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1

Ethanolic fermentation of pentoses in lignocellulose hydrolysates  

Energy Technology Data Exchange (ETDEWEB)

In the fermentation of lignocellulose hydrolysates to ethanol, two major problems are encountered: the fermentation of the pentose sugar xylose, and the presence of microbial inhibitors. Xylose can be directly fermented with yeasts; such as Pachysolen tannophilus, Candida shehatae, and Pichia stipis, or by isomerization of xylose to xylulose with the enzyme glucose (xylose) isomerase, and subsequent fermentation with bakers yeast, Saccharomyces cerevisiae. The direct fermentation requires low, carefully controlled oxygenation, as well as the removal of inhibitors. Also, the xylose-fermenting yeasts have a limited ethanol tolerance. The combined isomerization and fermentation with XI and S. cerevisiae gives yields and productivities comparable to those obtained in hexose fermentations without oxygenation and removal of inhibitors. However, the enzyme is not very stable in a lignocellulose hydrolysate, and S. cerevisiae has a poorly developed pentose phosphate shunt. Different strategies involving strain adaptation, and protein and genetic engineering adopted to overcome these different obstacles, are discussed.

Hahn-Haegerdal, B.; Linden, T.; Senac, T.; Skoog, K. [Lund Univ. Chemical Center (Sweden)

1991-12-31

2

The fermentation of lignocellulose hydrolysates with xylose isomerases and yeasts  

Energy Technology Data Exchange (ETDEWEB)

Untreated spent sulphite liquor (SSL) was fermented with Canida tropicalis, Pichia stipitis, Pachysolen tannophilus, Schizosaccharomyces pombe, Saccharomyces cerevisiae and a co-culture of P. Tannophilus and A. cerevisiae, in the presence of xylose isomerases and 4.6 mM azide. The highest yield of ethanol, 0.41 g/g total sugar was obtained with S. cerevisiae, C. tropicalis, and P. tannophilus produced considerble amounts of polyoles, mainly xylitol. With P. stipitis sugar uptake was rapidly inhibited in untreated SSL. The presence of azide contributed to the yield by about 0.04. The fermentation of hydrogen fluoride-pretreated and acid-hydrolysed wheat straw with S. cerevisiae, xylose isomerase, and azide gave a yield of 0.40 g ethanol/g total sugar. In this substrate the xylose utilisation was 84% compared with 51% in SSL. In the concentration range appropriate for enzymatic xylose isomerization, xylulose was measured in a lignocellulose hydrolysate using HPLC with two hydrogen loaded ion exchange columns in series. SSL was used as a model for lignocellulose hydrolysates. The enzymatic isomerization of xylose to xylulose was followed directly in SSL, providing a method for the direct determination of xylose isomerase activity in lignocellulose hydrolysates. Three different xylose isomerase preparations of L. brevis whole cells were compared with a commercial enzyme preparation Maxazyme GI-immob., with respect to activity and stability. From a continuous SSL fermentation plant, two species of yeasts were isolated, S. cerevisiae and Pichia membranaefaciens. One of the isolates of S. cerevisiae, no. 3 was heavily flocculating. Without acetic acid present, both bakers` yeast and isolate no. 3 showed catabolite repression and fermented glucose and galactose sequentially. Galactose fermentation with bakers` yeast was strongly inhibited by acetic acid at pH values below 6. Isolate no. 3 fermented galactose, glucose and mannose, in the presence of acetic acid even at pH.

Linden, T.

1992-09-01

3

The fermentation of lignocellulose hydrolysates with xylose isomerases and yeasts  

Energy Technology Data Exchange (ETDEWEB)

Untreated spent sulphite liquor (SSL) was fermented with Canida tropicalis, Pichia stipitis, Pachysolen tannophilus, Schizosaccharomyces pombe, Saccharomyces cerevisiae and a co-culture of P. Tannophilus and A. cerevisiae, in the presence of xylose isomerases and 4.6 mM azide. The highest yield of ethanol, 0.41 g/g total sugar was obtained with S. cerevisiae, C. tropicalis, and P. tannophilus produced considerble amounts of polyoles, mainly xylitol. With P. stipitis sugar uptake was rapidly inhibited in untreated SSL. The presence of azide contributed to the yield by about 0.04. The fermentation of hydrogen fluoride-pretreated and acid-hydrolysed wheat straw with S. cerevisiae, xylose isomerase, and azide gave a yield of 0.40 g ethanol/g total sugar. In this substrate the xylose utilisation was 84% compared with 51% in SSL. In the concentration range appropriate for enzymatic xylose isomerization, xylulose was measured in a lignocellulose hydrolysate using HPLC with two hydrogen loaded ion exchange columns in series. SSL was used as a model for lignocellulose hydrolysates. The enzymatic isomerization of xylose to xylulose was followed directly in SSL, providing a method for the direct determination of xylose isomerase activity in lignocellulose hydrolysates. Three different xylose isomerase preparations of L. brevis whole cells were compared with a commercial enzyme preparation Maxazyme GI-immob., with respect to activity and stability. From a continuous SSL fermentation plant, two species of yeasts were isolated, S. cerevisiae and Pichia membranaefaciens. One of the isolates of S. cerevisiae, no. 3 was heavily flocculating. Without acetic acid present, both bakers' yeast and isolate no. 3 showed catabolite repression and fermented glucose and galactose sequentially. Galactose fermentation with bakers' yeast was strongly inhibited by acetic acid at pH values below 6. Isolate no. 3 fermented galactose, glucose and mannose, in the presence of acetic acid even at pH.

Linden, T.

1992-01-01

4

Fermentation of lignocellulosic hydrolysates: Inhibition and detoxification  

Energy Technology Data Exchange (ETDEWEB)

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

Palmqvist, E.

1998-02-01

5

Production of Succinic Acid for Lignocellulosic Hydrolysates  

Energy Technology Data Exchange (ETDEWEB)

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.

Davison, B.H.; Nghiem, J.

2002-06-01

6

Cultivation of lipid-producing bacteria with lignocellulosic biomass: effects of inhibitory compounds of lignocellulosic hydrolysates.  

Science.gov (United States)

Lignocellulosic biomass has been recognized as a promising feedstock for the fermentative production of biofuel. However, the pretreatment of lignocellulose generates a number of by-products, such as furfural, 5-hydroxylmethyl furfural (5-HMF), vanillin, vanillic acids and trans-p-coumaric acid (TPCA), which are known to inhibit microbial growth. This research explores the ability of Rhodococcus opacus PD630 to use lignocellulosic biomass for production of triacylglycerols (TAGs), a common lipid raw material for biodiesel production. This study reports that R. opacus PD630 can grow well in R2A broth in the presence of these model inhibitory compounds while accumulating TAGs. Furthermore, strain PD630 can use TPCA, vanillic acid, and vanillin as carbon sources, but can only use TPCA and vanillic acid for TAG accumulation. Strain PD630 can also grow rapidly on the hydrolysates of corn stover, sorghum, and grass to accumulate TAGs, suggesting that strain PD630 is well-suited for bacterial lipid production from lignocellulosic biomass. PMID:24698742

Wang, Baixin; Rezenom, Yohannes H; Cho, Kun-Ching; Tran, Janessa L; Lee, Do Gyun; Russell, David H; Gill, Jason J; Young, Ryland; Chu, Kung-Hui

2014-06-01

7

Fermentative performance of bacteria and yeasts in lignocellulose hydrolysates  

Energy Technology Data Exchange (ETDEWEB)

The sugar consumption rates and the product formation of yeasts (Saccharomyces cidri NCYC 775, S. cerevisiae NCYC 1047, S.cerevisiae ATCC 4132) and bacteria (Lactobacillus brevis DSM 20054, Lactococcus lactis ssp. lactis ATCC 19435, Escherichia coli ATCC 11303, Zymomonas mobilis ATCC 31821) were investigated in spent sulphite liquor and an enzymatic hydrolysate of steam-pretreated Salix caprea at different pH values in order to elucidate the suitability of the organisms with respect to future genetic engineering approaches. The possible inhibitory action of the two substrates on the investigated microorganisms was also considered. S.cerevisiae emerged as one of the better candidates, owing to its fast sugar consumption rate and efficient ethanol production. (author)

Olsson, Lisbeth; Hahn-Haegerdal, B. (Lund Univ. (Sweden). Dept. of Applied Microbiology)

1993-01-01

8

Conditioning of SO2-ethanol-water (SEW) spent liquor from lignocellulosics for ABE fermentation to biofuels and chemicals  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This thesis introduces a biorefinery process to fractionate lignocellulosics followed by treatment of the produced hydrolysate for microbial fermentation to acetone, butanol and ethanol (ABE). The process utilizes SO2-Ethanol-Water (SEW) fractionation technology and a ‘conditioning’ protocol to treat SEW spent liquor for ABE fermentation by Clostridia bacteria. It is found that SEW fractionation of spruce chips, mixed softwood biomass and Oil Palm Empty Fruit Bunch (OPEFB) at condition...

Sklavounos, Evangelos

2014-01-01

9

Ethanol from lignocellulose : Alkali detoxification of dilute-acid spruce hydrolysates  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Detoxification of dilute-acid lignocellulose hydrolysates by treatment with Ca(OH)2 (overliming) efficiently improves the production of fuel ethanol, but is associated with drawbacks like sugar degradation and CaSO4 precipitation. In factorial designed experiments, in which pH and temperature were varied, dilute-acid spruce hydrolysates were treated with Ca(OH)2, NH4OH or NaOH. The concentrations of sugars and inhibitory compounds were measured before and after the treatments. The fermentabil...

Alriksson, Bjo?rn

2006-01-01

10

[Effect of byproducts in lignocellulose hydrolysates on ethanol fermentation by Issatchenkia orientalis].  

Science.gov (United States)

Byproducts in lignocellulose hydrolysates, namely sodium formate (1 to 5 g/L), sodium acetic (2.5 to 8.0 g/L), furfural (0.2-2 g/L), 5-hydroxymethylfurfural (5-HMF, 1 to 1.0 g/L) or vanillin (0.5 to 2 g/L) were used to evaluate their effects on ethanol fermentation by Issatchenkia orientalis HN-1 using single factor test and the response surface central composite experiment. Results showed that most of the byproducts had no obvious inhibition on the production of ethanol, except for the addition of 2 g/L vanillin or 1 g/L of 5-HMF, which reduced the ethanol production by 20.38% and 11.2%, respectively. However, high concentration of some byproducts in lignocellulose hydrolysates, such as sodium formate (1 to 5 g/L), sodium acetic (2.5 to 8.0 g/L), furfural (0.2 to 2 g/L) and vanillin (0.5 to 2 g/L) inhibited the growth of I. orientalis HN-1 significantly. Compared with the control, the dry cell weight of I. orientalis HN-1 decreased by 25.04% to 37.02%, 28.83% to 43.82%, 20.06% to 37.60% and 26.39% to 52.64%, respectively, when the above components were added into the fermentation broth and the fermentation lasted for 36 h. No significant interaction effect of the various inhibitors (sodium formate, sodium acetic, furfural and vanillin) except for vanillin single factor on the ethanol production was observed based on the central composite experiments. The concentrations of byproducts in most lignocellulose hydrolysates were below the initial inhibition concentration on ethanol production by Issatchenkia orientalis HN-1, which indicated that Issatchenkia orientalis HN-1 can be used for ethanol production from lignocellulose hydrolysates. PMID:25118399

Wang, Fengqin; Liu, Yaqiong; Zhang, Rui; Wang, Yuanyuan; Xie, Hui; Song, Andong

2014-05-01

11

Ethanol fermentation from lignocellulosic hydrolysate by a recombinant xylose- and cellooligosaccharide-assimilating yeast strain  

Energy Technology Data Exchange (ETDEWEB)

The sulfuric acid hydrolysate of lignocellulosic biomass, such as wood chips, from the forest industry is an important material for fuel bioethanol production. In this study, we constructed a recombinant yeast strain that can ferment xylose and cellooligosaccharides by integrating genes for the intercellular expressions of xylose reductase and xylitol dehydrogenase from Pichia stipitis, and xylulokinase from Saccharomyces cerevisiae and a gene for displaying ss-glucosidase from Aspergillus acleatus on the cell surface. In the fermentation of the sulfuric acid hydrolysate of wood chips, xylose and cellooligosaccharides were completely fermented after 36 h by the recombinant strain, and then about 30 g/l ethanol was produced from 73 g/l total sugar added at the beginning. In this case, the ethanol yield of this recombinant yeast was much higher than that of the control yeast. These results demonstrate that the fermentation of the lignocellulose hydrolysate is performed efficiently by the recombinant Saccharomyces strain with abilities for xylose assimilation and cellooligosaccharide degradation. (orig.)

Katahira, Satoshi; Fukuda, Hideki [Kobe Univ. (Japan). Div. of Molecular Science; Mizuike, Atsuko; Kondo, Akihiko [Kobe Univ. (Japan). Dept. of Chemical Science and Engineering

2006-10-15

12

Isolation of Filamentous Fungi Exhibiting High Endoxylanase Activity in Lignocellulose Hydrolysate.  

Science.gov (United States)

For complete degradation of hemicellulose into its monomers from lignocellulose biomass, the synergistic action of a broad range of hydrolytic enzymes is needed. Therefore, production of enzymes from their natural producer is desirable. To obtain a powerful ?-1,4-endoxylanase producing fungus, 304 environmental samples were collected from various locations in Singapore, leading to 603 isolates. Among them, 71 exhibiting ?-1,4-endoxylanase activity were identified belonging mainly to the genera of Aspergillus, Penicillium, and Trichoderma. Further analysis revealed Aspergillus niger DSM 26641 as a potential and stable ?-1,4-endoxylanase producer, being able to grow in hydrothermal lignocellulose hydrolysate exhibiting its maximal ?-1,4-endoxylanase activity at pH 4 and 60 °C. This strain is thought to be very suitable for lactic acid production in a simultaneous saccharification and fermentation at pH values below 5. PMID:25432348

Ottenheim, Christoph; Meier, Kirstin; Zimmermann, Wolfgang; Wu, Jin Chuan

2014-11-30

13

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

Science.gov (United States)

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

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

2012-01-01

14

Repetitive succinic acid production from lignocellulose hydrolysates by enhancement of ATP supply in metabolically engineered Escherichia coli.  

Science.gov (United States)

In this study, repetitive production of succinic acid from lignocellulose hydrolysates by enhancement of ATP supply in metabolically engineered E. coli is reported. Escherichia coli BA305, a pflB, ldhA, ppc, and ptsG deletion strain overexpressing ATP-forming phosphoenolpyruvate (PEP) carboxykinase (PEPCK), produced a final succinic acid concentration of 83 g L(-1) with a high yield of 0.87 g g(-1) total sugar in 36 h of three repetitive fermentations of sugarcane bagasse hydrolysate. Furthermore, simultaneous consumption of glucose and xylose was achieved, and the specific productivity and yield of succinic acid were almost maintained constant during the repetitive fermentations. PMID:23819977

Liang, Liya; Liu, Rongming; Li, Feng; Wu, Mingke; Chen, Kequan; Ma, Jiangfeng; Jiang, Min; Wei, Ping; Ouyang, Pingkai

2013-09-01

15

Laccase production by Aspergillus heteromorphus using distillery spent wash and lignocellulosic biomass.  

Science.gov (United States)

Laccase is among the major enzymes which plays an important role in ligninolytic system of fungi. Laccase production by Aspergillus heteromorphus was studied using anaerobically treated distillery spent wash (ADSW) and lignocellulosic biomass. Lignocellulosic biomass (rice straw, wheat straw and sugarcane bagasse) generated during biomass processing leads to solid waste and distillery spent wash is unwanted liquid waste produced by distilleries, both causes environmental pollution. Two mineral media and anaerobically treated distillery spent wash medium was tested for laccase production. Enzyme production in various media and in presence and absence of lignocellulosic biomass supplements showed that anaerobically treated distillery spent wash medium was a better laccase inducer medium than the mineral media. Addition of lignocellulosic biomass enhances laccase production and highest laccase activity was obtained in 5% anaerobically treated distillery spent wash medium with rice straw. PMID:20036461

Singh, Anita; Bajar, Somvir; Bishnoi, Narsi R; Singh, Namita

2010-04-15

16

Physiological response of Saccharomyces cerevisiae to weak acids present in lignocellulosic hydrolysate.  

Science.gov (United States)

Weak acids are present in lignocellulosic hydrolysate as potential inhibitors that can hamper the use of this renewable resource for fuel and chemical production. To study the effects of weak acids on yeast growth, physiological investigations were carried out in batch cultures using glucose as carbon source in the presence of acetic, formic, levulinic, and vanillic acid at three different concentrations at pH 5.0. The results showed that acids at moderate concentrations can stimulate the glycolytic flux, while higher levels of acid slow down the glycolytic flux for both aerobically and anaerobically grown yeast cells. In particular, the flux distribution between respiratory and fermentative growth was adjusted to achieve an optimal ATP generation to allow a maintained energy level as high as it is in nonstressed cells grown exponentially on glucose under aerobic conditions. In addition, yeast cells exposed to acids suffered from severe reactive oxygen species stress and depletion of reduced glutathione commensurate with exhaustion of the total glutathione pool. Furthermore, a higher cellular trehalose content was observed as compared to control cultivations, and this trehalose probably acts to enhance a number of stress tolerances of the yeast. PMID:25331461

Guo, Zhongpeng; Olsson, Lisbeth

2014-12-01

17

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

Science.gov (United States)

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

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

2013-11-01

18

Butyric acid from anaerobic fermentation of lignocellulosic biomass hydrolysates by Clostridium sp. strain RPT-4213  

Science.gov (United States)

A novel Clostridium sp. strain RPT-4213 was found producing butyrate under strict anaerobic conditions. This strain produced 9.47 g L-1 butyric acid from MRS media (0.48 g/g glucose). RPT-4213 was also used to ferment dilute acid pretreated hydrolysates including wheat straw (WSH), corn fiber (CFH...

19

Chloroplast-derived enzyme cocktails hydrolyse lignocellulosic biomass and release fermentable sugars  

Digital Repository Infrastructure Vision for European Research (DRIVER)

It is widely recognized that biofuel production from lignocellulosic materials is limited by inadequate technology to efficiently and economically release fermentable sugars from the complex multi-polymeric raw materials. Therefore, endoglucanases, exoglucanase, pectate lyases, cutinase, swollenin, xylanase, acetyl xylan esterase, beta glucosidase and lipase genes from bacteria or fungi were expressed in E. coli or tobacco chloroplasts. A PCR based method was used to clone genes without intro...

Verma, Dheeraj; Kanagaraj, Anderson; Jin, Shuangxia; Singh, Nameirakpam D.; Kolattukudy, Pappachan E.; Daniell, Henry

2010-01-01

20

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

Science.gov (United States)

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 generated during biomass pretreatment and hydrolysis, which induce cellular stress and impair metabolism. Here, we describe the development of a xylose-fermenting S. cerevisiae strain with tolerance to a range of pretreated and hydrolyzed lignocellulose, including Ammonia Fiber Expansion (AFEX)-pretreated corn stover hydrolysate (ACSH). We genetically engineered a hydrolysate-resistant yeast strain with bacterial xylose isomerase and then applied two separate stages of aerobic and anaerobic directed evolution. The emergent S. cerevisiae strain rapidly converted xylose from lab medium and ACSH to ethanol under strict anaerobic conditions. Metabolomic, genetic and biochemical analyses suggested that a missense mutation in GRE3, which was acquired during the anaerobic evolution, contributed toward improved xylose conversion by reducing intracellular production of xylitol, an inhibitor of xylose isomerase. These results validate our combinatorial approach, which utilized phenotypic strain selection, rational engineering and directed evolution for the generation of a robust S. cerevisiae strain with the ability to ferment xylose anaerobically from ACSH. PMID:25222864

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; Tanjore, Deepti; Ong, Irene M.; Li, Haibo; Pohlmann, Edward L.; Serate, Jose; Withers, Sydnor T.; Simmons, Blake A.; Hodge, David B.; Westphall, Michael S.; Coon, Joshua J.; Dale, Bruce E.; Balan, Venkatesh; Keating, David H.; Zhang, Yaoping; Landick, Robert; Gasch, Audrey P.; Sato, Trey K.

2014-01-01

 
 
 
 
21

Chloroplast-derived enzyme cocktails hydrolyse lignocellulosic biomass and release fermentable sugars.  

Science.gov (United States)

It is widely recognized that biofuel production from lignocellulosic materials is limited by inadequate technology to efficiently and economically release fermentable sugars from the complex multi-polymeric raw materials. Therefore, endoglucanases, exoglucanase, pectate lyases, cutinase, swollenin, xylanase, acetyl xylan esterase, beta glucosidase and lipase genes from bacteria or fungi were expressed in Escherichia coli or tobacco chloroplasts. A PCR-based method was used to clone genes without introns from Trichoderma reesei genomic DNA. Homoplasmic transplastomic lines showed normal phenotype and were fertile. Based on observed expression levels, up to 49, 64 and 10, 751 million units of pectate lyases or endoglucanase can be produced annually, per acre of tobacco. Plant production cost of endoglucanase is 3100-fold, and pectate lyase is 1057 or 1480-fold lower than the same recombinant enzymes sold commercially, produced via fermentation. Chloroplast-derived enzymes had higher temperature stability and wider pH optima than enzymes expressed in E. coli. Plant crude-extracts showed higher enzyme activity than E. coli with increasing protein concentration, demonstrating their direct utility without purification. Addition of E. coli extracts to the chloroplast-derived enzymes significantly decreased their activity. Chloroplast-derived crude-extract enzyme cocktails yielded more (up to 3625%) glucose from filter paper, pine wood or citrus peel than commercial cocktails. Furthermore, pectate lyase transplastomic plants showed enhanced resistance to Erwina soft rot. This is the first report of using plant-derived enzyme cocktails for production of fermentable sugars from lignocellulosic biomass. Limitations of higher cost and lower production capacity of fermentation systems are addressed by chloroplast-derived enzyme cocktails. PMID:20070870

Verma, Dheeraj; Kanagaraj, Anderson; Jin, Shuangxia; Singh, Nameirakpam D; Kolattukudy, Pappachan E; Daniell, Henry

2010-04-01

22

Separation of lignocelluloses from spent liquor of NSSC pulping process via adsorption.  

Science.gov (United States)

Hemicelluloses and lignin present in the spent liquor (SL) of neutral sulfite semichemical (NSSC) pulping process can potentially be converted into value-added products such as furfural, hydroxymethylfurfural, levulinic acid, phenols and adhesives. However, the direct conversion of hemicelluloses and lignin of SL into value-added products is uneconomical due to the dilute nature of the SL. To have a feasible downstream process for utilizing lignocelluloses of SL, the lignocelluloses should initially be separated from the SL. In this study, an adsorption process (via applying activated carbon) was considered for isolating the dissolved lignin and hemicelluloses from the SL of an NSSC pulping process. Under the optimal conditions of pH, SL/AC weight ratio, time and temperature of 5.7, 30, 360 min and 30 °C, the maximum lignin and hemicellulose adsorptions were 0.33 and 0.25 g/g on AC. The chemical oxygen demand (COD) and turbidity of the SL were decreased by 11% and 39%, respectively, as a result of lignocellulose adsorption on AC. Also, the incineration behavior of the SL-treated AC was studied with a thermo-gravimetric analysis (TGA). PMID:24565877

Dashtban, Mehdi; Gilbert, Allan; Fatehi, Pedram

2014-04-01

23

Supplementation requirements of brewery's spent grain hydrolysate for biomass and xylitol production by Debaryomyces hansenii CCMI 941.  

Science.gov (United States)

The effect of nutrient supplementation of brewery's spent grain (BSG) hydrolysates was evaluated with respect to biomass and xylitol production by Debaryomyces hansenii. For optimal biomass production, supplementation of full-strength BSG hydrolysates required only phosphate (0.5 g l(-1) KH(2)PO(4)), leading to a biomass yield and productivity of 0.60 g g(-1) monosaccharides and 0.55 g l(-1 )h(-1), respectively. Under the conditions studied, no metabolic products other than CO(2) and biomass were identified. For xylitol production, fourfold and sixfold concentrated hydrolysate-based media were used to assess the supplementation effects. The type of nutrient supplementation modulated the ratio of total polyols/total extracellular metabolites as well as the xylitol/arabitol ratio. While the former varied from 0.8 to 1, the xylitol/arabitol ratio reached a maximum value of 2.6 for yeast extract (YE)-supplemented hydrolysates. The increase in xylitol productivity and yield was related to the increase of the percentage of consumed xylose induced by supplementation. The best xylitol yield and productivity were found for YE supplementation corresponding to 0.55 g g(-1) and 0.36 g l(-1 )h(-1), respectively. In sixfold concentrated hydrolysates, providing that the hydrolysate was supplemented, the levels of xylitol produced were similar or higher than those for arabitol. Xylitol yield exhibited a further increase in the sixfold hydrolysate supplemented with trace elements, vitamins and minerals to 0.65 g g(-1), albeit the xylitol productivity was somewhat lower. The effect of using activated charcoal detoxification in non-supplemented versus supplemented sixfold hydrolysates was also studied. Detoxification did not improve polyols formation, suggesting that the hemicellulose-derived inhibitor levels present in concentrated BSG hydrolysates are well tolerated by D. hansenii. PMID:16520980

Carvalheiro, F; Duarte, L C; Lopes, S; Parajó, J C; Pereira, H; Gírio, F M

2006-08-01

24

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

Science.gov (United States)

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 120°C 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 40°C 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 2.9×10(11)CFU/mL could be obtained. The results provide a foundation for the development of value-added products based on SMS. PMID:21683588

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

2011-09-01

25

SUMO expression shortens the lag phase of Saccharomyces cerevisiae yeast growth caused by complex interactive effects of major mixed fermentation inhibitors found in hot-compressed water-treated lignocellulosic hydrolysate.  

Science.gov (United States)

The complex inhibitory effects of inhibitors present in lignocellulose hydrolysate suppress the ethanol fermentation of Saccharomyces cerevisiae. Although the interactive inhibitory effects play important roles in the actual hydrolysate, few studies have investigated glycolaldehyde, the key inhibitor of hot-compressed water-treated lignocellulose hydrolysate. Given this challenge, we investigated the interactive effects of mixed fermentation inhibitors, including glycolaldehyde. First, we confirmed that glycolaldehyde was the most potent inhibitor in the hydrolysate and exerted interactive inhibitory effects in combination with major inhibitors. Next, through genome-wide analysis and megavariate data modeling, we identified SUMOylation as a novel potential mechanism to overcome the combinational inhibitory effects of fermentation inhibitors. Indeed, overall SUMOylation was increased and Pgk1, which produces an ATP molecule in glycolysis by substrate-level phosphorylation, was SUMOylated and degraded in response to glycolaldehyde. Augmenting the SUMO-dependent ubiquitin system in the ADH1-expressing strain significantly shortened the lag phase of growth, released cells from G2/M arrest, and improved energy status and glucose uptake in the inhibitor-containing medium. In summary, our study was the first to establish SUMOylation as a novel platform for regulating the lag phase caused by complex fermentation inhibitors. PMID:25359478

Jayakody, Lahiru N; Kadowaki, Masafumi; Tsuge, Keisuke; Horie, Kenta; Suzuki, Akihiro; Hayashi, Nobuyuki; Kitagaki, Hiroshi

2015-01-01

26

Engineering yeast tolerance to inhibitory lignocellulosic biomass  

Digital Repository Infrastructure Vision for European Research (DRIVER)

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...

Cunha, Joana; Aguiar, Tatiana Quinta; Mendes, D.; Pereira, Francisco B.; Domingues, Luci?lia

2013-01-01

27

The chemical nature of phenolic compounds determines their toxicity and induces distinct physiological responses in Saccharomyces cerevisiae in lignocellulose hydrolysates  

Science.gov (United States)

We investigated the severity of the inhibitory effects of 13 phenolic compounds usually found in spruce hydrolysates (4-hydroxy-3-methoxycinnamaldehyde, homovanilyl alcohol, vanillin, syringic acid, vanillic acid, gallic acid, dihydroferulic acid, p-coumaric acid, hydroquinone, ferulic acid, homovanillic acid, 4-hydroxybenzoic acid and vanillylidenacetone). The effects of the selected compounds on cell growth, biomass yield and ethanol yield were studied and the toxic concentration threshold was defined for each compound. Using Ethanol Red, the popular industrial strain of Saccharomyces cerevisiae, we found the most toxic compound to be 4-hydroxy-3-methoxycinnamaldehyde which inhibited growth at a concentration of 1.8 mM. We also observed that toxicity did not generally follow a trend based on the aldehyde, acid, ketone or alcohol classification of phenolic compounds, but rather that other structural properties such as additional functional groups attached to the compound may determine its toxicity. Three distinctive growth patterns that effectively clustered all the compounds involved in the screening into three categories. We suggest that the compounds have different cellular targets, and that. We suggest that the compounds have different cellular targets and inhibitory mechanisms in the cells, also compounds who share similar pattern on cell growth may have similar inhibitory effect and mechanisms of inhibition. PMID:24949277

2014-01-01

28

Sophorolipid Production from Biomass Hydrolysates.  

Science.gov (United States)

Although extensive research has been conducted on producing sophorolipids using Candida (Starmerella) bombicola from pure sugars and various oil sources, production of this biosurfactant has not been evaluated when cells are cultivated in lignocellulosic hydrolysates. Here, we report for the first time that C. bombicola is capable of producing sophorolipids on hydrolysates derived from sweet sorghum bagasse and corn fiber. Without oil supplementation, a sophorolipid concentration of 3.6 and 1.0 g/L was detected from cultures with bagasse and corn fiber hydrolysates, respectively. With the addition of soybean oil at 100 g/L, the yield of sophorolipids from these two hydrolysates in the same order was 84.6 and 15.6 g/L. Surprisingly, C. bombicola consumed all monomeric sugars and nonsugar compounds in the hydrolysates, and cultures with bagasse hydrolysates had higher yield of sophorolipids than those from a standard medium which contained pure glucose at the same concentration. PMID:25475889

Samad, Abdul; Zhang, Ji; Chen, Da; Liang, Yanna

2014-12-01

29

Ethanol production from lignocellulosic materials. Fermentation and on-line analysis  

Energy Technology Data Exchange (ETDEWEB)

The fermentation performance of bacteria, yeast and fungi was investigated in lignocellulosic hydrolysates with the aim of finding microorganisms which both withstand the inhibitors and that have the ability to ferment pentoses. Firstly, the performance of Saccharomyces cidri, Saccharomyces cerevisiae, Lactobacillus brevis, Lactococcus lactis ssp lactis, Escherichia coli and Zymomonas mobilis was investigated in spent sulphite liquor and enzymatic hydrolysate of steam-pretreated willow. Secondly, the performance of natural and recombinant E. coli, Pichia stipitis, recombinant S. cerevisiae, S. cerevisiae in combination with xylose isomerase and Fusarium oxysporum was investigated in a xylose-rich acid hydrolysate of corn cob. Recombinant E. coli was the best alternative for fermentation of lignocellulosic hydrolysates, giving both high yields and productivities. The main drawback was that detoxification was necessary. The kinetics of the fermentation with recombinant E. coli KO11 was investigated in the condensate of steam-pretreated willow. A cost analysis of the ethanol production from willow was made, which predicted an ethanol production cost of 3.9 SEK/l for the pentose fermentation. The detoxification cost constituted 22% of this cost. The monitoring of three monosaccharides and ethanol in lignocellulosic hydro lysates is described. The monosaccharides were determined using immobilized pyranose oxidase in an on-line amperometric analyser. Immobilization and characterization of pyranose oxidase from Phanerochaete chrysosporium is also described. The ethanol was monitored on-line using a micro dialysis probe as an in situ sampling device. The dialysate components were then separated in a column liquid chromatographic system and the ethanol was selectively detected by an amperometric alcohol bio sensor. The determinations with on-line analysis methods agreed well with off-line methods. 248 refs, 4 figs, 12 tabs

Olsson, L.

1994-04-01

30

Comparison of methods for detoxification of spruce hydrolysate for bacterial cellulose production  

Digital Repository Infrastructure Vision for European Research (DRIVER)

BACKGROUND: Bacterial cellulose (BC) is a nanostructured material with unique properties and wide applicability. In order to decrease the production cost of bacterial cellulose, lignocellulose-based media have considerable potential as alternative cost-effective feedstocks. However, pretreatment and enzymatic hydrolysis of lignocellulose to sugars also generate fermentation inhibitors. Detoxification of lignocellulosic hydrolysates is needed to achieve efficient production of BC. In this inve...

Guo, Xiang; Cavka, Adnan; Jo?nsson, Leif J.; Hong, Feng

2013-01-01

31

Lignocellulosic feedstock resource assessment  

Energy Technology Data Exchange (ETDEWEB)

In 1997, the National Renewable Energy Laboratory (NREL) undertook a national biomass resource assessment to address a lack of basic resource information for scientists, industry, and policy-makers. The objective of this resource assessment was to describe the state-level distribution, quantity and market value of lignocellulosic feedstocks for ethanol production in the United States. Lignocellulosic feedstocks, derived from plant materials, are composed primarily of cellulose, hemicellulose, and lignin. Cellulose and hemicellulose are polymers of simple sugars that can be chemically fermented to produce ethanol. Lignin plays a role in binding cellulose and hemicellulose together in plant cell walls. This study focused on lignocellulosic by-products of agriculture, food processing, forest products industry, and consumers. The United States generates 306 million metric tons (dry weight) of lignocellulosic materials annually that could be used to manufacture ethanol. The bulk of this potential feedstock supply is made up of agricultural residues left following crop harvesting, such as corn stover. Corn stover makes up 70 percent of the total biomass resource. If agricultural residues are used for ethanol production, the price paid for agricultural residues will have to meet or exceed their current soil nutrient and animal fodder values. Food processing residues such as corn gluten feed and meal, distillers' dried grains, and spent brewer's grains are used as animal feed additives, which makes them high in cost in relation to other feedstocks. Forest products residues are mostly used for fuel, pulp, animal bedding, or mulch. The unutilized portion of these residues may be available for ethanol production. Recycled paper, sugarcane bagasse, rice straw, paper sludge, and urban tree residue show potential for use as ethanol feedstocks due to their low cost. (author)

Rooney, T.E.; Haase, S.G. [McNeil Technologies, Golden, CO (United States); Wiselogel, A.E. [National Renewable Energy Laboratory, Golden, CO (United States)

1999-07-01

32

Egg protein hydrolysates  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The present invention provides egg-protein hydrolysates with DPP-IV inhibitory activity which are particularly suited for the treatment of diabetes. Particularly advantageous is to use hydrolysate of lysozyme for the treatment of diabetes.

Amerongen, A.; Beelen, M. J. C.; Wolbers, L. A. M.; Gilst, W. H.; Buikema, J. H.; Nelissen, J. W. P. M.

2009-01-01

33

Grass Lignocellulose  

Science.gov (United States)

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.

Akin, Danny E.

