.5 g/L (0.42 g/g yield) and 26.5 g/L (0.58 g/g yield), respectively. In the batch co-culture system, the ethanol and xylitol productions were 33.4 g/L (0.44 g/g yield) and 25.1 g/L (0.55 g/g yield), respectively. The maximum ethanol and xylitol volumetric productivity values in the batch co-culture system were 65 and 58 % after 25 and 60 h, but were improved in the continuous co-culture mode and reached 80 % (55 g/L) and 68 % (31 g/L) at the dilution rate of 0.03 L per hour, respectively. Hence, the continuous co-production strategy developed in this study could be recommended for producing value-added products from this hugely generated lignocellulosic waste. PMID:26354791

  8. Integration of Lignocellulosic Biomass into Renewable Energy Generation Concepts

    KUSCH Sigrid

    2009-08-01

    Full Text Available In all European countries various lignocellulosic biomasses such as agricultural residues (straw, strawcontaining dung or fractions from municipal solid waste are available in large amounts, but currently hardly any of thispotential is being used for energy generation. This paper reviews the different options for including lignocellulosicbiomass into renewable energy generation schemes. Not all wastes are suitable to be treated by principally availabletechniques such as anaerobic digestion, ethanol production or thermal valorisation. The present paper gives an overviewof utilisation options for lignocellulosic biomass to either produce biofuels or to integrate such biomass into anaerobicdigestion. Biorefinery concepts are discussed as well.

  9. Production of Bioethanol From Lignocellulosic Biomass Using Thermophilic Anaerobic Bacteria

    Georgieva, Tania I.

    2006-01-01

    residual lignocellulose (wastes) created from forest industries or from agricultural food crops (wheat straw, corn stover, rice straw). The lignocellulose contains lignin, which binds carbohydrate polymers (cellulose and hemicellulose) forming together a rather resistant structure. In this regards, a pre......Bioethanol (ethanol produced from biomass) as a motor fuel is an attractive renewable fully sustainable energy sources as a means of lowering dependence on fossil fuels and air pollution towards greenhouse gasses, particularly CO2. Bioethanol, unlike gasoline, is an oxygenated fuel, which burns...

  10. Evaluation of four ionic liquids for pretreatment of lignocellulosic biomass.

    Gräsvik, John; Winestrand, Sandra; Normark, Monica; Jönsson, Leif; Mikkola, Jyri-Pekka

    2014-01-01

    BACKGROUND: Lignocellulosic biomass is highly recalcitrant and various pretreatment techniques are needed to facilitate its effective enzymatic hydrolysis to produce sugars for further conversion to bio-based chemicals. Ionic liquids (ILs) are of interest in pretreatment because of their potential to dissolve lignocellulosic materials including crystalline cellulose. RESULTS: Four imidazolium-based ionic liquids (ILs) ([C=C2C1im][MeCO2], [C4C1im][MeCO2], [C4C1im][Cl], and [C4C1im][HSO4]) well...

  11. Use of nuclear wastes in utilization of lignocellulosic biomass

    The practices of high energy irradiation of biomass to increase its utility are reviewed. Sugar yield, digestibility to acid and enzymatic hydrolysis, and changes in chemical and physical properties of lignocellulosic materials upon irradiation are investigated. Gamma irradiation at the dose of 50 Mrad or greater extensively degraded and solubilized sugarcane bagasse in water, but direct production of fermentable sugars from biomass by gamma irradiation was difficult because of decomposition of the sugars. Possible use of nuclear wastes (in the form of caesium-137) in utilization of lignocellulosic biomass are discussed. (author)

  12. Microbial Activity on the Degradation of Lignocellulosic Polysaccharides

    Zakaria Ahmed

    2001-01-01

    Full Text Available In present world there is an increase in demand for organic waste disposal to minimize pollution and maximize resource recovery. Several workers from various parts of the world have reported successful conversion of waste materials to useful compost. Lignocellulose comprises three different polymer types: lignin, hemicellulose and cellulose. Bioconversion of lignocellulosic material through microbial enzyme to produce fermentable sugars has been given serious consideration and continuous research and development activities has been carried out in laboratories around the world. This article highlights the significant research findings and reviews the state of the art in this very important area of biotechnology.

  13. Cellulase production using biomass feed stock and its application in lignocellulose saccharification for bio-ethanol production

    Sukumaran, Rajeev K.; Singhania, Reeta Rani; Mathew, Gincy Marina; Pandey, Ashok [Biotechnology Division, National Institute for Interdisciplinary Science and Technology, CSIR, Trivandrum-695 019 (India)

    2009-02-15

    A major constraint in the enzymatic saccharification of biomass for ethanol production is the cost of cellulase enzymes. Production cost of cellulases may be brought down by multifaceted approaches which include the use of cheap lignocellulosic substrates for fermentation production of the enzyme, and the use of cost efficient fermentation strategies like solid state fermentation (SSF). In the present study, cellulolytic enzymes for biomass hydrolysis were produced using solid state fermentation on wheat bran as substrate. Crude cellulase and a relatively glucose tolerant BGL were produced using fungi Trichoderma reesei RUT C30 and Aspergillus niger MTCC 7956, respectively. Saccharification of three different feed stock, i.e. sugar cane bagasse, rice straw and water hyacinth biomass was studied using the enzymes. Saccharification was performed with 50 FPU of cellulase and 10 U of {beta}-glucosidase per gram of pretreated biomass. Highest yield of reducing sugars (26.3 g/L) was obtained from rice straw followed by sugar cane bagasse (17.79 g/L). The enzymatic hydrolysate of rice straw was used as substrate for ethanol production by Saccharomyces cerevisiae. The yield of ethanol was 0.093 g per gram of pretreated rice straw. (author)

  14. Improved Cellulose and Organic-Solvents based Lignocellulosic Fractionation Pre-treatment of Organic Waste for Bioethanol Production

    Valeriy Bekmuradov

    2014-06-01

    Full Text Available This study investigates the performance of the Cellulose and Organic-Solvents based Lignocellulosic Fractionation (COSLIF method for the pretreatment of Source-Separated Organic (SSO waste. An improvement on the standard method of COSLIF pre-treatment was developed based on lower enzyme loading and using an ethanol washing instead of acetone. It was demonstrated that a much higher glucose yield (90% after 72 hours was possible with this improvement, as compared to the original method, which yielded 70% in the same time frame. Evaluation of the enzymatic hydrolysate obtained from the modified COSLIF pretreatment was further examined by anaerobic fermentation with Zymomonas mobilis 8b strain. At 48 hours, ethanol concentration reached to 140 g/L, which is equivalent to 0.48 g of ethanol produced per gram of SSO biomass. This study demonstrated that the modified COSLIF pretreatment provides a substantial improvement over the standard method in terms of enzyme savings, glucose formation, and ethanol production.

  15. Improved lignocellulose conversion to biofuels with thermophilic bacteria and thermostable enzymes.

    Bhalla, Aditya; Bansal, Namita; Kumar, Sudhir; Bischoff, Kenneth M; Sani, Rajesh K

    2013-01-01

    Second-generation feedstock, especially nonfood lignocellulosic biomass is a potential source for biofuel production. Cost-intensive physical, chemical, biological pretreatment operations and slow enzymatic hydrolysis make the overall process of lignocellulosic conversion into biofuels less economical than available fossil fuels. Lignocellulose conversions carried out at ? 50 C have several limitations. Therefore, this review focuses on the importance of thermophilic bacteria and thermostable enzymes to overcome the limitations of existing lignocellulosic biomass conversion processes. The influence of high temperatures on various existing lignocellulose conversion processes and those that are under development, including separate hydrolysis and fermentation, simultaneous saccharification and fermentation, and extremophilic consolidated bioprocess are also discussed. PMID:23246299

  16. Production, characterization and application of activated carbon from brewers spent grain lignin

    Mussatto, Solange I.; Fernandes, Marcela; Rocha, George J. M.; rfo, Jos J. M.; Teixeira, J. A; Roberto, Ins Conceio

    2010-01-01

    Different types of activated carbon were prepared by chemical activation of brewers spent grain (BSG) lignin using H3PO4 at various acid/lignin ratios (1, 2, or 3 g/g) and carbonization temperatures (300, 450, or 600 C), according to a 22 full-factorial design. The resulting materials were characterized with regard to their surface area, pore volume, and pore size distribution, and used for detoxification of BSG hemicellulosic hydrolysate (a mixture of sugars, phenolic compounds, metallic i...

  17. Biogeochemical cycling of lignocellulosic carbon in marine and freshwater ecosystems: relative contributions of procaryotes and eucaryotes

    The relative contributions of procaryotes and eucaryotes to the degradation of the lignin and polysaccharide components of lignocellulosic detritus in two marine and two freshwater wetland ecosystems were determined. Two independent methods - physical separation of bacteria from fungi and other eucaryotes by size fractionation, and antibiotic treatments - were used to estimate procaryotic and eucaryotic contributions to the degradation of [14C-lignin]lignocelluloses and [13C-polysaccharide]lignocelluloses in samples of water and decaying plant material from each environment. Both methods yielded similar results; bacteria were the predominant degraders of lignocellulose in each of the aquatic ecosystems. These results indicate a basic difference between the microbial degradation of lignocellulosic material in terrestrial and aquatic environments. Fungi have long been considered the predominant degraders of lignocellulose in terrestrial systems; our results indicate that in aquatic systems bacteria are the predominant degraders of lignocellulose

  18. Producing Fish Protein Hydrolysates from Mackerel By-Products

    Ana Luísa De Sousa Augusto

    2014-01-01

    Portugal is one of the largest consumers of fishery products in Europe. This consumption involves a large amount of discarded raw material, such as rejected fish in selling auctions and the generation of by-products in industrial production processes. The by-products in the canning industry alone reach 40% of the raw material, while the frozen fish industries may reach 10-50% of the raw material (INE, 2013). Fish protein hydrolysates (FPH) are one of the most promising technologies for th...

  19. Lignin Production by Organosolv Fractionation of Lignocellulosic Biomass

    Huijgen, W.J.J.; De Wild, P.J.; Reith, J.H. [ECN Biomass, Coal and Environment, Petten (Netherlands)

    2010-09-15

    The contents of this presentation comprise an introduction of Lignin and lignocellulosic biomass, and Biomass pre-treatment and fractionation; outline of Organosolv fractionation (Experimental set-up, Process conditions, and Catalysts); the Production and Characterisation of Lignin, and finally the Conclusions.

  20. Effects of lactic acid bacteria contamination on lignocellulosic ethanol fermentation

    Slower fermentation rates, mixed sugar compositions, and lower sugar concentrations may make lignocellulosic fermentations more susceptible to contamination by lactic acid bacteria (LAB), which is a common and costly problem to the corn-based fuel ethanol industry. To examine the effects of LAB con...

  1. Microbial lipid based lignocellulosic biorefinery: feasibility and challenges

    Although single cell oil (SCO) has been studied for decades, lipid production from lignocellulosic biomass has only received substantial attention in recent years as biofuel research moves toward producing drop-in fuels. This review article gives an overview of the feasibility and challenges that ex...

  2. Biohydrogen Production from Lignocellulosic Biomass: Technology and Sustainability

    Anoop Singh

    2015-11-01

    Full Text Available Among the various renewable energy sources, biohydrogen is gaining a lot of traction as it has very high efficiency of conversion to usable power with less pollutant generation. The various technologies available for the production of biohydrogen from lignocellulosic biomass such as direct biophotolysis, indirect biophotolysis, photo, and dark fermentations have some drawbacks (e.g., low yield and slower production rate, etc., which limits their practical application. Among these, metabolic engineering is presently the most promising for the production of biohydrogen as it overcomes most of the limitations in other technologies. Microbial electrolysis is another recent technology that is progressing very rapidly. However, it is the dark fermentation approach, followed by photo fermentation, which seem closer to commercialization. Biohydrogen production from lignocellulosic biomass is particularly suitable for relatively small and decentralized systems and it can be considered as an important sustainable and renewable energy source. The comprehensive life cycle assessment (LCA of biohydrogen production from lignocellulosic biomass and its comparison with other biofuels can be a tool for policy decisions. In this paper, we discuss the various possible approaches for producing biohydrogen from lignocellulosic biomass which is an globally available abundant resource. The main technological challenges are discussed in detail, followed by potential solutions.

  3. Dynamic modeling and validation of a lignocellulosic enzymatic hydrolysis process

    Prunescu, Remus Mihail; Sin, Gürkan

    2013-01-01

    The enzymatic hydrolysis process is one of the key steps in second generation biofuel production. After being thermally pretreated, the lignocellulosic material is liquefied by enzymes prior to fermentation. The scope of this paper is to evaluate a dynamic model of the hydrolysis process on a...

  4. Construction Cost Sensitivity of a Lignocellulosic Ethanol Biorefinery

    Busby, David P.; Philips, Andrew L.; Herndon, Cary W., Jr.

    2008-01-01

    The technology has been developed to convert feedstock with cellulose content into ethanol. However, ethanol produced from cellulosic feedstock is the same as ethanol distilled from grain. The objective of research is to determine the price per gallon of ethanol needed so that producing lignocellulosic based ethanol become economically feasible.

  5. Lignocellulose Biomass: Constitutive Polymers. Biological Processes of Lignin Degradation

    The structure of the lignocellulosic materials and the chemical composition of their main constitutive polymers, cellulose, hemicelluloses and lignin are described. The most promising transformation processes according to the type of biomass considered: hardwood, softwood an herbaceous and the perspectives of biotechnological processes for bio pulping, bio bleaching and effluents decolorisation in the paper pulp industry are also discussed. (Author) 7 refs

  6. Process for Production of Hydrolysed Collagen from Agriculture Resources: Potential for Further Development

    Abdul Wahab Mohammad

    2014-01-01

    Full Text Available Collagen is not a uniform substance, but is rather a family of protein. It is a group of naturally occurring proteins found in animals, especially in the flesh and connective tissues of mammals. For food or nutritional purpose, collagen is broken down into gelatine which can be broken down further into hydrolysed collagen. Hydrolysed collagen is a polypeptide composite made by further hydrolysis of denatured collagen or gelatin and the molecular weights are within the range approximately 500 to 25000 Da. In hydrolysate, the molecular mass and the size of the molecules have been deliberately decreased by hydrolysis part of peptide bonds of the gelatine molecules. This will make the hydrolysed collagen dissolved in cold water and does not gel anymore but still has surface active properties. The processes involved in processing hydrolysed collagen are demineralization, extraction of collagen to gelatine, enzymatic hydrolysis to obtain hydrolysed collagen, ion exchange, filtration, evaporation, sterilization and finally drying. In previous study a large number of studies focused on the enzymatic hydrolysis of collagen or gelatine for the production of bioactive peptide. However, studies focusing on the process development of hydrolysed collagen are still limited. This study thus will briefly describe the process design, market potential, research and development work and potential future research development for the production of hydrolysed collagen from agriculture sources such as cattle bones, fish skins and fish scales.

  7. Study on Hydrolysis Conditions of Flavourzyme in Soybean Polypeptide Alcalase Hydrolysate and Soybean Polypeptide Refining Process

    Yongsheng Ma

    2014-10-01

    Full Text Available Soybean protein Alcalase hydrolysate was further hydrolyzed by adopting Flavourzyme as hydrolytic enzyme. The optimal hydrolysis conditions of Flavourzyme was that pH was 7.0 at temperature 50°C and E/S(ratio of enzyme and substrate was 20LAPU/g. Bitterness value was reduced to 2 after Flavourzyme hydrolysis reaction in optimal hydrolysis conditions. The change of molecular weight distribution range from Alcalase hydrolysate to Flavourzyme hydrolysate was not obvious. DH (Degree of hydrolysis of soybean protein hydrolysate was increased to 24.2% which was improved 3.5% than Alcalase hydrolysate. Protein recovery proportion was increased to 73.2% which was improved 0.8% than Alcalase hydrolysate. Soybean polypeptide Flavourzyme hydrolysate was decolorized with activated carbon which optimal dosage was 1.2% solution amount (w/w. Anion/cation exchange process was used in the desalination processing of soybean polypeptide. Ratio of anion resin and cation resin was 2:3(V/V. The volume of hydrolysate processed was 5 times as the volume of anion resin. Ash content of soybean peptide solution reduced to 2.11% (dry basis, salinity decreased by 86% after desalination processing.

  8. Dipeptidyl peptidase IV inhibitory and antioxidative properties of milk protein-derived dipeptides and hydrolysates.

    Nongonierma, Alice B; FitzGerald, Richard J

    2013-01-01

    Selected synthetic dipeptides and milk protein hydrolysates were evaluated for their dipeptidyl peptidase IV (DPP-IV) inhibitory properties, and their superoxide (SO) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activities. DPP-IV inhibition was seen with eight out of the twelve dipeptides and 5 of the twelve hydrolysates studied. Trp-Val inhibited DPP-IV, however, inhibition was not observed with the reverse peptide Val-Trp. The most potent hydrolysate inhibitors were generated from casein (CasH2) and lactoferrin (LFH1). Two Trp containing dipeptides, Trp-Val and Val-Trp, and three lactoferrin hydrolysates scavenged DPPH. The dipeptides had higher SO EC(50) values compared to the milk protein hydrolysates (arising from three lactoferrin and one whey protein hydrolysates). Higher molecular mass fractions of the milk protein hydrolysates were associated with the SO scavenging activity. Trp-Val and one lactoferrin hydrolysate (LFH1) were multifunctional displaying both DPP-IV inhibitory and antioxidant (SO and DPPH scavenging) activities. These compounds may have potential as dietary ingredients in the management of type 2 diabetes by virtue of their ability to scavenge reactive oxygen species and to extend the half-life of incretin molecules. PMID:23219487

  9. Stability of Mackerel (Trachurus japonicas Hydrolysate with Iron-Binding Capacity in Simulated Gastrointestinal Fluids

    Wen-Ting Zhang

    2015-01-01

    Full Text Available The aim of this study was to investigate the stability of mackerel (Trachurus japonicas processing byproducts protein hydrolysate with iron-binding capacity in vitro simulated gastrointestinal systems. The changes in molecular weight distribution and iron-binding capacity were used for evaluating the stability of the hydrolysate in simulated gastrointestinal digestion. The molecular weight of mackerel hydrolysate with iron-binding capacity was mostly less than 1300 Da and composted mainly by tripeptides to undepeptides. The hydrolysate was stable in gastric or intestinal digestion separately for 5 h, or two-stage gastrointestinal digestion. The iron-binding capacity did not change significantly during gastrointestinal digestion. The mackerel processing byproducts hydrolysate had potential in iron fortification functional ingredients of food industry.

  10. Time well spent

    Fallesen, Peter

    2013-01-01

    different average durations of foster care because of differences in exposure to a reform. Later born cohorts spent on average 3 months longer in foster care than earlier born cohorts. Isolating exogenous variation in duration of foster care, the study finds positive effects of increased duration of foster......Individuals who spent time in foster care as children fare on average worse than non-placed peers in early adult life. Recent research on the effect of foster care placement on early adult life outcomes provides mixed evidence. Some studies suggest negative effects of foster care placement on early...... adult outcomes, others find null effects. This study shows that differences in the average duration of foster care stays explain parts of these discordant findings and then test how foster care duration shapes later life outcomes using administrative data on 7 220 children. The children experienced...

  11. Spent fuel shipping casks

    The reply includes a list specifying the spent fuel tasks that have been licensed for shipment in the FRG by the Federal Radiation Protection Office. This list of permits forms part of the 'Directory of National Competent Authorities' Approval Certificates For Package Design and Shipment of Radioactive Material, 1990 Edition', IAEA-TECDOC-552, Vienna 1990. Applications for approval of some further casks are under review. In accordance with the IAEA recommendations for the safe transport of radioactive substances, which have been fully and authentically incorporated into the German regulations for the carriage of dangerous goods, spent fuel casks licensed for shipments have to be of the type B(U). Proof of safety of type B casks under accident conditions is given by design testing within the framework of the approval and licensing procedure subject to the traffic safety regulations. (orig./HSCH)

  12. Gelatin hydrolysates from farmed Giant catfish skin using alkaline proteases and its antioxidative function of simulated gastro-intestinal digestion.

    Ketnawa, Sunantha; Martínez-Alvarez, Oscar; Benjakul, Soottawat; Rawdkuen, Saroat

    2016-02-01

    This work aims to evaluate the ability of different alkaline proteases to prepare active gelatin hydrolysates. Fish skin gelatin was hydrolysed by visceral alkaline-proteases from Giant catfish, commercial trypsin, and Izyme AL®. All antioxidant activity indices of the hydrolysates increased with increasing degree of hydrolysis (Pskin, could serve as a potential source of functional food ingredients for health promotion. PMID:26304317

  13. Encapsulating spent nuclear fuel

    A system is described for encapsulating spent nuclear fuel discharged from nuclear reactors in the form of rods or multi-rod assemblies. The rods are completely and contiguously enclosed in concrete in which metallic fibres are incorporated to increase thermal conductivity and polymers to decrease fluid permeability. This technique provides the advantage of acceptable long-term stability for storage over the conventional underwater storage method. Examples are given of suitable concrete compositions. (UK)

  14. Structural and Antihypertensive Properties of Enzymatic Hemp Seed Protein Hydrolysates

    Sunday A. Malomo

    2015-09-01

    Full Text Available The aim of this work was to produce antihypertensive protein hydrolysates through different forms of enzymatic hydrolysis (2% pepsin, 4% pepsin, 1% alcalase, 2% alcalase, 2% papain, and 2% pepsin + pancreatin of hemp seed proteins (HSP. The hemp seed protein hydrolysates (HPHs were tested for in vitro inhibitions of renin and angiotensin-converting enzyme (ACE, two of the enzymes that regulate human blood pressure. The HPHs were then administered orally (200 mg/kg body weight to spontaneously hypertensive rats and systolic blood pressure (SBP-lowering effects measured over a 24 h period. Size exclusion chromatography mainly showed a 300–9560 Da peptide size range for the HPHs, while amino acid composition data had the 2% pepsin HPH with the highest cysteine content. Fluorescence spectroscopy revealed higher fluorescence intensities for the peptides when compared to the unhydrolyzed hemp seed protein. Overall, the 1% alcalase HPH was the most effective (p < 0.05 SBP-reducing agent (−32.5 ± 0.7 mmHg after 4 h, while the pepsin HPHs produced longer-lasting effects (−23.0 ± 1.4 mmHg after 24 h. We conclude that an optimized combination of the fast-acting HPH (1% alcalase with the longer-lasting HPHs (2% and 4% pepsin could provide daily effective SBP reductions.

  15. Structural and Antihypertensive Properties of Enzymatic Hemp Seed Protein Hydrolysates.

    Malomo, Sunday A; Onuh, John O; Girgih, Abraham T; Aluko, Rotimi E

    2015-09-01

    The aim of this work was to produce antihypertensive protein hydrolysates through different forms of enzymatic hydrolysis (2% pepsin, 4% pepsin, 1% alcalase, 2% alcalase, 2% papain, and 2% pepsin + pancreatin) of hemp seed proteins (HSP). The hemp seed protein hydrolysates (HPHs) were tested for in vitro inhibitions of renin and angiotensin-converting enzyme (ACE), two of the enzymes that regulate human blood pressure. The HPHs were then administered orally (200 mg/kg body weight) to spontaneously hypertensive rats and systolic blood pressure (SBP)-lowering effects measured over a 24 h period. Size exclusion chromatography mainly showed a 300-9560 Da peptide size range for the HPHs, while amino acid composition data had the 2% pepsin HPH with the highest cysteine content. Fluorescence spectroscopy revealed higher fluorescence intensities for the peptides when compared to the unhydrolyzed hemp seed protein. Overall, the 1% alcalase HPH was the most effective (p < 0.05) SBP-reducing agent (-32.5 ± 0.7 mmHg after 4 h), while the pepsin HPHs produced longer-lasting effects (-23.0 ± 1.4 mmHg after 24 h). We conclude that an optimized combination of the fast-acting HPH (1% alcalase) with the longer-lasting HPHs (2% and 4% pepsin) could provide daily effective SBP reductions. PMID:26378569

  16. Antioxidative activity of whey protein hydrolysates in a liposomal system.

    Peña-Ramos, E A; Xiong, Y L

    2001-12-01

    Whey protein isolate (WPI) with or without preheating (90 degrees C for 5 min) was hydrolyzed for 0.5 to 6 h using four pure enzymes (pepsin, papain, trypsin, and chymotrypsin) and three commercial crude proteases. After determining the degree of hydrolysis, the hydrolysates were incubated (37 degrees C, 1 h) with a liposome oxidizing system (50 mM FeCl3/0.1 mM ascorbate, pH 7.0). Lipid oxidation was measured by determining the concentrations of TBA-reactive substances (TBARS). The degree of hydrolysis of WPI ranged from 4 to 37% depending on the enzymes used and whether the substrate was heated or not. WPI hydrolysates prepared by pure enzyme treatments did not prevent TBARS formation in the oxidative model system, but WPI hydrolyzed by the commercial crude enzymes, especially protease F, exhibited antioxidant activity. The antioxidative potential of hydrolyzed WPI was not affected by the degree of hydrolysis, and it was improved by preheat treatment in only some samples. PMID:11814013

  17. Spent fuel dissolution mechanisms

    This study is a literature survey on the dissolution mechanisms of spent fuel under disposal conditions. First, the effects of radiolysis products on the oxidative dissolution mechanisms and rates of UO2 are discussed. These effects have mainly been investigated by using electrochemical methods. Then the release mechanisms of soluble radionuclides and the dissolution of the UO2 matrix including the actinides, are treated. Experimental methods have been developed for measuring the grain-boundary inventories of radionuclides. The behaviour of cesium, strontium and technetium in leaching tests shows different trends. Comparison of spent fuel leaching data strongly suggests that the release of 90Sr into the leachant can be used as a measure of the oxidation/dissolution of the fuel matrix. Approaches to the modelling UO2, dissolution are briefly discussed in the next chapter. Lastly, the use of natural material, uraninite, in the evaluation of the long-term performance of spent fuel is discussed. (orig.). (81 ref., 37 figs., 8 tabs.)

  18. Total reuse of brewers spent grain in chemical and biotechnological processes for the production of added-value compounds

    Mussatto, Solange I.; Dragone, Giuliano; Teixeira, J. A; Roberto, Ins Conceio

    2008-01-01

    Brewers spent grain was fractionated by means of three different procedures: dilute acid hydrolysis, for the hemicellulose recovery; alkaline hydrolysis, for the lignin solubilization, and enzymatic hydrolysis, for the cellulose conversion into glucose. The best hydrolysis conditions were optimized to each case. The cellulosic and hemicellulosic hydrolysates produced under these conditions were used as fermentation medium for the production of lactic acid and xylitol, respectively. The effic...

  19. Application of Complex Fluids in Lignocellulose Processing

    Carrillo Lugo, Carlos A.

    Complex fluids such as emulsions, microemulsions and foams, have been used for different applications due to the multiplicity of properties they possess. In the present work, such fluids are introduced as effective media for processing lignocellulosic biomass. A demonstration of the generic benefits of complex fluids is presented to enhance biomass impregnation, to facilitate pretreatment for fiber deconstruction and to make compatible cellulose fibrils with hydrophobic polymers during composite manufacture. An improved impregnation of woody biomass was accomplished by application of water-continuous microemulsions. Microemulsions with high water content, > 85%, were formulated and wood samples were impregnated by wicking and capillary flooding at atmospheric pressure and temperature. Formulations were designed to effectively impregnate different wood species during shorter times and to a larger extent compared to the single components of the microemulsions (water, oil or surfactant solutions). The viscosity of the microemulsions and their interactions with cell wall constituents in fibers were critical to define the extent of impregnation and solubilization. The relation between composition and formulation variables and the extent of microemulsion penetration in different woody substrates was studied. Formulation variables such as salinity content of the aqueous phase and type of surfactant were elucidated. Likewise, composition variables such as the water-to-oil ratio and surfactant concentration were investigated. These variables affected the characteristics of the microemulsion and determined their effectiveness in wood treatment. Also, the interactions between the surfactant and the substrate had an important contribution in defining microemulsion penetration in the capillary structure of wood. Microemulsions as an alternative pretreatment for the manufacture of cellulose nanofibrils (CNFs) was also studied. Microemulsions were applied to pretreat lignin-free and lignin-containing fibers obtained from various processes. Incorporation of active agents in the microemulsion facilitated fiber pretreatment before deconstruction via grinding and microfluidization. The energy consumed during the manufacture of cellulose nanofibrils was reduced by up to 55 and 32% in the case of lignin-containing and lignin-free fibers. Moreover, such pre-treatment did not affect negatively the mechanical properties of films prepared with the produced CNF. CNF was also used to enhance the stability of normal and multiple emulsions of the water-in-oil-in-water (W/O/W) type and to prevent their creaming. This was achieved by the marked increase in viscosity of the aqueous phase in the presence CNF. Finally, water-continuous emulsions were used to prepare nanocomposite fibers containing polystyrene and CNF. The morphology of composite fibers obtained after electrospinning of emulsions incorporating polystyrene and CNF was affected by parameters such the concentration of surfactant additives present in the microemulsion and the conductivity of the aqueous phase. Overall, emulsions and microemulsions are presented as a convenient platform to improve the compatibility between polymers of different hydrophilicity, to facilitate their processing and integration in composites.

