Science.gov

Sample records for bioethanol process influence

  1. Diversity of lactic acid bacteria of the bioethanol process

    PubMed Central

    2010-01-01

    Background Bacteria may compete with yeast for nutrients during bioethanol production process, potentially causing economic losses. This is the first study aiming at the quantification and identification of Lactic Acid Bacteria (LAB) present in the bioethanol industrial processes in different distilleries of Brazil. Results A total of 489 LAB isolates were obtained from four distilleries in 2007 and 2008. The abundance of LAB in the fermentation tanks varied between 6.0 × 105 and 8.9 × 108 CFUs/mL. Crude sugar cane juice contained 7.4 × 107 to 6.0 × 108 LAB CFUs. Most of the LAB isolates belonged to the genus Lactobacillus according to rRNA operon enzyme restriction profiles. A variety of Lactobacillus species occurred throughout the bioethanol process, but the most frequently found species towards the end of the harvest season were L. fermentum and L. vini. The different rep-PCR patterns indicate the co-occurrence of distinct populations of the species L. fermentum and L. vini, suggesting a great intraspecific diversity. Representative isolates of both species had the ability to grow in medium containing up to 10% ethanol, suggesting selection of ethanol tolerant bacteria throughout the process. Conclusions This study served as a first survey of the LAB diversity in the bioethanol process in Brazil. The abundance and diversity of LAB suggest that they have a significant impact in the bioethanol process. PMID:21092306

  2. Process engineering economics of bioethanol production.

    PubMed

    Galbe, Mats; Sassner, Per; Wingren, Anders; Zacchi, Guido

    2007-01-01

    This work presents a review of studies on the process economics of ethanol production from lignocellulosic materials published since 1996. Our objective was to identify the most costly process steps and the impact of various parameters on the final production cost, e.g. plant capacity, raw material cost, and overall product yield, as well as process configuration. The variation in estimated ethanol production cost is considerable, ranging from about 0.13 to 0.81 US$ per liter ethanol. This can be explained to a large extent by actual process differences and variations in the assumptions underlying the techno-economic evaluations. The most important parameters for the economic outcome are the feedstock cost, which varied between 30 and 90 US$ per metric ton in the papers studied, and the plant capacity, which influences the capital cost. To reduce the ethanol production cost it is necessary to reach high ethanol yields, as well as a high ethanol concentration during fermentation, to be able to decrease the energy required for distillation and other downstream process steps. Improved pretreatment methods, enhanced enzymatic hydrolysis with cheaper and more effective enzymes, as well as improved fermentation systems present major research challenges if we are to make lignocellulose-based ethanol production competitive with sugar- and starch-based ethanol. Process integration, either internally or externally with other types of plants, e.g. heat and power plants, also offers a way of reducing the final ethanol production cost.

  3. EFFICIENT RECOVERY OF BIOETHANOL USING NOVEL PERVAPORATION-DEPHLEGMATION PROCESS

    EPA Science Inventory

    Bioethanol is the most important liquid fuel made in the U.S. from domestically produced renewable resources. Traditional production of bioethanol involves batch fermation of biomass followed by ethanol recovery from the fermentation broths using distillation. The distillation st...

  4. EFFICIENT RECOVERY OF BIOETHANOL USING NOVEL PERVAPORATION-DEPHLEGMATION PROCESS

    EPA Science Inventory

    Bioethanol is the most important liquid fuel made in the U.S. from domestically produced renewable resources. Traditional production of bioethanol involves batch fermation of biomass followed by ethanol recovery from the fermentation broths using distillation. The distillation st...

  5. Multistage process for the production of bioethanol from almond shell.

    PubMed

    Kacem, Imen; Koubaa, Mohamed; Maktouf, Sameh; Chaari, Fatma; Najar, Taha; Chaabouni, Moncef; Ettis, Nadia; Ellouz Chaabouni, Semia

    2016-07-01

    This work describes the feasibility of using almond shell as feedstock for bioethanol production. A pre-treatment step was carried out using 4% NaOH for 60min at 121°C followed by 1% sulfuric acid for 60min at 121°C. Enzymatic saccharification of the pre-treated almond shell was performed using Penicillium occitanis enzymes. The process was optimized using a hybrid design with four parameters including the incubation time, temperature, enzyme loads, and polyethylene glycol (PEG) concentration. The optimum hydrolysis conditions led to a sugar yield of 13.5%. A detoxification step of the enzymatic hydrolysate was carried out at pH 5 using 1U/ml of laccase enzyme produced by Polyporus ciliatus. Fermenting efficiency of the hydrolysates was greatly improved by laccase treatment, increasing the ethanol yield from 30% to 84%. These results demonstrated the efficiency of using almond shell as a promising source for bioethanol production. Copyright © 2016 Elsevier Ltd. All rights reserved.

  6. Process alternatives for bioethanol production from mango stem bark residues.

    PubMed

    Carrillo-Nieves, Danay; Ruiz, Héctor A; Aguilar, Cristóbal N; Ilyina, Anna; Parra-Saldivar, Roberto; Torres, J Antonio; Martínez Hernández, José L

    2017-09-01

    Three alternatives for bioethanol production from pretreated mango stem bark after maceration (MSBAM) were evaluated as a biorefinery component for the mango agroindustry. These included separate hydrolysis and fermentation (SHF), simultaneous saccharification and fermentation (SSF), and pre-saccharification followed by simultaneous saccharification and fermentation (PSSF). The effects on ethanol concentration, yield and productivity of pretreated MSBAM solids loading, Tween 20 addition, and temperature were used for process comparisons. The highest yields for the SHF, SSF, and PSSF process alternatives were 58.8, 81.6, and 84.5%, respectively. Since saccharification and fermentation are carried out in the same vessel in the SSF alternative, and no significant SSF and PSSF differences in ethanol concentration were observed, SSF is recommended as the best process configuration. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. Life cycle assessment of bioethanol production from woodchips with modifications in the pretreatment process.

    PubMed

    Shadbahr, Jalil; Zhang, Yan; Khan, Faisal

    2015-01-01

    Pretreatment as a crucial step in the process of ethanol production has significant influences on the process efficiency and on the environmental performance of the bioethanol production from lignocellulosic biomass. In present life cycle analysis (LCA) study, two cases for pretreatment of woodchips were considered as the focal point of the ethanol plant. One was assumed as base scenario whereas the second is the proposed alternative by implementation of modifications on the base design. In the first stage, LCA results of pretreatment unit showed lower environmental impacts in respiratory inorganics and land use than in new scenario, while the base scenario revealed better performance in fossil fuels. The results of the second stage of LCA study demonstrated improvement in proposed design in most categories of environmental impacts such as 18.5 % in land use as well as 17 % improvement in ecosystem quality.

  8. The influence of sorghum grain decortication on bioethanol production and quality of the distillers' dried grains with solubles using cold and conventional warm starch processing.

    PubMed

    Nkomba, Edouard Y; van Rensburg, Eugéne; Chimphango, Annie F A; Görgens, Johann F

    2016-03-01

    Very high gravity hydrolysis-fermentation of whole and decorticated sorghum grains were compared using conventional and cold hydrolysis methods to assess the extent by which decortication could minimize enzymes dosages and affect the quality of the distillers' dried grains with solubles (DDGS). All processing configurations achieved ethanol concentrations between 126 and 132 g/L (16.0-16.7%v/v), although decortication resulted in a decreased ethanol yield. Decortication resulted in a decreased volumetric productivity during warm processing from 1.55 to 1.25 g L(-1)h(-1), whereas the required enzyme dosage for cold processing was decreased from 250 to 221 μl/100 gstarch. Cold processing decreased the average acid detergent fibre (ADF) from 35.59% to 29.32% and neutral detergent fibre (NDF) from 44.04% to 32.28% in the DDGS compared to the conventional (warm) processing. Due to lower enzyme requirements, the use of decorticated grains combined with cold processing presents a favourable process configuration and source of DDGS for non-ruminants.

  9. Improvement of saccharification process for bioethanol production from Undaria sp. by gamma irradiation

    NASA Astrophysics Data System (ADS)

    Yoon, Minchul; Choi, Jong-il; Lee, Ju-Woon; Park, Don-Hee

    2012-08-01

    Recently, many research works have reported on improvements to the saccharification process that increase bioethanol production from cellulosic materials. Gamma irradiation has been studied as an effective method for the depolymerization of complex polysaccharides. In this study, the effect of gamma irradiation on saccharification of Undaria biomass for bioethanol production was investigated. The Undaria biomass was irradiated at doses of 0, 10, 50, 100, 200 and 500 kGy and then hydrolyzed using sulfuric acid. The effects of gamma irradiation were measured through microscopic analysis to determine morphological changes and concentration of the reducing sugar of hydrolysates. Microscopic images show that gamma irradiation causes structure breakage of the Undaria cell wall. The concentration of reducing sugar of hydrolysates significantly increased as a result of gamma irradiation, with or without acid hydrolysis. These results indicate that the combined method of gamma irradiation with acid hydrolysis can significantly improve the saccharification process for bioethanol production from marine algae materials.

  10. Process design and evaluation of production of bioethanol and β-lactam antibiotic from lignocellulosic biomass.

    PubMed

    Kim, Sung Bong; Park, Chulhwan; Kim, Seung Wook

    2014-11-01

    To design biorefinery processes producing bioethanol from lignocellulosic biomass with dilute acid pretreatment, biorefinery processes were simulated using the SuperPro Designer program. To improve the efficiency of biomass use and the economics of biorefinery, additional pretreatment processes were designed and evaluated, in which a combined process of dilute acid and aqueous ammonia pretreatments, and a process of waste media containing xylose were used, for the production of 7-aminocephalosporanic acid. Finally, the productivity and economics of the designed processes were compared.

  11. Techno-economic analysis of different pretreatment processes for lignocellulosic-based bioethanol production.

    PubMed

    da Silva, André Rodrigues Gurgel; Torres Ortega, Carlo Edgar; Rong, Ben-Guang

    2016-10-01

    In this work, a method based on process synthesis, simulation and evaluation has been used to setup and study the industrial scale lignocellulosic bioethanol productions processes. Scenarios for pretreatment processes of diluted acid, liquid hot water and ammonia fiber explosion were studied. Pretreatment reactor temperature, catalyst loading and water content as well as solids loading in the hydrolysis reactor were evaluated regarding its effects on the process energy consumption and bioethanol concentration. The best scenarios for maximizing ethanol concentration and minimizing total annual costs (TAC) were selected and their minimum ethanol selling price was calculated. Ethanol concentration in the range of 2-8% (wt.) was investigated after the pretreatment. The best scenarios maximizing the ethanol concentration and minimizing TAC obtained a reduction of 19.6% and 30.2% respectively in the final ethanol selling price with respect to the initial base case.

  12. Biorefinery of corn cob for microbial lipid and bio-ethanol production: An environmental friendly process.

    PubMed

    Cai, Di; Dong, Zhongshi; Wang, Yong; Chen, Changjing; Li, Ping; Qin, Peiyong; Wang, Zheng; Tan, Tianwei

    2016-07-01

    Microbial lipid and bio-ethanol were co-generated by an integrated process using corn cob bagasse as raw material. After pretreatment, the acid hydrolysate was used as substrate for microbial lipid fermentation, while the solid residue was further enzymatic hydrolysis for bio-ethanol production. The effect of acid loading and pretreatment time on microbial lipid and ethanol production were evaluated. Under the optimized condition for ethanol production, ∼131.3g of ethanol and ∼11.5g of microbial lipid were co-generated from 1kg raw material. On this condition, ∼71.6% of the overall fermentable sugars in corn cob bagasse could be converted into valuable products. At the same time, at least 33% of the initial COD in the acid hydrolysate was depredated.

  13. Comparison of different process strategies for bioethanol production from Eucheuma cottonii: An economic study.

    PubMed

    Tan, Inn Shi; Lee, Keat Teong

    2016-01-01

    The aim of this work was to evaluate the efficacy of red macroalgae Eucheuma cottonii (EC) as feedstock for third-generation bioethanol production. Dowex (TM) Dr-G8 was explored as a potential solid catalyst to hydrolyzed carbohydrates from EC or macroalgae extract (ME) and pretreatment of macroalgae cellulosic residue (MCR), to fermentable sugars prior to fermentation process. The highest total sugars were produced at 98.7 g/L when 16% of the ME was treated under the optimum conditions of solid acid hydrolysis (8% (w/v) Dowex (TM) Dr-G8, 120°C, 1h) and 2% pretreated MCR (P-MCR) treated by enzymatic hydrolysis (pH 4.8, 50°C, 30 h). A two-stream process resulted in 11.6g/L of bioethanol from the fermentation of ME hydrolysates and 11.7 g/L from prehydrolysis and simultaneous saccharification and fermentation of P-MCR. The fixed price of bioethanol obtained from the EC is competitive with that obtained from other feedstocks. Copyright © 2015 Elsevier Ltd. All rights reserved.

  14. Process Design and Costing of Bioethanol Technology: A Tool for Determining the Status and Direction of Research and Development.

    PubMed

    Wooley; Ruth; Glassner; Sheehan

    1999-10-01

    Bioethanol is a fuel-grade ethanol made from trees, grasses, and waste materials. It represents a sustainable substitute for gasoline in today's passenger cars. Modeling and design of processes for making bioethanol are critical tools used in the U.S. Department of Energy's bioethanol research and development program. We use such analysis to guide new directions for research and to help us understand the level at which and the time when bioethanol will achieve commercial success. This paper provides an update on our latest estimates for current and projected costs of bioethanol. These estimates are the result of very sophisticated modeling and costing efforts undertaken in the program over the past few years. Bioethanol could cost anywhere from $1.16 to $1.44 per gallon, depending on the technology and the availability of low cost feedstocks for conversion to ethanol. While this cost range opens the door to fuel blending opportunities, in which ethanol can be used, for example, to improve the octane rating of gasoline, it is not currently competitive with gasoline as a bulk fuel. Research strategies and goals described in this paper have been translated into cost savings for ethanol. Our analysis of these goals shows that the cost of ethanol could drop by 40 cents per gallon over the next ten years by taking advantage of exciting new tools in biotechnology that will improve yield and performance in the conversion process.

  15. Enhancing the Feasibility of Microcystis aeruginosa as a Feedstock for Bioethanol Production under the Influence of Various Factors

    PubMed Central

    Lee, Moon Geon; Seo, Hyo Jin; Shin, Jin Hyuk; Shin, Tai Sun; Kim, Min Yong; Choi, Jong Il

    2016-01-01

    Microcystis aeruginosa, a freshwater microalga, is capable of producing and accumulating different types of sugars in its biomass which make it a good feedstock for bioethanol production. Present study aims to investigate the effect of different factors increasing growth rate and carbohydrates productivity of M. aeruginosa. MF media (modified BG11 media) and additional ingredients such as aminolevulinic acid (2 mM), lysine (2.28 mM), alanine (1 mM), and Naphthalene acetic acid (1 mM) as cytokine promoted M. aeruginosa growth and sugar contents. Salmonella showed growth-assisting effect on M. aeruginosa. Enhanced growth rate and carbohydrates contents were observed in M. aeruginosa culture grown at 25°C under red LED light of 90 μmolm−2s−1 intensity. More greenish and carbohydrates rich M. aeruginosa biomass was prepared (final OD660 nm = 2.21 and sugar contents 10.39 mM/mL) as compared to control (maximum OD660 nm = 1.4 and sugar contents 3 mM/mL). The final algae biomass was converted to algae juice through a specific pretreatment method. The resulted algae Juice was used as a substrate in fermentation process. Highest yield of bioethanol (50 mM/mL) was detected when Brettanomyces custersainus, Saccharomyces cerevisiae, and Pichia stipitis were used in combinations for fermentation process as compared to their individual fermentation. The results indicated the influence of different factors on the growth rate and carbohydrates productivity of M. aeruginosa and its feasibility as a feedstock for fermentative ethanol production. PMID:27556034

  16. Enhancing the Feasibility of Microcystis aeruginosa as a Feedstock for Bioethanol Production under the Influence of Various Factors.

    PubMed

    Khan, Muhammad Imran; Lee, Moon Geon; Seo, Hyo Jin; Shin, Jin Hyuk; Shin, Tai Sun; Yoon, Yang Ho; Kim, Min Yong; Choi, Jong Il; Kim, Jong Deog

    2016-01-01

    Microcystis aeruginosa, a freshwater microalga, is capable of producing and accumulating different types of sugars in its biomass which make it a good feedstock for bioethanol production. Present study aims to investigate the effect of different factors increasing growth rate and carbohydrates productivity of M. aeruginosa. MF media (modified BG11 media) and additional ingredients such as aminolevulinic acid (2 mM), lysine (2.28 mM), alanine (1 mM), and Naphthalene acetic acid (1 mM) as cytokine promoted M. aeruginosa growth and sugar contents. Salmonella showed growth-assisting effect on M. aeruginosa. Enhanced growth rate and carbohydrates contents were observed in M. aeruginosa culture grown at 25°C under red LED light of 90 μmolm(-2)s(-1) intensity. More greenish and carbohydrates rich M. aeruginosa biomass was prepared (final OD660 nm = 2.21 and sugar contents 10.39 mM/mL) as compared to control (maximum OD660 nm = 1.4 and sugar contents 3 mM/mL). The final algae biomass was converted to algae juice through a specific pretreatment method. The resulted algae Juice was used as a substrate in fermentation process. Highest yield of bioethanol (50 mM/mL) was detected when Brettanomyces custersainus, Saccharomyces cerevisiae, and Pichia stipitis were used in combinations for fermentation process as compared to their individual fermentation. The results indicated the influence of different factors on the growth rate and carbohydrates productivity of M. aeruginosa and its feasibility as a feedstock for fermentative ethanol production.

  17. Optimization of Bioethanol Production Using Whole Plant of Water Hyacinth as Substrate in Simultaneous Saccharification and Fermentation Process.

    PubMed

    Zhang, Qiuzhuo; Weng, Chen; Huang, Huiqin; Achal, Varenyam; Wang, Duanchao

    2015-01-01

    Water hyacinth was used as substrate for bioethanol production in the present study. Combination of acid pretreatment and enzymatic hydrolysis was the most effective process for sugar production that resulted in the production of 402.93 mg reducing sugar at optimal condition. A regression model was built to optimize the fermentation factors according to response surface method in saccharification and fermentation (SSF) process. The optimized condition for ethanol production by SSF process was fermented at 38.87°C in 81.87 h when inoculated with 6.11 ml yeast, where 1.291 g/L bioethanol was produced. Meanwhile, 1.289 g/L ethanol was produced during experimentation, which showed reliability of presented regression model in this research. The optimization method discussed in the present study leading to relatively high bioethanol production could provide a promising way for Alien Invasive Species with high cellulose content.

  18. Optimization of Bioethanol Production Using Whole Plant of Water Hyacinth as Substrate in Simultaneous Saccharification and Fermentation Process

    PubMed Central

    Zhang, Qiuzhuo; Weng, Chen; Huang, Huiqin; Achal, Varenyam; Wang, Duanchao

    2016-01-01

    Water hyacinth was used as substrate for bioethanol production in the present study. Combination of acid pretreatment and enzymatic hydrolysis was the most effective process for sugar production that resulted in the production of 402.93 mg reducing sugar at optimal condition. A regression model was built to optimize the fermentation factors according to response surface method in saccharification and fermentation (SSF) process. The optimized condition for ethanol production by SSF process was fermented at 38.87°C in 81.87 h when inoculated with 6.11 ml yeast, where 1.291 g/L bioethanol was produced. Meanwhile, 1.289 g/L ethanol was produced during experimentation, which showed reliability of presented regression model in this research. The optimization method discussed in the present study leading to relatively high bioethanol production could provide a promising way for Alien Invasive Species with high cellulose content. PMID:26779125

  19. Selection of process alternatives for lignocellulosic bioethanol production using a MILP approach.

    PubMed

    Scott, Felipe; Venturini, Fabrizio; Aroca, Germán; Conejeros, Raúl

    2013-11-01

    This work proposes a decision-making framework for the selection of processes and unit operations for lignocellulosic bioethanol production. Process alternatives are described by its capital and operating expenditures, its contribution to process yield and technological availability information. A case study in second generation ethanol production using Eucalyptus globulus as raw material is presented to test the developed process synthesis tool. Results indicate that production cost does not necessarily decrease when yield increases. Hence, optimal processes can be found at the inflexion point of total costs and yield. The developed process synthesis tool provides results with an affordable computational cost, existing optimization tools and an easy-to-upgrade description of the process alternatives. These features made this tool suitable for process screening when incomplete information regarding process alternatives is available. Copyright © 2013 Elsevier Ltd. All rights reserved.

  20. Recent trends in bioethanol production from food processing byproducts.

    PubMed

    Akbas, Meltem Yesilcimen; Stark, Benjamin C

    2016-11-01

    The widespread use of corn starch and sugarcane as sources of sugar for the production of ethanol via fermentation may negatively impact the use of farmland for production of food. Thus, alternative sources of fermentable sugars, particularly from lignocellulosic sources, have been extensively investigated. Another source of fermentable sugars with substantial potential for ethanol production is the waste from the food growing and processing industry. Reviewed here is the use of waste from potato processing, molasses from processing of sugar beets into sugar, whey from cheese production, byproducts of rice and coffee bean processing, and other food processing wastes as sugar sources for fermentation to ethanol. Specific topics discussed include the organisms used for fermentation, strategies, such as co-culturing and cell immobilization, used to improve the fermentation process, and the use of genetic engineering to improve the performance of ethanol producing fermenters.

  1. Monitoring lignocellulosic bioethanol production processes using Raman spectroscopy.

    PubMed

    Iversen, Jens A; Ahring, Birgitte K

    2014-11-01

    Process control automation in the emerging biorefinery industry may be achieved by applying effective methods for monitoring compound concentrations during the production processes. This study examines the application of Raman spectroscopy with an excitation wavelength of 785nm and an immersion probe for in situ monitoring the progression of pretreatment, hydrolysis and fermentation processes in the production of lignocellulosic ethanol. Raman signals were attenuated by light scattering cells and lignocellulosic particulates, which the quantification method to some degree could correct for by using an internal standard in the spectra. Allowing particulates to settle by using a slow stirring speed further improved results, suggesting that Raman spectroscopy should be used in combination with continuous separation when used to monitor process mixtures with large amounts of particulates. The root mean square error of prediction (RMSE) of ethanol and glucose measured in real-time was determined to be 0.98g/L and 1.91g/L respectively.

  2. From wheat straw to bioethanol: integrative analysis of a separate hydrolysis and co-fermentation process with implemented enzyme production.

    PubMed

    Novy, Vera; Longus, Karin; Nidetzky, Bernd

    2015-01-01

    Lignocellulosic ethanol has a high potential as renewable energy source. In recent years, much research effort has been spent to optimize parameters involved in the production process. Despite that, there is still a lack of comprehensive studies on process integration. Single parameters and process configurations are, however, heavily interrelated and can affect the overall process efficiency in a multitude of ways. Here, we present an integrative approach for bioethanol production from wheat straw at a representative laboratory scale using a separate hydrolysis and co-fermentation (SHCF) process. The process does not rely on commercial (hemi-) cellulases but includes enzyme production through Hypocrea jecorina (formerly Trichoderma reesei) on the pre-treated feedstock as key unit operation. Hydrolysis reactions are run with high solid loadings of 15% dry mass pre-treated wheat straw (DM WS), and hydrolyzates are utilized without detoxification for mixed glucose-xylose fermentation with the genetically and evolutionary engineered Saccharomyces cerevisiae strain IBB10B05. Process configurations of unit operations in the benchtop SHCF were varied and evaluated with respect to the overall process ethanol yield (Y Ethanol-Process). The highest Y Ethanol-Process of 71.2 g ethanol per kg raw material was reached when fungal fermentations were run as batch, and the hydrolysis reaction was done with an enzyme loading of 30 filter paper units (FPU)/gDM WS. 1.7 ± 0.1 FPU/mL were produced, glucose and xylose were released with a conversion efficiency of 67% and 95%, respectively, and strain IBB10B05 showed an ethanol yield of 0.4 g/gGlc + Xyl in 15% hydrolyzate fermentations. Based on the detailed process analysis, it was further possible to identify the enzyme yield, the glucose conversion efficiency, and the mass losses between the unit operations as key process parameters, exhibiting a major influence on Y Ethanol-Process. Y Ethanol-Process is a measure for the

  3. Process design and economic analysis of a hypothetical bioethanol production plant using carob pod as feedstock.

    PubMed

    Sánchez-Segado, S; Lozano, L J; de Los Ríos, A P; Hernández-Fernández, F J; Godínez, C; Juan, D

    2012-01-01

    A process for the production of ethanol from carob (Ceratonia siliqua) pods was designed and an economic analysis was carried out for a hypothetical plant. The plant was assumed to perform an aqueous extraction of sugars from the pods followed by fermentation and distillation to produce ethanol. The total fixed capital investment for a base case process with a capacity to transform 68,000 t/year carob pod was calculated as 39.61 millon euros (€) with a minimum bioethanol production cost of 0.51 €/L and an internal rate of return of 7%. The plant was found to be profitable at carob pod prices lower than 0.188 €/kg. An increase in the transformation capacity of the plant from 33,880 to 135,450 t/year was calculated to result in an increase in the internal rate of return from 5.50% to 13.61%. The obtained results show that carob pod is a promising alternative source for bioethanol production. Copyright © 2011 Elsevier Ltd. All rights reserved.

  4. An environmentally friendly and productive process for bioethanol production from potato waste.

    PubMed

    Wang, Fangzhong; Jiang, Yi; Guo, Wei; Niu, Kangle; Zhang, Ruiqing; Hou, Shaoli; Wang, Mingyu; Yi, Yong; Zhu, Changxiong; Jia, Chunjiang; Fang, Xu

    2016-01-01

    China is the largest sweet potato producer and exporter in the world. Sweet potato residues (SPRs) separated after extracting starch account for more than 10 % of the total dry matter of sweet potatoes. In China, more than 2 million tons of SPRs cannot be utilized, and the unutilized SPRs are perishable and result in environmental pollution. Thus, an environmentally friendly and highly efficient process for bioethanol production from SPRs should be developed. The swelling behaviour of cellulose causes high-gravity sweet potato residues to be recalcitrant to enzymatic hydrolysis. Cellulase plays a major role in viscosity reduction and glucose production. In contrast, pectinase has a minor role in viscosity reduction but acts as a "helper protein" to assist cellulase in liberating glucose, especially at low cellulase activity levels. In total, 153.46 and 168.13 g/L glucose were produced from high-gravity SPRs with cellulase and a mixture of cellulase and pectinase, respectively. These hydrolysates were fermented to form 73.37 and 79.00 g/L ethanol, respectively. Each kilogram of dry SPR was converted to form 209.62 and 225.71 g of ethanol, respectively. The processes described in this study have an enormous potential for industrial production of bioethanol because they are environmentally friendly, highly productive, economic with low cost, and can be easily manipulated.

  5. Bio-ethanol production from wet coffee processing waste in Ethiopia.

    PubMed

    Woldesenbet, Asrat Gebremariam; Woldeyes, Belay; Chandravanshi, Bhagwan Singh

    2016-01-01

    Large amounts of coffee residues are generated from coffee processing plants in Ethiopia. These residues are toxic and possess serious environmental problems following the direct discharge into the nearby water bodies which cause serious environmental and health problems. This study was aimed to quantify wet coffee processing waste and estimate its bio-ethanol production. The study showed that the wastes are potential environmental problems and cause water pollution due to high organic component and acidic nature. The waste was hydrolyzed by dilute H2SO4 (0.2, 0.4, 0.6, 0.8 and 1 M) and distilled water. Total sugar content of the sample was determined titrimetrically and refractometry. Maximum value (90%) was obtained from hydrolysis by 0.4 M H2SO4. Ethanol production was monitored by gas chromatography. The optimum yield of ethanol (78%) was obtained from the sample hydrolyzed by 0.4 M H2SO4 for 1 h at hydrolysis temperature of 100 °C and after fermentation for 24 h and initial pH of 4.5. Based on the data, it was concluded that reuse of the main coffee industry wastes is of significant importance from environmental and economical view points. In conclusion, this study has proposed to utilize the wet coffee processing waste to produce bio-ethanol which provides the alternative energy source from waste biomass and solves the environmental waste disposal as well as human health problem.

  6. Novel two-stage fermentation process for bioethanol production using Saccharomyces pastorianus.

    PubMed

    Gowtham, Yogender Kumar; Miller, Kristen P; Hodge, David B; Henson, J Michael; Harcum, Sarah W

    2014-01-01

    Bioethanol produced from lignocellulosic materials has the potential to be economically feasible, if both glucose and xylose released from cellulose and hemicellulose can be efficiently converted to ethanol. Saccharomyces spp. can efficiently convert glucose to ethanol; however, xylose conversion to ethanol is a major hurdle due to lack of xylose-metabolizing pathways. In this study, a novel two-stage fermentation process was investigated to improve bioethanol productivity. In this process, xylose is converted into biomass via non-Saccharomyces microorganism and coupled to a glucose-utilizing Saccharomyces fermentation. Escherichia coli was determined to efficiently convert xylose to biomass, which was then killed to produce E. coli extract. Since earlier studies with Saccharomyces pastorianus demonstrated that xylose isomerase increased ethanol productivities on pure sugars, the addition of both E. coli extract and xylose isomerase to S. pastorianus fermentations on pure sugars and corn stover hydrolysates were investigated. It was determined that the xylose isomerase addition increased ethanol productivities on pure sugars but was not as effective alone on the corn stover hydrolysates. It was observed that the E. coli extract addition increased ethanol productivities on both corn stover hydrolysates and pure sugars. The ethanol productivities observed on the corn stover hydrolysates with the E. coli extract addition was the same as observed on pure sugars with both E. coli extract and xylose isomerase additions. These results indicate that the two-stage fermentation process has the capability to be a competitive alternative to recombinant Saccharomyces cerevisiae-based fermentations. © 2013 American Institute of Chemical Engineers.

  7. Techno-economic analysis of bioethanol production from lignocellulosic residues in Colombia: a process simulation approach.

    PubMed

    Quintero, Julián A; Moncada, Jonathan; Cardona, Carlos A

    2013-07-01

    In this study a techno-economic analysis of the production of bioethanol from four lignocellusic (Sugarcane bagasse, Coffee cut-stems, Rice Husk, and Empty Fruit Bunches) residues is presented for the Colombian case. The ethanol production was evaluated using Aspen Plus and Aspen Process Economic Analyzer carrying out the simulation and the economic evaluation, respectively. Simulations included the composition of lignocellulosic residues, which was determined experimentally. It was found that empty fruit bunches presents the highest ethanol yield from a dry basis point of view (313.83 L/t), while rice husk produced less ethanol (250.56 L/t). The ethanol production cost was assessed for the standalone ethanol plant and the ethanol plant coupled with a cogeneration system. Moreover, ethanol production cost using EFB was the lowest with (0.49 US$/L) and without (0.58 US$/L) cogeneration scheme. Copyright © 2013 Elsevier Ltd. All rights reserved.

  8. Improving bioethanol production from olive pruning biomass by deacetylation step prior acid hydrolysis and fermentation processes.

    PubMed

    Moya, Alberto J; Peinado, Silvia; Mateo, Soledad; Fonseca, Bruno G; Sánchez, Sebastián

    2016-11-01

    In order to produce bioethanol from olive tree pruning biomass, deacetylation was performed employing sodium hydroxide. Optimal conditions were determined using experimental design techniques. The highest acetic acid removal (3.8g/dm(3)), obtained by response surface methodology, was at optimum pretreatment conditions of temperature 60°C, 0.8% NaOH and residence time 60min. After oxalic acid hydrolysis of pretreated biomass, the hydrolysates were directly used for ethanol production without further detoxification process. Ethanol yields ranged from 0.19 to 0.45g/g, reaching the maximum yield value when pretreatment was carried out at 130°C with 100mM oxalic acid, involving a combined severity factor (CSF) of 1.05. The highest ethanol concentration obtained from pretreated biomass was 6.2g/dm(3) at 150°C, using 75mM of oxalic acid (CSF=1.53).

  9. Use of a dry fractionation process to manipulate the chemical profile and nutrient supply of a coproduct from bioethanol processing.

    PubMed

    Zhang, Xuewei; Beltranena, Eduardo; Christensen, Colleen; Yu, Peiqiang

    2012-07-11

    With an available processing technology (fractionation), coproducts from bioethanol processing (wheat dried distillers grains with solubles, DDGS) could be fractionated to a desired/optimal chemical and nutrient profile. There is no study, to the author's knowledge, on manipulating nutrient profiles through fractionation processing in bioethanol coproducts in ruminants. The objectives of this study were to investigate the effect of fractionation processing of a coproduct from bioethanol processing (wheat DDGS) on the metabolic characteristics of the proteins and to study the effects of fractionation processing on the magnitude of changes in chemical and nutrient supply to ruminants by comparing chemical and nutrient characterization, in situ rumen degradation kinetics, truly absorbed protein supply, and protein degraded balance among different fractions of coproduct of wheat DDGS. In this study, wheat DDGS was dry fractionationed into A, B, C, and D fractions according to particle size, gravity, and protein and fiber contents. The results showed that the fractionation processing changed wheat DDGS chemical and nutrient profiles. NDF and ADF increased from fraction A to D (NDF, from 330 to 424; ADF, from 135 to 175 g/kg DM). Subsequently, CP decreased (CP, from 499 to 363 g/kg DM), whereas soluble CP, NPN, and carbohydrate increased (SCP, from 247 to 304 g/kg CP; NPN, from 476 to 943 g/kg SCP; CHO, from 409 to 538 g/kg DM) from fraction A to D. The CNCPS protein and carbohydrate subfractions were also changed by the fractionation processing. Effective degradability of DM and CP and total digestible protein decreased from fraction A to D (EDDM, from 734 to 649; EDCP, from 321 to 241; TDP, from 442 to 312 g/kg DM). Total truly absorbed protein in the small intestine decreased from fraction A to D (DVE value, from 186 to 124 g/kg DM; MP in NRC-2001, from 193 to 136 g/kg DM). Degraded protein balance decreased from wheat DDGS fractions A-D (DPB in the DVE/OEB system

  10. Effects of fertilizer application and dry/wet processing of Miscanthus x giganteus on bioethanol production.

    PubMed

    Boakye-Boaten, Nana Abayie; Xiu, Shuangning; Shahbazi, Abolghasem; Wang, Lijun; Li, Rui; Mims, Michelle; Schimmel, Keith

    2016-03-01

    The effects of wet and dry processing of miscanthus on bioethanol production using simultaneous saccharification and fermentation (SSF) process were investigated, with wet samples showing higher ethanol yields than dry samples. Miscanthus grown with no fertilizer, with fertilizer and with swine manure were sampled for analysis. Wet-fractionation was used to separate miscanthus into solid and liquid fractions. Dilute sulfuric acid pretreatment was employed and the SSF process was performed with saccharomyces cerevisiae and a cocktail of enzymes at 35°C. After pretreatment, cellulose compositions of biomass of the wet samples increased from 61.0-67.0% to 77.0-87.0%, which were higher than the compositions of dry samples. The highest theoretical ethanol yield of 88.0% was realized for wet processed pretreated miscanthus, grown with swine manure. Changes to the morphology and chemical composition of the biomass samples after pretreatment, such as crystallinity reduction, were observed using SEM and FTIR. These changes improved ethanol production.

  11. Optimization of bio-ethanol autothermal reforming and carbon monoxide removal processes

    NASA Astrophysics Data System (ADS)

    Markova, D.; Bazbauers, G.; Valters, K.; Alhucema Arias, R.; Weuffen, C.; Rochlitz, L.

    Experimental investigation of bio-ethanol autothermal reforming (ATR) and water-gas shift (WGS) processes for hydrogen production and regression analysis of the data is performed in the study. The main goal was to obtain regression relations between the most critical dependent variables such as hydrogen, carbon monoxide and methane content in the reformate gas and independent factors such as air-to-fuel ratio (λ), steam-to-carbon ratio (S/C), inlet temperature of reactants into reforming process (T ATRin), pressure (p) and temperature (T ATR) in the ATR reactor from the experimental data. Purpose of the regression models is to provide optimum values of the process factors that give the maximum amount of hydrogen. The experimental ATR system consisted of an evaporator, an ATR reactor and a one-stage WGS reactor. Empirical relations between hydrogen, carbon monoxide, methane content and the controlling parameters downstream of the ATR reactor are shown in the work. The optimization results show that within the considered range of the process factors the maximum hydrogen concentration of 42 dry vol. % and yield of 3.8 mol mol -1 of ethanol downstream of the ATR reactor can be achieved at S/C = 2.5, λ = 0.20-0.23, p = 0.4 bar, T ATRin = 230 °C, T ATR = 640 °C.

  12. The effect of dilute acid pre-treatment process in bioethanol production from durian (Durio zibethinus) seeds waste

    NASA Astrophysics Data System (ADS)

    Ghazali, K. A.; Salleh, S. F.; Riayatsyah, T. M. I.; Aditiya, H. B.; Mahlia, T. M. I.

    2016-03-01

    Lignocellulosic biomass is one of the promising feedstocks for bioethanol production. The process starts from pre-treatment, hydrolysis, fermentation, distillation and finally obtaining the final product, ethanol. The efficiency of enzymatic hydrolysis of cellulosic biomass depends heavily on the effectiveness of the pre-treatment step which main function is to break the lignin structure of the biomass. This work aims to investigate the effects of dilute acid pre-treatment on the enzymatic hydrolysis of durian seeds waste to glucose and the subsequent bioethanol fermentation process. The yield of glucose from dilute acid pre-treated sample using 0.6% H2SO4 and 5% substrate concentration shows significant value of 23.4951 g/L. Combination of dilute acid pre-treatment and enzymatic hydrolysis using 150U of enzyme able to yield 50.0944 g/L of glucose content higher compared to normal pre-treated sample of 8.1093 g/L. Dilute acid pre-treatment sample also shows stable and efficient yeast activity during fermentation process with lowest glucose content at 2.9636 g/L compared to 14.7583g/L for normal pre-treated sample. Based on the result, it can be concluded that dilute acid pre-treatment increase the yield of ethanol from bioethanol production process.

  13. An improved CARV process for bioethanol production from a mixture of sugar beet mash and potato mash.

    PubMed

    Yun, Min-Soo; Park, Jeung-yil; Arakane, Mitsuhiro; Shiroma, Riki; Ike, Masakazu; Tamiya, Seiji; Takahashi, Hiroyuki; Tokuyasu, Ken

    2011-01-01

    A mixed mash of sugar beet roots and potato tubers with a sugar concentration of 23.7% w/v was used as a feedstock for bioethanol production. Enzymatic digestion successfully reduced the viscosity of the mixture, enabling subsequent heat pretreatment for liquefaction/sterilization. An energy-consuming thick juice preparation from sugar beet for concentration and sterilization was omitted in this new process.

  14. Development of an integrated process to produce d-mannose and bioethanol from coffee residue waste.

    PubMed

    Nguyen, Quynh Anh; Cho, Eunjin; Trinh, Ly Thi Phi; Jeong, Ji-Su; Bae, Hyeun-Jong

    2017-08-03

    A novel, integrated process for economical high-yield production of d-mannose and ethanol from coffee residue waste (CRW), which is abundant and widely available, was reported. The process involves pretreatment, enzymatic hydrolysis, fermentation, color removal, and pervaporation, which can be performed using environmentally friendly technologies. The CRW was pretreated with ethanol at high temperature and then hydrolyzed with enzymes produced in-house to yield sugars. Key points of the process are: manipulations of the fermentation step that allowing bioethanol-producing yeasts to use almost glucose and galactose to produce ethanol, while retaining large amounts of d-mannose in the fermented broth; removal of colored compounds and other components from the fermented broth; and separation of ethanol and d-mannose through pervaporation. Under optimized conditions, approximately 15.7g dry weight (DW) of d-mannose (approximately 46% of the mannose) and approximately 11.3g DW of ethanol from 150g DW of ethanol-pretreated CRW, were recovered. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. Efficacy of a hot washing process for pretreated yellow poplar to enhance bioethanol production.

    PubMed

    Nagle, Nicholas J; Elander, Richard T; Newman, Mildred M; Rohrback, Brian T; Ruiz, Raymond O; Torget, Robert W

    2002-01-01

    Cost reductions for pretreatment and bioconversion processes are key objectives necessary to the successful deployment of a bioethanol industry. These unit operations have long been recognized for their impact on the production cost of ethanol. One strategy to achieve this objective is to improve the pretreatment process to produce a pretreated substrate resulting in reduced bioconversion time, lower cellulase enzyme usage, and/or higher ethanol yields. Previous research produced a highly digestible pretreated yellow poplar substrate using a multistage, continuously flowing, very dilute sulfuric acid (0.07% (w/v)) pretreatment. This process reduced the time required for the bioconversion of pretreated yellow poplar sawdust to ethanol. This resulted in a substantially improved yield of ethanol from cellulose. However, the liquid volume requirements, steam demand, and complexity of the flow-through reactor configuration were determined to be serious barriers to commercialization of that process. A reconfigured process to achieve similar performance has been developed using a single-stage batch pretreatment followed by a separation of solids and liquids and washing of the solids at a temperatures between 130 and 150 degrees C. Separation and washing at the elevated temperature is believed to prevent a large fraction of the solubilized lignin and xylan from reprecipitating and/or reassociating with the pretreated solids. This washing of the solids at elevated temperature resulted in both higher recovered yields of soluble xylose sugars and a more digestible pretreated substrate for enzymatic hydrolysis. Key operating variables and process performance indicators included acid concentration, temperature, wash volume, wash temperature, soluble xylose recovery, and performance of the washed, pretreated solids in bioconversion via simultaneous saccharification and fermentation (SSF). Initial results indicated over a 50% increase in ethanol yield at 72 h for the hot washed

  16. Degradation of black liquor from bioethanol process using coagulation and Fenton-like methods

    NASA Astrophysics Data System (ADS)

    Muryanto, Muryanto; Sari, Ajeng Arum; Abimanyu, Haznan

    2017-01-01

    Black liquor is one of the main by-products of the pretreatment process in bioethanol production from oil palm empty fruit bunches. Black liquor wastewater releases black coloured effluent with high chemical oxygen demand (COD) and low dissolved oxygen (DO). It had a distinctive dark coloration, high alkalinity (pH=13), high organic content (COD > 50,000 ppm) and a high solid content (TSS > 5,000 ppm). Lignin destruction can be done by using high oxidation from OH radical system such as advanced oxidation processes (AOPs). Thereafter, the high concentration of COD, color, and TSS can be removed. The general aim of the present investigation was to determine degradation of black liquor wastewater by using a combined coagulation and Fenton-like methods. In this research, we use Poly Aluminum Chloride (PAC) as a coagulant and FeCl3.6H2O and H2O2 for Fenton-like's reagent. The process was conducted in jar test at 200 rpm for 30 minutes and after that slowly mixed for 2 hours and left for sedimentation 24 hours. 50 ml black liquor was added with variation dose of 1-5% PAC, and 10 % Fenton-like reagent. Hydroxyl radical was generated by the Fenton-like's reagent (ratio FeCl3.6H2O : H2O2 was varied). The highest decolorization of black liquor 70 % was obtained under 5% PAC coagulant. The pH of the wastewater was reduced from 13.00 to 8.07 after the addition of the coagulant. The decolorization of original black liquor was approximately 58% through the Fenton-like process. The combination of PAC and Fenton-like reagent has able to enhance the decolorization of black liquor up to 97%.

  17. Bioethanol production from steam-pretreated corn stover through an isomerase mediated process.

    PubMed

    De Bari, Isabella; Cuna, Daniela; Di Matteo, Vincenzo; Liuzzi, Federico

    2014-03-25

    Agricultural by-products such as corn stover are considered strategic raw materials for the production of second-generation bioethanol from renewable and non-food sources. This paper describes the conversion of steam-pretreated corn stover to ethanol utilising a multi-step process including enzymatic hydrolysis, isomerisation, and fermentation of mixed hydrolysates with native Saccharomyces cerevisiae. An immobilised isomerase enzyme was used for the xylose isomerisation along with high concentrations of S. cerevisiae. The objective was to assess the extent of simultaneity of the various conversion steps, through a detailed analysis of process time courses, and to test this process scheme for the conversion of lignocellulosic hydrolysates containing several inhibitors of the isomerase enzyme (e.g. metal ions, xylitol and glycerol). The process was tested on two types of hydrolysate after acid-catalysed steam pretreatment: (a) the water soluble fraction (WSF) in which xylose was the largest carbon source and (b) the entire slurry, containing both cellulose and hemicellulose carbohydrates, in which glucose predominated. The results indicated that the ethanol concentration rose when the inoculum concentration was increased in the range 10-75 g/L. However, when xylose was the largest carbon source, the metabolic yields were higher than 0.51g(ethanol)/g(consumed) sugars probably due to the use of yeast internal cellular resources. This phenomenon was not observed in the fermentation of mixed hydrolysates obtained from the entire pretreated product and in which glucose was the largest carbon source. The ethanol yield from biomass suspensions with dry matter (DM) concentrations of 11-12% (w/v) was 70% based on total sugars (glucose, xylose, galactose). The results suggest that xylulose uptake was more effective in mixed hydrolysates containing glucose levels similar to, or higher than, xylose. Analysis of the factors that limit isomerase activity in lignocellulosic

  18. Viability assessment of regional biomass pre-processing center based bioethanol value chains

    NASA Astrophysics Data System (ADS)

    Carolan, Joseph E.

    Petroleum accounts for 94% of all liquid fuels and 36% of the total of all energy consumed in the United States. Petroleum dependence is problematic because global petroleum reserves are estimated to last only for 40 to 60 years at current consumption rates; global supplies are often located in politically unstable or unfriendly regions; and fossil fuels have negative environmental footprints. Domestic policies have aimed at promoting alternative, renewable liquid fuels, specifically bio-fuels derived from organic matter. Cellulosic bio-ethanol is one promising alternative fuel that has featured prominently in federal bio-fuel mandates under the Energy Independence and Security Act, 2007. However, the cellulosic bio-ethanol industry faces several technical, physical and industrial organization challenges. This dissertation examines the concept of a network of regional biomass pre-treatment centers (RBPC) that form an extended biomass supply chain feeding into a simplified biorefinery as a way to overcome these challenges. The analyses conducted address the structural and transactional issues facing bio-ethanol value chain establishment; the technical and financial feasibility of a stand alone pre-treatment center (RBPC); the impact of distributed pre-treatment on biomass transport costs; a comparative systems cost evaluation of the performance of the RBPC chain versus a fully integrated biorefinery (gIBRh), followed by application of the analytical framework to three case study regions.

  19. Production and Purification of Bioethanol from Molasses and Cassava

    NASA Astrophysics Data System (ADS)

    Maryana, Roni; Wahono, Satriyo Krido

    2009-09-01

    This research aim to analysis bioethanol purification process. Bioethanol from cassava has been produced in previous research and the ethanol from molasses was taken from Bekonang region. The production of bioethanol from cassava was carried out through several processes such as homogenization, adding of α-amylase, β-amylase and yeast (Saccharomyces c). Two types of laboratory scale distillator have been used, the first type is 50 cm length and 4 cm diameter. The second type distillator is 30 cm length and 9 cm diameter. Both types have been used to distill bioethanol The initial concentration after the fermentation process is 15% for bioethanol from cassava and 20-30% ethanol from molasses. The results of first type distillator are 90% of bioethanol at 50° C and yield 2.5%; 70% of bioethanol at 60° C and yield 11.2%. 32% of bioethanol at 70° C and yield 42%. Meanwhile the second distillator results are 84% of bioethanol at 50° C with yield 12%; 51% of bioethanol at 60° C with yield 35.5%; 20% of bioethanol at 70° C with yield 78.8%; 16% of bioethanol at 80° C with yield 81.6%. The ethanol from molasses has been distillated once times in Bekonang after the fermentation process, the yield was about 20%. In this research first type distillator and the initial concentration is 20% has been used. The results are 95% of bioethanol at 75° C with yield 8%; 94% of bioethanol at 85° C with yield 13% when vacuum pump was used. And 94% of bioethanol at 90° C with yield 3.7% and 94% of bioethanol at 96° C with yield 10.27% without vacuum pump. The bioethanol purification use second type distillator more effective than first type distillator.

  20. New Estimates of Land Use Intensity of Potential Bioethanol Production in the U.S.A.

    NASA Astrophysics Data System (ADS)

    Kheshgi, H. S.; Song, Y.; Torkamani, S.; Jain, A. K.

    2016-12-01

    We estimate potential bioethanol land use intensity (the inverse of potential bioethanol yield per hectare) across the United States by modeling crop yields and conversion to bioethanol (via a fermentation pathway), based on crop field studies and conversion technology analyses. We apply the process-based land surface model, the Integrated Science Assessment model (ISAM), to estimate the potential yield of four crops - corn, Miscanthus, and two variants of switchgrass (Cave-in-Rock and Alamo) - across the U.S.A. landscape for the 14-year period from 1999 through 2012, for the case with fertilizer application but without irrigation. We estimate bioethanol yield based on recent experience for corn bioethanol production from corn kernel, and current cellulosic bioethanol process design specifications under the assumption of the maximum practical harvest fraction for the energy grasses (Miscanthus and switchgrasses) and a moderate (30%) harvest fraction of corn stover. We find that each of four crops included has regions where that crop is estimated to have the lowest land use intensity (highest potential bioethanol yield per hectare). We find that minimizing potential land use intensity by including both corn and the energy grasses only improves incrementally to that of corn (using both harvested kernel and stover for bioethanol). Bioethanol land use intensity is one fundamental factor influencing the desirability of biofuels, but is not the only one; others factors include economics, competition with food production and land use, water and climate, nitrogen runoff, life-cycle emissions, and the pace of crop and technology improvement into the future.

  1. A spatially explicit whole-system model of the lignocellulosic bioethanol supply chain: an assessment of decentralised processing potential.

    PubMed

    Dunnett, Alex J; Adjiman, Claire S; Shah, Nilay

    2008-07-28

    Lignocellulosic bioethanol technologies exhibit significant capacity for performance improvement across the supply chain through the development of high-yielding energy crops, integrated pretreatment, hydrolysis and fermentation technologies and the application of dedicated ethanol pipelines. The impact of such developments on cost-optimal plant location, scale and process composition within multiple plant infrastructures is poorly understood. A combined production and logistics model has been developed to investigate cost-optimal system configurations for a range of technological, system scale, biomass supply and ethanol demand distribution scenarios specific to European agricultural land and population densities. Ethanol production costs for current technologies decrease significantly from $0.71 to $0.58 per litre with increasing economies of scale, up to a maximum single-plant capacity of 550 x 106 l year-1. The development of high-yielding energy crops and consolidated bio-processing realises significant cost reductions, with production costs ranging from $0.33 to $0.36 per litre. Increased feedstock yields result in systems of eight fully integrated plants operating within a 500 x 500 km2 region, each producing between 1.24 and 2.38 x 109 l year-1 of pure ethanol. A limited potential for distributed processing and centralised purification systems is identified, requiring developments in modular, ambient pretreatment and fermentation technologies and the pipeline transport of pure ethanol. The conceptual and mathematical modelling framework developed provides a valuable tool for the assessment and optimisation of the lignocellulosic bioethanol supply chain. In particular, it can provide insight into the optimal configuration of multiple plant systems. This information is invaluable in ensuring (near-)cost-optimal strategic development within the sector at the regional and national scale. The framework is flexible and can thus accommodate a range of processing

  2. A spatially explicit whole-system model of the lignocellulosic bioethanol supply chain: an assessment of decentralised processing potential

    PubMed Central

    Dunnett, Alex J; Adjiman, Claire S; Shah, Nilay

    2008-01-01

    Background Lignocellulosic bioethanol technologies exhibit significant capacity for performance improvement across the supply chain through the development of high-yielding energy crops, integrated pretreatment, hydrolysis and fermentation technologies and the application of dedicated ethanol pipelines. The impact of such developments on cost-optimal plant location, scale and process composition within multiple plant infrastructures is poorly understood. A combined production and logistics model has been developed to investigate cost-optimal system configurations for a range of technological, system scale, biomass supply and ethanol demand distribution scenarios specific to European agricultural land and population densities. Results Ethanol production costs for current technologies decrease significantly from $0.71 to $0.58 per litre with increasing economies of scale, up to a maximum single-plant capacity of 550 × 106 l year-1. The development of high-yielding energy crops and consolidated bio-processing realises significant cost reductions, with production costs ranging from $0.33 to $0.36 per litre. Increased feedstock yields result in systems of eight fully integrated plants operating within a 500 × 500 km2 region, each producing between 1.24 and 2.38 × 109 l year-1 of pure ethanol. A limited potential for distributed processing and centralised purification systems is identified, requiring developments in modular, ambient pretreatment and fermentation technologies and the pipeline transport of pure ethanol. Conclusion The conceptual and mathematical modelling framework developed provides a valuable tool for the assessment and optimisation of the lignocellulosic bioethanol supply chain. In particular, it can provide insight into the optimal configuration of multiple plant systems. This information is invaluable in ensuring (near-)cost-optimal strategic development within the sector at the regional and national scale. The framework is flexible and can thus

  3. The influence of light intensity and photoperiod on duckweed biomass and starch accumulation for bioethanol production.

    PubMed

    Yin, Yehu; Yu, Changjiang; Yu, Li; Zhao, Jinshan; Sun, Changjiang; Ma, Yubin; Zhou, Gongke

    2015-01-01

    Duckweed has been considered as a valuable feedstock for bioethanol production due to its high biomass and starch production. To investigate the effects of light conditions on duckweed biomass and starch production, Lemna aequinoctialis 6000 was cultivated at different photoperiods (12:12, 16:8 and 24:0h) and light intensities (20, 50, 80, 110, 200 and 400μmolm(-2)s(-1)). The results showed that the duckweed biomass and starch production was increased with increasing light intensity and photoperiod except at 200 and 400μmolm(-2)s(-1). Considering the light cost, 110μmolm(-2)s(-1) was optimum light condition for starch accumulation with the highest maximum growth rate, biomass and starch production of 8.90gm(-2)day(-1), 233.25gm(-2) and 98.70gm(-2), respectively. Moreover, the results suggested that high light induction was a promising method for duckweed starch accumulation. This study provides optimized light conditions for future industrial large-scale duckweed cultivation. Copyright © 2015 Elsevier Ltd. All rights reserved.

  4. Valorizing recycled paper sludge by a bioethanol production process with cellulase recycling.

    PubMed

    Gomes, Daniel; Domingues, Lucília; Gama, Miguel

    2016-09-01

    The feasibility of cellulase recycling in the scope of bioethanol production from recycled paper sludge (RPS), an inexpensive byproduct with around 39% of carbohydrates, is analyzed. RPS was easily converted and fermented by enzymes and cells, respectively. Final enzyme partition between solid and liquid phases was investigated, the solid-bound enzymes being efficiently recovered by alkaline washing. RPS hydrolysis and fermentation was conducted over four rounds, recycling the cellulases present in both fractions. A great overall enzyme stability was observed: 71, 64 and 100% of the initial Cel7A, Cel7B and β-glucosidase activities, respectively, were recovered. Even with only 30% of fresh enzymes added on the subsequent rounds, solid conversions of 92, 83 and 71% were achieved for the round 2, 3 and 4, respectively. This strategy enabled an enzyme saving around 53-60%, while can equally contribute to a 40% reduction in RPS disposal costs.

  5. Techno-economic evaluation of 2nd generation bioethanol production from sugar cane bagasse and leaves integrated with the sugar-based ethanol process

    PubMed Central

    2012-01-01

    Background Bioethanol produced from the lignocellulosic fractions of sugar cane (bagasse and leaves), i.e. second generation (2G) bioethanol, has a promising market potential as an automotive fuel; however, the process is still under investigation on pilot/demonstration scale. From a process perspective, improvements in plant design can lower the production cost, providing better profitability and competitiveness if the conversion of the whole sugar cane is considered. Simulations have been performed with AspenPlus to investigate how process integration can affect the minimum ethanol selling price of this 2G process (MESP-2G), as well as improve the plant energy efficiency. This is achieved by integrating the well-established sucrose-to-bioethanol process with the enzymatic process for lignocellulosic materials. Bagasse and leaves were steam pretreated using H3PO4 as catalyst and separately hydrolysed and fermented. Results The addition of a steam dryer, doubling of the enzyme dosage in enzymatic hydrolysis, including leaves as raw material in the 2G process, heat integration and the use of more energy-efficient equipment led to a 37 % reduction in MESP-2G compared to the Base case. Modelling showed that the MESP for 2G ethanol was 0.97 US$/L, while in the future it could be reduced to 0.78 US$/L. In this case the overall production cost of 1G + 2G ethanol would be about 0.40 US$/L with an output of 102 L/ton dry sugar cane including 50 % leaves. Sensitivity analysis of the future scenario showed that a 50 % decrease in the cost of enzymes, electricity or leaves would lower the MESP-2G by about 20%, 10% and 4.5%, respectively. Conclusions According to the simulations, the production of 2G bioethanol from sugar cane bagasse and leaves in Brazil is already competitive (without subsidies) with 1G starch-based bioethanol production in Europe. Moreover 2G bioethanol could be produced at a lower cost if subsidies were used to compensate for the opportunity cost from the

  6. Techno-economic evaluation of 2nd generation bioethanol production from sugar cane bagasse and leaves integrated with the sugar-based ethanol process.

    PubMed

    Macrelli, Stefano; Mogensen, Johan; Zacchi, Guido

    2012-04-13

    Bioethanol produced from the lignocellulosic fractions of sugar cane (bagasse and leaves), i.e. second generation (2G) bioethanol, has a promising market potential as an automotive fuel; however, the process is still under investigation on pilot/demonstration scale. From a process perspective, improvements in plant design can lower the production cost, providing better profitability and competitiveness if the conversion of the whole sugar cane is considered. Simulations have been performed with AspenPlus to investigate how process integration can affect the minimum ethanol selling price of this 2G process (MESP-2G), as well as improve the plant energy efficiency. This is achieved by integrating the well-established sucrose-to-bioethanol process with the enzymatic process for lignocellulosic materials. Bagasse and leaves were steam pretreated using H3PO4 as catalyst and separately hydrolysed and fermented. The addition of a steam dryer, doubling of the enzyme dosage in enzymatic hydrolysis, including leaves as raw material in the 2G process, heat integration and the use of more energy-efficient equipment led to a 37 % reduction in MESP-2G compared to the Base case. Modelling showed that the MESP for 2G ethanol was 0.97 US$/L, while in the future it could be reduced to 0.78 US$/L. In this case the overall production cost of 1G + 2G ethanol would be about 0.40 US$/L with an output of 102 L/ton dry sugar cane including 50 % leaves. Sensitivity analysis of the future scenario showed that a 50 % decrease in the cost of enzymes, electricity or leaves would lower the MESP-2G by about 20%, 10% and 4.5%, respectively. According to the simulations, the production of 2G bioethanol from sugar cane bagasse and leaves in Brazil is already competitive (without subsidies) with 1G starch-based bioethanol production in Europe. Moreover 2G bioethanol could be produced at a lower cost if subsidies were used to compensate for the opportunity cost from the sale of excess electricity and

  7. Study the sensitivity of molecular functional groups to bioethanol processing in lipid biopolymer of co-products using DRIFT molecular spectroscopy.

    PubMed

    Yu, Peiqiang

    2011-11-01

    To date, there is no study on bioethanol processing-induced changes in molecular structural profiles mainly related to lipid biopolymer. The objectives of this study were to: (1) determine molecular structural changes of lipid related functional groups in the co-products that occurred during bioethanol processing; (2) relatively quantify the antisymmetric CH(3) and CH(2) (ca. 2959 and 2928 cm(-1), respectively), symmetric CH(3) and CH(2) (ca. 2871 and 2954 cm(-1), respectively) functional groups, carbonyl C=O ester (ca. 1745 cm(-1)) and unsaturated groups (CH attached to C=C) (ca. 3007 cm(-1)) spectral intensities as well as their ratios of antisymmetric CH(3) to antisymmetric CH(2), and (3) illustrate the molecular spectral analyses as a research tool to detect for the sensitivity of individual moleculars to the bioethanol processing in a complex plant-based feed and food system without spectral parameterization. The hypothesis of this study was that bioethanol processing changed the molecular structure profiles in the co-products as opposed to original cereal grains. These changes could be detected by infrared molecular spectroscopy and will be related to nutrient utilization. The results showed that bioethanol processing had effects on the functional groups spectral profiles in the co-products. It was found that the CH(3)-antisymmetric to CH(2)-antisymmetric stretching intensity ratio was changed. The spectral features of carbonyl C=O ester group and unsaturated group were also different. Since the different types of cereal grains (wheat vs. corn) had different sensitivity to the bioethanol processing, the spectral patterns and band component profiles differed between their co-products (wheat DDGS vs. corn DDGS). The multivariate molecular spectral analyses, cluster analysis and principal component analysis of original spectra (without spectral parameterization), distinguished the structural differences between the wheat and wheat DDGS and between the corn and

  8. Study the sensitivity of molecular functional groups to bioethanol processing in lipid biopolymer of co-products using DRIFT molecular spectroscopy

    NASA Astrophysics Data System (ADS)

    Yu, Peiqiang

    2011-11-01

    To date, there is no study on bioethanol processing-induced changes in molecular structural profiles mainly related to lipid biopolymer. The objectives of this study were to: (1) determine molecular structural changes of lipid related functional groups in the co-products that occurred during bioethanol processing; (2) relatively quantify the antisymmetric CH 3 and CH 2 (ca. 2959 and 2928 cm -1, respectively), symmetric CH 3 and CH 2 (ca. 2871 and 2954 cm -1, respectively) functional groups, carbonyl C dbnd O ester (ca. 1745 cm -1) and unsaturated groups (CH attached to C dbnd C) (ca. 3007 cm -1) spectral intensities as well as their ratios of antisymmetric CH 3 to antisymmetric CH 2, and (3) illustrate the molecular spectral analyses as a research tool to detect for the sensitivity of individual moleculars to the bioethanol processing in a complex plant-based feed and food system without spectral parameterization. The hypothesis of this study was that bioethanol processing changed the molecular structure profiles in the co-products as opposed to original cereal grains. These changes could be detected by infrared molecular spectroscopy and will be related to nutrient utilization. The results showed that bioethanol processing had effects on the functional groups spectral profiles in the co-products. It was found that the CH 3-antisymmetric to CH 2-antisymmetric stretching intensity ratio was changed. The spectral features of carbonyl C dbnd O ester group and unsaturated group were also different. Since the different types of cereal grains (wheat vs. corn) had different sensitivity to the bioethanol processing, the spectral patterns and band component profiles differed between their co-products (wheat DDGS vs. corn DDGS). The multivariate molecular spectral analyses, cluster analysis and principal component analysis of original spectra (without spectral parameterization), distinguished the structural differences between the wheat and wheat DDGS and between the corn

  9. Effect of reduction in yeast and enzyme concentrations in a simultaneous- saccharification-and-fermentation-based bioethanol process: technical and economic evaluation.

    PubMed

    Wingren, Anders; Galbe, Mats; Roslander, Christian; Rudolf, Andreas; Zacchi, Guido

    2005-01-01

    The ethanol production cost in a simultaneous saccharification and fermentation-based bioethanol process is influenced by the requirements for yeast production and for enzymes. The main objective of this study was to evaluate--technically and economically--the influence of these two factors on the production cost. A base case with 5 g/L of baker's yeast and an initial concentration of water-insoluble solids of 5% resulted in an experimental yield of 85%. When these data were implemented in Aspen Plus, yeast was assumed to be produced from sugars in the hydrolysate, reducing the overall ethanol yield to 69%. The ethanol production cost was 4.80 SEK/L (2.34 US$/gal). When adapted yeast was used at 2 g/L, an experimental yield of 74% was achieved and the estimated ethanol production cost was the same as in the base case. A 50% reduction in enzyme addition resulted in an increased production cost, to 5.06 SEK/L (2.47 US$/gal) owing to reduced ethanol yield.

  10. A novel full recycling process through two-stage anaerobic treatment of distillery wastewater for bioethanol production from cassava.

    PubMed

    Zhang, Qing-Hua; Lu, Xin; Tang, Lei; Mao, Zhong-Gui; Zhang, Jian-Hua; Zhang, Hong-Jian; Sun, Fu-Bao

    2010-07-15

    In the present study, a novel full recycling process for bioethanol production was investigated, where three mathematical models were established to simulate the accumulation of major soluble inhibitory substances, including organic compounds, total ions, volatile fatty acids (VFAs) and colorants. These inhibitory substances in the reused water reached a relative steady state after 3-7 batches of anaerobic treatment and recycling process, which coincided with the results of mathematical models. There were no negative effects of these inhibitory substances on ethanol fermentation and the final ethanol yield, fermentation time, starch utilization ratio were very close to that of the conventional process using tap water. However, approximately 7.54% (w/w) of water was lost during each circulation, which was replenished in subsequent circulations, to assure consistent fermentation broth volume. This novel process was confirmed to have a stable operation over 13 recycles. It is concluded the stable states of the inhibitory substances in the reused water can assure this recycling process will run successfully. 2010 Elsevier B.V. All rights reserved.

  11. Cell-recycle batch process of Scheffersomyces stipitis and Saccharomyces cerevisiae co-culture for second generation bioethanol production.

    PubMed

    Ashoor, Selim; Comitini, Francesca; Ciani, Maurizio

    2015-11-01

    To achieve an optimized co-culture ratio of Scheffersomyces stipitis and Saccharomyces cerevisiae for the production of second generation bioethanol under a cell-recycle batch process. Three Sacc. cerevisiae strains were evaluated in co-culture with Sch. stipitis CBS 5773 at different ratios using synthetic medium containing glucose and xylose. Bioreactor trials indicated that the optimal condition for ethanol production using Sacc. cerevisiae EC1118 and Sch. stipitis co-culture was 1 % of O2 concentration. To increase ethanol production with Sacc. cerevisiae/Sch. stipitis co-culture a cell-recycle batch process was evaluated. Using this process, the maximum ethanol production (9.73 g l(-1)) and ethanol yield (0.42 g g(-1)) were achieved exhibiting a tenfold increase in ethanol productivity in comparison with batch process (2.1 g l(-1) h(-1)). In these conditions a stabilization of the cells ratio Sacc. cerevisiae/Sch. stipitis (1:5) at steady state condition was obtained. Batch cells recycling fermentation is an effective process to use Sch. stipitis/Sacc. cerevisiae co-culture for second generation ethanol production.

  12. Process design and optimization of novel wheat-based continuous bioethanol production system.

    PubMed

    Arifeen, Najmul; Wang, Ruohang; Kookos, Ioannis K; Webb, Colin; Koutinas, Apostolis A

    2007-01-01

    A novel design of a wheat-based biorefinery for bioethanol production, including wheat milling, gluten extraction as byproduct, fungal submerged fermentation for enzyme production, starch hydrolysis, fungal biomass autolysis for nutrient regeneration, yeast fermentation with recycling integrated with a pervaporation membrane for ethanol concentration, and fuel-grade ethanol purification by pressure swing distillation (PSD), was optimized in continuous mode using the equation-based software General Algebraic Modelling System (GAMS). The novel wheat biorefining strategy could result in a production cost within the range of dollars 0.96-0.50 gal(-1) ethanol (dollars 0.25-0.13 L(-1) ethanol) when the production capacity of the plant is within the range of 10-33.5 million gal y(-1) (37.85-126.8 million L y(-1)). The production of value-added byproducts (e.g., bran-rich pearlings, gluten, pure yeast cells) was identified as a crucial factor for improving the economics of fuel ethanol production from wheat. Integration of yeast fermentation with pervaporation membrane could result in the concentration of ethanol in the fermentation outlet stream (up to 40 mol %). The application of a PSD system that consisted of a low-pressure and a high-pressure column and employing heat integration between the high- and low-pressure columns resulted in reduced operating cost (up to 44%) for fuel-grade ethanol production.

  13. Determination of two-liquid mixture composition by assessing its dielectric parameters 2. modified measuring system for monitoring the dehydration process of bioethanol production

    NASA Astrophysics Data System (ADS)

    Vilitis, O.; Shipkovs, P.; Merkulovs, D.; Rucins, A.; Zihmane-Ritina, K.; Bremers, G.

    2014-02-01

    In Part 2 of the work we describe a modified measuring system for precise monitoring of the dehydration process of bioethanol production. This is based on the earlier proposed system for measuring the concentration of solutions and two-liquid mixtures using devices with capacitive sensors (1-300pF), which provides a stable measuring resolution of ± 0.005 pF at measuring the capacitance of a sensor. In this part of our work we determine additional requirements that are to be imposed on the measuring system at monitoring the ethanol dehydration process and control of bioethanol production. The most important parameters of the developed measuring system are identified. An exemplary calculation is given for the thermocompensated calibration of measuring devices. The results of tests have shown a good performance of the developed measuring system.

  14. Integration of the first and second generation bioethanol processes and the importance of by-products.

    PubMed

    Lennartsson, Patrik R; Erlandsson, Per; Taherzadeh, Mohammad J

    2014-08-01

    Lignocellulosic ethanol has obstacles in the investment costs and uncertainties in the process. One solution is to integrate it with the running dry mills of ethanol from grains. However, the economy of these mills, which dominate the world market, are dependent on their by-products DDGS (Distiller's Dried Grains and Solubles), sold as animal feed. The quality of DDGS therefore must not be negatively influenced by the integration. This puts restraints on the choice of pretreatment of lignocelluloses and utilizing the pentose sugars by food-grade microorganisms. The proposed solution is to use food related filamentous Zygomycetes and Ascomycetes fungi, and to produce fungal biomass as a high-grade animal feed from the residues after the distillation (stillage). This also has the potential to improve the first generation process by increasing the amount of the thin stillage directly sent back into the process, and by decreasing the evaporator based problems.

  15. Marine Enzymes and Microorganisms for Bioethanol Production.

    PubMed

    Swain, M R; Natarajan, V; Krishnan, C

    2017-01-01

    Bioethanol is a potential alternative fuel to fossil fuels. Bioethanol as a fuel has several economic and environmental benefits. Though bioethanol is produced using starch and sugarcane juice, these materials are in conflict with food availability. To avoid food-fuel conflict, the second-generation bioethanol production by utilizing nonfood lignocellulosic materials has been extensively investigated. However, due to the complexity of lignocellulose architecture, the process is complicated and not economically competitive. The cultivation of lignocellulosic energy crops indirectly affects the food supplies by extensive land use. Marine algae have attracted attention to replace the lignocellulosic feedstock for bioethanol production, since the algae grow fast, do not use land, avoid food-fuel conflict and have several varieties to suit the cultivation environment. The composition of algae is not as complex as lignocellulose due to the absence of lignin, which renders easy hydrolysis of polysaccharides to fermentable sugars. Marine organisms also produce cold-active enzymes for hydrolysis of starch, cellulose, and algal polysaccharides, which can be employed in bioethanol process. Marine microoorganisms are also capable of fermenting sugars under high salt environment. Therefore, marine biocatalysts are promising for development of efficient processes for bioethanol production.

  16. Nutrient profile and availability of co-products from bioethanol processing.

    PubMed

    Azarfar, A; Jonker, A; Hettiarachchi-Gamage, I K; Yu, P

    2012-06-01

    Bioethanol production in North America has led to the production of considerable quantities of different co-products. Variation in nutrient profiles as well as nutrient availability among these co-products may lead to the formulation of imbalanced diets that may adversely affect animal performance. This study aimed to compare three types of dried distiller's grains with solubles [100% wheat DDGS (WDDGS); DDGS blend1 (BDDGS1, corn to wheat ratio 30:70); DDGS blend2 (BDDGS2, corn to wheat ratio 50:50)] and their different batches within DDGS type with regard to: (i) protein and carbohydrate sub-fractions based on Cornell Net Carbohydrate and Protein System (CNCPS); (ii) calculated energy values; and (iii) rumen degradation of dry matter (DDM), organic matter (DOM), crude protein (DCP), neutral detergent fibre (DNDF) and starch (Dstarch) at 36 and 72 h of ruminal incubations. Wheat DDGS had a lower intermediately (PB2, 136.4 vs. 187.4 g/kg DM) and a higher slowly degradable true protein (PB3, 142.2 vs.105.3 g/kg DM) than BDDGS1, but similar to those of BDDGS2. Sugar (CA4) was higher, whereas starch (PB1) and digestible fibre (PB3) were lower in WDDGS than in BDDGS1 and BDDGS2. All carbohydrate sub-fractions determined differed significantly between the two batches of BDDGS2. The BDDGS2 had the highest calculated energy values (TDN, DE(3×) , ME(3×) , NEL(3×) , NE(m) and NE(g) ) among the three DDGS types. The energy values were slightly different between the batches of the three DDGS types. At all incubation times, wheat DDGS had a significantly higher (p < 0.05) DDM, DOM, DCP and DNDF than both DDGS blends. Differences were observed between different batches within DDGS types with regard to in situ rumen degradation of DM, OM, CP, NDF and starch. In conclusion, differences were observed in protein and carbohydrate sub-fractions and in situ ruminal degradation of DM, OM, CP, NDF and starch among the three DDGS types and different batches within DDGS type. This

  17. Possible use of the carbohydrates present in tomato pomace and in byproducts of the supercritical carbon dioxide lycopene extraction process as biomass for bioethanol production.