34

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

Science.gov (United States)

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

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

2014-10-15

35

Selective suppression of bacterial contaminants by process conditions during lignocellulose based yeast fermentations  

Directory of Open Access Journals (Sweden)

Full Text Available Abstract Background Contamination of bacteria in large-scale yeast fermentations is a serious problem and a threat to the development of successful biofuel production plants. Huge research efforts have been spent in order to solve this problem, but additional ways must still be found to keep bacterial contaminants from thriving in these environments. The aim of this project was to develop process conditions that would inhibit bacterial growth while giving yeast a competitive advantage. Results Lactic acid bacteria are usually considered to be the most common contaminants in industrial yeast fermentations. Our observations support this view but also suggest that acetic acid bacteria, although not so numerous, could be a much more problematic obstacle to overcome. Acetic acid bacteria showed a capacity to drastically reduce the viability of yeast. In addition, they consumed the previously formed ethanol. Lactic acid bacteria did not show this detrimental effect on yeast viability. It was possible to combat both types of bacteria by a combined addition of NaCl and ethanol to the wood hydrolysate medium used. As a result of NaCl + ethanol additions the amount of viable bacteria decreased and yeast viability was enhanced concomitantly with an increase in ethanol concentration. The successful result obtained via addition of NaCl and ethanol was also confirmed in a real industrial ethanol production plant with its natural inherent yeast/bacterial community. Conclusions It is possible to reduce the number of bacteria and offer a selective advantage to yeast by a combined addition of NaCl and ethanol when cultivated in lignocellulosic medium such as wood hydrolysate. However, for optimal results, the concentrations of NaCl + ethanol must be adjusted to suit the challenges offered by each hydrolysate.

Albers Eva

2011-12-01

36

Electricity generation by microbial fuel cells fuelled with wheat straw hydrolysate  

International Nuclear Information System (INIS)

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.

37

Cofactor Dependence in Furan Reduction by Saccharomyces cerevisiae in Fermentation of Acid-Hydrolyzed Lignocellulose  

Digital Repository Infrastructure Vision for European Research (DRIVER)

A decreased fermentation rate due to inhibition is a significant problem for economic conversion of acid-pretreated lignocellulose hydrolysates to ethanol, since the inhibition gives rise to a requirement for separate detoxification steps. Together with acetic acid, the sugar degradation products furfural and 5-hydroxymethyl furfural are the inhibiting compounds found at the highest concentrations in hydrolysates. These aldehydes have been shown to affect both the specific growth rate and the...

Nilsson, Anneli; Gorwa-grauslund, Marie F.; Hahn-ha?gerdal, Ba?rbel; Lide?n, Gunnar

2005-01-01

38

Ethanol production from lignocellulose  

Energy Technology Data Exchange (ETDEWEB)

This invention presents a method of improving enzymatic degradation of lignocellulose, as in the production of ethanol from lignocellulosic material, through the use of ultrasonic treatment. The invention shows that ultrasonic treatment reduces cellulase requirements by 1/3 to 1/2. With the cost of enzymes being a major problem in the cost-effective production of ethanol from lignocellulosic material, this invention presents a significant improvement over presently available methods.

Ingram, Lonnie O. (Gainesville, FL); Wood, Brent E. (Gainesville, FL)

2001-01-01

39

Electricity generation by microbial fuel cells fuelled with wheat straw hydrolysate  

DEFF Research Database (Denmark)

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.

Thygesen, Anders; Poulsen, Finn Willy

2011-01-01

40

Bioprocessing of bagasse hydrolysate for ethanol and xylitol production using thermotolerant yeast.  

Science.gov (United States)

Fermentation of xylose-rich and glucose-rich bagasse hydrolysates, obtained from the two-stage acid hydrolysis was studied using the thermotolerant yeast Kluyveromyces sp. IIPE453. The yeast could grow on xylose-rich hydrolysate at 50 °C with the dry cell weight, cell mass yield and maximum specific growth rate of 5.35 g l(-1), 0.58 g g(-1) and 0.13 h(-1), respectively. The yeast was found to be very promising for ethanol as well as xylitol production from the sugars obtained from the lignocellulosic biomass. Batch fermentations of xylose-rich and glucose-rich hydrolysates yielded 0.61 g g(-1) xylitol and 0.43 g g(-1) ethanol in the broth, respectively based on the sugars present in the hydrolysate. Overall ethanol yield of 165 g (210 ml) and 183 g xylitol per kg of bagasse was obtained, when bagasse hydrolysate was used as a substrate. Utilization of both the glucose and xylose sugars makes the process most economical by producing both ethanol and xylitol based on biorefinery concept. On validating the experimental data of ethanol fermentation, the modified Luong kinetic model for product inhibition as well as inhibition due to inhibitory compounds present in hydrolysate, the model was found to be the best fit for ethanol formation from bagasse hydrolysate using Kluyveromyces sp. IIPE453. PMID:25090978

Kumar, Sachin; Dheeran, Pratibha; Singh, Surendra P; Mishra, Indra M; Adhikari, Dilip K

2015-01-01

 
 
 
 
41

Controlled pilot development unit-scale fed-batch cultivation of yeast on spruce hydrolysates.  

Science.gov (United States)

Yeast production on hydrolysate is a likely process solution in large-scale ethanol production from lignocellulose. The hydrolysate will be available on site, and the yeast has furthermore been shown to acquire an increased inhibitor tolerance when cultivated on hydrolysate. However, due to over-flow metabolism and inhibition, efficient yeast production on hydrolysate can only be achieved by well-controlled substrate addition. In the present work, a method was developed for controlled addition of hydrolysate to PDU (process development unit)-scale aerobic fed-batch cultivations of Saccharomyces cerevisiae TMB 3000. A feed rate control strategy, which maintains the ethanol concentration at a low constant level, was adapted to process-like conditions. The ethanol concentration was obtained from on-line measurements of the ethanol mole fraction in the exhaust gas. A computer model of the system was developed to optimize control performance. Productivities, biomass yields, and byproduct formation were evaluated. The feed rate control worked satisfactorily and maintained the ethanol concentration close to the setpoint during the cultivations. Biomass yields of 0.45 g/g were obtained on added hexoses during cultivation on hydrolysate and of 0.49 g/g during cultivation on a synthetic medium with glucose as the carbon source. Exponential growth was achieved with a specific growth rate of 0.18 h-1 during cultivation on hydrolysate and 0.22 h-1 during cultivation on glucose. PMID:17330957

Rudolf, Andreas; Lequeux, Gaspard; Lidén, Gunnar

2007-01-01

42

Lipid production by Cryptococcus curvatus on hydrolysates derived from corn fiber and sweet sorghum bagasse following dilute acid pretreatment.  

Science.gov (United States)

Corn fiber and sweet sorghum bagasse (SSB) are both pre-processed lignocellulosic materials that can be used to produce liquid biofuels. Pretreatment using dilute sulfuric acid at a severity factor of 1.06 and 1.02 released 83.2 and 86.5 % of theoretically available sugars out of corn fiber and SSB, respectively. The resulting hydrolysates derived from pretreatment of SSB at SF of 1.02 supported growth of Cryptococcus curvatus well. In 6 days, the dry cell density reached 10.8 g/l with a lipid content of 40 % (w/w). Hydrolysates from corn fiber, however, did not lead to any significant cell growth even with addition of nutrients. In addition to consuming glucose, xylose, and arabinose, C. curvatus also utilized formic acid, acetic acid, 4-hydroxymethylfurfural, and levulinic acid for growth. Thus, C. curvatus appeared to be an excellent yeast strain for producing lipids from hydrolysates developed from lignocellulosic feedstocks. PMID:24928546

Liang, Yanna; Jarosz, Kimberly; Wardlow, Ashley T; Zhang, Ji; Cui, Yi

2014-08-01

43

Protein hydrolysates in sports nutrition  

Digital Repository Infrastructure Vision for European Research (DRIVER)

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 ...

Manninen Anssi H

2009-01-01

44

Protein hydrolysates in sports nutrition  

Directory of Open Access Journals (Sweden)

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.

Manninen Anssi H

2009-09-01

45

21 CFR 102.22 - Protein hydrolysates.  

Science.gov (United States)

...2010-04-01 2010-04-01 false Protein hydrolysates. 102.22 Section 102.22...Nonstandardized Foods § 102.22 Protein hydrolysates. The common or usual name of a protein hydrolysate shall be specific to the...

2010-04-01

46

Ethanol production using a soy hydrolysate-based medium or a yeast autolysate-based medium  

Energy Technology Data Exchange (ETDEWEB)

This invention presents a method for the production of ethanol that utilizes a soy hydrolysate-based nutrient medium or a yeast autolysate-based medium nutrient medium in conjunction with ethanologenic bacteria and a fermentable sugar for the cost-effective production of ethanol from lignocellulosic biomass. The invention offers several advantages over presently available media for use in ethanol production, including consistent quality, lack of toxins and wide availability.

Ingram, Lonnie O. (Gainesville, FL)

2000-01-01

47

Effect of lignocellulose-derived inhibitors on growth and hydrogen production by Thermoanaerobacterium thermosaccharolyticum W16  

Energy Technology Data Exchange (ETDEWEB)

In the process of producing H{sub 2} from lignocellulosic materials, inhibitory compounds could be potentially formed during pre-treatment. This work experimentally investigated the effect of lignocellulose-derived inhibitors on growth and hydrogen production by Thermoanaerobacterium thermosaccharolyticum W16. Representative compounds presented in corn stover acid hydrolysate were added in various concentrations, individually or in various combinations and subsequently inhibitions on growth and H{sub 2} production were quantified. Acetate sodium was not inhibitory to T. thermosaccharolyticum W16, rather than it was stimulatory to the growth and H{sub 2} production. Alternatively, furfural, hydroxymethylfurfural (HMF), vanillin and syringaldehyde were potent inhibitors of growth and hydrogen production even though these compounds showed inhibitory effect depending on their concentrations. Synergistic inhibitory effects were exhibited in the introduction of combinations of inhibitors to the medium and in hydrolysate with concentrated inhibitors. Fermentation results from hydrolysates revealed that to increase the efficiency of this bioprocess from corn stover hydrolysate, the inhibitory compounds concentration must be reduced to the levels present in the raw hydrolysate. (author)

Cao, Guang-Li; Ren, Nan-Qi; Wang, Ai-Jie; Guo, Wan-Qian; Xu, Ji-Fei; Liu, Bing-Feng [State Key Lab of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090 (China)

2010-12-15

48

Succinic acid production from corn cob hydrolysates by genetically engineered Corynebacterium glutamicum.  

Science.gov (United States)

Corynebacterium glutamicum wild type lacks the ability to utilize the xylose fractions of lignocellulosic hydrolysates. In the present work, we constructed a xylose metabolic pathway in C. glutamicum by heterologous expression of the xylA and xylB genes coming from Escherichia coli. Dilute-acid hydrolysates of corn cobs containing xylose and glucose were used as a substrate for succinic acid production by recombinant C. glutamicum NC-2. The results indicated that the available activated charcoal pretreatment in dilute-acid hydrolysates of corn cobs could be able to overcome the inhibitory effect in succinic acid production. Succinic acid was shown to be efficiently produced from corn cob hydrolysates (55 g l(-1) xylose and 4 g l(-1) glucose) under oxygen deprivation with addition of sodium carbonate. Succinic acid concentration reached 40.8 g l(-1) with a yield of 0.69 g g(-1) total sugars within 48 h. It was the first report of succinic acid production from corn cob hydrolysates by metabolically engineered C. glutamicum. This study suggested that dilute-acid hydrolysates of corn cobs may be an alternative substrate for the efficient production of succinic acid by C. glutamicum. PMID:24078255

Wang, Chen; Zhang, Hengli; Cai, Heng; Zhou, Zhihui; Chen, Yilu; Chen, Yali; Ouyang, Pingkai

2014-01-01

49

Pre-treatment of ligno-cellulose with biological acid recycling (the Biosulfurol process)  

Digital Repository Infrastructure Vision for European Research (DRIVER)

A biomass pretreatment process is being developed based on contacting ligno-cellulosic biomass with 70% sulphuric acid and subsequent hydrolysis by adding water. In this process, the hydrolysate can be fermented yielding ethanol, while the sulphuric acid is partly recovered by anion-selective membranes before the fermentation process, and partly via biological sulphate reduction in the anaerobic wastewater treatment plant. The produced sulphide is recovered as H2S gas and chemically converted...

Groenestijn, J. W.; Hazewinkel, J. H. O.; Bakker, R. R.

2008-01-01

50

Mutants of the pentose-fermenting yeast Pachysolen tannophilus tolerant to hardwood spent sulfite liquor and acetic acid.  

Science.gov (United States)

A strain development program was initiated to improve the tolerance of the pentose-fermenting yeast Pachysolen tannophilus to inhibitors in lignocellulosic hydrolysates. Several rounds of UV mutagenesis followed by screening were used to select for mutants of P. tannophilus NRRL Y2460 with improved tolerance to hardwood spent sulfite liquor (HW SSL) and acetic acid in separate selection lines. The wild type (WT) strain grew in 50 % (v/v) HW SSL while third round HW SSL mutants (designated UHW301, UHW302 and UHW303) grew in 60 % (v/v) HW SSL, with two of these isolates (UHW302 and UHW303) being viable and growing, respectively, in 70 % (v/v) HW SSL. In defined liquid media containing acetic acid, the WT strain grew in 0.70 % (w/v) acetic acid, while third round acetic acid mutants (designated UAA301, UAA302 and UAA303) grew in 0.80 % (w/v) acetic acid, with one isolate (UAA302) growing in 0.90 % (w/v) acetic acid. Cross-tolerance of HW SSL-tolerant mutants to acetic acid and vice versa was observed with UHW303 able to grow in 0.90 % (w/v) acetic acid and UAA302 growing in 60 % (v/v) HW SSL. The UV-induced mutants retained the ability to ferment glucose and xylose to ethanol in defined media. These mutants of P. tannophilus are of considerable interest for bioconversion of the sugars in lignocellulosic hydrolysates to ethanol. PMID:24122119

Harner, Nicole K; Bajwa, Paramjit K; Habash, Marc B; Trevors, Jack T; Austin, Glen D; Lee, Hung

2014-01-01

51

Ethanol production from wood hydrolysate using genetically engineered Zymomonas mobilis  

Energy Technology Data Exchange (ETDEWEB)

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.)

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

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Ethanol production from wood hydrolysate using genetically engineered Zymomonas mobilis.  

Science.gov (United States)

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(-1). PMID:22573268

Yanase, Hideshi; Miyawaki, Hitoshi; Sakurai, Mitsugu; Kawakami, Akinori; Matsumoto, Mari; Haga, Kenji; Kojima, Motoki; Okamoto, Kenji

2012-06-01

53

Complex physiology and compound stress responses during fermentation of alkali-pretreated corn stover hydrolysate by an Escherichia coli ethanologen.  

Science.gov (United States)

The physiology of ethanologenic Escherichia coli grown anaerobically in alkali-pretreated plant hydrolysates is complex and not well studied. To gain insight into how E. coli responds to such hydrolysates, we studied an E. coli K-12 ethanologen fermenting a hydrolysate prepared from corn stover pretreated by ammonia fiber expansion. Despite the high sugar content (?6% glucose, 3% xylose) and relatively low toxicity of this hydrolysate, E. coli ceased growth long before glucose was depleted. Nevertheless, the cells remained metabolically active and continued conversion of glucose to ethanol until all glucose was consumed. Gene expression profiling revealed complex and changing patterns of metabolic physiology and cellular stress responses during an exponential growth phase, a transition phase, and the glycolytically active stationary phase. During the exponential and transition phases, high cell maintenance and stress response costs were mitigated, in part, by free amino acids available in the hydrolysate. However, after the majority of amino acids were depleted, the cells entered stationary phase, and ATP derived from glucose fermentation was consumed entirely by the demands of cell maintenance in the hydrolysate. Comparative gene expression profiling and metabolic modeling of the ethanologen suggested that the high energetic cost of mitigating osmotic, lignotoxin, and ethanol stress collectively limits growth, sugar utilization rates, and ethanol yields in alkali-pretreated lignocellulosic hydrolysates. PMID:22389370

Schwalbach, Michael S; Keating, David H; Tremaine, Mary; Marner, Wesley D; Zhang, Yaoping; Bothfeld, William; Higbee, Alan; Grass, Jeffrey A; Cotten, Cameron; Reed, Jennifer L; da Costa Sousa, Leonardo; Jin, Mingjie; Balan, Venkatesh; Ellinger, James; Dale, Bruce; Kiley, Patricia J; Landick, Robert

2012-05-01

54

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

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 w...

Penglin Li; Xiaoling Miao; Rongxiu Li; Jianjiang Zhong

2011-01-01

55

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

Directory of Open Access Journals (Sweden)

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.

DonnaMBates

2014-08-01

56

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

Science.gov (United States)

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(P)H, 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. PMID:25177315

Keating, David H.; Zhang, Yaoping; Ong, Irene M.; McIlwain, Sean; Morales, Eduardo H.; Grass, Jeffrey A.; Tremaine, Mary; Bothfeld, William; Higbee, Alan; Ulbrich, Arne; Balloon, Allison J.; Westphall, Michael S.; Aldrich, Josh; Lipton, Mary S.; Kim, Joonhoon; Moskvin, Oleg V.; Bukhman, Yury V.; Coon, Joshua J.; Kiley, Patricia J.; Bates, Donna M.; Landick, Robert

2014-01-01

57

The chemistry involved in the steam treatment of lignocellulosic materials  

Directory of Open Access Journals (Sweden)

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.

Ramos Luiz Pereira

2003-01-01

58

The chemistry involved in the steam treatment of lignocellulosic materials  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english 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 m [...] ethods 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.

Luiz Pereira, Ramos.

2003-12-01

59

Oleaginous fungal lipid fermentation on combined acid- and alkali-pretreated corn stover hydrolysate for advanced biofuel production.  

Science.gov (United States)

A combined hydrolysis process, which first mixed dilute acid- and alkali-pretreated corn stover at a 1:1 (w/w) ratio, directly followed by enzymatic saccharification without pH adjustment, has been developed in this study in order to minimize the need of neutralization, detoxification, and washing during the process of lignocellulosic biofuel production. The oleaginous fungus Mortierella isabellina was selected and applied to the combined hydrolysate as well as a synthetic medium to compare fungal lipid accumulation and biodiesel production in both shake flask and 7.5L fermentor. Fungal cultivation on combined hydrolysate exhibited comparable cell mass and lipid yield with those from synthetic medium, indicating that the integration of combined hydrolysis with oleaginous fungal lipid fermentation has great potential to improve performance of advanced lignocellulosic biofuel production. PMID:24768942

Ruan, Zhenhua; Zanotti, Michael; Archer, Steven; Liao, Wei; Liu, Yan

2014-07-01

60

Biogas from lignocellulosic biomass  

Energy Technology Data Exchange (ETDEWEB)

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.

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

2012-01-15

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

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...

Marton, J. M.; Felipe, M. G. A.; Silva, J. B. Almeida E.; Pessoa Ju?nior, A.

2006-01-01

62

Protein Hydrolysates/Peptides in Animal Nutrition  

Science.gov (United States)

The use of protein hydrolysates as an important nutrient for growth and maintenance has been increasing in animal nutrition. Although animal proteins and protein hydrolysates are widely used however, recently vegetable protein hydrolysates are gaining importance. This chapter reviews the use of protein hydrolysates developed by enzyme hydrolysis and by solid state fermentation process in animal nutrition especially for piglets and compares it with the standard products such as plasma and fishmeal.

McCalla, Jeff; Waugh, Terry; Lohry, Eric

63

Efficient production of 2,3-butanediol from corn stover hydrolysate by using a thermophilic Bacillus licheniformis strain.  

Science.gov (United States)

In this study, a thermophilic Bacillus licheniformis strain X10 was newly isolated for 2,3-butanediol (2,3-BD) production from lignocellulosic hydrolysate. Strain X10 could utilize glucose and xylose simultaneously without carbon catabolite repression. In addition, strain X10 possesses high tolerance to fermentation inhibitors including furfural, vanillin, formic acid, and acetic acid. In a fed-batch fermentation, 74.0g/L of 2,3-BD was obtained from corn stover hydrolysate, with a productivity of 2.1g/Lh and a yield of 94.6%. Thus, this thermophilic B. licheniformis strain is a candidate for the development of efficient industrial production of 2,3-BD from corn stover hydrolysate. PMID:25151068

Li, Lixiang; Li, Kun; Wang, Kai; Chen, Chao; Gao, Chao; Ma, Cuiqing; Xu, Ping

2014-10-01

64

LIGNOCELLULOSE NANOCOMPOSITE CONTAINING COPPER SULFIDE  

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Copper sulfide-containing lignocellulose nanocomposites with improved electroconductivity were obtained. Two methods for preparing the copper sulfide lignocellulose nanocomposites were developed. An optimization of the parameters for obtaining of the nanocomposites with respect to obtaining improved electroconductivity, economy, and lower quantities and concentration of copper and sulfur ions in waste waters was conducted. The mechanisms and schemes of delaying and subsequent connection of co...

Sanchi Nenkova; Peter Velev; Mirela Dragnevska; Diyana Nikolova; Kiril Dimitrov

2011-01-01

65

Methods for degrading lignocellulosic materials  

Science.gov (United States)

The present invention relates to methods for degrading a lignocellulosic material, comprising: treating the lignocellulosic material with an effective amount of one or more cellulolytic enzymes in the presence of at least one surfactant selected from the group consisting of a secondary alcohol ethoxylate, fatty alcohol ethoxylate, nonylphenol ethoxylate, tridecyl ethoxylate, and polyoxyethylene ether, wherein the presence of the surfactant increases the degradation of lignocellulosic material compared to the absence of the surfactant. The present invention also relates to methods for producing an organic substance, comprising: (a) saccharifying a lignocellulosic material with an effective amount of one or more cellulolytic enzymes in the presence of at least one surfactant selected from the group consisting of a secondary alcohol ethoxylate, fatty alcohol ethoxylate, nonylphenol ethoxylate, tridecyl ethoxylate, and polyoxyethylene ether, wherein the presence of the surfactant increases the degradation of lignocellulosic material compared to the absence of the surfactant; (b) fermenting the saccharified lignocellulosic material of step (a) with one or more fermenting microorganisms; and (c) recovering the organic substance from the fermentation.

Vlasenko, Elena (Davis, CA); Cherry, Joel (Davis, CA); Xu, Feng (Davis, CA)

2011-05-17

66

Pervaporation behavior and integrated process for concentrating lignocellulosic ethanol through polydimethylsiloxane (PDMS) membrane.  

Science.gov (United States)

The effects of by-products from ethanol fermentation and hydrolysates of lignocelluloses on ethanol diffusion through polydimethylsiloxane (PDMS) membranes with/without silicalite-1 were investigated. A pervaporation process was integrated with lignocellulosic fermentation to concentrate bioethanol using bare PDMS membranes. Results showed that yeasts, solid particles, and salts increased ethanol flux and selectivity through the membranes (PDMS with/without silicalite-1), whereas glucose exerted negative effects on the performance. On bare PDMS membrane, the performance was not obviously affected by the existence of aliphatic acids. However, on PDMS-silicalite-1 membrane, a remarkable decrease in ethanol selectivity and a rapid growth of total flux in the presence of aliphatic acids were observed. These phenomena were due to the interaction of acids with silanol (Si-OH) groups to break the dense membrane surface. On the PDMS membranes with/without silicalite-1, degradation products of lignocellulosic hydrolysates such as furfural and hydroxyacetone slightly influenced separation performance. These results revealed that an integrated process can effectively eliminate product inhibition, improve ethanol productivity, and enhance the glucose conversion rate. PMID:23732286

Chen, Jingwen; Zhang, Hongman; Wei, Ping; Zhang, Lin; Huang, He

2014-02-01

67

Comparison of methods for detoxification of spruce hydrolysate for bacterial cellulose production  

Science.gov (United States)

Background Bacterial cellulose (BC) is a nanostructured material with unique properties and wide applicability. In order to decrease the production cost of bacterial cellulose, lignocellulose-based media have considerable potential as alternative cost-effective feedstocks. However, pretreatment and enzymatic hydrolysis of lignocellulose to sugars also generate fermentation inhibitors. Detoxification of lignocellulosic hydrolysates is needed to achieve efficient production of BC. In this investigation, different methods for detoxification of spruce hydrolysate prior to production of BC were compared with respect to effects on potential inhibitors and fermentable sugars, sugar consumption, BC yield, and cell viability. The objectives were to identify efficient detoxification methods and to achieve a better understanding of the role played by different inhibitors in lignocellulosic hydrolysates. Results In a first series of experiments, the detoxification methods investigated included treatments with activated charcoal, alkali [sodium hydroxide, calcium hydroxide (overliming), and ammonium hydroxide], anion and cation ion-exchange resins, and reducing agents (sodium sulfite and sodium dithionite). A second series of detoxification experiments included enzymatic treatments (laccase and peroxidase). The potential inhibitors studied included aliphatic acids, furan aldehydes, and phenolic compounds. The best effects in the first series of detoxification experiments were achieved with activated charcoal and anion exchanger. After detoxification with activated charcoal the BC yield was 8.2 g/L, while it was 7.5 g/L in a reference medium without inhibitors. Treatments with anion exchanger at pH 10 and pH 5.5 gave a BC yield of 7.9 g/L and 6.3 g/L, respectively. The first series of experiments suggested that there was a relationship between the BC yield and phenolic inhibitors. Therefore, the second series of detoxification experiments focused on treatments with phenol-oxidizing enzymes. The BC yield in the laccase-detoxified hydrolysate reached 5.0-5.5 g/L after 14 days cultivation, which demonstrated the important inhibitory role played by phenolic compounds. Conclusions The investigation shows that detoxification methods that efficiently remove phenolics benefit bacterial growth and BC production. Negative effects of salts could not be excluded and the osmotolerance of Gluconacetobacter xylinus needs to be further investigated in the future. Combinations of detoxification methods that efficiently decrease the concentration of inhibitors remain as an interesting option. PMID:24119691

2013-01-01

68

Bioconversion of corncob acid hydrolysate into microbial oil by the oleaginous yeast Lipomyces starkeyi.  

Science.gov (United States)

For the first time, corncob acid hydrolysate was used for microbial oil production by the oleaginous yeast Lipomyces starkeyi. After hydrolysis by dilute sulfuric acid, corncob could turn into an acid hydrolysate with a sugar concentration of about 42.3 g/L. Detoxified by overliming and absorption with activated carbon, the corncob hydrolysate could be used by L. starkeyi efficiently that a total biomass of 17.2 g/L with a lipid content of 47.0 % (corresponding to a lipid yield of 8.1 g/L) and a lipid coefficient of 20.9 could be obtained after cultivation on the corncob hydrolysate for 8 days. Therefore, L. starkeyi is a promising strain for microbial oil production from lignocellulosic biomass. Glucose and xylose were used by L. starkeyi simultaneously during lipid fermentation while arabinose could not be utilized by it. Besides, the lipid composition of L. starkeyi was similar to that of vegetable oils; thus, it is a promising feedstock for biodiesel production. PMID:24343368

Huang, Chao; Chen, Xue-Fang; Yang, Xiao-Yan; Xiong, Lian; Lin, Xiao-Qing; Yang, Juan; Wang, Bo; Chen, Xin-De

2014-02-01

69

Sugar cane bagasse as feedstock for second generation ethanol production: Part II: Hemicellulose hydrolysate fermentability  

Scientific Electronic Library Online (English)

Full Text Available SciELO Chile | Language: English Abstract in english Sugar cane bagasse is produced in Brazil as waste of the sugar and ethanol industries. This lignocellulosic material is a potential source for second-generation ethanol production; however a pretreatment stage is essential, which aims at removing the hemicellulose component by disorganizing the lign [...] ocellulosic complex. In this work sugar cane bagasse was pretreated by diluted acid hydrolysis resulting in xylose-rich hydrolysates, which could be fermented to ethanol by a strain of the yeast Pichia stipitis. Statistical approach was used to investigate the effects of factors associated with the diluted acid hydrolysis process (acid concentration, solid:liquid ratio and time of exposure) on the fermentability of different hydrolysates. The statistical analysis was useful for determining the effects of the individual factors and their interactions on the response variables. An acid concentration of 1.09% (v/v), a solid:liquid ratio of 1:2.8 (g:ml), and an exposure time of 27 min were established and validated as the optimum pretreatment conditions for ethanol production from hemicellulose hydrolysates of sugar cane bagasse. Under these conditions, a hydrolysate with 50 g/l of xylose, 6.04 g/l of acetic acid, 0.55 g/l of hydroxylmethylfurfural and 0.09 g/l of furfural was obtained and its fermentation yielded roughly 20 g/l of ethanol in 40 hrs.

Gabriel J. Vargas, Betancur; Nei, Pereira Jr.

2010-09-15

70

Xylanase production by Burkholderia sp. DMAX strain under solid state fermentation using distillery spent wash.  

Science.gov (United States)

Xylanase production by a newly isolated strain of Burkholderia sp. was studied under solid state fermentation using anaerobically treated distillery spent wash. Response surface methodology (RSM) involving Box-Behnken design was employed for optimizing xylanase production. The interactions between distillery effluent concentration, initial pH, moisture ratio and inoculum size were investigated and modeled. Under optimized conditions, xylanase production was found to be in the range of 5200-5600 U/g. The partially purified enzyme recovered after ammonium sulphate fractionation showed maximum activity at 50 degrees C and pH 8.6. Kinetic parameters like Km and Vmax for xylan were found to be 12.75 mg/ml and 165 micromol/mg/min. In the presence of metal ions such as Ca2+, Co2+, Mn2+, Ba2+, Mg2+ and protein disulphide reducing agents such as beta-mercaptoethanol and dithiotheritol (DTT) the activity of enzyme increased, where as strong inhibition of enzyme activity was observed in the presence of Cu2+, Ag+, Fe2+ and SDS. The crude enzyme hydrolysed lignocellulosic substrate, wheat bran as well as industrial pulp. PMID:18374565

Mohana, Sarayu; Shah, Amita; Divecha, Jyoti; Madamwar, Datta

2008-11-01

71

Lignosulfonate and elevated pH can enhance enzymatic saccharification of lignocelluloses  

Directory of Open Access Journals (Sweden)

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.

Wang ZJ

2013-01-01

72

Production of bioethanol : Structural characterization of pretreated lignocellulose  

DEFF Research Database (Denmark)

Efficient conversion of lignocellulosic materials to ethanol requires pretreatment and hydrolysis prior to the ethanolic fermentation. This pretreatment renders the biomass more susceptible to the subsequent hydrolysis. Of the wide variety of pretreatment methods presently available, wet oxidation (Bjerre et al., 1996; McGinnis et al., 1983; Schmidt & thomsen, 1997) and steam explosion (puls et al., 1985; Saddler et al., 1993) are among the most promising. However, fermentation of the pretreated hydrolysates with the anaerobic thermophilic bacterium Thermoanaerobacter mathranii strain A3M1, adapted to the hemicellulose hydrolysate, has until now resulted in low ethanol yields, indicating incomplete hydrolyzation or the presence of inhibitory compounds in the hydrolyzate (Ahring et al., 1996; Sommer, 1998). Therefore, a structural study of the hemicellulosefraction is being conducted. This includes investigations of the structure of the hemicellulose fraction prior to pretreatment, prior to hydrolysis, prior to fermentation, and after fermentation. Various techniques, such as gas chromatography / mass spectrometry (GC/MS), size-exclusion chromatography (SEC), and nuclear magnetic resonance spectrometry (NMR), will be used in this study. Preliminary results from these investigations will be presented and discussed.

Tranekjær, Michael; Sommer, Peter

1998-01-01

73

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

Science.gov (United States)

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

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

2014-06-01

74

Pretreatment of lignocellulosic wastes to improve ethanol and biogas production: a review.  

Science.gov (United States)

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 CO(2) and its explosion, alkaline hydrolysis, liquid hot-water pretreatment, organosolv processes, wet oxidation, ozonolysis, dilute-and concentrated-acid hydrolyses, and biological pretreatments. PMID:19325822

Taherzadeh, Mohammad J; Karimi, Keikhosro

2008-09-01

75

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

Science.gov (United States)

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. PMID:19325822

Taherzadeh, Mohammad J.; Karimi, Keikhosro

2008-01-01

76

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

Directory of Open Access Journals (Sweden)

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.

Keikhosro Karimi

2008-09-01

77

New process to degrade lignocellulose  

International Nuclear Information System (INIS)

Researchers at ARS' Southern Regional Research Center, New Orleans are developing a new process to degrade lignocellulose. The lignocellulosic material is treated with three parts (weight to volume) of a swelling agent such as sodium hydroxide, then subjected to gamma irradiation from cesium-137, a nuclear waste material, at dosage levels up to 50 Mrad. The resulting material is a dark, brownish liquid, containing a variety of sugars and small fragments of lignin degradation products. The sugar solution is sterile and ready to use for fermentation or other aseptic processes

78

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

Science.gov (United States)

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 ?-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

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

2014-12-01

79

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

Energy Technology Data Exchange (ETDEWEB)

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. 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 75C. Both microorganisms simultaneously and completely utilized all pentoses, hexoses and oligomeric saccharides up to a total concentration of 17 g l{sup -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 H{sub 2} 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{sup -1}, sugar consumption was incomplete, and lower hydrogen yields of 2.0 to 2.4 mol per mol of consumed hexose were obtained. 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.

De Vrije, G.J.; Bakker, R.R.; Budde, M.A.W.; Lai, M.H.; Mars, A.E.; Claassen, P.A.M. [Agrotechnology and Food Sciences Group, Wageningen University and Research Centre, PO Box 17, 6700 AA Wageningen (Netherlands)

2009-06-17

80

Oligomeric hydrolysable tannins from Tibouchina multiflora.  

Science.gov (United States)

Two hydrolysable tannins, nobotanin O and nobotanin P, were isolated from the leaf extract of Tibouchina multiflora (Melastomataceae) and their dimeric and tetrameric structures elucidated on the basis of spectral data and chemical correlations with nobotanin B and K, respectively. Thirteen known hydrolysable tannins including nobotanins A, B, C and J, which are oligomers characteristic of the Melastomataceae, were also isolated. PMID:10647222

Yoshida, T; Amakura, Y; Yokura, N; Ito, H; Isaza, J H; Ramirez, S; Pelaez, D P; Renner, S S

1999-12-01

 
 
 
 
81

Degradation of ligno-cellulose biomass  

Energy Technology Data Exchange (ETDEWEB)

The use of lignocellulose to produce chemicals like furfural, ethyl alcohol, crude and refined sugars, acetone, butanol, levulinic acid, oxalic acid, hydrocarbon fuel, lignocellulose plastics etc. require operations like hydrolysis, oxidation, fermentations, pyrolysis and reduction. As a matter of fact every known chemical could conceivably be made from wood. The crux of the situation is economics. Degradation of lignocellulose could be broadly effected by (I) Pyrolysis, (II) Hydrolysis, (III) Biodegradation, (IV) Radiolysis by gamma rays.

Chawla, J.S.

1985-10-01

82

ARE LIGNOCELLULOSIC RESOURCES TOO VALUABLE TO BURN?  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Lignocellulosic matter often can be counted as a renewable resource, since it is produced by photosynthesis. But there are limits to how much biomass our society can use in a sustainable manner. People can debate whether or not it makes sense to use a substantial portion of lignocellulosic materials as a source of liquid fuel. This essay gives a qualified affirmative answer to the question in its title. However, combustion of lignocellulosic resources can be considered as wasteful and une...

Hubbe, Martin A.

2008-01-01

83

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

Science.gov (United States)

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

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

2011-12-01

84

Actinopyga lecanora Hydrolysates as Natural Antibacterial Agents  

Directory of Open Access Journals (Sweden)

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.