  20. Decolorization of hair dye by lignocellulosic waste materials from contaminated waters

    AbelEnriqueNavarro

    2014-07-01

    Full Text Available Basic yellow 57 (BY57 was chosen as a model hair dye due to its prevalence in cosmetics wastewaters. This study proposes the use of lignocellulosic materials like spent tea leaves of peppermint (PM, chai tea (CT and chamomile (CM as raw adsorbents for the removal of BY57 from contaminated solutions. Batch adsorption experiments were carried out at room temperature to achieve the maximum adsorption capacity. Results indicate that the highest removal is achieved at pH 6 – 8, with a minimum adsorbent mass of 75 mg and in the absence of salinity, crowding agents and heavy metals. Adsorption equilibria were modeled according to the Langmuir and Freundlich isotherm theories and reported the following trend: PM>CT>CM, reaching qmax values of 105, 80, and 38 mg of dye per gram of adsorbent, respectively. Desorption experiments showed that diluted solution of HCl is able to desorb the up to 80% of the dye and recover the adsorbent to be used in consecutive cycles. Finally, the adsorbents were characterized by Scanning electron microscopy, indicating that the adsorbents have a porous and heterogeneous surface, showing pockets and protrusions that are potential adsorption sites for the dye.

  1. The effect of Pleurotus ostreatus arabinofuranosidase and its evolved variant in lignocellulosic biomasses conversion.

    Marcolongo, Loredana; Ionata, Elena; La Cara, Francesco; Amore, Antonella; Giacobbe, Simona; Pepe, Olimpia; Faraco, Vincenza

    2014-11-01

    The fungal arabinofuranosidase from Pleurotus ostreatus PoAbf recombinantly expressed in Pichia pastoris rPoAbf and its evolved variant rPoAbf F435Y/Y446F were tested for their effectiveness to enhance the enzymatic saccharification of three lignocellulosic biomasses, namely Arundo donax, corn cobs and brewer's spent grains (BSG), after chemical or chemical-physical pretreatment. All the raw materials were subjected to an alkaline pretreatment by soaking in aqueous ammonia solution whilst the biomass from A. donax was also pretreated by steam explosion. The capability of the wild-type and mutant rPoAbf to increase the fermentable sugars recovery was assessed by using these enzymes in combination with different (hemi)cellulolytic activities. These enzymatic mixtures were either entirely of commercial origin or contained the cellulase from Streptomyces sp. G12 CelStrep recombinantly expressed in Escherichia coli in substitution to the commercial counterparts. The addition of the arabinofuranosidases from P. ostreatus improved the hydrolytic efficiency of the commercial enzymatic cocktails on all the pretreated biomasses. The best results were obtained using the rPoAbf evolved variant and are represented by increases of the xylose recovery up to 56.4%. These data clearly highlight the important role of the accessory hemicellulolytic activities to optimize the xylan bioconversion yields. PMID:25046861

  2. The quality of silage of corn grain and spent P. ostreatus mushroom substrate

    Adamovi? Milan J.

    2007-01-01

    Full Text Available The chemical composition, fermentation quality, mycological and mycotoxicological analyses of silage mixture, made of ground corn grain and spent P. ostreatus mushroom substrate, were investigated in this paper. Dry matter content in high moisture ground corn, at the time of ensiling was 70%, and in the spent substrate (on the Salt Cedar wood shaving basis was 52.7%. Corn grain to spent substrate ratio in trials was: 100:0% (I, 90:10% (II, 80:20% (III and 70:30% (IV respectively. Content of the lignocellulose fractions in silage was slightly increased, and protein content was slightly decreased with the increase of spent substrate content. Contents of the VFA (volatile fatty acids in silage, pH value, and NH3-N content were for the silage of very good quality. In the spent substrate 9 mold species were found, from which the most frequent were genus Penicillium, Paecilomyces variotii, and Trichoderma harzianum. In ground corn grain silage (I presence of the yeasts was dominant (90.000/g. In combined trials (II-IV only Penicillium (P. brevicompactum and P. echinulatum mold species were found. Presence of molds and yeasts in investigated trials was within tolerated values for ensiled feedstuffs. Mycotoxin presence in silage was not determined.

  3. Spent fuel storage requirements

    Spent fuel storage requirements, as projected through the year 2000 for U.S. LWRs, were calculated using information supplied by the utilities reflecting plant status as of December 31, 1981. Projections through the year 2000 combined fuel discharge projections of the utilities with the assumed discharges of typical reactors required to meet the nuclear capacity of 165 GWe projected by the Energy Information Administration (EIA) for the year 2000. Three cases were developed and are summarized. A reference case, or maximum at-reactor (AR) capacity case, assumes that all reactor storage pools are increased to their maximum capacities as estimated by the utilities for spent fuel storage utilizing currently licensed technologies. The reference case assumes no transshipments between pools except as currently licensed by the Nuclear Regulatory Commission (NRC). This case identifies an initial requirement for 13 MTU of additional storage in 1984, and a cumulative requirement for 14,490 MTU additional storage in the year 2000. The reference case is bounded by two alternative cases. One, a current capacity case, assumes that only those pool storage capacity increases currently planned by the operating utilities will occur. The second, or maximum capacity with transshipment case, assumes maximum development of pool storage capacity as described above and also assumes no constraints on transshipment of spent fuel among pools of reactors of like type (BWR, PWR) within a given utility. In all cases, a full core discharge capability (full core reserve or FCR) is assumed to be maintained for each reactor, except that only one FCR is maintained when two reactors share a common pool. For the current AR capacity case the indicated storage requirements in the year 2000 are indicated to be 18,190 MTU; for the maximum capacity with transshipment case they are 11,320 MTU

  4. Enzymatic hydrolysis of ovomucoid and the functional properties of its hydrolysates.

    Abeyrathne, E D N S; Lee, H Y; Jo, C; Suh, J W; Ahn, D U

    2015-09-01

    Ovomucoid is well known as a "trypsin inhibitor" and is considered to be the main food allergen in egg. However, the negative functions of ovomucoid can be eliminated if the protein is cut into small peptides. The objectives of this study were to hydrolyze ovomucoid using various enzyme combinations, and compare the functional properties of the hydrolysates. Purified ovomucoid was dissolved in distilled water (20 mg/mL) and treated with 1% of pepsin, α-chymotrypsin, papain, and alcalase, singly or in combinations. Sodium sodium dodecyl sulfate-polyacrylamide (SDS-PAGE) results of the hydrolysates indicated that pepsin (OMP), alcalase (OMAl), alcalase+trypsin (OMAlTr), and alcalase+papain (OMAlPa) treatments best hydrolyzed the ovomucoid, and the 4 treatments were selected to determine their functional characteristics. Among the 4 enzyme treatments, hydrolysate from OMAlTr showed the highest iron-chelating and antioxidant activities, while OMP showed higher ACE-inhibitory activity, but lower Fe-chelating activity than the other treatments. However, no difference in the copper-chelating activity among the treatments was found. MS/MS analysis identified numerous peptides from the hydrolysates of OMAlPa and OMAlTr, and majority of the peptides produced were enzyme hydrolysates were not consistent with the number and size of peptides in the hydrolysates, but we do not have information about the quantity of each peptide present in the hydrolysates at this point. PMID:26195809

  5. Factors causing compositional changes in soy protein hydrolysates and effects on cell culture functionality.

    Gupta, Abhishek J; Gruppen, Harry; Maes, Dominick; Boots, Jan-Willem; Wierenga, Peter A

    2013-11-13

    Soy protein hydrolysates significantly enhance cell growth and recombinant protein production in cell cultures. The extent of this enhancement in cell growth and IgG production is known to vary from batch to batch. This can be due to differences in the abundance of different classes of compounds (e.g., peptide content), the quality of these compounds (e.g., glycated peptides), or the presence of specific compounds (e.g., furosine). These quantitative and qualitative differences between batches of hydrolysates result from variation in the seed composition and seed/meal processing. Although a considerable amount of literature is available that describes these factors, this knowledge has not been combined in an overview yet. The aim of this review is to identify the most dominant factors that affect hydrolysate composition and functionality. Although there is a limited influence of variation in the seed composition, the overview shows that the qualitative changes in hydrolysate composition result in the formation of minor compounds (e.g., Maillard reaction products). In pure systems, these compounds have a profound effect on the cell culture functionality. This suggests that the presence of these compounds in soy protein hydrolysates may affect hydrolysate functionality as well. This influence on the functionality can be of direct or indirect nature. For instance, some minor compounds (e.g., Maillard reaction products) are cytotoxic, whereas other compounds (e.g., phytates) suppress protein hydrolysis during hydrolysate production, resulting in altered peptide composition, and, thus, affect the functionality. PMID:24117369

  6. Characterization of structural and functional properties of fish protein hydrolysates from surimi processing by-products.

    Liu, Yongle; Li, Xianghong; Chen, Zhijun; Yu, Jian; Wang, Faxiang; Wang, Jianhui

    2014-05-15

    Structural and functional properties of fish protein hydrolysates with different degrees of hydrolysis (DH) from surimi processing by-products, prepared by Protamex and Alcalase, were evaluated. As the DH increased, the zeta potentials of the hydrolysates increased (p>0.05). The surface hydrophobicity of the hydrolysates was significantly affected by DH (p<0.05). A wide variety of peptides were obtained after hydrolysis by Protamex and Alcalase. The hydrolysate with DH 10%, prepared by Protamex, contained more large protein molecules than did the others. Hydrolysis by both enzymes increased solubility to more than 65% over a wide pH range (pH 2-10). The interfacial activities of hydrolysates decreased with increasing DH (p<0.05). The hydrolysate with DH 10%, prepared by Protamex, exhibited the best interfacial properties among all of the samples. Thermal properties were also affected by the hydrolysis. The results reveal that structures and functionalities of the hydrolysates were determined both by DH and enzyme type employed. PMID:24423557

  7. Generation, Fractionation, and Characterization of Iron-Chelating Protein Hydrolysate from Palm Kernel Cake Proteins.

    Zarei, Mohammad; Ghanbari, Rahele; Tajabadi, Naser; Abdul-Hamid, Azizah; Bakar, Fatimah Abu; Saari, Nazamid

    2016-02-01

    Palm kernel cake protein was hydrolyzed with different proteases namely papain, bromelain, subtilisin, flavourzyme, trypsin, chymotrypsin, and pepsin to generate different protein hydrolysates. Peptide content and iron-chelating activity of each hydrolysate were evaluated using O-phthaldialdehyde-based spectrophotometric method and ferrozine-based colorimetric assay, respectively. The results revealed a positive correlation between peptide contents and iron-chelating activities of the protein hydrolysates. Protein hydrolysate generated by papain exhibited the highest peptide content of 10.5 mM and highest iron-chelating activity of 64.8% compared with the other hydrolysates. Profiling of the papain-generated hydrolysate by reverse phase high performance liquid chromatography fractionation indicated a direct association between peptide content and iron-chelating activity in most of the fractions. Further fractionation using isoelectric focusing also revealed that protein hydrolysate with basic and neutral isoelectric point (pI) had the highest iron-chelating activity, although a few fractions in the acidic range also exhibited good metal chelating potential. After identification and synthesis of papain-generated peptides, GGIF and YLLLK showed among the highest iron-chelating activities of 56% and 53%, whereas their IC50 were 1.4 and 0.2 ?M, respectively. PMID:26720491

  8. Antioxidant and antimicrobial activity of lecithin free egg yolk protein preparation hydrolysates obtained with digestive enzymes

    Aleksandra Zambrowicz

    2012-12-01

    Full Text Available ABSTRACT:Several biological activities have now been associated with egg protein- derived peptides, including antihypertensive, antimicrobial, immunomodulatory, anticancer and antioxidantactivities, highlighting the importance of these biopeptides in human health, and disease prevention and treatment. Special attention has been given to peptides with antioxidant and antimicrobial activities as a new source of natural preservatives in food industry. In this study, the antioxidant properties of the egg-yolk protein by-product (YP hydrolysates were evaluated based on their radical scavenging capacity (DPPH, Fe2+chelating effect and ferric reducing power (FRAP. Furthermore, antimicrobial properties of obtained hydrolysates against Bacillus species were studied. The degrees (DHs of hydrolysis for 4h hydrolysates were: 19.1%, 13.5% and 13.0%, for pepsin, chymotrypsin and trypsin, respectively. Pepsin was the most effective in producing the free amino groups (1410.3 μmolGly/g. The RP-HPLC profiles of the protein hydrolysates showed differences in the hydrophobicity of the generated peptides.Trypsin hydrolysate obtained after 4h reaction demonstrated the strongest DPPH free radical scavenging activity (0.85 µmol Troloxeq/mg. Trypsin and chymotrypsin hydrolysates obtained after 4h reaction exhibited 4 times higher ferric reducing capacity than those treated bypepsin. The hydrolysis products obtained from YP exhibited significant chelating activity. The 4h trypsin hydrolysate exhibited weak antimicrobial activity against B. subtilis B3; B. cereus B512; B. cereus B 3p and B. laterosporum B6.

  9. Antioxidant activities of red tilapia (Oreochromis niloticus) protein hydrolysates as influenced by thermolysin and alcalase

    Daud, Nur'Aliah; Babji, Abdul Salam; Yusop, Salma Mohamad

    2013-11-01

    The hydrolysis process was performed on fish meat from Red Tilapia (Oreochromis niloticus) by enzymes thermolysin and alcalase under optimum conditions. The hydrolysis was performed from 0 - 4 hours at 37C. Hydrolysates after 2 hours incubation with thermolysin and alcalase had degree of hydrolysis of 76.29 % and 63.49 %, respectively. The freeze dried protein hydrolysate was tested for peptide content and characterized with respect to amino acid composition. The result of increased peptide content in Red Tilapia (O. Niloticus) hydrolysates obtained was directly proportional to the increase activities of different proteolytic enzymes. The result of amino acid composition showed that the sample used contained abundant Gly, Ala, Asp, Glu, Lys and Leu in residues or peptide sequences. Both enzymatic hydrolysates were tested for anti-oxidant activity with DPPH and ABTS assay. Alcalase yielded higher anti-oxidative activity than Thermolysin hydrolysates after 1 hour incubation, but both enzymes hydrolysates showed a significant decrease of anti-oxidant activity after 2 hours of incubation. Hydrolysates from Red Tilapia may contribute as a health promoting ingredient in functional foods to reduce oxidation stress caused by accumulated free radicals.

  10. Thermophysical Properties of Lignocellulose: A Cell-scale Study down to 41K

    Cheng, Zhe; Zhang, Lei; Wang, Xinwei

    2014-01-01

    Thermal energy transport is of great importance in lignocellulose pyrolysis for bio-fuels. The thermophysical properties of lignocellulose significantly affect the overall properties of bio-composites and the related thermal transport. In this work, cell-scale lignocellulose (mono-layer plant cells) is prepared to characterize their thermal properties from room temperature down to 41 K. The thermal conductivities of cell-scale lignocellulose along different directions show a little anisotropy due to the cell structure anisotropy. It is found that with temperature going down, the volumetric specific heat of the lignocellulose shows a slower decreasing trend against temperature than that of microcrystalline cellulose, and its value is always higher than that of microcrystalline cellulose. The thermal conductivity of lignocellulose decreases with temperature from 243 K to 317 K due to increasing phonon-phonon scatterings. From 41 K to 243 K, the thermal conductivity rises with temperature and its change mainly d...

  11. Particle properties of sugar maple hemicellulose hydrolysate and its influence on growth and metabolic behavior of Pichia stipitis.

    Sun, Zhijie; Shupe, Alan; Liu, Tingjun; Hu, Ruofei; Amidon, Thomas E; Liu, Shijie

    2011-01-01

    In this study the influence of the insoluble solids in nano-filtrated sugar maple hemicellulosic hydrolysate on the metabolic behavior of Pichia stiptis was investigated. The particle properties of hemicellulosic hydrolysate were analyzed. Phosphoric acid and ammonium (PA) were applied to remove the particles. The metabolic behavior and growth property of P. stipitis in particle--removed hydrolysate was measured. Results demonstrated that the average particle size and zeta potential of the untreated hydrolysate were 2266.9±78.2 nm and -6.09±0.49 mV. Xylose consumption and ethanol production rate were significantly decreased when particle content is greater than 1.63 g/L. Because the majority of particles (34 g/L) were removed from hydrolysates by phosphoric acid and ammonium treatment, the fermentability of the hydrolysate was significantly improved. These results indicated particles play an important role in hydrolysate inhibition effect. PMID:20855196

  12. Characterization of the Immunogenicity and Allergenicity of Two Cow's Milk Hydrolysates – A Study in Brown Norway Rats

    Bøgh, Katrine Lindholm; Barkholt, Vibeke; Madsen, Charlotte Bernhard

    2015-01-01

    immunogenicity. Only antibodies from rats sensitized to intact BLG with adjuvant were able to bind the hydrolysates, and the whey‐based hydrolysate only showed immunogenicity when dosed with adjuvant. This study showed that hydrolysates can be evaluated by an i.p. animal model, but that the choice of in vitro......Hypoallergenic infant formulas based on hydrolysed milk proteins are used in the diet for cow's milk allergic infants. For a preclinical evaluation of the immunogenicity and allergenicity of new protein ingredients for such hypoallergenic infant formulas as well as for the investigation of which...... characteristics of hydrolysates that contribute to allergenicity, in vivo models are valuable tools. In this study, we examine the immunogenicity and allergenicity of two hydrolysates in a Brown Norway (BN) rat model, using i.p. dosing, which allows for the use of small quantities. Intact BLG, hydrolysed BLG and...

  13. Flow-through biological conversion of lignocellulosic biomass

    Herring, Christopher D.; Liu, Chaogang; Bardsley, John

    2014-07-01

    The present invention is directed to a process for biologically converting carbohydrates from lignocellulosic biomass comprising the steps of: suspending lignocellulosic biomass in a flow-through reactor, passing a reaction solution into the reactor, wherein the solution is absorbed into the biomass substrate and at least a portion of the solution migrates through said biomass substrate to a liquid reservoir, recirculating the reaction solution in the liquid reservoir at least once to be absorbed into and migrate through the biomass substrate again. The biological converting of the may involve hydrolyzing cellulose, hemicellulose, or a combination thereof to form oligosaccharides, monomelic sugars, or a combination thereof; fermenting oligosaccharides, monomelic sugars, or a combination thereof to produce ethanol, or a combination thereof. The process can further comprise removing the reaction solution and processing the solution to separate the ethanol produced from non-fermented solids.

  14. Wheat straw: An inefficient substrate for rapid natural lignocellulosic composting.

    Zhang, Lili; Jia, Yangyang; Zhang, Xiaomei; Feng, Xihong; Wu, Jinjuan; Wang, Lushan; Chen, Guanjun

    2016-06-01

    Composting is a promising method for the management of agricultural wastes. However, results for wheat straw composts with different carbon-to-nitrogen ratios revealed that wheat straw was only partly degraded after composting for 25days, with hemicellulose and cellulose content decreasing by 14% and 33%, respectively. No significant changes in community structure were found after composting according to 454-pyrosequencing. Bacterial communities were represented by Proteobacteria and Bacteroidetes throughout the composting process, including relatively high abundances of pathogenic microbes such as Pseudomonas and Flexibacter, suggesting that innocent treatment of the composts had not been achieved. Besides, the significant lignocellulose degrader Thermomyces was not the exclusively dominant fungus with relative abundance only accounting for 19% of fungal communities. These results indicated that comparing with maize straw, wheat straw was an inefficient substrate for rapid natural lignocellulose-based composting, which might be due to the recalcitrance of wheat straw. PMID:26980627

  15. Biodegradation of lignocellulosic materials: Present status and future prospects

    The biodegradation of lignocellulosic material depends on the source and prior treatment of the substrate. As the composition of the substrate influences the mode of degradation, a resume of the structure of cell wall components is given. This shows the relationship between cellulose, hemicelluloses, lignin and the other non-carbohydrate components and how they are arranged within the wall architecture. A summary is given of the different types of enzymes which can attack lignocellulosics, some limitations on their use, and how they can be influenced by other methods of pretreatment. The role of different types of microorganisms is discussed and the paper concludes with some results from work by the authors. (author). 37 refs, 4 figs

  16. Canonical correlations between chemical and energetic characteristics of lignocellulosic wastes

    Thiago de Paula Protásio

    2012-09-01

    Full Text Available Canonical correlation analysis is a statistical multivariate procedure that allows analyzing linear correlation that may exist between two groups or sets of variables (X and Y. This paper aimed to provide canonical correlation analysis between a group comprised of lignin and total extractives contents and higher heating value (HHV with a group of elemental components (carbon, hydrogen, nitrogen and sulfur for lignocellulosic wastes. The following wastes were used: eucalyptus shavings; pine shavings; red cedar shavings; sugar cane bagasse; residual bamboo cellulose pulp; coffee husk and parchment; maize harvesting wastes; and rice husk. Only the first canonical function was significant, but it presented a low canonical R². High carbon, hydrogen and sulfur contents and low nitrogen contents seem to be related to high total extractives contents of the lignocellulosic wastes. The preliminary results found in this paper indicate that the canonical correlations were not efficient to explain the correlations between the chemical elemental components and lignin contents and higher heating values.

  17. Enhancement of glycerol production with ram horn hydrolysate by yeast

    The potential use of ram horn hydrolysate (RHH) as a supplement for enhancement of glycerol production by Saccharomyces cerevisiae was studied. For this purpose, first, RHH was produced. Ram horns were hydrolyzed by treating with acid (6 N H2SO4), and the RHH was obtained. The contents of protein, nitrogen, ash, some minerals, total sugars, total lipids and amino acids of RHH were determined. With the addition of RHH to the fermentation medium with a final concentration of 4% (optimal concentration), the glycerol value reached a maximum value of 9.4 g l-1, which is 47% higher than that of the control experiment. The addition of 4% (v/v) RHH enhanced the glycerol accumulation, reduced the residual sugar concentration and stimulated yeast growth. Adding 4% RHH had no adverse effects on the cells of S. cerevisiae. As a result, RHH was found to be suitable as a valuable supplement for glycerol production in the batch fermentation

  18. Synthesis, characterization and application of novel aminated gelatin hydrolysate

    Gelatin is biocompatible with body and does not harm the health, so it can be used as environmental friendly formaldehyde scavenger. The aminated gelatin with many amiqogen, carboxyl and amide functional group was synthesized by using diethylene triamine and gelatin hydrolysate, and then it was characterized using Fourier transform infrared spectrometer (FTIR) and gel penetrating chromatogram (GPC) testing. The results showed that the amidogen content increased to nearly double and the acylation reaction had occurred. Moreover, the prepared aminated gelatin was used to remove free formaldehyde in simulating air test. The application results indicated that when the dosage of aminated gelatin was 7.5g and reaction time was 20min, the percentage of formaldehyde removal reached 94 %. (author)

  19. Identification of bitter peptides in whey protein hydrolysate.

    Liu, Xiaowei; Jiang, Deshou; Peterson, Devin G

    2014-06-25

    Bitterness of whey protein hydrolysates (WPH) can negatively affect product quality and limit utilization in food and pharmaceutical applications. Four main bitter peptides were identified in a commercial WPH by means of sensory-guided fractionation techniques that included ultrafiltration and offline two-dimensional reverse phase chromatography. LC-TOF-MS/MS analysis revealed the amino acid sequences of the bitter peptides were YGLF, IPAVF, LLF, and YPFPGPIPN that originated from α-lactalbumin, β-lactoglobulin, serum albumin, and β-casein, respectively. Quantitative LC-MS/MS analysis reported the concentrations of YGLF, IPAVF, LLF, and YPFPGPIPN to be 0.66, 0.58, 1.33, and 2.64 g/kg powder, respectively. Taste recombination analysis of an aqueous model consisting of all four peptides was reported to explain 88% of the bitterness intensity of the 10% WPH solution. PMID:23998904

  20. System and method for conditioning a hardwood pulp liquid hydrolysate

    Waite, Darrell; Arnold, Richard; St. Pierre, James; Pendse, Hemant P.; Ceckler, William H.

    2015-06-30

    A system and method for hardwood pulp liquid hydrolysate conditioning includes a first evaporator receives a hardwood mix extract and outputting a quantity of vapor and extract. A hydrolysis unit receives the extract, hydrolyzes and outputs to a lignin separation device, which separates and recovers a quantity of lignin. A neutralization device receives extract from the lignin separation device and a neutralizing agent, producing a mixture of solid precipitate and a fifth extract. The solid precipitate is removed from the fifth extract. A second evaporator removes a quantity of acid from the fifth extract in a vapor form. This vapor may be recycled to improve total acid recovery or discarded. A desalination device receives the diluted extract, separates out some of the acid and salt and outputs a desalinated solution.

  1. Energy and Environmental Performance of Bioethanol from Different Lignocelluloses

    Gjalt Huppes; Ester van der Voet; Lin Luo

    2010-01-01

    Climate change and the wish to reduce the dependence on oil are the incentives for the development of alternative energy sources. The use of lignocellulosic biomass together with cellulosic processing technology provides opportunities to produce fuel ethanol with less competition with food and nature. Many studies on energy analysis and life cycle assessment of second-generation bioethanol have been conducted. However, due to the different methodology used and different system boundary defini...

  2. Integration of Lignocellulosic Biomass into Renewable Energy Generation Concepts

    Kusch, Sigrid; Maria V. MORAR

    2009-01-01

    In all European countries various lignocellulosic biomasses such as agricultural residues (straw, strawcontaining dung) or fractions from municipal solid waste are available in large amounts, but currently hardly any of thispotential is being used for energy generation. This paper reviews the different options for including lignocellulosicbiomass into renewable energy generation schemes. Not all wastes are suitable to be treated by principally availabletechniques such as anaerobic digestion, ...

  3. High performance maleated lignocellulose epicarp fibers for copper ion removal

    Vieira, A. P.; S. A. A. Santana; C. W. B. Bezerra; H. A. S. Silva; K. C. A. Santos; J. C. P. Melo; E. C. Silva Filho; C. Airoldi

    2014-01-01

    Natural lignocellulosic fiber epicarp extracted from the babassu coconut (Orbignya speciosa) was chemically modified through reaction with molten maleic anhydride without solvent, with incorporation of 189.34 mg g-1 of carboxylic acid groups into the biopolymer structure. The success of this reaction was also confirmed by the presence of carboxylic acid bands at 1741 and 1164 cm-1 in the infrared spectrum. Identically, the same group is observed through 13C NMR CP/MAS in the solid state, via ...

  4. EVALUATION OF DIFFERENT APPROACHES FOR THE DRYING OF LIGNOCELLULOSE RESIDUES

    Carolina Tenorio,; Roger Moya

    2012-01-01

    The main objective of this study was to evaluate three methodological approaches for the drying (air drying, solar drying, and hot-air drying) of three lignocelluloses residues in Costa Rica, namely the empty fruit bunches of oil palm (EFB), pineapple plant leaves (PL) with different treatments on this leaf, and sawdust from Gmelina arborea (GAD). The initial moisture content (MCi), the drying times, and the variation of moisture content (MC) with time were determined. A mathematical model of...

  5. STEAM EXPLOSION : PROCESS AND IMPACT ON LIGNOCELLULOSIC MATERIAL

    Jacquet, Nicolas; Vanderghem, Caroline; Danthine, Sabine; Blecker, Christophe; Paquot, Michel

    2012-01-01

    Steam explosion is a thermomechanochemical process which allows the breakdown of lignocellulosic structural components by steam heating, hydrolysis of glycosidic bonds by organic acid formed during the process and shearing forces due to the expansion of the moisture. The process is composed of two distinct stages: vapocracking and explosive decompression. Cumul effects of both phases include modification of the physical properties of the material (specific surface area, water retention capaci...

  6. Membrane separations in ionic liquid assisted processing of lignocellulosic biomass

    Abels, Christian

    2014-01-01

    2nd generation biofuels currently hold a significant market share. With increasing impact of biofuel its production routes have to be optimized in terms of CO2 emissions, competition with the food chain and utilization of the whole plant. The cluster of excellence "Tailor-made Fuels from Biomass" investigates processing of lignocellulosic biomass to next generation biofuels. Complete utilization of the raw material is achieved by initial separation of its constituents cellulose, hemicellulose...