    PubMed

    Lenucci, Marcello S; Durante, Miriana; Anna, Montefusco; Dalessandro, Giuseppe; Piro, Gabriella

    2013-04-17

    This study provides information about the carbohydrate present in tomato pomace (skins, seeds, and vascular tissues) as well as in the byproducts of the lycopene supercritical carbon dioxide extraction (SC-CO₂) such as tomato serum and exhausted matrix and reports their conversion into bioethanol. The pomace, constituting approximately 4% of the tomato fruit fresh weight, and the SC-CO₂-exhausted matrix were enzyme saccharified with 0.1% Driselase leading to sugar yields of ~383 and ~301 mg/g dw, respectively. Aliquots of the hydrolysates and of the serum (80% tomato sauce fw) were fermented by Saccharomyces cerevisiae . The bioethanol produced from each waste was usually >50% of the calculated theoretical amount, with the exception of the exhausted matrix hydolysate, where a sugar concentration >52.8 g/L inhibited the fermentation process. Furthermore, no differences in the chemical solubility of cell wall polysaccharides were evidenced between the SC-CO₂-lycopene extracted and unextracted matrices. The deduced glycosyl linkage composition and the calculated amount of cell wall polysaccharides remained similar in both matrices, indicating that the SC-CO₂ extraction technology does not affect their structure. Therefore, tomato wastes may well be considered as potential alternatives and low-cost feedstock for bioethanol production.

  18. Bioethanol from poplar: a commercially viable alternative to fossil fuel in the European Union.

    PubMed

    Littlewood, Jade; Guo, Miao; Boerjan, Wout; Murphy, Richard J

    2014-01-01

    The European Union has made it a strategic objective to develop its biofuels market in order to minimize greenhouse gas (GHG) emissions, to help mitigate climate change and to address energy insecurity within the transport sector. Despite targets set at national and supranational levels, lignocellulosic bioethanol production has yet to be widely commercialized in the European Union. Here, we use techno-economic modeling to compare the price of bioethanol produced from short rotation coppice (SRC) poplar feedstocks under two leading processing technologies in five European countries. Our evaluation shows that the type of processing technology and varying national costs between countries results in a wide range of bioethanol production prices (€0.275 to 0.727/l). The lowest production prices for bioethanol were found in countries that had cheap feedstock costs and high prices for renewable electricity. Taxes and other costs had a significant influence on fuel prices at the petrol station, and therefore the presence and amount of government support for bioethanol was a major factor determining the competitiveness of bioethanol with conventional fuel. In a forward-looking scenario, genetically engineering poplar with a reduced lignin content showed potential to enhance the competitiveness of bioethanol with conventional fuel by reducing overall costs by approximately 41% in four out of the five countries modeled. However, the possible wider phenotypic traits of advanced poplars needs to be fully investigated to ensure that these do not unintentionally negate the cost savings indicated. Through these evaluations, we highlight the key bottlenecks within the bioethanol supply chain from the standpoint of various stakeholders. For producers, technologies that are best suited to the specific feedstock composition and national policies should be optimized. For policymakers, support schemes that benefit emerging bioethanol producers and allow renewable fuel to be

  19. The influence of surface microstructure and chemical composition on corrosion behaviour in fuel-grade bio-ethanol of low-alloy steel modified by plasma nitro-carburizing and post-oxidizing

    NASA Astrophysics Data System (ADS)

    Boniatti, Rosiana; Bandeira, Aline L.; Crespi, Ângela E.; Aguzzoli, Cesar; Baumvol, Israel J. R.; Figueroa, Carlos A.

    2013-09-01

    The interaction of bio-ethanol on steel surfaces modified by plasma-assisted diffusion technologies is studied for the first time. The influence of surface microstructure and chemical composition on corrosion behaviour of AISI 4140 low-alloy steel in fuel-grade bio-ethanol was investigated. The steel surfaces were modified by plasma nitro-carburizing followed plasma oxidizing. X-ray diffraction, scanning electron microscopy, optical microscopy, X-ray dispersive spectroscopy, and glow-discharge optical emission spectroscopy were used to characterize the modified surface before and after immersion tests in bio-ethanol up to 77 days. The main corrosion mechanism is pit formation. The pit density and pit size were measured in order to quantify the corrosion resistance which was found to depend more strongly on microstructure and morphology of the oxide layer than on its thickness. The best corrosion protection was observed for samples post-oxidized at 480 °C and 90 min.

  20. Bioethanol production from Scenedesmus obliquus sugars: the influence of photobioreactors and culture conditions on biomass production.

    PubMed

    Miranda, J R; Passarinho, P C; Gouveia, L

    2012-10-01

    A closed-loop vertical tubular photobioreactor (PBR), specially designed to operate under conditions of scarce flat land availability and irregular solar irradiance conditions, was used to study the potential of Scenedesmus obliquus biomass/sugar production. The results obtained were compared to those from an open-raceway pond and a closed-bubble column. The influence of the type of light source and the regime (natural vs artificial and continuous vs light/dark cycles) on the growth of the microalga and the extent of the sugar accumulation was studied in both PBRs. The best type of reactor studied was a closed-loop PBR illuminated with natural light/dark cycles. In all the cases, the relationship between the nitrate depletion and the sugar accumulation was observed. The microalga Scenedesmus was cultivated for 53 days in a raceway pond (4,500 L) and accumulated a maximum sugar content of 29 % g/g. It was pre-treated for carrying out ethanol fermentation assays, and the highest ethanol concentration obtained in the hydrolysate fermented by Kluyveromyces marxianus was 11.7 g/L.

  1. Modelling the metabolic characteristics of proteins in dairy cattle from co-products of bioethanol processing: comparison of the NRC 2001 model with the DVE/OEB system.

    PubMed

    Nuez-Ortín, Waldo G; Yu, Peiqiang

    2011-02-01

    Co-products from bioethanol processing include wheat dried distillers grains with solubles (DDGS), corn DDGS, blend DDGS (e.g. wheat/corn at 70:30, 60:40 or 50:50 w/w), triticale DDGS, barley DDGS and pea DDGS. The objective of this study was to compare two systems, the DVE/OEB system versus the NRC 2001 model, in modelling the metabolic characteristics of proteins in dairy cattle from different types of co-products (DDGS) from different bioethanol processing plants. The predicted values from the NRC 2001 model were 10% higher (P < 0.05) in truly absorbable rumen-synthesised microbial protein in the small intestine, 10% lower (P < 0.05) in truly absorbed rumen-undegraded feed protein in the small intestine, 30% lower (P < 0.05) in endogenous protein and 2% lower (P < 0.05) in total truly absorbed protein in the small intestine than the predicted values from the DVE/OEB system. However, no significant difference was detected in terms of the degraded protein balance between the two models (P > 0.05). The sensitivity of the two models in detecting differences among DDGS types and between bioethanol plants was similar. The two models coincided in the superior protein value of blend DDGS as well as in the more optimal degraded protein balance (DPB) for corn DDGS. Although the differences between the DVE/OEB system and the NRC 2001 model were significant (P < 0.05) for most outputs owing to differences in some of the concepts and factors used in modelling, the correlations between total truly absorbed protein (DVE) and metabolisable protein (MP) values and between degraded protein balances (DPB(OEB) vs DPB(NRC) ) were also significant (P < 0.05). 2010 Society of Chemical Industry.

  2. Pretreatment methods for bioethanol production.

    PubMed

    Xu, Zhaoyang; Huang, Fang

    2014-09-01

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

  3. Soaking pretreatment of corn stover for bioethanol production followed by anaerobic digestion process.

    PubMed

    Zuo, Zhuang; Tian, Shen; Chen, Zebing; Li, Jia; Yang, Xiushan

    2012-08-01

    The production of ethanol and methane from corn stover (CS) was investigated in a biorefinery process. Initially, a novel soaking pretreatment (NaOH and aqueous-ammonia) for CS was developed to remove lignin, swell the biomass, and improve enzymatic digestibility. Based on the sugar yield during enzymatic hydrolysis, the optimal pretreatment conditions were 1 % NaOH+8 % NH(4)OH, 50°C, 48 h, with a solid-to-liquid ratio 1:10. The results demonstrated that soaking pretreatment removed 63.6 % lignin while reserving most of the carbohydrates. After enzymatic hydrolysis, the yields of glucose and xylose were 78.5 % and 69.3 %, respectively. The simultaneous saccharification and fermentation of pretreated CS using Pichia stipitis resulted in an ethanol concentration of 36.1 g/L, corresponding only to 63.3 % of the theoretical maximum. In order to simplify the process and reduce the capital cost, the liquid fraction of the pretreatment was used to re-soak new CS. For methane production, the re-soaked CS and the residues of SSF were anaerobically digested for 120 days. Fifteen grams CS were converted to 1.9 g of ethanol and 1337.3 mL of methane in the entire process.

  4. Antioxidant activity of lignin phenolic compounds as by-product of pretreatment process of bioethanol production from empty fruits palm bunch

    NASA Astrophysics Data System (ADS)

    Meliana, Y.; Setiawan, A. H.

    2016-02-01

    As by-product of pretreatment bioethanol production, ligno-cellulosic biomass creates an abundance of bioresidue. This work is devoted to studies the antioxidant activity of lignin that obtained from recovery process of bioethanol by-product. This by-product comes from pretreatment process of empty fruit palm bunch in acid (pH 2) and alkaline (pH 12) conditions. The samples of purified lignin were characterized by Fourier Transform Infrared (FTIR) and Particle Size Analyzer (PSA). Radical scavenging efficiency of lignin was examined by the 2,2-diphenyl-1-picrylhydrazyl (DPPH) method using quercetin as a standard. The value of IC50 showed that the lignin that was purified in acid condition (pH 2) gave the activity value in antioxidant active range (IC50 sample Lignin pH 2 = 69.41), on the other hand the lignin that was purified in alkaline condition (Lignin pH 12) did not have the activity value as an antioxidant (IC50 sample Lignin pH 12 = NA).

  5. Valorization of carob waste: Definition of a second-generation bioethanol production process.

    PubMed

    Bahry, Hajar; Pons, Agnès; Abdallah, Rawa; Pierre, Guillaume; Delattre, Cédric; Fayad, Nidal; Taha, Samir; Vial, Christophe

    2017-03-11

    The aim of this work was to develop a strategy for second-generation ethanol production from carob solid waste issued from Lebanese food industry. The pros and cons of submerged (SF) and solid-state fermentations (SSF) using S. cerevisiae on ethanol yield and productivity were compared, including the respective roles of upstream and downstream processes, such as the size reduction, or sugar and ethanol recovery processes. The design of experiments methodology was applied. Experimental results demonstrated that SSF applied to cut carob waste from carob syrup preparation was simpler to operate and more cost-effective, maintained yield and productivity (0.458g ethanol/g consumed sugar and 4.3g/(kg waste)/h) in comparison to SF (0.450g ethanol/g consumed sugar and 5.7g/(kg waste)/h), and was able to achieve ethanol production up to 155g/(kg waste) at low water demand, while SF reached only 78g/(kg waste) due to the limitations of the sugar extraction pretreatment.

  6. Optimization of hydrothermal pretreatment of lignocellulosic biomass in the bioethanol production process.

    PubMed

    Nitsos, Christos K; Matis, Konstantinos A; Triantafyllidis, Kostas S

    2013-01-01

    The natural resistance to enzymatic deconstruction exhibited by lignocellulosic materials has designated pretreatment as a key step in the biological conversion of biomass to ethanol. Hydrothermal pretreatment in pure water represents a challenging approach because it is a method with low operational costs and does not involve the use of organic solvents, difficult to handle chemicals, and "external" liquid or solid catalysts. In the present work, a systematic study has been performed to optimize the hydrothermal treatment of lignocellulosic biomass (beech wood) with the aim of maximizing the enzymatic digestibility of cellulose in the treated solids and obtaining a liquid side product that could also be utilized for the production of ethanol or valuable chemicals. Hydrothermal treatment experiments were conducted in a batch-mode, high-pressure reactor under autogeneous pressure at varying temperature (130-220 °C) and time (15-180 min) regimes, and at a liquid-to-solid ratio (LSR) of 15. The intensification of the process was expressed by the severity factor, log R(o). The major changes induced in the solid biomass were the dissolution/removal of hemicellulose to the process liquid and the partial removal and relocation of lignin on the external surface of biomass particles in the form of recondensed droplets. The above structural changes led to a 2.5-fold increase in surface area and total pore volume of the pretreated biomass solids. The enzymatic hydrolysis of cellulose to glucose increased from less than 7 wt% for the parent biomass to as high as 70 wt% for the treated solids. Maximum xylan recovery (60 wt%) in the hydrothermal process liquid was observed at about 80 wt% hemicellulose removal; this was accomplished by moderate treatment severities (log R(o)=3.8-4.1). At higher severities (log R(o)=4.7), xylose degradation products, mainly furfural and formic acid, were the predominant chemicals formed. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGa

  7. Process development for the production of bioethanol from waste algal biomass of Gracilaria verrucosa.

    PubMed

    Shukla, Rishikesh; Kumar, Manoj; Chakraborty, Subhojit; Gupta, Rishi; Kumar, Savindra; Sahoo, Dinabandhu; Kuhad, Ramesh Chander

    2016-11-01

    The algal biomass of different species of Gracilaria were collected from coasts of Orissa and Tamil Nadu, India and characterized biochemically. Among various species, G. verrucosa was found to be better in terms of total carbohydrate content (56.65%) and hence selected for further studies. The agar was extracted from algal biomass and the residual pulp was enzymatically hydrolyzed. The optimization of algal pulp hydrolysis for various parameters revealed a maximum sugar release of 75.8mg/ml with 63% saccharification yield. The fermentation of enzymatic hydrolysate of algal pulp was optimized and 8% (v/v) inoculum size, 12h inoculum age, pH 5.0 were found to be optimum parameters for maximum ethanol concentration (27.2g/L) after 12h. The process of enzymatic hydrolysis and fermentation were successfully scaled up to 2L bioreactor scale.

  8. Impacts of Deacetylation Prior to Dilute Acid Pretreatment on the Bioethanol Process

    SciTech Connect

    Chen, X.; Shekiro, J.; Franden, M. A.; Wang, W.; Johnson, D. K.; Zhang, M.; Kuhn, E.; Tucker, M. P.

    2011-12-01

    Dilute acid pretreatment is a promising pretreatment technology for the biochemical production of ethanol from lignocellulosic biomass. During dilute acid pretreatment, xylan depolymerizes to form soluble xylose monomers and oligomers. Because the xylan found in nature is highly acetylated, the formation of xylose monomers requires two steps: (1) cleavage of the xylosidic bonds, and (2) cleavage of covalently bonded acetyl ester groups. Results: In this study, we show that the latter may be the rate limiting step for xylose monomer formation. Furthermore, acetyl groups are also found to be a cause of biomass recalcitrance and hydrolyzate toxicity. While the removal of acetyl groups from native corn stover by alkaline de-esterification prior to pretreatment improves overall process yields, the exact impact is highly dependent on the corn stover variety in use. Xylose monomer yields in pretreatment generally increases by greater than 10%. Compared to pretreated corn stover controls, the deacetylated corn stover feedstock is approximately 20% more digestible after pretreatment. Finally, by lowering hydrolyzate toxicity, xylose utilization and ethanol yields are further improved during fermentation by roughly 10% and 7%, respectively. In this study, several varieties of corn stover lots were investigated to test the robustness of the deacetylation-pretreatment-saccharification-fermentation process. Conclusions: Deacetylation shows significant improvement on glucose and xylose yields during pretreatment and enzymatic hydrolysis, but it also reduces hydrolyzate toxicity during fermentation, thereby improving ethanol yields and titer. The magnitude of effect is dependent on the selected corn stover variety, with several varieties achieving improvements of greater than 10% xylose yield in pretreatment, 20% glucose yield in low solids enzymatic hydrolysis and 7% overall ethanol yield.

  9. The impacts of deacetylation prior to dilute acid pretreatment on the bioethanol process

    PubMed Central

    2012-01-01

    Background Dilute acid pretreatment is a promising pretreatment technology for the biochemical production of ethanol from lignocellulosic biomass. During dilute acid pretreatment, xylan depolymerizes to form soluble xylose monomers and oligomers. Because the xylan found in nature is highly acetylated, the formation of xylose monomers requires two steps: 1) cleavage of the xylosidic bonds, and 2) cleavage of covalently bonded acetyl ester groups. Results In this study, we show that the latter may be the rate limiting step for xylose monomer formation. Furthermore, acetyl groups are also found to be a cause of biomass recalcitrance and hydrolyzate toxicity. While the removal of acetyl groups from native corn stover by alkaline de-esterification prior to pretreatment improves overall process yields, the exact impact is highly dependent on the corn stover variety in use. Xylose monomer yields in pretreatment generally increases by greater than 10%. Compared to pretreated corn stover controls, the deacetylated corn stover feedstock is approximately 20% more digestible after pretreatment. Finally, by lowering hydrolyzate toxicity, xylose utilization and ethanol yields are further improved during fermentation by roughly 10% and 7%, respectively. In this study, several varieties of corn stover lots were investigated to test the robustness of the deacetylation-pretreatment-saccharification-fermentation process. Conclusions Deacetylation shows significant improvement on glucose and xylose yields during pretreatment and enzymatic hydrolysis, but it also reduces hydrolyzate toxicity during fermentation, thereby improving ethanol yields and titer. The magnitude of effect is dependent on the selected corn stover variety, with several varieties achieving improvements of greater than 10% xylose yield in pretreatment, 20% glucose yield in low solids enzymatic hydrolysis and 7% overall ethanol yield. PMID:22369467

  10. Low grade bioethanol for fuel mixing on gasoline engine using distillation process

    NASA Astrophysics Data System (ADS)

    Abikusna, Setia; Sugiarto, Bambang; Suntoro, Dedi; Azami

    2017-03-01

    Utilization of renewable energy in Indonesia is still low, compared to 34% oil, 20% coal and 20% gas, utilization of energy sources for water 3%, geothermal 1%, 2% biofuels, and biomass 20%. Whereas renewable energy sources dwindling due to the increasing consumption of gasoline as a fuel. It makes us have to look for alternative renewable energy, one of which is bio ethanol. Several studies on the use of ethanol was done to the researchers. Our studies using low grade bio ethanol which begins with the disitillation independently utilize flue gas heat at compact distillator, produces high grade bio ethanol and ready to be mixed with gasoline. Stages of our study is the compact distillator design of the motor dynamic continued with good performance and emission testing and ethanol distilled. Some improvement is made is through the flue gas heat control mechanism in compact distillator using gate valve, at low, medium, and high speed engine. Compact distillator used is kind of a batch distillation column. Column design process using the shortcut method, then carried the tray design to determine the overall geometry. The distillation is done by comparing the separator with a tray of different distances. As well as by varying the volume of the feed and ethanol levels that will feed distilled. In this study, we analyzed the mixing of ethanol through variation between main jet and pilot jet in the carburetor separately interchangeably with gasoline. And finally mixing mechanism bio ethanol with gasoline improved with fuel mixer for performance.

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

    PubMed

    Mabee, W E; Saddler, J N

    2010-07-01

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

  12. Phenotypic characterisation of Saccharomyces spp. yeast for tolerance to stresses encountered during fermentation of lignocellulosic residues to produce bioethanol

    PubMed Central

    2014-01-01

    Background During industrial fermentation of lignocellulose residues to produce bioethanol, microorganisms are exposed to a number of factors that influence productivity. These include inhibitory compounds produced by the pre-treatment processes required to release constituent carbohydrates from biomass feed-stocks and during fermentation, exposure of the organisms to stressful conditions. In addition, for lignocellulosic bioethanol production, conversion of both pentose and hexose sugars is a pre-requisite for fermentative organisms for efficient and complete conversion. All these factors are important to maximise industrial efficiency, productivity and profit margins in order to make second-generation bioethanol an economically viable alternative to fossil fuels for future transport needs. Results The aim of the current study was to assess Saccharomyces yeasts for their capacity to tolerate osmotic, temperature and ethanol stresses and inhibitors that might typically be released during steam explosion of wheat straw. Phenotypic microarray analysis was used to measure tolerance as a function of growth and metabolic activity. Saccharomyces strains analysed in this study displayed natural variation to each stress condition common in bioethanol fermentations. In addition, many strains displayed tolerance to more than one stress, such as inhibitor tolerance combined with fermentation stresses. Conclusions Our results suggest that this study could identify a potential candidate strain or strains for efficient second generation bioethanol production. Knowledge of the Saccharomyces spp. strains grown in these conditions will aid the development of breeding programmes in order to generate more efficient strains for industrial fermentations. PMID:24670111

  13. Design of nanocatalysts for green hydrogen production from bioethanol.

    PubMed

    Bion, Nicolas; Duprez, Daniel; Epron, Florence

    2012-01-09

    Bioethanol is an interesting feedstock that may be used for hydrogen production by steam or autothermal reforming. However, the impurities (heavy alcohols, esters, acids, N compounds) contained in the raw feedstock require a costly purification, as they have a dramatic impact on catalyst activity and stability. Thus, a method that can utilize the raw feedstock without severe degradation of the catalyst would be desirable. In this Minireview, the composition of bioethanol from first and second generation biomass, the reactions involved in the catalytic ethanol steam reforming process and the design of catalysts adapted for hydrogen production from a real bioethanol feed are surveyed.

  14. Utilization of by-products derived from bioethanol production process for cost-effective production of lactic acid.

    PubMed

    Moon, Se-Kwon; Wee, Young-Jung; Choi, Gi-Wook

    2014-10-01

    The by-products of bioethanol production such as thin stillage (TS) and condensed distillers solubles (CDS) were used as a potential nitrogen source for economical production of lactic acid. The effect of those by-products and their concentrations on lactic acid fermentation were investigated using Lactobacillus paracasei CHB2121. Approximately, 6.7 g/L of yeast extract at a carbon source to nitrogen source ratio of 15 was required to produce 90 g/L of lactic acid in the medium containing 100 g/L of glucose. Batch fermentation of TS medium resulted in 90 g/L of lactic acid after 48 h, and the medium containing 10 % CDS resulted in 95 g/L of lactic acid after 44 h. Therefore, TS and CDS could be considered as potential alternative fermentation medium for the economical production of lactic acid. Furthermore, lactic acid fermentation was performed using only cassava and CDS for commercial production of lactic acid. The volumetric productivity of lactic acid [2.94 g/(L·h)] was 37 % higher than the productivity obtained from the medium with glucose and CDS.

  15. Scientific challenges of bioethanol production in Brazil.

    PubMed

    Amorim, Henrique V; Lopes, Mário Lucio; de Castro Oliveira, Juliana Velasco; Buckeridge, Marcos S; Goldman, Gustavo Henrique

    2011-09-01

    Bioethanol (fuel alcohol) has been produced by industrial alcoholic fermentation processes in Brazil since the beginning of the twentieth century. Currently, 432 mills and distilleries crush about 625 million tons of sugarcane per crop, producing about 27 billion liters of ethanol and 38.7 million tons of sugar. The production of bioethanol from sugarcane represents a major large-scale technology capable of producing biofuel efficiently and economically, providing viable substitutes to gasoline. The combination of immobilization of CO₂ by sugarcane crops by photosynthesis into biomass together with alcoholic fermentation of this biomass has allowed production of a clean and high-quality liquid fuel that contains 93% of the original energy found in sugar. Over the last 30 years, several innovations have been introduced to Brazilian alcohol distilleries resulting in the improvement of plant efficiency and economic competitiveness. Currently, the main scientific challenges are to develop new technologies for bioethanol production from first and second generation feedstocks that exhibit positive energy balances and appropriately meet environmental sustainability criteria. This review focuses on these aspects and provides special emphasis on the selection of new yeast strains, genetic breeding, and recombinant DNA technology, as applied to bioethanol production processes.

  16. Bioethanol produced from Moringa oleifera seeds husk

    NASA Astrophysics Data System (ADS)

    Ali, E. N.; Kemat, S. Z.

    2017-06-01

    This paper presents the potential of bioethanol production from Moringa oleifera seeds husk which contains lignocellulosic through Simultaneous Saccharification and Fermentation (SSF) process by using Saccharomyces cerevisiae. This paper investigates the parameters which produce optimum bioethanol yield. The husk was hydrolyzed using NaOH and fermented using Saccharomyces cerevisiae yeast. Batch fermentation was performed with different yeast dosage of 1, 3, and 5 g/L, pH value was 4.5, 5.0 and 5.5, and fermentation time of 3, 6, 9 and 12 hours. The temperature of fermentation process in incubator shaker is kept constant at 32ºC. The samples are then filtered using a 0.20 μm nylon filter syringe. The yield of bioethanol produced was analysed using High Performance Liquid Chromatography (HPLC). The results showed that the highest yield of 29.69 g/L was obtained at 3 hours of fermentation time at pH of 4.5 and using 1g/L yeast. This research work showed that Moringa oleifera seeds husk can be considered to produce bioethanol.

  17. Bioethanol from Lignocellulosic Biomass: Current Findings Determine Research Priorities

    PubMed Central

    Kang, Qian; Appels, Lise; Tan, Tianwei

    2014-01-01

    “Second generation” bioethanol, with lignocellulose material as feedstock, is a promising alternative for first generation bioethanol. This paper provides an overview of the current status and reveals the bottlenecks that hamper its implementation. The current literature specifies a conversion of biomass to bioethanol of 30 to ~50% only. Novel processes increase the conversion yield to about 92% of the theoretical yield. New combined processes reduce both the number of operational steps and the production of inhibitors. Recent advances in genetically engineered microorganisms are promising for higher alcohol tolerance and conversion efficiency. By combining advanced systems and by intensive additional research to eliminate current bottlenecks, second generation bioethanol could surpass the traditional first generation processes. PMID:25614881

  18. Production of bioethanol and biodiesel using instant noodle waste.

    PubMed

    Yang, Xiaoguang; Lee, Ja Hyun; Yoo, Hah Young; Shin, Hyun Yong; Thapa, Laxmi Prasad; Park, Chulhwan; Kim, Seung Wook

    2014-08-01

    Instant noodle manufacturing waste was used as feedstock to convert it into two products, bioethanol and biodiesel. The raw material was pretreated to separate it into two potential feedstocks, starch residues and palm oil, for conversion to bioethanol and biodiesel, respectively. For the production of bioethanol, starch residues were converted into glucose by α-amylase and glucoamylase. To investigate the saccharification process of the pretreated starch residues, the optimal pretreatment conditions were determined. The bioethanol conversion reached 98.5 % of the theoretical maximum by Saccharomyces cerevisiae K35 fermentation after saccharification under optimized pretreatment conditions. Moreover, palm oil, isolated from the instant noodle waste, was converted into valuable biodiesel by use of immobilized lipase (Novozym 435). The effects of four categories of alcohol, oil-to-methanol ratio, reaction time, lipase concentration and water content on the conversion process were investigated. The maximum biodiesel conversion was 95.4 %.

  19. Optimized utilization of the co-products from bioethanol processing and oat grain: effect of blending on biochemical, biodegradation, and nutritional profiles.

    PubMed

    Damiran, Daalkhaijav; Zhang, Xuewei; Yu, Peiqiang

    2013-11-27

    The objective of this study was to (1) optimize the utilization of wheat-based dried distillers grains with soluble (wDDGS) by blending with oat ( Avena sativa L.) grain as an alternative feed for beef cattle when the barley price is high and (2) investigate the effect of blending on biochemical, biodegradation, and nutritional profiles. Oat grains were blended with wDDGS produced in western Canada at different levels (4:0, 3:1, 2:2, and 1:3 on %DM basis in two batches, denoted O0, O25, O50, and O75, respectively). The study revealed that increasing the wDDGS resulted in increasing most nutrient contents linearly (P < 0.05) except for starch and cell wall materials, which were linearly decreased (from 43.6 to 12.0% and from 34.5 to 29.1% of DM for starch and NDF, respectively). When wDDGS was increased in the blend/mixture, intestinally absorbable protein and degradable balance of protein increased (P < 0.05). Overall, through blending or combining with the cereal grain, the co-products from bioethanol processing could be optimally utilized. The best combination of oat to wDDGS ratio was 75% to 25%.

  20. The Peer Influence Process.

    ERIC Educational Resources Information Center

    Hallinan, Maureen T.

    1981-01-01

    Outlining a conceptual scheme specifying how peer influences mediate the effects of organizational characteristics of schools on student outcomes, with social psychological theories of interpersonal attraction and influence as the basis for the outline, is the aim of this paper. Selection of peers and influence of peers is outlined. (CE)

  1. Effect of xylanase, urea, Tween and Triton additives on bioethanol production of corn stover

    NASA Astrophysics Data System (ADS)

    Xin, Xiu; Lu, Jie; Yang, Rui-Feng; Song, Wen-jing; Li, Hai-ming; Wang, Hai-song; Zhou, Jing-hui

    2017-03-01

    Corn stover is a potential source of renewable biomass for conversion to bioethanol. Fed-batch semi-simultaneous saccharifcation and fermentation (S-SSF) of corn stover pretreated by liquid hot water (LHW) was investigated. The present study aimed to confirm the influence of xylanase, urea, Tween and Triton additives on bioethanol. Results show that the positive effect of xylanase, urea, Tween was observed. High ethanol concentration requires the addition of xylanase in the stage of saccharification. The optimal amount of xylanase was 0.2 g/g biomass and addition of Triton (Triton X-100) increases the effect of xylanase. Urea has a promotion effect on the whole fermentation process.When adding 0.1% urea in the fermentation stage,the best promoting rate is 24.2%. In the longitudinal comparison of the Tween series, under the same experimental conditions, the promoting effect of Tween series: Tween 40 > Tween 80 > Tween 20 > Tween 60.

  2. Saccharification and liquefaction of cassava starch: an alternative source for the production of bioethanol using amylolytic enzymes by double fermentation process.

    PubMed

    Pervez, Sidra; Aman, Afsheen; Iqbal, Samina; Siddiqui, Nadir Naveed; Ul Qader, Shah Ali

    2014-05-29

    Cassava starch is considered as a potential source for the commercial production of bioethanol because of its availability and low market price. It can be used as a basic source to support large-scale biological production of bioethanol using microbial amylases. With the progression and advancement in enzymology, starch liquefying and saccharifying enzymes are preferred for the conversion of complex starch polymer into various valuable metabolites. These hydrolytic enzymes can selectively cleave the internal linkages of starch molecule to produce free glucose which can be utilized to produce bioethanol by microbial fermentation. In the present study, several filamentous fungi were screened for production of amylases and among them Aspergillus fumigatus KIBGE-IB33 was selected based on maximum enzyme yield. Maximum α-amylase, amyloglucosidase and glucose formation was achieved after 03 days of fermentation using cassava starch. After salt precipitation, fold purification of α-amylase and amyloglucosidase increased up to 4.1 and 4.2 times with specific activity of 9.2 kUmg⁻¹ and 393 kUmg⁻¹, respectively. Concentrated amylolytic enzyme mixture was incorporated in cassava starch slurry to give maximum glucose formation (40.0 gL⁻¹), which was further fermented using Saccharomyces cerevisiae into bioethanol with 84.0% yield. The distillate originated after recovery of bioethanol gave 53.0% yield. An improved and effective dual enzymatic starch degradation method is designed for the production of bioethanol using cassava starch. The technique developed is more profitable due to its fast liquefaction and saccharification approach that was employed for the formation of glucose and ultimately resulted in higher yields of alcohol production.

  3. Saccharification and liquefaction of cassava starch: an alternative source for the production of bioethanol using amylolytic enzymes by double fermentation process

    PubMed Central

    2014-01-01

    Background Cassava starch is considered as a potential source for the commercial production of bioethanol because of its availability and low market price. It can be used as a basic source to support large-scale biological production of bioethanol using microbial amylases. With the progression and advancement in enzymology, starch liquefying and saccharifying enzymes are preferred for the conversion of complex starch polymer into various valuable metabolites. These hydrolytic enzymes can selectively cleave the internal linkages of starch molecule to produce free glucose which can be utilized to produce bioethanol by microbial fermentation. Results In the present study, several filamentous fungi were screened for production of amylases and among them Aspergillus fumigatus KIBGE-IB33 was selected based on maximum enzyme yield. Maximum α-amylase, amyloglucosidase and glucose formation was achieved after 03 days of fermentation using cassava starch. After salt precipitation, fold purification of α-amylase and amyloglucosidase increased up to 4.1 and 4.2 times with specific activity of 9.2 kUmg-1 and 393 kUmg-1, respectively. Concentrated amylolytic enzyme mixture was incorporated in cassava starch slurry to give maximum glucose formation (40.0 gL-1), which was further fermented using Saccharomyces cerevisiae into bioethanol with 84.0% yield. The distillate originated after recovery of bioethanol gave 53.0% yield. Conclusion An improved and effective dual enzymatic starch degradation method is designed for the production of bioethanol using cassava starch. The technique developed is more profitable due to its fast liquefaction and saccharification approach that was employed for the formation of glucose and ultimately resulted in higher yields of alcohol production. PMID:24885587

  4. Bioethanol production from fermentable sugar juice.

    PubMed

    Zabed, Hossain; Faruq, Golam; Sahu, Jaya Narayan; Azirun, Mohd Sofian; Hashim, Rosli; Boyce, Amru Nasrulhaq

    2014-01-01

    Bioethanol production from renewable sources to be used in transportation is now an increasing demand worldwide due to continuous depletion of fossil fuels, economic and political crises, and growing concern on environmental safety. Mainly, three types of raw materials, that is, sugar juice, starchy crops, and lignocellulosic materials, are being used for this purpose. This paper will investigate ethanol production from free sugar containing juices obtained from some energy crops such as sugarcane, sugar beet, and sweet sorghum that are the most attractive choice because of their cost-effectiveness and feasibility to use. Three types of fermentation process (batch, fed-batch, and continuous) are employed in ethanol production from these sugar juices. The most common microorganism used in fermentation from its history is the yeast, especially, Saccharomyces cerevisiae, though the bacterial species Zymomonas mobilis is also potentially used nowadays for this purpose. A number of factors related to the fermentation greatly influences the process and their optimization is the key point for efficient ethanol production from these feedstocks.

  5. Bioethanol Production from Fermentable Sugar Juice

    PubMed Central

    Zabed, Hossain; Faruq, Golam; Sahu, Jaya Narayan; Azirun, Mohd Sofian; Hashim, Rosli; Nasrulhaq Boyce, Amru

    2014-01-01

    Bioethanol production from renewable sources to be used in transportation is now an increasing demand worldwide due to continuous depletion of fossil fuels, economic and political crises, and growing concern on environmental safety. Mainly, three types of raw materials, that is, sugar juice, starchy crops, and lignocellulosic materials, are being used for this purpose. This paper will investigate ethanol production from free sugar containing juices obtained from some energy crops such as sugarcane, sugar beet, and sweet sorghum that are the most attractive choice because of their cost-effectiveness and feasibility to use. Three types of fermentation process (batch, fed-batch, and continuous) are employed in ethanol production from these sugar juices. The most common microorganism used in fermentation from its history is the yeast, especially, Saccharomyces cerevisiae, though the bacterial species Zymomonas mobilis is also potentially used nowadays for this purpose. A number of factors related to the fermentation greatly influences the process and their optimization is the key point for efficient ethanol production from these feedstocks. PMID:24715820

  6. Bioethanol Fuel Production Concept Study: Topline Report

    SciTech Connect

    Marketing Horizons, Inc.

    2001-11-19

    The DOE is in the process of developing technologies for converting plant matter other than feed stock, e.g., corn stover, into biofuels. The goal of this research project was to determine what the farming community thinks of ethanol as a fuel source, and specifically what they think of bioethanol produced from corn stover. This project also assessed the image of the DOE and the biofuels program and determined the perceived barriers to ethanol-from-stover production.

  7. Bioethanol production from Ficus religiosa leaves using microwave irradiation.

    PubMed

    Klein, Miri; Griess, Ofir; Pulidindi, Indra Neel; Perkas, Nina; Gedanken, Aharon

    2016-07-15

    A microwave assisted feasible process for the production of bioethanol from Ficus religiosa leaves was developed. Under the process conditions (8 min. microwave irradiation, 1 M HCl), 10.1 wt% glucose yield was obtained from the leaves. Microwave based hydrolysis process yielded higher glucose content (10.1 wt%) compared to the conventional hydrothermal process (4.1 wt%). Upon fermentation of the hydrolysate using Baker's yeast, 3 wt% (dry wt. basis) of bioethanol was produced. Copyright © 2016 Elsevier Ltd. All rights reserved.

  8. Lignocellulosic agriculture wastes as biomass feedstocks for second-generation bioethanol production: concepts and recent developments.

    PubMed

    Saini, Jitendra Kumar; Saini, Reetu; Tewari, Lakshmi

    2015-08-01

    Production of liquid biofuels, such as bioethanol, has been advocated as a sustainable option to tackle the problems associated with rising crude oil prices, global warming and diminishing petroleum reserves. Second-generation bioethanol is produced from lignocellulosic feedstock by its saccharification, followed by microbial fermentation and product recovery. Agricultural residues generated as wastes during or after processing of agricultural crops are one of such renewable and lignocellulose-rich biomass resources available in huge amounts for bioethanol production. These agricultural residues are converted to bioethanol in several steps which are described here. This review enlightens various steps involved in production of the second-generation bioethanol. Mechanisms and recent advances in pretreatment, cellulases production and second-generation ethanol production processes are described here.

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

    PubMed

    Boluda-Aguilar, María; García-Vidal, Lidia; González-Castañeda, Fayiny Del Pilar; López-Gómez, Antonio

    2010-05-01

    The mandarin (Citrus reticulata L.) citrus peel wastes (MCPW) were studied for bioethanol production, obtaining also as co-products: d-limonene, galacturonic acid, and citrus pulp pellets (CPP). The steam explosion pretreatment was analysed at pilot plant level to decrease the hydrolytic enzymes requirements and to separate and recover the d-limonene. The effect of steam explosion on MCPW lignocellulosic composition was analyzed by means thermogravimetric analysis. The d-limonene contents and their influence on ethanol production have been also studied, while concentration of sugars, galacturonic acid and ethanol have been analysed to measure the saccharification and fermentation (HF and SSF) processes efficiency obtained by MCPW steam explosion pretreatment. Ethanol contents of 50-60L/1000kg raw MCPW can be obtained and CPP yields can be regulated by means the control of enzymes dose and the steam explosion pretreatment which can significantly reduce the enzymes requirements. Copyright 2009 Elsevier Ltd. All rights reserved.

  10. Dynamic modeling and analyses of simultaneous saccharification and fermentation process to produce bio-ethanol from rice straw.

    PubMed

    Ko, Jordon; Su, Wen-Jun; Chien, I-Lung; Chang, Der-Ming; Chou, Sheng-Hsin; Zhan, Rui-Yu

    2010-02-01

    The rice straw, an agricultural waste from Asians' main provision, was collected as feedstock to convert cellulose into ethanol through the enzymatic hydrolysis and followed by the fermentation process. When the two process steps are performed sequentially, it is referred to as separate hydrolysis and fermentation (SHF). The steps can also be performed simultaneously, i.e., simultaneous saccharification and fermentation (SSF). In this research, the kinetic model parameters of the cellulose saccharification process step using the rice straw as feedstock is obtained from real experimental data of cellulase hydrolysis. Furthermore, this model can be combined with a fermentation model at high glucose and ethanol concentrations to form a SSF model. The fermentation model is based on cybernetic approach from a paper in the literature with an extension of including both the glucose and ethanol inhibition terms to approach more to the actual plants. Dynamic effects of the operating variables in the enzymatic hydrolysis and the fermentation models will be analyzed. The operation of the SSF process will be compared to the SHF process. It is shown that the SSF process is better in reducing the processing time when the product (ethanol) concentration is high. The means to improve the productivity of the overall SSF process, by properly using aeration during the batch operation will also be discussed.

  11. Proteins for breaking barriers in lignocellulosic bioethanol production.

    PubMed

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

    2015-01-01

    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.

  12. Dry-grind processing using amylase corn and superior yeast to reduce the exogenous enzyme requirements in bioethanol production.

    PubMed

    Kumar, Deepak; Singh, Vijay

    2016-01-01

    Conventional corn dry-grind ethanol production process requires exogenous alpha and glucoamylases enzymes to breakdown starch into glucose, which is fermented to ethanol by yeast. This study evaluates the potential use of new genetically engineered corn and yeast, which can eliminate or minimize the use of these external enzymes, improve the economics and process efficiencies, and simplify the process. An approach of in situ ethanol removal during fermentation was also investigated for its potential to improve the efficiency of high-solid fermentation, which can significantly reduce the downstream ethanol and co-product recovery cost. The fermentation of amylase corn (producing endogenous α-amylase) using conventional yeast and no addition of exogenous α-amylase resulted in ethanol concentration of 4.1 % higher compared to control treatment (conventional corn using exogenous α-amylase). Conventional corn processed with exogenous α-amylase and superior yeast (producing glucoamylase or GA) with no exogenous glucoamylase addition resulted in ethanol concentration similar to control treatment (conventional yeast with exogenous glucoamylase addition). Combination of amylase corn and superior yeast required only 25 % of recommended glucoamylase dose to complete fermentation and achieve ethanol concentration and yield similar to control treatment (conventional corn with exogenous α-amylase, conventional yeast with exogenous glucoamylase). Use of superior yeast with 50 % GA addition resulted in similar increases in yield for conventional or amylase corn of approximately 7 % compared to that of control treatment. Combination of amylase corn, superior yeast, and in situ ethanol removal resulted in a process that allowed complete fermentation of 40 % slurry solids with only 50 % of exogenous GA enzyme requirements and 64.6 % higher ethanol yield compared to that of conventional process. Use of amylase corn and superior yeast in the dry-grind processing industry

  13. Conversion of Extracted Oil Cake Fibers into Bioethanol Including DDGS, Canola, Sunflower, Seasame, Soy, and Peanut for Integrated Biodiesel Processing

    USDA-ARS?s Scientific Manuscript database

    We have come up with a novel integrated approach where biodiesel processing can be potentially done in-house by producing ethanol from edible oilseeds after hexane extraction to remove residual oil. In addition, we have demonstrated how ethanol could be manufactured from widely available oil cakes ...

  14. Molecular spectroscopic investigation on fractionation-induced changes on biomacromolecule of co-products from bioethanol processing to explore protein metabolism in ruminants.

    PubMed

    Zhang, Xuewei; Yan, Xiaogang; Beltranena, Eduardo; Yu, Peiqiang

    2014-03-25

    Fractionation processing is an efficient technology which is capable to redesign/redevelop a new food or feed product with a specified chemical and nutrient profile. This processing technique was able to produce four different fractions (called "A", "B", "C", "D" fractions/treatments) with different nutrient profile form a co-product of bioethanol processing [wheat dried distillers grains with soluble (DDGS)]. To date, there is no study on the effect of fractionation processing on inherent molecular structure of different fractions and how the processing-induced structural change affect the metabolic characteristics of protein and nutrient availability. The objectives of this experiment were to: (1) investigate the effect of fractionation processing on changes of protein functional groups (amide I, amide II, and their ratio) and molecular structure (modeled α-helix, β-sheet, and their ratio), and (2) study the relationship between the fractionation processing-induced changes of protein molecular structure and nutrients availability as well as the metabolic characteristics of protein. The hypothesis of this study was that the fractionation processing changes the molecular structure and such changes affect the metabolic characteristics of protein. The protein molecular structure spectral profile of the fractions A, B, C and D were identified by Fourier-transform infrared attenuated total reflection spectroscopy (FT/IR-ATR). The results showed that the fractionation processing significantly affected the protein molecular spectral profiles. The differences in amide I to amide II peak area and height ratios were strongly significant (P<0.01) among the treatment fractions, ranging from 4.98 to 6.33 and 3.28 to 4.00, respectively. The difference in the modeled protein α-helix to β-sheet ratio was also strongly significant (P<0.01) among the treatment fractions. Multivariate molecular spectral analysis with cluster (CLA) and principal component analyses (PCA) showed

  15. Molecular spectroscopic investigation on fractionation-induced changes on biomacromolecule of co-products from bioethanol processing to explore protein metabolism in ruminants

    NASA Astrophysics Data System (ADS)

    Zhang, Xuewei; Yan, Xiaogang; Beltranena, Eduardo; Yu, Peiqiang

    2014-03-01

    Fractionation processing is an efficient technology which is capable to redesign/redevelop a new food or feed product with a specified chemical and nutrient profile. This processing technique was able to produce four different fractions (called "A", "B", "C", "D" fractions/treatments) with different nutrient profile form a co-product of bioethanol processing [wheat dried distillers grains with soluble (DDGS)]. To date, there is no study on the effect of fractionation processing on inherent molecular structure of different fractions and how the processing-induced structural change affect the metabolic characteristics of protein and nutrient availability. The objectives of this experiment were to: (1) investigate the effect of fractionation processing on changes of protein functional groups (amide I, amide II, and their ratio) and molecular structure (modeled α-helix, β-sheet, and their ratio), and (2) study the relationship between the fractionation processing-induced changes of protein molecular structure and nutrients availability as well as the metabolic characteristics of protein. The hypothesis of this study was that the fractionation processing changes the molecular structure and such changes affect the metabolic characteristics of protein. The protein molecular structure spectral profile of the fractions A, B, C and D were identified by Fourier-transform infrared attenuated total reflection spectroscopy (FT/IR-ATR). The results showed that the fractionation processing significantly affected the protein molecular spectral profiles. The differences in amide I to amide II peak area and height ratios were strongly significant (P < 0.01) among the treatment fractions, ranging from 4.98 to 6.33 and 3.28 to 4.00, respectively. The difference in the modeled protein α-helix to β-sheet ratio was also strongly significant (P < 0.01) among the treatment fractions. Multivariate molecular spectral analysis with cluster (CLA) and principal component analyses (PCA

  16. Study of flocculent yeast performance in tower reactors for bioethanol production in a continuous fermentation process with no cell recycling.

    PubMed

    Andrietta, Sílvio Roberto; Steckelberg, Cláudia; Andrietta, Maria da Graça Stupiello

    2008-05-01

    The purpose of this study was to assess the retention ability of 12 different Saccharomyces sp. yeast strains with flocculent characteristics when inoculated in a continuous ethanol fermentation process. The system was comprised of two reactors connected in series with no cell recycling. The feeding substrate used was a synthetic medium containing glucose. The parameters assessed were total reducing sugars of the feeding substrate, total reducing sugars and ethanol at the outlet of the first and second reactors and quantification and classification of yeast population in the two reactors. The system reached yield levels of 83.53% of theoretical yield with a maximum total reducing sugars conversion of 92.68%. The conversion in this system was lower than expected. The dominant yeast in the process in both reactors, contrary to expectation, was the Saccharomyces CP6 strain which was unable to form pellets in spite of its flocculate growth.

  17. Measurement of sucrose and ethanol concentrations in process streams and effluents of sugarcane bioethanol industry by optical fiber sensor

    NASA Astrophysics Data System (ADS)

    Fujiwara, Eric; Ono, Eduardo; Manfrim, Tarcio P.; Santos, Juliana S.; Suzuki, Carlos K.

    2011-05-01

    The measurement of process streams and effluents from sugar-ethanol industry by using optical fiber sensor based on Fresnel reflection principle is reported. Firstly, binary sucrose-water and ethanol-water solutions were measured in order to determine the calibration curves. Secondly, the co-products from various processing stages were analyzed in order to identify the sucrose or ethanol concentration. The absolute error was calculated by comparison between the nominal concentration values obtained by plant laboratory analysis and the sensor response, yielding errors <= 5 wt% and <= 5 vol% for sucrose and ethanol content, respectively. The fiber sensor provided reliable results even for samples with more complex compositions than pure sucrose or ethanol solutions, with perspectives of application on the several stages of the plant facility.

  18. The Emergence and Challenging Growth of the Bio-Ethanol Innovation System in Taiwan (1949-2015).

    PubMed

    Chung, Chao-Chen; Yang, Siang-Cing

    2016-02-19

    This study explores the bio-ethanol innovation system in Taiwan from the perspective of a technology innovation system (TIS). Taiwan is a newly industrialized country and is not currently a main producer of bio-ethanol. This study analyzes the evolution of bio-ethanol innovation system in Taiwan and places a particular emphasis on challenges that present policies face in the context of potential long-term bio-ethanol development. Through an evaluation of the consistency of the present research, technology, development and innovation (RTDI) policies as well as the influence of these policies on the functional dynamics of bio-ethanol innovation system, mechanisms prohibiting the system from flourishing are determined. It is suggested that the production of bio-ethanol in Taiwan would be achieved if the government: (1) fixes long-term targets for both domestic bio-ethanol development and emission reduction; and (2) comprehensively designs a set of interrelated RTDI policies in accordance with the functional pattern of the bio-ethanol innovation system and consistently implements these policies. If such measures were implemented, it is considered that the bio-ethanol innovation system in Taiwan would flourish.

  19. The Emergence and Challenging Growth of the Bio-Ethanol Innovation System in Taiwan (1949–2015)

    PubMed Central

    Chung, Chao-Chen; Yang, Siang-Cing

    2016-01-01

    This study explores the bio-ethanol innovation system in Taiwan from the perspective of a technology innovation system (TIS). Taiwan is a newly industrialized country and is not currently a main producer of bio-ethanol. This study analyzes the evolution of bio-ethanol innovation system in Taiwan and places a particular emphasis on challenges that present policies face in the context of potential long-term bio-ethanol development. Through an evaluation of the consistency of the present research, technology, development and innovation (RTDI) policies as well as the influence of these policies on the functional dynamics of bio-ethanol innovation system, mechanisms prohibiting the system from flourishing are determined. It is suggested that the production of bio-ethanol in Taiwan would be achieved if the government: (1) fixes long-term targets for both domestic bio-ethanol development and emission reduction; and (2) comprehensively designs a set of interrelated RTDI policies in accordance with the functional pattern of the bio-ethanol innovation system and consistently implements these policies. If such measures were implemented, it is considered that the bio-ethanol innovation system in Taiwan would flourish. PMID:26907306

  20. Microalgae for economic applications: advantages and perspectives for bioethanol

    DOE PAGES

    Simas-Rodrigues, Cíntia; Villela, Helena D. M.; Martins, Aline P.; ...

    2015-04-04

    Renewable energy has attracted significant interest in recent years as a result of sustainability, environmental impact, and socio-economic considerations. Given existing technological knowledge and based on projections relating to biofuels derived from microalgae, microalgal feedstock is considered to be one of the most important renewable energy sources potentially available for industrial production. Finally and therefore, this paper examines microalgal bioethanol technology, which converts biomass from microalgae to fuel, the chemical processes involved, and possible ways of increasing the bioethanol yield, such as abiotic factors and genetic manipulation of fermenting organisms.

  1. Microalgae for economic applications: advantages and perspectives for bioethanol

    SciTech Connect

    Simas-Rodrigues, Cíntia; Villela, Helena D. M.; Martins, Aline P.; Marques, Luiza G.; Colepicolo, Pio; Tonon, Angela P.

    2015-04-04

    Renewable energy has attracted significant interest in recent years as a result of sustainability, environmental impact, and socio-economic considerations. Given existing technological knowledge and based on projections relating to biofuels derived from microalgae, microalgal feedstock is considered to be one of the most important renewable energy sources potentially available for industrial production. Finally and therefore, this paper examines microalgal bioethanol technology, which converts biomass from microalgae to fuel, the chemical processes involved, and possible ways of increasing the bioethanol yield, such as abiotic factors and genetic manipulation of fermenting organisms.

  2. Response Surface Optimization of Bioethanol Production from Sugarcane Molasses by Pichia veronae Strain HSC-22

    PubMed Central

    Hamouda, Hamed I.; Nassar, Hussein N.; Madian, Hekmat R.; Abu Amr, Salem S.; El-Gendy, Nour Sh.

    2015-01-01

    Pichia veronae strain HSC-22 (accession number KP012558) showed a good tolerance to relatively high temperature, ethanol and sugar concentrations. Response surface optimization based on central composite design of experiments predicted the optimal values of the influencing parameters that affect the production of bioethanol from sugarcane molasses to be as follows: initial pH 5, 25% (w : v) initial molasses concentration, 35°C, 116 rpm, and 60 h. Under these optimum operating conditions the maximum bioethanol production on a batch fermenter scale was recorded as 32.32 g/L with 44% bioethanol yield. PMID:26779347

  3. Biodiesel from microalgae beats bioethanol.

    PubMed

    Chisti, Yusuf

    2008-03-01

    Renewable biofuels are needed to displace petroleum-derived transport fuels, which contribute to global warming and are of limited availability. Biodiesel and bioethanol are the two potential renewable fuels that have attracted the most attention. As demonstrated here, biodiesel and bioethanol produced from agricultural crops using existing methods cannot sustainably replace fossil-based transport fuels, but there is an alternative. Biodiesel from microalgae seems to be the only renewable biofuel that has the potential to completely displace petroleum-derived transport fuels without adversely affecting supply of food and other crop products. Most productive oil crops, such as oil palm, do not come close to microalgae in being able to sustainably provide the necessary amounts of biodiesel. Similarly, bioethanol from sugarcane is no match for microalgal biodiesel.

  4. Continuous Cellulosic Bioethanol Fermentation by Cyclic Fed-Batch Cocultivation

    PubMed Central

    Jiang, He-Long; He, Qiang; He, Zhili; Hemme, Christopher L.; Wu, Liyou

    2013-01-01

    Cocultivation of cellulolytic and saccharolytic microbial populations is a promising strategy to improve bioethanol production from the fermentation of recalcitrant cellulosic materials. Earlier studies have demonstrated the effectiveness of cocultivation in enhancing ethanolic fermentation of cellulose in batch fermentation. To further enhance process efficiency, a semicontinuous cyclic fed-batch fermentor configuration was evaluated for its potential in enhancing the efficiency of cellulose fermentation using cocultivation. Cocultures of cellulolytic Clostridium thermocellum LQRI and saccharolytic Thermoanaerobacter pseudethanolicus strain X514 were tested in the semicontinuous fermentor as a model system. Initial cellulose concentration and pH were identified as the key process parameters controlling cellulose fermentation performance in the fixed-volume cyclic fed-batch coculture system. At an initial cellulose concentration of 40 g liter−1, the concentration of ethanol produced with pH control was 4.5-fold higher than that without pH control. It was also found that efficient cellulosic bioethanol production by cocultivation was sustained in the semicontinuous configuration, with bioethanol production reaching 474 mM in 96 h with an initial cellulose concentration of 80 g liter−1 and pH controlled at 6.5 to 6.8. These results suggested the advantages of the cyclic fed-batch process for cellulosic bioethanol fermentation by the cocultures. PMID:23275517

  5. Continuous cellulosic bioethanol fermentation by cyclic fed-batch cocultivation.

    PubMed

    Jiang, He-Long; He, Qiang; He, Zhili; Hemme, Christopher L; Wu, Liyou; Zhou, Jizhong

    2013-03-01

    Cocultivation of cellulolytic and saccharolytic microbial populations is a promising strategy to improve bioethanol production from the fermentation of recalcitrant cellulosic materials. Earlier studies have demonstrated the effectiveness of cocultivation in enhancing ethanolic fermentation of cellulose in batch fermentation. To further enhance process efficiency, a semicontinuous cyclic fed-batch fermentor configuration was evaluated for its potential in enhancing the efficiency of cellulose fermentation using cocultivation. Cocultures of cellulolytic Clostridium thermocellum LQRI and saccharolytic Thermoanaerobacter pseudethanolicus strain X514 were tested in the semicontinuous fermentor as a model system. Initial cellulose concentration and pH were identified as the key process parameters controlling cellulose fermentation performance in the fixed-volume cyclic fed-batch coculture system. At an initial cellulose concentration of 40 g liter(-1), the concentration of ethanol produced with pH control was 4.5-fold higher than that without pH control. It was also found that efficient cellulosic bioethanol production by cocultivation was sustained in the semicontinuous configuration, with bioethanol production reaching 474 mM in 96 h with an initial cellulose concentration of 80 g liter(-1) and pH controlled at 6.5 to 6.8. These results suggested the advantages of the cyclic fed-batch process for cellulosic bioethanol fermentation by the cocultures.

  6. Study of Wastewaters Contaminated with Heavy Metals in Bioethanol Production

    NASA Astrophysics Data System (ADS)

    Bartošová, Alica; Blinová, Lenka

    2017-06-01

    Bioethanol as a substitute for traditional sources of energy, especially oil transport, is currently one of the most researched alternative motor fuels. Normally, bioethanol is produced from agricultural crops such as sugar cane or corn. However, this is counter-productive, because agriculture is primarily serving to ensure enough food for the people. It is therefore necessary to look for new production of appropriate non-food crops or find an added value to this process. Utilisation of contaminated water from metal industry could be one of them. Based on the hypothesis of reduction of some toxic metals with higher oxidation number is opening the possibility of using this wastewater in alcohol fermentation of any kind of biomass. In this study, hexavalent chromium Cr(VI) was used as a model contaminant in the process of aerobic fermentation of corn to bioethanol. To determine the reduction potential of glucose to Cr(VI), and to quantitatively determinate the glucose content after saccharification, UV/VIS spectrophotometry was used. As a method of qualitative determination of fermentation product, gas chromatography with mass detection was used. Infrared spectrometry was used for qualitative analyses of produced ethanol. Based on the established results shown in this paper, we can conclude that the presence of hexavalent chromium in the fermentation process does not have a significant negative impact, while offering the opportunity of using the industrial wastewaters for the production of bioethanol fuel.

  7. Autohydrolysis Pretreatment of Lignocellulosic Biomass for Bioethanol Production

    NASA Astrophysics Data System (ADS)

    Han, Qiang

    Autohydrolysis, a simple and environmental friendly process, has long been studied but often abandoned as a financially viable pretreatment for bioethanol production due to the low yields of fermentable sugars at economic enzyme dosages. The introduction of mechanical refining can generate substantial improvements for autohydrolysis process, making it an attractive pretreatment technology for bioethanol commercialization. In this study, several lignocellulosic biomass including wheat straw, switchgrass, corn stover, waste wheat straw have been subjected to autohydrolysis pretreatment followed by mechanical refining to evaluate the total sugar recovery at affordable enzyme dosages. Encouraging results have been found that using autohydrolysis plus refining strategy, the total sugar recovery of most feedstock can be as high as 76% at 4 FPU/g enzymes dosages. The mechanical refining contributed to the improvement of enzymatic sugar yield by as much as 30%. Three non-woody biomass (sugarcane bagasse, wheat straw, and switchgrass) and three woody biomass (maple, sweet gum, and nitens) have been subjected to autohydrolysis pretreatment to acquire a fundamental understanding of biomass characteristics that affect the autohydrolysis and the following enzymatic hydrolysis. It is of interest to note that the nonwoody biomass went through substantial delignification during autohydrolysis compared to woody biomass due to a significant amount of p-coumaric acid and ferulic acid. It has been found that hardwood which has a higher S/V ratio in the lignin structure tends to have a higher total sugar recovery from autohydrolysis pretreatment. The economics of bioethanol production from autohydrolysis of different feedstocks have been investigated. Regardless of different feedstocks, in the conventional design, producing bioethanol and co-producing steam and power, the minimum ethanol revenues (MER) required to generate a 12% internal rate of return (IRR) are high enough to

  8. Recent Advances on Bioethanol Dehydration using Zeolite Membrane

    NASA Astrophysics Data System (ADS)

    Makertihartha, I. G. B. N.; Dharmawijaya, P. T.; Wenten, I. G.

    2017-07-01

    Renewable energy has gained increasing attention throughout the world. Bioethanol has the potential to replace existing fossil fuel usage without much modification in existing facilities. Bioethanol which generally produced from fermentation route produces low ethanol concentration. However, fuel grade ethanol requires low water content to avoid engine stall. Dehydration process has been increasingly important in fuel grade ethanol production. Among all dehydration processes, pervaporation is considered as the most promising technology. Zeolite possesses high potential in pervaporation of bioethanol into fuel grade ethanol. Zeolite membrane can either remove organic (ethanol) from aqueous mixture or water from the mixture, depending on the framework used. Hydrophilic zeolite membrane, e.g. LTA, can easily remove water from the mixture leaving high ethanol concentration. On the other hand, hydrophobic zeolite membrane, e.g. silicate-1, can remove ethanol from aqueous solution. This review presents the concept of bioethanol dehydration using zeolite membrane. Special attention is given to the performance of selected pathway related to framework selection.

  9. Experimental investigation of bioethanol liquid phase dehydration using natural clinoptilolite

    PubMed Central

    Karimi, Samira; Ghobadian, Barat; Omidkhah, Mohammad-Reza; Towfighi, Jafar; Tavakkoli Yaraki, Mohammad

    2016-01-01

    An experimental study of bioethanol adsorption on natural Iranian clinoptilolite was carried out. Dynamic breakthrough curves were used to investigate the best adsorption conditions in bioethanol liquid phase. A laboratory setup was designed and fabricated for this purpose. In order to find the best operating conditions, the effect of liquid pressure, temperature and flow rate on breakthrough curves and consequently, maximum ethanol uptake by adsorbent were studied. The effects of different variables on final bioethanol concentration were investigated using Response Surface Methodology (RSM). The results showed that by working at optimum condition, feed with 96% (v/v) initial ethanol concentration could be purified up to 99.9% (v/v). In addition, the process was modeled using Box–Behnken model and optimum operational conditions to reach 99.9% for final ethanol concentration were found equal to 10.7 °C, 4.9 bar and 8 mL/min for liquid temperature, pressure and flow rate, respectively. Therefore, the selected natural Iranian clinoptilolite was found to be a promising adsorbent material for bioethanol dehydration process. PMID:27222748

  10. Experimental investigation of bioethanol liquid phase dehydration using natural clinoptilolite.

    PubMed

    Karimi, Samira; Ghobadian, Barat; Omidkhah, Mohammad-Reza; Towfighi, Jafar; Tavakkoli Yaraki, Mohammad

    2016-05-01

    An experimental study of bioethanol adsorption on natural Iranian clinoptilolite was carried out. Dynamic breakthrough curves were used to investigate the best adsorption conditions in bioethanol liquid phase. A laboratory setup was designed and fabricated for this purpose. In order to find the best operating conditions, the effect of liquid pressure, temperature and flow rate on breakthrough curves and consequently, maximum ethanol uptake by adsorbent were studied. The effects of different variables on final bioethanol concentration were investigated using Response Surface Methodology (RSM). The results showed that by working at optimum condition, feed with 96% (v/v) initial ethanol concentration could be purified up to 99.9% (v/v). In addition, the process was modeled using Box-Behnken model and optimum operational conditions to reach 99.9% for final ethanol concentration were found equal to 10.7 °C, 4.9 bar and 8 mL/min for liquid temperature, pressure and flow rate, respectively. Therefore, the selected natural Iranian clinoptilolite was found to be a promising adsorbent material for bioethanol dehydration process.

  11. Looking beyond Saccharomyces: the potential of non-conventional yeast species for desirable traits in bioethanol fermentation.

    PubMed

    Radecka, Dorota; Mukherjee, Vaskar; Mateo, Raquel Quintilla; Stojiljkovic, Marija; Foulquié-Moreno, María R; Thevelein, Johan M

    2015-09-01

    Saccharomyces cerevisiae has been used for millennia in the production of food and beverages and is by far the most studied yeast species. Currently, it is also the most used microorganism in the production of first-generation bioethanol from sugar or starch crops. Second-generation bioethanol, on the other hand, is produced from lignocellulosic feedstocks that are pretreated and hydrolyzed to obtain monomeric sugars, mainly D-glucose, D-xylose and L-arabinose. Recently, S. cerevisiae recombinant strains capable of fermenting pentose sugars have been generated. However, the pretreatment of the biomass results in hydrolysates with high osmolarity and high concentrations of inhibitors. These compounds negatively influence the fermentation process. Therefore, robust strains with high stress tolerance are required. Up to now, more than 2000 yeast species have been described and some of these could provide a solution to these limitations because of their high tolerance to the most predominant stress conditions present in a second-generation bioethanol reactor. In this review, we will summarize what is known about the non-conventional yeast species showing unusual tolerance to these stresses, namely Zygosaccharomyces rouxii (osmotolerance), Kluyveromyces marxianus and Ogataea (Hansenula) polymorpha (thermotolerance), Dekkera bruxellensis (ethanol tolerance), Pichia kudriavzevii (furan derivatives tolerance) and Z. bailii (acetic acid tolerance).

  12. Thermodynamic evaluation of hydrogen production via bioethanol steam reforming

    NASA Astrophysics Data System (ADS)

    Tasnadi-Asztalos, Zsolt; Cormos, Ana-Maria; Imre-Lucaci, Árpád; Cormos, Cǎlin C.

    2013-11-01

    In this article, a thermodynamic analysis for bioethanol steam reforming for hydrogen production is presented. Bioethanol is a newly proposed renewable energy carrier mainly produced from biomass fermentation. Reforming of bioethanol provides a promising method for hydrogen production from renewable resources. Steam reforming of ethanol (SRE) takes place under the action of a metal catalyst capable of breaking C-C bonds into smaller molecules. A large domain for the water/bioethanol molar ratio as well as the temperature and average pressure has been used in the present work. The interval of investigated temperature was 100-800°C, the pressure was in the range of 1-10 bar and the molar ratio was between 3-25. The variations of gaseous species concentration e.g. H2, CO, CO2, CH4 were analyzed. The concentrations of the main products (H2 and CO) at lower temperature are smaller than the ones at higher temperature due to by-products formation (methane, carbon dioxide, acetylene etc.). The concentration of H2 obtained in the process using high molar ratio (>20) is higher than the one at small molar ratio (near stoichiometric). When the pressure is increased the hydrogen concentration decreases. The results were compared with literature data for validation purposes.

  13. Thermodynamic evaluation of hydrogen production via bioethanol steam reforming

    SciTech Connect

    Tasnadi-Asztalos, Zsolt; Cormos, Ana-Maria; Imre-Lucaci, Árpád; Cormos, Călin C.

    2013-11-13

    In this article, a thermodynamic analysis for bioethanol steam reforming for hydrogen production is presented. Bioethanol is a newly proposed renewable energy carrier mainly produced from biomass fermentation. Reforming of bioethanol provides a promising method for hydrogen production from renewable resources. Steam reforming of ethanol (SRE) takes place under the action of a metal catalyst capable of breaking C-C bonds into smaller molecules. A large domain for the water/bioethanol molar ratio as well as the temperature and average pressure has been used in the present work. The interval of investigated temperature was 100-800°C, the pressure was in the range of 1-10 bar and the molar ratio was between 3-25. The variations of gaseous species concentration e.g. H{sub 2}, CO, CO{sub 2}, CH{sub 4} were analyzed. The concentrations of the main products (H{sub 2} and CO) at lower temperature are smaller than the ones at higher temperature due to by-products formation (methane, carbon dioxide, acetylene etc.). The concentration of H2 obtained in the process using high molar ratio (>20) is higher than the one at small molar ratio (near stoichiometric). When the pressure is increased the hydrogen concentration decreases. The results were compared with literature data for validation purposes.

  14. Ultrasound-assisted bioethanol production from waste newspaper.

    PubMed

    Subhedar, Preeti B; Gogate, Parag R

    2015-11-01

    The present work deals with intensification of bioethanol production from waste newspaper using Saccharomyces cerevisiae using ultrasonic irradiations. The effect of different process parameters such as application of ultrasonic irradiation at different growth phases, irradiation time, ultrasonic power and duty cycle on the bioethanol production has been investigated. The favorable conditions for the maximum yield were established as application of ultrasonic irradiation (duration of 10 min) to fermentation broth at 12 h of growth phase with 25 kHz frequency, 160 W power and 20% duty cycle. The bioethanol productivity was increased by 1.8 times from 7.8 to 14.1 g/L compared with the non-sonicated control fermentation. Decrease in glucose concentration from 0.63% to 0.2% w/v in ultrasound-assisted fermentation confirmed the improved substrate uptake of the microbial cell due to the application of ultrasound. ESEM analysis also confirmed the changes in the cell morphology leading to improved cell permeability. Results were fitted to an unstructured kinetic model comprising of the kinetic and physiological parameters. Overall, the work has demonstrated an intensified approach for the bioethanol production based on the use of ultrasound. Copyright © 2015 Elsevier B.V. All rights reserved.

  15. A Life Cycle Assessment (LCA) comparison of three management options for waste papers: bioethanol production, recycling and incineration with energy recovery.

    PubMed

    Wang, Lei; Templer, Richard; Murphy, Richard J

    2012-09-01

    This study uses Life Cycle Assessment (LCA) to assess the environmental profiles and greenhouse gas (GHG) emissions for bioethanol production from waste papers and to compare them with the alternative waste management options of recycling or incineration with energy recovery. Bioethanol production scenarios both with and without pre-treatments were conducted. It was found that an oxidative lime pre-treatment reduced GHG emissions and overall environmental burdens for a newspaper-to-bioethanol process whereas a dilute acid pre-treatment raised GHG emissions and overall environmental impacts for an office paper-to-bioethanol process. In the comparison of bioethanol production systems with alternative management of waste papers by different technologies, it was found that the environmental profiles of each system vary significantly and this variation affects the outcomes of the specific comparisons made. Overall, a number of configurations of bioethanol production from waste papers offer environmentally favourable or neutral profiles when compared with recycling or incineration.

  16. The water footprint of sweeteners and bio-ethanol.

    PubMed

    Gerbens-Leenes, Winnie; Hoekstra, Arjen Y

    2012-04-01

    An increasing demand for food together with a growing demand for energy crops result in an increasing demand for and competition over water. Sugar cane, sugar beet and maize are not only essential food crops, but also important feedstock for bio-ethanol. Crop growth requires water, a scarce resource. This study aims to assess the green, blue and grey water footprint (WF) of sweeteners and bio-ethanol from sugar cane, sugar beet and maize in the main producing countries. The WFs of sweeteners and bio-ethanol are mainly determined by the crop type that is used as a source and by agricultural practise and agro-climatic conditions; process water footprints are relatively small. The weighted global average WF of sugar cane is 209 m(3)/tonne; for sugar beet this is 133 m(3)/tonne and for maize 1222 m(3)/tonne. Large regional differences in WFs indicate that WFs of crops for sweeteners and bio-ethanol can be improved. It is more favourable to use maize as a feedstock for sweeteners or bio-ethanol than sugar beet or sugar cane. The WF of sugar cane contributes to water stress in the Indus and Ganges basins. In the Ukraine, the large grey WF of sugar beet contributes to water pollution. In some western European countries, blue WFs of sugar beet and maize need a large amount of available blue water for agriculture. The allocation of the limited global water resources to bio-energy on a large scale will be at the cost of water allocation to food and nature. Copyright © 2011 Elsevier Ltd. All rights reserved.

  17. Fueling industrial biotechnology growth with bioethanol.

    PubMed

    Otero, José Manuel; Panagiotou, Gianni; Olsson, Lisbeth

    2007-01-01

    Industrial biotechnology is the conversion of biomass via biocatalysis, microbial fermentation, or cell culture to produce chemicals, materials, and/or energy. Industrial biotechnology processes aim to be cost-competitive, environmentally favorable, and self-sustaining compared to their petrochemical equivalents. Common to all processes for the production of energy, commodity, added value, or fine chemicals is that raw materials comprise the most significant cost fraction, particularly as operating efficiencies increase through practice and improving technologies. Today, crude petroleum represents the dominant raw material for the energy and chemical sectors worldwide. Within the last 5 years petroleum prices, stability, and supply have increased, decreased, and been threatened, respectively, driving a renewed interest across academic, government, and corporate centers to utilize biomass as an alternative raw material. Specifically, bio-based ethanol as an alternative biofuel has emerged as the single largest biotechnology commodity, with close to 46 billion L produced worldwide in 2005. Bioethanol is a leading example of how systems biology tools have significantly enhanced metabolic engineering, inverse metabolic engineering, and protein and enzyme engineering strategies. This enhancement stems from method development for measurement, analysis, and data integration of functional genomics, including the transcriptome, proteome, metabolome, and fluxome. This review will show that future industrial biotechnology process development will benefit tremendously from the precedent set by bioethanol - that enabling technologies (e.g., systems biology tools) coupled with favorable economic and socio-political driving forces do yield profitable, sustainable, and environmentally responsible processes. Biofuel will continue to be the keystone of any industrial biotechnology-based economy whereby biorefineries leverage common raw materials and unit operations to integrate

  18. Use of different extracts of coffee pulp for the production of bioethanol.

    PubMed

    Menezes, Evandro Galvão Tavares; do Carmo, Juliana Ribeiro; Menezes, Aline Galvão Tavares; Alves, José Guilherme Lembi Ferreira; Pimenta, Carlos José; Queiroz, Fabiana

    2013-01-01

    Coffee is one of the most important agricultural products in Brazil. More than 50 % of the coffee fruit is not used for the production of commercial green coffee and is therefore discarded, usually ending up in the environment. The goal of this work was to select an efficient process for obtaining coffee pulp extract and to evaluate the use of this extract in bioethanol production. The effects of heat treatment and trituration on the yield and composition of the extract were investigated by measuring the amounts of reducing sugars, starch, pectin, and phenolic compounds. The extraction process was most efficient at room temperature using grinding followed by pressing. Five different fermentation media were tested: sugarcane juice or molasses diluted with water or with coffee pulp extract and a medium with only coffee pulp extract. Batch fermentations were carried out at 30 °C for 24 h, and samples were taken to obtain measurements of the total reducing sugars, cell count, and ethanol concentration. The addition of coffee pulp extract did not influence the fermentation or yeast viability, and it can thus be mixed with sugarcane juice or molasses for the production of bioethanol, with a yield of approximately 70 g/L.