Raheleh Ghanbari

2012-12-01

85

LIGNOCELLULOSE NANOCOMPOSITE CONTAINING COPPER SULFIDE  

Directory of Open Access Journals (Sweden)

Full Text Available Copper sulfide-containing lignocellulose nanocomposites with improved electroconductivity were obtained. Two methods for preparing the copper sulfide lignocellulose nanocomposites were developed. An optimization of the parameters for obtaining of the nanocomposites with respect to obtaining improved electroconductivity, economy, and lower quantities and concentration of copper and sulfur ions in waste waters was conducted. The mechanisms and schemes of delaying and subsequent connection of copper sulfides in the lignocellulosic matrix were investigated. The modification with a system of 2 components: cupric sulfate pentahydrate (CuSO4. 5H2O and sodium thiosulfate pentahydrate (Na2S2O3.5H2O for wood fibers is preferred. Optimal parameters were established for the process: 40 % of the reduction system; hydromodule M=1:6; and ratio of cupric sulfate pentahydrate:sodium thiosulfate pentahydrate = 1:2. The coordinative connection of copper ions with oxygen atoms of cellulose OH groups and aromatic nucleus in lignin macromolecule was observed.

Sanchi Nenkova

2011-04-01

86

Optimization study of ethanolic fermentation from oil palm trunk, rubberwood and mixed hardwood hydrolysates using Saccharomyces cerevisiae.  

Science.gov (United States)

Ethanolic fermentation using Saccharomyces cerevisiae was carried out on three types of hydrolysates produced from lignocelulosic biomass which are commonly found in Malaysia such as oil palm trunk, rubberwood and mixed hardwood. The effect of fermentation temperature and pH of hydrolysate was evaluated to optimize the fermentation efficiency which defined as maximum ethanol yield in minimum fermentation time. The fermentation process using different temperature of 25 degrees Celsius, 30 degrees Celsius and 40 degrees Celsius were performed on the prepared fermentation medium adjusted to pH 4, pH 6 and pH 7, respectively. Results showed that the fermentation time was significantly reduced with the increase of temperature but an adverse reduction in ethanol yield was observed using temperature of 40 degrees Celsius. As the pH of hydrolysate became more acidic, the ethanol yield increased. Optimum fermentation efficiency for ethanolic fermentation of lignocellulosic hydrolysates using S. cerevisiae can be obtained using 33.2 degrees Celsius and pH 5.3. PMID:20056407

Chin, K L; H'ng, P S; Wong, L J; Tey, B T; Paridah, M T

2010-05-01

87

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

Energy Technology Data Exchange (ETDEWEB)

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.)

Saari, P.

2011-06-15

88

Bio-production of a polyalcohol (xylitol) from lignocellulosic resources : a review  

Energy Technology Data Exchange (ETDEWEB)

Lignocellulosic materials that are supplied from several sources at a low price can be utilized as feedstock for chemicals and bio-products. Xylitol is a high value polyalcohol produced by the reduction of D-xylose. It has many advantageous properties, such as low-calorie sweetening power. Due to its higher yield and because downstream processing is expected to be less costly, biotechnological production of xylitol is often more attractive than the chemical method of catalytic hydrogenation. Studies about the bio-production of xylitol, have been mostly focused on establishing the operational parameters and the process options that maximize its yield and productivity in free cell systems. However, some gaps in knowledge exist regarding this bioconversion process in immobilized cell systems and choosing an appropriate carrier for biocatalysts in a fermentation medium. This paper reviewed the metabolism of xylose by microorganisms, variables and process parameters affecting bioconversion of xylose to xylitol in defined media and complex media of lignocellulosic hydrolysates using free and immobilized cell systems. It discussed the natural occurrence, chemical structure, and physical properties of xylitol. Methods of production were discussed, including solid-liquid extraction; chemical production of xylitol; microbial production of xylitol; production of xylitol by bacteria; production of xylitol by molds; and production of xylitol by yeasts. The paper also discussed the parameters of fermentation, including xylose concentration; carbon source; nitrogen source; inoculum age and concentration; aeration rate; and temperature and pH. The production of xylitol from hemicellulose hydrolysate was also discussed along with immobilized-cell fermentation and xylitol recovery from fermented hydrolysate. It was concluded that purification and recovery of xylitol are the primary challenges related to this process, and a successful fermentation using immobilized cell system could be effective in cost reduction. 69 refs., 2 tabs., 3 figs.

Soleimani, M.; Tabil, L.; Panigrahi, S. [Saskatchewan Univ., Saskatoon, SK (Canada). Dept. of Agricultural and Bioresource Engineering

2006-07-01

89

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

Energy Technology Data Exchange (ETDEWEB)

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.

Larsson, Simona

2000-07-01

90

Applications of Protein Hydrolysates in Biotechnology  

Science.gov (United States)

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.

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

91

Improving the bioconversion yield of carbohydrates and ethanol from lignocellulosic biomass  

Science.gov (United States)

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.

Ewanick, Shannon M.

92

Ethanol and butanol production by fermentation of enzymatically saccharified SO/sub 2/-prehydrolysed lignocellulosics  

Energy Technology Data Exchange (ETDEWEB)

The present paper reports the results of SO/sub 2/-catalysed prehydrolysis of lignocellulosics, namely pine, aspen, and corn stover, and their direct saccharification, without washing, by cellulolytic enzymes to produce a mixture of hemicellulose and cellulose sugars. Total sugar yield upon enzymatic hydrolysis of these prehydrolysed residues was over 65% of the weight of raw material, or above 86% of theoretical yields. Fermentation by a strain of Pichia stipitis adapted to wood hydrolysates by recycling, designated the R strain, resulted in efficient utilization of xylose, high ethanol yields, and good tolerance of inhibitors. Fermentation of hydrolysates containing both the hemicellulose and cellulose sugars by P. stipitis R gave yields of 372, 346, and 388 l ethanol tonne/sup -1/ from pine, aspen, and corn stover, respectively. Extractive fermentation of these hydrolysates to acetone-butanol-ethanol by Clostridium acetobutylicum P262 using dibutylphthalate as in situ extractant in a semicontinuous mode resulted in rapid fermentation, when using a high cell concentration and recycling the cells for each 24-h fermentation to the succeeding batch. By this means, 255 l of acetone-butanol solvents were obtained per tonne of aspen, 298 l per tonne of pine, and 283 l per tonne of corn stover.

Parekh, S.R.; Parekh, R.S.; Wayman, Morris

1988-11-01

93

Butyric acid from anaerobic fermentation of lignocellulosic biomass hydrolysates by Clostridium tyrobutyricum strain RPT-4213  

Science.gov (United States)

A newly isolated Clostridium sp. strain RPT-4213 was found to produce butyrate under anaerobic conditions. Fermentations using Lactobacilli MRS Broth produced 9.47 g L-1 butyric acid from glucose (0.48 g/g glucose). However, the strain was not capable of utilizing five carbon sugars. To assess the a...

94

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

Energy Technology Data Exchange (ETDEWEB)

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.

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

2008-05-15

95

In situ biodiesel production from fast-growing and high oil content Chlorella pyrenoidosa in rice straw hydrolysate.  

Science.gov (United States)

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 performed for biodiesel production. The optimized condition was 1?g algal powder, 6?mL n-hexane, and 4?mL methanol with 0.5?M sulfuric acid at the temperature of 90°C in 2-hour reaction time, under which over 99% methyl ester content and about 95% biodiesel yield were obtained. The results suggested that the method has great potential in the production of biofuels with lignocellulose as an alternative carbon source for microalgae cultivation. PMID:21318171

Li, Penglin; Miao, Xiaoling; Li, Rongxiu; Zhong, Jianjiang

2011-01-01

96

Fractionating Recalcitrant Lignocellulose at Modest Reaction Conditions  

Energy Technology Data Exchange (ETDEWEB)

Effectively releasing the locked polysaccharides from recalcitrant lignocellulose to fermentable sugars is among the greatest technical and economic barriers to the realization of lignocellulose biorefineries because leading lignocellulose pre-treatment technologies suffer from low sugar yields, and/or severe reaction conditions, and/or high cellulase use, narrow substrate applicability, and high capital investment, etc. A new lignocellulose pre-treatment featuring modest reaction conditions (50 C and atmospheric pressure) was demonstrated to fractionate lignocellulose to amorphous cellulose, hemicellulose, lignin, and acetic acid by using a non-volatile cellulose solvent (concentrated phosphoric acid), a highly volatile organic solvent (acetone), and water. The highest sugar yields after enzymatic hydrolysis were attributed to no sugar degradation during the fractionation and the highest enzymatic cellulose digestibility ({approx}97% in 24 h) during the hydrolysis step at the enzyme loading of 15 filter paper units of cellulase and 60 IU of beta-glucosidase per gram of glucan. Isolation of high-value lignocellulose components (lignin, acetic acid, and hemicellulose) would greatly increase potential revenues of a lignocellulose biorefinery.

Zhang, Y.-H. Percival [Virginia Polytechnic Institute and State University (Virginia Tech); Ding, Shi-You [National Energy Renewable Laboratory; Mielenz, Jonathan R [ORNL; Cui, Jing-Biao [Dartmouth College; Elander, Richard T. [Dartmouth College; Laser, Mark [Dartmouth College; Himmel, Michael [ORNL; McMillan, James R. [National Energy Renewable Laboratory; Lynd, L. [Dartmouth College

2007-01-01

97

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

International Nuclear Information System (INIS)

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)

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

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...

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

2012-01-01

99

State of the Art Manufacturing of Protein Hydrolysates  

Science.gov (United States)

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.

Pasupuleti, Vijai K.; Braun, Steven

100

Protein hydrolysate components attractive to tephritids  

International Nuclear Information System (INIS)

Volatiles from protein hydrolysates have for a long time been known to attract tephritids. Many volatiles from protein hydrolysates have previously been identified, but no highly attractive materials have been determined. There have been few studies on the very low boiling components, other than ammonia. Because protein hydrolysate is more attractive to tephritids at alkaline rather than at slightly acidic conditions, vapours from Nu-Lure insect bait (NLIB) at pH4.5 and pH8.5 were examined by gas chromatography/mass spectrometry (GC/MS). Compounds identified by GC/MS did not evoke very high responses, therefore attention was focused on ammonia. Because ammonia is a gas at ambient temperatures and at atmospheric pressure, a slow release system was devised. Ammonia was tested with walnut husk flies in California and was found to be primarily attractive to the female flies. (author). 10 refs, 4 figs

 
 
 
 
101

Evaluation of oat hull hemicellulosic hydrolysate fermentability employing Pichia stipitis  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Oat hull hemicellulosic hydrolysate obtained by diluted acid hydrolysis was employed as fermentation medium for Pichia stipitis cultivation. A comparison between the use of treated hydrolysate with 1% activated charcoal to reduce the toxic compounds generated during the hydrolysis process and untreated hydrolysate as a control was conducted. In the cultures using treated hydrolysate the total consumption of glucose, low xylose consumption and ethanol and glycerol formation were observed. The ...

Luciana Cristina Silveira Chaud; Débora Danielle Virgínio da Silva; Rafael Taino de Mattos; Maria das Graças de Almeida Felipe

2012-01-01

102

Continuous ethanol production from wheat straw hydrolysate by recombinant ethanologenic Escherichia coli strain FBR5  

Energy Technology Data Exchange (ETDEWEB)

Continuous production of ethanol from alkaline peroxide pretreated and enzymatically saccharified wheat straw hydrolysate by ethanologenic recombinant Escherichia coli strain FBR5 was investigated under various conditions at controlled pH 6.5 and 35 C. The strain FBR5 was chosen because of its ability to ferment both hexose and pentose sugars under semi-anaerobic conditions without using antibiotics. The average ethanol produced from the available sugars (21.9-47.8 g/L) ranged from 8.8 to 17.3 g/L (0.28-0.45 g/g available sugars, 0.31-0.48 g/g sugar consumed) with ethanol productivity of 0.27-0.78 gl{sup -1} h{sup -1} in a set of 14 continuous culture (CC) runs (16-105 days). During these CC runs, no loss of ethanol productivity was observed. This is the first report on the continuous production of ethanol by the recombinant bacterium from a lignocellulosic hydrolysate. (orig.)

Saha, Badal C.; Cotta, Michael A. [U.S. Department of Agriculture, Peoria, IL (United States). Agricultural Research Service

2011-04-15

103

Lipid fermentation of corncob residues hydrolysate by oleaginous yeast Trichosporon cutaneum.  

Science.gov (United States)

Corncob residues (CCR) are cellulose residues of corncob after xylan (hemicellulose) is extracted for production of xylitol. Here, an oleaginous yeast Trichosporon cutaneum ACCC 20271 was screened for lipid fermentation using CCR hydrolysate. The initial carbon-to-nitrogen molar ratio (C/N ratio) and the initial sugar concentration of the CCR hydrolysate were investigated in the lipid fermentation of T. cutaneum ACCC 20271. A C/N ratio gradient was generated by changing the corn steep liquor (CSL) addition and an optimal C/N ratio of 49.3 was obtained. The different initial sugar concentration was obtained by changing the cellulase amount and the lipid titer was enhanced by the increased sugar concentration. To our knowledge, this is the first report on using CCR as the feedstock for lipid fermentation. The lipid titer of 12.3g/L and dry cell weight (DCW) of 38.4 g/L were the highest values among the studies using lignocellulose for lipid production. PMID:24321292

Gao, Qiuqiang; Cui, Zhenyang; Zhang, Jian; Bao, Jie

2014-01-01

104

Lipid accumulation by pelletized culture of Mucor circinelloides on corn stover hydrolysate.  

Science.gov (United States)

Microbial oil accumulated by fungal cells is a potential feedstock for biodiesel production, and lignocellulosic materials can serve as the carbon source to support the fungal growth. The dilute acid pretreatment of corn stover can effectively break down its lignin structure, and this process generates a hydrolysate containing mostly xylose at very dilute concentration and numerous by-products that may significantly inhibit the cell growth. This study utilized corn stover hydrolysate as the culture media for the growth of Mucor circinelloides. The results showed that Mucor cells formed pellets during the cell growth, which facilitates the cell harvest from dilute solution. The results also showed that the inhibitory effect of furfural, 5-hydroxymethylfurfural (HMF), and acetic acid could be avoided if their concentration was low. In fact, all these by-products may be assimilated as carbon sources for the fungal growth. The results proved the feasibility to reuse the cultural broth water for acid pretreatment and then use for subsequent cell cultivation. The results will have a direct impact on the overall water usage of the process. PMID:25080382

Reis, Cristiano E R; Zhang, Jianguo; Hu, Bo

2014-09-01

105

Development of yeast cultures for efficient fermentation of pentoses in cellulose hydrolysates  

Energy Technology Data Exchange (ETDEWEB)

Research was conducted to find a suitable yeast strain which could be utilized for the economical production of ethanol from xylose present in the hydrolysates of wood and in industrial waste products such as spent sulfite liquor. A test of over 500 yeast cultures did not uncover any strains with enhanced xylose fermentation potential, so known xylose-fermenting strains of Pichia stipitis and Candida shehatae were subjected to further studies. To mutate these strains to achieve high tolerance for acetic acid (the main inhibitor of yeast growth in xylose fermentation), the simultaneous adaptation of the cultures to increasing media concentration of acetic acid was attempted. This process finally yielded yeast mutants which could grow in the presence of acetic acid concentrations higher than that found in acid hydrolysates of wood. Experiments were then designed to evaluate the ability of the mutants to produce ethanol from extracts of steam-exploded aspen and spent sulfite liquor. When pertinent, a comparison with the wild-type culture was also made. The P. stipitis mutant could grow and ferment xylose at pH 4.0 and 0.4% acetic acid concentration in defined media. This mutant can also grow and ferment xylose in medium containing 60 vol % of hardwood spent sulfite liquor. With improvements in liquor pretreatment and development of a suitable co-fermentation technique, this abundant waste product could be more economically and efficiently fermented using the discovered P. stipitis mutant. 18 refs., 56 figs., 1 tab.

Mohandas, D.; Whelan, D.; Panchal, C.

1993-06-01

106

Biochemical and functional characterisation of casein and whey protein hydrolysates.  

Digital Repository Infrastructure Vision for European Research (DRIVER)

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...

Ven, C.

2002-01-01

107

Lignocellulosic Biomass Conversion: Status and Prospects  

Science.gov (United States)

The Advanced Technology Environmental and Energy Center (ATEEC) provides this presentation on lignocellulosic biomass conversion from Christopher Scarlata and Amie Sluiter. U.S. energy consumption and supply are covered as well as an overview of lignocellulosic biomass and the outlook for biomass technology in the United States. Users must download this resource for viewing, which requires a free log-in. There is no cost to download the item.

Scarlata, C. (Christopher)

108

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

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...

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

2008-01-01

109

Developing symbiotic consortia for lignocellulosic biofuel production  

Energy Technology Data Exchange (ETDEWEB)

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.)

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

2012-02-15

110

Development of a phenotypic assay for characterisation of ethanologenic yeast strain sensitivity to inhibitors released from lignocellulosic feedstocks.  

Science.gov (United States)

Inhibitors released by the breakdown of plant cell walls prevent efficient conversion of sugar into ethanol. The aim of this study was to develop a fast and reliable inhibitor sensitivity assay for ethanologenic yeast strains. The assay comprised bespoke 96-well plates containing inhibitors in isolation or combination in a format that was compatible with the Phenotypic Microarray Omnilog reader (Biolog, hayward, CA, USA). A redox reporter within the assay permits analysis of inhibitor sensitivity in aerobic and/or anaerobic conditions. Results from the assay were verified using growth on spot plates and tolerance assays in which maintenance of viability was assessed. The assay allows for individual and synergistic effects of inhibitors to be determined. It was observed that the presence of both acetic and formic acid significantly inhibited the yeast strains assessed, although this impact could be partially mitigated by buffering to neutral pH. Scheffersomyces stipitis, Candida spp., and Pichia guilliermondii demonstrated increased sensitivity to short chain weak acids at concentrations typically present in lignocellulosic hydrolysates. S. cerevisiae exhibited robustness to short chain weak acids at these concentrations. However, S. stipitis, Candida spp., and P. guilliermondii displayed increased tolerance to HMF when compared to that observed for S. cerevisiae. The results demonstrate that the phenotypic microarray assay developed in the current study is a valuable tool that can be used to identify yeast strains with desirable resistance to inhibitory compounds found in lignocellulosic hydrolysates. PMID:24664516

Greetham, D; Wimalasena, T; Kerruish, D W M; Brindley, S; Ibbett, R N; Linforth, R L; Tucker, G; Phister, T G; Smart, K A

2014-06-01

111

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

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, brewery’s spent grain and Eucalyptus wood chips. The soluble hemicellu...

Moura, Patri?cia; Carvalheiro, Florbela; Esteves, M. P.; Gi?rio, Francisco M.

2008-01-01

112

Ethanol production from wet-exploded wheat straw hydrolysate by thermophilic anaerobic bacterium Thermoanaerobacter BG1L1 in a continuous immobilized reactor.  

Science.gov (United States)

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 70 degrees C. Undetoxified wheat straw hydrolysate was used (3-12% dry matter), corresponding to sugar mixtures of glucose and xylose ranging from 12 to 41 g/l. The organism, thermophilic anaerobic bacterium Thermoanaerobacter BG1L1, exhibited significant resistance to high levels of acetic acid (up to 10 g/l) 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. PMID:18425616

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

2008-03-01

113

Ethanol production from wet-exploded wheat straw hydrolysate by thermophilic anaerobic bacterium Thermoanaerobacter BG1L1 in a continuous immobilized reactor  

DEFF Research Database (Denmark)

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/l. The organism, thermophilic anaerobic bacterium Thermoanaerobacter BG1L1, exhibited significant resistance to high levels of acetic acid (up to 10 g/l) 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.

Georgieva, Tania I.; Mikkelsen, Marie Just

2008-01-01

114

Co-production of bioethanol, lactic acid, electricity and heat from lignocellulosic biomass  

Energy Technology Data Exchange (ETDEWEB)

Large-scale CO2 abatement is a very important issue in our society. Many options are open to reach this goal including the bioconversion of biomass into either energy carriers or bulk chemicals. In this respect, bioethanol and lactic acid are excellent candidates as liquid fuel and bulk chemical, respectively. As for the biomass to be used as feedstock, potential interference with human consumption should be avoided. Hence, lignocellulosic biomass is the preferred option for future large scale processes. Bioethanol can be applied directly or in the form of ETBE in blends with petrol; lactic acid is a renewable alternative for petrochemical solvents and for production of polylactic acid (PLA) to replace petrochemical packaging materials and other synthetic materials. The preparation of fermentable sugars from lignocellulose is a major challenge for both bioethanol and lactic acid production and requires integral optimization of the trajectory from feedstock through fermentation to product recovery. The above issues have been addressed in the Netherlands in a 4.5-year R and D project (2002-2006) by a consortium of industries and R and D institutes in the framework of the EET-program. The overall project objective was to develop and evaluate technologies for the use of lignocellulose as feedstock for bioethanol and lactic acid production. Wheat straw was selected as the model feedstock. Major R and D themes in the project were: Physical/chemical pretreatment for mobilization of (hemi)cellulose from the lignocellulose matrix. Both mild acid pressurized hot water and mild alkaline pretreatment were studied; Optimization of enzymatic cellulose hydrolysis with commercially available enzymes; Use of lignocellulose hydrolysates for ethanol and lactic acid fermentation including optimization of the fermentation process setup and process conditions; Combined Heat and Power (CHP) generation from fermentation residues including evaluation of the potential utilisation of ashes as secondary building material or fertilizer; System modelling and evaluation and integral plant design including economic evaluation; Ecologic evaluation in the form of a screening LCA; Specification and formulation of bioethanol in blends with petrol.

Reith, J.H.; De Bont, J.A.M. (eds.) [ECN Biomass, Coal and Environmental Research, Petten (Netherlands)

2007-09-15

115

Lignocellulosic Biomass Pretreatment Using AFEX  

Science.gov (United States)

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

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

116

Ethanol production with dilute acid hydrolysis using partially dried lignocellulosics  

Science.gov (United States)

A process of converting lignocellulosic biomass to ethanol, comprising hydrolyzing lignocellulosic materials by subjecting dried lignocellulosic material in a reactor to a catalyst comprised of a dilute solution of a strong acid and a metal salt to lower the activation energy (i.e., the temperature) of cellulose hydrolysis and ultimately obtain higher sugar yields.

Nguyen, Quang A. (Chesterfield, MO); Keller, Fred A. (Lakewood, CO); Tucker, Melvin P. (Lakewood, CO)

2003-12-09

117

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

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...

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

2002-01-01

118

Decolorization of hair dye by lignocellulosic waste materials from contaminated waters  

Digital Repository Infrastructure Vision for European Research (DRIVER)

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 minimu...

AbelEnriqueNavarro; KarlaAliciaOrtiz; MaríaRosarioSun Kou

2014-01-01

119

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

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english 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.

J. M., Marton; M. G. A., Felipe; J. B., Almeida e Silva; A., Pessoa Júnior.

2006-03-01

120

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

Directory of Open Access Journals (Sweden)

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.

J. M. Marton

2006-03-01

 
 
 
 
121

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

Energy Technology Data Exchange (ETDEWEB)

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 H{sub 3}PO{sub 4}. Next, the hydrolysate was treated under adsorption conditions employing CDA powdered activated charcoal (1%) for 30 min at 60 deg C, 100 rpm and pH 2.5. The optimized xylitol volumetric productivity (0.50 g/L h) corresponded to a D-xyloseto- xylitol conversion of 0.66 g/g. (author)

Marton, J.M.; Felipe, M.G.A.; Almeida e Silva, J.B. [School of Chemical Engineering at Lorena (FAENQUIL), SP (Brazil). Dept. of Biotechnology], Email: jmarcelo@cetesb.sp.gov.br; Pessoa Junior, A. [University of Sao Paulo (USP), SP (Brazil)

2006-01-15

122

Methane fermentation of selected lignocellulosic materials  

Energy Technology Data Exchange (ETDEWEB)

Seven lignocellulosic materials: corn stover, napier grass, wood grass, newspaper, white fir and wheat straw from two different crops; two pure cellulosics: Solka Floc BW200 and Whatman No. 5 filter paper; and glucose, propionic and acetic acids were subjected to long-term batch methane fermentation. Ninety per cent of the original COD was recovered as methane gas from the two pure cellulosics and glucose. For the lignocellulosics, depending on the material, variations from over 80% conversion efficiency to methane for corn stover to less than 10% for white fir were observed. Generally, herbaceous materials were degraded faster and more extensively than woody biomass. A first-order rate model described well the methane fermentation process for the lignocellulosics tested, but was a poor model for the soluble substrates. (author).

Xinggang Tong; Smith, L.H.; McCarty, P.L. (Stanford Univ., CA (USA). Dept. of Civil Engineering)

1990-01-01

123

Actinopyga lecanora Hydrolysates as Natural Antibacterial Agents  

Digital Repository Infrastructure Vision for European Research (DRIVER)

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 posi...

Raheleh Ghanbari; Afshin Ebrahimpour; Azizah Abdul-Hamid; Amin Ismail; Nazamid Saari

2012-01-01

124

Biofilm production by Zymomonas mobilis enhances ethanol production and tolerance to toxic inhibitors from rice bran hydrolysate.  

Science.gov (United States)

Microorganisms play a significant role in bioethanol production from lignocellulosic material. A challenging problem in bioconversion of rice bran is the presence of toxic inhibitors in lignocellulosic acid hydrolysate. Various strains of Zymomonas mobilis (ZM4, TISTR 405, 548, 550 and 551) grown under biofilm or planktonic modes were used in this study to examine their potential for bioconversion of rice bran hydrolysate and ethanol production efficiencies. Z. mobilis readily formed bacterial attachment on plastic surfaces, but not on glass surfaces. Additionally, the biofilms formed on plastic surfaces steadily increased over time, while those formed on glass were speculated to cycle through accumulation and detachment phases. Microscopic analysis revealed that Z. mobilis ZM4 rapidly developed homogeneous biofilm structures within 24 hours, while other Z. mobilis strains developed heterogeneous biofilm structures. ZM4 biofilms were thicker and seemed to be more stable than other Z. mobilis strains. The percentage of live cells in biofilms was greater than that for planktonic cells (54.32 ± 7.10% vs. 28.69 ± 3.03%), suggesting that biofilms serve as a protective niche for growth of bacteria in the presence of toxic inhibitors in the rice bran hydrolysate. The metabolic activity of ZM4 grown as a biofilm was also higher than the same strain grown planktonically, as measured by ethanol production from rice bran hydrolysate (13.40 ± 2.43 g/L vs. 0.432 ± 0.29 g/L, with percent theoretical ethanol yields of 72.47 ± 6.13% and 3.71 ± 5.24% respectively). Strain TISTR 551 was also quite metabolically active, with ethanol production by biofilm and planktonically grown cells of 8.956 ± 4.06 g/L and 0.0846 ± 0.064 g/L (percent theoretical yields were 48.37 ± 16.64% and 2.046 ± 1.58%, respectively). This study illustrates the potential for enhancing ethanol production by utilizing bacterial biofilms in the bioconversion of a readily available and normally unusable low value by-product of rice farming. PMID:24930397

Todhanakasem, Tatsaporn; Sangsutthiseree, Atit; Areerat, Kamonchanok; Young, Glenn M; Thanonkeo, Pornthap

2014-09-25

125

Evaluation of oat hull hemicellulosic hydrolysate fermentability employing Pichia stipitis  

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Full Text Available Oat hull hemicellulosic hydrolysate obtained by diluted acid hydrolysis was employed as fermentation medium for Pichia stipitis cultivation. A comparison between the use of treated hydrolysate with 1% activated charcoal to reduce the toxic compounds generated during the hydrolysis process and untreated hydrolysate as a control was conducted. In the cultures using treated hydrolysate the total consumption of glucose, low xylose consumption and ethanol and glycerol formation were observed. The medium formulated with untreated hydrolysate showed morphological cell modifications with consequently cell death, no ethanol formation and formation of glycerol as byproduct of fermentative process, probably as a response to stressful conditions to yeast due to presence of high concentration of toxic compounds. Thus, further studies are suggested in order to determine the best conditions for hydrolysis and detoxification of the hydrolysate to improve the fermentative performance of P. stipitis.

Luciana Cristina Silveira Chaud

2012-10-01

126

Evaluation of oat hull hemicellulosic hydrolysate fermentability employing Pichia stipitis  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english Oat hull hemicellulosic hydrolysate obtained by diluted acid hydrolysis was employed as fermentation medium for Pichia stipitis cultivation. A comparison between the use of treated hydrolysate with 1% activated charcoal to reduce the toxic compounds generated during the hydrolysis process and untrea [...] ted hydrolysate as a control was conducted. In the cultures using treated hydrolysate the total consumption of glucose, low xylose consumption and ethanol and glycerol formation were observed. The medium formulated with untreated hydrolysate showed morphological cell modifications with consequently cell death, no ethanol formation and formation of glycerol as byproduct of fermentative process, probably as a response to stressful conditions to yeast due to presence of high concentration of toxic compounds. Thus, further studies are suggested in order to determine the best conditions for hydrolysis and detoxification of the hydrolysate to improve the fermentative performance of P. stipitis.

Luciana Cristina Silveira, Chaud; Débora Danielle Virgínio da, Silva; Rafael Taino de, Mattos; Maria das Graças de Almeida, Felipe.

2012-10-01

127

GENETICALLY MODIFIED LIGNOCELLULOSIC BIOMASS FOR IMPROVEMENT OF ETHANOL PRODUCTION  

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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.

Qijun Wang

2010-02-01

128

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

Science.gov (United States)

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

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

2010-08-01

129

PROTEIN HYDROLYSATES IN SPORTS AND EXERCISE: A BRIEF REVIEW  

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Full Text Available Protein can be hydrolyzed, producing small chains of amino acids called peptides. Several studies have shown that protein hydrolysates containing mostly di- and tripeptides are absorbed more rapidly than free form amino acids and much more rapidly than intact proteins. In addition, there is recent evidence that protein hydrolysate ingestion has strong insulinotropic effect. Thus, recovery sports drinks containing protein hydrolysates may be of great value

Anssi H. Manninen

2004-06-01

130

PROTEIN HYDROLYSATES IN SPORTS AND EXERCISE: A BRIEF REVIEW  

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Protein can be hydrolyzed, producing small chains of amino acids called peptides. Several studies have shown that protein hydrolysates containing mostly di- and tripeptides are absorbed more rapidly than free form amino acids and much more rapidly than intact proteins. In addition, there is recent evidence that protein hydrolysate ingestion has strong insulinotropic effect. Thus, recovery sports drinks containing protein hydrolysates may be of great value

Manninen, Anssi H.

2004-01-01

131

Simultaneous saccharification and cofermentation of lignocellulosic residues from commercial furfural production and corn kernels using different nutrient media  

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Full Text Available Abstract Background As the supply of starch grain and sugar cane, currently the main feedstocks for bioethanol production, become limited, lignocelluloses will be sought as alternative materials for bioethanol production. Production of cellulosic ethanol is still cost-inefficient because of the low final ethanol concentration and the addition of nutrients. We report the use of simultaneous saccharification and cofermentation (SSCF of lignocellulosic residues from commercial furfural production (furfural residue, FR and corn kernels to compare different nutritional media. The final ethanol concentration, yield, number of live yeast cells, and yeast-cell death ratio were investigated to evaluate the effectiveness of integrating cellulosic and starch ethanol. Results Both the ethanol yield and number of live yeast cells increased with increasing corn-kernel concentration, whereas the yeast-cell death ratio decreased in SSCF of FR and corn kernels. An ethanol concentration of 73.1 g/L at 120 h, which corresponded to a 101.1% ethanol yield based on FR cellulose and corn starch, was obtained in SSCF of 7.5% FR and 14.5% corn kernels with mineral-salt medium. SSCF could simultaneously convert cellulose into ethanol from both corn kernels and FR, and SSCF ethanol yield was similar between the organic and mineral-salt media. Conclusions Starch ethanol promotes cellulosic ethanol by providing important nutrients for fermentative organisms, and in turn cellulosic ethanol promotes starch ethanol by providing cellulosic enzymes that convert the cellulosic polysaccharides in starch materials into additional ethanol. It is feasible to produce ethanol in SSCF of FR and corn kernels with mineral-salt medium. It would be cost-efficient to produce ethanol in SSCF of high concentrations of water-insoluble solids of lignocellulosic materials and corn kernels. Compared with prehydrolysis and fed-batch strategy using lignocellulosic materials, addition of starch hydrolysates to cellulosic ethanol production is a more suitable method to improve the final ethanol concentration.

Cristhian Carrasco

2011-07-01

132

Recent Developments in the Bioconversion of Lignocelluloses into Ethanol  

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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.

KOESNANDAR

2008-12-01

133

Production of poly(3-hydroxybutyrate-co-4-hydroxybutyrate) by Burkholderia sacchari using wheat straw hydrolysates and gamma-butyrolactone.  

Science.gov (United States)

Burkholderia sacchari DSM 17165 is able to grow and produce poly(3-hydroxybutyrate) both on hexoses and pentoses. In a previous study, wheat straw lignocellulosic hydrolysates (WSH) containing high C6 and C5 sugar concentrations were shown to be excellent carbon sources for P(3HB) production. Using a similar feeding strategy developed for P(3HB) production based on WSH, fed-batch cultures were developed aiming at the production of the copolymer P(3HB-co-4HB) (poly(3-hydroxybutyrate-co-4-hydroxybutyrate)) by B. sacchari. The ability of this strain to synthesize P(3HB-co-4HB) was first shown in shake flasks using gamma-butyrolactone (GBL) as precursor of the 4HB units. Fed-batch cultures using glucose as carbon source (control) and GBL were developed to achieve high copolymer productivities and 4HB incorporations. The attained P(3HB-co-4HB) productivity and 4HB molar% were 0.7g/(Lh) and 4.7molar%, respectively. The 4HB incorporation was improved to 6.3 and 11.8molar% by addition of 2g/L propionic and acetic acid, respectively. When WSH were used as carbon source under the same feeding conditions, the values achieved were 0.5g/(Lh) and 5.0molar%, respectively. Burkholderia sacchari, a strain able to produce biopolymers based on xylose-rich lignocellulosic hydrolysates, is for the first time reported to produce P(3HB-co-4HB) using gamma butyrolactone as precursor. PMID:24811901

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

2014-11-01

134

Catalytic fast pyrolysis of lignocellulosic biomass  

Energy Technology Data Exchange (ETDEWEB)

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 fuel—bio-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.

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

2014-11-21

135

Catalytic fast pyrolysis of lignocellulosic biomass.  

Science.gov (United States)

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 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 fuel-bio-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 value, high corrosiveness, high viscosity, and instability; they also greatly 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. PMID:24801125

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

2014-11-21

136

Antioxidant Activity of Protein Hydrolysates of Fish and Chicken Bones  

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Argentine croaker (Umbrina canosai) and chicken (Gallus domesticus) bones were hydrolyzed with different proteases (Flavourzyme, ?-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 a...

Centenaro, G. S.; Mellado, M. S.; Prentice-herna?ndez, C.

2011-01-01

137

Efficient production of (R,R)-2,3-butanediol from cellulosic hydrolysate using Paenibacillus polymyxa ICGEB2008.  