  7. Lab-scale Technology for Biogas Production from Lignocellulose Wastes

    Lukáš Krátký; Tomáš Jirout; Jiří Nalezenec

    2012-01-01

    Currently-operating biogas plants are based on the treatment of lignocellulose biomass, which is included in materials such as agriculture and forestry wastes, municipal solid wastes, waste paper, wood and herbaceous energy crops. Lab-scale biogas technology was specially developed for evaluating the anaerobic biodegrability and the specific methane yields of solid organic substrates. This technology falls into two main categories – pretreatment equipments, and fermentation equipments. Pretre...

  8. Fungal treated lignocellulosic biomass as ruminant feed ingredient: a review.

    van Kuijk, S J A; Sonnenberg, A S M; Baars, J J P; Hendriks, W H; Cone, J W

    2015-01-01

    In ruminant nutrition, there is an increasing interest for ingredients that do not compete with human nutrition. Ruminants are specialists in digesting carbohydrates in plant cell walls; therefore lignocellulosic biomass has potential in ruminant nutrition. The presence of lignin in biomass, however, limits the effective utilization of cellulose and hemicellulose. Currently, most often chemical and/or physical treatments are used to degrade lignin. White rot fungi are selective lignin degraders and can be a potential alternative to current methods which involve potentially toxic chemicals and expensive equipment. This review provides an overview of research conducted to date on fungal pretreatment of lignocellulosic biomass for ruminant feeds. White rot fungi colonize lignocellulosic biomass, and during colonization produce enzymes, radicals and other small compounds to breakdown lignin. The mechanisms on how these fungi degrade lignin are not fully understood, but fungal strain, the origin of lignocellulose and culture conditions have a major effect on the process. Ceriporiopsis subvermispora and Pleurotus eryngii are the most effective fungi to improve the nutritional value of biomass for ruminant nutrition. However, conclusions on the effectiveness of fungal delignification are difficult to draw due to a lack of standardized culture conditions and information on fungal strains used. Methods of analysis between studies are not uniform for both chemical analysis and in vitro degradation measurements. In vivo studies are limited in number and mostly describing digestibility after mushroom production, when the fungus has degraded cellulose to derive energy for fruit body development. Optimization of fungal pretreatment is required to shorten the process of delignification and make it more selective for lignin. In this respect, future research should focus on optimization of culture conditions and gene expression to obtain a better understanding of the mechanisms involved and allow the development of superior fungal strains to degrade lignin in biomass. PMID:25447421

  9. Modeling and analysis of the enzymatic hydrolysis of lignocellulosic substrates

    Sola Saura, Alaia

    2010-01-01

    Simultaneous saccharification and fermentation (SSF) and simultaneous saccharification and cofermentation (SSCF) are two process options for production of ethanol from lignocellulosic substrates that are superior to separate hydrolysis and fermentation (SHF). The principal benefits of performing the enzymatic hydrolysis together with the fermentation, instead of in a separate step after the hydrolysis as SHF does, are the reduced end-product inhibition of the enzymatic hydrolysis, and t...

  10. Canonical correlations between chemical and energetic characteristics of lignocellulosic wastes

    Thiago de Paula Protásio; Gustavo Henrique Denzin Tonoli; Mário Guimarães Júnior; Lina Bufalino; Allan Motta Couto; Paulo Fernando Trugilho

    2012-01-01

    Canonical correlation analysis is a statistical multivariate procedure that allows analyzing linear correlation that may exist between two groups or sets of variables (X and Y). This paper aimed to provide canonical correlation analysis between a group comprised of lignin and total extractives contents and higher heating value (HHV) with a group of elemental components (carbon, hydrogen, nitrogen and sulfur) for lignocellulosic wastes. The following wastes were used: eucalyptus shavings; pine...

  11. The Comparative Life Cycle Assessment of Power Generation from Lignocellulosic Biomass

    Xinhua Shen; Raghava R. Kommalapati; Ziaul Huque

    2015-01-01

    In order to solve the energy crisis and reduce emissions of greenhouse gases (GHG), renewable energy resources are exploited for power generation. Because lignocellulosic biomass resources are abundant and renewable, various technologies are applied to using lignocellulosic biomass to derive biofuel and electricity. This paper focuses on power generation from lignocellulosic biomass and comparison of the effects of different feedstocks, transportation, and power generation technologies evalua...

  12. Effect of steam explosion pre-treatment on enzymatic saccharification of lignocellulosic material

    Meyer, Laurence; Jacquet, Nicolas; Vanderghem, Caroline; Blecker, Christophe; Paquot, Michel

    2011-01-01

    Taking into account the sharp rise in prices and the depletion of resources of petroleum, an alternative to fossil resources is needed. A probable alternative is the use of lignocellulosic raw material to produce biofuels. The first generation biofuels are highly controversial because of the use of food plant material. The aim of the second generation biofuels is to take lignocellulosic non-food plant material as raw material. Lignocellulosic biomass has a very complex structure made o...

  13. Ethylenediamine pretreatment changes cellulose allomorph and lignin structure of lignocellulose at ambient pressure

    Qin, Lei; Li, Wen-Chao; Zhu, Jia-Qing; Liang, Jing-Nan; Li, Bing-zhi; Yuan, Ying-jin

    2015-01-01

    Background Pretreatment of lignocellulosic biomass is essential to increase the cellulase accessibility for bioconversion of lignocelluloses by breaking down the biomass recalcitrance. In this work, a novel pretreatment method using ethylenediamine (EDA) was presented as a simple process to achieve high enzymatic digestibility of corn stover (CS) by heating the biomass–EDA mixture with high solid-to-liquid ratio at ambient pressure. The effect of EDA pretreatment on lignocellulose was further...

  14. Deconstruction of Lignocellulose into Soluble Sugars by Native and Designer Cellulosomes

    Moraïs, Sarah; Morag, Ely; Barak, Yoav; Goldman, Dan; Hadar, Yitzhak; Lamed, Raphael; Shoham, Yuval; Wilson, David B.; Bayer, Edward A.

    2012-01-01

    ABSTRACT Lignocellulosic biomass, the most abundant polymer on Earth, is typically composed of three major constituents: cellulose, hemicellulose, and lignin. The crystallinity of cellulose, hydrophobicity of lignin, and encapsulation of cellulose by the lignin-hemicellulose matrix are three major factors that contribute to the observed recalcitrance of lignocellulose. By means of designer cellulosome technology, we can overcome the recalcitrant properties of lignocellulosic substrates and th...

  15. Hemicellulases and auxiliary enzymes for improved conversion of lignocellulosic biomass to monosaccharides

    Hermanson Spencer

    2011-02-01

    Full Text Available Abstract Background High enzyme loading is a major economic bottleneck for the commercial processing of pretreated lignocellulosic biomass to produce fermentable sugars. Optimizing the enzyme cocktail for specific types of pretreated biomass allows for a significant reduction in enzyme loading without sacrificing hydrolysis yield. This is especially important for alkaline pretreatments such as Ammonia fiber expansion (AFEX pretreated corn stover. Hence, a diverse set of hemicellulases supplemented along with cellulases is necessary for high recovery of monosaccharides. Results The core fungal cellulases in the optimal cocktail include cellobiohydrolase I [CBH I; glycoside hydrolase (GH family 7A], cellobiohydrolase II (CBH II; GH family 6A, endoglucanase I (EG I; GH family 7B and β-glucosidase (βG; GH family 3. Hemicellulases tested along with the core cellulases include xylanases (LX1, GH family 10; LX2, GH family 10; LX3, GH family 10; LX4, GH family 11; LX5, GH family 10; LX6, GH family 10, β-xylosidase (LβX; GH family 52, α-arabinofuranosidase (LArb, GH family 51 and α-glucuronidase (LαGl, GH family 67 that were cloned, expressed and/or purified from different bacterial sources. Different combinations of these enzymes were tested using a high-throughput microplate based 24 h hydrolysis assay. Both family 10 (LX3 and family 11 (LX4 xylanases were found to most efficiently hydrolyze AFEX pretreated corn stover in a synergistic manner. The optimal mass ratio of xylanases (LX3 and LX4 to cellulases (CBH I, CBH II and EG I is 25:75. LβX (0.6 mg/g glucan is crucial to obtaining monomeric xylose (54% xylose yield, while LArb (0.6 mg/g glucan and LαGl (0.8 mg/g glucan can both further increase xylose yield by an additional 20%. Compared with Accellerase 1000, a purified cocktail of cellulases supplemented with accessory hemicellulases will not only increase both glucose and xylose yields but will also decrease the total enzyme loading needed for equivalent yields. Conclusions A diverse set of accessory hemicellulases was found necessary to enhance the synergistic action of cellulases hydrolysing AFEX pretreated corn stover. High glucose (around 80% and xylose (around 70% yields were achieved with a moderate enzyme loading (~20 mg protein/g glucan using an in-house developed cocktail compared to commercial enzymes.

  16. Cellulosic hydrolysate toxicity and tolerance mechanisms in Escherichia coli

    Gill Ryan T

    2009-10-01

    Full Text Available Abstract The sustainable production of biofuels will require the efficient utilization of lignocellulosic biomass. A key barrier involves the creation of growth-inhibitory compounds by chemical pretreatment steps, which ultimately reduce the efficiency of fermentative microbial biocatalysts. The primary toxins include organic acids, furan derivatives, and phenolic compounds. Weak acids enter the cell and dissociate, resulting in a drop in intracellular pH as well as various anion-specific effects on metabolism. Furan derivatives, dehydration products of hexose and pentose sugars, have been shown to hinder fermentative enzyme function. Phenolic compounds, formed from lignin, can disrupt membranes and are hypothesized to interfere with the function of intracellular hydrophobic targets. This review covers mechanisms of toxicity and tolerance for these compounds with a specific focus on the important industrial organism Escherichia coli. Recent efforts to engineer E. coli for improved tolerance to these toxins are also discussed.

  17. Spent Fuel Management in Bulgaria

    The report presents the legislative framework in the Republic of Bulgaria for spent fuel (SF) management; storage facilities for spent fuel (at reactor spent fuel storage/reactor pond, away from reactor spent fuel storage facility (SFSF) and the dry storage facility), as well as the SF transportation back to Russia. The policy of the Republic of Bulgaria regarding the management of SF and radioactive wastes (RAW) has been based on the moral principle of avoiding to impose undue burdens on future generations. (author)

  18. Spent fuel interim storage

    The official inauguration of the spent fuel interim storage took place on Monday July 28, 2003 at Cernavoda NNP. The inaugural event was attended by local and central public authority representatives, a Canadian Government delegation as well as newsmen from local and central mass media and numerous specialists from Cernavoda NPP compound. Mr Andrei Grigorescu, State Secretary with the Economy and Commerce Ministry, underlined in his talk the importance of this objective for the continuous development of nuclear power in Romania as well as for Romania's complying with the EU practice in this field. Also the excellent collaboration between the Canadian contractor AECL and the Romanian partners Nuclear Montaj, CITON, UTI, General Concret in the accomplishment of this unit at the planned terms and costs. On behalf of Canadian delegation, spoke Minister Don Boudria. He underlined the importance which the Canadian Government affords to the cooperation with Romania aiming at specific objectives in the field of nuclear power such as the Cernavoda NPP Unit 2 and spent fuel interim storage. After traditional cutting of the inaugural ribbon by the two Ministers the festivities continued on the Cernavoda NPP Compound with undersigning the documents regarding the project completion and a press conference

  19. Lignocellulose degradation mechanisms across the Tree of Life.

    Cragg, Simon M; Beckham, Gregg T; Bruce, Neil C; Bugg, Timothy Dh; Distel, Daniel L; Dupree, Paul; Etxabe, Amaia Green; Goodell, Barry S; Jellison, Jody; McGeehan, John E; McQueen-Mason, Simon J; Schnorr, Kirk; Walton, Paul H; Watts, Joy Em; Zimmer, Martin

    2015-12-01

    Organisms use diverse mechanisms involving multiple complementary enzymes, particularly glycoside hydrolases (GHs), to deconstruct lignocellulose. Lytic polysaccharide monooxygenases (LPMOs) produced by bacteria and fungi facilitate deconstruction as does the Fenton chemistry of brown-rot fungi. Lignin depolymerisation is achieved by white-rot fungi and certain bacteria, using peroxidases and laccases. Meta-omics is now revealing the complexity of prokaryotic degradative activity in lignocellulose-rich environments. Protists from termite guts and some oomycetes produce multiple lignocellulolytic enzymes. Lignocellulose-consuming animals secrete some GHs, but most harbour a diverse enzyme-secreting gut microflora in a mutualism that is particularly complex in termites. Shipworms however, house GH-secreting and LPMO-secreting bacteria separate from the site of digestion and the isopod Limnoria relies on endogenous enzymes alone. The omics revolution is identifying many novel enzymes and paradigms for biomass deconstruction, but more emphasis on function is required, particularly for enzyme cocktails, in which LPMOs may play an important role. PMID:26583519

  20. Solid state fermentation of Achras zapota lignocellulose by Phanerochaete chrysosporium.

    Ganesh Kumar, A; Sekaran, G; Krishnamoorthy, Sarayu

    2006-09-01

    The biological transformation of lignocellulose of Achras zapota by white rot fungi, Phanerochaete chrysosporium, in solid state fermentation (SSF) was studied for 28 days. The kinetic transformation of lignocellulose was monitored through the determination of acid soluble and acid insoluble lignin content, total organic carbon (TOC) and chemical oxygen demand (COD). The lignolytic enzymes, lignin peroxidase (LiP) and manganese peroxidase (MnP) were quantified on weekly intervals. The degradation of lignin and other structural moieties of A. zapota lignocellulose were confirmed by high performance liquid chromatography (HPLC), Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). The degradation of lignin was increased after 7 days of fermentation with the release of water soluble and fermentable products. The LiP and MnP activities were increased in the first week of SSF and lignin degradation was also set to increase. This was accompanied with increase in COD by 94.6% and TOC by 80% and lignin content was decreased by 76%. The maximum activities of the enzymes LiP and MnP in extracellular fluid of SSF under nitrogen limitation, at pH 5.0, at temperature 37 degrees C and at 60% humidity were 2100 U/L and 1200 U/L. PMID:16122921

  1. Unlocking the potential of lignocellulosic biomass through plant science.

    Marriott, Poppy E; Gómez, Leonardo D; McQueen-Mason, Simon J

    2016-03-01

    1366 I. 1366 II. 1367 III. 1368 IV. 1368 V. 1369 VI. 1370 VII. 1372 VIII. 1372 IX. 1376 X. 1377 1377 References 1377 SUMMARY: The aim of producing sustainable liquid biofuels and chemicals from lignocellulosic biomass remains high on the sustainability agenda, but is challenged by the costs of producing fermentable sugars from these materials. Sugars from plant biomass can be fermented to alcohols or even alkanes, creating a liquid fuel in which carbon released on combustion is balanced by its photosynthetic capture. Large amounts of sugar are present in the woody, nonfood parts of crops and could be used for fuel production without compromising global food security. However, the sugar in woody biomass is locked up in the complex and recalcitrant lignocellulosic plant cell wall, making it difficult and expensive to extract. In this paper, we review what is known about the major polymeric components of woody plant biomass, with an emphasis on the molecular interactions that contribute to its recalcitrance to enzymatic digestion. In addition, we review the extensive research that has been carried out in order to understand and reduce lignocellulose recalcitrance and enable more cost-effective production of fuel from woody plant biomass. PMID:26443261

  2. 1-Butyl-3-Methylimidazolium Chloride Pretreatment on Malaysia Lignocellulose Wastes

    Ionic liquids (ILs) are of great interest as potential solvents for the production of fuels from lignocellulose biomass which is a potential source of bio fuels. To study the effects of pretreatment, 1-butyl-3-methylimidazolium chloride ([B mim]Cl) was used to pretreat woody plants, kempas (Koompassia malaccensis) and jelutong (Dyera costulata), and non-woody plants, kenaf (Hibiscus cannabinus) and rice husk (Oryza sativa) at 120 degree Celsius for 24 h. Cellulose was regenerated by the addition of water. The cell wall composition and structure of the lignocellulose bio masses before and after the ILs pretreatment were observed and characterized using field emission scanning electron microscopy (FESEM), attenuated total reflectance fourier transform infrared (ATR FT-IR) spectroscopy, and X-ray diffraction (XRD). After the pretreatment, enzymatic hydrolysis was carried out to identify the total reducing sugars (TRS) yields using dinitrosalicylic acid (DNS) method. Regenerated lignocellulose bio masses resulted in high TRS yields compared to their counter-parts which are in agreement with the findings of FESEM, ATR FT-IR and XRD that exhibited regenerated cellulose were less crystalline and more amorphous upon IL pretreatment. Therefore, kempas and jelutong can be alternate sources for the bio fuels production. (author)

  3. Study of Lignocellulose/Epoxy Composites for Carbon-neutral Insulation Materials

    Komiya, Gen; Hayami, Tokusuke; Murayama, Kiyoko; Sato, Junichi; Kinoshita, Susumu; Todo, Yoko; Amano, Yoshihiko

    Carbon-neutral materials, which do not affect the density of CO2 in the atmosphere even if they burn, have attracted much attention form the viewpoint of environmental friendliness. In this study, lignocellulose/epoxy composites were newly prepared as carbon-neutral insulation materials, and their properties were evaluated. Hydrothermal reaction lignocellulose, which is composed of lignin and crystalline cellulose, was prepared by a treatment of corncob under high-pressure hot water at 190C, 1.8 MPa for 10min. The 13C-NMR spectra showed that the amounts of non-crystalline cellulose in the hydrothermal reaction lignocellulose were less than those of non-hydrothermal reaction lignocellulose. Moreover, hydrothermal reaction and oligoesterification lignocellulose was obtained by a reaction of maleic anhydride and glycidyl ether with the hydrothermal reaction lignocellulose. The epoxy resin containing the hydrothermal reaction and oligoesterification lignocellulose had lower water absorption and viscosity than those of the epoxy resin containing the non-hydrothermal reaction lignocellulose. The epoxy resin containing the hydrothermal reaction and oligoesterification lignocellulose with SiO2 fillers showed an insulation breakdown strength as same as conventional material (an epoxy resin containing SiO2 fillers). In addition, mechanical and thermal properties of the epoxy-based composite were also comparable with a conventional material. Therefore, the epoxy-based composite seems to be a candidate as practical carbon neutral insulation materials.

  4. Spent fuel management in Ukraine and spent fuel data tracking

    Ukraine has eleven WWER-1000 and two WWER-440 operating reactors at four nuclear plants. These reactors generated almost 45% of Ukraine's electricity. The last of the three RBMK-1000 reactors of Chornobyl NPP was shut down on December 15, 2000. Two WWER-1000 units (one at Khmelnytskyy NPP and another at Rivne NPP) are under construction. According to the Spent Fuel Management Program of Ukraine, which was approved in 2000, the state policy in the spent fuel management field is 'wait and see'. In order to implement this state policy the following problems should be solved: Construction of interim spent fuel storage facilities; Provision of spent fuel transportation from the reactor site to the interim storage facility; Provision of scientific and technical support of the spent fuel management. (author)

  5. Spent fuel management overview: a global perspective

    The paper defines the main spent fuel management strategies and options, highlights the challenges for spent fuel storage and gives an overview of the regional balances of spent fuel storage capacity and spent fuel arising. The relevant IAEA activities in the area of spent fuel management are summarised. (author)

  6. THE EFFECT OF ENZYMATIC HYDROLYSIS ON THE PROPERTIES OF PROTEIN HYDROLYSATE FROM PADDY MUSHROOM

    Tamtarini

    2010-11-01

    Full Text Available Protein hydrolysate was prepared from Paddy (Volvariella volvaceae mushroom. Hydrolysis uses commercially protease available Protamex with enzyme concentration of 0.1% (w/w. Hydrolysis was performed at three different temperatures (room temperature, 40 C, and 50 C with different incubation periods (60, 90, and 120 minutes. Enzyme inactivation was done in 90 C for 3 minutes. Yield and degree of hydrolysis ranged from 94.76% to 99.55% and 19.06% to 24.59%. Protein solubility was about 8911,8%. The longer time of hydrolysis, the darker the color of protein hydrolysate. Protein hydrolysate which has hydrolysis at 50 C for 120 minutes has the highest protein yield and the best sensory properties: 4.76 (taste liking, 3.68 (aroma liking, and 4.56 (overall liking. However, this protein hydrolysate has the potential for application as an ingredient in formulated diets.

  7. Use of UV absorbance To monitor furans in dilute acid hydrolysates of biomass.

    Martinez, A; Rodriguez, M E; York, S W; Preston, J F; Ingram, L O

    2000-01-01

    A simple method based on UV spectra was developed for the estimation of total furans (furfural and hydroxymethylfurfural) in hemicellulose hydrolysates. UV spectra of hemicellulose hydrolysate contained a single dominant peak at around 278 nm. Approximately two-thirds of this peak can be attributed to furan absorbance (furfural and hydroxymethylfurfural). At 284 nm, both furfural and hydroxymethylfurfural have equal absorbance on a weight basis. A comparison of HPLC determinations for different samples of hydrolysate was used to develop a simple equation that allows the accurate prediction of total furans based on the difference in absorbance at 284 and 320 nm. This method may prove useful for quality control applications during the production of biomass syrups using a dilute acid hydrolysis process and during treatments for the amelioration of toxins. Although furans represent only a portion of the toxins present in hemicellulose hydrolysates, the abundance of furans appears to serve as a useful marker to predict relative toxicity. PMID:10933839

  8. The hypolipidemic effect and antithrombotic activity of Mucuna pruriens protein hydrolysates.

    Herrera Chalé, Francisco; Ruiz Ruiz, Jorge Carlos; Betancur Ancona, David; Acevedo Fernández, Juan José; Segura Campos, Maira Rubi

    2016-01-01

    Hydrolysates and peptide fractions (PF) obtained from M. pruriens protein concentrates with commercial and digestive enzymatic systems were studied for their hypolipidemic and antithrombotic activities. Hydrolysates obtained with Pepsin-Pancreatin (PP) and their peptide fractions inhibited cholesterol micellar solubility with a maximum value of 1.83% in PP. Wistar rats were used to evaluate the hypolipidemic effect of hydrolysates and PF. The higher reductions of cholesterol and triglyceride levels were exhibited by PP and both peptide fractions 10 kDa from both hydrolysates showed the maximum antithrombotic activity with values of 33.33% for PF > 10 kDa from AF and 31.72% for PF > 10 kDa from PP. The results suggest that M. pruriens bioactive peptides with the hypolipidemic effect and antithrombotic activity might be utilized as nutraceuticals. PMID:26505152

  9. Physical and Oxidative Stability of Fish Oil-In-Water Emulsions Stabilized with Fish Protein Hydrolysates

    García Moreno, Pedro Jesús; Guadix, Antonio; Guadix, Emilia M.; Jacobsen, Charlotte

    2016-01-01

    The emulsifying and antioxidant properties of fish protein hydrolysates (FPH) for the physical and oxidative stabilization of 5% (by weight) fish oil-in-water emulsions were investigated. Muscle proteins from sardine (Sardina pilchardus) and small-spotted catshark (Scyliorhinus canicula) were...... hydrolyzed to degrees of hydrolysis (DH) of 3-4-5-6% with subtilisin. Sardine hydrolysates with low DH, 3% and 4%, presented the most effective peptides to physically stabilize emulsions with smaller droplet size. This implied more protein adsorbed at the interface to act as physical barrier against...... prooxidants. This fact might also be responsible for the higher oxidative stability of these emulsions, as shown by their lowest peroxide value and concentration of volatiles such as 1-penten-3-one and 1-penten-3-ol. Among the hydrolysates prepared from small-spotted catshark only the hydrolysate with DH 3...

  10. Angiotensin I converting enzyme inhibitory peptides purified from bovine skin gelatin hydrolysate.

    Kim, S K; Byun, H G; Park, P J; Shahidi, F

    2001-06-01

    Bovine skin gelatin was hydrolyzed with sequential protease treatments in the order of Alcalase, Pronase E, and collagenase using a three-step ultrafiltration membrane reactor. The molecular weight distributions of the first, second, and third hydrolysates were 4.8-6.6, 3.4-6.6, and 0.9-1.9 kDa, respectively. The angiotensin I converting enzyme (ACE) inhibitory activity of the third hydrolysate (IC(50) = 0.689 mg/mL) was higher than that of the first and second hydrolysates. Two different peptides showing strong ACE inhibitory activity were isolated from the hydrolysate using consecutive chromatographic methods including gel filtration chromatography, ion-exchange chromatography, and reversed-phase high-performance liquid chromatography. The isolated peptides were composed of Gly-Pro-Leu and Gly-Pro-Val and showed IC(50) values of 2.55 and 4.67 microM, respectively. PMID:11409999

  11. Spent fuel storage device

    Purpose: To obtain satisfactory countermeasure for system failures and fluctuations in fuel operation cycles. Constitution: A cooling unit comprising cooling plates of a quadrangle configuration and cooling pipes disposed therein in a zig-zag manner for directly cooling the pool water is disposed in a spent fuel storage pool. The inlet (or outlet) ends of the cooling pipe are respectively connected to the low temperature (or high temperature) sides of a cooling system for a ventilating auxiliary air conditioner cooling system respectively by way of pipeways, and automatic separation valves are interposed respectively to the pipeways. Upon failure of a fuel pool cooling and cleanup system, the automatic separation valve in the pipeway connected to the cooling system for the ventilating auxiliary air conditioner is opened and the cooling water cooled in the cooling system for instance, at 7 - 120C is circulated through the cooling plate to lower the temperature of the pool water. (Sekiya, K.)

  12. Spent fuel storage facility

    A diffusion-preventive device for the radioactivity of pool water is disposed in a pool chamber for accommodating a spent fuel storage chamber. The diffusion-preventive device comprises an air washer and a recycling blower which discharges air in the air washer to the pool chamber. In this air washer, not-activated pure water, etc. are supplied. The recycling blower is driven to introduce the air in the pool chamber to the air washer, and water is sprayed from a nozzle to moisten the air. In this way, the vapor pressure in the pool chamber can be increased and the amount of vapor generated from the pool can be decreased. The amount of radioactivity transferring from the poor water to the air can thereby be decreased and the amount of radioactivity released to the atmospheric air by means of ventilation air conditioning device can be decreased. (I.N.)

  13. Spent fuel management in Japan

    In Japan 52 commercial nuclear power units are now operated, and the total power generation capacity is about 45 GWe. The cumulative amount of spent fuel arising is about 13,500 tU as of March 1997. Spent fuel is reprocessed, and recovered nuclear materials are to be recycled in LWRs and FBRs. In February 1997 short-term policy measures were announced by the Atomic Energy Commission, which addressed promotion of reprocessing programme in Rokkasho, plutonium utilization in LWRs, spent fuel management, backend measures and FBR development. With regard to the spent fuel management, the policy measures included expansion of spent fuel storage capacity at reactor sites and a study on spent fuel storage away from reactor sites, considering the increasing amount of spent fuel arising. Research and development on spent fuel storage has been carried out, particularly on dry storage technology. Fundamental studies are also conducted to implement the burnup credit into the criticality safety design of storage and transportation casks. Rokkasho reprocessing plant is being constructed towards its commencement in 2003, and Pu utilization in LWRs will be started in 1999. Research and development of future recycling technology are also continued for the establishment of nuclear fuel cycle based on FBRs and LWRs. (author)

  14. Hydrolysed formula and risk of allergic or autoimmune disease: systematic review and meta-analysis

    Ierodiakonou, Despo; Khan, Tasnia; Chivinge, Jennifer; Robinson, Zoe; Geoghegan, Natalie; Jarrold, Katharine; Afxentiou, Thalia; Reeves, Tim; Cunha, Sergio; Trivella, Marialena; Garcia-Larsen, Vanessa; Leonardi-Bee, Jo

    2016-01-01

    Objective To determine whether feeding infants with hydrolysed formula reduces their risk of allergic or autoimmune disease. Design Systematic review and meta-analysis, as part of a series of systematic reviews commissioned by the UK Food Standards Agency to inform guidelines on infant feeding. Two authors selected studies by consensus, independently extracted data, and assessed the quality of included studies using the Cochrane risk of bias tool. Data sources Medline, Embase, Web of Science, CENTRAL, and LILACS searched between January 1946 and April 2015. Eligibility criteria for selecting studies Prospective intervention trials of hydrolysed cows’ milk formula compared with another hydrolysed formula, human breast milk, or a standard cows’ milk formula, which reported on allergic or autoimmune disease or allergic sensitisation. Results 37 eligible intervention trials of hydrolysed formula were identified, including over 19 000 participants. There was evidence of conflict of interest and high or unclear risk of bias in most studies of allergic outcomes and evidence of publication bias for studies of eczema and wheeze. Overall there was no consistent evidence that partially or extensively hydrolysed formulas reduce risk of allergic or autoimmune outcomes in infants at high pre-existing risk of these outcomes. Odds ratios for eczema at age 0-4, compared with standard cows’ milk formula, were 0.84 (95% confidence interval 0.67 to 1.07; I2=30%) for partially hydrolysed formula; 0.55 (0.28 to 1.09; I2=74%) for extensively hydrolysed casein based formula; and 1.12 (0.88 to 1.42; I2=0%) for extensively hydrolysed whey based formula. There was no evidence to support the health claim approved by the US Food and Drug Administration that a partially hydrolysed formula could reduce the risk of eczema nor the conclusion of the Cochrane review that hydrolysed formula could prevent allergy to cows’ milk. Conclusion These findings do not support current guidelines that recommend the use of hydrolysed formula to prevent allergic disease in high risk infants. Review registration PROSPERO CRD42013004252. PMID:26956579

  15. Uses of mechanically separated chicken meat for production from protein hydrolysates different proteolytic enzymes

    Mari Silvia Rodrigues de Oliveira; Felipe de Lima Franzen; Nelcindo Nascimento Terra

    2014-01-01

    The use of hydrolyzed protein, derived from animal and vegetable sources, in specific formulations, is an area of growing interest. The aim of this study was to develop different powder hydrolysates with high protein value, from the enzymatic hydrolysis of mechanically deboned meat (MDM), a byproduct of the poultry industry, which can be a low-cost source for the production of these hydrolysates. The raw material used was frozen poultry mechanically deboned meat (MDM) purchased from an abatto...