  19. Energy consumption evaluation of fuel bioethanol production from sweet potato.

    PubMed

    Ferrari, Mario Daniel; Guigou, Mairan; Lareo, Claudia

    2013-05-01

    The energy consumption for different operative conditions and configurations of the bioethanol production industrial process from an experimental variety of sweet potato (Ipomea batatas) K 9807.1 was evaluated. A process simulation model was developed using SuperPro Designer® software. The model was based on experimental data gathered from our laboratory experiments and technology and equipment suppliers. The effects of the dry matter ratio of sweet potato to water, the fermentation efficiency, and sweet potato sugar content, on the energy consumption (steam and electricity) were respectively evaluated. All factors were significant. The best ratio of dry matter to total water to work with fresh sweet potato was 0.2 kg dry sweet potato/kg water, as for greater ratios was not found a significant reduction in energy consumption. Also, the drying of the sweet potato previous its processing was studied. It presented an energy consumption greater than the energetic content of the bioethanol produced.

  20. Feasibility and energetic evaluation of air stripping for bioethanol production.

    PubMed

    Schläfle, Sandra; Senn, Thomas; Gschwind, Peter; Kohlus, Reinhard

    2017-05-01

    Stripping of mashes with air as stripping gas and low ethanol contents between 3 and 5wt% was investigated in terms of its suitability for continuous bioethanol production. Experiments in a Blenke cascade system were carried out and the results were compared with values obtained from theoretical vapour-liquid-equilibrium calculations. The whole stripping process was energetically evaluated by a simulation in ChemCAD and compared to conventional distillation. Therefore several parameters such as temperature, air volume flow and initial ethanol load of the mash were varied. Air stripping was found to be a suitable separation method for bioethanol from mashes with low concentrations. However, energetic aspects have to be considered, when developing a new process. Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. Plant-based food and feed protein structure changes induced by gene-transformation, heating and bio-ethanol processing: a synchrotron-based molecular structure and nutrition research program.

    PubMed

    Yu, Peiqiang

    2010-11-01

    Unlike traditional "wet" analytical methods which during processing for analysis often result in destruction or alteration of the intrinsic protein structures, advanced synchrotron radiation-based Fourier transform infrared microspectroscopy has been developed as a rapid and nondestructive and bioanalytical technique. This cutting-edge synchrotron-based bioanalytical technology, taking advantages of synchrotron light brightness (million times brighter than sun), is capable of exploring the molecular chemistry or structure of a biological tissue without destruction inherent structures at ultra-spatial resolutions. In this article, a novel approach is introduced to show the potential of the advanced synchrotron-based analytical technology, which can be used to study plant-based food or feed protein molecular structure in relation to nutrient utilization and availability. Recent progress was reported on using synchrotron-based bioanalytical technique synchrotron radiation-based Fourier transform infrared microspectroscopy and diffused reflectance infrared Fourier transform spectroscopy to detect the effects of gene-transformation (Application 1), autoclaving (Application 2), and bio-ethanol processing (Application 3) on plant-based food and feed protein structure changes on a molecular basis. The synchrotron-based technology provides a new approach for plant-based protein structure research at ultra-spatial resolutions at cellular and molecular levels.

  2. Plant-based Food and Feed Protein Structure Changes Induced by Gene-transformation heating and bio-ethanol processing: A Synchrotron-based Molecular Structure and Nutrition Research Program

    SciTech Connect

    P Yu

    2011-12-31

    Unlike traditional 'wet' analytical methods which during processing for analysis often result in destruction or alteration of the intrinsic protein structures, advanced synchrotron radiation-based Fourier transform infrared microspectroscopy has been developed as a rapid and nondestructive and bioanalytical technique. This cutting-edge synchrotron-based bioanalytical technology, taking advantages of synchrotron light brightness (million times brighter than sun), is capable of exploring the molecular chemistry or structure of a biological tissue without destruction inherent structures at ultra-spatial resolutions. In this article, a novel approach is introduced to show the potential of the advanced synchrotron-based analytical technology, which can be used to study plant-based food or feed protein molecular structure in relation to nutrient utilization and availability. Recent progress was reported on using synchrotron-based bioanalytical technique synchrotron radiation-based Fourier transform infrared microspectroscopy and diffused reflectance infrared Fourier transform spectroscopy to detect the effects of gene-transformation (Application 1), autoclaving (Application 2), and bio-ethanol processing (Application 3) on plant-based food and feed protein structure changes on a molecular basis. The synchrotron-based technology provides a new approach for plant-based protein structure research at ultra-spatial resolutions at cellular and molecular levels.

  3. Techno-economic potential of bioethanol from bamboo in China

    PubMed Central

    2013-01-01

    Background Bamboo is potentially an interesting feedstock for advanced bioethanol production in China due to its natural abundance, rapid growth, perennial nature and low management requirements. Liquid hot water (LHW) pretreatment was selected as a promising technology to enhance sugar release from bamboo lignocellulose whilst keeping economic and environmental costs to a minimum. The present research was conducted to assess: 1) by how much LHW pretreatment can enhance sugar yields in bamboo, and 2) whether this process has the potential to be economically feasible for biofuel use at the commercial scale. Pretreatments were performed at temperatures of 170-190°C for 10–30 minutes, followed by enzymatic saccharification with a commercial enzyme cocktail at various loadings. These data were then used as inputs to a techno-economic model using AspenPlus™ to determine the production cost of bioethanol from bamboo in China. Results At the selected LHW pretreatment of 190°C for 10 minutes, 69% of the initial sugars were released under a standardised enzyme loading; this varied between 59-76% when 10–140 FPU/g glucan of commercial enzyme Cellic CTec2 was applied. Although the lowest enzyme loading yielded the least amount of bioethanol, the techno-economic evaluation revealed it to be the most economically viable scenario with a production cost of $0.484 per litre (with tax exemption and a $0.16/litre subsidy). The supply-chain analysis demonstrated that bioethanol could be economically competitive with petrol at the pump at enzyme loadings up to 60 FPU/g glucan. However, in a prospective scenario with reduced government support, this enzyme loading threshold would be reduced to 30 FPU/g glucan. Conclusions Bioethanol from bamboo is shown to be both technically and economically feasible, as well as competitive with petrol in China. Alternative approaches to reduce bioethanol production costs are still needed however, to ensure its competitiveness in a possible

  4. Dynamic global sensitivity analysis in bioreactor networks for bioethanol production.

    PubMed

    Ochoa, M P; Estrada, V; Di Maggio, J; Hoch, P M

    2016-01-01

    Dynamic global sensitivity analysis (GSA) was performed for three different dynamic bioreactor models of increasing complexity: a fermenter for bioethanol production, a bioreactors network, where two types of bioreactors were considered: aerobic for biomass production and anaerobic for bioethanol production and a co-fermenter bioreactor, to identify the parameters that most contribute to uncertainty in model outputs. Sobol's method was used to calculate time profiles for sensitivity indices. Numerical results have shown the time-variant influence of uncertain parameters on model variables. Most influential model parameters have been determined. For the model of the bioethanol fermenter, μmax (maximum growth rate) and Ks (half-saturation constant) are the parameters with largest contribution to model variables uncertainty; in the bioreactors network, the most influential parameter is μmax,1 (maximum growth rate in bioreactor 1); whereas λ (glucose-to-total sugars concentration ratio in the feed) is the most influential parameter over all model variables in the co-fermentation bioreactor.

  5. Microalgae for economic applications: advantages and perspectives for bioethanol.

    PubMed

    Simas-Rodrigues, Cíntia; Villela, Helena D M; Martins, Aline P; Marques, Luiza G; Colepicolo, Pio; Tonon, Angela P

    2015-07-01

    Renewable energy has attracted significant interest in recent years as a result of sustainability, environmental impact, and socio-economic considerations. Given existing technological knowledge and based on projections relating to biofuels derived from microalgae, microalgal feedstock is considered to be one of the most important renewable energy sources potentially available for industrial production. Therefore, this review examines microalgal bioethanol technology, which converts biomass from microalgae to fuel, the chemical processes involved, and possible ways of increasing the bioethanol yield, such as abiotic factors and genetic manipulation of fermenting organisms. © The Author 2015. Published by Oxford University Press on behalf of the Society for Experimental Biology. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  6. Algal biomass conversion to bioethanol - a step-by-step assessment.

    PubMed

    Harun, Razif; Yip, Jason W S; Thiruvenkadam, Selvakumar; Ghani, Wan A W A K; Cherrington, Tamara; Danquah, Michael K

    2014-01-01

    The continuous growth in global population and the ongoing development of countries such as China and India have contributed to a rapid increase in worldwide energy demand. Fossil fuels such as oil and gas are finite resources, and their current rate of consumption cannot be sustained. This, coupled with fossil fuels' role as pollutants and their contribution to global warming, has led to increased interest in alternative sources of energy production. Bioethanol, presently produced from energy crops, is one such promising alternative future energy source and much research is underway in optimizing its production. The economic and temporal constraints that crop feedstocks pose are the main downfalls in terms of the commercial viability of bioethanol production. As an alternative to crop feedstocks, significant research efforts have been put into utilizing algal biomass as a feedstock for bioethanol production. Whilst the overall process can vary, the conversion of biomass to bioethanol usually contains the following steps: (i) pretreatment of feedstock; (ii) hydrolysis; and (iii) fermentation of bioethanol. This paper reviews different technologies utilized in the pretreatment and fermentation steps, and critically assesses their applicability to bioethanol production from algal biomass. Two different established fermentation routes, single-stage fermentation and two-stage gasification/fermentation processes, are discussed. The viability of algal biomass as an alternative feedstock has been assessed adequately, and further research optimisation must be guided toward the development of cost-effective scalable methods to produce high bioethanol yield under optimum economy. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. Bioethanol fermentation as alternative valorization route of agricultural digestate according to a biorefinery approach.

    PubMed

    Sambusiti, C; Monlau, F; Barakat, A

    2016-07-01

    This study investigates the feasibility of producing bioethanol from solid digestate after a mechanical fractionation (i.e. centrifugal milling), in order to improve the energy recovery from agricultural wastes and the sustainability of anaerobic digestion plants. A bioethanol yield of 37gkg(-1)TS was evaluated for the solid digestate fraction. Mass and energetic balances were performed and compared between two scenarios: (A) one-stage bioethanol fermentation and (B) two-stage anaerobic digestion-bioethanol fermentation, in order to evaluate the feasibility and the advantages of the two-stage process. Results revealed that, compared to the one-stage process, the dual anaerobic digestion-bioethanol process permitted: (i) to diversify biofuels production; (ii) to provide the thermal energy sufficient for drying digestate (13,351kWhthday(-1)), for the subsequent milling step; (iii) to reduce the electric energy requirement for the milling step (from 23,880 to 3580kWhelday(-1)); (iv) to produce extra electrical energy of 8483kWhelday(-1); (v) to improve the reduction of waste streams generated (from 13% to 54% of organic matter removal).

  8. Scale-up and kinetic modeling for bioethanol production.

    PubMed

    Imamoglu, Esra; Sukan, Fazilet Vardar

    2013-09-01

    Bioethanol was produced from acidic hydrolysate of rice hulls using recombinant Escherichia coli KO11. Two different issues (scale-up and kinetic modeling) were evaluated simultaneously and concomitantly for bioethanol production. During the step-wise scale-up process from 100 mL shaken flask to 10 L stirred-tank bioreactor, the constant Reynolds number and the constant impeller tip speed were evaluated as scale-up methodologies under laboratory conditions. It was determined that the volumetric bioethanol productivity was 88% higher in 10 L bioreactor in comparison to the value of 0.21 g L(-1) h(-1) in shaken flask. The modified Monod and Luedeking-Piret models provided an accurate approach for the modeling of the experimental data. Ethanol concentration reached the maximum level of 29.03 g/L, which was 5% higher than the value of model prediction in 10 L bioreactor. The findings of this research could contribute to the industrial scale productions especially from lignocellulosic raw materials.

  9. Hybrid optical fiber sensor and artificial neural network system for bioethanol quality control and productivity enhancement

    NASA Astrophysics Data System (ADS)

    Gusken, Edmilton; Salgado, Ricardo M.; Rossell, Carlos E. V.; Ohishi, Takaaki; Suzuki, Carlos K.

    2008-04-01

    Bioethanol is produced by bio-chemical process that converts sugar or biomass feedstock into ethanol. After bio-chemical process, the solution is distilled under controlled conditions of pressure and temperature, in order to obtain an ethanol-water solution. However, the ethanol concentration analysis is generally performed off-line and, sometimes, a re-distillation process becomes necessary. In this research, an optical apparatus based on Fresnel reflection has been used in combination with artificial neural networks for determination of bioethanol concentration in hydro-alcoholic solution at any temperature. The volumetric concentration and temperature effect was investigated. This intelligent system can effectively detect and update in real-time the correction of distillation parameters to reduce losses of bioethanol and also to improve the quality in a production plant.

  10. Particulate size of microalgal biomass affects hydrolysate properties and bioethanol concentration.

    PubMed

    Harun, Razif; Danquah, Michael K; Thiruvenkadam, Selvakumar

    2014-01-01

    Effective optimization of microalgae-to-bioethanol process systems hinges on an in-depth characterization of key process parameters relevant to the overall bioprocess engineering. One of the such important variables is the biomass particle size distribution and the effects on saccharification levels and bioethanol titres. This study examined the effects of three different microalgal biomass particle size ranges, 35 μm ≤ x ≤ 90 μm, 125 μm ≤ x ≤ 180 μm, and 295 μm ≤ x ≤ 425 μm, on the degree of enzymatic hydrolysis and bioethanol production. Two scenarios were investigated: single enzyme hydrolysis (cellulase) and double enzyme hydrolysis (cellulase and cellobiase). The glucose yield from biomass in the smallest particle size range (35 μm ≤ x ≤ 90 μm) was the highest, 134.73 mg glucose/g algae, while the yield from biomass in the larger particle size range (295 μm ≤ x ≤ 425 μm) was 75.45 mg glucose/g algae. A similar trend was observed for bioethanol yield, with the highest yield of 0.47 g EtOH/g glucose obtained from biomass in the smallest particle size range. The results have shown that the microalgal biomass particle size has a significant effect on enzymatic hydrolysis and bioethanol yield.

  11. Improved Bioethanol Production Using Activated Carbon-treated Acid Hydrolysate from Corn Hull in Pachysolen tannophilus

    PubMed Central

    Seo, Hyeon-Beom; Kim, Seungseop; Lee, Hyeon-Yong

    2009-01-01

    To optimally convert corn hull, a byproduct from corn processing, into bioethanol using Pachysolen tannophlius, we investigated the optimal conditions for hydrolysis and removal of toxic substances in the hydrolysate via activated carbon treatment as well as the effects of this detoxification process on the kinetic parameters of bioethanol production. Maximum monosaccharide concentrations were obtained in hydrolysates in which 20 g of corn hull was hydrolyzed in 4% (v/v) H2SO4. Activated carbon treatment removed 92.3% of phenolic compounds from the hydrolysate. When untreated hydrolysate was used, the monosaccharides were not completely consumed, even at 480 h of culture. When activated carbon-treated hydrolysate was used, the monosaccharides were mostly consumed at 192 h of culture. In particular, when activated carbon-treated hydrolysate was used, bioethanol productivity (P) and specific bioethanol production rate (Qp) were 2.4 times and 3.4 times greater, respectively, compared to untreated hydrolysate. This was due to sustained bioethanol production during the period of xylose/arabinose utilization, which occurred only when activated carbon-treated hydrolysate was used. PMID:23983522

  12. Particulate Size of Microalgal Biomass Affects Hydrolysate Properties and Bioethanol Concentration

    PubMed Central

    Harun, Razif; Danquah, Michael K.; Thiruvenkadam, Selvakumar

    2014-01-01

    Effective optimization of microalgae-to-bioethanol process systems hinges on an in-depth characterization of key process parameters relevant to the overall bioprocess engineering. One of the such important variables is the biomass particle size distribution and the effects on saccharification levels and bioethanol titres. This study examined the effects of three different microalgal biomass particle size ranges, 35 μm ≤ x ≤ 90 μm, 125 μm ≤ x ≤ 180 μm, and 295 μm ≤ x ≤ 425 μm, on the degree of enzymatic hydrolysis and bioethanol production. Two scenarios were investigated: single enzyme hydrolysis (cellulase) and double enzyme hydrolysis (cellulase and cellobiase). The glucose yield from biomass in the smallest particle size range (35 μm ≤ x ≤ 90 μm) was the highest, 134.73 mg glucose/g algae, while the yield from biomass in the larger particle size range (295 μm ≤ x ≤ 425 μm) was 75.45 mg glucose/g algae. A similar trend was observed for bioethanol yield, with the highest yield of 0.47 g EtOH/g glucose obtained from biomass in the smallest particle size range. The results have shown that the microalgal biomass particle size has a significant effect on enzymatic hydrolysis and bioethanol yield. PMID:24971327

  13. Industrial processes influenced by gravity

    NASA Technical Reports Server (NTRS)

    Ostrach, Simon

    1988-01-01

    In considering new directions for low gravity research with particular regard to broadening the number and types of industrial involvements, it is noted that transport phenomena play a vital role in diverse processes in the chemical, pharmaceutical, food, and biotech industries. Relatively little attention has been given to the role of gravity in such processes. Accordingly, numerous industrial processes and phenomena are identified which involve gravity and/or surface tension forces. Phase separations and mixing are examples that will be significantly different in low gravity conditions. A basis is presented for expanding the scope of the low gravity research program and the potential benefits of such research is indicated.

  14. Environmental sustainability of bioethanol produced from sweet sorghum stem on saline-alkali land.

    PubMed

    Wang, Mingxin; Pan, Xinxing; Xia, Xunfeng; Xi, Beidou; Wang, Lijun

    2015-01-01

    Life cycle assessment was conducted to evaluate the energy efficiency and environmental impacts of a bioethanol production system that uses sweet sorghum stem on saline-alkali land as feedstock. The system comprises a plant cultivation unit, a feedstock transport unit, and a bioethanol conversion unit, with 1000L of bioethanol as a functional unit. The net energy ratio is 3.84, and the net energy gain is 17.21MJ/L. Agrochemical production consumes 76.58% of the life cycle fossil energy. The category with the most significant impact on the environment is eutrophication, followed by acidification, fresh water aquatic ecotoxicity, human toxicity, and global warming. Allocation method, waste recycling approach, and soil salinity significantly influence the results. Using vinasse to produce pellet fuel for steam generation significantly improves energy efficiency and decreases negative environmental impacts. Promoting reasonable management practices to alleviate saline stress and increasing agrochemical utilization efficiency can further improve environmental sustainability.

  15. Macroscopic modelling of bioethanol production from potato peel wastes in batch cultures supplemented with inorganic nitrogen.

    PubMed

    Richelle, A; Ben Tahar, I; Hassouna, M; Bogaerts, Ph

    2015-09-01

    Inorganic nitrogen supplementation is commonly used to boost fermentation metabolism in yeast cultures. However, an excessive addition can induce an opposite effect. Hence, it is important to ensure that the ammonia supplemented to the culture leads to an improvement of the ethanol production while avoiding undesirable inhibition effects. To this end, a macroscopic model describing the influence of ammonia addition on Saccharomyces cerevisiae metabolism during bioethanol production from potato peel wastes has been developed. The model parameters are obtained by a simplified identification methodology in five steps. It is validated with experimental data and successfully predicts the dynamics of growth, substrate consumption (ammonia and fermentable sugar sources) and bioethanol production, even in cross validation. The model is used to determine the optimal quantity of supplemented ammonia required for maximizing bioethanol production from potato peel wastes in batch cultures.

  16. Pretreatment efficiency and structural characterization of rice straw by an integrated process of dilute-acid and steam explosion for bioethanol production.

    PubMed

    Chen, Wen-Hua; Pen, Ben-Li; Yu, Ching-Tsung; Hwang, Wen-Song

    2011-02-01

    The combined pretreatment of rice straw using dilute-acid and steam explosion followed by enzymatic hydrolysis was investigated and compared with acid-catalyzed steam explosion pretreatment. In addition to measuring the chemical composition, including glucan, xylan and lignin content, changes in rice straw features after pretreatment were investigated in terms of the straw's physical properties. These properties included crystallinity, surface area, mean particle size and scanning electron microscopy imagery. The effect of acid concentration on the acid-catalyzed steam explosion was studied in a range between 1% and 15% acid at 180°C for 2 min. We also investigated the influence of the residence time of the steam explosion in the combined pretreatment and the optimum conditions for the dilute-acid hydrolysis step in order to develop an integrated process for the dilute-acid and steam explosion. The optimum operational conditions for the first dilute-acid hydrolysis step were determined to be 165°C for 2 min with 2% H(2)SO(4) and for the second steam explosion step was to be carried out at 180°C for 20 min; this gave the most favorable combination in terms of an integrated process. We found that rice straw pretreated by the dilute-acid/steam explosions had a higher xylose yield, a lower level of inhibitor in the hydrolysate and a greater degree of enzymatic hydrolysis; this resulted in a 1.5-fold increase in the overall sugar yield when compared to the acid-catalyzed steam explosion. Copyright © 2010 Elsevier Ltd. All rights reserved.

  17. Power, Influence Tactics, and Influence Processes in Virtual Teams

    ERIC Educational Resources Information Center

    Boughton, Marla

    2011-01-01

    Current studies of power, influence tactics, and influence processes in virtual teams assume that these constructs operate in a similar manner as they do in the face-to-face (FtF) environment. However, the virtual context differs from the FtF environment on a variety of dimensions, such as the availability of status cues. The differences between…

  18. Power, Influence Tactics, and Influence Processes in Virtual Teams

    ERIC Educational Resources Information Center

    Boughton, Marla

    2011-01-01

    Current studies of power, influence tactics, and influence processes in virtual teams assume that these constructs operate in a similar manner as they do in the face-to-face (FtF) environment. However, the virtual context differs from the FtF environment on a variety of dimensions, such as the availability of status cues. The differences between…

  19. Tannins Influence Soil Chemical Processes

    USDA-ARS?s Scientific Manuscript database

    Tannins, plant secondary compounds, can affect soil and water quality by interacting with inorganic and organic compounds. However, the fate of tannins and their effect on soil metal cycling dynamics and soil chemical processes is poorly understood. We examined the effects of commercial available ...

  20. Serpentinization processes: Influence of silica

    NASA Astrophysics Data System (ADS)

    Huang, R.; Sun, W.; Ding, X.; Song, M.; Zhan, W.

    2016-12-01

    Serpentinization systems are highly enriched in molecular hydrogen (H2) and hydrocarbons (e.g. methane, ethane and propane). The production of hydrocarbons results from reactions between H2 and oxidized carbon (carbon dioxide and carbon monoxide), which possibly contribute to climate changes during early history of the Earth. However, the influence of silica on the production of H2 and hydrocarbons was poorly constrained. We performed experiments at 311-500 °C and 3.0 kbar using mechanical mixtures of silica and olivine in ratios ranging from 0 to 40%. Molecular hydrogen (H2), methane, ethane and propane were formed, which were analyzed by gas chromatography. It was found that silica largely decreased H2 production. Without any silica, olivine serpentinization produced 94.5 mmol/kg H2 after 20 days of reaction time. By contrast, with the presence of 20% silica, H2 concentrations decreased largely, 8.5 mmol/kg. However, the influence of silica on the production of hydrocarbons is negligible. Moreover, with the addition of 20%-40% silica, the major hydrous minerals are talc, which was quantified according to an established standard curve calibrated by infrared spectroscopy analyses. It shows that silica greatly enhances olivine hydration, especially at 500 °C. Without any addition of silica, reaction extents were <5% at 17 days during olivine serpentinization at 500 °C and 3.0 kbar. By contrast, with the presence of 50% silica, olivine was completely transformed to talc within 9 days. This study indicates that silica impedes the oxidation of ferrous iron into ferric iron, and that rates of olivine hydration in natural geological settings are much faster with silica supply.

  1. Techno-economic analysis of bioethanol production from rice straw by liquid-state fermentation

    NASA Astrophysics Data System (ADS)

    Hidayata, M. H. M.; Salleh, S. F.; Riayatsyahb, T. M. I.; Aditiyac, H. B.; Mahliaa, T. M. I.; Shamsuddina, A. H.

    2016-03-01

    Renewable energy is the latest approach of the Malaysian government in an effort to find sustainable alternative energy sources and to fulfill the ever increasing energy demand. Being a country that thrives in the service and agricultural sector, bioethanol production from lignocellulosic biomass presents itself as a promising option. However, the lack of technical practicality and complexity in the operation system hinder it from being economically viable. Hence, this research acquired multiple case studies in order to provide an insight on the process involved and its implication on production as well as to obtain a cost analysis of bioethanol production. The energy input and cost of three main components of the bioethanol production which are the collection, logistics, and pretreatment of rice straw were evaluated extensively. The theoretical bioethanol yield and conversion efficiency obtained were 250 L/t and 60% respectively. The findings concluded that bioethanol production from rice straw is currently not economically feasible in Malaysia’s market due to lack of efficiency in the pretreatment phase and overbearing logistics and pretreatment costs. This work could serve as a reference to future studies of biofuel commercialization in Malaysia.

  2. Pretreatment optimization of the biomass of Microcystis aeruginosa for efficient bioethanol production.

    PubMed

    Khan, Muhammad Imran; Lee, Moon Geon; Shin, Jin Hyuk; Kim, Jong Deog

    2017-12-01

    Microalgae are considered to be the future promising sources of biofuels and bio products. The algal carbohydrates can be fermented to bioethanol after pretreatment process. Efficient pretreatment of the biomass is one of the major requirements for commercialization of the algal based biofuels. In present study the microalga, M. aeruginsa was used for pretreatment optimization and bioethanol production. Treatment of algal biomass with CaO before acid and/or enzymatic hydrolysis enhanced the degradation of algal cells. Monomeric sugars yield was increased more than twice when biomass was pretreated with CaO. Similarly, an increase was noted in the amount of fermentable sugars when biomass was subjected to invertase saccharification after acid or lysozyme pretreatment. Highest yield of fermentable sugars (16 mM/ml) in the centrifuged algal juice was obtained. 4 Different microorganisms' species were used individually and in combination for converting centrifuged algal juice to bioethanol. Comparatively higher yield of bioethanol (60 mM/ml) was obtained when the fermenter microorganisms were used in combination. The results demonstrated that M. arginase biomass can be efficiently pretreated to get higher yield of fermentable sugars for enhanced yield of bioethanol production.

  3. Pretreatment solution recycling and high-concentration output for economical production of bioethanol.

    PubMed

    Han, Minhee; Moon, Se-Kwon; Choi, Gi-Wook

    2014-11-01

    The purpose of this study was to enhance the economic efficiency of producing bioethanol. Pretreatment solution recycling is expected to increase economic efficiency by reducing the cost of pretreatment and the amount of wastewater. In addition, the production of high-concentration bioethanol could increase economic efficiency by reducing the energy cost of distillation. The pretreatment conditions were 95 °C, 0.72 M NaOH, 80 rpm twin-screw speed, and flow rate of 90 mL/min at 18 g/min of raw biomass feeding for pretreatment solution recycling. The pretreatment with NaOH solution recycling was conducted five times. All of the components and the pretreatment efficiency were similar, despite reuse. In addition, we developed a continuous biomass feeding system for production of high-concentration bioethanol. Using this reactor, the bioethanol productivity was investigated using various pretreated biomass feeding rates in a simultaneous saccharification and fermentation (SSF) process. The maximum ethanol concentration, yield, and productivity were 74.5 g/L, 89.5%, and 1.4 g/L h, respectively, at a pretreated biomass loading of approximately 25% (w/v) with an enzyme dosage of 30 FPU g/cellulose. The results presented here constitute an important contribution toward the production of bioethanol from Miscanthus.

  4. Hydrologic processes influencing meadow ecosystems [chapter 4

    Treesearch

    Mark L. Lord; David G. Jewett; Jerry R. Miller; Dru Germanoski; Jeanne C. Chambers

    2011-01-01

    The hydrologic regime exerts primary control on riparian meadow complexes and is strongly influenced by past and present geomorphic processes; biotic processes; and, in some cases, anthropogenic activities. Thus, it is essential to understand not only the hydrologic processes that operate within meadow complexes but also the interactions of meadow hydrology with other...

  5. Challenges for the production of bioethanol from biomass using recombinant yeasts.

    PubMed

    Kricka, William; Fitzpatrick, James; Bond, Ursula

    2015-01-01

    Lignocellulose biomass, one of the most abundant renewable resources on the planet, is an alternative sustainable energy source for the production of second-generation biofuels. Energy in the form of simple or complex carbohydrates can be extracted from lignocellulose biomass and fermented by microorganisms to produce bioethanol. Despite 40 years of active and cutting-edge research invested into the development of technologies to produce bioethanol from lignocellulosic biomass, the process remains commercially unviable. This review describes the achievements that have been made in generating microorganisms capable of utilizing both simple and complex sugars from lignocellulose biomass and the fermentation of these sugars into ethanol. We also provide a discussion on the current "roadblocks" standing in the way of making second-generation bioethanol a commercially viable alternative to fossil fuels. Copyright © 2015 Elsevier Inc. All rights reserved.

  6. The Influence of Different Strategies for the Saccharification of the Banana Plant Pseudostem and the Detoxification of Concentrated Broth on Bioethanol Production.

    PubMed

    de Souza, Elias Luiz; Sellin, Noeli; Marangoni, Cintia; Souza, Ozair

    2017-04-28

    Pseudostem of the Musa cavendishii banana plant was submitted to chemical pretreatments with acid (H2SO4 2%, 120 °C, 15 min) and with alkali (NaOH 3%, 120 °C, 15 min), saccharified by commercial enzymes Novozymes® (Cellic CTec2 and HTec2). The influences of the pretreatments on the degradation of the lignin, cellulose and hemicellulose, porosity of the surface, particle crystallinity, and yield in reducing sugars after saccharification (Y RS), were established. Different concentrations of biomass (70 and 100 g/L in dry matter (dm)), with different physical differences (dry granulated, crushed wet bagasse, and whole pseudostem), were used. The broth with the highest Y RS among the different strategies tested was evaporated until the concentration of reducing sugars (RS) was to the order of 100 g/L and fermented, with and without prior detoxification with active carbon. Fermentation was carried out in Erlenmeyer flasks, at 30 °C, initial pH 5.0, and 120 rpm. In comparison to the biomass without chemical pretreatment and to the biomass pretreated with NaOH, the acid pretreatment of 70 g/L of dry granulated biomass enabled greater digestion of hemicellulose, lower index of cellulose crystallinity, and higher Y RS (45.8 ± 0.7%). The RS increase in fermentation broth to 100 g/L, with posterior detoxification, presented higher productivity ethanol (Q P = 1.44 ± 0.02 g/L/h) with ethanol yield (Y P/RS) of 0.41 ± 0.02 g/g. The value of Q P was to the order of 75% higher than Q P obtained with the same broth without prior detoxification.

  7. Evaluation on Microalgae Biomass for Bioethanol Production

    NASA Astrophysics Data System (ADS)

    Chng, L. M.; Lee, K. T.; Chan, D. C. J.

    2017-06-01

    The depletion of energy resources has triggered worldwide concern for alternative sources, especially renewable energy. Microalgae biomass offers the most promising feedstock for renewable energy because of their impressive efficient growing characteristics and valuable composition. Simple cell structure of the microalgae would simplify the pretreatment technology thus increase the cost-effectiveness of biofuel production. Scenedesmus dimorphus is a carbohydrate-rich microalgae that has potential as biomass for bioethanol. The cultivation of Scenedesmus dimorphus under aeration of carbon dioxide enriched air resulted 1.47 g/L of dry biomass with composition of 12 w/w total lipid, 53.7 w/w carbohydrate and 17.4 protein. Prior to ethanolic fermentation with Saccharomyces cerevisiae, various pre-treatment methods were investigated to release and degrade the complex carbohydrate in cell biomass thus obtaining the maximal amount of digestible sugar for ethanolic yeast. In this study, sulfuric acid was used as hydrolysis agent while amyloglucosidase as enzymatic agent. Dried biomass via hydrothermal acidic hydrolysis yielded sugar which is about 89 of total carbohydrate at reaction temperature of 125 °C and acid concentration of 4 v/v. While combination of organosolv treatment (mixture of methanol and chloroform) with enzymatic hydrolysis yielded comparable amount of sugar with 0.568 g glucose/g treated-biomass. In this study, the significant information in pre-treatment process ensures the sustainability of the biofuel produced.

  8. Miscanthus as cellulosic biomass for bioethanol production.

    PubMed

    Lee, Wen-Chien; Kuan, Wei-Chih

    2015-06-01

    The members of the genus Miscanthus are potential feedstocks for biofuels because of the promising high yields of biomass per unit of planted area. This review addresses species, cultivation, and lignocellulose composition of Miscanthus, as well as pretreatment and enzyme saccharification of Miscanthus biomass for ethanol fermentation. The average cellulose contents in dried biomass of Miscanthus floridulus, Miscanthus sinensis, Miscanthus sacchariflorus, and Miscanthus × giganteus (M × G) are 37.2, 37.6, 38.9, and 41.1% wt/wt, respectively. A number of pretreatment methods have been applied in order to enhance digestibility of Miscanthus biomass for enzymatic saccharification. Pretreatment of Miscanthus using liquid hot water or alkaline results in a significant release of glucose; while glucose yields can be 90% or higher if a pretreatment like AFEX that combines both chemical and physical processes is used. As ethanol is produced by yeast fermentation of the hydrolysate from enzymatic hydrolysis of residual solids (pulp) after pretreatment, theoretical ethanol yields are 0.211-0.233 g/g-raw biomass if only cellulose is taken into account. Simultaneous saccharification and fermentation of pretreated M × G and M. lutarioriparius results in experimental ethanol yields of 0.13 and 0.15 g/g-raw biomass, respectively. Co-production of value-added products can reduce the overall production cost of bioethanol. Copyright © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. Genome Sequence of Pichia kudriavzevii M12, a Potential Producer of Bioethanol and Phytase

    PubMed Central

    Gan, Han Ming; Ling, How Lie; Rashid, Noor Aini Abdul

    2012-01-01

    A draft genome sequence of Pichia kudriavzevii M12 is presented here. The genome reveals the presence of genes encoding enzymes involved in xylose utilization and the pentose phosphate pathway for bioethanol production. Strain M12 is also a potential producer of phytases, enzymes useful in food processing and agriculture. PMID:23027839

  10. Cell-wall structural changes in wheat straw pretreated for bioethanol production

    Treesearch

    Jan B. Kristensen; G. Thygesen Lisbeth; Claus Felby; Henning Jorgensen; Thomas Elder

    2008-01-01

    Pretreatment is an essential step in the enzymatic hydrolysis of biomass and subsequent production of bioethanol. Recent results indicate that only a mild pretreatment is necessary in an industrial, economically feasible system. The Integrated Biomass Utilisation System hydrothermal pretreatment process has previously been shown to be effective in preparing wheat straw...

  11. Simulation of integrated first and second generation bioethanol production from sugarcane: comparison between different biomass pretreatment methods.

    PubMed

    Dias, Marina O S; da Cunha, Marcelo Pereira; Maciel Filho, Rubens; Bonomi, Antonio; Jesus, Charles D F; Rossell, Carlos E V

    2011-08-01

    Sugarcane bagasse is used as a fuel in conventional bioethanol production, providing heat and power for the plant; therefore, the amount of surplus bagasse available for use as raw material for second generation bioethanol production is related to the energy consumption of the bioethanol production process. Pentoses and lignin, byproducts of the second generation bioethanol production process, may be used as fuels, increasing the amount of surplus bagasse. In this work, simulations of the integrated bioethanol production process from sugarcane, surplus bagasse and trash were carried out. Selected pre-treatment methods followed, or not, by a delignification step were evaluated. The amount of lignocellulosic materials available for hydrolysis in each configuration was calculated assuming that 50% of sugarcane trash is recovered from the field. An economic risk analysis was carried out; the best results for the integrated first and second generation ethanol production process were obtained for steam explosion pretreatment, high solids loading for hydrolysis and 24-48 h hydrolysis. The second generation ethanol production process must be improved (e.g., decreasing required investment, improving yields and developing pentose fermentation to ethanol) in order for the integrated process to be more economically competitive.

  12. Integrated distillation-membrane process for bio-ethanol and bio-butanol recovery from actual fermentation broths: Separation energy efficiency and fate of secondary fermentation products

    EPA Science Inventory

    A hybrid process integrating vapor stripping with vapor compression and vapor permeation membrane separation, termed Membrane Assisted Vapor Stripping (MAVS), was evaluated for recovery and dehydration of ethanol and/or 1-butanol from aqueous solution as an alternative to convent...

  13. Integrated distillation-membrane process for bio-ethanol and bio-butanol recovery from actual fermentation broths: Separation energy efficiency and fate of secondary fermentation products

    EPA Science Inventory

    A hybrid process integrating vapor stripping with vapor compression and vapor permeation membrane separation, termed Membrane Assisted Vapor Stripping (MAVS), was evaluated for recovery and dehydration of ethanol and/or 1-butanol from aqueous solution as an alternative to convent...

  14. Bioethanol production: an integrated process of low substrate loading hydrolysis-high sugars liquid fermentation and solid state fermentation of enzymatic hydrolysis residue.

    PubMed

    Chu, Qiulu; Li, Xin; Ma, Bin; Xu, Yong; Ouyang, Jia; Zhu, Junjun; Yu, Shiyuan; Yong, Qiang

    2012-11-01

    An integrated process of enzymatic hydrolysis and fermentation was investigated for high ethanol production. The combination of enzymatic hydrolysis at low substrate loading, liquid fermentation of high sugars concentration and solid state fermentation of enzymatic hydrolysis residue was beneficial for conversion of steam explosion pretreated corn stover to ethanol. The results suggested that low substrate loading hydrolysis caused a high enzymatic hydrolysis yield; the liquid fermentation of about 200g/L glucose by Saccharomyces cerevisiae provided a high ethanol concentration which could significantly decrease cost of the subsequent ethanol distillation. A solid state fermentation of enzymatic hydrolysis residue was combined, which was available to enhance ethanol production and cellulose-to-ethanol conversion. The results of solid state fermentation demonstrated that the solid state fermentation process accompanied by simultaneous saccharification and fermentation. Copyright © 2012 Elsevier Ltd. All rights reserved.

  15. Integration of pulp and paper technology with bioethanol production

    PubMed Central

    2013-01-01

    Background Despite decades of work and billions of dollars of investments in laboratory and pilot plant projects, commercial production of cellulosic ethanol is only now beginning to emerge. Because of: (1)high technical risk coupled with; (2) high capital investment cost relative to ethanol product value, investors have not been able to justify moving forward with large scale projects on woody biomass. Results Both issues have been addressed by targeting pulp and paper industry processes for application in bioethanol production, in Greenfield, Repurpose and Co-Location scenarios. Processes commercially proven in hundreds of mills for many decades have been tailored to the recalcitrance of the biomass available. Economically feasible cellulosic bioethanol can be produced in Greenfield application with hardwoods, but not softwoods, using kraft mill equipment. Both types of wood species can profitably produce ethanol when kraft mill or newsprint assets are Repurposed to a biorefinery. A third situation which can generate high financial returns is where excess kraft pulp is available at a mill which has no excess drying capacity. Each scenario is supported by laboratory simulation, engineering and financial analysis. While pretreatment is critical to providing access of the biomass to enzymes, capital investment per unit of ethanol produced can be attractive, even if ethanol yield is modest. Conclusions Three guiding principles result in attractive economics: (1) re-use existing assets to the maximum extent; (2) keep the process as simple as possible; (3) match the recalcitrance of the biomass with the severity of the pretreatment. PMID:23356540

  16. Bioethanol production from rice straw by popping pretreatment

    PubMed Central

    2013-01-01

    Background Rice straw has considerable potential as a raw material for bioethanol production. Popping pretreatment of rice straw prior to downstream enzymatic hydrolysis and fermentation was found to increase cellulose to glucose conversion efficiency. The aim of this study was to investigate the influence of popping pretreatment and determine the optimal enzyme loading using a surface response design. Results The optimal doses of cellulase and xylanase enzymes were 23 FPU and 62 IU/g biomass, respectively. Using the optimized enzyme condition and popping pretreatment of rice straw (15% substrate loading, w/v), a sugar recovery of 0.567 g/g biomass (glucose; 0.394 g/g) was obtained in 48 h, which was significantly higher than that from untreated rice straw (total sugar recovery; 0.270 g/g biomass). Fermentation of the hydrolyzates by Saccharomyces cerevisiae resulted in 0.172 g ethanol/g biomass after 24 h, equivalent to 80.9% of the maximum theoretical yield (based on the amount of glucose in raw material). Changes in the chemical composition and surface area of rice straw were also investigated before and after popping pretreatment. The results showed little or no difference in chemical composition between the pretreated rice straw and the control. However, the surface area of pretreated rice straw increased twofold compared to the control. Conclusion Popping pretreatment of rice straw can effectively improve downstream saccharification and fermentation, important for bioethanol production. PMID:24286244

  17. An integrated process to produce bio-ethanol and xylooligosaccharides rich in xylobiose and xylotriose from high ash content waste wheat straw.

    PubMed

    Huang, Chen; Lai, Chenhuan; Wu, Xinxing; Huang, Yang; He, Juan; Huang, Caoxing; Li, Xin; Yong, Qiang

    2017-10-01

    A bio-refinery process of wheat straw pulping solid residue (waste wheat straw, WWS) was established by combining prewashing and liquid hot water pretreatment (LHWP). The results showed that employing a prewashing step prior to the LHWP remarkably improved enzymatic glucose yields from 39.7% to 76.6%. Moreover, after 96h simultaneous saccharification and fermentation (SSF), identical ethanol yields of 0.41g/g-cellulose were obtained despite varied solid loadings (5-30%). Beyond ethanol, enzymatic post-hydrolysis of the prehydrolyzate effectively increased xylobiose and xylotriose yields from 15mg/g-WWS and 14mg/g-WWS to 53mg/g-WWS and 20mg/g-WWS, respectively. For mass balance, about 10.9tons raw WWS will be consumed to produce 1ton ethanol, in addition to producing 614.8kg xylooligosaccharides (XOS) containing 334.3kg xylobiose and 124.8kg xylotriose. The results demonstrated that the integrated process for the WWS bio-refinery is promising, based on value-adding co-production in addition to robust ethanol yields. Copyright © 2017. Published by Elsevier Ltd.

  18. Microwave pretreatment of switchgrass for bioethanol production

    NASA Astrophysics Data System (ADS)

    Keshwani, Deepak Radhakrishin

    conditions, 82% glucose and 63% xylose yields were achieved for switchgrass, and 87% glucose and 59% xylose yields were achieved for coastal bermudagrass following enzymatic hydrolysis of the pretreated biomass. The optimum enzyme loadings were 15 FPU/g and 20 CBU/g for switchgrass and 10 FPU/g and 20 CBU/g for coastal bermudagrass. Dielectric properties for dilute sodium hydroxide solutions were measured and compared to solid loss, lignin reduction and reducing sugar levels in hydrolyzates. Results indicate that the dielectric loss tangent of alkali solutions is a potential indicator of the severity of microwave-based pretreatments. Modeling of pretreatment processes can be a valuable tool in process simulations of bioethanol production from lignocellulosic biomass. Chapter 4 discusses three different approaches that were used to model delignification and carbohydrate loss during microwave-based pretreatment of switchgrass: statistical linear regression modeling, kinetic modeling using a time-dependent rate coefficient, and a Mamdani-type fuzzy inference system. The dielectric loss tangent of the alkali reagent and pretreatment time were used as predictors in all models. The statistical linear regression model for delignification gave comparable root mean square error (RMSE) values for training and testing data and predictions were approximately within 1% of experimental values. The kinetic model for delignification and xylan loss gave comparable RMSE values for training and testing data sets and predictions were approximately within 2% of experimental values. The kinetic model for cellulose loss was not as effective and predictions were only within 5-7% of experimental values. The time-dependent rate coefficients of the kinetic models calculated from experimental data were consistent with the heterogeneity (or lack thereof) of individual biomass components. The Mamdani-type fuzzy inference system was shown to be an effective means to model pretreatment processes and gave

  19. Use of tropical maize for bioethanol production

    USDA-ARS?s Scientific Manuscript database

    Tropical maize is an alternative energy crop being considered as a feedstock for bioethanol production in the North Central and Midwest United States. Tropical maize is advantageous because it produces large amounts of soluble sugars in its stalks, creates a large amount of biomass, and requires lo...

  20. Toxicological challenges to microbial bioethanol production and strategies for improved tolerance

    DOE PAGES

    Akinsho, Hannah; Rydzak, Thomas; Borole, Abhijeet P.; ...

    2015-09-30

    Bioethanol production output has increased steadily over the last two decades and is now beginning to become competitive with traditional liquid transportation fuels due to advances in engineering, the identification of new production host organisms, and the development of novel biodesign strategies. A significant portion of these efforts has been dedicated to mitigating the toxicological challenges encountered across the bioethanol production process. From the release of potentially cytotoxic or inhibitory compounds from input feedstocks, through the metabolic co-synthesis of ethanol and potentially detrimental byproducts, and to the potential cytotoxicity of ethanol itself, each stage of bioethanol production requires the applicationmore » of genetic or engineering controls that ensure the host organisms remain healthy and productive to meet the necessary economies required for large scale production. In addition, as production levels continue to increase, there is an escalating focus on the detoxification of the resulting waste streams to minimize their environmental impact. Thus, this review will present the major toxicological challenges encountered throughout each stage of the bioethanol production process and the commonly employed strategies for reducing or eliminating potential toxic effects.« less

  1. Toxicological challenges to microbial bioethanol production and strategies for improved tolerance

    SciTech Connect

    Akinsho, Hannah; Rydzak, Thomas; Borole, Abhijeet P.; Ragauskas, Arthur; Close, Dan

    2015-09-30

    Bioethanol production output has increased steadily over the last two decades and is now beginning to become competitive with traditional liquid transportation fuels due to advances in engineering, the identification of new production host organisms, and the development of novel biodesign strategies. A significant portion of these efforts has been dedicated to mitigating the toxicological challenges encountered across the bioethanol production process. From the release of potentially cytotoxic or inhibitory compounds from input feedstocks, through the metabolic co-synthesis of ethanol and potentially detrimental byproducts, and to the potential cytotoxicity of ethanol itself, each stage of bioethanol production requires the application of genetic or engineering controls that ensure the host organisms remain healthy and productive to meet the necessary economies required for large scale production. In addition, as production levels continue to increase, there is an escalating focus on the detoxification of the resulting waste streams to minimize their environmental impact. Thus, this review will present the major toxicological challenges encountered throughout each stage of the bioethanol production process and the commonly employed strategies for reducing or eliminating potential toxic effects.

  2. Bioethanol Production from Hydrodictyon reticulatum by Fed-Batch Fermentation Using Saccharomyces cerevisiae KCTC7017.

    PubMed

    Kim, Seul Ki; Nguyen, Cuong Mai; Ko, Eun Hye; Kim, In-Chul; Kim, Jin-Seog; Kim, Jin-Cheol

    2017-06-28

    The aim of this study was to develop a potential process for bioethanol production from Hydrodictyon reticulatum (HR), a filamentous freshwater alga, using Saccharomyces cerevisiae (KCTC7017). From the sugar solutions prepared by the four different hydrolysis methods, bioethanol production ranged from 11.0 g/100 g dried material (acid hydrolysis) to 22.3 g/ 100 g dried material (enzymatic hydrolysis, EH). Bioethanol was fermented from a highly concentrated sugar solution obtained by a decompression-mediated (vacuum) enrichment method (VE). As the results, ethanol was more efficiently produced from HR when sugar solutions were concentrated by VE following EH (EH/VE). Using multiple feeding of the sugar solution prepared by EH/VE from HR, ethanol reached up to a concentration of 54.3 g/l, corresponding to 24.9 g/100 g dried material, which attained the economic level of product concentration (approximately 5%). The results indicate that by using HR, it is feasible to establish a bioethanol production process, which is effective for using microalgae as the raw material for ethanol production.

  3. Toxicological challenges to microbial bioethanol production and strategies for improved tolerance.

    PubMed

    Akinosho, Hannah; Rydzak, Thomas; Borole, Abhijeet; Ragauskas, Arthur; Close, Dan

    2015-12-01

    Bioethanol production output has increased steadily over the last two decades and is now beginning to become competitive with traditional liquid transportation fuels due to advances in engineering, the identification of new production host organisms, and the development of novel biodesign strategies. A significant portion of these efforts has been dedicated to mitigating the toxicological challenges encountered across the bioethanol production process. From the release of potentially cytotoxic or inhibitory compounds from input feedstocks, through the metabolic co-synthesis of ethanol and potentially detrimental byproducts, and to the potential cytotoxicity of ethanol itself, each stage of bioethanol production requires the application of genetic or engineering controls that ensure the host organisms remain healthy and productive to meet the necessary economies required for large scale production. In addition, as production levels continue to increase, there is an escalating focus on the detoxification of the resulting waste streams to minimize their environmental impact. This review will present the major toxicological challenges encountered throughout each stage of the bioethanol production process and the commonly employed strategies for reducing or eliminating potential toxic effects.

  4. The Influence of Emotions on Information Processing.

    ERIC Educational Resources Information Center

    Persson, Lars-Olof; Sjoberg, Lennart

    1978-01-01

    This report on the influence of emotional factors on cognitive processes and their importance to the design of man-machine systems intended to function under conditions of threat reviews the literature on stress and human performance, coping strategies, emotion theory, and individual differences in response to stress. A framework for relating…

  5. Airtight storage of moist wheat grain improves bioethanol yields

    PubMed Central

    Passoth, Volkmar; Eriksson, Anna; Sandgren, Mats; Ståhlberg, Jerry; Piens, Kathleen; Schnürer, Johan

    2009-01-01

    Background Drying is currently the most frequently used conservation method for cereal grain, which in temperate climates consumes a major part of process energy. Airtight storage of moist feed grain using the biocontrol yeast Pichia anomala as biopreservation agent can substantially reduce the process energy for grain storage. In this study we tested the potential of moist stored grain for bioethanol production. Results The ethanol yield from moist wheat was enhanced by 14% compared with the control obtained from traditionally (dry) stored grain. This enhancement was observed independently of whether or not P. anomala was added to the storage system, indicating that P. anomala does not impair ethanol fermentation. Starch and sugar analyses showed that during pre-treatment the starch of moist grain was better degraded by amylase treatment than that of the dry grain. Additional pre-treatment with cellulose and hemicellulose-degrading enzymes did not further increase the total ethanol yield. Sugar analysis after this pre-treatment showed an increased release of sugars not fermentable by Saccharomyces cerevisiae. Conclusion The ethanol yield from wheat grain is increased by airtight storage of moist grain, which in addition can save substantial amounts of energy used for drying the grain. This provides a new opportunity to increase the sustainability of bioethanol production. PMID:19695089

  6. Changes of Saccharomyces cerevisiae cell membrane components and promotion to ethanol tolerance during the bioethanol fermentation.

    PubMed

    Dong, Shi-Jun; Yi, Chen-Feng; Li, Hao

    2015-12-01

    During bioethanol fermentation process, Saccharomyces cerevisiae cell membrane might provide main protection to tolerate accumulated ethanol, and S. cerevisiae cells might also remodel their membrane compositions or structure to try to adapt to or tolerate the ethanol stress. However, the exact changes and roles of S. cerevisiae cell membrane components during bioethanol fermentation still remains poorly understood. This study was performed to clarify changes and roles of S. cerevisiae cell membrane components during bioethanol fermentation. Both cell diameter and membrane integrity decreased as fermentation time lasting. Moreover, compared with cells at lag phase, cells at exponential and stationary phases had higher contents of ergosterol and oleic acid (C18:1) but lower levels of hexadecanoic (C16:0) and palmitelaidic (C16:1) acids. Contents of most detected phospholipids presented an increase tendency during fermentation process. Increased contents of oleic acid and phospholipids containing unsaturated fatty acids might indicate enhanced cell membrane fluidity. Compared with cells at lag phase, cells at exponential and stationary phases had higher expressions of ACC1 and HFA1. However, OLE1 expression underwent an evident increase at exponential phase but a decrease at following stationary phase. These results indicated that during bioethanol fermentation process, yeast cells remodeled membrane and more changeable cell membrane contributed to acquiring higher ethanol tolerance of S. cerevisiae cells. These results highlighted our knowledge about relationship between the variation of cell membrane structure and compositions and ethanol tolerance, and would contribute to a better understanding of bioethanol fermentation process and construction of industrial ethanologenic strains with higher ethanol tolerance. Copyright © 2015 Elsevier Ltd. All rights reserved.

  7. Life cycle environmental impacts of bioethanol production from sugarcane molasses in Iran.

    PubMed

    Farahani, Saeid Shahvarooghi; Asoodar, Mohammad Amin

    2017-08-13

    In recent years, bioethanol from sugarcane molasses has been produced on an industrial scale in Iran. The aim of this study was to evaluate molasses-based bioethanol production from an environmental point of view. Data were collected from Debel Khazai agro-industry situated in southern region of Iran by using face-to-face interviews and annual statistics of 2010 to 2016 (6-year life cycle of sugarcane cultivation). Ten impact categories including abiotic depletion (AD), acidification (AC), eutrophication (EP), global warming potential (GWP), ozone layer depletion (OLD), human toxicity (HT), freshwater aquatic ecotoxicity (FE), marine aquatic ecotoxicity (ME), terrestrial ecotoxicity (TE), and photochemical oxidation (PO) were selected based on CML methodology. Inventory data for production of the inputs were taken from Ecoinvent, BUWAL 250, and IDMAT 2001 databases. The results revealed that in sugarcane cultivation process, electricity and trash burning were the most important contributors to all impact categories except OLD and TE. In industrial phase, natural gas had the highest contribution to the most impact categories. Greenhouse gas (GHG) emission for production of 1000 L molasses-based bioethanol was 1322.78 kg CO2 eq. By comparing total GHG emissions from 1000 L bioethanol to gasoline, the net avoided GHG emissions came out at 503.17 kg CO2 eq. According to results, it is clear that with increasing irrigation efficiency and improving performance of heating systems in industrial phase, environmental burdens would be significantly reduced.

  8. Integrated hydrolyzation and fermentation of sugar beet pulp to bioethanol.

    PubMed

    Rezić, Tonči; Oros, Damir; Marković, Iva; Kracher, Daniel; Ludwig, Roland; Santek, Božidar

    2013-09-28

    Sugar beet pulp is an abundant industrial waste material that holds a great potential for bioethanol production owing to its high content of cellulose, hemicelluloses, and pectin. Its structural and chemical robustness limits the yield of fermentable sugars obtained by hydrolyzation and represents the main bottleneck for bioethanol production. Physical (ultrasound and thermal) pretreatment methods were tested and combined with enzymatic hydrolysis by cellulase and pectinase to evaluate the most efficient strategy. The optimized hydrolysis process was combined with a fermentation step using a Saccharomyces cerevisiae strain for ethanol production in a single-tank bioreactor. Optimal sugar beet pulp conversion was achieved at a concentration of 60 g/l (39% of dry weight) and a bioreactor stirrer speed of 960 rpm. The maximum ethanol yield was 0.1 g ethanol/g of dry weight (0.25 g ethanol/g total sugar content), the efficiency of ethanol production was 49%, and the productivity of the bioprocess was 0.29 g/l·h, respectively.

  9. Long-term production of bioethanol in repeated-batch fermentation of microalgal biomass using immobilized Saccharomyces cerevisiae.

    PubMed

    El-Dalatony, Marwa M; Kurade, Mayur B; Abou-Shanab, Reda A I; Kim, Hoo; Salama, El-Sayed; Jeon, Byong-Hun

    2016-11-01

    Separate hydrolysis fermentation (SHF) and simultaneous saccharification fermentation (SSF) processes were studied for bioethanol production from microalgal biomass. SSF was selected as an efficient process to enhance the bioethanol yield through repeated-batches using immobilized yeast cells. Combined sonication and enzymatic hydrolysis of Chlamydomonas mexicana generated 10.5 and 8.48g/L of ethanol in SSF and SHF, respectively. Yeast utilized maximum portion of total reducing sugar (TRS) reaching a consumption efficiency of 91-98%. A bioethanol yield of 0.5g/g (88.2% of theoretical yield) and volumetric productivity of 0.22g/L/h was obtained after 48h of SSF. Immobilized yeast cells enabled repetitive production of ethanol for 7 cycles displaying a fermentation efficiency up to 79% for five consecutive cycles. The maximum ethanol production was 9.7g/L in 2nd-4th cycles. A total energy recovery of 85.81% was achieved from microalgal biomass in the form of bioethanol. Repeated-batch SSF demonstrated the possibility of cost-effective bioethanol production. Copyright © 2016 Elsevier Ltd. All rights reserved.

  10. Influence of collisional dephasing processes on superfluorescence

    NASA Astrophysics Data System (ADS)

    Maki, Jeffery J.; Malcuit, Michelle S.; Raymer, Michael G.; Boyd, Robert W.; Drummond, Peter D.

    1989-11-01

    We present a quantum-mechanical treatment of the influence of collisional dephasing processes on the statistical properties of superfluorescence (SF). The theory, which treats nonlinear propagation effects as well as quantum noise, shows how the nature of the cooperative emission process changes from that of SF to that of amplified spontaneous emission as the collisional dephasing rate is varied. The predictions of how the SF delay time varies with the collisional dephasing rate are in good agreement with the results of a recent experiment [M. S. Malcuit, J. J. Maki, D. J. Simkin, and R. W. Boyd, Phys. Rev. Lett. 59, 1189 (1987)].

  11. Direct Conversion of Bio-ethanol to Isobutene on Nanosized ZnxZryOz Mixed Oxides with Balanced Acid–Base Sites

    SciTech Connect

    Sun, Junming; Zhu, Kake; Gao, Feng; Wang, Chong M.; Liu, Jun; Peden, Charles HF; Wang, Yong

    2011-06-17

    Bio-mass conversion has attracted increasing research interests to produce bio-fuels with bio-ethanol being a major product. Development of advanced processes to further upgrade bio-ethanol to other value added fuels or chemicals are pivotal to improving the economics of biomass conversion and deversifying the utilization of biomass resources. In this paper, for the first time, we report the direct conversion of bio-ethanol to isobutene with high yield (~83%) on a multifunctional ZnxZryOz mixed oxide with a dedicated balance of surface acid-base properties. This work illustrates the significance of rational design of a multifunctional mixed oxide catalyst for one step bio-ethanol conversion to a value-added intermediate, isobutene, for chemical and fuel production. This work was supported by the US Department of Energy Basic Energy Sciences' Chemical Sciences, Geosciences & Biosciences Division. Pacific Northwest National Laboratory is operated by Battelle for the US Department of Energy.

  12. Enzymes, Energy, and the Environment: A Strategic Perspective on the U.S. Department of Energy's Research and Development Activities for Bioethanol.

    PubMed

    Sheehan; Himmel

    1999-10-01

    For well over one hundred years, researchers around the world have pursued ways to make ethanol from biomass such as wood, grasses, and waste materials. To distinguish it from ethanol made from starch and sugars in traditional agricultural crops, we refer to ethanol made from biomass as "bioethanol." The effort to develop bioethanol technology gained significant momentum in the late 1970s as a result of the energy crises that occurred in that decade. This article briefly reviews the broader history of bioethanol technology development. With this as a background, we focus our attention on the strategic thinking behind the U.S. Department of Energy's Bioethanol Program, which envisions remarkable advances in cellulase enzyme research and as the basis for significant future process cost reductions.

  13. Bioethanol production from the macroalgae Sargassum spp.

    PubMed

    Borines, Myra G; de Leon, Rizalinda L; Cuello, Joel L

    2013-06-01

    Macroalgae, an abundant and carbon-neutral renewable resource, with several species rich in carbohydrates are suitable for bioethanol production. This study focused on the pretreatment, enzyme saccharification and fermentation of Sargassum spp., a brown macroalgae for bioethanol production. The optimal acid pretreatment condition achieved in terms of glucose and reducing sugar yields was 3.4-4.6% (w/v) H2SO4 concentration, 115°C and 1.50h. The pretreated biomass was hydrolyzed with cellulase enzyme system supplemented with β-glucosidase. After fermentation by Saccharomyces cerevisiae at 40°C, pH of 4.5 for 48 h, the ethanol conversion rate of the enzyme hydrolysate reached 89%, which was markedly higher than the theoretical yield of 51% based on glucose as substrate. Since all the glucose was consumed during fermentation, other sugar sources might be present in the hydrolysate. The macroalgae, Sargassum spp., showed significant potential as a renewable feedstock for the production of bioethanol.

  14. Influence of Milling Process on Efavirenz Solubility.

    PubMed

    Zaini, Erizal; Wahyu, Deni; Octavia, Maria Dona; Fitriani, Lili

    2017-01-01

    The aim of this study was to investigate the influence of the milling process on the solubility of efavirenz. Milling process was done using Nanomilling for 30, 60, and 180 min. Intact and milled efavirenz were characterized by powder X-ray diffraction, scanning electron microscopy (SEM), spectroscopy infrared (IR), differential scanning calorimetry (DSC), and solubility test. The X-ray diffractogram showed a decline on peak intensity of milled efavirenz compared to intact efavirenz. The SEM graph depicted the change from crystalline to amorphous habit after milling process. The IR spectrum showed there was no difference between intact and milled efavirenz. Thermal analysis which performed by DSC showed a reduction on endothermic peak after milling process which related to decreasing of crystallinity. Solubility test of intact and milled efavirenz was conducted in distilled water free CO2 with 0.25% sodium lauryl sulfate media and measured using high-performance liquid chromatography method with acetonitrile: distilled water (80:20) as mobile phases. The solubility was significantly increased (P < 0.05) after milling processes, which the intact efavirenz was 27.12 ± 2.05, while the milled efavirenz for 30, 60, and 180 min were 75.53 ± 1.59, 82.34 ± 1.23, and 104.75 ± 0.96 μg/mL, respectively. Based on the results, the solubility of efavirenz improved after milling process.

  15. An organic acid-tolerant HAA1-overexpression mutant of an industrial bioethanol strain of Saccharomyces cerevisiae and its application to the production of bioethanol from sugarcane molasses.

    PubMed

    Inaba, Takuya; Watanabe, Daisuke; Yoshiyama, Yoko; Tanaka, Koichi; Ogawa, Jun; Takagi, Hiroshi; Shimoi, Hitoshi; Shima, Jun

    2013-12-30

    Bacterial contamination is known as a major cause of the reduction in ethanol yield during bioethanol production by Saccharomyces cerevisiae. Acetate is an effective agent for the prevention of bacterial contamination, but it negatively affects the fermentation ability of S. cerevisiae. We have proposed that the combined use of organic acids including acetate and lactate and yeast strains tolerant to organic acids may be effective for the elimination of principally lactic acid bacterial (LAB) contamination. In a previous study employing laboratory S. cerevisiae strains, we showed that overexpression of the HAA1 gene, which encodes a transcriptional activator, could be a useful molecular breeding method for acetate-tolerant yeast strains. In the present study, we constructed a HAA1-overexpressing diploid strain (MATa/α, named ER HAA1-OP) derived from the industrial bioethanol strain Ethanol Red (ER). ER HAA1-OP showed tolerance not only to acetate but also to lactate, and this tolerance was dependent on the increased expression of HAA1 gene. The ethanol production ability of ER HAA1-OP was almost equivalent to that of the parent strain during the bioethanol production process from sugarcane molasses in the absence of acetate. The addition of acetate at 0.5% (w/v, pH 4.5) inhibited the fermentation ability of the parent strain, but such an inhibition was not observed in the ethanol production process using ER HAA1-OP.

  16. An organic acid-tolerant HAA1-overexpression mutant of an industrial bioethanol strain of Saccharomyces cerevisiae and its application to the production of bioethanol from sugarcane molasses

    PubMed Central

    2013-01-01

    Bacterial contamination is known as a major cause of the reduction in ethanol yield during bioethanol production by Saccharomyces cerevisiae. Acetate is an effective agent for the prevention of bacterial contamination, but it negatively affects the fermentation ability of S. cerevisiae. We have proposed that the combined use of organic acids including acetate and lactate and yeast strains tolerant to organic acids may be effective for the elimination of principally lactic acid bacterial (LAB) contamination. In a previous study employing laboratory S. cerevisiae strains, we showed that overexpression of the HAA1 gene, which encodes a transcriptional activator, could be a useful molecular breeding method for acetate-tolerant yeast strains. In the present study, we constructed a HAA1-overexpressing diploid strain (MATa/α, named ER HAA1-OP) derived from the industrial bioethanol strain Ethanol Red (ER). ER HAA1-OP showed tolerance not only to acetate but also to lactate, and this tolerance was dependent on the increased expression of HAA1 gene. The ethanol production ability of ER HAA1-OP was almost equivalent to that of the parent strain during the bioethanol production process from sugarcane molasses in the absence of acetate. The addition of acetate at 0.5% (w/v, pH 4.5) inhibited the fermentation ability of the parent strain, but such an inhibition was not observed in the ethanol production process using ER HAA1-OP. PMID:24373204

  17. Consolidated bioprocessing for bioethanol production using Saccharomyces cerevisiae.

    PubMed

    van Zyl, Willem H; Lynd, Lee R; den Haan, Riaan; McBride, John E

    2007-01-01

    Consolidated bioprocessing (CBP) of lignocellulose to bioethanol refers to the combining of the four biological events required for this conversion process (production of saccharolytic enzymes, hydrolysis of the polysaccharides present in pretreated biomass, fermentation of hexose sugars, and fermentation of pentose sugars) in one reactor. CBP is gaining increasing recognition as a potential breakthrough for low-cost biomass processing. Although no natural microorganism exhibits all the features desired for CBP, a number of microorganisms, both bacteria and fungi, possess some of the desirable properties. This review focuses on progress made toward the development of baker's yeast (Saccharomyces cerevisiae) for CBP. The current status of saccharolytic enzyme (cellulases and hemicellulases) expression in S. cerevisiae to complement its natural fermentative ability is highlighted. Attention is also devoted to the challenges ahead to integrate all required enzymatic activities in an industrial S. cerevisiae strain(s) and the need for molecular and selection strategies pursuant to developing a yeast capable of CBP.

  18. Protein Molecular Structures and Protein Fraction Profiles of New Co-Products of BioEthanol Production: A Novel Approach

    SciTech Connect

    Yu, P.; Niu, Z; Damiran, D

    2010-01-01

    The objectives of this study were to determine the protein molecular structures of the new coproducts from bioethanol production, quantify protein structure amide I to II and {alpha}-helix to {beta}-sheet spectral peak intensity ratio, and illustrate multivariate molecular spectral analyses as a novel research tool for rapid characterization of protein molecular structures in bioethonal bioproducts. The study demonstrated that the grains had a significantly higher ratio of {alpha}-helix to {beta}-sheet in the protein structure than their coproducts produced from bioethanol processing (1.38 vs 1.03, P < 0.05). There were significant differences between wheat and corn (1.47 vs 1.29, P < 0.05) but no difference between wheat dried distiller grains with solubles (DDGS) and corn DDGS (1.04 vs 1.03, P > 0.05). The grains had a significantly higher ratio of protein amide I to II in the protein structure than their coproducts produced from bioethanol processing (4.58 vs 2.84, P < 0.05). There were no significant differences between wheat and corn (4.61 vs 4.56, P > 0.05), but there were significant differences between wheat DDGS and corn DDGS (3.08 vs 2.21, P < 0.05). This preliminary study indicated that bioethanol processing changes protein molecular structures, compared with original grains. Further study is needed with a large set of the new bioethanol coproducts to quantify protein molecular structures ({alpha}-helix to {beta}-sheet ratio; amide I to II ratio) of the bioethanol coproducts in relation to nutrient supply and availability in animals.

  19. Bioethanol production from recovered napier grass with heavy metals.

    PubMed

    Ko, Chun-Han; Yu, Fan-Chun; Chang, Fang-Chih; Yang, Bing-Yuan; Chen, Wen-Hua; Hwang, Wen-Song; Tu, Ta-Chih

    2017-05-11

    Using plants to absorb and accumulate heavy metals from polluted soil, followed by the recycling of explants containing heavy metals, can help achieve the goal of reverting contaminated soil to low heavy-metal content soil. However, the re-use of recovered explants can also be problematic. Meanwhile, bioethanol has become a popular energy source. In this study, napier grass was used for the remediation of soil contaminated with heavy metals (artificially contaminated soil). The influence of bioethanol production from napier grass after phytoremediation was also investigated. The concentration of Zn, Cd, and Cr in the contaminated soil was 1000, 100, and 250 mg/kg, respectively. After napier grass phytoremediation, the concentration (dry biomass) of Zn, Cd, and Cr in the explants was 2701.97 ± 173.49, 6.1 ± 2.3, and 74.24 ± 1.42 mg/kg, respectively. Biomass production in the unpolluted soil was 861.13 ± 4.23 g. The biomass production ratio in high Zn-polluted soil was only 3.89%, while it was 4.68% for Cd and 21.4% for Cr. The biomass obtained after napier grass phytoremediation was pretreated using the steam explosion conditions of 180 °C, for 10 min, with 1.5% H2SO2, followed by enzymatic hydrolysis. The efficiency of enzymatic hydrolysis for Zn-polluted biomass was 90% of the unpolluted biomass, while it was 77% for Cd, and approximately the same for Cr. The fermentation efficiency of the heavy-metal-containing biomass was higher than the control biomass. The fermentation ethanol concentration obtained was 8.69-12.68, 13.03-15.50, and 18.48-19.31 g/L in Zn, Cd, and Cr environments, respectively. Results show that the heavy metals had a positive effect on bacteria fermentation. However, the fermentation efficiency was lower for biomass with severe heavy metal pollution. Thus, the utilization of napier grass phytoremediation for bioethanol production has a positive effect on the sustainability of environmental resources. Copyright © 2017

  20. Simultaneous detection of the absorption spectrum and refractive index ratio with a spectrophotometer: monitoring contaminants in bioethanol

    NASA Astrophysics Data System (ADS)

    Kontturi, V.; Hyvärinen, S.; García, A.; Carmona, R.; Murzin, D. Yu; Mikkola, J.-P.; Peiponen, K.-E.

    2011-05-01

    The optical properties of a biofuel resulting from the fungi-treated lignocellulosic biomass in an ethanol matrix were studied. The matrix simulates the case that the bioethanol is contaminated by sugars, water and colour pigments that reduce the quality of the biofuel and compromise the combustion process. It is suggested that by applying a spectrophotometer only, it is possible to obtain valid information, i.e. the spectral features of the contaminants as well as the refractive index ratio of bioethanol. This allows for simultaneous purity and density detection of biomass-derived liquids or liquid biofuels, in comparison to a reference representing an ideal bioethanol (pure ethyl alcohol, ethanol of 99.5% purity (v/v)).

  1. Regulation of Lactobacillus plantarum contamination on the carbohydrate and energy related metabolisms of Saccharomyces cerevisiae during bioethanol fermentation.

    PubMed

    Dong, Shi-Jun; Lin, Xiang-Hua; Li, Hao

    2015-11-01

    During the industrial bioethanol fermentation, Saccharomyces cerevisiae cells are often stressed by bacterial contaminants, especially lactic acid bacteria. Generally, lactic acid bacteria contamination can inhibit S. cerevisiae cell growth through secreting lactic acid and competing with yeast cells for micronutrients and living space. However, whether are there still any other influences of lactic acid bacteria on yeast or not? In this study, Lactobacillus plantarum ATCC 8014 was co-cultivated with S. cerevisiae S288c to mimic the L. plantarum contamination in industrial bioethanol fermentation. The contaminative L. plantarum-associated expression changes of genes involved in carbohydrate and energy related metabolisms in S. cerevisiae cells were determined by quantitative real-time polymerase chain reaction to evaluate the influence of L. plantarum on carbon source utilization and energy related metabolism in yeast cells during bioethanol fermentation. Contaminative L. plantarum influenced the expression of most of genes which are responsible for encoding key enzymes involved in glucose related metabolisms in S. cerevisiae. Specific for, contaminated L. plantarum inhibited EMP pathway but promoted TCA cycle, glyoxylate cycle, HMP, glycerol synthesis pathway, and redox pathway in S. cerevisiae cells. In the presence of L. plantarum, the carbon flux in S. cerevisiae cells was redistributed from fermentation to respiratory and more reducing power was produced to deal with the excess NADH. Moreover, L. plantarum contamination might confer higher ethanol tolerance to yeast cells through promoting accumulation of glycerol. These results also highlighted our knowledge about relationship between contaminative lactic acid bacteria and S. cerevisiae during bioethanol fermentation.