Science.gov (United States)

We report here the production of pure (R,R)-2,3-butanediol (2,3-BDO) isomer by the non-pathogenic Paenibacillus polymyxa ICGEB2008 using lignocellulosic hydrolysate as substrate. Experimental design based on Plackett-Burman resulted in identification of Mn and K as most crucial salt elements along with the yeast extract for 2,3-BDO production. Further experiments using Box-Behnken design indicated that both KCl and yeast extract together had major impact on 2,3-BDO production. Optimized medium resulted in 2,3-BDO production with 2.3-fold higher maximum volumetric productivity (2.01 g/L/h) and similar yield (0.33 g/g sugar) as compared to rich yeast extract-peptone-dextrose medium in the bioreactor studies. Considering that the balance substrate was channeled towards ethanol, carbon recovery was close to theoretical yield between the two solvents, i.e., 2,3-BDO and ethanol. Biomass hydrolysate and corn-steep liquor was used further to produce 2,3-BDO without impacting its yield. In addition, 2,3-BDO was also produced via simultaneous saccharification and fermentation, signifying robustness of the strain. PMID:25424694

Adlakha, Nidhi; Yazdani, Syed Shams

2015-01-01

138

Antioxidant Activity of Protein Hydrolysates of Fish and Chicken Bones  

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Full Text Available Argentine croaker (Umbrina canosai and chicken (Gallus domesticus bones were hydrolyzed with different proteases (Flavourzyme, ?-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.

G.S. Centenaro

2011-08-01

139

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

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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.

Maria Elisabeth Machado Pinto e Silva

2008-01-01

140

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

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english 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 b [...] y 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.

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.

 
 
 
 
141

GENETICALLY MODIFIED LIGNOCELLULOSIC BIOMASS FOR IMPROVEMENT OF ETHANOL PRODUCTION  

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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 i...

Qijun Wang; Shengdong Zhu

2010-01-01

142

Extrusion Pretreatment of Lignocellulosic Biomass: A Review  

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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 ha...

Jun Zheng; Lars Rehmann

2014-01-01

143

Lignocellulose as raw material in fermentation processes  

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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,...

Mussatto, Solange I.; Teixeira, J. A.

2010-01-01

144

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

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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.

Yao Ding

2012-11-01

145

Processes for converting lignocellulosics to reduced acid pyrolysis oil  

Energy Technology Data Exchange (ETDEWEB)

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.

Kocal, Joseph Anthony; Brandvold, Timothy A

2015-01-06

146

Efficient production of sophorolipids by Starmerella bombicola using a corncob hydrolysate medium.  

Science.gov (United States)

Sophorolipids (SLs) are amphiphilic compounds produced from a variety of saccharides and vegetable oils by the yeast Starmerella bombicola and related strains, and they have commercial uses as detergents. In the present study, SL production was investigated using a corncob hydrolysate (CCH) medium derived from lignocellulosic feedstocks as a source of hydrophilic carbon substrates. Excess sulfuric acid concentrations during pretreatment of the corncobs increased the furfural concentrations and turned the CCH dark brown. The optimal sulfuric acid concentration was 1% (w/v), and the treated CCH, containing 45 g/l glucose, allowed the production of 33.7 g/l of SLs following 4 days of cultivation. Additional autoclaving (121°C, 20 min) inhibited SL production and cell growth by 36% and 40%, respectively. Ammonium nitrate (0.1 g-N/l) restored SL production to the autoclaved CCH. Finally, a cost-effective SL production of 49.2 g/l, with a volumetric productivity of 12.3 g/l/day, was achieved using CCH medium during batch cultivation in a jar fermentor. PMID:25240400

Konishi, Masaaki; Yoshida, Yuka; Horiuchi, Jun-Ichi

2014-09-15

147

Storage Stability of Food Protein Hydrolysates-a Review.  

Science.gov (United States)

ABSTRACT In recent years, mainly due to the specific health benefits associated with 1) the discovery of bioactive peptides in protein hydrolysates, 2) the reduction of protein allergenicity by protein hydrolysis, and 3) the improved protein digestibility and absorption of protein hydrolysates, the utilization of protein hydrolysates in functional foods and beverages has significantly increased. Although the specific health benefits from different hydrolysates are somewhat proven, the delivery and/or stability of these benefits is debatable during distribution, storage and consumption. In this review, we discuss 1) the quality changes in different food protein hydrolysates during storage; 2) the resulting changes in the structure and texture of three food matrices, i.e., low moisture foods (LMF, a w < 0.6), intermediate moisture foods (IMF, 0.6 ? a w < 0.85), and high moisture foods (HMF, a w ? 0.85); and 3) the potential solutions to improve storage stability of food protein hydrolysates. Additionally, we note there is a great need for evaluation of biofunction availability of bioactive peptides in food protein hydrolysates during storage. PMID:24915379

Rao, Qinchun; Kamdar, Andre Klaassen; Labuza, Theodore P

2013-08-12

148

Hydrolysis and fractionation of lignocellulosic biomass  

Science.gov (United States)

A multi-function process is described for the hydrolysis and fractionation of lignocellulosic biomass to separate hemicellulosic sugars from other biomass components such as extractives and proteins; a portion of the solubilized lignin; cellulose; glucose derived from cellulose; and insoluble lignin from said biomass comprising one or more of the following: optionally, as function 1, introducing a dilute acid of pH 1.0-5.0 into a continual shrinking bed reactor containing a lignocellulosic biomass material at a temperature of about 94 to about 160.degree. C. for a period of about 10 to about 120 minutes at a volumetric flow rate of about 1 to about 5 reactor volumes to effect solubilization of extractives, lignin, and protein by keeping the solid to liquid ratio constant throughout the solubilization process; as function 2, introducing a dilute acid of pH 1.0-5.0, either as virgin acid or an acidic stream from another function, into a continual shrinking bed reactor containing either fresh biomass or the partially fractionated lignocellulosic biomass material from function 1 at a temperature of about 94-220.degree. C. for a period of about 10 to about 60 minutes at a volumetric flow rate of about 1 to about 5 reactor volumes to effect solubilization of hemicellulosic sugars, semisoluble sugars and other compounds, and amorphous glucans by keeping the solid to liquid ratio constant throughout the solubilization process; as function 3, optionally, introducing a dilute acid of pH 1.0-5.0 either as virgin acid or an acidic stream from another function, into a continual shrinking bed reactor containing the partially fractionated lignocellulosic biomass material from function 2 at a temperature of about 180-280.degree. C. for a period of about 10 to about 60 minutes at a volumetric flow rate of 1 to about 5 reactor volumes to effect solubilization of cellulosic sugars by keeping the solid to liquid ratio constant throughout the solubilization process; and as function 4, optionally, introducing a dilute acid of pH 1.0-5.0 either as virgin acid or an acidic stream from another function, into a continual shrinking bed reactor containing the partially fractionated lignocellulosic biomass material from function 3 at a temperature of about 180-280.degree. C. for a period of about 10 to about 60 minutes at a volumetric flow rate of about 1 to about 5 reactor volumes to effect solubilization of cellulosic sugars by keeping the solid to liquid ratio constant throughout the solubilization process.

Torget, Robert W. (Littleton, CO); Padukone, Nandan (Denver, CO); Hatzis, Christos (Denver, CO); Wyman, Charles E. (Lakewood, CO)

2000-01-01

149

Production of Ethanol from Cocoa Pod Hydrolysate  

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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.

Othman Abd Samah

2011-07-01

150

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

Energy Technology Data Exchange (ETDEWEB)

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.

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

2014-04-01

151

Correlations between biochemical characteristics and foam-forming and -stabilizing ability of whey and casein hydrolysates  

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Whey protein and casein were hydrolyzed with 11 commercially available enzymes. Foam properties of 44 samples were measured and were related to biochemical properties of the hydrolysates using statistical data analysis. All casein hydrolysates formed high initial foam levels, whereas whey hydrolysates differed in their foam-forming abilities. Regression analysis using the molecular weight distribution of whey hydrolysates as predictors showed that the hydrolysate fraction containing peptides ...

Ven, C.; Bont, D. B. A.; Voragen, A. G. J.

2002-01-01

152

Cellulose and lignocellulose degradation by thermophilic and thermotolerant fungi  

Energy Technology Data Exchange (ETDEWEB)

Twenty-one species of thermophilic and thermotolerant fungi were tested for the ability to degrade cellulose and lignocellulose. Thielavai thermophila is newly described as cellulolytic. Only Chrysosporium pruinosum and Sporotrichum pulverulentum were found to degrade lignocellulose extensively. In a number of cases the moisture content of the solid substrate influenced degradation by the species tested.

Rosenberg, S.L.

1978-01-01

153

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

Energy Technology Data Exchange (ETDEWEB)

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).

Mark A. Eiteman PHD; Elliot Altman Phd

2009-02-11

154

Efficacy of a Fish Protein Hydrolysate in Malnourished Children  

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Protein hydrolysates are good nutritional supplements as their bioactive ingredients can be easily absorbed and utilized for various metabolic activities. A fish protein hydrolysate (Amizate), prepared by a unique process of hydrolysis has the advantage of high di/tri peptide content (<10 kDa) along with essential and non essential amino acids, micronutrients and vitamins. The effect of Amizate on malnourished children (6–8 years, a total of 438) of Grade I and II (Gomez’s classificatio...

Nesse, Knut Olav; Nagalakshmi, A. P.; Marimuthu, P.; Singh, Mamta

2011-01-01

155

Aspergilli and lignocellulosics: enzymology and biotechnological applications.  

Science.gov (United States)

Aspergilli are versatile ascomycetes that are able to transform at a rapid rate a wide spectrum of lignin-related aromatic compounds. While it is clear that these fungi can degrade phenolic and polysaccharide components from lignocellulosic material, the status regarding degradation of high-molecular mass lignins is controversial. This review compiles data from the literature as well as that from the authors' laboratory with the aim of clarifying this point. The main body of evidence points towards the inability of aspergilli alone to degrade lignin free of low-molecular mass contaminants. Nevertheless, the ability of this genus to efficiently degrade hemicelluloses makes it an essential participant in the complex microbial system necessary for wood decay under natural conditions. Aspergilli are known to overproduce high levels of hemicellulolytic enzymes. Out of the large array of these enzymes that act in concert to degrade lignocellulosic material, only endoxylanases of aspergilli are described in so far as these are the main activities required for enzyme-aided bleaching. The biochemical features of the endoxylanases from Aspergillus niger are briefly described as these serve to illustrate how a complex family of isozymes is necessary to deal with the structural and chemical heterogeneity of xylans. Emphasis is placed on the biotechnological applications of lignocellulosic materials transformed by aspergilli. The key application areas are biopulping and biobleaching where a reduction in the use of environmentally harmful chemicals traditionally used in the pulp and paper industry is envisaged. Waste water treatment represents another vast application area where aspergilli have been shown to be effective not only in colour removal but also in the bioconversion of potentially noxious substances into useful bioproducts. PMID:8167035

Duarte, J C; Costa-Ferreira, M

1994-03-01

156

SOIL FUNGI: POTENTIAL MYCOREMEDIATORS OF LIGNOCELLULOSIC WASTE  

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Full Text Available The continual expansion of urbanization and industrial activity has led to the accumulation of a large quantity of lignocellulosic residues throughout the world. In particular, large quantities of paper and bagasse are largely produced in Visakhapatnam. In this work we present the study of the degradability of these substrates with fungi. Three cultures of soil fungi were screened for their ability to degrade cellulose. Aspergillus flavus degraded the most, as shown by the highest CO2 release. Further, Aspergillus flavus was tested with the standard fungus Phanerochaete chrysosporium for cellulose degradation, which showed nearly equivalent potential.

Y. Avasn Maruthi

2010-05-01

157

Engineering furfural tolerance in Escherichia coli improves the fermentation of lignocellulosic sugars into renewable chemicals  

Science.gov (United States)

Pretreatments such as dilute acid at elevated temperature are effective for the hydrolysis of pentose polymers in hemicellulose and also increase the access of enzymes to cellulose fibers. However, the fermentation of resulting syrups is hindered by minor reaction products such as furfural from pentose dehydration. To mitigate this problem, four genetic traits have been identified that increase furfural tolerance in ethanol-producing Escherichia coli LY180 (strain W derivative): increased expression of fucO, ucpA, or pntAB and deletion of yqhD. Plasmids and integrated strains were used to characterize epistatic interactions among traits and to identify the most effective combinations. Furfural resistance traits were subsequently integrated into the chromosome of LY180 to construct strain XW129 (LY180 ?yqhD ackA::PyadC?fucO-ucpA) for ethanol. This same combination of traits was also constructed in succinate biocatalysts (Escherichia coli strain C derivatives) and found to increase furfural tolerance. Strains engineered for resistance to furfural were also more resistant to the mixture of inhibitors in hemicellulose hydrolysates, confirming the importance of furfural as an inhibitory component. With resistant biocatalysts, product yields (ethanol and succinate) from hemicellulose syrups were equal to control fermentations in laboratory media without inhibitors. The combination of genetic traits identified for the production of ethanol (strain W derivative) and succinate (strain C derivative) may prove useful for other renewable chemicals from lignocellulosic sugars. PMID:23431191

Wang, Xuan; Yomano, Lorraine P.; Lee, James Y.; York, Sean W.; Zheng, Huabao; Mullinnix, Michael T.; Shanmugam, K. T.; Ingram, Lonnie O.

2013-01-01

158

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

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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.

Johan O. Westman

2012-09-01

159

Removal and upgrading of lignocellulosic fermentation inhibitors by in situ biocatalysis and liquid-liquid extraction.  

Science.gov (United States)

Hydroxycinnamic acids are known to inhibit microbial growth during fermentation of lignocellulosic biomass hydrolysates, and the ability to diminish hydroxycinnamic acid toxicity would allow for more effective biological conversion of biomass to fuels and other value-added products. In this work, we provide a proof-of-concept of an in situ approach to remove these fermentation inhibitors through constituent expression of a phenolic acid decarboxylase combined with liquid-liquid extraction of the vinyl phenol products. As a first step, we confirmed using simulated fermentation conditions in two model organisms, Escherichia coli and Saccharomyces cerevisiae, that the product 4-vinyl guaiacol is more inhibitory to growth than ferulic acid. Partition coefficients of ferulic acid, p-coumaric acid, 4-vinyl guaiacol, and 4-ethyl phenol were measured for long-chain primary alcohols and alkanes, and tetradecane was identified as a co-solvent that can preferentially extract vinyl phenols relative to the acid parent and additionally had no effect on microbial growth rates or ethanol yields. Finally, E. coli expressing an active phenolic acid decarboxylase retained near maximum anaerobic growth rates in the presence of ferulic acid if and only if tetradecane was added to the fermentation broth. This work confirms the feasibility of donating catabolic pathways into fermentative microorganisms in order to ameliorate the effects of hydroxycinnamic acids on growth rates, and suggests a general strategy of detoxification by simultaneous biological conversion and extraction. Biotechnol. Bioeng. 2015;112: 627-632. © 2014 Wiley Periodicals, Inc. PMID:25311910

Tomek, Kyle J; Saldarriaga, Carlos Rafael Castillo; Velasquez, Fernando Peregrino Cordoba; Liu, Tongjun; Hodge, David B; Whitehead, Timothy A

2015-03-01

160

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

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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...

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

2014-01-01

 
 
 
 
161

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

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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.

Fatoumata Tounkara

2013-06-01

162

Pork fat hydrolysed by Staphylococcus xylosus  

DEFF Research Database (Denmark)

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 of fatty acids. The free fatty acids were determined both qualitatively and quantitatively. The effects of incubtion temperature and pH were studied using Response Surface Methodology. Within the area of interest for the producion of fermented sausages, no local maximum or minimum liberation of fatty acids was found. A rise in pH increased the amount of free fatty acids. Below pH 5.0, the amount of liberated fatty acids was insignificant although the viable count was >10+6 cell/ g emulsion. Of the two factors, pH was most influential in affecting the amount of free fatty acids. A rise in temperaure only slightly increased the amount of free fatty acids and hydrolysis took place at all temperatures from 14°C to 27°C. The strain liberates the fatty acids in a nonspecific way, in about the same proportions as those in which they occur in the pork fat.

SØrensen, B. B.; Stahnke, Louise Heller

1993-01-01

163

Safety assessment of hydrogenated starch hydrolysates.  

Science.gov (United States)

Hydrogenated starch hydrolysates (HSH) are mixtures of polyhydric alcohols such as sorbitol, maltitol, and higher-order sugar alcohols. They are important food ingredients because of their sweetness, low cariogenic potential, and useful functional properties. These traits permit HSH products to be used as viscosity or bodying agents, humectants, crystallization modifiers, and rehydration aids. A substantial body of safety information is available for HSH products and their individual chemical components. Based on this information, the substances have received favorable evaluations from international expert safety organizations such as the Joint FAO/WHO Expert Committee on Food Additives (JECFA) and European Community's Scientific Committee for Food. This same information has been submitted to the United States Food and Drug Administration (FDA) as part of the petitioning process to affirm the generally recognized as safe (GRAS) status of these substances. Some of the animal feeding studies important to a full safety assessment for HSH substances, while long available to international safety expert organizations and governmental organizations, have never been published in the literature. Three of these studies, i.e., a chronic (24-month) feeding study, a multigeneration reproduction study, and a teratology study, are reported on this article, together with metabolic information. The results of this evaluation establish HSH substances as safe food ingredients. PMID:8234920

Modderman, J P

1993-08-01

164

Amylase binding to starch granules under hydrolysing and non-hydrolysing conditions.  

Science.gov (United States)

Although considerable information is available about amylolysis rate, extent and pattern of granular starches, the underlying mechanisms of enzyme action and interactions are not fully understood, partly due to the lack of direct visualisation of enzyme binding and subsequent hydrolysis of starch granules. In the present study, ?-amylase (AA) from porcine pancreas was labelled with either fluorescein isothiocyanate (FITC) or tetramethylrhodamine isothiocyanate (TRITC) fluorescent dye with maintenance of significant enzyme activity. The binding of FITC/TRITC-AA conjugate to the surface and interior of granules was studied under both non-hydrolysing (0 °C) and hydrolysing (37 °C) conditions with confocal microscopy. It was observed that enzyme binding to maize starch granules under both conditions was more homogenous compared with potato starch. Enzyme molecules appear to preferentially bind to the granules or part of granules that are more susceptible to enzymic degradation. The specificity is such that fresh enzyme added after a certain time of incubation binds at the same location as previously bound enzyme. By visualising the enzyme location during binding and hydrolysis, detailed information is provided regarding the heterogeneity of granular starch digestion. PMID:25256464

Dhital, Sushil; Warren, Frederick J; Zhang, Bin; Gidley, Michael J

2014-11-26

165

40 CFR 180.1246 - Yeast Extract Hydrolysate from Saccharomyces cerevisiae: exemption from the requirement of a...  

Science.gov (United States)

...Extract Hydrolysate from Saccharomyces cerevisiae: exemption from the requirement of...Extract Hydrolysate from Saccharomyces cerevisiae: exemption from the requirement of...Extract Hydrolysate from Saccharomyces cerevisiae on all food commodities when...

2010-07-01

166

Desalting Fish Skin Protein Hydrolysates Using Macroporous Adsorption Resin  

Directory of Open Access Journals (Sweden)

Full Text Available Macroporous Adsorption Resin (MAR DA 201-C was used to desalt different Fish Skin Protein Hydrolysates (FSPHs. The FSPHs were obtained by hydrolysis of fish skin using Alcalase in a batch reactor a 60°C and pH 8.25. The ash was removed by adsorbing FSPHs onto MAR. Desorption was achieved by washing with alcohol at different concentrations. Ash content of the FSPHs was reduced from 4.69-5.57 to 1.07-2.48% range. The protein content was enriched from 89.07-90.82 to 94.89-96.38% range. MAR has good hydrolysate recoveries. The use of MAR showed promising results in decolourization and fishy flavour reduction. Nile tilapia and Nile perch skin protein hydrolysates were moderately bitter compared to Grass carp skin protein hydrolysates. The bitter taste in FSPHs was reduced to slightly detectable levels by our sensor panel. The hydrolysates had relatively low molecular weight. The process of applying MAR to desalt and debitter FSPHs is feasible.

Joseph Wasswa

2007-01-01

167

Physiological Importance and Mechanisms of Protein Hydrolysate Absorption  

Science.gov (United States)

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.

Zhanghi, Brian M.; Matthews, James C.

168

Extrusion pretreatment of lignocellulosic biomass: a review.  

Science.gov (United States)

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. PMID:25334065

Zheng, Jun; Rehmann, Lars

2014-01-01

169

Extrusion Pretreatment of Lignocellulosic Biomass: A Review  

Directory of Open Access Journals (Sweden)

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.

Jun Zheng

2014-10-01

170

Emulsifying and emulsion-stabilizing properties of gluten hydrolysates.  

Science.gov (United States)

Gluten is produced as a coproduct of the wheat starch isolation process. In this study, gluten was hydrolyzed to degrees of hydrolysis (DH) of 3-6-10 and 1-2-3 with alcalase and trypsin, respectively. These peptidases have a clearly distinct substrate specificity. Corn oil-in-water emulsions (10 wt % oil) were prepared by high-pressure homogenization at pH 7.5. Gluten peptides with DH 3 proved to be the most effective in producing peptides displaying emulsifying properties. Higher levels of alcalase hydrolysates (2.0 wt %) than of trypsin hydrolysates (1.0 wt %) were required to produce stable emulsions with small droplet sizes, which is attributed to differences in the nature of the peptides formed. The emulsions had small mean droplet diameters (d32 gluten hydrolysates in food and beverage products. PMID:24571632

Joye, Iris J; McClements, David J

2014-03-26

171

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

Science.gov (United States)

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.

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

2014-09-01

172

Possible application of brewer’s spent grain in biotechnology  

Directory of Open Access Journals (Sweden)

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.

Pejin Jelena D.

2013-01-01

173

Multiple Levels of Synergistic Collaboration in Termite Lignocellulose Digestion  

Digital Repository Infrastructure Vision for European Research (DRIVER)

In addition to evolving eusocial lifestyles, two equally fascinating aspects of termite biology are their mutualistic relationships with gut symbionts and their use of lignocellulose as a primary nutrition source. Termites are also considered excellent model systems for studying the production of bioethanol and renewable bioenergy from 2nd generation (non-food) feedstocks. While the idea that gut symbionts are the sole contributors to termite lignocellulose digestion has remained popular and ...

Scharf, Michael E.

2011-01-01

174

The chemistry involved in the steam treatment of lignocellulosic materials  

Digital Repository Infrastructure Vision for European Research (DRIVER)

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 ...

Luiz Pereira Ramos

2003-01-01

175

ANAEROBIC DIGESTION OF LIGNOCELLULOSIC MATERIALS USED IN BIOGAS PRODUCTION  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This diploma work presents a study regarding the impact of the pre-treatment of lignocellulosic materials with fungus Trametes Versicolor fungus, and the presence of lignin at different ratios, on the resulting amount of biogas produced during the process of anaerobic digestion. In addition, the degree of lignin decomposition was studied after the process had finished. Furthermore, the time-dependence of the lignin content within those lignocellulosic materials treated with Trametes Versicolo...

Radojkovic?, Vuk

2013-01-01

176

Ligno-cellulose based materials : "Process forming and Characterization"  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This work aims at developing new ligno-cellulosic biomass based materials as a way for giving added value to this raw material. This study aimed at developing three different new ways of using ligno-cellulosic components to get a large overview of the possible technical materials. The first way deals with the preparation of natural fibres filled lignin fibreboard panels. Improvements in panels forming have been achieved by using either chemical treatment or novel compatibilisation to improve ...

Privas, Edwige

2013-01-01

177

Techno-economic analysis of lignocellulosic ethanol: A review  

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Lignocellulosic ethanol is expected to be commercialised during the next decade as renewable energy for transport. Competiveness with first generation bioethanol and with gasoline is commonly considered in techno-economic analyses for commercial stage. Several existing reviews conclude about the high spread of current and projected production costs of lignocellulosic ethanol due to the significant differences in assumptions concerning the following factors: composition and cost of feedstock, ...

Gnansounou, Edgard; Dauriat, Arnaud

2010-01-01

178

Optimisation of the angiotensin converting enzyme inhibition by whey protein hydrolysates using response surface methodology  

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Protein hydrolysates inhibiting the angiotensin converting enzyme (ACE) in vitro, are potentially interesting constituents for blood pressure decreasing products. To minimise the amount of hydrolysate needed, the ACE inhibitory activity should be maximised. The total peptide composition of a hydrolysate determines its ACE inhibitory ability and depends on the specificity of the proteolytic enzyme and the process conditions used for the production of the hydrolysate. In the present research, t...

Ven, C.; Gruppen, H.; Bont, D. B. A.; Voragen, A. G. J.

2002-01-01

179

Sensory analysis of hydrolysed meat preparations Análise sensorial de preparações com hidrolisados de carne  

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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, informatio...

Silva, Maria Elisabeth Machado Pinto E.; Maria Carolina von Atzingen

2010-01-01

180

FTIR spectra of whey and casein hydrolysates in relation to their functional properties  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Mid-infrared spectra of whey and casein hydrolysates were recorded using Fourier transform infrared (FTIR) spectroscopy. Multivariate data analysis techniques were used to investigate the capacity of FTIR spectra to classify hydrolysates and to study the ability of the spectra to predict bitterness, solubility, emulsifying, and foaming properties of hydrolysates. Principal component analysis revealed that hydrolysates prepared from different protein sources or with different classes of proteo...

Ven, C.; Muresan, S.; Gruppen, H.; Bont, D. B. A.; Merck, K. B.; Voragen, A. G. J.

2002-01-01

 
 
 
 
181

Factors affecting antioxidant activity of soybean meal and caseine protein hydrolysates  

International Nuclear Information System (INIS)

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

182

Cellulase-lignin interactions in the enzymatic hydrolysis of lignocellulose  

Energy Technology Data Exchange (ETDEWEB)

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.

Rahikainen, J.

2013-11-01

183

Evaluation of continuous ethanol fermentation of dilute-acid corn stover hydrolysate using thermophilic anaerobic bacterium Thermoanaerobacter BG1L1  

DEFF Research Database (Denmark)

Dilute sulfuric acid pretreated corn stover is potential feedstock of industrial interest for second generation fuel ethanol production. However, the toxicity of corn stover hydrolysate (PCS) has been a challenge for fermentation by recombinant xylose fermenting organisms. In this work, the thermophilic anaerobic bacterial strain Thermoanaerobacter BG1L1 was assessed for its ability to ferment undetoxified PCS hydrolysate in a continuous immobilized reactor system at 70°C. The tested strain showed significant resistance to PCS, and substrate concentrations up to 15% total solids (TS) were fermented yielding ethanol of 0.39–0.42 g/g-sugars consumed. Xylose was nearly completely utilized (89–98%) for PCS up to 10% TS, whereas at 15% TS, xylose conversion was lowered to 67%. The reactor was operated continuously for 135 days, and no contamination was seen without the use of any agent for preventing bacterial infections. This study demonstrated that the use of immobilized thermophilic anaerobic bacteria for continuous ethanol fermentation could be promising in a commercial ethanol process in terms of system stability to process hardiness and reactor contamination. The tested microorganism has considerable potential to be a novel candidate for lignocellulose bioconversion into ethanol.

Georgieva, Tania I.; Ahring, Birgitte Kiær

2007-01-01

184

Candida utilis assimilates oligomeric sugars in rice straw hydrolysate via the Calcium-Capturing-by-Carbonation (CaCCO) process for glutathione- and cell-biomass production.  

Science.gov (United States)

Rice-straw hydrolysate (RSH) prepared via the CaCCO (Calcium Capturing by Carbonation) process contains not only monosaccharides but also significant amounts of oligosaccharides. In this study, a glutathione-producing yeast, Candida utilis NBRC 0626, was found to assimilate those oligosaccharides. The yields of reduced glutathione (GSH) and dry cell weight (DCW) per consumed sugars in a medium with RSH after 72h incubation were 10.1mg/g-sugars and 0.49g/g-sugars, respectively. The yields were comparative to those in a medium containing a model monosaccharide mix, suggesting that the assimilated oligosaccharides contribute to additional GSH and DCW production. Glycosyl linkage analysis indicated that the yeast could cleave xylose-, galactose-, and arabinose residues as well as glucose residues at the non-reducing ends. After 72h incubation, 99.1% of the total glucose residues and 84.2% of the total xylose residues in RSH were depleted. Thus the yeast could be applied for efficient utilization of lignocellulosic hydrolysates. PMID:25241674

Koyama, Yoshiyuki; Zhao, Rui; Ike, Masakazu; Tokuyasu, Ken

2014-11-01

185

Oconee spent fuel rerack  

International Nuclear Information System (INIS)

Spent fuel storage problems facing electric utilities with nuclear generation are growing more critical as existing spent fuel storage capacity is utilized. Due to the inaccessibility of spent fuel reprocessing plants, alternative temporary solutions such as transfer of spent nuclear fuel to other storage facilities and increasing the capacity of existing storage facilities through reracking are becoming increasingly prevalent. This paper describes the method and installation of new racks for increasing the fuel storage capacity of unit 3 of Duke Power Company's Oconee Nuclear Station near Seneca, South Carolina

186

Evaluation of sorghum straw hemicellulosic hydrolysate for biotechnological production of xylitol by Candida guilliermondii  

Directory of Open Access Journals (Sweden)

Full Text Available A preliminary study on xylitol production by Candida guilliermondii in sorghum straw hemicellulosic hydrolysate was performed. Hydrolysate had high xylose content and inhibitors concentrations did not exceed the commonly found values in other hemicellulosic hydrolysates. The highest xylitol yield (0.44 g/g and productivity (0.19 g/Lh were verified after 72 hours.

L Sene

2011-09-01

187

Evaluation of sorghum straw hemicellulosic hydrolysate for biotechnological production of xylitol by Candida guilliermondii  

Digital Repository Infrastructure Vision for European Research (DRIVER)

A preliminary study on xylitol production by Candida guilliermondii in sorghum straw hemicellulosic hydrolysate was performed. Hydrolysate had high xylose content and inhibitors concentrations did not exceed the commonly found values in other hemicellulosic hydrolysates. The highest xylitol yield (0.44 g/g) and productivity (0.19 g/Lh) were verified after 72 hours.

Sene, L.; Arruda, P. V.; Oliveira, S. M. M.; Felipe, M. G. A.

2011-01-01

188

Mild alkali-pretreatment effectively extracts guaiacyl-rich lignin for high lignocellulose digestibility coupled with largely diminishing yeast fermentation inhibitors in Miscanthus.  

Science.gov (United States)

In this study, various alkali-pretreated lignocellulose enzymatic hydrolyses were evaluated by using three standard pairs of Miscanthus accessions that showed three distinct monolignol (G, S, H) compositions. Mfl26 samples with elevated G-levels exhibited significantly increased hexose yields of up to 1.61-fold compared to paired samples derived from enzymatic hydrolysis, whereas Msa29 samples with high H-levels displayed increased hexose yields of only up to 1.32-fold. In contrast, Mfl30 samples with elevated S-levels showed reduced hexose yields compared to the paired sample of 0.89-0.98 folds at pfermentation. Therefore, this study proposes an optimal approach for minor genetic lignin modification towards cost-effective biomass process in Miscanthus. PMID:25079210

Li, Ming; Si, Shengli; Hao, Bo; Zha, Yi; Wan, Can; Hong, Shufen; Kang, Yongbo; Jia, Jun; Zhang, Jing; Li, Meng; Zhao, Chunqiao; Tu, Yuanyuan; Zhou, Shiguang; Peng, Liangcai

2014-10-01

189

Laccase Enzymology in Relation to Lignocellulose Processing  

DEFF Research Database (Denmark)

Several studies have indicated that cellulase action on cellulose fibers and their conversion to glucose is inhibited by lignin and lignin-derived phenolic substances, which are released during the pretreatment of lignocellulosic biomass. A prerequisite for optimization of the cellulose-to-glucose conversion is to either get rid of the inhibitory substances or to alter them in a way, so they no longer decrease the action of cellulases. The main focus in the present work was the investigation of the influence of the enzymes that are being expressed from the white-rot fungi when lignin was present in the cultivation broth, on the cellulase catalyzed hydrolysis of pretreated biomass, and to understand the mechanism of their action on phenolic substances. In this thesis, 44 fungi from the genus Alternaria, Fusarium, Memnoniella, Stemphylium, Ulocladium, Ganoderma, Trametes, and Polyporus were evaluated for their ability to grow on lignocellulosic material, such as sugarcane bagasse – a competitive substrate forgrain bioethanol. From this investigation, four white-rot fungi (Ganoderma lucidum, Trametes versicolor, Polyporus brumalis, and Polyporus ciliatus), were selected for the growth on lignin (lignin alkaline) and investigated for production of enzymes under such conditions (Paper I). G. lucidum was found to produce high amounts of laccase which corresponded to its exceptional growth on lignocellulosic substrate and lignin. This observation led to a hypothesis that this particular laccase might act in a synergistic way with cellulase preparations and yield in higher cellulose-to-glucose catalyzed hydrolysis. To test this hypothesis the laccase-rich crude extract from G. lucidum was added to the cellulase catalyzed hydrolysis of cellulose from the pretreated sugarcane bagasse (Paper I). A positive outcome of this reaction, a 17% increase in the total glucose yields during cellulase catalyzed hydrolysis of cellulose, led to amplification of laccase gene and its expression in Pichia pastoris (Paper II). This approach was directed into obtaining a monocomponent laccase enzyme and to prove that the higher yields of cellulose-to-glucose conversion are partly due to the presence of laccase, and are not caused by the other proteins, present in the laccase-rich crude protein extract. The addition of the laccase from G. lucidum, expressed in P. pastoris resulted in a total increase in the glucose yields by 20 and 33% depending on the cellulase cocktail preparation. This discovery is significant considering the fact that the cellulase cocktail preparations, namely Cellic®CTec1 and Cellic®CTec2, are improved in respect to phenolic-derived, and end-substrate inhibitors. Additionally, the molecular dynamics simulations (MD) of the obtained amino acid sequence of the laccase from G. lucidum highlighted a potential mechanism of laccase detoxification of the cellulase-pretreated-biomass-derived inhibitors (Paper II). The mechanism of laccase reaction on the phenolic substrates was further evaluated by the literature study of the reactions that take place in the catalytic pocket of this oxidoreductases and the structural alteration that can lead to a more robust, or completely inactive, laccase (Review paper).

Sitarz, Anna Katarzyna

2013-01-01

190

Sustainable Process Design of Lignocellulose based Biofuel  

DEFF Research Database (Denmark)

Worldwide energy demand has increased steadily as the world population has grown and more countries have become industrialized. The major energy sources of the world still depend on fossil fuels, which are also the main sources for carbon dioxide emission. As the fossil fuels always pass through a combustion processing step, carbondioxide and other important greenhouse gases are released. This is considered non-renewable and non-sustainable energy and may be one of the major causes of global warming and therefore, climate change concerns coupled with high oil prices. This isdriving efforts to increase 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, thosesugar 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, abundantly available, and are also non-food crops. In this respect, Cassava rhizome has several characteristics that make it a potential feedstock for fuel ethanol production. It has high content of cellulose and hemicelluloses . The objective of this paper is to present a study focused on the sustainable process design of bioethanol production from cassava rhizome using various computer aided tools through a systematic and effiicient work-flow, The study includes process simulation, sustainability analysis, economic evaluation and life cycle assessment (LCA) according to a well-defined workflow that guarantees the deermination of sustainable process options, if they exist. . The paper will highlight an improved alternative process design compared to a base case (published) design in terms of production cost, waste, energy usage and environmental impacts, criteria that are asociated with sustainable process design. The final process design includes 39 unit operations, has a capacity of 150,000 L/day and produces dry ethanol (approximately 13.0% of cassava rhizome is converted to ethanol)

Mangnimit, Saranya; Malakul, Pomthong

191

Selection of lactic acid bacteria able to ferment inulin hydrolysates  

Directory of Open Access Journals (Sweden)

Full Text Available 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 regarding lactic acid yields andproductivity. After 48 hours of chicory and Jerusalem artichhoke hydrolysates fermentation, from all the studied strains, Lb2 produced the highest lactic acid yield (0.97%. Lb2 produced after 48 hours of fermentation the lowest pH value of 3.45±0.01. Lb2 showed greater lactic acid productivity compared to the other studied lactic acid bacteria, the highest values, 0.13 g·L-1·h-1fromJerusalem artichoke hydrolysate and 0.11g·L-1·h-1 from chicory hydrolysate, being produced after 24 hours of fermentation.