  16. Long-Term Fungal Inhibition by Pisum sativum Flour Hydrolysate during Storage of Wheat Flour Bread

    Rizzello, Carlo Giuseppe; Lavecchia, Anna; Gramaglia, Valerio; Gobbetti, Marco

    2015-01-01

    In order to identify antifungal compounds from natural sources to be used as ingredients in the bakery industry, water/salt-soluble extracts (WSE) from different legume flour hydrolysates obtained by the use of a fungal protease were assayed against Penicillium roqueforti DPPMAF1. The agar diffusion assays allowed the selection of the pea (Pisum sativum) hydrolysate as the most active. As shown by the hyphal radial growth rate, the WSE had inhibitory activity towards several fungi isolated fr...

  17. Antioxidant Effect and Water-Holding Capacity of Roselle (Hibiscus sabdariffa L.) Seed Protein Hydrolysates

    Fatoumata Tounkara; Bernard Sodio; Tidjani Amza; Guo-Wei Le; Yong-Hui Shi

    2013-01-01

    The aim of this study was to investigate the effect of in-vitro pepsin and pancreatin digestion of proteins extracted from Roselle seed on the production of bioactive peptides. Defatted Roselle seed flour was used to extract different protein fractions namely globulin, albumin and glutelin. The proteins were digested using pepsin (1 h) followed by pancreatin (1 h) in order to produce hydrolysates with good antioxidant activity. The prepared hydrolysates were as effective as antioxidants in mo...

  18. Industrial scale chromatographic separation of valuable compounds from biomass hydrolysates and side streams

    Saari, Pia

    2011-01-01

    Carbohydrates are composed of a number of various monosaccharides, glucose being the most abundant. Some of the monosaccharides are valuable compounds used in the food and pharmaceutical industries. They can be separated from biomass hydrolysates e.g. by chromatographic methods. In this thesis, chromatographic separation of valuable compounds using ion exchange resins was studied on an industrial scale. Of special interest were rare monosaccharides in biomass hydrolysates. A novel chroma...

  19. Study of Anti-Fatigue Effect in Rats of Ferrous Chelates Including Hairtail Protein Hydrolysates

    Saibo Huang; Huimin Lin; Shang-gui Deng

    2015-01-01

    The ability of ferrous chelates including hairtail protein hydrolysates to prevent and reduce fatigue was studied in rats. After hydrolysis of hairtail surimi with papain, the hairtail protein hydrolysates (HPH) were separated into three groups by range of relative molecular weight using ultrafiltration membrane separation. Hairtail proteins were then chelated with ferrous ions, and the antioxidant activity, the amino acid composition and chelation rate of the three kinds of ferrous chelates ...

  20. Comparison of the aggregation behavior of soy and bovine whey protein hydrolysates

    Kuipers, B.J.H.; Alting, A C; Gruppen, H.

    2007-01-01

    Abstract Soy-derived proteins (soy protein isolate, glycinin, and ß-conglycinin) and bovine whey-derived proteins (whey protein isolate, ¿-lactalbumin, ß-lactoglobulin) were hydrolyzed using subtilisin Carlsberg, chymotrypsin, trypsin, bromelain, and papain. The (in)solubility of the hydrolysates obtained was studied as a function of pH. At neutral pH, all soy-derived protein hydrolysates, particularly those from glycinin, obtained by hydrolysis with subtilisin Carlsberg, chymotrypsin, bromel...

  1. HYDROLYSIS OF WHEAT STRAW HEMICELLULOSE AND DETOXIFICATION OF THE HYDROLYSATE FOR XYLITOL PRODUCTION

    Junping Zhuang; Ying Liu; Zhen Wu; Yong Sun; Lu Lin

    2009-01-01

    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 ...

  2. WPC Hydrolysates Obtained by the Action of a Pancreatin: Preparation, Analysis and Phenylalanine Removal

    Larissa L. Amorin; Mauro R. Silva; Viviane D.M. Silva; Maite C. Silva; Marialice P.C. Silvestre

    2011-01-01

    The aim of this work was to use a pancreatin to obtain Whey Protein Concentrate (WPC) hydrolysates with high degree of hydrolysis, appropriate peptide profiles from the nutritional point of view as well as with reduced Phenylalanine (Phe) content. Six hydrolysates were prepared by varying the enzyme: Substrate ratio and the substrate concentration. The degree of hydrolysis was calculated by the ratio between a-amino and total nitrogen. The analysis of peptide profile involved the fractionatio...

  3. Moisture sorption and stickiness behaviour of hydrolysed whey protein/lactose powders

    Hogan, S.; O’Callaghan, D.

    2013-01-01

    The potentially negative effects of low molecular weight disaccharides, especially lactose, on spray-drying efficiency and storage stability of dairy powders are often counterbalanced by the presence of intact milk proteins. Hydrolysis of proteins, however, may impair such protective effects and contribute to a loss in production performance. Hydrolysed or non-hydrolysed whey protein/lactose (WP/L) dispersions were spray dried, in order to examine the effects of protein hydrolysis on relaxati...

  4. Collagen Metabolism of Human Osteoarthritic Articular Cartilage as Modulated by Bovine Collagen Hydrolysates

    Schadow, Saskia; Siebert, Hans-Christian; Lochnit, Gnter; Kordelle, Jens; Rickert, Markus; Steinmeyer, Jrgen

    2013-01-01

    Destruction of articular cartilage is a characteristic feature of osteoarthritis (OA). Collagen hydrolysates are mixtures of collagen peptides and have gained huge public attention as nutriceuticals used for prophylaxis of OA. Here, we evaluated for the first time whether different bovine collagen hydrolysate preparations indeed modulate the metabolism of collagen and proteoglycans from human OA cartilage explants and determined the chemical composition of oligopeptides representing collagen ...

  5. Antioxidant properties of carp (Cyprinus carpio L.) protein ex vivo and in vitro hydrolysates.

    Borawska, Justyna; Darewicz, Ma?gorzata; Vegarud, Gerd E; Minkiewicz, Piotr

    2016-03-01

    The presence of specific peptides with antioxidant properties released during carp protein ex vivo and in vitro hydrolysis by human/porcine digestive enzymes, respectively, was examined. Based on the results of the in silico data analysis, antioxidant peptides were selected for subsequent identification in the digests/hydrolysates. Carp proteins were more resistant to hydrolysis by porcine enzymes than by human digestive juices. The sarcoplasmic proteins were hydrolyzed faster than the myofibrillar ones by both human/porcine enzymes. The in vitro myofibrillar protein hydrolysate showed the highest ABTS(+) scavenging activity (?232.3 TEAC, ?M Trolox/g), whereas the ex vivo hydrolysate of sarcoplasmic proteins showed the highest DPPH scavenging activity (?88?M/g) and reducing power. Five antioxidant peptides were identified in carp protein ex vivo and in vitro hydrolysates: FIKK, HL, IY, PW, VY. The peptide HL from myofibrillar proteins was identified only in the ex vivo hydrolysate, whereas the peptide PW from sarcoplasmic proteins was identified only in the in vitro hydrolysate. PMID:26471617

  6. Antioxidative and functional properties of protein hydrolysate from defatted skipjack (Katsuwonous pelamis) roe.

    Intarasirisawat, Rossawan; Benjakul, Soottawat; Visessanguan, Wonnop; Wu, Jianping

    2012-12-15

    Antioxidative and functional properties of protein hydrolysate from defatted skipjack (Katsuwonous pelamis) roe, hydrolysed by Alcalase 2.4 L (RPH) with different degrees of hydrolysis (DH) at various concentrations were examined. As DH increased, the reduction of DPPH, ABTS radicals scavenging activities and reducing power were noticeable (p<0.05). The increases in metal chelating activity and superoxide scavenging activity were attained with increasing DH (p<0.05). However, chelating activity gradually decreased at DH above 30%. All activities except superoxide anion radical scavenging activity increased as the concentration of hydrolysate increased (p<0.05). Hydrolysis using Alcalase could increase protein solubility to above 80% over a wide pH range (2-10). The highest emulsion ability index (EAI) and foam stability (FS) of hydrolysates were observed at low DH (5%) (p<0.05). Concentrations of hydrolysates determined interfacial properties differently, depending on DH. The molecular weight distribution of RPH with 5%DH (RPH5) was determined using Sephadex G-75 column. Two major peaks with the molecular weight of 57.8 and 5.5kDa were obtained. Fraction with MW of 5.5 had the strongest metal chelating activity and ABTS radical scavenging activity. The results reveal that protein hydrolysates from defatted skipjack roe could be used as food additives possessing both antioxidant activity and functional properties. PMID:22980906

  7. Antioxidative activities of hydrolysates from edible birds nest using enzymatic hydrolysis

    Muhammad, Nurul Nadia; Babji, Abdul Salam; Ayub, Mohd Khan

    2015-09-01

    Edible bird's nest protein hydrolysates (EBN) were prepared via enzymatic hydrolysis to investigate its antioxidant activity. Two types of enzyme (alcalase and papain) were used in this study and EBN had been hydrolysed with different hydrolysis time (30, 60, 90 and 120 min). Antioxidant activities in EBN protein hydrolysate were measured using DPPH, ABTS+ and Reducing Power Assay. From this study, increased hydrolysis time from 30 min to 120 min contributed to higher DH, as shown by alcalase (40.59%) and papain (24.94%). For antioxidant assay, EBN hydrolysed with papain showed higher scavenging activity and reducing power ability compared to alcalase. The highest antioxidant activity for papain was at 120 min hydrolysis time with ABTS (54.245%), DPPH (49.78%) and Reducing Power (0.0680). Meanwhile for alcalase, the highest antioxidant activity was at 30 min hydrolysis time. Even though scavenging activity for EBN protein hydrolysates were high, the reducing power ability was quite low as compared to BHT and ascorbic Acid. This study showed that EBN protein hydrolysate with alcalase and papain treatments potentially exhibit high antioxidant activity which have not been reported before.

  8. Antioxidant Activities of Protein Hydrolysates from Little Hairtail (Trichiurus haumela of East China Sea

    Ting Jin

    2015-02-01

    Full Text Available This study investigated antioxidant properties of the little hairtail (Trichiurus haumela protein hydrolysates obtained by commercial protease of Alcalase through using various antioxidant assays, including reducing power and free radical scavenging activities. The molecular mass distribution of hydrolysates was also examined to evaluate their relationship with antioxidant activity. The results showed that little hairtail protein hydrolysates had good ability to donate electron or hydrogen and scavenge DPPH, hydroxyl and superoxide anion radicals. The highest value of reducing power and radical scavenging activities was 1.89, 46.15% (DPPH radical, 75.65% (hydroxyl radical and 82.5% (superoxide anion radical, respectively. The reducing power and free radical scavenging activities of little hairtail protein hydrolysates were related to hydrolysis time to some extent. The molecular mass distribution of hydrolysates showed that their molecular mass was between 337 and 6007Da, which indicated that little hairtail protein hydrolysates were mainly composed of low molecular peptides with antioxidant activity. Conclusively, the little hairtail protein was a good natural source for producing antioxidants, which could be used as antioxidant ingredient with potential applications in various food products.

  9. Antioxidant activity of protein hydrolysates derived from threadfin bream surimi byproducts.

    Wiriyaphan, Chompoonuch; Chitsomboon, Benjamart; Yongsawadigul, Jirawat

    2012-05-01

    Antioxidant activities of protein hydrolysates from threadfin bream surimi wastes, including frame, bone and skin (FBS) and refiner discharge (RD), were investigated. FBS and RD were rich in Lys, Glu, Gly, Pro, Asp, Leu, His, Tyr and Phe. FBS was hydrolysed to a greater extent than RD regardless of proteinases tested (Virgibacillus sp. SK33 proteinase, Alcalase, pepsin and trypsin). Pepsin-hydrolysed FBS, at a 5% degree of hydrolysis (DH), showed the highest antioxidant activity based on 2,2'-azinobis (3-ethyl-benzothiazoline-6-sulphonate) (ABTS) radical (0.455±0.054mg Trolox equivalents/mg leucine equivalents), ferric reducing antioxidant power (FRAP) (0.221±0.005mM Trolox equivalents) and inhibition of β-carotene bleaching assays. FBS hydrolysates showed higher antioxidant activity based on chemical assays than their RD counterparts. However, FBS and RD hydrolysates protected HepG2 cells against tert-butyl hydroperoxide-induced oxidative damage to a similar extent. Therefore, FBS and RD hydrolysates have a potential as antioxidative neutraceutical ingredients. PMID:26434269

  10. Management of Spent Fuel in Germany

    This presentation gives an overview on the inventory of radioactive waste and spent fuel in Germany, the state of commissioning of the on-site storages for spent fuel and the balance of reprocessing of spent fuel. (author)

  11. Continuous succinic acid production by Actinobacillus succinogenes on xylose-enriched hydrolysate

    Bradfield, Michael F. A.; Mohagheghi, Ali; Salvachúa, Davinia; Smith, Holly; Black, Brenna A.; Dowe, Nancy; Beckham, Gregg T; Nicol, Willie

    2015-01-01

    Background Bio-manufacturing of high-value chemicals in parallel to renewable biofuels has the potential to dramatically improve the overall economic landscape of integrated lignocellulosic biorefineries. However, this will require the generation of carbohydrate streams from lignocellulose in a form suitable for efficient microbial conversion and downstream processing appropriate to the desired end use, making overall process development, along with selection of appropriate target molecules, ...

  12. Selection of the Strain Lactobacillus acidophilus ATCC 43121 and Its Application to Brewers' Spent Grain Conversion into Lactic Acid

    Rossana Liguori; Carlos Ricardo Soccol; Luciana Porto de Souza Vandenberghe; Adenise Lorenci Woiciechowski; Elena Ionata; Loredana Marcolongo; Vincenza Faraco

    2015-01-01

    Six Lactobacillus strains were analyzed to select a bacterium for conversion of brewers spent grain (BSG) into lactic acid. Among the investigated strains, L. acidophilus ATCC 43121 showed the highest yield of lactic acid production (16.1?g/L after 48 hours) when grown in a synthetic medium. It was then analyzed for its ability to grow on the hydrolysates obtained from BSG after acid-alkaline (AAT) or aqueous ammonia soaking (AAS) pretreatment. The lactic acid production by L. acidophilus AT...

  13. DEVELOPING AN ASSAY TO DETERMINE BIOAVAILABILITY OF LIGNOCELLULOSE IN CORN STOVER

    Lignocellulose is said to be the most abundant compound on earth and is an excellent renewable feedstock for the production of ethanol as an alternative fuel source. Corn stover is made of lignocellulose and may prove to be an essentially free renewable energy resource. The goal of this research i...

  14. Structural reorganisation of cellulose fibrils in hydrothermally deconstructed lignocellulosic biomass and relationships with enzyme digestibility

    Ibbett, Roger; Gaddipati, Sanyasi; Hill, Sandra; Tucker, Greg

    2013-01-01

    Background: The investigation of structural organisation in lignocellulose materials is important to understand changes in cellulase accessibility and reactivity resulting from hydrothermal deconstruction, to allow development of strategies to maximise bioethanol process efficiencies. To achieve progress, wheat straw lignocellulose and comparative model wood cellulose were characterised following increasing severity of hydrothermal treatment. Powder and fibre wide-angle X-ray diff...

  15. Disposal of spent nuclear fuel

    1979-12-01

    This report addresses the topic of the mined geologic disposal of spent nuclear fuel from Pressurized Water Reactors (PWR) and Boiling Water Reactors (BWR). Although some fuel processing options are identified, most of the information in this report relates to the isolation of spent fuel in the form it is removed from the reactor. The characteristics of the waste management system and research which relate to spent fuel isolation are discussed. The differences between spent fuel and processed HLW which impact the waste isolation system are defined and evaluated for the nature and extent of that impact. What is known and what needs to be determined about spent fuel as a waste form to design a viable waste isolation system is presented. Other waste forms and programs such as geologic exploration, site characterization and licensing which are generic to all waste forms are also discussed. R and D is being carried out to establish the technical information to develop the methods used for disposal of spent fuel. All evidence to date indicates that there is no reason, based on safety considerations, that spent fuel should not be disposed of as a waste.

  16. Disposal of spent nuclear fuel

    This report addresses the topic of the mined geologic disposal of spent nuclear fuel from Pressurized Water Reactors (PWR) and Boiling Water Reactors (BWR). Although some fuel processing options are identified, most of the information in this report relates to the isolation of spent fuel in the form it is removed from the reactor. The characteristics of the waste management system and research which relate to spent fuel isolation are discussed. The differences between spent fuel and processed HLW which impact the waste isolation system are defined and evaluated for the nature and extent of that impact. What is known and what needs to be determined about spent fuel as a waste form to design a viable waste isolation system is presented. Other waste forms and programs such as geologic exploration, site characterization and licensing which are generic to all waste forms are also discussed. R and D is being carried out to establish the technical information to develop the methods used for disposal of spent fuel. All evidence to date indicates that there is no reason, based on safety considerations, that spent fuel should not be disposed of as a waste

  17. Spent fuel treatment in Japan

    In Japan, 52 nuclear power reactors are operating with a total power generation capacity of 45 GWe. The cumulative amount of spent fuel arising, as of March 1998, is about 14,700 W. Spent fuel is reprocessed and recovered nuclear materials are to be recycled in LWRs and FBRs. Pu utilization in LWRs will commence in 1999. In January 1997, short-term policy measures were announced by the Atomic Energy Commission, which addressed promotion of the reprocessing programme in Rokkasho, plutonium utilization in LWRs, spent fuel management, back-end measures and FBR development. With regard to the spent fuel management, the policy measures included expansion of spent fuel storage capacity at reactor sites and a study on spent fuel storage away-from-reactor sites, considering the increasing amount of spent fuel arising. Valuable experience was been accumulated at the Tokai Reprocessing Plant (TRP), from the start of hot operation in 1977 up to now. The role of the TRP will be changed from an operation-oriented to a more R and D oriented facility, when PNC is reorganized into the new organization JNC. The Rokkasho reprocessing plant is under construction and is expected to commence operation in 2003. R and D of future recycling technologies is also continued for the establishment of a nuclear fuel cycle based on FBRs and LWRs. (author)

  18. Comparative environmental performance of lignocellulosic ethanol from different feedstocks

    A renewable biofuel economy is projected as a pathway to decrease dependence on fossil fuels as well as to reduce greenhouse gases (GHG) emissions. Ethanol produced on large-scale from lignocellulosic raw materials is considered the most potential next generation automotive fuel. In this paper, a Life Cycle Assessment model was developed to evaluate the environmental implications of the production of ethanol from five lignocellulosic materials: alfalfa stems, poplar, Ethiopian mustard, flax shives and hemp hurds and its use in passenger cars. Two ethanol-based fuel applications, E10 (a mixture of 10% ethanol and 90% gasoline by volume) and E85 (85% ethanol and 15% gasoline by volume) were assessed and the results were compared to those of conventional gasoline (CG) in an equivalent car. The environmental performance was assessed in terms of fossil fuels requirements, global warming, photochemical oxidant formation, acidification and eutrophication by means of the Life Cycle Assessment (LCA) methodology in order to identify the best environmental friendly lignocellulosic source. The results show that, compared to CG, life cycle greenhouse gases emissions are lower for etanol blends, specifically up to 145% lower for E85-fueled car derived from Ethiopian mustard. This crop is also the best option in terms of eutrophying emissions regardless the ratio of ethanol in the blend. In the remaining impact categories, other feedstocks are considered beneficial, that is, poplar in the case of photochemical oxidants formation and flax shives for acidification. Concerning fossil fuels requirements, decreases up to 10% and 63% for E10 and E85 derived from hemp hurds and Ethiopian mustard, respectively, were obtained. According to the results, the study clearly demonstrates the importance of using low intensive energy and high biomass yield crops. LCA procedure helps to identify the key areas in the ethanol production life cycle where the researchers and technicians need to work to improve the environmental performance. Technological development could help in lowering both the environmental impact and the prices of the ethanol fuels. (author)

  19. Dielectric studies of environmentally friendly and flexible lignocelluloses fibrils for miniaturization of patch antenna

    Razaq, Aamir; Khan, Asim Ali; Asif, M. H.; Iqbal, Shahid; Ali, Jawad; Manzoor, Faisal; Awan, M. S.

    2015-10-01

    Naturally, existing lignocelluloses fibers showed outstanding potential in paper industry and other conventional applications. On the other hand, lignocellulose fibers are suitable candidate for high-tech applications under the scope of abundance, flexibility, light-weight and environment friendliness. In this study, paper sheets were prepared from lignocelluloses fibers extracted from self-growing plant, typha angustifolia. Lignocelluloses paper sheets were characterized for scanning electron microscopy (SEM), universal testing machine (UTM) and vector network analyzer (VNA). Flexible paper sheets displayed a tensile strength of 9.1 MPa and further used as a substrate in patch antenna to observe dielectric characteristics. The patch antenna is designed at 5.1 GHz which showed return loss less than -10 dB and dielectric constant 3.71. The use of lignocelluloses paper sheet as a substrate in patch antenna will provide the opportunity of miniaturization of size and weight in comparison of a jean substrate based antenna.

  20. Improved Functional Characteristics of Whey Protein Hydrolysates in Food Industry.

    Jeewanthi, Renda Kankanamge Chaturika; Lee, Na-Kyoung; Paik, Hyun-Dong

    2015-01-01

    This review focuses on the enhanced functional characteristics of enzymatic hydrolysates of whey proteins (WPHs) in food applications compared to intact whey proteins (WPs). WPs are applied in foods as whey protein concentrates (WPCs), whey protein isolates (WPIs), and WPHs. WPs are byproducts of cheese production, used in a wide range of food applications due to their nutritional validity, functional activities, and cost effectiveness. Enzymatic hydrolysis yields improved functional and nutritional benefits in contrast to heat denaturation or native applications. WPHs improve solubility over a wide range of pH, create viscosity through water binding, and promote cohesion, adhesion, and elasticity. WPHs form stronger but more flexible edible films than WPC or WPI. WPHs enhance emulsification, bind fat, and facilitate whipping, compared to intact WPs. Extensive hydrolyzed WPHs with proper heat applications are the best emulsifiers and addition of polysaccharides improves the emulsification ability of WPHs. Also, WPHs improve the sensorial properties like color, flavor, and texture but impart a bitter taste in case where extensive hydrolysis (degree of hydrolysis greater than 8%). It is important to consider the type of enzyme, hydrolysis conditions, and WPHs production method based on the nature of food application. PMID:26761849

  1. Assessment of spent fuel cooling

    The paper presents the methodology, the findings, and the conclusions of a study that was done by the Nuclear Regulatory Commission's Office for Analysis and Evaluation of Operational Data (AEOD) on loss of spent fuel pool cooling. The study involved an examination of spent fuel pool designs, operating experience, operating practices, and procedures. AEOD's work was augmented in the area of statistics and probabilistic risk assessment by experts from the Idaho Nuclear Engineering Laboratory. Operating experience was integrated into a probabilistic risk assessment to gain insight on the risks from spent fuel pools

  2. Assessment of spent fuel cooling

    Ibarra, J.G.; Jones, W.R.; Lanik, G.F. [and others

    1997-02-01

    The paper presents the methodology, the findings, and the conclusions of a study that was done by the Nuclear Regulatory Commission`s Office for Analysis and Evaluation of Operational Data (AEOD) on loss of spent fuel pool cooling. The study involved an examination of spent fuel pool designs, operating experience, operating practices, and procedures. AEOD`s work was augmented in the area of statistics and probabilistic risk assessment by experts from the Idaho Nuclear Engineering Laboratory. Operating experience was integrated into a probabilistic risk assessment to gain insight on the risks from spent fuel pools.

  3. Pyrolysis Strategies for Effective Utilization of Lignocellulosic and Algal Biomass

    Maddi, Balakrishna

    Pyrolysis is a processing technique involving thermal degradation of biomass in the absence of oxygen. The bio-oils obtained following the condensation of the pyrolysis vapors form a convenient starting point for valorizing the major components of lignocellulosic as well as algal biomass feed stocks for the production of fuels and value-added chemicals. Pyrolysis can be implemented on whole biomass or on residues left behind following standard fractionation methods. Microalgae and oil seeds predominantly consist of protein, carbohydrate and triglycerides, whereas lignocellulose is composed of carbohydrates (cellulose and hemicellulose) and lignin. The differences in the major components of these two types of biomass will necessitate different pyrolysis strategies to derive the optimal benefits from the resulting bio-oils. In this thesis, novel pyrolysis strategies were developed that enable efficient utilization of the bio-oils (and/or their vapors) from lignocellulose, algae, as well as oil seed feed stocks. With lignocellulosic feed stocks, pyrolysis of whole biomass as well as the lignin residue left behind following well-established pretreatment and saccharification (i.e., depolymerization of cellulose and hemicellulose to their monomeric-sugars) of the biomass was studied with and without catalysts. Following this, pyrolysis of (lipid-deficient) algae and lignocellulosic feed stocks, under similar reactor conditions, was performed for comparison of product (bio-oil, gas and bio-char) yields and composition. In spite of major differences in component bio-polymers, feedstock properties relevant to thermo-chemical conversions, such as overall C, H and O-content, C/O and H/C molar ratio as well as calorific values, were found to be similar for algae and lignocellulosic material. Bio-oil yields from algae and some lignocellulosic materials were similar; however, algal bio-oils were compositionally different and contained several N-compounds (most likely from protein degradation). Algal bio-char also had a significantly higher N-content. Overall, our results suggest that it is feasible to convert algal cultures deficient in lipids, such as nuisance algae obtained from natural blooms, into liquid fuels by thermochemical methods. Next, pyrolysis characteristics of each of the major components present in lignocellulosic as well as algal biomass were studied independently in a thermo-gravimetric analyzer, using model compounds. From those studies, we have established that, with algae and oil seed feed stocks, triglycerides degrade at distinctly higher temperatures (T>350 C) compared to both protein and carbohydrate fractions (T ~ 250-350 C). Similar trend was not seen for lignocellulosic biomass, where degradation temperature interval of lignin overlapped with that of carbohydrates. This unique trend observed for algal biomass (and oil seeds) can be exploited in multiple ways. First, it permits to separately collect high value triglyceride degradation products not contaminated with N-compounds from protein and oxygenates from carbohydrates; this observation formed the basis of a novel "pyrolytic fractionation technique" developed in this thesis. Second, it led to the development of a new and simple analytical method for rapid estimation of the triglyceride content of oleaginous feed stocks. Pyrolytic fractionation is a two-step pyrolysis approach that can be implemented for oleaginous feed stocks (algae and oil-seeds) to separately recover triglyceride degradation products as a "high-quality" bio-oil fraction. The first step is a low-temperature pyrolysis (T ~ 300-320 C) to produce bio-oils from degradation of protein and carbohydrate fractions. Solid residues left behind can subsequently be subjected to a second higher temperature pyrolysis (T ~ 420-430 C) to volatilize and/or degrade triglycerides to produce fatty acids and their derivatives (such as mono-, di- and tri-glycerides) and long chain hydrocarbons. Proof-of-concept micro-pyrolyser (Pyroprobe) and lab-scale fixed-bed experiments were performed using oleaginous algae (Chlorella Sp.) to establish pyrolytic fractionation technique and also to determine the yields of triglyceride-specific bio-oils. As expected, triglyceride-specific bio-oils have hydrocarbons and free fatty acids that were nearly free of water, organic acids and carbohydrate degradation products. Another unique feature of the fractional pyrolysis method is that it allows upgrading of the triglyceride-specific bio-oil vapors via in situ gas-phase hydro-deoxygenation to drop-in fuels (hydrocarbons), without the need to condense the vapors. Similarly, these vapors can also be converted to other value-added products such as fatty acid methyl esters and amides though efficient catalytic and non-catalytic in situ gas-phase conversion methods. Energy requirements for this new pyrolytic fractionation method were also assessed, using energy estimates for the individual steps obtained via differential scanning calorimetry experiments. A comparison of these energy needs against those of alternative thermal processing methods of algae (hydro-thermal processing) proposed in the literature established the viability of this new method. Finally, a new TGA-based analytical method was developed in this thesis for rapid quantification of the triglyceride content of oleaginous feed stocks, by exploiting the non-overlapping thermal degradation range of triglycerides and the other major components.