  2. Hydrogen-based power generation from bioethanol steam reforming

    SciTech Connect

    Tasnadi-Asztalos, Zs. Cormos, C. C. Agachi, P. S.

    2015-12-23

    This paper is evaluating two power generation concepts based on hydrogen produced from bioethanol steam reforming at industrial scale without and with carbon capture. The power generation from bioethanol conversion is based on two important steps: hydrogen production from bioethanol catalytic steam reforming and electricity generation using a hydrogen-fuelled gas turbine. As carbon capture method to be assessed in hydrogen-based power generation from bioethanol steam reforming, the gas-liquid absorption using methyl-di-ethanol-amine (MDEA) was used. Bioethanol is a renewable energy carrier mainly produced from biomass fermentation. Steam reforming of bioethanol (SRE) provides a promising method for hydrogen and power production from renewable resources. SRE is performed at high temperatures (e.g. 800-900°C) to reduce the reforming by-products (e.g. ethane, ethene). The power generation from hydrogen was done with M701G2 gas turbine (334 MW net power output). Hydrogen was obtained through catalytic steam reforming of bioethanol without and with carbon capture. For the evaluated plant concepts the following key performance indicators were assessed: fuel consumption, gross and net power outputs, net electrical efficiency, ancillary consumptions, carbon capture rate, specific CO{sub 2} emission etc. As the results show, the power generation based on bioethanol conversion has high energy efficiency and low carbon footprint.

  3. Hydrogen-based power generation from bioethanol steam reforming

    NASA Astrophysics Data System (ADS)

    Tasnadi-Asztalos, Zs.; Cormos, C. C.; Agachi, P. S.

    2015-12-01

    This paper is evaluating two power generation concepts based on hydrogen produced from bioethanol steam reforming at industrial scale without and with carbon capture. The power generation from bioethanol conversion is based on two important steps: hydrogen production from bioethanol catalytic steam reforming and electricity generation using a hydrogen-fuelled gas turbine. As carbon capture method to be assessed in hydrogen-based power generation from bioethanol steam reforming, the gas-liquid absorption using methyl-di-ethanol-amine (MDEA) was used. Bioethanol is a renewable energy carrier mainly produced from biomass fermentation. Steam reforming of bioethanol (SRE) provides a promising method for hydrogen and power production from renewable resources. SRE is performed at high temperatures (e.g. 800-900°C) to reduce the reforming by-products (e.g. ethane, ethene). The power generation from hydrogen was done with M701G2 gas turbine (334 MW net power output). Hydrogen was obtained through catalytic steam reforming of bioethanol without and with carbon capture. For the evaluated plant concepts the following key performance indicators were assessed: fuel consumption, gross and net power outputs, net electrical efficiency, ancillary consumptions, carbon capture rate, specific CO2 emission etc. As the results show, the power generation based on bioethanol conversion has high energy efficiency and low carbon footprint.

  4. Do lipids influence the allergic sensitization process?

    PubMed Central

    Bublin, Merima; Eiwegger, Thomas; Breiteneder, Heimo

    2014-01-01

    Allergic sensitization is a multifactorial process that is not only influenced by the allergen and its biological function per se but also by other small molecular compounds, such as lipids, that are directly bound as ligands by the allergen or are present in the allergen source. Several members of major allergen families bind lipid ligands through hydrophobic cavities or electrostatic or hydrophobic interactions. These allergens include certain seed storage proteins, Bet v 1–like and nonspecific lipid transfer proteins from pollens and fruits, certain inhalant allergens from house dust mites and cockroaches, and lipocalins. Lipids from the pollen coat and furry animals and the so-called pollen-associated lipid mediators are codelivered with the allergens and can modulate the immune responses of predisposed subjects by interacting with the innate immune system and invariant natural killer T cells. In addition, lipids originating from bacterial members of the pollen microbiome contribute to the outcome of the sensitization process. Dietary lipids act as adjuvants and might skew the immune response toward a TH2-dominated phenotype. In addition, the association with lipids protects food allergens from gastrointestinal degradation and facilitates their uptake by intestinal cells. These findings will have a major influence on how allergic sensitization will be viewed and studied in the future. PMID:24880633

  5. Do lipids influence the allergic sensitization process?

    PubMed

    Bublin, Merima; Eiwegger, Thomas; Breiteneder, Heimo

    2014-09-01

    Allergic sensitization is a multifactorial process that is not only influenced by the allergen and its biological function per se but also by other small molecular compounds, such as lipids, that are directly bound as ligands by the allergen or are present in the allergen source. Several members of major allergen families bind lipid ligands through hydrophobic cavities or electrostatic or hydrophobic interactions. These allergens include certain seed storage proteins, Bet v 1-like and nonspecific lipid transfer proteins from pollens and fruits, certain inhalant allergens from house dust mites and cockroaches, and lipocalins. Lipids from the pollen coat and furry animals and the so-called pollen-associated lipid mediators are codelivered with the allergens and can modulate the immune responses of predisposed subjects by interacting with the innate immune system and invariant natural killer T cells. In addition, lipids originating from bacterial members of the pollen microbiome contribute to the outcome of the sensitization process. Dietary lipids act as adjuvants and might skew the immune response toward a TH2-dominated phenotype. In addition, the association with lipids protects food allergens from gastrointestinal degradation and facilitates their uptake by intestinal cells. These findings will have a major influence on how allergic sensitization will be viewed and studied in the future.

  6. Integrated bioethanol and biomanure production from potato waste.

    PubMed

    Chintagunta, Anjani Devi; Jacob, Samuel; Banerjee, Rintu

    2016-03-01

    Disposal of potato processing waste and the problem of pollution associated with it is a vital issue that is being faced by the potato processing plants. The conventional peeling methods presently followed in the processing plants for removing the potato peel, also result in the loss of some portion of the mash which is rich in starch. Indiscriminate discharge of the waste causes detrimental effects in the environment, so this problem can be resolved by successful utilization of the waste for the generation of value added products. Hence, the present work focuses on integrated production of bioethanol and biomanure to utilize the waste completely leading to zero waste generation. The first part of the work describes a comparative study of ethanol production from potato peel and mash wastes by employing co-culture of Aspergillus niger and Saccharomyces cerevisiae at various incubation time (24-120 h) instead of application of enzymes. The solid state fermentation of potato peel and mash inoculated with co-culture, resulted in bioethanol production of 6.18% (v/v) and 9.30% (v/v) respectively. In the second part of the work, the residue obtained after ethanol production was inoculated with seven different microorganisms (Nostoc muscorum, Fischerella muscicola, Anabaena variabilis, Aulosira fertilissima, Cylindrospermum muscicola, Azospirillium lipoferum, Azotobacter chroococcum) and mixture of all the organisms in equal ratio for nitrogen (N), phosphorous (P) and potassium (K) enrichment. Among them, A. variabilis was found to enrich N, P and K content of the residue by nearly 7.66, 21.66 and 15 fold than that of the initial content, ultimately leading to improved N:P:K ratio of approximately 2:1:1. The application of simultaneous saccharification and fermentation (SSF) for the conversion of potato waste to ethanol and enrichment of residue obtained after ethanol production with microorganisms to be used as manure envisages environmental sustainability.

  7. Development of Education Program Applying Internal Combustion Engine with Bioethanol as Fuel

    NASA Astrophysics Data System (ADS)

    Utsumi, Noah; Yoshida, Masashi; Inada, Yuji

    One of the ways to mitigate global warming is to reduce carbon dioxide emissions. In Japan, carbon dioxide emissions from vehicles, which run on fossil fuels, account for about 1/4 of the total carbon dioxide emissions. In this study, we applied a commercial engine, and remodeled the engine which could work using bioethanol as a fuel. We subsequently examined the influence of exhaust emission of the engine with the bioethanol and documented the entire study as teaching materials, including the remodeling method. Next, we began our mechanical engineering courses at the university by using the teaching materials in this study as introductory education, with the aim of stimulating the interest of the students. We then developed an education program for the students.

  8. A simple and effective set of PCR-based molecular markers for the monitoring of the Saccharomyces cerevisiae cell population during bioethanol fermentation.

    PubMed

    Carvalho-Netto, Osmar V; Carazzolle, Marcelo F; Rodrigues, Aline; Bragança, Welbe O; Costa, Gustavo G L; Argueso, Juan Lucas; Pereira, Gonçalo A G

    2013-12-01

    One of the defining features of the fermentation process used in the production of bioethanol from sugarcane feedstock is the dynamic nature of the yeast population. Minisatellite molecular markers are particularly useful for monitoring yeast communities because they produce polymorphic PCR products that typically display wide size variations. We compared the coding sequences derived from the genome of the sugarcane bioethanol strain JAY270/PE-2 to those of the reference Saccharomyces cerevisiae laboratory strain S288c, and searched for genes containing insertion or deletion polymorphisms larger than 24 bp. We then designed oligonucleotide primers flanking nine of these sites, and used them to amplify differentially sized PCR products. We analyzed the banding patterns in the most widely adopted sugarcane bioethanol strains and in several indigenous yeast contaminants, and found that our marker set had very good discriminatory power. Subsequently, these markers were used to successfully monitor the yeast cell populations in six sugarcane bioethanol distilleries. Additionally, we showed that most of the markers described here are also polymorphic among strains unrelated to bioethanol production, suggesting that they may be applied universally in S. cerevisiae. Because the relatively large polymorphisms are detectable in conventional agarose gels, our method is well suited to modestly equipped on-site laboratories at bioethanol distilleries, therefore providing both cost and time savings.

  9. Developmental influences of science process skill instruction

    NASA Astrophysics Data System (ADS)

    Scharmann, Lawrence C.

    Science educators have claimed that well-conceived instructional strategies and curricular sequences, emphasizing the process aspects of science, will foster an understanding of the nature of science. Furthermore, a process emphasis on science has been cited for its ability to promote logical thinking skill, develop a locus of control shift, and enhance science content acquisition. The intent of this investigation was to examine the purported influence and developmental nature of a science process emphasis during a given semester of study, as well as over extended curricular sequences, each sequence being representative of three recognized preservice elementary science teacher preparatory programs. Data were collected from 135 elementary preservice teachers enrolled in science teaching methods courses at the endpoint of one of three sequences: (a) introductory process instruction with three subsequent semesters of integrated science content and teaching methods, (b) process instruction with separate subsequent content and teaching methods, and (c) only science content with subsequent teaching methods. Another 29 preservice teachers, assessed prior to entry into instructional sequences, provided a cross-sectional sample for examining developmental changes in locus of control, logical thinking, nature of science, and science content knowledge. Statistical procedures included Kruskal-Wallis ANOVA and Wilcoxon tests. Results indicated that a one-semester process skills course was influential in developing a basis for science content acquisition and in fostering an understanding of the nature of science. Results further indicate that expected additional gains are significant in science content acquisition through matriculation in an extended curricular sequence. Implications for science educators are discussed.

  10. Earthing the Human Body Influences Physiologic Processes

    PubMed Central

    Sokal, Karol

    2011-01-01

    Abstract Objectives This study was designed to answer the question: Does the contact of the human organism with the Earth via a copper conductor affect physiologic processes? Subjects and experiments Five (5) experiments are presented: experiment 1—effect of earthing on calcium–phosphate homeostasis and serum concentrations of iron (N = 84 participants); experiment 2—effect of earthing on serum concentrations of electrolytes (N = 28); experiment 3—effect of earthing on thyroid function (N = 12); experiment 4—effect of earthing on glucose concentration (N = 12); experiment 5—effect of earthing on immune response to vaccine (N = 32). Subjects were divided into two groups. One (1) group of people was earthed, while the second group remained without contact with the Earth. Blood and urine samples were examined. Results Earthing of an electrically insulated human organism during night rest causes lowering of serum concentrations of iron, ionized calcium, inorganic phosphorus, and reduction of renal excretion of calcium and phosphorus. Earthing during night rest decreases free tri-iodothyronine and increases free thyroxine and thyroid-stimulating hormone. The continuous earthing of the human body decreases blood glucose in patients with diabetes. Earthing decreases sodium, potassium, magnesium, iron, total protein, and albumin concentrations while the levels of transferrin, ferritin, and globulins α1, α2, β, and γ increase. These results are statistically significant. Conclusions Earthing the human body influences human physiologic processes. This influence is observed during night relaxation and during physical activity. Effect of the earthing on calcium–phosphate homeostasis is the opposite of that which occurs in states of weightlessness. It also increases the activity of catabolic processes. It may be the primary factor regulating endocrine and nervous systems. PMID:21469913

  11. Earthing the human body influences physiologic processes.

    PubMed

    Sokal, Karol; Sokal, Pawel

    2011-04-01

    This study was designed to answer the question: Does the contact of the human organism with the Earth via a copper conductor affect physiologic processes? Subjects and experiments: Five (5) experiments are presented: experiment 1-effect of earthing on calcium-phosphate homeostasis and serum concentrations of iron (N = 84 participants); experiment 2-effect of earthing on serum concentrations of electrolytes (N = 28); experiment 3-effect of earthing on thyroid function (N = 12); experiment 4-effect of earthing on glucose concentration (N = 12); experiment 5-effect of earthing on immune response to vaccine (N = 32). Subjects were divided into two groups. One (1) group of people was earthed, while the second group remained without contact with the Earth. Blood and urine samples were examined. Earthing of an electrically insulated human organism during night rest causes lowering of serum concentrations of iron, ionized calcium, inorganic phosphorus, and reduction of renal excretion of calcium and phosphorus. Earthing during night rest decreases free tri-iodothyronine and increases free thyroxine and thyroid-stimulating hormone. The continuous earthing of the human body decreases blood glucose in patients with diabetes. Earthing decreases sodium, potassium, magnesium, iron, total protein, and albumin concentrations while the levels of transferrin, ferritin, and globulins α1, α2, β, and γ increase. These results are statistically significant. Earthing the human body influences human physiologic processes. This influence is observed during night relaxation and during physical activity. Effect of the earthing on calcium-phosphate homeostasis is the opposite of that which occurs in states of weightlessness. It also increases the activity of catabolic processes. It may be the primary factor regulating endocrine and nervous systems.

  12. Combined acid/alkaline-peroxide pretreatment of olive tree biomass for bioethanol production.

    PubMed

    Martínez-Patiño, José Carlos; Ruiz, Encarnación; Romero, Inmaculada; Cara, Cristóbal; López-Linares, Juan Carlos; Castro, Eulogio

    2017-09-01

    Olive tree biomass (OTB) can be used for producing second generation bioethanol. In this work, extracted OTB was subjected to fractionation using a sequential acid/alkaline oxidative pretreatment. In the first acid stage, the effects of sulfuric acid concentration and reaction times at 130°C were investigated. Up to 71% solubilization of hemicellulosic sugars was achieved under optimized conditions (2.4% H2SO4, 84min). In the second stage, the influence of hydrogen peroxide concentration and process time were evaluated at 80°C. Approximately 80% delignification was achieved under the best operational conditions (7% H2O2, 90min) within the experimental range studied. This pretreatment produced a substrate with 72% cellulose that was highly accessible to enzymatic attack, yielding 82g glucose/100g glucose in delignified OTB. Ethanol production from both hemicellulosic sugars solubilized in the acid pretreatment and glucose from enzymatic hydrolysis of delignified OTB yielded 15g ethanol/100g OTB. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Production of bioethanol as useful biofuel through the bioconversion of water hyacinth (Eichhornia crassipes).

    PubMed

    Das, Arpan; Ghosh, Priyanka; Paul, Tanmay; Ghosh, Uma; Pati, Bikas Ranjan; Mondal, Keshab Chandra

    2016-06-01

    Water hyacinth (Eichhornia crassipes) represents a promising candidate for fuel ethanol production in tropical countries because of their high availability and high biomass yield. Bioconversion of such biomass to bioethanol could be wisely managed through proper technological approach. In this work, pretreatment of water hyacinth (10 %, w/v) with dilute sulfuric acid (2 %, v/v) at high temperature and pressure was integrated in the simulation and economic assessment of the process for further enzymatic saccharification was studied. The maximum sugar yield (425.6 mg/g) through enzymatic saccharification was greatly influenced by the solid content (5 %), cellulase load (30 FPU), incubation time (24 h), temperature (50 °C), and pH (5.5) of the saccharifying medium. Central composite design optimized an ethanol production of 13.6 mg/ml though a mixed fermentation by Saccharomyces cerevisiae (MTCC 173) and Zymomonas mobilis (MTCC 2428). Thus the experiment imparts an economic value to water hyacinths that are cleared from choking waterways.

  14. Effect of double-step steam explosion pretreatment in bioethanol production from softwood.

    PubMed

    Cotana, Franco; Cavalaglio, Gianluca; Gelosia, Mattia; Coccia, Valentina; Petrozzi, Alessandro; Nicolini, Andrea

    2014-09-01

    The study investigated the production of bioethanol from softwood, in particular pine wood chip. The steam explosion pretreatment was largely investigated, evaluating also the potential use of a double-step process to increase ethanol production through the use of both solid and liquid fraction after the pretreatment. The pretreatment tests were carried out at different conditions, determining the composition of solid and liquid fraction and steam explosion efficiency. The enzymatic hydrolysis was carried out with Ctec2 enzyme while the fermentation was carried out using Saccharomyces Cerevisiae yeast "red ethanol". It was found that the best experimental result was obtained for a single-step pretreated sample (10.6 g of ethanol/100 g of initial biomass dry basis) for a 4.53 severity. The best double-step overall performance was equal to 8.89 g ethanol/100 g of initial biomass dry basis for a 4.27 severity. The enzymatic hydrolysis strongly depended on the severity of the pretreatment while the fermentation efficiency was mainly influenced by the concentration of the inhibitors. The ethanol enhancing potential of a double-step steam explosion could slightly increase the ethanol production compared to single-step potential.

  15. Development of yeast cell factories for consolidated bioprocessing of lignocellulose to bioethanol through cell surface engineering.

    PubMed

    Hasunuma, Tomohisa; Kondo, Akihiko

    2012-01-01

    To build an energy and material secure future, a next generation of renewable fuels produced from lignocellulosic biomass is required. Although lignocellulosic biomass, which represents an abundant, inexpensive and renewable source for bioethanol production, is of great interest as a feedstock, the complicated ethanol production processes involved make the cost of producing bioethanol from it higher compared to corn starch and cane juice. Therefore, consolidated bioprocessing (CBP), which combines enzyme production, saccharification and fermentation in a single step, has gained increased recognition as a potential bioethanol production system. CBP requires a highly engineered microorganism developed for several different process-specific characteristics. The dominant strategy for engineering a CBP biocatalyst is to express multiple components of a cellulolytic system from either fungi or bacteria in the yeast Saccharomyces cerevisiae. The development of recombinant yeast strains displaying cellulases and hemicellulases on the cell surface represents significant progress toward realization of CBP. Regardless of the process used for biomass hydrolysis, CBP-enabling microorganisms encounter a variety of toxic compounds produced during biomass pretreatment that inhibit microbial growth and ethanol yield. Systems biology approaches including disruptome screening, transcriptomics, and metabolomics have been recently exploited to gain insight into the molecular and genetic traits involved in tolerance and adaptation to the fermentation inhibitors. In this review, we focus on recent advances in development of yeast strains with both the ability to directly convert lignocellulosic material to ethanol and tolerance in the harsh environments containing toxic compounds in the presence of ethanol.

  16. Optimization study on the hydrogen peroxide pretreatment and production of bioethanol from seaweed Ulva prolifera biomass.

    PubMed

    Li, Yinping; Cui, Jiefen; Zhang, Gaoli; Liu, Zhengkun; Guan, Huashi; Hwang, Hueymin; Aker, Winfred G; Wang, Peng

    2016-08-01

    The seaweed Ulva prolifera, distributed in inter-tidal zones worldwide, contains a large percentage of cellulosic materials. The technical feasibility of using U. prolifera residue (UPR) obtained after extraction of polysaccharides as a renewable energy resource was investigated. An environment-friendly and economical pretreatment process was conducted using hydrogen peroxide. The hydrogen peroxide pretreatment improved the efficiency of enzymatic hydrolysis. The resulting yield of reducing sugar reached a maximum of 0.42g/g UPR under the optimal pretreatment condition (hydrogen peroxide 0.2%, 50°C, pH 4.0, 12h). The rate of conversion of reducing sugar in the concentrated hydrolysates to bioethanol reached 31.4% by Saccharomyces cerevisiae fermentation, which corresponds to 61.7% of the theoretical maximum yield. Compared with other reported traditional processes on Ulva biomass, the reducing sugar and bioethanol yield are substantially higher. Thus, hydrogen peroxide pretreatment is an effective enhancement of the process of bioethanol production from the seaweed U. prolifera. Copyright © 2016 Elsevier Ltd. All rights reserved.

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

    NASA Astrophysics Data System (ADS)

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

    2013-04-01

    Due to the fact that the resources of fossil fuels are steadily decreasing, researchers have been trying to find alternatives over the past few years. As bioethanol of the first generation is based on potential food, its production has become an increasingly controversial topic. Therefore the focus of research currently is on the production of bioethanol of the second generation, which is made from cellulosic and lignocellulosic materials. However, for the production of bioethanol of the second generation the fibres have to be pre-treated. In this work the mass balances of various agricultural residues available in Austria were generated and examined in lab scale experiments for their bioethanol potential. The residues were pretreatment by means of state of the art technology (steam explosion), enzymatically hydrolysed and fermented with yeast to produce ethanol. Special attention was paid the mass balance of the overall process. Due to the pretreatment the proportion of cellulose increases with the duration of the pre-treatment, whereby the amount of hemicellulose decreases greatly. However, the total losses were increasing with the duration of the pre-treatment, and the losses largely consist of hemicellulose. The ethanol yield varied depending on the cellulose content of the substrates. So rye straw 200 °C 20 min reaches an ethanol yield of 169 kg/t, by far the largest yield. As result on the basis of the annual straw yield in Austria, approximately 210 000 t of bioethanol (266 million litres) could be produced from the straw of wheat (Triticum vulgare), rye (Secale cereale), oat (Avena sativa) and corn (Zea mays) as well as elephant grass (Miscanthus sinensis) using appropriate pre-treatment. So the greenhouse gas emissions produced by burning fossil fuels could be reduced significantly. About 1.8 million tons of motor gasoline are consumed in Austria every year. The needed quantity for a transition to E10 biofuels could thus be easily provided by bioethanol

  18. Utilizing thermophilic microbe in lignocelluloses based bioethanol production: Review

    NASA Astrophysics Data System (ADS)

    Sriharti, Agustina, Wawan; Ratnawati, Lia; Rahman, Taufik; Salim, Takiyah

    2017-01-01

    The utilization of thermophilic microbe has attracted many parties, particularly in producing an alternative fuel like ethanol. Bioethanol is one of the alternative energy sources substituting for earth oil in the future. The advantage of using bioethanol is that it can reduce pollution levels and global warming because the result of bioethanol burning doesn't bring in a net addition of CO2 into environment. Moreover, decrease in the reserves of earth oil globally has also contributed to the notion on searching renewable energy resources such as bioethanol. Indonesia has a high biomass potential and can be used as raw material for bioethanol. The utilization of these raw materials will reduce fears of competition foodstuffs for energy production. The enzymes that play a role in degrading lignocelluloses are cellulolytic, hemicellulolytic, and lignolytic in nature. The main enzyme with an important role in bioethanol production is a complex enzyme capable of degrading lignocelluloses. The enzyme can be produced by the thermophilik microbes of the groups of bacteria and fungi such as Trichoderma viride, Clostridium thermocellum, Bacillus sp. Bioethanol production is heavily affected by raw material composition, microorganism type, and the condition of fermentation used.

  19. Bioconversion of glycerol for bioethanol production using isolated Escherichia coli ss1

    PubMed Central

    Suhaimi, Sheril Norliana; Phang, Lai-Yee; Maeda, Toshinari; Abd-Aziz, Suraini; Wakisaka, Minato; Shirai, Yoshihito; Hassan, Mohd Ali

    2012-01-01

    Bioconverting glycerol into various valuable products is one of glycerol's promising applications due to its high availability at low cost and the existence of many glycerol-utilizing microorganisms. Bioethanol and biohydrogen, which are types of renewable fuels, are two examples of bioconverted products. The objectives of this study were to evaluate ethanol production from different media by local microorganism isolates and compare the ethanol fermentation profile of the selected strains to use of glucose or glycerol as sole carbon sources. The ethanol fermentations by six isolates were evaluated after a preliminary screening process. Strain named SS1 produced the highest ethanol yield of 1.0 mol: 1.0 mol glycerol and was identified as Escherichia coli SS1 Also, this isolated strain showed a higher affinity to glycerol than glucose for bioethanol production. PMID:24031858

  20. Assessment of holocellulose for the production of bioethanol by conserving Pinus radiata cones as renewable feedstock.

    PubMed

    Victor, Amudhavalli; Pulidindi, Indra Neel; Gedanken, Aharon

    2015-10-01

    Renewable and green energy sources are much sought. Bioethanol is an environmentally friendly transportation fuel. Pine cones from Pinus radiata were shown to be a potential feedstock for the production of bioethanol. Alkaline (NaOH) pretreatment was carried out to delignify the lignocellulosic material and generate holocellulose (72 wt. % yield). The pretreated biomass was hydrolysed using HCl as catalyst under microwave irradiation and hydrothermal conditions. Microwave irradiation was found to be better than the hydrothermal process. Microwave irradiation accelerated the hydrolysis of biomass (42 wt. % conversion) with the reaction conditions being 3 M HCl and 5 min of irradiation time. Interestingly, even the xylose, which is the major component of the hydrolyzate was found to be metabolized to ethanol using Baker's yeast (Saccharomyces cerevisiae) under the experimental conditions. 5.7 g of ethanol could be produced from 100 g of raw pine cones.

  1. Development of a novel sequential pretreatment strategy for the production of bioethanol from sugarcane trash.

    PubMed

    Raghavi, Subbiah; Sindhu, Raveendran; Binod, Parameswaran; Gnansounou, Edgard; Pandey, Ashok

    2016-01-01

    A novel sequential pretreatment strategy using biodiesel industry generated waste glycerol assisted transition metal and alkali pretreatment of sugarcane trash were developed for the production of bioethanol. Various process parameters affecting pretreatment as well as hydrolysis were optimized by adopting a Taguchi design. This novel method was found to be superior when compared to conventional pretreatment strategies like acid and alkali in removing hemicelluloses and lignin and the hydrolyzate is devoid of major fermentation inhibitors like organic acids and furfurals. Physico-chemical changes of the native and the pretreated biomass were evaluated by scanning electron microscopy (SEM), X-ray diffraction (XRD) and Fourier Transform Infrared Spectroscopy (FTIR) analysis. Under optimized hydrolysis conditions 0.796 g of reducing sugar (pentoses and hexoses) per g of dry biomass after saccharification was produced. Fermentation of the non-detoxified hydrolyzate using Saccharomyces cerevisiae produced 31.928 g of bioethanol per g of dry biomass with an efficiency of 78.89%.

  2. The optimized CO2-added ammonia explosion pretreatment for bioethanol production from rice straw.

    PubMed

    Cha, Young-Lok; Yang, Jungwoo; Ahn, Jong-Woong; Moon, Youn-Ho; Yoon, Young-Mi; Yu, Gyeong-Dan; An, Gi Hong; Choi, In-Hu

    2014-09-01

    A CO2-added ammonia explosion pretreatment was performed for bioethanol production from rice straw. The pretreatment conditions, such as ammonia concentration, CO2 loading level, residence time, and temperature were optimized using response surface methodology. The response for optimization was defined as the glucose conversion rate. The optimized pretreatment conditions resulting in maximal glucose yield (93.6 %) were determined as 14.3 % of ammonia concentration, 2.2 MPa of CO2 loading level, 165.1 °C of temperature, and 69.8 min of residence time. Scanning electron microscopy analysis showed that pretreatment of rice straw strongly increased the surface area and pore size, thus increasing enzymatic accessibility for enzymatic saccharification. Finally, an ethanol yield of 97 % was achieved via simultaneous saccharification and fermentation. Thus, the present study suggests that CO2-added ammonia pretreatment is an appropriate process for bioethanol production from rice straw.

  3. Two stage bioethanol refining with multi litre stacked microbial fuel cell and microbial electrolysis cell.

    PubMed

    Sugnaux, Marc; Happe, Manuel; Cachelin, Christian Pierre; Gloriod, Olivier; Huguenin, Gérald; Blatter, Maxime; Fischer, Fabian

    2016-12-01

    Ethanol, electricity, hydrogen and methane were produced in a two stage bioethanol refinery setup based on a 10L microbial fuel cell (MFC) and a 33L microbial electrolysis cell (MEC). The MFC was a triple stack for ethanol and electricity co-generation. The stack configuration produced more ethanol with faster glucose consumption the higher the stack potential. Under electrolytic conditions ethanol productivity outperformed standard conditions and reached 96.3% of the theoretically best case. At lower external loads currents and working potentials oscillated in a self-synchronized manner over all three MFC units in the stack. In the second refining stage, fermentation waste was converted into methane, using the scale up MEC stack. The bioelectric methanisation reached 91% efficiency at room temperature with an applied voltage of 1.5V using nickel cathodes. The two stage bioethanol refining process employing bioelectrochemical reactors produces more energy vectors than is possible with today's ethanol distilleries.

  4. Thermotolerant Yeasts for Bioethanol Production Using Lignocellulosic Substrates

    NASA Astrophysics Data System (ADS)

    Pasha, Chand; Rao, L. Venkateswar

    glucose without a physical and chemical pre-treatment. The pre-treatment processes normally applied on the different substrates are acidic hydrolysis, steam explosion and wet oxidation. A problem for most pretreatment methods is the generation of compounds that are inhibitory towards the fermenting microorganisms, primarily phenols. Degradation products that could have inhibitory action in later fermentation steps are avoided during pre-treatment by wet oxidation. Followed by pre treatment, hydrolysed with enzymes known as cellulases and hemicellulases, which hydrolyse cellulose and hemicellulose respectively. The production of bioethanol requires two steps, fermentation and distillation. Practically all ethanol fermentation is still based on Saccharomyces cerevisiae . The fermentation using thermotolerant yeasts has more advantageous in that they have faster fermentation rates, avoid the cooling costs, and decrease the over all fermentation costs, so that ethanol can be made available at cheaper rates. In addition they can be used for efficient simultaneous saccharification and fermentation of cellulose by cellulases because the temperature optimum of cellulase enzymes (about 40 ° C to 45 ° C) is close to the fermentation temperature of thermotolerant yeasts. Hence selection and improvement of thermotolerant yeasts for bioconversion of lignocellulosic substrates is very useful.

  5. Evaluation of bioethanol production from carob pods by Zymomonas mobilis and Saccharomyces cerevisiae In solid submerged fermentation.

    PubMed

    Saharkhiz, Saeed; Mazaheri, Davood; Shojaosadati, Seyed Abbas

    2013-01-01

    Bioethanol production from carob pods has attracted many researchers due to its high sugar content. Both Zymomonas mobilis and Saccharomyces cerevisiae have been used previously for this purpose in submerged and solid-state fermentation. Since extraction of sugars from the carob pod particles is a costly process, solid-state and solid submerged fermentations, which do not require the sugar extraction step, may be economical processes for bioethanol production. The aim of this study is to evaluate the bioethanol production in solid submerged fermentation from carob pods. The maximum ethanol production of 0.42 g g(-1) initial sugar was obtained for Z. mobilis at 30°C, initial pH 5.3, and inoculum size of 5% v/v, 9 g carob powder per 50 mL of culture media, agitation rate 0 rpm, and fermentation time of 40 hr. The maximum ethanol production for S. cerevisiae was 0.40 g g(-1) initial sugar under the same condition. The results obtained in this research are comparable to those of Z. mobilis and S. cerevisiae performance in other culture mediums from various agricultural sources. Accordingly, solid submerged fermentation has a potential to be an economical process for bioethanol production from carob pods.

  6. Enzymatic saccharification and bioethanol production from Cynara cardunculus pretreated by steam explosion.

    PubMed

    Fernandes, Maria C; Ferro, Miguel D; Paulino, Ana F C; Mendes, Joana A S; Gravitis, Janis; Evtuguin, Dmitry V; Xavier, Ana M R B

    2015-06-01

    The correct choice of the specific lignocellulosic biomass pretreatment allows obtaining high biomass conversions for biorefinery implementations and cellulosic bioethanol production from renewable resources. Cynara cardunculus (cardoon) pretreated by steam explosion (SE) was involved in second-generation bioethanol production using separate hydrolysis and fermentation (SHF) or simultaneous saccharification and fermentation (SSF) processes. Steam explosion pretreatment led to partial solubilisation of hemicelluloses and increased the accessibility of residual polysaccharides towards enzymatic hydrolysis revealing 64% of sugars yield against 11% from untreated plant material. Alkaline extraction after SE pretreatment of cardoon (CSEOH) promoted partial removal of degraded lignin, tannins, extractives and hemicelluloses thus allowing to double glucose concentration upon saccharification step. Bioethanol fermentation in SSF mode was faster than SHF process providing the best results: ethanol concentration 18.7 g L(-1), fermentation efficiency of 66.6% and a yield of 26.6g ethanol/100 g CSEOH or 10.1 g ethanol/100 g untreated cardoon. Copyright © 2015 Elsevier Ltd. All rights reserved.

  7. Comparison of red microalgae (Porphyridium cruentum) culture conditions for bioethanol production.

    PubMed

    Kim, Ho Myeong; Oh, Chi Hoon; Bae, Hyeun-Jong

    2017-06-01

    Microalgae biomass are useful resources in biofuel production. The objective of this study was to evaluate bioethanol production in response to Porphyridium cruemtum culture conditions. Enzymatic hydrolysis of seawater P. cruemtum (SPC) and freshwater P. cruemtum (FPC, 1% substrate loading, w/v) resulted in glucose conversion yields of 89.8 and 85.3%, respectively, without any pretreatment. However, FPC hydrolysate was more efficiently converted to ethanol about 7.1% than SPC hydrolysate. The comparison of separate hydrolysis and fermentation (SHF) and simultaneous saccharification and fermentation (SSF) showed that SSF processing is a superior method for bioethanol production from both SPC and FPC. Though SSF processing (5% substrate loading, w/v) in a 500-mL twin-neck round bottom flask, we achieved ethanol conversion yields of 65.4 and 70.3% from SPC and FPC, respectively, after 9h. These findings indicate that P. cruemtum can grow in freshwater conditions and is an efficient candidate for bioethanol production. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. Kappaphycus alvarezii as a source of bioethanol.

    PubMed

    Khambhaty, Yasmin; Mody, Kalpana; Gandhi, Mahesh R; Thampy, Sreekumaran; Maiti, Pratyush; Brahmbhatt, Harshad; Eswaran, Karuppanan; Ghosh, Pushpito K

    2012-01-01

    The present study describes production of bio-ethanol from fresh red alga, Kappaphycus alvarezii. It was crushed to expel sap--a biofertilizer--while residual biomass was saccharified at 100 °C in 0.9 N H2SO4. The hydrolysate was repeatedly treated with additional granules to achieve desired reducing sugar concentration. The best yields for saccharification, inclusive of sugar loss in residue, were 26.2% and 30.6% (w/w) at laboratory (250 g) and bench (16 kg) scales, respectively. The hydrolysate was neutralized with lime and the filtrate was desalted by electrodialysis. Saccharomyces cerevisiae (NCIM 3523) was used for ethanol production from this non-traditional bio-resource. Fermentation at laboratory and bench scales converted ca. 80% of reducing sugar into ethanol in near quantitative selectivity. A petrol vehicle was successfully run with E10 gasoline made from the seaweed-based ethanol. Co-production of ethanol and bio-fertilizer from this seaweed may emerge as a promising alternative to land-based bio-ethanol.

  9. Integrated bioenergy complex for the production of power, heat and bio-ethanol

    SciTech Connect

    Taviani, M.; Chiaramonti, D.; Tondi, G.; Grassi, G.

    1998-07-01

    In this paper an integrated bioenergy complex for the production of power, heat and bio-ethanol is presented. Ethanol, in fact, has been recognized as a high-quality transportation fuel. The reduction of petroleum consumption, especially for transport, is a strategic goal especially for those countries that already have or will experience an intensive industrial development in the next future. For these motivations, the production of bio-ethanol from Sweet Sorghum (which is now one of the most promising crop for this application in term of productivity, inputs demand, and flexibility) is of great interest in most of countries. The proposed integrated complex produces power, heat and bio-ethanol: the produced power and heat are partly used for bio-ethanol processing and biomass pre-treatment, partly to be sold to the market. This system has important innovations allowing a decentralized energy and ethanol production and creating new local jobs. The small power plant is based upon a steam cycle with an advanced low emission combustor, capable of burning different biomass resources with a modest decrease in the efficiency value. The Bioenergy Complex, suitable to satisfy the needs of a 3,000 inhabitants village, is composed by the following sub-systems: (1) Sweet Sorghum plantation (250 ha); the main products are: dry bagasse (approximately 3,900 Ton/year), grains (1,300 Ton/y) and sugar (1,850 Ton/y); (2) Cane crushing--sugar juice extraction system; (3) Sugar juice fermentation and distillation ethanol production (approx. 835 Ton/y); (4) Biomass pre-treatment components (grinding, drying, briquetting, storage, etc.); and (5) Cogeneration unit--the expansion unit is constituted by a last generation reciprocating steam engine, coupled with a 500 kWe alternator; the heat of the expanded flow is removed in the condenser, with an available thermal power of approximately 2,000 kWt.

  10. Optimization of enzymatic hydrolysis and fermentation conditions for improved bioethanol production from potato peel residues.

    PubMed

    Ben Taher, Imen; Fickers, Patrick; Chniti, Sofien; Hassouna, Mnasser

    2016-12-20

    The aim of this work was the optimization of the enzyme hydrolysis of potato peel residues (PPR) for bioethanol production. The process included a pretreatment step followed by an enzyme hydrolysis using crude enzyme system composed of cellulase, amylase and hemicellulase, produced by a mixed culture of Aspergillus niger and Trichoderma reesei. Hydrothermal, alkali and acid pretreatments were considered with regards to the enhancement of enzyme hydrolysis of potato peel residues. The obtained results showed that hydrothermal pretreatment lead to a higher enzyme hydrolysis yield compared to both acid and alkali pretreatments. Enzyme hydrolysis was also optimized for parameters such as temperature, pH, substrate loading and surfactant loading using a response surface methodology. Under optimized conditions, 77 g L(-1) of reducing sugars were obtained. Yeast fermentation of the released reducing sugars led to an ethanol titer of 30 g L(-1) after supplementation of the culture medium with ammonium sulfate. Moreover, a comparative study between acid and enzyme hydrolysis of potato peel residues was investigated. Results showed that enzyme hydrolysis offers higher yield of bioethanol production than acid hydrolysis. These results highlight the potential of second generation bioethanol production from potato peel residues treated with onsite produced hydrolytic enzymes. © 2016 American Institute of Chemical Engineers Biotechnol. Prog., 2016.

  11. Production of D-tagatose and bioethanol from onion waste by an intergrating bioprocess.

    PubMed

    Kim, Ho Myeong; Song, Younho; Wi, Seung Gon; Bae, Hyeun-Jong

    2017-09-15

    The rapid increase of agricultural waste is becoming a burgeoning problem and considerable efforts are being made by numerous researchers to convert it into a high-value resource material. Onion waste is one of the biggest issues in a world of dwindling resource. In this study, the potential of onion juice residue (OJR) for producing valuable rare sugar or bioethanol was evaluated. Purified Paenibacillus polymyxaL-arabinose isomerase (PPAI) has a molecular weight of approximately 53kDa, and exhibits maximal activity at 30°C and pH 7.5 in the presence of 0.8mM Mn(2+). PPAI can produce 0.99g D-tagatose from 10g OJR. In order to present another application for OJR, we produced 1.56g bioethanol from 10g OJR through a bioconversion and fermentation process. These results indicate that PPAI can be used for producing rare sugars in an industrial setting, and OJR can be converted to D-tagatose and bioethanol. Copyright © 2017 Elsevier B.V. All rights reserved.

  12. Screening of Non- Saccharomyces cerevisiae Strains for Tolerance to Formic Acid in Bioethanol Fermentation.

    PubMed

    Oshoma, Cyprian E; Greetham, Darren; Louis, Edward J; Smart, Katherine A; Phister, Trevor G; Powell, Chris; Du, Chenyu

    2015-01-01

    Formic acid is one of the major inhibitory compounds present in hydrolysates derived from lignocellulosic materials, the presence of which can significantly hamper the efficiency of converting available sugars into bioethanol. This study investigated the potential for screening formic acid tolerance in non-Saccharomyces cerevisiae yeast strains, which could be used for the development of advanced generation bioethanol processes. Spot plate and phenotypic microarray methods were used to screen the formic acid tolerance of 7 non-Saccharomyces cerevisiae yeasts. S. kudriavzeii IFO1802 and S. arboricolus 2.3319 displayed a higher formic acid tolerance when compared to other strains in the study. Strain S. arboricolus 2.3319 was selected for further investigation due to its genetic variability among the Saccharomyces species as related to Saccharomyces cerevisiae and availability of two sibling strains: S. arboricolus 2.3317 and 2.3318 in the lab. The tolerance of S. arboricolus strains (2.3317, 2.3318 and 2.3319) to formic acid was further investigated by lab-scale fermentation analysis, and compared with S. cerevisiae NCYC2592. S. arboricolus 2.3319 demonstrated improved formic acid tolerance and a similar bioethanol synthesis capacity to S. cerevisiae NCYC2592, while S. arboricolus 2.3317 and 2.3318 exhibited an overall inferior performance. Metabolite analysis indicated that S. arboricolus strain 2.3319 accumulated comparatively high concentrations of glycerol and glycogen, which may have contributed to its ability to tolerate high levels of formic acid.

  13. Screening of Non- Saccharomyces cerevisiae Strains for Tolerance to Formic Acid in Bioethanol Fermentation

    PubMed Central

    Oshoma, Cyprian E.; Greetham, Darren; Louis, Edward J.; Smart, Katherine A.; Phister, Trevor G.; Powell, Chris; Du, Chenyu

    2015-01-01

    Formic acid is one of the major inhibitory compounds present in hydrolysates derived from lignocellulosic materials, the presence of which can significantly hamper the efficiency of converting available sugars into bioethanol. This study investigated the potential for screening formic acid tolerance in non-Saccharomyces cerevisiae yeast strains, which could be used for the development of advanced generation bioethanol processes. Spot plate and phenotypic microarray methods were used to screen the formic acid tolerance of 7 non-Saccharomyces cerevisiae yeasts. S. kudriavzeii IFO1802 and S. arboricolus 2.3319 displayed a higher formic acid tolerance when compared to other strains in the study. Strain S. arboricolus 2.3319 was selected for further investigation due to its genetic variability among the Saccharomyces species as related to Saccharomyces cerevisiae and availability of two sibling strains: S. arboricolus 2.3317 and 2.3318 in the lab. The tolerance of S. arboricolus strains (2.3317, 2.3318 and 2.3319) to formic acid was further investigated by lab-scale fermentation analysis, and compared with S. cerevisiae NCYC2592. S. arboricolus 2.3319 demonstrated improved formic acid tolerance and a similar bioethanol synthesis capacity to S. cerevisiae NCYC2592, while S. arboricolus 2.3317 and 2.3318 exhibited an overall inferior performance. Metabolite analysis indicated that S. arboricolus strain 2.3319 accumulated comparatively high concentrations of glycerol and glycogen, which may have contributed to its ability to tolerate high levels of formic acid. PMID:26284784

  14. Bioethanol production from dedicated energy crops and residues in Arkansas, USA.

    PubMed

    Ge, Xumeng; Burner, David M; Xu, Jianfeng; Phillips, Gregory C; Sivakumar, Ganapathy

    2011-01-01

    Globally, one of the major technologic goals is to achieve cost-effective lignocellulosic ethanol production from biomass feedstocks. Lignocellulosic biomass of four dedicated energy crops [giant reed (Arundo donax L.), elephantgrass (Pennisetum purpureum (Schumach), Miscanthus × giganteus (Illinois clone), and (clone Q42641) {hybrid of Miscanthus sinensis Anderss. and Miscanthus sacchariflorus (Maxim)}, Hack. called giant miscanthus, and sugarcane clone US 84-1028 (Saccharum L. spp. hybrid)] and residues from two crops [soybean (Glycine max (L.) Merr.) litter and rice (Oryza sativa L.) husk] were tested for bioethanol production using cellulose solvent-based lignocellulose fractionation (CSLF) pretreatment and enzymatic (cellulase) hydrolysis. Giant miscanthus (Illinois), giant reed, giant miscanthus (Q42641), elephantgrass, and sugarcane all yielded higher amount of glucose on a biomass dry weight basis (0.290-0.331 g/g), than did rice husk (0.181 g/g) and soybean litter (0.186 g/g). To reduce the capital investment for energy consumption in fermentation, we used a self-flocculating yeast strain (SPSC01) to ferment the lignocellulosic biomass hydrolysates. Bioethanol production was ∼0.1 g/g in dedicated energy crops and less in two crop residues. These methods and data can help to develop a cost-effective downstream process for bioethanol production.

  15. Influence of high gravity process conditions on the environmental impact of ethanol production from wheat straw.

    PubMed

    Janssen, Matty; Tillman, Anne-Marie; Cannella, David; Jørgensen, Henning

    2014-12-01

    Biofuel production processes at high gravity are currently under development. Most of these processes however use sugars or first generation feedstocks as substrate. This paper presents the results of a life cycle assessment (LCA) of the production of bio-ethanol at high gravity conditions from a second generation feedstock, namely, wheat straw. The LCA used lab results of a set of 36 process configurations in which dry matter content, enzyme preparation and loading, and process strategy were varied. The LCA results show that higher dry matter content leads to a higher environmental impact of the ethanol production, but this can be compensated by reducing the impact of enzyme production and use, and by polyethylene glycol addition at high dry matter content. The results also show that the renewable and non-renewable energy use resulting from the different process configurations ultimately determine their environmental impact. Copyright © 2014 Elsevier Ltd. All rights reserved.

  16. A novel solid state fermentation coupled with gas stripping enhancing the sweet sorghum stalk conversion performance for bioethanol

    PubMed Central

    2014-01-01

    Background Bioethanol production from biomass is becoming a hot topic internationally. Traditional static solid state fermentation (TS-SSF) for bioethanol production is similar to the traditional method of intermittent operation. The main problems of its large-scale intensive production are the low efficiency of mass and heat transfer and the high ethanol inhibition effect. In order to achieve continuous production and high conversion efficiency, gas stripping solid state fermentation (GS-SSF) for bioethanol production from sweet sorghum stalk (SSS) was systematically investigated in the present study. Results TS-SSF and GS-SSF were conducted and evaluated based on different SSS particle thicknesses under identical conditions. The ethanol yield reached 22.7 g/100 g dry SSS during GS-SSF, which was obviously higher than that during TS-SSF. The optimal initial gas stripping time, gas stripping temperature, fermentation time, and particle thickness of GS-SSF were 10 h, 35°C, 28 h, and 0.15 cm, respectively, and the corresponding ethanol stripping efficiency was 77.5%. The ethanol yield apparently increased by 30% with the particle thickness decreasing from 0.4 cm to 0.05 cm during GS-SSF. Meanwhile, the ethanol yield increased by 6% to 10% during GS-SSF compared with that during TS-SSF under the same particle thickness. The results revealed that gas stripping removed the ethanol inhibition effect and improved the mass and heat transfer efficiency, and hence strongly enhanced the solid state fermentation (SSF) performance of SSS. GS-SSF also eliminated the need for separate reactors and further simplified the bioethanol production process from SSS. As a result, a continuous conversion process of SSS and online separation of bioethanol were achieved by GS-SSF. Conclusions SSF coupled with gas stripping meet the requirements of high yield and efficient industrial bioethanol production. It should be a novel bioconversion process for bioethanol production from SSS

  17. A novel solid state fermentation coupled with gas stripping enhancing the sweet sorghum stalk conversion performance for bioethanol.

    PubMed

    Chen, Hong-Zhang; Liu, Zhi-Hua; Dai, Shu-Hua

    2014-01-01

    Bioethanol production from biomass is becoming a hot topic internationally. Traditional static solid state fermentation (TS-SSF) for bioethanol production is similar to the traditional method of intermittent operation. The main problems of its large-scale intensive production are the low efficiency of mass and heat transfer and the high ethanol inhibition effect. In order to achieve continuous production and high conversion efficiency, gas stripping solid state fermentation (GS-SSF) for bioethanol production from sweet sorghum stalk (SSS) was systematically investigated in the present study. TS-SSF and GS-SSF were conducted and evaluated based on different SSS particle thicknesses under identical conditions. The ethanol yield reached 22.7 g/100 g dry SSS during GS-SSF, which was obviously higher than that during TS-SSF. The optimal initial gas stripping time, gas stripping temperature, fermentation time, and particle thickness of GS-SSF were 10 h, 35°C, 28 h, and 0.15 cm, respectively, and the corresponding ethanol stripping efficiency was 77.5%. The ethanol yield apparently increased by 30% with the particle thickness decreasing from 0.4 cm to 0.05 cm during GS-SSF. Meanwhile, the ethanol yield increased by 6% to 10% during GS-SSF compared with that during TS-SSF under the same particle thickness. The results revealed that gas stripping removed the ethanol inhibition effect and improved the mass and heat transfer efficiency, and hence strongly enhanced the solid state fermentation (SSF) performance of SSS. GS-SSF also eliminated the need for separate reactors and further simplified the bioethanol production process from SSS. As a result, a continuous conversion process of SSS and online separation of bioethanol were achieved by GS-SSF. SSF coupled with gas stripping meet the requirements of high yield and efficient industrial bioethanol production. It should be a novel bioconversion process for bioethanol production from SSS biomass.

  18. Non-destructive analysis of the conformational differences among feedstock sources and their corresponding co-products from bioethanol production with molecular spectroscopy

    NASA Astrophysics Data System (ADS)

    Gamage, I. H.; Jonker, A.; Zhang, X.; Yu, P.

    2014-01-01

    The objective of this study was to determine the possibility of using molecular spectroscopy with multivariate technique as a fast method to detect the source effects among original feedstock sources of wheat and their corresponding co-products, wheat DDGS, from bioethanol production. Different sources of the bioethanol feedstock and their corresponding bioethanol co-products, three samples per source, were collected from the same newly-built bioethanol plant with current bioethanol processing technology. Multivariate molecular spectral analyses were carried out using agglomerative hierarchical cluster analysis (AHCA) and principal component analysis (PCA). The molecular spectral data of different feedstock sources and their corresponding co-products were compared at four different regions of ca. 1800-1725 cm-1 (carbonyl Cdbnd O ester, mainly related to lipid structure conformation), ca. 1725-1482 cm-1 (amide I and amide II region mainly related to protein structure conformation), ca. 1482-1180 cm-1 (mainly associated with structural carbohydrate) and ca. 1180-800 cm-1 (mainly related to carbohydrates) in complex plant-based system. The results showed that the molecular spectroscopy with multivariate technique could reveal the structural differences among the bioethanol feedstock sources and among their corresponding co-products. The AHCA and PCA analyses were able to distinguish the molecular structure differences associated with chemical functional groups among the different sources of the feedstock and their corresponding co-products. The molecular spectral differences indicated the differences in functional, biomolecular and biopolymer groups which were confirmed by wet chemical analysis. These biomolecular and biopolymer structural differences were associated with chemical and nutrient profiles and nutrient utilization and availability. Molecular spectral analyses had the potential to identify molecular structure difference among bioethanol feedstock sources

  19. Non-destructive analysis of the conformational differences among feedstock sources and their corresponding co-products from bioethanol production with molecular spectroscopy.

    PubMed

    Gamage, I H; Jonker, A; Zhang, X; Yu, P

    2014-01-24

    The objective of this study was to determine the possibility of using molecular spectroscopy with multivariate technique as a fast method to detect the source effects among original feedstock sources of wheat and their corresponding co-products, wheat DDGS, from bioethanol production. Different sources of the bioethanol feedstock and their corresponding bioethanol co-products, three samples per source, were collected from the same newly-built bioethanol plant with current bioethanol processing technology. Multivariate molecular spectral analyses were carried out using agglomerative hierarchical cluster analysis (AHCA) and principal component analysis (PCA). The molecular spectral data of different feedstock sources and their corresponding co-products were compared at four different regions of ca. 1800-1725 cm(-1) (carbonyl CO ester, mainly related to lipid structure conformation), ca. 1725-1482 cm(-1) (amide I and amide II region mainly related to protein structure conformation), ca. 1482-1180 cm(-1) (mainly associated with structural carbohydrate) and ca. 1180-800 cm(-1) (mainly related to carbohydrates) in complex plant-based system. The results showed that the molecular spectroscopy with multivariate technique could reveal the structural differences among the bioethanol feedstock sources and among their corresponding co-products. The AHCA and PCA analyses were able to distinguish the molecular structure differences associated with chemical functional groups among the different sources of the feedstock and their corresponding co-products. The molecular spectral differences indicated the differences in functional, biomolecular and biopolymer groups which were confirmed by wet chemical analysis. These biomolecular and biopolymer structural differences were associated with chemical and nutrient profiles and nutrient utilization and availability. Molecular spectral analyses had the potential to identify molecular structure difference among bioethanol feedstock

  20. Isolation and characterization of marine bacteria from macroalgae Gracilaria salicornia and Gelidium latifolium on agarolitic activity for bioethanol production

    NASA Astrophysics Data System (ADS)

    Kawaroe, M.; Pratiwi, I.; Sunudin, A.

    2017-05-01

    Gracilaria salicornia and Gelidium latifolium have high content of agar and potential to be use as raw material for bioethanol. In bioethanol production, one of the processes level is enzyme hydrolysis. Various microorganisms, one of which is bacteria, can carry out the enzyme hydrolysis. Bacteria that degrade the cell walls of macroalgae and produce an agarase enzyme called agarolytic bacteria. The purpose of this study was to isolate bacteria from macroalgae G. salicornia and G. latifolium, which has the highest agarase enzyme activities, and to obtain agarase enzyme characteristic for bioethanol production. There are two isolates bacteria resulted from G. salicornia that are N1 and N3 and there are two isolates from G. latifolium that are BSUC2 and BSUC4. The result of agarase enzyme qualitative test showed that isolates bacteria from G. latifolium were greater than G. salicornia. The highest agarolitic index of bacteria from G. salicornia produced by isolate N3 was 2.32 mm and isolate N3 was 2.27 mm. Bacteria from G. latifolium produced by isolate BSUC4 was 4.28 mm and isolate BSUC2 was 4.18 mm, respectively. Agarase enzyme activities from isolates N1 and N3 were optimum working at pH 7 and temperature 30 °C, while from isolates BSUC4 was optimum at pH 7 and temperature 50 °C. This is indicated that the four bacteria are appropriate to hydrolyze macro alga for bioethanol production.

  1. On-board reforming of biodiesel and bioethanol for high temperature PEM fuel cells: Comparison of autothermal reforming and steam reforming

    NASA Astrophysics Data System (ADS)

    Martin, Stefan; Wörner, Antje

    2011-03-01

    In the 21st century biofuels will play an important role as alternative fuels in the transportation sector. In this paper different reforming options (steam reforming (SR) and autothermal reforming (ATR)) for the on-board conversion of bioethanol and biodiesel into a hydrogen-rich gas suitable for high temperature PEM (HTPEM) fuel cells are investigated using the simulation tool Aspen Plus. Special emphasis is placed on thermal heat integration. Methyl-oleate (C19H36O2) is chosen as reference substance for biodiesel. Bioethanol is represented by ethanol (C2H5OH). For the steam reforming concept with heat integration a maximum fuel processing efficiency of 75.6% (76.3%) is obtained for biodiesel (bioethanol) at S/C = 3. For the autothermal reforming concept with heat integration a maximum fuel processing efficiency of 74.1% (75.1%) is obtained for biodiesel (bioethanol) at S/C = 2 and λ = 0.36 (0.35). Taking into account the better dynamic behaviour and lower system complexity of the reforming concept based on ATR, autothermal reforming in combination with a water gas shift reactor is considered as the preferred option for on-board reforming of biodiesel and bioethanol. Based on the simulation results optimum operating conditions for a novel 5 kW biofuel processor are derived.

  2. To bioethanol through genomics of microbial synergies

    SciTech Connect

    Epstein,

    2013-08-27

    The strategic goal of this project was to advance our understanding of activities and interactions of microorganisms through the advancement of microbial cultivation approaches. In this project we aimed to develop, advance, and use both culture-dependent techniques to address our main hypothesis: “uncultivable” microorganisms and their consortia represent a untapped source of novel species for efficient production of bioethanol. This project has two specific goals: 1. To develop and optimize a high throughput diffusion chamber cultivation approach to isolation of novel environmental bacteria relevant to DOE missions. 2. To use the optimized method to identify and cultivate novel microbial species and their consortia that synergistically hydrolyze various substrates and ferment the sugars to ethanol.

  3. Effective heterogeneous transition metal glycerolates catalysts for one-step biodiesel production from low grade non-refined Jatropha oil and crude aqueous bioethanol

    NASA Astrophysics Data System (ADS)

    Lau, Pak-Chung; Kwong, Tsz-Lung; Yung, Ka-Fu

    2016-03-01

    The utilization of bioethanol as the alcohol source for biodiesel production is more environmentally advantageous over methanol owing to its lower toxicity, lower flammability and its sustainable supply from renewable agricultural resources. However, as the presence of water in crude bioethanol is the critical factor limiting the biodiesel production process, the energy-intensive and costly purification of bioethanol is necessary for biodiesel application. Manganese glycerolate (MnGly) is reported the first time here as a robust heterogeneous catalyst that exhibited over 90% conversion by using aqueous ethanol containing 80 wt.% of water in the production of fatty acid ethyl ester (FAEE). The employment of 95 wt.% ethanol with respect to water could achieve 99.7% feedstock conversion in 6 hours under the optimal reaction conditions: reaction temperature (150 °C), feedstock-to-ethanol molar ratio (1:20) and catalyst loading (6 wt.%). Commercially available low grade crude bioethanol with the presence of impurities like sugars were applied which demonstrated remarkable catalytic activity in 24 hours. The high water tolerance of MnGly towards biodiesel production could eventually simplify the purification of bioethanol that consumes less energy and production cost.

  4. Effective heterogeneous transition metal glycerolates catalysts for one-step biodiesel production from low grade non-refined Jatropha oil and crude aqueous bioethanol

    PubMed Central

    Lau, Pak-Chung; Kwong, Tsz-Lung; Yung, Ka-Fu

    2016-01-01

    The utilization of bioethanol as the alcohol source for biodiesel production is more environmentally advantageous over methanol owing to its lower toxicity, lower flammability and its sustainable supply from renewable agricultural resources. However, as the presence of water in crude bioethanol is the critical factor limiting the biodiesel production process, the energy-intensive and costly purification of bioethanol is necessary for biodiesel application. Manganese glycerolate (MnGly) is reported the first time here as a robust heterogeneous catalyst that exhibited over 90% conversion by using aqueous ethanol containing 80 wt.% of water in the production of fatty acid ethyl ester (FAEE). The employment of 95 wt.% ethanol with respect to water could achieve 99.7% feedstock conversion in 6 hours under the optimal reaction conditions: reaction temperature (150 °C), feedstock-to-ethanol molar ratio (1:20) and catalyst loading (6 wt.%). Commercially available low grade crude bioethanol with the presence of impurities like sugars were applied which demonstrated remarkable catalytic activity in 24 hours. The high water tolerance of MnGly towards biodiesel production could eventually simplify the purification of bioethanol that consumes less energy and production cost. PMID:27029238

  5. Effective heterogeneous transition metal glycerolates catalysts for one-step biodiesel production from low grade non-refined Jatropha oil and crude aqueous bioethanol.

    PubMed

    Lau, Pak-Chung; Kwong, Tsz-Lung; Yung, Ka-Fu

    2016-03-31

    The utilization of bioethanol as the alcohol source for biodiesel production is more environmentally advantageous over methanol owing to its lower toxicity, lower flammability and its sustainable supply from renewable agricultural resources. However, as the presence of water in crude bioethanol is the critical factor limiting the biodiesel production process, the energy-intensive and costly purification of bioethanol is necessary for biodiesel application. Manganese glycerolate (MnGly) is reported the first time here as a robust heterogeneous catalyst that exhibited over 90% conversion by using aqueous ethanol containing 80 wt.% of water in the production of fatty acid ethyl ester (FAEE). The employment of 95 wt.% ethanol with respect to water could achieve 99.7% feedstock conversion in 6 hours under the optimal reaction conditions: reaction temperature (150 °C), feedstock-to-ethanol molar ratio (1:20) and catalyst loading (6 wt.%). Commercially available low grade crude bioethanol with the presence of impurities like sugars were applied which demonstrated remarkable catalytic activity in 24 hours. The high water tolerance of MnGly towards biodiesel production could eventually simplify the purification of bioethanol that consumes less energy and production cost.

  6. [Progress and strategies on bioethanol production from lignocellulose by consolidated bioprocessing (CBP) using Saccharomyces cerevisiae].

    PubMed

    Xu, Lili; Shen, Yu; Bao, Xiaoming

    2010-07-01

    Ethanol production from lignocelluloses of consolidated bioprocessing (CBP) is a system in which cellulase and hemicellulase production, substrate hydrolysis, and fermentation are combined or partially combined by ethanologen microorganisms that express cellulolytic or hemicellulolytic enzymes or engineering cellulolytic microorganisms with ethanol production properties. Due to its potential for significant cost reduction, CBP is receiving more and more attention. In this review article, we discuss the factors that influence the expression level of cellulases in Saccharomyces cerevisiae and updated progress in bioethanol production from lignocellulose by the CBP strategy using the yeast species.

  7. Efficient approach for bioethanol production from red seaweed Gelidium amansii.

    PubMed

    Kim, Ho Myeong; Wi, Seung Gon; Jung, Sera; Song, Younho; Bae, Hyeun-Jong

    2015-01-01

    Gelidium amansii (GA), a red seaweed species, is a popular source of food and chemicals due to its high galactose and glucose content. In this study, we investigated the potential of bioethanol production from autoclave-treated GA (ATGA). The proposed method involved autoclaving GA for 60min for hydrolysis to glucose. Separate hydrolysis and fermentation processing (SHF) achieved a maximum ethanol concentration of 3.33mg/mL, with a conversion yield of 74.7% after 6h (2% substrate loading, w/v). In contrast, simultaneous saccharification and fermentation (SSF) produced an ethanol concentration of 3.78mg/mL, with an ethanol conversion yield of 84.9% after 12h. We also recorded an ethanol concentration of 25.7mg/mL from SSF processing of 15% (w/v) dry matter from ATGA after 24h. These results indicate that autoclaving can improve the glucose and ethanol conversion yield of GA, and that SSF is superior to SHF for ethanol production.

  8. Using Populus as a lignocellulosic feedstock for bioethanol.

    PubMed

    Porth, Ilga; El-Kassaby, Yousry A

    2015-04-01

    Populus species along with species from the sister genus Salix will provide valuable feedstock resources for advanced second-generation biofuels. Their inherent fast growth characteristics can particularly be exploited for short rotation management, a time and energy saving cultivation alternative for lignocellulosic feedstock supply. Salicaceae possess inherent cell wall characteristics with favorable cellulose to lignin ratios for utilization as bioethanol crop. We review economically important traits relevant for intensively managed biofuel crop plantations, genomic and phenotypic resources available for Populus, breeding strategies for forest trees dedicated to bioenergy provision, and bioprocesses and downstream applications related to opportunities using Salicaceae as a renewable resource. Challenges need to be resolved for every single step of the conversion process chain, i.e., starting from tree domestication for improved performance as a bioenergy crop, bioconversion process, policy development for land use changes associated with advanced biofuels, and harvest and supply logistics associated with industrial-scale biorefinery plants using Populus as feedstock. Significant hurdles towards cost and energy efficiency, environmental friendliness, and yield maximization with regards to biomass pretreatment, saccharification, and fermentation of celluloses and the sustainability of biorefineries as a whole still need to be overcome.

  9. Biotechnological Strategies to Improve Plant Biomass Quality for Bioethanol Production

    PubMed Central

    del Moral, Sandra; Núñez-López, Lizeth; Barrera-Figueroa, Blanca E.; Amaya-Delgado, Lorena

    2017-01-01

    The transition from an economy dependent on nonrenewable energy sources to one with higher diversity of renewables will not be a simple process. It requires an important research effort to adapt to the dynamics of the changing energy market, sort costly processes, and avoid overlapping with social interest markets such as food and livestock production. In this review, we analyze the desirable traits of raw plant materials for the bioethanol industry and the molecular biotechnology strategies employed to improve them, in either plants already under use (as maize) or proposed species (large grass families). The fundamentals of these applications can be found in the mechanisms by which plants have evolved different pathways to manage carbon resources for reproduction or survival in unexpected conditions. Here, we review the means by which this information can be used to manipulate these mechanisms for commercial uses, including saccharification improvement of starch and cellulose, decrease in cell wall recalcitrance through lignin modification, and increase in plant biomass. PMID:28951875

  10. Direct conversion of bio-ethanol to isobutene on nanosized Zn(x)Zr(y)O(z) mixed oxides with balanced acid-base sites.

    PubMed

    Sun, Junming; Zhu, Kake; Gao, Feng; Wang, Chongmin; Liu, Jun; Peden, Charles H F; Wang, Yong

    2011-07-27

    We report the design and synthesis of nanosized Zn(x)Zr(y)O(z) mixed oxides for direct and high-yield conversion of bio-ethanol to isobutene (~83%). ZnO is addded to ZrO(2) to selectively passivate zirconia's strong Lewis acidic sites and weaken Brönsted acidic sites, while simultaneously introducing basicity. As a result, the undesired reactions of bio-ethanol dehydration and acetone polymerization/coking are suppressed. Instead, a surface basic site-catalyzed ethanol dehydrogenation to acetaldehyde, acetaldehyde to acetone conversion via a complex pathway including aldol-condensation/dehydrogenation, and a Brönsted acidic site-catalyzed acetone-to-isobutene reaction pathway dominates on the nanosized Zn(x)Zr(y)O(z) mixed oxide catalyst, leading to a highly selective process for direct conversion of bio-ethanol to isobutene.

  11. Influence of processing on trichothecene levels.

    PubMed

    Hazel, Clare M; Patel, Sue

    2004-10-10

    Trichothecene mycotoxins frequently occur in cereal grains that are intended for food production. The process of converting grains into food and drinks for consumers has significant effects on the levels of toxins in the final food. Surveillance of retail food and drinks of cereal origin demonstrates that trichothecenes do survive the production processes employed. Trichothecenes are relatively heat stable chemicals, with high water solubility, properties that affect their processing fate. It is known that the extent of transmission into final food products is dependent on the pattern of Fusarium infection in the grains. For dry-milled products, the most highly contaminated fractions are those that contain the whole or the outer portions of the grain. For wet milling, the trichothecenes primarily transfer to the aqueous fractions, the most contaminated streams enter the animal food chain, although there is no evidence of significant trichothecenes transmission into animal products. However, anomalies remain in the understanding of the processing effects of several major cereal processes used in European food production (e.g. baking and brewing).

  12. Influence of weather-climatic conditions on biospheric processes

    NASA Astrophysics Data System (ADS)

    Govorushko, S. M.

    2012-12-01

    The significance of meteorological processes and phenomena in the biosphere functioning is revealed. The influence of various weather conditions on human health is considered; the factors and mechanisms of their action are described. The impact of meteorological processes on animals is discussed and concrete examples of such impacts are presented. The influence of meteorological processes and phenomena on plants at different stages of their life (pollination, growth, ripening, transport of seeds, damage, and death) and on some abiotic natural components is shown. It is inferred that weather-climatic conditions have a great influence on biospheric processes.

  13. Water embodied in bioethanol in the United States.

    PubMed

    Chiu, Yi-Wen; Walseth, Brian; Suh, Sangwon

    2009-04-15

    Prior studies have estimated that a liter of bioethanol requires 263-784 L of water from corn farm to fuel pump, but these estimates have failed to account for the widely varied regional irrigation practices. By using regional time-series agricultural and ethanol production data in the U.S., this paper estimates the state-level field-to-pump water requirement of bioethanol across the nation. The results indicate that bioethanol's water requirements can range from 5 to 2138 L per liter of ethanol depending on regional irrigation practices. The results also show that as the ethanol industry expands to areas that apply more irrigated water than others, consumptive water appropriation by bioethanol in the U.S. has increased 246% from 1.9 to 6.1 trillion liters between 2005 and 2008, whereas U.S. bioethanol production has increased only 133% from 15 to 34 billion liters during the same period. The results highlight the need to take regional specifics into account when implementing biofuel mandates.

  14. Oxidation of bioethanol using zeolite-encapsulated gold nanoparticles.

    PubMed

    Mielby, Jerrik; Abildstrøm, Jacob Oskar; Wang, Feng; Kasama, Takeshi; Weidenthaler, Claudia; Kegnaes, Søren

    2014-11-10

    With the ongoing developments in biomass conversion, the oxidation of bioethanol to acetaldehyde may become a favorable and green alternative to the preparation from ethylene. Here, a simple and effective method to encapsulate gold nanoparticles in zeolite silicalite-1 is reported and their high activity and selectivity for the catalytic gas-phase oxidation of ethanol are demonstrated. The zeolites are modified by a recrystallization process, which creates intraparticle voids and mesopores that facilitate the formation of small and disperse nanoparticles upon simple impregnation. The individual zeolite crystals comprise a broad range of mesopores and contain up to several hundred gold nanoparticles with a diameter of 2-3 nm that are distributed inside the zeolites rather than on the outer surface. The encapsulated nanoparticles have good stability and result in 50 % conversion of ethanol with 98 % selectivity toward acetaldehyde at 200 °C, which (under the given reaction conditions) corresponds to 606 mol acetaldehyde/mol Au hour(-1) .

  15. [Pretreatment of ramie and kenaf stalk for bioethanol production].

    PubMed

    Guo, Fenfen; Sun, Wan; Li, Xuezhi; Zhao, Jian; Qu, Yinbo

    2014-05-01

    Ramie and kenaf were traditional fiber crops in China, but their stalk after decorticating has not been used effectively. The stalk contains a lot of cellulose, and can therefore be used for the production of bioethanol. We studied the effects of different chemical pretreatment on enzymatic digestibility of ramie stalk and kenaf stalk. Ramie and kenaf stalks pretreated with alkali were chosen to produce ethanol using quasi-simultaneous saccharification and fermentation (Q-SSF) process. The results show that for the stalks pretreated with 4% NaOH and 0.02% anthraquinone-2-sulfonic acid sodium salt (AQSS) as catalyzer at 170 degrees C for 1 h, the ethanol concentration could reach 51 g/L after fermentation for 168 h at 18% of solid substrate concentration. By fed-batch to 20% of solid substrate concentration, the ethanol concentration could reach 63 g/L, 77% and 79% of the cellulose conversion could get for ramie stalk and kenaf stalk, respectively. For kenaf stalk pretreated with 5.2% NaHSO3 and 0.2% H2SO4 at 170 degrees C for 1 h, the ethanol concentration and cellulose conversion could reach to 65 g/L and 72%, respectively.

  16. Current progress in high cell density yeast bioprocesses for bioethanol production.

    PubMed

    Westman, Johan O; Franzén, Carl Johan

    2015-08-01

    High capital costs and low reaction rates are major challenges for establishment of fermentation-based production systems in the bioeconomy. Using high cell density cultures is an efficient way to increase the volumetric productivity of fermentation processes, thereby enabling faster and more robust processes and use of smaller reactors. In this review, we summarize recent progress in the application of high cell density yeast bioprocesses for first and second generation bioethanol production. High biomass concentrations obtained by retention of yeast cells in the reactor enables easier cell reuse, simplified product recovery and higher dilution rates in continuous processes. High local cell density cultures, in the form of encapsulated or strongly flocculating yeast, furthermore obtain increased tolerance to convertible fermentation inhibitors and utilize glucose and other sugars simultaneously, thereby overcoming two additional hurdles for second generation bioethanol production. These effects are caused by local concentration gradients due to diffusion limitations and conversion of inhibitors and sugars by the cells, which lead to low local concentrations of inhibitors and glucose. Quorum sensing may also contribute to the increased stress tolerance. Recent developments indicate that high cell density methodology, with emphasis on high local cell density, offers significant advantages for sustainable second generation bioethanol production. © 2015 The Authors. Biotechnology Journal published by Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim. This is an open access article under the terms of the Creative Commons Attribution Non-Commercial Licence, which permits use, distribution and reproduction in any medium, provided the Contribution is properly cited and is not used for commercial purpose.