Octavian BASTON

2012-12-01

192

Radiation hydrolysate of tuna cooking juice with enhanced antioxidant properties  

International Nuclear Information System (INIS)

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 ?M to 1930 ?M and IC50 on superoxide anion was decreased from 3.91 ?g/mL to 1.29 ?g/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.he hydrolysis of protein.

193

Use of hemicellulose hydrolysate for beta-glucosidase fermentation.  

Science.gov (United States)

Hydrolysis of cellulose by Trichoderma cellulases often results in a mixture of glucose, cellobiose, and low-mol-wt cellodextrins. Cellobiose is nonfermentable for most yeasts, and therefore it has to be hydrolyzed to glucose by beta-glucosidase prior to ethanol fermentation. In the present study, the beta-glucosidase production of one Penicillium and three Aspergillus strains, which were previously selected out of 24 strains, was investigated on steam pretreated willow. Both steam-pretreated willow and hemicellulose hydrolysate, released during steam explosion of willow, were used as carbon sources. Reference cultivation runs were performed using prehydrolyzed Solka Floc and glucose. The four strains were compared with Trichoderma reesei regarding sugar consumption and beta-glucosidase production. Aspergillus niger and Aspergillus phoenicis proved to be the best enzyme producers on hemicellulose hydrolysate. The maximum beta-glucosidase activity, 4.60 IU/mL, was obtained when A. phoenicis was cultivated on the mixture of hemicellulose hydrolysate and steam-pretreated willow. The maximum yield of enzyme activity, 502 IU/g total carbohydrate, was obtained when Aspergillus foetidus was cultivated on the hemicellulose hydrolysate. PMID:18575992

Réczey, K; Brumbauer, A; Bollók, M; Szengyel, Z; Zacchi, G

1998-01-01

194

Spent fuel transporting cask  

International Nuclear Information System (INIS)

Purpose: To lower the degree of exposure of workers to radiation during the transport of spent fuel and also to improve transport efficiency by increasing the spent fuel holding capacity of the container. Method: A deplated uranium metal is interposed as a gamma ray shielding body between the inner and outer tubes of the shell of the spent fuel transport cask for the purpose of lessening the degree of exposure of workers to radiation by utilizing the excellent gamma ray shielding performance of the depleted uranium metal. Furthermore, the wall thickness of the whole container can be made thinner than casks in conventional use. Therefore, the cask capacity for holding the spent fuel can be increased and the transport efficiency improved. In addition, a large volume of depleted uranium metal is produced in the process of manufacturing fuel to be used for atomic power generation and in the process of re-processing the spent fuel, and can be effectively utilized. (Takahashi, M.)

195

Production of Lupinus angustifolius protein hydrolysates with improved functional properties  

Directory of Open Access Journals (Sweden)

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.

Millán, Francisco

2005-06-01

196

Protein Hydrolysates as Hypoallergenic, Flavors and Palatants for Companion Animals  

Science.gov (United States)

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.

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

197

Effect of Protein Hydrolysates on Pancreatic Cancer Cells  

DEFF Research Database (Denmark)

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 consisting of 3 to 20 amino acids, can be released from proteins upon degradation by proteolytic enzymes, e.g. in the intestinal tract. The numerous described bioactivities include antihypertensive, anticancerous, antimicrobial, and immunomodulating effects. Here, we investigate the effect of fish protein 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 activities affecting cell proliferation and ability to modulate caspase activity in pancreatic cancer cells COLO357 and BxPC-3 in vitro. A number of the hydrolysates showed caspase promoting activity; in particular products containing muscle tissue, i.e. belly flap, were able to stimulate caspase activity. Selected hydrolysis products were further fractionated by ultrafiltration into molecular sizes above and below 5 kDa and their activity and dose-dependence was tested.

Ossum, Carlo G.; Andersen, Lisa Lystbæk

198

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

Science.gov (United States)

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 80.4±11.9 and 96.4±8.36?M, respectively. PMID:25624207

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

2015-06-01

199

Preprocessing Moist Lignocellulosic Biomass for Biorefinery Feedstocks  

Energy Technology Data Exchange (ETDEWEB)

Biomass preprocessing is one of the primary operations in the feedstock assembly system of a lignocellulosic biorefinery. Preprocessing is generally accomplished using industrial grinders to format biomass materials into a suitable biorefinery feedstock for conversion to ethanol and other bioproducts. Many factors affect machine efficiency and the physical characteristics of preprocessed biomass. For example, moisture content of the biomass as received from the point of production has a significant impact on overall system efficiency and can significantly affect the characteristics (particle size distribution, flowability, storability, etc.) of the size-reduced biomass. Many different grinder configurations are available on the market, each with advantages under specific conditions. Ultimately, the capacity and/or efficiency of the grinding process can be enhanced by selecting the grinder configuration that optimizes grinder performance based on moisture content and screen size. This paper discusses the relationships of biomass moisture with respect to preprocessing system performance and product physical characteristics and compares data obtained on corn stover, switchgrass, and wheat straw as model feedstocks during Vermeer HG 200 grinder testing. During the tests, grinder screen configuration and biomass moisture content were varied and tested to provide a better understanding of their relative impact on machine performance and the resulting feedstock physical characteristics and uniformity relative to each crop tested.

Neal Yancey; Christopher T. Wright; Craig Conner; J. Richard Hess

2009-06-01

200

Optimization of enzyme complexes for lignocellulose hydrolysis.  

Science.gov (United States)

The ability of a commercial Trichoderma reesei cellulase preparation (Celluclast 1.5L), to hydrolyze the cellulose and xylan components of pretreated corn stover (PCS) was significantly improved by supplementation with three types of crude commercial enzyme preparations nominally enriched in xylanase, pectinase, and beta-glucosidase activity. Although the well-documented relief of product inhibition by beta-glucosidase contributed to the observed improvement in cellulase performance, significant benefits could also be attributed to enzymes components that hydrolyze non-cellulosic polysaccharides. It is suggested that so-called "accessory" enzymes such as xylanase and pectinase stimulate cellulose hydrolysis by removing non-cellulosic polysaccharides that coat cellulose fibers. A high-throughput microassay, in combination with response surface methodology, enabled production of an optimally supplemented enzyme mixture. This mixture allowed for a approximately twofold reduction in the total protein required to reach glucan to glucose and xylan to xylose hydrolysis targets (99% and 88% conversion, respectively), thereby validating this approach towards enzyme improvement and process cost reduction for lignocellulose hydrolysis. PMID:17058283

Berlin, Alex; Maximenko, Vera; Gilkes, Neil; Saddler, Jack

2007-06-01

 
 
 
 
201

Hydrolysis of lignocelluloses by penicillium funiculosum cellulase  

Energy Technology Data Exchange (ETDEWEB)

Enzymatic hydrolysis of cellulose is a promising method for the conversion of waste cellulose to glucose. During the past few years, the development of this technology has proceeded rapidly, with significant advances made in enzyme production, pretreatment, and hydrolysis. A variety of fungi are reported to produce cellulases but among these Trichoderma reesei and its mutants are powerful producers of cellulases. However, the search for new and possibly better sources of cellulase is continued due to the low levels of beta-glucosidase of T. reesei. Penicillium funiculosum produces a complete cellulase having endo-beta-1,4-glucanase (15-20 U/mL), exo-beta-1,4-glucanase (1.5-2.0 U/mL), and high beta-glucosidase (8-10 U/mL). The saccharification of alkali-treated cotton and bagasse by P. funiculosum enzyme was 70 and 63%, respectively. It was possible to obtain glucose concentration as high as 30% using 50% bagasse. It is of interest that the percent saccharification of cellulosic substrates with the Penicillium enzyme is comparable to that of T. reesei cellulase when the same amount of filter paper activity is used, although the endo-glucanase activity of the latter is two to three times higher. This communication reports the studies on saccharification of lignocelluloses by P. funiculosum cellulase and certain studies on the kinetic aspects. (Refs. 15).

Mishra, C.; Rao, M.; Seeta, R.; Srinivasan, M.C.; Deshpande, V.

1984-04-01

202

Bacterial conversion of lignocellulose to ethanol  

Energy Technology Data Exchange (ETDEWEB)

Technologies for fuel ethanol production from lignocellulose are currently available. The challenge today is to assemble these technologies into a commercial demonstration plant. Bacteria such as Escherichia coli strain KO11 have been specifically engineered to produce ethanol at greater than 90% of theoretical yield (40 g ethanol/L in 48 h) from all sugar constituents in hemicellulose (pentoses and hexoses). Methods have been developed to produce fermentable hemicellulose syrups containing high concentrations of sugars. The effectiveness of strain KO11 has been demonstrated with hemicellulose syrups at the 150-liter scale and with laboratory sugars at the 10,000-liter scale. Additional organisms such as Klebsiella oxytoca strain P2 have been engineered for the simultaneous saccharification and fermentation of cellulose (SSF). Cellulase enzymes is one of the major costs associated with all SSF processes. The new organisms eliminate the need for added cellobiase and in some cases produce part of the endoglucanase. Strain P2 has been tested with bagasse, purified cellulose and mixed waste office paper. A simple method of enzyme recycling was tested using strain P2 with office paper as a substrate. Ethanol yields were prejected to be over 539 liters per metric ton. With onsite production, the estimated cost of cellulose for this process is 8.5 cents (U.S.) per liter.

Ingram, L.O. [Univ. of Florida, Gainesville, FL (United States)

1996-10-01

203

Bioethanol from lignocellulosics: Status and perspectives in Canada.  

Science.gov (United States)

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

Mabee, W E; Saddler, J N

2010-07-01

204

Spent fuel management strategies  

International Nuclear Information System (INIS)

Nuclear fuel cycle is divided into two sections; front end and back end of the fuel cycle. Front end of the fuel cycle, which covers all the activities of the fuel cycle before the fuel goes into the reactor has better developed and well-defined technologies. For storage of the spent fuel which are subjects of the back end of the fuel cycle, the waste management policies are not so well defined. There are three approaches that exist today for management of spent fuel. 1. For once through or open fuel cycles direct disposal of spent fuel in a deep geological repository, 2. For closed fuel cycles reprocessing of spent fuel and recycling of the recovered plutonium and uranium in new mixed oxide (MOX) fuels, 3. The spent fuel is placed in long term interim storage pending a decision as to its ultimate reprocessing or disposal. There are so large scale geological repositories for the final disposal of spent fuel in operation. Studies on suitable site selection, design, construction and licensing take about 30-40 years. Reprocessing, on the other hand, produces plutonium and is therefore under close inspection because of the Non Proliferation Treaty. Today more countries are delaying their final decision about the spent fuel management approach and using the long term interim storage approach

205

Spent nuclear fuel storage  

International Nuclear Information System (INIS)

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)

206

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

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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.

Wei Hui

2011-11-01

207

Expression of Trichoderma reesei ?-Mannanase in Tobacco Chloroplasts and Its Utilization in Lignocellulosic Woody Biomass Hydrolysis  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Lignocellulosic ethanol offers a promising alternative to conventional fossil fuels. One among the major limitations in the lignocellulosic biomass hydrolysis is unavailability of efficient and environmentally biomass degrading technologies. Plant-based production of these enzymes on large scale offers a cost-effective solution. Cellulases, hemicellulases including mannanases and other accessory enzymes are required for conversion of lignocellulosic biomass into fermentable sugars. ?-mannana...

Agrawal, Pankaj; Verma, Dheeraj; Daniell, Henry

2011-01-01

208

LIGNOCELLULOSIC BIOMASS: A POTENTIAL FEEDSTOCK TO REPLACE PETROLEUM  

Directory of Open Access Journals (Sweden)

Full Text Available Sustainability considerations for product and energy production in a future US economy can be met with lignocellulosic biomass. The age of petroleum as the key resource to meet the US economy requirements is rapidly dwindling, given the limited resources of petroleum, the growing global population, and concurrent detrimental effects on environmental safety. The use of natural and renewable feedstocks such as trees and switchgrass is becoming more attractive; indeed, lignocellulosic biomass is becoming a logical alternative to petroleum in light of looming oil shortages, increases in oil prices, and environmental sustainability considerations. This editorial aims at providing a broad overview of the consider-ations for replacing the US petroleum economy with one based on lignocellulosic biomass.

Lucian A. Lucia

2008-11-01

209

Altered lignin biosynthesis using biotechnology to improve lignocellulosic biofuel feedstocks.  

Science.gov (United States)

Lignocellulosic feedstocks can be converted to biofuels, which can conceivably replace a large fraction of fossil fuels currently used for transformation. However, lignin, a prominent constituent of secondary cell walls, is an impediment to the conversion of cell walls to fuel: the recalcitrance problem. Biomass pretreatment for removing lignin is the most expensive step in the production of lignocellulosic biofuels. Even though we have learned a great deal about the biosynthesis of lignin, we do not fully understand its role in plant biology, which is needed for the rational design of engineered cell walls for lignocellulosic feedstocks. This review will recapitulate our knowledge of lignin biosynthesis and discuss how lignin has been modified and the consequences for the host plant. PMID:25051990

Poovaiah, Charleson R; Nageswara-Rao, Madhugiri; Soneji, Jaya R; Baxter, Holly L; Stewart, Charles N

2014-12-01

210

PRETREATMENT TECHNOLOGIES IN BIOETHANOL PRODUCTION FROM LIGNOCELLULOSIC BIOMASS  

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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.

Vanja Januši?

2008-06-01

211

The spent fuel fate  

International Nuclear Information System (INIS)

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.)

212

Spent fuel workshop'2002  

International Nuclear Information System (INIS)

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 ? 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 ? 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.)

213

Spent fuel storage and isolation  

International Nuclear Information System (INIS)

The principal spent fuel activities conducted within the commercial waste and spent fuel within the Commercial Waste and Spent Fuel Packaging Program are: simulated near-surface (drywell) storage demonstrations at Hanford and the Nevada Test Site; surface (sealed storage cask) and drywell demonstrations at the Nevada Test Site; and spent fuel receiving and packaging facility conceptual design. These investigations are described

214

Integration of Lignocellulosic Biomass into Renewable Energy Generation Concepts  

Directory of Open Access Journals (Sweden)

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.

KUSCH Sigrid

2009-08-01

215

Spent fuel storage chamber  

International Nuclear Information System (INIS)

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.)

216

Cellulosic hydrolysate toxicity and tolerance mechanisms in Escherichia coli  

Digital Repository Infrastructure Vision for European Research (DRIVER)

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 m...

Mills, Tirzah Y.; Sandoval, Nicholas R.; Gill, Ryan T.

2009-01-01

217

Hydrolyses of calcium phosphates-allografts composite in physiological solutions.  

Science.gov (United States)

Hydrolysis of calcium phosphates cement- allografts composite in calf serum and that in saline were examined in comparison with those of the calcium phosphates cement in both the solutions. The calcium phosphates cement consists of alpha-tricalcium phosphate (alpha-TCP), tetracalcium phosphate (TetCP), dicalcium phosphate dihydrate (DCPD), and hydroxyapatite (HAP), which is clinically used as Biopex. In the hydrolyses of Biopex-allografts composite in both the solutions, the calcium phosphates cement was transformed into HAP. On the other hand, in the hydrolyses of Biopex, HAP was formed after 1 day and octacalcium phosphate (OCP) was gradually formed after 7 days. In the presence of allografts, plate-like crystals were deposited and in the absence of allografts, needle-like crystals were deposited in both the solutions. By the addition of allografts, the hydrolysis process of the calcium phosphates cement was significantly changed. PMID:16617417

Nomoto, Takuya; Haraguchi, Keiji; Yamaguchi, Shunro; Sugano, Nobuhiko; Nakayama, Hirokazu; Sekino, Tohru; Niihara, Koichi

2006-04-01

218

Characterization of hydrolysates derived from enzymatic hydrolysis of wheat gluten.  

Science.gov (United States)

The aim of this study is to investigate the characteristics of wheat gluten hydrolysates. Enzymatic hydrolysis was performed using a papain (food-grade enzyme) in the present study. The gluten proteins were hydrolyzed for 8 h. During enzymatic hydrolysis, average peptide chain length in the hydrolysate decreased rapidly. Increasing proteolysis resulted in the increase in the contents of the soluble forms of nitrogen. However, the content of peptide nitrogen increased within the 1st 6 h, and then began to decrease. The percentage of the released peptides with molecular weight (MW) of over 15 kD decreased with extending enzymatic hydrolysis, while those with MW below 5 kD increased significantly (P gluten complex showed different behavior after enzymatic hydrolysis. The monomeric protein (gliadin) and soluble glutenin were prone to enzymatic hydrolysis, while insoluble glutenin was resistance to enzymatic hydrolysis. PMID:17995823

Wang, Jin-Shui; Zhao, Mou-Ming; Zhao, Qiang-Zhong; Bao, Yang; Jiang, Yue-Ming

2007-03-01

219

Use of Protein Hydrolysates in Industrial Starter Culture Fermentations  

Science.gov (United States)

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.

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

220

Lignocellulose degradation and crude protein formation by three ligninolytic Streptomyces strains  

Energy Technology Data Exchange (ETDEWEB)

Streptomyces strains (11A, 21B and 31C) were grown on guinea grass lignocellulose and their ability to decompose lignocellulose was monitored. All three Streptomyces strains caused lignocellulose weight losses ranging from 27 to 34%. The three Streptomyces strains were also found to metabolize between 27 and 40% of the lignin component and 22-29% of the carbohydrate component of lignocellulose over the 12 week incubation period. Crude protein increases of degraded guinea grass lignocellulose were between 10.1 and 14.5% over the same period.

Njoku, C.C.; Antai, S.P.

1987-01-01

 
 
 
 
221

Analysis of hydroxypropyl starch hydrolysates by high performance liquid chromatography  

Energy Technology Data Exchange (ETDEWEB)

Acid hydrolysates of hydroxypropyl derivatives of wheat, maize, waxy maize and high amylose maize starches were separated using four HPLC procedures. An amine treated silica column gave best resolution of glucose and six nonglucose components. The proportions of these varied depending on the native starch and the acid used for hydrolysis. There was a linear relationship between molar substitution and ratio of nonglucose peak areas which varied between the native starches.

Wootton, M.; Kesavamoorthy, S.; Azemi, B.M.N.M.

1985-08-01

222

Effect of Protein Hydrolysates on Pancreatic Cancer Cells  

Digital Repository Infrastructure Vision for European Research (DRIVER)

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 parti...

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

2010-01-01

223

Selection of lactic acid bacteria able to ferment inulin hydrolysates  

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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...

Baston, Octavian; Constantin, Oana Emilia

2012-01-01

224

Safety evaluation of fish protein hydrolysate supplementation in malnourished children.  

Science.gov (United States)

Amizate® is a proprietary protein hydrolysate preparation derived from Atlantic salmon (Salmo salar) using endogenous hydrolytic enzymes; it contains mostly free amino acids and short peptides, as well as small amounts of micronutrients (i.e., vitamins and minerals). In this study, the safety of supplementation with fish protein hydrolysate (Amizate®) was examined in 438 malnourished children in a randomized, placebo-controlled, double-blind, and parallel study. The children were between the ages of six to eight and met the Gomez classification for mild or moderate malnutrition. They were randomized to receive one of three interventions for four months, including a chocolate drink (control), or Amizate® (3 or 6g/day) in a chocolate drink. Administration of Amizate® was well-tolerated, with no adverse events reported. Growth (i.e., body weight gain, changes in height, and body mass index) was not negatively impacted by administration of Amizate®, and routine biochemical analysis of blood and urine samples did not reveal any abnormalities that were attributable to the intervention. Findings from this study demonstrate that daily consumption of 3 or 6g of fish protein hydrolysate (Amizate®) was safe and suitable for supplementing the diets of malnourished children. PMID:24569051

Nesse, Knut Olav; Nagalakshmi, A P; Marimuthu, P; Singh, Mamta; Bhetariya, Preetida J; Ho, Manki; Simon, Ryan R

2014-06-01

225

Bioflavour production from orange peel hydrolysate using immobilized Saccharomyces cerevisiae.  

Science.gov (United States)

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

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

2013-11-01

226

The Use of Protein Hydrolysates for Weed Control  

Science.gov (United States)

Corn gluten meal, the protein fraction of corn (Zea mays L.) grain, is commercially used as a natural weed control agent and nitrogen source in horticultural crops and in the turf and ornamental markets. Corn gluten hydrolysate, a water soluble form of gluten meal, has also been proposed for the same purpose, although it could be sprayed on the soil rather than applied in the granular form. Five depeptides, glutaminyl-glutamine (Gln-Gln), glycinyl-alanine (Gly-Ala), alanyl-­glutamine (Ala-Glu), alanyl-asparagine (Ala-Asp), and alaninyl-alanine (Ala-Ala) and a pentapeptide leucine-serine-proline-alanine-glutamine (Leu-Ser-Pro-Ala-Gln) were identified as the active components of the hydrolysate. Microscopic analysis revealed that Ala-Ala acted on some metabolic process rather than directly on the mitotic apparatus. Similar to the chloracetamides and sulfonyl-urea hebicides, Ala-Ala inhibits cell division rather than disrupting of cell division processes. Cellular ultrastructure changes caused by exposure to Ala-Ala implicate Ala-Ala as having membrane-disrupting characteristics similar to several synthetic herbicides. The potential use of the hydrolysate and the peptides as weed controls is discussed.

Christians, Nick; Liu, Dianna; Unruh, Jay Bryan

227

Radiation hydrolysate of tuna cooking juice with enhanced antioxidant properties  

Science.gov (United States)

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 ?M to 1930 ?M and IC50 on superoxide anion was decreased from 3.91 ?g/mL to 1.29 ?g/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.

Choi, Jong-il; Sung, Nak-Yun; Lee, Ju-Woon

2012-08-01

228

Rendered-protein hydrolysates for microbial synthesis of cyanophycin biopolymer.  

Science.gov (United States)

Cyanophycin is a poly(arginyl-aspartate) biopolymer produced and stored intracellularly by bacteria. Cyanophycin has been proposed as a renewable replacement for petrochemical-based industrial products. An abundant source of amino acids and nitrogen such as in the form of protein hydrolysates is needed for the biosynthesis of cyanophycin. Rendered proteins are largely used as a feed supplement in animal husbandry and aquaculture. New uses would expand the market size of this class of protein coproducts. We prepared and thoroughly characterized the hydrolysates of meat and bone meal, and proceeded to demonstrate for the first time that these hydrolysates could be used in the fermentative production of cyanophycin. Using the enzyme-hydrolyzed meat and bone meal preparation, we obtained crude cyanophycin product at 33-35% level of that produced using the reference casamino acids in both shake-flask and 10-L bioreactor fermentation studies. Polyacrylamide-gel electrophoresis of the cyanophycin under denaturing conditions showed the molecular weight of the isolated polyamide at 24kDa. Our results open a new avenue for the utilization of rendered protein coproducts to produce the cyanophycin biopolymer. PMID:21501699

Solaiman, Daniel K Y; Garcia, Rafael A; Ashby, Richard D; Piazza, George J; Steinbüchel, Alexander

2011-10-01

229

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

Energy Technology Data Exchange (ETDEWEB)

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)

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

230

Removal and recovery of molybdenum from aqueous solutions by adsorption onto Surfactant-Modified coir pith, a lignocellulosic polymer  

Energy Technology Data Exchange (ETDEWEB)

Coconut coir pith, a lignocellulosic polymer, is an unwanted by-product of the coir fiber industry. The pith was used as a biosorbent for the removal of Molybdenum(VI) after modification with a cationic surfactant, hexadecyltrimethylammonium bromide. The optimum pH for maximum adsorption of Mo(VI) was found to be 3.0. Langmuir, Freundlich and Dubinin Radushkevich isotherms were used to model the adsorption equilibrium data and the system was seen to follow all three isotherms. The Langmuir adsorption capacity of the biosorbent was found to be 57.5 mg g{sup -1}. Kinetic studies showed that the adsorption generally obeyed a second-order kinetic model. Desorption studies showed that the recovery of Mo(VI) from the spent adsorbent was feasible. The effect of foreign anions on the adsorption of Mo(VI) was also examined. (Abstract Copyright [2009], Wiley Periodicals, Inc.)

Namasivayam, Chinnaiya [Environmental Chemistry Division, Department of Environmental Sciences, Bharathiar University, Coimbatore (India); Sureshkumar, Molagoundanpalayam Venkatachalam [Department of Chemistry, PARK College of Engineering and Technology, Coimbatore (India)

2009-01-15

231

Purification and identification of antioxidant peptides from walnut (Juglans regia L.) protein hydrolysates.  

Science.gov (United States)

Walnut proteins were hydrolyzed separately using three different proteases to obtain antioxidant peptides. The antioxidant activities of the hydrolysates were measured using 1,1-diphenyl-2-picryl hydrazyl (DPPH) assay. Among hydrolysates, pepsin hydrolysate obtained by 3h exhibited the highest antioxidant activities, which could also quench the hydroxyl radical, chelate ferrous ion, exhibit reducing power and inhibit the lipid peroxidation. Then, 3-h pepsin hydrolysates were purified sequentially by ultrafiltration, gel filtration and RP-HPLC. The sequence of the peptide with the highest antioxidative activity was identified to be Ala-Asp-Ala-Phe (423.23 Da) using RP-HPLC-ESI-MS, which was identified for the first time from walnut protein hydrolysates. Last, the inhibition of the peptide on lipid peroxidation was similar with that of reduced glutathione (GSH). These results indicate that the protein hydrolysates and/or its isolated peptides may be effectively used as food additives. PMID:23022588

Chen, Ning; Yang, Hongmei; Sun, Yi; Niu, Jun; Liu, Shuying

2012-12-01

232

A rapid microassay to evaluate enzymatic hydrolysis of lignocellulosic substrates.  

Science.gov (United States)

Current attempts to produce ethanol from lignocellulosic biomass are focused on the optimization of pretreatment to reduce substrate recalcitrance and the improvement of enzymes for hydrolysis of the cellulose and hemicellulose components to produce fermentable sugars. Research aimed at optimizing both aspects of the bioconversion process involves assessment of the effects of multiple variables on enzyme efficiency, resulting in large factorial experiments with intensive assay requirements. A rapid assay for lignocellulose hydrolysis has been developed to address this need. Pretreated lignocellulose is formed into handsheets, which are then used to prepare small disks that are easily dispensed into microtiter plates. The hydrolysis of cellulose to glucose is estimated using an enzyme-coupled spectrophotometric assay. Using disks prepared from ethanol organosolv pretreated yellow poplar, it is shown that the assay generates data comparable with those produced by hydrolysis of pretreated yellow poplar pulp in Erlenmeyer flasks, followed by HPLC analysis of glucose. The assay shows considerable time and cost benefits over the standard assay protocol and is applicable to a broad range of lignocellulosic substrates. PMID:16345088

Berlin, Alex; Maximenko, Vera; Bura, Renata; Kang, Kyu-Young; Gilkes, Neil; Saddler, Jack

2006-04-01

233

Conversion of Lignocellulosic Biomass to Nanocellulose: Structure and Chemical Process  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Lignocellulosic biomass is a complex biopolymer that is primary composed of cellulose, hemicellulose, and lignin. The presence of cellulose in biomass is able to depolymerise into nanodimension biomaterial, with exceptional mechanical properties for biocomposites, pharmaceutical carriers, and electronic substrate's application. However, the entangled biomass ultrastructure consists of inherent properties, such as strong lignin layers, low cellulose accessibility to chemicals, and high cellulo...

Lee, H. V.; Hamid, S. B. A.; Zain, S. K.

2014-01-01

234

Conversion of lignocellulosic biomass to nanocellulose: structure and chemical process.  

Science.gov (United States)

Lignocellulosic biomass is a complex biopolymer that is primary composed of cellulose, hemicellulose, and lignin. The presence of cellulose in biomass is able to depolymerise into nanodimension biomaterial, with exceptional mechanical properties for biocomposites, pharmaceutical carriers, and electronic substrate's application. However, the entangled biomass ultrastructure consists of inherent properties, such as strong lignin layers, low cellulose accessibility to chemicals, and high cellulose crystallinity, which inhibit the digestibility of the biomass for cellulose extraction. This situation offers both challenges and promises for the biomass biorefinery development to utilize the cellulose from lignocellulosic biomass. Thus, multistep biorefinery processes are necessary to ensure the deconstruction of noncellulosic content in lignocellulosic biomass, while maintaining cellulose product for further hydrolysis into nanocellulose material. In this review, we discuss the molecular structure basis for biomass recalcitrance, reengineering process of lignocellulosic biomass into nanocellulose via chemical, and novel catalytic approaches. Furthermore, review on catalyst design to overcome key barriers regarding the natural resistance of biomass will be presented herein. PMID:25247208

Lee, H V; Hamid, S B A; Zain, S K

2014-01-01

235

The IBUS process - lignocellulosic bioethanol close to a commercial reality  

Energy Technology Data Exchange (ETDEWEB)

Integrated Biomass Utilization System (IBUS) is a new process for converting lignocellulosic waste biomass to bioethanol. Inbicon A/S has developed the IBUS process in a large-scale process development unit. This plant features new continuous and energy-efficient technology developed for pretreatment and liquefaction of lignocellulosic biomass and has now been operated and optimized for four years with promising results. In the IBUS process, biomass is converted using steam and enzymes only. The process is energy efficient due to very high dry matter content in all process steps and by integration with a power plant. Cellulose is converted to bioethanol and lignin to a high-quality solid biofuel which supply the process energy as well as a surplus of heat and power. Hemicellulose is used as feed molasses but in the future it could also be used for additional ethanol production or other valuable products. Feasibility studies of the IBUS process show that the production price for lignocellulosic bioethanol is close to the world market price for fuel ethanol. There is still room for optimization - and lignocellulosic bioethanol is most likely a commercial alternative to fossil transport fuels before 2012. (Abstract Copyright [2008], Wiley Periodicals, Inc.)

Larsen, J.; Oestergaard Petersen, M.; Thirup, L.; Wen Li, H.; Krogh Iversen, F. [Inbicon A/S, Fredericia (Denmark)

2008-05-15

236

Lignin Production by Organosolv Fractionation of Lignocellulosic Biomass  

Energy Technology Data Exchange (ETDEWEB)

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.

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

2010-09-15

237

Membrane separations in ionic liquid assisted processing of lignocellulosic biomass  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Biokraftstoffe der 2. Generation haben heutzutage einen signifikanten Marktanteil erreicht. Aus diesem Erfolg resultiert die Verantwortung, Biokraftstoffe möglichst CO2 neutral, mit geringem Einfluss auf die Nahrungsmittelkette und durch eine vollständige Verwertung der Rohbiomasse herzustellen. Im Exzellenz-Cluster der RWTH Aachen ?Tailor-Made-Fuels from Biomass? wird deshalb die verfahrenstechnische Umsetzung von lignocellulose-haltiger Biomasse zu Biokraftstoffen und wirtschaftlich rel...

Abels, Christian

2013-01-01

238

Optimization of the enzyme system for hydrolysis of pretreated lignocellulose substrates; Optimering av enzymsystemet foer hydrolys av foerbehandlade lignocellulosa substrat  

Energy Technology Data Exchange (ETDEWEB)

This project aims to clarify the reasons for the slow and incomplete enzymatic hydrolysis of certain lignocellulose substrates, particularly softwood e.g. spruce. Based on this knowledge we will optimize the enzyme system so that the yield of fermentable sugars is increased as well as the rate of hydrolysis. We will also study methods for recycling of the enzymes in the process by adsorption on fresh substrate. Progress in these areas will lead to improved process economy in an ethanol process. We collaborate with Chemical Engineering on hydrolysis of pretreated lignocellulose substrates and with Analytical Chemistry and Applied Microbiology on analysis of potential inhibitors. Within this main research direction the work at Biochemistry during this project period (since 970701) has been focused on the following areas: (1) Studies of the role of substrate properties in the enzymatic hydrolysis to clarify the reasons for the decrease in the rate of hydrolysis; (2) enzyme adsorption on lignin; (3) studies of recently identified low molecular weight endo glucanases which may be used for more effective penetration of small pores in pretreated substrates (this part is financed by the Nordic Energy Research Program). Central results during the period: In order to study the role of substrate properties for hydrolysis we have initiated investigations on steam pretreated substrates with several techniques. Measurements of pore sizes have been done with probe molecules of known molecular weights. Results show that probe molecules with diameters larger than 50 Aangstroem can more easily penetrate pretreated willow compared with spruce, which can be a part of the explanation for the better hydrolysability of hardwood substrates compared with softwood. We have started studies with electron microscopy of pretreated substrates at different degrees of enzymatic hydrolysis. With scanning electron microscopy (SEM) we can see significant differences in substrate structure in comparisons before and after hydrolysis. For better interpretation of enzyme effects on substrates we have started studies with transmission electron microscopy (TEM) where we aim to study enzyme binding to the cellulose and lignin parts of the substrate. Studies of enzymatic hydrolysis of steam pretreated spruce have been done to clarify the reasons for the drastic reduction on hydrolysis rate in the later stage of hydrolysis. Results show that the hydrolysis rate for the enzymes CBHI and EGI is reduced to 10% of the initial rate already after 60 min. Additions of fresh enzymes to the hydrolysed substrate leads to increased hydrolysis rate. Our conclusion is that the enzymes become unproductively bound to the substrate during the course of hydrolysis which leads to reduction of the effective enzyme concentration. In studies of the synergy between CBHI and EGI we have observed that the synergy between the enzymes is increasing during the hydrolysis, which can be explained by the increased need for the exo-enzyme CBHI to have access to free cellulose chain ends which can be formed by the action of endo glucanase I. This points to the possibility to increase the hydrolysis rate by addition of extra endo glucanase during the later stages of the hydrolysis. The adsorption of the enzymes on the lignin is of importance since the pretreated substrate is a lignocellulose complex. A strong adsorption to the lignin may reduce the amount of enzymes available for cellulose hydrolysis, and can reduce the possibilities for enzyme recycling. Our studies show that the central enzyme CBHI is strongly adsorbed to alkali extracted lignin and that the binding kinetics are fast.

Tjerneld, Folke [Lund univ., (Sweden). Dept. of Biochemistry

2000-06-01

239

Effect of peptide distribution on the fractionation of whey protein hydrolysates by nanofiltration membranes  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The fractionation of tryptic and chymotryptic hydrolysates of whey proteins by nanofiltration (NF) membranes has been investigated. Enzymatic hydrolysates were prepared by tryptic (TH) or chymotryptic (CH) hydrolysis of a commercial whey protein isolate followed by UF-treatment using a 10 000 g.mol$^{-1}$ MWCO in order to remove the enzyme and non-hydrolyzed material from the reaction mixture. Both hydrolysates were further fractionated using a SG13 (Osmonics) cellulose acetate NF membrane wi...

Pouliot, Yves; Gauthier, Sylvie; L Heureux, Jose?e

2000-01-01

240

Protein Hydrolysates from Agricultural Crops—Bioactivity and Potential for Functional Food Development  

Digital Repository Infrastructure Vision for European Research (DRIVER)

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 nutriti...

Callaghan, Yvonne C. O.; Brien, Nora M. O.; Mccarthy, Aoife L.