  4. Cellulosic ethanol: progress towards a simulation model of lignocellulosic biomass

    A CHARMM molecular mechanics force field for lignin is derived. Parameterization is based on reproducing quantum mechanical data of model compounds. Partial atomic charges are derived by the examination of methoxybenzene: water interactions. Dihedral parameters are optimized by fitting to critical rotational potentials, and bonded parameters are obtained by optimizing vibrational frequencies and normal modes. The force field is validated by performing a molecular dynamics simulation of a crystal of a lignin fragment molecule and comparing simulation-derived structural features with experimental results. Together with the existing force field for polysaccharides, this work will enable full simulations of lignocellulose

  5. Mixed Enzyme Systems for Delignification of Lignocellulosic Biomass

    Elisa M. Woolridge

    2014-01-01

    Full Text Available The application of enzymes such as laccase and xylanase for the preparation of cellulose from lignocellulosic material is an option for those industries seeking to reduce the use of chlorine-containing bleach agents, thus minimizing the environmental impact of their processes. Mixed hydrolytic and oxidative enzyme systems have been well described in the context of biopulping, and thus provide good precedent regarding effectiveness, despite the susceptibility of xylanase to inactivation by laccase-generated oxidants. This paper examines the progress towards development of sequential and simultaneous mixed enzyme systems to accomplish delignification.

  6. WWER spent fuel storage

    Selection criteria for PAKS NPP dry storage system are outlined. They include the following: fuel temperature in storage; sub-criticality assurance (avoidance of criticality for fuel in the unirradiated condition without having to take credit for burn-up); assurance of decay heat removal; dose uptake to the operators and public; protection of environment; volume of waste produced during operation and decommissioning; physical protection of stored irradiated fuel assemblies; IAEA safeguards assurance; storage system versus final disposal route; cost of construction and extent of technology transfer to Hungarian industry. Several available systems are evaluated against these criteria, and as a result the GEC ALSTHOM Modular Vault Dry Store (MVDS) system has been selected. The MVDS is a passively cooled dry storage facility. Its most important technical, safety, licensing and technology transfer characteristics are outlined. On the basis of the experience gained some key questions and considerations related to the East European perspective in the field of spent fuel storage are discussed. 8 figs

  7. Preparation of Low-phenylalanine Whey Hydrolysates, Using Papain and Pancreatin Immobilized on Activated Carbon and Alumina

    Viviane D.M. Silva; Leticia M. De Marco; Wendel O. Afonso; Daniella C.F. Lopes; JoseN. Januario; Marcos J.B. Aguiar; Ana Lucia P. Starling; Marialice P.C. Silvestre

    2007-01-01

    This study involves the preparation of whey hydrolysates with low phenylalanine (Phe) content aiming the treatment of phenylketonuria. For hydrolysing the proteins, two enzymes were used, papain and pancreatin, in an immobilized form, on Activated Carbon (AC) and alumina (AL) and three enzyme: substrate ratios (E:S) were tested for each enzyme. Activated carbon was used to remove Phe from hydrolysates. The second order spectrophotometry was used to evaluate the efficiency of Phe removal as we...

  8. Angiotensin-I Converting Enzyme (ACE) Inhibitory and Anti-Oxidant Activities of Sea Cucumber (Actinopyga lecanora) Hydrolysates

    Raheleh Ghanbari; Mohammad Zarei; Afshin Ebrahimpour; Azizah Abdul-Hamid; Amin Ismail; Nazamid Saari

    2015-01-01

    In recent years, food protein-derived hydrolysates have received considerable attention because of their numerous health benefits. Amongst the hydrolysates, those with anti-hypertensive and anti-oxidative activities are receiving special attention as both activities can play significant roles in preventing cardiovascular diseases. The present study investigated the angiotensin-I converting enzyme (ACE) inhibitory and anti-oxidative activities of Actinopyga lecanora (A. lecanora) hydrolysates,...

  9. Effect of Peptide Size on Antioxidant Properties of African Yam Bean Seed (Sphenostylis stenocarpa) Protein Hydrolysate Fractions

    Ajibola, Comfort F.; Fagbemi, Tayo N.; Joseph B. Fashakin; Rotimi E. Aluko

    2011-01-01

    Enzymatic hydrolysate of African yam bean seed protein isolate was prepared by treatment with alcalase. The hydrolysate was further fractionated into peptide sizes of < 1, 1–3, 3–5 and 5–10 kDa using membrane ultrafiltration. The protein hydrolysate (APH) and its membrane ultrafiltration fractions were assayed for in vitro antioxidant activities. The < 1 kDa peptides exhibited significantly better (p < 0.05) ferric reducing power, diphenyl-1-picryhydradzyl (DPPH) and hydroxyl radical...

  10. Effect of nitrogen source concentration on curdlan production by Agrobacterium sp. ATCC 31749 grown on prairie cordgrass hydrolysates.

    West, Thomas P

    2016-01-01

    The effect of nitrogen source concentration on the production of the polysaccharide curdlan by the bacterium Agrobacterium sp. ATCC 31749 from hydrolysates of prairie cordgrass was examined. The highest curdlan concentrations were produced by ATCC 31749 when grown on a medium containing a solids-only hydrolysate and the nitrogen source ammonium phosphate (2.2mM) or on a medium containing a complete hydrolysate and 3.3mM ammonium phosphate. The latter medium sustained a higher level of bacterial curdlan production than the former medium after 144hr. Biomass production by ATCC 31749 was highest after 144hr when grown on a medium containing a solids-only hydrolysate and 2.2 or 8.7mM ammonium phosphate. On the medium containing the complete hydrolysate, biomass production by ATCC 31749 was highest after 144hr when 3.3mM ammonium phosphate was present. Bacterial biomass production after 144hr was greater on the complete hydrolysate medium compared to the solids-only hydrolysate medium. Curdlan yield produced by ATCC 31749 after 144hr from the complete hydrolysate medium containing 3.3mM ammonium phosphate was higher than from the solids-only hydrolysate medium containing 2.2mM ammonium phosphate. PMID:25397813

  11. Antioxidant Activity of Fish Protein Hydrolysates in in vitro Assays and in Oil-in-Water Emulsions

    Farvin, Sabeena; Andersen, Lisa Lystbæk; Jacobsen, Charlotte; Nielsen, Henrik Hauch; Jessen, Flemming

    The aim of this study was to screen different protein hydrolysates with respect to their antioxidative properties in order to select the most promising extracts for further evaluation in oil-in-water emulsions. Three fractions of protein hydrolysates (Crude, >5kDa and 5kDa, 3-5kDa and......The aim of this study was to screen different protein hydrolysates with respect to their antioxidative properties in order to select the most promising extracts for further evaluation in oil-in-water emulsions. Three fractions of protein hydrolysates (Crude, >5kDa and 5kDa, 3-5kDa and...

  12. Uses of mechanically separated chicken meat for production from protein hydrolysates different proteolytic enzymes

    Mari Silvia Rodrigues de Oliveira

    2014-02-01

    Full Text Available The use of hydrolyzed protein, derived from animal and vegetable sources, in specific formulations, is an area of growing interest. The aim of this study was to develop different powder hydrolysates with high protein value, from the enzymatic hydrolysis of mechanically deboned meat (MDM, a byproduct of the poultry industry, which can be a low-cost source for the production of these hydrolysates. The raw material used was frozen poultry mechanically deboned meat (MDM purchased from an abattoir in southern Brazil, before use it was thawed under refrigeration and homogenized in a processor by 2 minutes. Three commercial enzymes were used, Papain, Protamex® and Flavourzyme®. The hydrolysis occurred in a thermostatized bath with temperature, time and pH controlled. Proximal composition of the raw material and lyophilized hydrolysates, control analysis such as hydrolysis degree of hydrolysis, protein, total solids, ash and amino acid characterization of the hydrolysates were performed. The results were evaluated by analysis of variance and Tukey’s averages test. The hydrolyzed obtained from the papain enzyme showed the best behavior, followed by Protamex and Flavourzyme. The hydrolysates from papain enzyme had higher protein content, soluble solids and lower ash content compared to other hydrolysates. The amino acid composition showed that the hydrolyzate from papain has a closer composition to what is recommended by the control organs. It was concluded that the protein hydrolysates obtained from mechanically deboned chicken had high protein content characterizing them as a promising raw material in the formulation of special diets.

  13. Active Interrogation for Spent Fuel

    Swinhoe, Martyn Thomas [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Dougan, Arden [National Nuclear Security Administration (NNSA), Washington, DC (United States)

    2015-11-05

    The DDA instrument for nuclear safeguards is a fast, non-destructive assay, active neutron interrogation technique using an external 14 MeV DT neutron generator for characterization and verification of spent nuclear fuel assemblies.

  14. Intermodal transportation of spent fuel

    Concepts for transportation of spent fuel in rail casks from nuclear power plant sites with no rail service are under consideration by the US Department of Energy in the Commercial Spent Fuel Management program at the Pacific Northwest Laboratory. This report identifies and evaluates three alternative systems for intermodal transfer of spent fuel: heavy-haul truck to rail, barge to rail, and barge to heavy-haul truck. This report concludes that, with some modifications and provisions for new equipment, existing rail and marine systems can provide a transportation base for the intermodal transfer of spent fuel to federal interim storage facilities. Some needed land transportation support and loading and unloading equipment does not currently exist. There are insufficient shipping casks available at this time, but the industrial capability to meet projected needs appears adequate

  15. Spent fuel element storage facility

    Purpose: To always keep water level of a spent fuel cask pit equal with water level of spent fuel storage pool by means of syphon principle. Constitution: The pool water of a spent fuel storage pool is airtightly communicated through a pipe with the pool water of a spent fuel cask, and a gate is provided between the pool and the cask. Since cask is conveyed into the cask pit as the gate close while conveying, the pool water level is raised an amount corresponding to the volume of the cask, and water flow through scattering pipe and the communication pipe to the storage pool. When the fuel is conveyed out of the cask, the water level is lowered in the amount corresponding to the volume in the cask pit, and the water in the pool flow through the communication pipe to the cask pit. (Sekiya, K.)

  16. Intermodal transportation of spent fuel

    Elder, H.K.

    1983-09-01

    Concepts for transportation of spent fuel in rail casks from nuclear power plant sites with no rail service are under consideration by the US Department of Energy in the Commercial Spent Fuel Management program at the Pacific Northwest Laboratory. This report identifies and evaluates three alternative systems for intermodal transfer of spent fuel: heavy-haul truck to rail, barge to rail, and barge to heavy-haul truck. This report concludes that, with some modifications and provisions for new equipment, existing rail and marine systems can provide a transportation base for the intermodal transfer of spent fuel to federal interim storage facilities. Some needed land transportation support and loading and unloading equipment does not currently exist. There are insufficient shipping casks available at this time, but the industrial capability to meet projected needs appears adequate.

  17. Spent fuel management in Canada

    The current status of the Canadian spent fuel storage is presented. This includes wet and dry interim storage. Extension of wet interim storage facilities is nor planned, as dry technologies have found wide acceptance. The Canadian nuclear program is sustained by commercial Ontario Hydro CANDU type reactors, since 1971, representing 13600 MW(e) of installed capacity, able to produce 9200 spent fuel bundles (1800 tU) every year, and Hydro Quebec and New Brunswick CANDU reactors each producing 685 MW(e) and about 100 tU of spent fuel annually. The implementation of various interim (wt and dry) storage technologies resulted in simple, dense and low cost systems. Economical factors determined that the open cycle option be adopted for the CANDU type reactors rather that recycling the spent fuel. Research and development activities for immobilization and final disposal of nuclear waste are being undertaken in the Canadian Nuclear Fuel Waste Management Program

  18. Spent fuel management in Spain

    The spent fuel management strategy in Spain is presented. The strategy includes temporary solutions and plans for final disposal. The need for R and D including partitioning and transmutation, as well as the financial constraints are also addressed. (author)

  19. Iraq spent fuel removal program

    The paper describes the preparation and operations associated with the removal of the 208 spent fuel assemblies from Iraq, with emphasis on the technical challenges that were overcome during this removal process. (author)

  20. SO{sub 2}-ethanol-water fractionation of lignocellulose and pilot scale production of isopropanol-butanol-ethanol solvent mixture with advanced column technology - SEWIBE

    Granstrom, T. [Aalto University, Espoo (Finland)], email: tom.granstrom@aalto.fi

    2012-07-01

    To demonstrate at the pilot scale level the production of biofuels from lignocellulosic biomass using the omnivorous SO{sub 2}- ethanol-water (SEW) fractionation process and advanced column fermentation technology. A monomeric hemicellulose sugar solution will be produced by conditioning the spent fractionation liquor and a glucose solution by subsequent hydrolysis of the liberated cellulosic fibers. The combined monomeric sugars streams containing hexoses and pentoses will be fermented to a mixture of isopropanol, n-butanol and ethanol (IBE solvents) using genetically modified Clostridia bacteria. The recovery yields of the cooking chemicals, i.e. ethanol and unreacted SO{sub 2} from the spent fractionation liquor by evaporation and steam stripping will be established. Soluble and precipitated lignin fractions of the spent liquor combined with the organic residue remaining after solvent-solvent extraction of the IBE solvents will be studied experimentally with the objective to establish processability into commercial products and biofuels, and the total sulphur recovery yield of these biomass fractions.

  1. IAEA spent fuel storage glossary

    The aim of this glossary is to provide a basis for improved international understanding of terms used in the important area of spent fuel storage technology. The glossary is the product of an IAEA Consultant Group with valuable input from a substantial list of reviewers. The glossary emphasizes fuel storage relevant to power reactors, but is also widely applicable to research reactors. The intention is to define terms from current technologies. Terms are limited to those directly related to spent fuel storage

  2. Transportation of spent MTR fuels

    Raisonnier, D.

    1997-08-01

    This paper gives an overview of the various aspects of MTR spent fuel transportation and provides in particular information about the on-going shipment of 4 spent fuel casks to the United States. Transnucleaire is a transport and Engineering Company created in 1963 at the request of the French Atomic Energy Commission. The company followed the growth of the world nuclear industry and has now six subsidiaries and affiliated companies established in countries with major nuclear programs.

  3. Transportation of spent MTR fuels

    This paper gives an overview of the various aspects of MTR spent fuel transportation and provides in particular information about the on-going shipment of 4 spent fuel casks to the United States. Transnucleaire is a transport and Engineering Company created in 1963 at the request of the French Atomic Energy Commission. The company followed the growth of the world nuclear industry and has now six subsidiaries and affiliated companies established in countries with major nuclear programs

  4. Spent-fuel-storage alternatives

    The Spent Fuel Storage Alternatives meeting was a technical forum in which 37 experts from 12 states discussed storage alternatives that are available or are under development. The subject matter was divided into the following five areas: techniques for increasing fuel storage density; dry storage of spent fuel; fuel characterization and conditioning; fuel storage operating experience; and storage and transport economics. Nineteen of the 21 papers which were presented at this meeting are included in this Proceedings. These have been abstracted and indexed

  5. LWR damaged spent fuel transport

    In the weeks following a reactor shut down, spent fuel is checked to control fuel integrity and to identify leaking fuel assemblies. For transport, sound fuel is loaded directly in the cask and defective fuels in special bottles designed by COGEMA and placed into the cask. We will review the main technical aspects of LWR damaged spent fuel transport and COGEMA's experience in this type of transport

  6. HFIR spent fuel management alternatives

    The High Flux Isotope Reactor (HFIR) at Martin Marietta Energy Systems' Oak Ridge National Laboratory (ORNL) has been unable to ship its spent fuel to Savannah River Site (SRS) for reprocessing since 1985. The HFIR storage pools are expected to fill up in the February 1994 to February 1995 time frame. If a management altemative to existing HFIR pool storage is not identified and implemented before the HFIR pools are full, the HFIR will be forced to shut down. This study investigated several alternatives for managing the HFIR spent fuel, attempting to identify options that could be implemented before the HFIR pools are full. The options investigated were: installing a dedicated dry cask storage facility at ORNL, increasing HFIR pool storage capacity by clearing the HFIR pools of debris and either close-packing or stacking the spent fuel elements, storing the spent fuel at another ORNL pool, storing the spent fuel in one or more hot cells at ORNL, and shipping the spent fuel offsite for reprocessing or storage elsewhere

  7. Spent Fuel Management in Slovakia

    The paper describes the SFM system in the Slovak Republic. In 2008, the Slovak Government accepted in its Decision Nr. 328/2008 “The proposal on the strategy of the back-end of the nuclear power engineering”. The state supervision on nuclear safety of SFM is performed by the Nuclear Regulatory Authority of the Slovak Republik (UJD). The legislative framework in the Slovak Republic is based on acts and regulations. In Slovakia there are four nuclear power units in operation. The spent fuel is stored in at-reactor spent fuel storage pools and cooled by water with presence of the boric acid. After certain cooling time, the spent fuel is removed to the Interim Spent Fuel Storage Facility (ISFSF). For the spent fuel transport transportation container C-30 is used. UJD steers various research tasks under the Research & Development program (R&D). Several years ago we started process of burnup credit (BUC) implementation in Slovakia for VVER-440 reactors. Another R&D project is focused on determination of the relation between the spent fuel residual heat generation and surface temperature of the transport container C-30. By the end of 2009 first two modules — visual inspection and gamma spectroscopy — of inspection stand SVYP-440 at ISFSF were put into operation. (author)

  8. Energy and Environmental Performance of Bioethanol from Different Lignocelluloses

    Gjalt Huppes

    2010-01-01

    Full Text Available Climate change and the wish to reduce the dependence on oil are the incentives for the development of alternative energy sources. The use of lignocellulosic biomass together with cellulosic processing technology provides opportunities to produce fuel ethanol with less competition with food and nature. Many studies on energy analysis and life cycle assessment of second-generation bioethanol have been conducted. However, due to the different methodology used and different system boundary definition, it is difficult to compare their results. To permit a direct comparison of fuel ethanol from different lignocelluloses in terms of energy use and environmental impact, seven studies conducted in our group were summarized in this paper, where the same technologies were used to convert biomass to ethanol, the same system boundaries were defined, and the same allocation procedures were followed. A complete set of environmental impacts ranging from global warming potential to toxicity aspects is used. The results provide an overview on the energy efficiency and environmental performance of using fuel ethanol derived from different feedstocks in comparison with gasoline.

  9. Lignocellulose degradation by the isolate of Streptomyces griseorubens JSD-1.

    Feng, Haiwei; Sun, Yujing; Zhi, Yuee; Mao, Liang; Luo, Yanqing; Wei, Xing; Zhou, Pei

    2015-03-01

    Streptomyces griseorubens JSD-1 is an isolate that can utilize lignocellulose (straw) as its sole carbon source for growth, and these lignocellulolytic genes involved in this biotransformation are expected to be crucial. However, little is known about the genetic basis related to this process. To further investigate the lignocellulose-degrading mechanisms, genome sequencing was carried out using MiSeq platform. After obtaining its draft genome, the key lignocellulolytic genes such as multicopper oxidase, exo-1, 4-β-glucanase, endo-1,4-β-glucanase, and β-xylosidase were identified and characterized. Multiple sequence alignments were performed to find out the identities of these analyzed proteins to those of their similar species. Signal peptide cleavage sites were predicted by SignalP 4.1 to reflect the cellular localization of their mature proteins. Besides, predicted 3D structures of these proteins were modeled by Phyre2, which showed to be highly identical to the templates in the PDB database. Finally, quantitative real-time PCR revealed that expression levels of all analyzed enzymes were significantly and generally up-regulated during the whole cultivation, indicating that they all contributed to the biodegradation. PMID:25452226

  10. Ethanol Production from Lignocellulose by the Dimorphic Fungus Mucor Indicus

    Lennartsson, P.R.; Taherzadeh, M.J. (School of Engineering, Univ. of Boraas, SE-50190, Boraas (Sweden)). e-mail: Patrik.Lennartsson@hb.se; Karimi, K. (Dept. of Chemical Engineering, Isfahan Univ. of Technology, 84156-83111, Isfahan (IR)); Edebo, L. (Dept. of Clinical Bacteriology, Univ. of Goeteborg, SE-41346, Goeteborg (Sweden))

    2008-10-15

    Ethanol production from dilute-acid lignocellulosic hydrolyzate by the dimorphic fungus Mucor indicus was investigated. A mixture of different forest wood chips dominated by spruce was hydrolyzed with 0.5 g/L sulfuric acid at 15 bar for 10 min, yielding different sugars including galactose, glucose, mannose, and xylose, but also different fermentation inhibitors such as acetic acid, furfural, hydroxymethyl furfural (HMF), and phenolic compounds. We induced different morphological growth of M. indicus from purely filamentous, mostly filamentous, mostly yeast-like to purely yeast-like. The different forms were then used to ferment the hydrolyzate. They tolerated the presence of the inhibitors under anaerobic batch cultivation well and the ethanol yield was 430-440 g/kg consumed sugars. The ethanol productivity depended on the morphology. Judging from these results, we conclude that M. indicus, is useful for ethanol production from toxic substrates independent of its morphology. Keywords: bio-ethanol, lignocellulosic materials, dilute acid hydrolysis, Mucor indicus, dimorphic fungi

  11. A method for rapid determination of sugars in lignocellulose prehydrolyzate

    Congcong Chi

    2013-02-01

    Full Text Available A simple and rapid dual-wavelength spectroscopic method is used for simultaneous determination of pentoses and hexoses in the prehydrolyzate from lignocellulosic biomass. The method is based on the following reaction mechanism: in the solution of hydrochloric acid, phloroglucinol gives color reaction with sugars or their degradation products, showing maximum absorbance at 553 nm and 410 nm. Based on dual-wavelength spectrophotometric measurement, the pentoses and hexoses can separately be quantified. It was found that the derivatives from these two different sugars have an isosbestic point at 425 nm. According to the validation results, high accuracy and reasonable recovery rate is shown with the present method (pentoses recovery 97.1 to 100.0%, hexoses recovery 97.2 to 102.0%. Additionally, the interferences from substances including lignin, furfural, 5-hydroxymethyl furfural (HMF, glucuronic acid, and galacturonic acid are insignificant. All of the above results illustrate the suitability of this method for analyzing sugars in the lignocelluloses prehydrolyzate, especially hardwoods or herbaceous plants, based on forest-related biorefinery research.

  12. The potential of lignocellulosic ethanol production in the Mediterranean Basin

    Faraco, Vincenza [Department of Organic Chemistry and Biochemistry, University of Naples ' ' Federico II' ' , Naples (Italy); School of Biotechnological Sciences, University of Naples ' ' Federico II' ' , Naples (Italy); Hadar, Yitzhak [Department of Microbiology and Plant Pathology, The Robert H. Smith Faculty of Agriculture, Food and Environment, Hebrew University of Jerusalem, Rehovot (Israel)

    2011-01-15

    This review provides an overview of the potential of bioethanol fuel production from lignocellulosic residues in the Mediterranean Basin. Residues from cereal crops, olive trees, and tomato and grape processing are abundant lignocellulosic wastes in France, Italy, Spain, Turkey and Egypt, where their use as raw materials for ethanol production could give rise to a potential production capacity of 13 Mtoe of ethanol. Due to the lack of sufficient amounts of agricultural residues in all of the other Mediterranean countries, use of the cellulosic content of municipal solid waste (MSW) as feedstock for ethanol fuel production is also proposed. A maximum potential production capacity of 30 Mtoe of ethanol could be achieved from 50% of the 180 million tons of waste currently produced annually in the Mediterranean Basin, the management of which has become a subject of serious concern. However, to make large-scale ethanol production from agricultural residues and MSW a medium-term feasible goal in the Mediterranean Basin, huge efforts are needed to achieve the required progress in cellulose ethanol technologies and to overcome several foreseeable constraints. (author)

  13. Development of a Commerical Enzyme System for Lignocellulosic Biomass Saccharification

    Manoj Kumar, PhD

    2011-02-14

    Lignocellulosic biomass is the most abundant, least expensive renewable natural biological resource for the production of biobased products and bioenergy is important for the sustainable development of human civilization in 21st century. For making the fermentable sugars from lignocellulosic biomass, a reduction in cellulase production cost, an improvement in cellulase performance, and an increase in sugar yields are all vital to reduce the processing costs of biorefineries. Improvements in specific cellulase activities for non-complexed cellulase mixtures can be implemented through cellulase engineering based on rational design or directed evolution for each cellulase component enzyme, as well as on the reconstitution of cellulase components. In this paper, we will provide DSM's efforts in cellulase research and developments and focus on limitations. Cellulase improvement strategies based on directed evolution using screening on relevant substrates, screening for higher thermal tolerance based on activity screening approaches such as continuous culture using insoluble cellulosic substrates as a powerful selection tool for enriching beneficial cellulase mutants from the large library. We will illustrate why and how thermostable cellulases are vital for economic delivery of bioproducts from cellulosic biomass using biochemical conversion approach.

  14. High throughput determination of glucan and xylan fractions in lignocelluloses.

    Selig, Michael J; Tucker, Melvin P; Law, Cody; Doeppke, Crissa; Himmel, Michael E; Decker, Stephen R

    2011-05-01

    The analysis of structural glucan and xylan in lignocellulose was scaled down from original two-stage sulfuric acid hydrolysis methods (Moore WE and Johnson DB 1967 Procedures for the chemical analysis of wood and wood products. U.S. Forest Products Laboratory, U.S. Department of Agriculture., Madison, WI) and integrated into a recently-developed, high throughput pretreatment and enzymatic saccharification system. Novel 96×1.8 ml-well Hastelloy reactor plates (128×86×51 mm) based on previously described 96-well pretreatment reactor plates were paired with custom aluminum filler plates (128×86×18 mm) for use in Symyx Powdernium solids dispensing systems. The incorporation of glucose oxidase and xylose dehydrogenase linked assays to speed post-hydrolysis sugar analysis dramatically reduced the time for analysis of large lignocellulosic sample sets. The current system permits the determination of the glucan and xylan content of 96 replicates (per reactor plate) in under 6 h and parallel plate processing increases the analysis throughput substantially. PMID:21287235

  15. Compounds inhibiting the bioconversion of hydrothermally pretreated lignocellulose.

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

    2015-05-01

    Hydrothermal pretreatment using liquid hot water, steam explosion, or dilute acids enhances the enzymatic digestibility of cellulose by altering the chemical and/or physical structures of lignocellulosic biomass. However, compounds that inhibit both enzymes and microbial activity, including lignin-derived phenolics, soluble sugars, furan aldehydes, and weak acids, are also generated during pretreatment. Insoluble lignin, which predominantly remains within the pretreated solids, also acts as a significant inhibitor of cellulases during hydrolysis of cellulose. Exposed lignin, which is modified to be more recalcitrant to enzymes during pretreatment, adsorbs cellulase nonproductively and reduces the availability of active cellulase for hydrolysis of cellulose. Similarly, lignin-derived phenolics inhibit or deactivate cellulase and β-glucosidase via irreversible binding or precipitation. Meanwhile, the performance of fermenting microorganisms is negatively affected by phenolics, sugar degradation products, and weak acids. This review describes the current knowledge regarding the contributions of inhibitors present in whole pretreatment slurries to the enzymatic hydrolysis of cellulose and fermentation. Furthermore, we discuss various biological strategies to mitigate the effects of these inhibitors on enzymatic and microbial activity to improve the lignocellulose-to-biofuel process robustness. While the inhibitory effect of lignin on enzymes can be relieved through the use of lignin blockers and by genetically engineering the structure of lignin or of cellulase itself, soluble inhibitors, including phenolics, furan aldehydes, and weak acids, can be detoxified by microorganisms or laccase. PMID:25904131

  16. Screening of ligninolytic fungi for biological pretreatment of lignocellulosic biomass.

    Xu, Chunyan; Singh, Deepak; Dorgan, Kathleen M; Zhang, Xiaoyu; Chen, Shulin

    2015-10-01

    To identify white rot fungi with high potential in biological pretreatment of lignocellulosic biomass, preliminary screening was carried out on plates by testing different strains for their ability to oxidize guaiacol and decolorize the dyes azure B and Poly R-478. Of the 86 strains screened, 16 were selected for secondary screening for their ligninolytic ability; however, low manganese peroxidase activity and no lignin peroxidase activity were detected. Strain BBEL0970 proved to be the most efficient in laccase production and was subsequently identified as Trametes versicolor by analysis of the ribosomal DNA internal transcribed spacer gene sequence. In combining laccase production with biological pretreatment, the replacement of glucose with barley straw significantly improved the laccase activity by up to 10.3 U/mL, which provided evidence toward potential utilization of barley straw in laccase production by BBEL0970. Simultaneously, comparison by thermogravimetric analysis of the untreated and pretreated barley straw in liquid fermentation of laccase also demonstrated the high potential of BBEL0970 in biological pretreatment of lignocellulosic biomass. This work sheds light on further exploration on the integrated process of low-cost laccase production and efficient biological pretreatment of barley straw by T. versicolor BBEL0970. PMID:26286682

  17. Spent Nuclear Fuel project, project management plan

    Fuquay, B.J.