  17. Effects of reflux ratio and feed conditions for the purification of bioethanol in a continuous distillation column

    NASA Astrophysics Data System (ADS)

    Dasan, Y. K.; Abdullah, M. A.; Bhat, A. H.

    2014-10-01

    Continuous distillation column was used for the purification of bioethanol from fermentation of molasses using Saccharomyces cerevisia. Bioethanol produced was at 8.32% (v/v) level. The efficiency of continuous distillation process was evaluated based on reflux ratio, and feed condition. The lab results were validated using COFE simulation Software. The analyses showed that both reflux ratio and feed condition had significant effects on the distillation process. Stages increased from 1.79 to 2.26 as the reflux ratio was decreased from 90% to 45% and the saturated feed produced lower mole fraction of desired product. We concluded that the lower reflux ratio with cold feed condition was suitable for higher mole fraction of top product.

  18. Processes influencing cooling of reactor effluents

    SciTech Connect

    Magoulas, V.E.; Murphy, C.E. Jr.

    1982-06-07

    Discharge of heated reactor cooling water from SRP reactors to the Savannah River is through sections of stream channels into the Savannah River Swamp and from the swamp into the river. Significant cooling of the reactor effluents takes place in both the streams and swamp. The majority of the cooling is through processes taking place at the surface of the water. The major means of heat dissipation are convective transfer of heat to the air, latent heat transfer through evaporation and radiative transfer of infrared radiation. A model was developed which incorporates the effects of these processes on stream and swamp cooling of reactor effluents. The model was used to simulate the effect of modifications in the stream environment on the temperature of water flowing into the river. Environmental effects simulated were the effect of changing radiant heat load, the effect of changes in tree canopy density in the swamp, the effect of total removal of trees from the swamp, and the effect of diverting the heated water from L reactor from Steel Creek to Pen Branch. 6 references, 7 figures.

  19. Conversion of Wastes to Bioelectricity, Bioethanol, and Fertilizer.

    PubMed

    Khan, Abdul Majeed; Hussain, Muhammad Shoukat

    2017-08-01

      This research article presents production of bioelectricity, bioethanol, and fertilizer from different industrial wastewaters supplemented with waste fruit and vegetables. Bioelectricity was generated from wastewater through the development of different microbial fuel cells (MFCs). It was observed that the voltage was increased in series combination, whereas current was increased in parallel combinations. The series combination of four units of single-chamber and eight units of double-chamber MFCs produced the power output of 5.43 mW and 4.08 mW, respectively, which is sufficient to light up the light emitting diode (LED). Power output was increased by the addition of waste fruit and vegetables. The leftover filtrates of MFCs were used for the production of bioethanol using Saccharomyces cerevisiae, while residues were used as fertilizer to check the growth of okra plant. The result showed that minor amount of bioethanol is produced from different samples, which was confirmed by the preparation of ethylbenzoate derivative.

  20. Primary certification of reference material for electrolytic conductivity of bioethanol

    NASA Astrophysics Data System (ADS)

    da Silva, L. F.; Gomes, M. R. F.; Cassini, G. C.; Faria, A. C. V.; Fraga, I. C. S.

    2016-07-01

    Nowadays the preservation of the planet is spreading into the international scene with the use of renewable energy sources such as bioethanol. The challenge is to guarantee the quality of produced bioethanol, and the electrolytic conductivity (EC) is one of the specified parameters for this purpose. However, is necessary to demonstrate the metrological traceability of the measurement results for EC in this matrix. This study presents the certification of a reference material for EC in bioethanol by using only primary measurements. The value of primary certified reference material (CRM) is (0.77 ± 0.06) µS.cm-1, and its use will provide the metrological traceability needed for measurement results in laboratories.

  1. Bioethanol production from Gracilaria verrucosa, a red alga, in a biorefinery approach.

    PubMed

    Kumar, Savindra; Gupta, Rishi; Kumar, Gaurav; Sahoo, Dinabandhu; Kuhad, Ramesh Chander

    2013-05-01

    In this study, Gracilaria verrucosa, red seaweed has been used for production of agar and bioethanol. The algae harvested at various time durations resulted in extraction of ~27-33% agar. The leftover pulp was found to contain ~62-68% holocellulose, which on enzymatic hydrolysis yielded 0.87 g sugars/g cellulose. The enzymatic hydrolysate on fermentation with Saccharomyces cerevisiae produced ethanol with an ethanol yield of 0.43 g/g sugars. The mass balance evaluation of the complete process demonstrates that developing biorefinery approach for exploiting Gracilaria verrucosa, a red alga, could be commercially viable.

  2. Earthing the human organism influences bioelectrical processes.

    PubMed

    Sokal, Karol; Sokal, Pawel

    2012-03-01

    This article describes interaction of the Earth's mass-electrolytic conductor on the electrical environment of human organism-aqueous environment and skeleton. In this environment, bioelectrical and bioenergetical processes take place. Measurements of electric potential on tongue, teeth, nails, and in venous blood in subjects earthed and unearthed were conducted in Faraday's cage with the use of an electrometer placed outside the cage. Measurements were performed in subjects in lying position and in movements of standing up and lying down. In the unearthed human organism in the lying position, electric potential measured in examined points is around 0  mV. Contact of the Earth by a copper conductor with a moistened surface of the human body evokes a rapid decrease of electrostatic potential on the body and in venous blood to the value of approximately -200  mV. This effect is immediate and general. Interruption of contact with the Earth causes a rapid return of the potential to its initial values in examined points. Changes in electric potential measured in venous blood and on mucosal membrane of the tongue reflect alterations in electric potential of the aqueous, electrical environment. Up-and-down movement of the insulated human organism causes transient changes in potential in the human electrical environment. During the same movement, values of potential in the electrical environment of an earthed human body remain constant. These results indicate that up-and-down movement and the elimination of potentials in the electrical environment of the human organism by the Earth's mass may play a fundamental role in regulation of bioelectrical and bioenergetical processes. The Earth's electromagnetohydrodynamic potential is responsible for this phenomenon.

  3. Influence of process water quality on hydrothermal carbonization of cellulose.

    PubMed

    Lu, Xiaowei; Flora, Joseph R V; Berge, Nicole D

    2014-02-01

    Hydrothermal carbonization (HTC) is a thermal conversion process that has been shown to be environmentally and energetically advantageous for the conversion of wet feedstocks. Supplemental moisture, usually in the form of pure water, is added during carbonization to achieve feedstock submersion. To improve process sustainability, it is important to consider alternative supplemental moisture sources. Liquid waste streams may be ideal alternative liquid source candidates. Experiments were conducted to systematically evaluate how changes in pH, ionic strength, and organic carbon content of the initial process water influences cellulose carbonization. Results from the experiments conducted evaluating the influence of process water quality on carbonization indicate that changes in initial water quality do influence time-dependent carbonization product composition and yields. These results also suggest that using municipal and industrial wastewaters, with the exception of streams with high CaCl2 concentrations, may impart little influence on final carbonization products/yields.

  4. Efficient production of bioethanol from corn stover by pretreatment with a combination of sulfuric acid and sodium hydroxide.

    PubMed

    Tan, Li; Tang, Yue-Qin; Nishimura, Hiroto; Takei, Shouta; Morimura, Shigeru; Kida, Kenji

    2013-01-01

    Corn stover is the most abundant agricultural residue in China and a valuable reservoir for bioethanol production. In this study, we proposed a process for producing bioethanol from corn stover; the pretreatment prior to presaccharification, followed by simultaneous saccharification and fermentation (SSF) by using a flocculating Saccharomyces cerevisiae strain, was optimized. Pretreatment with acid-alkali combination (1% H2SO4, 150 °C, 10 min, followed by 1% NaOH, 80°C, 60 min) resulted in efficient lignin removal and excellent recovery of xylose and glucose. A glucose recovery efficiency of 92.3% was obtained by enzymatic saccharification, when the pretreated solid load was 15%. SSF was carried out at 35 °C for 36 hr after presaccharification at 50 °C for 24 hr, and an ethanol yield of 88.2% was achieved at a solid load of 15% and an enzyme dosage of 15 FPU/g pretreated corn stover.

  5. A strategy to prevent the occurrence of Lactobacillus strains using lactate-tolerant yeast Candida glabrata in bioethanol production.

    PubMed

    Watanabe, Itsuki; Nakamura, Toshihide; Shima, Jun

    2008-10-01

    Contamination of Lactobacillus sp. in the fermentation broth of bioethanol production decreases ethanol production efficiency. Although the addition of lactate to the broth can effectively inhibit the growth of Lactobacillus sp., it also greatly reduces the fermentation ability of Saccharomyces cerevisiae. To overcome this conflict, lactate-tolerant yeast strains were screened. Candida glabrata strain NFRI 3164 was found to exhibit both higher levels of lactate tolerance and fermentation ability. Co-cultivation of C. glabrata was performed with Lactobacillus brevis and Lb. fermentum, which were reported as major contaminating bacteria during bioethanol production, in culture medium containing 2% lactate. Under these culture conditions, the growth of Lactobacillus strains was greatly inhibited, but the ethanol production of C. glabrata was not significantly affected. Our data show the possibility of designing an effective fuel ethanol production process that eliminates contamination by Lactobacillus strains through the combined use of lactate addition and C. glabrata.

  6. Second-generation bio-ethanol (SGB) from Malaysian palm empty fruit bunch: energy and exergy analyses.

    PubMed

    Tan, Hui Teng; Lee, Keat Teong; Mohamed, Abdul Rahman

    2010-07-01

    Recently, second-generation bio-ethanol (SGB), which utilizes readily available lignocellulosic biomass has received much interest as another potential source of liquid biofuel comparable to biodiesel. Thus the aim of this paper is to determine the exergy efficiency and to compare the effectiveness of SGB and palm methyl ester (PME) processes. It was found that the production of bio-ethanol is more thermodynamically sustainable than that of biodiesel as the net exergy value (NExV) of SGB is 10% higher than that of PME. Contrarily, the former has a net energy value (NEV) which is 9% lower than the latter. Despite this, SGB is still strongly recommended as a potential biofuel because SGB production can help mitigate several detrimental impacts on the environment.

  7. Varieties of sweet sorghum Super-1 and Super-2 and its equipment for bioethanol in Indonesia

    NASA Astrophysics Data System (ADS)

    Pabendon, M. B.; Efendi, R.; Santoso, S. B.; Prastowo, B.

    2017-05-01

    The demands for alternative sources of energy are currently growing because people now are more aware of the many negative impacts fossil fuel gives to the environment. Plant based renewable energy provides potential sources of energy with advantages of cleaner fuel effect and capability of integration with food crop production. Sorghum have been considered to be a highly potential source of food, feed and fuel, especially sweet stalk sorghum that posses both functions as source of food from its grain and fuel made from its stalk juice. Sorghum varieties are well known to have excellent adaptability in marginal areas, especially drought prone areas where other food crops are unable to thrive. The current paper aimed to share ongoing research on many functional uses of sweet stalk sorghum varieties released at Indonesian Cereals Research Institute (ICERI). Among many varieties that had been released were two sweet stalk sorghum varieties SUPER-1 and SUPER-2 released in 2013 that stands out in biomass yield and bioethanol production. Based on various researches conducted at different location and planting season, yield potential of biomass ranged at 30 - 40 t/ha with higher yield occurred during dry season. Stalk juice sugar content in brix were found to be higher in dry season ranged at 13.6 % to 18.4 %, and the amount of juice stalk was obtained at about 30-50 % from total biomass yield. Furthermore, bioethanol production from stalk juice after fermentation was at the range of 8 to 10 % from total stalk juice volume. Modification of processing equipment of bioethanol have also been carried out and was able to increased the concentration of ethanol being distilled from 85% -92% to 90% -95%. Another result obtained was able to decreased fermentation time from 14-21 days to 6-10 days. Furthermore, the yield of ethanol from juice was also from an average of 4.95% to 6.75%.

  8. Demonstration test results of organic materials' volumetric reduction using bio-ethanol, thermal decomposition and burning

    SciTech Connect

    Tagawa, Akihiro; Watanabe, Masahisa

    2013-07-01

    To discover technologies that can be utilized for decontamination work and verify their effects, economic feasibility, safety, and other factors, the Ministry of the Environment launched the 'FY2011 Decontamination Technology Demonstrations Project' to publicly solicit decontamination technologies that would be verified in demonstration tests and adopted 22 candidates. JAEA was commissioned by the Ministry of the Environment to provide technical assistance related to these demonstrations. This paper describes the volume reduction due to bio-ethanol, thermal decomposition and burning of organic materials in this report. The purpose of this study is that to evaluate a technique that can be used as biomass energy source, while performing volume reduction of contamination organic matter generated by decontamination. An important point of volume reduction technology of contaminated organic matter, is to evaluate the mass balance in the system. Then, confirming the mass balance of radioactive material and where to stay is important. The things that are common to all technologies, are ensuring that the radioactive cesium is not released as exhaust gas, etc.. In addition, it evaluates the cost balance and energy balance in order to understand the applicability to the decontamination of volume reduction technology. The radioactive cesium remains in the carbides when organic materials are carbonized, and radioactive cesium does not transfer to bio-ethanol when organic materials are processed for bio-ethanol production. While plant operating costs are greater if radioactive materials need to be treated, if income is expected by business such as power generation, depreciation may be calculated over approximately 15 years. (authors)

  9. Production of bioethanol from pre-treated cotton fabrics and waste cotton materials.

    PubMed

    Nikolić, Svetlana; Lazić, Vesna; Veljović, Đorđe; Mojović, Ljiljana

    2017-05-15

    This study highlights the potential of cotton fabric as a promising feedstock for the production of bioethanol as renewable biofuel. The effect of corona pre-treatment of non-mercerized and mercerized cotton fabrics on glucose and ethanol yield is discussed. Fermentation kinetics for ethanol production and the basic process parameters were assessed and compared. Corona pre-treatment of cotton fabrics led to an increase in the glucose yield (compared to control sample) during enzymatic hydrolysis, and consequently the ethanol yield during fermentation by yeast Saccharomyces cerevisiae var. ellipsoideus. The system with mercerized cotton fabric was found to be superior obtaining an ethanol productivity of 0.900g/Lh and ethanol yield of 0.94g/g (based on glucose) after 6h of fermentation time. The similar results were obtained during processing of waste cotton materials performed under the same process conditions. The obtained results showed that cotton fabric could become an alternative feedstock for the bioethanol production. For potential industrial implementation the waste mercerized cotton scraps would be the materials of choice.

  10. Microbial interactions during sugar cane must fermentation for bioethanol production: does quorum sensing play a role?

    PubMed

    Brexó, Ramon Peres; Sant'Ana, Anderson de Souza

    2017-06-02

    Microbial interactions represent important modulatory role in the dynamics of biological processes. During bioethanol production from sugar cane must, the presence of lactic acid bacteria (LAB) and wild yeasts is inevitable as they originate from the raw material and industrial environment. Increasing the concentration of ethanol, organic acids, and other extracellular metabolites in the fermentation must are revealed as wise strategies for survival by certain microorganisms. Despite this, the co-existence of LAB and yeasts in the fermentation vat and production of compounds such as organic acids and other extracellular metabolites result in reduction in the final yield of the bioethanol production process. In addition to the competition for nutrients, reduction of cellular viability of yeast strain responsible for fermentation, flocculation, biofilm formation, and changes in cell morphology are listed as important factors for reductions in productivity. Although these consequences are scientifically well established, there is still a gap about the physiological and molecular mechanisms governing these interactions. This review aims to discuss the potential occurrence of quorum sensing mechanisms between bacteria (mainly LAB) and yeasts and to highlight how the understanding of such mechanisms can result in very relevant and useful tools to benefit the biofuels industry and other sectors of biotechnology in which bacteria and yeast may co-exist in fermentation processes.

  11. One-pot bioethanol production from cellulose by co-culture of Acremonium cellulolyticus and Saccharomyces cerevisiae.

    PubMed

    Park, Enoch Y; Naruse, Kazuya; Kato, Tatsuya

    2012-08-31

    While the ethanol production from biomass by consolidated bioprocess (CBP) is considered to be the most ideal process, simultaneous saccharification and fermentation (SSF) is the most appropriate strategy in practice. In this study, one-pot bioethanol production, including cellulase production, saccharification of cellulose, and ethanol production, was investigated for the conversion of biomass to biofuel by co-culture of two different microorganisms such as a hyper cellulase producer, Acremonium cellulolyticus C-1 and an ethanol producer Saccharomyces cerevisiae. Furthermore, the operational conditions of the one-pot process were evaluated for maximizing ethanol concentration from cellulose in a single reactor. Ethanol production from cellulose was carried out in one-pot bioethanol production process. A. cellulolyticus C-1 and S. cerevisiae were co-cultured in a single reactor. Cellulase producing-medium supplemented with 2.5 g/l of yeast extract was used for productions of both cellulase and ethanol. Cellulase production was achieved by A. cellulolyticus C-1 using Solka-Floc (SF) as a cellulase-inducing substrate. Subsequently, ethanol was produced with addition of both 10%(v/v) of S. cerevisiae inoculum and SF at the culture time of 60 h. Dissolved oxygen levels were adjusted at higher than 20% during cellulase producing phase and at lower than 10% during ethanol producing phase. Cellulase activity remained 8-12 FPU/ml throughout the one-pot process. When 50-300 g SF/l was used in 500 ml Erlenmeyer flask scale, the ethanol concentration and yield based on initial SF were as 8.7-46.3 g/l and 0.15-0.18 (g ethanol/g SF), respectively. In 3-l fermentor with 50-300 g SF/l, the ethanol concentration and yield were 9.5-35.1 g/l with their yields of 0.12-0.19 (g/g) respectively, demonstrating that the one-pot bioethanol production is a reproducible process in a scale-up bioconversion of cellulose to ethanol. A. cellulolyticus cells produce cellulase using SF

  12. One-pot bioethanol production from cellulose by co-culture of Acremonium cellulolyticus and Saccharomyces cerevisiae

    PubMed Central

    2012-01-01

    Background While the ethanol production from biomass by consolidated bioprocess (CBP) is considered to be the most ideal process, simultaneous saccharification and fermentation (SSF) is the most appropriate strategy in practice. In this study, one-pot bioethanol production, including cellulase production, saccharification of cellulose, and ethanol production, was investigated for the conversion of biomass to biofuel by co-culture of two different microorganisms such as a hyper cellulase producer, Acremonium cellulolyticus C-1 and an ethanol producer Saccharomyces cerevisiae. Furthermore, the operational conditions of the one-pot process were evaluated for maximizing ethanol concentration from cellulose in a single reactor. Results Ethanol production from cellulose was carried out in one-pot bioethanol production process. A. cellulolyticus C-1 and S. cerevisiae were co-cultured in a single reactor. Cellulase producing-medium supplemented with 2.5 g/l of yeast extract was used for productions of both cellulase and ethanol. Cellulase production was achieved by A. cellulolyticus C-1 using Solka-Floc (SF) as a cellulase-inducing substrate. Subsequently, ethanol was produced with addition of both 10%(v/v) of S. cerevisiae inoculum and SF at the culture time of 60 h. Dissolved oxygen levels were adjusted at higher than 20% during cellulase producing phase and at lower than 10% during ethanol producing phase. Cellulase activity remained 8–12 FPU/ml throughout the one-pot process. When 50–300 g SF/l was used in 500 ml Erlenmeyer flask scale, the ethanol concentration and yield based on initial SF were as 8.7–46.3 g/l and 0.15–0.18 (g ethanol/g SF), respectively. In 3-l fermentor with 50–300 g SF/l, the ethanol concentration and yield were 9.5–35.1 g/l with their yields of 0.12–0.19 (g/g) respectively, demonstrating that the one-pot bioethanol production is a reproducible process in a scale-up bioconversion of cellulose to ethanol. Conclusion A. cellulolyticus

  13. A co-beneficial system using aquatic plants: bioethanol production from free-floating aquatic plants used for water purification.

    PubMed

    Soda, S; Mishima, D; Inoue, D; Ike, M

    2013-01-01

    A co-beneficial system using constructed wetlands (CWs) planted with aquatic plants is proposed for bioethanol production and nutrient removal from wastewater. The potential for bioethanol production from aquatic plant biomass was experimentally evaluated. Water hyacinth and water lettuce were selected because of their high growth rates and easy harvestability attributable to their free-floating vegetation form. The alkaline/oxidative pretreatment was selected for improving enzymatic hydrolysis of the aquatic plants. Ethanol was produced with yields of 0.14-0.17 g-ethanol/ g-biomass in a simultaneous saccharification and fermentation mode using a recombinant Escherichia coli strain or a typical yeast strain Saccharomyces cerevisiae. Subsequently, the combined benefits of the CWs planted with the aquatic plants for bioethanol production and nutrient removal were theoretically estimated. For treating domestic wastewater at 1,100 m(3)/d, it was inferred that the anoxic-oxic activated sludge process consumes energy at 3,200 MJ/d, whereas the conventional activated sludge process followed by the CW consumes only 1,800 MJ/d with ethanol production at 115 MJ/d.

  14. Hierarchical economic potential approach for techno-economic evaluation of bioethanol production from palm empty fruit bunches.

    PubMed

    Do, Truong Xuan; Lim, Young-Il; Jang, Sungsoo; Chung, Hwa-Jee

    2015-01-01

    A hierarchical four-level approach to determine economic potential (4-level EP) is proposed for preliminary techno-economic analysis of new processes. The 4-level EP includes input/output structure, process flow structure, heat integration (HI), and economic feasibility. Two case studies on a 30.2 t/d (or 12.7 million l/yr) bioethanol plant with and without jet fuel production from palm empty fruit bunches (EFB) were investigated by applying the 4-level EP. The plant flowsheet was established based on experiments in a 0.1t/d pilot plant, including sequential dilute acid and alkali pretreatment, and separate hydrolysis and fermentation (SHF). EP approached a more reliable value through the hierarchical 4-level EP. The heating energy was reduced considerably by HI. The product value was estimated at $0.8-$1.3/kg of equivalent bioethanol. It was suggested through sensitivity analysis that a large plant size, enhanced production yields, and capital cost reduction were necessary for the lignocellulosic bioethanol production to be profitable. Copyright © 2015 Elsevier Ltd. All rights reserved.

  15. Pretreatment of lignocellulosic materials for efficient bioethanol production.

    PubMed

    Galbe, Mats; Zacchi, Guido

    2007-01-01

    Second-generation bioethanol produced from various lignocellulosic materials, such as wood, agricultural or forest residues, has the potential to be a valuable substitute for, or a complement to, gasoline. One of the crucial steps in the ethanol production is the hydrolysis of the hemicellulose and cellulose to monomer sugars. The most promising method for hydrolysis of cellulose to glucose is by use of enzymes, i.e. cellulases. However, in order to make the raw material accessible to the enzymes some kind of pretreatment is necessary. During the last few years a large number of pretreatment methods have been developed, comprising methods working at low pH, i.e. acid based, medium pH (without addition of catalysts), and high pH, i.e. with a base as catalyst. Many methods have been shown to result in high sugar yields, above 90% of theoretical for agricultural residues, especially for corn stover. For more recalcitrant materials, e.g. softwood, acid hydrolysis and steam pretreatment with acid catalyst seem to be the methods that can be used to obtain high sugar and ethanol yields. However, for more accurate comparison of different pretreatment methods it is necessary to improve the assessment methods under real process conditions. The whole process must be considered when a performance evaluation is to be made, as the various pretreatment methods give different types of materials. (Hemicellulose sugars can be obtained either in the liquid as monomer or oligomer sugars, or in the solid material to various extents; lignin can be either in the liquid or remain in the solid part; the composition and amount/concentration of possible inhibitory compounds also vary.) This will affect how the enzymatic hydrolysis should be performed (e.g. with or without hemicellulases), how the lignin is recovered and also the use of the lignin co-product.

  16. Proteome responses to nitrate in bioethanol production contaminant Dekkera bruxellensis.

    PubMed

    Neto, Adauto Gomes Barbosa; Pestana-Calsa, Maria Clara; de Morais, Marcos Antonio; Calsa, Tercilio

    2014-06-02

    Dekkera bruxellensis is an industrially relevant yeast, especially in bioethanol production. The capacity of D. bruxellensis to assimilate nitrate can confer advantages of this yeast over Saccharomyces cerevisiae at industrial conditions. In the present work we present the consequences of nitrate assimilation, using ammonium as reference, to the proteomics of D. bruxellensis. Thirty-four protein spots were overproduced in nitrate medium and were identified by MS-TOF/TOF analysis and were putatively identified by using local Mascot software. Apart from the overexpression of genes of nitrate metabolism, ATP synthesis and PPP and TCA pathways previously reported, cultivation on nitrate induced overproduction of glycolytic enzymes, which corroborate the high energy demand and NADH availability for nitrate assimilation. Overproduction of alcohol dehydrogenase (Adh) protein was also observed. Proteomic profile of D. bruxellensis cultivated in nitrate and described in the present work agrees with the hypothesis of metabolic flux regulation, making available the energy in the form of NADH to support nitrate assimilation. This work contributes with an initial picture of proteins presenting differential accumulation in industrial contaminant yeast, in strict association with possible metabolic responses to nitrate as sole nitrogen source in cultivation medium. The present study investigated the gene expression at translational level of yeast D. bruxellensis for nitrate assimilation. This study corroborated with biological models that consider the ability to assimilate this nitrogen source confers advantages on this yeast during the fermentation process industry. However, larger studies are needed in this way as our group is investigating new proteins under LC-MS/MS approach. Together, these studies will help in understanding the operation of networks and cellular regulation of the process of assimilation of nitrogen sources for the D. bruxellensis, unravelling new aspects of

  17. Community Colleges and Parental Influence in the College Choice Process.

    ERIC Educational Resources Information Center

    Beyer, David; Feller, Rich

    1991-01-01

    Discusses parental influence in college choice process, particularly in terms of considering community colleges as alternative. Argues that there is too little importance given to college choice making, that parents are more significant in the process than assumed, and that community colleges deserve and will receive increasingly more attention…

  18. Response surface optimization of the thermal acid pretreatment of sugar beet pulp for bioethanol production using Trichoderma viride and Saccharomyces cerevisiae.

    PubMed

    El-Gendy, Nour Sh; Madian, Hekmat R; Nassar, Hussein N; Amr, Salem S Abu

    2015-09-15

    Worldwide nowadays, relying on the second generation bioethanol from the lignocellulosic feedstock is a mandatory aim. However, one of the major drawbacks for high ethanol yield is the physical and chemical pretreatment of this kind of feedstock. As the pretreatment is a crucial process operation that modifies the lignocellulosic structure and enhances its accessibility for the high cost hydrolytic enzymes in an attempt to maximize the yield of the fermentable sugars. The objective of this work was to optimize and integrate a physicochemical pretreatment of one of the major agricultural wastes in Egypt; the sugar beet pulp (SBP) and the enzymatic saccharification of the pretreated SBP using a whole fungal cells with a separate bioethanol fermentation batch processes to maximize the bioethanol yield. The response surface methodology was employed in this study to statistically evaluate and optimize the conditions for a thermal acid pretreatment of SBP. The significance and the interaction effects of the concentrations of HCl and SBP and the reaction temperature and time were studied using a three-level central composite design of experiments. A quadratic model equation was obtained to maximize the production of the total reducing sugars. The validity of the predicted model was confirmed. The thermally acid pretreated SBP was further subjected to a solid state fermentation batch process using Trichoderma viride F94. The thermal acid pretreatment and fungal hydrolyzes were integrated with two parallel batch fermentation processes of the produced hydrolyzates using Saccharomyces cerevisiae Y39, that yielded a total of ≈ 48 g/L bioethanol, at a conversion rate of ≈ 0.32 g bioethanol/ g SBP. Applying the proposed integrated process, approximately 97.5 gallon of ethanol would be produced from a ton (dry weight) of SBP.

  19. Response surface optimization of the thermal acid pretreatment of sugar beet pulp for bioethanol production using Trichoderma viride and Saccharomyces cerevisiae.

    PubMed

    El-Gendy, Nour Sh; Madian, Hekmat R; Nassar, Hussein N; Abu Amr, Salem S

    2015-01-01

    Worldwide nowadays, relying on the second generation bioethanol from the lignocellulosic feedstock is a mandatory aim. However, one of the major drawbacks for high ethanol yield is the physical and chemical pretreatment of this kind of feedstock. As the pretreatment is a crucial process operation that modifies the lignocellulosic structure and enhances its accessibility for the high cost hydrolytic enzymes in an attempt to maximize the yield of the fermentable sugars. The objective of this work was to optimize and integrate a physicochemical pretreatment of one of the major agricultural wastes in Egypt; the sugar beet pulp (SBP) and the enzymatic saccharification of the pretreated SBP using a whole fungal cells with a separate bioethanol fermentation batch processes to maximize the bioethanol yield. The response surface methodology was employed in this study to statistically evaluate and optimize the conditions for a thermal acid pretreatment of SBP. The significance and the interaction effects of the concentrations of HCl and SBP and the reaction temperature and time were studied using a three-level central composite design of experiments. A quadratic model equation was obtained to maximize the production of the total reducing sugars. The validity of the predicted model was confirmed. The thermally acid pretreated SBP was further subjected to a solid state fermentation batch process using Trichoderma viride F94. The thermal acid pretreatment and fungal hydrolyzes were integrated with two parallel batch fermentation processes of the produced hydrolyzates using Saccharomyces cerevisiae Y39, that yielded a total of ≈ 48 g/L bioethanol, at a conversion rate of ≈ 0.32 g bioethanol/ g SBP. Applying the proposed integrated process, approximately 97.5 gallon of ethanol would be produced from a ton (dry weight) of SBP.

  20. A simple method to determine bioethanol content in gasoline using two-step extraction and liquid scintillation counting.

    PubMed

    Yunoki, Shunji; Saito, Masaaki

    2009-12-01

    A simple method for determining bioethanol content in gasoline containing bioethanol (denoted as E-gasoline in this study) is urgently required. Liquid scintillation counting (LSC) was employed based on the principle that (14)C exists in bioethanol but not in synthetic ethanol. Bioethanol was extracted in two steps by water from E-gasoline containing 3% (E3) or 10% (E10) bioethanol. The (14)C radioactivity was measured by LSC and converted to the amount of bioethanol. The bioethanol content in E-gasoline was determined precisely from the partition coefficient in the extraction and the amount of bioethanol in the water phases: 2.98+/-0.10% for E3 and 10.0+/-0.1% for E10 (means+/-SD; n=3). It appears that this method can be used to determine bioethanol content in E-gasoline quickly and easily.

  1. Selection of yeast strains for bioethanol production from UK seaweeds.

    PubMed

    Kostas, Emily T; White, Daniel A; Du, Chenyu; Cook, David J

    Macroalgae (seaweeds) are a promising feedstock for the production of third generation bioethanol, since they have high carbohydrate contents, contain little or no lignin and are available in abundance. However, seaweeds typically contain a more diverse array of monomeric sugars than are commonly present in feedstocks derived from lignocellulosic material which are currently used for bioethanol production. Hence, identification of a suitable fermentative microorganism that can utilise the principal sugars released from the hydrolysis of macroalgae remains a major objective. The present study used a phenotypic microarray technique to screen 24 different yeast strains for their ability to metabolise individual monosaccharides commonly found in seaweeds, as well as hydrolysates following an acid pre-treatment of five native UK seaweed species (Laminaria digitata, Fucus serratus, Chondrus crispus, Palmaria palmata and Ulva lactuca). Five strains of yeast (three Saccharomyces spp, one Pichia sp and one Candida sp) were selected and subsequently evaluated for bioethanol production during fermentation of the hydrolysates. Four out of the five selected strains converted these monomeric sugars into bioethanol, with the highest ethanol yield (13 g L(-1)) resulting from a fermentation using C. crispus hydrolysate with Saccharomyces cerevisiae YPS128. This study demonstrated the novel application of a phenotypic microarray technique to screen for yeast capable of metabolising sugars present in seaweed hydrolysates; however, metabolic activity did not always imply fermentative production of ethanol.

  2. Over production of fermentable sugar for bioethanol production from carbohydrate-rich Malaysian food waste via sequential acid-enzymatic hydrolysis pretreatment.

    PubMed

    Hafid, Halimatun Saadiah; Nor 'Aini, Abdul Rahman; Mokhtar, Mohd Noriznan; Talib, Ahmad Tarmezee; Baharuddin, Azhari Samsu; Umi Kalsom, Md Shah

    2017-09-01

    In Malaysia, the amount of food waste produced is estimated at approximately 70% of total municipal solid waste generated and characterised by high amount of carbohydrate polymers such as starch, cellulose, and sugars. Considering the beneficial organic fraction contained, its utilization as an alternative substrate specifically for bioethanol production has receiving more attention. However, the sustainable production of bioethanol from food waste is linked to the efficient pretreatment needed for higher production of fermentable sugar prior to fermentation. In this work, a modified sequential acid-enzymatic hydrolysis process has been developed to produce high concentration of fermentable sugars; glucose, sucrose, fructose and maltose. The process started with hydrothermal and dilute acid pretreatment by hydrochloric acid (HCl) and sulphuric acid (H2SO4) which aim to degrade larger molecules of polysaccharide before accessible for further steps of enzymatic hydrolysis by glucoamylase. A kinetic model is proposed to perform an optimal hydrolysis for obtaining high fermentable sugars. The results suggested that a significant increase in fermentable sugar production (2.04-folds) with conversion efficiency of 86.8% was observed via sequential acid-enzymatic pretreatment as compared to dilute acid pretreatment (∼42.4% conversion efficiency). The bioethanol production by Saccharomyces cerevisiae utilizing fermentable sugar obtained shows ethanol yield of 0.42g/g with conversion efficiency of 85.38% based on the theoretical yield was achieved. The finding indicates that food waste can be considered as a promising substrate for bioethanol production. Copyright © 2017. Published by Elsevier Ltd.

  3. Two-steps microwave-assisted treatment on acid hydrolysis of sago pith for bioethanol production

    NASA Astrophysics Data System (ADS)

    Sunarti, T. C.; Yanti, S. D.; Ruriani, E.

    2017-05-01

    Sago is a genus of palm that can be utilized to produce fermentable sugars as substrate for bioethanol. Sago pith is a heterogeneous substrate consists of starch and fiber. Acid hydrolysis by microwave heating radiation can break down starch and fibers together in a very short time, so it is considered to be very efficient process. The use of microwave energy (as power level) and variation of heating time can produce fermentable sugar with certain characteristics. This study included the preparation and analysis of sago pith flour; process of acid hydrolysis (0.3 M and 0.5 M H2SO4) using two steps microwave heating, first with power level 30% (1, 2 and 3 min) and second with power level 70% (3 min); and ethanol production. The conventional treatment (autoclaving at 121°C for 15 min) was carried for the comparison. The highest fermentable sugar (105.7 g/l) was resulted from microwave heating with power level 30% for 2 min followed by the power level 70% for 3 min. This hydrolyzate then used as substrate for bioethanol fermentation and partially neutralized (pH 3, 4, 5) by using yeast Issatchenkia orientalis, and the highest ethanol (2.8 g/l) was produced in pH 5.

  4. A review of biological delignification and detoxification methods for lignocellulosic bioethanol production.

    PubMed

    Moreno, Antonio D; Ibarra, David; Alvira, Pablo; Tomás-Pejó, Elia; Ballesteros, Mercedes

    2015-01-01

    Future biorefineries will integrate biomass conversion processes to produce fuels, power, heat and value-added chemicals. Due to its low price and wide distribution, lignocellulosic biomass is expected to play an important role toward this goal. Regarding renewable biofuel production, bioethanol from lignocellulosic feedstocks is considered the most feasible option for fossil fuels replacement since these raw materials do not compete with food or feed crops. In the overall process, lignin, the natural barrier of the lignocellulosic biomass, represents an important limiting factor in biomass digestibility. In order to reduce the recalcitrant structure of lignocellulose, biological pretreatments have been promoted as sustainable and environmentally friendly alternatives to traditional physico-chemical technologies, which are expensive and pollute the environment. These approaches include the use of diverse white-rot fungi and/or ligninolytic enzymes, which disrupt lignin polymers and facilitate the bioconversion of the sugar fraction into ethanol. As there is still no suitable biological pretreatment technology ready to scale up in an industrial context, white-rot fungi and/or ligninolytic enzymes have also been proposed to overcome, in a separated or in situ biodetoxification step, the effect of the inhibitors produced by non-biological pretreatments. The present work reviews the latest studies regarding the application of different microorganisms or enzymes as useful and environmentally friendly delignification and detoxification technologies for lignocellulosic biofuel production. This review also points out the main challenges and possible ways to make these technologies a reality for the bioethanol industry.

  5. Construction of novel Saccharomyces cerevisiae strains for bioethanol active dry yeast (ADY) production.

    PubMed

    Zheng, Daoqiong; Zhang, Ke; Gao, Kehui; Liu, Zewei; Zhang, Xing; Li, Ou; Sun, Jianguo; Zhang, Xiaoyang; Du, Fengguang; Sun, Peiyong; Qu, Aimin; Wu, Xuechang

    2013-01-01

    The application of active dry yeast (ADY) in bioethanol production simplifies operation processes and reduces the risk of bacterial contamination. In the present study, we constructed a novel ADY strain with improved stress tolerance and ethanol fermentation performances under stressful conditions. The industrial Saccharomyces cerevisiae strain ZTW1 showed excellent properties and thus subjected to a modified whole-genome shuffling (WGS) process to improve its ethanol titer, proliferation capability, and multiple stress tolerance for ADY production. The best-performing mutant, Z3-86, was obtained after three rounds of WGS, producing 4.4% more ethanol and retaining 2.15-fold higher viability than ZTW1 after drying. Proteomics and physiological analyses indicated that the altered expression patterns of genes involved in protein metabolism, plasma membrane composition, trehalose metabolism, and oxidative responses contribute to the trait improvement of Z3-86. This work not only successfully developed a novel S. cerevisiae mutant for application in commercial bioethanol production, but also enriched the current understanding of how WGS improves the complex traits of microbes.

  6. Solid acid catalysts pretreatment and enzymatic hydrolysis of macroalgae cellulosic residue for the production of bioethanol.

    PubMed

    Tan, Inn Shi; Lee, Keat Teong

    2015-06-25

    The aim of this study is to investigate the technical feasibility of converting macroalgae cellulosic residue (MCR) into bioethanol. An attempt was made to present a novel, environmental friendly and economical pretreatment process that enhances enzymatic conversion of MCR to sugars using Dowex (TM) Dr-G8 as catalyst. The optimum yield of glucose reached 99.8% under the optimal condition for solid acid pretreatment (10%, w/v biomass loading, 4%, w/v catalyst loading, 30min, 120°C) followed by enzymatic hydrolysis (45FPU/g of cellulase, 52CBU/g of β-glucosidase, 50°C, pH 4.8, 30h). The yield of sugar obtained was found more superior than conventional pretreatment process using H2SO4 and NaOH. Biomass loading for the subsequent simultaneous saccharification and fermentation (SSF) of the pretreated MCR was then optimized, giving an optimum bioethanol yield of 81.5%. The catalyst was separated and reused for six times, with only a slight drop in glucose yield. Copyright © 2015 Elsevier Ltd. All rights reserved.

  7. Construction of Novel Saccharomyces cerevisiae Strains for Bioethanol Active Dry Yeast (ADY) Production

    PubMed Central

    Gao, Kehui; Liu, Zewei; Zhang, Xing; Li, Ou; Sun, Jianguo; Zhang, Xiaoyang; Du, Fengguang; Sun, Peiyong; Qu, Aimin; Wu, Xuechang

    2013-01-01

    The application of active dry yeast (ADY) in bioethanol production simplifies operation processes and reduces the risk of bacterial contamination. In the present study, we constructed a novel ADY strain with improved stress tolerance and ethanol fermentation performances under stressful conditions. The industrial Saccharomyces cerevisiae strain ZTW1 showed excellent properties and thus subjected to a modified whole-genome shuffling (WGS) process to improve its ethanol titer, proliferation capability, and multiple stress tolerance for ADY production. The best-performing mutant, Z3-86, was obtained after three rounds of WGS, producing 4.4% more ethanol and retaining 2.15-fold higher viability than ZTW1 after drying. Proteomics and physiological analyses indicated that the altered expression patterns of genes involved in protein metabolism, plasma membrane composition, trehalose metabolism, and oxidative responses contribute to the trait improvement of Z3-86. This work not only successfully developed a novel S. cerevisiae mutant for application in commercial bioethanol production, but also enriched the current understanding of how WGS improves the complex traits of microbes. PMID:24376860

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

    PubMed

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

    2014-09-01

    A practical process was developed for production of a high quality hydrolysate of waste newspaper that ensured its complete fermentability to bioethanol. After pretreatment with 0.1N NaOH for 12h and sequential acid and enzyme hydrolysis, 10.1g/L of glucose (50.5%), 1.38 g/L of mannose (6.9%) and 0.28 g/L of galactose (1.4%), a total of 11.76 g/L of fermentable sugars was obtained, which accounts for 88.7% of saccharification efficiency. The Saccharomyces cerevisiae BCRC20271 showed excellent co-fermentability of glucose, mannose and galactose in hydrolysate of waste newspaper. After cultivation of the hydrolysate at 24°C in static culture for 48 h, the final ethanol concentration of 5.72 g/L (96% conversion efficiency) was produced. Overall, 1000 kg of waste newspaper will produce 286 kg (362 L) of ethanol by the process developed, which reveals that waste newspaper has higher potential than many other lignocellulosic and seaweed feedstocks for bioethanol production. Copyright © 2014 Elsevier Ltd. All rights reserved.

  9. Sequential acid and enzymatic hydrolysis in situ and bioethanol production from Gracilaria biomass.

    PubMed

    Wu, Fang-Chen; Wu, Jane-Yii; Liao, Yi-Jyun; Wang, Man-Ying; Shih, Ing-Lung

    2014-03-01

    Gracilaria sp., a red alga, was used as a feedstock for the production of bioethanol. Saccharification of Gracilaria sp. by sequential acid and enzyme hydrolysis in situ produced a high quality hydrolysate that ensured its fermentability to produce ethanol. The optimal saccharification process resulted in total 11.85g/L (59.26%) of glucose and galactose, Saccharomyces cerevisiae Wu-Y2 showed a good performance on co-fermentability of glucose and galactose released in the hydrolysate from Gracilaria sp. The final ethanol concentrations of 4.72g/L (0.48g/g sugar consumed; 94% conversion efficiency) and the ethanol productivity 4.93g/L/d were achieved. 1g of dry Gracilaria can be converted to 0.236g (23.6%) of bioethanol via the processes developed. Efficient alcohol production by immobilized S. cerevisiae Wu-Y2 in batch and repeated batch fermentation was also demonstrated. The findings of this study revealed that Gracilaria sp. can be a potential feedstock in biorefinery for ethanol production.

  10. Tannin extraction pretreatment and very high gravity fermentation of acorn starch for bioethanol production.

    PubMed

    Chao, Bin; Liu, Ruiliang; Zhang, Xueling; Zhang, Xu; Tan, Tianwei

    2017-10-01

    The bioethanol production from a novel non-grain feedstock, acorn starch, was studied in this work. The inhibition of tannin in strain growth was investigated, and the effect of tannin was negligible when the tannin concentration was lower than 1g/L in medium. Therefore, the extraction of tannin was performed using 40% (v/v) ethanol-water solution as the solvent for three times under the conditions of solid/liquid ratio 1:20, 60°C, 3h, by which more than 80% of tannin in acorn was extracted and the content of tannin in acorn decreased from 7.4% (w/w) to 1.5% (w/w). Very high gravity (VHG) fermentation technology was subsequently carried out to achieve a high ethanol concentration at 86.4g/L. A comprehensive process for bioethanol production from acorn starch was designed and a preliminary economic assessment was then performed revealing that this process appeared technically and economically justified. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. Estimating and mapping ecological processes influencing microbial community assembly

    PubMed Central

    Stegen, James C.; Lin, Xueju; Fredrickson, Jim K.; Konopka, Allan E.

    2015-01-01

    Ecological community assembly is governed by a combination of (i) selection resulting from among-taxa differences in performance; (ii) dispersal resulting from organismal movement; and (iii) ecological drift resulting from stochastic changes in population sizes. The relative importance and nature of these processes can vary across environments. Selection can be homogeneous or variable, and while dispersal is a rate, we conceptualize extreme dispersal rates as two categories; dispersal limitation results from limited exchange of organisms among communities, and homogenizing dispersal results from high levels of organism exchange. To estimate the influence and spatial variation of each process we extend a recently developed statistical framework, use a simulation model to evaluate the accuracy of the extended framework, and use the framework to examine subsurface microbial communities over two geologic formations. For each subsurface community we estimate the degree to which it is influenced by homogeneous selection, variable selection, dispersal limitation, and homogenizing dispersal. Our analyses revealed that the relative influences of these ecological processes vary substantially across communities even within a geologic formation. We further identify environmental and spatial features associated with each ecological process, which allowed mapping of spatial variation in ecological-process-influences. The resulting maps provide a new lens through which ecological systems can be understood; in the subsurface system investigated here they revealed that the influence of variable selection was associated with the rate at which redox conditions change with subsurface depth. PMID:25983725

  12. Estimating and mapping ecological processes influencing microbial community assembly

    DOE PAGES

    Stegen, James C.; Lin, Xueju; Fredrickson, Jim K.; ...

    2015-05-01

    Ecological community assembly is governed by a combination of (i) selection resulting from among-taxa differences in performance; (ii) dispersal resulting from organismal movement; and (iii) ecological drift resulting from stochastic changes in population sizes. The relative importance and nature of these processes can vary across environments. Selection can be homogeneous or variable, and while dispersal is a rate, we conceptualize extreme dispersal rates as two categories; dispersal limitation results from limited exchange of organisms among communities, and homogenizing dispersal results from high levels of organism exchange. To estimate the influence and spatial variation of each process we extend a recentlymore » developed statistical framework, use a simulation model to evaluate the accuracy of the extended framework, and use the framework to examine subsurface microbial communities over two geologic formations. For each subsurface community we estimate the degree to which it is influenced by homogeneous selection, variable selection, dispersal limitation, and homogenizing dispersal. Our analyses revealed that the relative influences of these ecological processes vary substantially across communities even within a geologic formation. We further identify environmental and spatial features associated with each ecological process, which allowed mapping of spatial variation in ecological-process-influences. The resulting maps provide a new lens through which ecological systems can be understood; in the subsurface system investigated here they revealed that the influence of variable selection was associated with the rate at which redox conditions change with subsurface depth.« less

  13. Estimating and mapping ecological processes influencing microbial community assembly

    SciTech Connect

    Stegen, James C.; Lin, Xueju; Fredrickson, Jim K.; Konopka, Allan E.

    2015-05-01

    Ecological community assembly is governed by a combination of (i) selection resulting from among-taxa differences in performance; (ii) dispersal resulting from organismal movement; and (iii) ecological drift resulting from stochastic changes in population sizes. The relative importance and nature of these processes can vary across environments. Selection can be homogeneous or variable, and while dispersal is a rate, we conceptualize extreme dispersal rates as two categories; dispersal limitation results from limited exchange of organisms among communities, and homogenizing dispersal results from high levels of organism exchange. To estimate the influence and spatial variation of each process we extend a recently developed statistical framework, use a simulation model to evaluate the accuracy of the extended framework, and use the framework to examine subsurface microbial communities over two geologic formations. For each subsurface community we estimate the degree to which it is influenced by homogeneous selection, variable selection, dispersal limitation, and homogenizing dispersal. Our analyses revealed that the relative influences of these ecological processes vary substantially across communities even within a geologic formation. We further identify environmental and spatial features associated with each ecological process, which allowed mapping of spatial variation in ecological-process-influences. The resulting maps provide a new lens through which ecological systems can be understood; in the subsurface system investigated here they revealed that the influence of variable selection was associated with the rate at which redox conditions change with subsurface depth.

  14. Direct bioethanol production by amylolytic yeast Candida albicans.

    PubMed

    Aruna, A; Nagavalli, M; Girijashankar, V; Ponamgi, S P D; Swathisree, V; Rao, L Venkateswar

    2015-03-01

    An attempt was made to produce bioethanol using optimized fermentation parameters and mutationally improved strain of Candida albicans. The mutant strain OMC3E6 obtained by UV irradiation followed by ethidium bromide successive mutations showed 2.6 times more glucoamylase secretion and 1.5 times more bioethanol production via direct conversion of starch. Enhanced hydrolysis of insoluble starch (72%) and potato starch (70%) was achieved with glucoamylase enzyme preparation from mutant C. albicans. In fermentation medium, the use of maltose, corn steep liquor, NaH2 PO4 , NaCl + MgSO4 and Triton X-100 has increased the glucoamylase production by the microbe. Under optimized conditions, C. albicans eventually produced 437 g ethanol kg(-1) potatoes. Earlier reports mentioned the use of thrice the quantity of starch as reported by us followed by more fermentation period (3-4 days) and demanded pretreatment of starch sources with alpha-amylase as well. Here, we simplified these three steps and obtained 73% conversion of insoluble starch into ethanol via direct conversion method in a period of 2 days without the involvement of cell immobilizations or enzyme pretreatment steps. Due to fast depletion of fossil fuels in the modern world, bioethanol usage as an alternate energy source is the need of the hour. For the first time, we report bioethanol production by Candida albicans via direct conversion of starchy biomass into ethanol along with enhanced starch-hydrolysing capacity and ethanol conversion ratio. So far, C. albicans was dealt in the field of clinical pathology, but here we successfully employed this organism to produce bioethanol from starchy agri-substrates. Optimizing fermentation parameters and improving the microbial strains through successive mutagenesis can improve the end product yield. © 2014 The Society for Applied Microbiology.

  15. Mutual influences of pain and emotional face processing.

    PubMed

    Wieser, Matthias J; Gerdes, Antje B M; Reicherts, Philipp; Pauli, Paul

    2014-01-01

    The perception of unpleasant stimuli enhances whereas the perception of pleasant stimuli decreases pain perception. In contrast, the effects of pain on the processing of emotional stimuli are much less known. Especially given the recent interest in facial expressions of pain as a special category of emotional stimuli, a main topic in this research line is the mutual influence of pain and facial expression processing. Therefore, in this mini-review we selectively summarize research on the effects of emotional stimuli on pain, but more extensively turn to the opposite direction namely how pain influences concurrent processing of affective stimuli such as facial expressions. Based on the motivational priming theory one may hypothesize that the perception of pain enhances the processing of unpleasant stimuli and decreases the processing of pleasant stimuli. This review reveals that the literature is only partly consistent with this assumption: pain reduces the processing of pleasant pictures and happy facial expressions, but does not - or only partly - affect processing of unpleasant pictures. However, it was demonstrated that pain selectively enhances the processing of facial expressions if these are pain-related (i.e., facial expressions of pain). Extending a mere affective modulation theory, the latter results suggest pain-specific effects which may be explained by the perception-action model of empathy. Together, these results underscore the important mutual influence of pain and emotional face processing.

  16. Mutual influences of pain and emotional face processing

    PubMed Central

    Wieser, Matthias J.; Gerdes, Antje B. M.; Reicherts, Philipp; Pauli, Paul

    2014-01-01

    The perception of unpleasant stimuli enhances whereas the perception of pleasant stimuli decreases pain perception. In contrast, the effects of pain on the processing of emotional stimuli are much less known. Especially given the recent interest in facial expressions of pain as a special category of emotional stimuli, a main topic in this research line is the mutual influence of pain and facial expression processing. Therefore, in this mini-review we selectively summarize research on the effects of emotional stimuli on pain, but more extensively turn to the opposite direction namely how pain influences concurrent processing of affective stimuli such as facial expressions. Based on the motivational priming theory one may hypothesize that the perception of pain enhances the processing of unpleasant stimuli and decreases the processing of pleasant stimuli. This review reveals that the literature is only partly consistent with this assumption: pain reduces the processing of pleasant pictures and happy facial expressions, but does not – or only partly – affect processing of unpleasant pictures. However, it was demonstrated that pain selectively enhances the processing of facial expressions if these are pain-related (i.e., facial expressions of pain). Extending a mere affective modulation theory, the latter results suggest pain-specific effects which may be explained by the perception-action model of empathy. Together, these results underscore the important mutual influence of pain and emotional face processing. PMID:25352817

  17. Fractionation of oil palm empty fruit bunch by bisulfite pretreatment for the production of bioethanol and high value products.

    PubMed

    Tan, Liping; Wang, Meimei; Li, Xuezhi; Li, Hongxing; Zhao, Jian; Qu, Yinbo; Choo, Yuen May; Loh, Soh Kheang

    2016-01-01

    In this work, fractionation of empty fruit bunch (EFB) by bisulfite pretreatment was studied for the production of bioethanol and high value products to achieve biorefinery of EFB. EFB was fractionated to solid and liquor components by bisulfite process. The solid components were used for bioethanol production by quasi-simultaneous saccharification and fermentation. The liquor components were then converted to furfural by hydrolysis with sulfuric acid. Preliminary results showed that the concentration of furfural was highest at 18.8g/L with 0.75% sulfuric acid and reaction time of 25min. The conversion of xylose to furfural was 82.5%. Furthermore, we attempted to fractionate the liquor into hemicellulose sugars and lignin by different methods for producing potential chemicals, such as xylose, xylooligosaccharide, and lignosulfonate. Our research showed that the combination of bisulfite pretreatment and resin separation could effectively fractionate EFB components to produce bioethanol and other high value chemicals. Copyright © 2015 Elsevier Ltd. All rights reserved.

  18. High bioethanol titre from Manihot glaziovii through fed-batch simultaneous saccharification and fermentation in Automatic Gas Potential Test System.

    PubMed

    Moshi, Anselm P; Crespo, Carla F; Badshah, Malik; Hosea, Kenneth M M; Mshandete, Anthony Manoni; Mattiasson, Bo

    2014-03-01

    A process for the production of high bioethanol titre was established through fed-batch and simultaneous saccharification and fermentation (FB-SSF) of wild, non-edible cassava Manihot glaziovii. FB-SSF allowed fermentation of up to 390g/L of starch-derived glucose achieving high bioethanol concentration of up to 190g/L (24% v/v) with yields of around 94% of the theoretical value. The wild cassava M. glaziovii starch is hydrolysable with a low dosage of amylolytic enzymes (0.1-0.15% v/w, Termamyl® and AMG®). The Automatic Gas Potential Test System (AMPTS) was adapted to yeast ethanol fermentation and demonstrated to be an accurate, reliable and flexible device for studying the kinetics of yeast in SSF and FB-SSF. The bioethanol derived stoichiometrically from the CO2 registered in the AMPTS software correlated positively with samples analysed by HPLC (R(2)=0.99). Copyright © 2013 Elsevier Ltd. All rights reserved.

  19. Spray automated balancing of rotors - How process parameters influence performance

    NASA Technical Reports Server (NTRS)

    Smalley, A. J.; Baldwin, R. M.; Fleming, D. P.; Yuhas, J. S.

    1989-01-01

    This paper addresses the application of spray-automated balancing of rotors, and the influence that various operating parameters will have on balancing performance. Spray-automated balancing uses the fuel-air repetitive explosion process to imbed short, discrete bursts of high velocity, high temperature powder into a rotating part at an angle selected to reduce unbalance of the part. The shortness of the burst, the delay in firing of the gun, the speed of the disk and the variability in speed all influence the accuracy and effectiveness of the automated balancing process. The paper evaluates this influence by developing an analytical framework and supplementing the analysis with empirical data obtained while firing the gun at a rotating disk. Encouraging results are obtained, and it is shown that the process should perform satisfactorily over a wide range of operating parameters. Further experimental results demonstrate the ability of the method to reduce vibration levels induced by mass unbalance in a rotating disk.

  20. Eco-social processes influencing infectious disease emergence and spread.

    PubMed

    Jones, Bryony A; Betson, Martha; Pfeiffer, Dirk U

    2017-01-01

    The complexity and connectedness of eco-social processes have major influence on the emergence and spread of infectious diseases amongst humans and animals. The disciplinary nature of most research activity has made it difficult to improve our understanding of interactions and feedback loops within the relevant systems. Influenced by the One Health approach, increasing efforts have recently been made to address this knowledge gap. Disease emergence and spread is strongly influenced by host density and contact structures, pathogen characteristics and pathogen population and molecular evolutionary dynamics in different host species, and host response to infection. All these mechanisms are strongly influenced by eco-social processes, such as globalization and urbanization, which lead to changes in global ecosystem dynamics, including patterns of mobility, human population density and contact structures, and food production and consumption. An improved understanding of epidemiological and eco-social processes, including their interdependence, will be essential to be able to manage diseases in these circumstances. The interfaces between wild animals, domestic animals and humans need to be examined to identify the main risk pathways and put in place appropriate mitigation. Some recent examples of emerging infectious disease are described to illustrate eco-social processes that are influencing disease emergence and spread.

  1. Combustion parameters of spark ignition engine using waste potato bioethanol and gasoline blended fuels

    NASA Astrophysics Data System (ADS)

    Ghobadian, B.; Najafi, G.; Abasian, M.; Mamat, R.

    2015-12-01

    The purpose of this study is to investigate the combustion parameters of a SI engine operating on bioethanol-gasoline blends (E0-E20: 20% bioethanol and 80% gasoline by volume). A reactor was designed, fabricated and evaluated for bioethanol production from potato wastes. The results showed that increasing the bioethanol content in the blend fuel will decrease the heating value of the blended fuel and increase the octane number. Combustion parameters were evaluated and analyzed at different engine speeds and loads (1000-5000 rpm). The results revealed that using bioethanol-gasoline blended fuels will increase the cylinder pressure and its 1st and 2nd derivatives (P(θ), P•(θ) and P••(θ)). Moreover, using bioethanol- gasoline blends will increase the heat release (Q•(θ)) and worked of the cycle. This improvement was due to the high oxygen percentage in the ethanol.

  2. Impact of bioethanol fuel implementation in transport based on modelled acetaldehyde concentration in the urban environment.

    PubMed

    Sundvor, Ingrid; López-Aparicio, Susana

    2014-10-15

    This study shows the results obtained from emission and air dispersion modelling of acetaldehyde in the city of Oslo and associated with the circulation of bioethanol vehicles. Two scenarios of bioethanol implementation, both realistic and hypothetical, have been considered under winter conditions; 1) realistic baseline scenario, which corresponds to the current situation in Oslo where one bus line is running with bioethanol (E95; 95% ethanol-5% petrol) among petrol and diesel vehicles; and 2) a hypothetical scenario characterized by a full implementation of high-blend bioethanol (i.e. E85) as fuel for transportation, and thus an entire bioethanol fleet. The results indicate that a full implementation of bioethanol will have a certain impact on urban air quality due to direct emissions of acetaldehyde. Acetaldehyde emissions are estimated to increase by 233% and concentration levels increase up to 650% with regard to the baseline.

  3. Life-cycle energy efficiency and environmental impacts of bioethanol production from sweet potato.

    PubMed

    Wang, Mingxin; Shi, Yu; Xia, Xunfeng; Li, Dinglong; Chen, Qun

    2013-04-01

    Life-cycle assessment (LCA) was used to evaluate the energy efficiency and environmental impacts of sweet potato-based bioethanol production. The scope covered all stages in the life cycle of bioethanol production, including the cultivation and treatment, transport, as well as bioethanol conversion of sweet potato. Results show that the net energy ratio of sweet potato-based bioethanol is 1.48 and the net energy gain is 6.55 MJ/L. Eutrophication is identified as the most significant environmental impact category, followed by acidification, global warming, human toxicity, and photochemical oxidation. Sensitivity analysis reveals that steam consumption during bioethanol conversion exerts the most effect on the results, followed by sweet potato yields and fertilizers input. It is suggested that substituting coal with cleaner energy for steam generation in bioethanol conversion stage and promotion of better management practices in sweet potato cultivation stage could lead to a significant improvement of energy and environmental performance.

  4. Optimization of simultaneous saccharification and fermentation conditions with amphipathic lignin derivatives for concentrated bioethanol production.

    PubMed

    Cheng, Ningning; Koda, Keiichi; Tamai, Yutaka; Yamamoto, Yoko; Takasuka, Taichi E; Uraki, Yasumitsu

    2017-05-01

    Amphipathic lignin derivatives (A-LDs) prepared from the black liquor of soda pulping of Japanese cedar are strong accelerators for bioethanol production under a fed-batch simultaneous enzymatic saccharification and fermentation (SSF) process. To improve the bioethanol production concentration, conditions such as reaction temperature, stirring program, and A-LDs loadings were optimized in both small scale and large scale fed-batch SSF. The fed-batch SSF in the presence of 3.0g/L A-LDs at 38°C gave the maximum ethanol production and a high enzyme recovery rate. Furthermore, a jar-fermenter equipped with a powerful mechanical stirrer was designed for 1.5L-scale fed-batch SSF to achieve rigorous mixing during high substrate loading. Finally, the 1.5L fed-batch SSF with a substrate loading of 30% (w/v) produced a high ethanol concentration of 87.9g/L in the presence of A-LDs under optimized conditions. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  5. A Factorial Analysis Study on Enzymatic Hydrolysis of Fiber Pressed Oil Palm Frond for Bioethanol Production

    NASA Astrophysics Data System (ADS)

    Hashim, F. S.; Yussof, H. W.; Zahari, M. A. K. M.; Illias, R. M.; Rahman, R. A.

    2016-03-01

    Different technologies have been developed to for the conversion of lignocellulosic biomass to suitable fermentation substrates for bioethanol production. The enzymatic conversion of cellulose seems to be the most promising technology as it is highly specific and does not produce substantial amounts of unwanted byproducts. The effects of agitation speed, enzyme loading, temperature, pH and reaction time on the conversion of glucose from fiber pressed oil palm frond (FPOPF) for bioethanol production were screened by statistical analysis using response surface methodology (RSM). A half fraction two-level factorial analysis with five factors was selected for the experimental design to determine the best enzymatic conditions that produce maximum amount of glucose. FPOPF was pre-treated with alkaline prior to enzymatic hydrolysis. The enzymatic hydrolysis was performed using a commercial enzyme Cellic CTec2. From this study, the highest yield of glucose concentration was 9.736 g/L at 72 hours reaction time at 35 °C, pH 5.6, and 1.5% (w/v) of enzyme loading. The model obtained was significant with p-value <0.0001. It is suggested that this model had a maximum point which is likely to be the optimum point and possible for the optimization process.

  6. Integrated Production of Xylonic Acid and Bioethanol from Acid-Catalyzed Steam-Exploded Corn Stover.

    PubMed

    Zhu, Junjun; Rong, Yayun; Yang, Jinlong; Zhou, Xin; Xu, Yong; Zhang, Lingling; Chen, Jiahui; Yong, Qiang; Yu, Shiyuan

    2015-07-01

    High-efficiency xylose utilization is one of the restrictive factors of bioethanol industrialization. However, xylonic acid (XA) as a new bio-based platform chemical can be produced by oxidation of xylose with microbial. So, an applicable technology of XA bioconversion was integrated into the process of bioethanol production. After corn stover was pretreated with acid-catalyzed steam-explosion, solid and liquid fractions were obtained. The liquid fraction, also named as acid-catalyzed steam-exploded corn stover (ASC) prehydrolyzate (mainly containing xylose), was catalyzed with Gluconobacter oxydans NL71 to prepare XA. After 72 h of bioconversion of concentrated ASC prehydrolyzate (containing 55.0 g/L of xylose), the XA concentration reached a peak value of 54.97 g/L, the sugar utilization ratio and XA yield were 94.08 and 95.45 %, respectively. The solid fraction was hydrolyzed to produce glucose with cellulase and then fermented with Saccharomyces cerevisiae NL22 to produce ethanol. After 18 h of fermentation of concentrated enzymatic hydrolyzate (containing 86.22 g/L of glucose), the ethanol concentration reached its highest value of 41.48 g/L, the sugar utilization ratio and ethanol yield were 98.72 and 95.25 %, respectively. The mass balance showed that 1 t ethanol and 1.3 t XA were produced from 7.8 t oven dry corn stover.

  7. Separation and characterization of lignin from bio-ethanol production residue.

    PubMed

    Guo, Guowan; Li, Shujun; Wang, Lu; Ren, Shixue; Fang, Guizhen

    2013-05-01

    In order to develop an adequate method to separate lignin from bio-ethanol production residue, solvent extraction was conducted by using benzyl alcohol, dioxane and ethanol. Compared to the conventional alkali-solution and acid-isolation method, benzyl alcohol and dioxane extraction could reach higher lignin yield of 71.55% and 74.14% respectively. FTIR and XRD analysis results indicate that sodium hydroxide solution dissolved most of the lignin in the raw material. However, the low lignin yield by this method may be attributed to the products loss during the complex separation process. GPC and (1)H NMR results revealed that the dioxane-lignin had closer molecular weight with alkali-lignin, lower S/G ratio (0.22) and higher OHPh/OHAl ratio (0.45) with respect to benzyl alcohol-lignin. The results divulge that the lignin products separated from bio-ethanol production residue by dioxane extraction had fairly potential application with better chemical activity. Copyright © 2012 Elsevier Ltd. All rights reserved.

  8. Construction of bioengineered yeast platform for direct bioethanol production from alginate and mannitol.

    PubMed

    Takagi, Toshiyuki; Sasaki, Yusuke; Motone, Keisuke; Shibata, Toshiyuki; Tanaka, Reiji; Miyake, Hideo; Mori, Tetsushi; Kuroda, Kouichi; Ueda, Mitsuyoshi

    2017-07-24

    Brown macroalgae are a sustainable and promising source for bioethanol production because they are abundant in ocean ecosystems and contain negligible quantities of lignin. Brown macroalgae contain cellulose, hemicellulose, mannitol, laminarin, and alginate as major carbohydrates. Among these carbohydrates, brown macroalgae are characterized by high levels of alginate and mannitol. The direct bioconversion of alginate and mannitol into ethanol requires extensive bioengineering of assimilation processes in the standard industrial microbe Saccharomyces cerevisiae. Here, we constructed an alginate-assimilating S. cerevisiae recombinant strain by genome integration and overexpression of the genes encoding endo- and exo-type alginate lyases, DEH (4-deoxy-L-erythro-5-hexoseulose uronic acid) transporter, and components of the DEH metabolic pathway. Furthermore, the mannitol-metabolizing capacity of S. cerevisiae was enhanced by prolonged culture in a medium containing mannitol as the sole carbon source. When the constructed strain AM1 was anaerobically cultivated in a fermentation medium containing 6% (w/v) total sugars (approximately 1:2 ratio of alginate/mannitol), it directly produced ethanol from alginate and mannitol, giving 8.8 g/L ethanol and yields of up to 32% of the maximum theoretical yield from consumed sugars. These results indicate that all major carbohydrates of brown macroalgae can be directly converted into bioethanol by S. cerevisiae. This strain and system could provide a platform for the complete utilization of brown macroalgae.

  9. Comparison of microwave and conduction-convection heating autohydrolysis pretreatment for bioethanol production.

    PubMed

    Aguilar-Reynosa, Alejandra; Romaní, Aloia; Rodríguez-Jasso, Rosa M; Aguilar, Cristóbal N; Garrote, Gil; Ruiz, Héctor A

    2017-06-20

    This work describes the application of two forms of heating for autohydrolysis pretreatment on isothermal regimen: conduction-convection heating and microwave heating processing using corn stover as raw material for bioethanol production. Pretreatments were performed using different operational conditions: residence time (10-50 min) and temperature (160-200°C) for both pretreatments. Subsequently, the susceptibility of pretreated solids was studied using low enzyme loads, and high substrate loads. The highest conversion was 95.1% for microwave pretreated solids. Also solids pretreated by microwave heating processing showed better ethanol conversion in simultaneous saccharification and fermentation process (92% corresponding to 33.8g/L). Therefore, microwave heating processing is a promising technology in the pretreatment of lignocellulosic materials. Copyright © 2017 Elsevier Ltd. All rights reserved.

  10. Processes through which adolescents believe romantic relationships influence friendship quality.

    PubMed

    Thomas, Jennifer J

    2012-01-01

    Little is known about how romantic relationships influence adolescents' friendships. The purpose of this exploratory study was to identify behaviors through which adolescents believe romantic relationships influence friendship quality. Intimate exchange, co-rumination, encouragement, and conflict resolution were identified as processes through which romantic relationships influence friendship quality. Associations between these variables and friendship quality were investigated with 340 adolescents. Adolescents believed these processes occurred frequently within friendship. Gender differences suggest girls may be more sensitive to the influence of romantic partners on their friendships than are boys. Hierarchical regression analyses revealed that greater intimacy, encouragement, compromise, and less co-rumination were associated with more positive beliefs about friendship quality when one friend has a girlfriend or boyfriend. Greater co-rumination and less encouragement were predictive of negative friendship quality. Thus, these processes may represent avenues through which romantic relationships positively and negatively influence friendship quality. Findings highlight the need to understand friendships as part of a complex social network that includes romantic ties.

  11. Peer influence processes for youth delinquency and depression.

    PubMed

    Reynolds, Andrew D; Crea, Thomas M

    2015-08-01

    This study explores the multiple factors that account for peer influence processes of adolescent delinquency and depression using data from Waves I and II of the National Longitudinal Study of Adolescent to Adult Health (Add Health). Random-effects longitudinal negative binomial models were used to predict depression and delinquency, controlling for social connection variables to account for selection bias. Findings suggest peer depression and delinquency are both predictive of youth delinquency, while peer influences of depression are much more modest. Youth who are more connected to parents and communities and who are more popular within their networks are more susceptible to peer influence, while self-regulating youth are less susceptible. We find support for theories of popularity-socialization as well as weak-ties in explaining social network factors that amplify or constrain peer influence. We argue that practitioners working with youth should consider network-informed interventions to improve program efficacy and avoid iatrogenic effects.

  12. The bioethanol industry in sub-Saharan Africa: history, challenges, and prospects.

    PubMed

    Deenanath, Evanie Devi; Iyuke, Sunny; Rumbold, Karl

    2012-01-01

    Recently, interest in using bioethanol as an alternative to petroleum fuel has been escalating due to decrease in the availability of crude oil. The application of bioethanol in the motor-fuel industry can contribute to reduction in the use of fossil fuels and in turn to decreased carbon emissions and stress of the rapid decline in crude oil availability. Bioethanol production methods are numerous and vary with the types of feedstock used. Feedstocks can be cereal grains (first generation feedstock), lignocellulose (second generation feedstock), or algae (third generation feedstock) feedstocks. To date, USA and Brazil are the leading contributors to global bioethanol production. In sub-Saharan Africa, bioethanol production is stagnant. During the 1980s, bioethanol production has been successful in several countries including Zimbabwe, Malawi, and Kenya. However, because of numerous challenges such as food security, land availability, and government policies, achieving sustainability was a major hurdle. This paper examines the history and challenges of bioethanol production in sub-Saharan Africa (SSA) and demonstrates the bioethanol production potential in SSA with a focus on using bitter sorghum and cashew apple juice as unconventional feedstocks for bioethanol production.

  13. The Bioethanol Industry in Sub-Saharan Africa: History, Challenges, and Prospects

    PubMed Central

    Deenanath, Evanie Devi; Iyuke, Sunny; Rumbold, Karl

    2012-01-01

    Recently, interest in using bioethanol as an alternative to petroleum fuel has been escalating due to decrease in the availability of crude oil. The application of bioethanol in the motor-fuel industry can contribute to reduction in the use of fossil fuels and in turn to decreased carbon emissions and stress of the rapid decline in crude oil availability. Bioethanol production methods are numerous and vary with the types of feedstock used. Feedstocks can be cereal grains (first generation feedstock), lignocellulose (second generation feedstock), or algae (third generation feedstock) feedstocks. To date, USA and Brazil are the leading contributors to global bioethanol production. In sub-Saharan Africa, bioethanol production is stagnant. During the 1980s, bioethanol production has been successful in several countries including Zimbabwe, Malawi, and Kenya. However, because of numerous challenges such as food security, land availability, and government policies, achieving sustainability was a major hurdle. This paper examines the history and challenges of bioethanol production in sub-Saharan Africa (SSA) and demonstrates the bioethanol production potential in SSA with a focus on using bitter sorghum and cashew apple juice as unconventional feedstocks for bioethanol production. PMID:22536020

  14. Competing Processes of Sibling Influence: Observational Learning and Sibling Deidentification

    ERIC Educational Resources Information Center

    Whiteman, Shawn D.; McHale, Susan M.; Crouter, Ann C.