2013-01-01

 
 
 
 
241

Antihypertensive Properties on Spontaneously Hypertensive Rats of Peptide Hydrolysates from Silkworm Pupae Protein  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Peptide hydrolysates of silkworm pupae protein with molecular weight of less than 5000 Da were prepared by ultrafiltration. The extracted peptide hydrolysates of silkworm pupae protein had inhibitory action on angiotensin-I-converting enzyme activity in vitro. The hydrolysates were orally administered to spontaneously hypertensive rats (SHR) in one period and long-term (four weeks). The results showed that the systolic blood pressure (SBP) of the treatment grou...

Wei Wang,; Nan Wang; Yu Zhang

2014-01-01

242

Evaluation of sorghum straw hemicellulosic hydrolysate for biotechnological production of xylitol by Candida guilliermondii  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english A preliminary study on xylitol production by Candida guilliermondii in sorghum straw hemicellulosic hydrolysate was performed. Hydrolysate had high xylose content and inhibitors concentrations did not exceed the commonly found values in other hemicellulosic hydrolysates. The highest xylitol yield (0 [...] .44 g/g) and productivity (0.19 g/Lh) were verified after 72 hours.

L, Sene; P.V, Arruda; S.M.M, Oliveira; M.G.A, Felipe.

1141-11-01

243

[Hygienic characteristics of food hydrolysates made from small ocean fish and krill].  

Science.gov (United States)

A study was made of the biological value of acid and enzymatic hydrolysates from capelin, luminous anchovy and krill. Hydrolysates were obtained with the use of protosubtilin G-10-X or hydrochloric acid. The products were found to contain 39 to 64% of "crude" protein, with about 40% of total nitrogen belonging to non-protein one, 0.47-2.07% of lipids, 29.7-54.3% of mineral substances including 26.6-52.4% of sodium chloride. All the hydrolysates were limited in tryptophan, the deficiency being more demonstrable in acid hydrolysates. Enzymatic hydrolysate from luminous anchovy was rich in sulfur-containing amino acids (score 112%), whereas the remaining products were marked by their deficiency (score 53-90%). The products were rich in lysine, leucine, isoleucine, and aromatic amino acids. The anabolic efficacy was discovered to be the highest for enzymatic hydrolysate from luminous anchovy, exceeding the analogous characteristics for casein. The biological value of hydrolysate from capelin and krill was lower than that of casein. This was supported by the amino acid analysis data. The assimilability of all hydrolysates was established as fairly high. Hydrolysates are employed for manufacturing broth bricks and pastes. PMID:4082514

Solomko, G I; Prudnikova, L V; Prokopenko, O V; Orlova, T A

1985-01-01

244

Protein Hydrolysates from Agricultural Crops—Bioactivity and Potential for Functional Food Development  

Directory of Open Access Journals (Sweden)

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.

Yvonne C. O'Callaghan

2013-02-01

245

Spent fuel storage racks  

International Nuclear Information System (INIS)

Purpose: To decrease a spent fuel storage area occupied in a storage pool by increasing the storage density of the spent fuel, thereby enabling semi-permanent storage. Constitution: A framework of a spent fuel storage racks is made of stainless steel; and cells for holding fuel rod assemblies are formed by fitting, in its wall surface, ceramic tiles produced by sintering a mixture of such medium materials as Al2O3, SiO2, and ZrO2 and such elements as Eu, Hf, Gd, Sm, Co and Rh used as neutron absorbers which emit gamma rays in the process of reaction to neutrons. The most desirable neutron absorber to be used is Hf which has a high neutron absorbing capacity and a long half-life, is capable of keeping on absorbing neutrons even after neutron absorption, and makes (n,?) neutron absorption reaction, emitting gamma rays without accompanying any change of the ceramic tiles with time. (Sekiya, K.)

246

Spent fuel pyroprocessing demonstration  

International Nuclear Information System (INIS)

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

247

Spent fuel reprocessing options  

International Nuclear Information System (INIS)

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

248

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

Science.gov (United States)

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

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

2014-11-01

249

Radical scavenging and reducing ability of tilapia (Oreochromis niloticus) protein hydrolysates.  

Science.gov (United States)

Enzymatically hydrolyzed fish protein hydrolysates could be used as a source of antioxidative nutraceuticals. In our current work, we have investigated alkali-solubilized tilapia ( Oreochromis niloticus) protein hydrolysates for their ability to scavenge reactive oxygen species (ROS) and for their reducing power. Tilapia protein isolate was prepared by an alkaline solubilization technique and used as a substrate for enzyme hydrolysis. Cryotin, protease A 'Amano' 2, protease N 'Amano', Neutrase and Flavourzyme, were used separately to determine their effectiveness in hydrolyzing tilapia protein isolate. ROS scavenging ability was quantified using an isoluminol enhanced chemiluminescent assay in the presence of a) hydrogen peroxide or b) mononuclear cells isolated from human blood. Ferric reducing antioxidant power (FRAP) and Trolox equivalent antioxidant capacity (TEAC) of the hydrolysates using 2, 2'-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) or 2,2'-azinobis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS), were also investigated. Results showed that, in general, the TEAC, FRAP values and ROS scavenging ability of the hydrolysates increased with an increase in the degree of hydrolysis. Among the different hydrolysates, those prepared using Cryotin were most effective and Amano A2 hydrolysates were least effective in scavenging ABTS*(+) and ROS generated by hydrogen peroxide. However, FRAP assay showed that hydrolysates prepared using Flavourzyme were most effective, and Amano N and Neutrase hydrolysates were least effective in reducing ferric ions. No significant difference was observed among the hydrolysates produced with different enzymes in their ability to scavenge ROS generated by phorbol myristate acetate stimulated mononuclear cells. These results shed light on the in vitro ROS scavenging ability of alkali solubilized tilapia protein hydrolysates, as well as potential nutraceutical use of these hydrolysates. PMID:18828605

Raghavan, Sivakumar; Kristinsson, Hordur G; Leeuwenburgh, Christiaan

2008-11-12

250

Spent fuel storage. Facts booklet  

Energy Technology Data Exchange (ETDEWEB)

In October 1977, the Department of Energy (DOE) announced a spent nuclear fuel policy where the Government would, under certain conditions, take title to and store spent nuclear fuel from commercial power reactors. The policy is intended to provide spent fuel storage until final disposition is available. DOE has programs for providing safe, long-term disposal of nuclear waste. The spent fuel storage program is one element of waste management and compliments the disposal program. The costs for spent fuel services are to be fully recovered by the Government from the utilities. This will allow the utilities to confidently consider the costs for disposition of spent fuel in their rate structure. The United States would also store limited amounts of foreign spent fuel to meet nonproliferation objectives. This booklet summarizes information on many aspects of spent fuel storage.

None

1980-04-01

251

Production, characterization and application of activated carbon from brewer’s spent grain lignin  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Different types of activated carbon were prepared by chemical activation of brewer’s 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, metalli...

Mussatto, Solange I.; Fernandes, Marcela; Rocha, George J. M.; O?rfa?o, Jose? J. M.; Teixeira, J. A.; Roberto, Ine?s Conceic?a?o

2010-01-01

252

FRACTIONATION OF LIGNOCELLULOSIC BIOMASS FOR FUEL-GRADE ETHANOL PRODUCTION  

Energy Technology Data Exchange (ETDEWEB)

PureVision Technology, Inc. (PureVision) of Fort Lupton, Colorado is developing a process for the conversion of lignocellulosic biomass into fuel-grade ethanol and specialty chemicals in order to enhance national energy security, rural economies, and environmental quality. Lignocellulosic-containing plants are those types of biomass that include wood, agricultural residues, and paper wastes. Lignocellulose is composed of the biopolymers cellulose, hemicellulose, and lignin. Cellulose, a polymer of glucose, is the component in lignocellulose that has potential for the production of fuel-grade ethanol by direct fermentation of the glucose. However, enzymatic hydrolysis of lignocellulose and raw cellulose into glucose is hindered by the presence of lignin. The cellulase enzyme, which hydrolyzes cellulose to glucose, becomes irreversibly bound to lignin. This requires using the enzyme in reagent quantities rather than in catalytic concentration. The extensive use of this enzyme is expensive and adversely affects the economics of ethanol production. PureVision has approached this problem by developing a biomass fractionator to pretreat the lignocellulose to yield a highly pure cellulose fraction. The biomass fractionator is based on sequentially treating the biomass with hot water, hot alkaline solutions, and polishing the cellulose fraction with a wet alkaline oxidation step. In September 2001 PureVision and Western Research Institute (WRI) initiated a jointly sponsored research project with the U.S. Department of Energy (DOE) to evaluate their pretreatment technology, develop an understanding of the chemistry, and provide the data required to design and fabricate a one- to two-ton/day pilot-scale unit. The efforts during the first year of this program completed the design, fabrication, and shakedown of a bench-scale reactor system and evaluated the fractionation of corn stover. The results from the evaluation of corn stover have shown that water hydrolysis prior to alkaline hydrolysis may be beneficial in removing hemicellulose and lignin from the feedstock. In addition, alkaline hydrolysis has been shown to remove a significant portion of the hemicellulose and lignin. The resulting cellulose can be exposed to a finishing step with wet alkaline oxidation to remove the remaining lignin. The final product is a highly pure cellulose fraction containing less than 1% of the native lignin with an overall yield in excess of 85% of the native cellulose. This report summarizes the results from the first year's effort to move the technology to commercialization.

F.D. Guffey; R.C. Wingerson

2002-10-01

253

Debittering of Protein Hydrolysates by Lactobacillus LBL-4 Aminopeptidase  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Yoghurt strain Lactobacillus LBL-4 cultivated for 8–10?h at pH ~6.0 was investigated as a considerable food-grade source of intracellular aminopeptidase. Cell-free extract manifesting >200?AP U/l was obtained from cells harvested from 1?L culture media. Subtilisin-induced hydrolysates of casein, soybean isolate, and Scenedesmus cell protein with degree of hydrolysis 20–22% incubated at 45°C for 10?h by 10 AP?U/g peptides caused an enlarging of DH up to 40–42%, 46–48%, and 3...

Tchorbanov, Bozhidar; Marinova, Margarita; Grozeva, Lydia

2011-01-01

254

Desalting Fish Skin Protein Hydrolysates Using Macroporous Adsorption Resin  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Macroporous Adsorption Resin (MAR) DA 201-C was used to desalt different Fish Skin Protein Hydrolysates (FSPHs). The FSPHs were obtained by hydrolysis of fish skin using Alcalase in a batch reactor a 60°C and pH 8.25. The ash was removed by adsorbing FSPHs onto MAR. Desorption was achieved by washing with alcohol at different concentrations. Ash content of the FSPHs was reduced from 4.69-5.57 to 1.07-2.48% range. The protein content was enriched from 89.07-90.82 to 94.89-96.38% range. MAR ha...

Joseph Wasswa; Jian Tang; Xiao-Hong Gu

2007-01-01

255

Production of Defatted Palm Kernel Cake Protein Hydrolysate as a Valuable Source of Natural Antioxidants  

Directory of Open Access Journals (Sweden)

Full Text Available The aim of this study was to produce a valuable protein hydrolysate from palm kernel cake (PKC for the development of natural antioxidants. Extracted PKC protein was hydrolyzed using different proteases (alcalase, chymotrypsin, papain, pepsin, trypsin, flavourzyme, and bromelain. Subsequently, antioxidant activity and degree of hydrolysis (DH of each hydrolysate were evaluated using DPPH• radical scavenging activity and O-phthaldialdehyde spectrophotometric assay, respectively. The results revealed a strong correlation between DH and radical scavenging activity of the hydrolysates, where among these, protein hydrolysates produced by papain after 38 h hydrolysis exhibited the highest DH (91 ± 0.1% and DPPH• radical scavenging activity (73.5 ± 0.25% compared to the other hydrolysates. In addition, fractionation of the most effective (potent hydrolysate by reverse phase high performance liquid chromatography indicated a direct association between hydrophobicity and radical scavenging activity of the hydrolysates. Isoelectric focusing tests also revealed that protein hydrolysates with basic and neutral isoelectric point (pI have the highest radical scavenging activity, although few fractions in the acidic range also exhibited good antioxidant potential.

Mohammad Zarei

2012-06-01

256

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

Directory of Open Access Journals (Sweden)

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.

Yongsheng Ma

2014-10-01

257

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

CERN Document Server

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...

Cheng, Zhe; Zhang, Lei; Wang, Xinwei

2014-01-01

258

Complex Physiology and Compound Stress Responses during Fermentation of Alkali-Pretreated Corn Stover Hydrolysate by an Escherichia coli Ethanologen  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The physiology of ethanologenic Escherichia coli grown anaerobically in alkali-pretreated plant hydrolysates is complex and not well studied. To gain insight into how E. coli responds to such hydrolysates, we studied an E. coli K-12 ethanologen fermenting a hydrolysate prepared from corn stover pretreated by ammonia fiber expansion. Despite the high sugar content (?6% glucose, 3% xylose) and relatively low toxicity of this hydrolysate, E. coli ceased growth long before glucose was depleted....

Schwalbach, Michael S.; Keating, David H.; Tremaine, Mary; Marner, Wesley D.; Zhang, Yaoping; Bothfeld, William; Higbee, Alan; Grass, Jeffrey A.; Cotten, Cameron; Reed, Jennifer L.; Da Costa Sousa, Leonardo; Jin, Mingjie; Balan, Venkatesh; Ellinger, James; Dale, Bruce

2012-01-01

259

Feasibility study of energy use for densificated lignocellulosic material (briquettes)  

Energy Technology Data Exchange (ETDEWEB)

A study is made of a series of briquettes made from forest or industrial waste, some types of which have not to date been used in briquettes. They are evaluated from both an energy and economic viewpoint. Lignocellulosic densification improves the birquettes' behavior as a fuel by increasing the homogeneity and by being easier to transport and manage. Lignocellulosic binderless briquettes' characteristic net heating value (LHV) and remaining amount of fuel during combustion (Weight) have been investigated to obtain a general expression function of production and raw material factors. In both cases the main factor is the fixed carbon in a quadratic way as all the factors are easily measurable. 36 refs., 6 figs., 6 tabs.

Tabares, J.L.M.; Ortiz, L.; Granada, E.; Viar, F.P. [Technical School of Industrial Engineering, Vigo (Spain)

2000-08-01

260

Flow-through biological conversion of lignocellulosic biomass  

Energy Technology Data Exchange (ETDEWEB)

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.

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

2014-07-01

 
 
 
 
261

Canonical correlations between chemical and energetic characteristics of lignocellulosic wastes  

Directory of Open Access Journals (Sweden)

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.

Thiago de Paula Protásio

2012-09-01

262

Anaerobic Biodegradation of the Lignin and Polysaccharide Components of Lignocellulose and Synthetic Lignin by Sediment Microflora †  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Specifically radiolabeled [14C-lignin]lignocelluloses and [14C-polysaccharide]lignocelluloses were prepared from a variety of marine and freshwater wetland plants including a grass, a sedge, a rush, and a hardwood. These [14C]lignocellulose preparations and synthetic [14C]lignin were incubated anaerobically with anoxic sediments collected from a salt marsh, a freshwater marsh, and a mangrove swamp. During long-term incubations lasting up to 300 days, the lignin and polysaccharide components o...

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

1984-01-01

263

The NILE project : advances in the conversion of lignocellulosic materials into ethanol.  

Digital Repository Infrastructure Vision for European Research (DRIVER)

NILE ("New Improvements for Lignocellulosic Ethanol") was an integrated European project (2005-2010) devoted to the conversion of ligno-cellulosic 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 environmen...

Monot, F.; Margeot, A.; Hahn-ha?gerdal, B.; Lindstedt, J.; Slade, R.

2013-01-01

264

Exploiting the inter-strain divergence of Fusarium oxysporum for microbial bioprocessing of lignocellulose to bioethanol  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Microbial bioprocessing of lignocellulose to bioethanol still poses challenges in terms of substrate catabolism. A targeted evolution-based study was undertaken to determine if inter-strain microbial variability could be exploited for bioprocessing of lignocellulose to bioethanol. The microorganism studied was Fusarium oxysporum because of its capacity to both saccharify and ferment lignocellulose. Strains of F. oxysporum were isolated and assessed for their genetic variability. Using optimis...

Ali, Shahin S.; Khan, Mojibur; Fagan, Brian; Mullins, Ewen; Doohan, Fiona M.

2012-01-01

265

Production and use of lignocellulosic bioethanol in Europe: Current situation and perspectives  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Contrary to the case of the United States where a systematic management of the RD&D on lignocellulosic ethanol prevails, in Europe the research works remain fragmented despite the efforts made by the European Union and in few member states. In most of the European countries, sustainable lignocellulosic resources may not be widely available in the future for bioethanol production due to the possible competition between several potential usages. Thus the actual deployment of the lignocellulosic...

Gnansounou, Edgard

2010-01-01

266

Antioxidant activity of bovine casein hydrolysates produced by Ficus carica L.-derived proteinase.  

Science.gov (United States)

A Ficus carica L. latex proteinase preparation was investigated for its ability to produce antioxidant hydrolysates/peptides from bovine casein (CN). The Oxygen Radical Absorbance Capacity (ORAC) values for NaCN and ?-CN hydrolysates ranged from 0.06 to 0.18, and from 0.51 to 1.19?mol Trolox equivalents/mg freeze-dried sample, respectively. Gel permeation HPLC showed that the ?-CN hydrolysate with a degree of hydrolysis of 21% had 65% of peptide material with a molecular mass <500Da. The RP-UPLC profiles also indicated that ?-CN was substantially hydrolysed during the early stages of hydrolysis. Analysis of the 4h ?-CN hydrolysate by LC-ESI-MS/MS allowed identification of 8 peptide sequences with potential antioxidant properties. PMID:24629973

Di Pierro, Giovanna; O'Keeffe, Martina B; Poyarkov, Alexey; Lomolino, Giovanna; FitzGerald, Richard J

2014-08-01

267

Temperature-dependent FTIR spectra of collagen and protective effect of partially hydrolysed fucoidan  

Science.gov (United States)

FTIR spectra of collagen (PC) and partially hydrolysed fucoidan (PHF) incorporated into collagen films were investigated at different temperatures between 20 °C and 100 °C. Changes within the bands of amide I, amide II and amide III may indicate stabilization of collagen by hydrogen bonds during its interaction with partially hydrolysed fucoidan. Spectroscopic studies revealed that partially hydrolysed fucoidan was bound to the collagen without affecting its triple helicity. Interactions of fucoidan with H2SO4 (mild acid hydrolysis), leading to changes of the sulphated band positions in the 800-590 cm-1 region of IR spectra were observed. The effect of partially hydrolysed fucoidan on glucose-mediated collagen glycation and cross-linking of proteins in vitro was evaluated. It was observed that partially hydrolysed fucoidan incorporated into collagen films can be used as therapeutically active biomaterials that speed up the process of wound healing and may increase the anticancer activity of fucoidan.

Pielesz, Anna

2014-01-01

268

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

Directory of Open Access Journals (Sweden)

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.

Adamovi? Milan J.

2007-01-01

269

Lignocellulosic biomass utilization toward biorefinery : technologies, products and perspectives  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Lignocellulosic biomass wastes (LBW) are generated and accumulated in large amounts around the world every year. The disposal of large amounts of such wastes in the nature may cause environmental problems, affecting the quality of the soil, lakes and rivers. In order to avoid these problems, efforts have been directed to use LBW in a biorefinery to maximize the reutilization of these wastes with minimal or none production of residual matter. Through biorefiner...

Mussatto, Solange I.

2014-01-01

270

Role of lignin in the enzymatic hydrolysis of lignocellulose  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Characterization, understanding and overcoming barriers of enzymatic hydrolysis of different raw materials is essential for the development of economically competitive processes based on enzymatic treatments. This work focused on factors relevant for the improvement of enzymatic hydrolysis of lignocellulose raw materials derived from softwood. The major interest of the work was in lignin. Specific areas addressed were the role of lignin in the unproductive binding of cellulases, which restric...

Palonen, Hetti

2004-01-01

271

STEAM EXPLOSION : PROCESS AND IMPACT ON LIGNOCELLULOSIC MATERIAL  

Digital Repository Infrastructure Vision for European Research (DRIVER)

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...

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

2012-01-01

272

EVALUATION OF DIFFERENT APPROACHES FOR THE DRYING OF LIGNOCELLULOSE RESIDUES  

Digital Repository Infrastructure Vision for European Research (DRIVER)

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...

Carolina Tenorio; Roger Moya

2012-01-01

273

Energy and Environmental Performance of Bioethanol from Different Lignocelluloses  

Digital Repository Infrastructure Vision for European Research (DRIVER)

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...

Gjalt Huppes; Ester van der Voet; Lin Luo

2010-01-01

274

Fungal treated lignocellulosic biomass as ruminant feed ingredient: A review.  

Science.gov (United States)

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

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

2014-11-01

275

A method for rapid determination of sugars in lignocellulose prehydrolyzate  

Digital Repository Infrastructure Vision for European Research (DRIVER)

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 ...

Congcong Chi; Hou-min Chang; Zhijian Li; Hasan Jameel,; Zeng Zhang

2013-01-01

276

The nutritional value of protein-hydrolysed formulae.  

Science.gov (United States)

ABSTRACT Allergy to cow's milk proteins is a challenging condition in early infancy. Allergic infants may be predisposed to impairments of growth for either the disease itself or the nutritional constraints of the exclusion diet they should follow. Formulae based on extensively hydrolysed cow's milk proteins are widely used, representing therapy, and constituting 100% nutrient source in the first 4 to 6 months of life and half the daily nutrient intake in the second semester of life. In some cases these products are used also for preventive purposes. Some impairments in growth have been reported for infants using these products, even if mostly limited to the first year of life, with no apparent consequences at either medium- or long-term. The macronutrient content of infant formulae based on protein hydrolysates, whichever the source, should carefully be tested not only as far optimal utilization of nitrogenous sources but also the nature and metabolic fate of non-nitrogen caloric sources, represented by carbohydrates and fats, and micronutrients, particularly iron. It is recommended that studies aimed at the allergologic effects of these products include also an appropriate nutritional evaluation to conclude on their efficiency. PMID:24940610

Agostoni, Carlo; Terracciano, Luigi; Varin, Elena; Fiocchi, Alessandro

2014-06-18

277

Techno-economic analysis of lignocellulosic ethanol: A review.  

Science.gov (United States)

Lignocellulosic ethanol is expected to be commercialised during the next decade as renewable energy for transport. Competiveness with first generation bioethanol and with gasoline is commonly considered in techno-economic analyses for commercial stage. Several existing reviews conclude about the high spread of current and projected production costs of lignocellulosic ethanol due to the significant differences in assumptions concerning the following factors: composition and cost of feedstock, process design, conversion efficiency, valorisation of co-products, and energy conservation. Focusing on the studies in the United States of America and in Europe, the present review investigates the different natures of the techno-economic evaluations during the development process of the supply chain i.e., standard costing with respect to Value Engineering, and Target Costing based on the projected market price. The paper highlights the significant contribution of feedstock to the lignocellulosic ethanol production cost and the need to consider competition between different uses for resources. It is recommended the use of a value-based approach that considers sustainability characteristics and potential competition for resources complementarily to Target Costing and Value Engineering. PMID:20206505

Gnansounou, Edgard; Dauriat, Arnaud

2010-07-01

278

Proteins for breaking barriers in lignocellulosic bioethanol production.  

Science.gov (United States)

Reduction in fossil fuel consumption by using alternate sources of energy is a major challenge facing mankind in the coming decades. Bioethanol production using lignocellulosic biomass is the most viable option for addressing this challenge. Industrial bioconversion of lignocellulosic biomass, though possible now, is not economically viable due to presence of barriers that escalate the cost of production. As cellulose and hemicellulose are the major constituents of terrestrial biomass, which is available in massive quantities, hydrolysis of cellulose and hemicellulose by the microorganisms are the most prominent biochemical processes happening in the earth. Microorganisms possess different categories of proteins associated with different stages of bioethanol production and a number of them are already found and characterized. Many more of these proteins need to be identified which suit the specificities needed for the bioethanol production process. Discovery of proteins with novel specificities and application of genetic engineering technologies to harvest the synergies existing between them with the aim to develop consolidated bioprocess is the major direction of research in the future. In this review, we discuss the different categories of proteins used for bioethanol production in the context of breaking the barriers existing for the economically feasible lignocellulosic bioethanol production. PMID:25692949

Ulaganathan, Kandasamy; Goud, Burragoni S; Reddy, Mettu M; Kumar, Vanaparthi P; Balsingh, Jatoth; Radhakrishna, Surabhi

2015-01-01

279

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

DEFF Research Database (Denmark)

Proteins from fish tissue could be a promising source of peptides with a nutritional and pharmaceutical value, e.g. as treatment of type 2 diabetes with dipeptidyl peptidase IV (DPP-IV) inhibiting peptides, and could be used in health and functional foods and thereby increasing the value of 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) inhibiting properties. 10kDa dialysis bags containing 10ml water were added to homogenized fish tissues, which were subsequently hydrolysed for 24 hours at 37?C and pH 8 with intestinal mucosa extract and/or pancreatin solution from pig. Dialysis bags were then removed and content were analyzed for free 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 antioxidative capacity in belly flap hydrolysates. No difference between hydrolysates with pancreatin and pancreatin+mucosa was observed. Hydrolysates will be further fractionated by gelfiltration. Fractions will be analyzed for the three bioactivities and also presented.

Falkenberg, Susan Skanderup; Stagsted, Jan

280

Spent fuel storage rack  

International Nuclear Information System (INIS)

In a spent fuel storage rack using a boron-containing austenite stainless steel, the stainless steel for use in the storage rack is adapted to have specific constitutional ingredients of: 0.5 ? x ? 1, and -34.4 x +53.2 ? y -80 x +120 assuming 'x' as wt% of boron in stainless steel to be added to the stainless steel, 'y' as wt% of 10B contained in the entire amount of the added boron. This can facilitate rolling of the stainless steel and lower the sensitivity of high-temperature crackings upon welding, as well as improve storage efficiency for spent fuel assemblies while mitigating possibility of degradation of materials upon neutron irradiation. (T.M.)

 
 
 
 
281

Spent fuel shipping casks  

International Nuclear Information System (INIS)

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)

282

Encapsulating spent nuclear fuel  

International Nuclear Information System (INIS)

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)

283

Spent fuel storage rack  

International Nuclear Information System (INIS)

The present invention provides a storage rack capable of improving fuel storage density of spent fuel assemblies generated in a BWR type power plant. In the spent storage rack, a plurality of storage cells for containing fuel assemblies one by one are constituted by shielding members, the shielding member is made of stainless steel containing 1wt% of more of boron, and the shielding member is determined up to nominal 5mm thickness. An austenite stainless steel plate to which boron is added at a high concentration acts so as to make the arrangement of the fuel rack cells regular square lattice have the geometrically highest density, and acts so as to reduce the distance between fuel rack cell and the stored fuels by absorbing thermal neutrons generated from the spent fuels. The plate having up to nominal 5mm thickness makes the voids present in the material finer during ordinary rolling and acts so as to provide mechanical properties required as a fuel rack. (I.S.)

284

Spent fuel dissolution mechanisms  

International Nuclear Information System (INIS)

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.)

285

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

Directory of Open Access Journals (Sweden)

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 ?-glucosidase (?G; 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, ?-xylosidase (L?X; GH family 52, ?-arabinofuranosidase (LArb, GH family 51 and ?-glucuronidase (L?Gl, 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. L?X (0.6 mg/g glucan is crucial to obtaining monomeric xylose (54% xylose yield, while LArb (0.6 mg/g glucan and L?Gl (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.

Hermanson Spencer

2011-02-01

286

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

Directory of Open Access Journals (Sweden)

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.

Mari Silvia Rodrigues de Oliveira

2014-02-01

287

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

Science.gov (United States)

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 37°C. 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.

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

2013-11-01

288

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

Directory of Open Access Journals (Sweden)

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 ?molGly/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.

Aleksandra Zambrowicz

2012-12-01

289

Cellulosic hydrolysate toxicity and tolerance mechanisms in Escherichia coli  

Directory of Open Access Journals (Sweden)

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.

Gill Ryan T

2009-10-01

290

[Short peptide fragments with antiulcer activity from a collagen hydrolysate].  

Science.gov (United States)

A peptide acidic hydrolysate of collagen (PHC) was obtained under conditions (4 N HCl) ensuring the predominant formation of short peptides, glyprolines. They were separated and their antiulcer activity was studied. Thirty individual peptides with molecular masses of 174-420 amu were isolated from the PHC by HPLC. The PHC was shown to predominantly contain 2- to 4-aa peptides, including PG, GP, and PGP. Experiments on rats demonstrated that, on intragastric administration at a dose of 1 mg/kg, PHC enhances the stability of the gastric mucosa to the action of ulcerogenic factors, such as ethanol and stress, and exhibits a protecting antiulcer effect. Even a lesser dose (0.1 mg/kg), which reduced ulcer area twofold, was effective in the stress model of ulcer formation. The intraperitoneal and intragastric administration of PHC at a dose of 1 mg/kg was found to exhibit a therapeutic effect in the acetate model of ulcer formation. PMID:16637291

Zolotarev, Iu A; Badmaeva, K E; Bakaeva, Z V; Samonina, G E; Kopylova, G N; Dadaian, A K; Zverkov, Iu B; Garanin, S K; Vas'kovski?, B V; Ashmarin, I P; Miasoedov, N F

2006-01-01

291

Enhancement of glycerol production with ram horn hydrolysate by yeast  

International Nuclear Information System (INIS)

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

292

Identification of bitter peptides in whey protein hydrolysate.  

Science.gov (United States)

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 ?-lactalbumin, ?-lactoglobulin, serum albumin, and ?-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

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

2014-06-25

293

System and method for conditioning a hardwood pulp liquid hydrolysate  

Science.gov (United States)

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, hyrolyzes 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.

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

2013-12-17

294

Spent fuel storage in India  

International Nuclear Information System (INIS)

India has gone for closed nuclear fuel cycle option to reprocess the spent fuel for recovery of uranium and plutonium to meet energy demand. Wet storage of spent fuel has been the predominant mode of storage in India pending reprocessing. Three regional spent fuel storage facilities are being constructed at different reactor sites to meet the storage requirement. The paper describes important issues related to layout, design and licensing in addition to operating experience. (author)

295

Effects of gamma irradiation on the decomposition and biodegradability of lignocellulose  

International Nuclear Information System (INIS)

The study of effects of a pretreatment by gamma radiation on radioactive lignocellulose from poplar-tree and on subsequent biodegradation by fungi is realized for residues and soluble products. Measurement before and after treatment, of cellulose accessibility to an exogen cellulase shows the interest of irradiation in transformation processes of lignocellulosic products

296

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

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, differe...

Krystian Miazek; Claire Remacle; Aurore Richel; Dorothee Goffin

2014-01-01

297

Spent fuel reprocessing optimisation  

Energy Technology Data Exchange (ETDEWEB)

In most countries, the back end solution is not yet defined. In the meantime, the spent fuel assemblies are stored on site. But the pool capacity is usually not able to admit the total amount of spent fuel produced along the whole life of the plant. The only realistic solution to avoid the building of new capacities is the reprocessing. In this case, the owner has a huge amount of assemblies at his disposal, with various enrichments, burnups and cooling times. This aims to show that the reprocessing strategy can be optimized: the order the owner will choose to reprocess these assemblies has a huge impact on the amount and quality of Pu and on the quality of reprocessed U that will come back from the reprocessing and hence on the global balance in terms of natural Uranium and SWU. An analysis tool has been developed by GDF-Suez, its application on the assemblies stored on the Belgian plants is presented as an example, and the results discussed. (authors)

Druenne, H. [Tractebel Engineering S.A. (GDF-SUEZ), Avenue Ariane 7, 1200 Brussels (Belgium)

2010-07-01

298

Spent fuel reprocessing optimisation  

International Nuclear Information System (INIS)

In most countries, the back end solution is not yet defined. In the meantime, the spent fuel assemblies are stored on site. But the pool capacity is usually not able to admit the total amount of spent fuel produced along the whole life of the plant. The only realistic solution to avoid the building of new capacities is the reprocessing. In this case, the owner has a huge amount of assemblies at his disposal, with various enrichments, burnups and cooling times. This aims to show that the reprocessing strategy can be optimized: the order the owner will choose to reprocess these assemblies has a huge impact on the amount and quality of Pu and on the quality of reprocessed U that will come back from the reprocessing and hence on the global balance in terms of natural Uranium and SWU. An analysis tool has been developed by GDF-Suez, its application on the assemblies stored on the Belgian plants is presented as an example, and the results discussed. (authors)

299

Spent fuel storage rack  

International Nuclear Information System (INIS)

The structure of a spent fuel storage rack is determined by the material, thickness, size of square cylindrical tubes (the gap between spent fuel assemblies and the square cylindrical tubes) and pitch of the arrangement (the gap between each of the square cylindrical tubes). In the present invention, the thickness and the pitch of the arrangement of the square tubes are optimized while evaluating subcriticality. Namely, when the sum of the thickness of the water gap at the outer side (the pitch of arrangement of the cylindrical tubes) and the thickness of the cylindrical tubes is made constant, the storage rack is formed by determining the thickness of the cylindrical tubes which is smaller than the optimum value among the combination of the thickness of the water gap at the outer side and that of the cylindrical tube under the effective multiplication factor to be performed. Then, the weight of the rack can be reduced, and the burden of the load on the bottom of the pool can be reduced. Further, the amount of the constitutional materials of the rack itself can be reduced thereby capable of reducing the cost for the materials of the rack. (T.M.)

300

Cellulosic ethanol: progress towards a simulation model of lignocellulosic biomass  

International Nuclear Information System (INIS)

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

 
 
 
 
301

Ethanol Production from Nondetoxified Dilute-Acid Lignocellulosic Hydrolysate by Cocultures of Saccharomyces cerevisiae Y5 and Pichia stipitis CBS6054  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Saccharomyces cerevisiae Y5 (CGMCC no. 2660) and Issatchenkia orientalis Y4 (CGMCC no. 2159) were combined individually with Pichia stipitis CBS6054 to establish the cocultures of Y5 + CBS6054 and Y4 + CBS6054. The coculture Y5 + CBS6054 effectively metabolized furfural and HMF and converted xylose and glucose mixture to ethanol with ethanol concentration of 16.6?g/L and ethanol yield of 0.46?g ethanol/g sugar, corresponding to 91.2% of the maximal theoretical value in synthetic medium. A...

Ping Wan; Dongmei Zhai; Zhen Wang,; Xiushan Yang; Shen Tian

2012-01-01

302

Partially hydrolysed guar gum supplemented comminuted chicken diet in persistent diarrhoea: a randomised controlled trial  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Background: Partially hydrolysed guar gum (Benefiber) added to a diet is fermented in the colon, producing short chain fatty acids, which improve intestinal function, including colonic salt and water absorption.

Alam, N.; Meier, R.; Sarker, S.; Bardhan, P.; Schneider, H.; Gyr, N.

2005-01-01

303

Radical scavenging and amino acid profiling of wedge clam, Donax cuneatus (Linnaeus) protein hydrolysates.  