    1995-10-25

    The Hanford Spent Nuclear Fuel Project has been established to safely store spent nuclear fuel at the Hanford Site. This Project Management Plan sets forth the management basis for the Spent Nuclear Fuel Project. The plan applies to all fabrication and construction projects, operation of the Spent Nuclear Fuel Project facilities, and necessary engineering and management functions within the scope of the project

  18. Spent Nuclear Fuel project, project management plan

    The Hanford Spent Nuclear Fuel Project has been established to safely store spent nuclear fuel at the Hanford Site. This Project Management Plan sets forth the management basis for the Spent Nuclear Fuel Project. The plan applies to all fabrication and construction projects, operation of the Spent Nuclear Fuel Project facilities, and necessary engineering and management functions within the scope of the project

  19. Towards an Understanding of How Protein Hydrolysates Stimulate More Efficient Biosynthesis in Cultured Cells

    Siemensma, André; Babcock, James; Wilcox, Chris; Huttinga, Hans

    In the light of the growing demand for high quality plant-derived hydrolysates (i.e., HyPep™ and UltraPep™ series), Sheffield Bio-Science has developed a new hydrolysate platform that addresses the need for animal-free cell culture medium supplements while also minimizing variability concerns. The platform is based upon a novel approach to enzymatic digestion and more refined processing. At the heart of the platform is a rationally designed animal component-free (ACF) enzyme cocktail that includes both proteases and non-proteolytic enzymes (hydrolases) whose activities can also liberate primary components of the polymerized non-protein portion of the raw material. This enzyme system is added during a highly optimized process step that targets specific enzyme-substrate reactions to expand the range of beneficial nutritional factors made available to cells in culture. Such factors are fundamental to improving the bio-performance of the culture system, as they provide not merely growth-promoting peptides and amino acids, but also key carbohydrates, lipids, minerals, and vitamins that improve both rate and quality of protein expression, and serve to improve culture life due to osmo-protectant and anti-apoptotic properties. Also of significant note is that, compared to typical hydrolysates, the production process is greatly reduced and requires fewer steps, intrinsically yielding a better-controlled and therefore more reproducible product. Finally, the more sophisticated approach to enzymatic digestion renders hydrolysates more amenable to sterile filtration, allowing hydrolysate end users to experience streamlined media preparation and bioreactor supplementation activities. Current and future development activities will evolve from a better understanding of the complex interactions within a handful of key biochemical pathways that impact the growth and productivity of industrially relevant organisms. Presented in this chapter are some examples of the efforts that have been made so far to elucidate the mechanisms for the often dramatic benefits that hydrolysates can impart on cell culture processes. Given the variety of roles that hydrolysates likely play in each cell type, close collaboration between protein hydrolysate manufacturers and biopharmaceutical developers will continue to be critical to expanding the industry's knowledge and retaining hydrolysates as a tool for enhancing media formulations.

  20. Combustion of spent shale in fluidized bed

    Large amounts of spent shale are produced during oil production from oil shale. This spent shale has a caloric value of about 1100 kCal/kg and could be used as a low grade fuel for energy production. Up to now the spent shale has not been used. The first steps towards the use of spent shale were taken by Raul Uuesoo in the fifties. He investigated the combustion of spent shale in a fluidized bed, adapted combustion theory for spent shale particles and provided the foundation for calculations for spent shale furnaces. A part of his investigations are reported in short form in this article

  1. Affinity purification of copper-chelating peptides from sunflower protein hydrolysates.

    Megías, Cristina; Pedroche, Justo; Yust, Maria M; Girón-Calle, Julio; Alaiz, Manuel; Millan, Francisco; Vioque, Javier

    2007-08-01

    Copper-chelating peptides were purified from sunflower protein hydrolysates by affinity chromatography using immobilized copper. A variety of protein hydrolysates were obtained by incubation with the proteases Alcalase and Flavourzyme for different periods of time. Chelating activity was indirectly determined by measuring the inhibitory effect of hydrolysates on the oxidation of beta-carotene by copper. Copper-binding peptides purified from the two hydrolysates that inhibited oxidation by copper the most contained 25.4 and 42.0% histidine and inhibited beta-carotene oxidation 8 and 3 times more than the original hydrolysates, which had 2.4 and 2.6% histidine, respectively. Thus, histidine content is not the only factor involved in antioxidant activity, and probably other factors such as peptide size and amino acid sequence are also important. This work shows that affinity chromatography can be used for the purification of copper-chelating peptides and probably other metals of nutritional interest such as calcium, iron, and zinc. In addition to their antioxidant potential, chelating peptides are of nutritional interest because they increase bioavailability of minerals. PMID:17636941

  2. Chickpea protein hydrolysate as a substitute for serum in cell culture.

    Girón-Calle, Julio; Vioque, Javier; Pedroche, Justo; Alaiz, Manuel; Yust, María M; Megías, Cristina; Millán, Francisco

    2008-07-01

    The growth of mammalian cells in vitro requires the use of rich culture media that are prepared by combining serum with specific nutrient formulations. Serum, the most expensive component of culture media, provides a complex mixture of growth factors and nutrients. Protein hydrolysates that can support in vitro cell growth and eliminate or reduce the need to use serum have been obtained from different sources. Here we describe the use of two food grade proteases to produce a chickpea protein hydrolysate that has been added to cell culture medium in order to determine whether it can be used as a substitute for serum. Medium containing the hydrolysate has been tested using two human cells lines: the monocytic THP-1 cell line which grows in suspension, and the epithelial Caco-2 cell line which grows as a monolayer. The chickpea protein hydrolysate was a good substitute for serum in the first case, but did not allow growth of Caco-2 cells. Supplementation of culture media with this inexpensive and safe hydrolysate would greatly reduce the cost of cell culture. PMID:19003183

  3. Amino acid composition and functional properties of giant red sea cucumber ( Parastichopus californicus) collagen hydrolysates

    Liu, Zunying; Su, Yicheng; Zeng, Mingyong

    2011-03-01

    Giant red sea cucumber ( Parastichopus californicus) is an under-utilized species due to its high tendency to autolysis. The aim of this study was to evaluate the functional properties of collagen hydrolysates from this species. The degree of hydrolysis (DH), amino acid composition, SDS-PAGE, emulsion activity index (EAI), emulsion stability index (ESI), foam expansion (FE), and foam stability (FS) of hydrolysates were investigated. The effects of pH on the EAI, ESI FE and FS of hydrolysates were also investigated. The results indicated that the β and α 1 chains of the collagen were effectively hydrolyzed by trypsin at 50°c with an Enzyme/Substrate (E/S) ration of 1:20 (w:w). The DH of collagen was up to 17.3% after 3 h hydrolysis with trypsin. The hydrolysates had a molecular weight distribution of 1.1-17 kDa, and were abundant in glycine (Gly), proline (Pro), glutamic acid (Glu), alanine (Ala) and hydroxyproline (Hyp) residues. The hydrolysates were fractionated into three fractions ( 10 kDa), and the fraction of 3-10 kDa exhibited a higher EAI value than the fraction of > 10 kDa ( P 10 kDa had higher FE and FS values than other fractions ( P 10 kDa showed higher FE value, respectively. They are hoped to be utilized as functional ingredients in food and nutraceutical industries.

  4. Isolation and Characterization of a Nitrile-Hydrolysing Bacterium Isoptericola variabilis RGT01.

    Kaur, Gurdeep; Soni, Pankaj; Tewari, Rupinder; Sharma, Rohit

    2014-06-01

    A nitrile-hydrolysing bacterium, identified as Isoptericola variabilis RGT01, was isolated from industrial effluent through enrichment culture technique using acrylonitrile as the carbon source. Whole cells of this microorganism exhibited a broad range of nitrile-hydrolysing activity as they hydrolysed five aliphatic nitriles (acetonitrile, acrylonitrile, propionitrile, butyronitrile and valeronitrile), two aromatic nitriles (benzonitrile and m-Tolunitrile) and two arylacetonitriles (4-Methoxyphenyl acetonitrile and phenoxyacetonitrile). The nitrile-hydrolysing activity was inducible in nature and acetonitrile proved to be the most efficient inducer. Minimal salt medium supplemented with 50 mM acetonitrile, an incubation temperature of 30 °C with 2 % v/v inoculum, at 200 rpm and incubation of 48 h were found to be the optimal conditions for maximum production (2.64 ± 0.12 U/mg) of nitrile-hydrolysing activity. This activity was stable at 30 °C as it retained around 86 % activity after 4 h at this temperature, but was thermolabile with a half-life of 120 min and 45 min at 40 °C and 50 °C respectively. PMID:25320428

  5. Characterisation of hydrolysates prepared from engraved catfish (Nemapteryx caelata) roe by serial hydrolysis.

    Binsi, P K; Viji, P; Panda, Satyen Kumar; Mathew, Suseela; Zynudheen, A A; Ravishankar, C N

    2016-01-01

    Protein hydrolysates were prepared from defatted engraved catfish roe using alcalase enzyme by a two-stage serial hydrolysis process. The soluble hydrolysate formed after first stage of hydrolysis was removed (RH-1) and fresh enzyme was added at the same concentration to achieve further hydrolysis (RH-2). Further, compositional, surface-active and antioxidant properties of both hydrolysates were compared. The SDS-PAGE profile showed two distinct bands for RH-1, whereas no bands were visible for RH-2. On the other hand, gel filtration chromatography of the hydrolysates indicated 3-4 distinct fractions. Both the hydrolysates showed similar foam forming abilities, however, RH-1 exhibited poor foam stability. Emulsion properties of RH-1 were superior to that of RH-2. The major fractions eluted through gel filtration column were screened for antioxidant properties. Higher DPPH radical scavenging and metal chelating properties were observed for RH-1second fragment, whereas FRAP and Fe(2+) reducing power was highest for second fragment of RH-2. PMID:26787939

  6. Antioxidant activities of bambara groundnut (Vigna subterranea) protein hydrolysates and their membrane ultrafiltration fractions.

    Arise, Abimbola K; Alashi, Adeola M; Nwachukwu, Ifeanyi D; Ijabadeniyi, Oluwatosin A; Aluko, Rotimi E; Amonsou, Eric O

    2016-05-18

    In this study, the bambara protein isolate (BPI) was digested with three proteases (alcalase, trypsin and pepsin), to produce bambara protein hydrolysates (BPHs). These hydrolysates were passed through ultrafiltration membranes to obtain peptide fractions of different sizes (3 kDa. This is in agreement with the result obtained for the ferric reducing power, metal chelating and hydroxyl radical scavenging activities where higher molecular weight peptides exhibited better activity (p DPPH) radical scavengers but not superoxide radicals when compared to the bigger peptides. In comparison with glutathione (GSH), BPHs and their membrane fractions had better (p < 0.05) reducing power and ability to chelate metal ions except for the pepsin hydrolysate and its membrane fractions that did not show any metal chelating activity. However, the 5-10 kDa pepsin hydrolysate peptide fractions had greater (88%) hydroxyl scavenging activity than GSH, alcalase and trypsin hydrolysates (82%). These findings show the potential use of BPHs and their peptide fraction as antioxidants in reducing food spoilage or management of oxidative stress-related metabolic disorders. PMID:27156453

  7. Comparison of immunomodulating properties of Beta-lactoglobulin and its hydrolysates.

    Cui-cui Duan

    2014-02-01

    Full Text Available Cow's milk allergy is one of the most common food allergies in childhood. Beta-lactoglobulin (β- lg is a dominant allergen in cow's milk. Hydrolysis is known as an effective method to reduce the allergenicity of proteins. Thus, the objective of this study was to compare the allergenicity of β-lg and its hydrolysates using an animal model. Twenty four BALB/c mice were divided into three groups and subcutaneously injected with native bovine β-lg and its hydrolysates on days 0, 7 and 14. During the sensitization period, a number of systemic anaphylactic indicators were observed in mice sensitized by β-lg compared to those sensitized by hydrolysates of β-lg. Mice sensitized by hydrolysates of β-lg showed a significantly lower spleen lymphocyte proliferation level than that sensitized by intact β-lg. Antibody levels of β-lg-specific IgE in serum induced by native β-lg were significantly high. Plasma histamine levels were also evaluated and showed the same trend as IgE. Moreover, the hydrolysates of β-lg significantly down-regulated IL-4 and IL-5 secretions in serum. These results suggested that enzymatic hydrolysis could reduce the allergenicity of β-lg.

  8. Aggregation properties of whey protein hydrolysates generated with Bacillus licheniformis proteinase activities.

    Spellman, David; Kenny, Patricia; O'Cuinn, Gerard; FitzGerald, Richard J

    2005-02-23

    Hydrolysis of whey protein concentrate (WPC) with Alcalase 2.4 L, a Bacillus licheniformis proteinase preparation, induces gelation. The aggregation behavior of WPC hydrolysates generated with Alcalase and Prolyve 1000, a Bacillus licheniformis proteinase that did not induce gelation, were studied by turbidity and particle size analysis. With the use of synthetic peptide substrates, it was shown that Alcalase contains a glutamyl endopeptidase (GE) activity not present in Prolyve. Comparison of the aggregation behavior of WPC hydrolysates generated with Alcalase, Prolyve, and combinations of Prolyve with a GE activity isolated from Alcalase showed that GE was responsible for the observed enzyme-induced peptide aggregation in Alcalase hydrolysates. Hydrolysates generated with Prolyve, having a degree of hydrolysis (DH) of 11.8% and 10.4% of peptide material greater than 10 kDa, could be induced to aggregate by the addition of GE. These results emphasize the contribution of enzyme specificity to the physicochemical and functional characteristics of proteinase hydrolysates of WPC. PMID:15713050

  9. Whey Protein Concentrate Hydrolysate Prevents Bone Loss in Ovariectomized Rats.

    Kim, Jonggun; Kim, Hyung Kwan; Kim, Saehun; Imm, Ji-Young; Whang, Kwang-Youn

    2015-12-01

    Milk is known as a safe food and contains easily absorbable minerals and proteins, including whey protein, which has demonstrated antiosteoporotic effects on ovariectomized rats. This study evaluated the antiosteoporotic effect of whey protein concentrate hydrolysate (WPCH) digested with fungal protease and whey protein concentrate (WPC). Two experiments were conducted to determine (1) efficacy of WPCH and WPC and (2) dose-dependent impact of WPCH in ovariectomized rats (10 weeks old). In Experiment I, ovariectomized rats (n=45) were allotted into three dietary treatments of 10 g/kg diet of WPC, 10 g/kg diet of WPCH, and a control diet. In Experiment II, ovariectomized rats (n=60) were fed four different diets (0, 10, 20, and 40 g/kg of WPCH). In both experiments, sham-operated rats (n=15) were also fed a control diet containing the same amount of amino acids and minerals as dietary treatments. After 6 weeks, dietary WPCH prevented loss of bone, physical properties, mineral density, and mineral content, and improved breaking strength of femurs, with similar effect to WPC. The bone resorption enzyme activity (tartrate resistance acid phosphatase) in tibia epiphysis decreased in response to WPCH supplementation, while bone formation enzyme activity (alkaline phosphatase) was unaffected by ovariectomy and dietary treatment. Bone properties and strength increased as the dietary WPCH level increased (10 and 20 g/kg), but there was no difference between the 20 and 40 g/kg treatment. WPCH and WPC supplementation ameliorated bone loss induced by ovariectomy in rats. PMID:26367331

  10. Biotechnological conversion of spent coffee grounds into polyhydroxyalkanoates and carotenoids.

    Obruca, Stanislav; Benesova, Pavla; Kucera, Dan; Petrik, Sinisa; Marova, Ivana

    2015-12-25

    Coffee is one of the world's most popular beverages and has been growing steadily in commercial importance. Nowadays, coffee is the second largest traded commodity in the world, after petroleum. Hence, coffee industry is responsible for the generation of large amounts of waste, especially spent coffee grounds (SCG). Various attempts to valorize this waste stream of coffee industry were made. This article summarizes our research and publications aiming at the conversion of SCG into valuable products - polyhydroxyalkanoates (PHAs) and carotenoids. At first, oil extracted from SCG (approx. 15 wt% oil in SCG) can be efficiently (YP/S=0.82 g/g) converted into PHA employing Cupriavidus necator H16. Further, the solid residues after oil extraction can be hydrolyzed (by the combination of chemical and enzymatic hydrolysis) yielding fermentable sugars, which can be further used as a substrate for the production of PHAs employing Bacillus megaterium (YP/S=0.04 g/g) or Burkholderia cepacia (YP/S=0.24 g/g). Alternatively, SCG hydrolysate can be used as a substrate for biotechnological production of carotenoids by carotenogenic yeast Sporobolomyces roseus. Solid residues after either oil extraction or hydrolysis can be used as fuel in industrial boilers to generate heat and energy. Therefore, entire biomass of SCG can be used for sustainable production of PHAs and/or carotenoids employing bio-refinery approach. PMID:25721970

  11. Revisiting the structural features of arabinoxylans from brewers' spent grain.

    Coelho, Elisabete; Rocha, M Angélica M; Moreira, Ana S P; Domingues, M Rosário M; Coimbra, Manuel A

    2016-03-30

    The brewers' spent grain (BSG) arabinoxylans (AX) have been described to be composed by a backbone of (β1→4)-linked xylose residues containing only single units of arabinose as side chains. However, this is not in accordance with the structural features of AX from other cereal sources. Aiming to disclose the possibility of additional structural details, fractions enriched in AX were obtained by sequential extraction from BSG. The AX richest fraction was hydrolysed with xylanase, fractioned by size-exclusion chromatography, and analysed by electrospray tandem mass spectrometry (ESI-MS(n)). Methylation analysis showed that the amount of terminally linked arabinose residues was not in accordance with the number of xylose branching points. This was due to the presence of O-acetyl, hexose, hexuronic acid, and methylated uronic acid residues. AXs presenting these structural features can be a potential source of a large screening prebiotic, providing, in the same molecule, areas of fast and slow probiotic fermentation rates. PMID:26794960

  12. Development of spent fuel remote handling technology

    Since the nation's policy on spent fuel management is not finalized, the technical items commonly required for safe management and recycling of spent fuel - remote technologies of transportation, inspection, maintenance, and disassembly of spent fuel - are selected and pursued. In this regards, the following R and D activities are carried out : collision free transportation of spent fuel assembly, mechanical disassembly of spent nuclear fuel and graphical simulation of fuel handling / disassembly process. (author). 36 refs., 16 tabs., 77 figs

  13. Development of spent fuel remote handling technology

    Yoon, Ji Sup; Park, B. S.; Park, Y. S.; Oh, S. C.; Kim, S. H.; Cho, M. W.; Hong, D. H

    1997-12-01

    Since the nation`s policy on spent fuel management is not finalized, the technical items commonly required for safe management and recycling of spent fuel - remote technologies of transportation, inspection, maintenance, and disassembly of spent fuel - are selected and pursued. In this regards, the following R and D activities are carried out : collision free transportation of spent fuel assembly, mechanical disassembly of spent nuclear fuel and graphical simulation of fuel handling / disassembly process. (author). 36 refs., 16 tabs., 77 figs

  14. Conversion of lignocellulosic biomass by irradiation: use of high-performance liquid chromatography for study

    Irradiation of lignocellulosic material is under investigation as one means of converting biomass to useful chemical feedstocks and/or fermentable substrates. High-energy gamma radiation in combination with various chemical treatments effects degradation of lignocellulosic and cellulosic materials. The composition of the generated products has been monitored for carbohydrates and organic acids by high-performance liquid chromatography (HPLC). Comparisons of the extent and products of decomposition of the cellulose component of the lignocellulosic materials are presented. 15 references, 6 figures, 2 tables

  15. Enzymatic hydrolysis of ovomucin and the functional and structural characteristics of peptides in the hydrolysates.

    Abeyrathne, E D N S; Lee, H Y; Jo, C; Suh, J W; Ahn, D U

    2016-02-01

    Ovomucin was hydrolyzed using enzymes or by heating under alkaline conditions (pH 12.0), and the functional, structural and compositional characteristics of the peptides in the hydrolysates were determined. Among the treatments, heating at 100 °C for 15 min under alkaline conditions (OM) produced peptides with the highest iron-binding and antioxidant capacities. Ovomucin hydrolyzed with papain (OMPa) or alcalase (OMAl) produced peptides with high ACE-inhibitory activity. The mass spectrometry analysis indicated that most of the peptides from OMPa were 2 kDa. OMAl hydrolyzed ovomucin almost completely and no peptides within 700-5000 Da were found in the hydrolasate. The results indicated that the number and size of peptides were closely related to the functionality of the hydrolysates. Considering the time, cost and activities of the hydrolysates, OM was the best treatment for hydrolyzing ovomucin to produce functional peptides. PMID:26304326

  16. Changes in vascularization of internal organs in rabbits with experimental atherosclerosis, treated with protein hydrolysate

    The vascularization of the internal organs of rabbits with experimental atherosclerosis was studied by the method of Sapirstein with 86 rubidium. Experiments were carried out on male Chinchilla rabbits, fed cholesterol in a dose of 0,2 g/kg of body weight daily for a period of 90 days. Part of the animals were treated with protein hydrolysate in a dose of 5 ml/kg of body weight subcutaneously and the remaining - with physiologic saline. There was reduced vascularization in the heart, kidneys, intestines, liver, adrenals, pancreas and other internal organs in rabbits fed cholestrol and treated with physiologic saline. Administration of protein hydrolysate had protective effect on organ vascularization. Accumulation of 86 rubidium in a large part of the animals was greater than in control group. It is shown that protein hydrolysate amino acids stabilize the endothelial cells and stimulate the local vascularization. (author)

  17. The application of thrombectomy with hydrolyser catheter in the treatment of lower extremity deep venous thrombosis

    Objective: To evaluate the clinical effectiveness of thrombectomy with hydrolyser catheter combined with catheter-directed thrombolysis in the treatment of chronic lower extremity deep venous thrombosis (LEDVT). Methods: 15 patients with thrombosis in left iliac veins (n = 2), left iliac and femoral veins (n = 8 ), left and right iliac and femoral veins (n = 5). Inferior vena cava filters (LVCF) were placed in all patients via the normal femoral veins. Antegrade puncture and catheterization was carried out through the femoral veins or popliteal veins in the thrombotic side. Thrombus aspiration with hydrolyser catheter combined with intravascular thrombolysis was accomplished. Results: The success rate of percutaneous catheterization was 100% (15/15). Total effective rate was 93% (14/15). No serious complications were observed. Conclusion: Thrombectomy with hydrolyser catheter combined with catheter-directed thrombolysis in the treatments of LEDVT is safe and effective

  18. Fish protein hydrolysates: proximate composition, amino acid composition, antioxidant activities and applications: a review.

    Chalamaiah, M; Dinesh Kumar, B; Hemalatha, R; Jyothirmayi, T

    2012-12-15

    The fish processing industry produces more than 60% by-products as waste, which includes skin, head, viscera, trimmings, liver, frames, bones, and roes. These by-product wastes contain good amount of protein rich material that are normally processed into low market-value products, such as animal feed, fish meal and fertilizer. In view of utilizing these fish industry wastes, and for increasing the value to several underutilised fish species, protein hydrolysates from fish proteins are being prepared by several researchers all over the world. Fish protein hydrolysates are breakdown products of enzymatic conversion of fish proteins into smaller peptides, which normally contain 2-20 amino acids. In recent years, fish protein hydrolysates have attracted much attention of food biotechnologists due to the availability of large quantities of raw material for the process, and presence of high protein content with good amino acid balance and bioactive peptides (antioxidant, antihypertensive, immunomodulatory and antimicrobial peptides). PMID:22980905

  19. 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.

  20. Preparation of squid skin collagen hydrolysate as an antihyaluronidase, antityrosinase, and antioxidant agent.

    Nakchum, Ladawan; Kim, Sang Moo

    2016-02-17

    A collagen was isolated from squid skin, a processing waste product. The biofunctional activities of enzymatic squid skin collagen hydrolysates were determined to produce a value-added material. Five low-molecular-mass hydrolysate fractions, F1 (>30 kD), F2 (10-30 kD), F3 (3-10 kD), F4 (1-3 kD), and F5 (tyrosinase activity by 39.65% at 1 mg/mL. Furthermore, F3 had stronger hydroxyl radical scavenging activity (IC50 = 149.94 µg/mL) than ascorbic acid (IC50 = 212.94 µg/mL). Therefore, the squid collagen hydrolysate can be utilized as a nutraceutical or cosmeceutical agent. PMID:25568978

  1. Antioxidant activity and angiotensin I-converting enzyme inhibition by enzymatic hydrolysates from bee bread.

    Nagai, Takeshi; Nagashima, Toshio; Suzuki, Nobutaka; Inoue, Reiji

    2005-01-01

    Enzymatic hydrolysates were prepared from bee bread using three proteases. The antioxidant properties of these hydrolysates were measured using four different methods. These had remarkable antioxidant activity similar or superior to that of 1 mM alpha-tocopherol. They also had high scavenging activities against active oxygen species as the superoxide anion radical and hydroxyl radicals. Moreover, they showed angiotensin I-converting enzyme inhibitory activities and the activities were similar to those from various fermented foods such as fish sauce, sake, vinegar, cheese, miso, and natto. The present studies reveal that enzymatic hydrolysates from bee bread are of benefit not only for the materials of health food diets, but also for in patients undergoing various diseases such as cancer, cardiovascular diseases, diabetes, and hypertension. PMID:15787258

  2. High-throughput Saccharification assay for lignocellulosic materials.

    Gomez, Leonardo D; Whitehead, Caragh; Roberts, Philip; McQueen-Mason, Simon J

    2011-01-01

    Polysaccharides that make up plant lignocellulosic biomass can be broken down to produce a range of sugars that subsequently can be used in establishing a biorefinery. These raw materials would constitute a new industrial platform, which is both sustainable and carbon neutral, to replace the current dependency on fossil fuel. The recalcitrance to deconstruction observed in lignocellulosic materials is produced by several intrinsic properties of plant cell walls. Crystalline cellulose is embedded in matrix polysaccharides such as xylans and arabinoxylans, and the whole structure is encased by the phenolic polymer lignin, that is also difficult to digest (1). In order to improve the digestibility of plant materials we need to discover the main bottlenecks for the saccharification of cell walls and also screen mutant and breeding populations to evaluate the variability in saccharification (2). These tasks require a high throughput approach and here we present an analytical platform that can perform saccharification analysis in a 96-well plate format. This platform has been developed to allow the screening of lignocellulose digestibility of large populations from varied plant species. We have scaled down the reaction volumes for gentle pretreatment, partial enzymatic hydrolysis and sugar determination, to allow large numbers to be assessed rapidly in an automated system. This automated platform works with milligram amounts of biomass, performing ball milling under controlled conditions to reduce the plant materials to a standardised particle size in a reproducible manner. Once the samples are ground, the automated formatting robot dispenses specified and recorded amounts of material into the corresponding wells of 96 deep well plate (Figure 1). Normally, we dispense the same material into 4 wells to have 4 replicates for analysis. Once the plates are filled with the plant material in the desired layout, they are manually moved to a liquid handling station (Figure 2). In this station the samples are subjected to a mild pretreatment with either dilute acid or alkaline and incubated at temperatures of up to 90°C. The pretreatment solution is subsequently removed and the samples are rinsed with buffer to return them to a suitable pH for hydrolysis. The samples are then incubated with an enzyme mixture for a variable length of time at 50°C. An aliquot is taken from the hydrolyzate and the reducing sugars are automatically determined by the MBTH colorimetric method. PMID:21750494

  3. Intermodal transfer of spent fuel

    As a result of the international standardization of containerized cargo handling in ports around the world, maritime shipment handling is particularly uniform. Thus, handier exposure parameters will be relatively constant for ship-truck and ship-rail transfers at ports throughout the world. Inspectors' doses are expected to vary because of jurisdictional considerations. The results of this study should be applicable to truck-to-rail transfers. A study of the movement of spent fuel casks through ports, including the loading and unloading of containers from cargo vessels, afforded an opportunity to estimate the radiation doses to those individuals handling the spent fuels with doses to the public along subsequent transportation routes of the fuel. A number of states require redundant inspections and for escorts over long distances on highways; thus handlers, inspectors, escort personnel, and others who are not normally classified as radiation workers may sustain doses high enough to warrant concern about occupational safety. This paper addresses the question of radiation safety for these workers. Data were obtained during, observation of the offloading of reactor spent fuel (research reactor spent fuel, in this instance) which included estimates of exposure times and distances for handlers, inspectors and other workers during offloading and overnight storage. Exposure times and distance were also for other workers, including crane operators, scale operators, security personnel and truck drivers. RADTRAN calculational models and parameter values then facilitated estimation of the dose to workers during incident-free ship-to-truck transfer of spent fuel

  4. Intermodal transfer of spent fuel

    As a result of the international standardization of containerized cargo handling in ports around the world, maritime shipment handling is particularly uniform. Thus, handler exposure parameters will be relatively constant for ship-truck and ship-rail transfers at ports throughout the world. Inspectors' doses are expected to vary because of jurisdictional considerations. The results of this study should be applicable to truck-to-rail transfers. A study of the movement of spent fuel casks through ports, including the loading and unloading of containers from cargo vessels, afforded an opportunity to estimate the radiation doses to those individuals handling the spent fuels with doses to the public along subsequent transportation routes of the fuel. A number of states require redundant inspections and for escorts over long distances on highways; thus handlers, inspectors, escort personnel, and others who are not normally classified as radiation workers may sustain doses high enough to warrant concern about occupational safety. This paper addresses the question of radiation safety for these workers. Data were obtained during observation of the offloading of reactor spent fuel (research reactor spent fuel, in this instance) which included estimates of exposure times and distances for handlers, inspectors and other workers during offloading and overnight storage. Exposure times and distance were also measured for other workers, including crane operators, scale operators, security personnel and truck drivers. RADTRAN calculational models and parameter values then facilitated estimation of the dose to workers during incident-free ship-to-truck transfer of spent fuel

  5. Antioxidant and functional properties of collagen hydrolysates from Spanish mackerel skin as influenced by average molecular weight.