    2007-01-01

    Although commonly cited as explanations for patterns of sibling similarity and difference, observational learning and sibling deidentification processes have rarely been examined directly. Using a person-oriented approach, we identified patterns in adolescents' perceptions of sibling influences and connected these patterns to sibling similarities…

  15. Friendship and Delinquency: Selection and Influence Processes in Early Adolescence

    ERIC Educational Resources Information Center

    Knecht, Andrea; Snijders, Tom A. B.; Baerveldt, Chris; Steglich, Christian E. G.; Raub, Werner

    2010-01-01

    Positive association of relevant characteristics is a widespread pattern among adolescent friends. A positive association may be caused by the selection of similar others as friends and by the deselection of dissimilar ones, but also by influence processes where friends adjust their behavior to each other. Social control theory argues that…

  16. The influence of weak impacts on certain processes of nanotechnology

    NASA Astrophysics Data System (ADS)

    Tupik, V. A.; Margolin, V. I.; Potekhin, M. S.

    2017-07-01

    The article deals with the influence of weak and super weak impacts on certain technological processes in nanotechnology related to the synthesis of nanoscale films and coatings. We also touch upon the impacts of weak diffraction fields of complex shape on the formation of fractal films and coatings.

  17. Influence of Appalachian Fatalism on Adolescent Identity Processes

    ERIC Educational Resources Information Center

    Phillips, Tommy M.

    2007-01-01

    The influences of the fatalism frequently associated with Appalachian culture on adolescent identity processes were explored. The sample consisted of 91 Appalachian adolescents and 87 non-Appalachian adolescents. Participants completed measures of fatalism (operationalized in terms of higher hopelessness and lower optimism/efficacy scores) and…

  18. The influence of petroleum products on the methane fermentation process.

    PubMed

    Choromański, Paweł; Karwowska, Ewa; Łebkowska, Maria

    2016-01-15

    In this study the influence of the petroleum products: diesel fuel and spent engine oil on the sewage sludge digestion process and biogas production efficiency was investigated. Microbiological, chemical and enzymatic analyses were applied in the survey. It was revealed that the influence of the petroleum derivatives on the effectiveness of the methane fermentation of sewage sludge depends on the type of the petroleum product. Diesel fuel did not limit the biogas production and the methane concentration in the biogas, while spent engine oil significantly reduced the process efficacy. The changes in physical-chemical parameters, excluding COD, did not reflect the effect of the tested substances. The negative influence of petroleum products on individual bacterial groups was observed after 7 days of the process, while after 14 days probably some adaptive mechanisms appeared. The dehydrogenase activity assessment was the most relevant parameter to evaluate the effect of petroleum products contamination. Diesel fuel was probably used as a source of carbon and energy in the process, while the toxic influence was observed in case of spent engine oil.

  19. Influence of Appalachian Fatalism on Adolescent Identity Processes

    ERIC Educational Resources Information Center

    Phillips, Tommy M.

    2007-01-01

    The influences of the fatalism frequently associated with Appalachian culture on adolescent identity processes were explored. The sample consisted of 91 Appalachian adolescents and 87 non-Appalachian adolescents. Participants completed measures of fatalism (operationalized in terms of higher hopelessness and lower optimism/efficacy scores) and…

  20. Decolorization of black liquor from bioethanol G2 production using iron oxide coating sands

    NASA Astrophysics Data System (ADS)

    Barlianti, Vera; Triwahyuni, Eka; Waluyo, Joko; Sari, Ajeng Arum

    2017-01-01

    Bioethanol G2 production using oil palm empty fruit bunch as raw material consists of four steps, namely pretreatment, hydrolysis, fermentation, and purification process. Pretreatment process generates black liquor that causes serious environmental pollution if it is released to the environment. The objective of this research is studying the ability of iron oxide coating sands to adsorb the color of black liquor. The iron oxide coating sands were synthesized from FeCl3.6H2O with quartz sands as support material. This research was conducted on batch mode using black liquor in various pH values. Result obtained that kind of iron oxide on quartz sands's surface was goethite. The result also indicated decreasing of color intensity of black liquor after adsorption process. This research supports local material utilization in environmental technology development to solve some environmental problems.

  1. Physicochemical interaction and its influence on deep bed filtration process.

    PubMed

    Guo, Jin-long; Meng, Jun; Li, Gui-ping; Luan, Zhao-kun; Tang, Hong-xiao

    2004-01-01

    The capillary model was used to analyze the hydraulic conditions in the deep bed filtration process. The physicochemical interaction forces between the filter media and suspended particles and their influence on deep bed filtration process were also studied theoretically. Through the comparison of the hydraulic and physicochemical forces, the key influencing factors on the filtration process were proposed and investigated. Pilot study of the microflocculation deep bed filtration was carried out in the No. 9 Potable Water Treatment Plant of Beijing, and the experimental results of hydraulic head loss, particle distribution and entrapment were presented. The theoretical prediction was reasonably consistent with the experimental results under different conditions, which indicated that the regulation and control of micro-flocculation and deep bed filtration could be realized by the evaluation of the physicochemical interactions. Further theoretical and experimental research should be carried out to investigate the interaction mechanism and its application in the deep bed filtration and other cases.

  2. Influence of degassing on hot-melt extrusion process.

    PubMed

    Alshahrani, Saad M; Morott, Joseph T; Alshetaili, Abdullah S; Tiwari, Roshan V; Majumdar, Soumyajit; Repka, Michael A

    2015-12-01

    The present study aimed to evaluate the effect of degassing on an extrusion process, with respect to extrudate quality and drug release properties. Processed formulations were extruded with and without a degassing vent port at various locations along the barrel. All the experiments were performed under constant processing temperature, feeding rate, and screw speed. During the extrusion process, torque and pressure were monitored and recorded. The degassing process was beneficial when used over a conveying section after a mixing section. This is attributed to the large surface area available on the conveying elements, which minimizes the internal volume of the processed material, thereby facilitating the escape of entrapped gases. Degassing enhanced the homogeneity, physical appearance, and drug release properties of all the formulations. Furthermore, the degassing process also enhanced the cross-sectional uniformity of the extruded material, which is beneficial for visual monitoring during processing. Degassing considerably reduced the post-extrusion moisture content of Formula D3, which contains the highly hygroscopic polymer Kollidon® 17 PF, suggesting that the greatest influence of this process is on hygroscopic materials. The reduction in post-extrusion moisture content resulting from the inclusion of a degassing vent port, reduced fluctuations in the values of in-line monitoring parameters such as pressure and torque. Employing a degassing unit during hot-melt extrusion processing could help increase process efficacy and product quality.

  3. Bioethanol production from sweet potato using Saccharomyces diastaticus

    NASA Astrophysics Data System (ADS)

    Abdullah, Suryani, Irma; Pradia Paundradewa, J.

    2015-12-01

    Sweet potato contains about 16 to 40% dry matter and about 70-90% of the dry matter is a carbohydrate made up of starch, sugar, cellulose, hemicellulose and pectin so suitable for used as raw material for bioethanol. In this study focused on the manufacture of bioethanol with changes in temperature and concentration variations of yeast with sweet potato raw materials used yeast Saccharomyces diastaticus. Operating variables used are at a temperature of 30°C; 31,475°C; 35°C; 38,525°C; and 40°C with a yeast concentration of 25.9%; 30%; 40%; 50% and 54.1%. The experimental results obtained, the optimum conditions of ethanol fermentation with yeast Saccharomyces diastaticus on 36,67 °C temperature and yeast concentration of 43,43 % v / v.

  4. Micro and macroalgal biomass: a renewable source for bioethanol.

    PubMed

    John, Rojan P; Anisha, G S; Nampoothiri, K Madhavan; Pandey, Ashok

    2011-01-01

    Population outburst together with increased motorization has led to an overwhelming increase in the demand for fuel. In the milieu of economical and environmental concern, algae capable of accumulating high starch/cellulose can serve as an excellent alternative to food crops for bioethanol production, a green fuel for sustainable future. Certain species of algae can produce ethanol during dark-anaerobic fermentation and thus serve as a direct source for ethanol production. Of late, oleaginous microalgae generate high starch/cellulose biomass waste after oil extraction, which can be hydrolyzed to generate sugary syrup to be used as substrate for ethanol production. Macroalgae are also harnessed as renewable source of biomass intended for ethanol production. Currently there are very few studies on this issue, and intense research is required in future in this area for efficient utilization of algal biomass and their industrial wastes to produce environmentally friendly fuel bioethanol.

  5. LCA of bioethanol and furfural production from vetiver.

    PubMed

    Raman, Jegannathan Kenthorai; Gnansounou, Edgard

    2015-06-01

    In this study a prospective life cycle assessment of biorefinery system from vetiver leaves was carried out to know the environmental benefits of this system over conventional systems considering the geographical context of India. The composition of vetiver leaves from the experimental analysis revealed that vetiver is rich in cellulose (32.6%), hemicellulose (31.5%) and lignin (17.3%) that could be used as a feedstock for biorefinery. The comparative life cycle assessment results show that the carbon dioxide emission and fossil oil depletion could be reduced by 95% and 23% respectively in case of standalone bioethanol system, and 99% and 17% respectively in case of bioethanol and furfural system compared to that of conventional petrol and furfural systems. The sensitivity study indicates that the impact could be further reduced if vetiver biomass is used as a source of energy in biorefinery plant instead to the coal.

  6. Influences of smoking and caffeine consumption on trigeminal pain processing

    PubMed Central

    2014-01-01

    Background Many human and animal studies have shown the influence of nicotine and caffeine on pain perception and processing. This study aims to investigate whether smoking or caffeine consumption influences trigeminal pain processing. Methods Sixty healthy subjects were investigated using simultaneous recordings of the nociceptive blink reflex (nBR) and pain related evoked potentials (PREP) following nociceptive electrical stimulation on both sides of the forehead (V1). Thirty subjects were investigated before and after smoking a cigarette, as well as before and after taking a tablet of 400 mg caffeine. Results After smoking PREP showed decreased N2 and P2 latencies indicating central facilitation at supraspinal (thalamic or cortical) level. PREP amplitudes were not changed. NBR showed a decreased area under the curve (AUC) indicating central inhibition at brainstem level. After caffeine intake no significant changes were observed comparing nBR and PREP results before consumption. Conclusions Smoking influences trigeminal pain processing on supraspinal and brainstem level. In the investigated setting, caffeine consumption does not significantly alter trigeminal pain processing. This observation might help in the further understanding of the pathophysiology of pain disorders that are associated with excessive smoking habits such as cluster headache. Previous smoking has to be taken into account when performing electrophysiological studies to avoid bias of study results. PMID:24928141

  7. Influences of smoking and caffeine consumption on trigeminal pain processing.

    PubMed

    Holle, Dagny; Heber, Anke; Naegel, Steffen; Diener, Hans-Christoph; Katsarava, Zaza; Obermann, Mark

    2014-06-13

    Many human and animal studies have shown the influence of nicotine and caffeine on pain perception and processing. This study aims to investigate whether smoking or caffeine consumption influences trigeminal pain processing. Sixty healthy subjects were investigated using simultaneous recordings of the nociceptive blink reflex (nBR) and pain related evoked potentials (PREP) following nociceptive electrical stimulation on both sides of the forehead (V1). Thirty subjects were investigated before and after smoking a cigarette, as well as before and after taking a tablet of 400 mg caffeine. After smoking PREP showed decreased N2 and P2 latencies indicating central facilitation at supraspinal (thalamic or cortical) level. PREP amplitudes were not changed. NBR showed a decreased area under the curve (AUC) indicating central inhibition at brainstem level. After caffeine intake no significant changes were observed comparing nBR and PREP results before consumption. Smoking influences trigeminal pain processing on supraspinal and brainstem level. In the investigated setting, caffeine consumption does not significantly alter trigeminal pain processing. This observation might help in the further understanding of the pathophysiology of pain disorders that are associated with excessive smoking habits such as cluster headache. Previous smoking has to be taken into account when performing electrophysiological studies to avoid bias of study results.

  8. Rigid Facial Motion Influences Featural, But Not Holistic, Face Processing

    PubMed Central

    Xiao, Naiqi; Quinn, Paul C.; Ge, Liezhong; Lee, Kang

    2012-01-01

    We report three experiments in which we investigated the effect of rigid facial motion on face processing. Specifically, we used the face composite effect to examine whether rigid facial motion influences primarily featural or holistic processing of faces. In Experiments 1, 2, and 3, participants were first familiarized with dynamic displays in which a target face turned from one side to another; then at test, participants judged whether the top half of a composite face (the top half of the target face aligned or misaligned with the bottom half of a foil face) belonged to the target face. We compared performance in the dynamic condition to various static control conditions in Experiments 1, 2, and 3, which differed from each other in terms of the display order of the multiple static images or the inter stimulus interval (ISI) between the images. We found that the size of the face composite effect in the dynamic condition was significantly smaller than that in the static conditions. In other words, the dynamic face display influenced participants to process the target faces in a part-based manner and consequently their recognition of the upper portion of the composite face at test became less interfered with by the aligned lower part of the foil face. The findings from the present experiments provide the strongest evidence to date to suggest that the rigid facial motion mainly influences facial featural, but not holistic, processing. PMID:22342561

  9. Regional differences in rice hulls supply for bioethanol production.

    PubMed

    Imamoglu, Esra; Dalay, Meltem Conk; Sukan, Fazilet Vardar

    2013-12-01

    Agricultural by-products are becoming an attractive substrate for bioethanol production. The aim of this study was to evaluate the effects of regional differences in the rice hulls using Escherichia coli KO11 for bioethanol production. The rice hulls coded Edirne were obtained from Thrace Region, and the rice hulls coded Izmir were obtained from Aegean Region in Turkey. Rice hulls were treated by dilute acid before using them as substrates. The cells were incubated on an orbital shaker at 160 rpm under 30 °C during 96 h of the fermentation period. It was found that the maximum yield of ethanol from sugar (0.44 g ethanol/g reducing sugar) was obtained with the substrate C/N ratio of 29.16 in Izmir medium. The main difference was the dominant carbon source available as a substrate. It was detected that glucose concentration was about 2.5 times higher in Izmir medium, whereas xylose concentration was about two times higher in Edirne medium. The different results obtained with rice hulls from different origins could depend on the type of paddy as well as different cultivation conditions. These findings provide a valuable indicator for identifying suitable agricultural waste materials to be used as substrates for bioethanol production.

  10. Attainable region analysis for continuous production of second generation bioethanol

    PubMed Central

    2013-01-01

    Background Despite its semi-commercial status, ethanol production from lignocellulosics presents many complexities not yet fully solved. Since the pretreatment stage has been recognized as a complex and yield-determining step, it has been extensively studied. However, economic success of the production process also requires optimization of the biochemical conversion stage. This work addresses the search of bioreactor configurations with improved residence times for continuous enzymatic saccharification and fermentation operations. Instead of analyzing each possible configuration through simulation, we apply graphical methods to optimize the residence time of reactor networks composed of steady-state reactors. Although this can be easily made for processes described by a single kinetic expression, reactions under analysis do not exhibit this feature. Hence, the attainable region method, able to handle multiple species and its reactions, was applied for continuous reactors. Additionally, the effects of the sugars contained in the pretreatment liquor over the enzymatic hydrolysis and simultaneous saccharification and fermentation (SSF) were assessed. Results We obtained candidate attainable regions for separate enzymatic hydrolysis and fermentation (SHF) and SSF operations, both fed with pretreated corn stover. Results show that, despite the complexity of the reaction networks and underlying kinetics, the reactor networks that minimize the residence time can be constructed by using plug flow reactors and continuous stirred tank reactors. Regarding the effect of soluble solids in the feed stream to the reactor network, for SHF higher glucose concentration and yield are achieved for enzymatic hydrolysis with washed solids. Similarly, for SSF, higher yields and bioethanol titers are obtained using this substrate. Conclusions In this work, we demonstrated the capabilities of the attainable region analysis as a tool to assess the optimal reactor network with minimum

  11. Perspectives and new directions for the production of bioethanol using consolidated bioprocessing of lignocellulose.

    PubMed

    Xu, Qi; Singh, Arjun; Himmel, Michael E

    2009-06-01

    The U.S. DOE Energy Independence and Security Act (EISA) mandated attainment of a national production level of 36 billion gallons of biofuels (to be added to gasoline) by 2022, of which 21 billion gallons must be derived from renewable/sustainable feedstocks (e.g. lignocellulose). In order to attain these goals, the development of cost effective process technologies that can convert plant biomass to fermentable sugars must occur. An alternative route to production of bioethanol is the utilization of microorganisms that can both convert biomass to fermentable sugars and ferment the resultant sugars to ethanol in a process known as consolidated bioprocessing (CBP). Although various economic benefits and technology hurdles must be weighed in the course of choosing the CBP strategy to be pursued, we present arguments for developing the powerfully cellulolytic fungus, Trichoderma reesei, as an effective CBP microorganism.

  12. Identification of a laccase Glac15 from Ganoderma lucidum 77002 and its application in bioethanol production.

    PubMed

    Fang, Zemin; Liu, Xiaoman; Chen, Liyuan; Shen, Yu; Zhang, Xuecheng; Fang, Wei; Wang, Xiaotang; Bao, Xiaoming; Xiao, Yazhong

    2015-01-01

    Laccases have potential applications in detoxification of lignocellulosic biomass after thermochemical pretreatment and production of value-added products or biofuels from renewable biomass. However, their application in large-scale industrial and environmental processes has been severely thwarted by the high cost of commercial laccases. Therefore, it is necessary to identify new laccases with lower cost but higher activity to detoxify lignocellulosic hydrolysates and better efficiency to produce biofuels such as bioethanol. Laccases from Ganoderma lucidum represent proper candidates in processing of lignocellulosic biomass. G. lucidum 77002 produces three laccase isoenzymes with a total laccase activity of 141.1 U/mL within 6 days when using wheat bran and peanut powder as energy sources in liquid culture medium. A new isoenzyme named Glac15 was identified, purified, and characterized. Glac15 possesses an optimum pH of 4.5 to 5.0 and a temperature range of 45°C to 55°C for the substrates tested. It was stable at pH values ranging from 5.0 to 7.0 and temperatures lower than 55°C, with more than 80% activity retained after incubation for 2 h. When used in bioethanol production process, 0.05 U/mL Glac15 removed 84% of the phenolic compounds in prehydrolysate, and the yeast biomass reached 11.81 (optimal density at 600 nm (OD600)), compared to no growth in the untreated one. Addition of Glac15 before cellulase hydrolysis had no significant effect on glucose recovery. However, ethanol yield were improved in samples treated with laccases compared to that in control samples. The final ethanol concentration of 9.74, 10.05, 10.11, and 10.81 g/L were obtained from samples containing only solid content, solid content treated with Glac15, solid content containing 50% prehydrolysate, and solid content containing 50% prehydrolysate treated with Glac15, respectively. The G. lucidum laccase Glac15 has potentials in bioethanol production industry.

  13. Potential of bioethanol as a chemical building block for biorefineries: preliminary sustainability assessment of 12 bioethanol-based products.

    PubMed

    Posada, John A; Patel, Akshay D; Roes, Alexander; Blok, Kornelis; Faaij, André P C; Patel, Martin K

    2013-05-01

    The aim of this study is to present and apply a quick screening method and to identify the most promising bioethanol derivatives using an early-stage sustainability assessment method that compares a bioethanol-based conversion route to its respective petrochemical counterpart. The method combines, by means of a multi-criteria approach, quantitative and qualitative proxy indicators describing economic, environmental, health and safety and operational aspects. Of twelve derivatives considered, five were categorized as favorable (diethyl ether, 1,3-butadiene, ethyl acetate, propylene and ethylene), two as promising (acetaldehyde and ethylene oxide) and five as unfavorable derivatives (acetic acid, n-butanol, isobutylene, hydrogen and acetone) for an integrated biorefinery concept.

  14. Strategies for the production of high concentrations of bioethanol from seaweeds: production of high concentrations of bioethanol from seaweeds.

    PubMed

    Yanagisawa, Mitsunori; Kawai, Shigeyuki; Murata, Kousaku

    2013-01-01

    Bioethanol has attracted attention as an alternative to petroleum-derived fuel. Seaweeds have been proposed as some of the most promising raw materials for bioethanol production because they have several advantages over lignocellulosic biomass. However, because seaweeds contain low contents of glucans, i.e., polysaccharides composed of glucose, the conversion of only the glucans from seaweed is not sufficient to produce high concentrations of ethanol. Therefore, it is also necessary to produce ethanol from other specific carbohydrate components of seaweeds, including sulfated polysaccharides, mannitol, alginate, agar and carrageenan. This review summarizes the current state of research on the production of ethanol from seaweed carbohydrates for which the conversion of carbohydrates to sugars is a key step and makes comparisons with the production of ethanol from lignocellulosic biomass. This review provides valuable information necessary for the production of high concentrations of ethanol from seaweeds.

  15. Influences on particle shape in underwater pelletizing processes

    SciTech Connect

    Kast, O. E-mail: matthias.musialek@ikt.uni-stuttgart.de E-mail: christian.bonten@ikt.uni-stuttgart.de; Musialek, M. E-mail: matthias.musialek@ikt.uni-stuttgart.de E-mail: christian.bonten@ikt.uni-stuttgart.de; Geiger, K. E-mail: matthias.musialek@ikt.uni-stuttgart.de E-mail: christian.bonten@ikt.uni-stuttgart.de; Bonten, C. E-mail: matthias.musialek@ikt.uni-stuttgart.de E-mail: christian.bonten@ikt.uni-stuttgart.de

    2014-05-15

    Underwater pelletizing has gained high importance within the last years among the different pelletizing technologies, due to its advantages in terms of throughput, automation, pellet quality and applicability to a large variety of thermoplastics. The resulting shape and quality of pellets, however, differ widely, depending on material characteristics and effects not fully understood yet. In an experimental set-up, pellets of different volumes and shapes were produced and the medium pellet mass, the pellet surface and the bulk density were analyzed in order to identify the influence of material properties and process parameters. Additionally, the shaping kinetics at the die opening were watched with a specially developed camera system. It was found that rheological material properties correlate with process parameters and resulting particle form in a complex way. Higher cutting speeds were shown to have a deforming influence on the pellets, leading to less spherical s and lower bulk densities. More viscous materials, however, showed a better resistance against this. Generally, the viscous properties of polypropylene proofed to be dominant over the elastic ones in regard to their influence on pellet shape. It was also shown that the shapes filmed at the die opening and the actual form of the pellets after a cooling track do not always correlate, indicating a significant influence of thermodynamic properties during the cooling.

  16. The influence of cryogenic processes on the erosional Arctic shoreface

    USGS Publications Warehouse

    Are, F.; Reimnitz, E.; Grigoriev, M.; Hubberten, H.-W.; Rachold, V.

    2008-01-01

    Coastal dynamics and shoreface relief in ice-free seas are a function of hydrodynamic interactions between the sea and bottom sediments. In the Arctic, additional, cryogenic factors such as permafrost and the action of sea ice influence coastal processes. The goal of our paper is to assess this influence, mainly on the profile shape. Mathematical analyses of the shape of 63 shoreface profiles from the Laptev, Beaufort, and Chukchi Seas were carried out. The shapes of Arctic shoreface profiles and those of ice-free seas are compared. We found that large ice and silt content in perennially frozen sediments composing Arctic coasts favor their erosion. Sea ice plays an important role in sediment transport on the shoreface and correspondingly changes shoreface relief significantly. Some effects of ice intensify coastal erosion considerably, but others play a protective role. The overall influence of cryogenic processes on Arctic coasts composed of loose sediments is seen in that the average rate of coastal retreat is larger than in the temperate environments, even though Arctic coasts are protected by a continuous ice cover most of the year. The shape of the shoreface profile in the Arctic does not differ from that in ice-free seas, and is satisfactorily described by the Bruun/Dean equilibrium profile equation. The explanation of this fact is that all changes of the profile shape, caused by cryogenic processes, are short lived and quickly eliminated by wave action.

  17. Storm track processes and the opposing influences of climate change

    NASA Astrophysics Data System (ADS)

    Shaw, T. A.; Baldwin, M.; Barnes, E. A.; Caballero, R.; Garfinkel, C. I.; Hwang, Y.-T.; Li, C.; O'Gorman, P. A.; Rivière, G.; Simpson, I. R.; Voigt, A.

    2016-09-01

    Extratropical cyclones are storm systems that are observed to travel preferentially within confined regions known as storm tracks. They contribute to precipitation, wind and temperature extremes in mid-latitudes. Cyclones tend to form where surface temperature gradients are large, and the jet stream influences their speed and direction of travel. Storm tracks shape the global climate through transport of energy and momentum. The intensity and location of storm tracks varies seasonally, and in response to other natural variations, such as changes in tropical sea surface temperature. A hierarchy of numerical models of the atmosphere-ocean system -- from highly idealized to comprehensive -- has been used to study and predict responses of storm tracks to anthropogenic climate change. The future position and intensity of storm tracks depend on processes that alter temperature gradients. However, different processes can have opposing influences on temperature gradients, which leads to a tug of war on storm track responses and makes future projections more difficult. For example, as climate warms, surface shortwave cloud radiative changes increase the Equator-to-pole temperature gradient, but at the same time, longwave cloud radiative changes reduce this gradient. Future progress depends on understanding and accurately quantifying the relative influence of such processes on the storm tracks.

  18. Fairness influences early signatures of reward-related neural processing.

    PubMed

    Massi, Bart; Luhmann, Christian C

    2015-12-01

    Many humans exhibit a strong preference for fairness during decision-making. Although there is evidence that social factors influence reward-related and affective neural processing, it is unclear if this effect is mediated by compulsory outcome evaluation processes or results from slower deliberate cognition. Here we show that the feedback-related negativity (FRN) and late positive potential (LPP), two signatures of early hedonic processing, are modulated by the fairness of rewards during a passive rating task. We find that unfair payouts elicit larger FRNs than fair payouts, whereas fair payouts elicit larger LPPs than unfair payouts. This is true both in the time-domain, where the FRN and LPP are related, and in the time-frequency domain, where the two signals are largely independent. Ultimately, this work demonstrates that fairness affects the early stages of reward and affective processing, suggesting a common biological mechanism for social and personal reward evaluation.

  19. Influence of the element silicon on laser processing

    NASA Astrophysics Data System (ADS)

    Yan, Qi

    2005-01-01

    Laser cutting had been widely used in the material processing field with the increase of the requirements on the quality and work efficiency. As to the laser cutting, there had many factors that could affect the quality of cuts. Among them, the chemical composition played an important role because laser processing was a kind of interaction among laser beam, shielding gas and materials. Compared with the other element, silicon element had a deleterious effect on the laser processing which resulted in cuts with a dross and brittleness in the welded seam. However, many kinds of steel with high amount of silicon need to be processed by laser technology in recent years. In this paper, the influence of silicon element on the quality of laser cutting and laser welding was discussed. Continuous CO2 laser was used to cut and weld materials with different amount of silicon. Results showed that with the increase amount of silicon, the speed of laser cutting and laser welding decreased in order to obtain the good cuts and welds. Silicon had the obvious influence on the laser processing technology and quality. Microstructure of the laser welds for materials with high amount of silicon was also analyzed in this paper.

  20. Influences of Multisensory Experience on Subsequent Unisensory Processing

    PubMed Central

    Shams, Ladan; Wozny, David R.; Kim, Robyn; Seitz, Aaron

    2011-01-01

    Multisensory perception has been the focus of intense investigation in recent years. It is now well-established that crossmodal interactions are ubiquitous in perceptual processing and endow the system with improved precision, accuracy, processing speed, etc. While these findings have shed much light on principles and mechanisms of perception, ultimately it is not very surprising that multiple sources of information provides benefits in performance compared to a single source of information. Here, we argue that the more surprising recent findings are those showing that multisensory experience also influences the subsequent unisensory processing. For example, exposure to auditory–visual stimuli can change the way that auditory or visual stimuli are processed subsequently even in isolation. We review three sets of findings that represent three different types of learning ranging from perceptual learning, to sensory recalibration, to associative learning. In all these cases exposure to multisensory stimuli profoundly influences the subsequent unisensory processing. This diversity of phenomena may suggest that continuous modification of unisensory representations by multisensory relationships may be a general learning strategy employed by the brain. PMID:22028697

  1. Build Your Own Second-Generation Bioethanol Plant in the Classroom!

    ERIC Educational Resources Information Center

    van Seters, Janneke R.; Sijbers, Jeroen P. J.; Denis, Misha; Tramper, Johannes

    2011-01-01

    The production of bioethanol from cellulosic waste is described. The experiment is suitable for students in secondary school classroom settings and leads to bioethanol in a concentration high enough to burn the liquid. The experiment consists of three steps: (i) the cellulose of the waste material is converted to glucose by cellulase enzymes, (ii)…

  2. Certified reference material of bioethanol for metrological traceability in electrochemical parameters analyses.

    PubMed

    Serta Fraga, Isabel Cristina; Ribeiro, Carla Matos; Sobral, Sidney Pereira; Dias, Júlio Cesar; Gonçalves, Mary Ane; Borges, Paulo Paschoal; Gonzaga, Fabiano Barbieri

    2012-09-15

    Bioethanol has become an important biofuel because it is a source of renewable energy and can help to decrease global warming. However, the quality of bioethanol needs to be guaranteed so that it can be trusted and accepted in international trade. The Brazilian Metrology Institute (Inmetro) has been developing a certified reference material (CRM) for bioethanol to ensure quality control for measurement in the bioethanol matrix. Inmetro has certified 11 quality parameters. Using these, the CRM of bioethanol will contribute to guaranteeing metrological traceability and reliable measurement results. These factors can be used to compare different bioethanols produced to comply with legislation in different countries in order to avoid technical barriers and thus increase the international trade in Brazilian bioethanol. The aim of this paper is to present the results of certification studies using three important electrochemical quality parameters in the CRM of bioethanol-total acid number, pHe and electrolytic conductivity-which are crucial in protecting the metallic parts of a vehicle from corrosion. The certified results obtained for total acid number, pHe and electrolytic conductivity parameters were (16.2±1.7)mg L(-1), 6.07±0.30, and (1.03±0.11)μS cm(-1), respectively. The uncertainties for all parameters were the expanded uncertainty obtained by multiplying the combined standard uncertainty by a coverage factor of k=2, which represents an approximately 95% confidence level.

  3. Phenotypic evaluation of natural and industrial Saccharomyces yeasts for different traits desirable in industrial bioethanol production.

    PubMed

    Mukherjee, Vaskar; Steensels, Jan; Lievens, Bart; Van de Voorde, Ilse; Verplaetse, Alex; Aerts, Guido; Willems, Kris A; Thevelein, Johan M; Verstrepen, Kevin J; Ruyters, Stefan

    2014-11-01

    Saccharomyces cerevisiae is the organism of choice for many food and beverage fermentations because it thrives in high-sugar and high-ethanol conditions. However, the conditions encountered in bioethanol fermentation pose specific challenges, including extremely high sugar and ethanol concentrations, high temperature, and the presence of specific toxic compounds. It is generally considered that exploring the natural biodiversity of Saccharomyces strains may be an interesting route to find superior bioethanol strains and may also improve our understanding of the challenges faced by yeast cells during bioethanol fermentation. In this study, we phenotypically evaluated a large collection of diverse Saccharomyces strains on six selective traits relevant for bioethanol production with increasing stress intensity. Our results demonstrate a remarkably large phenotypic diversity among different Saccharomyces species and among S. cerevisiae strains from different origins. Currently applied bioethanol strains showed a high tolerance to many of these relevant traits, but several other natural and industrial S. cerevisiae strains outcompeted the bioethanol strains for specific traits. These multitolerant strains performed well in fermentation experiments mimicking industrial bioethanol production. Together, our results illustrate the potential of phenotyping the natural biodiversity of yeasts to find superior industrial strains that may be used in bioethanol production or can be used as a basis for further strain improvement through genetic engineering, experimental evolution, or breeding. Additionally, our study provides a basis for new insights into the relationships between tolerance to different stressors.

  4. Build Your Own Second-Generation Bioethanol Plant in the Classroom!

    ERIC Educational Resources Information Center

    van Seters, Janneke R.; Sijbers, Jeroen P. J.; Denis, Misha; Tramper, Johannes

    2011-01-01

    The production of bioethanol from cellulosic waste is described. The experiment is suitable for students in secondary school classroom settings and leads to bioethanol in a concentration high enough to burn the liquid. The experiment consists of three steps: (i) the cellulose of the waste material is converted to glucose by cellulase enzymes, (ii)…

  5. Study of user influence in routine SPM data processing

    NASA Astrophysics Data System (ADS)

    Nečas, D.; Klapetek, P.

    2017-03-01

    The quantitative results obtained using scanning probe microscopy (SPM) are influenced not only by instrumentation factors, but also by humans—the SPM users that perform the data processing and the evaluation of statistical characteristics, dimensions and other parameters from the images. We investigate this user influence empirically by performing several experiments in which real humans process SPM data in different settings using the same software, and statistically characterise the results. Two types of experiments are conducted: one in a well-defined laboratory setting where prescribed procedures requiring user input are applied by experienced users to large ensembles of similar data; the other in an open setting in which a large group of SPM users evaluate the same images to obtain specified parameters but without external guidance. The open study in particular brings about results that should be alarming for the SPM community and SPM metrology in particular. We also attempt to derive some guidance for the design of SPM data processing software functions from the results and classify the amount of user input in the data processing functions.

  6. Face Context Influences Local Part Processing: An ERP Study.

    PubMed

    Zhang, Hong; Sun, Yaoru; Zhao, Lun

    2017-01-01

    Perception of face parts on the basis of features is thought to be different from perception of whole faces, which is more based on configural information. Face context is also suggested to play an important role in face processing. To investigate how face context influences the early-stage perception of facial local parts, we used an oddball paradigm that tested perceptual stages of face processing rather than recognition. We recorded the event-related potentials (ERPs) elicited by whole faces and face parts presented in four conditions (upright-normal, upright-thatcherised, inverted-normal and inverted-thatcherised), as well as the ERPs elicited by non-face objects (whole houses and house parts) with corresponding conditions. The results showed that face context significantly affected the N170 with increased amplitudes and earlier peak latency for upright normal faces. Removing face context delayed the P1 latency but did not affect the P1 amplitude prominently for both upright and inverted normal faces. Across all conditions, neither the N170 nor the P1 was modulated by house context. The significant changes on the N170 and P1 components revealed that face context influences local part processing at the early stage of face processing and this context effect might be specific for face perception. We further suggested that perceptions of whole faces and face parts are functionally distinguished.

  7. Motor force field learning influences visual processing of target motion.

    PubMed

    Brown, Liana E; Wilson, Elizabeth T; Goodale, Melvyn A; Gribble, Paul L

    2007-09-12

    There are reciprocal connections between visual and motor areas of the cerebral cortex. Although recent studies have provided intriguing new insights, in comparison with volume of research on the visual control of movement, relatively little is known about how movement influences vision. The motor system is perfectly suited to learn about environmental forces. Does environmental force information, learned by the motor system, influence visual processing? Here, we show that learning to compensate for a force applied to the hand influenced how participants predicted target motion for interception. Ss trained in one of three constant force fields by making reaching movements while holding a robotic manipulandum. The robot applied forces in a null [null force field (NFF)], leftward [leftward force field (LFF)], or [rightward force field (RFF)] direction. Training was followed immediately with an interception task. The target accelerated from left to right and Ss's task was to stab it. When viewing time was optimal for prediction, the RFF group initiated their responses earlier and hit more targets, and the LFF group initiated their responses later and hit fewer targets, than the NFF group. In follow-up experiments, we show that motor learning is necessary, and we rule out the possibility that explicit force direction information drives how Ss altered their predictions of visual motion. Environmental force information, acquired by motor learning, influenced how the motion of nearby visual targets was predicted.

  8. Evaluation of bioactive components and antioxidant and anticancer properties of citrus wastes generated during bioethanol production.

    PubMed

    Im, Soon Jae; Kim, Jae-Hoon; Kim, Min Young

    2014-04-01

    In the bioethanol production process employing citrus peels, a large amount of enzymatic hydrolyzed residues is generated as waste material. The bioactive compounds, and antioxidant and anticancer activities of these residues were investigated in the present study. Hydrolyzed citrus residues exhibited similar antioxidant activity as the unhydrolyzed control, which was positively correlated to the contents of total phenols, flavonoids and total carotenoid. Some flavonoids (naringin, naringenin, hesperetin and neohesperidin) and two high value co-products (D-limonene and galacturonic acid) were detected only in hydrolyzed residues. In addition, hydrolyzed residues showed antiproliferative activity and sub-G1 arrest in human melanoma A375 and colon cancer HCT116 cells. These results provide an alternative use for hydrolyzed citrus residues in the functional food, cosmetic and pharmaceutical industries.

  9. A novel sono-assisted acid pretreatment of chili post harvest residue for bioethanol production.

    PubMed

    Sindhu, Raveendran; Binod, Parameswaran; Pandey, Ashok

    2016-08-01

    The objective of the present study was to develop a sono-assisted acid pretreatment strategy for the effective removal of lignin and hemicelluloses and to improve the sugar yield from chili post harvest residue. Operational parameters that affect the pretreatment efficiency were studied and optimized. Inhibitor analysis of the hydrolyzate revealed that major fermentation inhibitors like furfural, hydroxymethyl furfural and organic acids like citric acid, succinic acid and propionic acid were absent. Changes in structural properties of the biomass were studied in relation to the pretreatment process using scanning electron microscopy (SEM), X-ray diffraction (XRD) and Fourier Transform Infrared (FTIR) analysis, and the changes in chemical composition was also monitored. The biomass pretreated with the optimized novel method yielded 0.465g/g of reducing sugars on enzymatic hydrolysis. Fermentation of the non-detoxified hydrolysate yielded 2.14% of bioethanol with a fermentation efficiency of 71.03%.

  10. Potential of Brachiaria mutica (Para grass) for bioethanol production from Loktak Lake.

    PubMed

    Sahoo, Dinabandhu; Ummalyma, Sabeela Beevi; Okram, Aswini Kumar; Sukumaran, Rajeev K; George, Emrin; Pandey, Ashok

    2017-10-01

    The aim of present study was to evaluate feasibility of using the Para grass as feedstock for production of bioethanol. Process involved the pretreatment with dilute acid or alkali and followed by enzymatic saccharification with commercial cellulase. Maximum sugar release of 696mg/g was obtained from 10% biomass loading and 0.5% w/v of alkali whereas in the case of acid pretreatment maximum sugar of 660mg/g was obtained from 20% biomass loading and 2% w/v acid loading. Results showed that Para grass utilization as a biorefinery feedstock can be a potential strategy to address the sustainable utilization of this invasive grass thereby keeping its population in check in the Loktak Lake. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. Geologic processes influence the effects of mining on aquatic ecosystems

    USGS Publications Warehouse

    Schmidt, Travis S.; Clements, William H.; Wanty, Richard B.; Verplanck, Philip L.; Church, Stanley E.; San Juan, Carma A.; Fey, David L.; Rockwell, Barnaby W.; DeWitt, Ed H.; Klein, Terry L.

    2012-01-01

    Geologic processes strongly influence water and sediment quality in aquatic ecosystems but rarely are geologic principles incorporated into routine biomonitoring studies. We test if elevated concentrations of metals in water and sediment are restricted to streams downstream of mines or areas that may discharge mine wastes. We surveyed 198 catchments classified as “historically mined” or “unmined,” and based on mineral-deposit criteria, to determine whether water and sediment quality were influenced by naturally occurring mineralized rock, by historical mining, or by a combination of both. By accounting for different geologic sources of metals to the environment, we were able to distinguish aquatic ecosystems limited by metals derived from natural processes from those due to mining. Elevated concentrations of metals in water and sediment were not restricted to mined catchments; depauperate aquatic communities were found in unmined catchments. The type and intensity of hydrothermal alteration and the mineral deposit type were important determinants of water and sediment quality as well as the aquatic community in both mined and unmined catchments. This study distinguished the effects of different rock types and geologic sources of metals on ecosystems by incorporating basic geologic processes into reference and baseline site selection, resulting in a refined assessment. Our results indicate that biomonitoring studies should account for natural sources of metals in some geologic environments as contributors to the effect of mines on aquatic ecosystems, recognizing that in mining-impacted drainages there may have been high pre-mining background metal concentrations.

  12. Geologic processes influence the effects of mining on aquatic ecosystems.

    PubMed

    Schmidt, Travis S; Clements, William H; Wanty, Richard B; Verplanck, Philip L; Church, Stanley E; San Juan, Carma A; Fey, David L; Rockwell, Barnaby W; DeWitt, Ed H; Klein, Terry L

    2012-04-01

    Geologic processes strongly influence water and sediment quality in aquatic ecosystems but rarely are geologic principles incorporated into routine biomonitoring studies. We test if elevated concentrations of metals in water and sediment are restricted to streams downstream of mines or areas that may discharge mine wastes. We surveyed 198 catchments classified as "historically mined" or "unmined," and based on mineral-deposit criteria, to determine whether water and sediment quality were influenced by naturally occurring mineralized rock, by historical mining, or by a combination of both. By accounting for different geologic sources of metals to the environment, we were able to distinguish aquatic ecosystems limited by metals derived from natural processes from those due to mining. Elevated concentrations of metals in water and sediment were not restricted to mined catchments; depauperate aquatic communities were found in unmined catchments. The type and intensity of hydrothermal alteration and the mineral deposit type were important determinants of water and sediment quality as well as the aquatic community in both mined and unmined catchments. This study distinguished the effects of different rock types and geologic sources of metals on ecosystems by incorporating basic geologic processes into reference and baseline site selection, resulting in a refined assessment. Our results indicate that biomonitoring studies should account for natural sources of metals in some geologic environments as contributors to the effect of mines on aquatic ecosystems, recognizing that in mining-impacted drainages there may have been high pre-mining background metal concentrations.

  13. Simultaneous saccharification and continuous fermentation of sludge-containing mash for bioethanol production by Saccharomyces cerevisiae CHFY0321.

    PubMed

    Moon, Se-Kwon; Kim, Seung Wook; Choi, Gi-Wook

    2012-02-20

    A continuous process was employed to improve the volumetric productivity of bioethanol production from cassava mash containing sludge and to simplify the process of ethanol production from cassava. After raw cassava powder was liquefied, it was used directly in a continuous process without sludge filtration or saccharification. A fermentor consisting of four linked stirrer tanks was used for simultaneous saccharification and continuous fermentation (SSCF). Although the mash contained sludge, continuous fermentation was successfully achieved. We chose the dilution rate on the basis of the maximum saccharification time; the highest volumetric productivity and ethanol yield were observed at a dilution rate of 0.028 h⁻¹. The volumetric productivity, final ethanol concentration, and % of theoretical ethanol yield were 2.41 g/Lh, 86.1g/L, and 91%, respectively. This SSCF process using the self-flocculating yeast Saccharomyces cerevisiae CHFY0321 illustrates the possibility of realizing cost-effective bioethanol production by eliminating additional saccharification and filtration processes. In addition, flocculent CHFY0321, which our group developed, showed excellent fermentation results under continuous ethanol production.

  14. Psychoneuroendocrine processes in human pregnancy influence fetal development and health.

    PubMed

    Wadhwa, Pathik D

    2005-09-01

    Individual differences in psychoneuroendocrine function play an important role in health and disease. Developmental models postulate that these individual differences evolve through a progressive series of dynamic time-, place- and context-dependent interactions between genes and environments in fetal, infant and adult life. The effects of early experience have longer-lasting and more permanent consequences than those later in life. Experimental studies in animals have provided convincing evidence to support a causal role for stress-related psychoneuroendocrine processes in negatively influencing critical developmental and health outcomes over the life span, and have also offered valuable insights into putative physiological mechanisms. However, the generalizability of these findings from animals to humans may be limited by the existence of large inter-species differences in physiology and the developmental time-line. We have initiated a program of research in behavioral perinatology and conducted studies over the past several years to examine the effects of stress-related psychoneuroendocrine processes in human pregnancy on fetal developmental and health outcomes. Our findings support a significant and independent role for maternal prenatal stress in the etiology of prematurity-related outcomes, and suggest that these effects are mediated, in part, by the maternal-placental-fetal neuroendocrine axis, and specifically by placental corticotropin-releasing hormone. Our findings also suggest that the use of a fetal challenge paradigm offers a novel way to quantify fetal neurobehavioral maturity in utero, and that the maternal environment exerts a significant influence on the fetal neurodevelopmental processes related to recognition, memory and habituation. Finally, our findings provide preliminary evidence to support the notion that the influence of prenatal stress and maternal-placental hormones on the developing fetus may persist after birth, as assessed by measures

  15. The Influence of Various Factors on the Methane Fermentation Process

    NASA Astrophysics Data System (ADS)

    Kurbanova, M. G.; Egushova, E. A.; Pozdnjakova, OG

    2015-09-01

    The article describes the stages of the methane fermentation process. The phases of methane formation are characterized. The results of the experimental data based on the study of various factors influencing the rate of biogas production and its yield are presented. Such factors as the size of the substrate particles and temperature conditions in the reactor are considered. It is revealed on the basis of experimental data which of the farm animals and poultry excrements are exposed to the most complete fermentation without special preparation. The relationship between fermentation regime, particle size of the feedstock and biogas yield is graphically presented.

  16. EMERGING TECHNOLOGIES FOR BIOETHANOL RECOVERY USING MEMBRANE PROCESSES

    EPA Science Inventory

    Petroleum is currently used as the starting material for many commodity chemicals and fuels, but the prospect of dwindling oil supplies, reliance on unpredictable oil sources, and the carbon balance of the planet are concerns. Sustainable production of commodity chemicals and bi...

  17. EMERGING TECHNOLOGIES FOR BIOETHANOL RECOVERY USING MEMBRANE PROCESSES

    EPA Science Inventory

    Petroleum is currently used as the starting material for many commodity chemicals and fuels, but the prospect of dwindling oil supplies, reliance on unpredictable oil sources, and the carbon balance of the planet are concerns. Sustainable production of commodity chemicals and bi...

  18. Potential of the waste from beer fermentation broth for bio-ethanol production without any additional enzyme, microbial cells and carbohydrates.

    PubMed

    Ha, Jung Hwan; Shah, Nasrullah; Ul-Islam, Mazhar; Park, Joong Kon

    2011-08-10

    The potential of the waste from beer fermentation broth (WBFB) for the production of bio-ethanol using a simultaneous saccharification and fermentation process without any extra additions of saccharification enzymes, microbial cells or carbohydrate was tested. The major microbial cells in WBFB were isolated and identified. The variations in compositions of WBFB with stock time were investigated. There was residual activity of starch hydrolyzing enzymes in WBFB. The effects of reaction modes e.g. static and shaking on bio-ethanol production were studied. After 7 days of cultivation using the supernatant of WBFB at 30 °C the ethanol concentration reached 103.8 g/L in shaking culture and 91.5 g/L in static culture. Agitation experiments conducted at a temperature-profile process in which temperature was increased from 25 to 67 °C shortened the simultaneous process time. The original WBFB was more useful than the supernatant of WBFB in getting the higher concentration of ethanol and reducing the fermentation time. From this whole study it was found that WBFB is a cheap and suitable source for bio-ethanol production. Copyright © 2011 Elsevier Inc. All rights reserved.

  19. Influence of Digital Camera Errors on the Photogrammetric Image Processing

    NASA Astrophysics Data System (ADS)

    Sužiedelytė-Visockienė, Jūratė; Bručas, Domantas

    2009-01-01

    The paper deals with the calibration of digital camera Canon EOS 350D, often used for the photogrammetric 3D digitalisation and measurements of industrial and construction site objects. During the calibration data on the optical and electronic parameters, influencing the distortion of images, such as correction of the principal point, focal length of the objective, radial symmetrical and non-symmetrical distortions were obtained. The calibration was performed by means of the Tcc software implementing the polynomial of Chebichev and using a special test-field with the marks, coordinates of which are precisely known. The main task of the research - to determine how parameters of the camera calibration influence the processing of images, i. e. the creation of geometric model, the results of triangulation calculations and stereo-digitalisation. Two photogrammetric projects were created for this task. In first project the non-corrected and in the second the corrected ones, considering the optical errors of the camera obtained during the calibration, images were used. The results of analysis of the images processing is shown in the images and tables. The conclusions are given.

  20. Influence of atomic processes on the implosion of plasma liners

    SciTech Connect

    Kim, Hyoungkeun; Zhang Lina; Samulyak, Roman; Parks, Paul

    2012-08-15

    The influence of atomic physics processes on the implosion of plasma liners for magneto-inertial nuclear fusion has been investigated numerically by using the method of front tracking in spherically symmetric geometry and equation of state models accounting for dissociation and ionization. Simulation studies of the self-collapse of argon liners to be used in the Los Alamos Plasma Liner Experiment (PLX) program have been performed as well as studies of implosion of deuterium and argon liners on plasma targets. Results show that atomic processes in converging liners reduce the temperature of liners and increase the Mach number that results in the increase of the stagnation pressure and the fusion energy gain. For deuterium and argon liners imploding on plasma targets, dissociation and ionization increased the stagnation pressure and the fusion energy gain by the factor of 1.5 (deuterium) and 2 (argon) correspondingly. Similarly, ionization during the self-collapse of argon liners leads to approximately doubling of the Mach number and the stagnation pressure. The influence of the longitudinal density spread of the liner has also been investigated. The self-collapse stagnation pressure decreased by the factor of 8.7 when the initial position of the liner was shifted from the merging radius (33 cm) to the PLX chamber edge (137.2 cm). Simulations with and without the heat conduction demonstrated that the heat conduction has negligible effect on the self-collapse pressure of argon liners.

  1. Potential environmental impact of bioethanol production chain from fiber sorghum to be used in passenger cars.

    PubMed

    Forte, Annachiara; Zucaro, Amalia; Fagnano, Massimo; Fierro, Angelo

    2017-11-15

    A life cycle assessment (LCA) was applied to assess the environmental load of a prospective local bioethanol (EtOH) production system in Southern Italy by using lignocellulosic Fiber sorghum (FS) feedstock. A two steps analysis was carried out considering: (i) a "cradle-to-farm gate" LCA to investigate thoroughly the FS cultivation on hilly marginal land and (ii) a "cradle-to-wheels" system boundary encompassing the environmental pressure of the whole EtOH supply-use chain. Primary data related to lignocellulosic biomass production were combined with experimental feedstock conversion processes through advanced second generation technology. The purpose was the evaluation of the environmental performance of different EtOH-gasoline mixtures in midsize passenger cars: E10 (10% of EtOH and 90% of gasoline) and E85 (85% of EtOH and 15% of gasoline). N fertilization appeared as the prevailing contributor of the crop phase. The "cradle-to-wheels" results concerning E10 passenger car disclosed that the main hotspots were represented by the input of low sulphur petrol (66%) and the linked tailpipe emissions (15%), for almost all the impact categories. Otherwise, for E85 flex-fuel vehicle, the major drivers were represented by the feedstock production (46%) and the imported electricity used in the conversion facility (18%). The FS EtOH blends entailed potential environmental benefits compared with the fossil counterpart (gasoline) for climate change, ozone and fossil depletions. Otherwise, they evidenced a worse profile in terms of acidification, eutrophication and particulate matter formation. Within the context of a the prospective territorial bio-refinery network, the comparison of the annual FS bioethanol based systems with similar EtOH scenarios from giant reed perennial crops highlighted: (i) the importance to optimize the N-management for FS feedstock cultivation and (ii) the need to increase the use of the renewable energy carriers along the industrial conversion

  2. The influence of stress on fear memory processes.

    PubMed

    Martijena, I D; Molina, V A

    2012-04-01

    It is well recognized that stressful experiences promote robust emotional memories, which are well remembered. The amygdaloid complex, principally the basolateral complex (BLA), plays a pivotal role in fear memory and in the modulation of stress-induced emotional responses. A large number of reports have revealed that GABAergic interneurons provide a powerful inhibitory control of the activity of projecting glutamatergic neurons in the BLA. Indeed, a reduced GABAergic control in the BLA is essential for the stress-induced influence on the emergence of associative fear memory and on the generation of long-term potentiation (LTP) in BLA neurons. The extracellular signal-regulated kinase (ERK) subfamily of the mitogen-activated protein kinase (MAPK) signaling pathway in the BLA plays a central role in the consolidation process and synaptic plasticity. In support of the view that stress facilitates long-term fear memory, stressed animals exhibited a phospho-ERK2 (pERK2) increase in the BLA, suggesting the involvement of this mechanism in the promoting influence of threatening stimuli on the consolidation fear memory. Moreover, the occurrence of reactivation-induced lability is prevented when fear memory is encoded under intense stressful conditions since the memory trace remains immune to disruption after recall in previously stressed animals. Thus, the underlying mechanism in retrieval-induced instability seems not to be functional in memories formed under stress. All these findings are indicative that stress influences both the consolidation and reconsolidation fear memory processes. Thus, it seems reasonable to propose that the emotional state generated by an environmental challenge critically modulates the formation and maintenance of long-term fear memory.

  3. Environmental impacts of producing bioethanol and biobased lactic acid from standalone and integrated biorefineries using a consequential and an attributional life cycle assessment approach.

    PubMed

    Parajuli, Ranjan; Knudsen, Marie Trydeman; Birkved, Morten; Djomo, Sylvestre Njakou; Corona, Andrea; Dalgaard, Tommy

    2017-11-15

    This study evaluates the environmental impacts of biorefinery products using consequential (CLCA) and attributional (ALCA) life cycle assessment (LCA) approaches. Within ALCA, economic allocation method was used to distribute impacts among the main products and the coproducts, whereas within the CLCA system expansion was adopted to avoid allocation. The study seeks to answer the questions (i) what is the environmental impacts of process integration?, and (ii) do CLCA and ALCA lead to different conclusions when applied to biorefinery?. Three biorefinery systems were evaluated and compared: a standalone system producing bioethanol from winter wheat-straw (system A), a standalone system producing biobased lactic acid from alfalfa (system B), and an integrated biorefinery system (system C) combining the two standalone systems and producing both bioethanol and lactic acid. The synergy of the integration was the exchange of useful energy necessary for biomass processing in the two standalone systems. The systems were compared against a common reference flow: "1MJEtOH+1kgLA", which was set on the basis of products delivered by the system C. Function of the reference flow was to provide service of both fuel (bioethanol) at 99.9% concentration (wt. basis) and biochemical (biobased lactic acid) in food industries at 90% purity; both products delivered at biorefinery gate. The environmental impacts of interest were global warming potential (GWP100), eutrophication potential (EP), non-renewable energy (NRE) use and the agricultural land occupation (ALO). Regardless of the LCA approach adopted, system C performed better in most of the impact categories than both standalone systems. The process wise contribution to the obtained environmental impacts also showed similar impact pattern in both approaches. The study also highlighted that the recirculation of intermediate materials, e.g. C5 sugar to boost bioethanol yield and that the use of residual streams in the energy conversion

  4. Potential CO2 emission reduction by development of non-grain-based bioethanol in China.

    PubMed

    Li, Hongqiang; Wang, Limao; Shen, Lei

    2010-10-01

    Assessment of the potential CO(2) emission reduction by development of non-grain-based ethanol in China is valuable for both setting up countermeasures against climate change and formulating bioethanol policies. Based on the land occupation property, feedstock classification and selection are conducted, identifying sweet sorghum, cassava, and sweet potato as plantation feedstocks cultivated from low-quality arable marginal land resources and molasses and agricultural straws as nonplantation feedstocks derived from agricultural by-products. The feedstock utilization degree, CO(2) reduction coefficient of bioethanol, and assessment model of CO(2) emission reduction potential of bioethanol are proposed and established to assess the potential CO(2) emission reduction by development of non-grain-based bioethanol. The results show that China can obtain emission reduction potentials of 10.947 and 49.027 Mt CO(2) with non-grain-based bioethanol in 2015 and 2030, which are much higher than the present capacity, calculated as 1.95 Mt. It is found that nonplantation feedstock can produce more bioethanol so as to obtain a higher potential than plantation feedstock in both 2015 and 2030. Another finding is that developing non-grain-based bioethanol can make only a limited contribution to China's greenhouse gas emission reduction. Moreover, this study reveals that the regions with low and very low potentials for emission reduction will dominate the spatial distribution in 2015, and regions with high and very high potentials will be the majority in 2030.

  5. Potential CO2 Emission Reduction by Development of Non-Grain-Based Bioethanol in China

    NASA Astrophysics Data System (ADS)

    Li, Hongqiang; Wang, Limao; Shen, Lei

    2010-10-01

    Assessment of the potential CO2 emission reduction by development of non-grain-based ethanol in China is valuable for both setting up countermeasures against climate change and formulating bioethanol policies. Based on the land occupation property, feedstock classification and selection are conducted, identifying sweet sorghum, cassava, and sweet potato as plantation feedstocks cultivated from low-quality arable marginal land resources and molasses and agricultural straws as nonplantation feedstocks derived from agricultural by-products. The feedstock utilization degree, CO2 reduction coefficient of bioethanol, and assessment model of CO2 emission reduction potential of bioethanol are proposed and established to assess the potential CO2 emission reduction by development of non-grain-based bioethanol. The results show that China can obtain emission reduction potentials of 10.947 and 49.027 Mt CO2 with non-grain-based bioethanol in 2015 and 2030, which are much higher than the present capacity, calculated as 1.95 Mt. It is found that nonplantation feedstock can produce more bioethanol so as to obtain a higher potential than plantation feedstock in both 2015 and 2030. Another finding is that developing non-grain-based bioethanol can make only a limited contribution to China’s greenhouse gas emission reduction. Moreover, this study reveals that the regions with low and very low potentials for emission reduction will dominate the spatial distribution in 2015, and regions with high and very high potentials will be the majority in 2030.

  6. Influence of different natural physical fields on biological processes.

    PubMed

    Mashinsky, A L

    2001-01-01

    In space flight conditions gravity, magnetic, and electrical fields as well as ionizing radiation change both in size, and in direction. This causes disruptions in the conduct of some physical processes, chemical reactions, and metabolism in living organisms. In these conditions organisms of different phylogenetic level change their metabolic reactions undergo changes such as disturbances in ionic exchange both in lower and in higher plants, changes in cell morphology for example, gyrosity in Proteus (Proteus vulgaris), spatial disorientation in coleoptiles of Wheat (Triticum aestivum) and Pea (Pisum sativum) seedlings, mutational changes in Crepis (Crepis capillaris) and Arabidopsis (Arabidopsis thaliana) seedling. It has been found that even in the absence of gravity, gravireceptors determining spatial orientation in higher plants under terrestrial conditions are formed in the course of ontogenesis. Under weightlessness this system does not function and spatial orientation is determined by the light flux gradient or by the action of some other factors. Peculiarities of the formation of the gravireceptor apparatus in higher plants, amphibians, fish, and birds under space flight conditions have been observed. It has been found that the system in which responses were accompanied by phase transition have proven to be gravity-sensitive under microgravity conditions. Such reactions include also the process of photosynthesis which is the main energy production process in plants. In view of the established effects of microgravity and different natural physical fields on biological processes, it has been shown that these processes change due to the absence of initially rigid determination. The established biological effect of physical fields influence on biological processes in organisms is the starting point for elucidating the role of gravity and evolutionary development of various organisms on Earth.

  7. Influence of different natural physical fields on biological processes

    NASA Astrophysics Data System (ADS)

    Mashinsky, A. L.

    2001-01-01

    In space flight conditions gravity, magnetic, and electrical fields as well as ionizing radiation change both in size, and in direction. This causes disruptions in the conduct of some physical processes, chemical reactions, and metabolism in living organisms. In these conditions organisms of different phylogenetic level change their metabolic reactions undergo changes such as disturbances in ionic exchange both in lower and in higher plants, changes in cell morphology for example, gyrosity in Proteus ( Proteus vulgaris), spatial disorientation in coleoptiles of Wheat ( Triticum aestivum) and Pea ( Pisum sativum) seedlings, mutational changes in Crepis ( Crepis capillaris) and Arabidopsis ( Arabidopsis thaliana) seedling. It has been found that even in the absence of gravity, gravireceptors determining spatial orientation in higher plants under terrestrial conditions are formed in the course of ontogenesis. Under weightlessness this system does not function and spatial orientation is determined by the light flux gradient or by the action of some other factors. Peculiarities of the formation of the gravireceptor apparatus in higher plants, amphibians, fish, and birds under space flight conditions have been observed. It has been found that the system in which responses were accompanied by phase transition have proven to be gravity-sensitive under microgravity conditions. Such reactions include also the process of photosynthesis which is the main energy production process in plants. In view of the established effects of microgravity and different natural physical fields on biological processes, it has been shown that these processes change due to the absence of initially rigid determination. The established biological effect of physical fields influence on biological processes in organisms is the starting point for elucidating the role of gravity and evolutionary development of various organisms on Earth.

  8. Humor processing in children: influence of temperament, age and IQ.

    PubMed

    Vrticka, Pascal; Black, Jessica M; Neely, Michelle; Walter Shelly, Elizabeth; Reiss, Allan L

    2013-11-01

    Emerging evidence from fMRI studies suggests that humor processing is a specific social cognitive-affective human function that comprises two stages. The first stage (cognitive humor component) involves the detection and resolution of incongruity, and is associated with activity in temporo-occipito-parietal brain areas. The second stage (emotional humor component) comprises positive feelings related to mirth/reward, and is linked with reward-related activity in mesocorticolimbic circuits. In healthy adults, humor processing was shown to be moderated by temperament traits like intro-/extraversion, neuroticism, or social anxiety, representing risk factors for psychopathology. However, comparable data from early developmental stages is crucially lacking. Here, we report for the first time data from 22 children (ages 6 to 13) revealing an influence of temperament on humor processing. Specifically, we assessed the effects of Emotionality, Shyness, and Sociability, which are analogous to neuroticism, behavioral inhibition/fear and extraversion in adults. We found Emotionality to be positively, but Shyness negatively associated with brain activity linked with both cognitive and emotional humor components. In addition, Shyness and Sociability were positively related to activity in the periaqueductal gray region during humor processing. These findings are of potential clinical relevance regarding the early detection of childhood psychopathology. Previous data on humor processing in both adults and children furthermore suggest that intelligence (IQ) supports incongruity detection and resolution, whereas mirth and associated brain activity diminishes with increasing age. Here, we found that increasing age and IQ were linked with stronger activity to humor in brain areas implicated in the cognitive component of humor. Such data suggest that humor processing undergoes developmental changes and is moderated by higher IQ scores, both factors likely improving incongruity detection

  9. Biohydrogen and Bioethanol Production from Biodiesel-Based Glycerol by Enterobacter aerogenes in a Continuous Stir Tank Reactor.

    PubMed

    Jitrwung, Rujira; Yargeau, Viviane

    2015-05-11

    Crude glycerol from the biodiesel manufacturing process is being produced in increasing quantities due to the expanding number of biodiesel plants. It has been previously shown that, in batch mode, semi-anaerobic fermentation of crude glycerol by Enterobacter aerogenes can produce biohydrogen and bioethanol simultaneously. The present study demonstrated the possible scaling-up of this process from small batches performed in small bottles to a 3.6-L continuous stir tank reactor (CSTR). Fresh feed rate, liquid recycling, pH, mixing speed, glycerol concentration, and waste recycling were optimized for biohydrogen and bioethanol production. Results confirmed that E. aerogenes uses small amounts of oxygen under semi-anaerobic conditions for growth before using oxygen from decomposable salts, mainly NH4NO3, under anaerobic condition to produce hydrogen and ethanol. The optimal conditions were determined to be 500 rpm, pH 6.4, 18.5 g/L crude glycerol (15 g/L glycerol) and 33% liquid recycling for a fresh feed rate of 0.44 mL/min. Using these optimized conditions, the process ran at a lower media cost than previous studies, was stable after 7 days without further inoculation and resulted in yields of 0.86 mol H2/mol glycerol and 0.75 mol ethanol/mole glycerol.

  10. Biohydrogen and Bioethanol Production from Biodiesel-Based Glycerol by Enterobacter aerogenes in a Continuous Stir Tank Reactor

    PubMed Central

    Jitrwung, Rujira; Yargeau, Viviane

    2015-01-01

    Crude glycerol from the biodiesel manufacturing process is being produced in increasing quantities due to the expanding number of biodiesel plants. It has been previously shown that, in batch mode, semi-anaerobic fermentation of crude glycerol by Enterobacter aerogenes can produce biohydrogen and bioethanol simultaneously. The present study demonstrated the possible scaling-up of this process from small batches performed in small bottles to a 3.6-L continuous stir tank reactor (CSTR). Fresh feed rate, liquid recycling, pH, mixing speed, glycerol concentration, and waste recycling were optimized for biohydrogen and bioethanol production. Results confirmed that E. aerogenes uses small amounts of oxygen under semi-anaerobic conditions for growth before using oxygen from decomposable salts, mainly NH4NO3, under anaerobic condition to produce hydrogen and ethanol. The optimal conditions were determined to be 500 rpm, pH 6.4, 18.5 g/L crude glycerol (15 g/L glycerol) and 33% liquid recycling for a fresh feed rate of 0.44 mL/min. Using these optimized conditions, the process ran at a lower media cost than previous studies, was stable after 7 days without further inoculation and resulted in yields of 0.86 mol H2/mol glycerol and 0.75 mol ethanol/mole glycerol. PMID:25970750

  11. Evaluation of lignins from side-streams generated in an olive tree pruning-based biorefinery: Bioethanol production and alkaline pulping.

    PubMed

    Santos, José I; Fillat, Úrsula; Martín-Sampedro, Raquel; Eugenio, María E; Negro, María J; Ballesteros, Ignacio; Rodríguez, Alejandro; Ibarra, David

    2017-07-06

    In modern lignocellulosic-based biorefineries, carbohydrates can be transformed into biofuels and pulp and paper, whereas lignin is burned to obtain energy. However, a part of lignin could be converted into value-added products including bio-based aromatic chemicals, as well as building blocks for materials. Then, a good knowledge of lignin is necessary to define its valorisation procedure. This study characterized different lignins from side-streams produced from olive tree pruning bioethanol production (lignins collected from steam explosion pretreatment with water or phosphoric acid as catalysts, followed by simultaneous saccharification and fermentation process) and alkaline pulping (lignins recovered from kraft and soda-AQ black liquors). Together with the chemical composition, the structure of lignins was investigated by FTIR, (13)C NMR, and 2D NMR. Bioethanol lignins had clearly distinct characteristics compared to pulping lignins; a certain number of side-chain linkages (mostly alkyl-aryl ether and resinol) accompanied with lower phenolic hydroxyls content. Bioethanol lignins also showed a significant amount of carbohydrates, mainly glucose and protein impurities. By contrast, pulping lignins revealed xylose together with a dramatical reduction of side-chains (some resinol linkages survive) and thereby higher phenol content, indicating rather severe lignin degradation during alkaline pulping processes. All lignins showed a predominance of syringyl units. Copyright © 2017 Elsevier B.V. All rights reserved.

  12. [The influence of economic processes on population development].

    PubMed

    Balek, A

    1982-01-01

    The author poses the question as to what causes the fluctuations in the birthrate and in population increments in the socialist countries. In order to arrive at an answer, he first analyzes demographic development in Czechoslovakia during the period 1869-1980. By comparing the differences between demographic development in Slovakia and the Czech lands, he shows the changes in demographic processes are not essentially determined by national, historical, or other factors, but are above all a complex reflection of changes in the economic mechanism. In the 2nd part of the article, the author examines in detail economic processes influencing natality and the development of population, as well as the mechanism of mutual influence which exists between demographic and economic processes. He points out that the different causes of demographic development cannot be derived from the level of the living standard, but from its changes (and/or changes in economic development). By analyzing data for the period 1948-80, the author arrives at a more precise definition of these changes in the economy. They include, for instance, changes in the rate of growth of the national economy, changes in the ratio of accumulation and consumption, changes in the ratio of national income formation and use, changes in the structure of the living standard, changes in the development of the economy and consumption in the direction of equilibrium or disequilibrium. At the same time, the author shows how these changes act toward their mutual synthesis. In each stage of development, the decisive factor for the size of population increments and natality is whether the ratio between resources and consumption is adequate, i.e., whether the relevant structure of the living standard is in accord with it. The author also examines the time lag between influences caused by changes in the economy and natality; he demonstrates that changes in the economy are effective only in this context if they overcome a

  13. Internal model of gravity influences configural body processing.

    PubMed

    Barra, Julien; Senot, Patrice; Auclair, Laurent

    2017-01-01

    Human bodies are processed by a configural processing mechanism. Evidence supporting this claim is the body inversion effect, in which inversion impairs recognition of bodies more than other objects. Biomechanical configuration, as well as both visual and embodied expertise, has been demonstrated to play an important role in this effect. Nevertheless, the important factor of body inversion effect may also be linked to gravity orientation since gravity is one of the most fundamental constraints of our biology, behavior, and perception on Earth. The visual presentation of an inverted body in a typical body inversion paradigm turns the observed body upside down but also inverts the implicit direction of visual gravity in the scene. The orientation of visual gravity is then in conflict with the direction of actual gravity and may influence configural processing. To test this hypothesis, we dissociated the orientations of the body and of visual gravity by manipulating body posture. In a pretest we showed that it was possible to turn an avatar upside down (inversion relative to retinal coordinates) without inverting the orientation of visual gravity when the avatar stands on his/her hands. We compared the inversion effect in typical conditions (with gravity conflict when the avatar is upside down) to the inversion effect in conditions with no conflict between visual and physical gravity. The results of our experiment revealed that the inversion effect, as measured by both error rate and reaction time, was strongly reduced when there was no gravity conflict. Our results suggest that when an observed body is upside down (inversion relative to participants' retinal coordinates) but the orientation of visual gravity is not, configural processing of bodies might still be possible. In this paper, we discuss the implications of an internal model of gravity in the configural processing of observed bodies.

  14. Beyond Homophily: A Decade of Advances in Understanding Peer Influence Processes

    PubMed Central

    Brechwald, Whitney A.; Prinstein, Mitchell J.

    2013-01-01

    This article reviews empirical and theoretical contributions to a multidisciplinary understanding of peer influence processes in adolescence over the past decade. Five themes of peer influence research from this decade were identified, including a broadening of the range of behaviors for which peer influence occurs, distinguishing the sources of influence, probing the conditions under which influence is amplified/attenuated (moderators), testing theoretically based models of peer influence processes (mechanisms), and preliminary exploration of behavioral neuroscience perspectives on peer influence. This review highlights advances in each of these areas, underscores gaps in current knowledge of peer influence processes, and outlines important challenges for future research. PMID:23730122

  15. Cultural influences on social feedback processing of character traits

    PubMed Central

    Korn, Christoph W.; Fan, Yan; Zhang, Kai; Wang, Chenbo; Han, Shihui; Heekeren, Hauke R.

    2014-01-01

    Cultural differences are generally explained by how people see themselves in relation to social interaction partners. While Western culture emphasizes independence, East Asian culture emphasizes interdependence. Despite this focus on social interactions, it remains elusive how people from different cultures process feedback on their own (and on others') character traits. Here, participants of either German or Chinese origin engaged in a face-to-face interaction. Consequently, they updated their self- and other-ratings of 80 character traits (e.g., polite, pedantic) after receiving feedback from their interaction partners. To exclude potential confounds, we obtained data from German and Chinese participants in Berlin [functional magnetic resonance imaging (fMRI)] and in Beijing (behavior). We tested cultural influences on social conformity, positivity biases, and self-related neural activity. First, Chinese conformed more to social feedback than Germans (i.e., Chinese updated their trait ratings more). Second, regardless of culture, participants processed self- and other-related feedback in a positively biased way (i.e., they updated more toward desirable than toward undesirable feedback). Third, changes in self-related medial prefrontal cortex activity were greater in Germans than in Chinese during feedback processing. By investigating conformity, positivity biases, and self-related activity in relation to feedback obtained in a real-life interaction, we provide an essential step toward a unifying framework for understanding the diversity of human culture. PMID:24772075

  16. Halostable cellulase with organic solvent tolerance from Haloarcula sp. LLSG7 and its application in bioethanol fermentation using agricultural wastes.

    PubMed

    Li, Xin; Yu, Hui-Ying

    2013-12-01

    A haloarchaeal strain LLSG7 with cellulolytic activity was isolated from the saline soil of Yuncheng Salt Lake, China. Biochemical and physiological characterization along with 16S rRNA gene sequence analysis placed the isolate in the genus Haloarcula. Cellulase production was strongly influenced by the salinity of the culture medium with the maximum obtained in the presence of 25 % NaCl. Substrate specificity tests showed that the crude cellulase was a multicomponent enzyme system, and zymogram analysis revealed that five different endoglucanases were secreted by strain LLSG7. Optimal cellulase activity was at 50 °C, pH 8.0, and 20 % NaCl. In addition, it was highly active and stable over broad ranges of temperature (40-80 °C), pH (7.0-11.0), and NaCl concentration (17.5-30 %). The cellulase displayed remarkable stability in the presence of non-polar organic solvents with log P ow ≥ 1.97. The crude cellulase secreted by strain LLSG7 was further applied to hydrolyze alkali-pretreated rice straw and the enzymatic hydrolysate was used as the substrate for bioethanol fermentation by Saccharomyces cerevisiae. The yield of ethanol was 0.177 g per gram of pretreated rice straw, suggesting that it might be potentially useful for bioethanol production.

  17. High temperature simultaneous saccharification and fermentation of starch from inedible wild cassava (Manihot glaziovii) to bioethanol using Caloramator boliviensis.