Science.gov (United States)

Body, foot and viscera of Donax cuneatus (Linnaeus) were hydrolyzed using commercial proteases (pepsin, trypsin and papain) and tested for their antioxidant activity by DPPH scavenging ability and reducing power assays. In comparison between all the hydrolysates, papain viscera (28.513?±?0.165 & 0.186?±?0.008) and foot (33.567?±?0.132 & 0.166?±?0.013) hydrolysates showed highest DPPH and reducing power ability respectively. The active hydrolysates were purified with DEAE- cellulose followed by Sephadex G-25 columns connected to FPLC. Further, the isolated active fractions were loaded onto HPLC for their amino acid profiling and found with the presence of potential amino acids viz., histidine, cysteine, alanine etc. These results suggest that the isolated antioxidant peptide from viscera and foot hydrolysate of D. cuneatus can be used in treating human diseases where free radicals and oxidative damage are involved. PMID:25477664

Nazeer, R A; Saranya, M A V; Naqash, Shabeena Yousuf

2014-12-01

304

In Vitro Binding Capacity of Bile Acids by Defatted Corn Protein Hydrolysate  

Directory of Open Access Journals (Sweden)

Full Text Available Defatted corn protein was digested using five different proteases, Alcalase, Trypsin, Neutrase, Protamex and Flavourzyme, in order to produce bile acid binding peptides. Bile acid binding capacity was analyzed in vitro using peptides from different proteases of defatted corn hydrolysate. Some crystalline bile acids like sodium glycocholate, sodium cholate and sodium deoxycholate were individually tested using HPLC to see which enzymes can release more peptides with high bile acid binding capacity. Peptides from Flavourzyme defatted corn hydrolysate exhibited significantly (p

Pierre Claver Irakoze

2011-02-01

305

Systematic Investigation of Antioxidant Activity of Egg White Protein Hydrolysates Obtained by Pepsin  

Digital Repository Infrastructure Vision for European Research (DRIVER)

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 scavengin...

Shuguo Sun; Meihu Ma; Qinlu Lin; Tao Yang; Huihui Niu

2013-01-01

306

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

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, bro...

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

2007-01-01

307

Optimization of the Preparation of Fish Protein Anti-Obesity Hydrolysates Using Response Surface Methodology  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The enzymatic condition for producing the anti-obesity hydrolysates from fish water-soluble protein was optimized with the aid of response surface methodology, which also derived a statistical model for experimental validation. Compared with neutral protease, papain and protamex, the porcine pancreas lipase inhibitory rate of hydrolysates from fish water-soluble protein was higher with alkaline protease. Results showed that the model terms were significant, the terms of lack of fit were not s...

Jinju Wang; Chen Peng; Yanping Wang; Liyuan Liu

2013-01-01

308

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

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...

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

2011-01-01

309

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

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...

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

2013-01-01

310

Effect of Adsorption Medium, Hydrolytic Parameters and Ultrafiltration on the Phenylalanine Removal from Pancreatic Whey Hydrolysates  

Digital Repository Infrastructure Vision for European Research (DRIVER)

With the aim of producing dietary supplements for phenylketonurics, using whey hydrolysates as protein sources, the effect of some procedures over phenylalanine (Phe) removal was evaluated. Twelve whey hydrolysates were prepared by the action of a pancreatin, in three enzyme:substrate (E:S) ratios and two temperatures. Half of the samples were submitted to the ultrafiltration (UF) through 10,000 Da cut-off membranes. The activated carbon and the polymeric adsorbent XAD-4 were used for removin...

Delvivo, Fernanda M.; Vieira, Claudia R.; Biasutti, Eliza A. R.; Michely Capobiango; Silva, Viviane D. M.; Afonso, Wendel O.; Silvestre, Marialice P. C.

2006-01-01

311

Production of Lupinus angustifolius protein hydrolysates with improved functional properties  

Digital Repository Infrastructure Vision for European Research (DRIVER)

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 compar...

Mill N, Francisco; Vioque, Javier; Gir N-calle, Julio; Pedroche, Justo; Lqari, Hassane

2005-01-01

312

Determination of optimal regimes in obtaining kilka protein hydrolysates for sturgeon starter diets  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The aim of this study was to determine the optimal regimes of obtaining hydrolysates of minced fish (Clupeonella sp., kilka) with a predictable output of water-soluble protein and non-protein nitrogen compounds in them. The technological process has been studied by two types of raw material: whole fish and fish without head and entrails. Studying the process of obtaining kilka hydrolysates for sturgeon starter diets showed that the most rational way of hydrolysis in this case is enzymatic-aci...

Alamdari Hojatollah; Dolganova Natalia Vadimovna; Ponomarev Sergey Vladimirovich

2013-01-01

313

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

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...

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

2014-01-01

314

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

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 ...

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

2009-01-01

315

Collagen metabolism of human osteoarthritic articular cartilage as modulated by bovine collagen hydrolysates  

Digital Repository Infrastructure Vision for European Research (DRIVER)

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 ...

Schadow, Saskia; Siebert, Hans-christian; Lochnit, Gu?nter; Kordelle, Jens; Rickert, Markus; Steinmeyer, Ju?rgen

2013-01-01

316

Spent fuel storage  

International Nuclear Information System (INIS)

A space is formed underground by partitioning walls made of radiation shielding material, in which only a storage cell is contained. The storage cell comprises metal blocks made of a heat conductive material such as stainless steels. A great number of holes each having a predetermined diameter are vertically arranged to the metal block, and storage pits are constituted by the holes. Spent nuclear fuels are contained in a first columnar vessel and the first columnar vessel is further contained in a large second columnar vessel. Both of the first columnar vessel and the second columnar vessel are made of a durable metal material such as stainless steels. The second columnar vessel is inserted to the storage pit of the storage cell. With such a constitution, heat emitted from the second columnar vessel is transferred to the metal block by radiation and dissipated from the metal block. Accordingly, a heat dissipation efficiency can be increased. (I.N.)

317

Spent fuel cask  

International Nuclear Information System (INIS)

Purpose: To mount a contaminated gas purifier in a spent fuel cask, thereby to prevent scattering of gas during the handling operation of the cask. Constitution: One or more openings other than the fuel outlet port are provided in the cask, and valves are connected thereto. To the forward ends of the valves there is connected a gas trapping device and a circulating pump. Prior to opening the lid of the cask, the valves are opened, and the interior of the cask is maintained in a negative pressure. After the introduction of the contaminated gas within the cask to the outside of the cask, a replacement gas is introduced therein. After sufficiently repeating this procedure, the lid of the cask is opened, and operations such as taking out of fuel and the like are performed. (Sekiya, K.)

318

Spent fuel cask  

International Nuclear Information System (INIS)

A cask for containing spent nuclear fuel during transport. The cask has a pair of multiple element trunnions disposed on opposite sides of the cask adjacent the top thereof. The multiple elements of the trunnions provide separate and independent load paths for lifting the cask. The trunnions are removable and disassemblable to permit inspection of each element. Disposed on the ends of the cask are convex impact limiters for reducing forces applied to the cask in a collision. Apparatus engageable with the trunnions for lifting the cask thereby comprise a pair of multiple element laminated plates engageable with a crane hook. A pair of multiple element straps have ends selectively engageable with the plates and ends selectively engageable with the trunnions of the cask

319

Spent fuel storage rack  

International Nuclear Information System (INIS)

In a spent fuel storage rack comprising square cylinders arranged in a checkwise pattern and connected by way of metal pieces, when boron-containing stainless steels having neutron absorbing property and bending fabricability are used as a material for the square cylinder, coarse borides (Fe, Cr)2B are crystallized in a portion sensitive to the welding heat, to possibly reduce the flexibility. Then, the square cylinder is constituted by at least two metal layers comprising a continuous metal layer with good weldability at the outer circumference thereof and a continuous metal layer with good neutron absorbing property at the inner circumference thereof. By such a constitution, since the boron-containing stainless steel is free from the effect of heat higher than 1288degC, crystallization of coarse borides can be prevented and the impact shock resistance in the welded portion can be improved. (T.M.)

320

Transportation of spent fuel  

International Nuclear Information System (INIS)

The first edition of the IAEA's Regulations for the Safe Transport of Radioactive Materials was published as Safety Series No. 6 in 1961 and revised editions of Safety Series No. 6 were issued in 1964, 1967, 1973, 1979 and 1985. Beginning in 1986, the IAEA will issue a supplement to Safety Series No. 6 every two years. Three major changes in the 1985 edition could affect the transport of spent fuel in the future: release requirement on type B(U) package, deletion of fissile classes and adoption of a 200 m water immersion test for irradiated fuel casks. The next major revision of Safety Series No. 6 is not anticipated until 1995 or later

 
 
 
 
321

Detoxification of corncob acid hydrolysate with SAA pretreatment and xylitol production by immobilized Candida tropicalis.  

Science.gov (United States)

Xylitol fermentation production from corncob acid hydrolysate has become an attractive and promising process. However, corncob acid hydrolysate cannot be directly used as fermentation substrate owing to various inhibitors. In this work, soaking in aqueous ammonia (SAA) pretreatment was employed to reduce the inhibitors in acid hydrolysate. After detoxification, the corncob acid hydrolysate was fermented by immobilized Candida tropicalis cell to produce xylitol. Results revealed that SAA pretreatment showed high delignification and efficient removal of acetyl group compounds without effect on cellulose and xylan content. Acetic acid was completely removed, and the content of phenolic compounds was reduced by 80%. Furthermore, kinetic behaviors of xylitol production by immobilized C. tropicalis cell were elucidated from corncob acid hydrolysate detoxified with SAA pretreatment and two-step adsorption method, respectively. The immobilized C. tropicalis cell showed higher productivity efficiency using the corncob acid hydrolysate as fermentation substrate after detoxification with SAA pretreatment than by two-step adsorption method in the five successive batch fermentation rounds. After the fifth round fermentation, about 60 g xylitol/L fermentation substrate was obtained for SAA pretreatment detoxification, while about 30 g xylitol/L fermentation substrate was obtained for two-step adsorption detoxification. PMID:25133211

Deng, Li-Hong; Tang, Yong; Liu, Yun

2014-01-01

322

Production of Lactic Acid by a Local Isolate of Lactobacillus plantarum Using Cheap Starchy Material Hydrolysates  

Directory of Open Access Journals (Sweden)

Full Text Available Some cheap starchy materials like sorghum grains and wheat bran were degraded by crude glucoamylase of a local isolate of Mucor sp., then Lactic Acid (LA was produced by a local isolate of L. plantarum using sorghum flour hydrolysate, sorghum starch hydrolysate, soluble starch hydrolysate, wheat bran hydrolysate and date syrup with 10% reducing sugars. The yield of LA increased to 37.2 g/100 reducing sugars by using sorghum flour hydrolysate as a basal medium supplemented with (0.6+0.6% yeast extract+(NH42HPO4 and 0.06% MgSO4.7H2O, reducing sugars was 5%. The fermentation temperature was 30°C/96 h. Results indicated that using hydrolysates mixtures of sorghum flour and wheat bran improved LA fermentation. The yield of LA was 92.5 g by using sorghum flour and 50% wheat bran. Paper chromatography indicated that LA was the unique organic acid in the fermented broth.

Amal Kadhim G. Al-Asady

2012-01-01

323

Preparation of carbon molecular sieve from lignocellulosic biomass: A review  

Energy Technology Data Exchange (ETDEWEB)

A literature review on preparation of carbon molecular sieve (CMS) from lignocellulosic biomass is presented. The effect of various operation parameters such as pyrolytic temperature, flow rate of the carbonizing agent and time of pyrolysis on the carbonization of the lignocellulosic biomass as a carbon precursor was reviewed. Various physical and chemical processes for the activation of the biomass-based char and their effects on textural properties of the activated char were discussed. Conversion of activated chars to CMS as the final stage of the preparation process through different techniques of chemical vapor deposition (CVD) and controlled pyrolysis was assessed. Survey of literature revealed that production of CMS with BET surface area of 1247 m{sup 2}/g and micropore volume of 0.51 cm{sup 3}/g, under appropriate conditions has been reported. Also, maximum selectivity of 7.6 and 400 for separation of O{sub 2}/N{sub 2} and CO{sub 2}/CH{sub 4} was devoted to palm shell and coconut shell-based CMS, respectively. (author)

Mohamed, Abdul Rahman [School of Chemical Engineering, Engineering Campus, Universiti Sains Malaysia, 14300 Nibong Tebal, Penang (Malaysia); Mohammadi, Maedeh; Darzi, Ghasem Najafpour [Faculty of Chemical Engineering, Noushirvani University of Technology, Babol (Iran)

2010-08-15

324

Energy and Environmental Performance of Bioethanol from Different Lignocelluloses  

Directory of Open Access Journals (Sweden)

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.

Gjalt Huppes

2010-01-01

325

Covalent Immobilization of ?-Glucosidase on Magnetic Particles for Lignocellulose Hydrolysis  

DEFF Research Database (Denmark)

?-Glucosidase hydrolyzes cellobiose to glucose and is an important enzyme in the consortium used for hydrolysis of cellulosic and lignocellulosic feedstocks. In the present work, ?-glucosidase was covalently immobilized on non-porous magnetic particles to enable re-use of the enzyme. It was found that particles activated with cyanuric chloride and polyglutaraldehyde gave the highest bead-related immobilized enzyme activity when tested with p-nitrophenyl-?-D-glucopyranoside (104.7 and 82.2 U/g particles, respectively). Furthermore, the purified ?-glucosidase preparation from Megazyme gave higher bead-related enzyme activities compared to Novozym 188 (79.0 and 9.8 U/g particles, respectively). A significant improvement in thermal stability was observed for immobilized enzyme compared to free enzyme; after 5 h (at 65 °C), 36 % of activity remained for the former, while there was no activity in the latter. The performance and recyclability of immobilized ?-glucosidase on more complex substrate (pretreated spruce)was also studied. It was shown that adding immobilized ?-glucosidase (16 U/g dry matter) to free cellulases (8 FPU/g dry matter) increased the hydrolysis yield of pretreated spruce from ca. 44 % to ca. 65 %. In addition, it was possible to re-use the immobilized ?-glucosidase in the spruce and retain activity for at least four cycles. The immobilized enzyme thus shows promise for lignocellulose hydrolysis.

Alftrén, Johan; Hobley, Timothy John

2013-01-01

326

Enzymatic hydrolysis of lignocellulosic biomass from Onopordum nervosum.  

Science.gov (United States)

Some properties of the cellulolytic complex obtained from Trichoderma reesei QM 9414 grown on Solka floc as carbon source and its ability to hydrolyze the lignocellulosic biomass of Onopordum nervosum Boiss were studied. The optimum enzyme activity was found at temperatures between 50 and 55 degrees C and pH ranging from 4.3 to 4.8. Hydrolysis of 4-nitropnenyl-beta-D-glucopyranoside (4-NPG) and cellobiose by the beta-glucosidase of the complex, showed competitive inhibition by glucose with a K(i) value of 0.8 mM for 4-NPG and 2. 56 mM for cellobiose. Enzymatic hydrolysis yield of Onopordum nervosum, evaluated as glucose production after 48 h, showed a threefold increase by pretreating the lignocellulosic substrate with alkali. When the loss of glucose incurred by de pretreatment was taken into account, a 160% increase in the final cellulose to glucose conversion was found to be due to the pretreatment. PMID:18584755

Martín, C; Negro, M J; Alfonsel, M; Sáez, R

1988-07-20

327

Furfural--a promising platform for lignocellulosic biofuels.  

Science.gov (United States)

Furfural offers a promising, rich platform for lignocellulosic biofuels. These include methylfuran and methyltetrahydrofuran, valerate esters, ethylfurfuryl and ethyltetrahydrofurfuryl ethers as well as various C(10)-C(15) coupling products. The various production routes are critically reviewed, and the needs for improvements are identified. Their relative industrial potential is analysed by defining an investment index and CO(2) emissions as well as determining the fuel properties for the resulting products. Finally, the most promising candidate, 2-methylfuran, was subjected to a road trial of 90,000 km in a gasoline blend. Importantly, the potential of the furfural platform relies heavily on the cost-competitive production of furfural from lignocellulosic feedstock. Conventional standalone and emerging coproduct processes-for example, as a coproduct of cellulosic ethanol, levulinic acid or hydroxymethyl furfural-are expensive and energetically demanding. Challenges and areas that need improvement are highlighted. In addition to providing a critical review of the literature, this paper also presents new results and analysis in this area. PMID:22213717

Lange, Jean-Paul; van der Heide, Evert; van Buijtenen, Jeroen; Price, Richard

2012-01-01

328

A method for rapid determination of sugars in lignocellulose prehydrolyzate  

Directory of Open Access Journals (Sweden)

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.

Congcong Chi

2013-02-01

329

Disposal of spent nuclear fuel  

Energy Technology Data Exchange (ETDEWEB)

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.

1979-12-01

330

Spent fuel treatment in Japan  

International Nuclear Information System (INIS)

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)

331

Enhanced ethanol production by fermentation of rice straw hydrolysate without detoxification using a newly adapted strain of Pichia stipitis.  

Science.gov (United States)

An enhanced inhibitor-tolerant strain of Pichia stipitis was successfully developed through adaptation to acid-treated rice straw hydrolysate. The ethanol production obtained by fermentation of NaOH-neutralized hydrolysate without detoxification using the adapted P. stipitis was comparable to fermentation of overliming-detoxified hydrolysate. The ethanol yield using the adapted P. stipitis with both types of hydrolysate at pH 5.0 achieved 0.45 g(p) g(s)(-1), which is equivalent to 87% of the maximum possible ethanol conversion. Furthermore, the newly adapted P. stipitis demonstrated significantly enhanced tolerance to sulfate and furfural despite the fact that both inhibitors had not been removed from the hydrolysate by NaOH neutralization. Finally, the ethanol conversion could be maintained at 60% and above when the neutralized hydrolysate contained 3.0% sulfate and 1.3gL(-1) furfural. PMID:19349164

Huang, Chiung-Fang; Lin, Ting-Hsiang; Guo, Gia-Luen; Hwang, Wen-Song

2009-09-01

332

Hydrolysed wheat proteins present in cosmetics can induce immediate hypersensitivities.  

Science.gov (United States)

Cosmetics containing hydrolysed wheat proteins (HWP) can induce rare but severe allergic reactions. 9 patients, all females without common wheat allergy, but with contact urticaria to such cosmetics, were studied. 6 of them also experienced generalized urticaria or anaphylaxis to foods containing HWP. All patients had low to moderate levels of immunoglobulin (Ig)E specific of wheat flour (f4) or gluten (f79). Their sensitivity to HWP and their tolerance to unmodified wheat proteins extracted from grains were confirmed using skin tests. Immunoblotting analyses showed that IgE from all patients reacted with almost all HWP tested. Reactions generally occurred with large random peptide aggregates. IgE reacted also with unmodified grain proteins, which contrasted with skin tests results. They reacted always with salt soluble proteins but variably with gluten proteins. No reaction occurred with gliadins in patients without associated immediate hypersensitivity to food containing HWP. These results show the role of hydrolysis on the allergenicity of wheat proteins, both through skin or digestive routes. At least part of the epitopes involved is pre-existing in unmodified wheat proteins. The aggregation of peptide bearing these epitopes and others created by hydrolysis, along with the increased solubility and the route of exposure, are possible factors of the allergenicity of HWP. PMID:16689814

Laurière, Michel; Pecquet, Catherine; Bouchez-Mahiout, Isabelle; Snégaroff, Jacques; Bayrou, Olivier; Raison-Peyron, Nadia; Vigan, Martine

2006-05-01

333

Contact urticaria from protein hydrolysates in hair conditioners.  

Science.gov (United States)

Protein hydrolysates (PHs) are added to hair-care products (to "repair" broken hair), soaps, bath gels, creams, etc. From one to 22 PHs used in hair-care products (collagen, keratin, elastin, milk, wheat, almond, and silk) were tested in three patient groups: A) 11 hairdressers with hand dermatitis B) 2160 consecutive adults with suspected allergic respiratory disease subjected to routine skin prick tests C) 28 adults with atopic dermatitis. In group A, all the 22 PHs were tested with scratch and patch tests. In groups B and C, one to three PHs were tested with prick tests. Positive scratch/prick test reactions were seen in 12 patients from three PHs altogether. All were women with atopic dermatitis, and all reacted to at least hydroxypropyl trimonium hydrolyzed collagen (Crotein Q). In three patients, prick and open tests with a hair conditioner containing Crotein Q were performed with positive results. One patient reported contact urticaria on her hands, and two reported acute urticaria on their head, face, and upper body from a hair conditioner containing Crotein Q. In seven of the eight studied sera, specific IgE to Crotein Q was detected. In conclusion, PHs of hair cosmetics can cause contact urticaria, especially in patients with atopic dermatitis. PMID:9860241

Niinimäki, A; Niinimäki, M; Mäkinen-Kiljunen, S; Hannuksela, M

1998-11-01

334

ACID- AND BASE-CATALIZED HYDROLYSES OF CORN STALK  

Directory of Open Access Journals (Sweden)

Full Text Available Nowadays agricultural wastes represent an alternative source of renewable raw materials. Different processes can be applied to these alternative materials to separate their components and obtain chemical products with high added value, such as bioethanol, organic acids, monomers, and biopolymers. The main objective of this work is to study the extraction of hemicelluloses from corn stalks using different reagents [H2SO4, HNO3, HCL, CH3COOH, CF3COOH, Ca(OH2, NaOH]. The raw material was characterized and fractionated with autoclave hydrolysis processes (121 ºC, 1:20 solid/liquid ratio, 60 min, pH = 4 or 8. Monomeric sugars concentration, TDS, MO, MI, density, and final pH of the hydrolysate were determined. Hemicelluloses were precipitated and analyzed by different techniques (FTIR, TGA and GPC. The highest yield of hemicelluloses extraction was achieved by sulphuric acid (0.98 g/L total sugar content and the less effective reagent was Ca(OH2 (0.52 g/L total sugar content.

Cristina Sánchez

2011-04-01

335

Assessment of spent fuel cooling  

International Nuclear Information System (INIS)

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

336

Effect of Peptide Size on Antioxidant Properties of African Yam Bean Seed (Sphenostylis stenocarpa) Protein Hydrolysate Fractions  

Digital Repository Infrastructure Vision for European Research (DRIVER)

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 ...

Ajibola, Comfort F.; Fagbemi, Tayo N.; Fashakin, Joseph B.; Aluko, Rotimi E.

2011-01-01

337

Evaluation of nutrient supplementation to charcoal-treated and untreated rice straw hydrolysate for xylitol production by Candida guilliermondii  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Xylitol was produced by Candida guilliermondii from charcoal-treated and untreated rice straw hemicellulosic hydrolysate with or without nutrients (ammonium sulphate, calcium chloride, rice bran extract). Both, xylitol yield and volumetric productivity decreased significantly when the nutrients were added to treated and untreated hydrolysates. In the treated hydrolysate, the efficiency of xylose conversion to xylitol was 79% when the nutrients were omitted. The results demonstrated that rice ...

Solange Inês Mussatto; Inês Conceição Roberto

2005-01-01

338

Comparative environmental performance of lignocellulosic ethanol from different feedstocks  

International Nuclear Information System (INIS)

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 re 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)

339

Effect of Nitrogen Source Concentration on Curdlan Production by Agrobacterium sp. ATCC 31749 Grown on Prairie Cordgrass Hydrolysates.  

Science.gov (United States)

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 (2.2 mM) or a medium containing a complete hydrolysate and 3.3 mM ammonium phosphate. The latter medium sustained a higher level of bacterial curdlan production than the former medium after 144 h. Biomass production by ATCC 31749 was highest after 144 h when grown on a medium containing a solids-only hydrolysate and 2.2 or 8.7 mM ammonium phosphate. On the medium containing the complete hydrolysate, biomass production by ATCC 31749 was highest after 144 h when 3.3 mM ammonium phosphate was present. Bacterial biomass production after 144 h was greater on the complete hydrolysate medium compared to the solids-only hydrolysate medium. Curdlan yield produced by ATCC 31749 after 144 h from the complete hydrolysate medium containing 3.3 mM ammonium phosphate was higher than from the solids-only hydrolysate medium containing 2.2 mM ammonium phosphate. PMID:25397813

West, Thomas P

2014-11-14

340

Biostimulant action of a plant-derived protein hydrolysate produced through enzymatic hydrolysis  

Science.gov (United States)

The aim of this study was to evaluate the biostimulant action (hormone like activity, nitrogen uptake, and growth stimulation) of a plant-derived protein hydrolysate by means of two laboratory bioassays: a corn (Zea mays L.) coleoptile elongation rate test (Experiment 1), a rooting test on tomato cuttings (Experiment 2); and two greenhouse experiments: a dwarf pea (Pisum sativum L.) growth test (Experiment 3), and a tomato (Solanum lycopersicum L.) nitrogen uptake trial (Experiment 4). Protein hydrolysate treatments of corn caused an increase in coleoptile elongation rate when compared to the control, in a dose-dependent fashion, with no significant differences between the concentrations 0.75, 1.5, and 3.0 ml/L, and inodole-3-acetic acid treatment. The auxin-like effect of the protein hydrolysate on corn has been also observed in the rooting experiment of tomato cuttings. The shoot, root dry weight, root length, and root area were significantly higher by 21, 35, 24, and 26%, respectively, in tomato treated plants with the protein hydrolysate at 6 ml/L than untreated plants. In Experiment 3, the application of the protein hydrolysate at all doses (0.375, 0.75, 1.5, and 3.0 ml/L) significantly increased the shoot length of the gibberellin-deficient dwarf pea plants by an average value of 33% in comparison with the control treatment. Increasing the concentration of the protein hydrolysate from 0 to 10 ml/L increased the total dry biomass, SPAD index, and leaf nitrogen content by 20.5, 15, and 21.5%, respectively. Thus the application of plant-derived protein hydrolysate containing amino acids and small peptides elicited a hormone-like activity, enhanced nitrogen uptake and consequently crop performances. PMID:25250039

Colla, Giuseppe; Rouphael, Youssef; Canaguier, Renaud; Svecova, Eva; Cardarelli, Mariateresa

2014-01-01

 
 
 
 
341

Efficient degradation of lignocellulosic plant biomass without pretreatment by the 9 thermophilic anaerobe, Anaerocellum thermophilum DSM 6725  

Energy Technology Data Exchange (ETDEWEB)

Very few cultivated microorganisms can degrade lignocellulosic biomass without chemical pretreatment. We show here that 'Anaerocellum thermophilum' DSM 6725, an anaerobic bacterium that grows optimally at 75 C, efficiently utilizes various types of untreated plant biomass, as well as crystalline cellulose and xylan. These include hardwoods such as poplar, low-lignin grasses such as napier and Bermuda grasses, and high-lignin grasses such as switchgrass. The organism did not utilize only the soluble fraction of the untreated biomass, since insoluble plant biomass (as well as cellulose and xylan) obtained after washing at 75 C for 18 h also served as a growth substrate. The predominant end products from all growth substrates were hydrogen, acetate, and lactate. Glucose and cellobiose (on crystalline cellulose) and xylose and xylobiose (on xylan) also accumulated in the growth media during growth on the defined substrates but not during growth on the plant biomass. A. thermophilum DSM 6725 grew well on first- and second-spent biomass derived from poplar and switchgrass, where spent biomass is defined as the insoluble growth substrate recovered after the organism has reached late stationary phase. No evidence was found for the direct attachment of A. thermophilum DSM 6725 to the plant biomass. This organism differs from the closely related strain A. thermophilum Z-1320 in its ability to grow on xylose and pectin. Caldicellulosiruptor saccharolyticus DSM 8903 (optimum growth temperature, 70 C), a close relative of A. thermophilum DSM 6725, grew well on switchgrass but not on poplar, indicating a significant difference in the biomass-degrading abilities of these two otherwise very similar organisms.

Yang, Sung-Jae [University of Georgia, Athens, GA; Kataeva, Irina [University of Georgia, Athens, GA; Hamilton-Brehm, Scott [ORNL; Engle, Nancy L [ORNL; Tschaplinski, Timothy J [ORNL; Doeppke, Crissa [National Renewable Energy Laboratory (NREL); Davis, Dr. Mark F. [National Renewable Energy Laboratory (NREL); Westpheling, Janet [University of Georgia, Athens, GA; Adams, Michael W. W. [University of Georgia, Athens, GA

2009-01-01

342

Intermodal transportation of spent fuel  

Energy Technology Data Exchange (ETDEWEB)

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.

Elder, H.K.

1983-09-01

343

Intermodal transportation of spent fuel  

International Nuclear Information System (INIS)

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

344

IAEA spent fuel storage glossary  

International Nuclear Information System (INIS)

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

345

Fast reactor spent fuel processing  

International Nuclear Information System (INIS)

The characteristics of fast reactor fuel and of the fuel cycle and specific problems of fast reactor fuel reprocessing are discussed. Wet and dry methods of spent fuel reprocessing are described and the two methods are compared. Reprocessing efforts in France, FRG, Great Britain, USSR, Italy, Japan, and Belgium are reviewed. The problem is briefly outlined of proliferation associated with spent fuel reprocessing. (J.P.)

346

IAEA spent fuel storage glossary  

International Nuclear Information System (INIS)

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

347

Transportation of spent MTR fuels  

Energy Technology Data Exchange (ETDEWEB)

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.

Raisonnier, D.

1997-08-01

348

Enzymatic hydrolysis and ethanol fermentation of lignocellulosic materials  

Energy Technology Data Exchange (ETDEWEB)

The kinetics of enzymatic hydrolysis of different lignocellulosic materials (wheat straw, newspaper and microcrystalline cellulose Avicel PH 101) was studied using the cellulase complexes from Trichoderma reesei QM 9414 and its mutants M 5, M 6, MHC 15 and MHC 22. The maximum yields of hydrolysis were obtained with wheat straw partially delignified with 1% NaOH as substrate, and using the enzyme from the mutants T. reesei M 6 and MHC 22. The possibility of simultaneous enzymatic hydrolysis and ethanol fermentation of wheat straw using the enzyme complex from M6 and yeasts of the genus Candida and Torulopsis was also investigated. A good conversion of liberated glucose and cellobiose to ethanol was obtained, however, xylose was not fermented. (Refs. 21).

Danielova, E.; Farkas, V.; Bauer, S.

1983-01-01

349

Utilization of Lignocellulosic Waste for the Preparation of Nitrogenous Biofertilizer  

Directory of Open Access Journals (Sweden)

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.

Farhat R. Malik

2001-01-01

350

Epidemic based modeling of enzymatic hydrolysis of lignocellulosic biomass.  

Science.gov (United States)

An epidemic based model was developed to describe the enzymatic hydrolysis of a lignocellulosic biomass, dilute sulfuric acid pretreated corn stover. The process of substrate getting adsorbed and digested by enzyme was simulated as susceptibles getting infected by viruses and becoming removed and recovered. This model simplified the dynamic enzyme "infection" process and the catalysis of cellulose into a two-parameter controlled, enzyme behavior guided mechanism. Furthermore, the model incorporates the adsorption block by lignin and inhibition effects on cellulose catalysis. The model satisfactorily predicted the enzyme adsorption and hydrolysis, negative role of lignin, and inhibition effects over hydrolysis for a broad range of substrate and enzyme loadings. Sensitivity analysis was performed to evaluate the incorporation of lignin and other inhibition effects. Our model will be a useful tool for evaluating the effects of parameters during hydrolysis and guide a design strategy for continuous hydrolysis and the associated process control. PMID:25079785

Tai, Chao; Arellano, Maria G; Keshwani, Deepak R

2014-01-01

351

TPS/LDPE blends reinforced with lignocellulose fibers  

International Nuclear Information System (INIS)

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)

352

Lab-scale Technology for Biogas Production from Lignocellulose Wastes  

Directory of Open Access Journals (Sweden)

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.

Lukáš Krátký

2012-01-01

353

Effect of microaerobic fermentation in preprocessing fibrous lignocellulosic materials.  

Science.gov (United States)

Amending soil with organic matter is common in agricultural and logging practices. Such amendments have benefits to soil fertility and crop yields. These benefits may be increased if material is preprocessed before introduction into soil. We analyzed the efficiency of microaerobic fermentation (MF), also referred to as Bokashi, in preprocessing fibrous lignocellulosic (FLC) organic materials using varying produce amendments and leachate treatments. Adding produce amendments increased leachate production and fermentation rates and decreased the biological oxygen demand of the leachate. Continuously draining leachate without returning it to the fermentors led to acidification and decreased concentrations of polysaccharides (PS) in leachates. PS fragmentation and the production of soluble metabolites and gases stabilized in fermentors in about 2-4 weeks. About 2 % of the carbon content was lost as CO(2). PS degradation rates, upon introduction of processed materials into soil, were similar to unfermented FLC. Our results indicate that MF is insufficient for adequate preprocessing of FLC material. PMID:22639359

Alattar, Manar Arica; Green, Terrence R; Henry, Jordan; Gulca, Vitalie; Tizazu, Mikias; Bergstrom, Robby; Popa, Radu

2012-06-01

354

Development of a commercial enzymes system for lignocellulosic biomass saccharification  

Energy Technology Data Exchange (ETDEWEB)

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.

Kumar, Manoj

2012-12-20

355

Studies on the adsorption of cellulase on lignocellulosics  

Energy Technology Data Exchange (ETDEWEB)

Adsorption characteristics of different activities in a crude cellulase solution derived from Trichoderma reesei D1 to 6 on lignocellulosic materials such as rice straw and bagasse were studied and compared with the adsorption on micro-crystalline cellulose powder and Solka Floc. The effect of particle size reduction, temperature and enzyme concentration on the adsorption of cellulase were also studied. The three activities of the enzyme against filter paper, carboxymethyl cellulose and p-nitrophenyl-..beta..-D-glucoside were all adsorbed on the cellulose surface. Crystallinity index and the amount of enzyme adsorbed showed no correlation. Varying particle size and temperature had only a limited effect on the adsorption of these enzyme activities. A Langmuir adsorption isotherm type equation satisfactorily related the adsorbed enzyme activity to the free enzyme activity in a mixture.

Goel, S.C.; Ramachandran, K.B.

1983-01-01

356

Experimental modelling of a pilot lignocellulosic pellets stove plant  

International Nuclear Information System (INIS)

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)

357

Ultrasound-assisted fractionation of the lignocellulosic material.  

Science.gov (United States)

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

García, Araceli; Alriols, María González; Llano-Ponte, Rodrigo; Labidi, Jalel

2011-05-01

358

Bioethanol from Lignocellulosic Biomass: Current Findings Determine Research Priorities  

Science.gov (United States)

“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

Kang, Qian; Appels, Lise; Tan, Tianwei

2014-01-01

359

Fuel lignocellulosic briquettes, die design and products study  

Energy Technology Data Exchange (ETDEWEB)

Briquetting of biomass can be done through various techniques. The present work describes the process of designing a taper die and its optimisation for use in a hydraulic machine. The application of an experimental design technique, and the later statistical analysis of the results is presented, applied to a laboratory hydraulic press densification process of lignocellulosic biomass. The most appropriate experiment type is determined for a first set of experiments; calculating, among other things: minimum number of tests to carry out to obtain binding conclusions, most influential factors, and search paths to improve fuel quality. Another experiment type is determined for a second set of experiments, taking account of the most influential factors (pressure, temperature and moisture content), and also the number of tests to carry out considering the improvement of density and friability. Finally, an approximation study of the best product allows conclusions to be reached on product behaviour beyond the experimental design range factors. (Author)

Granada, E.; Miguez, J.L.; Moran, J. [Vigo Univ. (Spain). E.T.S. Ingenieros Industriales y Minas; Lopez Gonzalez, L.M. [Universidad de La Rioja (Spain). Departamento de Ingenieria Mecanica

2002-12-01

360

Spent Nuclear Fuel project, project management plan  

Energy Technology Data Exchange (ETDEWEB)

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

Fuquay, B.J.