    Chi, Chang-Feng; Cao, Zi-Hao; Wang, Bin; Hu, Fa-Yuan; Li, Zhong-Rui; Zhang, Bin

    2014-01-01

    In the current study, the relationships between functional properties and average molecular weight (AMW) of collagen hydrolysates from Spanish mackerel (Scomberomorous niphonius) skin were researched. Seven hydrolysate fractions (5.04 ≤ AMW ≤ 47.82 kDa) from collagen of Spanish mackerel skin were obtained through the processes of acid extraction, proteolysis, and fractionation using gel filtration chromatography. The physicochemical properties of the collagen hydrolysate fractions were studied by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), gel filtration chromatography, scanning electron microscope (SEM) and Fourier transform infrared spectroscopy (FTIR). The results indicated that there was an inverse relationship between the antioxidant activities and the logarithm of the AMW of the hydrolysate fractions in the tested AMW range. However, the reduction of AMW significantly enhanced the solubility of the hydrolysate fractions, and a similar AMW decrease of the hydrolysate fractions negatively affected the emulsifying and foaming capacities. This presented as a positive correlation between the logarithm of AMW and emulsion stability index, emulsifying activity index, foam stability, and foam capacity. Therefore, these collagen hydrolysates with excellent antioxidant activities or good functionalities as emulsifiers could be obtained by controlling the effect of the digestion process on the AMW of the resultant hydrolysates. PMID:25090114

  6. Antioxidant and Functional Properties of Collagen Hydrolysates from Spanish Mackerel Skin as Influenced by Average Molecular Weight

    Chang-Feng Chi

    2014-07-01

    Full Text Available In the current study, the relationships between functional properties and average molecular weight (AMW of collagen hydrolysates from Spanish mackerel (Scomberomorous niphonius skin were researched. Seven hydrolysate fractions (5.04 ≤ AMW ≤ 47.82 kDa from collagen of Spanish mackerel skin were obtained through the processes of acid extraction, proteolysis, and fractionation using gel filtration chromatography. The physicochemical properties of the collagen hydrolysate fractions were studied by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE, gel filtration chromatography, scanning electron microscope (SEM and Fourier transform infrared spectroscopy (FTIR. The results indicated that there was an inverse relationship between the antioxidant activities and the logarithm of the AMW of the hydrolysate fractions in the tested AMW range. However, the reduction of AMW significantly enhanced the solubility of the hydrolysate fractions, and a similar AMW decrease of the hydrolysate fractions negatively affected the emulsifying and foaming capacities. This presented as a positive correlation between the logarithm of AMW and emulsion stability index, emulsifying activity index, foam stability, and foam capacity. Therefore, these collagen hydrolysates with excellent antioxidant activities or good functionalities as emulsifiers could be obtained by controlling the effect of the digestion process on the AMW of the resultant hydrolysates.

  7. 40 CFR 180.1246 - Yeast Extract Hydrolysate from Saccharomyces cerevisiae: exemption from the requirement of a...

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Yeast Extract Hydrolysate from... PESTICIDE CHEMICAL RESIDUES IN FOOD Exemptions From Tolerances § 180.1246 Yeast Extract Hydrolysate from... exemption from the requirement of a tolerance for residues of the biochemical pesticide Yeast...

  8. Percutaneous removal of pulmonary artery emboli with hydrolyser catheter in pigs

    To evaluate the efficacy and safety of the Hydrolyser catheter for per,cutaneous treatment of massive pulmonary embolism in pigs. Twelve pigs, each weighing between 55 kg and 89 kg, were used. Radio-opaque 9 cm x 0.8 cm and 4.5 cm x 0.8 cm clots, produced by mixing pig blood with iodinated contrast agent in vacutainers, were injected via the jugular vein until central pulmonary embolism (main and proximal lobar arteries) was obtained with significant systemic and pulmonary hemodynamic modifications. From a femoral approach, the 7-French Hydrolyser thrombectomy catheter was run over a 0.025-inch (0.64-mm) guide wire to remove the pulmonary emboli. Hemodynamic, gasometric and angiographic monitoring was performed before and after treatment. The procedure's safety and completeness of emboli removal was assessed by cardiopulmonary autopsy. Three of the 12 pigs died during embolization. Thrombectomy was therefore performed in 9, and central emboli could be obtained in 7 of the 9. The Hydrolyser could be manipulated only in central pulmonary arteries and could aspirate only central emboli in 5 of the 7 pigs that had them. Despite minimal angiographic improvement seen in these 5, there was no significant hemodynamic and gasometric improvement after treatment. The procedure induced an increase in free hemoglobin blood levels. Autopsies revealed an average of 2 endothelial injuries per pig (mainly adherent endocardial thrombi) in both nontreated (n = 3) and Hydrolyser-treated (n = 9) groups. The Hydrolyser thrombectomy catheter can be promptly positioned and easily steered in central pulmonary arteries. It can be used to partially remove central emboli, but not peripheral pulmonary emboli. Most of the injuries observed may not have been strictly related to Hydrolyser use. The pig might not be a suitable animal model for treatment of massive pulmonary embolism. (author)

  9. Sensory analysis of hydrolysed meat preparations Anlise sensorial de preparaes com hidrolisados de carne

    Maria Elisabeth Machado Pinto E Silva

    2010-06-01

    Full Text Available The use of hydrolysed meat in diets contributes to the improvement of protein, vitamin and mineral supply. This work aims at checking the acceptance pattern in meat hydrolysates. Four preparations have been developed with three types of hydrolysates in domestic-like conditions. Acceptance was verified by means of sensory analysis using the nine-point hedonic scale. Sensory tests have been carried out in three sessions (according to the kind of hydrolysates. In the evaluation file, information on age groups has been included. The statistical analysis has been made by ANOVA and Tukey test. The best accepted preparation have been the turkey and chicken hydrolysed balls. Hydrolysates can be used in many different kinds of preparations, but it is necessary to know both the age group it will be used to and its sensory and chemical-physical features to ensure the taste and the original appearance of the final product.A utilizao de hidrolisados de carne em dietas melhora seu contedo protico, de vitaminas e minerais. O objetivo do presente trabalho foi avaliar a aceitao de hidrolisados de carne. Quatro preparaes foram desenvolvidas com trs tipos de hidrolisados em condies similares s domsticas. . A aceitao foi avaliada com uso de escala hednica de 9 pontos. Os testes foram realizados em trs sesses (de acordo com o tipo de hidrolisado e, incluiu-se na ficha de avaliao informaes de idade. A anlise estatstica foi realizada por ANOVA e teste de Tukey. As preparaes mais aceitas foram os bolinhos com hidrolisados de peru e frango. Os hidrolisados podem ser utilizados em diversas preparaes, sendo necessrio o conhecimento da faixa etria a qual se destinam, suas caractersticas sensoriais e fsico-qumicas, para garantir o sabor e a aparncia do produto final.

  10. Advanced spent fuel storage pools

    Full text: Spent fuel from Power Reactors is currently stored either in at-reactor pools or in independent spent fuel storage installations (ISFSI) using wet or dry storage technology. During the past 15 years, storage capacity of at reactor pools was increased using high density spent fuel storage technology. To achieve maximum capacity, storage racks were replaced in many of the power reactors in operation at least once, some of them went through even various reracking cycles. Independent spent fuel storage installations were established either at the site of power reactors of away from them. They use either storage pools or dry technology, the latter in form of metal casks and concrete silos or vaults. Storage of spent fuel from power reactors must be safe for the public and must protect the environment from its radioactive content. For this purpose, adequate regulation was developed and is available to be applied. However, advances in fuel and core design as well the need for extended storage periods require frequent re-assessment of the available spent fuel storage technology. Improved fuel utilization leads to elevated burn-up resulting in higher heat generation of the spent fuel in the longer term. Also spent MOX fuel generates considerable more heat than spent uranium fuel unloaded from the power reactors 15 years ago. As most of the mechanisms which could endanger fuel integrity are temperature dependent, effective heat removal is one of the challenges spent fuel storage systems have to face. In order to make most efficient use out of high density storage equipment, designer want to take credit from the actual burn-up of the spent fuel. Existing methodology to analyze burn-up credited spent fuel storage racks for criticality safety is being further developed to be applied in the design of dual-purpose casks or multi-purpose-canisters. For poisoned high density storage equipment, long term stability of the material as well as efficient neutron absorption is required. Degrading absorbers which contaminate the coolant of fuel pools and primary circuits and fuel assemblies getting stuck in swollen storage cells are well known problems which already caused considerable headaches to many operators and still continue to do so. Although limited in boron content, borated stainless steel has extensively proved as sufficiently effective and extremely stable neutron poison material. Over and above the basic requirements for maximum safety for operators and the public, logistic in fuel reception is an important aspect to be addressed with the design of independent spent fuel storage facilities. The aspect to keep the operators exposure to radiation as low as reasonably achievable requires expeditious reception of spent fuel and its transfer to the dedicated storage location. Independent wet storage facilities are known for many years to comply best with most of the expectations as described above. However, the assumption to need active cooling systems and to generate secondary waste had caused vendors and users to look favorably at dry storage systems. Despite the remarkable development achieved in dry storage technology, most of the spent fuel generated up to now is stored in fuel pools, either at the reactors or in independent installations. One of the latest achievements in wet storage technology is used in Framatome-ANP's wet storage facility design as currently being performed for the new spent fuel pool building to be constructed at the Goesgen Nuclear Power Station in Switzerland. The advanced design of this independent spent fuel storage facility provides a passive cooling system which reliably removes the heat generated by the spent fuel by natural circulation through air cooled heat exchangers. This progressive design makes extensive use of well balanced safety technology with largely passive safety features developed for Framatome-ANP's Boiling Water Reactor SWR1000. Clearly designed to enable the enforcement of strict foreign material exclusion strategies and state of the art pool water purification equipment reduces operational waste generation to negligible minimum. Due to the passive nature of the operating system, the number of active components which require maintenance is substantially reduced. In addition, due to advanced acquisition methodology of operational data, the frequency of maintenance activities can be determined under consideration of the actual usage. This usually leads to a considerable reduction of human intervention and the time needed to act in radiation areas reducing considerably waste generation and dose burden to personnel. As a facility dedicated to receive and to store fissionable material, regulatory requirements on access controls as defined by the competent regulators are to be met. The advanced wet storage facility design of Framatome-ANP meets safely with all the requirements for safeguards and physical protection including terrorist activities and actions of sabotage. It provides best for safe and reliable storage of spent uranium and MOX fuel for extended periods. Maintenance and repair concepts are available which allow to predict, if correctly applied, such fuel pools to be operable for periods up to 100 years. (author)

  11. Porcine Splenic Hydrolysate has Antioxidant Activity in vivo and in vitro

    HAN, Kyu-Ho; Shimada, Kenichiro; Hayakawa, Toru; Yoon, Taek Joon; FUKUSHIMA, Michihiro

    2014-01-01

    The antioxidant capacity of porcine splenic hydrolysate (PSH) was studied in vitro and in vivo. Peptide hydrolysates were prepared, using the proteolytic enzyme Alcalase®. The molecular weights of PSH were 37,666, 10,673, 6,029, and 2,918 g/mol. Rats were fed a 5% (w/v) PSH diet, instead of a casein diet, for 4 wk. The food intake, body weight gain, and liver weight of rats in the PSH group were similar to those in the control (CONT) group. There were no differences in the serum total cholest...

  12. Salmon protein hydrolysate as a protein source in feed for young pigs

    Nørgaard, Jan Værum; Blaabjerg, Karoline; Poulsen, Hanne Damgaard

    and feed utilization was not significantly different among treatments. No differences were observed in faeces characteristics when scored by visual judgment during two 5-d periods. In conclusion, pigs responded equally to diets containing SPH and FM, and SPH resulted in greater feed intake than SPC.......Salmon protein hydrolysate (SPH) is made from fresh by-products from farmed salmon that are minced and acidified to hydrolyse proteins into peptides and free amino acids. The objective of this study was to evaluate SPH in young pigs compared to soy protein concentrate (SPC), fish meal (FM) and...

  13. Influence of the concentration of locust bean gum on the gelling ability of whey peptic hydrolysates

    Rocha, Cristina M. R.; Hilliou, L.; Teixeira, J. A.; M. P. GONçALVES

    2008-01-01

    The gelling ability of whey proteins can be changed by limited hydrolysis and by the presence of other components such as polysaccharides; depending on the environmental conditions it can either be improved or impaired. In this work the effect of LBG on the heat-set gelation of aqueous whey protein hydrolysates (10 % w/w) from pepsin was assessed at pH 7.0 by small deformation rheology. Whey protein concentrate (WPC) and hydrolysates with a degree of hydrolysis (DH) of 1.5, ...

  14. Systematic Investigation of Antioxidant Activity of Egg White Protein Hydrolysates Obtained by Pepsin

    Shuguo Sun; Meihu Ma; Qinlu Lin; Tao Yang; Huihui Niu

    2013-01-01

    Antioxidative activity of protein hydrolysates from egg white hydrolyzed by Pepsin with different Degrees of Hydrolysis (DHs) was investigated. As the DH increased from 6.47 to 18.22%, the antioxidative activity of Egg White Protein Hydrolysates (EWPHs) first increased and then decreased, except for the reducing power of EWPHs. The EWPHs with DH 16.93% showed higher DPPH radical scavenging activity (96.07±3.84%), hydroxyl radical scavenging activity (36.82±1.46%), superoxide anion scavenging ...

  15. The protein encoded by the rolB plant oncogene hydrolyses indole glucosides.

    Estruch, J J; Schell, J; Spena, A.

    1991-01-01

    The rolB gene of Agrobacterium rhizogenes, whose expression stimulates the formation of roots by transformed plant tissues and other growth alterations in transgenic plants, codes for a beta-glucosidase able to hydrolyse indole-beta-glucosides. Indeed, we show that extracts of bacteria and/or plant tissue expressing the rolB protein hydrolyse indoxyl-beta-glucoside (plant indican). Because of the structural similarity between indoxyl-beta-glucoside and indole-3-acetyl-beta-glucoside (IAA-beta...

  16. Comparison of immunomodulating properties of Beta-lactoglobulin and its hydrolysates.

    Cui-cui Duan; Ai-li Li; Li-jie Yang; Rui Zhao; Wen-guang Fan; Gui-cheng Huo

    2014-01-01

    Cow's milk allergy is one of the most common food allergies in childhood. Beta-lactoglobulin (β- lg) is a dominant allergen in cow's milk. Hydrolysis is known as an effective method to reduce the allergenicity of proteins. Thus, the objective of this study was to compare the allergenicity of β-lg and its hydrolysates using an animal model. Twenty four BALB/c mice were divided into three groups and subcutaneously injected with native bovine β-lg and its hydrolysates on days 0, 7 and 14. During...

  17. Application of enzymatic apple pomace hydrolysate to production of 2,3-butanediol by alkaliphilic Bacillus licheniformis NCIMB 8059.

    Bia?kowska, Aneta M; Gromek, Ewa; Krysiak, Joanna; Sikora, Barbara; Kalinowska, Halina; J?drzejczak-Krzepkowska, Marzena; Kubik, Celina; Lang, Siegmund; Schtt, Fokko; Turkiewicz, Marianna

    2015-12-01

    2,3-Butanediol (2,3-BD) synthesis by a nonpathogenic bacterium Bacillus licheniformis NCIMB 8059 from enzymatic hydrolysate of depectinized apple pomace and its blend with glucose was studied. In shake flasks, the maximum diol concentration in fed-batch fermentations was 113g/L (in 163h, from the hydrolysate, feedings with glucose) while in batch processes it was around 27g/L (in 32h, from the hydrolysate and glucose blend). Fed-batch fermentations in the 0.75 and 30 L fermenters yielded 87.71g/L 2,3-BD in 160h, and 72.39g/L 2,3-BD in 94h, respectively (from the hydrolysate and glucose blend, feedings with glucose). The hydrolysate of apple pomace, which was for the first time used for microbial 2,3-BD production is not only a source of sugars but also essential minerals. PMID:26445877

  18. Pepsin Egg White Hydrolysate Ameliorates Obesity-Related Oxidative Stress, Inflammation and Steatosis in Zucker Fatty Rats

    Garcés-Rimón, M.; González, C.; Uranga, J. A.; López-Miranda, V.; López-Fandiño, R.; Miguel, M.

    2016-01-01

    The aim of this work was to evaluate the effect of the administration of egg white hydrolysates on obesity-related disorders, with a focus on lipid metabolism, inflammation and oxidative stress, in Zucker fatty rats. Obese Zucker rats received water, pepsin egg white hydrolysate (750 mg/kg/day) or Rhizopus aminopeptidase egg white hydrolysate (750 mg/kg/day) for 12 weeks. Lean Zucker rats received water. Body weight, solid and liquid intakes were weekly measured. At the end of the study, urine, faeces, different organs and blood samples were collected. The consumption of egg white hydrolysed with pepsin significantly decreased the epididymal adipose tissue, improved hepatic steatosis, and lowered plasmatic concentration of free fatty acids in the obese animals. It also decreased plasma levels of tumor necrosis factor-alpha and reduced oxidative stress. Pepsin egg white hydrolysate could be used as a tool to improve obesity-related complications. PMID:26985993

  19. Characterization of Animal By-Product Hydrolysates to Be Used as Healthy and Bioactive Ingredients in Food

    Damgaard, Trine Desiree

    tissues showed strong negative correlations with increasing proportions of low molecular peptides in the hydrolysates. Hydrolysates of bovine tissues were tested for their “meat factor” effect. Hydrolysed liver and hanger steak –tissues were capable of enhancing the in vitro iron availability as observed......The world meat production and consumption has increased rapidly over the last couple of decades, due to population and income growth. In contrast to the meat, the consumption of animal by-products has been declining, leaving large amounts of by-products underutilized. As many by-products are highly...... nutritious as well as being good sources of protein, they represent interesting substrates for the generation of bioactive hydrolysates and peptides. Different porcine and bovine by-products were hydrolysed with a mixture consisting of Alcalase®and Protamex, and tested in relation to antioxidant capacity and...

  20. Commercial feasibility of lignocellulose biodegradation: possibilities and challenges.

    Taha, Mohamed; Foda, Mohamed; Shahsavari, Esmaeil; Aburto-Medina, Arturo; Adetutu, Eric; Ball, Andrew

    2016-04-01

    The main source of energy supply worldwide is generated from fossil fuels, which undoubtedly are finite and non-environmental friendly resources. Bioethanol generated from edible resources also has economic and environmental concerns. Despite the immense attention to find an alternative (inedible) source of energy in the last two decades, the total commercial production of 1st generation biofuels is limited and equivalent only to approximately 3% of the total road transport fuel consumption. Lignocellulosic waste represents the most abundant biomass on earth and could be a suitable candidate for producing valuable products including biofuels. However, cellulosic bioethanol has not been produced on a large scale due to the technical barriers involved that make the commercial production of cellulosic bioethanol not economically feasible. This review examines some of the current barriers to commercialization of the process. PMID:27011055

  1. TPS/LDPE blends reinforced with lignocellulose fibers

    Because of their abundance, availability, low abrasiveness and mechanical properties, cellulose fibers have been frequently chosen as reinforcing fillers in composites. Castor bean cake, the residue from biodiesel production, is rich in lignocellulose fibers and proteins. One of these proteins is ricin, a toxin protein. In this work, ricin was denatured by heat treatment in water at 90 deg C for 4 h. Thermoplastic starch (TPS), low density polyethylene (LDPE), maleated polyethylene (used as the compatibilizing agent), and an organophilic clay were processed in the presence of different contents of heat treated castor bean cake. Processing was carried out in a single-screw extruder, at 400 rpm, with heat zones at 130 deg C, 135 deg C, 135 deg C and 130 deg C (from feed zone to die end). The structural and mechanical properties of the resulting polymeric composites were investigated, and revealed the reinforcing effect of the partially purified cellulose fibers. (author)

  2. Experimental modelling of a pilot lignocellulosic pellets stove plant

    Small-scale stoves, producing heat and hot water, are suited for domestic purposes. In order to optimise their efficiency when using lignocellulosic pellets, an important task is to do research on their real performance. The general behaviour depends on many operational factors (air flow and humidity, pressure, etc), dimension and pellet characteristics (moisture, size, raw material, density, friability, etc). In this paper, the first results and general performance of a 24 kW pellet fixed bed stove pilot plant are presented. The plant has been designed to study pellet combustion in the laboratory. The main targets are to reduce emissions of pollutants and to improve energy efficiency. Different situations can be simulated and tested due to its flexible design. Temperatures, pressures, flows and emissions are measured and analysed. An extensive study of different load conditions is presented through the application of both an experiment design technique and the later statistical analysis of the results. Fuel characterisation is also presented. (Author)

  3. Development of a commercial enzymes system for lignocellulosic biomass saccharification

    Kumar, Manoj

    2012-12-20

    DSM Innovation Inc., in its four year effort was able to evaluate and develop its in-house DSM fungal cellulolytic enzymes system to reach enzyme efficiency mandates set by DoE Biomass program MYPP goals. DSM enzyme cocktail is uniquely active at high temperature and acidic pH, offering many benefits and product differentiation in 2G bioethanol production. Under this project, strain and process development, ratio optimization of enzymes, protein and genetic engineering has led to multitudes of improvement in productivity and efficiency making development of a commercial enzyme system for lignocellulosic biomass saccharification viable. DSM is continuing further improvement by additional biodiversity screening, protein engineering and overexpression of enzymes to continue to further lower the cost of enzymes for saccharification of biomass.

  4. Ranking of lignocellulosic biomass pellets through multicriteria modeling

    Sultana, A.; Kumar, A. [Alberta Univ., Edmonton, AB (Canada). Dept. of Mechanical Engineering

    2009-07-01

    A study was conducted in which pellets from different lignocellulosic biomass sources were ranked using a multicriteria assessment model. Five different pellet alternatives were compared based on 10 criteria. The pair-wise comparison was done in order to develop preference indices for various alternatives. The methodology used in this study was the Preference Ranking Organization Method for Enrichment and Evaluation (PROMETHEE). The biomass included wood pellets, straw pellets, switchgrass pellets, alfalfa pellets and poultry pellets. The study considered both quantitative and qualitative criteria such as energy consumption to produce the pellets, production cost, bulk density, NOx emissions, SOx emissions, deposit formation, net calorific value, moisture content, maturity of technology, and quality of material. A sensitivity analysis was performed by changing weights of criteria and threshold values of the criteria. Different scenarios were developed for ranking cost and environmental impacts. According to preliminary results, the wood pellet is the best energy source, followed by switchgrass pellets, straw pellets, alfalfa pellets and poultry pellets.

  5. Bioethanol from Lignocellulosic Biomass: Current Findings Determine Research Priorities

    Kang, Qian; Appels, Lise; Tan, Tianwei

    2014-01-01

    “Second generation” bioethanol, with lignocellulose material as feedstock, is a promising alternative for first generation bioethanol. This paper provides an overview of the current status and reveals the bottlenecks that hamper its implementation. The current literature specifies a conversion of biomass to bioethanol of 30 to ~50% only. Novel processes increase the conversion yield to about 92% of the theoretical yield. New combined processes reduce both the number of operational steps and the production of inhibitors. Recent advances in genetically engineered microorganisms are promising for higher alcohol tolerance and conversion efficiency. By combining advanced systems and by intensive additional research to eliminate current bottlenecks, second generation bioethanol could surpass the traditional first generation processes. PMID:25614881

  6. Bioethanol from lignocellulose - pretreatment, enzyme immobilization and hydrolysis kinetics

    Tsai, Chien Tai

    , concentration of barley straw substrate) and sugar recoveries obtained following enzymatic hydrolysis. Elevated pretreatmenttemperature and longer pretreatment time favoured hydrolysis. However intensive pretreatment at high temperature also causes degradation of cellulose. In addition, [EMIM]Ac pretreated...... that more than 60% of enzymatic activity could be maintained under optimized immobilization condition. In order to evaluate stability, the immobilized enzymes were reused for the hydrolysis of Avicel. No significant loss of activity was observed up to 20th round. Similar glucose yields were obtained...... lignocellulose was found to stabilize and protect the enzymes at elevated temperatures. Therefore lower levels of enzymes were required to obtain similar hydrolytic efficiencies. Optimal pretreatment condition was found with the aid of models based on multiple linear regression. Consider the balanced against...

  7. Functionalized Polymers from Lignocellulosic Biomass: State of the Art

    Wilfred Vermerris

    2013-05-01

    Full Text Available Since the realization that global sustainability depends on renewable sources of materials and energy, there has been an ever-increasing need to develop bio-based polymers that are able to replace petroleum-based polymers. Research in this field has shown strong potential in generating high-performance functionalized polymers from plant biomass. With the anticipated large-scale production of lignocellulosic biomass, lignin, cellulose and hemicellulosic polysaccharides will be abundantly available renewable feedstocks for biopolymers and biocomposites with physico-chemical properties that match or exceed those of petroleum-based compounds. This review examines the state of the art regarding advances and challenges in synthesis and applications of specialty polymers and composites derived from cellulose, hemicellulose and lignin, ending with a brief assessment of genetic modification as a route to tailor crop plants for specific applications.