    PubMed

    Moshi, Anselm P; Hosea, Ken M M; Elisante, Emrode; Mamo, G; Mattiasson, Bo

    2015-03-01

    The thermoanaerobe, Caloramator boliviensis was used to ferment starch hydrolysate from inedible wild cassava to ethanol at 60°C. A raw starch degrading α-amylase was used to hydrolyse the cassava starch. During fermentation, the organism released CO2 and H2 gases, and Gas Endeavour System was successfully used for monitoring and recording formation of these gaseous products. The bioethanol produced in stoichiometric amounts to CO2 was registered online in Gas Endeavour software and correlated strongly (R(2)=0.99) with values measured by HPLC. The organism was sensitive to cyanide that exists in cassava flour. However, after acclimatisation, it was able to grow and ferment cassava starch hydrolysate containing up to 0.2ppm cyanide. The reactor hydrogen partial pressure had influence on the bioethanol production. In fed-batch fermentation by maintaining the hydrogen partial pressure around 590Pa, the organism was able to ferment up to 76g/L glucose and produced 33g/L ethanol.

  18. Factors affecting usefulness of triticale grain for bioethanol production.

    PubMed

    Obuchowski, Wiktor; Banaszak, Zofia; Makowska, Agnieszka; Łuczak, Miłosz

    2010-11-01

    Triticale grain could be a useful material for bioethanol production. The aim of this study was to examine how grain cultivar, nitrogen fertilisation level, location and year affect the starch content in triticale grain and which method of starch determination, polarimetric, enzymatic or near-infrared transmission (NIT), gives the best prediction of real bioethanol productivity from triticale grain. It was found that the starch content in triticale grain was correlated positively with test weight and 1000-kernel weight but negatively with falling number and protein content. All factors, i.e. cultivar, nitrogen fertilisation level, location and year, as well as the intrinsic interaction between these factors, had a significant effect on the starch level in triticale grain. The NIT procedure of starch determination gave the best results in predicting the real yield of ethanol obtained on the basis of classic fermentation (95% match), while the enzymatic and polarimetric methods corresponded with the real results at levels of 89-90 and 78-82% respectively. Grain growth conditions related to location and nitrogen fertilisation level had the most noticeable effect on grain starch content, while grain yield per hectare had the most significant effect on ethanol productivity. 2010 Society of Chemical Industry

  19. Spark-eroded particles: Influence of processing parameters

    NASA Astrophysics Data System (ADS)

    Carrey, J.; Radousky, H. B.; Berkowitz, A. E.

    2004-02-01

    Ni particles were prepared by spark erosion in a fixed-gap apparatus, and in the usual "shaker-pot" assembly, in an investigation of the influence of various processing parameters on the particles' properties. The sizes of the particles were studied as functions of spark energies ranging from 10 μJ to 1 J, and a scaling relation derived from a simple model was verified. Several different static and rotating electrode configurations were compared with respect to their suitability for producing significant yields of small particles. The advantages of stirring the dielectric with the fixed-gap apparatus and of rotating the electrodes were demonstrated. Water, kerosene, and liquid argon and nitrogen were used as dielectric liquids. When compounds were formed, the reaction with the dielectric proceeded inversely with particle size. Spark erosion in kerosene at low spark energies, followed by annealing, proved to be an effective method to produce fine nickel particles.

  20. The influence of musical experience on lateralisation of auditory processing.

    PubMed

    Spajdel, Marián; Jariabková, Katarína; Riecanský, Igor

    2007-11-01

    The influence of musical experience on free-recall dichotic listening to environmental sounds, two-tone sequences, and consonant-vowel (CV) syllables was investigated. A total of 60 healthy right-handed participants were divided into two groups according to their active musical competence ("musicians" and "non-musicians"). In both groups, we found a left ear advantage (LEA) for nonverbal stimuli (environmental sounds and two-tone sequences) and a right ear advantage (REA) for CV syllables. Dichotic listening to environmental sounds was uninfluenced by musical experience. The total accuracy of recall for two-tone sequences was higher in musicians than in non-musicians but the lateralisation was similar in both groups. For CV syllables a lower REA was found in male but not female musicians in comparison to non-musicians. The results indicate a specific sex-dependent effect of musical experience on lateralisation of phonological auditory processing.

  1. Influence of the Target - Density Effects on Electron - Capture Processes

    SciTech Connect

    Tolstikhina, I.Yu.; Shevelko, V.P.

    2004-12-01

    The influence of the target density on the electron-capture (EC) processes in collisions of fast ions with atoms and molecules is considered. The partial EC cross sections {sigma}n on the principal quantum number n of the scattered projectile, as well as the total {sigma}tot values are calculated for highly charged ions interacting with gaseous and solid targets in the energy range of E = 100 keV/amu to 10 MeV/amu. It is shown that with the target density increasing, the population of the excited states of the scattered projectiles, formed via the EC channel, is suppressed due to projectile ionization by the target particles and, as a result, the effective EC cross sections drastically decrease.

  2. Family Process and Peer Influences on Substance Use by Adolescents

    PubMed Central

    Loke, Alice Yuen; Mak, Yim-wah

    2013-01-01

    This study explores the association of family process and peer influences with risk behaviors of adolescents. A total of 805 students were recruited from secondary schools. The results showed that adolescents who have parents who are “authoritarian” (OR = 1.856) were more likely to smoke. Adolescents who have conflicts with their parents (OR = 1.423) were more likely to drink. Those who have parents who are “permissive” were less likely to drink (OR = 0.885). Having friends who smoked (OR = 5.446) or drank (OR = 1.894), and friends’ invitation to smoke (OR = 10.455) or drink (OR = 11.825) were the dominant contributors to adolescent smoking and drinking. Interventions are needed that recognize the strength of the parent-child relationship, as well as strengthen family functioning through improved interpersonal, parenting, and monitoring skills. PMID:23985772

  3. The influence of process parameters on electromigration lifetime statistics

    NASA Astrophysics Data System (ADS)

    Hauschildt, M.; Gall, M.; Justison, P.; Hernandez, R.; Ho, P. S.

    2008-08-01

    Even after the successful introduction of Cu-based metallization, the electromigration failure risk has remained one of the important reliability concerns for advanced process technologies mostly due to ever increasing operating current densities. The main factors that require understanding are the activation energy related to the dominating diffusion mechanism, the median lifetimes, and the lognormal standard deviation sigma of experimentally obtained lifetime distributions. This study investigates the effect of different process parameters on electromigration lifetime statistics in Cu interconnects. First, the failure distributions of single damascene interconnects with smaller line height are examined, followed by an analysis of the influence of different passivation layers on electromigration statistics. A third part focuses on samples with dual damascene technology. It is observed that the first two process modifications change the median time to failure but do not alter the sigma value. Geometrical and kinetic models developed to describe the electromigration characteristics in Cu/SiN interconnects are successfully employed to explain this observation. These models imply that the lifetime statistics depend on variations in void sizes, geometrical and experimental factors of the electromigration test, and kinetic aspects of the mass transport process. The sigma value in dual damascene interconnects is found to be larger compared to corresponding single damascene structures as a result of an increase in possible void shapes and sizes for void growth into the via in addition to evolution along the line. Furthermore, simulations of expected characteristics of lifetime distributions for future technology nodes using the above models and current electromigration data are discussed.

  4. Influence of the Mold Current on the Electroslag Remelting Process

    NASA Astrophysics Data System (ADS)

    Hugo, Mathilde; Dussoubs, Bernard; Jardy, Alain; Escaffre, Jessica; Poisson, Henri

    2016-08-01

    The electroslag remelting process is widely used to produce high value-added alloys. The use of numerical simulation has proven to be a valuable way to improve its understanding. In collaboration with Aubert & Duval, the Institute Jean Lamour has developed a numerical transient model of the process. The consumable electrode is remelted within a mold assumed to be electrically insulated by the solidified slag skin. However, this assumption has been challenged by some recent studies: the solidified slag skin may actually allow a part of the melting current to reach the mold. In this paper, the evolution of our model, in order to take into account this possibility, is presented and discussed. Numerical results are compared with experimental data, while several sensitivity studies show the influence of some slag properties and operating parameters on the quality of the ingot. Even, a weakly conductive solidified slag skin at the inner surface of the mold may be responsible for a non-negligible amount of current circulating between the slag and crucible, which in turn modifies the fluid flow and heat transfer in the slag and ingot liquid pool. The fraction of current concerned depends mainly on the electrical conductivities of both the liquid and solidified slag.

  5. Influence of processing parameters on the quality of soycurd (tofu).

    PubMed

    Rekha, C R; Vijayalakshmi, G

    2013-02-01

    Tofu, a non-fermented soybean curd is a nutritious and digestible product with a high quality protein. Tofu making procedure includes soaking of beans, grinding, filtering, boiling, coagulating and moulding. The flavour, quality and the texture of tofu produced is significantly influenced by its processing parameters. Studies were carried out on the processing parameters like solid content of milk, thermal treatment of soybeans with sodium bicarbonate, stirring time after adding coagulant and moulding of tofu on the texture and quality of tofu. Our studies showed that the texture of the final product depended on the solid content of milk before coagulation. Pretreatment of soybeans with sodium bicarbonate, for 10 min and milk obtained with low solid content of 7° Brix resulted in regular, smooth textured tofu with less beany flavour. Duration of stirring during coagulation and moulding parameters had a significant effect on the yield of tofu. Stirring the milk after adding the coagulant for 5 s before settling and pressing the tofu with a load of 1,000 g initially for 15 min followed by 500 g for another 15 min, yielded (22.6 g/100 ml of milk) soft textured firm tofu.

  6. Influence of the processed sunflower oil on the cement properties

    NASA Astrophysics Data System (ADS)

    Fleysher, A. U.; Tokarchuk, V. V.; Sviderskiy, V. A.

    2015-01-01

    Used oils (vegetable oil, animal oil, engine oil, etc.), which are essentially industrial wastes, have found application as secondary raw materials in some braches of industry. In particular, the only well-known and commonly-used way of utilizing wastes of vegetable oils is to apply them as raw materials in the production of biodiesel. The goal of the present study is to develop a conceptually new way of vegetable oil wastes utilization in the building industry. The test admixture D-148 was obtained from the processing of wastes of sunflower oil and it mainly consists of fatty acid diethanolamide. The test admixture was added to the cement system for the purpose of studying its influence on water demand, flowability, setting times, compressive strength and moisture adsorption. The test admixture D-148 at the optimal content 0. 2 weight % causes 10% decrease in water demand, 1.7 time increase in flowability (namely spread diameter), 23% increase in grade strength and 34% decrease in moisture adsorption. The results of the present investigation make it possible to consider the final product of the waste sunflower oil processing as multifunctional plasticizing-waterproofing admixture.

  7. Influence of processing parameters on morphology of polymethoxyflavone in emulsions.

    PubMed

    Ting, Yuwen; Li, Colin C; Wang, Yin; Ho, Chi-Tang; Huang, Qingrong

    2015-01-21

    Polymethoxyflavones (PMFs) are groups of compounds isolated from citrus peels that have been documented with wide arrays of health-promoting bioactivities. Because of their hydrophobic structure and high melting point, crystallized PMFs usually have poor systemic bioavailability when consumed orally. To improve the oral efficiency of PMFs, a viscoelastic emulsion system was formulated. Because of the crystalline nature, the inclusion of PMFs into the emulsion system faces great challenges in having sufficient loading capacity and stabilities. In this study, the process of optimizing the quality of emulsion-based formulation intended for PMF oral delivery was systematically studied. With alteration of the PMF loading concentration, processing temperature, and pressure, the emulsion with the desired droplet and crystal size can be effectively fabricated. Moreover, storage temperatures significantly influenced the stability of the crystal-containing emulsion system. The results from this study are a good illustration of system optimization and serve as a great reference for future formulation design of other hydrophobic crystalline compounds.

  8. Influence of global climatic processes on environment The Arctic seas

    NASA Astrophysics Data System (ADS)

    Kholmyansky, Mikhael; Anokhin, Vladimir; Kartashov, Alexandr

    2016-04-01

    One of the most actual problems of the present is changes of environment of Arctic regions under the influence of global climatic processes. Authors as a result of the works executed by them in different areas of the Russian Arctic regions, have received the materials characterising intensity of these processes. Complex researches are carried out on water area and in a coastal zone the White, the Barents, the Kara and the East-Siberian seas, on lake water areas of subarctic region since 1972 on the present. Into structure of researches enter: hydrophysical, cryological observations, direct measurements of temperatures, the analysis of the drill data, electrometric definitions of the parametres of a frozen zone, lithodynamic and geochemical definitions, geophysical investigations of boreholes, studying of glaciers on the basis of visual observations and the analysis of photographs. The obtained data allows to estimate change of temperature of a water layer, deposits and benthonic horizon of atmosphere for last 25 years. On the average they make 0,38⁰C for sea waters, 0,23⁰C for friable deposits and 0,72⁰C for atmosphere. Under the influence of temperature changes in hydrosphere and lithosphere of a shelf cryolithic zone changes the characteristics. It is possible to note depth increase of roof position of the cryolithic zone on the most part of the studied water area. Modern fast rise in temperature high-ice rocks composing coast, has led to avalanche process thermo - denudation and to receipt in the sea of quantity of a material of 1978 three times exceeding level Rise in temperature involves appreciable deviation borders of the Arctic glacial covers. On our monitoring measurements change of the maintenance of oxygen in benthonic area towards increase that is connected with reduction of the general salinity of waters at the expense of fresh water arriving at ice thawing is noticed. It, in turn, leads to change of a biogene part of ecosystem. The executed

  9. Neoliberalist influences on nursing hospital work process and organization.

    PubMed

    Souza, Norma Valéria Dantas de Oliveira; Gonçalves, Francisco Gleidson de Azevedo; Pires, Ariane da Silva; David, Helena Maria Scherlowski Leal

    2017-01-01

    To describe and analyze the influence of the neoliberal economic and political model on the nursing hospital work process and organization. Qualitative descriptive research, having as its scenery a university hospital. The subjects were 34 nursing workers. The data collection took place from March to July 2013, through semi-structured interview. The data treatment technique used was content analysis, which brought up the following category: working conditions precariousness and its consequences to the hospital work process and organization in the neoliberal context. The consequences of neoliberalism on hospital work process and organization were highlighted, being observed physical structure, human resources and material inadequacies that harms the assistance quality. In addition to wage decrease that cause the need of second jobs and work overload. There is a significant influence of the neoliberal model on hospital work, resulting on working conditions precariousness. Descrever e analisar a influência do modelo econômico e político neoliberal na organização e no processo de trabalho hospitalar de enfermagem. Pesquisa qualitativa e descritiva, tendo como cenário um hospital universitário. Os participantes foram 34 trabalhadores de enfermagem. A coleta ocorreu de março a julho de 2013, por meio de entrevista semiestruturada. A técnica de tratamento dos dados foi a análise de conteúdo, que fez emergir a seguinte categoria: precarização das condições laborais e suas repercussões para organização e processo de trabalho hospitalar no contexto neoliberal. Evidenciaram-se repercussões do neoliberalismo na organização e no processo de trabalho hospitalar, verificando-se inadequações na estrutura física, nos recursos humanos e materiais, que afetavam a qualidade da assistência. Além de perdas salariais que levam à necessidade de outros empregos e sobrecarga de trabalho. Há forte influência do modelo neoliberal no trabalho hospitalar, resultando

  10. Influence of emotional processing on working memory in schizophrenia.

    PubMed

    Becerril, Karla; Barch, Deanna

    2011-09-01

    Research on emotional processing in schizophrenia suggests relatively intact subjective responses to affective stimuli "in the moment." However, neuroimaging evidence suggests diminished activation in brain regions associated with emotional processing in schizophrenia. We asked whether given a more vulnerable cognitive system in schizophrenia, individuals with this disorder would show increased or decreased modulation of working memory (WM) as a function of the emotional content of stimuli compared with healthy control subjects. In addition, we examined whether higher anhedonia levels were associated with a diminished impact of emotion on behavioral and brain activation responses. In the present study, 38 individuals with schizophrenia and 32 healthy individuals completed blocks of a 2-back WM task in a functional magnetic resonance imaging scanning session. Blocks contained faces displaying either only neutral stimuli or neutral and emotional stimuli (happy or fearful faces), randomly intermixed and occurring both as targets and non-targets. Both groups showed higher accuracy but slower reaction time for negative compared to neutral stimuli. Individuals with schizophrenia showed intact amygdala activity in response to emotionally evocative stimuli, but demonstrated altered dorsolateral prefrontal cortex (DLPFC) and hippocampal activity while performing an emotionally loaded WM-task. Higher levels of social anhedonia were associated with diminished amygdala responses to emotional stimuli and increased DLPFC activity in individuals with schizophrenia. Emotional arousal may challenge dorsal-frontal control systems, which may have both beneficial and detrimental influences. Our findings suggest that disturbances in emotional processing in schizophrenia relate to alterations in emotion-cognition interactions rather than to the perception and subjective experience of emotion per se.

  11. The influence of contrast on coherent motion processing in dyslexia.

    PubMed

    Conlon, Elizabeth G; Lilleskaret, Gry; Wright, Craig M; Power, Garry F

    2012-06-01

    The aim of the experiments was to investigate how manipulating the contrast of the signal and noise dots in a random dot kinematogram (RDK), influenced on motion coherence thresholds in adults with dyslexia. In the first of two experiments, coherent motion thresholds were measured when the contrasts of the signal and noise dots in an RDK were manipulated. A significantly greater processing benefit was found for the group with dyslexia than a control group when the signal dots were of higher contrast than the noise dots. However, a significant processing disadvantage was found for the group with dyslexia relative to the control group when the signal dots were of lower contrast than the noise dots. These findings were interpreted as supporting evidence for the noise exclusion hypothesis of dyslexia. In Experiment 2, the effect on coherent motion thresholds of presenting a cue that alerted observers to which stimuli, high or low contrast contained the signals dots was investigated. When the cue directed attention to low contrast signal dots presented in high contrast noise, coherent motion thresholds were only enhanced for the group with dyslexia. This manipulation produced equivalent coherent motion thresholds in the reader groups. In other conditions, the group with dyslexia had significantly higher coherent motion thresholds than the control group. It was concluded that adults with dyslexia who show evidence of a coherent motion deficit (37% of the dyslexia group in each experiment), have a specific difficulty in noise exclusion. This appears to occur as consequence of a sensory processing deficit in the magnocellular or dorsal stream.

  12. Influence of Emotional Processing on Working Memory in Schizophrenia

    PubMed Central

    Becerril, Karla; Barch, Deanna

    2011-01-01

    Research on emotional processing in schizophrenia suggests relatively intact subjective responses to affective stimuli “in the moment.” However, neuroimaging evidence suggests diminished activation in brain regions associated with emotional processing in schizophrenia. We asked whether given a more vulnerable cognitive system in schizophrenia, individuals with this disorder would show increased or decreased modulation of working memory (WM) as a function of the emotional content of stimuli compared with healthy control subjects. In addition, we examined whether higher anhedonia levels were associated with a diminished impact of emotion on behavioral and brain activation responses. In the present study, 38 individuals with schizophrenia and 32 healthy individuals completed blocks of a 2-back WM task in a functional magnetic resonance imaging scanning session. Blocks contained faces displaying either only neutral stimuli or neutral and emotional stimuli (happy or fearful faces), randomly intermixed and occurring both as targets and non-targets. Both groups showed higher accuracy but slower reaction time for negative compared to neutral stimuli. Individuals with schizophrenia showed intact amygdala activity in response to emotionally evocative stimuli, but demonstrated altered dorsolateral prefrontal cortex (DLPFC) and hippocampal activity while performing an emotionally loaded WM-task. Higher levels of social anhedonia were associated with diminished amygdala responses to emotional stimuli and increased DLPFC activity in individuals with schizophrenia. Emotional arousal may challenge dorsal-frontal control systems, which may have both beneficial and detrimental influences. Our findings suggest that disturbances in emotional processing in schizophrenia relate to alterations in emotion-cognition interactions rather than to the perception and subjective experience of emotion per se. PMID:20176860

  13. Implications of the biofuels policy mandate in Thailand on water: the case of bioethanol.

    PubMed

    Gheewala, Shabbir H; Silalertruksa, Thapat; Nilsalab, Pariyapat; Mungkung, Rattanawan; Perret, Sylvain R; Chaiyawannakarn, Nuttapon

    2013-12-01

    The study assesses the implications of the bioethanol policy mandate in Thailand of producing 9 M litre ethanol per day by 2021 on water use and water deprivation. The results reveal that water footprint (WF) of bioethanol varies between 1396 and 3105 L water/L ethanol. Cassava ethanol has the highest WF followed by molasses and sugarcane ethanol, respectively. However, in terms of fresh water (especially irrigation water) consumption, molasses ethanol is highest with 699-1220 L/L ethanol. To satisfy the government plan of bioethanol production in 2021, around 1625 million m(3) of irrigation water/year will be additionally required, accounting for about 3% of the current active water storage of Thailand. Two important watersheds in the northeastern region of Thailand are found to be potentially facing serious water stress if water resources are not properly managed. Measures to reduce water footprint of bioethanol are recommended. Copyright © 2013 Elsevier Ltd. All rights reserved.

  14. Bioethanol production from dedicated energy crops and residues in Arkansas, USA

    USDA-ARS?s Scientific Manuscript database

    Globally, one of the major technological goals is cost-effective lignocellulosic ethanol production from biomass feedstocks. Lignocellulosic biomass of five dedicated energy crops and two crops residues were tested for bioethanol production using cellulose solvent-based lignocellulose fractionation...

  15. Development of glycerol-utilizing Escherichia coli strain for the production of bioethanol.

    PubMed

    Thapa, Laxmi Prasad; Lee, Sang Jun; Yoo, Hah Young; Choi, Han Suk; Park, Chulhwan; Kim, Seung Wook

    2013-08-15

    The production of bioethanol was studied using recombinant Escherichia coli with glycerol as a carbon source. Glycerol is an attractive feedstock for biofuels production since it is generated as a major byproduct in biodiesel industry; therefore, we investigated the conversion of glycerol to bioethanol using E. coli BL21 (DE3) which harbors several genes in ethanol production pathway of Enterobacter aerogenes KCTC 2190. Fermentation was carried out at 34°C for 42h, pH 7.6, using defined production medium. Under optimal conditions, bioethanol production by the recombinant E. coli BL21 (DE3), strain pEB, was two-fold (3.01g/L) greater than that (1.45g/L) by the wild-type counterpart. The results obtained in this study will provide valuable guidelines for engineering bioethanol producers. Copyright © 2013 Elsevier Inc. All rights reserved.

  16. Feasibility of Bioethanol Production From Lignocellulosic Biomass

    NASA Astrophysics Data System (ADS)

    Aunina, Zane; Bazbauers, Gatis; Valters, Karlis

    2010-01-01

    The objective of the paper is to discuss the potential of cellulosic ethanol production processes and compare them, to find the most appropriate production method for Latvia's situation, to perform theoretical calculations and to determine the potential ethanol price. In addition, price forecasts for future cellulosic and grain ethanol are compared. A feasibility estimate to determine the price of cellulosic ethanol in Latvia, if production were started in 2010, was made. The grain and cellulosic ethanol price comparison (future forecast) was made through to the year 2018.

  17. Hyporheic zone as a bioreactor: sediment heterogeneity influencing biogeochemical processes

    NASA Astrophysics Data System (ADS)

    Perujo, Nuria; Romani, Anna M.; Sanchez-Vila, Xavier

    2017-04-01

    Mediterranean fluvial systems are characterized by frequent periods of low flow or even drought. During low flow periods, water from wastewater treatment plants (WWTPs) is proportionally large in fluvial systems. River water might be vertically transported through the hyporheic zone, and then porous medium acts as a complementary treatment system since, as water infiltrates, a suite of biogeochemical processes occurs. Subsurface sediment heterogeneity plays an important role since it influences the interstitial fluxes of the medium and drives biomass growing, determining biogeochemical reactions. In this study, WWTP water was continuously infiltrated for 3 months through two porous medium tanks: one consisting of 40 cm of fine sediment (homogeneous); and another comprised of two layers of different grain size sediments (heterogeneous), 20 cm of coarse sediment in the upper part and 20 cm of fine one in the bottom. Several hydrological, physicochemical and biological parameters were measured periodically (weekly at the start of the experiment and biweekly at the end). Analysed parameters include dissolved nitrogen, phosphorus, organic carbon, and oxygen all measured at the surface, and at 5, 20 and 40 cm depth. Variations in hydraulic conductivity with time were evaluated. Sediment samples were also analysed at three depths (surface, 20 and 40 cm) to determine bacterial density, chlorophyll content, extracellular polymeric substances, and biofilm function (extracellular enzyme activities and carbon substrate utilization profiles). Preliminary results suggest hydraulic conductivity to be the main driver of the differences in the biogeochemical processes occurring in the subsurface. At the heterogeneous tank, a low nutrient reduction throughout the whole medium is measured. In this medium, high hydraulic conductivity allows for a large amount of infiltrating water, but with a small residence time. Since some biological processes are largely time-dependent, small water

  18. Production of bioethanol from carrot discards.

    PubMed

    Aimaretti, Nora R; Ybalo, Carolina V; Rojas, María L; Plou, Francisco J; Yori, Juan C

    2012-11-01

    A revalorization of discarded carrots as substrate for the production of second-generation ethanol is proposed. In order to increase the fermentable sugar concentration of the musts two strategies were studied: Strategy 1 consisted in the enzymatic hydrolysis of bagasse must and Strategy 2 by which carrots were milled, dropped into distilled water and hydrolyzed with different enzymes prior to compressing and filtering to obtain carrot must. By applying Strategy 2 using 0.05% (v/v) of the enzyme Optimase CX255 at 70°C and pH 5.5 during 2.5h, the fermentable sugars extracted increased 3.5 times. In this way, the production of 77.5L of ethanol for each ton of discarded carrots was achieved. This process yielded bagasse as byproduct, which could be used for animal feed. Copyright © 2012 Elsevier Ltd. All rights reserved.

  19. Enhanced hydrolysis of lignocellulosic biomass: Bi-functional enzyme complexes expressed in Pichia pastoris improve bioethanol production from Miscanthus sinensis.

    PubMed

    Shin, Sang Kyu; Hyeon, Jeong Eun; Kim, Young In; Kang, Dea Hee; Kim, Seung Wook; Park, Chulhwan; Han, Sung Ok

    2015-12-01

    Lignocellulosic biomass is the most abundant utilizable natural resource. In the process of bioethanol production from lignocellulosic biomass, an efficient hydrolysis of cellulose and hemicellulose to release hexose and pentose is essential. We have developed a strain of Pichia pastoris that can produce ethanol via pentose and hexose using an assembly of enzyme complexes. The use of enzyme complexes is one of the strategies for effective lignocellulosic biomass hydrolysis. Xylanase XynB from Clostridium cellulovorans and a chimeric endoglucanase cCelE from Clostridium thermocellum were selected as enzyme subunits, and were bound to a recombinant scaffolding protein mini-CbpA from C. cellulovorans to assemble the enzyme complexes. These complexes efficiently degraded xylan and carboxymethylcellulose (CMC), producing approximately 1.18 and 1.07 g/L ethanol from each substrate, respectively, which is 2.3-fold and 2.7-fold higher than that of the free-enzyme expressing strain. Miscanthus sinensis was investigated as the lignocellulosic biomass for producing bioethanol, and 1.08 g/L ethanol was produced using our recombinant P. pastoris strain, which is approximately 1.9-fold higher than that of the wild-type strain. In future research, construction of enzyme complexes containing various hydrolysis enzymes could be used to develop biocatalysts that can completely degrade lignocellulosic biomass into valuable products such as biofuels.

  20. Interconnected Hierarchical Porous Carbon from Lignin-Derived Byproducts of Bioethanol Production for Ultra-High Performance Supercapacitors.

    PubMed

    Zhang, Liming; You, Tingting; Zhou, Tian; Zhou, Xia; Xu, Feng

    2016-06-08

    The advent of bioethanol production has generated abundant lignin-derived byproducts which contain proteins and polysaccharides. These byproducts are inapplicable for direct material applications. In this study, lignin-derived byproducts were used for the first time as carbon precursors to construct an interconnected hierarchical porous nitrogen-doped carbon (HPNC) via hydrothermal treatment and activation. The obtained HPNC exhibited favorable features for supercapacitor applications, such as hierarchical bowl-like pore structures, a large specific surface area of 2218 m(2) g(-1), a high electronic conductivity of 4.8 S cm(-1), and a nitrogen doping content of 3.4%. HPNC-based supercapacitors in a 6 M KOH aqueous electrolyte exhibited high-rate performance with a high specific capacitance of 312 F g(-1) at 1 A g(-1) and 81% retention at 80 A g(-1) as well as an excellent cyclic life of 98% initial capacitance after 20 000 cycles at 10 A g(-1). Moreover, HPNC-based supercapacitors in the ionic liquid electrolyte of EMI-BF4 displayed an enhanced energy density of 44.7 Wh kg(-1) (remaining 74% of max value) at an ultrahigh power density of 73.1 kW kg(-1). The proposed strategy may facilitate lignin utilization and lead to a green bioethanol production process.

  1. Influence of thermal processing on the allergenicity of peanut proteins.

    PubMed

    Mondoulet, L; Paty, E; Drumare, M F; Ah-Leung, S; Scheinmann, P; Willemot, R M; Wal, J M; Bernard, H

    2005-06-01

    Peanuts are one of the most common and severe food allergens. Nevertheless, the occurrence of peanut allergy varies between countries and depends on both the exposure and the way peanuts are consumed. Processing is known to influence the allergenicity of peanut proteins. The aim of this study was to assess the effect of thermal processing on the IgE-binding capacity of whole peanut protein extracts and of the major peanut allergens Ara h 1 and Ara h 2. Whole proteins, Ara h 1, and Ara h 2 were extracted and purified from raw, roasted and boiled peanuts using selective precipitation and multiple chromatographic steps, and were then characterized by electrophoresis and mass spectrometry. The immunoreactivity of whole peanut extracts and purified proteins was analyzed by the enzyme allergosorbent test (EAST) and EAST inhibition using the sera of 37 peanut-allergic patients. The composition of the whole protein extracts was modified after heat processing, especially after boiling. The electrophoretic pattern showed protein bands of low molecular weight that were less marked in boiled than in raw and roasted peanuts. The same low-molecular-weight proteins were found in the cooking water of peanuts. Whole peanut protein extracts obtained after the different processes were all recognized by the IgE of the 37 patients. The IgE-binding capacity of the whole peanut protein extracts prepared from boiled peanuts was 2-fold lower than that of the extracts prepared from raw and roasted peanuts. No significant difference was observed between protein extracts from raw and roasted peanuts. It is noteworthy that the proteins present in the cooking water were also recognized by the IgE of peanut-allergic patients. IgE immunoreactivity of purified Ara h 1 and Ara h 2 prepared from roasted peanuts was higher than that of their counterparts prepared from raw and boiled peanuts. The IgE-binding capacity of purified Ara h 1 and Ara h 2 was altered by heat treatment and in particular was

  2. The Public Acceptance of Biofuels and Bioethanol from Straw- how does this affect Geoscience

    NASA Astrophysics Data System (ADS)

    Jäger, Alexander; Ortner, Tina; Kahr, Heike

    2015-04-01

    The Public Acceptance of Biofuels and Bioethanol from Straw- how does this affect Geoscience The successful use of bioethanol as a fuel requires its widespread acceptance by consumers. Due to the planned introduction of a 10 per cent proportion of bioethanol in petrol in Austria, the University of Applied Sciences Upper Austria carried out a representative opinion poll to collect information on the population's acceptance of biofuels. Based on this survey, interviews with important stakeholders were held to discuss the results and collect recommendations on how to increase the information level and acceptance. The results indicate that there is a lack of interest and information about biofuels, especially among young people and women. First generation bioethanol is strongly associated with the waste of food resources, but the acceptance of the second generation, produced from agricultural remnants like straw from wheat or corn, is considerably higher. The interviewees see more transparent, objective and less technical information about biofuels as an essential way to raise the information level and acceptance rate. As the production of bioethanol from straw is now economically feasible, there is one major scientific question to answer: In which way does the withdrawal of straw from the fields affect the formation of humus and, therefore, the quality of the soil? An interdisciplinary approach of researchers in the fields of bioethanol production, geoscience and agriculture in combination with political decision makers are required to make the technologies of renewable bioenergy acceptable to the population.

  3. Severe burn injuries caused by bioethanol-design fireplaces-an overview on recreational fire threats.

    PubMed

    Kraemer, Robert; Knobloch, Karsten; Lorenzen, Johan; Breuing, Karl H; Koennecker, Soeren; Rennekampff, Hans-Oliver; Vogt, Peter M

    2011-01-01

    Commercially available bioethanol-fueled fireplaces have become increasingly popular additions for interior home decoration in Europe and more recently in the United States. These fireplaces are advertised as smokeless, ecologically friendly, and do not require professional installation, formal gas lines, or venting. Although manufacturers and businesses promote their safety, recent presentations of injuries have alerted the authors to the relevant danger bioethanol fireplaces can pose for the incautious user. Are bioethanol fireplaces going to become the future threat in domestic burn accidents beside common barbeque burns? A Medline literature search on barbeque and domestic fireplace accidents was performed to compare and stratify the injury patterns reported and to identify a risk profile for contemporary bioethanol-fueled fireplaces. To exemplify, two representative clinical cases of severe burn accidents caused by bioethanol-fueled fireplaces, both treated in the burn unit of the authors, are being presented. Design fireplaces are being recognized as an increasing source of fuel and fire-related danger in the home. This risk may be underestimated by the uninformed customer, resulting in severe burn injuries. Because bioethanol-fueled fireplaces have become more commonplace, they may overtake barbecue-related injury as the most common domestic burn injury.

  4. Long-term bioethanol system and its implications on GHG emissions: a case study of Thailand.

    PubMed

    Silalertruksa, Thapat; Gheewala, Shabbir H

    2011-06-01

    The study evaluates greenhouse gas (GHG) emissions performance of future bioethanol systems in Thailand to ascertain whether bioethanol for transport could help the country mitigate a global warming impact. GHG emission factors of bioethanol derived from cassava, molasses, and sugar cane are analyzed using 12 scenarios covering the critical variables possibly affecting the GHG performance, i.e., (1) the possible direct land use change caused by expanding feedstock cultivation areas; (2) types of energy carriers used in ethanol plants; and (3) waste utilization, e.g., biogas recovery and dry distillers grains with solubles (DDGS) production. The assessment reveals that GHG performance of a Thai bioethanol system is inclined to decrease in the long run due to the effects from the expansion of plantation areas to satisfy the deficit of cassava and molasses. Therefore, bioethanol will contribute to the country's strategic plan on GHG mitigation in the transportation sector only if the production systems are sustainably managed, i.e., coal replaced by biomass in ethanol plants, biogas recovery, and adoption of improved agricultural practices to increase crop productivity without intensification of chemical fertilizers. Achieving the year 2022 government policy targets for bioethanol with recommended measures would help mitigate GHG emissions up to 4.6 Gg CO(2)-eq per year.

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

    PubMed

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

    2012-03-15

    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 optimised solid-state straw culture conditions, experiments were conducted that compared fungal strains in terms of their growth, enzyme activities (cellulases, xylanase and alcohol dehydrogenase) and yield of bioethanol and the undesirable by-products acetic acid and xylitol. Significant inter-strain divergence was recorded in regards to the capacity of studied F. oxysporum strains to produce alcohol from untreated straw. No correlation was observed between bioethanol synthesis and either the biomass production or microbial enzyme activity. A strong correlation was observed between both acetic acid and xylitol production and bioethanol yield. The level of diversity recorded in the alcohol production capacity among closely-related microorganism means that a targeted screening of populations of selected microbial species could greatly improve bioprocessing yields, in terms of providing both new host strains and candidate genes for the bioethanol industry.

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

    PubMed Central

    2012-01-01

    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 optimised solid-state straw culture conditions, experiments were conducted that compared fungal strains in terms of their growth, enzyme activities (cellulases, xylanase and alcohol dehydrogenase) and yield of bioethanol and the undesirable by-products acetic acid and xylitol. Significant inter-strain divergence was recorded in regards to the capacity of studied F. oxysporum strains to produce alcohol from untreated straw. No correlation was observed between bioethanol synthesis and either the biomass production or microbial enzyme activity. A strong correlation was observed between both acetic acid and xylitol production and bioethanol yield. The level of diversity recorded in the alcohol production capacity among closely-related microorganism means that a targeted screening of populations of selected microbial species could greatly improve bioprocessing yields, in terms of providing both new host strains and candidate genes for the bioethanol industry. PMID:22420408

  7. Influence of Manufacturing Processes on the Performance of Phantom Lungs

    SciTech Connect

    Traub, Richard J.

    2008-10-01

    Chest counting is an important tool for estimating the radiation dose to individuals who have inhaled radioactive materials. Chest counting systems are calibrated by counting the activity in the lungs of phantoms where the activity in the phantom lungs is known. In the United States a commonly used calibration phantom was developed at the Lawrence Livermore National Laboratory and is referred to as the Livermore Torso Phantom. An important feature of this phantom is that the phantom lungs can be interchanged so that the counting system can be challenged by different combinations of radionuclides and activity. Phantom lungs are made from lung tissue substitutes whose constituents are foaming plastics and various adjuvants selected to make the lung tissue substitute similar to normal healthy lung tissue. Some of the properties of phantom lungs cannot be readily controlled by phantom lung manufacturers. Some, such as density, are a complex function of the manufacturing process, while others, such as elemental composition of the bulk plastic are controlled by the plastics manufacturer without input, or knowledge of the phantom manufacturer. Despite the fact that some of these items cannot be controlled, they can be measured and accounted for. This report describes how manufacturing processes can influence the performance of phantom lungs. It is proposed that a metric that describes the brightness of the lung be employed by the phantom lung manufacturer to determine how well the phantom lung approximates the characteristics of a human lung. For many purposes, the linear attenuation of the lung tissue substitute is an appropriate surrogate for the brightness.

  8. Prospective technology on bioethanol production from photofermentation.

    PubMed

    Costa, Rosangela Lucio; Oliveira, Thamayne Valadares; Ferreira, Juliana de Souza; Cardoso, Vicelma Luiz; Batista, Fabiana Regina Xavier

    2015-04-01

    The most important global demand is the energy supply from alternative source. Ethanol may be considered an environmental friendly fuel that has been produced by feedstock. The production of ethanol by microalgae represent a process with reduced environmental impact with efficient CO2 fixation and requiring less arable land. This work studied the production of ethanol from green alga Chlamydomonas reinhardtii through the cellular metabolism in a light/dark cycle at 25 °C in a TAP medium with sulfur depletion. The parameters evaluated were inoculum concentration and the medium supplementation with mixotrophic carbon sources. The combination of C.reinhardtii and Rhodobacter capsulatus through a hybrid or co-culture systems was also investigated as well. C.reinhardtii maintained in TAP-S produced 19.25±4.16 g/L (ethanol). In addition, in a hybrid system, with medium initially supplemented with milk whey permeated and the algal effluent used by R. capsulatus, the ethanol production achieved 19.94±2.67 g/L.

  9. The implications of thermomechanical processing for microbiologically influenced corrosion

    SciTech Connect

    Walsh, D.W.

    1999-11-01

    This work examined the effect of systematic variation in the amounts of cerium, sulfur and silicon on corrosion resistance in an AISI 8630 base material and weldments exposed to sterile and biologically active anaerobic aqueous solutions. Significant correlation between microbiologically influenced corrosion (MIC) susceptibility and sulfide inclusion size, shape, chemical stability and spatial distribution were found in these materials. In addition, significant correlation was found between these factors and bacterial attachment, particularly during a critical time period in film evolution. These factors were found to affect the evolution of microbial consortia at metal surfaces and subsequent corrosion at attachment sites, as measured by pit initiation and maximum pit size. The results suggest mitigation strategies based on microstructural design. A two-level, three-factor full factorial experiment, with AISI 8630 (UNS G86300) as the master composition, was used to relate minor element composition to both MIC susceptibility and microbial attachment in weld composite zones, partially melted zones (PMZ) and adjacent base metal regions. In all cases studied, MIC susceptibility was greatest in the PMZ. In addition, the MIC susceptibility of materials tested was significantly altered by differences in fabrication procedure as measured by changes to heat input. Samples exposed to sterile solutions were significantly less corroded. Higher energy density processes and lower heat inputs diminished MIC sensitivity. In both base metal and welded samples the addition of Cerium was found to diminish MIC susceptibility. Cerium creates this benefit through its profound effect on inclusion geometry, chemical stability and thermal stability.

  10. Influence of sensory neuropeptides on human cutaneous wound healing process.

    PubMed

    Chéret, J; Lebonvallet, N; Buhé, V; Carre, J L; Misery, L; Le Gall-Ianotto, C

    2014-06-01

    Close interactions exist between primary sensory neurons of the peripheral nervous system (PNS) and skin cells. The PNS may be implicated in the modulation of different skin functions as wound healing. Study the influence of sensory neurons in human cutaneous wound healing. We incubated injured human skin explants either with rat primary sensory neurons from dorsal root ganglia (DRG) or different neuropeptides (vasoactive intestinal peptide or VIP, calcitonin gene-related peptide or CGRP, substance P or SP) at various concentrations. Then we evaluated their effects on the proliferative and extracellular matrix (ECM) remodeling phases, dermal fibroblasts adhesion and differentiation into myofibroblasts. Thus, DRG and all studied neuromediators increased fibroblasts and keratinocytes proliferation and act on the expression ratio between collagen type I and type III in favor of collagen I, particularly between the 3rd and 7th day of culture. Furthermore, the enzymatic activities of matrix metalloprotesases (MMP-2 and MMP-9) were increased in the first days of wound healing process. Finally, the adhesion of human dermal fibroblasts and their differentiation into myofibroblasts were promoted after incubation with neuromediators. Interestingly, the most potent concentrations for each tested molecules, were the lowest concentrations, corresponding to physiological concentrations. Sensory neurons and their derived-neuropeptides are able to promote skin wound healing. Copyright © 2014 Japanese Society for Investigative Dermatology. Published by Elsevier Ireland Ltd. All rights reserved.

  11. Coastal processes influencing water quality at Great Lakes beaches

    USGS Publications Warehouse

    ,

    2013-01-01

    In a series of studies along the Great Lakes, U.S. Geological Survey scientists are examining the physical processes that influence concentrations of fecal indicator bacteria and related pathogens at recreational beaches. These studies aim to estimate human health risk, improve management strategies, and understand the fate and transport of microbes in the nearshore area. It was determined that embayed beaches act as traps, accumulating Escherichia coli (E. coli) and other bacteria in the basin and even in beach sand. Further, shear stress and wave run-up could resuspend accumulated bacteria, leading to water-contamination events. These findings are being used to target beach design and circulation projects. In previous research, it was determined that E. coli followed a diurnal pattern, with concentrations decreasing throughout the day, largely owing to solar inactivation, but rebounding overnight. Studies at a Chicago beach identified the impact of wave-induced mass transport on this phenomenon, a finding that will extend our understanding of bacterial fate in the natural environment. In another series of studies, scientists examined the impact of river outfalls on bacteria concentrations, using mechanistic and empirical modeling. Through these studies, the models can indicate range and extent of impact, given E. coli concentration in the source water. These findings have been extended to extended lengths of coastlines and have been applied in beach management using empirical predictive modeling. Together, these studies are helping scientists identify and eliminate threats to human and coastal health.

  12. Operational strategies for producing bioethanol in a continuous single-stage reactor.

    PubMed

    López-Abelairas, M; Pena, R; Fleischhacker, L; Lú-Chau, T A; Lema, J M

    2013-12-01

    Novel strategies to facilitate the transition from batch to continuous simultaneous saccharification and fermentation were studied in this work. Implementing these strategies in bioethanol production plants to change production to a continuous mode will avoid large modifications in the process configuration. Therefore, experiments were carried out in a single-stage reactor applying strategies that favour a priori viability of yeast and stability of the process. The effects of (a) hydraulic residence time (HRT), (b) anaerobic and microaerobic operation, (c) inoculation strategy and (d) growth inhibition due to high ethanol concentrations were evaluated. The highest ethanol concentration (6.3 % w/w) was achieved during anaerobic operation, with reinoculations every 3-4 days and an HRT of 60 h; however, the processes suffered severe instability under these conditions. The greatest productivity and stability of the process was achieved using periodic microaeration and an HRT of 36 h (0.169 % ethanol weight/h), overcoming the result obtained during batch operation (0.128 % ethanol weight/h).

  13. Robust industrial Saccharomyces cerevisiae strains for very high gravity bio-ethanol fermentations.

    PubMed

    Pereira, Francisco B; Guimarães, Pedro M R; Teixeira, José A; Domingues, Lucília

    2011-08-01

    The application and physiological background of two industrial Saccharomyces cerevisiae strains, isolated from harsh industrial environments, were studied in Very High Gravity (VHG) bio-ethanol fermentations. VHG laboratory fermentations, mimicking industrially relevant conditions, were performed with PE-2 and CA1185 industrial strains and the CEN.PK113-7D laboratory strain. The industrial isolates produced remarkable high ethanol titres (>19%, v/v) and accumulated an increased content of sterols (2 to 5-fold), glycogen (2 to 4-fold) and trehalose (1.1-fold), relatively to laboratory strain. For laboratory and industrial strains, a sharp decrease in the viability and trehalose concentration was observed above 90 g l⁻¹ and 140 g l⁻¹ ethanol, respectively. PE-2 and CA1185 industrial strains presented important physiological differences relatively to CEN.PK113-7D strain and showed to be more prepared to cope with VHG stresses. The identification of a critical ethanol concentration above which viability and trehalose concentration decrease significantly is of great importance to guide VHG process engineering strategies. This study contributes to the improvement of VHG processes by identifying yeast isolates and gathering yeast physiological information during the intensified fermentation process, which, besides elucidating important differences between these industrial and laboratory strains, can drive further process optimization.

  14. Bioethanol production from cellulosic hydrolysates by engineered industrial Saccharomyces cerevisiae.

    PubMed

    Lee, Ye-Gi; Jin, Yong-Su; Cha, Young-Lok; Seo, Jin-Ho

    2017-03-01

    Even though industrial yeast strains exhibit numerous advantageous traits for the production of bioethanol, their genetic manipulation has been limited. This study demonstrates that an industrial polyploidy Saccharomyces cerevisiae JHS200 can be engineered through Cas9 (CRISPR associated protein 9)-based genome editing. Specifically, we generated auxotrophic mutants and introduced a xylose metabolic pathway into the auxotrophic mutants. As expected, the engineered strain (JX123) enhanced ethanol production from cellulosic hydrolysates as compared to other engineered haploid strains. However, the JX123 strain produced substantial amounts of xylitol as a by-product during xylose fermentation. Hypothesizing that the xylitol accumulation might be caused by intracellular redox imbalance from cofactor difference, the NADH oxidase from Lactococcus lactis was introduced into the JX123 strain. The resulting strain (JX123_noxE) not only produced more ethanol, but also produced xylitol less than the JX123 strain. These results suggest that industrial polyploidy yeast can be modified for producing biofuels and chemicals.

  15. Influence of Cloud-Radiative Processes on Predecessor Rain Events

    NASA Astrophysics Data System (ADS)

    Nava, Omar Angelo

    Predecessor rain events (PREs) are coherent mesoscale rainstorms that occur well in advance of recurving tropical cyclones (TCs) and have a high potential to cause flooding and adverse societal impacts. In 2007, a PRE associated with TC Erin produced record-breaking rainfall (> 350 mm) across southern Minnesota and Wisconsin, contributing to seven fatalities and over $170 million in property damage. A series of idealized numerical simulations is conducted using an aquaplanet version of the Weather Research and Forecasting model Advanced Research core (WRF-ARW) v.3.6 to examine the influence of cloud-radiative processes on the development of PREs. This study finds that cloud-radiative feedback (CRF), the interaction of hydrometeor cloud species with longwave (LW) and shortwave (SW) radiation, produces a more robust PRE structure with stronger convective activity and, ultimately, more precipitation. It is demonstrated that LW cooling associated with clouds outside of the PRE region induces a stronger horizontal pressure gradient that enhances low level con ergence and drives more vigorous ascent. Therefore, the primary radiation driver of PRE formation occurs outside of the PRE itself and is based on how the model responds radiatively to low clouds. In addition, the warming component of CRF enhances parcel buoyancy and reduces vertical stabilities within the PRE structure. In particular, the distribution of cloud ice produces a greater depth of in-cloud, primarily LW warming conducive to stronger convective processes. In contrast, SW CRF effects weaken PRE development through a combination of in-cloud cooling and low level cloud top warming, countering the LW CRF effects responsible for greater rainfall production. Moreover, PRE formation is found to be sensitive to the diurnal cycle, resulting in faster development at night and slower development during the day. A seasonal sensitivity also brings about weaker PRE intensification during the summer season; shorter

  16. Analysis of bioethanol samples through Inductively Coupled Plasma Mass Spectrometry with a total sample consumption system

    NASA Astrophysics Data System (ADS)

    Sánchez, Carlos; Lienemann, Charles-Philippe; Todolí, Jose-Luis

    2016-10-01

    Bioethanol real samples have been directly analyzed through ICP-MS by means of the so called High Temperature Torch Integrated Sample Introduction System (hTISIS). Because bioethanol samples may contain water, experiments have been carried out in order to determine the effect of ethanol concentration on the ICP-MS response. The ethanol content studied went from 0 to 50%, because higher alcohol concentrations led to carbon deposits on the ICP-MS interface. The spectrometer default spray chamber (double pass) equipped with a glass concentric pneumatic micronebulizer has been taken as the reference system. Two flow regimes have been evaluated: continuous sample aspiration at 25 μL min- 1 and 5 μL air-segmented sample injection. hTISIS temperature has been shown to be critical, in fact ICP-MS sensitivity increased with this variable up to 100-200 °C depending on the solution tested. Higher chamber temperatures led to either a drop in signal or a plateau. Compared with the reference system, the hTISIS improved the sensitivities by a factor included within the 4 to 8 range while average detection limits were 6 times lower for the latter device. Regarding the influence of the ethanol concentration on sensitivity, it has been observed that an increase in the temperature was not enough to eliminate the interferences. It was also necessary to modify the torch position with respect to the ICP-MS interface to overcome them. This fact was likely due to the different extent of ion plasma radial diffusion encountered as a function of the matrix when working at high chamber temperatures. When the torch was moved 1 mm plasma down axis, ethanolic and aqueous solutions provided statistically equal sensitivities. A preconcentration procedure has been applied in order to validate the methodology. It has been found that, under optimum conditions from the point of view of matrix effects, recoveries for spiked samples were close to 100%. Furthermore, analytical concentrations for real

  17. Thermochemical recovery of heat contained in flue gases by means of bioethanol conversion

    NASA Astrophysics Data System (ADS)

    Pashchenko, D. I.

    2013-06-01

    In the present paper consideration is being given to the use of bioethanol in the schemes of thermochemical recovery of heat contained in exit flue gases. Schematic diagrams illustrate the realization of thermochemical heat recovery by implementing ethanol steam conversion and conversion of ethanol by means of products of its complete combustion. The feasibility of attaining a high degree of recovery of heat contained in flue gases at the moderate temperature (up to 450°C) of combustion components is demonstrated in the example of the energy balance of the system for thermochemical heat recovery. The simplified thermodynamic analysis of the process of ethanol steam conversion was carried out in order to determine possible ranges of variation of process variables (temperature, pressure, composition) of a reaction mixture providing the efficient heat utilization. It was found that at the temperature above 600 K the degree of ethanol conversion is near unity. The equilibrium composition of products of reaction of ethanol steam conversion has been identified for different temperatures at which the process occurs at the ratio H2O/EtOH = 1 and at the pressure of 0.1 MPa. The obtained results of calculation agree well with the experimental data.

  18. Daphnia magna demonstrated sufficient sensitivity in techno-economic optimization of lignocellulose bioethanol production.

    PubMed

    Vochozka, Marek; Stehel, Vojtěch; Maroušková, Anna

    2017-07-01

    Notable progress has been achieved in the past two decades regarding production of different enzymatic mixtures for hydrolysis of the lignocellulose matrix. Nevertheless, the hydrolysing mixtures remain slow and require tempering, which results in high-energy demands and bad financial results. Use of acids or alkali at a very high temperature and pressure accelerates the process more than ten times wherein the energy requirements are approximately equal. However, these elevated reaction conditions might cause the breakdown of complex lignin formula into substances that have the potential to inhibit subsequent fermentation processes. Formation of these breakdown products may be prevented by selecting the optimum process parameters, but their acquisition requires either a large number of expensive analytical techniques or equally large amounts of slow fermentation tests. An inexpensive and time saving alternative that is based on the sensitivity of chosen organisms to these inhibitors was designed and financially assessed. It was confirmed that the method is technically feasible and economically viable with significant potential to reduce the bioethanol production cost.

  19. The Influence of Communication Processes on Group Outcomes: Antithesis and Thesis

    ERIC Educational Resources Information Center

    Hewes, Dean E.

    2009-01-01

    The influence of communication processes on group outcomes is discussed from two perspectives, one in which influence does not exist and one in which influence is central. Formal models for both perspectives are presented as a means of bracketing discussion of the role of communication processes in group outcomes. The implications of these models…

  20. The Influence of Knowledge about Causal Mechanisms on Compound Processing

    ERIC Educational Resources Information Center

    Garcia-Retamero, Rocio

    2007-01-01

    Empirical evidence has shown that several factors influence whether a compound is represented as several independent components or as a configuration. However, most of the previous research focused on data-driven factors (e.g., modality of the stimuli presented in the experimental task). In one experiment, I analyzed the influence of people's…

  1. Processes of Sibling Influence in Adolescence: Individual and Family Correlates

    ERIC Educational Resources Information Center

    Whiteman, Shawn D.; Christiansen, Abigail

    2008-01-01

    This study examined the nature and correlates of adolescents' perceptions of sibling influence. Participants included 2 siblings (firstborn age M = 17.34; second-born age M = 14.76 years) from 191 maritally intact families. Adolescents' perceptions of sibling influence were measured via coded responses to open-ended questions about whether their…

  2. Bioethanol/gasoline blends for fuelling conventional and hybrid scooter. Regulated and unregulated exhaust emissions

    NASA Astrophysics Data System (ADS)

    Costagliola, Maria Antonietta; Prati, Maria Vittoria; Murena, Fabio

    2016-05-01

    The aim of this experimental activity was to evaluate the influence of ethanol fuel on the pollutant emissions measured at the exhaust of a conventional and a hybrid scooter. Both scooters are 4-stroke, 125 cm3 of engine capacity and Euro 3 compliant. They were tested on chassis dynamometer for measuring gaseous emissions of CO, HC, NOx, CO2 and some toxic micro organic pollutants, such as benzene, 1,3-butadiene, formaldehyde and acetaldehyde. The fuel consumption was estimated throughout a carbon balance on the exhaust species. Moreover, total particles number with diameter between 20 nm up to 1 μm was measured. Worldwide and European test cycles were carried out with both scooters fuelled with gasoline and ethanol/gasoline blends (10/90, 20/80 and 30/70% vol). According to the experimental results relative to both scooter technologies, the addiction of ethanol in gasoline reduces CO and particles number emissions. The combustion of conventional scooter becomes unstable when a percentage of 30%v of bioethanol is fed; as consequence a strong increasing of hydrocarbon is monitored, including carcinogenic species. The negative effects of ethanol fuel are related to the increasing of fuel consumption due to the less carbon content for volume unit and to the increasing of formaldehyde and acetaldehyde due to the higher oxygen availability. Almost 70% of Ozone Formation Potential is covered by alkenes and aromatics.

  3. Bioethanol production from raw sugar beet cossettes in horizontal rotating tubular bioreactor.

    PubMed

    Pavlečić, Mladen; Rezić, Tonči; Šantek, Mirela Ivančić; Horvat, Predrag; Šantek, Božidar

    2017-08-02

    Fossil fuels are still major energy sources, but the search for renewable energy sources has been encouraged. Bioethanol has been recognized as an alternative to fossil fuels and nowadays it represents more than 90% of the global biofuel production. Bioethanol production from raw sugar beet cossettes as a semi-solid substrate was studied. The study was carried out in the horizontal rotating tubular bioreactor (HRTB) with Saccharomyces cerevisiae as a microbial production strain. The impact of different combinations of HRTB operational parameters such as, rotation speed (5-15 min(-1)), rotation type [constant or interval (3-15 min h(-1))] and working volume (ratio V W/V T = 0.2-0.7) on the bioethanol production was examined. In this study, the highest bioprocess efficiency parameters ([Formula: see text] = 0.47 g g(-1), E = 87.36% and Pr = 0.618 g L(-1) h(-1)) were observed at 0.20 V W/V T, interval rotation of 12 min h(-1) and rotation speed of 15 min(-1). It has to be pointed out that bioethanol production efficiency in the HRTB was on the similar level as observed by bioethanol production from the raw sugar beet juice. Naturally present microorganisms of sugar beet could have a significant impact on bioethanol production. Higher yeast inoculation rate could reduce contaminant activities and, consequently, the bioethanol production efficiency would be improved.

  4. Organosolvent pretreatment and enzymatic hydrolysis of rice straw for the production of bioethanol.

    PubMed

    Sindhu, Raveendran; Binod, Parameswaran; Janu, Kanakambaran Usha; Sukumaran, Rajeev K; Pandey, Ashok

    2012-02-01

    The present study investigates the operational conditions for organosolvent pretreatment and hydrolysis of rice straw. Among the different organic acids and organic solvents tested, acetone was found to be most effective based on the fermentable sugar yield. Optimization of process parameters for acetone pretreatment were carried out. The structural changes before and after pretreatment were investigated by scanning electron microscopy, X-ray diffraction and Fourier transform infrared (FTIR) analysis. The X-ray diffraction profile showed that the degree of crystallinity was higher for acetone pretreated biomass than that of the native. FTIR spectrum also exhibited significant difference between the native and pretreated samples. Under optimum pretreatment conditions 0.458 g of reducing sugar was produced per gram of pretreated biomass with a fermentation efficiency of 39%. Optimization of process parameters for hydrolysis such as biomass loading, enzyme loading, surfactant concentration and incubation time was done using Box-Benhken design. The results indicate that acetone pretreated rice straw can be used as a good feed stock for bioethanol production.

  5. Cell-wall structural changes in wheat straw pretreated for bioethanol production

    PubMed Central

    Kristensen, Jan B; Thygesen, Lisbeth G; Felby, Claus; Jørgensen, Henning; Elder, Thomas

    2008-01-01

    Background Pretreatment is an essential step in the enzymatic hydrolysis of biomass and subsequent production of bioethanol. Recent results indicate that only a mild pretreatment is necessary in an industrial, economically feasible system. The Integrated Biomass Utilisation System hydrothermal pretreatment process has previously been shown to be effective in preparing wheat straw for these processes without the application of additional chemicals. In the current work, the effect of the pretreatment on the straw cell-wall matrix and its components are characterised microscopically (atomic force microscopy and scanning electron microscopy) and spectroscopically (attenuated total reflectance Fourier transform infrared spectroscopy) in order to understand this increase in digestibility. Results The hydrothermal pretreatment does not degrade the fibrillar structure of cellulose but causes profound lignin re-localisation. Results from the current work indicate that wax has been removed and hemicellulose has been partially removed. Similar changes were found in wheat straw pretreated by steam explosion. Conclusion Results indicate that hydrothermal pretreatment increases the digestibility by increasing the accessibility of the cellulose through a re-localisation of lignin and a partial removal of hemicellulose, rather than by disruption of the cell wall. PMID:18471316

  6. Steam pretreatment of Saccharum officinarum L. bagasse by adding of impregnating agents for advanced bioethanol production.

    PubMed

    Verardi, A; Blasi, A; De Bari, I; Calabrò, V

    2016-12-01

    The main byproduct of the sugarcane industry, Saccharum officinarum L. bagasse (sugarcane bagasse, SCB), is widely used as lignocellulose biomass for bio-ethanol (EtOH) production. In this research study, SCB was pretreated by steam explosion (SE) method using two different impregnating agents: sulfur dioxide (SD) and hydrogen peroxide (HP). As matter of fact, the use of impregnating agents improves the performance of SE method, increasing the concentrations of fermentable sugars after enzymatic saccharification, and decreasing the inhibitor compounds produced during the steam pretreatment step. The aim of this study was to investigate and compare the use of the two impregnating agents in various SE-conditions in order to optimize pretreatment parameters. For every pretreatment condition, it has been evaluated: concentration of fermentable sugars, glucose and xylose yields, and the effects of the inhibitor compounds on enzymatic hydrolysis step. The obtained results allow to improve the efficiency of the whole process of bio-EtOH synthesis enhancing the amount of fermentable sugars produced and the eco-sustainability of the whole process. Indeed, the optimization of steam pretreatment leads to a reduction of energy requirements and to a lower environmental impact.

  7. Vitamin B1-catalyzed acetoin formation from acetaldehyde: a key step for upgrading bioethanol to bulk C₄ chemicals.

    PubMed

    Lu, Ting; Li, Xiukai; Gu, Liuqun; Zhang, Yugen

    2014-09-01

    The production of bulk chemicals and fuels from renewable biobased feedstocks is of significant importance for the sustainability of human society. The production of ethanol from biomass has dramatically increased and bioethanol also holds considerable potential as a versatile building block for the chemical industry. Herein, we report a highly selective process for the conversion of ethanol to C4 bulk chemicals, such as 2,3-butanediol and butene, via a vitamin B1 (thiamine)-derived N-heterocyclic carbene (NHC)-catalyzed acetoin condensation as the key step to assemble two C2 acetaldehydes into a C4 product. The environmentally benign and cheap natural catalyst vitamin B1 demonstrates high selectivity (99%), high efficiency (97% yield), and high tolerance toward ethanol and water impurities in the acetoin reaction. The results enable a novel and efficient process for ethanol upgrading. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. Bioethanol from poplar clone Imola: an environmentally viable alternative to fossil fuel?

    PubMed

    Guo, Miao; Li, Changsheng; Facciotto, Gianni; Bergante, Sara; Bhatia, Rakesh; Comolli, Roberto; Ferré, Chiara; Murphy, Richard

    2015-01-01

    Environmental issues, e.g. climate change, fossil resource depletion have triggered ambitious national/regional policies to develop biofuel and bioenergy roles within the overall energy portfolio to achieve decarbonising the global economy and increase energy security. With the 10 % binding target for the transport sector, the Renewable Energy Directive confirms the EU's commitment to renewable transport fuels especially advanced biofuels. Imola is an elite poplar clone crossed from Populus deltoides Bartr. and Populus nigra L. by Research Units for Intensive Wood Production, Agriculture Research Council in Italy. This study examines its suitability for plantation cultivation under short or very short rotation coppice regimes as a potential lignocellulosic feedstock for the production of ethanol as a transport biofuel. A life cycle assessment (LCA) approach was used to model the cradle-to-gate environmental profile of Imola-derived biofuel benchmarked against conventional fossil gasoline. Specific attention was given to analysing the agroecosystem fluxes of carbon and nitrogen occurring in the cultivation of the Imola biomass in the biofuel life cycle using a process-oriented biogeochemistry model (DeNitrification-DeComposition) specifically modified for application to 2G perennial bioenergy crops and carbon and nitrogen cycling. Our results demonstrate that carbon and nitrogen cycling in perennial crop-soil ecosystems such as this example can be expected to have significant effects on the overall environmental profiles of 2G biofuels. In particular, soil carbon accumulation in perennial biomass plantations is likely to be a significant component in the overall greenhouse gas balance of future biofuel and other biorefinery products and warrants ongoing research and data collection for LCA models. We conclude that bioethanol produced from Imola represents a promising alternative transport fuel offering some savings ranging from 35 to 100 % over petrol in global

  9. Cost Effective Bioethanol via Acid Pretreatment of Corn Stover, Saccharification, and Conversion via a Novel Fermentation Organism: Cooperative Research and Development Final Report, CRADA Number: CRD-12-485

    SciTech Connect

    Dowe, N.

    2014-05-01

    This research program will convert acid pretreated corn stover to sugars at the National Renewable Energy Laboratory (NREL) and then transfer these sugars to Honda R&D and its partner the Green Earth Institute (GEI) for conversion to ethanol via a novel fermentation organism. In phase one, NREL will adapt its pretreatment and saccharification process to the unique attributes of this organism, and Honda R&D/GEI will increase the sugar conversion rate as well as the yield and titer of the resulting ethanol. In later phases, NREL, Honda R&D, and GEI will work together at NREL to optimize and scale-up to pilot-scale the Honda R&D/GEI bioethanol production process. The final stage will be to undertake a pilot-scale test at NREL of the optimized bioethanol conversion process.

  10. An evaluation of cassava, sweet potato and field corn as potential carbohydrate sources for bioethanol production in Alabama and Maryland

    USDA-ARS?s Scientific Manuscript database

    The recent emphasis on corn production to meet the increasing demand for bioethanol has resulted in trepidation regarding the sustainability of the global food supply. To assess the potential of alternative crops as sources of bioethanol production, we grew sweet potato (Ipomoea batatas) and cassav...

  11. Second generation bioethanol potential from selected Malaysia's biodiversity biomasses: A review.

    PubMed

    Aditiya, H B; Chong, W T; Mahlia, T M I; Sebayang, A H; Berawi, M A; Nur, Hadi

    2016-01-01

    Rising global temperature, worsening air quality and drastic declining of fossil fuel reserve are the inevitable phenomena from the disorganized energy management. Bioethanol is believed to clear out the effects as being an energy-derivable product sourced from renewable organic sources. Second generation bioethanol interests many researches from its unique source of inedible biomass, and this paper presents the potential of several selected biomasses from Malaysia case. As one of countries with rich biodiversity, Malaysia holds enormous potential in second generation bioethanol production from its various agricultural and forestry biomasses, which are the source of lignocellulosic and starch compounds. This paper reviews potentials of biomasses and potential ethanol yield from oil palm, paddy (rice), pineapple, banana and durian, as the common agricultural waste in the country but uncommon to be served as bioethanol feedstock, by calculating the theoretical conversion of cellulose, hemicellulose and starch components of the biomasses into bioethanol. Moreover, the potential of the biomasses as feedstock are discussed based on several reported works.

  12. The Influence of Contrast on Coherent Motion Processing in Dyslexia

    ERIC Educational Resources Information Center

    Conlon, Elizabeth G.; Lilleskaret, Gry; Wright, Craig M.; Power, Garry F.

    2012-01-01

    The aim of the experiments was to investigate how manipulating the contrast of the signal and noise dots in a random dot kinematogram (RDK), influenced on motion coherence thresholds in adults with dyslexia. In the first of two experiments, coherent motion thresholds were measured when the contrasts of the signal and noise dots in an RDK were…

  13. The Influence of Contrast on Coherent Motion Processing in Dyslexia

    ERIC Educational Resources Information Center

    Conlon, Elizabeth G.; Lilleskaret, Gry; Wright, Craig M.; Power, Garry F.

    2012-01-01

    The aim of the experiments was to investigate how manipulating the contrast of the signal and noise dots in a random dot kinematogram (RDK), influenced on motion coherence thresholds in adults with dyslexia. In the first of two experiments, coherent motion thresholds were measured when the contrasts of the signal and noise dots in an RDK were…

  14. Leader Influences on Training Effectiveness: Motivation and Outcome Expectation Processes

    ERIC Educational Resources Information Center

    Scaduto, Anne; Lindsay, Douglas; Chiaburu, Dan S.

    2008-01-01

    Training effectiveness is a function of trainee characteristics, training design and contextual factors. Social exchanges in the work environment have received less attention compared with other training effectiveness predictors. We focus on the extent to which leaders (through their relationships and exchanges with followers) influence skill…

  15. Sex Differences in Influenceability: Toward Specifying the Underlying Processes.

    ERIC Educational Resources Information Center

    Cacioppo, John T.; Petty, Richard E.

    Sex differences in influencability have emerged when discrepant advocacies were accompanied by greater expertise in the subject matter by men or women. Two types of stimuli, one about which men relative to women had high prior knowledge (football tackles) and one about which women had higher prior knowledge (women's fashions), were selected. Men…

  16. Optimization of alkaline pretreatment of coffee pulp for production of bioethanol.

    PubMed

    Menezes, Evandro G T; do Carmo, Juliana R; Alves, José Guilherme L F; Menezes, Aline G T; Guimarães, Isabela C; Queiroz, Fabiana; Pimenta, Carlos J

    2014-01-01

    The use of lignocellulosic raw materials in bioethanol production has been intensively investigated in recent years. However, for efficient conversion to ethanol, many pretreatment steps are required prior to hydrolysis and fermentation. Coffee stands out as the most important agricultural product in Brazil and wastes such as pulp and coffee husk are generated during the wet and dry processing to obtain green grains, respectively. This work focused on the optimization of alkaline pretreatment of coffee pulp with the aim of making its use in the alcoholic fermentation. A central composite rotatable design was used with three independent variables: sodium hydroxide and calcium hydroxide concentrations and alkaline pretreatment time, totaling 17 experiments. After alkaline pretreatment the concentration of cellulose, hemicellulose, and lignin remaining in the material, the subsequent hydrolysis of the cellulose component and its fermentation of substrate were evaluated. The results indicated that pretreatment using 4% (w/v) sodium hydroxide solution, with no calcium hydroxide, and 25 min treatment time gave the best results (69.18% cellulose remaining, 44.15% hemicelluloses remaining, 25.19% lignin remaining, 38.13 g/L of reducing sugars, and 27.02 g/L of glucose) and produced 13.66 g/L of ethanol with a yield of 0.4 g ethanol/g glucose. © 2013 American Institute of Chemical Engineers.

  17. Bioethanol production from leafy biomass of mango (Mangifera indica) involving naturally isolated and recombinant enzymes.

    PubMed

    Das, Saprativ P; Ravindran, Rajeev; Deka, Deepmoni; Jawed, Mohammad; Das, Debasish; Goyal, Arun

    2013-01-01

    The present study describes the usage of dried leafy biomass of mango (Mangifera indica) containing 26.3% (w/w) cellulose, 54.4% (w/w) hemicellulose, and 16.9% (w/w) lignin, as a substrate for bioethanol production from Zymomonas mobilis and Candida shehatae. The substrate was subjected to two different pretreatment strategies, namely, wet oxidation and an organosolv process. An ethanol concentration (1.21 g/L) was obtained with Z. mobilis in a shake-flask simultaneous saccharification and fermentation (SSF) trial using 1% (w/v) wet oxidation pretreated mango leaves along with mixed enzymatic consortium of Bacillus subtilis cellulase and recombinant hemicellulase (GH43), whereas C. shehatae gave a slightly higher (8%) ethanol titer of 1.31 g/L. Employing 1% (w/v) organosolv pretreated mango leaves and using Z. mobilis and C. shehatae separately in the SSF, the ethanol titers of 1.33 g/L and 1.52 g/L, respectively, were obtained. The SSF experiments performed with 5% (w/v) organosolv-pretreated substrate along with C. shehatae as fermentative organism gave a significantly enhanced ethanol titer value of 8.11 g/L using the shake flask and 12.33 g/L at the bioreactor level. From the bioreactor, 94.4% (v/v) ethanol was recovered by rotary evaporator with 21% purification efficiency.

  18. Efficiency of Blenke cascade system for continuous bio-ethanol fermentation.

    PubMed

    Ntihuga, Jean Nepomuscene; Senn, Thomas; Gschwind, Peter; Kohlus, Reinhard

    2012-11-01

    A gas lift-system with inserts (so-called Blenke cascade system) for continuous bio-ethanol fermentation was constructed. Gas introduced at the bottom of the column created toroidal vortices in the fluid cells between inserts, enhancing mixing and improving residence time behavior without stirring equipment being necessary. The parameters mash type, start-up strategy, yeast-recycle model and yeast separation were studied concerning the efficiency of the ethanol production. The best results obtained were for a filtered mash, a double saccharification principle (DSP), a batch start-up strategy, an activation-recycle model and a lamella settler connected in series with a small conventional gravitational settler for yeast cells separation. Using this system, the fermentation residence time was τ=4-5.5h, depending on substrate type. Eighty five percent of the yeast cells could be separated. High volumetric ethanol productivity (Q(p)=20.43g/Lh) and yield E(y)=98% were achieved. Continuous fermentation, yeast recycling and sedimentation were contamination-free processes.

  19. Development of a Solid-State Fermentation System for Producing Bioethanol from Food Waste

    NASA Astrophysics Data System (ADS)

    Honda, Hiroaki; Ohnishi, Akihiro; Fujimoto, Naoshi; Suzuki, Masaharu

    Liquid fermentation is the a conventional method of producing bioethanol. However, this method results in the formation of high concentrations waste after distillation and futher treatment requires more energy and is costly(large amounts of costly energy).Saccharification of dried raw garbage was tested for 12 types of Koji starters under the following optimum culture conditions: temperature of 30°C and initial moisture content of 50%.Among all the types, Aspergillus oryzae KBN650 had the highest saccharifying power. The ethanol-producing ability of the raw garbage was investigated for 72 strains of yeast, of which Saccharomyces cerevisiae A30 had the highest ethanol production(yield)under the following optimum conditions: 1 :1 ratio of dried garbage and saccharified garbage by weight, and initial moisture content of 60%. Thus, the solid-state fermentation system consisted of the following 4 processes: moisture control, saccharification, ethanol production and distillation. This system produced 0.6kg of ethanol from 9.6kg of garbage. Moreover the ethanol yield from all sugars was calculated to be 0.37.