1995-10-25

 
 
 
 
361

Spent Nuclear Fuel project, project management plan  

International Nuclear Information System (INIS)

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

362

Chemical and radiation-chemical radical reactions in lignocellulose materials  

International Nuclear Information System (INIS)

Chemical and radiation-chemical radical reactions in lignocellulose materials were explored by 3-cm and 2-mm ESR spectroscopy. Background (intrinsic) singlet signals at g=2.003 from wood pulp and lignin and those arising during reaction of lignocellulose materials with acids and chlorine were attributed to radicals with conjugated C--C bonds. The 2-mm ESR signal with 3D anisotropy of g-factor from o-semiquinone radical ions formed in reaction of lignin with NaOH was recorded for the first time. The singlet signals derived from cellulose ?-irradiated at 77 K and marked out during post-thermal reactions were assigned to radicals with conjugated bonds. In wetted cellulose, a triplet signal with ??H?2.7 mT and imposed quadruplet structure (0.5-0.7 mT) from three ?-protons was detected at 300 K and attributed to S4-radicals. The triplet signals derived from S2- and S3-radicals in pyranose cycles of cellulose exhibited higher values of ??H (3.0-3.2 mT) and lower thermal stability (up to 250 K). In radiolyzed cotton pulp, detected were ESR signals derived from formyl radicals formed upon rupture of the S5--S6 bond in pyranose cycles. Heating up irradiated samples under O2 was accompanied by formation of peroxide radicals. Photoinduced recombination of trapped electrons with S1-radicals was found to proceed as a chain reaction with a kinetic length in reaction with a kinetic length of about 25 units. Photolysis (??360 nm) of radiolyzed cellulose enhanced the disclosure of pyranose cycles and, as a result, the evolution of CO2 by a factor of 2-2.5.

363

HFIR spent fuel management alternatives  

International Nuclear Information System (INIS)

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

364

HFIR spent fuel management alternatives  

Energy Technology Data Exchange (ETDEWEB)

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.

Begovich, J.M.; Green, V.M.; Shappert, L.B.; Lotts, A.L.

1992-10-15

365

HFIR spent fuel management alternatives  

Energy Technology Data Exchange (ETDEWEB)

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.

Begovich, J.M.; Green, V.M.; Shappert, L.B.; Lotts, A.L.

1992-10-15

366

Thermogravimetric-mass spectrometric analysis of lignocellulosic and marine biomass pyrolysis.  

Science.gov (United States)

The pyrolysis characteristics of three lignocellulosic biomasses (fir wood, eucalyptus and pine bark) and a marine biomass (Nannochloropsis gaditana microalgae) were investigated by thermogravimetric analysis coupled with mass spectrometry (TGA-MS). Thermal degradation of lignocellulosic biomass was divided into four zones, corresponding to the decomposition of their main components (cellulose, hemicellulose and lignin) and a first step associated to water removal. Differences in volatile matter and cellulose content of lignocellulosic species resulted in different degradation rates. Microalgae pyrolysis occurred in three stages due to the main components of them (proteins), which are greatly different from lignocellulosic biomass. Heating rate effect was also studied. The main gaseous products formed were CO(2), light hydrocarbons and H(2)O. H(2) was detected at high temperatures, being associated to secondary reactions (char self-gasification). Pyrolysis kinetics were studied using a multiple-step model. The proposed model successfully predicted the pyrolytic behaviour of these samples resulting to be statistically meaningful. PMID:22297048

Sanchez-Silva, L; López-González, D; Villaseñor, J; Sánchez, P; Valverde, J L

2012-04-01

367

Enzyme Characterization of Cellulase and Hemicellulases Component Enzymes and Saccharification of Ionic Liquid Pretreated Lignocellulosic Biomass  

Science.gov (United States)

Lignocellulosic biomass is comprised of cellulose and hemicellulose, sources of polysaccharides, and lignin, a macromolecule with extensive aromaticity. Terrestrial biomass can provide a renewable carbon based feedstock for fuel and chemical production. However, recalcitrance of biomass to deconstru...

368

Environmentally-friendly sonochemistry synthesis of hybrids from lignocelluloses and silver.  

Science.gov (United States)

The purpose of this study was to explore a green strategy about the high value-added applications of biomass. Hybrids from lignocelluloses and silver have been successfully prepared using NaBH4 as reducing reagent by an environmentally-friendly sonochemistry method. The phase, microstructure, and morphology of the hybrids were characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM), thermogravimetric analysis (TGA), and differential thermal analysis (DTA). The influences of the various reaction parameters including reaction time, lignocelluloses concentration, and types of reducing reagents on the products were investigated in detail. Silver particles can be better dispersed on the lignocelluloses matrix by adjusting reaction parameters. These hybrids may be a promising antimicrobial material for their applications in the biomedical field. This environmentally-friendly synthetic strategy reported here opens a new window to the high value-added applications of lignocelluloses. PMID:24507304

Dong, Yan-Yan; Li, Shu-Ming; Ma, Ming-Guo; Zhao, Jin-Jin; Sun, Run-Cang; Wang, Shan-Peng

2014-02-15

369

Genomic mechanisms of inhibitor-detoxification for low-cost lignocellulosic bioethanol conversion  

Science.gov (United States)

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...

370

Towards an Understanding of How Protein Hydrolysates Stimulate More Efficient Biosynthesis in Cultured Cells  

Science.gov (United States)

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.

Siemensma, André; Babcock, James; Wilcox, Chris; Huttinga, Hans

371

Toxic effects of dietary hydrolysed lipids: an in vivo study on fish larvae.  

Science.gov (United States)

We have previously described that fish larvae absorb a larger fraction of dietary monoacylglycerol than TAG. To investigate how dietary hydrolysed lipids affect a vertebrate at early life stages over time, we fed Atlantic cod (Gadus morhua) larvae six diets with different degrees of hydrolysed lipids for 30 d. The different diets had no effect on growth, but there was a positive correlation between the level of hydrolysed lipids in the diets and mortality. Important genes in lipid metabolism, such as PPAR, farnesoid X receptor (FXR) and stearoyl-CoA desaturase (SCD), were regulated by the different diets. Genes involved in the oxidative stress response did not respond to the increased lipid hydrolysation in the diets. However, enterocyte damage was observed in animals fed diets with 2.7 % NEFA (diet 3) or more. It is thus possible that mortality was due to infections and/or osmotic stress due to the exposure of the subepithelial tissue. In contrast to earlier experiments showing a positive effect of dietary hydrolysed lipids, we have demonstrated a toxic effect of dietary NEFA on Atlantic cod larvae. Toxicity is not acute but needs time to accumulate. PMID:22813630

Sæle, Øystein; Nordgreen, Andreas; Olsvik, Pål A; Hjelle, Jan I; Harboe, Torstein; Hamre, Kristin

2013-03-28

372

Development of an enzymatic fish hydrolysate and its use in instant soup bases.  

Science.gov (United States)

The successful conservation of fish products, at low costs, is a subject of special interest in the developing countries. Conscious of this fact, our group has been studying several fish conservation methods, such as autolysis with high salt concentrations, and has obtained a sauce of high nutritive value and long shelf life. Nevertheless, the reaction process takes from four to six months. In the study herein reported, the hydrolysis was accelerated and controlled by using the following enzymes: papain, HT proteolytic, and Brew (N) zyme. The hydrolysate was then mixed with cereals to prepare instant soups. As results indicated, the best hydrolysate was obtained with Brew (N) zyme at 50 degrees C and 8.30 hours. This hydrolysate contains 93.0 g/100 g crude protein with a protein efficiency ratio (PER) and a net protein utilization (NPU) of 60% that of casein's NPU as well as a content of 0.8% ether extract. The lowest-cost mixtures with the highest nutritive value were: hydrolysate-wheat-soymeal, and hydrolysate-rice-soymeal, with 38.3 and 29.7 protein per 100 g of mixture, respectively, and a NPU of 79.0 and 79.8% in relation to casein, respectively. The soups prepared had a satisfactory acceptance rating. There were no significant differences in flavor and aroma at a confidence level of 95%. The cost per gram of protein is about US$ 0.22 per kg. PMID:3842931

Gálvez, A; Morales de Léon, J; Bourges Rodríguez, H

1985-12-01

373

Inhibition of Cellulase-Catalyzed Lignocellulosic Hydrolysis by Iron and Oxidative Metal Ions and Complexes ?  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Enzymatic lignocellulose hydrolysis plays a key role in microbially driven carbon cycling and energy conversion and holds promise for bio-based energy and chemical industries. Cellulases (key lignocellulose-active enzymes) are prone to interference from various noncellulosic substances (e.g., metal ions). During natural cellulolysis, these substances may arise from other microbial activities or abiotic events, and during industrial cellulolysis, they may be derived from biomass feedstocks or ...

Tejirian, Ani; Xu, Feng

2010-01-01

374

Ethanol production from lignocellulosic biomass by recombinant Escherichia coli strain FBR5  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Lignocellulosic biomass, upon pretreatment and enzymatic hydrolysis, generates a mixture of hexose and pentose sugars such as glucose, xylose, arabinose and galactose. While Escherichia coli utilizes all these sugars it lacks the ability to produce ethanol from them. Recombinant ethanologenic E. coli strains have been created with a goal to produce ethanol from both hexose and pentose sugars. Herein, we review the current state of the art on the production of ethanol from lignocellulosic hydr...

Saha, Badal; Cotta, Michael A.

2012-01-01

375

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

Bioethanol is nowadays one of the main actors in the fuel market. It is currently produced from sugars and starchy materials, but lignocelluloses can be expected to be major feedstocks for ethanol production in the future. Two processes are being developed in parallel for conversion of lignocelluloses to ethanol, “acid-based” and “enzyme-based” processes. The current article is dedicated to review of progress in the “acid-based-hydrolysis” process. This process was used industrial...

Keikhosro Karimi; Taherzadeh, Mohammad J.

2007-01-01

376

Design and construction of modular genetic devices and the enzymatic hydrolysis of lignocellulosic biomass  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The enzymatic deconstruction of lignocellulosic plant biomass is performed by specialist microbial species. It is a ubiquitous process within nature and central to the global recycling of carbon and energy. Lignocellulose is a complex heteropolymer, highly recalcitrant and resistant to hydrolysis due to the major polysaccharide cellulose existing as a crystalline lattice, intimately associated with a disordered sheath of hemicellulosic polysaccharides and lignin. In this thesis...

Barnard, Damian Kelly

2012-01-01

377

Relationship between Calorific Value and Elementary Composition of Torrefied Lignocellulosic Biomass  

Digital Repository Infrastructure Vision for European Research (DRIVER)

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...

Yusup, S.; Subbarao, D.; Tsutsui, T.; Omar, W.; Uemura, Y.

2010-01-01

378

Application of steam explosion for the pretreatment of the lignocellulosic raw materials  

Digital Repository Infrastructure Vision for European Research (DRIVER)

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...

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

2010-01-01

379

The Challenge of Efficient Synthesis of Biofuels from Lignocellulose for Future Renewable Transportation Fuels  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Dehydration of sugars to 5-hydroxymethylfurfural (HMF) has recently been under intensive study by a multitude of research groups. On the other hand, when lignocellulosic biomass is applied as the starting material, very few studies can be found in the open literature. The direct synthesis of HMF, in line with the idea of “one-pot” synthesis strategy from lignocellulose, is demanding since the overall process should encompass dissolution, hydrolysis, and dehydration steps in a single proce...

Amp Ki-arvela, P. Amp Ivi M.; Eero Salminen; Toni Riittonen; Pasi Virtanen; Narendra Kumar; Jyri-Pekka Mikkola

2012-01-01

380

Adaptation of a flocculent Saccharomyces cerevisiae strain to lignocellulosic inhibitors by cell recycle batch fermentation  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The ethanol production from lignocellulosic feedstocks is considered a promising strategy to increase global production of biofuels without impacting food supplies. However, some compounds released during the hydrolysis of lignocellulosic materials are toxic for the microbial metabolism, causing low ethanol yield and productivity during the fermentation. As an attempt to overcome this problem, the present study evaluated the adaptation of a flocculent strain of Saccharomyces cerevisiae (NRRL ...

Landaeta, R.; Aroca, G.; Acevedo, F.; Teixeira, J. A.; Mussatto, Solange I.

2013-01-01

 
 
 
 
381

Cellulolytic enzymes on lignocellulosic substrates in solid state fermentation by Aspergillus niger  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The production of cellulolytic enzymes by Aspergillus niger on lignocellulosic substrates groundnut fodder, wheat bran, rice bran and sawdust in solid state fermentation in a laboratory scale was compared. Czapek Dox liquid broth amended with cellulose (0.5%) was used to moisten lignocellulosic solid supports for cultivation of Aspergillus niger. The production of filter paperase, carboxymethyl cellulase and -glucosidase were monitored at daily intervals for 5 days. The peak production of the...

Chandra, M. Subhosh; Viswanath, Buddolla; Reddy, B. Rajasekhar

2007-01-01

382

Engineering xylose metabolism in triacylglycerol-producing Rhodococcus opacus for lignocellulosic fuel production  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Background: There has been a great deal of interest in fuel productions from lignocellulosic biomass to minimize the conflict between food and fuel use. The bioconversion of xylose, which is the second most abundant sugar present after glucose in lignocellulosic biomass, is important for the development of cost effective bioprocesses to fuels. Rhodococcus opacus PD630, an oleaginous bacterium, accumulates large amounts of triacylglycerols (TAGs), which can be processed into advanced liquid...

Kurosawa, Kazuhiko; Wewetzer, Sandra J.; Sinskey, Anthony J.

2013-01-01

383

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

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 ...

Keikhosro Karimi; Taherzadeh, Mohammad J.

2008-01-01

384

Cellulose, hemicelluloses, lignin, and ash contents in various lignocellulosic crops for second generation bioethanol production  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Cellulose, hemicelluloses, lignin, and ash contents in various lignocellulosic crops for second generation bioethanol production. Various green energy crops are available for the production of renewable energy vectors such as second generation bioethanol. The efficiency of the energy recovery potential of these lignocellulosic crops depends on the crop husbandry, their content of main components (cellulose, hemicelluloses, lignin, ash) and on the second generation bioethanol production proces...

Godin, Bruno; Ghysel, Francois; Agneessens, Richard; Schmit, Thomas; Gofflot, Sebastien; Lamaudiere, Ste?phane; Sinnaeve, Georges; Goffart, Jean-pierre; Gerin, Patrick A.; Stilmant, Didier; Delcarte, Jerome

2010-01-01

385

Development of spent fuel remote handling technology  

Energy Technology Data Exchange (ETDEWEB)

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

Yoon, Ji Sup; Park, B. S.; Park, Y. S.; Oh, S. C.; Kim, S. H.; Cho, M. W.; Hong, D. H

1997-12-01

386

Development of spent fuel remote handling technology  

International Nuclear Information System (INIS)

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

387

Utilization of anaerobically treated distillery spent wash for production of cellulases under solid-state fermentation.  

Science.gov (United States)

Pollution caused by distillery spent wash on one hand has stimulated the need to develop new technologies to treat the waste and on the other, forced us to reevaluate the efficient utilization of its nutritive potential for production of various high value compounds. In this study, anaerobically treated distillery spent wash was used for the production of cellulases by Aspergillus ellipticus under solid-state fermentation using wheat straw as a substrate. The interactions between distillery effluent concentration, initial pH, moisture content and inoculum size were investigated and modeled using response surface methodology (RSM) involving Box-Behnken design (BBD). Under optimized conditions, filter paper activity, beta-glucosidase and endo-beta-1,4-glucanase activities were found to be 13.38, 26.68 and 130.92 U/g of substrate respectively. Characterization of endo-beta-1,4-glucanase and beta-glucosidase was done after partial purification by ammonium sulfate fractionation followed by desalting. The partially purified endo-beta-1,4-glucanase and beta-glucosidase showed maximum activity at 60 degrees C. Saccharification studies performed with different lignocellulosic substrates showed that wheat bran was most susceptible to enzymatic hydrolysis. The study suggests that anaerobically treated distillery spent wash can be used as a viable nutrient source for cellulase production under solid-state fermentation by A. ellipticus. PMID:20627545

Acharya, Bhavik K; Mohana, Sarayu; Jog, Rahul; Divecha, Jyoti; Madamwar, Datta

2010-10-01

388

Single cell protein production by penicillium expansum incorporating of acid hydrolysate of rice husk in medium  

International Nuclear Information System (INIS)

The aim of the research work is to bioconversion of rice husk to single cell protein by penicillium expansum. The rice husk was degraded chemically using sulphuric acid and perchloric acid with various concentrations (0.15, 0.30, 0.45, and 0.60 N) to fermentable sugars and these were used as substrate for the production of single cell protein by penicillium expansum. It was observed that the amount of single cell protein is higher in case of perchloric acid hydrolysate in comparison to sulphuric acid hydrolysate, while the protein content of single cell protein is higher in sulphuric acid hydrolysate. The single cell protein of penicillium expansum contains nearly all essential amino acids while it free from aflatoxin. (author)

389

Mathematical modeling of hydrolysate diffusion and utilization in cellulolytic biofilms of the extreme thermophile Caldicellulosiruptor obsidiansis  

Energy Technology Data Exchange (ETDEWEB)

Abstract: The morphological and structural properties of microbial biofilms are influenced by internal substrate diffusion and utilization processes. In the case of microbial hydrolysis of plant cell walls, only thin and uniform biofilm structures are typically formed by cellulolytic microorganisms. In this study, we develop a hydrolysate diffusion and utilization model system to examine factors influencing cellulolytic biofilm formation. Model simulations using Caldicellulosiruptor obsidiansis as a representative organism, reveal that the growth of the cellulolytic biofilm is limited by hydrolysate utilization but not diffusion. As a consequence, the cellulolytic biofilm has a uniform growth rate, and there is a hydrolysate surplus that diffuses through the cellulolytic biofilm into the bulk solution where it is consumed by planktonic cells. Predictions based on the model were tested in a cellulose fermentation study and the results are consistent with the model and previously reported experimental data. The factors determining the rate-limiting step of biofilm growth are also analyzed.

Wang, Zhiwu [ORNL; Hamilton-Brehm, Scott [ORNL; Lochner, Adriane [ORNL; Elkins, James G [ORNL; Morrell-Falvey, Jennifer L [ORNL

2011-01-01

390

Acid-generated soy protein hydrolysates and their interfacial behavior on model surfaces.  

Science.gov (United States)

The present work attempts to provide data to warrant the consideration of soy proteins (SP) as potentially useful biomolecules for practical chemical and surface applications. Despite their sundry properties, SP use has been limited by their high molecular weight. In response to this limitation, we analyze acid hydrolysates of soy proteins (0.1 N HCl, 70 °C) for surface modification. Techniques typical in protein (SDS-PAGE) as well as colloidal (charge demand and electrophoretic mobility) analyses were used to follow the effects of molecular changes that occur upon hydrolysis. Adsorption experiments on hydrophobic (polypropylene) and mineral (aluminum oxide) surfaces were subsequently carried out to further interrogate the surface activity resultant from soy hydrolysis. It was found that during adsorption the hydrolysates tended to form less surface aggregates and adsorbed at faster rates compared with unmodified SP. Overall, the benefits derived from the application of SP hydrolysates are highlighted. PMID:25314296

Arboleda, Julio C; Rojas, Orlando J; Lucia, Lucian A

2014-11-10

391

Systematic Investigation of Antioxidant Activity of Egg White Protein Hydrolysates Obtained by Pepsin  

Directory of Open Access Journals (Sweden)

Full Text Available 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 activity (67.72±2.51% and inhibitory activity of tea oil autoxidation (62.68±2.32% compared to other EWPHs. At DH 18.22%, the EWPHs exhibited the strongest reducing power (0.34±0.014. The results revealed that antioxidative activity of protein hydrolysates from egg white was determined by the DH. According to the experimental results, the EWPHs have potential for use as a natural antioxidant for food preservation.

Shuguo Sun

2013-01-01

392

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

Directory of Open Access Journals (Sweden)

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.

Junping Zhuang

2009-05-01

393

Fish protein hydrolysates: proximate composition, amino acid composition, antioxidant activities and applications: a review.  

Science.gov (United States)

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

Chalamaiah, M; Dinesh Kumar, B; Hemalatha, R; Jyothirmayi, T

2012-12-15

394

Efficient Open Fermentative Production of Polymer-Grade L-Lactate from Sugarcane Bagasse Hydrolysate by Thermotolerant Bacillus sp. Strain P38  

Science.gov (United States)

Lactic acid is one of the top 30 potential building-block chemicals from biomass, of which the most extensive use is in the polymerization of lactic acid to poly-lactic-acid (PLA). To reduce the cost of PLA, the search for cheap raw materials and low-cost process for lactic acid production is highly desired. In this study, the final titer of produced L-lactic acid reached a concentration of 185 g·L?1 with a volumetric productivity of 1.93 g·L?1·h?1 by using sugarcane bagasse hydrolysate as the sole carbon source simultaneously with cottonseed meal as cheap nitrogen sources under the open fed-batch fermentation process. Furthermore, a lactic acid yield of 0.99 g per g of total reducing sugars was obtained, which is very close to the theoretical value (1.0 g g?1). No D-isomer of lactic acid was detected in the broth, and thereafter resulted in an optical purity of 100%, which exceeds the requirement of lactate polymerization process. To our knowledge, this is the best performance of fermentation on polymer-grade L-lactic acid production totally using lignocellulosic sources. The high levels of optically pure l-lactic acid produced, combined with the ease of handling and low costs associated with the open fermentation strategy, indicated the thermotolerant Bacillus sp. P38 could be an excellent candidate strain with great industrial potential for polymer-grade L-lactic acid production from various cellulosic biomasses. PMID:25192451

Guo, Ling; Wang, Limin; Yu, Bo; Ma, Yanhe

2014-01-01

395

Antioxidant Activity of Fish Protein Hydrolysates in in vitro Assays and in Oil-in-Water Emulsions.  

DEFF Research Database (Denmark)

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

Farvin, Sabeena; Andersen, Lisa Lystbæk

396

Sensory analysis of hydrolysed meat preparations Análise sensorial de preparações com hidrolisados de carne  

Directory of Open Access Journals (Sweden)

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 utilização de hidrolisados de carne em dietas melhora seu conteúdo protéico, de vitaminas e minerais. O objetivo do presente trabalho foi avaliar a aceitação de hidrolisados de carne. Quatro preparações foram desenvolvidas com três tipos de hidrolisados em condições similares às domésticas. . A aceitação foi avaliada com uso de escala hedônica de 9 pontos. Os testes foram realizados em três sessões (de acordo com o tipo de hidrolisado e, incluiu-se na ficha de avaliação informações de idade. A análise estatística foi realizada por ANOVA e teste de Tukey. As preparações mais aceitas foram os bolinhos com hidrolisados de peru e frango. Os hidrolisados podem ser utilizados em diversas preparações, sendo necessário o conhecimento da faixa etária a qual se destinam, suas características sensoriais e físico-químicas, para garantir o sabor e a aparência do produto final.

Maria Elisabeth Machado Pinto E Silva

2010-06-01

397

Sensory analysis of hydrolysed meat preparations / Análise sensorial de preparações com hidrolisados de carne  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in portuguese A utilização de hidrolisados de carne em dietas melhora seu conteúdo protéico, de vitaminas e minerais. O objetivo do presente trabalho foi avaliar a aceitação de hidrolisados de carne. Quatro preparações foram desenvolvidas com três tipos de hidrolisados em condições similares às domésticas. . A ac [...] eitação foi avaliada com uso de escala hedônica de 9 pontos. Os testes foram realizados em três sessões (de acordo com o tipo de hidrolisado) e, incluiu-se na ficha de avaliação informações de idade. A análise estatística foi realizada por ANOVA e teste de Tukey. As preparações mais aceitas foram os bolinhos com hidrolisados de peru e frango. Os hidrolisados podem ser utilizados em diversas preparações, sendo necessário o conhecimento da faixa etária a qual se destinam, suas características sensoriais e físico-químicas, para garantir o sabor e a aparência do produto final. Abstract in english 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 verifi [...] ed 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.

Maria Elisabeth Machado Pinto E, Silva; Maria Carolina von, Atzingen.

2010-06-01

398

Intermodal transfer of spent fuel  

Energy Technology Data Exchange (ETDEWEB)

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.

Neuhauser, K. S. [Sandia National Labs., Albuquerque, NM (United States); Weiner, R. F. [Western Washington Univ., Bellingham, WA (United States)

1991-01-01

399

The protein encoded by the rolB plant oncogene hydrolyses indole glucosides.  

Digital Repository Infrastructure Vision for European Research (DRIVER)

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...

Estruch, J. J.; Schell, J.; Spena, A.

1991-01-01

400

In Vitro Antioxidant Activities of Protein Hydrolysate from Germinated Black Soybean (Glycine max L.  

Directory of Open Access Journals (Sweden)

Full Text Available During this study, the effect of germination in combination with in vitro pepsin and pancreatin digestion of protein flours extracted from black soybean on the production of bioactive peptides was investigated. Black soybean (Glycine max L. were germinated for 3 days (at 24, 48 and 72 h, respectively germination periods and harvested. Protein hydrolysates from germinated black soybean were prepared from protein isolate by in vitro digestion using pepsin and pancreatin and then evaluated for antioxidant activity. Soy protein hydrolysate from 48 h of germination exhibited the highest scavenging activity against 2, 2-Diphenyl-1-Picrylhydrazyl (DPPH free radicals (76.56 % at 2.5 mg/mL followed by 24 and 72 h (66.62 and 60.55% at 2.5 mg/mL, respectively. Protein hydrolysate from germinated black soybean also exhibited noticeable scavenging activity for hydroxyl. Soy protein hydrolysate from 48 h of germination (97.475% at 2 mg/mL significantly was the most effective in neutralizing •OH (p<0.05 than that from 24 and 72 h (88.56 and 92.5%, respectively at 2 mg/mL, compared to the nongerminated which was 34.42% also at the same concentration. In addition, soyprotein hydrolysate from 24 h of germination significantly showed the highest reducing power (0.32 at 2.0 mg/mL compared to that from 48 and 72 h germination period (0.25 and 0.23 at 2.0 mg/mL, respectively. Molecular Weights distribution of protein hydrolysates from germinated black soybean was believed to have correlation with their antioxidant activities. Results showed that germination with in vitro digestion (pepsin and pancreatin of protein hydrolysate from germinated black soybean was successful in production of natural antioxidant compounds which established obvious antioxidant potency than non-germinated. As conclusion, soy protein hydrolysate from 48 h of germination had the best antioxidant potency and could be used as natural antioxidant in food systems.

Ralison Solominoarisoa Sefatie

2013-04-01

 
 
 
 
401

Oil Production from Yarrowia lipolytica Po1g Using Rice Bran Hydrolysate  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The purpose of this study was to produce microbial oil from Yarrowia lipolytica Po1g grown in defatted rice bran hydrolysate. After removing oil from rice bran by Soxhlet extraction, the bran is subjected to acid hydrolysis with various sulfuric acid concentrations (1–4% v/v), reaction times (1–8?h), and reaction temperatures (60–120°C). The optimal conditions for maximum total sugar production from the hydrolysate were found to be 3% sulfuric acid at 90°C for 6?h. Glucose was the...

Yeshitila Asteraye Tsigie; Chun-Yuan Wang; Kasim, Novy S.; Quy-Do Diem; Lien-Huong Huynh; Quoc-Phong Ho; Chi-Thanh Truong; Yi-Hsu Ju

2012-01-01

402

Rapid determination of furfural in biomass hydrolysate by full evaporation headspace gas chromatography.  

Science.gov (United States)

This paper reports a full evaporation (FE) headspace gas chromatographic (HS-GC) method for rapid determination of furfural in the biomass hydrolysate. The data show that a near-complete mass transfer of furfural in the sample from biomass hydrolysate to the vapor phase (headspace) was achieved within 3 min at 105°C when a very small (headspace sample vial. The acid-catalyzed furfural decomposition under these conditions was negligible. The furfural in the vapor phase was then determined by HS-GC using a flame ionization detector. The results showed that the method has an excellent measurement precision (RSDethanol or other high value-added products. PMID:20970806

Li, Hailong; Chai, Xin-Sheng; Zhan, Huaiyu; Fu, Shiyu

2010-11-26

403

Improvement of biotechnological xylitol production by glucose during cultive of Candida guilliermondii in sugarcane bagasse hydrolysate  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The effect of glucose on xylose-to-xylitol bioconversion by Candida guilliermondii was examined by adding it to sugarcane bagasse hydrolysate medium to obtain different glucose:xylose ratios (1:25, 1:12, 1:5 and 1:2.5). Under experimental conditions, increasing glucose:xylose ratio improved the assimilation of the xylose present in the hydrolysate by yeast, resulting in biomass increase, and in the formation of xylitol and glycerol/ethanol by-products. Maximum values of xylitol yield (0.59 g ...

Débora Danielle Virgínio da Silva; Ismael Maciel de Mancilha; Silvio Silvério da Silva; Maria das Graças de Almeida Felipe

2007-01-01

404

Production of bioactive peptide hydrolysates from deer, sheep and pig plasma using plant and fungal protease preparations.  

Science.gov (United States)

Plasma separated from deer, sheep and pig blood, obtained from abattoirs, was hydrolysed using protease preparations from plant (papain and bromelain) and fungal (FP400 and FPII) sources. Antioxidant and antimicrobial activities of the peptide hydrolysates obtained after 1, 2, 4 and 24h of hydrolysis, were investigated. The release of trichloroacetic acid-soluble peptides over the hydrolysis period was monitored using the o-phthaldialdehyde (OPA) assay, while the hydrolysis profiles were visualised using SDS-PAGE. The major plasma proteins in the animal plasmas were identified using MALDI-TOF-TOF MS. Hydrolysates of plasma generated with fungal proteases exhibited higher DPPH radical-scavenging, oxygen radical-scavenging capacity (ORAC) and ferric reducing antioxidant power (FRAP) than those generated with plant proteases for all three animal plasmas. No antimicrobial activity was detected in the hydrolysates. The results indicated that proteolytic hydrolysis of animal blood plasmas, using fungal protease preparations in particular, produces hydrolysates with high antioxidant properties. PMID:25624206

Bah, Clara S F; Bekhit, Alaa El-Din A; Carne, Alan; McConnell, Michelle A

2015-06-01

405

Reprocessing method for spent fuel  

International Nuclear Information System (INIS)

In a method of reprocessing spent fuels by conducting anodic dissolution of spent oxide fuels and recovering uranium, plutonium and neptunium on a cathode, spent fuels are mixed with those of small electric resistance and an oxygen getter and charged in a vessel, and electrolysis is conducted while rotating the vessel by a motor to conduct anodic dissolution. With such procedures, areas of electrical contact are enlarged to improve the anodic dissolution rate. Molten salts are dissolved without precipitates of uranium oxides formed by the reaction of oxidized ions generated when FP oxides are dissolved or oxygen with ions of dissolved uranium oxides, to improve the processing rate. In addition, since electrolysis is conducted while rotating the cathode, precipitates are deposited uniformly on the cathode. Accordingly, substantial electrode are is enlarged to increase the amount of the precipitates to be recovered. Reprocessing can be conducted by a simple process, and minor actinides can be recovered together with U and Pu. (T.M.)

406

Decladding method of spent fuel  

International Nuclear Information System (INIS)

The present invention is used for a decladding step in a reprocessing step for spent nuclear fuels. Namely, notches are formed to a spent nuclear fuel rod containing fuel pellets in a cladding tube. Then, if load is applied thereto, the fuel rods are cut easily and reliably at the notched portions. The cut fuel rods are heated at an air atmosphere at from 500degC to 600degC. Then, fuel pellets in the fuel rod are oxidized to cause expansion of the volume. As a result, fuel pellets and the cladding tube can be separated reliably. Heretofore, spent fuels have been finely sheared, and the fuel pellets have been melted and extracted, but this method involves a drawback that the shearing blades are vigorously exhausted, and the waste shearing blades form radioactive wastes. In the present invention, the exhaustion of tools and wastes to be generated can be reduced. (I.S.)

407

Funcionalidade de hidrolisados proteicos de cabrinha (Prionotus punctatus) obtidos a partir de diferentes proteases microbianas Functionality of bluewing searobin (Prionotus punctatus) protein hydrolysates obtained from different microbial proteases  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The objective of this work was to study the influence of enzymes Alcalase, Flavourzyme and Novozym in the functional properties of hydrolysates of Bluewing searobin (Prionotus punctatus) minced. The hydrolysates of Bluewing searobin were evaluated for the chemical composition and the functional properties. The Novozym enzyme presented greater specific activity differing significantly from the enzymes Alcalase and Flavourzyme. The hydrolysates of Bluewing searobin pres...

Elessandra da Rosa Zavareze; Carolina Moroni Silva; Myriam Salas-Mellado; Carlos Prentice-Hernández

2009-01-01

408

Management of HFIR spent fuel  

International Nuclear Information System (INIS)

The High Flux Isotope Reactor (HFIR) at Oak Ridge National Laboratory (ORNL) has been unable to ship its spent fuel off-site for reprocessing since 1985. The HFIR storage pools are expected to fill up by the end of 1994. If a management alternative to existing HFIR pool storage is not identified and implemented by that time, the HFIR will be forced to shut down. This study identified and investigated five alternatives to managing the HFIR spent fuel, to determine the feasibility of implementing each in time to prevent shutdown of the HFIR: (1) increasing HFIR pool storage capacity, (2) storing the spent fuel at another ORNL pool, (3) storing the spent fuel in one or more hot cells at ORNL, (4) shipping the spent fuel off-site for reprocessing or storage elsewhere, and (5) installing a dedicated dry storage facility at ORNL. Of the alternatives investigated, only two could prevent the shutdown of the HFIR in the near term: increasing HFIR pool storage capacity or shipping the spent fuel off-site. Both options have been vigorously pursued because neither is assured of success, and at least one of the options must be successfully implemented if the HFIR is to continue operation. In addition, a third option was selected for implementation as an intermediate-term storage solution: installing a dedicated dry storage facility for the HFIR. An intermediate-term storage solution is needed because neither of the short-term solutions could ensure long-term continued operation ofld ensure long-term continued operation of the HFIR

409

Spent-fuel-storage alternatives  

Energy Technology Data Exchange (ETDEWEB)

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)

1980-01-01

410

Characterization of a microbial consortium capable of degrading lignocellulose.  

Science.gov (United States)

A microbial consortium, designated WCS-6, was established by successive subcultivation in the presence of rice straw under static conditions. The degradation efficiencies of WSC-6 for 0.5 g filter paper, cotton and rice straw after 3 days of cultivation were 99.0±0.7%, 76.9±1.5% and 81.3±0.8%, respectively as determined by gravimetrical methods. Nine bacterial isolates were obtained from WCS-6 plated under aerobic conditions, and sequencing of their 16S rDNA indicated that these bacteria were related to Bacillus thermoamylovorans BTa, Paenibacillus barengoltzii SAFN-016, Proteobacterium S072, Pseudoxanthomonas taiwanensis CB-226, Rhizobiaceae str. M100, Bacillus sp. E53-10, Beta proteobacterium HMD444, Petrobacter succinimandens 4BON, and Tepidiphilus margaritifer N2-214. DGGE (denaturing gradient gel electrophoresis) and sequencing of 16S rDNA sequences amplified from total consortium DNA revealed the presence of sequences related to those of Ureibacillus thermosphaericus, uncultured bacterium clone GC3, uncultured Clostridium sp. clone A1-3, Clostridium thermobutyricum, and Clostridium thermosuccinogenes in addition to the sequences identified from the cultured bacteria. The microbial community identified herein is a potential candidate consortium for the degradation of waste lignocellulosic biomass. PMID:21831630

Wang, Weidong; Yan, Lei; Cui, Zongjun; Gao, Yamei; Wang, Yanjie; Jing, Ruiyong

2011-10-01