  8. Compatibility between cellulose and hydrophobic polymer provided by microfibrillated lignocellulose.

    Gindl-Altmutter, Wolfgang; Obersriebnig, Michael; Veigel, Stefan; Liebner, Falk

    2015-01-01

    Microfibrillated lignocellulose (MFLC) was produced from wood subjected to partial lignin extraction using an ethanol/water mixture. After homogenization, the average fibril diameter of MFLC was in the same range as conventional microfibrillated cellulose (MFC). Although MFLC exhibited higher wettability with water compared to MFC, AFM adhesion force measurements revealed high variability in surface polarity of MFLC compared to MFC. Specifically, domains of higher polarity than in MFC but also domains of lower polarity than in MFC were observed in MFLC. This tendency towards amphiphilic behavior of MFLC was used to provide enhanced compatibility with polycaprolactone and polystyrene matrices. With both polymers, a significantly more homogeneous distribution of fibrils was achieved using MFLC compared to MFC. In line with better dispersion of the fibrils, significantly more efficient mechanical reinforcement of polymers was obtained using MFLC compared to MFC. PMID:25348210

  9. Thermogravimetric-mass spectrometric analysis on combustion of lignocellulosic biomass.

    Lpez-Gonzlez, D; Fernandez-Lopez, M; Valverde, J L; Sanchez-Silva, L

    2013-09-01

    Combustion characteristics of biomass main components and three lignocellulosic biomass (fir wood, eucalyptus wood and pine bark) were investigated by thermogravimetric analysis coupled with mass spectrometry. The combustion of biomass was divided into two main steps, devolatilization and char oxidation stage. Heating rate effect was also studied. Generally, the higher the heating rate, the higher the decomposition temperature. Furthermore, the weight loss rate decreased due to particle temperature gradients. Combustion kinetics were studied. Models based on reaction order (Oi), nucleation (Ni) and diffusion (Di) achieved the best fitting to the experimental data. Cellulose oxidation presented the highest activation energies. CO, CO2 and H2O were the main components evolved from combustion. Additionally, light hydrocarbons (CH4 and C2H5) were also present. Finally, nitrogen compounds were in a higher proportion than sulfur compounds being released as primary amines and NOx. PMID:23835261

  10. Ultrasound-assisted fractionation of the lignocellulosic material.

    García, Araceli; Alriols, María González; Llano-Ponte, Rodrigo; Labidi, Jalel

    2011-05-01

    In the present work the effectiveness of different lignocellulosic biomass fractionation processes based on ultrasounds technology was evaluated. Organosolv (acetic acid 60% v/v), alkaline (sodium hydroxide 7.5% w/w) and autohydrolysis treatments were applied at low temperature and the fractionation effectiveness was measured at different sonication conditions of the raw material. The obtained solid fractions were characterized using TAPPI standard methods, and the liquid fractions main components were quantified with the purpose of studying the effect that the treatment conditions had on the obtained by-products quality. Therefore, obtained lignin samples were characterized by ATR-IR spectroscopy and their thermal behaviour by TGA technique. The results showed that ultrasounds application improved the yield and selectivity of the studied processes and that the obtained lignin did not suffer significant modifications in its physicochemical properties. PMID:21377359

  11. Bioethanol production from residual lignocellulosic materials: A review Part 2

    CRISTIAN-TEODOR BURUIANA

    2013-08-01

    Full Text Available Lignocellulosic material (LCM can be employed as feedstock for biorefineries, a concept related to industries designed to process biomass for producing chemicals, fuels and/or electrical power. According to this philosophy, LCM can be fractionated and the resulting fractions employed for specific applications. Bioethanol production from cellulosic fraction of LCM involves: hydrolysis of polysaccharides and fermentation of the monomers into bioethanol. Enzymatic hydrolysis is catalyzed by cellulolytic enzymes and fermentation is carried out by bacteria, yeasts or fungi. The main objective of this article is to review different process integration technologies for bioethanol production from LCM. This paper include: separate hydrolysis and fermentation (SHF, simultaneous saccharification and fermentation (SSF, and simultaneous saccharification and co-fermentation (SSCF methods. Furthermore, the fermentation process and a comparative data of cellulases, hemicellulases and ethanol producing-microorganisms were presented.

  12. Calcium-catalyzed pyrolysis of lignocellulosic biomass components.

    Case, Paige A; Truong, Chi; Wheeler, M Clayton; DeSisto, William J

    2015-09-01

    The present study examines the effect of calcium pretreatment on pyrolysis of individual lignocellulosic compounds. Previous work has demonstrated that the incorporation of calcium compounds with the feedstock prior to pyrolysis has a significant effect on the oxygen content and stability of the resulting oil. The aim of this work was to further explore the chemistry of calcium-catalyzed pyrolysis. Bench-scale pyrolysis of biomass constituents, including lignin, cellulose and xylan is performed and compared to the oils produced from pyrolysis of the same components after calcium pretreatment. The resulting oils were analyzed by quantitative GC-MS and SEC. These analyses, together with data collected from previous work provide evidence which was used to develop proposed reaction pathways for pyrolysis of calcium-pretreatment biomass. PMID:26038329

  13. Lab-scale Technology for Biogas Production from Lignocellulose Wastes

    Lukáš Krátký

    2012-01-01

    Full Text Available Currently-operating biogas plants are based on the treatment of lignocellulose biomass, which is included in materials such as agriculture and forestry wastes, municipal solid wastes, waste paper, wood and herbaceous energy crops. Lab-scale biogas technology was specially developed for evaluating the anaerobic biodegrability and the specific methane yields of solid organic substrates. This technology falls into two main categories – pretreatment equipments, and fermentation equipments. Pretreatment units use physical principles based on mechanical comminution (ball mills, macerator orhydrothermal treatment (liquid hot water pretreatment technology. The biochemical methane potential test is used to evaluate the specific methane yields of treated or non-treated organic substrates. This test can be performed both by lab testing units and by lab fermenter.

  14. Reactors for High Solid Loading Pretreatment of Lignocellulosic Biomass.

    Zhang, Jian; Hou, Weiliang; Bao, Jie

    2016-01-01

    The review summarized the types, the geometry, and the design principle of pretreatment reactors at high solid loading of lignocellulose material. Among the reactors used, the explosion reactors and the helical stirring reactors are to be considered as the practical form for high solids loading pretreatment operation; the comminution reactors and the extruder reactors are difficult to be used as an independent unit, but possible to be used in the combined form with other types of reactors. The principles of the pretreatment reactor design at high solid loading were discussed and several basic principles for the design were proposed. This review provided useful information for choosing the reactor types and designing the geometry of pretreatment operation at the high solids loading. PMID:25757450

  15. Production of nanocrystalline cellulose from lignocellulosic biomass: technology and applications.

    Brinchi, L; Cotana, F; Fortunati, E; Kenny, J M

    2013-04-15

    The use of renewables materials for industrial applications is becoming impellent due to the increasing demand of alternatives to scarce and unrenewable petroleum supplies. In this regard, nanocrystalline cellulose, NCC, derived from cellulose, the most abundant biopolymer, is one of the most promising materials. NCC has unique features, interesting for the development of new materials: the abundance of the source cellulose, its renewability and environmentally benign nature, its mechanical properties and its nano-scaled dimensions open a wide range of possible properties to be discovered. One of the most promising uses of NCC is in polymer matrix nanocomposites, because it can provide a significant reinforcement. This review provides an overview on this emerging nanomaterial, focusing on extraction procedures, especially from lignocellulosic biomass, and on technological developments and applications of NCC-based materials. Challenges and future opportunities of NCC-based materials will be are discussed as well as obstacles remaining for their large use. PMID:23544524

  16. Utilization of Lignocellulosic Waste for the Preparation of Nitrogenous Biofertilizer

    Farhat R. Malik

    2001-01-01

    Full Text Available This work is a part of solid waste management project. Bagasse, a lignocellulosic waste of sugarcane industry was utilized for producing the nitrogenous biofertilizer. Nitrogen fixing free living bacteria were isolated from soil samples using dilution plate method. Selection of bacteria Azotobacter chroococcum was made due to its capability to survive and fix the maximum nitrogen as compared to other bacteria tested in a medium in which bagasse was the only carbon source. A. chroococcum, A. indicus and Azospirilum brasilense were tested for nitrogen fixation from 7 to 28 days. Maximum nitrogen fixed by these bacteria was 67.81, 28.00 and 43.20 mg/L respectively. Experimental results justified that bagasse biomass with A. chroococcum is a good source of nitrogen and organic matter, which can be utilized as a biofertilizer.

  17. Lignocellulosic ethanol: Technology design and its impact on process efficiency.

    Paulova, Leona; Patakova, Petra; Branska, Barbora; Rychtera, Mojmir; Melzoch, Karel

    2015-11-01

    This review provides current information on the production of ethanol from lignocellulosic biomass, with the main focus on relationships between process design and efficiency, expressed as ethanol concentration, yield and productivity. In spite of unquestionable advantages of lignocellulosic biomass as a feedstock for ethanol production (availability, price, non-competitiveness with food, waste material), many technological bottlenecks hinder its wide industrial application and competitiveness with 1st generation ethanol production. Among the main technological challenges are the recalcitrant structure of the material, and thus the need for extensive pretreatment (usually physico-chemical followed by enzymatic hydrolysis) to yield fermentable sugars, and a relatively low concentration of monosaccharides in the medium that hinder the achievement of ethanol concentrations comparable with those obtained using 1st generation feedstocks (e.g. corn or molasses). The presence of both pentose and hexose sugars in the fermentation broth, the price of cellulolytic enzymes, and the presence of toxic compounds that can inhibit cellulolytic enzymes and microbial producers of ethanol are major issues. In this review, different process configurations of the main technological steps (enzymatic hydrolysis, fermentation of hexose/and or pentose sugars) are discussed and their efficiencies are compared. The main features, benefits and drawbacks of simultaneous saccharification and fermentation (SSF), simultaneous saccharification and fermentation with delayed inoculation (dSSF), consolidated bioprocesses (CBP) combining production of cellulolytic enzymes, hydrolysis of biomass and fermentation into one step, together with an approach combining utilization of both pentose and hexose sugars are discussed and compared with separate hydrolysis and fermentation (SHF) processes. The impact of individual technological steps on final process efficiency is emphasized and the potential for use of immobilized biocatalysts is considered. PMID:25485865

  18. Biodiesel from lignocellulosic biomass--prospects and challenges.

    Yousuf, Abu

    2012-11-01

    Biodiesel can be a potential alternative to petroleum diesel, but its high production cost has impeded its commercialization in most parts of the world. One of the main drivers for the generation and use of biodiesel is energy security, because this fuel can be produced from locally available resources, thereby reducing the dependence on imported oil. Many countries are now trying to produce biodiesel from plant or vegetable oils. However, the consumption of large amounts of vegetable oils for biodiesel production could result in a shortage in edible oils and cause food prices to soar. Alternatively, the use of animal fat, used frying oils, and waste oils from restaurants as feedstock could be a good strategy to reduce the cost. However, these limited resources might not meet the increasing demand for clean, renewable fuels. Therefore, recent research has been focused the use of residual materials as renewable feedstock in order to lower the cost of producing biodiesel. Microbial oils or single cell oils (SCOs), produced by oleaginous microorganisms have been studied as promising alternatives to vegetable or seed oils. Various types of agro-industrial residues have been suggested as prospective nutritional sources for microbial cultures. Since the most abundant residue from agricultural crops is lignocellulosic biomass (LCB), this byproduct has been given top-priority consideration as a source of biomass for producing biodiesel. But the biological transformation of lignocellulosic materials is complicated due to their crystalline structure. So, pretreatment is required before they can be converted into fermentable sugar. This article compares and scrutinizes the extent to which various microbes can accumulate high levels of lipids as functions of the starting materials and the fermentation conditions. Also, the obstacles associated with the use of LCB are described, along with a potentially viable approach for overcoming the obstacles that currently preclude the commercial production of biodiesel from agricultural biomass. PMID:22475852

  19. Enzymatic lignocellulose hydrolysis: Improved cellulase productivity by insoluble solids recycling

    Weiss Noah

    2013-01-01

    Full Text Available Abstract Background It is necessary to develop efficient methods to produce renewable fuels from lignocellulosic biomass. One of the main challenges to the industrialization of lignocellulose conversion processes is the large amount of cellulase enzymes used for the hydrolysis of cellulose. One method for decreasing the amount of enzyme used is to recycle the enzymes. In this study, the recycle of enzymes associated with the insoluble solid fraction after the enzymatic hydrolysis of cellulose was investigated for pretreated corn stover under a variety of recycling conditions. Results It was found that a significant amount of cellulase activity could be recovered by recycling the insoluble biomass fraction, and the enzyme dosage could be decreased by 30% to achieve the same glucose yields under the most favorable conditions. Enzyme productivity (g glucose produced/g enzyme applied increased between 30 and 50% by the recycling, depending on the reaction conditions. While increasing the amount of solids recycled increased process performance, the methods applicability was limited by its positive correlation with increasing total solids concentrations, reaction volumes, and lignin content of the insoluble residue. However, increasing amounts of lignin rich residue during the recycle did not negatively impact glucose yields. Conclusions To take advantage of this effect, the amount of solids recycled should be maximized, based on a given processes ability to deal with higher solids concentrations and volumes. Recycling of enzymes by recycling the insoluble solids fraction was thus shown to be an effective method to decrease enzyme usage, and research should be continued for its industrial application.

  20. Preventive effect of feeding high-risk infants a casein hydrolysate formula or an ultrafiltrated whey hydrolysate formula. A prospective, randomized, comparative clinical study

    Halken, S; Høst, A; Hansen, L G; Osterballe, O

    1993-01-01

    In a prospective study of a 1-year birth cohort of 158 high-risk infants the effect of feeding breastmilk, a casein hydrolysate (Nutramigen) or a new ultrafiltrated whey hydrolysate (Profylac) on the development of cow milk protein allergy/intolerance (CMPA/CMPI) was assessed and compared. All the...... period this regimen was combined with avoidance of solid foods and cow milk protein. All mothers had unrestricted diets and were encouraged to do breastfeeding only. Moreover, avoidance of daily exposure to tobacco smoking, furred pets and dust-collecting materials in the bedroom was advised. The infants....... None of the infants showed reactions against Nutramigen or Profylac. In 4 infants symptoms were provoked by breastmilk when the mother ingested cow milk and in 1 only by cow milk.(ABSTRACT TRUNCATED AT 250 WORDS)...

  1. Spent-fuel-storage alternatives

    1980-01-01

    The Spent Fuel Storage Alternatives meeting was a technical forum in which 37 experts from 12 states discussed storage alternatives that are available or are under development. The subject matter was divided into the following five areas: techniques for increasing fuel storage density; dry storage of spent fuel; fuel characterization and conditioning; fuel storage operating experience; and storage and transport economics. Nineteen of the 21 papers which were presented at this meeting are included in this Proceedings. These have been abstracted and indexed. (ATT)

  2. Evolutionarily Engineered Ethanologenic Yeast Detoxifies Lignocellulosic Biomass Conversion Inhibitors by Reprogrammed Pathways

    Lignocellulosic biomass conversion inhibitors furfural and HMF inhibit microbial growth and interfere with subsequent fermentation of ethanol, posing significant challenges for a sustainable cellulosic ethanol conversion industry. Numerous yeast genes were found to be associated with the inhibitor ...

  3. Genomic mechanisms of inhibitor-detoxification for low-cost lignocellulosic bioethanol conversion

    One major challenges of sustainable lignocellulosic biomass conversion to ethanol is to overcome inhibitors generated from biomass pretreatment. Aldehyde inhibitors such as furfural, 5-hydroxymethylfurfural, cinnamaldehyde, phenylacetylaldehyde, and 4-hydroxybenzaldehyde, are common and potent inhi...

  4. SELF-ASSEMBLED LIGNOCELLULOSE MICELLES: A NEW GENERATION OF VALUE-ADDED FUNCTIONAL NANOSTRUCTURES

    Xiaohui Wang Mail

    2011-01-01

    Full Text Available Lignocellulose-based self-assembled micelles have emerged as a new generation of value-added functional nanostructures that show promise to address issues concerning the depletion of non-renewable resources; also these materials may contribute to the growing enthusiasm of utilizing biomass resources. Lignocellulose micelles can be conveniently prepared by self-assembly of amphiphilic lignocellulose derivatives in aqueous solution. They show great potential for applications in disparate fields, e.g. drug delivery, bioimaging diagnosis, sensing, nanoreacting, and so on. However, as a new research topic, a lot of research work would be needed to find out the critical structural factors that correlate with the formation, stability, morphology, and flexibility of lignocellulose micelles.

  5. High-throughput screening for ionic liquids dissolving (ligno-)cellulose.

    Zavrel, Michael; Bross, Daniela; Funke, Matthias; Büchs, Jochen; Spiess, Antje C

    2009-05-01

    The recalcitrance of lignocellulosic biomass poses a major challenge for its sustainable and cost-effective utilization. Therefore, an efficient pretreatment is decisive for processes based on lignocellulose. A green and energy-efficient pretreatment could be the dissolution of lignocellulose in ionic liquids. Several ionic liquids were identified earlier which are capable to dissolve (ligno-)cellulose. However, due to their multitude and high costs, a high-throughput screening on small scale is essential for the determination of the most efficient ionic liquid. In this contribution two high-throughput systems are presented based on extinction or scattered light measurements. Quasi-continuous dissolution profiles allow a direct comparison of up to 96 ionic liquids per experiment in terms of their dissolution kinetics. The screening results indicate that among the ionic liquids tested EMIM Ac is the most efficient for dissolving cellulose. Moreover, it was observed that AMIM Cl is the most effective ionic liquid for dissolving wood chips. PMID:19157872

  6. Dynamic Simulation, Sensitivity and Uncertainty Analysis of a Demonstration Scale Lignocellulosic Enzymatic Hydrolysis Process

    Prunescu, Remus Mihail; Sin, Gürkan

    2014-01-01

    This study presents the uncertainty and sensitivity analysis of a lignocellulosic enzymatic hydrolysis model considering both model and feed parameters as sources of uncertainty. The dynamic model is parametrized for accommodating various types of biomass, and different enzymatic complexes...

  7. Solar assisted alkali pretreatment of garden biomass: Effects on lignocellulose degradation, enzymatic hydrolysis, crystallinity and ultra-structural changes in lignocellulose.

    Gabhane, Jagdish; William, S P M Prince; Vaidya, Atul N; Das, Sera; Wate, Satish R

    2015-06-01

    A comprehensive study was carried out to assess the effectiveness of solar assisted alkali pretreatment (SAAP) on garden biomass (GB). The pretreatment efficiency was assessed based on lignocellulose degradation, conversion of cellulose into reducing sugars, changes in the ultra-structure and functional groups of lignocellulose and impact on the crystallinity of cellulose, etc. SAAP was found to be efficient for the removal of lignin and hemicellulose that facilitated enzymatic hydrolysis of cellulose. FTIR and XRD studies provided details on the effectiveness of SAAP on lignocellulosic moiety and crystallinity of cellulose. Scanning electron microscopic analysis showed ultra-structural disturbances in the microfibrils of GB as a result of pretreatment. The mass balance closer of 97.87% after pretreatment confirmed the reliability of SAAP pretreatment. Based on the results, it is concluded that SAAP is not only an efficient means of pretreatment but also economical as it involved no energy expenditure for heat generation during pretreatment. PMID:25816769

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

    Keikhosro Karimi; Mohammad J. Taherzadeh

    2008-01-01

    Lignocelluloses are often a major or sometimes the sole components of different waste streams from various industries, forestry, agriculture and municipalities. Hydrolysis of these materials is the first step for either digestion to biogas (methane) or fermentation to ethanol. However, enzymatic hydrolysis of lignocelluloses with no pretreatment is usually not so effective because of high stability of the materials to enzymatic or bacterial attacks. The present work is dedicated to reviewing ...

  9. An Efficient Process for Pretreatment of Lignocelluloses in Functional Ionic Liquids

    Dong, Shi-Jia; Zhang, Bi-Xian; Gao, Yun-Fei; Hu, Xiao-Mei

    2015-01-01

    Background and Aims. The complex structure of the lignocelluloses is the main obstacle in the conversion of lignocellulosic biomass into valuable products. Ionic liquids provide the opportunities for their efficient pretreatment for biomass. Therefore, in this work, pretreatment of corn stalk was carried out in ultrasonic-assisted ionic liquid including 1-butyl-3-methylimidazolium chloride [BMIM]Cl, 1-H-3-methylimidazolium chloride [HMIM]Cl, and 1-(1-propylsulfonic)-3-imidazolium chloride [HS...

  10. Integrating social and value dimensions into sustainability assessment of lignocellulosic biofuels

    Raman, Sujatha; Mohr, Alison; Helliwell, Richard; Ribeiro, Barbara; Shortall, Orla; Smith, Robert David Jonathan; Millar, Kate

    2015-01-01

    The paper clarifies the social and value dimensions for integrated sustainability assessments of lignocellulosic biofuels. We develop a responsible innovation approach, looking at technology impacts and implementation challenges, assumptions and value conflicts influencing how impacts are identified and assessed, and different visions for future development. We identify three distinct value-based visions. From a techno-economic perspective, lignocellulosic biofuels can contribute to energy se...

  11. Bacterial community composition shifts in the gut of Periplaneta americana fed on different lignocellulosic materials

    Bertino-Grimaldi, Danielle; Medeiros, Marcelo N; Vieira, Ricardo P.; Cardoso, Alexander M.; Turque, Aline S; Silveira, Cynthia B.; Rodolpho M. Albano; Bressan-Nascimento, Suzete; Garcia, Elói S; Souza, Wanderley de; Martins, Orlando B.; Machado, Ednildo A.

    2013-01-01

    Abstract Cockroaches are insects that can accommodate diets of different composition, including lignocellulosic materials. Digestion of these compounds is achieved by the insect’s own enzymes and also by enzymes produced by gut symbionts. The presence of different and modular bacterial phyla on the cockroach gut tract suggests that this insect could be an interesting model to study the organization of gut bacterial communities associated with the digestion of different lignocellulosic diets. ...

  12. Molecular Adaptation Mechanisms Employed by Ethanologenic Bacteria in Response to Lignocellulose-derived Inhibitory Compounds

    Ibraheem, Omodele; Ndimba, Bongani K.

    2013-01-01

    Current international interest in finding alternative sources of energy to the diminishing supplies of fossil fuels has encouraged research efforts in improving biofuel production technologies. In countries which lack sufficient food, the use of sustainable lignocellulosic feedstocks, for the production of bioethanol, is an attractive option. In the pre-treatment of lignocellulosic feedstocks for ethanol production, various chemicals and/or enzymatic processes are employed. These methods gene...

  13. Application of steam explosion for the pretreatment of the lignocellulosic raw materials

    Jacquet, Nicolas; Vanderghem, Caroline; Blecker, Christophe; Paquot, Michel

    2010-01-01

    Application of steam explosion for the pretreatment of the lignocellulosic raw materials. Steam explosion is a thermomechanochemical process which allows the breakdown of lignocellulosic structural components by steam heating, hydrolysis of glycosidic bonds by organic acid formed during the process and shearing forces due to the expansion of the moisture. The process is composed of two distinct stages: vapocracking and explosive decompression. Cumul effects of both phases include modification...

  14. Tolerance and adaptive evolution of triacylglycerol-producing Rhodococcus opacus to lignocellulose-derived inhibitors

    2015-01-01

    Background Lignocellulosic biomass has been investigated as a renewable non-food source for production of biofuels. A significant technical challenge to using lignocellulose is the presence of microbial growth inhibitors generated during pretreatment processes. Triacylglycerols (TAGs) are potential precursors for lipid-based biofuel production. Rhodococcus opacus MITXM-61 is an oleaginous bacterium capable of producing large amounts of TAGs on high concentrations of glucose and xylose present...

  15. Lignocellulosic ethanol production by starch-base industrial yeast under PEG detoxification

    Xiumei Liu; Wenjuan Xu; Liaoyuan Mao; Chao Zhang; Peifang Yan; Zhanwei Xu; Z. Conrad Zhang

    2016-01-01

    Cellulosic ethanol production from lignocellulosic biomass offers a sustainable solution for transition from fossil based fuels to renewable alternatives. However, a few long-standing technical challenges remain to be addressed in the development of an economically viable fermentation process from lignocellulose. Such challenges include the needs to improve yeast tolerance to toxic inhibitory compounds and to achieve high fermentation efficiency with minimum detoxification steps after a simpl...

  16. Relationship between Calorific Value and Elementary Composition of Torrefied Lignocellulosic Biomass

    S. Yusup; D. Subbarao; Tsutsui, T; W. Omar; Uemura, Y.

    2010-01-01

    In this study, the relationship between calorific value and elementary composition of torrefied oil palm wastes (empty fruit bunches, mesocarp fiber and kernel shell) and other lignocellulosic biomass is discussed. Several correlations for calorific value vs. elementary composition for biomass were examined for their applicability to torrefied lignocellulosic biomass. One of the correlations was selected as the most appropriate for the purpose, based on average absolute error between observed...

  17. Saccharification protocol for small-scale lignocellulosic biomass samples to test processing of cellulose into glucose

    Van Acker, Rebecca; Vanholme, Ruben; Piens, Kathleen; Boerjan, Wout

    2016-01-01

    Second generation biofuels are derived from inedible lignocellulosic biomass of food and non-food crops. Lignocellulosic biomass is mainly composed of cell walls that contain a large proportion of cellulosic and hemicellulosic polysaccharides. An interesting route to generate biofuels and bio-based materials is via enzymatic hydrolysis of cell wall polysaccharides into fermentable sugars, a process called saccharification. The released sugars can then be fermented to fuels, e.g. by use of yea...

  18. LIGNOCELLULOSIC FILLER/ RECYCLED HDPE COMPOSITES: EFFECT OF FILLER TYPE ON PHYSICAL AND FLEXURAL PROPERTIES

    Abdollah Najafi; Habibollah Khademi-Eslam Mail

    2011-01-01

    The aim of the research was to study the potential of lignocellulosic fillers such as flour of rice hull, wood saw dust, sanding flour from Medium Density Fiberboard (MDF), and sawdust from particleboard as reinforcement for recycled high density polyethylene. Natural filler HDPE composites were made from recycled HDPE and lignocellulosic fillers at 60% by weight filler loadings using a dry blend/hot press method. In all compounds 3 per hundred compound (phc) Maleic Anhydride Polyethylene (MA...

  19. Fungal-mediated consolidated bioprocessing: the potential of Fusarium oxysporum for the lignocellulosic ethanol industry.

    Ali, Shahin S; Nugent, Brian; Mullins, Ewen; Doohan, Fiona M

    2016-03-01

    Microbial bioprocessing of lignocellulose to bioethanol still poses challenges in terms of substrate catabolism. The most important challenge is to overcome substrate recalcitrance and to thus reduce the number of steps needed to biorefine lignocellulose. Conventionally, conversion involves chemical pretreatment of lignocellulose, followed by hydrolysis of biomass to monomer sugars that are subsequently fermented into bioethanol. Consolidated bioprocessing (CBP) has been suggested as an efficient and economical method of manufacturing bioethanol from lignocellulose. CBP integrates the hydrolysis and fermentation steps into a single process, thereby significantly reducing the amount of steps in the biorefining process. Filamentous fungi are remarkable organisms that are naturally specialised in deconstructing plant biomass and thus they have tremendous potential as components of CBP. The fungus Fusarium oxysporum has potential for CBP of lignocellulose to bioethanol. Here we discuss the complexity and potential of CBP, the bottlenecks in the process, and the potential influence of fungal genetic diversity, substrate complexity and new technologies on the efficacy of CPB of lignocellulose, with a focus on F. oxysporum. PMID:26888202

  20. Spent fuel reprocessing. Main operations

    The behaviour of spent fuels from nuclear reactors is one of the major concern of the nuclear industry. Two alternatives exist: direct disposal or reprocessing, the choice between both strategies depends on political, economical and environmental stakes. This document is devoted to the description of the Purex process (plutonium uranium refining by extraction) used for the reprocessing of spent fuels from water cooled reactors: 1 - Stakes and strategies; 2 - characteristics of fuels: new fuels, conditions of irradiation, characteristics of irradiated fuels (PWR-type fuels, FBR-type fuels, GCR-type fuels, research and propulsion reactor fuels, amount of unloaded spent fuels); 3 - goals and specific constraints: technical goals (efficiency of uranium and plutonium recovery, specification of finite products, limitation of radioactive effluents, wastes conditioning), specific reprocessing constraints; 4 - general considerations about processes: evolution, principal steps; 5 - head-end operations: on reactor site, transport of spent fuel, unloading at the reprocessing plant, storage, mechanical treatments, dissolution (uranium oxide, mixed uranium-plutonium oxides, metal fuels), treatment of gaseous wastes (nitrogen oxides, iodine, filtering), clarifying of solutions (unsoluble particulates, apparatuses), evaluation of the nuclear materials content, adjustment of solutions; 6 - Separation and purification: chemistry (aqueous nitrous solutions, nitrogen compounds, actinides, fission products), extraction mechanisms (solvent properties, nitrogen compounds, actinides, fission products, solvent evolution), extraction cycles (first cycle, plutonium purification cycles, uranium purification cycles), solvent processing, apparatuses (mixers-settlers, pulsed columns, centrifugal extractors, modeling); 7 - Elaboration of finite products: uranium, plutonium (oxalate process, denitration), recycling of out-off specification plutonium oxides. (J.S.)