  20. Bioethanol Production By Utilizing Cassava Peels Waste Through Enzymatic And Microbiological Hydrolysis

    NASA Astrophysics Data System (ADS)

    Witantri, R. G.; Purwoko, T.; Sunarto; Mahajoeno, E.

    2017-07-01

    Cassava peels waste contains, cellulose which is quite high at 43.626%, this is a potential candidate as a raw for bioethanol production. The purpose of this study was to determine the performance of the enzymatic hydrolysis, microbiological (Effective microbe) and fermentation in cassava peel waste is known from the results of quantitative measurement of multiple ethanol parameters (DNS Test, pH, ethanol concentration). This research was carried out in stages, the first stage is hydrolysis with completely randomized design with single factor variation of the catalyst, consisting of three levels ie cellulase enzymes, multienzyme and effective microbial EM4. The second stage is fermentation with factorial randomized block design, consisting of three groups of variations of catalyst, and has two factors: variations of fermipan levels 1, 2, 3% and the duration of fermentation, 2,4,6 days. The parameters in the test is a reducing sugar, pH and concentration of ethanol. The results showed that variation of hydrolysis treatment, fermentation time, and fermipan levels has real effect on the fermentation process. On average the highest ethanol content obtained from the treatment with multienzyme addition, with the addition of 2% fermipan levels and on the 2nd day of fermentation that is equal to 3.76%.

  1. Sun-to-Wheels Exergy Efficiencies for Bio-Ethanol and Photovoltaics.

    PubMed

    Williams, Eric; Sekar, Ashok; Matteson, Schuyler; Rittmann, Bruce E

    2015-06-02

    The two main paths to power vehicles with sunlight are to use photosynthesis to grow biomass, converting to a liquid fuel for an internal combustion engine or to generate photovoltaic electricity that powers the battery of an electric vehicle. While the environmental attributes of these two paths have been much analyzed, prior studies consider the current state of technology. Technologies for biofuel and photovoltaic paths are evolving; it is critical to consider how progress might improve environmental performance. We address this challenge by assessing the current and maximum theoretical exergy efficiencies of bioethanol and photovoltaic sun-to-wheels process chains. The maximum theoretical efficiency is an upper bound stipulated by physical laws. The current net efficiency to produce motive power from silicon photovoltaic modules is estimated at 5.4%, much higher than 0.03% efficiency for corn-based ethanol. Flat-plate photovoltaic panels also have a much higher theoretical maximum efficiency than a C4 crop plant, 48% versus 0.19%. Photovoltaic-based power will always be vastly more efficient than a terrestrial crop biofuel. Providing all mobility in the U.S. via crop biofuels would require 130% of arable land with current technology and 20% in the thermodynamic limit. Comparable values for photovoltaic-based power are 0.7% and 0.081%, respectively.

  2. Alternative antimicrobial compounds to control potential Lactobacillus contamination in bioethanol fermentations.

    PubMed

    Limayem, Alya; Hanning, Irene B; Muthaiyan, Arunachalam; Illeghems, Koen; Kim, Jin-Woo; Crandall, Philip G; O'Bryan, Corliss A; Ricke, Steven C

    2011-01-01

    Antibiotics are commonly used to control microbial contaminants in yeast-based bioethanol fermentation. Given the increase in antibiotic-resistant bacteria, alternative natural antimicrobials were evaluated against the potential contaminant, Lactobacillus. The effects of nisin, ϵ-polylysine, chitosan (CS) and lysozyme were screened against 5 Lactobacillus strains. A standard broth- microdilution method was used in 96-well plates to assess the minimal inhibitory concentration (MIC). L. delbrueckii subsp lactis ATCC479 exhibited maximal MICs with CS, ϵ-polylysine and nisin (1.87, 0.3125 and 0.05 mg/mL, respectively). Nisin reduced most Lactobacillus strains by 6 log CFU/mL after 48 hours with the exception of L. casei. Synergism occurred when ethylenediaminetetraacetic acid (EDTA) was added with nisin. An MIC of 0.4 mg/mL of nisin combined with the EDTA at an MIC of 1 mg/ml markedly suppressed L .casei by 6 log CFU/mL. In conclusion, alternative antimicrobials proved to be a potential candidate for controlling bacterial contamination in the fermentation process. Synergistic effect of nisin with EDTA successfully inhibited the nisin-resistant contaminant, L. casei.

  3. Structural evaluation and bioethanol production by simultaneous saccharification and fermentation with biodegraded triploid poplar

    PubMed Central

    2013-01-01

    Background Pretreatment is a key step to decrease the recalcitrance of lignocelluloses and then increase the digestibility of cellulose in second-generation bioethanol production. In this study, wood chips from triploid poplar were biopretreated with white rot fungus Trametes velutina D10149. The effects of incubation duration on delignification efficiency and structural modification of cellulose were comparably studied, as well as the digestibility of cellulose by simultaneous saccharification and fermentation (SSF). Results Although microbial pretreatments did not significantly introduce lignin degradation, the data from SSF exhibited higher cellulose conversion (21-75% for biopretreated samples for 4–16 weeks) as compared to the untreated poplar (18%). In spite of the essential maintain of crystallinity, the modification of lignin structure during fungal treatment undoubtedly played a key role in improving cellulose bioconversion rates. Finally, the ethanol concentration of 5.16 g/L was detected in the fermentation broth from the cellulosic sample biodegraded for 16 weeks after 24 h SSF, achieving 34.8% cellulose utilization in poplar. Conclusion The potential fungal pretreatment with Trametes velutina D10149 was firstly explored in this study. It is found that the biopretreatment process had a significant effect on the digestibility of substrate probably due to the removal and unit variation of lignin, since the crystallinities of substrates were rarely changed. Additional investigation is still required especially to improve the selectivity for lignin degradation and optimize the digestibility of cellulose. PMID:23517540

  4. Cellulolytic enzyme production and enzymatic hydrolysis for second-generation bioethanol production.

    PubMed

    Wang, Mingyu; Li, Zhonghai; Fang, Xu; Wang, Lushan; Qu, Yinbo

    2012-01-01

    Second-generation bioethanol made from lignocellulosic biomass is considered one of the most promising biofuels. However, the enzymatic hydrolysis of the cellulose component to liberate glucose for ethanol fermentation is one of the major barriers for the process to be economically competitive because of the recalcitrance of feedstock. In this chapter, the progress on the understanding of the mechanisms of lignocellulose degradation, as well as the identification and optimization of fungal cellulases, cellulolytic strains, and cellulase production is reviewed. The physiologic functions and enzymatic mechanisms of two groups of enzymes involved in lignocellulose degradation, cellulases and hemicellulases, are discussed, and the synergism of the cellulase components during lignocellulose degradation is addressed. Furthermore, the methods for screening filamentous fungal strains capable of degrading lignocellulose are evaluated and the production of cellulases by these fungal strains is discussed. Aside from traditional mutagenesis for improving the secretion level and enzymatic activities of cellulases from filamentous fungal species, genetic engineering of strains and protein engineering on cellulase molecules are also highlighted.

  5. Flocculation causes inhibitor tolerance in Saccharomyces cerevisiae for second-generation bioethanol production.

    PubMed

    Westman, Johan O; Mapelli, Valeria; Taherzadeh, Mohammad J; Franzén, Carl Johan

    2014-11-01

    Yeast has long been considered the microorganism of choice for second-generation bioethanol production due to its fermentative capacity and ethanol tolerance. However, tolerance toward inhibitors derived from lignocellulosic materials is still an issue. Flocculating yeast strains often perform relatively well in inhibitory media, but inhibitor tolerance has never been clearly linked to the actual flocculation ability per se. In this study, variants of the flocculation gene FLO1 were transformed into the genome of the nonflocculating laboratory yeast strain Saccharomyces cerevisiae CEN.PK 113-7D. Three mutants with distinct differences in flocculation properties were isolated and characterized. The degree of flocculation and hydrophobicity of the cells were correlated to the length of the gene variant. The effect of different strength of flocculation on the fermentation performance of the strains was studied in defined medium with or without fermentation inhibitors, as well as in media based on dilute acid spruce hydrolysate. Strong flocculation aided against the readily convertible inhibitor furfural but not against less convertible inhibitors such as carboxylic acids. During fermentation of dilute acid spruce hydrolysate, the most strongly flocculating mutant with dense cell flocs showed significantly faster sugar consumption. The modified strain with the weakest flocculation showed a hexose consumption profile similar to the untransformed strain. These findings may explain why flocculation has evolved as a stress response and can find application in fermentation-based biorefinery processes on lignocellulosic raw materials. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

  6. Changes of trehalose content and expression of relative genes during the bioethanol fermentation by Saccharomyces cerevisiae.

    PubMed

    Yi, Chenfeng; Wang, Fenglian; Dong, Shijun; Li, Hao

    2016-10-01

    Traditionally, trehalose is considered as a protectant to improve the ethanol tolerance of Saccharomyces cerevisiae. In this study, to clarify the changes and roles of trehalose during the bioethanol fermentation, trehalose content and expression of related genes at lag, exponential, and stationary phases (i.e., 2, 8, and 16 h of batch fermentation process) were determined. Although yeast cells at exponential and stationary phase had higher trehalose content than cells at lag phase (P < 0.01), there was no significant difference in trehalose content between exponential and stationary phases (P > 0.05). Moreover, expression of the trehalose degradation-related genes NTH1 and NTH2 decreased at exponential phase in comparison with that at lag phase; compared with cells at lag phase, cells at stationary phase had higher expression of TPS1, ATH1, NTH1, and NTH2 but lower expression of TPS2. During the lag-exponential phase transition, downregulation of NTH1 and NTH2 promoted accumulation of trehalose, and to some extent, trehalose might confer ethanol tolerance to S. cerevisiae before stationary phase. During the exponential-stationary phase transition, upregulation of TPS1 contributed to accumulation of trehalose, and Tps1 protein might be indispensable in yeast cells to withstand ethanol stress at the stationary phase. Moreover, trehalose would be degraded to supply carbon source at stationary phase.

  7. Current Trends in Bioethanol Production by Saccharomyces cerevisiae: Substrate, Inhibitor Reduction, Growth Variables, Coculture, and Immobilization.

    PubMed

    Tesfaw, Asmamaw; Assefa, Fassil

    2014-01-01

    Bioethanol is one of the most commonly used biofuels in transportation sector to reduce greenhouse gases. S. cerevisiae is the most employed yeast for ethanol production at industrial level though ethanol is produced by an array of other yeasts, bacteria, and fungi. This paper reviews the current and nonmolecular trends in ethanol production using S. cerevisiae. Ethanol has been produced from wide range of substrates such as molasses, starch based substrate, sweet sorghum cane extract, lignocellulose, and other wastes. The inhibitors in lignocellulosic hydrolysates can be reduced by repeated sequential fermentation, treatment with reducing agents and activated charcoal, overliming, anion exchanger, evaporation, enzymatic treatment with peroxidase and laccase, in situ detoxification by fermenting microbes, and different extraction methods. Coculturing S. cerevisiae with other yeasts or microbes is targeted to optimize ethanol production, shorten fermentation time, and reduce process cost. Immobilization of yeast cells has been considered as potential alternative for enhancing ethanol productivity, because immobilizing yeasts reduce risk of contamination, make the separation of cell mass from the bulk liquid easy, retain stability of cell activities, minimize production costs, enable biocatalyst recycling, reduce fermentation time, and protect the cells from inhibitors. The effects of growth variables of the yeast and supplementation of external nitrogen sources on ethanol optimization are also reviewed.

  8. Current Trends in Bioethanol Production by Saccharomyces cerevisiae: Substrate, Inhibitor Reduction, Growth Variables, Coculture, and Immobilization

    PubMed Central

    Assefa, Fassil

    2014-01-01

    Bioethanol is one of the most commonly used biofuels in transportation sector to reduce greenhouse gases. S. cerevisiae is the most employed yeast for ethanol production at industrial level though ethanol is produced by an array of other yeasts, bacteria, and fungi. This paper reviews the current and nonmolecular trends in ethanol production using S. cerevisiae. Ethanol has been produced from wide range of substrates such as molasses, starch based substrate, sweet sorghum cane extract, lignocellulose, and other wastes. The inhibitors in lignocellulosic hydrolysates can be reduced by repeated sequential fermentation, treatment with reducing agents and activated charcoal, overliming, anion exchanger, evaporation, enzymatic treatment with peroxidase and laccase, in situ detoxification by fermenting microbes, and different extraction methods. Coculturing S. cerevisiae with other yeasts or microbes is targeted to optimize ethanol production, shorten fermentation time, and reduce process cost. Immobilization of yeast cells has been considered as potential alternative for enhancing ethanol productivity, because immobilizing yeasts reduce risk of contamination, make the separation of cell mass from the bulk liquid easy, retain stability of cell activities, minimize production costs, enable biocatalyst recycling, reduce fermentation time, and protect the cells from inhibitors. The effects of growth variables of the yeast and supplementation of external nitrogen sources on ethanol optimization are also reviewed. PMID:27379305

  9. Subcritical and supercritical technology for the production of second generation bioethanol.

    PubMed

    Rostagno, Mauricio A; Prado, Juliana M; Mudhoo, Ackmez; Santos, Diego T; Forster-Carneiro, Tânia; Meireles, M Angela A

    2015-01-01

    There is increased interest in reducing our reliance on fossil fuels and increasing the share of renewable raw materials in our energy supply chain due to environmental and economic concerns. Ethanol is emerging as a potential alternative to liquid fuels due to its eco-friendly characteristics and relatively low production costs. As ethanol is currently produced from commodities also used for human and animal consumption, there is an urgent need of identifying renewable raw materials that do not pose a competitive problem. Lignocellulosic agricultural residues are an ideal choice since they can be effectively hydrolyzed to fermentable sugars and integrated in the context of a biorefinery without competing with the food supply chain. However, the conventional hydrolysis methods still have major issues that need to be addressed. These issues are related to the processing rate and generation of fermentation inhibitors, which can compromise the quality of the product and the cost of the process. As the knowledge of the processes taking place during hydrolysis of agricultural residues is increasing, new techniques are being exploited to overcome these drawbacks. This review gives an overview of the state-of-the-art of hydrolysis with subcritical and supercritical water in the context of reusing agricultural residues for the production of suitable substrates to be processed during the fermentative production of bioethanol. Presently, subcritical and/or supercritical water hydrolysis has been found to yield low sugar contents mainly due to concurrent competing degradation of sugars during the hydrothermal processes. In this line of thinking, the present review also revisits the recent applications and advances to provide an insight of future research trends to optimize on the subcritical and supercritical process kinetics.

  10. Recovery of Glucose from Residual Starch of Sago Hampas for Bioethanol Production

    PubMed Central

    Awg-Adeni, D. S.; Bujang, K. B.; Hassan, M. A.; Abd-Aziz, S.

    2013-01-01

    Lower concentration of glucose was often obtained from enzymatic hydrolysis process of agricultural residue due to complexity of the biomass structure and properties. High substrate load feed into the hydrolysis system might solve this problem but has several other drawbacks such as low rate of reaction. In the present study, we have attempted to enhance glucose recovery from agricultural waste, namely, “sago hampas,” through three cycles of enzymatic hydrolysis process. The substrate load at 7% (w/v) was seen to be suitable for the hydrolysis process with respect to the gelatinization reaction as well as sufficient mixture of the suspension for saccharification process. However, this study was focused on hydrolyzing starch of sago hampas, and thus to enhance concentration of glucose from 7% substrate load would be impossible. Thus, an alternative method termed as cycles I, II, and III which involved reusing the hydrolysate for subsequent enzymatic hydrolysis process was introduced. Greater improvement of glucose concentration (138.45 g/L) and better conversion yield (52.72%) were achieved with the completion of three cycles of hydrolysis. In comparison, cycle I and cycle II had glucose concentration of 27.79 g/L and 73.00 g/L, respectively. The glucose obtained was subsequently tested as substrate for bioethanol production using commercial baker's yeast. The fermentation process produced 40.30 g/L of ethanol after 16 h, which was equivalent to 93.29% of theoretical yield based on total glucose existing in fermentation media. PMID:23509813

  11. Beyond Homophily: A Decade of Advances in Understanding Peer Influence Processes

    ERIC Educational Resources Information Center

    Brechwald, Whitney A.; Prinstein, Mitchell J.

    2011-01-01

    This article reviews empirical and theoretical contributions to a multidisciplinary understanding of peer influence processes in adolescence over the past decade. Five themes of peer influence research from this decade were identified, including a broadening of the range of behaviors for which peer influence occurs, distinguishing the sources of…

  12. Bench-scale bioethanol production from eucalyptus by high solid saccharification and glucose/xylose fermentation method.

    PubMed

    Fujii, Tatsuya; Murakami, Katsuji; Endo, Takashi; Fujimoto, Shinji; Minowa, Tomoaki; Matsushika, Akinori; Yano, Shinichi; Sawayama, Shigeki

    2014-04-01

    In the bioethanol production process, high solid saccharification and glucose/xylose co-fermentation are important technologies for obtaining increased ethanol concentrations; however, bench-scale studies using combinations of these methods are limited. In this study, we hydrolyzed high solid concentration of milled eucalyptus using commercial enzymes and obtained 138.4 g/L total monomeric sugar concentration. These sugars were fermented to 53.5 g/L of ethanol by a xylose-utilizing recombinant Saccharomyces cerevisiae strain, MA-R4. These experiments were performed in bench scale (using 50 L scale solid mixer and 70 L scale fermenter). The results obtained in this study were comparable to our previous results in laboratory scale, indicating that we successfully achieved an efficient high solid saccharification and glucose/xylose co-fermentation system in bench scale.

  13. Evaluation of ligninolytic enzymes, ultrasonication and liquid hot water as pretreatments for bioethanol production from cotton gin trash.

    PubMed

    Plácido, Jersson; Imam, Tahmina; Capareda, Sergio

    2013-07-01

    Cotton gin trash (CGT) is a ubiquitous cotton-production-waste resource which can be used for ethanol production. In this research, seven combinations of three pretreatments; ultrasonication, liquid hot water and ligninolytic enzymes were evaluated on CGT to select the best pretreatments combination that increased the cellulose conversion and the ethanol yield in the saccharification and fermentation processes, respectively. The structural changes in the cellulose, hemicellulose and lignin from CGT were followed using FT-IR after each pretreatment. All the pretreatment combinations modified the CGT's structure and composition compared with the unpretreated CGT, and the majority of them improved release of sugars originally present in the CGT. The best results were achieved by the sequential combination of ultrasonication, hot water, and ligninolytic enzymes with an improvement of 10% in the ethanol yield and cellulose conversion compared to the other pretreatments. These results are a contribution to develop a feasible bioethanol production from CGT.

  14. Sensitivities of a Standard Test Method for the Determination of the pHe of Bioethanol and Suggestions for Improvement

    PubMed Central

    Brown, Richard J. C.; Keates, Adam C.; Brewer, Paul J.

    2010-01-01

    An assessment of the sensitivities of the critical parameters in the ASTM D6423 documentary standard method for the measurement of pHe in (bio)ethanol has been undertaken. Repeatability of measurements made using the same glass electrode and reproducibility between different glass electrodes have been identified as the main contributors to the uncertainty of the values produced. Strategies to reduce the uncertainty of the measurement have been identified and tested. Both increasing the time after which the pHe measurement is made following immersion in the sample, and rinsing the glass electrode with ethanol prior to immersion in the sample, have been shown to be effective in reducing the uncertainty of the numerical value produced. However, it is acknowledged that the values produced using these modified approaches may not be directly compared with those obtained using the documentary ASTM method since pHe is defined operationally by the process used to measure it. PMID:22163451

  15. Repeated-batch operation of surface-aerated fermentor for bioethanol production from the hydrolysate of seaweed Sargassum sagamianum.

    PubMed

    Yeon, Ji-Hyeon; Lee, Sang-Eun; Choi, Woon Yong; Kang, Do Hyung; Lee, Hyoen-Yong; Jung, Kyung-Hwan

    2011-03-01

    In this study, we investigated the feasibility of sustainable long-term bioethanol production from the hydrolysate of a brown seaweed, Sargassum sagamianum. Because the hydrolysate was prepared as a liquid solution using a hightemperature liquefying system, a repeated-batch operation was utilized as the operational strategy for bioethanol production. Additionally, we used surface aeration to improve bioethanol production from the hydrolysate containing C5 monosaccharides such as xylose. In this study, the C5 monosaccharide-utilizable yeast strain Pichia stipitis was used for bioethanol production. Therefore, based on this repeated-batch flask culture, we designed a surface-aerated repeated-batch fermentor culture, in which the aeration was finely controlled at 100 ml/min and delivered into the headspace of a 2.5-l fermentor. When the medium was replaced every 48 h, bioethanol was continuously produced for 200 h under repeated-batch fermentor culture, where the level of bioethanol production was about 9~10 (g/l). Additionally, the bioethanol yield based on the reducing sugar was about 0.386, which was the average value throughout four consecutive cultures and was about 74.5% of the theoretical value. In addition, the bioethanol yield based on quantitative TLC analyses of glucose and xylose was about 0.431, which was the average value throughout four consecutive cultures and was about 84.3% of theoretical value. Consequently, throughout this repeated-batch operation, we demonstrated that it was actually feasible to produce bioethanol from the hydrolysate of seaweed S. sagamianum. In addition, the approach described here is a practical strategy for commercial bioethanol production from seaweed, particularly for finely controlling aeration through surface aeration.

  16. Influence of multi-look processing to SAR ship detection

    NASA Astrophysics Data System (ADS)

    Yang, Jingsong; Wang, Juan; Xiao, Qingmei; Chen, Peng; Huang, Weigen

    2009-10-01

    Single look complex data collected by SIR-C SAR are used to generate images of different looks by multi-look processing. The equivalent number of looks (ENL), spatial resolution, and ship-sea contrast of these images are analyzed. It shows that on the one hand, multi-look processing increases ENL hence improves image quality which is good for ship detection; on the other hand, multi-look processing also decreases spatial resolution and ship-sea contrast which goes ill with ship detection. Two typical ship detection algorithms such as adaptive threshold algorithm (ATA) and K-distribution based algorithm (KBA) are used to detect ship targets from these multi-look processed images. Case studies show that the figures of merit (FOMs) for 3-look processed images using ATA algorithm and FOMs for 2-look processed images using KBA algorithm are relatively larger. This means the most appropriate choice of multi-look processing of SAR images for ship detection is 2 or 3-look processing.

  17. Students' Preferences in Online Assessment Process: Influences on Academic Performances

    ERIC Educational Resources Information Center

    Cakiroglu, Unal; Erdogdu, Fatih; Kokoc, Mehmet; Atabay, Melek

    2017-01-01

    In the constructivist approach, various self-assessment techniques are being developed to enable students to assess themselves in the learning process. The purpose of the study is to investigate relation between students' preferences in assessment process and students' performances. The study was conducted with 67 sophomore students enrolled in…

  18. Factors in Cognitive Processing Which Influence Responses to Persuasive Communications.

    ERIC Educational Resources Information Center

    Mack, Herschel Lewis

    The author discusses a study designed to examine a communications problem from a cognitive processing viewpoint, to determine if a change in the amount of cognitive processing time available to a listener could affect his response to a given message. To specify the internal sources of input brought to a message receiving situation, the author used…

  19. Minimal Processing: Its Context and Influence in the Archival Community

    ERIC Educational Resources Information Center

    Gorzalski, Matt

    2008-01-01

    Since its publication in 2005, Mark A. Greene and Dennis Meissner's "More Product, Less Process: Revamping Traditional Archival Processing" has led to much discussion and self-examination within the archival community about working through backlogs. This article discusses the impact of Greene and Meissner's work and considers the questions and…

  20. Neural processes mediating contextual influences on human choice behaviour

    PubMed Central

    Rigoli, Francesco; Friston, Karl J.; Dolan, Raymond J.

    2016-01-01

    Contextual influences on choice are ubiquitous in ecological settings. Current evidence suggests that subjective values are normalized with respect to the distribution of potentially available rewards. However, how this context-sensitivity is realised in the brain remains unknown. To address this, here we examine functional magnetic resonance imaging (fMRI) data during performance of a gambling task where blocks comprise values drawn from one of two different, but partially overlapping, reward distributions or contexts. At the beginning of each block (when information about context is provided), hippocampus is activated and this response is enhanced when contextual influence on choice increases. In addition, response to value in ventral tegmental area/substantia nigra (VTA/SN) shows context-sensitivity, an effect enhanced with an increased contextual influence on choice. Finally, greater response in hippocampus at block start is associated with enhanced context sensitivity in VTA/SN. These findings suggest that context-sensitive choice is driven by a brain circuit involving hippocampus and dopaminergic midbrain. PMID:27535770

  1. Integrated bioethanol and protein production from brown seaweed Laminaria digitata.

    PubMed

    Hou, Xiaoru; Hansen, Jonas Høeg; Bjerre, Anne-Belinda

    2015-12-01

    A wild-growing glucose-rich (i.e. 56.7% glucose content) brown seaweed species Laminaria digitata, collected from the North Coast of Denmark in August 2012, was used as the feedstock for an integrated bioethanol and protein production. Glutamic acid and aspartic acid are the two most abundant amino acids in the algal protein, both with proportional content of 10% in crude protein. Only minor pretreatment of milling was used on the biomass to facilitate the subsequent enzymatic hydrolysis and fermentation. The Separate Hydrolysis and Fermentation (SHF) resulted in obviously higher ethanol yield than the Simultaneous Saccharification and Fermentation (SSF). High conversion rate at maximum of 84.1% glucose recovery by enzymatic hydrolysis and overall ethanol yield at maximum of 77.7% theoretical were achieved. Protein content in the solid residues after fermentation was enriched by 2.7 fold, with similar distributions of amino acids, due to the hydrolysis of polymers in the seaweed cell wall matrix.

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

    PubMed

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

    2010-09-01

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

  3. Prospects for increasing starch and sucrose yields for bioethanol production.

    PubMed

    Smith, Alison M

    2008-05-01

    In the short term, the production of bioethanol as a liquid transport fuel is almost entirely dependent on starch and sugars from existing food crops. The sustainability of this industry would be enhanced by increases in the yield of starch/sugar per hectare without further inputs into the crops concerned. Efforts to achieve increased yields of starch over the last three decades, in particular via manipulation of the enzyme ADPglucose pyrophosphorylase, have met with limited success. Other approaches have included manipulation of carbon partitioning within storage organs in favour of starch synthesis, and attempts to manipulate source-sink relationships. Some of the most promising results so far have come from manipulations that increase the availability of ATP for starch synthesis. Future options for achieving increased starch contents could include manipulation of starch degradation in organs in which starch turnover is occurring, and introduction of starch synthesis into the cytosol. Sucrose accumulation is much less well understood than starch synthesis, but recent results from research on sugar cane suggest that total sugar content can be greatly increased by conversion of sucrose into a non-metabolizable isomer. A better understanding of carbohydrate storage and turnover in relation to carbon assimilation and plant growth is required, both for improvement of starch and sugar crops and for attempts to increase biomass production in second-generation biofuel crops.

  4. Bioethanol from lignocelluloses: Status and perspectives in Brazil.

    PubMed

    Soccol, Carlos Ricardo; Vandenberghe, Luciana Porto de Souza; Medeiros, Adriane Bianchi Pedroni; Karp, Susan Grace; Buckeridge, Marcos; Ramos, Luiz Pereira; Pitarelo, Ana Paula; Ferreira-Leitão, Viridiana; Gottschalk, Leda Maria Fortes; Ferrara, Maria Antonieta; da Silva Bon, Elba Pinto; de Moraes, Lidia Maria Pepe; Araújo, Juliana de Amorim; Torres, Fernando Araripe Gonçalves

    2010-07-01

    The National Alcohol Program--PróAlcool, created by the government of Brazil in 1975 resulted less dependency on fossil fuels. The addition of 25% ethanol to gasoline reduced the import of 550 million barrels oil and also reduced the emission CO(2) by 110 million tons. Today, 44% of the Brazilian energy matrix is renewable and 13.5% is derived from sugarcane. Brazil has a land area of 851 million hectares, of which 54% are preserved, including the Amazon forest (350 million hectares). From the land available for agriculture (340 million hectares), only 0.9% is occupied by sugarcane as energy crop, showing a great expansion potential. Studies have shown that in the coming years, ethanol yield per hectare of sugarcane, which presently is 6000 L/ha, could reach 10,000 L/ha, if 50% of the produced bagasse would be converted to ethanol. This article describes the efforts of different Brazilian institutions and research groups on second generation bioethanol production, especially from sugarcane bagasse.

  5. Production of bioethanol using agricultural waste: Banana pseudo stem

    PubMed Central

    Ingale, Snehal; Joshi, Sanket J.; Gupte, Akshaya

    2014-01-01

    India is amongst the largest banana (Musa acuminata) producing countries and thus banana pseudo stem is commonly available agricultural waste to be used as lignocellulosic substrate. Present study focuses on exploitation of banana pseudo stem as a source for bioethanol production from the sugars released due to different chemical and biological pretreatments. Two fungal strains Aspergillus ellipticus and Aspergillus fumigatus reported to be producing cellulolytic enzymes on sugarcane bagasse were used under co-culture fermentation on banana pseudo stem to degrade holocellulose and facilitate maximum release of reducing sugars. The hydrolysate obtained after alkali and microbial treatments was fermented by Saccharomyces cerevisiae NCIM 3570 to produce ethanol. Fermentation of cellulosic hydrolysate (4.1 g%) gave maximum ethanol (17.1 g/L) with yield (84%) and productivity (0.024 g%/h) after 72 h. Some critical aspects of fungal pretreatment for saccharification of cellulosic substrate using A. ellipticus and A. fumigatus for ethanol production by S. cerevisiae NCIM 3570 have been explored in this study. It was observed that pretreated banana pseudo stem can be economically utilized as a cheaper substrate for ethanol production. PMID:25477922

  6. A Multiple Antibiotic-Resistant Enterobacter cloacae Strain Isolated from a Bioethanol Fermentation Facility

    PubMed Central

    Murphree, Colin A.; Li, Qing; Heist, E. Patrick; Moe, Luke A.

    2014-01-01

    An Enterobacter cloacae strain (E. cloacae F3S3) that was collected as part of a project to assess antibiotic resistance among bacteria isolated from bioethanol fermentation facilities demonstrated high levels of resistance to antibiotics added prophylactically to bioethanol fermentors. PCR assays revealed the presence of canonical genes encoding resistance to penicillin (ampC) and erythromycin (ermG). Assays measuring biofilm formation under antibiotic stress indicated that erythromycin induced biofilm formation in E. cloacae F3S3. Planktonic growth and biofilm formation were observed at a high ethanol content, indicating E. cloacae F3S3 can persist in a bioethanol fermentor under the highly variable environmental conditions found in fermentors. PMID:24941895

  7. Feasibility of bioethanol production from tubers of Dioscorea sansibarensis and Pyrenacantha kaurabassana.

    PubMed

    Moshi, Anselm P; Nyandele, Jane P; Ndossi, Humphrey P; Eva, Sosovele M; Hosea, Ken M

    2015-11-01

    Inedible tubers from Dioscorea sansibarensis (DS) and Pyrenacantha kaurabassana (PK) were found to be suitable feedstock for bioethanol production. Important composition parameters for bioethanol production for DS and PK are dry matter (% fresh tubers) ca. 20 and 6, total carbohydrates % dry weight base (db) ca. 68 and 47 and total protein (% db) ca. 16 and 10, respectively. DS and PK were found to contain inulin and galactomannan as principal polysaccharides (% of total carbohydrate) ca. 90 and 70, respectively. Diluted acid hydrolysis yielded ca. 100% of total reducing sugars. Ethanol yield ca. 56 and 35g/L was obtained at high efficiency through batch fermentation of acid hydrolysate (25% w/v) of DS and PK, respectively. A simple technique of recording and monitoring ethanol through CO2 generated during fermentation correlated strongly with HPLC measurement R(2)=0.99. Thus, tubers from these plants are potential feedstocks for bioethanol production with no competing uses.

  8. Comparison of hydrophilic variation and bioethanol production of furfural residues after delignification pretreatment.

    PubMed

    Bu, Lingxi; Tang, Yong; Xing, Yang; Zhang, Weiming; Shang, Xinhui; Jiang, Jianxin

    2014-01-01

    Furfural residue (FR) is a waste lignocellulosic material with enormous potential for bioethanol production. In this study, bioethanol production from FR after delignification was compared. Hydrophilic variation was measured by conductometric titration to detect the relationship between hydrophilicity and bioethanol production. It was found that ethanol yield increased as delignification enhanced, and it reached up to 75.6% of theoretical yield for samples with 8.7% lignin. The amount of by-products decreased as delignification increased. New inflection points appeared in conductometric titration curves of samples that were partially delignified, but they vanished in the curves of the highly delignified samples. Total charges and carboxyl levels increased after slight delignification, and they decreased upon further delignification. These phenomena suggested some new hydrophilic groups were formed during pretreated delignification, which would be beneficial to enzymatic hydrolysis. However, some newly formed groups may act as toxicant to the yeast during simultaneous saccharification and fermentation.

  9. Display of phytase on the cell surface of Saccharomyces cerevisiae to degrade phytate phosphorus and improve bioethanol production.

    PubMed

    Chen, Xianzhong; Xiao, Yan; Shen, Wei; Govender, Algasan; Zhang, Liang; Fan, You; Wang, Zhengxiang

    2016-03-01

    Currently, development of biofuels as an alternative fuel has gained much attention due to resource and environmental challenges. Bioethanol is one of most important and dominant biofuels, and production using corn or cassava as raw materials has become a prominent technology. However, phytate contained in the raw material not only decreases the efficiency of ethanol production, but also leads to an increase in the discharge of phosphorus, thus impacting on the environment. In this study, to decrease phytate and its phosphorus content in an ethanol fermentation process, Saccharomyces cerevisiae was engineered through a surface-displaying system utilizing the C-terminal half of the yeast α-agglutinin protein. The recombinant yeast strain, PHY, was constructed by successfully displaying phytase on the surface of cells, and enzyme activity reached 6.4 U/g wet biomass weight. Ethanol productions using various strains were compared, and the results demonstrated that the specific growth rate and average fermentation rate of the PHY strain were higher 20 and 18 %, respectively, compared to the control strain S. cerevisiae CICIMY0086, in a 5-L bioreactor process by simultaneous saccharification and fermentation. More importantly, the phytate phosphorus concentration decreased by 89.8 % and free phosphorus concentration increased by 142.9 % in dry vinasse compared to the control in a 5-L bioreactor. In summary, we constructed a recombinant S. cerevisiae strain displaying phytase on the cell surface, which could improve ethanol production performance and effectively reduce the discharge of phosphorus. The strain reported here represents a useful novel engineering platform for developing an environment-friendly system for bioethanol production from a corn substrate.

  10. Revision Vodcast Influence on Assessment Scores and Study Processes in Secondary Physics

    ERIC Educational Resources Information Center

    Marencik, Joseph J.

    2012-01-01

    A quasi-experimental switching replications design with matched participants was employed to determine the influence of revision vodcasts, or video podcasts, on students' assessment scores and study processes in secondary physics. This study satisfied a need for quantitative results in the area of vodcast influence on students' learning processes.…

  11. Revision Vodcast Influence on Assessment Scores and Study Processes in Secondary Physics

    ERIC Educational Resources Information Center

    Marencik, Joseph J.

    2012-01-01

    A quasi-experimental switching replications design with matched participants was employed to determine the influence of revision vodcasts, or video podcasts, on students' assessment scores and study processes in secondary physics. This study satisfied a need for quantitative results in the area of vodcast influence on students' learning processes.…

  12. Influence of Alloying Elements on the Laser Cutting Process

    NASA Astrophysics Data System (ADS)

    Ivarson, Anders; Powell, John; Siltanen, Jukka

    This paper presents an experimental investigation into how different alloying elements affect the laser-oxygen cutting process. Small variations in chemical composition of the material can lead to major changes in the overall laser-oxygen cutting process. The changes can appear as differences in cut edge roughness and/or adherent dross on the bottom of the cut. The primary causes of the process sensitivity have been identified as changes in surface tension and viscosity of the molten material in combination with changes in the exothermal reaction in the cut zone.

  13. Factors influencing kenaf harvesting and processing in the United States

    USDA-ARS?s Scientific Manuscript database

    The selection of the appropriate kenaf (Hibiscus cannabinus L., Malvaceae) production and harvest system is dependent on many factors, including location, equipment availability, storage options, processing plants, plant utilization, and economics. Since its first domestication, kenaf has consisten...

  14. Working Memory Influences Processing Speed and Reading Fluency in ADHD

    PubMed Central

    Jacobson, Lisa A.; Ryan, Matthew; Martin, Rebecca B.; Ewen, Joshua; Mostofsky, Stewart H.; Denckla, Martha B.; Mahone, E. Mark

    2012-01-01

    Processing speed deficits affect reading efficiency, even among individuals who recognize and decode words accurately. Children with ADHD who decode words accurately can still have inefficient reading fluency, leading to a bottleneck in other cognitive processes. This “slowing” in ADHD is associated with deficits in fundamental components of executive function underlying processing speed, including response selection. The purpose of the present study was to deconstruct processing speed in order to determine which components of executive control best explain the “processing” speed deficits related to reading fluency in ADHD. Participants (41 ADHD, 21 controls), ages 9-14, screened for language disorders, word reading deficits, and psychiatric disorders, were administered measures of copying speed, processing speed, reading fluency, working memory, reaction time, inhibition, and auditory attention span. Compared to controls, children with ADHD showed reduced oral and silent reading fluency, and reduced processing speed—driven primarily by deficits on WISC-IV Coding. In contrast, groups did not differ on copying speed. After controlling for copying speed, sex, severity of ADHD-related symptomatology, and GAI, slowed “processing” speed (i.e., Coding) was significantly associated with verbal span and measures of working memory, but not with measures of response control/inhibition, lexical retrieval speed, reaction time, or intra-subject variability. Further, “processing” speed (i.e., Coding, residualized for copying speed) and working memory were significant predictors of oral reading fluency. Abnormalities in working memory and response selection (which are frontally-mediated and enter into the output side of processing speed) may play an important role in deficits in reading fluency in ADHD, potentially more than posteriorally-mediated problems with orienting of attention or perceiving the stimulus. PMID:21287422

  15. Contextual Influences on Eating Behaviors: Heuristic Processing and Dietary Choices

    PubMed Central

    Cohen, Deborah A.; Babey, Susan H.

    2013-01-01

    This paper reviews some of the evidence that dietary behaviors are, in large part, the consequence of automatic responses to contextual food cues, many of which lead to increased caloric consumption and poor dietary choices. We describe studies that illustrate how these automatic mechanisms underlie eating behaviors, as well as evidence that individuals are subject to inherent cognitive limitations, and mostly lack the capacity to consistently recognize, ignore or resist contextual cues that encourage eating. Restaurants and grocery stores are the primary settings from which people obtain food. These settings are often designed to maximize sales of food by strategically placing and promoting items to encourage impulse purchases. Although a great deal of marketing research is proprietary, this paper describes some of the published studies that indicate that changes in superficial characteristics of food products, including packaging and portion sizes, design, salience, health claims, and labeling strongly influence food choices and consumption in ways for which people generally lack insight. We discuss whether contextual influences might be considered environmental risk factors from which individuals may need the kinds of protections that fall under the mission of public health. PMID:22551473

  16. Language influences number processing--a quadrilingual study.

    PubMed

    Moeller, Korbinian; Shaki, Samuel; Göbel, Silke M; Nuerk, Hans-Christoph

    2015-03-01

    Reading/writing direction or number word formation influence performance even in basic numerical tasks such as magnitude comparison. However, so far the interaction of these language properties has not been evaluated systematically. In this study we tested English, German, Hebrew, and Arab participants realizing a natural 2 × 2 design of reading/writing direction (left-to-right vs. right-to-left) and number word formation (non-inverted vs. inverted, i.e., forty-seven vs. seven-and-forty). Symbolic number magnitude comparison was specifically influenced by the interaction of reading/writing direction and number word formation: participants from cultures where reading direction and the order of tens and units in number words are incongruent (i.e., German and Hebrew) exhibited more pronounced unit interference in place-value integration. A within-group comparison indicated that this effect was not due to differences in education. Thus, basic cultural differences in numerical cognition were driven by natural language variables and their specific combination.

  17. Influence of radiation processing of grapes on wine quality

    NASA Astrophysics Data System (ADS)

    Gupta, Sumit; Padole, Rupali; Variyar, Prasad S.; Sharma, Arun

    2015-06-01

    Grapes (Var. Shiraz and Cabernet) were subjected to radiation processing (up to 2 kGy) and wines were prepared and matured (4 months, 15 °C). The wines were analyzed for chromatic characteristics, total anthocyanin (TA), phenolic (TP) and total antioxidant (TAC) content. Aroma of wines was analyzed by GC/MS and sensory analysis was carried out using descriptive analysis. TA, TP and TAC were 77, 31 and 37 percent higher for irradiated (1500 Gy) Cabernet wines, while irradiated Shiraz wines demonstrated 47, 18 and 19 percent higher TA, TP and TAC, respectively. HPLC-DAD analysis revealed that radiation processing of grapes resulted in increased extraction of phenolic constituents in wine with no qualitative changes. No major radiation induced changes were observed in aroma constituents of wine. Sensory analysis revealed that 1500 Gy irradiated samples had higher fruity and berry notes. Thus, radiation processing of grapes resulted in wines with improved organoleptic and antioxidant properties.

  18. Influence of processing on functionality of milk and dairy proteins.

    PubMed

    Augustin, Mary Ann; Udabage, Punsandani

    2007-01-01

    The inherent physical functionality of dairy ingredients makes them useful in a range of food applications. These functionalities include their solubility, water binding, viscosity, gelation, heat stability, renneting, foaming, and emulsifying properties. The suitability of dairy ingredients for an application can be further tailored by altering the structure of the proteins using appropriate processes. The processes discussed include physical modification (heat treatment, acidification, addition of mineral slats, homogenization, and shear), enzymatic modification (renneting, hydrolysis, and transglutamination), and chemical modification (use of chemical agents and the Maillard reaction). Emerging food processes (high pressure and ultrasound) are also discussed. The challenges for using dairy ingredients for the delivery of nutrients and bioactive components, while maintaining physical functionality, are also highlighted. There is a need for continued research into the fundamental aspects of milk proteins and their responses to various stresses for further differentiation of milk products and for the delivery of ingredients with consistent quality for target applications.

  19. Influence of cultivar and processing on cherry (Prunus avium) allergenicity.

    PubMed

    Primavesi, L; Brenna, O V; Pompei, C; Pravettoni, V; Farioli, L; Pastorello, E A

    2006-12-27

    Oral allergy syndrome is an immediate food allergic event that affects lips, mouth, and pharynx, is often triggered by fruits and vegetables, and may be associated with pollinosis. Here, we report on the allergenic pattern of different varieties of cherry (Prunus avium) and results obtained by applying several technological processes to the selected varieties. Whole cherries were submitted to chemical peeling, thermal treatment, and syruping processes, and the relative protein extracts were analyzed by in vitro (sodium dodecyl sulfate-polyacrylamide gel electrophoresis and immunoblotting analysis) and in vivo tests (skin prick test). Electrophoretic analyses demonstrated that there was no marked difference among cherry cultivars. Chemical peeling successfully removed Pru av 3, a lipid transfer protein (LTP) responsible for oral allergy syndrome in patients without pollinosis, leading to the industrial production of cherry hypoallergenic derivatives. Furthermore, the syruping process removed almost all allergenic proteins to whom patients with pollinosis are responsive. In vivo tests confirmed electrophoretic results.

  20. Reauthorization Ready: How NASFAA Influences the Higher Education Policymaking Process

    ERIC Educational Resources Information Center

    McClean Coval, Megan

    2015-01-01

    The Higher Education Act (HEA) is due to be reauthorized by Congress and the higher education policy community is working hard to be a part of those efforts. The National Association of Student Financial Aid Administrators (NASFAA) plays a unique role in this process, as the HEA contains the legislation behind all of the federal student financial…

  1. Hand Dominance Influences the Processing of Observed Bodies

    ERIC Educational Resources Information Center

    Gardner, Mark R.; Potts, Rosalind

    2010-01-01

    In motor tasks, subgroups of lefthanders have been shown to differ in the distribution of attention about their own bodies. The present experiment examined whether similar attentional biases also apply when processing observed bodies. Sixteen right handers (RHs), 22 consistent left handers (CLHs) and 11 relatively ambidextrous inconsistent left…

  2. Regional softwood sawmill processing variables as influenced by productive capacity

    Treesearch

    P. H. Steele; F. G. Wagner; K. E. Skog

    The relationship between annual softwood sawmill production and lumber processing variables was examined using data from Sawmill Improvement Program (SIP) studies of 650 softwood mills. The variables were lumber recovery factor (LRF); headrig and resaw kerf width; total sawing variation, rough green size, and oversizing-undersizing for 4/4 and 8/4 lumber; planer...

  3. Influence of Distal and Proximal Cognitive Processes on Word Reading

    ERIC Educational Resources Information Center

    Das, J. P.; Georgiou, George; Janzen, Troy

    2008-01-01

    The objectives of the present study were twofold: (a) to explore the interrelationship among distal, proximal cognitive skills, and word reading; and (b) to identify those cognitive processes that predict phonological awareness and rapid naming. Seventy First-Nation Canadian children attending grades 3 and 4 were examined on phonological…

  4. The Influence of Context on Hemispheric Recruitment during Metaphor Processing

    ERIC Educational Resources Information Center

    Diaz, Michele T.; Hogstrom, Larson J.

    2011-01-01

    Although the left hemisphere's prominence in language is well established, less emphasis has been placed on possible roles for the right hemisphere. Behavioral, patient, and neuroimaging research suggests that the right hemisphere may be involved in processing figurative language. Additionally, research has demonstrated that context can modify…

  5. Direct Influence of English Teachers in the Teaching Learning Process

    ERIC Educational Resources Information Center

    Inamullah, Hafiz Muhammad; Hussain, Ishtiaq; Ud Din, M. Naseer

    2008-01-01

    Teachers play a vital role in the classroom environment. Interaction between teacher and students is an essential part of the teaching/learning process. An educator, Flanders originally developed an instrument called Flanders Interaction Analysis (FIA). The FIA system was designed to categorize the types, quantity of verbal interaction and direct…

  6. When Family Considerations Influence Work Decisions: Decision-Making Processes

    ERIC Educational Resources Information Center

    Powell, Gary N.; Greenhaus, Jeffrey H.

    2012-01-01

    The work-family literature has provided an abundance of evidence that various family factors are linked to various work decisions, suggesting that the "family-relatedness" of work decisions is a prevalent phenomenon (Greenhaus & Powell, 2012). However, the cognitive processes by which such linkages occur have received little attention. We offer a…

  7. Hand Dominance Influences the Processing of Observed Bodies

    ERIC Educational Resources Information Center

    Gardner, Mark R.; Potts, Rosalind

    2010-01-01

    In motor tasks, subgroups of lefthanders have been shown to differ in the distribution of attention about their own bodies. The present experiment examined whether similar attentional biases also apply when processing observed bodies. Sixteen right handers (RHs), 22 consistent left handers (CLHs) and 11 relatively ambidextrous inconsistent left…

  8. Reauthorization Ready: How NASFAA Influences the Higher Education Policymaking Process

    ERIC Educational Resources Information Center

    McClean Coval, Megan

    2015-01-01

    The Higher Education Act (HEA) is due to be reauthorized by Congress and the higher education policy community is working hard to be a part of those efforts. The National Association of Student Financial Aid Administrators (NASFAA) plays a unique role in this process, as the HEA contains the legislation behind all of the federal student financial…

  9. Influences of Information Availability on Cognitive Processes in Person Perception.

    ERIC Educational Resources Information Center

    Lingle, John H.; Ostrom, Thomas M.

    Three experiments were conducted investigating information processing in a person perception task. A sequential judgement paradigm was employed in which subjects judged the suitability of stimulus persons for two different occupations. Traits describing each person were present for subjects' first judgements but not their second. Second decision…

  10. The Influence of Affect on Social-Information Processing.

    ERIC Educational Resources Information Center

    Bryan, Tanis; Sullivan-Burstein, Karen; Mathur, Sarup

    1998-01-01

    A study examined the impact of four affect-induction conditions (self-induced positive affect, music-induced positive affect, music-induced negative affect, and neutral affect) on the social-information-processing skills of 96 seventh-grade students with and without learning disabilities. Students in the self-induced positive condition generated…

  11. External Influences on an Internal Process: Supporting Preservice Teacher Research

    ERIC Educational Resources Information Center

    Schulte, Ann; Klipfel, Lyndsay Halpin

    2016-01-01

    In an effort to better understand how participating in teacher research as a student teacher compares to conducting it as a practicing teacher, a teacher educator and her former teacher education student engaged in a collaborative dialogue. They focus their reflections in this article on the impact of external forces on the process of teacher…

  12. Personality and Information Processing Speed: Independent Influences on Intelligent Performance

    ERIC Educational Resources Information Center

    Bates, Timothy C.; Rock, Andrew

    2004-01-01

    Raven's matrices and inspection time (IT) were recorded from 56 subjects under five arousal levels. Raven's and IT correlated strongly (r = -0.7) as predicted by processing-speed theories of "g." In line with Eysenck's [Eysenck, H. J. (1967). "The biological basis of personality". Springfield, IL: Thomas] arousal theory of extraversion, there was…

  13. Replisome mechanics: lagging strand events that influence speed and processivity

    PubMed Central

    Georgescu, Roxana E.; Yao, Nina; Indiani, Chiara; Yurieva, Olga; O'Donnell, Mike E.

    2014-01-01

    The antiparallel structure of DNA requires lagging strand synthesis to proceed in the opposite direction of the replication fork. This imposes unique events that occur only on the lagging strand, such as primase binding to DnaB helicase, RNA synthesis, and SS B antigen (SSB) displacement during Okazaki fragment extension. Single-molecule and ensemble techniques are combined to examine the effect of lagging strand events on the Escherichia coli replisome rate and processivity. We find that primase activity lowers replisome processivity but only when lagging strand extension is inoperative. rNTPs also lower replisome processivity. However, the negative effects of primase and rNTPs on processivity are overcome by the extra grip on DNA provided by the lagging strand polymerases. Visualization of single molecules reveals that SSB accumulates at forks and may wrap extensive amounts of single-strand DNA. Interestingly SSB has an inter-strand positive effect on the rate of the leading strand based in its interaction with the replicase χ-subunit. Further, the lagging strand polymerase is faster than leading strand synthesis, indicating that replisome rate is limited by the helicase. Overall, lagging strand events that impart negative effects on the replisome are counterbalanced by the positive effects of SSB and additional sliding clamps during Okazaki fragment extension. PMID:24829446

  14. External Influences on an Internal Process: Supporting Preservice Teacher Research

    ERIC Educational Resources Information Center

    Schulte, Ann; Klipfel, Lyndsay Halpin

    2016-01-01

    In an effort to better understand how participating in teacher research as a student teacher compares to conducting it as a practicing teacher, a teacher educator and her former teacher education student engaged in a collaborative dialogue. They focus their reflections in this article on the impact of external forces on the process of teacher…

  15. The Influence of Context on Hemispheric Recruitment during Metaphor Processing

    ERIC Educational Resources Information Center

    Diaz, Michele T.; Hogstrom, Larson J.

    2011-01-01

    Although the left hemisphere's prominence in language is well established, less emphasis has been placed on possible roles for the right hemisphere. Behavioral, patient, and neuroimaging research suggests that the right hemisphere may be involved in processing figurative language. Additionally, research has demonstrated that context can modify…

  16. Personality and Information Processing Speed: Independent Influences on Intelligent Performance

    ERIC Educational Resources Information Center

    Bates, Timothy C.; Rock, Andrew

    2004-01-01

    Raven's matrices and inspection time (IT) were recorded from 56 subjects under five arousal levels. Raven's and IT correlated strongly (r = -0.7) as predicted by processing-speed theories of "g." In line with Eysenck's [Eysenck, H. J. (1967). "The biological basis of personality". Springfield, IL: Thomas] arousal theory of extraversion, there was…

  17. Processes influencing rainfall features in the Amazonian region

    NASA Astrophysics Data System (ADS)

    Gerken, T.; Chamecki, M.; Fuentes, J. D.; Katul, G. G.; Fitzjarrald, D. R.; Manzi, A. O.; Nascimento dos Santos, R. M.; von Randow, C.; Stoy, P. C.; Tota, J.; Trowbridge, A.; Schumacher, C.; Machado, L.

    2014-12-01

    The Amazon is globally unique as it experiences the deepest atmospheric convection with important teleconnections to other parts of the Earth's climate system. In the Amazon Basin a large fraction of the local evapotranspiration is recycled through the formation of deep convective precipitating storms. Deep convection occurs due to moist thermodynamic conditions associated with elevated amounts of convective available potential energy. Aerosols invigorate the formation of convective storms in the Amazon via their unique concentrations, physical size, and chemical composition to activate into cloud condensation nuclei (CCN), but important aspects of aerosol/precipitation feedbacks remain unresolved. During the wet season, low atmospheric aerosol concentrations prevail in the pristine tropical air masses. These conditions have led to the Green Ocean hypothesis, which compares the clean tropical air to maritime air-masses and emphasizes biosphere-atmosphere feedbacks, to explain the features of the convective-type rainfall events in the Amazon. Field studies have been designed to investigate these relationships and the development of mesoscale convective systems through the Green Ocean Amazon project and the GOAmazon Boundary Layer Experiment. From March to October 2014 a field experiment was conducted at the Cuieiras Biological Reserve (2°51' S, 54°58' W), 80 km north of the city of Manaus, Brazil. This investigation spans the biological, chemical, and physical conditions influencing emissions and reactions of precursors (biogenic and anthropogenic volatile organic compounds, VOCs), formation of aerosols and CCNs and transport out of the ABL, and their role in cloud formation and precipitation triggers. In this presentation we will show results on the magnitude turbulent fluxes of latent and sensible heat, CCN concentrations, and rain droplet size distribution for both the wet and dry season. Such influencing factors on precipitation, will be contrasted with the

  18. Acetic acid removal from corn stover hydrolysate using ethyl acetate and the impact on Saccharomyces cerevisiae bioethanol fermentation.

    PubMed

    Aghazadeh, Mahdieh; Ladisch, Michael R; Engelberth, Abigail S

    2016-07-08

    Acetic acid is introduced into cellulose conversion processes as a consequence of composition of lignocellulose feedstocks, causing significant inhibition of adapted, genetically modified and wild-type S. cerevisiae in bioethanol fermentation. While adaptation or modification of yeast may reduce inhibition, the most effective approach is to remove the acetic acid prior to fermentation. This work addresses liquid-liquid extraction of acetic acid from biomass hydrolysate through a pathway that mitigates acetic acid inhibition while avoiding the negative effects of the extractant, which itself may exhibit inhibition. Candidate solvents were selected using simulation results from Aspen Plus™, based on their ability to extract acetic acid which was confirmed by experimentation. All solvents showed varying degrees of toxicity toward yeast, but the relative volatility of ethyl acetate enabled its use as simple vacuum evaporation could reduce small concentrations of aqueous ethyl acetate to minimally inhibitory levels. The toxicity threshold of ethyl acetate, in the presence of acetic acid, was found to be 10 g L(-1) . The fermentation was enhanced by extracting 90% of the acetic acid using ethyl acetate, followed by vacuum evaporation to remove 88% removal of residual ethyl acetate along with 10% of the broth. NRRL Y-1546 yeast was used to demonstrate a 13% increase in concentration, 14% in ethanol specific production rate, and 11% ethanol yield. This study demonstrated that extraction of acetic acid with ethyl acetate followed by evaporative removal of ethyl acetate from the raffinate phase has potential to significantly enhance ethanol fermentation in a corn stover bioethanol facility. © 2016 American Institute of Chemical Engineers Biotechnol. Prog., 32:929-937, 2016.

  19. The role of rational and experiential processing in influencing the framing effect.

    PubMed

    Stark, Emily; Baldwin, Austin S; Hertel, Andrew W; Rothman, Alexander J

    2016-06-07

    Research on individual differences and the framing effect has focused primarily on how variability in rational processing influences choice. However, we propose that measuring only rational processing presents an incomplete picture of how participants are responding to framed options, as orthogonal individual differences in experiential processing might be relevant. In two studies, we utilize the Rational Experiential Inventory, which captures individual differences in rational and experiential processing, to investigate how both processing types influence decisions. Our results show that differences in experiential processing, but not rational processing, moderated the effect of frame on choice. We suggest that future research should more closely examine the influence of experiential processing on making decisions, to gain a broader understanding of the conditions that contribute to the framing effect.

  20. Influence of supercontinent cyclicity on global metallogenic processes: Main tendencies

    NASA Astrophysics Data System (ADS)

    Tkachev, A. V.; Rundquist, D. V.

    2016-08-01

    The distribution of large and superlarge mineral deposits (LSMD) of the most important raw materials is correlated with supercontinent cycles in the geological history of the Earth. The latter displays the distinct correlation between metallogenic activity and cyclic global endogenous processes reflected in quasi-regular cycles, which result eventually in the assembly and breakup of supercontinents. In the framework of these cycles, the maximums in the LSMD assembly coincide with periods of intense growth of the subcontinent crust owing to growth of the matter originated from juvenile sources (Kenoran, Columbian cycles) or with epochs of intense recycling of the mature crust (Pangean, Amasian cycles). The Rodinian cycle with minimum activity of these both endogenous processes demonstrates simultaneously minimum metallogenic activity. The distribution of most LSMD types generally follows these main tendencies.

  1. The influence of ambient medium density on laser ablation processes

    SciTech Connect

    Kilgo, III, Marvin Moses

    1995-11-01

    Interest in high flux transport processes has grown in recent years along with the ability and need to manipulate systems with microscopic length and time scales. These systems present unique engineering challenges. Because the time and length scales associated with these problems are very small, assumptions of local equilibrium, physical and mathematical smoothness of boundaries and the unambiguous definition of thermodynamic fields can not be automatically made, even though they may ultimately be acceptable. Furthermore, the observations are made on macroscopic or integrated scales. The large difference in scales between the temporal evolution of the process and the observation requires careful consideration of the claims made regarding the system`s microscopic, temporal behavior. In particular, consistency of a proposed model with observed results does not guarantee uniqueness, or predictive accuracy for the model. For these reasons, microscale heat transfer systems demand a careful consideration of the framework within which the experimentation and analysis are conducted.

  2. Do aqueous ternary complexes influence the TALSPEAK process?

    SciTech Connect

    Leggett, C. j.; Liu, G.; Jensen, M. P.; Chemical Sciences and Engineering Division

    2010-01-01

    The aqueous speciation of trivalent lanthanide and actinide cations in solutions containing DTPA (diethylenetriamine-N,N,N',N',N'-pentaacetic acid) and lactic acid were studied under conditions representative of the TALSPEAK process. Spectrophotometric titrations, fluorescence spectroscopy, and thermometric titrations were used to search for indications of ternary metal-DTPA-lactate complexes. The addition of lactate anions to metal-DTPA complexes was undetectable by any of these techniques, even at free lactate concentrations of 0.75 M. Although lactic acid is necessary for the optimal performance of the TALSPEAK process, we find that the fractions of aqueous ternary Ln3+/An3+-DTPA-lactate complexes are far too low to account for the observed acid dependence of TALSPEAK metal extraction.

  3. Influences on the triple alpha process beyond the Hoyle state

    NASA Astrophysics Data System (ADS)

    Diget, Christian Å; Borge, Maria J. G.; Boutami, Fafik; Dendooven, Peter; Eronen, Tommi; Fox, Simon P.; Fulton, Brian R.; Fynbo, Hans, O. U.; Jeppesen, Henrik B.; Jokinen, Ari; Jonson, Björn; Kankainen, Anu; Moore, Iain; Nieminen, Arto; Pedersen, Solveig G.; Penttila, Haikki; Pucknell, Victor F. E.; Rilsager, Karsten; Rinta-Antila, Sami; Tengblad, Olof; Wang, Youbao; Wilhelmsen, Katarina; Äystö, Juha

    The triple alpha process is studied using indirect methods. The beta decays of 12 N and 12 B are used to probe the triple alpha continuum of 12 C. Different independent breakup channels are identified, consistently showing that the 10 MeV strength is dominated by a 0 + state interfering with the Hoyle state ghost. The 13-14 MeV region on the other hand is dominated by a 2 + state.

  4. Post-secretion processing influences spider silk performance

    PubMed Central

    Blamires, Sean J.; Wu, Chung-Lin; Blackledge, Todd A.; Tso, I-Min

    2012-01-01

    Phenotypic variation facilitates adaptations to novel environments. Silk is an example of a highly variable biomaterial. The two-spidroin (MaSp) model suggests that spider major ampullate (MA) silk is composed of two proteins—MaSp1 predominately contains alanine and glycine and forms strength enhancing β-sheet crystals, while MaSp2 contains proline and forms elastic spirals. Nonetheless, mechanical properties can vary in spider silks without congruent amino acid compositional changes. We predicted that post-secretion processing causes variation in the mechanical performance of wild MA silk independent of protein composition or spinning speed across 10 species of spider. We used supercontraction to remove post-secretion effects and compared the mechanics of silk in this ‘ground state’ with wild native silks. Native silk mechanics varied less among species compared with ‘ground state’ silks. Variability in the mechanics of ‘ground state’ silks was associated with proline composition. However, variability in native silks did not. We attribute interspecific similarities in the mechanical properties of native silks, regardless of amino acid compositions, to glandular processes altering molecular alignment of the proteins prior to extrusion. Such post-secretion processing may enable MA silk to maintain functionality across environments, facilitating its function as a component of an insect-catching web. PMID:22628213

  5. Influence of estuarine processes on spatiotemporal variation in bioavailable selenium

    USGS Publications Warehouse

    Stewart, Robin; Luoma, Samuel N.; Elrick, Kent A.; Carter, James L.; van der Wegen, Mick

    2013-01-01

    Dynamic processes (physical, chemical and biological) challenge our ability to quantify and manage the ecological risk of chemical contaminants in estuarine environments. Selenium (Se) bioavailability (defined by bioaccumulation), stable isotopes and molar carbon-tonitrogen ratios in the benthic clam Potamocorbula amurensis, an important food source for predators, were determined monthly for 17 yr in northern San Francisco Bay. Se concentrations in the clams ranged from a low of 2 to a high of 22 μg g-1 over space and time. Little of that variability was stochastic, however. Statistical analyses and preliminary hydrodynamic modeling showed that a constant mid-estuarine input of Se, which was dispersed up- and down-estuary by tidal currents, explained the general spatial patterns in accumulated Se among stations. Regression of Se bioavailability against river inflows suggested that processes driven by inflows were the primary driver of seasonal variability. River inflow also appeared to explain interannual variability but within the range of Se enrichment established at each station by source inputs. Evaluation of risks from Se contamination in estuaries requires the consideration of spatial and temporal variability on multiple scales and of the processes that drive that variability.

  6. The influence of scopolamine on motor control and attentional processes

    PubMed Central

    Bestaven, Emma; Kambrun, Charline; Guehl, Dominique; Cazalets, Jean-René

    2016-01-01

    Background: Motion sickness may be caused by a sensory conflict between the visual and the vestibular systems. Scopolamine, known to be the most effective therapy to control the vegetative symptoms of motion sickness, acts on the vestibular nucleus and potentially the vestibulospinal pathway, which may affect balance and motor tasks requiring both attentional process and motor balance. The aim of this study was to explore the effect of scopolamine on motor control and attentional processes. Methods: Seven subjects were evaluated on four different tasks before and after a subcutaneous injection of scopolamine (0.2 mg): a one-minute balance test, a subjective visual vertical test, a pointing task and a galvanic vestibular stimulation with EMG recordings. Results: The results showed that the reaction time and the movement duration were not modified after the injection of scopolamine. However, there was an increase in the center of pressure displacement during the balance test, a decrease in EMG muscle response after galvanic vestibular stimulation and an alteration in the perception of verticality. Discussion: These results confirm that low doses of scopolamine such as those prescribed to avoid motion sickness have no effect on attentional processes, but that it is essential to consider the responsiveness of each subject. However, scopolamine did affect postural control and the perception of verticality. In conclusion, the use of scopolamine to prevent motion sickness must be considered carefully because it could increase imbalances in situations when individuals are already at risk of falling (e.g., sailing, parabolic flight). PMID:27169000

  7. Modeling evaporation from porous media influenced by atmospheric processes

    NASA Astrophysics Data System (ADS)

    Mosthaf, K.; Baber, K.; Flemisch, B.; Helmig, R.

    2012-04-01

    Modeling evaporation processes from partially saturated soils into the ambient air is a challenging task. It involves usually a variety of interacting processes and depends on the multitude of properties of the fluids and of the porous medium. Often, the ambient free-flow and the porous-medium compartments are modeled separately with a specification of the evaporation rate as boundary condition. We have developed a coupling concept, which allows the combined modeling of a free-flow and a porous-medium system under non-isothermal conditions with the evaporative fluxes across the soil-atmosphere interface as model output. It is based on flux continuity and local thermodynamic equilibrium at the interface. Darcy's law for multiple phases is used in the porous medium, whereas the ambient air flow is modeled as a compositional single-phase Stokes system. The concept has been implemented in the numerical simulator DuMux. A comparison of simulated and measured data from wind tunnel experiments performed in the group of D. Or (ETH Zürich) will be shown. Furthermore, the impact of several parameters, such as a varying wind velocity, temperature or different soil properties on the evaporation process has been analyzed in a numerical parameter study. The results will be presented and discussed.

  8. Influences on the Talent Development Process of Non-Classical Musicians: Psychological, Social and Environmental Influences

    ERIC Educational Resources Information Center

    Kamin, Sara; Richards, Hugh; Collins, Dave

    2007-01-01

    Twelve professional, non-classical musicians were interviewed about the impact of internal and external factors on their development as musicians. The data were qualitatively analyzed, and observations concerning psychological characteristics of developing excellence (PCDEs), social and environmental influences are reported. The insights of the…

  9. Influences on the Talent Development Process of Non-Classical Musicians: Psychological, Social and Environmental Influences

    ERIC Educational Resources Information Center

    Kamin, Sara; Richards, Hugh; Collins, Dave

    2007-01-01

    Twelve professional, non-classical musicians were interviewed about the impact of internal and external factors on their development as musicians. The data were qualitatively analyzed, and observations concerning psychological characteristics of developing excellence (PCDEs), social and environmental influences are reported. The insights of the…

  10. The influence of bodily experience on children's language processing.

    PubMed

    Wellsby, Michele; Pexman, Penny M

    2014-07-01

    The Body-Object Interaction (BOI) variable measures how easily a human body can physically interact with a word's referent (Siakaluk, Pexman, Aguilera, Owen, & Sears, ). A facilitory BOI effect has been observed with adults in language tasks, with faster and more accurate responses for high BOI words (e.g., mask) than for low BOI words (e.g., ship; Wellsby, Siakaluk, Owen, & Pexman, ). We examined the development of this effect in children. Fifty children (aged 6-9 years) and a group of 21 adults completed a word naming task with high and low BOI words. Younger children (aged 6-7 years) did not show a BOI effect, but older children (aged 8-9 years) showed a significant facilitory BOI effect, as did adults. Magnitude of children's BOI effect was related to age as well as reading skills. These results suggest that bodily experience (as measured by the BOI variable) begins to influence visual word recognition behavior by about 8 years of age. Copyright © 2014 Cognitive Science Society, Inc.

  11. Process design of press hardening with gradient material property influence

    SciTech Connect

    Neugebauer, R.; Schieck, F.; Rautenstrauch, A.

    2011-05-04

    Press hardening is currently used in the production of automotive structures that require very high strength and controlled deformation during crash tests. Press hardening can achieve significant reductions of sheet thickness at constant strength and is therefore a promising technology for the production of lightweight and energy-efficient automobiles. The manganese-boron steel 22MnB5 have been implemented in sheet press hardening owing to their excellent hot formability, high hardenability, and good temperability even at low cooling rates. However, press-hardened components have shown poor ductility and cracking at relatively small strains. A possible solution to this problem is a selective increase of steel sheet ductility by press hardening process design in areas where the component is required to deform plastically during crash tests. To this end, process designers require information about microstructure and mechanical properties as a function of the wide spectrum of cooling rates and sequences and austenitizing treatment conditions that can be encountered in production environments. In the present work, a Continuous Cooling Transformation (CCT) diagram with corresponding material properties of sheet steel 22MnB5 was determined for a wide spectrum of cooling rates. Heating and cooling programs were conducted in a quenching dilatometer. Motivated by the importance of residual elasticity in crash test performance, this property was measured using a micro-bending test and the results were integrated into the CCT diagrams to complement the hardness testing results. This information is essential for the process design of press hardening of sheet components with gradient material properties.

  12. Processes influencing seasonal hypoxia in the northern California Current System

    PubMed Central

    Connolly, T. P.; Hickey, B. M.; Geier, S. L.; Cochlan, W. P.

    2010-01-01

    This paper delineates the role of physical and biological processes contributing to hypoxia, dissolved oxygen (DO) < 1.4 mL/L, over the continental shelf of Washington State in the northern portion of the California Current System (CCS). In the historical record (1950–1986) during the summer upwelling season, hypoxia is more prevalent and severe off Washington than further south off northern Oregon. Recent data (2003–2005) show that hypoxia over the Washington shelf occurred at levels previously observed in the historical data. 2006 was an exception, with hypoxia covering ~5000 km2 of the Washington continental shelf and DO concentrations below 0.5 mL/L at the inner shelf, lower than any known previous observations at that location. In the four years studied, upwelling of low DO water and changes in source water contribute to interannual variability, but cannot account for seasonal decreases below hypoxic concentrations. Deficits of DO along salinity surfaces, indicating biochemical consumption of DO, vary significantly between surveys, accounting for additional decreases of 0.5–2.5 mL/L by late summer. DO consumption is associated with denitrification, an indicator of biochemical sediment processes. Mass balances of DO and nitrate show that biochemical processes in the water column and sediments each contribute ~50% to the total consumption of DO in near-bottom water. At shorter than seasonal time scales on the inner shelf, along-shelf advection of hypoxic patches and cross-shelf advection of seasonal gradients are both shown to be important, changing DO concentrations by 1.5 mL/L or more over five days. PMID:20463844

  13. Processes influencing seasonal hypoxia in the northern California Current System

    NASA Astrophysics Data System (ADS)

    Connolly, T. P.; Hickey, B. M.; Geier, S. L.; Cochlan, W. P.

    2010-03-01

    This paper delineates the role of physical and biological processes contributing to hypoxia, dissolved oxygen (DO) < 1.4 mL/L, over the continental shelf of Washington State in the northern portion of the California Current System. In the historical record (1950-1986), during the summer upwelling season, hypoxia is more prevalent and severe off Washington than further south off northern Oregon. Recent data (2003-2005) show that hypoxia over the Washington shelf occurred at levels previously observed in the historical data. The year 2006 was an exception, with hypoxia covering ˜5000 km2 of the Washington continental shelf and DO concentrations below 0.5 mL/L at the inner shelf, lower than any known previous observations at that location. In the 4 years studied, upwelling of low DO water and changes in source water contribute to interannual variability, but cannot account for seasonal decreases below hypoxic concentrations. Deficits of DO along salinity surfaces, indicating biochemical consumption of DO, vary significantly between surveys, accounting for additional decreases of 0.5-2.5 mL/L by late summer. DO consumption is associated with denitrification, an indicator of biochemical sediment processes. Mass balances of DO and nitrate show that biochemical processes in the water column and sediments each contribute ˜50% to the total consumption of DO in near-bottom water. At shorter than seasonal time scales on the inner shelf, along-shelf advection of hypoxic patches and cross-shelf advection of seasonal gradients are both shown to be important, changing DO concentrations by 1.5 mL/L or more over 5 days.

  14. Parameter Influence on Surfi-Sculpt Processing Efficiency

    NASA Astrophysics Data System (ADS)

    Earl, Caroline; Hilton, Paul; O'Neill, Bill

    The three-dimensional laser surface modification manufacturing technique, Surfi-Sculpt®, is thought to be driven by a melt pool instability that is dependent on a quasi steady-state temperature field. The melt pool instability can be controlled through a greater understanding of the heat input and selection of optimised laser processing parameters. This in turn enables the optimum production of a range of feature shapes, so that this new manufacturing technique can be applied in applications requiring increased surface area of the substrate or functional surface textures.

  15. Processing and nanostructure influences on mechanical properties of thermoelectric materials

    NASA Astrophysics Data Sys